Final Environmental Impact Report (EOEA File Number 8695)
and
Final Environmental Impact Statement
Volume 1 of 3
Boston Harbor, Massachusetts
Navigation Improvement Project and Berth Dredging Project
June 1995
US Army Corps
of Engineers
New England Division
Massachusetts
Port Authority
Maritime Department
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lll.ll., ,1,1
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FINAL
ENVIRONMENTAL IMPACT IfflPORT/ENVIRONMENTAL IMPACT STATEMENT
(FEIR/S)
Volume 1 of 3
BOSTON HARBOR NAVIGATION IMPROVEMENT DREDGING
AND
BERTH DREDGING PROJECT
RESPONSIBLE LEAD AGENCIES ARE:
U.S. Army Corps of Engineers Massachusetts Port Authority
Impact Analysis Division Maritime Department
424 Trapelo Road Boston Fish Pier II
Waltham, Massachusetts O2254 Boston, Massachusetts 02210
FEDERAL COOPERATING AGENCIES:
National Marine Fisheries Service, U.S. Fish and Wildlife Service,
and the U.S. Environmental Protection Agency
DOCUMENT WAS PREPARED BY:
Normandeau Associates Inc. U.S. Army Corps of Engineers
25 Nashua Road 424 Trapelo Road
Bedford, New Hampshire 03310-5500 Waltham, Massachusetts 02254
for the
Massachusetts Port Authority
This joint Federal and State document addresses the impacts
associated with the congressionally authorized navigation
improvement dredging and disposal of material from the Federal
navigation channel and associated berthing areas in Boston Harbor,
Massachusetts. The Reserved Channel and Mystic River would be
deepened from 35 feet mean low water (MLW) to 40 feet MLW. The
Chelsea Creek would be deepened from 35 feet MLW to 38 feet MLW.
Disposal of the underlying parent material is proposed at the
Massachusetts Bay Disposal Site. Disposal alternatives for the
silt material (maintenance material) ' overtopping the parent
material are assessed and the preferred alternative selected in
this FEIR/S.
Comments should be sent to Colonel Richardson at the U.S Army
Corps of Engineers and Ms. Trudy Coxe, Secretary, Executive Office
of Environmental Affairs, commonwealth of Massachusetts by the date
indicated in the transmittal letter. If you would like further
information on this document, Mr. Peter Jackson of the U.S. Army
Corps of Engineers can be reached at (617) 647-8861 or contact Ms.
Janeen Hansen, Massport, at (617) 973-5355.
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BOSTON HARBOR NAVIGATION IMPROVEMENT PROJECT
FINAL ENVIRONMENTAL IMPACT REPORT/STATEMENT
Volume 1
TABLE OF CONTENTS
Executive Summary [[[ ES-1
Chapter One: Introduction ............................. . ....................................... 1-1
1.1 PROJECT PURPOSE AND NEED [[[ 1-3
1.1.1 Historical Importance of the Port of Boston ................................................ 1-4
1.1.2 Economic Benefits of Project ..................... . ................................................ 1-5.
1.1,2.1 Navigational Efficiency. [[[ 1-5
1.1.2.2 Containerized Cargo Volumes. [[[ 1-5
1.1.2.3 Ability to Attract New Shipping Lines. .................................................. 1-6
1.1.2.4 Maintain Refined Oil Product Capacity ............................................... 1-6
1.2 PROCEDURAL HISTORY [[[ 1-7
1.2.1 Congressional Authorization ..................................... . ................................. 1-7
1.2.2 Public and Agency Review [[[ 1-9
1.2.3 Public Participation Process [[[ 1-10
1.2.4 Inter- Agency Coordination ........... . ....... . [[[ 1-10
1.3 SUMMARY OF MAJOR CHANGES FROM THE DEIR/S ______________________ 1-11
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TABLE OF CONTENTS (CONTINUED)
1.3.7 Detailed Dredge Management Plan 1-13
1.3.8 Summary of Changes 1-14
1.4 FORMAT OF THE FEffi/S l~15
Chapter Two: Project Description 2"1
2.1 PROJECT DESIGN ALTERNATIVES 2~l
2.1.1 No Action, No Maintenance Dredging 2-1
2.1.2 No Action, with Maintenance Dredging 2-3
2.1.3 Full Project - Three Channels, All Berths 2-4
2.1.3.1 Reserved Channel 2~*
2.1.3.2 Mystic River Channel. 2~5
2.1.3.3 Chelsea Creek Terminal : 2~6
2.1.3.4 Main Ship Channel • 2~6
2.1.3.5 Non-Structural Improvements at Presidents Roads. 2-6
2.1.3.6 Summary - 2~6
2.1.4 Expanded Project 2-7
2.1.5 Reduced Project 2'8
2.1.6 Delayed Action 2-8
2.2 COMPARISON OF PROJECT DESIGN ALTERNATIVES 2-9
2.3 FUTURE MAINTENANCE DREDGING 2-10
2.3.1 Quantity and Quality of Dredged Material 2-11
2.3.7.7 Quantity of Material 2~H
2.3.1.2 Quality of Material '. 2~12
2.3.2 Future Maintenance Dredging Cycle 2-12
2.3.3 Demonstration Projects 2-13
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TABLE OF CONTENTS (CONTINUED)
2.3.4 Disposal Options for Future Maintenance Dredged Material 2-14
2.3.4.1 Capping 2-14
2.3.4.2 Geotextile Containers 2-75
2.3.4.3 Treatment Technologies 2-16
Chapter Three: Disposal Site Alternatives 3-1
3.1 THE EVALUATION PROCESS .3-1
3.1.1 Identification of Disposal Concepts 3-3
3.1.1.1 Land-Based Alternatives 3-3
3.1.1.2 Aquatic Alternatives. 3-4
3.1.2 Identification of Potential Disposal Sites 3-6
3.1.2.1 Phase I Site Screening. 3-6
3.1.2.2 Phase IISite Screening 3-7
3.1.2.3 Phase HI Site Screening 3-77
3.7.2.4 Phase WSite Screening..; 3-77
3.2 SEDIMENT/SITE MATCHING 3-12
3.3 STJTTABIIJTY OF GENERIC TYPES OF DISPOSAL
ALTERNATIVES FOR DREDGED SILT 3-14
3.3.1 Land-Based Alternatives 3-14
3.3.2 Aquatic Alternatives 3-16
3.4 DEVELOPMENT OF DISPOSAL OPTIONS 3-20
3.4.1 Land-Based Options (A) 3-22
3.4.2 Aquatic Options (B) 3-23
in
/
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TABLE OF CONTENTS (CONTINUED)
3.4.3 Land-Based Aquatic Combinations (C) 3~25
3.4.4 Previously Used Aquatic Disposal Sites (D) 3'26
3.5 ALTERNATIVE TECHNOLOGY ASSESSMENT 3-27
3.5.1 Treatment Technologies 3~27
3.5.2 Technology Screening Criteria
3.5.3 Treatment Technology Rating
3.6 BENEFICIAL USES
3.6.1 Use of Rock Material - 3"33
3.6.2 Use of Parent Material 3"35
3.6.3 Summary of Beneficial Uses 3"36
3.7 PREFERRED DISPOSAL OPTION 3'37
3-30
3-31
3-33
Chapter Four: Selection of Preferred Disposal Location 4-1
4.1 LAND-BASED SITES 4"2
4.1.1 Generic Issues
4.1.1.1 Dewatering
4.1.1.2 Hauling.
4.1.1.3 Solid Waste Siting Suitability
4.1.2 Direct Impacts
4.1.2.1 Permanent Loss
4.1.2.2 Temporary Loss
4.1.2.3 Permanent Alterations
4.1.3 Indirect Impacts
.4-2
.4-3
.4-5
.4-5
,.4-6
.4-6
..4-7
.4-7
4.1.4 Identification of the Least Environmentally Damaging
Land-Based Alternatives 4~°
IV
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TABLE OF CONTENTS (CONTINUED)
4.2 AQUATIC SITES 4-8
4.2.1 Direct Impacts 4-10
4.2.1.1 Permanent Loss [404 (b)(l) Issues] 4-10
4.2.1.2 Temporary Loss 4-11
4.2.1.3 Permanent Alteration 4-11
4.2.1.4 Summary 4-15
4.2.2 Indirect Impacts 4-1
4.2.2.1 Water Quality Effects 4-16
4.2.2.2 Site Stability. 4-18
4.2.2.3 Downstream Impacts. 4-21
4.2.2.4 Biological Exposure Potential. 4-24
4.2.3 Identification of Least Environmentally
Damaging Aquatic Alternatives 4-28
4.4 PRACTICABILITY ANALYSIS 4-29
4.3.1 Availability , 4-30
4.3.1.1 Upland Sites 4-30
4.3.1.2 Aquatic Sites 4-30
4.3.2 Permittability 4-31
4.3.2.1 Upland Sites 4-31
4.3.2.2 Aquatic Sites 4-31
4.3.3 Constructability/Complexity of Engineering 4-32
4.3.3.1 Upland Sites 4-32
4.3.3.2 Aquatic Sites 4-33
4.3.4 Logistics 4-33
4.3.4.1 Upland Sites 4-33
4.3.4.2 Aquatic Sites 4-34
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TABLE OF CONTENTS (CONTINUED)
4.3.5 Monitoring 4-34
43.5.7 Upland Sites 4-34
4.3.5.2 Aquatic Sites 4-35
4.3.6 Conflicts with Other Activities 4-35
4.3.6.1 UplandSites 4-35
4.3.6.2 Aquatic Sites ...4-35
4.3.7 Capacity 4-36
4.3.8 Cost , 4-38
4.3.9 Future Use 4-38
4.3.9.1 UplandSites 4-39
4.3.9.2 Aquatic Sites 4-39
4.5 IDENTIFICATION OF THE PREFERRED ALTERNATIVE
FOR THE BOSTON HARBOR NAVIGATION IMPROVEMENT
AND BERTH DREDGING PROJECT (BHNIP) 4-40
4.6 FUTURE MAINTENANCE 4-41
Chapter Five: Dredging Management Plan 5-1
5.1 SELECTION OF DREDGING METHOD 5-1
5.1.1 Project Objectives 5-1
5.1.2 Physical Limitations 5-2
5.1.2 Turbidity 5-2
5.1.4 Trash and Debris Management 5-3
5.1.5 Compatibility with Disposal 5-3
5.1.6 Dredge Types 5-4
5.1.6.1 Mechanical Dredge 5-4
5.1.6.2 Hydraulic Dredge 5-5
5.1.6.3 Hopper Dredge 5-6
VI
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TABLE OF CONTENTS (CONTINUED)
5.1.7 Rock Excavation Equipment
5.1.8 Recommended Dredging Equipment and Performance Criteria 5-7
5.1.8.1 Recommended Equipment 5-7
5.1.8.2 Operational Controls 5-8
5.1.8.3 Contract and Specification Issues 5-9
5.2 DREDGING OPERATIONS 5-10
5.2.1 Project Mobilization 5-10
5.2.1.1 Upland Support Requirements 5-10
5.2.1.2 Navigation and Commercial Traffic 5-11
5.2.1.3 Structural Evaluation 5-11
5.2.1.4 Regulatory Constraints 5-11
5.2.1.5 Seasonal Limitations 5-12
5.2.2 Dredged Material Handling Procedures 5-12
5.2.2.1 Monitoring Requirements. 5-12
5.2.2.2 Environmental Bucket 5-12
5.2.2.3 Dredging Locations 5-13
5.2.2.4 Facility Construction 5-13
5.2.3 Dredging Sequencing 5-13
5.2.3.7 Site Prioritization 5-13
5.2.3.2 Material Prioritization 5-14
5.2.3.3 Schedule -.....: 5-14
5.2.3.4 Limitations 5-15
5.2.4 Blasting and Rock Removal 5-16
5.2.4.1 Locations 5-16
5.2.4.2 Seasonal Limitations 5-16
5.2.4.3 Mitigation 5-16
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TABLE OF CONTENTS (CONTINUED)
5.3 DREDGED MATERIAL DISPOSAL OPERATIONS 5-16
5.3.1 Equipment and Facilities 5~16
5.3.2 Impacts on Dredging Operations 5'17
5.3.3 Weather Restrictions - 5'17
5.3.4 Capping Operations • 5"17
5.4 CONSTRUCTION SEQUENCING 5-18
5.4.1 Dredging and Disposal Sequencing 5~18
5.4.2 Project Demobilization 5'20
5.5 SUMMARY OF CONSTRUCTION MITIGATION..... 5-20
5.5.1 Dredging 5~20
5.5.2 Rock Excavation • 5'21
5.5.3 Dredged Material Disposal - 5~21
5.6 MONITORING DURING DREDGING AND
DISPOSAL OPERATIONS 5-21
5.6.1 Dredge Performance 5-21
5.6.2 Environmental Impacts ^-23
5.6.3 Accountability and Supervision 5"23
5.7 LONG TERM MONITORING OF DISPOSAL SITES 5-24
5.7.1 DAMOS Monitoring Program and Parameters 5-24
5.7.2 Sampling Plan • 5'25
5.7.3 Reporting Requirements 5'26
5.8 CONTINGENCY PLANS 5-26
5.8.1 Project Delays • 5'26
5.8.2 Operations Issues 5~27
5.8.2.1 Operator Qualifications 5"27
5.8.2.2 Trash and Debris Management 5'27
5.8.2.3 Disposal Operations 5"28
\an
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TABLE OF CONTENTS (CONTINUED)
5.8.2.4 Permit Conditions Exceeded 5~28
5.8.2.5 Equipment Failure 5~29
5.8.3 Environmental Conditions 5'29
5.5.3.7 Weather Related Issues 5~29
5.8.3.2 Noise. • 5~30
5.8.3.3 Odor and Air Quality 5~30
Chapter Six: Summary of Project Impacts and
Mitigation Opportunities 6-1
6.1 PRIMARY IMPACTS OF PREFERRED PROJECT 6-1
6.1.1 Direct Impacts of Resource Areas 6-1
6.1.2 Dredging Impacts 6"3
6.1.2.1 Water Quality/Sediment Quality 6-3
6.1.2.2 Biological Resources ^
6.1.2.3 Threatened and Endangered Species 6-6
6.1.2.4 Historical and Archeological Resources 6-6
6.1.2.5 Noise and Odor. 6-6
6.1.2 Disposal Impacts 6'7
6.1.3.1 Water Quality/Sediment Quality 6-7
6.1.3.2 Biological Resources 6-7
6.1.2.3 Threatened and Endangered Species... 6-7
6.1.3.4 Historical and Archeological Resources 6-8
6.1.3.5 Noise and Odor 6-8
IX
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TABLE OF CONTENTS (CONTINUED)
6.2 SECONDARY IMPACTS 6'8
6.2.1 Vessel Traffic 6'8
6.2.2 Terminal Improvements - 6~8
6.2.3 Roadway Improvements 6-9
6.2.4 Growth of Fort Devens 6-9
6.3 CUMULATIVE IMPACTS 6'9
6.3.1 Maintenance Dredging 6-10
6.3.2 Relationship to Other Projects • 6-10
6.3.3 Irreversible and Irretrievable Commitment of Resources 6-11
6.4 MITIGATION FOR DREDGING AND DISPOSAL IMPACTS 6-11
6.4.1 Avoidance • 6-12
6.4.2 Minimization - 6-13
6.4.3 Rectification 6-13
6.4.4 Reduction or Elimination 6-13
6.4.5 Compensation 6-13
6.4.5.1 Summary ofPVF Conditions at the In-Channel Sites 6-14
6.4.5.2 Summary ofPVF Conditions at IMC 6-15
6.4.6 Resource Enhancement Concepts 6-16
6.4.7 Summary • 6-16
Chapter Seven: BHNIP Regulatory Status 7-1
7.1 LOCAL JURISDICTION 7-1
7.2 STATE JURISDICTION 7-!
7.2.1 Massachusetts Waterways Licensing Program
(M.G.L. c.91and310CMR9.00) 7-1
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TABLE OF CONTENTS (CONTINUED)
7.2.2 Massachusetts Wetland Protection Act
(M.G.L. c. 131, §40 and 310 CMR 10.00) 7-2
7.2.3 MCZM Jurisdictional Review and Policies Relative
to DPA's (M.G.L. c. 6a, § 2-7 and 301 CMR 20.00) 7-3
7.2.4 Massachusetts Division of Water Pollution Control
Clean Water Act 401 Certification (314 CMR 9.00) 7-4
7.3 FEDERAL JURISDICTION 7-5
Chapter Eight: Draft Section 61 Findings 8-1
8.1 DRAFT SECTION 61 FINDING FOR MASSPORT 8-1
8.1.1 Project Description 8-1
8.1.2 Summary of Project Impacts 8-4
8.1.3 Specific Impacts and Mitigation Measures 8-5
8.1.3.1 Impacts to Harbor Botton 8-5
8.1.3.2 Water Quality/Sediment Quality 8-5
8.1.3.3 Biological Resources 8-6
8.1.3.4 Operational Controls, Contingencies and Mitigation 8-6
8.1.3.5 Resource Enhancement Activities 8-7
8.1.4 Findings 8-7
8.2 MODEL SECTION 61 FINDING FOR DEP AGENCIES
8.2.1 Massachusetts Wetlands Protection Act
(MGL. c. 131, §40 and 310 CMR 10.00 8-8
8.2.2 Massachusetts Waterways Licensing Program
(MGL. c. 91 and 310 CMR 9.00) 8-10
i
8.2.3 MCZM Policies Applicable to the BHNIP..... 8-11
8.2.4 Section 401 Water Quality Certification 8-12
8.2.5 Findings - 8-14
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TABLE OF CONTENTS (CONTINUED)
Chapter Nine: Literature Cited 9-1
Chapter Ten: Glossary of Terms 10-1
Chapter Eleven: List Of Agencies, Organizations And Persons
To Whom The FEIR/S Has Been Sent 11-1
Chapter Twelve: Index
12-1
Volume 2
RESPONSES TO COMMENTS
Volume 3
APPENDICES
A Secretary's Certificate on DEIR/S
B. Transcripts of public hearings and meetings
C. List of Advisory Committee and Working Group Members
D. Treatment Technology Survey Questionnaire
E. October 1994 Sampling Reports (Fisheries, Benthics and Lobster)
F. Water Quality Modeling Report (ASA)
G. Bottom Velocity Profile of Prop Wash and Wave Induced Events
H. CA/T Landfill Capping Program Materials
I. Dewatering Study
J. In-Channel Sequencing Plan
K. Principal Valuable Functions (PVF) Report
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BOSTON HARBOR NAVIGATION IMPROVEMENT PROJECT
FINAL ENVIRONMENTAL IMPACT REPORT/STATEMENT
TABLE OF FIGURES
Figure 1-1. Massport and Non-Massport Properties in Boston Harbor
Figure 1-2. Port of Boston Container Activity
Figure 1-3. Boston Harbor Navigation Improvement Project General Plan
Figure 1-4. Boston Harbor Navigation Improvement Project General Plan
Figure 1-5. Navigation Improvement Project Reserved Channel
Figure 1-6. Navigation Improvement Project Mystic River
Figure 1-7. Navigation Improvement Project Chelsea Creek, Downstream of Chelsea
St. Bridge
Figure 1-8. Navigation Improvement Project Chelsea Creek, Upstream of Chelsea St.
Bridge
Figure 1-9.- Location of Federal Channel and Berth Area Dredging
Figure 4-1. Locations of Short-Listed Sites
Figure 3-1. Locations of potential disposal sites extensively evaluated.
Figure 5-1. Cu and Zn Concentrations 11 Yrs. After Placement: Interface at 80 to 100
cm
Figure 5-2. PAH Concentrations 11 Years After Placement: Interface at 80 to 100 Cm
Figure 5-3. Construction Sequence
Figure 7-1. Project Specific Designated Port Areas
Figure 7-2. Project Specific Designated Port Areas
xni
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BOSTON HARBOR NAVIGATION IMPROVEMENT PROJECT
FINAL ENVIRONMENTAL IMPACT REPORT/STATEMENT
TABLE OF TABLES
Table 1-1. Terminals and Docking Facilities
Table 1-2. Vessel Activity in the Port of Boston: Arrivals with Drafts Greater Than
18 Feet
Table 1-3. Trips and Drafts of Vessels Using Boston Harbor, 1960-1993
Table 1-4. Cargo Volume and Impact on Economic Benefit to the Port of Boston.
Table 1-5. List of Preparers
Table 2-1. Maintenance Dredging Projections for the Tributary Channels and the Main
Ship Channel
Table 2-2. Volume of Material Proposed for Dredging from Channels and Associated
Project Berths for the Boston Harbor Navigation Improvement Project
Projected Through 1997 (Dredge Volumes in Cubic Yards)
Table 3-1 . Potential Disposal Site Lists by Category Produced at the End of Each
Screening Phase
Table 3-2. Additional Information Collected for Nearshore Aquatic, In-Channel,
Borrow Pits, Subaqueous Areas and Existing Disposal Sites (October
1994).
Table 3-3 . Characteristics of Generic Disposal Alternatives
Table 3-4. Massachusetts Regulatory Guideline Levels of Dredged Materials for
Various Disposal Alternatives
Table 3-5. Evaluation of Suitability of Boston Harbor Navigation Improvement
Project Sediments for Various Disposal Alternatives
Table 3-6. Summary of Potential Site Preparation, Management Requirements for Use
of Generic Disposal Alternatives
Table 3-7. Potential Impacts from Silt Disposal at Generic Alternative Disposal Sites.
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Table 3-8. Impacts Caused by Using Specific Upland Sites for Boston Harbor
Dredged Material Disposal
Table 3-9. Potential Benefits of Dredged Material Disposal Alternatives
Table 3-10. Impacts Caused by Using Specific Aquatic Shoreline Sites for Boston
Harbor Dredged Material Disposal
Table 3-11. Potential Impacts Caused by Using Specific Subaqueous, Borrow Pit, and
In-Channel Sites for Boston Harbor Dredged Material Disposal
Table 3-12. Impacts Caused by Using Existing Open Water Disposal Sites for Boston
Harbor Dredged Material Disposal
Table 3-13. Alternative Disposal Options for Disposal of Silt Sediments
Table 3-14. Cost Estimates for Landfill Sites for BHNIP Silt Disposal
Table 3-15. Cost Estimates for Land-Based Sites for BHNIP Silt Disposal
Table 3-16. Cost Estimates for Aquatic Shoreline Options
Table 3-17. Cost Estimates for Subaqueous Depression Option for BHNIP Silt
Disposal
Table 3-18. Cost Estimate for In-Channel Disposal Options for BHNIP Silt
Table 3-19. Cost Estimates for Aquatic Borrow Pit Option for BHNIP Silt Disposal
Table 3-20. Costs for Alternative Treatment Technologies for BHNTP Dredged
Material
Table 3-21. Cost Estimates for Using Existing Aquatic Disposal Sites for BHNIP Silt
Disposal
Table 3-22. Companies Send Questionnaires for Information Treatment Technologies
for the Boston Harbor Navigation Improvement Project
Table 3-23. Technology Survey Questionnaire Responses
Table 3-24. Technology Rating Summary
Table 3-25. Ports Meeting Minimum Depth Requirements for Transfer of BHNIP
Material to Unlined Municipal Landfills
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Table 3-26. Screening Matrix for Determining the Least Environmentally Damaging
Practicable Alternative for Disposal of Silt from the BHNIP
Table 4-1. Summary of Impacts to BHNIP Land-Based Alternative Disposal Sites
Table 4-2. Comparison of the Size and Effect of Direct Impacts at BHNIP Alternative
Aquatic Disposal Sites
Table 4-3. Summary of Short-Term Water Quality Effects from Disposal at BHNIP
Alternative Disposal Sites
Table 4-4. Potential Sources of Site Destabilization That Could Arise During and/or
After Construction at BHNIP Alternative Disposal Sites
Table 4-5. Summary of Potential Impacts to Downstream Biological and Human Use
Resources from BHNIP Disposal Site Alternatives
Table 4-6. Summary of Relative Severity of Impacts of Potential BHNIP Aquatic
Disposal Alternatives
Table 4-7. Summary of Factors Affecting Practicability of Alternative Disposal Sites
Table 7-1. Acceptability Conditions for Activities with DPA's
Table 7-2. Normally Approval Dredging Handling and Disposal Options
Table 7-3. Factual Determinations
xvi
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I II II
HI
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BOSTON HARBOR NAVIGATION
IMPROVEMENT PROJECT
FINAL ENVIRONMENTAL IMPACT REPORT/STATEMENT
EXECUTIVE SUMMARY
Project Description
The Boston Harbor Navigation Improvement
and Berth Dredging Projects (BHNIP)
encompass the deepening of three tributary
channels (Reserved Channel, Mystic River
Channel and Chelsea Creek Channel) and
two areas in the Main Ship Channel (Inner
Confluence and the mouth of Reserved
Channel) to provide sufficient ship
maneuvering areas for the deepened
channels; six berth areas that would benefit
directly from the channel deepening (Conley
11-13, Prolerized, Distrigas, Moran,
Eastern Minerals and Gulf Oil); and six
berth areas and one intake structure that
would not benefit directly from (i.e., be
connected to) the channel deepening (Boston
Army, Boston Edison Intake, Boston Edison
Barge, Conley 14-15, Revere Sugar, Mystic
Piers 1,2,49 and 50). The President
Roads Anchorage Area and adjacent
channels would be re-marked to enlarge the
deep water anchorage without additional
dredging. Deepening of the channels to -40
ft MLW (except Chelsea Channel to -38 ft
MLW) would allow greater use of the
hitherto underutilized -40 ft MLW Entrance
Channel and Main Ship Channel (see Figure
ES-1).
The improvements to the three Federal
channels were proposed as a result of a
Feasibility Study completed by the Corps of
Engineers in 1988.. The three-channel
project was selected as the economically and
environmentally preferred project alterna-
tive. It was authorized by Congress in the
Water Resources Development Act of 1990
(P.L. 101-640). The authorized project
would allow the Port of Boston to maintain
its competitiveness in the highly competitive
national and international marine trade
business by reducing the cost of transporting
goods and thus improving efficiency.
Massachusetts Port Authority (Massport), as
local sponsor of the project, submitted an
Environmental Notification Form (ENF) to
Massachusetts Executive Office of
Environmental Affairs in April 1991. The
Secretary's Certificate on the ENF required
the preparation of an Environmental Impact
Report (EIR) with three major areas of
focus:
• sediment characterization,
• evaluation of disposal alternatives
and
• a dredging management
plan.
The Corps of Engineers, New England
Division, committed to preparing an EIS in
1992 due to the cumulative impacts of
Federal actions (maintenance dredging,
navigation improvement dredging, and
permitting of the associated berthing areas)
and the significant public concern over
disposal of dredged material. Because the
channel improvement and berth dredging
projects are intricately linked and
ES-1
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interdependent and would be reviewed by
the same regulatory audience, it was
determined that preparation of a joint
Environmental Impact Report/Statement
(EIR/S) would be most efficient.
A Draft EIR/S was published in April 1994.
This FEIR/S is designed to respond to
comments received on the Draft including
the Secretary's certificate dated June 30,
1994 and to comply with the requirements
for an FEIR as described in 301 CMR
11.07 (10). This document also serves to
meet the requirements for an FEIS as
specified in 40 CFR Part 1503. This
document identifies a preferred dredging
and dredged material disposal option,
assesses the anticipated environmental
impacts associated with each, identifies
potential long-term disposal options that
may be appropriate for maintenance
dredging of the completed project, and
responds to all comments received on the
Draft.
Purpose and Need of the Project
Both the MEPA and NEPA regulations
require a purpose and need statement that
briefly specifies the underlying objectives
and anticipated benefits of the project. The
purpose of the BHNIP is to increase the
navigational efficiency and safety of Boston
Harbor for present types of deep draft
vessels. This purpose was the basis for the
1988 Feasibility Report prepared by the
Corps to conclude that the project was
justified economically. There are also direct
economic benefits that accrue to the Port
from the BHNIP. These include: 1)
increased navigational efficiency and safety
by reducing the need to wait out tides or to
decrease loads prior to entering the Harbor;
2) the ability to ship more tons of
containerized cargo with fewer ships; 3) the
ability to attract new shipping lines; and 4)
ability to maintain vital refined oil products
facilities and allow for double-hulled
tankers.
Public Participation
Massport, the project's local sponsor, and
the Corps of Engineers recognized the need
to involve key agencies and groups in the
planning process through consultation,
information exchange and presentation of
diverse viewpoints. In March 1992,
Massport formally invited thirty-five
federal, state and local agencies and public
and private interest groups to participate in
a project Advisory Committee. The
Committee's function was to advise
Massport and the Corps of Engineers in the
overall design and planning of environ-
mental studies which would form the basis
of the environmental review. The
Committee met seven times over the course
of the studies leading to the preparation of
this EIR/S.
Early in the public participation process two
specific technical issues were identified as
those which would benefit from a more
focused analysis and review than that which
could be provided by the Advisory Com-
mittee. As a result, two Working Groups
were formed as subsets of the Advisory
Committee to provide guidance and
expertise in : 1) sediment characterization;
and 2) disposal site identification and
screening. Through the course of the
project these Working Groups, and the
larger Advisory Committee, provided
valuable commentary on sampling and
testing protocols and information on
identifying and characterizing disposal sites.
The Working Group process contributed in
creating a dynamic and responsive work
product by increasing the scope of the
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sediment sampling and testing and
expanding the types of disposal options and
specific disposal sites to be screened for the
project.
The Advisory Committee convened twice
during the preparation of the FEIR/S, in
September 1994 and March 1995. The
Advisory Committee was instrumental in
assisting the project team in identifying
major areas of concern regarding the
DEIR/S that required additional data
collection or analysis in the FEIR/S. These
consisted of a working group meeting in
November 1994, focusing on developing a
comprehensive data base of dredged
material treatment and disposal
technologies. A second working group
convened hi December 1994, focusing
dredging performance standards and
monitoring concerns that would be
developed into a comprehensive Dredge
Management Plan.
Public participation was also extended to
public meetings, meetings with concerned
interest groups, and the receipt of sixty-one
comment letters from federal, state, and
local agencies, commercial interests, private
interest groups and private citizens. Public
meetings were held hi Boston, Hyannis and
Nahant.
In addition to the public participation
process, the project team also engaged in
several meetings with the combined EOEA
agencies. Meetings were also held between
the Federal cooperating agencies and the
Corps to address Federal issues concerning
comments on the Draft EIR/S.
Sediment Characterization
The BHNIP will result in removal of
approximately 1.1 million cubic yards (cy)
of silt (as measured in-place). The total
quantity of silt requiring disposal is slightly
higher, 1.4 million cy, which accounts for
0.5 feet of over-dredging into the
underlying parent material and a 20%
expansion factor due to dredging. An
extensive sediment sampling and testing pro-
gram, developed interactively with the
Sediment Characterization Working Group,
was undertaken to characterize the dredged
material. The surficial silt layer (or
"maintenance" material) was found to
contain varying concentrations of metals,
polynuclear aromatic hydrocarbons (PAHs),
polychlorinated biphenyls (PCBs), and other
organics. The sediment bulk chemistry
data, in combination with test organism
toxicity and bioaccumulation testing,
indicated that the silt was generally
unsuitable for unconfined open water
disposal. It was further determined that the
underlying sediment (parent material) was
composed of clay and sand/gravel and has
low levels of metals and organics. The
Corps initially determined that
approximately 360,000 cy of silt was
suitable for ocean disposal. Using the same
data, however, the EPA determined that
none of the silt was suitable for unconfined
ocean disposal. In response, the Corps
adopted the more conservative position and
assumed that all silt from the project is
considered unsuitable for unconfined ocean
disposal.
The underlying parent material, composed
primarily of Boston Blue Clay with gravel
pockets, has been shown on this and other
projects to be uncontaminated and suitable
for unconfined open water disposal. The
total volume of approximately 2 million cy
of parent material (including the expansion
factor) can be disposed at an unconfined
open water site if no beneficial uses (e.g.,
landfill and/or capping) are identified. The
final component of the dredged material is
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rock that would be removed from Mystic
River Channel and two areas of the Main
Ship Channel. Beneficial uses considered
for the 132,000 cy (post-dredging volume)
of rock included habitat enhancement or
armoring disposal sites that are subject to
high-energy hydrodynamics.
In addition to addressing the dredged
material disposal needs for the BHNIP
itself, disposition of the future maintenance
of the deepened channels over the 50 year
project life was addressed. The estimated
4.4 million cy of future maintenance
material would be composed primarily of
silt. For the purpose of the disposal
alternatives analysis, it has been assumed
that this material could contain elevated
levels of contaminants. Under this
assumption (which may or may not be the
case), the material would have to be depos-
ited in a confined disposal site.
Disposal Alternatives Analysis
A Disposal Options Working Group was
convened to develop criteria for evaluation
of the universe of potential disposal sites
and beneficial uses of parent material, rock,
silt and future maintenance dredging
material. The group participated in the
disposal site selection process at regular
intervals, reviewing arguments for retaining
or eliminating specific sites. The short list
of potential disposal alternatives included
sites in two major categories, land-based
and aquatic sites, and eight subcategories:
landfills, land-based inland, land-based
coastal, aquatic shoreline, aquatic
subaqueous, aquatic borrow pit, existing
aquatic disposal sites, in-channel disposal
and treatment technologies.
The disposal alternatives analysis screening
process was comprised of four phases. In
the first phase, comparisons were made
using evaluation criteria among sites within
each alternative category (i.e., landfills were
evaluated together but not compared to
aquatic shoreline sites). A subsequent
evaluation focused on regulatory and other
limiting criteria to select the sites which
provided the least environmental impact
with the greatest project benefit. Sites were
then screened for practicability issues of
cost, logistics and technology in relation to
project needs and goals.
In response to comments on the DEIR/S,
the site screening process was re-visited.
Additional data collection activities,
performed after publication of the DEIR/S,
were used to-upgrade the data base upon
which the sites would be evaluated. A
confirmatory aquatic sampling program was
undertaken in October 1994 to assess fin
fish, benthic and lobster resources at the
aquatic disposal sites. Fate and transport
modeling to determine sediment load and
contaminant transport was performed for all
aquatic disposal options. In addition, agency
files and resources were used to update and
upgrade the information on the land-based
sites. This fourth-phase screening process
narrowed the list of practicable alternatives
from an initial list of 376 sites and eight
treatment technologies to 24 sites.
The development of disposal options next
focused on combining sites to meet the
capacity requirements of the project. This
evaluation emphasized the fact that few sites
are large enough to accommodate the
disposal needs of the BHNIP by themselves.
Finally, an environmental and practicability
evaluation of options led to the identification
of the in-channel disposal option. This
option disposes of silt within the dredging
footprint of the Mystic and Chelsea Rivers
and the Inner Confluence in cells
constructed in the parent material that are
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capped with sand after filling. The in-
channel option resolves concerns expressed
on the DEIR against a "monofill" site by
combining three sites (the Mystic and
Chelsea Rivers and the Inner Confluence
Area), confines impacts to the dredging
footprint, and is rated the least
environmentally damaging practicable
alternative (LEDPA).
In response to agency comments on the
DEIR/S, the project team has been asked to
identify a secondary preferred alternative
site for excess silt capacity should the
preferred alternative fail to provide
sufficient capacity after the project is
underway. Based on the environmental and
practicability screening process mentioned
above, the Little Mystic Channel has been
identified as a secondary contingency site.
This site would be filled to mean low water,
changing approximately 15 acres from a
subtidal, but degraded condition, to
intertidal habitat with clean substrate. This
option provides approximately 373,000 cy
of contingency capacity. If this site is
required for secondary capacity, mitigation
for change hi substrate will be discussed
with the appropriate resource agencies.
Parent material, not expended through a
beneficial use, would be disposed at the
MBDS. Rock will be available to cap the
in-channel locations that may be subject to
impacts from propeller wash, or it will be
made available for another beneficial use.
The remaining rock will be disposed of at
the MBDS.
The FEIR/S also provides a disposal site
selection process for maintenance dredging
over the 50-year life of the project, or the
maintenance material dredged even if the
proposed navigation improvement project is
delayed or not implemented. Maintenance
dredging of accumulated silt material will be
needed to allow ships to transit the harbor
safely. Unlike the navigation improvement
project, maintenance dredging would not
produce clean parent material which could
be used for capping. Therefore, disposal
options which provide cap material, such as
the Meisburger sites and Spectacle Island
CAD, are preferable. Disposal could occur
at other sites if suitable cap material can be
found from other projects. The use of an
aquatic site for maintenance dredged
material would be subject to a lengthy site
designation process. The Corps may be
performing a demonstration of capping
when suitable material becomes available so
that the Massachusetts Bay Disposal Site can
be used for maintenance material.
Effects of the Project
Certain short-term adverse effects of the
project would be unavoidable. Some
benthic organisms and demersal fish would
be killed during dredging and blasting.
Substrate in the areas dredged would be
temporarily devoid of benthic organisms but
would be recolonized in approximately one
year, reforming habitat with prey suitable
for fin fish. Turbidity would increase
temporarily in the area of the dredge. Use
of an environmental (closed) bucket will
help minimize contaminant release. Other
turbidity controls, such as silt curtains, will
be assessed in terms of suitability depending
on the location of the dredging operation.
Close monitoring of the dredging
operations, to identify problems and quickly
seek corrective measures, will be
undertaken.
The anticipated dredging rate would
generate approximately two to four barges
per day, depending on whether one or two
dredges were operating and the size of the
barges. Thus barge traffic should not
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noticeably impede normal ship traffic;
interference with navigation would be
minimized by coordination with the Coast
Guard.
Impacts due to disposal of dredged materials
are temporary since they do not permanently
alter the substrate of the in-channel areas.
Also, in-channel disposal impacts remain
within the footprint of the dredging so that
resource areas outside the navigation
channels are not impacted except for
temporary turbidity impacts.
During the 116 to 2 year dredging process
non-motile faenthic organisms utilizing the
disposal areas would be buried.
Recolonization should occur within one year
after disposal operations are completed
based on the existing benthic population of
early successional stage organisms. Fin fish
would tend to avoid the area during disposal
due to noise and turbidity disturbances. The
benthos and fish would eventually recolo-
nize the dredge site and will benefit from
the removal of contaminated silts.
Important anadromous fish populations
would be protected by suspending dredging
and disposal in the Mystic River during the
migration season.
The water column in the vicinity of the
disposal site would experience increased
turbidity following each disposal event.
Approximately three to five percent of the
silt/clay fraction would be lost to the
environment during the disposal descent
phase. Disposal simulation model
evaluations indicated that disposal will not
cause adverse exposure (i.e., exceedances of
water quality criteria). The contaminant
mixing zone, based on Total Suspended
Solids (TSS) and PCB loads, has been
calculated based on fate and transport
modeling and will not interfere with fish
passage and migration. Use of mitigation
measures, such as silt curtains, to contain
suspended solids and associated chemicals,
are proposed as additional safeguards to
minimize water quality impacts in the
Harbor.
Secondary impacts of the project, consisting
of land-side infrastructure impacts, Harbor
traffic, and other socioeconomic interests,
are minimal. The BHNIP will not
significantly increase vessel traffic in the
Harbor but will enhance navigational safety
and maintain the competitiveness of the
existing Port. Vessel traffic will continue to
include a mix of large container ships,
barges and tankers. The Seaport Access
system, which is part of the Central
Artery/Tunnel project, will result in more
direct and convenient connections for trucks
between port terminals and the regional
highway network, thereby reducing traffic
impacts on local neighborhoods. This
roadway system is independent of the
dredging project.
Dredge Management Plan
The FEIR/S has addressed the requirement
for a Dredge Management Plan (DMP), as
requested in the MEPA Scope. The DMP
provides an overview of the dredging
operations proposed for the project The key
elements of the Plan include:
• a description of alternative dredging
equipment and specific
recommendations for this project;
• a description of dredged material
disposal operations;
• a discussion of the sequencing of the
dredging and disposal operations;
• an overview of potential
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environmental impacts caused by
these activities;
proposed techniques for mitigating
operational impacts;
establishment of dredging
performance standards;
a description of recommended
monitoring plans during dredging
and for long term post-construction
monitoring;
and a discussion of potential
operational contingency plans that
would be implemented to assure the
safe and successful completion of
the project.
Cumulative Impacts
Cumulative impacts include all long-term
maintenance requirements of the BHNIP in
association with reasonably foreseeable
long-ranged material disposal issues. These
impacts also consider other actions in the
Boston Harbor area that may have an impact
on, or be impacted by, the project.
Selection of disposal sites for future
maintenance dredging will be based on the
environmental and practicability assessments
provided hi the MEPA/NEPA
documentation. Factors affecting
maintenance dredging sites include sediment
characteristics and volume of material to be
dredged. Sites that require site designation
status, because of their capacity for
numerous projects, would require lengthy
permitting and detailed environmental
assessment. Fast-track projects would have
to. look elsewhere for disposal. The
disposal site for future maintenance of the
BHNIP, and other Massachusetts projects,
will be determined based on the appropriate
environmental regulations and technical
evaluations at that time. The New England
Division Corps recommends, and will
participate with the Commonwealth, hi
conducting an overall regional dredge
material management plan for future
maintenance of all of the Massachusetts
Bay's harbors.
Two other large projects are currently under
construction in Boston - the Deer Island
wastewater treatment facilities upgrade and
the Central Artery/ Third Harbor Tunnel
(CA/T). The level of ship traffic generated
by the BHNIP, its location relative to the
Deer Island and CA/T projects, and the
anticipated schedules for the three projects
should result in minimal conflicts among the
projects. The Massachusetts Highway
Department expects that the placement of
Third Harbor Tunnel excavate at Spectacle
Island will be complete in 1995. As with
other harbor infrastructure, coordination
with the construction of the Third Harbor
Tunnel would have to be carefully
orchestrated. The BHNIP is expected to
commence in 1997 and be completed in
1998. Coordination of ship traffic from
each project with the U.S. Coast Guard will
provide further safeguards. The Massachu-
setts Water Resources Authority (MWRA)
anticipates substantial completion of the
Deer Island plant upgrades by late 1995.
Water quality (and ultimately sediment
quality) would continue to improve with the
operation of MWRA's secondary treatment
and offshore disposal facilities. The BHNIP
and future maintenance dredging would
continue to reduce the mass of contaminants
in Boston Harbor even further.
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Summary of Major Changes
from the DEIR/S
Several issues were raised during the
comment period that resulted in substantive
changes from the proposed list of disposal
alternatives presented hi rne DEIR/S. These
issues were resolved as follows:
• Based on applicable environmental
screening criteria, all silts generated
by the project are considered
unsuitable for unconfmed ocean
disposal.
• The MBDS, Subaqueous B and E,
Meisburger 2 and 7, Boston Light
Ship, and Spectacle Island CAD,
have been eliminated from further
consideration as practicable disposal
sites for the BHNIP silt. These sites
are still being considered as
potential disposal locations for
future maintenance dredging. Use
of these sites for future disposal may
require additional studies,
demonstration projects, site
designation, or the application of
appropriate technologies.
• All parent material, consisting of
sand/gravel, clay and rock,
generated by the project is
considered suitable for disposal at
MBDS or for beneficial re-use,
including use as a potential source
of capping material for unlined
municipal landfills.
• Technologies will continue to be
assessed by the Corps for their
potential applicability to future
maintenance dredged material.
Cost considerations and capacity are no
longer considered to be fatal flaws in
disposal site screening. Cost is factored in
only to assess the relative cost-effectiveness
of disposal scenarios determined to be
environmentally suitable and to determine
practicability. Capacity is only one factor
considered in site screening and
combinations of sites of limited capacity
may constitute acceptable disposal scenarios.
Federal and State Review
This FEIR/S will be reviewed by regulatory
and resource agencies on the federal, state
and local levels, as well as other interested
parties for adherence to MEPA and NEPA
guidelines and for addressing the issues
raised in comment letters, at public
hearings, and in the Secretary's certificate
on the DEIR/S. Comments on this FEIR/S
will be accepted by either the MEPA Unit at
the Executive Office of Environmental
Affairs or by the U.S. Army Corps of
Engineers, New England Division. It is
anticipated that the public comment period
will be open until July 31,1995.
Commentors are advised to contact these
agencies directly to determine the actual
date for the close of the comment period.
Federal and state permits and consistency
reviews ultimately required for the project
potentially include:
• U.S. Army Corps of Engineers
- Section 10 of the Rivers
and Harbors Act
- Section 404 of the Clean
Water Act
• National Marine Fisheries Service,
U.S. Fish and Wildlife Service
- Endangered Species Act/
Section 7 consultation
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U.S. Environmental Protection
Agency
- Section 404 and
Endangered Species Act
consultation
Massachusetts Department of
Environmental Protection
- Water Quality
Certification
- Division of Wetlands
and Waterways review
of local Order of
Conditions
Massachusetts Office of Coastal
Zone Management
- Coastal Zone
Consistency Review
local Conservation Commissions)
- Order of Conditions
Format of the FEIR/S
This FEDR/S is comprised of three volumes.
The fkst volume contains the main text and
consists of:
• The procedural history, and purpose
and need, of the project (Chapter
One);
• A detailed project description and
comparison of design alternatives
(Chapter Two);
A summary of the detailed process
for screening sites for material
disposal (Chapter Three);
The environmental and practicability
screening of a short-list of
alternatives to determine the Least
Environmentally Damaging
Practicable Alternative (LEDPA)
(Chapter Four);
• A detailed dredged management
plan to describe the dredging and
disposal operations and appropriate
mitigation and contingency measures
(Chapter Five);
• Mitigation concepts and proposals
summary and opportunities for
resource enhancement (Chapter Six);
• An assessment of the permitting and
regulatory requirements the project
must meet (Chapter Seven);
• A draft Section 61 finding to meet
Massport obligations under 301
CMR 11.00 (Chapter Eight).
• A list of technical literature cited hi
this FEIR/S and a bibliography of
references on Corps capping
experience (Chapter Nine).
• A glossary of technical terms
(Chapter Ten).
Attachment 1 to this volume contains
detailed descriptions of the affected
environment and project related impacts at
the short-listed alternative sites.
Volume Two of the FEIR/S provides a copy
of all comment letters received on the
DEIR/S followed by a detailed response to
each. Volume Three consists of appendices
referenced throughout this FEIR/S.
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35' chann8'
EAST BOSTON
CHARLESTOWN ',
inar and Callahan Tunnels
;• ;
^ , ^-MBTA Tunnel
t v;
,.' ..% •• ''
US Army Corps of Engineers
New England Division
Boston Harbor,
Navigation Improvement Project
Figure ES-1 ' '""
Deepen
To -40' MLW
To -38' MLW
Existing Channel
Realigned Channel
(President Roads)
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III Ill 1 II III
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Chapter One: Introduction
This document constitutes a joint
Commonwealth of Massachusetts Final
Environmental Impact Report and Final
Environmental Impact Statement (FEIR/S)
prepared by the Massachusetts Port
Authority (Massport) and the U.S. Army
Corps of Engineers (Corps). As a joint
document, this FEIR/S meets the .
requirements of both the Massachusetts
Environmental Policy Act regulations (301
CMR 11.00 el. seq.) implemented by the
MEPA Unit of the Executive Office of
Environmental Affairs, and the National
Environmental Policy Act regulations (40
CFR Parts 1500 - 1508) also known as
NEPA.
This document pertains in part to the
Corps' Navigation Improvement and Berth
Dredging Projects. These Projects were
authorized by Congress in the Water
Resources Development Act of 1990 (P.L.
101-640). This document also pertains to
Massport in its role as local sponsor of the
Federal project and for its planned berth
dredging activities.
The MEPA regulations establish
environmental review thresholds, a
procedure, and a timetable for a two-level
review process. The process generally
begins when the project proponent, in this
case Massport, files an Environmental
Notification Form (ENF) with the
Secretary of the Executive Office of
Environmental Affairs (EOEA). Upon
review of the ENF, the Secretary
determines whether an Environmental
Impact Report (EIR) is required for the
project. The Secretary determined that the
Massport project required an EIR in a
certificate issued on June 7, 1991. An
EIR is an informational planning document
which serves to inform public decision
makers, and the general public, of the
environmental effects of the proposed
project. As a planning tool, an EIR
enables both the project proponent and
agency decision makers to weigh
environmental impacts and benefits prior
to making decisions on permits, approvals
or funding. The EIR is reviewed and
commented on, at both draft and final
stages, by agencies, the public, the MEPA
Unit, and the Secretary. The Draft EIR
was published in April 1994. This FEIR/S
is designed to respond to comments
received on the Draft including the
Secretary's certificate dated June 30, 1994
(see Appendix A), and complies with the
requirements for a Final EER as described
in 301 CMR 11.07(10).
The final component for MEPA
compliance is the required review and
evaluation of projects to determine whether
all feasible means and measures will be
used to avoid or minimize damage to the
environment. This last step is a process
generally referred to as a "Section 61
finding" and is required by M.G.L. c.30,
§ 61. No agency may act on a permit or
commence a project until this finding is
complete. The Draft and Final EIRs serve
as the substantive bases for the Section 61
finding, and as such, the FEIR may
contain a proposed finding (301 CMR
11.07(10)). This FEIR therefore, contains
Massport's Draft Section 61 finding. The
Department of Environmental Protection
(DEP) is also required to submit its own
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finding prior to issuing permits and
approvals for the project.
Similarly, the Federal NEPA process is
designed to insure that environmental
information is available to public officials
and citizens before decisions and actions
are taken by Federal agencies. A federal
agency's decision to prepare an
Environmental Impact Statements (EIS)
under NEPA based on the magnitude of
the project, the similarity of the project to
others which normally require an EIS, or
if the nature of the project is one without
precedent (40 CFR §1501.4). For this
project, the U.S. Army Corps of
Engineers, New England Division (Corps)
is the lead federal agency for the EIS.
Scoping of the EIS is based on the
participation of affected federal, state and
local agencies and interested persons in
public scoping sessions. Scoping sessions
were held in June 1992 for the Boston
Harbor project.
Draft EISs are prepared in accordance with
the scope derived from the scoping
meetings and must meet the format
requirements of 40 CFR Part 1502.10.
Final EISs must also respond to comments
received on the Draft. Following the
review of all comments received on the
Draft EIS, and the review of comments
received on the Final EIS, the lead federal
agency must review all relevant
information and must consider all
alternatives described in the EIS in order
to render a decision on the proposed
action. At the time of its decision, the
lead agency must prepare a concise
"record of decision" or ROD, identifying
all alternatives considered by the agency in
reaching its decision and specifying the
alternative considered to be
environmentally preferred. The ROD
must also state whether all practicable
means to avoid or minimize environmental
harm have been adopted, and if not, why
they were not.
This document serves to meet the
requirements for a Final EIR/S as specified
in 301 CMR 11.07(10) and 40 CFR Part
1503. This document identifies a
preferred dredging and dredged material
disposal option, assesses the anticipated
environmental impacts associated with
each, identifies potential long-term disposal
options that may be appropriate for
maintenance dredging of the completed
project and responds to all comments
received on the Draft.
The MEPA and NEPA processes, while
different, require substantially similar
environmental analysis and documentation
of proposed actions. Because of this
similarity in substantive material, and
because regulatory agencies and the public
would be simultaneously reviewing both
the EIR and EIS produced for the project,
Massport and the Corps elected to file a
joint EIR/EIS. The combination of the
two documents is specifically provided for
in 40 CFR 1506.2 (c). As stated earlier,
the Draft EIR/S was published in April
1994.
There are further opportunities for public
review and comment on the proposed
action. Under MEPA, a notice of
availability of the FEIR is published in the
Environmental Monitor. This notice is
followed by a thirty day comment period,
after which the Secretary of the EOEA
issues a statement indicating whether or
not the FEIR adequately and properly
complies with the provisions of the MEPA
regulations. Public comments on the FEIS
may also be received and reviewed by the
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Corps under NEPA and are considered in
the preparation of the ROD. Readers who
wish to offer comment on this document
are advised to contact Ms. Nancy Baker at
the MEPA office (617-727-5830) or Mr.
Larry Rosenberg at the U.S. Army Corps
of Engineers (617-647-8657) for the dates
that the respective public comment periods
close. It is anticipated that public
comments will be accepted through July
31, 1995. However, individual MEPA or
NEPA procedural requirements may affect
this closing date.
Lastly, the proposed project will require
federal, state and local permits and
approvals. The MEPA and NEPA
documentation will provide a substantial
basis for the permit applications. The
administrative procedures for acquiring the
various permits and approvals also
provided opportunities for agency and
public comment. Permits from
Massachusetts agencies cannot be issued
until the MEPA process is closed by the
Secretary's certificate and the preparation
of a Section 61 finding by the issuing
agency. Federal agencies are also barred
from issuing federal permits until the
NEPA process is complete and a ROD has
been issued for the project. Chapter 7 of
this FEIR/S describes the permits that will
be required to undertake the proposed
action.
Both the MEPA (301 CMR 11.07(3)) and
NEPA (40 CFR § 1502.13) regulations
require a purpose and need statement that
briefly specifies the underlying objectives
and anticipated benefits of the project.
The next section provides the underlying
purpose and need for the BHNIP and the
economic benefits expected to accrue from
its completion.
1.1 PROJECT PURPOSE AND NEED
The purpose of the Boston Harbor
Navigation Improvement Project (BHNIP)
is, as stated in the DEIR/S, "to increase
the navigational efficiency and safety of
Boston Harbor for present types of deep
drafted vessel traffic..." The BHNIP will
thereby enable the Port of Boston to
remain competitive with other ports in the
national and international marine trade
business.
The existing Federal navigation project
was originally constructed to serve the
port's commercial terminals located along
the main ship channel waterfront.
Changing waterfront land use patterns have
resulted in most of the port's active
terminal facilities shifting from the Main
Channel to the -35 foot MLW tributary
channels. The BHNIP will provide for
improvement dredging in the tributary
channels to accommodate the current
vessel fleet to a depth of -40 feet MLW.
The BHNIP as proposed is comprised of
three dredging components:
1. Deepening the Mystic River and
Reserved Channel areas to -40 feet
MLW and deepening the Chelsea
River to -38 feet MLW.
2. Deepening portions of the Inner
Confluence area, as well as the
Main Ship Channel at the mouth of
the Reserved Channel, to provide
for increased areas for navigational
maneuvering.
3. Dredging associated beneficiary
and related berths.
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The various elements of the proposed
action are described in detail in Chapter
Two. The economic analysis compiled by
the Corps, and contained hi the 1988
Feasibility Report, concluded that the
project is justified economically by
increasing navigational efficiency. The
BHNEP will address the Port's need to
allow passage of more efficient, larger
vessels which will transit the Harbor
during a wider range of tidal stages. The
BHNEP will enable the Port of Boston to
accommodate the current fleet of container
ships, with drafts up to -40 feet MLW,
cruise ships, such as the QBE with a draft
of -37 feet MLW, and the Chelsea-class
tankers, which draw 36 feet.
Improving the tributary channel and berth
depths hi Boston Harbor will be the port's
first major dredging project since 1982/83
when 867,000 cy of dredged material was
removed from the Mystic River, Chelsea
Creek and President Roads. The only
additional dredging projects completed
since that lime have been small volume
projects for maintenance of individual
berths.1
1.1,1 Historical Importance of the Port of
Boston
Boston has a long and colorful maritime
history. The Port has provided jobs and
economic opportunity for residents for
1 Some examples of recent dredging projects
include the Mobil Oil Corp. terminal berth in
the Chelsea Creek (approximately 1,500 cy) in
1991; Coastal Oil Corp. terminal berths in the
Chelsea Creek and Reserved Channel
(approximately 3,000 cy in 1992); and Moran
Terminal in the Mystic River (approximately
10,000 cy in 1993)
over three hundred years. It has created
fortunes in foreign trade and commerce for
residents of the region. Because of a
renewed interest in Boston Harbor with its
commercial, recreational, scenic and
commuter transportation offerings, more
people are spending tune there.
Today, the Port looks different from the
images taken from earlier years when
commercial traffic in the Harbor was
heavy and terminal berths, which lined the
waterfront, were always occupied by
commercial vessels. Table 1.1 lists the
terminals and docking facilities operating
in Boston Harbor today which have been
expanded to serve commercial,
recreational, tourist and commuter traffic
that now occupies the Harbor. Figure 1.1
depicts these docking facilities that have
industrial port terminals alongside cruise
ship terminals, and commuter and
excursion boat docks. Boston Harbor
hosts sailboat races alongside the huge
container ships transiting the Harbor to
reach marine terminals.
The importance of the Port to the Greater
Boston metropolitan area and to the region
remains vital." Over the years, it has
consistently allowed the region to
capitalize on its location, one day closer to
Europe than other major U.S. ports.. This
has been advantageous for three centuries
when the bulk of trade was with North
Atlantic countries. The Port now has the
potential to be a U.S. gateway for trade
with the rapidly growing countries in
Southeast Asia, but only if its 40-foot
depths are maintained.
1-4
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1.1.2 Economic Benefits of Project
The economic benefits of the BHNIP
project can be summarized as follows:
1. Increased navigational efficiency
by reducing the need to wait out
tides or to decrease loads prior to
entering the Harbor;
2. Ability to ship more tons of
containerized cargo with fewer
ships;
3. Ability to attract new shipping
lines;
4. Maintain navigational safety of
vital refined oil products facilities.
Each of these benefits are described
inthefollowing paragraphs:.
1.1.2.1 Navigational Efficiency
Changes in the world wide shipping fleet
have occurred in response to the need to
minimize vessel operating costs and as a
result of governmental regulations. While
larger vessels are more costly to operate,
they can move much more cargo on a
given trip thereby lowering the cost per
unit of cargo. In the highly competitive
maritime industry, ports without ample
depth cannot attract the new fleet of
vessels. The cost to operate today's
ocean-going vessels is too high to support
unproductive time waiting for tide changes
or traveling at less than full loads. As an
example, Massport notes that it can cost
$35,000 per day to operate a container
ship. The 40-foot depth of Boston's main
navigation channels and the proposed depth
of -40 feet MLW hi two of its tributaries,
and -38 feet in Chelsea Creek will enable
these large ships to move through the
Harbor.
Alternately, if there is no dredging project
and shipping lines still must wait for the
high tide, the Port is likely to see a
reduction hi direct calls. This could
discourage shippers who object to the
added cost and extra tune required for
lightering to barges or overland
movements. These shippers will seek out
more direct shipping opportunities.
Equally important is mat without
improvement dredging, there could be a
reduction hi cargo volume moving through
the Port which translates into economic
loss to the region.
1.1.2.2 Containerized Cargo Volumes
The number of deep-drafted vessels calling
in the Port of Boston may have diminished
over the years, as shown on Table 1.2, but
larger vessels can now carry a greater'
volume of cargo. In 1975, for example,
272 fully containerized vessels called with
some 400,000 tons of cargo. In 1994, 198
vessels called with over 1,313,000 tons of
cargo (see Table 1-3 which identifies deep
draft vessels by type of vessel, and Figure
1-2, which shows the volume of
containerized cargo coming through the
Port).
The magnitude of potential gams and
losses depending on a decision about
dredging is shown on Table 1-4. The
table assumes that the dredging project is
completed hi i998 and that cargo tonnage
increases at the rate of 3% for a total of
1,514,200 tons in that year. That tonnage
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yields about $1.73 billion in value
including 13,000 total jobs in the region.2
Using what Massport considers to be a
conservative growth rate, 3% annually, for
the volume of cargo coming through the
Port, the table shows that the total new
cargo volume will be over 241,000 tons at
the end of five years.3 The economic
benefit of the additional tonnage will be
over $277 million (not discounted to 1995
dollars). This represents almost 1,900
new jobs. The BHNIP enables this growth
to occur by ensuring that vessels can
transit the Harbor with a minimum of
delay.
1.1.2.3 Ability to Attract New Shipping
Lines.
On the other hand, news of a No-Action
decision on dredging Boston Harbor will
affect the decisions of shipping lines and
shippers, since navigational delays and
restrictions will continue, and will likely
decrease the volume of cargo coming
through the port. Once the decline in
tonnage begins, it will be difficult to turn
around. The fixed costs to operate the
port for diminishing cargo volumes could
eventually prove too high to operate cost-
effectively.
Without dredging, the Port of Boston
potentially loses the direct calls, with the
accompanying loss of tonnage moved
through the port. Table 1-4 shows that
with annual declines of 1%, 3%, or 5% hi
cargo tonnage, losses in benefits to the
region over a five year period, range from
$85 million to $392 million. Job losses hi
the port community could be anywhere
from about 580 to 2,700 during that time.
This is for containerized cargo, alone.
Cruise ships, currently drawing 25-37 feet,
also need convenient access to berths to
sustain this industry which has brought
additional tourism to the region.4
1.1.2.4 Maintain Refined OH Product
Capacity
The BHNIP is especially important to the
region because it keeps the Port of Boston
open to supply the region's growing
energy needs. Without refineries of its
own, New England's refined oil products
must be brought in from the Mid-Atlantic
states or the Southwest, or imported from
abroad. Most of the product arrives
through ports, and the Port of Boston is a
dominant player in this arena.5 Vessels
carrying petroleum products are also
.getting larger to minimize.operating costs
per gallon. The" size of vessels also is
increasing hi response to the mandate for
double-hulled tankers pursuant to the Oil
Pollution Act of 1990. New tankers may
have the same carrying capacity as the old
ones, but will draw more because of the
double-hull and will be wider.
2 Massport calculates economic impact to the
region of each ton of cargo is $1,120.
3 Massport internal memorandum, "Marketing
Projections of Container Volumes and Vessel
Calls, January 13, 1995.
4 Massport data indicates that 23 cruise ships
called in 1993, 49 called in 1994.
5 Massachusetts Division of Energy Resources
Report, March 1992.
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When the "Chelsea-class" vessels, which
currently operate in the port and draw 36
feet, retire, the new vessels coming on line
to replace them will be larger and will
require more depth since Chelsea-class
vessels are no longer financially viable to
operate. The newer vessels will be
restricted by two factors:
1. Tides - Insufficient depth at mean
low water requires vessels to
partially unload or "lighter" the
vessels prior to entering the
Harbor. The lightering process
entails pumping product from the
vessel to a barge. It is inefficient
because it requires the double-
handling of product.
2. Day light hours - The wait for high
tide can be especially costly for
vessels bound for Chelsea Creek
since the Coast Guard prohibits
vessels measuring more than
630.5' hi length and 85.5' hi beam
from transiting the "marine safety
zone" hi Chelsea Creek between
sunset and sunrise. Maintaining a
schedule for accessing berths in
Chelsea Creek can be difficult,
especially hi whiter, given the need
to have both high tide and
daylight, and given the few hours
of daylight hi whiter.
Each fuel company has its own method for
calculating the cost to "lighter". While the
transfer of product may cost 0.5 cents per
gallon, that figure does not include the cost
of delay to a vessel during the lightering
operation. The cost of the delay depends
on the amount of product requiring
transfer. While there is no definitive
figure for the cost of lightering hi the Port
of Boston, recent analyses have suggested
4-4.5 cents per gallon as a cost attributable
to lightering in the Ports of Providence and
New Haven. This cost is generally passed
on to the customer. Given the
inconvenience currently posed by
lightering and delays for high tide, the
BHNIP will hi general, facilitate
movement of cargoes through the Port,
minimizing the frequency
of those procedures and increase the
margin of safety for those vessels currently
operating hi the Port.
PROCEDURAL HISTORY
The publication of this FEER/S is the
culmination of many years of analysis and
review. Since the publication, -of the Draft
EIR/S hi April 1994, the project proponent
and the Corps have had close coordination
with state and federal agencies on all
aspects of the Project. The following
pages outline the procedural history and
development of this document and the
coordination efforts of the project partners.
•1.2.1 Congressional Authorization
The genesis of the Boston Harbor dredging
project can be traced back to 1968 when
Congressional and local interests expressed
the need for modifications to Boston
Harbor channels because of tke increased
traffic hi bulk commodities flowing
through the port, and the delays being
experienced by larger vessels requiring a
high tide to negotiate the existing restricted
ship channels into areas of the port. Local
navigation interests, via two Congressional
Resolutions (March 1, 1968 and September
11, 1969), requested the Corps review the
present and projected navigation needs hi
1-7
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Boston Harbor. The Corps maintains the
authority to conduct General Investigations
into improving the navigability of waters
of the United States tinder the River and
Harbors Act of 1899.
A Feasibility Report and Environmental
Assessment was completed in 1988 by the
U.S. Army Corps of Engineers for the
navigation improvement project,
identifying the economically and
environmentally favored alternative.
Congressional authority for the project was
included in the Water Resources
Development Act of 1990 (P.L. 101-640).
The favored alternative "consisted of
deepening the Mystic River and Reserved
Channel from -35 feet to -40 feet MLW,
and the Chelsea Creek from -35 feet to -38
feet MLW. The 1988 favored alternative
also included dredged material disposal at
the MBDS, with capping of unsuitable
material. In addition to the proposed
deepening, the favored alternative called
for modifications in the Mystic River, the
Inner Confluence and at the entrance to
Reserved Channel to provide safe
maneuvering areas. Finally, in the
President Roads area, channels are to be
remarked and designated along the
southern reach of the roads connecting the
outer confluence of the three entrance
channels with the inner harbor Main Ship
Channel. This will enlarge the anchorage
area from about 375 acres to about 420
acres. This portion of the Congressionally
authorized proposed action is termed the
"improvement" project.
Six berth areas adjacent to these channels
(Conley 11-13, Prolerized,-Distrigas,
Moran, Eastern Minerals and Gulf Oil),
deepened to at least the same depth as the
channel, would realize the greatest
economic benefits from the
"improvement" project. Deepening these
berths is termed the "berth dredging"
project and these selected berths are
collectively termed "beneficiary" berths.
The 1988 Corps feasibility study assessed
the economic feasibility of the proposed
"improvement" and "berth dredging"
projects and found that the regional
benefits of the project exceeded project
costs.
In addition to the beneficiary berths, other
berths within Boston Harbor, but not
adjacent to the Federal project channels
being improved (Boston Army, Boston
Edison Intake, Boston Edison Barge,
Conley 14-15, Revere Sugar, Mystic Piers
1,2, 49 and 50), would also be deepened at
the same time as part of Massport's Berth
Dredging Project. Bom the Corps
improvement and berth dredging projects,
and Massport's berth dredging projects,
are collectively termed the Boston Harbor
Navigation Improvement Project (BHNIP).
There are two main differences between
the Congressionally authorized proposal
and the BHNIP. First, under the BHNIP
dredged silts will not be disposed of at the
MBDS, unlike the 1988 proposal. It is
now proposed that silts be disposed within
the dredging footprint of the authorized
channels in trenches excavated for mat
purpose. Although this will entail digging
portions of these channels deeper than
authorized for the navigation project, this
is permissible because the extra depth is
for disposal, not navigation.
Second, the non-beneficiary berths (those
not adjacent to the federal improved
channels) were not included in the 1988
proposal but are considered part of the
BHNIP. The term BHNIP will be applied
to all aspects of the Corps and Massport
projects and will be treated as one
throughout this document except where
otherwise noted. The locations of
1-8
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proposed dredging activities are shown on
Figures 1-3 through 1-9.
1.2.2 Public and Agency Review
As stated earlier, the BHNIP is subject to
review under the Massachusetts
Environmental Policy Act (MEPA)
(M.G.L. c. 30 § 62A-H and regulations
promulgated thereunder at 301 CMR
11.00). The Secretary of Environmental
Affairs determined on June 7, 1991, that
an Environmental Impact Report (EIR) is
required since the Massport berth dredging
project involves the dredging and alteration
of ten or more acres of resource area
protected by the wetlands regulations (310
CMR 10.00). In June 1992, the U.S.
Army Corps of Engineers determined that
an EIS is required for the federal project
under the National Environmental Policy
Act (NEPA) (42 USC 4321 et. seq.~) due
to the cumulative impacts of the Federal
actions (maintenance dredging, navigation
improvement dredging, and permitting of
the associated berthing areas) and the
significant public concern over disposal of
the dredged material. The content of the
EIR/S was prescribed in the June 1991
MEPA certificate and June 1992 NEPA
scoping documentation which appear in
Appendix A of the Draft EIR/S published
in April 1994.
After publication of the Draft EIR/S in
April 1994, the public review process of
the DEIR/S included several public
meetings, meetings with concerned interest
groups, and the receipt of the sixty-one
comment letters from federal, state, and
local agencies, commercial interests,
private interest groups and private citizens.
Public meetings were held in Boston and
Hyannis on May 17 and 19, 1994
respectively. These meetings were
planned under the direction and guidance
of the New England Division (NED)
Corps and consisted of a variety of
techniques tailored to the individual project
including a public partnership between the
NED-Corps, Massport and public
advocacy groups such as the Conservation
Law Foundation and Save the Harbor/Save
the Bay.
The meetings were designed to offer
multiple opportunities for public input in
identifying issues early in the process so
they could be fully addressed through
additional data collection and analysis and
publication in the FEIR/S. Afternoon and
evening sessions were held at both
locations to allow for maximum
opportunity for interested public comment.
The Boston sessions resulted in formal
comments from sixteen individuals and
public interest groups. The Hyannis
meetings generated formal comments from
seven individuals and groups. Transcripts
of both meetings are provided in Appendix
B. On July 28, 1994, a special meeting
was held in Nahant in response to a
request from the Board of Selectmen.
Thirty one speakers offered comments for
the record. A copy of the transcript from
this meeting is also included in Appendix
B.
At the request of specific individuals and
groups, presentations were made at various
locations with stakeholders and groups,
and one-on-one presentations and
interviews.
These meetings were in addition to the
public participation process described in
Section 1.4 of the DEIR/S.
1-9
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1.2.3 Public Participation Process
The Corps and Massport recognize that
large projects which may impact the public
cannot be accomplished unilaterally.
Rather, the success of the project depends
on involving key groups effectively. This
general principle had a number of
important implications. Key parties
needed to be identified which either had a
stake in the outcome (regulatory agencies,
environmental groups, and harbor users),
or could provide useful information to the
Corps, Massport, and its consultants.
Effective involvement of these parties
required that they be consulted early, that
they be provided timely information on the
progress of the project, and they have the
opportunity to present diverse points of
view. To that end, the Corps, Massport
and its consultant developed a public
participation process which consisted of a
broad-based Advisory Committee
supplemented by targeted, focused working
groups to assist project planners in
particular technical areas such as sediment
characterization and disposal alternatives.
A list of Advisory Committee and
Working Group members is provided in
Appendix C.
The Advisory Committee convened twice
during the preparation of the FEIR/S, in
September 1994 and March 1995. The
Advisory Committee was instrumental in
assisting the project team in identifying
major areas of concern regarding the
DEIR/S that required additional data
collection or analysis in the FEIR/S. The
meetings also identified the need for two
supplemental working groups. These
consisted of a working group meeting in
November 1994 focusing on developing a
comprehensive data base of dredged
material treatment and disposal
technologies. The results of the
technology screening process are described
in Chapter 3.0 of this FEIR/S. A second
working group convened in December
1994, focusing on mitigation and
monitoring
concerns that would be developed into a
comprehensive Dredge Management Plan,
as required by the Secretary's MEPA
certificate (see Appendix A).
1.2.4 Inter-Agencv Coordination
In addition to the public participation
process, the project team also engaged in
several meetings with combined EOEA
agencies since the late summer of 1994.
These meetings assisted the project team hi
clarifying technical comments the agencies
provided in letters responding to the
DEIR/S; assisting the project team in
designing data collection studies;
coordinating EOEA agency
responsibilities; and focusing on related
pre-permitting activities. These meetings
have been invaluable to the development of
this FEIR/S.
Meetings were also held between the
Federal cooperating agencies and the
NED-Corps to address Federal issues
concerning comments on the Draft EIR/S
and the permitting process under the Clean
Water Act and the Marine Protection,
Research, and Sanctuaries Act. Formal
meetings were held with the Federal
agencies in November 1994 and March
1995, as well as informal meetings, to
narrow the list of practicable disposal sites
based on functions and values, under a
process known as the Federal Highway
Methodology, as well as cost and
engineering feasibility.
The extensive comment and input process
described above has assisted the project
1-10
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team in identifying and assessing project
alternatives and their impacts. Volume 2
of this FEIR/S contains detailed comment
responses for each letter received or
comment made at the public meetings.
The next section highlights the most
significant changes made to the project in
response to the public and agency review
process. Each of these issues, and many
others, are fully developed hi the later
pages of this document.
1.3 SUMMARY OF MAJOR
CHANGES FROM THE DEIR/S
This section highlights significant findings
and issues that were raised as concerns
during the DEIR/S review process and
how they have been resolved in the
FEIR/S.
1.3.1 Use of Massachusetts Bay Disposal
Site fMBDSI
A great deal of public comment on the
DEIR/S centered on the use of the MBDS
as a potential disposal site for
contaminated sediments. The comments
can be grouped into three major areas as
follows:
• The expressed concern that the site
is not suitable for the disposal of
contaminated materials until
capping is proven effective in
eliminating transfer or
bioaccumulation of contaminants
into the environment in a
demonstration project as required
by 40 CFR 228.12, as amended.
• A perception that the Corps has
not demonstrated that they can
successfully cap at MBDS depths,
based on the current body of
engineering studies available from
the Corps.
• The expressed concern that
contaminated material loss during
the drop of dredged silts into deep
water may be more significant than
that projected in the DEIR/S, with
resulting potential deleterious
effects on aquatic life near the site
and at Stellwagen Bank.
In response to these concerns, the
project proponent and the Corps have
eliminated the MBDS as a viable
disposal option for contaminated silt for
the BHNIP project. The MBDS will be
used for disposal of uncontaminated parent
material and is being considered for
disposal of future maintenance dredging
material provided the Corps or other
agencies effectively complete
demonstration projects for capping or other
technology as described in Section 2.4 of
this document.
1.3.2 Use of Cost as a Ranking Factor in
Evaluating Disposal Alternatives
In screening and ranking the desirability of
various disposal options, the DEIR/S used
disposal of contaminated silts at MBDS as
a baseline cost against which other disposal
options were measured. Since MBDS is
not a viable option for the disposal of
contaminated silts, for this phase of the
project, this cost baseline no longer holds
for disposal of that material. While costs
are still used as a ranking factor in this
FEIR/S it is no longer the primary
consideration, nor are options rejected
solely on this basis. We have eliminated
(in response to comments) any across-
the-board cost cap in screening sites and
1-11
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disposal options. This has been
substituted with a two-step approach that:
1) evaluates sites and options in terms of
environmental acceptability; and 2) ranks
the most environmentally acceptable
alternatives based on cost-effectiveness.
Under this approach, no environmentally
acceptable option is discarded without
receiving a review on its merits.
1.3.3 Emphasis on Using Previously
Impacted Areas
Many comments from the public made
clear that they preferred confining the
impacts of dredged silt disposal to already-
impacted areas in the Inner Harbor, rather
than realizing impacts in the relatively
pristine Outer Harbor or Massachusetts
Bay. The concerns centered on the
following issues:
• Fisheries habitat disruption,
especially prune valuable lobster
habitat at the Meisburger sites.
• Overlap of the MWRA outfall
impacts with use of Meisburger 2
could make tracing contamination
sources difficult.
• Boston Harbor sediments should
not be "exported" to Massachusetts
Bay, but kept confined on land or
in the Inner Harbor.
• The increasing pressure on the
fishing industry as a result of
dwindling stocks will be
exacerbated by the use of the open
water aquatic sites.
To address these concerns, the project
proponent and the Corps undertook a
detailed fish, lobster and benthic survey of
all potential aquatic sites to evaluate and
compare their relative resource value. The
sampling program and results are fully
described in Chapter Four. Based on this
analysis, and in part on public concerns,
the project proponent and the Corps
have eliminated the use of sites in the
Outer Harbor and Massachusetts Bay
from further consideration for the
disposal of the BHNBP silt. Future
studies, including capping and geotextile
technology review, will be undertaken to
evaluate the potential use of these sites for
future maintenance material.
1.3.4 Sediment Characterization
The DEIR/S indicated that the Corps
determined that approximately 360,000
cubic yards (cy) of silt was suitable for
ocean disposal based on bulk chemistry,
bioassay and bioaccumulation data required
by ocean dumping regulations in 40 CFR
Chapter 1, Subpart B. However, using the
same data, the U.S. Environmental
Protection Agency (EPA) determined that
none of the silt was suitable for unconfined
ocean disposal. In response to these
comments, the Corps adopted the more
conservative position and assumed that all
silt from the Corps improvement and
beneficiary dredging, and the Massport
berth dredging, is considered unsuitable
for unconfined ocean disposal.
Therefore, disposal options were
developed for the entire in-situ silt volume
of 1.1 million cy. Parent material,
consisting of uncontaminated clay and
sand, from the deepening and improvement
of the Federal channels, was determined to
be suitable for disposal at the MBDS.
Potential options for the beneficial re-use
of the clay material are discussed in
Chapter 3. Rock to be removed from the
channels will be used to armor disposal
sites from ship and storm-generated waves
1-12
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or other beneficial uses. Rock remaining
after these applications will be disposed at
the MBDS.
geotextile containers, as they may become
available and suitable for future
maintenance dredging purposes.
1.3.5 Treatment Technologies
The public review process generated great
interest hi identifying and considering new
technologies for handling and treating
contaminated marine silts. A number of
commentors suggested that the project
proponent and the Corps look more
carefully at these technologies. The
technology that generated the most interest
was the potential use of geotextile
containers. As described in Section 2.4,
the Corps is monitoring on-going projects
in other Corps districts around the country,
and at the Corps' Waterway Experiment
Station (experimenting with geotextile
containers). This technology is a
containment technology rather than a
chemical or biological treatment of
sediments per se. The project proponent
and the Corps also polled thirty-seven
technology providers using a detailed
questionnaire developed with the assistance
of the Disposal Options Working Group.
The technologies screened through the
questionnaire process are considered not
currently practicable due to a lack of
demonstrable success, logistics of
deployment, "permittability" questions,
cost, management of by-products, and
the ability of the technologies to handle
the volumes and types of contaminated
silts generated by the Project. The
technology survey is more fully described
in succeeding sections of this FEIR/S.
The survey form and results are presented
hi Appendix D. The Corps will continue
to work with other Corps districts to
monitor the development of treatment and
containment technologies, especially
1.3.6 Site Screening and Development of
Disposal Options
As described in the DEIR/S, the site
screening process was developed hi
coordination with the Advisory Group and
a specific Disposal Options Working
Group. Several commentors raised
concerns as to how the screening criteria
were applied, especially concerning
minimum site capacity requirements and
the use of a baseline cost comparison. As
stated in Section 1.3.3, cost information
continues to be one factor hi the
practicability determination, but will no
longer be used as the primary screening
criterion. In addition, limited site capacity
is not viewed as a fatal flaw hi site
selection, but is considered with other
factors such as environmental impacts
associated with a site, developability of the
site, constructability and access concerns,
permittability, neighborhood impacts, and
costs of development for unit of storage.
Individual sites .were not screened out
based solely on their limited capacity or
higher total cost if, in combination with
other sites, they might comprise least
environmentally damaging practicable
alternatives (LEDPA). Cost, capacity and
other practicability considerations were
applied only after the environmental
analyses were completed.
1.3.7 Detailed Dredge Management Plan
Several commentors requested more
specific information on dredging and
disposal performance standards to ensure
compliance with permit conditions and
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compliance with permit conditions and
general environmental quality standards.
As an example, the project team has
responded to these concerns by specifying
the use of an environmental bucket to
minimise release of contaminated sediment
during dredging and outfitting the bucket
with a sensor to detect whether it is in a
closed condition or if closing is impeded
by debris.
The Dredge Management Plan (DMP) also
contains:
• specific recommendations for
dredging equipment;
• detailed descriptions of the
dredging and material disposal
operations;
• the scheduling and timing of
dredging and disposal operations;
• an overview of potential
environmental impacts caused by
dredging and disposal and
proposed techniques for mitigating
these impacts;
• environmentally-based dredging
performance standards;
• a description of recommended
monitoring plans during dredging
and for long-term, post-
construction monitoring;
• a discussion of operational
contingency plans that would be
implemented to assure the safe and
successful completion of the
project.
1.318 Summary of Changes
The issues addressed in the preceding
paragraphs have resulted in the following
project changes:
• Based on applicable environmental
screening criteria, all silts
generated by the project are
considered unsuitable for
unconfined ocean disposal.
• The MBDS, Subaqueous B and E,
Meisburger 2 and 7, Boston Light
Ship, and Spectacle Island CAD
have been eliminated from further
consideration as practicable
disposal sites for BHNIP silt.
These sites are still being
considered as potential disposal
locations for future maintenance
dredging. Use of these disposal
sites for future maintenance
dredging may require additional
studies, demonstration projects, or
the application of appropriate
technologies that may render these
sites practicable in the future.
• All parent material, consisting of
sand and clay, generated by the
project is considered suitable for
disposal at MBDS or for beneficial
re-use, including as a potential
source of capping material for
unlined municipal landfills.
• Technologies will continue to be
assessed by the Corps for their
potential applicability to future
maintenance dredged material.
• Cost considerations and capacity
are no longer considered to be fatal
flaws in disposal site screening.
Cost is factored in only to assess
1-14
-------
the relative cost-effectiveness of
disposal scenarios determined to be
environmentally suitable and to
determine practicability. Capacity
is only one factor considered in
site screening and combinations of
sites of limited capacity may
constitute acceptable disposal
scenarios.
1.4 FORMAT OF THE FEIR/S
The foregoing sections highlight significant
issues arising from the careful
consideration this project has received by
Federal, state and local agencies;
commercial interests; public interest
groups; and private citizens. The project
proponent and the Corps are grateful for
the tune and effort expended by so many
hi assisting in the development of an
environmentally acceptable and fiscally
responsible project. A list of preparers is
provided in Table 1-5. The remainder of
this section describes the format of this
document to assist the reader in locating
critical text.
Due to the complexity, of the project, and
the extent of the public review process,
this FEIR/S is designed to serve, as much
as possible, as a stand-alone document.
This FEIR/S incorporates by reference in
its entirety the Draft EIR/S and all
referenced technical reports and studies.
Specific references will be made to
portions of the DEIR/S as appropriate to
avoid duplication of massive technical
appendices. Critical issues developed in
the DEIR/S will be extracted and distilled
in the FEIR/S so that the general reader
will understand the issues presented.
As a result of our effort to make this
FEIR/S readable, and as a result of
numerous comment letters, this FEIR/S
consists of three volumes. Volume 1
contains the main text material; Volume 2
consists of a photocopy of comment letters
received since the publication of the
DEIR/S and an individual response to each
letter. Volume 3 contains all referenced
appendices.
A summary of the contents of Volume 1
are as follows:
• Chapter Two (Project Description)
presents the dredging project, its
limits and components, and the
alternatives considered in designing
the channel and berth dredging.
This section provides the final
calculations of parent material to
be dredged for the maintenance
and improvement projects as well
as material excavated for the
preferred disposal options. It also
describes future maintenance
dredging requirements after project
completion over the 50-year design
life of the project.
• Chapter Three (Material Disposal
Site Selection Process) presents the
dredged material disposal option
selection process. Of special note
is the discussion of additional data
collection efforts conducted hi
response to comments received
during the public review process.
These efforts included a fishery,
benthic and lobster study and short
and long-term modeling to
determine water quality impacts.
• Chapter Four (Selection of
Preferred Disposal Option) is the
heart of the environmental analysis
portion of this FEIR/S. It presents
a detailed explanation of the
1-15
-------
environmental benefits and
detriments of a number of disposal
scenarios. The discussion is
developed against the framework
of Massachusetts Wetlands
Protection Act and water quality
standards, federal functions and
values assessments under the Clean
Water Act, and a comparison of all
least environmentally damaging
alternatives. Finally, practicability
concerns are layered onto the
evaluation to consider cost,
availability, and logistics to
eventually arrive at a single
preferred disposal scenario.
Chapter Four culminates with a
detailed description and evaluation
of the preferred disposal option.
The preferred option consists of in-
channel disposal, with capping.
Chapter Five (Dredge Management
Plan) is the technical core of this
document. It presents the detailed
Dredge Management Plan (DMP)
that was prepared in outline form
intheDEIR/S. The DMP
provides a detailed sequence of
construction for both the dredging
and disposal operations. The plan
also addresses concerns raised in
the comment letters regarding
construction and post-construction
monitoring and contingency
planning for reasonable and
foreseeable environmental or
operational occurrences.
Mitigation concepts, both resource
and operationally-oriented, are
described in Chapter Six
(Mitigation Planning and
Proposals). Mitigation concepts
are presented in sufficient detail to
enable the reader to understand the
range of mitigation considered by
the project proponent and the
Corps as well as the issues which
are likely to be addressed during
the permitting process.
The permitting and regulatory
requirements which the project
must meet are defined and
described in Chapter Seven
(Regulatory Compliance).
Chapter Eight (Section 61 Finding)
provides a draft Section 61 finding
to meet Massport and EOEA
agency obligations under 301 CMR
11.00.
Chapter Nine (Literature Cited)
provides detailed references for the
technical reports cited in the text.
Chapter Ten (Glossary of Terms)
provides definitions for the
technical terms used in this report.
1-16
-------
CHELSEA
*
Chelsea St
Bridge
\~V EAST BOSTON
CHARLESTOWN
*Mr \ 5">> v'"•
*?•£>?* ?* "' ^-'./•SumwrandCallahan Tunnels
f^r:^^Xx<%
I *\ ;,§«^V y<-'J v^ ",-
v ~. "~«^ x.-^y 5* - - ^ - s^*xThmt Harbor Tunnel (under consfr.) ^.,
DOWNTOWN
BOSTON
Fajancal®,^'"* V^5."'%1 /*v"* *S-'*S C^ ' " V' "^'^'^x" "' "
oismc. ^JL^ ''"IB'JH-40 '"'^^ ^ ^i;^/«'^X
^p* **a'i> :r
_, ^ ••—™
ScateinFeet
=S^=Si
0 2000* 4000*
; Massport Properties
Non-Massport Properties
1. Fort Independence
2. Conley Terminal
3. Coastal Oil South
Boston
4. MBTA Power Plant
5. Boston Edison Power
Plant
6. The Black Falcon
Cruise Terminal
7. The Harbor Gateway
8. Coastal Cement Term.
9.Boston Marine
Industrial Park, South
Jetty, DrydockS
10. Massport Marine
Terminal, North Jetty
11. General Ship Corp.
12. Boston Fish Pier
13. World Trade Center
14. Federal Courthouse
site
15. Museum Wharf
16. Boston Tea Party
Ship Museum
17. Rowes Wharf/Boston
Harbor Hotel
18. India Wharf
19. Central Wharf
20. Long Wharf/Marriott
21. Commercial Wharf
22. Lewis Wharf
23. Lincoln Wharf
24. Battery (Constitution)
Wharf
25. US Coast Guard
Support Center
26. Paul Revere Park
27. Constitution Plaza
and Constitution Marina
28. USS Constitution and
National Park
29. Chariestown Navy
Yard
30. Mystic Pier t1
31. Mystic Pier 48 Salt
Terminal
32. US Gypsum
33. Moran Container
Term.
34. Blue Circle Atlantic
35. Medford Street Term.
36. Chariestown Marine
Park
37. Boston Edison
38. Prolerized Scrap
Terminal
39. Distrigas Liquified
Natural Gas Terminal
40. Exxon Oil Term.
41. Independent Cement
Corporation
42. Coldwater Seafood
Terminal
43.AdmiraTsHill
Condominium/Marina
44. Atlantic Fuel Terminal
45. Eastern Minerals Salt
Terminal
46. Coastal Oil New
England, Inc.
47. Walton Pier
48. Gulf Oil Terminal
49. Coastal Oil Terminal
50. Northeast Petroleum
Terminal
51. BP Oil Term.
52. Global Petroleum
Terminal
53. Mobil Oil Terminal
54. Boston Towing &
Transportation Company,
Inc^North Terminal
55. General Ship and
Engine Works
56. East Boston Piers
57. Boston Marine Works
58. Logan International
Airport
59. Logan Office Center
Figure 1-1
-------
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CHELSEA
Inner Confluence
Channel
CHARLESTOW
iumner and CaUahan Tunnels
Logan
Airport
-Third Haibor Tunnel (under const)
~-~».^
Deepen
Mystic River to 40'
Inner Confluence to 40'
Reserved Channel to 40'
Chelsea River to 38'
SOUTH BOSTON
Boston Harbor Dredging Project EBR/S
F i g u r e 1 - 3 Boston Hgrbor
Navigation Improvement Project
General Plan
Scale:
Source:
0 2000' 4000'
Scale in Feet
New England Division, Corps of Engineers
-------
",5 *_••< ..$,..., -..,•• % f r y ,; - (&&/''•. '*
-, /r.-^ ,>t- s ^-^ - , " - »' ' - -V . ,
- - •---^.¥;-?^X^^^-"^/.^:^^^
- ' ...:'^^;^vS^^^-'•^^;^/••-:^
Boston Harbor Dredging Project EIR/S
Scale:
0 2000' 4000'
Scale in Feet
Figure 1-4 Boston Harbor
Navigation Improvement Project
General Plan
Source:
New England Division, Corps of Engineers
-------
^-^r>i -: * ~>:^^
/v '^:^r;^ri^"
,^>^Y^/V^#^
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's - -.-/r s://?
*.°: '/ - -v ^
Boston Harbor Dredging Project EIS/R
Figure!-5
Navigation Improvement Project
Reserved Channel
Scale:
Source:
Scale in Yards
Boston Inner Harbor Navigation Chart
-------
Boston Harbor Dredging Project EIR/S
SOU
Figure1-6
Navigation Improvement Project
Mystic River
Source:
Boston Inner Harbor Navigation Chart
-------
Boston Harbor Dredging Project EIR/S
Scale:
Scale in Yards
g u r e
1-7
Navigation Improvement Project
Chelsea Creek
Downstream of Chelsea St. Bridge
Source:
Boston Inner Harbor Navigation Chart
•7-£3
-------
Northeast Petroleum
Coastal Oil
Gibbs
Global
CHELSEA
EAST BOSTON
See Sheet a
of this figure for
deta3s downstream of
Chelsea St Bridge
Existing Channel Limits
Dredge to-38 MLW
Intertidal
Project Beneficiary
helsea St.
Bridge
Boston Harbor Dredging Project EIR/S
Figure Navigation Improvement Project
1 _ 8 Chelsea Creek
Upstream of Chelsea St. Bridge
Source:
Boston Inner Harbor Navigation Chart
-------
y PROLERIZED
•* '
| REVERE SUGAR | I MORAN I U^ Mystic
' V ' I MUttAN I ^g> Channel
[MYSTIC PIERS
CHARLESTOWN
Z.j^sr&bis&'X'.
Longfellow
* ' ' /.• ' / Bndge
t,*r4/ -I BOSTON
J ARMY BASE ^t>t -^'V^' -
BOSTON EDISON
INTAKE
Proposed Dredging - (Non-Federal)
Terminal/Berth Areas
BOSTON EDISON
BARGE BERTH
Boston Harbor Dredging Project EIR/S
Figure 1-9
Location of Federal Channel
and berth area dredging
Scale:
Source:
Scale in Yards
Boston Inner Harbor Navigation Chart
1-25
-------
TABLE 1-1.
TERMINALS AND DOCKING FACILITIES
Conley Terminal
Coastal Oil*
Black Falcon Cruise Terminal
South Boston Army Base
Coastal Cement
Boston Marine Industrial Park
Massport Marine Terminal
General Ship
Boston Fish Pier
World Trade Center
McKie lighter
Rowes Wharf
Central Wharf
Long Wharf
U.S. Coast Guard Support Center
Charlestown Navy Yard
Mystic Pier 1
Mystic Pier 48
U.S. Gypsum
Moran Container Terminal
Blue Circle Atlantic Cement, Inc.
Massport-Medford Street Terminal
Boston Edison*
Distrigas LNG Terminal*
Exxon Oil Terminal*
Independent Cement Corp.
Coldwater Seafood Terminal
Atlantic Fuel Terminal
Eastern Minerals Salt Terminal*
Coastal Oil New England, Inc.*
Walton Pier
Gulf Oil*
Coastal Oil Revere*
Northeast Petroleum Terminal*
BP Oil Terminal
Global Petroleum
Mobil Oil Terminal
Boston Towing and Transportation Co., Inc.
General Ship and Engine Works
East Boston Piers
Boston Marine Works
Logan Airport Water Shuttle
Deer Island-MWRA
Lewis Street-East Boston
Prolerized Scrap Metal*
* Berths receiving dkect economic benefits from BHNIP
-------
TABLE 1-2.
VESSEL ACTIVITY IN THE PORT OF BOSTON:
ARRIVALS WITH DRAFTS GREATER THAN 18 FEET*
Year
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
Dry Bulk
Carriers
225
235
132
129 '
120
126
134
118
118
106
92
77
82
81
89
72
59
39
41
39
52
General
Cargo
480
401
196
140
160
137
141
117
134
119
107
91
85
89
81
74
89
75
88
78
77
Fully
Containerized
General
Cargo
163
244
276
272
279
262
265
284
289
291
277
200
215
248
237
202
210
168
154
173
198
Passenger
36
53
24
19
9
8
8
14
25
28
21
14
19
23
18
13
15
39
33
20
48
Tankers/
LNG
635
665
633
571
583
628
542
548
440
427
337
323
374
315
308
300
318
296
294
280
308
TOTAL
1539
1598
1261
1139
1151
1161
1140
1081
1006
971
834
705
775
756
733
661
691
617
610
590
683
* As handled by Boston Pilots.
Source: Massport and Boston Shipping Association
-------
TABLE 1-3.
TRIPS AND DRAFTS OF VESSELS USING BOSTON HARBOR
1960-1993
Number of Trips
Year
1960
1965
1970
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1990
1991
1992
1993
Draft
41-45 ft.
—
3
1
3
—
—
—
—
—
—
—
—
—
—
—
—
—
1
1
1
1
Draft Draft
36-40 ft. 3 1-35 ft.
24 438
53 440
214 477
195 368
218 396
226 427
206 371
219 370
127 311
122 314
76 292
77 264
131 210
113 209
133 170'
122 199
154 156
174 291
133 304
131 326
144 405
Draft
25-30 ft.
669
500
483
598
649
667
590
675
638
705
677
539
455
453
123
285
308
387
371
352
295
Draft
20-25 ft.
2,135
2,074
1,622
1,051
1,028
826
704
743
667
669
711
710
852
848
398
351
270
689
566
576
627
Total Trips for Year
3,266
3,067
2,799
2,213
2,294
2,146
1,871
2,007
1,743
1,810
1,756
1,590
1,648
1,623
824
957
988
1,542
1,375
1,386
1,472
This tables was initially prepared as part of the Boston Harbor Marine Traffic Report by the Maguire Group, April 1988, for the
Massachusetts Water Resources Authority and included data for 1960-1985. The 1986-1988 information was obtained from the U.S.
Army Corps of Engineers.
Source of 1960-1988 numbers:
Source of 1990-1993 numbers:
Waterbome Commerce Statistics, U.S
Impact Analysis Division, U.S. Army
. Army Corps of Engineers
Corps of Engineers
fjlf
-------
THB PORT OF BOSTON
CARGO VOL«E AND IMPACT ON ECONOMIC
Beneft to the Port of Conservative 3*. Annual Rate of Growth
Economic Impact Assuming
Annual Decline in Cargo Volume
Percent Decline in $1,000 Benefit
Each cargo ton adds over $1,100 in value
^
^^
-------
TABLE 1-5. LIST OF PREPARERS
PERSONNEL
•———«—•
IMASSPORT
L_ —
|Ms.JaneenHansen
j
Dr.NonnFaramelli
I US. ARMY CORPS OF
ENGINEERS
Mr. Peter Jackson
Ms. Catherine Demos
Mr. Robert Meader
TITLE
Director and Project Manager
Director, Transportation &
Enkonmental Planning
Project Manager
I Marine Ecologist
Engineering Manager
QUALIFICATIONS
MA. in City and Regional Planning from
Harvard University. Fourteen years experience
transportation analysis and policy planning.
in
B S in Chemical Engineering from BuckneU
University and Ph-D. from Temple University
10 years consulting experience and 16 years at
Martin transportation and environmental
planning.
MS. in Civil Engineering from Stanford
University. 25 years experience with the Corps
oSgSLs inSan Francisco District and New
EnglaSDivision in engineering and managrng
water resources projects.
M S in Coastal Zone Management/Biology
fromUniversityofWestFlorida. Sevenyears
S.eriencewiththeCorps. **%*•£**
environmental assessments andEIS s for
coastal and marine projects.
B S C E from Worcester Polytechnic Institute,
MC.RP- from Rutgers. Over 18 years
experience with the Corps of Engineers in the
study and management of inland and coastal
navigation projects.
If
I-
-------
TABLE 1-5 (CONTINUED). LIST OF PREPARERS
Dr. Thomas Fredette
Marine Scientist
PhD. in Marine Science from the Virginia
Institute of Marine Science at The College of
William and Mary. 10 years of experience in the
area of environmental impact research,
assessmentand monitoring. Program Manager
of New England Division's Disposal Area
Monitoring System (DAMOS).
NORMANDEAU
ASSOCIATES
Ms. Virginia Treworgy
Managing Corporate Officer
and Principal Author
MA. in Government and Public Policy from
Harvard University and is an attorney admitted
to practice in Massachusetts. 17 years
experience in environmental impact assessment,
permitting, and management of Remedial
Investigation and Feasibility Studies at state and
federal hazardous waste sites.
Ms. Ann Pembroke
Marine Ecologist
MS. in Marine Biology from University of
Delaware. 13 years experience with the firm.
Project manager and senior report author for
numerous assessment projects dealing with
manna issues.
Ms. Sarah Allen
Wetland & Wildlife Ecologist
M.S. in Wetland Ecology from University of
Rhode Island. Over 11 years in natural resource
research and consulting. Specializes in wetland
delineation and jurisdictional assessments, and
botanical and wildlife surveys.
Ms. Mary Small
Wildlife Biologist
MS. in Wildlife Management from Universily of
Maine with emphasis in bird and small mammal
ecology. 9 years experience life sciences.
Mr. James Bajek
Dredged Material Specialist
B.A. hi Biology from University of North
Florida. 17 years experience in the planning,
material evaluation, and permitting of dredging
projects.
31
-------
TABLE 1-5 (CONTINUED). LIST OF PREPARERS
Mr. Paul Geoghegan
OCEAN & COASTAL
CONSULTING (OCC)
APPLIED SCIENCE
ASSOCIATES (ASA)
BOELTER & ASSOCIATES
Ms. Alice Boelter
WADE RESEARCH, INC.
Dr. Michael J. Wade
DIAMOND
ENVIRONMENTAL
ASSOCIATES
Ms. Harriet Diamond
Fisheries Biologist
Marine Engineering, dredging
specialists
Fate and Transport Modeling
Principal Port Planner
Principal Scientist, Marine
Organic Gee-chemist
Regulatory Specialist
M.S. in Wildlife and Fisheries Sciences from
Texas A&M University. American Fisheries
Society certified fisheries scientist experienced
in environmental assessment and population
dynamics offish communities.
Provided specialized services in dredge
management planning and interpreting ship
simulation data for disposal cell design.
Provided specialized services in fate and
transport water quality modeling for aquatic
disposal facilities.
Master in Public Policy studies from the
University of Michigan- Over 20 years
experience in urban planning and project
permitting.
Ph.D. in Marine Geochemistry from University
of Rhode Island. Dr. Wade provides chemical
oceanographic consulting services to
government and industrial clients. He is an
organic geochemist with over 20 years
technical and management experience in a
variety of research programs, with special
emphasis on pollutant fluxes in the
environment.
Masters in Biological Oceanography from the
University of Rhode Island 15 years
experience in environmental consulting,
permitting and planning.
-------
TABLE 1-5 (CONTINUED). LIST OF PREPARERS
WARNER & STACKPOLE
Mr. Michael Leon
LINOWES & BLOCHER
Mr. Kenneth Kamlet
Legal Counsel
Legal Counsel
Masters in City and Regional Planning.
Partner with the law firm Warner &
Stackpole and head of the firm's
Environmental Law Group. Admitted to
practice in Massachusetts.
Masters in Biochemical Sciences.
Environmental counsel in securing necessary
wetlands and other environmental regulatory
approvals.
y-33
-------
-------
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Chapter Two: Project Description
This chapter describes the elements of the
final preferred option for the design of the
BHNIP. This chapter also considers issues
in response to comments received on the
DETR/S regarding project design
alternatives that minimize or eliminate the
need for the project This Chapter begins
with a description and comparison of the
various alternative dredging plans that were
considered in the Corps' economic impact
analysis which formed the basis for
Congressional approval of the project
This chapter concludes with the
maintenance dredging plans for the 50-year
life of the project and a description of
potential future demonstration projects to
be undertaken prior to maintenance
dredging of the completed BHNIP.
2.1 PROJECT DESIGN
ALTERNATIVES
The project design alternatives evaluated
for the BHNIP include:
• no action,
• maintenance dredging only
without improvements,
• full project to the proposed
depths,
• expanded project,
• reduced project, and
• delayed project
Both (he MEPA certificate and NEPA
guidance require that the EEER/S provide a
discussion of the consequences of not
carrying out the project, often referred to
as the "No Action" alternative. The
BHNIP has been evaluated in terms of two
scenarios under the "No Action" alterna-
tive. The first considers no improvement
and no maintenance dredging. The second
considers no improvement dredging, but
with maintenance dredging to maintain
currently established channel dimensions.
2.1.1 No Action. No Maintenance
Dredging
This alternative assumes that no dredging
activity, including maintenance dredging,
would take place. Silty material is
continually deposited in the navigation
channels and berthing areas by rivers and
tidal action. Organic, material is deposited
from combined sewer outfalls (CSO's) and
the outfall pipe at Deer Island. Sediment
deposited in the channels and berthing
areas, since they were last dredged, will be
referred to as "silt" in this report, to
differentiate it from underlying ("parent")
material (blue clay, gravel, etc.) and rock
proposed to be dredged in the BHNIP.
The authorized channel depths in Boston
Harbor were last maintained in 1983 when
dredged material was disposed at the
Massachusetts Bay Disposal Site. On
average, the Reserved Channel and turning
areas, Mystic River and the Inner
Confluence, and Chelsea Creek have a silt-
ation rate of less than 0.2 inches, 0.2
inches and 0.8 inches per year,
respectively. This average rate, however,
does not account for specific areas that
shoal much faster and which require
dredging more frequently. Areas within
2-1
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the tributaries that tend to shoal at
substantially higher rates than the averages
cited eventually control navigation through
the tributaries. Not'maintaining the
channels to the currently authorized depths
is increasingly making the port unable to
accommodate the present shipping fleet of
deep draft container ships and petroleum
tankers. Currently these vessels draw at
least 36 feet to 37 feet if loaded for a
minimally economical operation. Some
transits, particularly in the Chelsea Creek,
must be made in daylight hours. There are
limited opportunities for such transits at
high tide, especially during the winter
months. Limited tidal operations are not
consistent with efficient shipping, cargo
handling or scheduling. Ultimately, more
material would have to be shipped into
Boston via barges, necessitating more trips,
higher transportation costs, and greater
exposure to risks of accidental spills (see
Section 1.1).
Leaving the top layer of silt material in
place continues to expose marine
organism.^ that live in or use the area, to
contaminants. This material is also subject
to continual resuspension in the water
column during vessel transits in shallower
areas. Removing and confining the
material reduces this risk of exposure. The
environmental or economic benefits
accrued by leaving the material in place are
few. MWRA (1993) has reported that with
die reduction of toxics and solids in their
discharge, cleaner sediments will settle
over the older, more contaminated
sediment. Non-point source pollution, such
as urban runoff, also contributes to the
contaminant load. However, several years
would be needed to cover the existing
sediments with the cleaner material.
Therefore benefits are provided by
dredging the silt before new deposition
occurs.
The no action/no maintenance dredging
alternative also considered relocating
appropriate port facilities to the -40 foot
Main Ship Channel waterfront This would
eliminate the need to deepen the tributary
channels. The 1988 Boston Harbor
Navigation Improvement Project Feasibility
Report prepared by the Corps of Engineers
investigated the construction of pipelines
and Inner Harbor offloading facilities.
This alternative 'was found not to be
feasible for several reasons. These
included the minimal amount of available
areas for offloading facilities, cost, and the
kck of interest from terminal owners to
move their facilities. Relocation of active
port terminals to these sites is not readily
achievable because of land assembly
issues, and because of the rigorous
regulatory process that such relocation
would trigger. The acquisition costs
notwithstanding, the roadway connections,
rezoning, potential litigation, and the
infrastructure required to establish the port
terminals closer to the main ship channel
would entail years of effort. The Port of
Boston cannot wait for this to happen. The
BHNIP needs to occur now.
Although the Main Ship Channel would
not need to be deepened, navigational
access from the Main Ship Channel to the
terminals would likely be required. The
terminals would be re-located along the
west side in Boston along Northern
Avenue and the east side of the Harbor in
East Boston adjacent to the -40 foot Main
Ship Channel. Much of this area is
currently occupied with businesses.
Additional dredging would be required
from the Main Ship Channel to make these
berth areas accessible-.
In summary, the relocation of the
infrastructure of a major port such as
Boston Harbor would require an enormous
2-2
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amount of funding, relocation of terminals,
availability of real estate and construction
of fuel pipelines without eliminating
dredging. Costs for this type of non-
structural alternative would not be shared
by the Federal government Infrastructure
rebuilding would be the responsibility of
the individual terminal owners and
appropriate State and local governments.
2.1.2 No Action, with Maintenance
Dredging
The no action, with maintenance dredging
(to -35 feet MLW) alternative, would allow
the Boston Harbor Federal Channels and
the project berths to remain in their
existing configurations. Table 2-1 lists
dates of the last dredging in each tributary
(not including berths) as well as projections
of annual and project life (50 yrs.)
accumulation. The no action, with
maintenance dredging alternative would be
analogous to maintaining the currently
authorized depths. This consists of three
main entrance channels, -27, -30 and -
35/40 feet MLW converging at the Outer
Confluence in President Roads. A -40 foot
MLW anchorage is located adjacent to the
channel at President Roads. From
President Roads to East Boston the Main
Ship Channel has two 600 foot lanes. The
inbound lane is -35 feet MLW and the
outbound lane is -40 feet MLW. The 40
foot depth continues upstream at an
average width of 700 feet to the -35 feet
MLW Inner Confluence Area at the
mouths of the Mystic River and Chelsea
Creek Three active deep draft tributary
channels, the Reserved Channel, Mystic
River and Chelsea Creek are provided with
35 foot depths.
This alternative however, precludes the
regional economic benefits of the
authorized improvement project described
in Section 1.1. Environmental impacts
associated with the maintenance alternative
include temporary disturbance from
dredging and disposal activities, which is
comparable to the improvement project
Maintenance dredging would remove
primarily silty materials that have been
transported into the channels since they
were last dredged (Table 2-1). Dredging
impacts include temporary and localized
water quality degradation from turbidity
and release of contaminants into the water
column.
Disposal impacts would be dependent on
the site selected. Water-based sites would
have a temporary increase in turbidity and
release of contaminants. Alternative
disposal sites evaluated in this report for
the BHNDP are also suitable for
maintenance projects if the improvement
project does not proceed. There are
differences between the project and no
project options that must be considered in
evaluating sites for disposal of maintenance
material: volume differences and
availability of clean parent material.
Maintenance projects typically remove
material from shoal areas to keep the
channels open. Therefore maintenance
dredging most likely will take place over a
longer period of time through smaller
projects than that required for the BHNIP.
Smaller capacity sites such as the shoreline
sites or lined landfills, that may be
inefficient for the higher full project
volumes, may be more suitable for use in
normal maintenance projects.
Because maintenance dredging does not
involve removal of parent or clean
material, those disposal alternatives that
depend on containment in parent material,
2-3
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such as in-channel disposal, or borrow pits
or confined aqautic disposal, are less feasi-
ble.
- Three nhannels. AH
Over the past decade various dredging
alternatives, which fuffill the project
purpose and need, have been investigated
to identify their economic and
environmental implications. The results of
these investigations are contained in the
1988 Feasibility Report. The
recommended plan, authorized in 1990,
includes the following features: deepen
Reserved Channel and Mystic River from -
35 feet to -40 feet MLW and Chelsea
Creek from -35 feet to -38 feet MLW
Also included are non-structural boundary
modifications in the Presidents Roads area.
Project berths located in these three
tributaries would also deepen their areas to
the same depths as the adjacent channel to
accommodate deeper draft ships (see
Hgure 1-3 through 1-7).
Deepening Boston Harbor will involve the
removal of approximately 2.8 million cubic
yards of silt, clay, and rock (Table 2-2).
An additional 1.8 million cubic yards of
clean parent material would be removed to
provide for in-channel disposal. Short-term
impacts from dredging will include local-
ized turbidity, and when silty material is
dredged, a temporary release of
contaminants to the water column. Rock
blasting will also have an impact on the
biota in the area immediately surrounding
the blast site. The long-term benefit from
the project is the removal and sequester of
silty material from biological resources.
As the water in Boston Harbor becomes
cleaner from additional sewage treatment,
the isolation of contaminated sediment will
also enhance the biological health of this
Harbor.
Engineering design of the project must
consider safety factors. For this reason a
ship handling simulation study was
conducted and evaluated to determine the
impact of channel improvements on the
docking masters'perception of safety. The
summary report was included in Appendix
D of the Draft EIR/S published in April
1994 The objectives of the simulation
were to provide an "as-near-to-reality-as-
possible" real-time simulation of the
proposed changes and to record the actions
and opinions of docking masters currently
working in the Harbor. Existing channel
conditions and vessel operations were
tested and compared with the project
channels and vessel operations of the same
vessels loaded to greater drafts.
Environmental and physical conditions
were held constant except for forces acting
on the more heavily laden ships. The
results of the ship simulation study ensured
the safety of the improved Harbor and
minimized the area to be dredged.
Based on the ship simulation study and the
economic analyses, the preferred navigation
improvement project, as authorized,
consists of the following components:
2.1.3.1 Reserved Channel
The existing 430-foot wide, 4,500-foot
long, Reserved Channel will be deepened
to .40 feet MLW from its existing -35 foot
MLW with the exception of its upper 1,340
feet which wUl remain at -35 feet MLW.
The width of the project channel will vary^
The northern limit will be relocated inward
by 15 feet for the entire length of the
deepened channel, ihe southern channel
limit will be relocated inward by 32 feet
from the confluence with the mam snip
2-4
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channel, along the Conley Terminal (Berths
11, 12 and 13) to the upstream limit 6?
Conley Berth 11 resulting in a width of
383 feet for a distance of approximately
2,950 feet Upstream from Berth 11 the
existing southern channel line will be
relocated 15 feet inward to the upstream
limit of the deepened channel resulting in a
width of 400 feet The 32-foot wide re-
duction in the width of the existing channel
along the Conley Terminal Berths 11, 12
and 13 will be deauthorized and become
berth area. The channel will be widened to
provide maneuvering area at the confluence
of the Reserved Channel, Main Ship Chan-
nel and Drydock Channel, and deepened to
-40 feet MLW, relocating the established
harbor lines accordingly. A trapezoidal
area of the -35 foot main ship channel,
opposite the Reserved Channel, will be
deepened to -40 feet to provide required
maneuvering area.
Approximately 159,700 cubic yards (cy) of
silty (maintenance) material and 438,800
cy of parent (new) material will be
removed from the channel. Approximately
34,100 cy of rock will be blasted and
removed in the maneuvering areas at the
mouth of the Main Ship Channel. The
Conley Terminal berths 11-13 and the
Coastal Oil berth are direct project
beneficiaries required for the improvement
project Approximately 45,900 cy of
material will be removed from the Conley
Terminal berthing area 11-13 to deepen it
to -40 feet MLW. The Coastal Oil berth
has been deepened recently and does not
require dredging. The following berths do
not receive direct benefit from the BHNIP:
Boston Edison Intake and Barge Berth,
Conley (Berths 14-15), and Boston Army.
These berths will remove about 152,800 cy
of total material. Dredging of the North
Jetty berth on the Main Ship Channel will
generate about 16,200 cy of material. The
total amount of dredged material to be
reifioved from Reserved Channel and
associated work in the Main Ship Channel,
including rock, is about 847,500 cy. The
volumes are detailed in-Table 2-2.
2.1.3.2 Mystic River Channel
About 5,670 feet of the existing 6,570-foot
long -35 foot MLW Mystic River Channel
would be deepened to -40 feet MLW. The
Mystic River Channel is 580 feet wide
through the Tobin Bridge, 740 to 700 feet
wide from the bridge upstream to the
Island End River, widening to 930 feet at
the Island End River, widening farther to
960 feet at the Exxon Terminal then
narrowing to 440 feet at the Distrigas pier
continuing upstream to the Prolerized
Wharf to a depth of -40 feet MLW. Areas
of the channel not requiring deepening
would remain at their authorized depth of
-35 feet MLW.
Also included with the Mystic River
channel design is the Inner Confluence
area. The existing 35-foot deep Inner
Confluence Area would be deepened to -40
feet MLW as well as about 2,500 feet of
the -35 foot Main Ship channel
downstream of the Inner Confluence. This
will improve the maneuverability of larger
vessels as part of the modification to
improve the approach to the Mystic River
Channel.
In the Inner Confluence and Mystic River
approximately 471,900 cy of silt, 791,800
cy of parent material and 54,000 cy of rock
will be removed from the Channel. This
includes deepening a part of the -35 foot
MLW Main Ship Channel just south of the
Inner Confluence.
2-5
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Three of the berth areas that are direct
project beneficiaries will be deepened to
-40 feet MLW, with the following
approximate amounts of material removed:
Distrigas, 13,800 cy; Prolerized, 7,600 cy;
and Moran Terminal, 6,600 cy. Boston
Edison who uses the Exxon berth, are
direct project beneficiaries. Exxon is
currently at the -40 feet depth and does not
need to be dredged. A berth mat is not a
project beneficiary will also be dredged.
Revere Sugar, to be deepened to -40 feet,
wfll be removing 12,800 cy.
2.1.3.3 Chelsea Creek Channel
The existing -35 foot MLW Chelsea Creek
Channel will be deepened to -38 feet
MLW, and widened to the fenders at the
bridge openings. Chelsea Creek was
investigated for deepening to -40 feet
MLW, but this depth was found to be
economically unjustified. The incremental
cost of deepening the channel from -38 feet
to -40 feet was not offset by the additional
benefit a deeper channel would provide.
The significant cost was the relocation or
protection of the subsurface utility
crossings, primarily the Boston Gas siphon.
Utilities in the Chelsea Creek Channel will
be modified to accommodate the deepened
channel. These include: Boston Edison
Cables (moved), MWRA Water Tunnels
(removed and moved), MBTA Cables
(moved), and the Boston Gas Siphon
(protected).
Approximately 230,000 cy of silt and
320,100 cy of parent material will be
removed from the Channel. The following
berths are direct project beneficiaries. The
Gulf Oil berthing area will be deepened to
-38 feet MLW resulting in the removal of
12,300 cy of material. Eastern Minerals
plans to deepen their berthing area to -38
feet MLW and remove approximately
39,900 cy of material. Northeast and
Coastal are also beneficiaries. They have,
however, already deepened their berths and
do not need to be dredged.
2.1.3.4 Main Ship Channel
Tin addition to the project tributaries, three
berthing areas along the main ship channel
will also, maintenance dredge their berths.
These berths do not receive direct benefit
from the BHNIP: Boston Army Base (1-3)
which will remove about 40,000 cy of
dredged material (of the 128,500 total for
Boston Army 1-9), about 16,200 cy of
dredged material will be removed from
North Jetty, and 17,600 cy of dredged
material will be removed from Mystic Rers
1, 2, 49, 50.
2.1.3.5 Non-Structural Improvements At
Presidents Roads
Specific Federal channel limits will be
designated through President Roads to
connect the Entrance Channels at the Outer
Confluence with the Main Ship Channel
limits. This will increase the size of the
President Roads Anchorage from 350 to
420 acres. The area will require a
hydrographic sweep survey and relocation
of several navigation buoys to ensure a
safe navigation channel. No dredging is
required.
2.1.3.6 Summary
All told, the full project (including
channels, beneficiary berths, other berths,
and related areas) will remove about
1,100,000 cy of silt, 1,680,000 cy of parent
material, and 88,000 cy of rock, all
measured in place. Because of expansion
during removal and handling, the
2-6
-------
corresponding volumes required for
disposal are approximately 1,360,000 cy of
silt, 2,020,000 cy of parent material, and
132,000 cy of rock.
In additional 1.8 million cy of parent
material will be dredged to provide in-
channel silt disposal for 1.3 million cy of
silt, allowing for 3-feet of headspace for
capping. The total parent material to be
dredged from the Federal channel is
therefore, 3.3 million cubic yards as
follows:
Mystic/Inner Confluence:
792,000 cy (for authorized depth)
1,333,000 cy (extra for in-channel)
Chelsea:
320,000 cy (for authorized depth)
447,000 cy (extra for in-channel)
Reserved/Main Ship:
439,000 cy (for authorized depth)
0 (extra for in-channel)
TOTAL:
1,551,000 cy (for authorized depth)
1,780,000 cy (extra for in-channel)
Future maintenance dredging of the
tributaries in the Full Project is anticipated
to yield 95,000 cy for the Reserved
Channel, 1,300,000 cy for the Mystic
River, and 365,000 cy for the Chelsea
Creek over a 50-year economic project life.
Approximately 1,760,000 cy of silty
material from the tributaries will require
removal and disposal at various times over
the next 50 years.
In addition to the tributary channels,
maintenance of the Main Ship Channel and
the anchorages is required to maximize the
benefits of all the interdependent projects
that support the Port of Boston. This
maintenance would require removal of
about 4,365,000 cy of material over the
SO^year design life.
2.1.4 Expanded Project
Deepening the tributary channels below the
currently authorized -40 feet MLW and -38
feet MLW can only be accomplished
downstream of the numerous Boston
Harbor Tunnel crossings, leaving the
Reserved Channel as the only tributary
capable of being dredged to greater depth.
In order to deepen the Reserved Channel,
two major steps are required First, a non-
Federal cost sharing sponsor must request
the project to the Corps to initiate an
economic feasibility study. The Corps then
determines the economic feasibility (benefit
to cost ratio) by comparing the
improvements in navigation efficiency by
providing additional depth to the cost of
implementation and maintenance. Second,
if the project qualifies for Federal
participation, Congressional authorization
and appropriations are required to complete
design and construction.
The benefits of deepening must outweigh
the cost of design and construction and
future maintenance of the increased depth
increment The cost must include the
deepening of not only the Reserved
Channel but also the Main Ship channel,
President Roads, and the Broad Sound
North Channel including Finn's Ledge. In
addition to the navigation channels, the
benefiting berths must be deepened as well
as a portion of the President Roads
anchorage. This feasibility process would
evaluate incremental depths, including 45
feet, to optimize the efficiency of the
project The 1988 Feasibility Report
included an evaluation of incremental
depths for the tributaries, beyond 40 feet,
of 43, 45, 47 and 50 feet It was concluded
2-7
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at that time that these depths were not
necessary to satisfy the needs of existing or
projected vessel traffic based on benefits
and costs then calculated. If operations at
the Reserved Channel based terminals are
expanded or changed, further analysis in
the future may be warranted. However, at
the present time, no steps have been taken
to evaluate deepening the Reserved
Channel or its approaches.
The current project was authorized in the
Water Resources Development Act of 1990
(WRDA 90). Minor changes to a project
are allowed within the discretion of the
Chief of Engineers, however an increase in
depth would be considered a change
requiring further congressional
authorization.
2.1.5 Reduced Project
The Navigation Improvement Project is
made up of improvements to three tributary
channels. The economic feasibility
analysis prepared for the feasibility report
and subsequently updated, viewed each
tributary channel and its berth areas as
individually justified. Each tributary
channel can therefore be treated as a
separate project or in any combination with
other project tributaries.
A reduced project could result from
economic justification failing for one or
more of the tributaries as a result of
increased cost or reduced benefits to the
project Economic justification is reviewed
periodically up to the time of construction.
Corps project evaluation procedures require
that a project have benefits at least as great
as project costs, or expressed differently,
have a ratio of benefits-to-cost that is
greater than or equal to one.
Another reduction in the project, a
temporary reduction, could occur if there is
a delay in one or two of the tributaries due
to changes in the project area that might
require reformulation of the authorized
plan. An example would be the
replacement of the Chelsea Street Bridge
by the City of Boston. There is interest in
reviewing the navigation channel to
consider its widening and deepening to
accommodate larger vessels. Changes of
this magnitude would require reformulation
of a plan because the benefits would
change and may require authorization by
Congress to implement Such a delay in
the Chelsea Creek portion of the project
would not impact the Mystic and Reserved
portions of the project which could move
ahead independently. Such a delay in
dredging the Chelsea Creek could
complicate the in-channel disposal option
since a portion of dredged material from
Reserved Channel will be disposed in
Chelsea Creek The lost capacity may be
made up with additional cells in the Inner
Confluence Area. Once reformulated, the
Chelsea Creek improvement could proceed.
Minor changes to channel lines and berths
would not delay the project
A reduced project may also result from
reductions in the dimensions of the project
such as minor realignment of channel lines,
berth areas, etc. Unless these changes have
substantial impact on the economic
justification of the project, or require
reformulation and reauthorization, they
should not delay or reduce the project to
any great degree. It is anticipated that a
number of these minor reductions and
possible enlargements to the project will
occur as the design is finalized.
2.1.6 Delayed Action
The present timetable is for the Boston
Harbor Dredging Project to begin early in
1997. Any delays (>4 years) in this
2-8
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schedule could noticeably increase the
impacts to shipping interests already
experienced in the Port of Boston.
Continued siltation will steadily reduce the
useable channel and ship berth depths and
could eventually create unusable and, in
some instances hazardous, conditions for
the larger vessels. Maintenance dredging
of shoaled areas would be required to
maintain navigational safety even in the
absence of the improvement project.
Reductions in the useable draft for the
project channels and berths could limit
usage by more vessels to high tide and
increase the need for lightering. Also, this
may result in a reduction in the size of
vessels transiting Boston Harbor, increasing
the overall number of vessels needed for
handling the same quantity of goods.
Vessel maneuverability could also be
impaired for larger vessels such as the
LNG (Liquified Natural Gas) tankers that
torn in the inner confluence. Constraints
on the size of vessels that could utilize the
harbor may reduce cargo volumes and
overall port employment (see Section 1.1).
A reduction in flexibility of ship schedules
could ultimately result in the diversion of
cargo to other ports. This loss in the cargo
market would have a negative impact on
the Port of Boston and the New England
economy.
The authorized depths in the port of
Boston are difficult to maintain since it is
the upper "maintenance" silty material that
contains the higher contaminant
concentrations. This makes finding a
suitable disposal site difficult The Harbor
was last dredged in 1983 and maintenance
dredging of this and other channels is now
already overdue. Delaying the project
another 5-10 years could have substantial
impacts, by increasing the quantity of
material that will eventually require
dredging, and increasing the cost A
greater quantity of material coupled with
inflation will increase the cost of dredging
without a corresponding increase in
benefits. The increased quantity will also
lengthen the duration of dredging once it
finally begins and could affect the project
schedule further if the increase in time
conflicts with environmental dredging
windows.
2.2 COMPARISON OF PROJECT
DESIGN ALTERNATIVES
Three major factors differentiate the project
alternatives: quantities to be dredged,
areas to be maintained or improved, and
the timing. The quantities of sediment to
be dredged affects:
• duration of dredging
• duration of turbidity plume
• amount of habitat affected
• duration of interference
with navigation.
The No Action without Maintenance
alternative would, of course, result in no
dredging and therefore would have none of
these effects. However, without
maintenance the siltation will interfere with
i
navigation and may cause hazardous
conditions. In turn, the alternative would
have other environmental and economic
impacts. The No Action with Maintenance
alternative would remove only
unconsolidated silt and leave the cohesive
parent material in place, resulting in
virtually the same turbidity, plume and
footprint, but reduced duration of dredging
compared to the Full Project or the
Delayed Project Because the Delayed
Project would encompass dredging a larger
component of silt, dredging would take
longer and result in a prolonged period of
2-9
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increased turbidity compared to the Full
Project.
The physical limits (both horizontal and
vertical) of the dredging alternatives affect
• socioeconomic benefits
• navigation safety
• potential improvements to
bottom sediment quality
• extent of turbidity plume
• area of habitat affected
The changing world fleet requires deeper
ports to minimize double-handling of
cargoes. The two No Action alternatives
would allow shipping to continue in
Boston Harbor but would eventually lead
to greater and greater reliance on partially
loaded vessels, lightering or feeder barges.
The No Action with Maintenance dredging
alternative has all the potential impacts of
the Full Project (because of the silt
removed) but without the economic
benefits of the full project Deepening of
any of the channels would improve this
outlook for specific components of the
Ports activities. Petroleum shipping would
be aided by dredging in Chelsea Creek,
Mystic River and Reserved Channel. LNG
shipment would be aided by activities in
the Mystic River. Container shipping
would be aided by deepening the Mystic
River and Reserved Channel. Thus, the
Rill Project has the greatest potential to
benefit shipping in Boston Harbor. These
benefits would be reduced for the Delayed
Project Delaying the project could reduce
the economic benefits if port costs or
navigation conditions cause current port
users to use other ports.
The Full Project is the preferred, and
congressionally-authorized, alternative for
the dredging project In addition to the
removal of all unconsolidated silts required
for maintenance, parent material would be
dredged to project depths. The purpose
and need for the Full Project has been
documented (ACOE 1988; and Section
1.1). It offers the greatest benefits to the
port of Boston; the impacts associated with
the dredging are, as with the other
alternatives, temporary. The preferred
project alternative can reduce the cost of
products shipped through Boston, reduce
associated shipping costs, maintain safety,
and maintain a workforce engaged in
maritime support services.
2.3 FUTURE MAINTENANCE
DREDGING
One of the primary benefits of the BHNIP
is that the navigational efficiency and
safety of Boston Harbor will be increased
and future growth of Boston, as a major
international trading port, will be
supported. This benefit cannot be fully
sustained, however, unless future
maintenance dredging within the Harbor is
performed consistently and the desired
channel and berth depths accomplished by
the BHNIP are maintained. Future
maintenance dredging of Boston Harbor
will involve the removal of the upper layer
of accumulated silt material from within
the channels and associated berths, without
the need to remove any of the underlying
parent material. The issues associated with
maintenance dredging are similar to those
associated with the maintenance material
component of the improvement project:
quantity and quality of the dredged
material; disposal site options; potential
environmental impacts associated with the
dredging operation and with the disposal of
the material; and the related costs.
The following sections discuss future
maintenance dredging for the BHNIP.
2-10
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Section 2.3.1 discusses the estimated
quantity and quality of the material which
will be removed during future maintenance
dredging. The anticipated dredging cycle,
is discussed in Section 2.3.2. Section 2.3.3
describes demonstration projects that are
being considered to assess the effectiveness
of potential disposal options for future
maintenance material. Section 2.4.4
provides a summary of disposal options for
future maintenance dredged material.
2.3.1 Quantity and Quality of Dredged
Material
The quantity and quality of the material
dredged during future maintenance cycles
will directly influence both the future
dredging cycles and the selection of
disposal options for the material. The
estimates for the quantity(s) and quality of
the dredged material, are that based on
information provided in the DEIR/S,
provide a worst case representation of
future conditions.
2.3.1.1 Quantity of Material
Estimates of the quantity of material
dredged from future maintenance activities
are based on the estimated rates of
sediment accumulation within each of the
areas to be dredged. Estimated rates are
generally determined from average
accumulation rates obtained from scientific
studies and/or observations made over
periods between dredging cycles.
Sediment accumulation rates within a
specific area are dependent upon conditions
such as sediment load to the harbor system,
tidal flow currents, flood and ebb
velocities, circulation patterns, wind and
wave action, and the physical stability of
the sediments. These conditions, in turn,
result in variable accumulation of
sediments.
The Reserved Channel and Turning Area
have an average siltation rate of less than
0.2 inches per year. The Mystic River and
the Inner Confluence have an average
siltation rate of 0.2 inches per year.
Chelsea Creek has the highest average
siltation rate of 0.8 inches per year. The
average rates, however, do not account for
the variability in shoaling rates which
would require that certain areas within
those channels/tributaries be dredged
frequently enough to produce adequate
controlling depths. The average siltation
rates within the Main Ship Channel and
Anchorages are, on average, lower man
those within the Tributaries. The siltation
rates vary from 0.03, 0.07 and 0.08 inches
per year in the 35-foot, 40-foot Main Ship
Channel, and President Roads Anchorage
area per year, respectively. Shoaling rates
within these areas are also variable.
Using these sedimentation rates, the
estimated the annual rate of sediment
accumulation in cubic yards (cy) over a
one year period for the Tributaries, the
Main Ship Channel and the Anchorages,
over the 50 year project life, are estimated
as follows:
SEDIMENT ACCUMULATION OVER
50-YEAR DESIGN LIFE OF PROJECT
BY LOCATION
TRIBUTARIES:
Reserved Channel:
95,000 cy
Mystic River:
1,300,000 cy
Chelsea Creek:
365,000 cy
2-11
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Berth Maintenance:
1,000,000 cy
Total 2,760,000 cy
MAIN CHANNEL:
40-Foot Main Ship Channel:
2,195,000 cy
35-Foot Main Ship Channel:
717,000 cy
President Roads Anchorage:
1,455,000 cy
Total 4,365,000 cy
The 50-year project life starts at the
completion of'the BHNEP. Future
maintenance dredging will continue for the
life of Boston Harbor and its use as a
commercial port Funding for future
dredging of berths, in order to fully realize
project benefits, will be provided by
individual berth owners.
2.3.1.2 Quality of Material
The Massachusetts Water Resource
Authority's (MWRA) stricter controls on
sludge and combined sewer outfall (CSO)
discharges into the Harbor, is expected to
reduce the amount of contaminants entering
the Harbor and, ultimately, improve the
quality of the water and sediments. Boston
Harbor, however, is an urbanized working
port, supporting shipping, commercial and
industrial activities. Historically,
urbanization results in measurable
degradation of the water quality and
sediments. The beneficial impacts from
the BHNIP and MWRA controls will not
be fully realized until some time in the
future. Benefits to water quality from
stricter water quality controls and the
cessation of the discharge of sewage sludge
are, however, akeady becoming apparent in
the Outer Harbor at areas around Spectacle
Island and Sculpin Ledge Channel in
studies performed for the Central
Artery/Tunnel Project (NAI 1994).
A sampling and testing program of the
BHNIP silt and sediment was conducted
and the results reported in the DEIR/S.
The program used a three tier analytical
approach for marine sediment
characterization. The three tier approach
combines a literature and existing data
review, bulk chemistry analysis of the
material, and biological testing; all of
which are used to determine if the material
is suitable for unconfined ocean disposal
(see Section 2.2.1 of the DEIR/S).
Based upon the results of the sampling and
testing program, the EPA determined that
the silt material was unsuitable for
unconfined ocean disposal. As water and
sediment quality are expected to improve
over time, some silt, especially from the
Main Ship Channel, may be suitable.
However, as a worst case scenario for
calculating future maintenance dredging
quantities, it is assumed the dredged
material will not be suitable for unconfined
ocean disposal and that alternative
disposalmethods will be required.
2.3.2
Future Maintenance Dredpins Cycle
Maintenance dredging can occur as
frequently as once every year to once every
20 to 30 years or more. The maintenance
cycle is generally established based on a
number of factors such as sediment
accumulation and conditions within the
area to be dredged; navigational status and
priority of the dredged area; depths and
widths required to produce the benefits that
the project was designed to achieve;
potential disruptive impacts 0.e biological,
socioeconomic, transportation) from the
dredging operation; availability of disposal
2-12
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options for the dredged material; and
funding for the work.
The Corps anticipates that an approximate
10 to 20 year dredging cycle, commencing
from the completion of the BHNIP, is
appropriate for planning future maintenance
dredging of Boston Harbor. Based on the
annual rates of sediment accumulation
estimated for the tributaries, Main Ship
Channel and the Anchorages, each ten year
dredging cycle would result in the removal
of about 1.3 million cy of material,
including material from required berths.
As time progresses and technologies
advance, additional disposal options for the
dredged material may emerge for disposal
of the maintenance material. For example,
technologies may render the material clean
or reduce the amount of material
considered unsuitable for unconfined ocean
disposal. These disposal, options and
technologies may become commercialized
which may reduce the costs of options
found to be impractical at this time.
Maintenance dredging of Boston Harbor is
one of many future dredging projects that
can be expected in the Commonwealth
over the next fifty years. Dredged channel
access to communities with commercial
fishing or recreational use harbors will also
need to be maintained. As mentioned in
the introduction, disposal sites for
maintenance material must be provided by
non-Federal interests. The Massachusetts
Executive Office of Environmental Affairs
(EOEA) recognizes the need for a long-
term, statewide, dredging management plan
and has asked the BHNIP sponsors to
develop information in the MEPA and
NEPA documentation that could help
advance the development of such a plan.
The Corps will be completing a
Massachusetts Navigation and Dredging
Management Study in July 1995 to provide
information on the current and projected
future dredging and disposal needs of the
State. The Commonwealth and the Corps
will continue to work together to identify
ways in which to maintain access to local
harbors, including Boston, in an efficient
and environmentally-sound manner.
2.3.3 Demonstration Projects
Two options presently being considered for
the disposal of future maintenance dredged
material are capping at open water sites
and use of geotextile containers. Both
options appear to be viable methods for
containment of the silt material; however,
unanswered questions as to their efficiency
have raised questions about their viability.
The use of demonstration projects is a
common method by which to test and
determine the effectiveness of a product or
technology. Demonstration projects are
designed to simulate field conditions or
utilize actual field sites over a period of
time and provide a realistic test of the
process or product's efficacy.
Given a project source of suitable material
within a reasonable accessible distance of
MBDS, the Corps is interested in
demonstrating the feasibility of capping.
Such a project would not be experimental
in that an actual dredging project, with
suitable material, would be used. The
demonstration phase would be monitored
which may require both Federal and non-
Federal participation. The timing of such
an operation depends on the availability of
suitable project material and funding of the
monitoring phase. The Corps does not
currently plan to demonstrate use of
geotextile bags in New England, but will
continue to evaluate other projects and
demonstrations throughout the country for
potential implementation.
2-13
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2.3.4 Disposal Options for Future
Maintenance Dredged Material
Non-Federal interests are responsible for
providing the necessary disposal sites for
future maintenance material including the
lands, easements, rights-of-way, dikes,
other containment facilities and the
necessary approvals.
Disposal sites considered in Section 4.0 of
the EIR/S for the silts from the current
project are also primary candidates for
disposal of future maintenance material.
These include MBDS with capping or other
management technology, Subaqueous sites
B and E, Spectacle Island CAD and
Meisburger sites 2 and 7. Some of these
sites may require further evaluation and
design before they are used. Capping at
the open water sites will require a
demonstration of the process.
In the next few years, as the need for
dredging of major harbors and/or ports
increases, there will be increased pressure
to find disposal options for the dredged
material. In some instances the dredged
material will be cleaner and will require no
special method for its disposal. In other
instances, like that of the BHNIP, the
maintenance dredged material will not be
suitable for unconfined open water disposal
making the process more complex.
As time progresses and technologies
advance, the number of disposal options
for future maintenance dredged material
from Boston Harbor may increase. New
technologies and discovery of new
containment materials subsequently
increase the number of sites available for
disposal of the material. The following
section briefly discusses a number of
potential options which may be available
for disposal of future maintenance dredged
material that at this time are not proven or
are too costly.
2.3.4.1 Capping
Numerous commentors on the DEIR/S
expressed the need for a demonstration
project to prove the feasibility of capping
as a future option for ocean disposal of the
contaminated silt (confined ocean disposal).
Since capping has not been demonstrated at
MBDS depths, commentors on the DEIR/S
felt there was a need to demonstrate its
efficacy. If capping proves to be an option
for ocean disposal, then the Massachusetts
Bay Disposal Site (MBDS) and other open
water sites may become viable disposal
options for contaminated sediments.
A demonstration project for capping may
be conducted at the MBDS using a clean
silt material. The demonstration project
would include point-depositing clean
material by precise positioning of the
barge. Once disposal is complete, clean
material will be deposited over the
contaminated material to form a final cap
of approximately 3 feet in thickness.
Monitoring of the demonstration site will
be conducted over an undetermined period
of time. This would likely involve
monitoring for a period ranging from one
to three years so that the cap can be
observed over different weather and
oceanic conditions (i.e. intense storms,
seasonal variations, variable wave action,
tidal flows).
The demonstration project will follow the
guidelines under the Marine, Protection,
Researach, and Sanctuary Act, the Clean
Water Act, and will require consistency
with the policies of the Massachusetts
Coastal Zone Management Agency (CZM)
under 301 CMR 20.00.
2-14
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If the demonstration project determines that
capping is an effective method for the long
term containment of silty material at open
water aquatic sites, sites where unconfined
disposal was previously a concern may
become preferred alternatives for future
maintenance dredged material. The ocean
disposal sites, including MBDS and other
open water sites, may become acceptable
disposal sites with capping. The short-term
impacts associated with the capping
process (i.e. temporary disturbance of
habitat, short-term turbidity, temporary
disruption of traffic) may continue to be a
concern at these sites, however, the long
term impacts, such as migration of
sediments/contaminants and localized water
quality impacts, will be addressed with the
use of a cap.
The capping and disposal of dredged
material at landfills will become less of an
option as time goes on. Throughout the
Commonwealth, landfill space is fast
approaching capacity and space is limited
to other, higher priority forms of solid
waste. Further, state regulations requiring
the closure of many of the landfills will
also limit the amount of landfill space
available for dredged material. Only the
more expensive option of out-of-state lined
landfills may be available.
2.5.4.2 Geotextile Containers
A new technology which is being
considered as a disposal option for future
maintenance dredged material is geotextile
containers. The containers, which are
generally composed of a pervious sheet of
woven plastic (synthetic), monofilament or
multi-filament yarn, can be filled with the
dredged material and disposed in open
water sites. These containers, which come
in the form of either geotextile bags or
"geocontainers", can range in volume up to
6jOOO cy and possibly larger depending
upon their application in a project
Geotextile containers have been used in
deepwater aquatic environments in the
United States (U.S.), Japan and Holland as
underwater dikes, breakwaters and similar
submerged structures for approximately
five years.
Many of the commentors on the DEDR/S
expressed interest in the use of geotextile
containers as a disposal option for the
BHNIP silts. There is limited information
regarding the effectiveness of the
containers, particularly when used to
contain silty material. The consensus of
the commentors was that the containers are
a feasible disposal option; however, more
information is needed to demonstrate their
suitability for future disposal of the
BHNIP maintenance material.
The Army Corps of Engineers has used
geotextile containers at two sites in the
U.S.: Red Eye Crossing on the Mississippi
River in Louisiana and Marina Del Rey in
Venice, California. At Red Eye Crossing,
the containers were filled with dredge
material and used to construct underwater
structures. The containers at Marina Del
Rey were placed in a shallow water habitat
confined aquatic disposal site. At Red Eye
Crossing, the sandy, uncontaminated
dredged material was placed in both
geobags and geocontainers. In Marina Del
Rey, the material was a silty sand
contaminated with hydrocarbons and heavy
metals. In both instances, the placement of
the containers was accomplished easily and
accurately with minimal release of
materials during placement The only
incident of leakage occurred at Marina Del
Ray when the initial container was torn
open to insert high pressure piping to
liquify the contents to aid release from the
2-15
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barge. The two projects were implemented
in 1994, so no long term monitoring
information exists to date.
Other tests on the efficiency of geotextile
containers were performed by the U.S.
Army Waterways Experiment Station in
Vicksburg, Mississippi. One set of
samples placed in geobags were shown to
release a small amount of fine-grained
material after being dropped. Other tests
to determine the effectiveness of the
geotextile fabric to contain heavy metal
contaminated materials were conducted;
however, results were inconclusive, due to
the lack of long-term studies. In April
1995 a single geotextile container was
dropped in the New York Harbor area.
Test data is still being analyzed.
A major constraint on the use of geotextile
containers is the time consuming and labor
intensive process required for their use.
The containers must be assembled, placed
onto the barge, unfolded, secured and, after
being filled, must be sewn together
properly and then placed at the disposal
site. The entire process can require up to
eight people and can take one to two hours
per container, substantially increasing the
dredge time and cost of the project
The Corps is not planning a demonstration
project in Boston Harbor using geotextile
containers at this time. Such a
demonstration would require obtaining
large amounts of suitable test material
approved by regulatory agencies. The
geotextile project also requires additional
preparation time for the containers and
scheduling of the contractor(s). A
demonstration project would need testing
and monitoring prior to construction of the
BHNEP; this would pose a serious time
constrain on the project The capping
project is preferred for demonstration and
the Corps will likely continue with plans
for such a project The Corps will
continue to evaluate other projects that use
geotextile containers and their applicability
to future maintenance of the BHNIP and
other dredging projects.
If geotextile containers prove to be an
effective and cost-efficient method for
containment of silty/contaminated material,
those sites which were considered
inappropriate for unconfined disposal
(MBDS, BLS) may become viable options
with the use of geotextile containers.
Similar to the capping process, the
containers would seal the material,
preventing its migration from the target
area. The geotextile containers may also
be capped; a method which would further
isolate contaminants from the environment
2.3.4.3 Treatment Technologies
An alternative for disposing of
contaminated dredged material would be
treatment As technologies advance in the
next ten years, and the need for treatment
of contaminated materials is realized, the
number of treatment options for future
dredged material may increase. As the
number of technologies increase so will the
options for disposal of the material.
A technology that renders the silt material
clean and suitable for unconfined open
water disposal would address the issues
regarding disposal because MBDS is
available for the disposal of clean material.
Disposal options such as land disposal or
reuse of the silty material would also be
reasonable alternatives if the material were
clean. Other technologies that could
reduce the amount of material would
increase future disposal options in that
capacity of the disposal sites would be less
2-16
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of an issue. Technologies that render the
material clean and reduce both the volume
would reduce disposal concerns and
regulatory constraints.
Currently there are commercial
technologies available that have been used
successfully on materials similar to the
BHNIP silt (see Section 3.5). The largest
constraint on the use of these technologies
for the BHNIP silt is their implementation,
cost, limited capacity to process large
volumes at a substantial flow rate, and the
by-product that still needs confined
disposal. The time frame required to
design, permit and construct a treatment
facility in Boston Harbor is approximately
2 to 4 years; a time frame beyond that for
use of the BHNIP material.
Treatment of future maintenance dredged
material from Boston Harbor, however,
may be a practicable disposal alternative.
With a commitment of funding and staff
time from resource agencies there may be
time prior to the first maintenace dredging
(ten years) for designing, permitting and
constructing a treatment facility and for
carrying out a demonstration project
Within the ten year period, other dredging
projects in the state will increase the need
for treatment thereby increasing the
pressure to construct such a facility. The
increase in the number of technologies
which may be available in ten years may
further result in decreased cost, which may
make treatment a practicable disposal
alternative for future maintenance dredged
material.
2-17
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-------
TABLE 2-1.
CHANNELS AND THE
——————_
DATE LAST
MAINTAINED
THE TRIBUTARY
MAIN SHIP CHANNEL
Reserved Channel
Mystic River
Chelsea Creek
TOTAL for
Tributaries
MAIN SHIP
CHANNEL
40-foot Main Ship
Channel
35-foot Main Ship
Channel
President Roads
Anchorage
TOTAL for Main
Ship Channel
ESTIMATED
ANNUAL RATE OF
ACCUMULATION
(cy/year)
ESTIMATED 50
YEAR1
None since
deepened in
1966
1983
1983
1,900
26,000
7,300
1974
1968
1983
43,900
14,300
29,100
95,000
1,300,000
365,000
1,760,000
2,195,000
815,000
1,455,000
4,365,000
A fify (50) year project life is used for economic evaluation and starts at the
timing of completion of the project. This table does not include future
maintenance requirements of the berths.
-------
TABLE 2-2.
\
\
- .
Reserved Channel/
Main Ship Channel
Mystic River/
Inner Confluence
Chelsea River
Subtotal
TOTAL
Federal Channel
Conley H-13
North Jelly
Boslon Army 1-9
Boslon Edison Intake
Boslon Barge Berth
Conley 14-15
Federal Channel
Prolerized
Distrigas
Moron
Revere Sugar
Mystic Piers 2, 49 & 50
Myslic Pier 1
Federal Channel
Eastern Minerals
Gulf Oil
Federal
Berths
In-silu
After removal11
632,600
45,900
16,200
128,500
1,100
16,100
7,100
1,317,700
7,600
13,800
6,600
12,800
45,200
17,600
550,100
39,900
12,300
2,500,400
370,700
2,871,000
3,471,000
34,000
0
0
0
0
0
0
54,000
0
0
0
0
0
0
0
0
0
88,100
0
88,100
132,000
438,800
18,000
7,800
0
0
10,800
2,800
791,800
5,500
10,000
0
3,100
28,700
8,400
320,100
32,700
5,400
1,550,700
133,200
1,684,000
2,021,000'
1 Rounded to nearest 1,000 cy
ensure all silt is removed.
161,600
27,900
8,400
128,500
1,100
5,300
4,300
497,900
2,000
3,800
16,600"
9,700
16,500
9,200
237,300
7,200
6,900
896,800
237,500
1,134,000
1,361,000
\
\
to be removed for in-channel disposal.
-------
-------
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-------
Chapter Three: Disposal Site Alternatives
This chapter of the FEIR/S summarizes the
screening process used to develop a short-
list of preferred disposal alternatives for
the BHNIP generated silt and parent
material. MEPA required the overall
process used to develop a short-list of
potential disposal sites, that were identified
in the DEIR/S is described in the next
section. As stated in Chapter One, the site
screening criteria were modified based on
DEIR/S comments in two key areas. The
first is the elimination of cost as a fatal
flaw screening criterion. Cost is factored
into the analysis only to assess the relative
cost effectiveness of disposal scenarios
determined to be environmentally suitable.
Stated differently, cost is part of the
practicability screening of environmentally
suitable alternatives.
The second change in site screening was
eliminating 200,000 cy as a minimum
capacity criterion. Capacity is now viewed
as only one factor in site screening and is
related to the cost of developing a site for
a given volume of disposal capacity.
The original MEPA scope required that the
BHNIP evaluate disposal alternatives
suitable for the current project needs and
those alternatives that could provide a
solution for future projects. In addition,
both MEPA and NEPA require that the
EIR/S consider the cumulative impacts of
future maintenance dredging for fifty years
after construction of the channel
improvements that are contemplated.
The remainder of this chapter responds to
the requirements for identifying a preferred
disposal alternative for the BHNIP as well
as for its maintenance dredging and other
future dredging projects. This chapter
culminates in a short-list of preferred
disposal alternatives. Each of these
alternatives is assessed against
environmental and practicability concerns
hi Chapter Four to determine a final
preferred disposal alternative.
Section 3.5 provides new material not
previously available in the DEIR/S. It
contains a description, and the results, of a
technology survey of potential treatment
and handling technologies for contaminated
marine silts. Section 3.6 provides new
information, since the publication of the
DEIR/S, regarding the possible beneficial
re-use of parent material at unlined
municipal landfills in the Commonwealth.
The chapter concludes with the screening
of disposal options and the development of
a short-list of potential specific disposal
sites. It provides a description of each site
in terms of existing environmental
conditions and describes how the sites
could be used for disposal of contaminated
marine silts. .This section culminates in a
short-list of potential sites that are
subjected to a detailed environmental
analysis and practicability screening hi
Chapter Four.
3.1 THE EVALUATION PROCESS
The process for identifying disposal sites
and alternatives involves a complex
mixture of data collection, analysis,
synthesis and judgment. The Disposal
Options Working Group (DOWG)
identified in Chapter One, assisted and
reviewed the methodology and findings of
every stage of the site selection process.
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The DOWG identified several key interests
to be served by the site selection process:
1. Recognizing the need for
responsible expenditure of public
funds as reflected hi the number of
sites assessed, the level of detail re-
quired hi data collection to assess
the sites, and the development of
disposal options which maintain a
benefit-to-cost ratio greater than or
equal to one for parent material and
the least costly, environmentally
acceptable, practicable alternative
for silt.
2. Meeting federal, state, regional and
local environmental laws and
regulations.
3. Meeting the objectives set forth hi
the Massachusetts Environmental
Policy Act (MEPA) and National
Environmental Policy Act (NEPA)
scoping guidance.
4. Providing disposal alternatives
flexible enough to allow for changes
in the project stemming from public
comments, differences in dredging
quantities, alterations hi project
limits, considerations regarding
project requirements for phasing of
dredging, and the length of time for
handling the marine sediments.
5. Satisfying project requirements in
terms of site availability, volume
(for BHNIP) and duration.
6. Attempting to contribute benefits to
long-term regional dredged material
disposal needs. The Commonwealth
of Massachusetts and various federal
and state entities have established a
goal of developing a long-term
dredged materials management plan
to simplify the process for disposing
of sediments that are not suitable for
unconfmed ocean disposal. This
plan is in the developmental stages,
however, and will not be
implementable for the Boston
Harbor dredging project. The
BHNIP can support the overall goals
of the long-range plan by providing
a screening process for site
selection, by providing baseline
information on sites potentially suit-
able for marine sediment disposal,
and by providing excess capacity for
future projects such as future
maintenance dredging hi Boston
Harbor.
7. Demonstrating a wise use of over 2
million yards of clean marine
sediments by identifying benefits for
both the short-term needs of Boston
Harbor clean-up and long-term
dredged material management dispo-
sal needs.
The Boston Harbor Navigation
Improvement Project (BHNIP) will
generate up to 3.5 million cy of marine
sediment and rock (as measured after
removal) under the preferred development
option. The materials assessment and
characterization provided in the DEIR/S
indicated that the parent material and rock
are suitable for unconfined ocean disposal
while the silt may require other options.
As stated hi Chapter One, the Corps has,
in response to EPA comments, adopted the
most conservative approach and has
assumed that all silt would be unsuitable
for unconfined ocean disposal.
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Because of the large quantity of material to
be dredged, it is assumed that parent
material not earmarked for beneficial uses
would be disposed at the MBDS. The
disposal options evaluation focussed
primarily on the silty maintenance and
berth sediments. The remainder of this
section describes the process for
identifying alternative disposal sites and
disposal options for the approximate 1.3
million cubic yards of this silt material,
which is not suitable for unconfined open
water disposal.
3.1.1 Identification of Disposal Concepts
The objectives of the disposal alternative
analysis and screening process were to:
• identify potential disposal sites
• analyze and combine sites with other
sites/technologies into disposal
options on the basis of
environmental considerations
• develop disposal options which meet
the interests identified for the
project.
The screening procedure consisted of an
iterative process involving the development
and application of evaluation criteria to a
broad list of sites to eliminate infeasible
disposal sites and to choose those that
would result in the least environmentally
damaging alternative. The ultimate aim of
the disposal alternatives analysis was to
identify a range of practicable alternatives
which could be used for the BHNIP
dredged material.
The disposal alternatives analysis process
began by identifying generic types of sites.
Identifying generic types ensured that no
disposal opportunity would be left
uninvestigated in meeting the MEPA
requirement for consideration of upland,
nearshore and open water alternatives.
NEPA requires the consideration and
evaluation of all reasonable alternatives.
In general, two broad classes of sites were
developed by the project team, Land-based
Sites and Aquatic Sites. A general
description of each category follows.
3.1.1.1 Land-Based Alternatives
Land-based disposal alternatives generally
include landfilling or landfill capping, and
confined disposal which may incorporate
habitat creation, and commercial reuse.
Use of land-based sites must comply with
a variety of federal, state, and local laws
and regulations. In addition, availability
of landfill space and capacity, the logistics
of dewatering, and the difficulties and
costs associated with transporting the
dredged material from the dredging site to
the disposal area are important
considerations in the feasibility analysis of
land-based options. Disposal options
which fit into the general land-based class
are described in the following paragraphs.
A. Landfilling
Landfilling involves the disposal of d
redged material in existing, permitted,
lined landfills or for use as daily cover. In
order to'use dredged material as daily
cover for sanitary landfills sufficient land
surface area must be available to dewater
the dredged materials to a suitable
solids/water ratio. Daily cover of sanitary
landfills has several benefits including the
prevention of landfill pathogens from being
carried offsite by animals, use in odor
3-3
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control, and as a fire retardant. For this
category, Project team personnel, and the
DOWG, developed a list of licensed, lined
landfills for further evaluation.
Once a sanitary or hazardous landfill has
met capacity and is ready to be closed,
dredged material with appropriate physical
and chemical characteristics can be used as
a final cover or cap. In addition to the
criteria for using dredged material as a
daily cover, a final cover must meet
minimum permeability standards, be
designed to support vegetation to improve
the site's aesthetics, and reduce the
potential for erosion. Application of
Boston Harbor dredged materials as
landfill cover would be a beneficial use. If
suitable, it could also result in habitat
creation. For this category the Project
team, and the DOWG, .developed a list of
former or closing landfills for evaluation.
B. Inland and Coastal Confined
Disposal Facilities
Confined Disposal Facilities (CDFs) are
engineered structures that are generally
lined and diked, and are designed to retain
dredged material solids while allowing
water to be released from the containment
area. A variety of site design features are
required for CDFs including a perimeter
retaining dike, a weir structure for release
of excess water, and the development of an
access road. Effects on surface water,
groundwater, air quality, and plants or
animals depend on the nature and
characteristics of the dredged material,
management and operation of the disposal
site during and after dredging, and the
proximity of the disposal facility to
potential receptors of contaminants.
Possible beneficial aspects of the
development of CDFs include the potential
for upland habitat creation/mitigation or
filling quarries or mines into developable
land.
CDFs are designed and constructed to be
used over a span of many years, storing
materials dredged periodically over the
design life. Therefore, long-term storage
capacity of a CDF is a major factor in
design and management. The Project team
and the DOWG identified land-based sites
which could be suitable for the
development of a CDF for further
evaluation. These sites were categorized
as inland if the immediate receiving waters
are freshwater, and coastal if the
immediate receiving waters are estuarine.
3.1.1.2 Aquatic Alternatives
Aquatic disposal is generally accepted for
marine dredged material if environmental
data indicate that water column and benthic
effects are acceptable. If the water column
or benthic effects are unacceptable under
an open-water, un-capped scenario, aquatic
disposal with restrictions may be
considered. These restrictions involve
disposal techniques such as capping and
confined aquatic disposal that will reduce
water column and benthic effects.
A. Shoreline Facilities
Nearshore aquatic habitats could be created
as a result of shoreline containment area
construction. Typically, this would
involve direct placement of dredged
material into existing shallow or intertidal
sites to create new habitats. The types of
beneficial habitats which can be created are
intertidal wetlands (restoration and
creation); migratory and nesting areas for
3-4
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waterfowl and shorebirds; and various
underwater habitats such as reefs, shellfish
beds, and seagrass meadows. In Boston
Harbor, the use of abandoned piers as
containment areas may also provide the
benefit of capping potentially contaminated
materials hi place. Bulkheads or other
containment structures may be necessary at
many shoreline facilities to confine the
dredged material on-site.
The nature of the dredged material, the
benefits gained from the new habitat
versus the lost benefits associated with the
old habitat, and the stability of the site are
issues that need to be considered for these
shoreline facilities. If the material is of
unacceptable quality or the site of the
dredging is a great distance from the site
of beneficial use, reuse of the dredged
material may not be practical. The Project
team and the DOWG identified several
shoreline sites in Boston Harbor which
may be created or enhanced by the
placement of some portion of the BHNIP
dredged material.
B. Subaqueous Depressions and
Borrow Pits
Existing subaqueous depressions (e.g.,
historic sand and gravel mined coastal
areas) or created borrow pits can be used
for disposal where the walls of the
depression or pit provide lateral
containment of the dredged material.
These sites can range in size from a few
feet to tens of feet deep and from a few
acres to many hundreds of acres in size.
Dredged material could be disposed of hi
depressions or borrow pits as long as the
location is suitable for capping. The cap
would be designed to. prevent potential
contaminants from entering the water
column or the food chain. The selection
of sites on which to locate borrow pits
needs to be based on an evaluation of
potential environmental, hydrodynamic,
economic, social, and cultural/historic
impacts on the Boston Harbor and
Massachusetts Bay region. The use of
depressions and pits would reduce the
lateral extent of a disposal operation,
thereby reducing both physical benthic
effects and the potential for release of
contaminants.
The project team and the DOWG identified
several subaqueous depressions and
potential borrow pit sites in Boston Outer
Harbor for inclusion in the list of sites for
screening.
C. In-Channel Disposal
In-channel disposal consists of excavating a
trench within the navigation channel limits
into the parent material, filling the trench
with contaminated silts, and using granular
materials as capping material. The
configuration of the trench would be
designed so, that upon completion of
filling and capping, final contours would
match the previous or improved harbor
bottom contours. This alternative has the
advantage of being located hi an already
impacted area (i.e., the navigation
channels) although water quality and
biological impacts as a result of the double
handling of dredged materials would need
to be carefully evaluated. The project
team and the DOWG identified several
sections of the Boston Inner Harbor
navigation channels where In-Channel
disposal may be feasible.
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D. Existing Ocean Disposal Sites
Shallow ocean disposal sites are generally
designated sites on the continental shelf.
This practice consists of placing silty
material in the disposal area and then
rendering the material immobile by
capping it with "clean" dredged material.
The placement of clean material over
material considered potentially harmful is
subject to careful monitoring during
placement and after closure. The cap is
intended to isolate contaminated sediments
from the water column. The cap would
prevent or reduce the accumulation of
potentially harmful constituents in the
water and biota of the disposal areas, and
avoid the potential for long-term (chronic)
impacts that might occur if the dredged
material were left exposed to the natural
environment. The resulting disposal site
would be a mound of dredged material
above the ambient ocean floor. This
alternative may be feasible at previously
used dredged material disposal sites, such
as the Boston Lightship Disposal Area.
The Massachusetts Bay Disposal Site
(MBDS), located approximately 20 miles
off the Massachusetts coast, has been used
for unregulated ocean disposal activities
prior to the 1970s. The MBDS has
recently received site designation status as
an EPA approved national disposal site.
The continued use of the disposal site
would center potential impacts on existing
disturbed habitats, protect the existing
biological conditions hi other undisturbed
areas hi the Massachusetts Bay, and lessen
potential conflicts between interested
parties.
The MBDS would receive the parent
material and rock remaining after
beneficial uses have been completed. The
sediment characterization performed for
the Project indicates that this material is
suitable for unconfmed, ocean disposal.
The silt material from the project has been
determined as unsuitable for unconfined
MBDS disposal, either capped or
unconfined and therefore, this site is
dropped from further consideration for this
project. It's use for the disposal of future
maintenance material will require
additional studies, demonstration projects
or both.
3.1.2 Identification of Potential Disposal
Sites
As a starting point for identifying disposal
alternatives, a wide range of sites were
developed from a number of sources to
create a "universe" of sites from which
potential disposal areas could be extracted.
The sources for the universe of sites
included potential disposal sites from the
Central Artery/Tunnel Project, the MWRA
Residuals Management Facilities Plan
(Black and Veatch 1987), Massachusetts
Bay Disposal Site Designation, an EPA
study on nearshore disposal facilities
(Metcalf and Eddy 1992), and conversa-
tions with local, state and federal agencies.
The process through which these
conceptual disposal alternatives were
evaluated, and by which specific sites were
identified, and evaluated, is detailed in
Appendix E of the DEIR/S. A summary
of the process is provided herein.
5.7.2.7 Phase 1 Site Screening
The BHNIP disposal site evaluation
process consisted of three phases. The
Phase I screening process was limited to
identifying fatal environmental impact
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flaws of particular sites. These fatal flaws
included:
• water supply wells located on a site
• sites within a sole source aquifer
• sites within the estimated habitat of
rare and endangered species
• sites in or abutting state parks
• sites within Areas of Critical
Environmental Concern (ACECs)
• sites containing a 2 IE hazardous
waste property
• upland sites with less than 15 acres
of developable land
Landfills were first screened against
requirements for accepting dredged
material and for being permitted for use
until at least 1996. Disposal and
stockpiling capacity and distance from the
dredging locations were also used as
screening criteria on those landfills that
met the first two criteria.
Sites were categorized into land-based and
aquatic sites. Land-based sites included
inland and coastal sites and landfills.
Aquatic sites included shoreline facilities,
subaqueous depressions, borrow pits, in-
channel trenches and existing open water
disposal sites. The universe of sites in all
categories that made up the first phase
screening process consisted of the
following:
• 312 land-based inland and coastal
sites;
• 21 landfills; and
• 21 aquatic sites
An additional 22 sites within the various
categories were identified in consultation
with the DOWG and agency personnel.
This consultation also resulted in limiting
disposal site selection to sites within the
Commonwealth. As stated earlier, the
MEPA scope indicated an interest in using
the information gained hi this project to
help resolve regional long-term dredging
disposal needs hi the Commonwealth.
The Phase 1 screening resulted in the
following number of sites remaining as
potentially suitable for disposal purposes:
• Land-based inland - 14
• Land-based coastal - 12
• Landfills - 4
• Aquatic shoreline - 10
• Subaqueous depressions - 6
•• Borrow pits - 4
• In-channel trenches - Not
identified or screened hi Phase 1
• Existing open water sites - 2
The list of sites remaining after the first
phase site screening (Table 3-1) were
presented at a meeting of the DOWG on
January 25, 1993.
3.1.2.2 Phase II Site Screening
Phase II screening consisted of evaluating
potentially acceptable disposal sites against
objective criteria relevant to the environ-
ment and physiography of the site.
Criteria were used that reflected regulatory
guidelines (e.g., 404 (b)(l) dredge and fill
guidelines; Clean Water Act, Massachu-
setts Coastal Zone Management regula-
tions) and requirements, (especially
Massachusetts's Wetlands Protection Act
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and Site Suitability Criteria for Solid
Waste Site Assignments). Criteria recom-
mended by DOWG participants or
identified in other dredged material
disposal site screening documents (e.g.,
Metcalf and Eddy 1992) were also
included.
While each criterion is important, certain
criteria stand out from the list as potential
deciding factors hi the site screening
process. To aid hi discriminating between
the most important and less important
criteria; each criterion was assigned a "P"
(priority) or an "S" (standard)
classification. "Priority" criteria are those
that require compliance with a specific
regulatory criterion. Inability to meet
priority criteria could become a fatal flaw.
"Standard" criteria are important to the
overall evaluation of a site's suitability but
do not rise to the level of the most
stringent standard or, represent a
potentially fatal flaw. Categorizing the
criteria into P and S groupings enabled a
semi-quantitative screening in addition to
the standard qualitative analysis.
Phase n criteria were applied to all sites
identified as potentially feasible after Phase
I, as well as several additional sites
identified with the assistance of the DOWG
(see Table 3-1). A semi-quantitative
evaluation of sites was performed for each
disposal site category. Within each
disposal site category, site "scores" were
compared to focus attention on the most
promising sites. Criteria that were not met
were examined carefully to evaluate
whether the concern could be avoided or
reduced through site planning and
management, or readily mitigated. Data
for all sites were examined both
quantitatively and qualitatively before
determining whether a site should be short-
listed.
The results of the Phase n screening were
presented to the DOWG on April 15,
1993. Discussion at this meeting and
subsequent investigations revealed addi-
tional information and issues regarding
many sites that resulted hi further
modification of the short-list (Table 3-1).
In particular, the elimination of Rowes
Quarry (MAL-01) at the end of the Phase
n screening raised considerable comment
in Working Group meetings because this
site had been short-listed by MWRA for
landfilling sludge from the Deer Island
wastewater treatment facility.1
Several agencies commented that Rowes
Quarry had been dropped from the list of
potential disposal sites hi the DEER/S
without adequate explanation. The project
team revisited the site, reviewed the
existing information on the site, and has
identified several technical, environmental,
social, and permitting issues that detract
from the suitability of Rowes Quarry for
silt disposal. These issues are discussed
below.
USEPA. 1990. Public record of decision on the
"Final Supplemental Environmental Impact
Statement, Long Term Residuals Management
for Metropolitan Boston". U.S. Environmental
Protection Agency. Boston, MA.
3-8
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A. Technical
According to a technical report2 rebutting
MWRA's selection of Rowes Quarry as a
potential residuals landfill site, the quarry
is characterized by exposed fractured
bedrock, with groundwater within 1 to 3
feet of the ground surface. Groundwater
was also observed discharging from the
exposed northeast quarry wall about 30 to
40 feet above the floor, and standing water
is present in portions of the quarry, due in
part from groundwater. MWRA had
determined that the quarry site is
hydrologically linked via surface water
drainage, and possibly groundwater
through the bedrock fractures, with the
adjacent Rumney Marsh. This 1,070-acre
salt marsh is located at the confluence of
the Pines and Saugus Rivers, and is
considered an extremely valuable regional
resource, as indicated by its 1988
designation as an Area of Critical
Environmental Concern.
Converting Rowes Quarry to a lined
landfill for BHNIP silts would require
compliance with Massachusetts Department
of Environmental Protection (DEP)
regulations for siting and constructing a
solid waste landfill (310 CMR 19.000).
Several unconventional engineering
techniques would be necessary to
overcome the construction constraints
imposed by the bedrock fractures, exposed
bedrock, high groundwater, and vertical
quarry walls. NEI (1989) calculated that
356,000 cubic yards of fill would be
required to prepare the quarry prior to
liner installation. Because no soils exist on
the site, the entire fill quantity would need
to be transported to the quarry in an
estimated 17,800 truckloads. Assuming
the constructed landfill would be 30 acres
in size on the 43-acre site, the silt capacity
is estimated to be 484,000 cubic yards (or
24,200 truckloads). Therefore,
constructing the site would require
importing three-quarters the amount of
material the landfill would eventually
accommodate.
A portion of the estimated 356,000 cubic
yards of fill required to prepare the quarry
floor for a landfill could potentially be
obtained from the BHNIP parent material.
Some mixing with clean material will be
required to reduce the chloride
concentrations in the BHNIP material to
acceptable levels for terrestrial use.
Chloride concentrations in the berth parent
material averages 1.8% (BHNIP DEIR/S,
Volume 2, Appendix C-3), which converts
to approximately 8,000 - 18,000
/tmhos/cm conductivity. The Bureau of
Waste Prevention Policy 94-037 currently
sets a maximum allowable conductivity of
4,000 Atmhos/cm. A dredge material
disposal policy currently under
development is likely to set an even
stricter threshold (Joel Hartman, MA
Division of Solid Waste, personal
communication). The amount of mixing,
and thus the quantity of BHNIP material
that can be beneficially used as part of the
fill material will need to be more fully
addressed should this site ever be used for
marine material disposal.
NEI. 1989. An independent
assessment of the selection process
for MWRA residuals landfill in the
greater Boston area. Normandeau
Engineers, Inc., Concord, NH.
Prepared for the City of Revere, MA
24 pp + App.
B. Environmental
Rowes Quarry's proximity to the Rumney
Marshes ACEC will probably require
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extensive studies of the marsh and estuary
in order to determine the risk to the ACEC
from the landfill should the liner or
leachate collection system fail. These
studies are likely to include calculations of
the probability and frequency of several
design failure scenarios, estimates of both
acute and chronic levels of contamination,
and the probable fate of contaminants in
the ACEC, as well as hydrologic testing
and modeling to understand the ground and
surface water connections between the site
and the ACEC. The time and costs
required to complete these studies and the
difficulty of designing, building, and
permitting a secured disposal facility
makes the option prohibitive.
C. Social/Economic
The high densities of residences and
sensitive receptors (including several
schools and a nursing home) hi the
immediate vicinity of Rowes Quarry are
also a strong deterrent against the use of
this site. NEI (1989) reported over 12,000
residences within 1 mile and 2,500 within
one-half mile. In the 7 years since the
report, the population numbers have likely
increased due to the high development
pressures in the surrounding communities
of Maiden and Revere.
The quarry owner has consistently rejected
any discussion of selling Rowes Quarry,
which would require BHNIP to take this
site by eminent domain. This approach is
objectionable to the Project team because
of both the loss of a thriving business and
the associated jobs, and the length, and
expense of the eminent domain process.
The cost to buy the property is estimated
to be 5 to 14 times higher than the other
possible sites.
D. Permitting
The permitting process for Rowes Quarry
will likely be disproportionally long and
complex compared to most other sites on
the current disposal options list. This is
due primarily to: 1) its proximity to
Rumney Marshes ACEC; 2) its location
straddling the Maiden/Revere corporate
boundary, which would necessitate
permitting hi both towns, and; 3) the
surrounding high-density residential
population which voiced opposition to the
use of the quarry by MWRA because of
nuisance issues and the likelihood of a
decline in property values. Additionally,
as described above, obtaining the property
by eminent domain could result hi lengthy
court proceedings. Some or all of these
permitting obstacles would result in
delaying the BHNIP well into the future.
E. Future Maintenance
In light of Rowes Quarry's current siting
limitations, this site may be a more
reasonable disposal option for future
maintenance dredging material because
several major obstacles may be eliminated
or reduced in magnitude over time. The
owner of the quarry stated in 1989 that the
quarry resources will be exhausted within
the next several decades (NEI 1989). At
that point, the quarry operation will cease
and the owner may be more amenable to
selling, which would eliminate two BHNIP
concerns of interrupting an active business
and taking the property by eminent
domain. Also, technological advances may
improve the dewatering techniques
currently available, which will make all
land-based disposal options more available
in terms of both environmental impacts
and costs. In such a case, Rowes Quarry
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may be an advantageous disposal site
because of the quarry's proximity to
Boston Harbor. Finally, designation of the
site for future maintenance disposal would
allow sufficient time to complete the
anticipated lengthy permitting process well
hi advance of the need for the site.
3.1.2.3 Phase III Site Screening
Phase HI involved the development of
additional site-specific information for the
short-listed sites through site visits, aerial
photographs, and discussion with
appropriate resource agencies. The short-
listed sites were re-evaluated against the
Phase n criteria in light of the additional
information resulting in a revised short-list
(see Table 3-1).
3.1.2.4 Phase IV Site Screening
In response to comments received during
the DEIR/S public comment period, two
areas of additional information were
identified that would benefit the site
selection process. These included: 1)
water resources at the land-based inland
sites; and 2) biological conditions at the
aquatic sites, excluding MBDS. The
following sections discuss the additional
data acquisition efforts undertaken by the
project partners to further screen the short-
listed sites remaining after the Phase IE
screening.
A. Review of Phase n Evaluative
Criteria for Land-based Inland Sites
Additional information was collected to
review selected Phase n Evaluative
Criteria for Land-based Inland Sites.
Information was obtained from
Massachusetts DEP representatives
regarding public water supplies. A
Normandeau representative also visited the
DEP Northeast regional office to review
the DEP Water Supply Protection Adas
and the Bureau of Waste Site Cleanup
(BWSC) Resource Maps. Individual
BWSC Resource Maps were obtained for
all fourteen Land-based Inland Sites.
Normandeau obtained information on
public water supplies from the DEP
regional offices. Mr. J. Otavio Paula-
Santos of the DEP, Division of Water
Supply in Boston provided Normandeau
with the "List of Public Water Supplies
and Their Sources" for DEP Northeast
Region. Mr. Larry Dane (DEP Southeast
Regional Office in Lakeville, MA)
provided a listing of towns hi the DEP
southeast region which have surface water
supplies and their surface water sources.
Mr. Dave Erickson (DEP Northeast
Regional office in Woburn, MA) informed
Normandeau that the Massachusetts Water
Resource Authority (MWRA) supplies
water to most of the Boston Metropolitan
area. The second largest water supply
source is the Merrimac River upstream of
the Lawrence Dam. Additional surface
water supplies include the Hobbs
Brook/Stony Brook Reservoirs along Route
128 and also the Concord River.
A Normandeau representative visited the
DEP Northeast Regional office hi Woburn,
MA on December 9, 1994. The purpose
of this visit was to review the DEP Water
Supply Protection Atlas and the DEP,
BWSC Resource Maps relative to the
Phase II Evaluative Criteria concerning
surface water and groundwater resources.
Information that was collected from the
regional offices was used to re-evaluate
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certain screening criteria and to evaluate
those criteria which were previously listed
as "undetermined" (see Appendix E,
DEIR/S), meaning that information for a
particular site was not available.
The re-evaluating confirmed the screening
of the 14 inland, sites. The only change
occurred at the Wrentham site (W-495).
The DEP, BWSC Resource Maps show
that the W-495 is located within a DEP
Zone II Wellhead Protection Area.
B. Additional Sampling hi
Marine/Coastal Habitats Since Draft EIR/S
Additional sampling at nearshore aquatic
and marine sites was conducted hi October
1994 (see Appendix E). The sampling
plan was reviewed by Federal and State
resource agencies and modified in response
to agency comments. The purpose of the
sampling was to add an additional data
point to the body of information already
existing and used hi the DEIR/S and to
confirm or refute the earlier findings.
Nineteen locations hi Boston Harbor and
three locations on Massachusetts Bay were
surveyed using a sediment profile imaging
(SPI) camera. Samples were collected for
benthic infauna at each location using a
0.04 m2 Van Veen grab. The dredging
and disposal sites surveyed hi this study
are shown hi Table 3-2.
A finfish resource evaluation was
conducted hi October and November 1994
(see Appendix E). Demersal fishes were
collected using a nine-foot otter trawl with
a 0.64 cm cod end mesh at the six stations
shown hi Table 3-2. Three trawls, lasting
either 5 or 20 minutes (depending on
conditions) were made at each location.
Gill nets were utilized to collect demersal
fish at eight stations, including the four
dredge or disposal sites listed in Table 3-2.
Scientific gill nets measuring 30.3 m x
3.03 m with varying mesh sizes were set a
surface and bottom depths for a total of 72
hours, and were fished at a 24 and 48 hour
interval.
Lobster resources were assessed through a
trapping program (see Appendix E).
Modified lobster traps (escape vent closed)
were set at three offshore, one outer
harbor, and nine inner harbor locations.
These included the dredge and disposal
sites listed on Table 3-2. Traps were
harvested every twenty-four hours for a
three-day period in October 1994.
Lobsters were measured, sexed, and
enumerated.
The results of these sampling events are
fully discussed hi Chapter Four of the
FEIR/S and were factored into the
environmental assessment of each potential
aquatic disposal site. The sampling reports
fish, benthic, and lobster resources are
included as Appendix E (see Volume 3).
The findings of the October 1994 sampling
confirm the earlier data gathered hi
sampling programs conducted hi July and
November 1986 and April 1993, as
summarized in the DEIR/S.
32 SEDIMENT/SITE MATCHING
As stated in the original MEPA scope and
the 1988 Feasibility Report, ocean disposal
(Massachusetts Bay Disposal Site) is the
preferred disposal option for
uncontaminated marine sediments of accep-
table quality and is the option against
which other alternatives were originally
evaluated. However, a substantial
component of this project has focussed on
the issue of quantifying the levels of metals
and organics in project sediments. Review
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of these results has indicated a wide range
of chemical concentrations in sediments
throughout the project area (Section 2.2
and Appendix C of the DEIR/S). Charac-
terization of sediments for disposal options
relies on interpretation of the results of
bioassessment in terms of ecological
significance, and is, therefore, not a
clearcut decision. The Corps has joint
responsibility for making this determi-
nation. The EPA has veto authorization
The silt from the Reserved Channel area
was the only material for which a
consistent opinion was not reached.
However, based on public and agency
comments on the DEIR/S, and to ensure
that the disposal option alternatives
analysis would identify sufficient space, it
has been concluded that alternatives to
unconfined ocean disposal would have to
be sought for all silt materials from the
project.
Potential impacts arising from disposal of
the silt vary among the generic alterna-
tives. These differences are reflected in
testing requirements and required control
measures (Table 3-3). All disposal types
evaluated require bulk chemical analysis of
most parameters identified in the "Green
Book" (EPA/ACOE, 1991). Unconfined
open water disposal and lined and unlined
landfills, each have identified thresholds
for a suite of parameters that must be met
for disposal to be permitted (Table 3-4).
Thresholds for non-landfill upland disposal
are not currently established; however, site
suitability was evaluated assuming that
such a facility would be lined and that the
Category A (lined) landfill criteria would
be appropriate.
Similarly, regulatory thresholds for in-
harbor or coastal containment have not
been defined. Both alternatives would
provide isolation of the disposed material
from the surrounding environment once
disposal is complete. The in-harbor
containment alternative provides the
opportunity for isolation during disposal.
It was assumed that there were no
sediment quality thresholds necessary for
in-harbor containment or open-water
containment, but that either alternative
would be dependent on achieving accept-
able water quality conditions as
demonstrated by acceptable water quality
modeling results or monitoring. Stability
of the disposed material after emplacement
on the bottom would also have to be
addressed.
In response to agency and public
comments received on the DEIR/S, and to
address these latter issues of water quality
impacts and sediment stability, the project
team performed extensive studies hi
preparation of this FEIR/S. The first was
a series of models to determine the
transport and fate of silt disposal at the
aquatic short-listed sites. The results of
these models are used in Chapter 4 in
evaluating impacts among the short-listed
sites. The complete water quality
modeling report appears as Appendix F in
Volume 3 of the FEIR/S.
The second series of studies included a
characterization of near bottom water
velocities generated by typical vessel
operations in the improved Boston Harbor.
This study, and other studies on sediment
stability, are included in Appendix G in
Volume 3 of the FEIR/S. This
information is used in evaluating the need
for armoring and stabilizing sediments
disposed under aquatic conditions in the
Inner and Outer Harbor.
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In sum, site-specific sediment data were
compared to thresholds for each disposal
alternative (Table 3-5). Clay and rock
from all dredging areas were acceptable
for any type of disposal, provided capacity
was available. The following section
discusses how silt material could be
managed for each of the generic disposal
options, including special handling or
design features required for disposal, with
the least environmental impact.
3.3 SUITABILITY OF GENERIC
TYPES OF DISPOSAL
ALTERNATIVES FOR
DREDGED SILT
The types of impacts associated with
disposal of dredged materials can be.
categorized generally as habitat loss or
alteration, water quality degradation,
emigration (physically or biologically) of
contaminants from the disposal site, and
socioeconomic concerns (primarily fishing,
land use and traffic) and are related to site
preparation and management activities.
The following paragraphs summarize the
site preparation and management re-
quirements needed for each generic
disposal alternative to minimize these im-
pacts. The findings are summarized on
Table 3-6.
3.3.1 Land-Based Alternatives
A. Inland and Coastal Sites
In general, upland sites would have to be
cleared and graded before construction of a
silt containment facility. The containment
facility would include a liner, diked
disposal cells constructed in sequence,
runoff and leachate controls, and access
roads (Table 3-6). Closure of the site
would include capping and landscaping.
Configuration of the containment facility
would be designed to minimize impacts to
critical environmental features.
Locations of upland sites are shown in
Figure 3-1. Access to inland sites is
restricted to truck or rail transportation.
Coastal sites could be accessible by barge,
although this could require dredging of
access channels.
Potential impacts associated with
developing an upland (either inland or
coastal) disposal facility are, hi contrast to
landfills, relatively severe (Table 3-7).
While it would be desirable to focus on
previously degraded sites, areas that have
received other waste materials are not
always suitable for disposal facility
development without remediation first.
While chemically-degraded sites may be
suitable for a long-term future regional
facility after remediation, sites that have
experienced habitat alteration (clearing,
excavation and mining) are the most likely
candidates available for the BHNIP.
Development of a disposal facility on such
a site could result in loss and/or alteration
of terrestrial habitat (particularly
Wrentham (W-495) and Woburn (WOB-
11)), possibly including wetlands. Loss of
vegetated wetland habitat (Table 3-8)
would occur with development of the
Wrentham (9 acres), Woburn (1 acre) and
Squantum Point (QUI-03) (0.3 acres) sites.
Everett (EVR-04), Squantum Point and
Wrentham all provide habitat for state-
listed species of special concern (Table 3-
8).
Development of the coastal sites (Everett
and Squantum Point) would affect marine
resources due to dredging. Prevention of
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water quality impacts would depend on site
design features including design criteria to
minimize the risk of exposure of
freshwater resources to elevated chloride
levels (inland sites only) or contaminants.
Marine waters could experience locally-
elevated turbidity and contaminant
concentrations at the dewatering site
(Mystic Pier or North Jetty) for inland
sites, but this would be limited by proper
design and monitoring. Depending on site
access, use of coastal sites could affect
marine water quality during site
preparation (dredging for barge access) or
dewatering (for truck transportation). Both
inland and coastal sites offer some risk of
contaminant emigration due to the
prolonged period required for drying the
sediments before capping. Although the
disposed materials would remain azoic, the
containment area would appear pondlike
and may be attractive to birds.
Both types of sites could have socio-
economic impacts - displacement or
alteration of land use and high truck traffic
volumes. None of the short-listed sites are
currently hi use except Woburn which has
a closed, but uncontained, municipal
landfill onsite. Due to its large capacity,
Wrentham would experience the highest
truck volume but its proximity to major
highways would minimize the
neighborhood effects of this traffic. Rail
access could become available for
Woburn. Barge transport would be likely
for Everett and Squantum Point.
Disposal of silty sediments from Boston
Harbor in an upland area would remove
this associated chemical load from the
harbor environment (Table 3-9). A
regional facility might be able to use a
chemically-degraded area, but the remedial
actions necessary to develop such a site
would be greater than a single project
(even a large one) could bear. Thus, such
sites were not short-listed although any
upland site that demonstrated merit for
potential development would require a
preliminary assessment, as a minimum, for
hazardous materials. Parent material
(clay) could be used in construction of the
site, although the silt would then have to
be stockpiled during construction. There
would be potential for enhancement of
terrestrial habitats once the facility was
closed. Any landscaping would have to
preserve the integrity of the cap, probably
eliminating the planting of trees.
B. Landfills
Existing landfills can provide disposal
space for marine dredged materials under
two scenarios - use for daily cover or
burial. In the case of the BHNIP, the
surficial silts would have to be mixed with
clean materials to meet the regulatory
thresholds for daily cover.
No special site modifications would be
required for landfills, although all the
short-listed landfills have odor limitations.
Three existing landfills (Figure 3-1),
Plainville/Laidlaw, East Bridgewater and
Fitchburg/Westminister, were identified as
having the ability to accept marine
sediments in the approximate time frame
for the BHNIP.
From a qualitative perspective, use of lined
landfills for disposal of dredged materials
provides the least environmentally
damaging alternative (Table 3-8) because
the natural environment has already been
disturbed to develop the landfill.
However, competition for space at landfills
is a key issue. Landfill space is fast
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approaching capacity, and while various
landfills are capable of handling marine
sediments, this type of use could displace
other, higher-priority uses. Of the 122
landfills currently permitted to accept
municipal solid waste in Massachusetts,
114 are scheduled for closure by 1996
(DEP, January 1993 active MSW landfill
list). The three sites short-listed have
limited capacity for burial of dredged
material (Table 3-8). The exception is that
there continues to be a need for daily
cover and final closure material. Dredged
material can be suitable for these purposes
under some circumstances. To be used for
daily cover, sediment must have contami-
nant levels within a range that, after
mixing with a "reasonable" amount of
clean material, would meet TCLP
regulatory levels (Table 3-4). Maximum
need for daily cover that could be provided
by BHNEP dredged materials ranges from
50 cy/day (Plainville/ Laidlaw) to 250
cy/day (Fitchburg/Westminister) (Table 3-
8). Only clean material that would
contribute to construction of an
impermeable layer could be used for a cap.
Marine clay can be suitable for this
purpose (S. Lipman, MADEP, 1993, pers.
comm.). The limited available capacity
for dredged materials at these landfills
would minimize the traffic burden
associated with the BHNIP.
The benefits (Table 3-9) of using landfills
for disposal of marine sediments are
relatively high, primarily because this
alternative utilizes existing facilities.
Again, however, this apparent benefit must
be weighed against the constraint of
competing uses for a limited resource.
3.3.2 Aquatic Alternatives
A. Shoreline Facilities
There are two fill alternatives proposed for
the Mystic Pier sites, Revere Sugar,
Amstar and Cabot Paint (see site locations
Figure 3-1). The first alternative is for
partial fill which would result in a final
elevation (including cap) of mean low
water. The total fill alternative elevation
would be mean high water (or higher
where adjacent land elevations would allow
it). For both alternatives, a bulkhead
would be constructed to isolate the site
from the harbor during disposal. The
bulkhead would remain in place after
disposal in the total fill alternative but be
cut off at MLW after the cap was secured
for the partial fill alternative.
Two fill alternatives were considered for
these sites since the cost of disposal site
development can only be offset by
maximizing the disposal site capacity.
However, the total fill option creates an
irretrievable loss of subtidal habitat by
replacing it with fast land. The partial fill
option is designed to allow for the
establishment of intertidal habitat.
Little Mystic Channel and Reserved
Channel (Figure 3-1) would require
maintenance of aquatic habitat. Little
Mystic Channel would be filled to a final
elevation (including cap) of -6 to -3 ft
MLW. Fill in the Reserved Channel
would encompass either the entire area
west of Summer Street or only the western
end of that area. The western end would,
in either case, be filled to a final grade
(including cap) of +9 ft MLW, a suitable
elevation for establishing salt marsh
vegetation. The eastern portion would be
filled to a final elevation of -6 ft MLW.
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Both sites would be bulkheaded during
disposal.
Both shoreline fill scenarios would result
in loss of marine habitat, although in the
partial fill scenario loss would be
temporary (Table 3-7). Permanent habitat
losses would be highest at Cabot Paint
(total fill). Temporary habitat losses
would be highest at Reserved Channel (if
entire area used) or Little Mystic Channel
(Table 3-10). There were no marked
differences hi benthic infauna among the
six potential disposal sites, but the pier
areas (Amstar, Cabot Paint, Mystic Piers
and Revere Sugar) may provide slightly
better finfish refuge potential than the
channels (Little Mystic, Reserved) because
of the pilings. Ultimately, in the partial
fill alternative, marine habitat could be
altered from fine-grained substrate to
vegetated or rocky substrate of potentially
higher productivity (Reserved Channel,
Little Mystic Channel).
Temporary localized water quality impacts
could be minimized by appropriate site
management (e g., dredging and disposal
methodology, disposal behind bulkheads,
use of silt curtains, disposal timing) for
both total and partial fill alternatives. In
both scenarios, the disposal site would be
essentially isolated from the rest of the
harbor. The partial fill scenario could
pose a slightly higher risk of emigration of
silry sediments in the long term than the
total fill. Since the short-listed shoreline
sites are hi relatively quiescent parts of the
harbor, and thus relatively safe from
erosional currents, other forces (e.g.;
boats, biological activity) are unlikely to
disrupt the cap of the partial fill.
Land use impacts would be site dependent.
Any fastlands created would have to be
used for a water-dependent activity.
Alterations in current use would be
greatest at Amstar because of MWRA's
newly constructed floating dock (for trans-
port of Deer Island workers). Other pier
areas are not presently in use. Filling hi
the eastern portion of Reserved Channel
could interfere with the existing marina
operations. Traffic impacts would be
minimal at pier sites since sediments would
be transported by barge. It could be
necessary to use a barge and truck combi-
nation for Little Mystic Channel and
Reserved Channel because of low
clearance bridges across the entrance of
each site.
Each of these fill alternatives could result
in environmental or socioeconomic benefits
(Table 3-9). All of the shoreline sites are
likely to have or have been demonstrated
currently to contain, contaminated
sediments with elevated chemical
constituents. Either the total or partial fill
alternative would isolate these contam-
inants from the Boston Harbor environ-
ment. The partial fill scenario has the
potential to enhance the environmental
quality of the site by providing clean
substrate for benthic organisms (all sites),
or plantings to increase primary produc-
tivity (especially Reserved Channel and
Little Mystic Channel). Totally filled sites
could be developed for port-related
activities. Clay from the improvement
dredging could be used hi capping these
sites, reducing the need to transport
material to MBDS.
C. Subaqueous Depressions
Use of the outer harbor subaqueous sites B
and E (Figure 3-1) would rely on existing
bathymetric conditions to keep disposed
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A
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sediments in place. Sediments would be
transported by bottom-dumping scow.
After disposal of silt is complete, the area
would be capped by depositing granular
material over the sediments.
Use of the subaqueous depressions would
result in temporary habitat losses until
capping was complete (Table 3-7). The
disposal site footprint would be smallest at
the Winthrop Harbor site (8 acres).
Subtidal habitat would be altered by
changes in substrate texture and depth.
Some fine-grained sediments and
associated contaminants would remain in
suspension and be transported away from
the disposal site. ADDAM'S model
results indicate that the plume could extend
a distance of approximately 4,500 ft from
the disposal site and on a flood tide
potentially carry contaminants (which may
exceed water quality criteria by 2x) outside
the disposal site.
Commercially harvested clam beds on the
Snake Island flats and the Basin could be
sensitive to sediments with elevated
contaminants dispersed from a Winthrop
Harbor disposal site. Disposed sediments
would be exposed to currents for the
duration of disposal activities, presenting a
risk for further emigration and
bioaccumulation.
The model results imply that water quality
exceedences should not extend up-channel
beyond Chelsea Point in Winthrop, so the
Belle Isle Main ACEC should not be at
risk (Table 3-11). Subaqueous B and E
are exposed to higher current velocities
than Winthrop Harbor but water modeling
showed no impacts to areas of potential
exposure including the Governor's Island
flats and Deer Island flats. There would
be no land-based traffic impacts to any of
these sites, although some impacts to
navigation would occur. Restrictions
would be temporary in Winthrop Harbor
and Subaqueous B. Seasonal recreational
boating could restrict disposal operations
in Winthrop Harbor. Small boat use of
the channel passing across Subaqueous E
could also cause seasonal restrictions on
use of the site.
Using subaqueous depressions for material
disposal would isolate dredged
contaminants from the harbor ecosystem.
Another benefit associated with the
subaqueous disposal alternatives is the
ability to use project parent material for
the cap (Table 3-9).
D. In-Channels and Borrow Pits
Both In-Channel and Borrow Pit
alternatives would require additional
dredging of in-situ parent material.
Sufficient surficial material dredged from
the borrow pit areas would be stockpiled to
use as final capping material to restore the
site to pre-existing substrate conditions.
Native clay from channel deepening could
be used for the initial cap at borrow pits.
Sand, from either the parent material or
bought, would be used to cap the in-
channel areas due to the tolerances that
have to be achieved in the final bathymetry
in the navigation channels.
In-Channel alternatives would include
Chelsea Creek, Inner Confluence and
Mystic River navigational channels.
Borrow pit alternatives include Meisburger
2 and 7, and Spectacle Island CAD (see
Figure 3-1). This latter site is located in
the shallow (-10' MLW) subtidal area east
of the Island and is totally disassociated
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from the Island itself and the CA/T project
work in progress.
Both the In-Channel and the borrow pit
alternatives would temporarily remove
marine subtidal habitat from production.
There would be a greater impact at the
previously undisturbed Meisburger sites
than the In-Channel alternatives. Surface
substrates at borrow pit sites could be
altered somewhat but substrate in the In-
Channel sites would not be noticeably
different from the planned post-dredging
conditions.
Containment of sediments during disposal
for inshore alternatives is an issue
requiring mitigation to lessen the resulting
turbidity plume. ADDAM'S model results
indicate that water quality criteria
exceedences would not occur at the
offshore (Meisburger) or Spectacle Island
CAD site. Sediments would be exposed
for the duration of the disposal operation,
resulting in some potential for emigration
through current transport or biological
activity. The smaller capacities of the In-
Channel alternatives would result in
shorter periods of exposure than the
borrow pits. However, ADDAM's model
results, for the Subaqueous E site, indicate
that there could be water quality criteria
exceedences during flood tide after four
hours; and silt/clay plumes were predicted
to extend as much as 4,500 ft upstream of
this in-harbor disposal site. Because of
shallower water near the Spectacle Island
CAD site, dilution to below water quality
criteria was predicted at greater distances,
but reached that distribution level in less
than four hours.
Biological impacts could vary among the
In-Channel alternatives primarily because
of the Mystic River's value to anadromous
fish although seasonal restrictions on
disposal in the Mystic River Channel could
avoid these impacts. The offshore borrow
pit sites, Meisburger 2 and 7, support high
benthic productivity and fisheries resources
are relatively abundant. The outer harbor
Spectacle Island CAD appears to support
substantially lower benthic production. Its
location in the general vicinity of the
proposed Central Artery/Tunnel fish reef
mitigation and beach project, however,
would mean that disposal methods and/or
mitigation efforts would need to account
for the protection to this resource if it is in
place by the time the Harbor is dredged.
Additionally, special plans to avoid or
mitigate for fishing gear losses (lobster,
pots, etc.) from barge traffic or
construction activities may be necessary at
the Meisburger and Spectacle Island sites.
The In-Channel alternative would use
suitable granular material (sand and gravel)
as a capping material due to the tight
tolerances needed in the in-channel option
and the ability to reduce voids hi the cap
by using sand rather than cohesive clay.
Clay could be incorporated into the borrow
pit cap. Sediments (sand and gravel)
dredged from-the borrow pit sites during
site preparation could be used for beach
nourishment or construction, if the need
exists. Otherwise, this sediment would
have to be disposed at MBDS. The In-
Channel alternative has the advantage of
being located in an already impacted area
(i.e., the navigational channels).
E. Existing Disposal Sites
Previously-used dredged material disposal
sites, MBDS and Boston Lightship (Figure
3-1), could be utilized for the project for
silt disposal, with capping. At MBDS
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disposal of contaminated material with
capping is prohibited unless a successful
demonstration is made; with respect to the
BLDS, the Corps has successfully
demonstrated effective capping at sites
with similar depths elsewhere in New
England. A containment area would be
prepared by configuring parent material in
a specific area. Silt would be point-
deposited by accurate positioning of the
barge. Once disposal was complete,
additional granular material would be
deposited over the silt to form the final
cap.
Disposal of silty dredged materials at a
previously-used disposal site would have
impacts generally similar to use of a
borrow pit (Table 3-7). Since disposal of
the silty sediments at the Massachusetts
Bay Disposal Site is currently prohibited
by EPA without further testing, a field
program to demonstrate the effectiveness
of capping moves this site out of a
reasonable time frame for use on the
current project. Agency concerns associat-
ed with capped disposal at MBDS have
largely focussed on emigration of contam-
inants/sediments during disposal and long-
term integrity of the cap. In a recent study
by EPA (1993) ADDAM'S models were
run for the MBDS using this project's data
and no water quality exceedences were
predicted outside the site during the
disposal phase (Table 3-12). These results
were used to conclude that disposal
activities from this project (BHNIP) would
not add to impacts from the MWRA ocean
outfall at a level to cause a risk to
threatened and endangered species in the
area. ADDAM'S model results for the
Boston Lightship also indicate that water
quality criteria would not be exceeded
outside that disposal site which is half as
deep and twice as close to Boston as
MBDS. In the foreseeable future BHNIP
is the only project that could provide its
own capping material, perhaps represent-
ing the only opportunity to cap silty sedi-
ments of this volume and provide a
demonstration of this option's
effectiveness. This scenario would provide
beneficial use of all parent material
dredged from the project. Capping at the
MBDS may represent a practicable
alternative for the future maintenance
material as it is not considered imple-
mentable at this time due to the EPA and
CZM requirement for a demonstration of
its efficacy. The ability of the Corps to
perform a capping demonstration would
hinge, in part, on the availability of
suitable material.
3.4 DEVELOPMENT OF DISPOSAL
OPTIONS
As discussed previously, there are few
alternative disposal sites that have the
capacity to handle all the dredged material,
parent, silt and rock, for this project. In
addition, disposal considerations must
include the requirement of future disposal
of maintenance, (silt) material. In order to
address both the present and future
capacity needs individual disposal sites
have been combined into disposal options
which attempt to balance environmental
consequences with practicability concerns.
The volume of material requiring disposal
from the proposed BHNIP was
conservatively estimated to ensure
sufficient capacity will be provided at
disposal options. Table 2-1 presented the
estimated volumes of rock, parent and silt
material requiring disposal. The volumes
shown assume up to a 0.5 foot of parent
material is also dredged to ensure all silt
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material is removed. The volumes also
factor in a 20% expansion of silt and
parent material over in-situ volumes to
account for the water entrained in the
dredging process. Rock was assumed to
expand by 50% over in-situ conditions due
to the blasting fractures. Based on the
measured in-situ volumes and expansion
factors the BHNEP will generate
approximately 132,000 cy of rock, 2
million cy of parent material and 1.3
million cy of silt. These quantities
represent one consideration used in
developing potential disposal options. As
discussed in Section 3.2 and summarized
on Table 3-5, sediment quality must also
be taken into account in considering
disposal sites. Environmental impacts of
using undeveloped sites for disposal,
presented in Section 3.3, are also a factor
in developing disposal options, particularly
related to contaminated dredged material.
Finally, practicability considerations of
costs, technology and logistics which are
reasonably related to project needs must be
factored into the development of disposal
options.
These four factors: sediment quality,
environmental impact, volume and
practicability, were used to formulate
several disposal options by combining
land-based and aquatic sites. The
following sections describe options in four
categories developed through the process
defined above. Each option assumes that
dredged parent material and rock will be
used for beneficial uses to the maximum
extent possible and that these uses will be
identified and expanded throughout the
EIR/S process. The remaining quantity of
this material after beneficial uses are
accomplished will be disposed at the
MBDS.
Options for disposal of silt material
considered potentially unsuitable for
unconfmed ocean disposal (Table 3-13) are
the primary focus of the next section. Op-
tions defined as group "A" include
combining land-based sites for silt
disposal. The "B" group options focus on
combining aquatic sites while "C" group
options include combinations of land-based
sites and aquatic options. The "D" group
options consider aquatic sites previously
used for offshore disposal and which have
the capacity to receive all the project
material.
Tables 3-14 through 3-19 and 3-21 provide
the costs of alternative disposal options
described in the following paragraphs.
The objective of preparing these tables was
to determine relative unit costs by
estimating the total cost to dredge the silts,
process the dredged material, transport the
material to the disposal site, construct any
required features at the disposal site and
any other costs associated with the
dredging and disposal of silts. The costs
are based on April 1995 price levels.
The unit costs should not be used to
estimate a project cost. Project costs, once
a disposal site is selected, will be
computed based on optimal use of
equipment, distribution of silts to other
disposal sites if applicable, and other
factors that can not be estimated until a
final disposal plan is selected and the cost
of disposal of the parent material is deter-
mined. Also cost for mobilization would
have to be added as well as associated
design and construction management costs
required for the selected plan.
Assumptions used are listed on each table.
Existing information was used when
available. Experience from other projects
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was used when specific site data was
unavailable. These assumptions should be
carefully reviewed since, hi some cases,
significant cost items are not included
(i.e., real estate acquisition costs for
upland and shoreline sites).
3.4.1
Options (A")
Use of any of the upland sites for silt
disposal would require that the material be
dewatered prior to disposal. Dewatering
would occur at Boston Harbor shoreline
sites to facilitate trucking efficiency and
nummize potential chloride impacts to
freshwater systems. For calculations of
disposal needs it was assumed that
dewatering and compaction would reduce
the silt volume nearly to its in-situ estimate
of approximately 1.1 million cy.
Option Al. Option Al would involve
disposal of all silt at landfills. The three
landfills which survived the screening
process (see Table 3-1) are expected to
have a combined maximum need of 1,000
cy/day of cover material. TCLP results
indicated that most of the harbor silts
would have to be mixed with equal
quantities of clean materials to be suitable
for daily cover, reducing the total potential
daily use of project material to 500 cy/day,
or 7-13% of the anticipated dredging rate.
Over the anticipated 100 days of silt
dredging (assuming two dredges, yielding
8,000 cy/day each), the total daily cover
needs at the landfills of 50,000 cy would
fell far short of project disposal needs. In
order for landfills to provide the necessary
capacity, project sediments would have to
be buried, not simply used as daily cover.
Using all three landfills, a total of 525
cy/day of silt material, or 52,500 cy over
the 100 day dredging period could be
buried. The maximum disposal capacity
for project silts combining daily cover and
burial is, therefore, 102,500 cy.
As pointed out in preceding sections, there
are definite environmental advantages to
using landfills since they are engineered
and permitted designated disposal areas.
The major drawbacks to using landfills are
daily limitations on quantities that the
landfills can handle and competing public
uses for landfill capacity. It would take
more than 4 years to accommodate the 1.1
million cy generated by the BHNIP using
Option Al. Costs would range from $62 -
$108/cy to dispose of material at the
landfills not including the cost of land
needed to stockpile silt for four years (see
Table 3-14).
Option A2. Option A2 would involve a
combination of one or more landfills and
one or more inland sites. Meeting the
capacity requirements of the BHNIP
would, at a minimum, involve using Wren-
tham (W-495), Squantum Point (QUI-03),
and all three landfills. To reduce the
volume of dredged materials to be buried
at the landfills .(52,500 cy), a third upland
site, Everett (EVR-04), would have to be
included. Any other combination of inland
and landfill sites would fail to provide
adequate capacity. Distribution of dredged
material to four or five different locations
would be difficult logistically and each
town would feel the maximum potential
effects of disposal. In addition, all
dredged material would have to be
dewatered. Once dewatering started,
dredged materials would have to be
removed at the rate of 4,000-8,000 cy/day
(200-400 truckloads) while silt was being
dredged.
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This option also assumes that a lined
disposal facility would need to be designed
and constructed at two or more inland or
coastal sites and that silt overburden in
excess of landfill capacity would have to
be stored until access to sufficient
quantities of clay become available for the
facility's liner. Costs for Option A2
would be approximately $63/cy (see Table
3-15).
Option A3. Option A3 would rely entirely
on developing land-based disposal sites for
the silty material. Individually none of the
four upland sites could provide the total
capacity needed for the BHNIP, but the
combination of the Wrentham (W-495),
Woburn (WOB-11) and Squantum Point
(QUI-03) sites meet the capacity needs.
This option also provides some excess
capacity beyond the current project needs.
The benefits of Option A3 include
reserving landfills for other public uses,
minimizing the area and time needed for
stockpiling and minimizing impact to the
marine environment. Significant
drawbacks include long-term management
of three sites along with attendant costs,
the minor capacity available for future
dredging projects and on-site and
neighborhood impacts from constructing
the facilities and transporting up to 55,000
truckloads of silt to me sites. Costs for
implementation of the above scenario of
the Wrentham, Woburn and Squantum
sites would be $60/cy (see Table 3-15).
3.4.2 Aquatic Options (B)
Aquatic options must be able to
accommodate an estimated 1.3 million cy
silt material which includes the 20%
expansion factor over in-situ volumes.
Option Bl. Option Bl relies on placing all
the silt material in shoreline containment
areas. Use of all the sites short-listed
could not provide all the disposal capacity
needed for the BHNIP, but use of some or
all of the sites could provide a variety of
disposal configurations in combination with
other types of sites. Filling these sites
(Amstar, Cabot Paint, Mystic Piers,
Revere Sugar to fastiand; Little Mystic
Channel to -3 ft MLW; and Reserved
Channel to MHW in its western end and -6
ft MLW near the Summer St. bridge)
would result in a temporary or permanent
loss of marine habitat. However, this
option would benefit the Boston Harbor
aquatic environment by covering the silty
sediments that presently exist at these sites,
would enhance sediment quality for benthic
organisms and could enhance primary
productivity by creation of low salt marsh
in Reserved Channel or subtidal
productivity in parts of the Little Mystic
Channel. Impacts to harbor traffic are also
minimized by providing disposal within the
vicinity of the proposed dredging. This
option would not have capacity remaining
for future use unless an additional site
were included in the development plans.
Costs for maximum capacity at all six sites
range from $7 - $362 cy depending upon
the amount of engineering and site
preparation required (Table 3-16). Costs
include construction of a bulkhead across
the face of each site and transfer of
sediments from barge to truck by crane.
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Option B2. Option B2 involves filling
existing outer harbor subaqueous sites. No
site by itself would provide the capacity
necessary for the BHNE?. Combination of
the maximum fill scenarios at Subaqueous
B and Subaqueous E and Winthrop Harbor
would provide sufficient project capacity.
Because development of the subaqueous
sites would not include construction of a
physical containment structure, future use
(if any capacity remained) would be depen-
dent on having sufficient capping material.
This option would result in temporary
water quality impacts, and loss of marine
subtidal habitat during the disposal and
capping process. The habitat would be
altered in depth, microtopography, and
potentially, sediment grain size
characteristics. The logistical benefits to
this option are substantial as it would mean
disposal sites would be near the dredge
sites, minimizing conflicts with ship traffic
and greatly reducing transportation costs
and impacts.
Costs for this option would be
approximately $20 per cubic yard (see
Table 3-17). No site preparation costs
would be incurred.
Option B3. Option B3 would require
overdredging in at least three navigational
channel areas, creating cells beneath the
authorized channel, filling the dredged
cells with silt and capping it with sand.
Because this scenario would be confined to
the footprint of the federal portion of the
BHNIP, no additional habitat would be
impacted. This option would prolong the
dredging process by 3-6 months and
require temporary barge storage of
dredged silt until the initial cell was
dredged. The three channel areas where it
would be feasible to overdredge, Mystic,
Chelsea and Inner Confluence, would be
able to provide the capacity needed for
BHNIP. Parent material would have to be
disposed elsewhere '(probably MBDS) or
put to some beneficial use. Overdredging
would be impractical in the Reserved
Channel because it is the only tributary of
Boston Harbor that has no physical
restrictions to future deepening. The
ability to localize any impacts makes this
an attractive option for the BHNIP, it
would also offer a potential solution to
hold aside capacity for future maintenance
dredging. Again, transportation distur-
bances and costs would be minimized by
this option.
This option would cost approximately $30
per cy (see Table 3-18).
Option B4. Option B4 would require
dredging and capping a borrow pit for
containment of BHNIP silts. A beneficial
use would be sought for the material
dredged from the pit. Meisburger 7 could
provide capacity for all the silt dredged
during the BHNIP. Meisburger 2 also has
the capacity if the sand and gravel deposits
are proved to average more than 10 feet
thick. The Spectacle Island CAD with a
45-acre footprint could also provide the
necessary capacity. Each of these sites
could be constructed to provide capacity
for other projects if they occur during the
time frame of the BHNIP. The Meis-
burger sites could provide sufficient
additional capacity for future maintenance
dredging of Boston Harbor, assuming
disposal was confined to discrete cells.
Impacts associated with this option would
be temporary but would include
disturbance to areas utilized by commercial
fish and fishing activities. In-harbor sites
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may experience some water quality
exceedences while the offshore sites would
not. Costs would range between $21 and
$33 per cy, depending on the site selected
(see Table 3-19). Reuse of sediment
dredged at the disposal site could reduce
the costs.
Option B5. Option B5 assumes a
combination of aquatic shoreline sites and
any of the other aquatic sites. This option
would require use of at least two sites - an
aquatic shoreline site and a subaqueous, in-
channel or borrow pit site. An advantage
over Option Bl would be the avoidance or
minimization of permanent habitat loss,
depending on the aquatic shoreline site
selected. For example, this option could
provide the capacity needed for the BHNIP
by filling Revere Sugar to fastland and
constructing an intermediate footprint at
the Spectacle Island CAD. Any aquatic
shoreline site could similarly be combined
with the Spectacle Island CAD or with
reduced disposal scenarios at the
Meisburger sites to meet project capacity
needs. Other possible combinations within
this option would require the use of four
or more sites (e.g. Little Mystic Channel,
Subaqueous E, Inner Confluence In-
Channel and Mystic River In-channel).
Any sites not used could potentially be
available for future disposal of Boston
Harbor dredged materials.
3.4.3 Land-Based Aquatic
Combinations (Q
Option Cl. Option Cl would utilize a
combination of landfills and aquatic
shoreline sites. The combination of all six
shoreline sites (to full capacity) and three
landfills. (50,000 cy of daily cover plus
burial of 52,500 cy) would provide
disposal capacity for a total of 1.18 million
cubic yards. This option does not provide
any future maintenance disposal and is
logistically quite complex in terms of
requiring dewatering locations, barge and
truck loading at various sites around the
dredging location and increased truck
traffic in shoreline and landfill commu-
nities. In addition the option removes
landfill capacity from other public users.
The costs for this option range from $37 to
$362/cy depending upon the site.
Option C2. Option C2 would combine
non-landfill upland and aquatic shoreline
sites. It could be implemented by using as
few as three sites; a combination of
Wrentham (W495) and Everett (EVR-04)
with Reserved Channel or Little Mystic
Channel (to -6 ft MLW). That option
would yield excess capacity. Alternative-
ly, Squantum Point (QUI-03), Wrentham,
and Mystic Piers (at maximum capacities)
would meet needs but provide very little
excess capacity. The costs for these
scenarios would range between $30 and
$76/cy depending on the site selected.
Not using Wrentham would require a mini-
mum of eight sites: Squantum Point,
Everett and the six aquatic shoreline sites
except Little Mystic Channel, to their
maximum capacities. Truck traffic
impacts would be reduced in this scenario
but construction of shoreline facilities
would keep the cost range high, between
$37 and $362 depending on the site.
Option C3. Option C3 would utilize a
combination of landfills and aquatic
disposal sites. Use of any of the borrow
pits to full capacity would make landfill
disposal essentially superfluous; however,
landfills could be used in part if there were
3-25
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strong public pressure for landfill use.
Without the landfills, this option becomes
similar to Options B4 or B5, discussed
earlier. The Spectacle Island CAD, Meis-
burger 2 or Meisburger 7 (borrow pits)
could provide the 1.3 million cy capacity
and would be the simplest way to minimize
use of landfill space and completely
confine the dredged materials. No habitat
would be permanently lost although
capping the aquatic site would likely result
in some alteration of substrate character.
Spectacle Island CAD is located in shallow
enough water to enable use of control
structures to isolate the site during
disposal. At other sites, because no
physical structure other than lateral con-
straints provided by bathymetric conditions
(existing or created) would be in place
during disposal, some emigration of
sediments and contaminants might occur
from the aquatic disposal site during place-
ment, potentially affecting nearby fisheries
and other aquatic resources. If borrow
pits were not used for this option, a
minimum of two subaqueous depressions
would be required.
Since no structures would be needed, costs
for disposal under Option C3 would be
less than Cl or C2. Assuming use of
Spectacle Island CAD and East
Bridgewater landfill, Option C3 costs
range from $21 to $62/cy.
Option C4. Option C4 would combine
development of a new land-based disposal
facility with a non-shoreline aquatic site.
Many possible combinations of two or
three sites could meet current needs and
potentially provide excess capacity for
future dredging. Most efficient
implementation of this option would likely
focus on aquatic disposal first;
development of the upland facility would
start when clay dredged from the improve-
ment portion of the BHNIP could be
provided for the liner of the upland
facility. The selection of both the upland
and aquatic sites would determine whether
excess capacity would remain for future
dredged material disposal. Presumably,
any excess capacity would be provided at
the upland site, provoking the question of
costs and responsibility for long-term
management of the facility. Possible
combinations of sites include Wrentham
(W-495) and Subaqueous E; Wrentham,
Everett (EVR-04), and Mystic River; and
Squantum Point (QUI-03), Woburn (WOB-
11), Subaqueous E, Mystic River and
Inner Confluence.
Providing a constructed facility with
substantial excess capacity would drive the
costs of the BHNIP up substantially and
would render this option impracticable. A
regional use facility could be constructed
and maintained by a separate authority.
Costs for the suggested combinations of
sites would range from $19 to $76 per cy,
assuming that upland site preparation costs
would be offset by future users of the
excess capacity provided.
3.4.4 Previously Used Aquatic Disposal
Sites
Option Dl. Option Dl would rely on
solidification of silty sediments prior to
disposal at either MBDS or Boston
Lightship. Solidification processes have
been demonstrated to stabilize metals,
PAHs and PCBs (Breslin, et al. 1988;
IWT Co. 1993, pers. comm.) and have
been considered to provide permanent
removal of these contaminants from the
ecosystem when applied in the terrestrial
environment (see Section 3.5 and Table 3-
20). There would be no short-term water
3-26
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quality impacts associated with offshore
options, as demonstrated by the
ADDAM'S model results. This option
would also address concerns about
resuspension and/or transport of silt
sediments offsite, as well as further
reducing on-site risks. However, this
option would require special handling of
the dredged material, and this, along with
the cost of the treatment material, would
make this option more costly. Disposal of
solidified material at an offshore site could
increase habitat complexity or make habitat
reestablishment more difficult.
Costs for solidification with offshore
disposal would be approximately $90 per
cy (see Table 3-20).
Option D2. Option D2 would rely on
disposal of the silty sediments at either
MBDS or Boston Lightship and subsequent
capping with parent material (primarily
clay) from the channel deepening. As
discussed in prior sections, resuspension of
contaminants during disposal and from the
boundaries of the designated disposal site
has been the major concern associated with
the capping option. However, modeling
done hi this study and by the EPA indi-
cates that short-term water quality criteria
exceedences should not be a problem with
these sites. This project overcomes a
major stumbling block faced in the past by
proposals for capping at MBDS: avail-
ability (or lack thereof) of suitable capping
material. The BHNIP will produce over 2
million cy of parent material, 1.5 times the
quantity of silt to be dredged. Further,
due to the physical constraints created by
the transportation tunnels under the Main
Ship Channel, it is likely that the Inner
Confluence, Mystic Channel and Chelsea
Channel will never be deepened below the
authorized 40 feet. Thus, the supply of
potential capping material is unlikely to be
available for this purpose again without
relying on an outside source. However, hi
its final site designation, EPA has found
that disposal-and-capping (of unsuitable
material) is prohibited at MBDS until its
efficacy can be effectively demonstrated
(40 CFR 228.12 as amended).
Cost for this option would be
approximately $13 to $27 per cy for
disposal of project silt (see Table 3-21).
3.5 ALTERNATIVE
TECHNOLOGY ASSESSMENT
The silt portion of material to be dredged
from Boston Harbor could undergo certain
treatment processes that may either
immobilize or reduce chemical
concentrations to a level that may be
acceptable for open water or other disposal
options. Various commercial treatment
processes exist that have been successfully
utilized elsewhere in the country on
sediment and on other material that may be
applicable to dredged material. In
response to interest generated by the
DEIR/S in potential treatment
technologies, the project team developed a
questionnaire survey of technology
providers. Section 3.5.1 details the
development and results of this survey.
3.5.1 Treatment Technologies
To gather information on technologies
available for the treatment of the
contaminated dredged materials, the
DOWG developed a survey questionnaire.
The survey questionnaire was sent to 38
providers of treatment/disposal services.
The format of the survey was based upon a
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rating system developed by the USEPA for
screening treatment options for Superftmd
sites. This rating method was also used by
the Corps and the EPA in the evaluation of
treatment and disposal options for the
remediation of contaminated sediment in
the Great Lakes (Averett et al. 1990.). To
evaluate the different treatment
technologies, information on the
effectiveness, implementability and cost
was requested. In addition, the respondent
was requested to rank ten factors, from 1
to 10, which affected the estimated cost.
A letter was also sent with the survey form
to provide background information on the
proposed project and to provide a
summary of laboratory results on the
physical and chemical characteristics of the
dredged materials. A copy of the survey
questionnaire is included as Appendix D in
Volume 3 of the FEIR/S.
Of the 38 survey questionnaires sent, 14
were completed and returned (37 percent
response rate). The companies contacted
are listed in Table 3-22. The technologies
represented by the responding firms
included: thermal treatment (7), solvent
extraction (2), soil washing (1),
biotreatment (1), solidification/stabilization
(2), and landfill (1). The questionnaire
responses were summarized and are
presented in Table 3-23. Of the 14
responses, 13 were further evaluated. The
response from Soil Technology was not
considered for additional evaluation due to
limited development of the technology
(laboratory scale).
The following paragraphs summarize each
technology category its potential applica-
bility to the BHNIP.
1. Thermal. This category includes
incineration processes, pyrolytic processes,
vitrification processes, wet air oxidation,
and other processes that involve heating
the sediment hundreds or thousands of
degrees above the ambient temperature. A
number of these processes have been
widely demonstrated, and are considered
effective for destroying organic contami-
nants. However, they are often more
expensive than other options. For ex-
ample, the low fuel value and high water
content of sediments results in high
additional energy input requirements
during incineration. In addition, volatil-
ized metals and other incineration by-
products must be removed from flue gases,
ash or other residues for treatment and
disposal. Incineration processes may also
be difficult to implement because of siting
problems related to complex permitting
requirements and generally poor
community acceptance. On the other
hand, few of the non-incineration thermal
processes have been demonstrated on other
than a bench-scale or pilot basis.
2. Solvent Extraction, Soil Washing and
Other Chemical Treatments. These
technologies use chemical agents and
processes to destroy, modify, remove
(extract) or chemically immobilize toxic
materials, or to alter them in a way that
affects their solubility, stability, separabili-
ty and other properties affecting handling
and disposal. Averett et al. (1990)
identifies available chemical treatment
processes, including chelation and
nucleophilic substitution (dechlorination),
as well as 22 extraction technologies, most
of which can be viewed as essentially
chemical in nature. Variations of these
technologies are potentially effective in
treating PCBs, non-halogenated semi-
volatiles such as PAHs, and metals.
However, according to the literature, many
chemical processes may be difficult to
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implement because of materials handling
and process control requirements that have
not been fully demonstrated for application
to dredged material. Heterogeneity of
grain size and density can limit the effec-
tiveness of the extraction processes. For
those processes, there may also be
problems associated with recovery and
disposal of the extraction solvents.
3. Biotreatment. These technologies,
which include such processes as aerobic
and anaerobic bioreclamation and
digestion, treat contaminated sediment
through the biodegrading action of
microorganisms or enzymes produced by
microbes. However, biodegradation is
effective only to materials high in organic
content, and is generally ineffective for
treatment of heavy metals. In addition,
biodegradation generally works best under
operating conditions which permit a high
degree of control of critical process
parameters such as temperature, moisture,
and nutrient content. These conditions
may not be readily achievable for a large
volume of material where climatic
conditions vary widely or in instances
when the treated materials are highly
heterogeneous. Furthermore, biodegra-
dation processes are complicated by the
possible toxic effects of one contaminant in
the treated matrix on the microorganisms
used to treat another contaminant.
4. Solidification/Stabilization. These
technologies typically isolate and limit
mobility of contaminants through
solidification and/or stabilization (S/S), and
are usually applied to sediments that are
ultimately placed in a confined site or
disposal area. Averett et al. (1990) cite 12
such processes, including lime-based and
Portland cement-based solidification
processes, as well as encapsulation. S/S
facilitates materials handling, decreases the
surface area of the sediment mass across
which contaminant loss or transfer can
occur, and can limit contaminant solubility
through Ph adjustment or sorption
phenomena. According to the literature,
S/S processes can be effective for both
organics and metals. The most common of
these technologies have been demonstrated
on a pilot or full-scale basis for treatment
of soils and solid residues from other
treatment processes. In addition, the
immobilization processes are generally not
as sensitive to process control conditions
as the biological and chemical-extractive
processes. However, the effectiveness of
cement-based solidification processes may
be impeded by organics in the treated
materials which reduce the binding
capacity of the fixative, resulting in prema-
ture structural degradation. Another
limiting factor in the use of immobilization
technologies is the availability of a suitable
confined disposal area or beneficial use for
the solidified material. Marine
applications may be available, however.
Artificial reefs constructed of stabilized
incinerator residues have been placed in
Long Island Sound. Studies on mobility
from these reefs of dioxins and furans
(Wente and Roethal 1993) and various
metals (Breshlin, et al. 1988) have
indicated that these constituents have
neither leached nor been accumulated by
organisms attached to the reef. Other
proprietary stabilizing agents have been
demonstrated to immobilize PCBs and
PAHs (IWT 1993, pers. comm.). Blocks
constructed of solidified dredged material
may also be useful for shoreline protection
and reinforcement.
5. Physical, Mechanical and Landfill
Disposal. These are largely dewatering
and separation technologies often used to
3-29
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prepare materials for additional treatment
or landfill disposal. Dewatering processes
include passive settling and drainage
systems, as well as active mechanical
systems such as belt filter presses and cen-
trifugation. Mechanical separation and
particle classification processes employ
equipment such as grizzlies, hydroclones,
and hydraulic classifiers to separate fine-
grained clays and organic matter from
coarser dredged material. This process
may be-desirable for the Boston Harbor
material not only to facilitate handling, but
because contaminants tend to sorb
primarily onto the finer-grained material,
thereby reducing the volume of material
which would require treatment. These me-
chanical technologies are generally widely
available, and many have been fully
demonstrated in the treatment of sludges as
well as in mining and other materials-han-
dling industries. Factors limiting the
effectiveness of these technologies can
include the moisture content, flow rates,
particle size distribution of the subject
materials, and practicability of handling
the large volumes and high daily produc-
tion (dredging) rates. In addition, debris
typically found in the harbor would have
to be carefully removed prior to process-
ing.
Many of the specific processes which fall
within each of the technology categories
identified above have been reviewed in
published literature, either generically or
in connection with specific dredging or
sediment remediation projects. From this
review it was apparent that different
investigators have used varying approaches
to process nomenclature and categorization
of specific processes (e.g., some reviewers
classify chelation as a chemical process,
others as a physical process; some place
extraction within the chemical treatment
category, others regard extractive
processes as a treatment category by
itself.) Averett et. al. (1990) have
organized over 70 treatment process
options within six technology categories.
It is important to note that while many of
these technologies have been widely
demonstrated in non-marine applications,
only a few have been used for bench scale
and pilot scale tests on marine dredged
materials, and few are considered
commercially demonstrated and available
for this purpose. The total volume of
material being handled on this project and
its rate of production are also serious
impediments to the use of these
technologies.
3.5.2 Technology Screening Criteria
A wide range of treatment technologies
from the above described processes have
been assessed with respect to effectiveness
in treating the specific parameters of
interest in the BHNIP (PCBs, PAHs,
metals) as well as the implementability of
each process considering the volume and
through-put expected from the project.
The critical characteristics of the Boston
Harbor Dredging Project that impact the
selection of the alternative technologies
include the following:
• The types of contaminants that
are of concern, based upon
contaminant con-
centrations found during the
sampling and testing program,
are polychlorinated biphenyls
(PCBs), polynuclear aromatic
hydrocarbons (PAHs), petroleum
hydrocarbons and trace metals.
The ability of each technology to
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treat these contaminants in the
medium of dredged material is an
important qualifier on effective-
ness.
• Approximately 1.3 million cubic
yards of dredged material may be
unsuitable for unconfmed ocean
disposal and therefore could
require treatment. Depending on
the disposal option selected,
production rates could range from
4,000 to 9,000 cy per day. This
quantity and rate of dredged
material would require a large
scale facility for any of the
applicable treatment technologies
to be used. It is therefore,
important to select demonstrated
technologies that have operated
on similar types of dredged
materials at the scale required by
the project schedule. This
imposes a substantial constraint
because there is very limited
experience with operating
treatment technologies at the
scale of the proposed project for
marine dredged materials.
• Implementation of any alternative
treatment technology will result
hi residue streams to the
environment. The ability of each
technology to control these
residue streams, and thus to
mitigate environmental impacts,
is another important consideration
for effectiveness.
Appendix D in Volume 3 contains a copy
of the technology questionnaire that was
sent to the selected treatment providers.
This questionnaire was reviewed and
commented on by the DOWG and contains
the technology screening criteria deemed
important by the group. The results of the
questionnaire are described in the next
section.
3.5.3 Treatment Technology Rating
The treatment technology and disposal
options were rated based upon their stated
effectiveness, implementability and
estimated cost (Table 3-24). For this
study, effectiveness is defined as the ability
of a process to meet the desired
remediation goals while minimizing
impacts to human health and the
environment during the construction and
implementation of the process and the
overall reliability of the process. The
relative rating criteria used a numerical
scale of 1 to 4 with the following
effectiveness ratings (Averett et al. 1990):
Rating = 4. Process option can
achieve the performance objective
with greater than 99 percent
efficiency. The process is highly
reliable.
Rating = 3. Process option can
achieve the performance objective
with 70 to 99 percent efficiency.
This process is moderately reliable.
Rating = 2. Process option can
achieve the performance objective
within 40 to 70 percent efficiency.
This process is minimally reliable.
Rating = 1. Process option is less
than 40 percent efficient in
achieving performance objectives.
The process is not reliable.
3-31
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Since both inorganic and organic
contaminants have been detected in harbor
sediments, the effectiveness of the process
was rated for each contaminant group, for
a maximum combined rating of eight.
The second factor evaluated was
implementability, which is defined as the
technical and administrative feasibility of
using a treatment or disposal technology
option. The implementability ratings are
defined as follows (Averett et al 1990):
Rating = 4. The process option is
commercially available, has proven
applicability to the contaminated
sediments and has been field
demonstrated at process rates similar
to those proposed.
Rating = 3. The process option is
commercially available, has proven
applicability to contaminated
sediments and has been
demonstrated on a pilot scale for
sediments. .
Rating = 2. The process option has
been demonstrated on a bench scale
to be applicable to contaminated
sediment and adequate information
is available to proceed to a pilot-
scale demonstration. Innovative
technologies developed in laboratory
studies may be assigned this rating.
Rating = 1. The process option is
conceptual or emerging and requires
additional developmental work for
application to contaminated
sediment.
The last factor to be evaluated and rated
was estimated cost. The ratings for
estimated costs are as follows (Averett et
al 1990):
Rating = 4. Unit cost for the
process option is less than $20 per
cubic yard.
Rating = 3. Unit cost for the
process option is in the range of $20
to $100 per cubic yard.
Rating = 2. Unit cost for the
process is between $100 and $200
per cubic yard.
Rating = 1. Unit cost for the
process option is greater than $200
per cubic yard.
The individual rating scores for
effectiveness, implementability and costs
were added together to determine the
composite score. Since the effectiveness
of the processes on both inorganic and
organic contaminants were rated
separately, the maximum score for
effectiveness is ,8 and the maximum total
score achievable is 16.
The composite .scores ranged from 7 to 13
(Table 3-24). The lowest composite score
was for the LADS System process. The
LADS System combined thermal
solidification/stabilization process had a
low composite score because it is an
emerging technology, has a high estimated
unit cost (>$100/cy) and because no
information was provided on this method's
effectiveness on organic contaminants.
Commercial Recycling and Laidlaw Waste
Systems received the highest ratings of the
group. The Commercial Recycling
solidification/stabilization process provides
high effectiveness hi treating both organic
3-32
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and inorganic contaminants, relative ease
of implementation and relatively low cost
($55 to $95/ton). Disposal of the dredged
material in the Laidlaw landfill also
received a high rating because of its
effectiveness, relative ease of
implementation and low cost ($50 to
$65/ton). Although this option is highly
rated, its implementation may be
compromised by the volume of material
mat can be disposed of on a daily basis at
the landfill, and the concentration at which
some of the contaminants in the dredged
sediments have been detected. The landfill
would be able to accept up to 2,500 tons
of material per day. The material would
be accepted as long as the concentration of
regulated contaminants (particularly PCBs
and lead) did not exceed state standards.
These ratings of the different treatment and
disposal options is based solely upon the
information provided by the companies
which completed and returned their survey
questionnaires. Based on these responses,
none of the technologies demonstrated
experience in treating marine dredged
sediments or any data which seems
translatable to the BHNIP. If treatment of
dredged materials is required as part of
any future maintenance dredging, the
development of a pilot test program for the
highest rated technologies should be
considered to collect additional information
on the effectiveness, implementability and
cost of using technology.
3.6 BENEFICIAL USES
There is a strong potential for a portion of
the Boston Harbor dredged material to be
used for one or more beneficial uses. The
types and volumes of parent material may
never be available again from Boston
Harbor and therefore provide some unique
mitigation
opportunities for dealing with the silt. The
parent material, specifically the rock and
Boston Blue Clay could have a variety of
beneficial uses.
It is also possible that the silt portion of
the dredged material containing elevated
levels of organics (PCBs, PAHs and petro-
leum hydrocarbons) and heavy metals
could be utilized for daily cover at
Massachusetts Category A lined landfills.
However, the concentration of certain
contaminants in the material must meet the
DEP criteria for this type of use. One
drawback to utilization of the dredged
material for landfill cover is that each
landfill is limited to receiving small
quantities (50-250 cubic yards at the short-
listed sites) of material for daily cover use.
Stockpiling at landfills is limited due to the
confined space available. Consequently,
only a small portion of the Full Project
quantity of dredged silt material (approx-
imately 1.1 million cubic yards total) could
be used in this manner.
Beneficial uses for rock and parent
material are broader in scope and could
include the uses described in the following
paragraphs.
3.6.1 Use of Rock Material
A limiting factor to the beneficial use of
any of the rock material is that some or all
of the rock may be used to armor the in-
channel disposal sites to prevent prop wash
of deep draft vessels from affecting cap
stability. The following are potential uses
of rock remaining from the project after
construction and project uses.
3-33
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A. Fish Habitat Enhancement
There will be a large quantity (< 132,000
cubic yards) of rock removed from this
project which could be utilized for
constructing or improving a fishery
habitat. For a perspective on the overall
volume of material available, a
containment structure with an approximate
height of 15 feet and encompassing an area
of over 5 acres could be constructed. A
structure of this magnitude could be
located in an in-harbor or offshore area
considered to be in need of hard-substrate
to enhance fisheries habitat but away from
heavily utilized locations and high energy
areas. A drawback to the rock to be
removed for the BHNDP is that it will be
mostly small in size (< 10") and mixed
with some clay which would not provide
large interstitial space for fisheries habitat.
It would however, provide hard substrate
for benthic organisms and some interstitial
space which could increase the diversity
and productivity of habitat niches.
B. Shoreline Protection
Some of the rock material could be utilized
for shoreline protection along certain areas
in and around Boston Harbor. Specifical-
ly, there are waterfront areas in Chelsea
and Mystic Rivers and along the Main
Ship Channel that may be structurally
unstable due to erosion from inadequate
protection. As an example, an area that
may benefit from increased shoreline
protection is a city property located along
the south shore of the Chelsea Creek near
Condor Street. Additionally, there may be
shoreline areas outside of Boston Harbor
proper that could benefit from increased
protection. Massport does not have any
waterfront areas that could readily use the
rock material for protection. However,
due to the size of the rock material after
blasting (10" diameter) its use as shoreline
protection will be limited.
C. Containment Site
Development/Armoring
The rock removed from dredging could be
useful for developing a containment site
for the unconsolidated (silty) dredged
material. One such use could be for the
construction of subaqueous berms that
could assist in retaining the finer material
during disposal operations at some types of
sites. Likely sites for this use would
include the subaqueous sites in the outer
harbor and Spectacle Island CAD. The
rock could particularly be useful in
providing armor aggregate for a portion of
the containment berms. However, it is
expected that a substantial quantity of other
larger size rock may be needed to
completely protect the exposed faces of the
containment berms.
j
As stated earlier, some quantity of the rock
may be used to armor the in-channel
disposal areas in the areas that may subject
to the highest prop wash effects (Inner
Confluence). The final quantity expected
to be used for armoring will be determined
during the final design of this disposal
option.
D. Upland Fill /Commercial Reuse
The dredged rock mixed with clay could
be useful for various upland filling
applications where clean fill is needed
(highway construction, etc.). It would be
relatively easy to handle and transport, and
could provide a suitable foundation for
3-34
-------
certain light commercial or industrial uses.
Additionally, the rock could have some
commercial reuse potential as construction
aggregate. Its clay content may decrease
its utility.
3.6.2 Use of Parent Material
A. Qpen Water Disposal Cap
There will be approximately 2 million
cubic yards of parent material (primarily
clay and sand/gravel) available from the
Boston Harbor Dredging Project. The
clay fraction is highly cohesive and could
be useful as capping material at an open
water disposal site. Capping would be
initiated soon after the disposal of silt
material was completed. The operation
would be conducted using traditional barge
scows with bottom operating doors. The
material would be point dumped within
specific radii from the center of the silt
material to form a continuous mound
deposit of approximately 1 meter thick on
top of the silt. This would effectively
provide a clay cap which would seal off
the silt from the environment.
However, since the open water options
have been dropped from further
consideration as disposal sites for this
phase of the project, based on DEIR/S
comments, there will be no opportunity to
demonstrate capping with the parent
material.
B. Nearshore Containment Cap
The parent material could also be used in a
similar fashion for capping any of the
nearshore containment. However, because
of limited barge access to some of these
sites, it may be necessary to utilize land-
based equipment or a barge mounted crane
for offloading the sediments from barges
for cap placement.
C. Subtidal/Intertidal Habitat Creation
The Reserved Channel and Little Mystic
Channel containment options will require
surface material that would be suitable for
establishment of subtidal and intertidal
habitat. The parent material to be dredged
would be suitable as base material that
could be placed directly onto the silty
dredged material in the containment site.
A surface layer of clean sand/silt mixture
placed over the clay would provide
substrate favorable for benthic recruitment
and establishment of vegetation.
D. Landfill Liner/Cap/Closure Material
The parent material could also be useful
for lining landfills or other upland sites
that may require liner material. Since the
parent material is primarily clay, it is
highly impermeable and could be suitable
for this purpose. This material could also
be useful for capping or covering some of
the silt to be dredged from this project that
may require burial. The predominately
clay parent material may also be useful as
final closure material at certain landfills.
Massachusetts DEP, Division of Solid
Waste Management has identified a state-
wide need of 7 million cubic yards of clay
for municipal landfill capping and a need
for at least an equal amount of fill for
landfill grading prior to capping.
The Central Artery/ Third Harbor Tunnel
project has been working with the DEP hi
developing a clay distribution program to
3-35
-------
meet part of this need. TheCA/Thas
identified some 82 communities in
Massachusetts that could use a portion of
the day coming from the CA/T project.
Appendix H in Volume 3 of this FEIR/S
contains the application form and
requirements for communities to receive
clay from the CA/T project.
The Corps is willing to investigate ways of
working with the DEP to further this
program. However, a limiting factor on
the Corps is that the project's parent
material is considered improvement
material and therefore, its dredging and
disposal must consider the least costly
option to meet the 1988 Feasibility Study
cost-effectiveness evaluation. The parent
material is suitable for unconfined ocean
disposal at the MBDS, which is also the
least costly option. Beneficial use of the
parent material cannot increase the cost of
its disposal above that of using the MBDS.
However, to advance the interests of the
DEP, the project team evaluated means of
making the parent material available for
use at municipal landfills if there is still a
need and interest after CA/T project
benefits are realized.
Trucking and transporting project clay
would be cost prohibitive. However, the
project team investigated barge access
facilities within the Commonwealth that
could serve as distribution points for
project parent material. Assuming that a
15-foot minimum depth would be required
for a barge, the project team identified
several ports and the unlined municipal
landfills that could be served from them
(see Table 3-25). Should these
communities express an interest in
receiving project clay, individual
arrangements may be made with the Corps
to barge a specific quantity of clay to a
designated site for off-loading, handling,
transporting and stockpiling at the
municipalities expense.
Based on the contaminant profile and
physical characteristics of the parent
material, the material would be suitable for
liner material, intermediate cover, a
subgrade layer, or a final cap. . Should a
municipality demonstrate an interest in this
material, further testing will be required to
ascertain the suitability of the material
under DEP Policy #BWP-94-037 and Solid
Waste Management regulations. The
project team will continue to coordinate
interests in the beneficial re-use of the clay
with the DEP.
3.6.3 Summary of Beneficial Uses
In summary, beneficial uses of rock and
parent material may include a variety of
enhancement and containment purposes as
follows:
ROCK (Amount available: approximately
132,000 cubic yards)
Fish habitat enhancement
Shoreline protection
Containment site develop-
ment/armoring
Upland fill
Commercial reuse (construction
aggregate)
PARENT MATERIAL (Amount
available: approximately 3.3 million cubic
yards)
Open water disposal cap
Nearshore containment site cap
Landfill liner/cap
Landfill final closure material
Other upland site liner/cap
3-36
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3.7 PREFERRED DISPOSAL OPTION
The preceding discussions have dem-
onstrated the complexity of identifying and
combining sites to form disposal options.
This section will assess the issues involved
in critically evaluating the merits of the
disposal options to select the preferred
option.
Selection of the Preferred Disposal
Alternative will be based on screening the
options through a series of key criteria
which include:
• ability of disposal sites/methods to
meet regulatory criteria for
receiving material
• minimization of negative .
environmental impacts
• maximization of environmental
benefits
• reasonable capacity for this project
• reasonable in light of logistics,
technology and cost.
Environmental impact is the most
important criterion. Land-based (landfill
and development of new inland or coastal
sites) and aquatic (nearshore and various
open water alternatives) disposal sites
would inherently involve different types of
impacts (Table 3-7) since different
resource types would be involved in each
case. Thus, while comparisons among
land-based alternatives and among aquatic
alternatives are fairly straight forward,
comparisons between upland and aquatic
alternatives are more complex. The types
of environmental impacts that would weigh
most heavily against a site being included
in the preferred alternative (based on
sensitive resources identified in this study)
would include unmitigatable risks to:
• marine and/or upland
habitat
• wetlands
• anadromous fish passage
• important resident fish and
shellfish
• water quality
• threatened and endangered
species
• traffic (marine and/or
roadway)
• neighborhood impacts
Distinctions can be made among disposal
alternatives based on their ability to
provide environmental benefits (Table 3-
9), although, again, it is difficult to weigh
benefits against each other, particularly on
the generic level. However, benefits that
would weigh most heavily toward includ-
ing a particular alternative would include:
• maximizing use of parent
material
• use of any available sand
or gravel
• providing capacity for
future dredging needs
• providing clean bottom
habitat within Boston
Harbor
• providing alternatives
which are practicable and
achievable
Identifiable future disposal estimates (i.e.,
50-year maintenance for Boston Harbor)
point out the necessity to evaluate disposal
options on both the generic and specific
levels. As indicated in Section 3.4,
identifying capacity for the BHNEP is the
3-37
-------
first challenge. Adding future dredging
projections to the equation makes the
evaluation more complex but is critical to
the process and was identified as such in
the MEPA scope. The preferred disposal
option should include a site or sites and
methods to accommodate future dredging
as well as the current need.
Cost, in addition to logistics and
technology, is a factor hi determining
practicability of the disposal options.
Final cost comparisons among disposal
options cannot be made without
considering specific sites. An acceptable
benefit/cost ratio must be reached in order
to qualify for Federal participation in a
navigation improvement project. The
three major costs used to compute the
benefit/cost ratio include: design, dredging
and disposal costs incurred to deepen the
Federal Channels (parent material); design,
dredging and disposal costs incurred to
deepen those berths that receive direct
project benefits (silt and parent material);
and costs associated with maintenance of
the improvement project for its economic
life (50 years). Costs to dredge and
dispose of silt (maintenance material) from
the Federal channel during initial
construction of the improvement project is
not included as part of the improvement
project cost as this is considered
maintenance of the existing channels. The
total improvement cost must be compared
to the benefits that the deeper project will
provide. Therefore, the benefit-to-cost
ratio for the project or each separable
increment of the project must be at least
1:1 for the project to qualify for Federal
funding.
While a particular disposal option may
pass the Federal participation criteria, the
sponsor may find its cost contribution
unacceptably high. There is no cost
criterion that applies to the project related
berths, however, affordability relative to
the perceived benefits in site management
would likely be used by individual owners
in their decision to participate.
Identification of suitable disposal options
for BHNIP has been an open process
involving valuable collaboration with the
project's working groups. The DEIR/S
was another step in that process.
Table 3-26 provides a summary of the
principal impacts associated with the
twenty-four disposal sites and one
treatment technology that remained poten-
tially suitable for BHNIP material disposal
after site screening. The existing
conditions at each site and principal
environmental impacts associated with its
use are provided in Attachment 1 in
Volume 1 of this FEIR/S.
The next chapter provides a detailed
environmental analysis of the sites
described in Attachment 1 and listed on
Table 3-1 as having survived the site
screening process. The Chapter also
includes a practicability screening applying
cost, technology and logistics, culminating
in a selection and description of the
preferred alternative. That alternative is
in-channel disposal with sand capping.
The In-Channel disposal scenario assumes
that the silt material will be dredged from
each channel and placed on a barge, while
deeper cells will then be dug in the Mystic
River, Chelsea Creek and Inner
Confluence channels (parent material); the
silt would then be placed within the cells
and capped with sand. Parent material
removed from the trench would be
disposed at MBDS. Each
3-38
-------
channel/tributary would then contain its
own capped silt material. The environ-
mental resources impacted for this disposal
alternative are the same as for the dredging
site.
Benefits from this alternative include
keeping the silt material within the channel
to be dredged, thus reducing the amount of
silt exposed to biological resources
elsewhere and keeping transportation costs,
vessel traffic disturbances and socio-
economic impact to a minimum.
The proposed disposal sites occur in
tributaries currently used by ship traffic.
The U.S. Coast Guard would need to
coordinate between ships needing to use
the tributary and disposal activities.
However, since material would essentially
be disposed at or near the same place it is
dredged, only barges for temporary
storage and those required to dispose of
excess parent material would have to be
dealt with; major barge movement within
the Harbor should not be necessary.
The characteristics of the underlying
sediments in the channels have been
described in Section 2.2 of the DEIR/S as
clean parent material. Bulk sediment
analysis indicated that no parameter
exceeded Category I limits. The channel
would be filled with silt and capped with
sand. The remaining parent material
would be disposed at the MBDS or other
suitable site. Since the channels are
currently covered with silt material, .
returning the silt to its place of origin and
capping it with sand would provide an
environmental benefit.
The disposal site would end up, as
proposed, 3.0 to 5.0 feet deeper than the
channel's current authorized depth. The
area would of course remain subtidal; the
substrate would change from a silt material
to sand with gravel or rock armoring in
areas affected by prop wash. The benthic
community may change as a result of this
sediment change but should be "healthier"
because the availability of contaminants for
bioaccumulation will be reduced, at least
until future siltation occurs. No federally
or state-listed threatened or endangered
species are expected to be at risk from this
activity in the channel and tributaries.
Each of the channels falls within the
Designated Port Areas of Boston Harbor
(e.g., Mystic River, Chelsea Creek, East
Boston and South Boston designations)
under State jurisdiction (310 CMR 10.00)
and within Tidal Water jurisdiction under
Section 404 of the Federal Clean Water
Act. Since these proposed disposal sites
are part of the overall maintenance
dredging operation, their construction will
not impact these regulated resources
beyond the impacts of the dredging itself,
other than from increased silt plumes
during disposal. ADDAM's model results
indicate that these plumes should not
directly impact economically important fish
and shellfish resources. Any impacts
would be temporary and, upon capping
and project completion, the resources
should restore themselves to natural
conditions. Newly-exposed substrate and
clean capping materials will provide better
substrate conditions for benthic community
development in the near-term.
3-39
-------
-------
Boston Harbor Dredging Project EIR/S
©
Sco/e.- Q 10
Approx. Scale in Miles
Figure 3-1
Locations of potential disposal sites
extensively evaluated.
Source:
USGS Quadrangles
Revised by NAI to reflect pertinent site conditions.
,4V
-------
TABLE 3-1. POTENTIAL DISPOSAL SITE LISTS BY CATEGORY PRODUCED
AT THE END Of EACH SCREENING PHASE.
PHASE 1
LAND-BASED OPTIONS:
Land-based Inland
BRN-06
CAN-17
EBROOK
HLB-13
NAT- 02
NOR-02
RAYNHAM
RED-03
SAG-02
W-495
WEY-13
WIL-06
WIL-07
WOB-11
Land-based Coastal
BOS -13
BOS-23
BOS-25
BOS-31
EVR-04
LOGAN
LYN-02
MAL-01
CHAR-01
PROV
QUI-03
QUI-09
PHASE 2
BRN-06
HLB-13
NAT- 02
NOR-02
RED-03
SAG-02
BOS-13
BOS-23
BOS-31
LYN-02
CHAR-01
QUI-09
PHASE 3
(DEIR/S)
¥-495
WOB-11
EVR-04
QUI-03
(Continued)
-------
TABLE 3-1. (CONTINUED)
PHASE 1
PHASE 2
PHASE 3
(DEIR/S)
Landfills
Agawam
E. Bridgewater
Fall River
Plainville
Fitchburg/Westminister
AQUATIC OPTIONS;
Aquatic Shoreline Sites
Arnstar1
Cabot Paint
CHEL-01
FPC
me
Mystic Piers
Northend Park
ResChn
Revere Sugar
Spec CDF
Subaqueous Depressions
Subaq B
Subaq D
Subaq E
Subaq F
CHEL-02
Winthrop
E. Bridgewater
Fall River
Plainville
Fitchburg/-
Westminister
GCR Peabody*
Amstar
Cabot Paint
CHEL-01
FPC
LMC
Mystic Piers
Northend Park
ResChn
Revere Sugar
Spec CDF
Hangman's Island*
Island End River*
Subaq B
Subaq E
CHEL-02
E. Bridgewater
Plainville
Fitchburg/-
Westminister
Amstar
Cabot Paint
LMC
Mystic Piers
ResChn
Revere Sugar
Sub B
Subaq E
Winthrop
(Continued)
-------
TABLE 3-1. (CONTINUED)
PHASE 1
PHASE 2
PHASE 3
(DEIR/S)
Borrow Pits
Willet I
Willet III
Meis 2
Meis 7
Tn-Ghannel Sites
Willet I
Willet III
Spec Is CAD
Existing Disposal Sites
MBDS
Boston Lightship
MBDS
Boston Lightship
Meis 2
Meis 7
Spec Is CAD
Chelsea Creek**
Mystic River**
Inner Confluence**
MBDS
Boston Lightship
*Added after DOWG meeting, 1/25/93
**Added after DOWG meeting, 4/15/93
-------
TABLE 3-2. ADDITIONAL INFORMATION COLLECTED FOR NEARSHORE AQUATIC, IN-CHANNEL, BORROW PITS, SUBAQUEOUS AREAS AND
EXISTING DISPOSAL SITES (OCTOBER 1994)
SITE
Nearshorc Aquatic
Mystic Piers
Revere Sugar
Ainstar
Cabot Paint
Little Mystic Channel
Reserved Channel
In-Channel/Borrow Pits
In-Channel Mystic River
Ill-Channel Chelsea Creek
In-Channel Inner Confluence
Spectacle Island
Meisburger 2 & 7
Subaqueous
Subaqueous B
Subaqueous E
Winthrop Harbor
Disposal Sites
Boston Light Ship
BENTHOS
SPI1
X
X
X
X
X
X
X
X
X
X
X
X
X
BENTHOS
X
X
X
X
X
X
X
X
X
X
X
X
X
X
FISHERIES:
PELAGIC2
X
X
X
X
X
FISHERIES:
DEMERSAL3
X
X
X
X
X
LOBSTER
TRAPS
X
X
X
X
X
X
X
X
X
X
1 Sediment Profile Camera
2 Gillnets
3,
Otter Trawl
-------
iPABiS 3-3. CHXRKCTXKISTICa OT CEMtRIC DlltOlfilt
to
-£•
£
oaRACzraisric
FotenUaJ
Env-tronmentaJ
ProMems
Major TsstJngr
JieguJrements
Callable Options
'
Design
Considerations
Available Control
Measures
LIKED txmntii
(CATEGORY A)
• Leachate Impacts
• (Minimal since
lined)
• Balk analysis
• TCLP*
• Elutriate
• Dally cover
• Disposal with burial
• Existing site design
• Transportation
• Mix with cleaner
materials
• Dewaterlng
PJMIKBD JMWriM
(cxumwt s)
• Leachate Impacts
• Bulk analysis
• TCLP
• Elutriate
• Unconflned disposal
• contouring/grading
material
• Dally cover
• Existing site design
• Transportation
• Diking
• Runoff control
• Deuaterlng
UOID-BMSD
(Now-twmraiy
• GrounoVa ter
contamination
• Watland Jmpacts
• Bulk analysis
• TCLP
• Elutriate
• Unconflned disposal
• Confined disposal
• Reuse
• Capacity
• Containment
• Monitoring
• Transportation
• Diking
• Runoff control
• Leachate control
• Dewatering
AQOTriC 5HOKBMKE
COmMKHSNT
• Contaminant
migration
• Burial Infracts
• Bulk analysis
• TCLP
• Elutriate
• Habitat creation
• Upland use
Capacl ty
Containment
Monitoring
Transportation
Bulkheading
Diking
Subaqueous jberm
Capping
OPE1I FKTZR
Water coJumn Jnpacts
Banthlc Impacts
Bloaccumulatlon
Bulk analysis
Benthlc toxlclty
Bloaccumlatlon
• Unconflned disposal
• Capping
Capacl ty
Containment
Monitoring
Transportation
Point dumping
Capping
opflif-KATZR mm
CONMINWOT
• Contaminant
migration
• Burial Impacts
• Bulk analysis
• Elutriate or water
quality modelling
• Benthlc Impacts
' Bloaccumulatlon
• Habitat enhancement
• Burial
Capacl ty
Containment
Moni tor Ing
Transportation
Subaqueous berm
Borrow pit
Capping
Point damping
"TCLP - toxic concentrations leaching potential
-------
TABLE 3-4. MASSACHUSETTS BEOOIATOH* OtttDElINE XB»u OF OHED01D NATERIMS TOR VWU00S DISPOSAL AMERHAT1VES.
tr-
r
BULK ANALYSIS (jjjfl)
Mercury , O.5
lend <100
Zinc <2oo
Arsenic <10
Cadmium <5
Chromium <)oo
Copper ,200
Nickel 1 5
100-200 >200
20MOO >400
10-20 >20
5-10 >1Q
10O300 >300
2OMOO . >400
50-100 >1QQ
<5 5-10 >10
<40 4CWO >eo
<60 6O90 >90
<0.5 05-1.0 >1.0
LANOffU CATEGORY
(UNEO) (UNUNEO)
10
500
40
25
SOO
2
100
10
UPLAND DISPOSAL
MW. BULK SOL CONC.'
FOR TCLP ANALYSIS (ppm)
2
500
40
14
100
2
100
4
TCLP REGULATORY
LEVELS' (mg/i)
1000 500
100
too
100
20
5
1
5
5
0.2
1
5
dhm
^ dredged nwterW wtifch «xc««(k any M the KmXt may be mixed vvWickmir material to bring the material Into
•«TClPanalyele would batwedod (or thoMpanxndwa tlut exceed any Wed thrathokt '"8"u"raM™llmo
« material has non-haz»rdou» crwracterMcs If Kited resuWoty levtl* are not exceeded using the TCLP test methotfa
open water disposal
for evaluating open water disposal
— wtlhthlscliutflcatlon
-------
ruin 3-5. tnuaiie* or naoauttt er tottai KIRKM mvzauio* aatw/mmie nonce exDomrri n* nuuooi DIIHJUL unxKutni.
, V}
J^
-C.
-o
ram* in*
P.eaervad Channel FP
conloy P
Awiy Base P
Boston Edison IBarge f
Berth;
Boston Edison P
tlntakel
Main Ship Channel Tf
North Jetty T
Mystic Piers P
Chelsea River FP
Kastein Minerals P
-------
TABLE 3-6. SUMMARY OF POTENTIAL SIZE PREPARATION, MANAGEMENT
REQUIREMENTS FOR USE OF GENERIC DISPOSAL
ALTERNATIVES.
SITE PREPARATION
•Baseline investigations
•Permitting
•Acquisition
•Dredging
•Containment structure-dike
,-jberm
-bulkhead
•Access road/rail
•Alteration of navigational channel
•Liner
MATERIAL PREPARATION
•Dewstering
•Mixing
TRANSPORTATION
•Barge
•Truck
•Rail
SITE MANAGEMENT
•Runoff control
•Closure
-landscaping
-dredged clay
-soil
-structure
-marine organic
-marine mineral
-prior demonstration of success
-marine habitat
•Burial
•Daily Cover
VBUQSD
OSBFILL
X
•X
X
X
X
X
X
X •
X
vpxano
Z2O8HD
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
UPLXSD
coaszai
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
aga
HEaSSHBRS
X
X
X
X
X
X
X
X
X
X
X
BORROW
sxss
X
X
X
X
X
X
X
azze
OBBS
JE&XER
X
X
X
X
X
X
X
EXXSTHKS
DISPOSZZ
SITES
X
X
X
X
X
-------
TABLE 3-7. POTENTIAL IMPACTS TOOM SILT DISPOSAL AT OSN1RIC ALTERNATIVE DISPOSAL SITES.
IMPACT
Exceeds Sediment Criteria
Loss of Habitat
Terrestrial
Katland (F.W.)
Marine subtldal
Marina Intertldal
Alteration of Habitat
Terrestrial
Matland (F.W.)
Marine subtidal
Marine Intertldal
Mater Quality
Freshwater
Marine
Current Use (Displacement)
socloeconomlc
Traffic
Truck
Barge
Historic/
Rrcheologlcal
Emigration Potential for
Contaminants
During disposal
Prior to containment
Volatizatlon
Long-term
Bloaccum. potential
MOID-BASED
LKUDFILl IWWIffi) COASTAL
X
X
X
P
X
X
P
P
X
X
X
P
P
P
X
P
T
X
P
T
X
y
X
X
X
P
P
P
AQUATIC
TOTAL PARTIAL
X
X
X
X
T
X
X
P
T
X
P
T
X
X '
P
P
SUBAQUEOUS
OUTER HARBOR CWMtEl
T
X
T
X
P
P
P
P
T
T
X
T
X
P
P
P
P
T
BORROW PITS
M/ CAP
T
T
T
P
P
P
P
P
T
EXISTING sires
W CAP W/O CAP
T
T
T
P
P
P
P
T
X
T
T
T
P
P
X
X
SOLIDIFICATION
T
P
00
Key: X - Impact; P - Possible impact; T - Temporary Impact.
-------
TABLE 3-8. IMPACTS CAUSED BY USING SPECIFIC UPLAND SITES FOR BOSTON HARBOR DREDGED MATERIAL DISPOSAL.
O^
\
(J\
e>
RESOURCE
SITE DESIGN
WATER QUALITY
MARINE
INTERTIDAL
MARINE
SUBTIDAL
SHELLFISH
FINFISH
FRESHWATER
AQUATIC
RESOURCES
WETLAND
VEGETATION,
WILDLIFE
THREATENED &
ENDANGERED
SPECIES
HISTORIC &
ARCHEOLOGICAL
SOCIOECONOMIC
& LANDUSE
TRAFFIC
PLAINVIEW/ EAST
LAIDLAW WESTMINSTER BRIDGEWATER
LANDFILL LANDFILL LANDFILL
•Dewatering facility at Mystic Pier or North Jetty -Dewalerlng facility at Mystic Pier or North Jetty •Dewaterlng facility at Mystic Pier or North Jetty
•No special site modifications required -No special site modifications required -No special site modifications required
•Available capacity: dally cover < 500 cy/day 'Available capacity: dally cover < 250 cy/day 'Available capacity: dally cover < 400 cy/day
•Waste s 1 50-200 cy/day -Waste < 200 cy/day -Waste < 75 cy/day
None
WRENTHAM
•Dewaterlng facility at Mystic Pier or North Jetty
•Site modification from undeveloped
forest/shrub to lined landfill
•Footprint approx. 60 acres
•Capacity approx. 785,500 cy
•No groundwater Impacts
•Possible temporary surface water Impacts
from sedimentation and contaminants
Nona
None
None
None
None
None
None
•Permanent loss of 9 ac. wetland
•Permanent loss of habitat to resident
species and fragmentation of wooded land
Possible habitat for northern halrstreak
and Philadelphia panic grass
None
No change In land use, but use for dredge
material disposal would preempt other uses
Increase In truck traffic for transporting
dredged material to landfill
Possible change from undeveloped forest
and shrubland to lined containment facility
•Increase In truck traffic during
construction and dredge disposal phase
•Heavy truck use already occurs from
adjacent gravel operation
-------
TABLE 3-8(CONTINUED). IMPACTS CAUSED BY USING SPECIFIC UPLAND SITES FOR BOSTON HARBOR DREDGED MATERIAL DISPOSAL
RESOURCE
SITE DESIGN
WATER QUALITY
MARINE
INTERTIDAL
MARINE
SUBTIDAL
SHELLFISH
FINFISH
FRESHWATER
AQUATIC
RESOURCES
WETLAND
VEGETATION,
WILDLIFE
THREATENED &
ENDANGERED
SPECIES
HISTORIC &
ARCHEOLOGICAL
SOCIOECONOMIC
& LANDUSE
TRAFFIC
WOBURN
•CX»waierir»g f«»ty it Myrfc Plflf or North J«ty
•Copping docod municipal landllll
wdhUnedfAcltty
• Footprlnt-25oao5
• Capadty-158,600cy
•May Improve oroumfwater quality by
capping landil
•Possible temporary surface water Impacts
from sedimentation and contaminants
None
None
None
None
Possible temporary Impacts to tributary
to Hall's Brook
•Permanent loss of portion of 1 ac. wetland
•Permanent loss of early successlonal Held
and wooded habitat
None
None
Permanent capping of closed municipal landllll
•Construction traffic
•Increase In truck and rail traffic due to
transport of dredged material to landllll
EVERETT
•Dredge bams (we
•Site modlllod from abandoned
urban land to iMdllll
• Footprint's acres
• Cnpadly-70,000 cy
SQUANTUM
POINT
•Cowtnxs Kmtd coolnlnmont borm and
II wWi dredged materials up lo 10 fott deep
•Downier through detention basin, cap when dry
• Footprint-IB acre* • CapncHy-210.000 cy
•Temporary local Increase In sutpanded solids during dredging
•Temporary release of contaminants during dredging
•Dredging ol 2 acres of Intertldal habllat
•Potential slllallon during dredging and barge manuovertng
Dredging ol approximately 0.03 ac. of line-grained
sediment and disturbance during barge manueverlng
will result In temporary loss of benlhlc production
No harvestable shellllsh beds In area
Temporary disturbance to flnflsh habllat.
Permanent loss of approximately 0.3 ac. ol
fine-grained tidal Hat and 0.03 ac. ol salt marsh
Alteration ol approximately 1.4 ac. of
lino-grained habllat
Temporary Impact to mussel and softshell dam habitat
Temporary disturbance lo flnflsh habllat.
None
•No freshwater wetland Impacts
•Loss of open land In an urban setting
None
Jacknlle drawbridge within 1000 ft ol site
Permanent change from abandoned urban land to landllll
•Construction traffic
•Dredged material transported by barge
•Permanent loss of approximately 0.33 ac. of wetland
•Permanent loss ol shrubland bird habllat and
disturbance of salt marsh tidal flat habitat
Loss ol short-eared owl migratory/wintering habitat
None
None
•Construction traffic
•Dredged material transported by barge
-------
TABLE 3-9. POTENTIAL BENEFITS OF DREDQBD MATERIAL DISPOSAL ALTERNATIVES.
BENEFIT
Remove/Isolate Contaminated
Sediment from Environment
Cover Existing Contaminated
Sediments
Enhance Resource/Habitat
Economic Benefits
Cap Existing Disposal Site
Beneficial Use of Parent
Material
Use of Existing On-site
Materials
Future Use of Impacted Area
UPLAND
LANDFILL INLAND COASTAL
XXX
P
P P
X
X XX
X P P
AQUATIC
SHORELINE
TOTAL PARTIAL
X X
X X
X
P
X X
X X
SUBAQUEOUS
OUTER HARBOR CHANNEL
X X
X X
X
BORROW
PITS
W/ CAP
X
P
X
X
EXISTING DISPOSAL
SITES
W/ CAP W/O CAP
X
P
P
X X
X
X X
SOLIDIFICATION
X
X
•«;
P
VxJ
Key: X = Benefit; P = Possible benefit
-------
TABLE 3-10. IMPACTS CAUSED BY USING SPECIFIC AQUATIC SHORELINE SITES FOR BOSTON HARBOR DREDGED MATERIAL DISPOSAL.
RESOURCE
SITE DESIGN
WATER QUALITY
MARINE
INTERTIDAL
MARINE
SUBTIDAL
SHELLFISH
FINFISH
FRESHWATER
AQUATIC
RESOURCES
WETLAND
VEGETATION,
WILDLIFE
THREATENED &
ENDANGERED
SPECIES
HISTORIC &
ARCHEOLOGICAL
SOCIOECONOMIC
& LANDUSE
TRAFFIC
MYSTIC PIERS
TOTAL FILL
BulHiud hubw fiot; III bthtnd
•IKcufl.WwiIf loMHW Of Hjhir..
Dr»gUrt» to pojMon t§*n»nl».
Foolpilnt-2.7to.;
cipicKy. 167,000 cu. ydt.
•Ptmwmnt loss ol as ml Eon gal.
of Boston Hmbor capacity, no
Impact on currant velocity
•D»wtt«rlng controls modid.
Permarwnl loss ol macroalgae,
bamaclo, and blua mussel
production on hard substrate
Loss ol 2.7 acres llne-gralnod
soft habitat
PARTIAL FILL
BuRhMd hwbof («cr,fflb«htal
iMourtiWwilrtoOttMLW.oip
vrlth ttnd to MIW. Dingin* (o
potWon tedlrwrt*. Footprint"
2.7«o,;o»ptoXyrf8^00ou,ydt..
•Pimwuvtrt low ol 29 mMon o»I.
of Boston Harbor capacity, no
Impact on currant vitodty
•Dowatorlng controls nsedod
No low ol hard substrate
•Alteration ol 2.7 ac. fine-grained
soft substrate,
•Capping of existing contaminants
•Loss of piling and bulkhead
(hard substrate)
Loss ol Interlldal mussels on pilings
•Mortality of demersal fish eggs;
larvae and adults
trapped behind bulkhead.
-Permanent loss of llnllsh refuge
and foraging habitat
•Mortality of demersaal fish eggs;
larvae and adults
trapped behind bulkhead.
•Temporary loss of llnllsh refuge
and foraging habitat
REVERE SUGAR
TOTAL FILL
Btiikhiftd hiitof f io«; 13! btWnd
il«cix1«Wwi!rtoMHWcxMgtm.
Of *C lino to potl'Jon fMRrnMt*.
FootpiM-SJw.;
o«p«clty»204,000 cu ydt.
•PwiMMfll bit o! 21 mMon gi],
of Boston Harbor capacity, no
Impact on current vs'odty
•DtwaKtlng controls nttdtd.
Permanent loss of macroalga®,
barnacle, and IWorlna snail
production on hard substrate
Loss ol 3.7 acres fine-grained
soft habitat
PARTIAL FILL
BuMtttd hitter Uo»; IN bthtnd
tilt eurfiWwiJf to 0 ft MLW, o»p I
wHh wtd to MLW. DrigllM to
pojIBtw) f tdimMti, Footprint*
3.7 no.; c«p»otty -86,000 cu ydt.
•P«rman«nt ION of 27 mIKon giJ.
of Boilon Herbor ctpidty, no
Impact on current viloctly
•Dewaleilng controls nocdod.
No loss ol hard substrate
•Allorallon ol 3.7 ac. fine-grained
soft substrate.
•Capping ol existing contaminants
•Loss ol piling and bulkhead
(hard substrate)
AMSTAR
TOTAL FILL
Bulkbud hirbor f «c»; III bthM
sit ourttlnftwlr to MHW or hlghtr.
Drigltrt* to potWon Mdtmtnlt.
Foolprlnt-3.5 ia;
o«piolty«241 ,000 cu yd*.
•Pjtm«n4nl few ol 53 million gat.
of Boston HarborcapacKy, no
Impact on current velocity
•Dtwaterlng controls nodtd.
•Permanent loss of barnacle,
mussel and green algae
production on hard substrate
•Permanent loss of gravel beach
Loss of 3.5 acres fine-grained
soil habitat
PARTIAL FILL
BiXXhnd hirbor do* (HI bthtnd
ill ourt.Ww.lr to 0 ft MLW, cup
vAh city (o MLW. Diigtlrw to
position s«dlm»nti. Footprint*
3.5 10.; c«p«cSy-128,000 ou.yd*.
•Psimarunt loss ol 39 roMton gal.
ol Boston Harbor capacity, no
Impact on currant volodty
•Dowaloilng controls nitdtd.
No loss ol hard substrate
•Alteration ol 3.6 ac. fins-grained
soft substrate.
•Capping ol existing contaminants
•Loss of piling and bulkhead
(hard substrate)
None
•Mortality ol demersal fish eggs;
larvae and adults
trapped behind bulkhead.
•Permanent loss of llnllsh refuge
and foraging habitat
•Mortality of demersal fish eggs:
larvae and adults
trapped behind bulkhead.
•Temporary loss of flnllsh refuge
and foraging habitat
•Mortality ol demersaal llsh eggs;
larvae and adults
trapped behind bulkhead,
•Permanent loss of llnllsh reluge
and foraging habitat
•Mortality of demersal fish eggs;
larvae and adults
trapped behind bulkhead.
•Temporary loss of llnllsh reluge
and foraging habitat
None
Permanent loss ol 2.7 acres
subtldal wetlands
Possible bird forage habitat
Alteration of substrate of 2.7 acres
subtldal wetlands.
Possible bird forage habitat
Permanent toss of 3.7 acres
subtldal wetlands
Possible bird forage habitat
Alteration o! substrate of 3.7 acre;
subtldal wetlands.
Possible bird forage habitat
Permanent loss of 3.6 acres
subtldal wetlands
Possible bird forage habitat
Alteration of substrate ol 3.5 acres
subtldal wetlands.
Possible bird forage habitat
Nona
None
•Conversion of aquatic habitat
totastland.
•Proposed future use compatible
wild neighborhood.
•Transport sediments by barge
(approx. 100 barge trips)
•No truck traffic Impacts
Eliminate future potential use
In commercial port activity
•Transport sediments by barge
(approx. 70 barge trips)
•No truck traffic Impacts
•Conversion of aquatic habitat
tofaslland.
•Proposed future use compatible
with neighborhood,
•Transport sediments by barge
(approx. 100 barge trips)
•No truck traffic Impacts
Eliminate future potential use
in commercial port activity
•Transport sediments by barge
(approx. 60 barge trips)
•No truck traffic Impacts
•Elimination of MWRA floating
dock on eastern edge ol site.
•Conv. of aquatic hab. to fastland
•Prop, future use of compatible
w/surroundlnq landuse
•Transport sediments by barge
(approx. 130 barge trips)
•No truck traffic Impacts
•Elimination ol MWRA floating
dock on eastern edge of site.
•Restriction of ship to shore
transfer of people and freight
•Transport sediments by barge
(approx. 90 barge trips)
•No truck traffic Impacts
V
-------
TABLE <3-10(CONTINUED). IMPACTS CAUSED BY USING SPECIFIC AQUATIC SHORELINE SITES FOR BOSTON HARBOR DREDGED MATERIAL DISPOSAL.
RESOURCE
SITE DESIGN
WATER QUALITY
MARINE
INTERTIDAL
MARINE
SUBTIDAL
SHELLFISH
FINFISH
FRESHWATER
AQUATIC
RESOURCES
WETLAND
VEGETATION,
WILDLIFE
THREATENED &
ENDANGERED
SPECIES
HISTORIC &
ARCHEOLOGICAL
SOCIOECONOMIC
& LANDUSE
TRAFFIC
CABOT PAINT
TOTAL FILL
Bulkhead harbor (ace; fill behind
sis curtaln/welrto MHW or higher.
:ootprlnto6,6 aoj
oapaolty-lflB.OOOcu.yds.
Permanent loss of 33 million
gallons of Boston Harbor capacity
Oewateilng controls needed.
Perm, loss of Fucus & barnacle
production on hard substrate
Permanent loss of gravel
beaches on northeast and
northwest
Permanent loss of 5.6 acres
me- grained soft habitat
PARTIAL FILL
Bulkhead harbor lace; (III behind
sltt ourtaWwelr to-0 ft MLW, cap
with sand to MLW. Footprint-
5.6 ao.; capactty=18,000 cu. yds.
•Permanent loss of 12 million
gallons of Boston Harbor capacity
•Dewaterlng controls needed.
Permanent loss of gravel
beaches on northeast and
northwest
•Alteration of 5.6 ac. of soft
substrate.
•Improve sediment quality
None
•Mortality of temersaj'flsh'eggs;
!arvae and adults
trapped behind bulkhead.
•Permanent loss of (Irtish refuge
and foraging habitat
Permanent loss of 5.6 acres ol
Intertldal and eubtldal wetlands
•Mortality ol demersal fish eggs;
larvae and adults
trapped behind bulkhead,
•Temporary loss of flntlsh refuge
and foraging habitat
1 ITTI C MVCTIr* fUANIKIPI
LIT 1 Lb MYo 1 IO l/nMNNtL
Bulkhead river (ace; (III behind
silt curtalrvwelr to -3 ft MLW, cap 3 ft
thick with sand to MLW. Footprint-is ao.;
oapadty-303,000cu.yds.
•One CSO and six discharge pipes
may need to be diverted
•Slltatlon controls needed.
•Temporary reduction In Fucus, green algae and
barnacle production on hard substrate
•Short-term Impact on small sandy-gravel beach
•Conversion to shallow subtldal habitat
•Improve sediment quality
•Temporary loss of 1 6.0 acres of soft substrate
Short-term Impacts on mussels and metal bulkhead
RESERVED CHANNEL
AREA A
Bulkhead near Summer St. Bridge,
west of marina. FIIHo -6 ft MLW;
Cap; Cut bulkhead,
Footprlnt«B.Oao
oapactty«14,oy
•Perm, loss of 48.5 million gallons
of Boston Harbor Capacity, no
Impact on current velocity
•Slllatlon controls needed.
Temporary reduction In Fucus,
green algae and barnacle
production on hard substrate
habitat
•Improve sediment quality
•Temporary loss of 8.9 acres of
soft substrate
AREA B (WEST END)
Bulkhead westernmost end;
Fill to 9.6 n MLW, Cap to
MHW; Remove bulkhead; Satlmarsn
Footprlnt«7.7 ao
CapaoRy=1 86,000
of Boston Harbor Capacity
•3 CSCys would need to be relocated
•Slltatton controls needed.
algae and barnacle prod, on hard sub.
•Perm, toss of small rocky beach
-Increase In Intertldal habitat
•increase primary prod, (saltmareh)
habitat, then to salt marsh
•Permanent loss of 7.7 ac. ol
soft substrate
None
WS
•Short-term mortality of fish eggs; larvae and adults trapped behind bulkhead.
•Temporary reduction on prey available to species which feed primarily on benthte Invertebrate
•Temporary loss of llnflsh refuge and foraging habitat
Not applicable
Alteration of 5.6 acres of
Intertldal and subtldal wetlands
Temporary Impact of 15 ao. of subtldal wetlands
Temporary loss of 8.9 ac.
of subtldal wetlands
larvae and adults
trapped behind bulkhead.
•Temporary loss of flnflsh refuge
and foraging habitat
,
Temporary loss of 7.7 ac.
ol Intertldal and subtldal
wetlands
None
Nona
•Conversion ol aquallo habitat
to lastland.
•Transport sediments by barge
(appro*. 70 barge trips)
•No truck traffic Impacts
None
•Transport sediments by barge
(appro*. 15 barge trips)
Nona
•Transport sediments by barge (approx. 170-220 barge trips
or 11,700 -16,200 truck trips)
Possible conflict with yacht club
•Sediment by barges (140) and trucks (9800): minor delays to
commercial/recreational boating traffic.
•Some roadway traffic delays and noise Impacls
-------
TABLE 3-11. POTENTIAL IMPACTS CAUSED BY USING SPECIFIC SUBAQUEOUS, BORROW PIT AND UN-CHANNEL SITES FOR BOSTON HARBOR DREDGED MATERIAL DISPOSAL
RESOURCE
SITE DESIGN
WATER QUALITY
MARINE
INTERTIDAL
MARINE
SUBTIDAL
SHELLFISH
FINFISH
FRESHWATER
AQUATIC
RESOURCES
WETLAND
VEGETATION,
WILDLIFE
THREATENED &
ENDANGERED
SPECIES
HISTORIC &
ARCHEOLOGICAL
SOCIOECONOMIC
& LANDUSE
TRAFFIC
SUBAQUEOUS
B
Pl»ot r««mie«pvrfth*«nd to
Mtf.pthoMEflMLW.
Foo4prlnt»83 ««.
C*p*®Hy«up to 682,000
Polonllal lorwffllorqwjlty oxcoodoncos
alter 4 hra up to 4500 ft from dump sfto.
Pormanonl loss ol up to 204 million
ga). of Boston HarborwalO'r capacity
SUBAQUEOUS
E
Pines till and otp v*h Mod lo°
Mdipthof-SHMlW.
FootprlnWO *orii
C«pac!ty tip to 501,000
•Potential for water quality oxco&dinws
after 4 tins up to 4500 ft Irom dump site.
•Permanent loss of up to 201 million
gal. ol Boston Harbor water capacity
WINTHROP
HARBOR
Pltc* it* wvtJ c«p tttth *»nd to
IfMtdlpthoMZHMLW.
FoolprM'BiGrti
Cipicty»187,000cy
•Potential tor waterqualdy •xceedwiOM
alter 4 hra up to 4500 ft from dump stto
•Parmanenl loss ol up to 64.8 million
gal. of Boalon Harbor water capacity
CHELSEA
CREEK
IN-CHANNEL
•OVK drrig* o>w>il to -65 ft MIW
*FW to 42 ft MIW ttfth conUmintM
wdfmtnt*
^.pto-(OftWLV/v*hf»f>d
•C«p«eKy^32,OOOcy
•Potential forwetw qoaffly oxc«sdoncos
alter 4 hrs up to 4500 ft from dump site
•Negligible effect on current velocity
•No change In Harbor volume
INNER
CONFLUENCE
IN-CHANNEL
•Ov«r dr«
-------
TABLE 3-11 (CONT'D). POTENTIAL IMPACTS CAUSED BY USING SPECIFIC SUBAQUEOUS, BORROW PIT AND IN-CHANNEL SITES FOR BOSTON HARBOR DREDGED MATERIAL DISPOSAL.
RESOURCE
SITE DESIGN
WATER QUALITY
MARINE
INTERTIDAL
MARINE
SUBTIDAL
SHELLFISH
FINFISH
FRESHWATER
AQUATIC
RESOURCES
WETLAND
VEGETATION,
WILDLIFE
THREATENED &
ENDANGERED
SPECIES
HISTORIC &
ARCHEOLOGICAL
SOCIOECONOMIC
& LANDUSE
TRAFFIC
MYSTIC
RIVER
IN-CHANNEL
•Over dredge to -70 ft MLW
•Fill to -44 ft MLW without
•Cop to -42 H MLW with sand
•Capaolty»7421000cy
•Potential for water quality exceedences
after 4 hrs up to 4500 ft from dump site
•No change In Harbor volumes
MEISBURGER
2
•Dredge ptt 13 ft deep
•FIU with dredged sIS
•Cap with clay and sand to pre-existing contours
•Footprlnt°86 acres
•Capactr/«1,320,000cy
Water quality criteria not exceeded
outside site 4 hrs after dump.
MEISBURGER
7
•Dredge ptt 10 ft deep
•Fill with dredged silt
•Cap with clay and sand to pre-existing contours
oFoolprlnt=121 aores
«CapacHy-1,320,OOOoy
Water quality criteria not exceeded
outside site 4 hrs after dump.
SPECTACLE
ISLAND
CAD
•Dredge existing sediments to -31 ft MLW
•FIU with dredged silt
•Cap with clay and sand to pre-existing contours
•Footprlnt»20-S0 acres
•Capaclly-1.320.OOQ ey
Potential for water quality exceedences;
Construction/mitigation steps would be planned
Not applicable
No habitat loss beyond that caused
by Improvement dredging project
Potential short-term Impacts to
nearby resources due to Impacts
to water quality
•Temporary loss of 1 50 ac. of soft substrate
•Beach Improvement from excavated material
•Temporary loss of 82-403 ac. of soft substrate
•Beach Improvement from excavated material
•Short-term Impact on lobster population
•Temporary Interference with commercial fishery
Temporary loss of 20-70 ac. of son substrate
Potential temporary slltallon on nearby
mussel beds
•short-term mortality ol fish eggs, larvae and adults
•Temporary reduction of prey available to species which feed primarily on Invertebrates
•Temporary Interference with commercial fishery
,. ^-
Not applicable
No Impacts beyond those Incurred due
to dredging project
None expected
•No state Jurisdictions! wetlands ( >80ftMLW)
•Temporary Interference with commercial fishery
None expected, although some species of whales
and sea turtles could occur In area Incidentally
Temporary loss of 22 ac. of subtldal wetlands
Not applicable
None
Prolonged dredging In navigational channel
resulting In additional minor Interruption of
shipping traffic
•90 days of additional dredging
•185 barge trips to remove
parent material
Temporary Impact on fishing and recreational boating
•Dredge will be on-slte for > 1 year
•660 barge trips required to remove sediments
•660 barge trips required to transport harbor
sediments to site
•Dredge will be on-slte for > 1 year
•660 barge trips required to remove sediments
•660 barge trips required to transport harbor
sediments to site
•Temporary Impact on recreational boating
•Possible conflict with construction of fish reef
•Dredge will be on-slte for> 3 months
•660 barge trips required to remove sediments
•660 barge trips required to transport harbor
sediments to site
-------
TABLE 3-12. IMPACTS CAUSED BY USING EXISTING OPEN WATER DISPOSAL SITES FOR BOSTON HARBOR DREDGED MATERIAL DISPOSAL
RESOURCE
SITE DESIGN
WATER QUALITY
MARINE
INTERTIDAL
MARINE
SUBTIDAL
SHELLFISH
FINFISH
FRESHWATER
AQUATIC
RESOURCES
WETLAND
VEGETATION,
WILDLIFE
THREATENED &
ENDANGERED
SPECIES
HISTORIC &
ARCHEOLOGICAL
SOCIOECONOMIC
& LANDUSE
TRAFFIC
MASSACHUSETTS BAY DISPOSAL SITE
BOSTON LIGHTSHIP
Corttoou* potnl disposal of * two wwta after ttart of dredging;
Capping with parent material.
No water quality criteria cxcoodoncos alter four hours ouislde the site.
Not applicable
•Benlhte resources maintained In pioneering stage due to regular disposal
•No significant change from existing conditions
Possible mature benthlc community now existing,
Disposal would temporarily convert to a pioneering community.
Gills of any shellfish In Immediate vicinity of disposal site could become clogged
•Some mortality of demersel fish due to burial
•Avoidance of disposal operation
Not applicable
Designated disposal site
Alteration of subtldal habitat conditions
In Tidal Waters
•Endangered whales and turtles are transients In area, and would likely avoid disposal activities
None
•Designated dredged material disposal site
•No change In current use
Needs further review
Former dredged material disposal site
•Disposal of parent material and rack would require up to 500 barge trips (4000 cy capacity)
•Disposal of silt would require up to 1 70 barge trips (4000 cy capacity)
•Average of two barge trips per day
01
-------
TABLE 3-13. ALTERNATIVE DBPSOSAL OPTIONS FOR DISPOSAL OF SILT SEDIMENTS
SITE
TYPE
UPLAND
Landfill
inland
Coastal
AQUATIC
Shoreline
Subaqueous
In-Channel
Borrow Pit
Existing Sites
TREATMENT
SITE
E. Bridgewater
PlainvHIe
Fitchberg/
Westminster
Wobum
Wrentham
Everett
SquantumPL
Amstar
Cabot Paint
Lt Mystic
Channel
Mystic Piers
Reserved A
Reserved B
Revere Sugar
Sub. B
Sub. E
Chelsea
Mystic
Inner Confl.
Meisburger2
MeisburgerT
Spec. Isl. CAD
Boston Lt Ship
MBDS
Solidification
CAPACITY (CY)
200 daily cover, 200 fill in cy/day
50 daily cover, 250 fill in cy/day
75 daily cover, 250 fill in cy/day
158,600
451,200
37,000
210,000
128,000 MLW, 241,000 MHW
18,000 MLW, 198,000 MHW
303,000 to -3 ft MLW
98,000 MLW, 187,000 MHW
14,000 MLW, 390,000 MHW
186,000 MLW, 315,000 MHW
86,000 MLW, 204,000 MHW
562,000
591,000
332,000
742,000
246,000
1,320,000
1,320,000
1,320,000
1,320,000
1,320,000
6,000 per day
COST
$62
$94
$108
$69
$62
$76
$44451
$62-$50
$362-$66
$47
$47-$38
$341 -$44
$45-$40
$93-$61
$20
$19
$30
$30
$30
$30
$33
$21
$16
$27
$55
DISPOSAL OPTION
A1,A2,C1,C3
A1,A2,C1,C3
A1,A2,C1,C3
A2, A3, C2, C4
A2, A3, C2, C4
A2,C2,C4
A2, A3, C2, C4
B1,B5,C1,C2
B1,B5,C1,C2
B1,B5,C1,C2
B1,B5,C1,C2
B1,B5,C1,C2
B1,B5,C1,C2
B1,B5,C1,C2
B2, B5, C3, C4
B2, B5, C3, C4
B3, B5, C3, C4
83, B5, C3, C4
B3, B5, C3, C4
B4, B5, C3, C4
B4, B5, C3, C4
B4,B5,C3,C4
D1.D2
D1.D2
D1
-------
TABLE 3-14. COST ESTIMATES FOR LANDFILL SITES FOR BIIN1P SILT DISPOSAL
Landfills
Location
East Brldgewater
Plalnvllle
Fltchburg/Westmlnste
Distance
(miles)
25
35
r 45
Silt
Volume
(CYI
200,000
200,000
200,000
Dredging
Cost
$8.29
$1,658,000
$1,658,000
$1,658,000
Dewatering
Cost
$17.00
$3,400,000
$3,400,000
$3,400,000
Hauling
CosWCY
$9.20
$12.25
$12.25
Hauling
Cost
$1,840,000
$2,450,000
$2,450,000
Tipping
Fee
K/CYl
$28
$56
$70
Tipping
Cost
$5,600.000
$11,200,000
$14,000,000
Total
Cost
$12,498,000
$18,708,000
$21,503,000
Unit Cost
for Silt
($/CY)
$62.00
$94.00
$108.00
\
th
ASSUMPTIONS
Silt volume Includes disposal and possible contour capping.
Hauling costs assumed fleet of 20 trucks and 3 loaders working 5 days per week.
Dewatering cost based on combined use of air drying and belt filter press and Includes land rental.
-------
TABLE 3-15. COST ESTIMATES FOR LAND-BASED SITES FOR BHNIP SILT DISPOSAL
Wobum-11
Footprint
(SqFt)
Perimeter
{FO
Dike Material
(CY1
Dike Cost
S15.00 /CY
Lining Cost
$26.00 ISf
Road Fill
$13.00 ICY
Clearing/
Drainage
617,500
3,100
63,400
5951,000
$1,783,889
$1,560,000
559,200
Sift
Volume
(CY)
Dredging
Cost
$8L29 /CY
Hauling
Cost
$9.30 /CY
Cap
Cost
S15.00 /CY
Dewatering
Cost
$17.00 /CY
Treatment
Cost
$2.00 /CY
158,600
$1,314,794
$1,474.980
$525,000
$2,696,200
$517,200
Land Cost
Total
Cost
Unit Cost
forSift
$212,638
$10,895,000
ASSUMPTIONS
Footprint (area) planimetered from quad sheet
Footprint selected to avoid wetlands and power Snes. As a result two of trtee areas were not large enough to use.
Dike volume computed from dace height of 12", top width of 101 and side slopes of 1V to 3H ("CAD CELL" program).
SeeTmertWckness10liMth2lcap1hickness.
Liner consists of geomembrane for positive cut-off, T of sand and a geotextte filter.
Ateo included in cost of Sner is a geotexfite filter at the cap layer.
Sand cost $12/CY. geeiextile S3/SY and geomembrane $16/SY.
Volume of road fB caloiated for road within the diked area requiring 120,000 CY.
Clearing costs determined by assuming S28OO/acre for 14 acres.
Drainage cosls assumed to be rerouting local drainage @ $20,000.
HauJng costs assumed fleet of 30 tucks and 4 loaders working 7 daySWcfor 3 worths.
Cap was assumed to be trucked irom Boston (Boston Blue day from Improvement Project).
Dewatering cost based on combined use of air drying and belt filter press and includes landrental.
Treatment of leacnatefrom site is ejected to require saine tainted VK&? tobereansixxted
to a local treatment plant, construction of package treatment plant ortrueWng to the ocean.
Dewaterirs site rental catuated @ $157/SP.
-3-
-------
TABLES-IS (CONTINUED). COST ESTIMATES FOR LAND-BASED SITES FOR DISPOSAL OF BHNIP SILTS
06/15S5
03:40 AM
Footprint
Perimettr
Dike Mite nil
Dike Cost
S11.00 /CY
Lining Coat
525.00
Road Fill
S13.00 /CY
Clearing/
Drainage
6.18S
91,200
51.003,200
$4.404,400
S1.950.000
$188,000
Sit
Votum*
Dmdging
Coct
SS-29 I
Hauling
Cost
S12.00
Cap
Cost
S11.OO
-------
TABLE 3-15 (CONTINUED). COST ESTIMATES FOR LAND-BASED SITES FOR DISPOSAL OF BHNIP SILTS
UPLAND
Squantum - (Trucking)
Footprint
(SqFt)
782,500
Silt
Volume
(CY)
210,000
Dewatering
Cost
$17.00 /CY
33,570,000
Squantum - (Barging)
Footprint
(SqFt)
782,500
Silt
Volume
(CY)
210,000
Dredging
Access
(CY)
Perimeter
(FT)
4,300
21 Cap
Volume
(CY)
46,000
Road Fill
$13.00 /CY
S650.000
Perimeter
(FT)
4,300
reap
Volume
(CY)
46,000
Dredging
Access
$8.50 /CY
Dike Material
(CY)
87,900
Total
Volume
(CY)
256,000
Dike Material
(CY)
87,900
Total
Volume
(CY)
256,000
Rehandling
Cost
$15.00
Dike Cost
$15.00 /CY
$1,318,500
Dredging Cost
9S39 /CYSilt
$7.76 /CY Parent
32,097,860
Land Cost
3269,456
Dike Cost
$15.00 /CY
31,318,500
Dredging Cost
$829 /CYSilt
$7.76 /CY Parent
32,097,860
Total
Cost
Clearing/
Drainage
345,200
Hauling
Cost/CY
$5.00
31,280,000
Total Unit Cost
Cost for Silt
39,231,000 343.96
Clearing/
Drainaqe
$45,200
Land Cost
3269,456
Unit Cost
for Silt
ASSUMPTIONS
160,000
$1,360,000
35,550,000
310,641,000
350.67
Footprint (area) planimetered from quad sheet
Footprint selected to avoid wetland.
Dike volume computed from dike height of 12', top width of 101 and side slopes of 1V to 3H time perimeter of 4300".
Sediment thickness 10 with 2' cap thickness.
Clearing costs determined by assuming S1400/acre for 18 acres.
Drainage costs assumed to be rerouting local drainage @ 320,000.
Hauling costs assumed fleet of 10 trucks and 3 loaders working 7 days/wk for 4.5 months.
Dewatering cost based on combined use of air drying and belt filter press and includes land rental.
Volume of road fill calculated for road within the diked area requiring 50000 CY.
The 2700" x 175' access channel assumed to have existing depth of -4'MLW and require a 12' depth.
Rehandling cost is for a barge-mounted crane to unload all scows.
Dredging costs - parent = 37.76, silt = $8.29.
Dewatering site rental calculated ©S1.57/SF and land cost calculated @ S15,000/Ac.
-------
TABLE 3-15 (CONTINUED). COST ESTIMATES FOR LAND-BASED SITES FOR BHNIP SILT DISPOSAL
Everett-04
Silt
Volume
(CY)
37,000
Dike
(CY)
2' Cap
Volume
(CY)
18,000
Dike
Cost
$15.00 /CY
Total
Volume
(CY)
55,000
Footprint
Area
(SQ FT)
Mechanical Rehandling
Dredging Cost/CY
Cost/CY
$8.29 Silt
$7.76 Parent
Average
Depth
(FT)
$15.00
Wier/Silt
Curtain
Cost
Total
Dredging
Cost
$1,271,410
Total
Cost
Bulkhead Depth of Bulkhead
(LF) Piles Cost
(FT) ($30/SF)
400
Unit Cost
for Silt
($/CY)
105 $1,260,000
17,100 $256,500
243,936
$36,590
$2,824,500
$76.34
ASSUMPTIONS
Footprint (area) planimetered from quad sheet.
Footprint selected to avoid crossing municipal boundary.
Dike volume computed from dike height of 8', top width of 10' and side slopes of 1V to 3H.
Dike length 1700'.
Sediment thickness varies (assumed to be 8') with cap thickness of 2'.
Volumes shown are dredged volumes (expansion of dredged material has not been applied).
Rehanding cost is for a barge-mounted crane to unload the scows.
Bulkhead costs reflect $30/SF for steel.
Bulkhead assumed to tie to fast ground and only be necessary along fronting water edge.
Wier required and is based on cost of $0.15/CY of material contained.
Dredge costs - parent = $7.76, silt = $8.29.
-------
TABLE 3-16. COST ESTIMATES FOR AQUATIC SHORELINE OPTIONS
Volume
Concrete Panel Bulkhead
Revere Sugar
Amstar
Mystic Piers
Cabot Paint
Little Mystic Channel
Reserved Channel A
Reserved Channel B
Fill to
level of:
(MLW)
20
20
20
20
20
20
20
Sediment
Volume
(CY)
204,000
241,000
187,000
198,000
840,000
390,000
315,000
3' Cap
Volume
(CY)
18,000
17,000
13,000
27,000
70,000
43,000
38,000
Total
Volume
(CY)
222,000
258,000
200,000
225,000
910,000
433,000
353,000
Surface
Footprint
(SOFT)
160,000
153,000
120,000
243,000
630,000
390,000
334,000
Dredging/Handling
Revere Sugar
Amstar
Mystic Piers
Cabot Paint
Little Mystic Channel
Reserved Channel A
Reserved Channel B
Dredging
Cost/CY
(silt)
$8.29
$8.29
$8.29
$8.29
$8.29
$8.29
$8.29
Dredging
Cost/CY
(parent)
$7.78
$7.76
$7.78
$7.76
$7.76
$7.76
$7.76
Rehandllng
Cost/CY
$16.00
$15.00
$15.00
$15.00
$15.00
$15.00
$15.00
Total
Dredging
Cost
$5,160,840
$5,999,810
$4,651,110
$5,225,940
$21,156,800
$10,061,780
$8,201,230
Depth
(FT)
37.5
45.5
45
25
39
30
28.5
Tie-Backs
Three Rows
Cost/row
($220/LF)
$1,019,700
$702,900
$128,700
$1,059,300
$237,600
$544,500
$148,500
Capacity/
Ft Depth
(CY)
6,000
6,000
4,000
9,000
23,000
14,000
12,000
Bulkhead
(LF)
1545
1065
195
1605
360
825
225
Depth of
Piles
(FT)
125
125
125
125
125
110
110
Panel
Cost
($4/SQFT)
$339,900
$234,300
$42,900
$353,100
$79,200
$181,500
$49,500
Steel
H-plles
($B5/LF)
$2,051,953
$1,414,453
$258,984
$2,131,641
$478,125
$964,219
$262,969
Geotextlle/Dralnage Quantities
Fabric
(SY)
24,215
22,384
14,308
31,458
71,560
46,083
37,824
Sand Filter
(CY)
11,852
11,333
8,889
18,000
46,667
28,889
24,741
T-dralns
(EA)
77
53
10
80
18
41
11
Oeotextlle/Oralnage Costs
Revere Sugar
Amstar
Mystic Piers
Cabot Paint
Little Mystic Channel
Reserved Channel A
Reserved Channel B
Wler/Sllt
Curtain
Cost
$24,000
$22,950
$18,000
$36,450
$94,500
$58,500
$50,100
Design and
Const. Mgt
Cost
$654.000
$628,000
$376,000
$679,000
$1,628,000 '
$891,000
$655,000
Contingency
Cost
(26%)
$2,499,000
$2,400,000
$1,436,000
$2,595,000
$6,220,000
$3,406,000
$2,504,000
Total
Cost
$12,496,630
$11,998,470
$7,180,879
$12,974,748
$31,100,528
$17,031,862
$12,519,391
Unit Cost
for Silt
($/CY)
$61.26
$49.79
$38.40
$65,53
$37.02
$43.67
$39.74
Fabric
($7/SY)
$169,507
$156,689
$100,158
$220,208
$500,920
$322,583
$264,765
Sand Filter
($13/CY)
$154.074
$147,333
$115,556
$234,000
$606,667
$375,556
$321,630
T -drains
(SB60/EA)
$43,260
$29,820
$5,460
$44,940
$10,080
$23,100
$6,300
B'head Labor
($4/SF)
$380,396
$262,215
$48,011
$395,169
$88,636
$203,124
$55,397
ASSUMPTIONS
Volumes shown are dredged volumes (expansion of dredged material has not been applied).
Surface area planlmetered from navigation chart vertical sides assumed.
Depth Is an average as shown on navigation chart or recent survey.
Dredging cost Is not dependent on distance to disposal site.
Bulkhead assumed to tie to fast ground and may be necessary along several sides.
Wlar required If disposal site to create fast land (cost Is $0.15 x surface area).
Rehandllng Includes floating crane plus repositioning of material In the site.
Bulkhead design source: J. Fowler & NY District MOTB.
T-dralns thru bulkhead every 20' extend Into filter.
Sand filter laid on top of fabric In 2' layer.
Fabric placed on bottom and sides.
Concrete panels fitted between H-plles @ 384 SF/day.
Tie-backs assumed to run length of bulkhead,
Labor costs for divers, crane and laborers @ $1720/day.
-------
TABLE WC. (COWBWED) ESTIMATES FOR AQUATIC SHORELINE OPTIONS TO MLW
Volvo*
ConcrtU P«n«l Bulkht «d
Revere Sugar
Arntlar
Mystic Plora
Cabot Point
Little Mytllo Channel
Reserved Channel A
Reserved Channel B
Ravers Sugar
Amslar
Mystfo Piers
Cabot Paint
Little Mystic Channel
Reserved Channel A
Reserved Channel B
Fill to
iwtlofi
(MLW)
0
0
0
0
-3
•8
9.5
Dredging
Cost/CY
(ill!)
$8.29
$8.29
$8.29
$8.29
$8.29
$8.29
$8.29
Sidlmint
Volum*
(CY)
86,000
128,000
98,000
18,000
303,000
14,000
186,000
Dredging
Coit/CY
(parant)
$7.76
$7.76
$7.76
$7.76
$7.78
$7.76
$7.78
3' Cup
Volumi
(CY)
18,000
17,000
13,000
27,000
70,000
44,000
37,000
Drtdfjlnq/Handllnn
Rehnndllng
Co«t/CY
$15.00
$15.00
$15.00
$15.00
$15.00
$15.00
$15.00
Total
Volum*
(CY)
104,000
145,000
-111,000
45,000
373,000
58,000
223,000
Total
Dredging
Cost
$2,412,620
$3,368,040
$2,576,300
$1,033,740
$8,690,070
$1,327,600
$5,174,080
flttrftCt
Footprint
(flQFT)
160,000
153,000
120,000
243,000
630,000
390,000
334,000
Tie-Backs
True* Rows
Cost/row
(J220/LF)
$1,019,700
$702,900
$128,700
$1,059,300
$237,600
$544,500
$148,500
Dipth
(FT)
17.5
25.0
26
5
16
4
18
Ctpiclty/
FtD«plh
(OY)
6,000
6,000
4,000
9,000
23,000
14,000
12,000
BulkhtBd
(LF)
1045
1065
195
1605
360
825
225
Diptnof
Pitts
(FT)
105
105
105
105
102
84
99.5
OiottxUlt/Dralnag* Quantities
Fabric
(SY)
20,782
20,018
13,875
27,892
70,640
43,700
37,581
3and Filter T-dralns
(CY) (BA)
11,852 77
11,333 53
8,889 10
18,000 80
46,667 18
28,689 41
24,741 11
Bulkhead
(LF)
185
375
225
930
380
585
585
Pintl
Cost
($4«QFT)
$216,300
$149,100
$27,300
$224,700
$46,080
$95,700
$40,090
Bulkhead Cost
Depth of
Piles
(FT)
105
105
105
105
102
84
99.5
,att«t
H-pllts
(J8WLF)
$1,723,841
$1,188,141
$217,547
$1,790.578
$390,150
$736,313
$237,887
Bulkhead
Cost
($30/80 FT)
$519,750
$1,181,260
$708,750
$2,929,500
$1,101,600
$1,474,200
$1,746,225
GaotoxtllefDralnaas Costs
Revere Sugar
Amslar
Mystic Piers
Cabot Paint
Little Mystic Channel
Reserved Channel A
Reserved Channel B
Wler/Sllt
Curtain
Cost
$24,000
$22,950
$18,000
$36,490
$94,500
$58,600
$50,100
Design and
Const. Mgt
Coit
$419,000
$414,000
$225,000
$341,000 .
$741,000
$250,000
$440,000
Contingency
Cost
(25%)
$1,600,000
$1,582,000
$861,000
$1,303,000
$2,831,000
$956,000
$1,682,000
Total
Cost
$8,000,138
$7,911,270
$4,304,540
$6,514,421
$14,153.197
$4,780,170
$8,408,258
Unit Cost
for Silt
($/CY)
$93.02
$61.81
$43.92
$361.91
$48.71
$341.44
$45.21
Fabric Sand Fitter
($7/8Y) (S13/CY)
$145,474 $164,074
$140,123 $147,333
$97,125 $115,556
$195,242 $234,000
$494,480 $606,667
$305,900 $375,556
$26^,928 $321,630
T-dralns
<$S80/EA)
$43,260
$29,820
$5,460
$44,940
$10,080
$23,100
$6,300
B'head Labor
($4/SF)
$242,070
$166,864
$30,553
$251,471
$51,570
$107,102
$44,822
ASSUMPTIONS
Volumes shown are dredged volumes (expansion of dredged material has not been applied).
Surface area planlmetered from navigation chart vertical sides assumed.
Depth Is an average as shown on navigation chart or recent survey.
Dredging cost Is not dependent on distance to disposal site.
Bulkhead assumed to tie to fast ground and may be necessary along several sides.
Wter required If disposal sHe to create fast land (cost Is $0.15 x surface area).
Rehandling Includes floating crane plus repositioning of material In the site.
Bulkhead design source: J, Fowler & NY District MOTB.
T-dralns thru bulkhead every 20' extend Into filter.
Sand filter laid on top of fabric In 2' layer.
Fabric placed on bottom and skies.
Concrete panels fitted between H-pltes @ 384 SF/day.
H-plles spaced 8' apart.
Tie-backs assumed to run length of bulkhead.
Labor costs for divers, crane and laborers © $1720/day.
-------
TABLE 3-17. COST ESTIMATE FOR SUBAQUEOUS DEPRESSION OPTION FOR BHNIP SILT DISPOSAL
Subaqueous B
Footprint Perimeter
(SqFt) (FT)
Lenglh»>
Wldth«>
1250
2000
Fill to
Depth
Below
MLW
(FT)
Existing
to Depth
Below
MLW
(FT)
Volume
Silt
Volume
(CY)
3' Cap
Volume
(CY)
Total
Silt/Cap
(CY)
Closure
Dike
(CY)
(North)
(South)
2,600,000
Length«>
Wldlh»>
1,080,000
6,500
900
1200
4,200
15
15
21
26
268,109
294,4-10
274,539
117,912
542,649
412,352
130,000
255,600
Costs
(North)
(South)
Parent for Dike »
Parent for Cap but to MBDS °
Sand for Cap «
Parent to MBDS *
Note 1: There Is a shortfall of parent material If this site used alone.
The negative cost when combined with Sub-E cancels a portion of
the 250,000 cy parent material shown being sent to MBDS.
Parent
Material
(CY)
385,600
392,451
(60,000)
Dredging
Cost
$1,867,829
$2,051,264
$2,394,576
$3,045,422
$3,924,513
($465,600)
Design and
Constr. Mgt
Cost (7%)
$161,000
$174,000
$168,000
$213,000
$275,000
($33,000)
Contingency
Cost
(25%)
$507,000
$556,000
$641,000
$615,000
$1,050,000
($125,000)
Total
Cost
Silt
$2,535,829
$2,781,264
$3,203,576
$4,073,422
$5,249,513
($623,600)
Unit Cost
for Silt
«/CY)
$11.35
($11.34) w/no cap
$11.34
$19.71 w/sandcap
<• See note 1
(Portion) $3,019,264 Rock
$14,989,754
$20,239,267 w/sandcap
ASSUMPtlONS
Footprint (area) planlmetered from navigation chart.
Existing depth calculated from navigation chart soundings within area.
Fill depth Is finished depth Including a 3 foot cap.
Design effort Involves minimal site hydrographlc survey ($20,000) and benthlc and fish studies ($10,000).
Dredging costs - silt • $8.36, parent « $7,76, cap « $6.21, dike « $6.21.
Cap and dike both consist of parent material.
Parent material to MBDS Is ratio of slK/(lolal sill) x total parent.
-------
Subaqueous E
TABLE 3-17 (CONTINUED). COST ESTIMATE FOR SUBAQUEOUS DPRESSION OPTION FOR BHNEP SILT DISPOSAL
Footprint Perimeter
(Sq Ft) (FT)
Length=>
Width=>
850
4100
Fill
Depth
Below
MLW(FT)
Existing
to Depth
Below
MLW(FT)
Volume
Silt
Volume (CY)
3' Cap
Volume (CY)
Total
Silt/Cap (CY)
Closure
D)ke(CY)
3,485,000
9,900
15.8
591,164
362,280
973,444
62,200
Costs
Parent for Dike =
Parent for Cap but to MBDS =
Sand for Cap =
Parent to MBDS =
ASSUMPTIONS
Parent
Material
(CY)
62,200
382,280
31.0,000
Dredging
Cost
$4,128,298
$387,506
$2,966,490
$3,822,796
$2,405,600
Design and
Constr. Mgt
Cost (7%)
$319,000
$27,000
$208,000
$268,000
$168,000
Contingency
Cost
(25%)
$1,112,000
$104,000
$794,000
$1,023,000
$643,000
Total
Cost
Silt
$5,559,298
$518,506
$3,968,490
$5,113,796
$3,216,600
Unit Cost
for Silt
($/CY)
$19.34
w/sand cap
$11.28
w/no cap
Footprint (area) planimetered from navigation chart.
Existing depth calculated from navigation chart soundings within area.
Fill depth is finished depth including a 3 foot cap.
Design effort involves minimal site hydrographic survey ($20,000) and benthic and fish studies ($10,000).
Dredging costs - silt = $8.38, parent = $7.76, cap = $6.23, dike = $6.23.
Cap and dike both consist of parent material.
Parent material to MBDS is ratio of silt/(total silt) x total parent.
(Portion) $3,172.845 Rock
$16,435,739
$21,549,535 w/sand cap
-------
IN-CHANNEL
TABLE 3-18. COST ESTIMATE FOR IN-CHANNEL DISPOSAL OPTIONS FOR BHNIP SILT
Volume
Cell Cell Number SHI Parent Extra Parent 3' Cap
size Depth of Removed Removed Removed Required
Cells per cell per cell per cell per cell
Mystic River
200x600 48 2
50 1
65 6
56 1
60 2
65 7
70 3
150x500 65 1
60 1
70 1
Inner Confluence
200x600 48 1
55 4
60 4
Chelsea
200x500 55 3
56 2
68 4
60 1
65 2
160x600 49 7
9,300 16,100
9,300 16,000
9,300 16,000
9,300 16,100
9,300 16,100
9,300 16,100
9,300 16,000
7,300 12,300
7,300 12,300
7,300 12,300
9,300 16,100
9,300 16.000
9,300 16,100
9,300 16,000
9,300 16,100
9,300 16,100
9,300 16,100
9,300 16,100
7,300 12,200
19,600 10,400
24,900 10,400
36,000 10,400
37,800 10,400
44,000 10,400
49,400 10,400
52,600 10,400
24,900 7,700
29,200 7,700
30,900 7.700
19,600 10,400
36,000 10,400
44,000 10,400
36,000 10,400
37,800 10,400
41,100 10,400
44,000 10,400
49,400 10,400
16,100 7,700
Silt Total Silt
Capacity Removed
per cell
9,100 18,600
14,600 9,300
26,600 55,800
27,400 9,300
33,600 18,600
39,000 65,100
42,100 27,900
17,200 7,300
21,500 7,300
23,200 7,300
9,100 9,300
25,600 37,200
33,600 37,200
26,600 27,900
27,400 18,600
30,700 37,200
33,600 0
39,000 18,600
8,400 0
412,500
Remaining In Channel Capacity «
ASSUMPTIONS
$8.29 'Unit Cost of Silt
Remaining Silt to In Channel •
$7.76 ° Unit cost of Parent (even If used as cap)
$6.29 = Unit cost of Extra Parent
$10.00 "Unit Cost of Cap
1,684,000 n Total Parent
1,099,100 » Total SIN
Remaining: Parent to MBDS =
Total Parent ' Total
Removed Extra Parent
Removed
32,200
16,000
96,000
16,100
32,200
112,700
48,000
12,300
12,300
12,300
16,100
64,000
64,400
48,000
32,200
64,400
0
32,200
0
711,400
1 X 33600 -f 7 X 8400 >
1099100-412500°
1684000-711400 =
39,000
24,900
216,000
37,800
88,000
345,800
157,500
24,900
29,200
30.900
19,500
144,000
176,000
108,000
75,600
164,400
0
98,800
0
1,780,300
Total Silt Cap Dredging
Capacity Volume Coet
(CY)
18,200
14,500
163,600
27,400
67,200
273,000
126,300
17,200
21,600
23,200
9,100
102,400
134,400
76,800
64,800
122,800
0
78,000
0
1,320,400
92,400
686,600
972,600
20,800
10,400
62,400
10,400
20,800
72,800
31,200
7,700
7,700
7,700
10,400
41,600
41,600
31,200
20,800
41,600
0
20,800
0
459,900
$857,000
$462,000
$3,190,000
$544,000
$1,166,000
$4,317,000
$1,906,000
$390,000
$417,000
$427,000
$429,000
$2,127,000
$2,331,000
$1,895,000
$1,088,000
$2,258,000
$0
$1,234,000
$0
$24,738,000
$5,692,000
$7,647,000
Design and Contingency
Const. Mgt Cost
Cost (TA) (25V.)
$60,000
$32,000
$223,000
$38,000
$82,000
$302,000
$133,000
$27,000
$29,000
$30,000
$30,000
$149,000
$163,000
$112,000
$76,000
$168,000
$0
$86,000
$0
$1,730,000
$398,000
$528,000
$229,000
$124,000
$853,000
$146,000
$312,000
$1,155,000
$510,000
$104,000
$112,000
$114,000
$115,000
$569,000
$624,000
$427,000
$291,000
$604,000
$0
$330,000
$0
$6,619,000
$1,523,000
$2,019,000
Total
Cost
$1,146,000
$618,000
$4,266,000
$728,000
$1,560,000
$5,774,000
$2,649,000
$521,000
$558,000
$571,000
. w
$574,000
$2,845,000
$3,118,000
$2,134,000
$1,465,000
$3,020,000
$0
$1,650,000
$0
$33,087,000
$7,613,000
$10,094,000
Unit Cost for SIN
$30.31
$37.03
w/o parent
Rock
Grand Total
$7.081.600
$57,875,600
-------
Mol Jburgar 2
TABLE 3-19, COST ESTIMATES FOR AQUATIC BORROW PIT OPTION FOR B11NIP SILT DISPOSAL
Footprint Perimeter
(SqFt) (FT)
Longlh«>
Wldlh">
2000
1873
Existing
Depth
BflloW .
MLW(FT)
Excavate
to Depth
Below
MLW(FT)
Silt
Volumi(CY)*
Volume
3' Cap
Volum«(CY)*
Total
Volum«(CY)
Drtdglng
Cost
Costs
Design and Con
Constr. Mgt
Co«t(7%)
tlngtncy
Cost
(25%)
Total
Cost
sm
Unit Cost
for Silt
(S/CY)
3,740,000
7,746
80
83
1,319,618
412,361 1,731,879 $24,926,242
$1,775,000
$6,676,000
$33,376,242
$30.37
* Total volume of sediments and cap exceed estimated yield of eand/gravel
(It Is possible that yield did not account for lenses ofsltl) Dredging
Cost
Parent to MBDS" 1,884,000 $13,087,840
Malsburger 7
Footprint Perimeter
(SqFt) (FT)
Length"> 2500
Wldlh-> 2107
5.267,500 9,214
ASSUMPTIONS
Footprint (area) provided by I
Exlstlna death- obtained from
Existing Excavate Volume
Depth to Depth
Below Below Silt
MLW(FT) MLW(FT) Volume (CY) Volu
3' Cap Total Dredging
me (CY) Volume (CY) Cost
80 90 1,319,497 580,683 1,900,180 $27,400,430
Dredging
Cost
Parent to MBDS " 1 ,684,000 $1 3,067,840
taimandeau (possibly from Melsburger report).
navigation chart soundings.
Design and
Constr. Mgl
Cost(1%)
$131,000
Design and
Constr. Mgt
Cost (7%)
$1,948,000
Design and
Constr. Mgt
Cost (1%)
$131,000
Contingency
Cost
(25%)
$3,300,000
Costs
Contingency
Cost
(26%)
$7,337.000
Contingency
Cost
(25%)
$3,300,000
Total
Cost
Parent
$16,498,840
$49,875,082
$7,081,600 Rock
$56,956,582
Total
Cost
$36,685,430
Total
Cost
Parent
$16,498,840
$53,184,270
$7,081,500 Rock
Unit Cost
for Silt
($/CY)
$33.38
Proposed sediment thickness Is the difference between existing and excavated depths minus the 3 foot cap.
Side slopes of 1 vertical to 3 horizontal were essumed.
Volumes shown are dredged volumes (expansion of dredged material has not been applied).
Dredging costs account for dredging CAD and Boston Harbor sediments. (Mateburg mat.» $6.65, parent - $7.76, silt • $9.18).
No value was assigned to material excavated from disposal sites.
Design effort Invloves minimal site hydrographies surveys ($20,000)and benthte and fish studies ($10,000).
Contingency Is 25%.
$80,285,770
-------
TABLE 3-19 (CONTINUED). COST ESTIMATES FOR AQUATIC BORROW PIT OPTION FOR BHNIP SILT DISPOSAL
CAD (Spectacle)
Footprint Perimeter
$4.71, silt = $8.42, parent = $7.76)
Design effort Involves minimal site hydrographlc surveys ($20,000) and benlhlc and fish studies ($10,000).
Contingency Is 25%.
Silt curtain was assumed to consist of two square enclosures 200' on a side and 18' deep.
No cost was assumed for deployment of silt curtain.
$96,000 $1,237,000 $4,644,000 $23,221,430
Design and
Const. Mgt
Cost(1%)
Contingency
Cost
(25%)
Total
Cost
$21,13
$131,000 $3,267,000 $16.465.840
$39,687,270
$7,081,500 Rock
$46,768,770
-S5
-------
TABLE 3-20. COSTS FOR ALTERNATIVE TREATMENT TECHNOLOGIES FOR BHNIP
DREDGED MATERIAL
TECHNOLOGY TYPE
Thermal
Solvent Extraction, Soil Washing
and Other Chemical Treatments
Biotreatment
Solidification/Stabilization
Physical, Mechanical & Landfill
Disposal
COST PER TON
$75 to $120
$80
$135
$90
$55
COST PER CUBIC YD
$113 to $180
$120
$200
$135
$80
-------
TABLE 3-21. COST ESTIMATES FOR USING EXISTING AQUATIC DISPOSAL SITES FOR BHNIP SILT DISPOSAL
Boston Lightship
MBDS
Note 1 =>
Note2=>
Note 3 =>
Note 4 =>
Footprint
(SF)
8,454,800
8,454,800
8,454,800
8,454,800
Silt
Volume
(CY)
1,107,500
Silt
Volume
(CY)
1,107,500
1,099,100
1,099,100
1,099,100
3' Cap
Volume
(CY)
1,055,500
3' Cap
Volume
(CY)
1,055,500
1,055,500
1,055,500
1,055,500
Remaining
Parent
Volume
(CY)
628,100
Remaining
Parent
Volume
(CY)
628,100
628,100
628,100
628,100
Dredging
Cost
$23,352,370
Dredging
Cost
(perCY)
$23,774,261
$23,693,033
$18,818,977
$10,628,297
Design and
Constr. Mgt
Cost (7%)
$1,655,000
Design and
Constr. Mgt
Cost(1%)
$258,000
$257,000
$208,000
$126,000
Contingency
Cost (25%)
$5,838,000
Contingency
Cost (25%)
$6,008,000
$5,988,000
$4,757,000
$2,689,000
Total
Cost
$30,845,000
Total
Cost
$30,040,000
$29,938,000
$23,784,000
$13,443,000
$7.081,500
. Unit Cost
for Silt
($/CY)
$15.87
Unit Cost
for Silt
($/CY)
$13.05
$27.24
$21.64
$12.23
Rock
ASSUMPTIONS
Dredge costs - silt = $9.67,parent and cap = $7.76.
Unit cost for silt disposal = (dredge cost for silt + dredge cost for cap) divided by sift volume
Cap volume calculated for 3' cap over footprint of 9,500,000 SF.
Volumes shown are dredged volumes (expansion of dredged material has not been applied).
Design effort involves minimal site hydregraphic surveys ($20,000).
Note: 1) Unit cost doesn't consider remaining parent material or design/contingencies costs.
2) Unit costs include all parent material, design and contingencies costs, (expanded vol)
3) Unit cost doesn't consider remaining parent material but does consider design/contingencies costs, (expanded vol)
4) Unit cost includes only silt, design and contingencies it does not include cap.
$37,019,500
-------
TABLE S-22.
COMPANIES SENT QUESTIONNAIRES FOR INFORMATION TREATMENT
TECHNOLOGY FOR THE BOSTON HARBOR NAVIGATION IMPROVEMENT
PROJECT
COMPANY
RESPONSE
Retech, Inc., Ukiah, CA
IT Corporation, Knoxvffle, TN
ConTeck Environmental Services
Canonie Environmental Services Corp.
(SoURech ATP Systems, Inc.)
ECOVA Corporation
Carlo Environmental Technologies., Inc.
Separation and Recovery Systems, Inc.
Maxymiflian Technologies
(formerly Clean Berkshires, Inc.)
Hrubetz Environmental Services, Inc.
Seaview Thermal Systems
Remediation Technologies, Inc.
SRE,Inc.
ART International, Inc.
CF Systems Corp.
Dehydro-Tech Corp.
BergmannUSA
Cleantech of Arkansas, Inc.
None
None
Yes
Yes
None
Yes
Yes
Yes
Yes
None
None
None
Yes
None
Yes
None
None
-------
TABLE 3-22 (CONTINUED)
COMPANIES SENT QUESTIONNAIRES FOR INFORMATION TREATMENT
TECHNOLOGY FOR THE BOSTON HARBOR NAVIGATION IMPROVEMENT
PROJECT
COMPANY
RESPONSE
OHM Corporation
Grace Dearborn, Inc.
MEET
Marine Remediation Systems, Inc.
Concurrent Technologies Corp.
LADS Systems, Inc.
Applied Environmental Recycling Systems
ReSHAPE Corporation
Laidlaw Waste Systems, Inc.
Bardon Trimount Inc.
WEB Engineering Associates, Inc.
IWT Corporation
GeoCon
Modell Environmental Corporation
Commercial Paving Co., Inc.
(Commercial Recycling Systems)
Charles Group Inc.
Waterways Experiment Station
Yes
None
None
None
None
Yes
None
None
Yes
None
None
None
None
None
Yes
None
None
-------
TABLE 3-22 (CONTINUED)
COMPANIES SENT QUESTIONNAIRES FOR INFORMATION TREATMENT
TECHNOLOGY FOR THE BOSTON HARBOR NAVIGATION IMPROVEMENT
PROJECT
COMPANY
RESPONSE
Zenon Environmental foe.
BioSafe, Inc.
Soil Technology
Resources Conservation Company
None
Yes
Yes
None
-------
TABLE 3-23. TECHNOLOGY SURVEY QUESTIONNAIRE RESPONSES
The following abbreviations and notations apply to the following Table 3-23.
b bench scale
c commercial scale
d day
D demonstration
Dm demobilization
dw dewatering
el electricity
hrs hours
1 laboratory scale
M mobilization
m month
mm minutes
Ms moisture
mt metals
N No
NA not available/applicable
ng natural gas
o organics
pp proprietary
pt pilot scale
sc screen
sft square feet
t theoretical
Y Yes
-------
TABLE 3-23. TECHNOLOGY SURVEY QUESTIONNAIRE RESPONSES
-0
COMPANY
TECHNOLOGY TYPE
EFFECTIVENESS
Demonstrated Through-Put cy/d
i/laximum Through-Put cy/d
Meet Target Levels
Waste Bv-Pfoducts
Applicable to Dredged Material
Efficiencies in Scale
Minimum Contaminant Concentr
arocessinq Time
MPLEMENTABILITY
're-Treatment Requirements
Mob-Demob Requirements
Space Requirements
Traffic Impacts
.oqistics
Special Fabrication
Building Requirements
Availability of Technology
Mumber of Handling Events
Environmental Impacts
3ermittability
Site Safety
Environmental Constraints
Marketability of Residuals
COST DATA
Estimated Price Range
Factors Affecting Price:
Initial Contaminant Concentrat
Target Contaminant Concentre
Quantity of Waste
Characteristics of Residuals
Labor Rates
Moisture Content
Facility Preparation
Waste Handling
Characteristics of Material
Utility/Fuel Rates
ART
International
Solvent
Extraction
BloSafe
Thermal
Destruction
Carlo
Environmental
Technology
Thermal
Desorptlon
2
3
0-Y M-N
Yes
Yes-b&pt
NA
None
None
1000
8000
0-Y M-Y
Yes
Yes-b&pt
Yes
NA
NA
525
600
0-Y M-N
No
Yes
Yes
None
600 cy/d
Yes-sc&dw
M-2m,Dm-1m
1 5,000 sft
Truck
1 5,000 sft
None
Yes
Pp.l.pt
Two
Air
Air, Water
Yes
None
Yes
Yes-sc&dw
M-2m,Dm-2m
NA
None
NA
None
Yes
C
Varies
None
Water
No
None
Yes
Yes-sc&dw
M-2wk,Dm-NA
70,000 sft
None
Land
None
Yes
C
Three
Air
Air
No
Tm.Ms
Yes
$55-$65/ton
2
4
5
4
2
3
3
4
5
$122/ton
1
9
2
4
10
6
7
3
5
8
$28-$40/ton
8
5
6
10
7
4
9
3
1
Commercial
Recycling
Systems
Solidification
Stabilization
1000
NA
0-Y M-Y
No
Yes-c
Yes
None
Varies
Yes-dw
M-2d,Dm-NA
10,000 sft
Truck
Land
None
Yes
Pp,l,c
Seven
Water
Air, Water
No
Tm
Yes
$55-$95/ton
8
9
10
6
1
5
4
3
7
-------
TABLE 3-23 (Continued) TECHNOLOGY SURVEY QUESTIONNAIRE RESPONSES
U)
1
COMPANY
TECHNOLOGY TYPE
ConTeck
Environmental
Services
Thermal
Desorption
Dehydro-Tech
Corporation
Solvent
Extraction
Hrubetz
Environmental
Services, Inc.
Thermal
Desorption
LADS
System, Inc
Thermal Solid/
Stabilization
EFFECTIVENESS
Demonstrated Through-Put cy/d
Maximum Through-Put cv/d
Meet Target Levels
Waste By-Products
Applicable to Dredged Material
Efficiencies in Scale
Minimum Contaminant Concentr
Processing Time
750
360 t/d
0-Y M-N
No
Yes
Yes
None
20 min
50 t/d
NA
0-Y M-N
Yes
Yes-t
Yes
None
1-2hrs
10
NA
0-S M-N
Yes
Yes-t
NA
NA
Varies
None
1000
0-NA, M-Y
Yes
Yes-l
Yes
None
hrs
IMPLEMENTABILITY
Pre-Treatment Requirements
Mob-Demob Requirements
Space Requirements
Traffic Impacts
Logistics
Special Fabrication
Building Requirements
Availability of Technology
Number of Handling Events
Environmental Impacts
Permittability
Site Safety
Environmental Constraints
Marketability of Residuals
Yes-sc&dw
M-2wk,Dm-NA
39000 sft
Truck
w, ng, el
Yes
Yes
C
Five
Air, sec
Air, Water
Yes
Tm, Ms
Yes
Yes-sc
M-2yr,Dm-NA
NA
Varies
NA
None
Yes
Pp,l,pt,c
NA
None
Air, Water
No
None
No
Yes-sc&dw
M-1 wk,D-1 wk
6,700 sft
Unknown
Land
Yes
None
C
Varies
Air
NA
Air, Noise
Ms
No
Yes-sc&dw
M-1-2yr,D-1wk
NA
Truck
Barge
None
None
• Pp,Pt
Six
Air, Water
Air, Water
Noise, Odors
No
COST DATA
Estimated Price Range
Factors Affecting Price:
Initial Contaminant Concentrati
Target Contaminant Concentra
Quantity of Waste
Characteristics of Residuals
Labor Rates
Moisture Content
Facility Preparation
Waste Handling
Characteristics of Material
Utility/Fuel Rates
$26-$65/ton
6
2
3
8
6
1
7
5
4
5
$50-$150/ton
1
3
1
2
2
3
$40-$100/ton
9
5
6
10
7
1
8
3
2
4
$90-$130/ton
1
3
2
-------
I
TABLE 3-23 (Continued) TECHNOLOGY SURVEY QUESTIONNAIRE RESPONSES
COMPANY
TECHNOLOGY TYPE
EFFECTIVENESS
Jemonstrated Through-Put cy/d
>yiaximum Through-Put cy/d
Meet Target Levels
Waste Bv-Products
Applicable to Dredged Material
Efficiencies In Scale
Minimum Contaminant Concentr
Processing Time
IMPLEMENTABILITY
Pre-Treatment Requirements
Mob-Demob Requirements
Space Requirements
Traffic Impacts
oaistics
Special Fabr cation
iuilding Requirements
Availability of Technology
Number of Handling Events
Environmental Impacts
Permittability
Site Safety
Environmental Constraints
Marketability of Residuals
COST DATA
estimated Price Range
Factors Affecting Price:
Initial Contam nant Concentrati
Target Contaminant Concentra
Quantity of Waste
Characteristics of Residuals
Lahor Rates
Moisture Content
Facility Preparation
Waste Handling
Characteristics of Material
Utility/Fuel Rates .
Laldlaw
Waste
Systems
Lined
Landfill
Maxymillian
Technologies
Thermal Dest/
Incineration
OHM Remediation
Services Corporation
Slurry-Phase
Bio-Treatment
2500 1
2500
NA
NA
Yes
NA
NA
NA
None
NA
NA
NA
NA
NA
Once
NA
NA1
No
NA
NA
1 $50-$65/ton
—
200-1 400
200-1400
0-Y M-N
Yes-d
Yes
1 0-30 min
M-1-2m,D-1m
None
Land
None
Yes
Six
Air, Water
None
MA
$40-$200/ton
" 8~
9
"To"
6
4
5
2
3
7
135
275
0-Y M-N
Yes-b
Yes
5-15 day
NA
NA
None
None
None
Yes
__ —
Four
Water
No
fm
$130-$140/ton
2
Separation and
Recovery Systems
Thermal
Desorption
100
300
0-Y M-N
Yes
Yes-t
Yes
None
NA
M-3m,D-1m
17,000 sft
None
10,000 sft
None
Yes
C
Two
None
Air, Water
No
Tm, Ms
Yes
$80-$225/ton
5
9
10
7
8
SoilTeoh
ATP Systems, Inc.
Thermal
Desorption
200
700
0-Y M-N
No
Yes-c
No
None
40 min
Yes-so&dw
M-2m,D-2m
62,500 sft
None
Storage
Yes
Yes
Four
None
Air
Air, Odor
Yes
$50-$100/ton
To"
-------
TABLE 3-24. TECHNOLOGY RATING SUMMARY
COMPANY
NAME
ART Intern
Biosafe
Carlo Envi
Commercl
ational, Inc.
ronmental
al Recvclina
Conteck Environmental
Dehydro-T
Hrubetz Et
ech Corp.
wironmental
LADS System. Inc.
LaidlawW
Maxymillia
OHM Rem
Separatior ,
aste Systems
n Technologies
ediation Services
i and Recoverv
SollTech ATP Systems
TREATMENT
TECHNOLOGY
Solvent Extraction
Thermal Destruction
Thermal Desorption
S/S
Thermal Desorption
Solvent Extraction
Thermal Desorption
Thermal S/S
Lined Landfill
Thermal Destruction
Bio-treatment
Thermal Desorption
ThermaLDesqrptiqn
STATE OF
DEVELOPMENT
Pilot
Demonstrated
Demonstrated
Demonstrated
Demonstrated
Demonstrated
Demonstrated
Pilot
Demonstrated
Demonstrated
Demonstrated
Demonstrated
Demonstrated
APPLIED TO
DREDGED
MATERIAL
No
No
Yes
Yes
No
No
No
Yes
Yes
Yes
No
No
Yes
AVAILABILITY
Proprietary
Commercial
Commercial
Commercial
Commercial
Proprietary
Commercial
Emerging
Commercial
Commercial
Commercial
Commercial
Commercial
RATING
EFFECTIVENESS
M=0, 0=4
M=0, 0=4
M=0, 0=4
M=3, 0=3
M=0, 0=4
M=0, 0=4
M=0, 0=3
M=3, 0=NA
M=3, 0=3
M=0, 0=3
M=0, 0=3
M=0, 0=3
M=0, 0=4
MPLEMENTABILITY
2
3
3
4
3
3
3
2
4
4
3
3
4
COSTS
3
3
3
3
3
3
3
3
3
COMPOSITE
SCORE
9
9
10
,,; 13
10
10
9
7
13
9
9
8
11
-------
TABLE 3-25.
PORT1
Gloucester Inner
Harbor
Salem Harbor
Beverly Harbor
Lynn Harbor
PORTS MEETING MINIMUM DEPTH
REQUIREMENTS FOR TRANSFER OF BHNIP
MATERIAL TO UNLINED MUNICIPAL LANDFILLS
DEPTH RELATIVE PilOXIMAL U^S
TOMLW
LANDFILLS2
varies, > 15± ft.
30± ft.
varies, > 19+ft.
13 ft. in 1970 from
Feb. '78 NOAA
chart, No. 13275
Gloucester, Rockport, Rowley, Topsfield,
Haverhill
Topsfield, Middleton, Lowell, Reading,
Woburn, Andover
Topsfield, Middleton, Lowell, Reading,
Woburn, Andover
Newton, Reading, Lowell, Reading
PORT DEPTH RELATIVE
TOMLW
MUNICIPALITIES
Chelsea Creek
East Boston
South Boston
Weymouth, Fore
River
varies, but sufficient
varies, but sufficient
varies, but sufficient
varies, > 22 ft.
Plymouth Cordage 11 ft. (1977) at MLW
New
Bedford/Fairhaven
varies, > 15 ft.
Mount Hope Bay varies, > 15 ft.
Natick, Needham, Newton, Milton, Millis
Natick, Needham, Newton, Milton, Millis
Natick, Needham, Newton, Milton, Millis
Milton, Needham, Cohasset, Newton,
Norwood, Sharon, Holbrook, Rockland,
Weymouth, Scituate
Middleboro, Duxbury, Marshfield, Bourne,
Lakeville, Plymouth, Kingston, Rockland,
Scituate
New Bedford, Fairhaven, Dartmouth,
Westport, Freetown, Mattapoisett,
Lakeville, Middleboro, Raynham, Taunton
Freetown, Lakeville, Attleboro, Taunton,
Raynham, New Bedford, Fairhaven,
Middleboro
1 From: Designated Port Areas as defined in the Wetlands Protection Act Regulations (3 10 CMR
10.26).
2 From: Central Artery/Third Harbor Tunnel Clay Distribution List, July 5, 1994.
A
3- tf;
-------
TABLE 3-26. SCREENING MATRIX FOR DETERMINING THE LEAST ENVIRONMENTALLY DAMAGING
PRACTICABLE ALTERNATIVE FOR DISPOSAL OF SILT FROM THE BHNIP.
TYPE
LANDFILL
LAND-BASED-
Inland
Coastal
AQUATIC
Shoreline
(Partial
Fill)
Oc\.
PERMANENT
HABITAT
SITE LOSS OR
ALTERATION
E. no
Bridgewater
Fitchburg/ no
Westminster
Plainville/ no
Laidlaw
Woburn no
Wrentham yes
Everett yes
Squantum yes
Point
Amstar altered
Cabot Paint altered
Little altered
Mystic
Channel
WATER
QUALITY
EXCEEDENCES SOCIOECONOMIC REASONABLE
BEYOND EFFECTS CAPACITY
DISPOSAL
SITE
no displacement no
of other
users
no displacement no
of other
users
no displacement no
of other
users
no traffic no
no traffic yes
no minor no
no neigborhood, yes
traffic
mitigated displacement no
of MWRA pier
mitigated minor no
mitigated neighborhood yes
BENEFICIAL USEb
minor
minor
minor
cap landfill
no
no
no
contain
contaminants
contain
contaminants
contain
contaminants
LEAST
ENVIRONMENTALLY
COST DAMAGING
($/cy) ALTERNATIVES
$62
$108
$94
$69
$62
$76
$45-
$50
$37
$278
$30
*
*
*
*
*
*
-------
s
* O^
*^ ^^
00
TYPE SITE
Mystic
Piers
Reserved
Channel
Revere
Sugar
Subaqueous Subaqueous
B
Subaqueous
E
In-Channel Chelsea
Creek
Inner
Confluence
Mystic
River
Borrow pit Meisburger
2
Meisburger
7
Spectacle
Island CAD
PERMANENT
HABITAT
LOSS OR
ALTERATION
altered
altered
altered
altered
altered
no
no
no
no
no
no
WATER
QUALITY
EXCEEDENCES
BEYOND
DISPOSAL
SITE
mitigated
mitigated
mitigated
yes
yes
mitigated
mitigated
mitigated
no
no
mitigated
SOCIOECONOMIC
EFFECTS
minor
neighborhood,
traffic
minor
minor
minor
minor
minor
minor
displacement
of fisheries
displacement
of fisheries
minor
REASONABLE
CAPACITY
no
yes
no
yes
yes
yes
no
yes
yes
yes
yes
BENEFICIAL OSEb
contain
contaminants
resource
enhancement;
contain
contaminants
contain
contaminants
no
no
no
no
no
minable resource
minable resource
minor
COST
($/oy)
$35
$85
$35
$20
$19
$37
$37
$37
$31
$33
$21
LEAST
ENVIRONMENTALLY
DAMAGING
ALTERNATIVES
*
*
*
*
*
*
*
Existing
MBDS .
no
no
minor
yes
no
$16
-------
TYPE
PERMANENT
HABITAT
SITE LOSS OR
ALTERATION
HATER
QUALITY
EXCEEDENCES
BEYOND
DISPOSAL
SITE
'SOCIOECONOMIC REASONABLE COST
EFFECTS CAPACITY BENEFICIAL USEb ($/oy)
LEAST
ENVIRONMENTALLY
DAMAGING
ALTERNATIVES
Disposal
Site
TREATMENT
Boston
Light Ship
Various
no
no
no
no
displacement
of fisheries
minor
yes
yes
no
potentially
$27
$55-
$200
*
£200,000 cy
through site preparation or use of silt, parent material not included since it has universal benefit
cost could be reduced by beneficial use of mined sediments
ff
-------
-------
-------
H iiiiiiiii iiiiiiiiiiiiiiii 11 lib lib iiiiiii iiiiiiH iiiiiii ^m iiiiiiiiiiiiiiiiiiiiiiii nil iiiiiiH^ In i ill 11 iiiiiiiiiiiliiiiiii iiiiiii iii'iliiiiilii i iiiiiii i iiiiiiiiliiiii iiiiiii 11 nil
1 ill iiiiiiiiiiiiiiiiiii iiiiiiiiiiiiiiiiiiiii
iiiiiiiiiiii^ iiiiiii
iiiiiiiiiiiiiiiiiii i iiiiiii in nil 11 iiiiiii
iiiiiiiiiiiiiiiiiiiii iiiiiii
IIIIIIIIIIIIIIIIIII
IIPI i i
iiiiiiiiiiiiiiiiiii iiiiiiiii PI iiiiiiiii11
i i ni iiiiiii 11 iiiiiiiiiii iiiiiiiiiiiiiiiiiiiii i iiiiiiiii (
Ml III I lllllllllllllllllllllll I Illllllllll 111
111 III IIIIIII lllllllllllllllllllllll Illllllllll I III Illllllllll
111 III IIIII IIIIIII 111 Illllllllll Illllllllll II 111 111
i Hi 11 nni in1 'ill1 IP mi iiiii
lllllllllllllllllllllll lllllllllllllllllllllll II III IIIIIIIII II I Illllllllll III IIIII II III III IIIIIIIII III III I Illllllllll 11
liiil
-------
Chapter Four: Selection Of Preferred Disposal
Location
This Chapter provides a detailed
environmental analysis of potential disposal
sites to determine the least environmentally
damaging and practicable alternative for
the disposal of silt from the BHNIP.
Under NEPA (40 CFR 1505.2) and MEPA
(MGL c.30, s.61-62h and 301 CMR
11.00), the BHNIP must demonstrate that
•the proposed project avoids or minimizes
any adverse impacts to environmental
quality. This analysis must consider all
applicable local, State and Federal
regulations, including Section 404 of the
Clean Water Act and the 404(b)(l)
Guidelines (40 CFR 230.20-.54), the
Massachusetts Wetlands Protection Act
(MGL c.131, s.40) and its implementing
regulations (310 CMR 10.00), the
Massachusetts Waterways Act and its
implementing regulations (310 CMR 9.00),
and consistency with the Massachusetts
Coastal Zone Management Program
regulatory and non-regulatory policies, and
federal consistency (MGL c.6A, s.2-7;
c.21a; c.706; and c.1230) and their
implementing regulations (301 CMR 20.00
and 21.00).
The selection process involves comparison
of the long-term and short-term impacts
that would arise through implementation of
each alternative. The "short-list" of land-
based and aquatic-based sites, selected as a
result of the site screening process
described in Chapter 3 (see Table 3-1), is
evaluated based on direct and indirect
impacts within each alternative. The
evaluation of environmental impacts at
potential disposal sites includes information
developed as a result of comments on the
DEIR/S. The information collected since
the DEIR/S caused us to reduce the
available footprint of the Wrentham site.
For example, to avoid impacts to Zone n
aquifer protection area. Investigation at
the aquatic disposal sites in the fall of 1994
confirmed our understanding of the
biological conditions at the aquatic sites as
evaluated hi the DEIR/S.
In performing the LEDPA, identification
of the least environmentally damaging
alternative(s) is performed separately from
the practicability analysis. These two
issues have been separated in response to
several comments received during review
of the DEIR/S. Environmental impacts
now receive more emphasis than
practicability, and thus is more hi keeping
with the intent of the above-stated
regulations. Separating the analyses also
permits identification of sites that may be
more suitable for other disposal projects or
for disposal of future maintenance material
from the BHNIP.
For example, while a number of the sites
discussed in this section would have
insufficient capacity to be used as the sole
4-1
-------
repository of the silt from the BHNIP,
they could be of interest for a combination
of alternatives, if practicable, or a smaller
project in the future. This assessment of
environmental effects addresses these sites
from the dual perspectives of suitability for
the BHNIP and for future maintenance or
an unidentified future project. Site
capacity is relevant in comparing
environmental impacts because the use of
several sites requires construction
disturbances at each and therefore, have
greater cumulative environmental impacts.
The parallel process for identifying the
most practicable alternative(s) is based on
an assessment of technical requirements
and constraints, and a comparison of cost
estimates for each site. Selection of the
LEDPA results from the weighting of the
least environmentally damaging
alternatives with the practicability analysis
results.
The following section identifies the least
environmentally damaging alternative
among the short-listed, land-based sites.
4.1 LAND-BASED SITES
Land-based sites are being considered in
the context of providing an alternative for
placement of approximately 200,000 cy, in
the event that there are volume, suitability,
permitting or practicability constraints
from other alternatives that cannot be
resolved. Potential land-based sites
include the short-list of coastal sites and
inland sites identified on Table 3-1.
Consideration of the land-based sites
involves two aspects: generic issues which
are applicable to all land-based sites; and
site-specific issues which are unique to
individual sites. The following land-based
sites are considered in this discussion:
Lined Landfills
• BFI-East Bridgewater Landfill
• Plainville Sanitary Landfill
• Fitchburg-Westminster Sanitary
Landfill
Coastal Sites
• Squantum Point
• Everett
Inland Sites
• Woburn
• Wrentham
Full descriptions of each site are provided
in Attachment 1 to this Volume.
4.1.1 Generic Issues
Use of any of the land-based sites for silt
disposal will require that the silt be
transported by barge to a waterfront
dewatering facility, off-loaded onto the
facility, dewatered, and loaded onto
trucks, rail cars, or barges for
transportation to the land-based disposal
site for final disposal. With each
additional handling and transportation step,
the potential for environmental impacts
increases. This section will address
several of the major issues unique to land-
based disposal, specifically dewatering and
hauling. Additionally, proposed use of
any inland site as a disposal facility
(monofill) would trigger a rigorous
4-2
-------
environmental site review under the
Massachusetts DEP Solid Waste Siting
Suitability regulations.
4.1.1.1 Dewatering
Land-based transport and handling logistics
require that the silt material be dewatered
prior to hauling to a land-based disposal
area. The present water content of the in-
situ silts ranges from 33%-74%, with an
average water content of 51 %. For
economical and safe handling,
transportation, and disposal, the water
content will need to be reduced so that no
free water is available.
Several dewatering options are available
for dredged materials. These include air
drying, mechanical drying, chemical
stabilization and mixing with dry material.
However, the sheer volume of silt material
to be dredged in the BHNIP eliminates
most options as environmentally risky, too
costly or slow (see Appendix I for a
description and assessment of dewatering .
technologies). Of the available options,
the least problematic and most economical
methods are mechanical dewatering with
belt presses, and air drying. A
combination of the two methods may be
most feasible.
Belt filter presses have been effectively
used on numerous projects of similar
magnitude, including dewatering of
municipal sludges, industrial processing
sludges and harbor silts. Belt filter presses
have the distinct advantages of being
mobile, requiring relatively little space,
being unaffected by precipitation and
temperature, and generating few odor
problems. A potential limitation to belt
filter presses on the BHNIP project is that
the silt has a high clay content that may be
difficult and slow to process with this
method.
A single 2-meter wide belt filter press is
truck-mounted and can process approxi-
mately 350 cy of silt per day, assuming a
24-hour operation. Six presses would be
required to process the silt from a 2,000
cy scow. At this daily rate, dewatering
200,000 cy would be accomplished in
approximately 4 months. The silt might
need to be mixed with water and a
polymer to achieve the desired consistency
for spreading on the presses. The leachate
from the presses could potentially be
recycled into the mixing tank for future
processing, thereby reducing the need for
water treatment. The recycled leachate
would be treated on-site using portable
flow-through filters to remove particulates
and contaminants prior to discharge into
the Harbor, in order to meet water quality
criteria.
To air dry the silts, a series of diked and
sealed asphalt containment cells would
need to be constructed at one or several
sites. Air drying estimates indicate that
approximately 5 acres are required to
handle 15,000 cy of silt, assuming a
maximum depth of 2 feet (see Appendix I).
An average of 14 days is anticipated, with
daily working of the silts, to reduce the
water content so that no free water
remains. Because this method relies on
suitable weather, its use would be limited
to the standard construction season (April-
November), and would not be efficient
during rainy or high humidity periods.
4-3
-------
Most of the water would be removed by
evaporation, although some discharge
would occur to remove surface water
picked up during the dredging process and
precipitation from storm events.
Assuming that a maximum of 56,000 cy of
silt can be dredged per week,
approximately 20 acres would be necessary
to air dry one week's worth of sUt.
Ideally, four 20-acre sites consisting of
four 5-acre cells each, for a total of 80
acres would be needed. This arrangement
would provide sufficient space to allow for
one site for off-loading silts, a second site
in which silts are .drying, a third site for
removing the dried silt, and a fourth site
for emergency storage during wet weather
or unexpected delays in transporting off-
site. A settling basin would be needed for
every 10 acres of cells to collect and treat
excess water prior to discharge back into
the Harbor. This dewatering arrangement
would be necessary to keep pace with
dredging and allow 200,000 cy of silt to be
dredged, dewatered and hauled to an
upland site in 6 to 8 weeks.
Sufficiently large areas of open space on
Boston Harbor are very limited.
Reduction of the space available for
dewatering would result hi lengthening the
time needed to complete the upland
disposal dredging. For example,
dedicating only one dredge to upland silt
disposal would cut the acreage needed in
half, to 40 acres, but would increase the
operational time of the dewatering facility
to approximately 12-14 weeks for 200,000
cy. The environmental and practicability
impacts relating to each option would need
to be weighed in order to determine if a
balance between area and schedule could
be achieved.
For both dewatering methods, loaded
barges would need to be brought by tug to
a berthing area near the facility for off-
loading. It is important that the
dewatering area(s) have the following
features hi order to allow efficient material
offloading, dewatering and offsite transport
of dewatered material:
• be located in direct proximity
to the Harbor
• have adequate water depth and
berthing facilities for loaded
barges
• have adequate land area
(minimum of 2 acres for belt
filter presses and 5 acres for
air drying) for barge
offloading, construction of a
dewatering facility and
operation of land based equip-
ment
Odor may be a major issue for dewatering
via air drying. Standard odor controls
such as daily cover and chemical agents
will be unsuitable because they function by
interfering with air exchange and
evaporation and would, therefore, impede
the drying process. Other potential
impacts from air drying include water
quality impacts from stormwater runoff
and removal of the surface water collected
during the dredging process, and noise
from the equipment operation.
Several representative waterfront areas
were identified for potential dewatering
sites. These sites are located near the
areas requiring dredging.
4-4
-------
The approximate capacities of several
possible dewatering areas are as follows:
Conley:
25 acres (overall area)
75,000 cubic yards (air drying
containment capacity)
Revere Sugar:
13 acres (overall area)
39,000 cubic yards (air drying containment
capacity)
Mystic Piers:*
3-8 acres (overall area)
15-24,000 cubic yards (air drying
containment capacity)
North Jetty:
15 acres (overall area)
45,000 cubic yards (air drying containment
capacity)
*Range includes potential of utilizing
adjacent space at Piers 48, 49 and 50.
These sites are representative. Their
actual availability depends on lease
agreements and other competing uses
occupying the sites when they would be
needed for dewatering.
4.1.1.2 Hauling
Transport of silt material to the land-based
sites from the dewatering facility will
require loading the dewatered silts from
the containment cell into barges for
hauling to Everett and possibly Squantum
Point (there is some potential for
dewatering directly at Squantum Point;
however, barge access will still be
required), or into trucks for all other
proposed land-based sites. Rail is a
possible option, although no active tracks
lead to any inland site so that off-loading
onto trucks would ultimately be required.
For barges to access either Squantum Point
or Everett, dredging would be needed to
create a berth for off-loading. An
estimated 2,300 cy of shallow subtidal
dredging would be necessary at Everett to
increase the existing 5-foot depth to the
needed depth of 10 feet (see Attachment
1). At Squantum Point, approximately
13,000 cy of subtidal and 6,500 cy of
intertidal dredging would be necessary to
gain shore access (Attachment 1). Some
of the intertidal habitat impacted at
Squantum Point may include salt marsh.
These dredged sediments would need to be
tested to determine what proportion, if
any, required special handling.
Trucking considerations include traffic,
noise, and roadwear in Boston and on the
secondary roads leading from major
highways to the Wrentham-495 and the
Woburn sites, and landfills. Assuming a
20 cy capacity for the trucks,
approximately 10,000 truckloads would be
required to transport the material, which
translates to a maximum of 238 truck trips
per day at the highest dewatering rate.
4.1.1.3 Solid Waste Siting Suitability
Disposal at the inland coastal sites would
require that the site meet DEP's solid
waste siting criteria (310 CMR 16.40).
This permit requirement clearly does not
4-5
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apply to the listed lined landfills. At all
upland sites, site suitability for
construction of a secure landfill would
need to be determined. The siting and
permitting of a new solid waste facility in
the Commonwealth of Massachusetts is a
lengthy process. Initially an application
for the suitability of the site must be
submitted to the Massachusetts Department
of Environmental Protection. The
application must include: 1) documentation
that the selected site meets the suitability
criteria; 2) the engineering design report;
3) the landfill operations and management
plans; and 4) certification that the applicant
has complied with the Massachusetts
Environmental Policy Act. The
application is then reviewed by the DEP
and public hearings are held to obtain
comments from the affected community.
The entire process, including site
investigations, landfill design and
permitting, may require three to five
years. The actual time required for the
permitting of a facility may vary from this
estimate, depending on the complexity of
the site conditions and environmental
constraints, time required by the DEP to
review the documentation and the level of
public concern.
Given the difficulty of siting and
permitting a disposal site, the land-based
options may be more suitable for future
maintenance material.
4.1.2 Direct Impacts
This section describes the direct
environmental impacts associated with the
land-based sites. The impacts include
permanent and temporary loss of federal or
state resources and the permanent
alteration of resources from the existing
conditions to altered conditions after
construction. The impacts discussed in
this section are attributable to the upland
inland and coastal sites only; no direct or
indirect impacts would occur with use of
the lined landfills because the facilities are
currently constructed and operating.
4.1.2.1 Permanent Loss
Both inland sites, Woburn and Wrentham,
have jurisdictional wetland habitat within
their respective footprints. Construction of
a disposal facility would permanently fill
these resources and eliminate their
associated functions (Table 4-1). At
Woburn approximately 1 acre of forested
wetland would be affected, and avoidance
would be very difficult due to the physical
configuration of the site. At Wrentham,
most of the major wetland areas have been
avoided in calculating the usable site
acreage. New information provided by the
DEP, since the DEIR/S, indicates a 15-
acre area containing numerous isolated
wooded wetlands. Avoidance of these
wetlands reduces the available capacity of
the site from the 785,000 cy stated in the
DEIR/S to approximately 525,000 cy. No
permanent loss of jurisdictional wetlands
would occur at Everett or Squantum Point.
At all of the inland and coastal sites,
construction of the disposal facility would
result in the permanent loss of vegetation
and wildlife habitat within the footprint of
the facility. Current conditions at three of
the sites, Squantum Point, Everett, and
Woburn, are moderately to highly
disturbed with predominantly bare or
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.
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artificial substrates and early successional
vegetation. At the fourth site, Wrentham,
the habitat is predominantly undisturbed
forest and shrubland, although sand and
gravel operations have left the southern tip
of the site highly disturbed. Wildlife
habitat values are correspondingly low at
Squantum Point, Everett and Woburn,
although at Squantum Point, wildlife
habitat value is relatively higher hi spite of
the site's disturbed condition because it
provides open land on an urbanized
harbor. At Wrentham, wildlife habitat
values are considerably higher due to the
site's large size and relatively low degree
of disturbance.
avoid the site during disposal activities, but
could return upon closure.
At the inland land-based sites, temporary
impacts due to odor and noise may occur
along trucking routes that pass sensitive
receptors such as residential areas and
schools. These impacts would likely be
more obvious in the suburban roads of
Woburn because at Wrentham, Green
Road and Route 1A, are already used by
quarry and asphalt trucks. Temporary
odor impacts would cease upon completion
of the silt disposal. Noise impacts would
continue through capping and closure of
the facility.
4.1.2.2 Temporary Loss
Temporary loss is presumed to be a less
serious impact than permanent loss because
the functions attributed to the lost resource
would be regained. In the case of wetland
habitat, the Federal "no net loss" policy
would be maintained. Temporary losses at
the land-based sites would include channel
dredging hi the shallow subtidal areas of
Squantum Point and Everett to allow barge
access (Table 4-1). The maximum depth
of dredging is anticipated not to exceed 6-8
feet, therefore the benthic community that
re-established after dredging should be
very similar in composition and structure
to the original community. Also, at these
two coastal sites, the use of the surround-
ing mudflats and beaches by shorebirds
and waterfowl could be disrupted by on-
site activities; however use should resume
upon closure of the facility. The common
terns observed in courtship on the
abandoned pier at Everett will also likely
4.1.2.3 Permanent Alteration
At Squantum Point, permanent habitat
alteration would occur with channel
dredging for barge access in the 0.3-acre
intertidal zone where mudflat, and possibly
salt marsh, would be converted to subtidal
land. This would result in changing the
functions and values of the area from
intertidal (primarily migratory bird resting
and feeding habitat, intertidal productivity,
water quality treatment and shoreline
stability) to those of subtidal areas
(primarily shellfish and finfish feeding and
breeding habitats). This alteration could
be mitigated at closure by restoring
intertidal conditions to the affected areas.
4.1.3 Indirect Impacts
The primary indirect impacts would
potentially occur at Wrentham, and include
risk to a Zone II aquifer, forest
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fragmentation, and loss of tax base if a
proposed industrial subdivision were
precluded. The Zone n aquifer lies under
the northernmost portion of the site.
Avoiding the aquifer, in combination with
avoidance of the wetlands (see Permanent
Losses section) further reduces the capacity
of the Wrentham site to 451,000 cy.
Forest fragmentation would result because
most of the portion of the site proposed for
the containment facility (excluding the
southernmost portion which is disturbed) is
currently part of a large block of
undeveloped shrub/forested land. Upon
site closure, the facility would be capped
and could be managed as natural habitat,
but because penetrating roots are usually
discouraged on permanent caps, it is
unlikely that forested habitat would be
allowed to develop. Loss of potential tax
base to the Town of Wrentham could
result if an industrial subdivision currently
proposed at the northern end of the parcel
" were precluded by development of the
disposal facility. However, because this
portion of the parcel overlies the Zone II
aquifer, and would likely be avoided by
BHNEP, the two projects could potentially
be developed concurrently.
At Squantum Point, indirect impacts would
include a potential conflict with a proposed
MDC park at the site. Park development
plans could be feasible after closure and
capping of the disposal facility.
Other indirect impacts that are common to
all four land-based sites are noise and odor
impacts to sensitive receptors, primarily
residences, surrounding the sites. Noise
could be partially mitigated by limiting
operations to hours of the day that
minimize the impact. Potential odor
controls include use of chemical agents to
mask or seal odors, or the application of a
daily cover material. The need for daily
cover could substantially reduce the
capacity of the facility for silt disposal.
4.1.4 Identification of the Least
Environmentally Damaging Land-Based
Alternatives
Impacts to the lined landfills and the four
upland alternatives evaluated herein are
summarized in Table 4-1. The three lined
landfills are treated together and obviously
have the fewest environmental impacts
because the facilities have already been
constructed and are equipped to control
any potential operational impacts such as
odor or noise. Primary differences among
the upland sites include impacts to
freshwater wetlands (Woburn) and
intertidal wetlands (Squantum Point),
traffic and neighborhood issues, and
impacts to non-wetland habitats. Based on
these issues, the sites would be ranked
(from least to greatest impact):
• Lined Landfills
•. Everett
• Wrentham
• Woburn
• Squantum Point
These sites are subjected to the
practicability screening in Section 4.4.
4.2 AQUATIC SITES
The short-list of aquatic sites presented hi
Chapter 3 includes sites from several
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categories. These sites are shown on
Figure 4-1.
Shoreline
Amstar
Cabot Paint
Little Mystic Channel
Mystic Piers
Reserved Channel
Revere Sugar
Subaqueous Depressions
Subaqueous B
Subaqueous E
Borrow Pits
Meisburger 2
Meisburger 7
Spectacle Island CAD
In-Channel Sites
Chelsea Creek
Inner Confluence
Mystic River
ExisringLDjsposal Sites
Boston Lightship
The proposed disposal scenario would be
unique to each type of site. Shoreline sites
are aquatic areas contiguous to the Boston
Harbor shoreline. The existing site
boundaries are defined by man-made
bulkheads and walls, with one side
exposed to the Harbor. There are two fill
alternatives proposed for the Amstar,
Cabot Paint, Little Mystic Channel, Mystic
Piers and Revere Sugar sites. The partial-
fill alternative would result in a final
elevation, including cap, of mean low
water. The fast land alternative would
result in filling to the elevation of the
adjacent land. For both alternatives, a
bulkhead would be constructed to isolate
the site from the Harbor during disposal.
The bulkhead would remain hi place after
disposal hi the fast land alternative but be
cut off at MLW after the cap was secured
for the partial-fill alternative.
The alternative fill scenarios identified for
the Reserved Channel involve partially
filling different areas of the Channel
upstream of the Summer Street bridge.
Fill could be placed either hi the entire
area west of Summer Street or in the
western end of that area. In either case,
the western end would be filled to a final
grade of +9 ft. MLW, a suitable elevation
for establishing salt marsh vegetation. The
eastern portion would be filled to a final
elevation of -6 ft. MLW. Both areas
would require bulkheading during disposal.
Use of the Outer Harbor Subaqueous sites
B and E would rely on existing
bathymetric conditions to keep disposed
sediments in place. Sediments would be
transported by bottom-dumping scow.
After disposal of silt is complete, the area
would be capped by depositing granular
material over the sediments. The final
elevation of each site would be no higher
than the surrounding conditions.
Construction of any of the borrow pit
sites, Meisburger 2, Meisburger 7 or
Spectacle Island CAD, would require
dredging existing sediments to create a pit
in which to bury the silts from the BHNIP.
In each case, a portion of the surface
material present at the site would be
retained to be placed over the BHNIP silts
to isolate them from the water column and
restore the substrate to preexisting
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conditions. Sediments dredged from the
Meisburger sites would likely be suitable
for beneficial uses such as beach
nourishment or construction aggregate.
In-channel disposal would occur within
portions of the footprint of the channels to
be dredged under the BHNIP. These areas
would be deepened by dredging additional
parent material. Because of the character
of the subsurface sediments, the additional
deepening can be done in confined cells.
Individual cells would be filled soon after
construction and capped with granular
material soon after being filled. The extra
parent material that would be dredged
would be disposed in the same manner as
the parent material originating from the
planned dredging project.
Disposal at Boston Lightship (BLS) would
require no site preparation. Barges would
dump silt at a designated location resulting
in a mound. The mound would be capped
at the conclusion of the disposal activities.
4.2.1 Direct Impacts
Direct impacts could include the permanent
or temporary loss, or permanent alteration,
of aquatic habitat in the footprint of the
disposal operation. The 404 (b)(l)
guidelines direct the project proponent
avoid or minimize the loss of aquatic
habitat. The Corps and EPA have also
established a Memorandum of Agreement
stipulating a goal of no net loss of wetland
values and functions.
4.2.1.1 Permanent Loss [404 (b)(l)
issues]
Of the aquatic disposal alternatives
evaluated for the BHNIP, any site where
disposal of dredged material would raise
the elevation of the site above the high
water elevation would result in a
permanent loss of aquatic habitat and the
associated functions. This has been
proposed only for one scenario involving
the shoreline sites, i.e. creation of fast
land. Because each of these sites abuts a
filled shoreline, disposal would eliminate
both subtidal and intertidal habitat. The
subtidal habitat at these sites is composed
primarily of soft, fine-grained sediments,
whereas the intertidal habitat consists
primarily of vertical bulkheading,
composed of wood, steel, concrete, or
rock. Selection of one of the shoreline
sites for fill to fast land could be contrary
to the goal of avoidance of loss of aquatic
habitat, particularly if other sites were
available and practicable and would not
result in permanent loss of aquatic habitat.
Disregarding the issue of site capacity and
the ability to meet the disposal needs of the
BHNIP, the aquatic sites differ with
respect to the level of direct impacts. The
first level of comparison is the permanency
of the impacts. Filling the aquatic
shoreline sites (Amstar, Cabot Paint, Little
Mystic Channel, Mystic Piers, or Revere
Sugar) to fast land would result in the
permanent loss of aquatic habitat (Table 4-
2.). Although these areas were found to
have relatively low capacity for bottom
habitat productivity, and their individual
footprints are small, federal regulatory
concerns focus on the fact that Boston
Harbor has experienced thousands of acres
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of fill over the last two centuries. If this
design was selected for disposal of the
BHNIP sediments, it would require the
filling of all the identified aquatic shoreline
sites for a total permanent loss of 30.5
acres of subtidal estuarine habitat.
Additional disposal alternatives would also
be necessary because those sites could not
hold all the project's silts. Individual sites
range in size from 2.7 (Mystic Piers) to 15
(Little Mystic Channel) acres (Table 4-2).
4.2.1.2 Temporary Loss
Temporary loss of habitat is presumed to
be a less serious impact than permanent
loss because it minimizes the impact to
aquatic habitat function. Habitat function
in the footprint of disposal activities could
be temporarily disrupted or lost under
several scenarios. This concept assumes
that it is possible to restore the affected
substrate to (or near) its original character,
so that biological activities could be re-
established after disposal. This approach
is proposed for the borrow pit sites, where
material removed to create the pit would
be stored adjacent to the pit, until
construction of the final cap or closure of
the site. This method ensures that both
the physical and chemical composition of
the surface sediments are restored.
Construction of a borrow pit could also
cause a temporary impact on an area
adjacent to the pit because the cap material
would likely be stored on the sea floor
rather than on a barge. In the case of the
offshore sites, dredging of the pits would
be most easily accomplished with a hopper
dredge, sidecasting material intended for
use as a cap onto the adjacent substrate.
Therefore, the adjacent substrate habitat
would also be temporarily impacted.
Storage of the cap sediments underwater,
in the same conditions as the disposal site,
could be beneficial to future recruitment of
organisms to the cap.
4.2.1.3 Permanent Alteration
In some cases, although there would be no
permanent loss of aquatic habitat, use of a
site for disposal of dredged materials could
alter the substrate in either of two ways,
through a change in depth or a change hi
substrate character. At sites where little or
no site preparation (e.g., the subaqueous
sites in the Outer Harbor, and the
shoreline sites under the partial fill
scenario) would be required, disposal
would reduce the site depth. The
distribution of benthic organisms is not
related strictly to depth, but more closely
to physical features such as intertidal
exposure, substrate texture (grain size) and
current or wave regime. However, motile
organisms associated with the substrate
(e.g., whiter flounder) seek out different
depth strata over the course of their life
cycles or in response to seasonal changes
hi environmental conditions. For instance,
during periods of warm water
temperatures, estuarine fish move into
deeper areas to find cooler temperatures.
This behavior is more prevalent hi adult,
rather than juvenile, fish.
Change in the physical or chemical
character of the substrate is the other
alteration that could occur. Sediment grain
size distribution can have a significant
effect on the distribution of benthic species
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(Rhoads & Germane 1982), so a radical
deviation from the conditions present at a
disposal site could affect recruitment of
benthos following capping. Presence of
organics or contaminants in sediments
could restrict the character of the benthic
community to stress-tolerant, opportunistic
species. The purpose of the cap at any of
the potential aquatic disposal sites,
however, would be to isolate these
contaminated sediments from the
surrounding environment. Any capping
material used would need to meet all
regulatory standards for unconfined, open
water disposal and would, hi fact, be of
the same or better chemical quality than
the present sediments at any disposal site.
Therefore, the chemical quality of the
sediment at the disposal site would not be
compromised when capped.
Sites where capping could alter the
physical character of the sediments include
the in-channel sites, the Outer Harbor
subaqueous sites and the partial-fill
shoreline sites. The resulting chemical
quality of the cap could be an
improvement over existing site conditions
at any of the in-harbor sites (e.g., in-
channel or shoreline sites), although
physical character could be different.
Capping the dredged material with
substrate similar to the existing substrate
(if available) would increase the chance of
returning populations to pre-dredge
conditions. However, there is good reason
to modify the existing substrate if the
proposed substrate meets or exceeds the
habitat productivity and diversity potential
of the areas as they exist at present.
Direct impacts at all the other sites, as
well as the partial fill scenario for the
shoreline sites, would be temporary (Table
4-2). The sites can be compared on
several criteria:
• the size of the impact area;
• physical changes to the site
that could affect its functional
value;
• the likelihood and rate that the
benthic community, as an
indicator of the functional
value of the habitat, would
return to pre-project conditions
(a measure of the longevity of
the temporary impacts)
A. Size of Impact
The comparison of impact size is
appropriate only when placed hi the
context of whether the site has the capacity
to fill the project's disposal needs. Even if
all shoreline sites were partially filled for
the BHNIP, their combined capacity would
fall short of the disposal capacity needed.
The total footprint altered would be about
47 acres, comparable to the footprint of
the Spectacle Island CAD, which was
designed to provide disposal capacity for
the full volume of silt to be generated from
the BHNIP. The In-channel alternatives
(the Inner Confluence hi combination with
the Mystic and Chelsea Rivers) would be
sufficient for all the BHNIP silts. Their
combined footprint would be about 116
acres, although at any given time, the
disturbed working footprint would be less
than about 15 acres (two to six cells). In-
channel disposal would occur only in the
footprint of the channel deepening.
Therefore, the in-channel alternative is the
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only one that will not increase the impact
area of the project beyond that of the
dredging. Subaqueous B (83 acres) and E
(79 acres) would impact similar footprints,
but, even combined, would not provide the
capacity needed for all the BHNIP. Each
of the offshore sites would have sufficient
capacity for the BHNIP sediments.
Estimated impact footprints at these sites
would range from about 86 acres
(Meisburger 2) to 121 acres (Meisburger
7) (Table 4-2).
Based on footprint of impact alone, the
Spectacle. Island CAD would appear to
result in substantially lower total impact
than any of the other sites, except in-
channel disposal. However, the dredging
and disposal sequence, as it relates to the
portion of the site impacted at any one
tune, must be considered. Geological
conditions at Spectacle Island make it
unlikely that this site could be developed
in small consecutive cells, whereas the
Meisburger and in-channel sites could be.
In addition, this assessment must be
qualified by evaluating exactly what the
impact entails. Specifically, these include
whether there are permanent alterations in
habitat conditions, and the likelihood that
the subtidal community (as an indicator of
habitat value) would return to pre-project
or improved conditions.
B. Physical Changes
Many of the sites evaluated would require
permanent alterations in depth. Under the
partial fill scenario, five of the shoreline
sites would require filling subtidal areas to
intertidal elevations. The sixth shoreline
site, Reserved Channel, would be filled in
a gradient from shallow subtidal to high
intertidal. This addition of atmospheric
exposure could have a substantial effect on
both the structure and abundance of the
benthic community, in the high intertidal
zone, although this would not necessarily
be a deleterious impact. Intertidal habitat
hi Boston Harbor, once plentiful, is now
primarily restricted to vertical faces of
man-made materials. Few soft substrate
intertidal flats remain hi the Inner Harbor.
Such habitats provide refuge and feeding
habitat for juvenile finfish, as well as
permanent habitat for sessile species such
as soft-shell clams. Therefore, the partial
fill scenarios could provide a beneficial
increase in habitat diversity (particularly
for finfish) in Boston Harbor.
Use of the Subaqueous B and E sites
would also require raising the elevation of
the substrate such that water depths would
be shallower than existing conditions. In
these cases, this could prove detrimental to
finfish. In a shallow water environment,
deeper areas are used to avoid temperature
extremes. This is particularly true in the
summer hi Boston Harbor. Therefore,
although the benthic impacts would cease
after closure of either of these sites,
impacts to finfish could be permanent.
Depth changes would also occur at Boston
Lightship. In this case, the disposed
dredged material and cap would form a
mound on the substrate. Because the site
is in deep water (150 ft), the height of the
mound would be insignificant to
surrounding
substrate. It is unlikely that the height of
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the mound would affect finfish utilization
of the site.
Substrate character could be permanently
altered at some of the sites, including the
shoreline sites, the in-channel sites,
Subaqueous B, Subaqueous E and Boston
Lightship. Closure or isolation of the
disposed dredged materials at these sites
would require capping with sediments not
native to the disposal site. The three
borrow pit areas, Spectacle Island CAD,
Meisburger 2 and Meisburger 7, would
each be capped using surface sediments
from the excavated site.
The existing sediments within the shoreline
sites are predominantly silty, and evidence
suggests that they contain elevated
concentrations of various organic and
inorganic contaminants. The partial fill
scenario would cover these sediments with
dredged materials, isolating them from the
Boston Harbor ecosystem hi permanently.
Dredged materials disposed at these sites
would have to be confined to prevent their
redistribution in the Harbor. A sand or
clay cap would be used for this purpose.
Sand would be more rapidly colonized by
benthic infauna than would clay. Neither
sediment would be particularly susceptible
to adsorption of chemicals. Demersal
finfish, especially winter flounder, would
find a sand substrate more attractive than
either silt or clay. Sand would also
provide a more suitable habitat for
Crangon (sand shrimp), an important food
resource for finfish, that has been reported
to occur in the Inner Harbor. These
benefits would decline as silts from other
sources setded out of the water column in
these areas.
Use of a granular cap in the in-channel
sites, or the two subaqueous sites, could be
beneficial to finfish. Because the in-
channel area appears to provide spawning
and juvenile nursery habitat for winter
flounder, this provision of preferred
granular substrate would be especially
beneficial. Those areas requiring armoring
with rock, because of their vulnerability to
vessel traffic, would be of reduced value
to juvenile winter flounder but would
increase benthic diversity which may be
beneficial to other fish. Again, this benefit
would diminish as sediments accumulated
in the channels.
Capping of the disposal mound at Boston
Lightship with sand would provide
substrate similar to the natural conditions.
A clay cap would be structurally different,
and would probably provide a less valuable
habitat than currently exists.
C. Subtidal Community Recovery
The likelihood that the structure of the
bottom (subtidal benthic) community
would re-establish is a function of the pre-
project conditions and the types of
alterations that would be made at the site.
The benthic community at each site was
selected as an identifier of site habitat
quality because the organisms are sessile
(and therefore site-specific) and are an
important energy source for higher trophic
levels. In general, areas that are in
stressed environments prior to use as a
disposal site have benthic communities
adapted to that level of stress. As in the
Inner Harbor, most benthic species in this
type of environment are pioneers; they live
in the surficial layers of the substrate.
They also reproduce frequently (multiple
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generations per year) and prolifically.
Larval development may follow two
strategies within the same species, ie.,
direct (avoiding the dispersion of
planktonic larval development) or
planktonic (allowing initial recruitment to
the area). These characteristics allow
these species to colonize recently disturbed
sediments quickly and to recover from
intermittent stresses. All areas examined
for use as a disposal site for the BHNIP
had some pioneering species in their
benthic communities. However, the
benthos in the Outer Harbor and the
offshore areas had proportionately higher
numbers of later successional stage species
composed of longer-lived, subsurface
dwellers. These later successional
communities take longer to develop and
require a more stable physical and
chemical environment.
The ability of a site to recover its pre-
project bottom productivity can, therefore,
be related to the proportion of pioneering
species comprising the community. Sites
in the Inner Harbor are predominantly
pioneering communities, therefore
recovery would be expected to be the most
rapid. Sites in the Outer Harbor exhibited
a mixture of pioneering and Stage n
benthic species. Therefore, some recovery
would be apparent in the short term, but a
longer period would be required to
complete the recovery. All three offshore
sites supported benthic communities that
were primarily Stage II species with few
pioneering species. These communities
would take the longest to recovery.
4.2.1.4 Summary
Based on all aspects of direct impacts, the
potential aquatic disposal sites are ranked
(from least to greatest impact):
• In-channel
• Shoreline/partial fill
• Spectacle Island CAD, Meisburger
2, Meisburger 7, Boston Lightship
• Subaqueous B, Subaqueous E
• Shoreline/fast-land
The in-channel alternative is ranked as
having the least direct impact because this
alternative would be confined entirely
within the footprint of the navigation
improvement dredging. Also, the
proposed capping would improve the
physio-chemical conditions of the
substrate, and biological recovery would
be expected to be rapid. While partially
filling the shoreline sites would satisfy the
last two concerns, their location outside
the proposed dredge area would result hi
an increase in the total impact area for the
project.
4.2.2 Indirect Impacts
Indirect impacts would encompass those
effects that occurred beyond the boundaries
of the disposal site (and mixing zone) as a
result of the implementation of a particular
disposal scenario. These effects include
changes in water quality, or effects on
marine biota or habitats.
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4.2.2.1 Water Quality Effects
Water quality impacts caused by the
disposal of dredged materials were
examined in several ways. The mixing
zone is of primary regulatory interest
under the Clean Water Act and the Water
Quality Certification Regulations for both
state and federally regulated waters,
although it is not defined quantitatively hi
the regulations. Pollutant-transport and
ADDAMS models were used to identify
mixing zones for the potential disposal
sites. In this analysis, for state-regulated
waters, the mixing zone was identified as
the area outside of which the chronic water
quality standards are met. For sites
outside of state-regulated waters, the
mixing zone was defined as the site
boundary outside of which water quality
standards would be met four hours after a
disposal event, the typical standard used
for open-water disposal sites. For state
water quality requirements, the mixing
zone analysis focussed on the period
immediately following each disposal event.
The more typical water quality condition
for this project is reflected in a scenario of
multiple-day disposal events. Model
results indicated that this scenario would
cause steady state water quality conditions
to be reached after an extended period of
repetitive (daily) disposal events.
Maximum concentrations based on this
scenario were also modelled. Results of
these analyses are detailed hi Appendix F.
Disposal of silty dredged materials in
aquatic systems tends to result hi
dispersion of about 5% of the sediments
away from the point of disposal. Local
hydrodynamics, operational schedules, and
the volumes of material disposed determine
whether repeated disposal events would
result hi an undesirable concentration of
suspended sediments. This effect has been
modelled using a pollutant transport model
based on the ADDAMS model
(STFATES); results are detailed in
Appendix F. There is no regulatory
criterion for Total Suspended Solids (TSS)
against which to compare these results.
However, other dredging projects hi
Boston Harbor have been required,
through permit conditions, to prevent TSS
from exceeding 50 mg/L (including
ambient loads). A criterion of 50 mg/L
was used to determine the TSS mixing
zone for each potential disposal site for the
BHNIP.
Physical handling of dredged materials can
cause some chemical changes, particularly
dissolution of contaminants bound to
sediment particles. This effect is generally
quite limited. Elutriate testing provides an
indication of this effect. Elutriate tests
performed on actual sediment samples
from the channels proposed for dredging
showed that mercury, copper and PCBs
could be released from sediments
descending through the water column at
the disposal site. Concentrations of metal
in addition to naphthalene (a PAH
compound that represents PAHs most
likely to be in the dissolved, as opposed to
particulate, phase), that would result from
the proposed disposal event schedule were
modelled using the pollutant transport
model described for TSS. Resulting
concentrations were added to ambient
concentrations and then compared to
chronic-level water quality criteria (from
USEPA 1986). Of these parameters,
PCBs exhibited the greatest potential to be
released into the water column. Model
4-16
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results indicate that the chronic water
quality criterion for PCBs (0.03 ppb)
would not be exceeded outside the TSS
mixing zone at any aquatic site.
A third potential source of short-term
water quality impacts is loss of sediments
to the water column when the disposed
"mass" of dredged materials encounters the
substrate. The likelihood of sediment
rebound was evaluated using STFATES
(Appendix F). This effect could
conceivably occur during each disposal
event. The primary effect of sediment
rebound would be release of additional silt
into the water column. Model results
indicated that the release of sediments back
into the water column would be negligible.
Comparison of water quality effects among
sites can be made based on the size of the
mixing zone required to meet State
standards for Water Quality Certification.
The state standards require minimization of
the. mixing zone around a dredging or
disposal operation and the avoidance of
impacts to migration routes and other
impacts to resources. Mixing zones for
each of the potential aquatic disposal sites
were identified for total suspended solids
(which represents an absolute load to the
water body) and PCBs (the parameter
whose predicted levels from disposal
alone, in addition to ambient levels, are
closest to the chronic water quality
criterion). For the in-channel locations,
the models also included input of these
parameters from nearby dredging
operations; the only disposal alternative at
which this combined effect could happen.
Mixing zone models assumed disposal
would take place near high tide to avoid
buildup of undesirable constituents (TSS,
PCBs). This schedule restriction would be
part of the dredge management plan.
Because there has been no numerical
standard established for total suspended
solids, a value of 50 mg/L, based on other
recent Harbor dredging projects, has been
used in this analysis as the critical limit for
the mixing zone. The PCB analysis used
the federally-established chronic water
quality criterion of 30 ng/L (0.03 ppb).
In each case, the mixing zone needed to
meet total suspended solids concentration
goals would be larger than for PCBs
(Table 4-3). Under worst-case conditions
(an anticipated 14-day period of 6,000 to
10,000 cy disposal per day), the area
needed for mixing for the in-channel
alternative would range from 12.4 (TSS,
Mystic River) to 30.0 (TSS, Chelsea
River) acres. In each case, the shape of
the mixing zone would reflect tidal current
characteristics. In general, the shape of
the mixing zone would be oriented along
the predominant ebb tide direction. Width
would be controlled by current velocity.
Mixing zones hi the Inner Harbor areas
w.ould be elongated, while those in the
Outer Harbor, reflecting the more open
conditions, would be more square. This
aspect is important in examining -potential
impacts in the Inner Harbor. Mixing
zones in the Outer Harbor sites (7.7 - 10.4
acres) are similar to the offshore (about 10
acres) sites.
Typically, at open water disposal sites, the
boundaries of the mixing zone are defined
as the boundaries of the site. In waters
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under federal (Sec. 103) jurisdiction, the
acute water quality criteria must be met
outside the disposal site (i.e., the mixing
zone) within four hours following a
disposal event. The ADDAMS model
results indicated that this condition could
be met at the Meisburger 2 and 7 sites and
the Boston Lightship site. The estimated
footprints of these sites range from 86 to
121 acres; and the mixing zone would not
extent beyond this area.
Modeling of repetitive disposal events
(Appendix F) indicated that none of the
aquatic disposal sites would experience
chronic water quality violations over the
duration of the disposal. Disposal
activities at the shoreline sites, whether
partially or totally filled, would not affect
water quality during the construction
phase.
The modeling results suggest that there
would be spatial (size) differences hi the
mixing zones at each site, but that
shoreline resources should not be exposed
to contaminant levels that exceed chronic
water quality criteria. It also appears that
while some portion of the waterway would
be disturbed during the disposal events,
blockages of anadromous fish migratory
routes would not likely be a problem.
Comparing sites, based on the size of the
mixing zone, would result in the following
ranking (smallest to largest mixing zone):
• Spectacle Island
• Subaqueous E
• Meisburger 2, Meisburger 7
• Boston Lightship, Subaqueous B
• Mystic River
• Inner Confluence
• Chelsea River
4.2.2.2 Site Stability
The use of a site for disposal of dredged
materials could have long-term impacts if
the prevailing hydrodynamics (especially
bottom currents) caused resuspension of
the sediments. Normal tidal currents,
wind or storm generated waves and vessel
activity (propeller wash) can all affect the
magnitude of bottom currents. The
predominance of each of these factors
varies among the sites being evaluated for
disposal of dredged materials. Bottom
currents in excess of 20 cm/sec (0.7 ft/sec)
can resuspend and transport noncohesive
silt (Gross, 1977). The cohesiveness of
Boston Harbor surface sediments suggests
that they would reach the bottom in
clumps, and might require a slightly higher
bottom current to induce resuspension (in
the 30-50-cm/sec or to 1.6- ft/sec range).
This effect was examined using the
LTFATES model developed by the US
Army Corps of Engineers Waterways
Experiment Station (see Appendix F for
details). Results were used to predict the
likelihood of long-term transport of
dredged material from the disposal site,
and therefore the resulting need for a cap
on the site to prevent such transport, and
the likelihood that the cap would be
successful.
Factors affecting site stability (as presented
in Attachment 1 and Appendix F) are
summarized in Table 4-4. The seriousness
of each source of impact is a function of
its frequency and magnitude, the likelihood
of catastrophic failure, and the types of
mitigative actions during and after
construction that would be feasible at each
site. Site design is also an important
factor in determining site stability. This
4-18
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issue was evaluated for construction and
post-construction phases for each site.
A. Project construction
During construction, only the shoreline
fast-land and partial fill scenarios would be
completely protected from potentially
erosional forces because the bulkhead
would isolate these areas from the Harbor.
The sites that would be exposed to erosion
from tidal currents would be at the greatest
risk because of the frequency (as often as
once to twice daily) and breadth of these
forces. Propeller wash effects, on the
other hand, could occur as frequently as
one to several times per day, but in limited
areas. Storm events would generally be of
lower frequency (variable among sites
from once to many tunes per year in
susceptible areas) and therefore could be
dealt with on a case-by-case basis. While
a cap could be protected with armoring, in
the long term it would generally be
difficult to protect the site completely
during construction.
Subaqueous B would be particularly
vulnerable because it could be disturbed by
tidal currents, ship passage, and one-year
storm events. Both Subaqueous E and
Spectacle Island CAD would be exposed to
tidal currents and storm and wind
generated waves. In fact, Spectacle Island
CAD could be affected by storms much
more frequently than once per year.
Additional studies would be necessary to
confirm the severity of this effect and to
determine whether engineering solutions
would be available. The three offshore
sites, Meisburger 2, Meisburger 7 and
Boston Lightship, would be susceptible to
disturbance by storms (but not to other
factors such as propeller wash) during
construction. The potential to construct
Meisburger 2 or 7 in cells would enhance
the ability to implement protective
measures such as interim capping to secure
the site in response to predicted storm
events. This would be less easily
accomplished at Boston Lightship because
the entire disposal mound would have to
be secured, although the greater water
depths at BLS indicate that a more severe,
and less frequent, storm would be
necessary to affect this site. Portions of
the in-channel locations could be exposed
to vessel-generated currents routinely.
This situation could be minimized by
construction management such as
scheduling the use of the most vulnerable
areas during periods of lowest ship traffic
(i.e., avoid periods when liquified natural
gas (LNG) tankers are expected),
implementing navigational restrictions, and
providing physical barriers such as silt
curtains around the disposal site. Stability
of the shoreline sites would not be affected
by these factors during construction.
B. Post-Construction Cap Failure
Because of its mound configuration and
frequency of potential weather events
capable of affecting it, the Boston
Lightship would be at a relatively high risk
of failure. The higher frequency of
weather events that could affect Spectacle
Island CAD would place it at a similarly
high risk for failure. Although weather
disturbances would be less frequent at
Subaqueous B and E, the frequency of
4-19
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potential disturbance by tidal currents in
addition to the storm currents would
increase the risk of site failure. Either site
could be armored after closure if post-
closure monitoring showed it was
warranted.
The integrity of the partial fill shoreline
sites would be dependent on being able to
maintain sufficient geotechnical strength to
prevent slumping after the bulkhead was
cut off at MLW. While the slope would
not be great at these sites, the disposed
dredged materials would have a high water
content that would initially be unstable.
Stability would improve as the sediments
became consolidated, although this could
take a period of years. With the exception
of the Reserved Channel, each of the
shoreline sites is adjacent to a berth or
channel and could be exposed to travelling
or turning vessels. This would not be a
problem for the fast land scenario.
The ability to construct the Meisburger 2
and 7 sites in multiple cells would reduce
the risk of catastrophic failure during and
after construction. Therefore, these sites
are considered to be at lower risk of
failure despite the potential for weather-
related bottom currents to affect the
substrate more than once a year.
Vessel traffic is the only factor that would
be likely to disturb the substrate in the in-
channel disposal sites. Because areas
vulnerable to disturbance by propeller
wash can be identified and armored, the
in-channel areas face a lower risk of
failure than other sites.
C. Summary
The risk of site failure differs among sites
and between the construction and post-
construction phases. During construction,
the sites are ranked (from least to greatest
risk):
• Shoreline-Fast Land or Partial Fill
• In-channel
• Meisburger 2, Meisburger 7
• Boston Lightship
• Subaqueous E
• Subaqueous B, Spectacle Island
CAD
The shoreline sites would have the lowest
risk of site failure during construction
because the bulkhead would prevent
exposure to erosive currents emanating
from any source. In-channel locations
were considered to have the next lowest
risk because the only potential source of
strong bottom currents (vessel traffic)
would be limited to identifiable areas.
Construction management techniques,
including limiting the size of the exposed
work face, to limit the period of exposure,
can be implemented to minimize impacts.
The potential for post-construction failure
(i.e., cap failure and release of disposed
silts to the environment) would rank the
sites (from least to greatest risk):
• Shoreline-Fast Land
• In-channel
• Meisburger 2, Meisburger 7
• Shoreline-Partial Fill
• Subaqueous E
• Subaqueous B
• Spectacle Island CAD, Boston
Lightship
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The shoreline (fast-land) alternatives would
experience the lowest risk of post-
construction failure beacuse the bulkhead
would protect the disposed sediments from
the influence of all currents. Because the
magnitude of the vessel traffic impacts in
the Inner Harbor is more predictable than
storm effects in other locations, protective
measures are more easily identifiable and
implementable for the in-channel locations
than other sites; thus is ranked as having
the record lowest risk.
4.2.2.3 Downstream Impacts
Use of aquatic disposal sites could impact
downstream resources during site
preparation, during disposal or after
disposal. This analysis addresses the
concerns of impacts during active site use
and the potential impacts of post-
construction cap failure at the site.
A primary mechanism for these impacts is
the hydrodynamics of the disposal site.
Because tidal currents predominate over
other normal currents at all of the potential
aquatic disposal sites for the BHNIP,
"downstream" includes the areas
influenced by either flood or ebb tides in
relation to the disposal site. As indicated
in the preceding section, hydrodynamics
govern whether material (suspended
sediments, including bound or dissolved
contaminants) could be transported from
the disposal site. Modeling done to
evaluate impacts to water quality provides
insight into the likelihood that biological
resources and commercial users of water in
the sphere of influence of the disposal site
would be affected by use of the site.
Impacts arising during site preparation or
disposal would constitute short-term
effects. Impacts arising after closure of
the disposal site would constitute long-term
impacts.
A. TSS Concentrations
Environmental concerns about dredging
and aquatic disposal events include the
potential for increased total suspended
solids (TSS) to interfere with the vital
functions of aquatic organisms (e.g.,
clogging of gills) as well as seasonal
movements (e.g., fish migrations). There
is also concern that if concentrations of
any contaminants released from the
sediments exceeded chronic-level water
quality criteria, organisms exposed to those
waters could experience sublethal or toxic
effects. Because they are sessile, benthic
organisms would be at a greater immediate
risk of this exposure than motile finfish.
The distribution of TSS around the
disposal site is a function of both local
hydrodynamics and the settling velocity of
the suspended particles. Silt settles, hi a
static environment, at a rate of 0.01 ft/sec
(0.3 cm/sec). Review of the STFATES
model output can, therefore, provide an
estimate of the areas most likely to
experience sedimentation of the dredged
material escaping the disposal site during
descent. Excessive quantities of settling
silt could smother sessile organisms such
as soft-shell clams and attached (demersal
adhesive) eggs of finfish species such as
winter flounder. Confined silts would also
return those contaminants adsorbed to the
sediment particles to the local
4-21
flF
-------
environment. Depending on the quality of
the existing environment, this could
increase the potential for contaminant
uptake through dermal contact (e.g.,
winter flounder) or ingestion (by any
benthic feeding species) or, alternatively,
keep conditions or the level of risk the
same if surrounding habitats reflect
degraded sediment quality.
Downstream resources of concern can be
categorized into two groups: biotic and
human use. Based on site-specific
investigations (see Attachment I), five
biotic resources (anadromous fish, winter
flounder, lobster, soft-shell clams and
benthos) were identified among the 15
potential aquatic disposal sites. Three
human uses (fishing grounds, water intake
and swimming areas) were identified.
Each potential disposal site was evaluated
in terms of whether its use could affect
any of these resources either during project
construction or as the result of post-
construction cap failure (Table 4-5). The
silt dispersal from the site during each
disposal event (vagrant silt) would be the
primary source of these potential impacts.
Anadromous fish passage through the
Inner Harbor could be affected by
degradation of water quality, in particular
increased suspended solids (TSS). Typical
disposal operations in the In-channel sites
would cause areas of temporarily elevated
TSS, but these areas would extend only
part way across the entire width of the
channel. Therefore, it is unlikely that
disposal would interfere with passage of
anadromous fish through the Mystic River.
B. Project Construction
With the exception of the shoreline sites,
only sediments deposited downstream
would be detectable immediately adjacent
to any disposal site during construction.
Because all disposal at the shoreline sites
would be behind bulkheads, shoreline sites
would be unlikely to have any definable
effect on downstream resources during
construction.
The areas affected during each disposal
event at all other sites would generally be
directly seaward of the barge, assuming
that disposal was restricted to periods
around high tide to optimize the mixing
zone size (see preceding section). The
magnitude of dredging in the BHNIP and
the design of each disposal site would
necessitate frequent repositioning of the
barge within the site, thereby reducing the
likelihood that any specific downstream
area would be subject to repeated
sedimentation. Simple geometry dictates
that the larger the footprint of the disposal
site, the less frequently vagrant silt would
settle outside the site boundaries. In the
in-channel alternative, the sediments
settling downstream of the disposal site
would be similar to the existing sediments.
Excessive siltation could increase mortality
of organisms on the substrate, including
winter flounder eggs in an area about 1.1
acres in size adjacent to each disposal cell.
Site configuration determines, however,
that the area downstream of most disposal
cells, except those in the Inner Confluence,
would be impacted either by the dredging
or disposal aspects of the BHNIP.
Therefore, downstream sedimentation
would not expand the impact footprint of
this alternative by a substantial amount.
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Potential disposal sites located in the Outer
Harbor or offshore would not be adjacent
to areas otherwise impacted by the
BHNIP. Therefore, any downstream
sedimentation outside the disposal area
would expand the impact footprint of the
particular disposal alternative. In addition,
sediments of the Outer Harbor and
offshore sites contain lower levels of
contaminants than those dredged from the
Inner Harbor. Disposal at any of the Outer
Harbor sites would cause sedimentation on
Ampelisca beds, indirectly affecting winter
flounder feeding habitat. The smaller
footprint of Spectacle Island CAD would
allow a relatively larger proportion of the
vagrant silt to settle outside the site
boundaries than either Subaqueous B or E.
Sedimentation outside the boundaries of
the Meisburger 2 or 7 or Boston Lightship
sites could affect Stage n benthic
communities and the groundfish and
lobsters that they support. As with the
Outer Harbor sites, the smaller the
footprint of the disposal site, the more
likely vagrant silt would be to settle
outside the boundaries. Therefore,
Meisburger 2 would be likely to affect a
larger area outside its direct impact
footprint than either Meisburger 7 or
Boston Lightship.
C. Post-Construction Cap Failure
The preceding section on site stability
addressed the factors that could influence
cap failure at each disposal site. The
severity of cap failure is a function of the
likelihood that it could occur and the
resources that could be affected if it did
occur.
Using these criteria, the shoreline sites and
the in-channel sites would have the lowest
potential impact from post-construction site
failure. Vessel activities would be the
most likely cause of loss of site integrity.
However, analysis of traffic patterns has
been used to identify areas vulnerable to
disturbance so that additional protective
measures could be implemented (i.e.,
"armoring" of the substrate with project
rock material). While the dispersal of
disposed dredged materials from these sites
should be avoided, it would not change the
character of the downstream areas
substantially.
The three potential disposal sites in the
Outer Harbor would face a relatively high
risk of cap failure after construction.
Each, and particularly the Spectacle Island
CAD, would be vulnerable to bottom
currents generated by high-frequency (one-
year or less return period) weather events.
In addition, both Subaqueous B and E
could be disturbed by normal tidal
currents. Dispersal of BHNIP sediments
disposed in any of these Outer Harbor sites
into other areas of the Outer Harbor could
have deleterious impacts on several
biological or human use resources by
introducing contaminant-bearing sediments
into an area of improving environmental
quality.
Because of their greater depths, the three
offshore sites would have a reduced
potential of experiencing cap failure than
the Outer Harbor sites, although they
could be affected by storm events. Like
the Outer Harbor, however, release of
BHNIP sediments from these disposal sites
would introduce them into an area of
4-23
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higher sediment quality. The biological
resources that are present at these sites
reflect the physical and chemical quality of
the sediments, and would, therefore, be
more severely affected by contact with
contaminated sediments than in the Inner
Harbor.
D. Summary
Project construction would have limited
impacts on downstream resources. The
sites could be ranked into two categories
under this effect (from least to greatest
effect):
• all Inner Harbor locations
• all Outer Harbor and offshore
locations
This ranking reflects the same rationale as
the ranking- for site stability with the
additional factor that biota in the Inner
Harbor are already adapted to the quality
of fixe sediments proposed for disposal.
Post-construction cap failure, hi which
project sediments were released into the
local environment, could have broader
impacts that would be more distinct among
sites. This evaluation ranked the sites
from least to greatest effect:
• In-channel, Shoreline - Fast-Land,
Shoreline - Partial Fill
• Meisburger 2, Meisburger 7,
Boston Lightship
• Subaqueous B
• Subaqueous E, Spectacle Island
CAD
Again, this ranking reflects the rationale
described for site stability and the exisitng
character of the biota at the potential
disposal sites.
4.2.2.4 Biological Exposure Potential
Exposure of organisms to contaminants,
associated with (or dissociated from) the
dredged materials disposed at any of the
potential disposal sites, could occur
through either water column or benthic
routes. Exposure could occur within or
beyond the disposal site boundaries,
depending on site characteristics. Data
from elutriate, toxicity and bioaccumula-
tion testing were used in conjunction with
pollutant transport modeling to evaluate the
relative magnitude of these effects.
Application of these results to each site
must take into account the quality of the
environmental conditions at or adjacent to
the disposal site.
A. Water Column Exposure
Water column exposure is a function of
areal extent, duration of exposure and
contaminant load. A simple approach to
evaluating water column exposure is an
extension of the pollutant transport models
described in the preceding section and
applying these results to species of concern
for each disposal site. The focus would be
primarily on pelagic and suspension-
feeding species. Because of the transient
behavior of both water column biota and
constituents released into the water column
during the disposal process, the potential
exposure would be limited. Although
demersal finfish species and benthic
4-24
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surface deposit-feeding species would also
be exposed to the water column, direct
contact with contaminants in the substrate
is likely of greater concern for these
species.
Disposal of dredged materials through the
water column is not expected to result hi
violations of chronic water quality criteria
outside the mixing zone, regardless of the
location of the disposal site. While there
are differences hi the size of the mixing
zone for each site, differences among the
sites, hi terms of exposure of pelagic
organisms to contaminants outside these
zones, would not be expected.
B. Substrate Exposure
Exposure of bottom-dwelling (benthic)
organisms can be viewed as a simple
function of footprint of the disposal site,
exposure duration and contaminant load
(relative to existing conditions). Although
population data are available for benthic
communities, use of individual sites by
finfish and other motile species is more
difficult to quantify because many species
exhibit both lifestage, seasonal and small-
scale spatial differences in distribution.
There are no regulatory criteria currently
in place against which to evaluate the
sediment concentrations.
The potential for toxicity and
bioaccumulation of contaminants caused by
exposure to the BHNIP sediments was
evaluated for the DEIR/S (Appendix C of
DEIR/S). Exposure to both berth and
channel sediments resulted in increased
mortality of the sensitive test species,
Ampelisca abdita (amphipod) whereas both
Macoma nasuta (clam) and Nereis virens
(polychaete) exhibited no signs of
increased mortality. By extension, then, it
would be expected that if disposed
sediments were left exposed, sensitive
species (e.g. Ampelisca abdita) would be
unable to colonize them, whereas
potentially less sensitive (e.g. polychaetes
and clams) species might. The COE/EPA
tests were run with adult organisms., not
larvae or juveniles, which are often more
sensitive lifestages. These results are not
completely representative of the actual
environmental effects of the sediments, as
subtidal areas in the Inner Harbor do
support a variety of benthic infaunal
species, occasionally including sensitive
taxa such as Ampelisca.
Bioaccumulation was measured hi clams
and polychaetes. Test results indicated
that benthic organisms that colonized
exposed sediments dredged from berths
would be likely to bioaccumulate metals
(lead and mercury) and organic
contaminants (PCBs and 12 of 16 priority
pollutant PAHs) from the sediments,
providing a route for ingestion by demer-
sally-feeding finfish and epibenthic
invertebrates. Exposure to channel
sediments, however, would likely result hi
bioaccumulation of cadmium, chromium or
lead, but not organics, by deposit feeders.
A similar analysis could be applied to
downstream areas that would be expected
to experience sedimentation of silts
dispersed during the disposal events. The
STFATES models were used to predict
downstream areas that would experience
sedimentation of the vagrant silt (i.e., that
4-25
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lost to the water column during a disposal
event) and the thickness of the silt layer.
Although hydrodynamic conditions could
cause this layer to be resuspended and
retransported, the areas identified by this
analysis would be likely to experience
sedimentation repeatedly during the
disposal process. Areas predicted to
receive a silt layer thicker than 1 cm after
a single disposal event were considered to
have the potential to expose biota to
contaminants if the site initially had lower
levels of contaminants than the BHNIP
sediments. In sites where the benthic
community was primarily surface dwelling,
this quantity of siltation could smother the
organisms.
The difference in potential biological
exposure to contaminated sediments among
the sites is a function of the footprint and
the length of tune the site is uncapped, as
well as the sediment and benthic quality of
the adjacent areas. Finfish would be less
likely to forage in areas of relatively
degraded sediment and benthic quality if
better resources were typically available
(i.e., if conditions caused by disposal
contrasted markedly with the normal
conditions). Beyond the site (i.e.,
downstream), potential biological exposure
is a function of these factors and the
likelihood that vagrant silt would settle.
C. Site Footprint
The potential disposal sites fall into three
categories of footprint and exposure period
during construction. The shoreline sites
would be completely isolated from Boston
Harbor during construction, resulting hi no
exposure to marine organisms. The in-
channel and Meisburger sites could be
constructed in cells, leaving only a portion
of the total footprint exposed at any one
time. This construction approach would
create frequent disturbance in the cell
footprint throughout its period of use,
discouraging finfish from entering the
area. If finfish were to spend tune
associated with the disposed silts, this
would be more likely to occur at the in-
channel locations because of the similarity
between the BHNDP sediments and the
natural conditions.
Development of the Subaqueous B,
Subaqueous E, Spectacle Island and Boston
Lightship sites in cells would be more
problematic. Therefore, dredged material
could be continuously exposed throughout
the entire dredging project. The quantity
of material to be disposed would require a
large footprint at each of these sites.
Therefore, although finfish would avoid
the area where disposal was actively
occurring, they could spend time in areas
that had been filled but not yet capped.
This likelihood would be offset by the fact
that the disposed sediments would be
dissimilar to the naturally-occurring
sediments at Boston Lightship. Finfish
seeking cooler temperatures during
summer months could be attracted to the
deep pit to be constructed at Spectacle
Island. Since surface sediments near
Spectacle Island contain quantities of silt,
the differences between the BHNIP
sediments and natural conditions might not
be immediately distinct. Therefore, there
is some risk of increased exposure to
finfish near Spectacle Island. Finally,
unless a the disposal site was decked over
immediately, the shoreline/fast-land
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alternatives would resemble ponds along
the waterfront. This could attract birds.
D. Downstream Impacts
With the exception of the shoreline sites,
where virtually no silt would be lost to the
water column during disposal, the aquatic
sites would not differ in the total quantity
of dredged material lost to the system
(about 3-5% of the total released from the
barges). The differences among the sites
would lie in the dispersal of the vagrant
silt. The volume of water (roughly
represented by the depth of the site)
available to dilute the sediments, and the
typical current regime, determine the
concentration of suspended materials, and
the distance from the site this material is
dispersed, before it reaches the substrate.
Thus, deeper sites and sites with regularly
fast currents would exhibit lower
concentrations of suspended materials.
These currents would cause sediments to
be dispersed farther. Concentrations of
sediments on the substrate where they
would be deposited at these sites would be
lower than at sites from which dispersion
was reduced.
The in-channel, Subaqueous B and
Subaqueous E sites would each be exposed
to regular periods of elevated currents. In-
channel sites would be exposed to ship
traffic while Subaqueous sites would be
exposed to tidal currents. These currents
would tend to prevent permanent
deposition of vagrant silts. Because of the
layout of cells in the three channel areas,
most material that dispersed from the
actual disposal activities would settle on an
area that had recently been dredged or was
soon to be dredged. Therefore, there
would be little increased downstream
impact and little increase in biological
exposure potential. Similarly, the
dimensions of Subaqueous B and E would
allow vagrant silt from a large portion of
the disposal events to settle within the site
boundaries.
The Meisburger, Spectacle Island and
Boston Lightship sites would each have a
higher potential for downstream biological
exposure because typical currents would be
more likely to allow sedimentation to
occur, although most vagrant silts would
settle within the disposal site footprint. As
with the in-channel and subaqueous sites,
the extent of downstream sedimentation
would be limited by the dimensions of
each site. The siltation is unlikely to be
thick enough to smother existing benthic
organisms. Finfish would not be deterred
from foraging in these areas.
E. Summary
The likelihood of biological exposure to
contaminated, dredged materials hi the
water column would not differ much
among the disposal sites, as indicated by
the results of the water quality modeling.
There would, however, be differences
among the sites in terms of the potential
for biological exposure to the substrate,
resulting in the following ranking (from
least to greatest potential):
• In-Channel, Shoreline-Partial Fill
• Meisburger 2, Meisburger 7,
Shoreline/fast-land
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• Spectacle Island CAD
• Subaqueous B, Subaqueous E
• Boston Lightship
Biological exposure potential would be
lowest under the in-channel and partial-fill
shoreline scenarios because the character
of the disposed sediments would be similar
to existing conditions at and adjacent to
these sites.
4.2.3 Identification ofThe Least
Environmentally Damaging Aquatic
Alternatives
Table 4-6 provides a summary of the
relative severity of the impacts discussed
in the preceding section at the potential
disposal sites. The in-channel disposal
alternative was consistently ranked among
those alternatives having the least impact.
The partial-fill shoreline alternative was
ranked among the alternatives having the
least impact in most instances. Therefore,
in-channel disposal or partial filling of
shoreline areas would constitute the least
environmentally damaging alternatives for
aquatic disposal of dredged material
unsuitable for disposal at the MBDS.
The In-channel disposal option would offer
a distinct advantage over other sites
because it would confine the disposal of
sediments to areas that would be disturbed
by the dredging for the BHNIP. Other
advantages include the minimal
downstream impacts and potential for
biological exposure. These are both due to
the similarity of the sediments proposed
for disposal to existing conditions within
this portion of the Harbor. The two most
critical drawbacks to the use of these areas
would be the size of the mixing zone and
the effects of vessel traffic on site stability.
Proper management of the disposal
activities would be necessary to minimize
these factors.
Because of the proposal to have dredging
and disposal, at times taking place
simultaneously in two in-channel locations,
the mixing zone would be the sum of that
hi each in-channel location. While this
sum would cause the total area needed for
mixing to be larger than that needed hi the
Outer Harbor, it would represent a
relatively small portion of each section of .
the Harbor. Operational controls, such as
confining disposal to periods around high
tide, would be instituted to minimize the
size and character of the mixing zone.
This would ensure that the mixing zone
did not move upstream or spread across
the entire width of the Harbor.
The effects of vessel traffic on site stability
in in-channel locations can be controlled
by construction and site closure methods.
Areas most vulnerable to disturbance by
vessel traffic have been identified.
Construction of cells in those areas would
need to be scheduled to avoid the once to
twice monthly passages of LNG tankers
because these vessels require the entire
channel width for passage. Other vessels
can maneuver under more restricted condi-
tions, enabling the use of silt curtains
around the disposal site to help confine the
descent of disposal material. Capping of
these areas could include a layer of rock to
armor the sand cap, preventing future
erosion of the cap.
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Partial filling of the shoreline sites,
particularly those located in the Mystic and
Chelsea Rivers, would also have relatively
few environmental impacts. Drawbacks to
use of these sites include the fact that they
are located outside the proposed BHNIP
dredging footprint, and therefore extend
the total project impact area, and site
stability at the edge of each site nearest to
the Harbor. With the exception of the
Reserved Channel site, each of the
shoreline sites is located adjacent to either
an active channel or an active marine
terminal and would, therefore, be
subjected to bottom currents associated
with vessel maneuvering. Filling these
sites would elevate the substrate so that it
could be subjected to even higher
velocities than occur at the bottom of the
channels once the bulkhead was cut back
to the top of the fill (MLW). While the
portion of each site nearest to the Harbor
could be armored with rock, the risk of
site failure would be higher than at in-
channel sites.
The other sites examined would have
greater impacts associated with dredged
material disposal, in particular the
introduction of a large mass of contam-
inated sediments to relatively undisturbed
(Meisburger sites) or recovering (Outer
Harbor sites, Boston Lightship) areas.
Each of these sites faces more substantial
risks to site stability than the Inner Harbor
because sites of the potential severity of
weather-generated bottom currents and the
greater difficulty securing the sites against
these occurrences. Even without such an
event, recovery of the aquatic resources at
any of these sites would be prolonged.
43 PRACTICABILITY ANALYSIS
This section evaluates the practicability of
using each of the potential disposal sites
shortlisted through the site evaluation
process (see Chapter Three) by examining
the following issues:
• Availability
• Permitability
• Constructability
• Logistics
• Monitoring
• Conflicts
• Capacity
• Cost
• Future Use
These issues are defined and discussed hi
the following subsections. These issues
are often inextricably linked with one
another. However, we have attempted to
distinguish sites using these practicability
criteria. Information on each site is
summarized on Table 4-7.
Practicability is defined by the 404(b)(l)
Guidelines as "available and capable of
being done after taking into consideration
cost, existing technology, and logistics hi
light of overall project purposes." Under
NEPA these factors may be included hi the
discussion for determining an agency(s)'
environmentally preferable alternative.
According to NEPA (40 CFR 1505.2(b)),
"an agency may discuss preferences among
alternatives based on relevant factors
including economic and technical
considerations and agency statutory
missions."
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The follow subsections discuss the short-
listed sites in terms of the practicability
concerns listed above.
4.3.1 Availability
4.3.1.1 Upland Sites
Availability is defined by ownership and
jurisdictional control. It reflects whether a
site is privately owned or within the public
domain. Further, it considers whether use
of each site is regulated primarily by state
or federal regulations, or whether the site
has special regulatory status. Sites
privately or municipally-owned are
considered to have low practicability
because of the need to purchase the site.
Sites within state or municipal jurisdiction
are considered to have moderate
practicability but may have complex
permitting issues. Sites beyond state
jurisdiction are considered to have high
practicability because of somewhat less
complex permitting. Special regulatory
status could modify these ratings in either
direction, although those sites whose
special status reflected important
environmental resources (e.g. ACECs)
were eliminated earlier in the site selection
process.
Of the upland (undeveloped) sites, Woburn
and Squantum Point are owned by
municipalities, Everett is owned by a
public utility, and Wrentham is privately
owned. For the lined landfills availability
is not an issue since all have indicated a
willingness to accept portions of the silt.
4.3.1.2 Aquatic Sites
In Massachusetts, coastal waters out to the
three-mile limit are regulated by the
Commonwealth. Use of these waters is
controlled (through the Wetlands
Protection Act, up to 80 feet below MLW)
by the state and the municipality abutting
them. Boston Lightship (and the
Massachusetts Bay Disposal Site for parent
material disposal) is the only site that falls
strictly under federal jurisdiction. All
other aquatic sites are within state waters,
requiring review at the municipal, state,
and federal level. Several of the shoreline
sites (Amstar, Mystic Piers and Revere
Sugar) and the in-channel sites (Mystic
River, Chelsea River and Inner
Confluence) are within the State's
Designated Port Area, a status that
supports water-dependent use (see Chapter
Seven). The remaining aquatic sites are
within State waters but have no additional
regulatory classification. No distinction is
made between the partial-fill and fast-land
scenarios for the shoreline sites on this
basis. Based on this criterion, the aquatic
sites would be ranked for practicability,
due to availability, as:
• Boston Lightship
• Amstar, Mystic Piers, Revere
Sugar, in-channel (Mystic River,
Chelsea River, and Inner
Confluence)
• Little Mystic Channel, Reserved
Channel, Subaqueous B,
Subaqueous E, Spectacle Island,
Meisburger 2, and
Meisburger 7
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4.3.2 Permitabilitv
4.3.2.1 Upland Sites
This issue evaluates the complexity of the
permitting process. It is partially related
to the potential for repeated use of a
particular site beyond the BHNIP. For
inland and coastal sites, permitability
issues are mainly tied to the need for the
proposed disposal site to undergo review
through the state's Solid Waste Siting
Review and Designation process. The
siting and permitting of a new solid waste
facility in the Commonwealth of
Massachusetts is a lengthy process.
Initially an application for the suitability of
the site must be submitted to the
Massachusetts Department of
Environmental Protection. The application
must include: 1) documentation that the
selected site meets the suitability criteria;
2) the engineering design report; 3) the
landfill operations and management plans;
and, 4) certification that the applicant has
complied with the Massachusetts
Environmental Policy Act. The
application is then reviewed by the DEP
and public hearings are held to obtain
comments from the affected community.
The entire process, including site
investigation, landfill design and
permitting, may require three to five
years. The actual time required for the
permitting of a facility may vary from this
estimate, depending on the complexity of
the site conditions and environmental
constraints, time required by the DEP to
review the documentation and the level of
public concern. Thus the siting process
for Solid Waste Facility designation for
mis project could be a serious limitation
for the BHNIP given the proposed 1997
starting date.
Given the difficulty of siting and
permitting a disposal site, the land-based
options may be more suitable for future
maintenance material. The upland sites
therefore are considered to be low in
practicability for the permitability
criterion. Permitability is a relatively
minor issue for the three lined landfills
sites because the landfills are already
permitted to receive special waste. All
would need to have the silt characteristics
reviewed by the State and municipalities
prior to acceptance. Then: rankings for
upland sites for ther permittability criteria
are:
Lined Landfills
Remaining Upland Sites
4.3.2.2 Aquatic Sites
For aquatic sites, their use may require
further study that would extend the period
needed for permitting. This factor would
cause a site to have low practicability for
the BHNIP (although it could still be
practicable for future projects). Another
issue would be whether use of a particular
site would result in the loss of aquatic
habitat. Since this loss would potentially
be mitigable, such sites would be
considered to have moderate practicability
for the BHNIP and future projects. Sites
likely to be suitable only for a one-tune
use, and not resulting in the permanent
loss of aquatic habitat (whether or not
mitigable), are rated as having higher
practicability for the BHNIP.
Three sites, Meisburger 2, Meisburger 7
and Boston Lightship, have capacity well
above that needed for the BHNIP and
would be likely candidates for repeated use
for disposal once approval for this use was
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given. Therefore, regulatory commenters
on the DEIR/S have indicated that it would
be necessary to conduct formal site
designation investigations prior to granting
permits. The formal site designation
process for open water disposal sites is a
minimum of two years long. Given the
importance of these sites (the Meisberger
sites, in particular) as commercial fishing
habitat, this process could take
significantly longer. These factors would
place delays on the BHND? that would
jeopardize the necessary federal funding
for the project.
The fast-land scenario for the five
shoreline sites (Amstar, Cabot Paint, Little
Mystic Channel, Mystic Piers and Revere
Sugar) would result in the permanent loss
of aquatic habitat, thus being a direct
conflict with 404(b)(l) criteria and made
more problemmatic by the lack of
available compensatory resource areas for
mitigation in the Harbor area. Permitting
the remaining aquatic disposal scenarios is
highly practicable.
Review of permitting issues results in the
following ranking of aquatic sites (from
high to low practicability):
• In-channel (Mystic River, Chelsea
River, Inner Confluence)
• Partial-fill shoreline (Amstar,
Cabot Paint, Little
Mystic Channel, Mystic Piers,
Reserved Channel, Revere
Sugar), Subaqueous B, Subaqueous
E, Spectacle Island CAD
• Fast-land shoreline (Amstar, Cabot
Paint, Little Mystic
Channel, Mystic Piers, Revere
Sugar)
• Meisburger 2, Meisburger 7,
Boston Lightship
4.3.3 Constructabilitv/Complexitv of
Engineering
4.3.3.1 Upland Sites
The degree of complexity required to site,
design, build and operate the dewatering
facility is high for all of the upland sites.
The primary engineering and operating
constraint would be the dewatering system,
which would need to be constructed on the
Boston waterfront and used to treat the silt
prior to hauling to any of the upland sites
(See Section 4.1.1.1).
The sheer volume of material (200,000 cy
proposed for upland disposal) is extreme
for most dewatering technologies, with the
exception of air drying, which has a large
acreage requirement and is seasonally
limited. The proposed belt filter presses,
which could be used in combination with
air drying, is standard technology, but is
slow and maintenance intensive.
Additionally, a disposal facility constructed
at any upland site would essentially equal a
lined landfill with a liner; berms;
underdrains; leachate collection system;
pre-,mid-, and post-monitoring; capping;
and a long-term site closure plan. Site-
specific analyses to evaluate risks to the
environment would be required, such as
assessment of the stability and current
contamination levels of the closed,
partially capped landfill underlying
Woburn, and the limits and hydrologic
connections of the Zone II aquifer at
Wrentham. For this practicability
analysis, it is assumed that all four upland
sites have a high degree of complexity,
and therefore a low practicability for the
Project.
The lined landfills are also rated low in
practicability with respect to engineering
complexity because of the need to dewater
the silts at the Harbor prior to transporting
4-32
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to the landfill. However, all other
construction and operation concerns are
eliminated since the disposal facilities
already exist.
4.3.3.2 Aquatic
Constructability or complexity of
engineering concerned with the techniques
needed to prepare and close sites, are
generally rather simple for the aquatic
sites. Site preparation could include
dredging (in-channel and borrow pit sites);
dike construction (subaqueous sites);
bulkhead construction (shoreline partial-fill
or fast-land scenarios with weir structures
to allow drainage); or no site preparation
needed at all (Boston Lightship).
All alternatives, except the fastland
scenarios, would require capping in a
submerged environment. While placing
cap material in shallow conditions (e.g.,
in-channel, shoreline, subaqueous, and
Spectacle Island sites) is a proven practice,
commenters on the DEIR/S raised
concerns about whether this could be
successfully demonstrated at deeper sites
(Meisburger 2, Meisburger 7, and Boston
Lightship).
Compared to upland sites, practicability of
site preparation and closure of aquatic sites
would be high for shallow sites (i.e. In-
channel, Spectacle Island, Subaqueous B
and E) and lower for deep sites such as
Boston Lightship, Meisburger 2 and 7).
4.3.4 Logistics
4.3.4.1 Upland Sites
Logistical concerns include the number of
handlings of the material to be disposed,
hauling distances, and rate of disposal as
controlled by the slowest factor (e.g.,
trucking, dewatering, dredging, avoidance
of sensitive receptors, etc.). For the
upland sites, the material will be handled
several times:
• off-loading for dewatering,
• working during the dewatering
process,
• loading onto trucks for hauling,
• spreading at the disposal facility
Each handling step involves planning;
incurs an increased cost in time and
equipment; and represents a potential risk
to the environment through accidents.
Hauling distance also affects the
practicability of the upland sites. Two
coastal sites are in close proximity to the
BHNIP via barge. Everett is on the
Mystic River, and Squantum Point is hi
Boston Outer Harbor at the mouth of the
Neponset River. In contrast, use of the
two inland sites, Woburn and Wrentham,
would require truck round-trips of 1 and 2
hours, respectively. Depending on the size
of the truck fleet used, the dredging or
dewatering rate could be limited by the
hauling rate. The size and speed of the
truck fleet will be dependent on issues
such as restricted operating hours (due to
noise or air quality effects) in areas of
sensitive receptors, existing traffic
volumes, either in Boston or at the
receiving town, and cost of operation.
Lined landfills have similar logistical
issues as the upland inland sites, having
both multiple handling needs and trucking
requirements. Round-trip trucking times
to the Plainville, Fitchburg/Westiminster,
and E. Bridgewater landfills are estimated
as 2, 3, and 1 hours, respectively.
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The upland sites and lined landfills are
rated relatively low in logistical
practicability due to the multiple handling
required as a result of dewatering and
hauling. Woburn and Wrentham are
especially problematic because their
distances from the Harbor could ultimately
slow the BHNBP dredging rate.
4.3.4.2 Aquatic Sites
The logistics of disposal operations at
aquatic sites are simpler than with land-
based sites because mere is no need for
dewatering prior to transport to the
disposal site. Among the aquatic sites,
handling is most complex for the shoreline
sites because site configuration requires
that silt be offloaded from barges by crane
ramer than dumped from the bottom of the
scow. The sites that could be developed in
cells (in-channel and Meisburger sites) or
require no preparation (Boston Lightship)
would experience the shortest delays
before being available for disposal.
The proximity of the in-channel disposal
sites to the dredging operation make this
alternative the most highly practicable of
those examined. On the other hand, the
distance of the Boston Lightship and
Meisburger sites from the dredging, while
not enough to constrain the production
rate, complicate their use logistically by
necessitating the use of larger barges,
traversing longer stretches of commercially
used waterways, as well as the potential
for more weather-related delays (and
risks). Site preparation at sites such as
Spectacle Island and Subaqueous B and E
would be more extensive, potentially
resulting in the need to stockpile silts
temporarily. As these sites are located in
the Outer Harbor, barges would need to
traverse virtually the entire length of the
Harbor's waterways.
Therefore, Boston Lightship, Meisburger 2
and 7, Subaqueous B and E and Spectacle
Island are considered to be moderately
practicable with respect to logistics. In-
channel and shoreline sites are rated highly
practicable.
4.3.5 Monitoring
4.3.5.1 Upland
Monitoring of the silt disposal process (for
both upland and aquatic sites) will be
required both during and after disposal to
ensure that the silts are adequately
contained and are posing no undue risk to
the environment. For disposal at the
upland sites, monitoring would likely be
required at the dewatering facility as well
as the disposal facility. For dewatering,
monitoring would include Harbor and air
quality monitoring and would cease at the
end of the dewatering phase. At the
disposal facility, monitoring would likely
include groundwater and surface water
sampling for leachate leakage, air quality,
cap and berm stability and leachate
characteristics. These monitoring needs
are standard in the landfill industry and
therefore represent no technological
hurdles but are costly. Monitoring at
Everett and Woburn may be somewhat
complicated by potential contamination
from an adjacent 21-E site at Everett and
the closed on-site landfill at Woburn.
The lined landfills have monitoring
programs currently in place for accepted
wastes. Project monitoring needs for
these sites would be limited to Harbor and
air quality monitoring at the dewatering
facility. This monitoring would cease at
the end of the dewatering phase of the
Project.
The practicability of monitoring at the
upland sites is moderate due to the
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standard, but extensive nature of the
monitoring that is likely to be required.
At the landfill sites, the monitoring
practicability is high because of the limited
monitoring needs at the dewatering site.
4.5.5.2. Aquatic Sites
For disposal at aquatic sites, monitoring
would likely be required to verify
compliance with the projected mixing zone
during disposal operations. Post
construction monitoring would likely be
required to confirm the integrity of the cap
or bulkhead and to verify the recovery of
biological resources.
The practicability of monitoring at the
aquatic sites is moderate at the offshore
and Outer Harbor sites because events that
could affect the integrity of the cap would
be infrequent, although potentially severe
hi nature. In addition, monitoring would
be affected by the more complex structure
of the existing biological resources at these
sites indicating that the period of recovery
would be prolonged. In contrast, the
practicability of monitoring sites in the
Inner Harbor would be high because the
frequency of occurrence of factors that
could influence site stability would be high
(allowing rapid confirmation of cap
integrity), and because existing biological
resources are adapted to this stressed
environment and would be expected to
recover rapidly. Therefore aquatic sites
are ranked with respect to monitoring as:
• High practicability - In-channel,
shoreline (partial-fill and fastland)
• Moderate practicability - Boston
Lightship, Meisburger 2,
Meisburger 7, Spectacle Island,
Subaqueous B and Subaqueous £
4.3.6 Conflicts with Other Activities
4.3.6.1 Upland
The upland sites are all located on inactive
lands. No known projects are proposed at
Everett or Woburn. There has been
mention of a potential industrial park usage
at the Wrentham site. The Town of
Woburn has expressed possible interest for
assistance by the BHNIP hi permanently
closing the partially capped landfill
currently on the Woburn site. At
Squantum Point, the Metropolitan District
Commission has plans for a park on a
portion of the proposed disposal site. The
construction of the disposal facility would
require coordination with the MDC to
ensure the needs of both projects can be
met. It is likely that a park can be
accommodated on the site once the
disposal facility was closed and capped.
Use of the lined landfills does not interfere
with any known project.
There is a high practicability for all lined
landfills, Everett, Woburn, and Wrentham;
and moderate practicability for Squantum
Point because of the proposed MDC park.
4.3.6.2 Aquatic Sites
There are three basic areas of potential
conflict between aquatic disposal activities
and other site uses: public works projects,
fishing activities and navigation. Of these,
there is the potential for long-term
interference with public works projects at
some sites that would require mitigative
action. Two sites (Little Mystic Channel
and Reserved Channel) have CSOs on site.
Either the partial-fill or fastland scenario at
the Little Mystic Channel site or the
partial-fill scenario at Reserved Channel
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would require rerouting of these CSOs.
There is concern that the Spectacle Island
site could disturb the integrity of the
closure of the Spectacle Island landfill and
subsequent park development. Additional
site investigations would be necessary to
evaluate the likelihood that disposal
activities would avoid conflict activities on
Spectacle Island.
Water quality modelling (Appendix F; and
Section 4.2) indicates that disposal would
not affect the proposed artificial reef. The
Meisburger sites are proximal to the
MWRA sewage outfall currently under
construction. There is concern, on
MWRA's part, that the proximity of these
activities could make interpretation of
outfall monitoring results extremely
difficult given the coincidence of dredging
disposal with the early stages of the new
outfall operation. The Meisburger.sites
would be considered to have low
practicability for this criteria.
Interference with fishing activities would
cease at the completion of the disposal
operations, although recovery of the
resource would extend for a longer period.
Each of the offshore sites, Meisburger 2,
Meisburger 7 and Boston Lightship, were
found to support large standing stocks of
fishable resources. Meisburger 2 and 7
are both heavily fished for lobster.
Lobstering activity is variable in Boston
Harbor, but is more focussed in the Outer
Harbor. The Chelsea River provides
habitat for juvenile whiter flounder.
Because of the current status of the
fisheries resources and the fishing industry
in New England, sites that would
experience this type of conflict are also
considered to have low practicability for
the BHNJP unless mitigative actions are
readily available.
Disposal activities at sites that are located
within designated navigation channels
(Mystic River, Chelsea River, Inner
Confluence and Subaqueous B) could
interfere with navigation during the period
while disposal occurred. Interference
would cease when the disposal was
completed. The degree of interference
could be minimized by careful
management of disposal activities and
administration of navigational restrictions.
Navigational conflicts were considered to
rank these sites as having moderate
practicability.
The remaining sites, Amstar, Cabot Paint,
Mystic Piers, Revere Sugar and
Subaqueous E would conflict with other
uses. Therefore, they are rated as having
high practicability for dredged material
disposal.
In terms of conflicts with other activities,
the potential aquatic disposal sites would
be ranked from high to low practicability:
• Amstar, Cabot Paint, Mystic Piers,
Revere Sugar, Subaqueous E
• In-channel (Mystic River, Inner
Confluence), Subaqueous B
• Little Mystic Channel, Reserved
Channel, In-channel (Chelsea
River)-, Spectacle Island,
Meisburger 2, Meisburger 7,
Boston Lightship
4.3.7 Capacity
Site capacity is an easy factor to quantify.
However, direct comparison across sites,
especially between upland and aquatic is
not simple because many of the sites
examined for the BHND? could provide
only a portion of the needed capacity. In
the most simple terms, those sites that
could provide the capacity needed for the
entire volume of silt that would be dredged
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during the BHNIP would have the highest
practicability. Those sites that could
provide at least 30% (about 400,000 cy) of
the needed capacity would have moderate
practicability for the BHNIP. Those sites
that could provide less than 30% of the
needed capacity for the BHNIP would have
low practicability. The short-listed sites fit
these categories as follows:
* High - In-channel sites combined,
Spectacle Island,
Meisburger 2, Meisburger 7,
Boston Lightship
• Moderate - Wrentham, Little
Mystic Channel (fastland),
Subaqueous B, Subaqueous E
• Low - Woburn, Squantum Point,
Everett, lined landfills, fast-land
shoreline sites (Amstar, Cabot
Paint, Mystic Piers, Revere
Sugar), partial-fill shoreline sites
(Amstar,Cabot Paint, Little Mystic
Channel, Mystic Piers, Reserved
Channel, Revere Sugar)
The DEIR/S identified possible
combinations of sites that could provide
the required capacity for the BHNIP.
These combinations are described in
Section 3. Commenters on the DEIR/S
favored combination options to achieve the
capacity needs including Al (all landfills);
Bl (all aquatic shoreline sites); B5 (various
combinations of aquatic sites); and C1-C4
(combinations of upland and aquatic sites).
It was determined in the DEIR/S that the
landfills (Option Al) were incapable of
accepting the total quantity of silt for
disposal. Further investigations for the
FEIR/S found that the silt from the BHNIP
would require dewatering and may be
unsuitable for daily cover and contouring
it at these landfills. Therefore, the landfill
capacity continues to be inadequate for the
BHNIP. Additionally, several of the
comments received on the DEIR/S
indicated a reluctance to see permitted
landfills in the state used for large scale
dredge material disposal. Smaller scale
projects may be more suited to landfill
disposal.
In the Bl combinations, it would take a
minimum of four shoreline sites to
accommodate the entire volume of silt
generated by the BHNIP. A possible
combination would include filling Little
Mystic Channel, Amstar, and Revere
Sugar to fastland (totalling 1,285,000 cy)
and partially filling (35,000 cy) Mystic
Piers. This would result in the loss of
habitat at these locations without the
benefit of readily available compensatory
mitigation.
Option B5 could be developed in many
ways. Use of two of the federal channels
for disposal could be supplemented with a
shoreline site (most likely Little Mystic
Channel). Costs for this scenario could be
minimized by distributing the disposal in
the most cost-effective way. However,
this would still be a more expensive
alternative than some of the others.
Combining two in-channel locations with
either a subaqueous site or a borrow pit
site would be less expensive than including
a shoreline site because of the reduced
infrastructure. Subaqueous E could be
combined with the fastland scenario at
Little Mystic Channel to attain the
necessary volume. In this case, there
would be some excess capacity. It might
be appropriate to leave this at Little Mystic
Channel for use in future use. The two
subaqueous sites could be combined with a
smaller shoreline site such as Mystic Piers
(fastland) or Reserved Channel (partial
4-37
-------
fill). Either of these options would use
virtually the full capacity of the three sites.
A final combination could include the two
subaqueous sites and a portion of one of
the borrow pits. In this option, reserving
excess capacity at the borrow pit sites
could enable their use in the future.
The DEIR/S "C" options include
combinations of land-based and aquatic
sites. Because of constraints associated
with dewatering, it has been assumed that
only 200,000 cy could be designated for
upland disposal from the BHNIP. Either
Squantum Point or Wrentham could
provide 200,000 cy or greater capacity.
The small capacity of Everett (37,000 cy)
precludes practicable use of this site in the
BHNIP. Its prime location may make it
suitable for future, smaller projects,
however, use of Squantum Point or
Woburn in conjunction with a single,
moderately sized aquatic site for the
remainder of the silts would accommodate
the BHNIP. Use of Wrentham for part of
the BHNIP silts would leave a portion of
that site (approximately 250,000 cy)
available for future dredging projects.
Also, capacity alone is not a deciding
factor in practicability analysis. As
described in previous subsections, these
are logistical, engineering, and
permittability issues which complicate the
capacity discussion.
The capacity of the various sites for
projects other than the BHNIP cannot be
fully projected here. Generally, it would
be expected that a project proponent would
attempt to identify a single site that would
have sufficient capacity for the dredged
material that could not be disposed in a
designated disposal area.
4.3.8 Cost
A general comparison of the cost of using
individual disposal sites can be made on a
unit price (cost per cubic yard) basis. The
costs listed on Tables in Chapter Three
reflect use of the full capacity of each site
except the Meisburger 2 and 7 and the
Boston Lightship sites where costs are not
linked directly to volume. Based strictly
on unit cost, the sites would be ranked
from highest to lowest practicability as
follows:
• High - Boston Lightship ($16);
Subaqueous B, Subaqueous E,
Spectacle Island ($20);
• Moderate - In-channel (Mystic
River, Chelsea River, Inner
Confluence) ($30), Meisburger 2,
Meisburger 7, Little Mystic
Channel (fastland), Mystic Piers
(fastland) ($30-39); Little Mystic
Channel (partial-fill), Mystic Piers
(partial fill), Amstar (fast-land),
Squantum Point ($40-51);
• Low - Amstar (partial fill),
Reserved Channel (partial fill),
Revere Sugar (fast-land), Cabot
Paint (fastland), East Bridgewater,
Wrentham, Woburn, Everett ($60-
80); Revere Sugar (partial fill),
Plainville, FitchburgAVestminster
(>$90); Cabot Paint (partial fill)
($360)
4.3.9 Future Use
This issue is linked to capacity and
permitability because it addresses the
questions of whether a particular site could
experience repeated use and whether the
site would be available if it is not used for
the BHNIP. Ranking the disposal sites for
future use has no direct meaning for this
4-38
-------
current project. This is provided in
accodance with the MEPA directive to
consider future needs and provide a
consideration of options.
4.3.9.1 Upland Sites
All of the upland sites may be more
feasible for future use than for the BHNIP,
due primarily to the potentially lengthy
permitting process required for siting an
upland lined disposal facility. The
proximity of Everett and Squantum Point
to Boston Harbor make these sites
especially attractive for dredge disposal.
Even other ports may find these more
accessible than overland transport. The
small size of Everett may preclude its
feasibility for anything but a local small
project. However costs and other design
factors may eliminate upland monofills as
reasonable options for smaller dredge
projects. Again, dewatering, hauling and
other related issues remain.
An advantage offered by upland sites over
aquatic sites is the ease of construction of
cells for repeated use by several dredge
projects. The large size of Wrentham
makes it especially attractive as a multiple
use site, however costs of dewatering and
construction may keep upland sites as
impracticable.
4.3.9.2 Aquatic Sites
The in-channel sites are unique in that they
would be available only when the channels
are dredged, either for improvement or
maintenance dredging. These sites would
not be available for future dredging
projects mat are not directly linked to
channel dredging. Several options were
discussed hi Section 4.3.7 that consider
using a portion of the available in-channel
capacity. If once of these options was
identified as the least environmentally
damaging practicable alternative (LEDPA),
the remaining tributary could be available
for future channel maintenance operations.
For the partial-fill shoreline alternatives,
two factors combine to make multiple use
of these sites impracticable. The
construction costs are relatively high and
would have to be incurred by the first
user. In addition, interim closure of these
sites (capping and cutting off of the
bulkhead to restore tidal flow) would make
reuse of the site logistically difficult.
One BHNIP combination option, involving
Little Mystic Channel and Subaqueous E,
could yield an excess capacity of about
111,000 cy. Underfilling Little Mystic
Channel initially could allow limited future
use, probably on a one-time basis.
Without considering complex combinations
of numerous sites, no other shoreline site
would have the potential for repeated use.
The Subaqueous sites (B and E) would be
suitable for a one-time use only. The
dimensions of the perimeter dike and the
cap needed to contain silt at these sites
represent a significant portion of the total
site footprint. Development in cells would
result in further reductions in site capacity.
This would preclude multiple uses of these
sites.
While the geological conditions at the
Spectacle Island CAD site suggest that it
could not be developed in cells for the
total BHNIP volume, it would likely be
possible to construct cells of smaller
volume without compromising the site's
structural integrity. Thus two options that
were described in Section 4.3.7 in which
the Spectacle Island (as a representative
4-39
-------
borrow pit) site was combined either with
the two Subaqueous sites or a combination
of in-channel sites, could result'in excess
capacity at Spectacle Island that would be
usable in the future.
The Meisburger sites each have the
potential to provide capacity far in excess
of the BHNIP needs. Because these sites
would be developed as relatively shallow
borrow pits over large footprints, there is
limited concern for structural integrity
between cells. If either of these sites was
used for the BHNBP, it is highly likely that
there would be interest hi using them again
in the future. The large capacity available
would generate interest in repeated use.
As stated in Section 4.3.2, however, use
of either site would probably require a
formal site designation study.
There are no known physical limitations to
the capacity of the Boston Lightship site.
As with the Meisburger sites, use for the
BHNIP would not preclude future use and
would likely encourage it, triggering the
need for a formal site designation study.
Again, even if this site is not used for the
BHNIP, there may be further interest in
using it for other projects. It would be a
candidate for repeated uses.
4.5 IDENTIFICATION OF THE
PREFERRED ALTERNATIVE FOR
THE BOSTON HARBOR
NAVIGATION IMPROVEMENT AND
BERTH DREDGING PROJECT
(BHNIP)
Selection of the preferred alternative must
consider both environmental impacts (as
addressed in Sections 4.2 and 4.3) and
practicability (as addressed in Section 4.4)
of the alternatives under review. Both
NEPA and MEPA emphasize the concept
of selecting the least environmentally
damaging alternative (LEDA) that is
practicable for the project proponent to
construct. Thus, the sites that were
identified as having the lowest levels of
environmental impacts for the BHNIP
disposal were examined for practicability.
The sites that would incur the lowest level
of environmental impacts were identified
in Sections 4.2 and 4.3. The LEDA sites
are:
A. Land-based:
lined landfills
Everett
S quantum Point
Woburn
Wrentham
B. Aquatic:
Amstar (partial fill)
• Cabot Paint (partial fill)
• Little Mystic Channel
(partial fill)
• Mystic Piers (partial fill)
• Reserved Channel (partial
fill)
• Revere Sugar (partial fill)
• Mystic River in-channel
• Chelsea River in-channel
• Inner Confluence in-
channel
These sites were reviewed in terms of cost
and capacity (Table 4-7), as a first step hi
assessing their practicability. This review
concluded that most of the LEDA sites
were less desirable for the BHNE? because
of high cost or low capacity.. The
surviving sites are Squantum Point, Little
Mystic Channel (partial fill), Mystic River
(in-channel), Chelsea River (in-channel)
and Inner Confluence (in-channel).
In order to distinguish among these sites,
the environmental impacts and
practicability issues were reexamined.
Squantum Point was eliminated at this
stage because of intertidal dredging and
4-40
-------
wildlife habitat impacts (Table 4-2) and its
low practicability for availability,
permitting, ease of engineering and
logistics (Table 4-7). Of the remaining
four sites, use of Little Mystic Channel
would result in filling outside the footprint
of the dredging project and a permanent
alteration in depth from subtidal to
intertidal, both of which were viewed as
more substantial environmental impacts.
In addition, Little Mystic Channel was
lower in practicability for most issues
(availability, permittability, ease of
engineering, and logistics; Table 4-7) than
the in-channel sites.
The preferred alternative for the disposal
of silts from the BHNIP is, therefore, in-
channel disposal in the Mystic River,
Chelsea River and Inner Confluence,
within the footprint of the dredging
project. Distinct advantages of using this
alternative include confining disposal
impacts to the areas impacted by dredging
activities, anticipated rapid recovery of
biological resources to preexisting status,
ability to sequester dredged silts near their
point of origin, and ability to
compartmentalize the disposal operation.
4.6 FUTURE MAINTENANCE
The selection of the disposal site for future
maintenance dredging must reexamine the
environmental and practicability criteria
discussed above. Factors such as sediment
characteristics and volume of the dredging
project will be critical in determining the
suitability of the disposal sites. Sites such
as Little Mystic Channel and Squantum
Point would receive high priority in this
review. Sites that were identified in this
review as having lengthy permitting needs,
but were otherwise reasonable, would also
be reviewed carefully. The disposal site
for future maintenance will be determined
based on the appropriate environmental
regulations and technical evaluations at that
time. The New England Division Corps
recommends, and will participate with the
Commonwealth in, conducting an overall
regional dredged material management
plan for future maintenance of all of
Massachusetts Bay's harbors.
4-41
-------
-------
Boston Harbor Dredging Project EIR/S
Rgure4-l. Locations of short-listed sites.
Scale: 0 10
Apprax. Scale in Miles
Source:
USGS Quadrangles
Revised by NAI to reflect pertinent site conditions.
-------
TABLE 4-1. SUMMARY OF IMPACTS TO BHNIP LAND-BASED ALTERNATIVE DISPOSAL SITES.
Site
All Lined
Landfills
Everett
Wrentham
Woburn
Squantum
Point
Capacity (cy)
200,000
37,000
315,000
158,600
210,000
Permanent Losses
None
Highly disturbed
vegetation and
wildlife habitat.
Large tract of forest
and shrubland.
1 acre of forested
wetland. Highly
disturbed vegetation
and wildlife habitat.
Moderately disturbed
vegetation and
wildlife habitat.
Temporary Losses
None
Channel dredging in
subtidal; shorebird
use; common tern
use.
Odor and noise
along trucking route.
Odor and noise
along trucking route.
Channel dredging in
subtidal; shorebird
use.
Permanent Alteration
None
Same as losses.
Same as losses.
Same as losses.
Channel dredging in
intertidal wetlands.
Indirect Impacts
Odor and noise
would be part of
landfill operation
Odor and noise.
Forest
fragmentation; tax
loss; odor and noise.
Odor and noise.
Freshwater runoff;
park plans' odor and
noise.
-c.
.1
03
-------
TABLE 4-2. COMPARISON OF THE SIZE AND EFFECT OF DIRECT IMPACTS AT BHNIP ALTERNATIVE AQUATIC
DISPOSAL SITES.
SITE
SHORELINE: FILL TO FASTLAND
Amstar
Cabot Paint
Little Mystic Channel
Mystic Piers
Revere Sugar
SHORELINE: PARTIAL FILL
Amstar
Cabot Paint
Little Mystic Channel
Mystic Piers
Reserved Channel
Revere Sugar
IN-CHANNEL
Mystic River
Chelsea River
Inner Confluence
SUBAQUEOUS DEPRESSIONS
Subaqueous B
Subaqueous E
BORROW PITS
Spectacle Island
Meisburger 2
Meisburger 7
DISPOSAL SITES
Boston Lightship
DIRECT IMPACT
IN EXCESS OF
DREDGED AREA
3.5 acres
5.6 acres
15.0 acres
2.7 acres
3.7 acres
3.5 acres
5.6 acres
15.0 acres
2.7 acres
7.7-16.6 acres
3.7 acres
0 acres*
0 acres*
0 acres*
83 acres
79 acres
45 acres +
86 acres +
121 acres +
100 acres (est.)
EFFECT OF IMPACT
Permanent loss of benthic productivity and
feeding and refuge habitat.
Temporary loss of benthic productivity and
feeding and refuge habitat. Positive effects:
existing contaminated sediments capped; in-
creased productivity in Reserved Channel.
Permanent alteration in depth (subtidal to
intertidal) and substrate.
Temporary loss of benthic productivity con-
current with and in same footprint as
improvement dredging of existing channels.
Temporary loss of benthic productivity and
feeding and refuge habitat. Permanent alter-
ation of depth and substrate character. Per-
manent loss of cooler water refuge habitat.
Temporary loss of benthic productivity within
pit; undefined area for cap storage would ex-
perience temporary loss of benthic productivi-
ty; cap may require armoring leading to per-
manent change in substrate character and ben-
thic community.
Temporary loss of benthic productivity; per-
manent change of depth and substrate charac-
ter.
EXISTING BENTHIC
PRODUCTIVITY
VALUE
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
Low
High
High
High
Moderate-High
Moderate-High
Moderate-High
POTENTIAL
RECOVERY
RATE
No Recovery
No Recovery
No Recovery
No Recovery
No Recovery
Rapid
Rapid
Rapid
Rapid
Rapid
Rapid
'.?..
Rapid
Rapid
Rapid
Moderate
Moderate
Moderate
Slow
Slow
Slow
*The entire disposal footprint (about 56 acres in the Mystic River, 40 acres in the Chelsea River and 21 acres in the Inner Confluence) would be within the boundaries of the
channel improvement dredging.
-------
TABLE 4-3. SUMMARY OF SHORT-TERM WATER QUALITY EFFECTS FROM DISPOSAL AT
BHNIP ALTERNATIVE DISPOSAL SITES.
SITE
SHORELINE: FILL TO FASTLAND
Amstar
Cabot Paint
Little Mystic Channel
Mystic Piers
Revere Sugar
SHORELINE: PARTIAL FILL
Amstar
Cabot Paint
Little Mystic Channel
Mystic Piers
Reserved Channel
Revere Sugar
IN-CHANNEL
Mystic River
Chelsea River
Inner Confluence
SUBAQUEOUS DEPRESSIONS
Subaqueous B
Subaqueous E
BORROW PITS
Spectacle Island
Meisburger 2
Meisburger 7
DISPOSAL SITES
Boston Lightship
MIXING ZONE
Size (acres)"
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
12.4
30.0
14.7
10.4
8.9
7.7
9.6
9.6
10.0
Parameter
of Concern
TSS
TSS
TSS
TSS
TSS
TSS
TSS
TSS
TSS
EXCEEDANCES OF CHRONIC
WATER QUALITY CRITERIA
OR STANDARDS
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
N/A
None anticipated
None anticipated
None anticipated
None anticipated
None anticipated
None anticipated
None anticipated
None anticipated
None anticipated
Oi
"In-channel: smaller mixing zone represents typical project disposal schedule; larger mixing zone caused by anticipated period of higher-than-average disposal rate.
-------
TABLE 4-4. POTENTIAL SOURCES OF SITE DESTABILIZATIONTHAT COULD ARISE DURING
AND/OR AFTER CONSTRUCTION AT BHNIP ALTERNATIVE DISPOSAL SITES.
SITE
SHORELINE: FILL TO FASTLAND
Amstar
Cabot Paint
Little Mystic Channel
Mystic Piers
Revere Sugar
SHORELINE: PARTIAL FILL
Amstar
Cabot Paint
Little Mystic Channel
Mystic Piers
Reserved Channel
Revere Sugar
IN-CHANNEL
Mystic River
Chelsea River
Inner Confluence
SUBAQUEOUS DEPRESSIONS
Subaqueous B
Subaqueous E
BORROW PITS
Spectacle Island
Meisburger 2
Meisburger 7
DISPOSAL SITES
Boston Lightship
TIDAL CURRENTS
During
X
X
X
After
-
X
X
X
STORM & WIND
EVENTS
During
X
X
X
X
X
X
After
X
X
X
X
X
X
VESSEL ACTIVITY
During
X
X
X
X
After
X
X
X
X
X
X
X
X
X
OTHER
During
CSOs
CSOs
After
CSOs
CSOs
"mi?
-C
\
-------
TABLE 4-5. SUMMARY OF POTENTIAL IMPACTS TO DOWNSTREAM BIOLOGICAL AND HUMAN USE RESOURCES
FROM BHNIP DISPOSAL SITE ALTERNATIVES.
4:
SITE
SHORELINE: FILL TO FASTLAND
Amstar
Cabot Paint
Little Mystic Channel
Mystic Piers
Revere Sugar
SHORELINE: PARTIAL FILL
Amstar
Cabot Paint
Little Mystic Channel
Mystic Piers
Reserved Channel
Revere Sugar
IN-CHANNEL
Mystic River
Chelsea River
Inner Confluence
SUBAQUEOUS DEPRESSIONS
Subaqueous B
Subaqueous E
BORROW PITS
Spectacle Island
Meisburger 2
Meisburger 7
DISPOSAL SITES
Boston Lightship _
—f^^± ========a==s=s
- - ^= ,.T,.^m 1
BIOLOGICAL RESOURCES
Anadromous
Fish
P
P
P
P
P
P
P
P
P
P
P
P
P
=====
Winter
Flounder
P
P
P
P
P
P
P
P
P
P
P
D,P
D,P
D,P
D,P
D,P
D,P
D,P
D,P
D,P
======
Lobster
P
P
P
P
P
P
P
P
P
P
P
P
P
D,P
D,P
D,P
D,P
D,P
D,P
=====
Clams
P
P
P
P
P
Benthos
P
P
P
P
D,P
D,P
D,P
D,P
D,P
D,P
D,P
D,P
D,P
HUMAN USE RESOURCES
Fishing
Grounds
D,P
D,P
P
D,P
D,P
D,P
Water
Intake
p
p
P
Human
Contact
P
P
D = during disposal
P = post-construction cap failure
-------
TABLE 4-6. SUMMARY OF RELATIVE SEVERITY OF IMPACTS" OF POTENTIAL BHNIP AQUATIC DISPOSAL
ALTERNATIVES.
DIRECT IMPACTS
• In-channel
• Shoreline-partial
• Spec Is, Meis 2, Meis
7, BLS
• Sub B, Sub E
• Shoreline-fastland
SITE STABILITY
CONSTRUCTION
• Shoreline-partial,
fastland
• In-channel
• Meis 2, Meis 7
•BLS
•SubE
• Sub B, Spec Is
POST-CONSTRUCTION
• In-channel, shoreline-
fastland
• Meis 2, Meis 7
• Shoreline-partial
•SubE
• SubB
• Spec Is, BLS
DOWNSTREAM IMPACTS
CONSTRUCTION
• In-channel, shoreline-
partial, fastland
• Spec Is, Sub B, Sub E,
Meis 2, Meis 7, BLS
POST-CONSTRUCTION
• In-channel, shoreline-
partial, fastland
• Meis 2, Meis 7, BLS
• SubB
• Sub E, Spec Is
BIOLOGICAL
EXPOSURE
• In-channel, shoreline-
partial
• Meis 2, Meis 7,
shoreline-fastland
• Spec Is
• Sub B, Sub E
•BLS
"Listed in order of least to greatest effect within each impact.
-------
TABLE 4-7. SUMMARY OF FACTORS AFFECTING PRACTICABILITY OF ALTERNATIVE DISPOSAL SITES.
"fN».
-v
~r-
^-0
UPLAND SITES
Lined LnudfiUs
East Bridgewater
Plainville
Fitchburg/Westminister
Coastal Sites
Squanumi Point
Everett
Inland Sites
Woburn
Wrentham
Availability
HIGH1
No purchase
required]
ii
w
..
LOW
[Municipally
owned)
[Privately owned]
LOW
[Municipally
owned)
[Privately owned)
Permitting
MODERATE
[Dewatcring]
••
M
"
LOW
[Solid Waste
siting;
dewalering]
n
LOW
[Solid Waste
siting;
dewatering]
"
Ease of Engineering
LOW
[Dewatering facility]
»
..
•
LOW
(Monofill facility;
dewalering facility]
|(
«
LOW [Dewatering;
multiple handling;
haul by truck)
[Former landfill]
LOW
Logistics
LOW
[Dewatering; Multiple
landling; hauling distance)
il hour trucking]
[2 hours trucking]
[3 hours trucking]
LOW
[Haul by barge; dewalering;
double handling]
i,
«
LOW [Dewatering;
multiple handling; haul by
truck]
»
Ease of
Monitoring
HIGH
[Dewatcring
only]
II
"
ii
MODERATE
[Groundwater;
air quality;
dewatering)
•'
[Complicated by
adjacent 21-E]
[Complicated by
existing closed
landfill]
MODERATE
Compatibility
with other
Activities
HIGH
[No conflicts)
n
*
n
MODERATE
[MDC park
plans]
HIGH
[No conflicts]
HIGH (No
Conflicts)
it
H
Capacity [cy]
LOW
[200,000 cy]
[200,000 cy)
[200,000 cy)
MODERATE21
0,000 cy
LOW 37,000
cy
LOW 158,600
cy
MODERATE
451,200
Cost
LOW
$62
$94
$108
MODERATE
$51
LOW
$76
LOW
$69
$62
-------
AQUATIC
Shoreline-Fnstlaud
Amslar
Cabot Paint
Little Mystic Channel
Mystic Piers
Revere Sugar
Shoreline-Partial Fill
Amslar
Cabot Paint
Little Mystic Channel
Availability
MODERATE
Designated Port
Area
Designated Port
Area
LOW
State Waters
MODERATE
Designated Port
Area
ii
••
"
LOW
State waters
Permitting
MODERATE
[Aquatic
habitat loss]
"
H
"
it
HIGH
[No
designation
required]
"
Ease of Engineering
MODERATE
[Bulkhead with
drainage]
11
"
11
11
MODERATE
[Bulkhead, cap,
partial removal of
bulkhead]
"
Logistics
MODERATE
[Double handling likely;
close to dredge site]
"
"
11
11
MODERATE [Double
handling likely; close to
dredge site]
»
Ease of
Monitoring
MODERATE
[Engineered
structure]
"
"
11
H
MODERATE
[Engineered
structure,
resource
recovery rapid]
H
Compatibility
with other
Activities
HIGH
[None]
"
LOW
fCSOs]
HIGH
[None]
"
HIGH
"
LOW
[CSOs]
Capacity [cy]
LOW
241,000
198,000
MODERATE
840,000
LOW
187,000
204,000
LOW
128,000
18,000
373,000
Cost
LOW
$50
$65
MODERATE
$47
$38
LOW
$61
LOW
$62
$362
MODERATE
$47
-------
Mystic Piers
Revere Sugar
Reserved Channel
In-Climuiel
Mystic River
Chelsea River
Inner Confluence
Siibnaiieous Deuressioiis
Subaqueous B
Subaqueous E
Availability
MODERATE
Designated Port
Area
MODERATE
Designated Port
Area
LOW
State Waters
MODERATE
Federal Channel,
DPA
-
»
LOW
LOW
State Waters
LOW
Permitting
HIGH
No designation
required
H
No
designation
required
-
HIGH
»
••
••
LOW
(Designation
required)
"
LOW
Ease of Engineering
MODERATE
»
H
HIGH
Dredge cells, sand
cap
«
"
HIGH
Dike [clay] + cap
HIGH
Logistic
MODERATE
-
•
HIGH
Close to dredging, little
need to stockpile, single
handling
"
"
MODERATE
[Delay until dike material
available, near dredge site
but requires traversing
entire ship channel]
MODERATE
Ease of
Monitoring
MODERATE
It
»
MODERATE
"
"
11
MODERATE
[Cap integrity,
resource
recovery
[intermediate]
MODERATE
Compatibility
with other
Activities
HIGH
[None]
HIGH
[None]
LOW
[CSOs]
MODERATE
LOW
[Navigating fish]
MODERATE
[Navigation]
MODERATE
MODERATE
Capacity [cy]
98,000
86,000
186,000
HIGH
742,100
332,400
245,900
MODERATE
562,000
MODERATE
591,000
Cost
$47
LOW
$93
$45
MODERATE
30
30
30
LOW
,
$20
LOW $19
-------
Borrow Pits
Spectacle Island
Meisburger 2
Meisburger 7
Disposal Sites
Boston Lightship
Availability
LOW
State Waters
State Waters
State Waters
HIGH
Federal Waters
Permitting
LOW
No designation
required
LOW
Disposal Site
Designation
Study
»
LOW
(Site Designation
Needed)
Ease of Engineering
HIGH
Dredge pit, self cap
MODERATE
Dredge cells [but
marginal at this
depth], self cap
••
MODERATE
No site preparation;
capping unconfirmed
Logistics
MODERATE
[Barging through entire
harbor minimal delay for
site prep.]
**
»
MODERATE
Most distant aquatic site but
distance would not constrain
production rate
Ease of
Monitoring
MODERATE
LOW
Cap integrity,
resource
recovery,
(prolonged]
»
LOW
Compatibility
with other
Activities
MODERATE
Cap integrity,
resource
recovery,
[intermediate]
11
H
it
MODERATE
Capacity [cy]
HIGH
1,320,000
1,320,000+
1,320,000+
HIGH
Unlimited
[1,320,000+]
Cost
MODERATE
$21
$30
$33
LOW
$16
-C
'HIGH = highly practicable for Ihe specific criterion
MODERATE = moderately practicable for the specific criterion
LOW = low practicability for Ihe specific criterion
-------
-------
-------
-------
Chapter Five: Dredging Management Plan
The Dredging Management Plan, described
in this section, provides an overview of the
dredging operation proposed for the
improvement of Boston Harbor and related
berth facilities. The key elements of the
Plan include: a description of alternative
dredging equipment and specific
recommendations for this project; dredged
material disposal operations; sequencing of
the dredging and disposal operations; an
overview of potential environmental
impacts caused by dredging and proposed
techniques and equipment to mitigate these
impacts; establishment of dredging
performance standards; a description of
recommended monitoring plans during
dredging and for long term post-
construction monitoring; and a discussion
of operational contingency plans which
would be implemented to assure the safe
and successful completion of the project.
The Plan focuses upon those details of
.dredging and related operations as they
may impact the environment.
5.1 SELECTION OF DREDGING
METHOD
A broad range of dredging equipment
•types and operating techniques are
available for the dredging of sediments and
rock from Boston Harbor. Identification of
the best dredging method for the BHNIP
requires the consideration of the factors
described in the following paragraphs.
5.1.1 Project Objectives
Approximately 2.8 million cubic yards of
in-situ material will be removed as part of
the BHNIP. This total volume includes an
estimated 1.1 million cubic yards of
contaminated silt, 1.6 million cubic yards
of parent material, and 88,000 cubic yards
of rock. As described in Chapter 2.0, an
additional 1.8 million cy of parent material
will be dredged to provide in-channel
disposal volume for the silt.
Dredging and rock removal will take place
in the existing authorized Federal channel
and in berth facilities throughout the
harbor area. The proposed project depth is
-38 ft. (MLW) in the Chelsea River
(known locally as Chelsea Creek) and -40
ft. (MLW) in sections of the Mystic River,
Reserved Channel, and a portion of the
Main Ship Channel. The maximum depth
of dredging will typically be approximately
-55 ft (MLW) with some areas reaching -
70 ft. (MLW) to prepare the in-channel
disposal facilities.
Boston Harbor is subject to a normal tidal
range of approximately 9.5-ft. Peak tidal
currents range from approximately 0.7-
knots through the Inner Confluence to
around 0.5-knots hi both the Mystic River
channel and the Chelsea Creek. The
project site is subject to periodic northeast
storms and seasonal hurricanes which can
generate severe winds, waves, and extreme
water surface elevations. Historic storm-
related high water events, measured at the
Commonwealth Pier, have exceeded 14 ft.
5-1
-------
(MLW). Such storm events will challenge
the operating limits of personnel and
equipment.
Dredging operations will be performed
such that all of the identified contaminated
silts ace efficiently removed. The
equipment used must remove the maximum
amount of sediments with minimum cross-
contamination of silt and parent material.
This will require the use of equipment
which can consistently dredge to a depth
tolerance of less than 0.5 feet.
Project objectives also require that the
selected dredge equipment be capable of
accomplishing the task within time allotted
while assuring a safe and environmentally
responsible project. Dredge and material
transport downtime must be minimized to
avoid costly additional disposal. Over-
dredging (removing more material than
required) must be minimized. The
dredging and support equipment must be
able to efficiently reach each dredging site,
for example, upstream of the Chelsea
Street Bridge.
5.1.2 Physical Limitations
The project site is an active harbor with
extensive commercial vessel traffic. About
two deep draft commercial vessels per day
transit the channel reaches, both entering
and leaving the harbor. These vessels
typically maintain minimum bottom
clearances when transiting fully loaded.
Water velocities, generated by the
propeller wash of transiting vessels of this
kind, and by that of assisting tugs, can be
of sufficient magnitude to resuspend
unconsolidated bottom sediments.
Studies have shown the resuspended solids
may move 300 - 400 feet during these
events. It is anticipated that granular
material will move much less and that in
areas such as the Inner Confluence where
there are the highest instances of propeller
wash material to be blasted during the
project may be used. Dredging operations
will be performed at exposed open water
locations as well as at confined nearshore
berthing facilities. Floating equipment
must minimally impact normal commercial
vessel operations (being easily moved
when required). Dredging equipment will
be adequately sized to operate within
confined berths.
Channel deepening, particularly within
limited reaches of the Mystic River and
Chelsea Creek, could affect the stability of
bulkheads and pile supported structures
situated along the edge of the channel
section. Preliminary studies have indicated
no stability concerns but the contractor will
be directed to make his "box cut" (vertical
sides) well inside the channel limits. In
addition, the project site is characterized
by numerous utility crossings. These
facilities will be identified and protected
during the dredging and rock removal
operations. Dredging operations will be
performed in the vicinity of commercial
and residential structures. Construction
noise is not anticipated to be a major
problem.
5.1.3 Turbidity
There are three primary causes for
turbidity levels to exceed those of
background during the proposed dredging
and material disposal operations:
5-2
-------
Turbidity generated by dredging operations
is typically due to: (1) the impact and
subsequent removal of the bucket from the
bottom; (2) spilling fine sediments from
the bucket as it is hauled through and out
of the water column; and (3) from
disposal and capping operations when the
dredged materials are dumped from the
transport scows into the disposal site.
Turbidity generated by the dredging
operation can be minimized by the careful
control of the rate of dredging. Minimizing
the swing speed and cutter rotation speed
of a hydraulic dredge will generate
minimum resuspension of bottom
materials. Mechanical dredges will be
fitted with closed environmental buckets
which minimize the quantity of material
which is lost from the bucket as it is
hauled through the water column. Slower
bucket cycling rates will reduce the
turbidity generated by mechanical
operations. Use of sensors to confirm full
bucket closure is also anticipated.
5.1.4 Trash and Debris Management
Dredging operations may encounter a
variety of trash and debris especially in the
berth areas. Removal of these materials
will typically be performed by the on-site
dredge. Small items such as rotted timber,
miscellaneous wire rope, cables, crushed
drums and barrels, and items typically
smaller than the excavating bucket will be
removed with the bottom sediments and
placed into the dump scow. These
materials will be placed at the designated
disposal sites as part of the normal
disposal operation. Larger materials, and
any items which may demonstrate a
potential health or safety issue, will be
specially handled. Large timber piles,
vessel hulks, discarded vehicles,
unidentified drums, and similar materials
will be segregated from the bottom
sediments for eventual disposal at upland
sites.
Floating debris, resulting from the
dredging or debris removal operations,
will be skimmed from the water surface
and placed into containers on the dredge or
support barge. The dredging contractor
will be required to develop and administer
a Corps approved Debris Management
Plan. This plan will require that the
designated landfill facility be approved and
that all load manifests be submitted to the
Corps Contracting Officer. Contingency
plans will be developed for managing any
excavated containers with unknown
contents or identified hazardous materials.
5.1.5 Compatibility with Disposal
Contaminated silts, dredged from the
project areas, will be placed at designated
in-channel facilities. Suitable granular
parent material if available or imported
sand material will be used for in-channel
capping of the silts. Parent material not
suitable for capping will be disposed of at
Massachusetts Bay Disposal Site (MBDS)
and/or transported to marine facilities for
off-loading by others to stockpiles for use
such as daily cover for landfills,
construction fill, or other beneficial uses.
Presently, there has been no indication of
possible quantities to be used at landfills.
Excavated rock will be processed and used
as a thin armoring layer (6 - 12") over the
in-channel disposal facility sand cap where
5-3
-------
required due to high bottom velocities
generated by propeller wash. Any surplus
unprocessed rock will be transported to
MBDS and/or to marine facilities for
stockpiling and additional beneficial use.
The transport distances for the parent
material and rock will vary between
several hundred yards to about 30 miles,
depending upon the location of the disposal
or off-loading sites.
Mechanical dredging will remove the
bottom sediments with minimal change to
the material water content. Transport of
the mechanically dredged materials by
bottom dump scows, and possibly barges
for rock, will minimize the volume of
water and material to be transported.
Hydraulic dredging operations which
would require the management and
possible treatment of large volumes of
water which would be transported through
floating pipelines with the dredged
materials. Rock would not typically be
transported by hydraulic pipelines. Scow •
transport of the dredged material can
accommodate the varying haul distances
which are anticipated for the project.
5.1.6 Dredge Types
The proposed dredging will be performed
only by proven equipment, utilizing
demonstrated techniques. Three basic
types of dredges are readily available. The
following paragraphs briefly describe each.
5.1.6.1 Mechanical Dredge
Mechanical dredging uses equipment such
as clamshell dredges, dipper dredges,
draglines, grab buckets, as well as barge
mounted excavators for the removal of
bottom sediments and other materials. The
dredged material removed by mechanical
methods is typically high in solids content.
Removal of the mechanically dredged
material from the dredge site requires
placement of the material in scows or on
barges and transportation to the disposal
area. The dredged material must be
dumped, slurried, or mechanically re-
handled for placement into the disposal
facility. The mechanical dredge can leave
an irregular bottom and typically generates
relatively high levels of turbidity
throughout the water column unless special
closed "environmental" buckets are used
and/or silt barriers are installed.
Mechanical dredges are rugged and highly
reliable and capable of removing a broad
range of materials, including
unconsolidated silts, consolidated clays,
sand, gravel, trash, and debris. Such
equipment is able to operate in the open
channel as well as within confined berth
spaces. Barge or scow transport of the
dredged material is efficient over long haul
distances. Mechanical dredging
productivity is generally low, when
compared to hydraulic dredging
operations, due to the depth of excavation
and to scow loading operations. Such
operations are subject to spillage and
splashing, which allows sediments to
resuspend in the water. Recent
innovations in dredge bucket design have
improved the ability to minimize turbidity
caused by mechanical dredging operations.
5-4
-------
5.1.6.2 Hydraulic Dredge
Hydraulic dredges operate using a solids
handling centrifugal pump to transport
dredged sediments through a pipeline. The
dredged materials are hydraulically
transported as a slurry from the dredge to
a disposal site. The slurry can also be
placed in barges for removal to the
disposal site. The simplest form of
hydraulic dredge, the plain suction dredge,
removes unconsolidated bottom sediments
through a tube which extends from the
suction intake of a barge mounted pump to
the channel bottom. The dredged slurry is
pumped via pipeline to a stockpile or
disposal site. The most significant
improvement to the plain suction dredge is
the addition of a mechanical cutterhead on
the intake side of the suction tube. On the
cutter-suction dredge, the suction head is
fitted with a rotating open basket which
includes blades or cutting teeth to remove
the bottom materials and facilitate intake
into the suction tube. As the cutter rotates
and mechanically removes sediments from
the bottom, a high velocity water flow
captures the sediments and carries them as
a slurry into the dredge suction. The
cutter-suction dredge is versatile and
highly efficient, and is available in a broad
range of sizes to meet the demands of
various size projects.
The hydraulic dredge is typically moved
into position by a tug or push boat and
stabilized by a spud system. The dredge
typically uses three spuds or legs which
pass through the deck barge and can be
raised and lowered to the channel bottom
to firmly hold the horizontal position of
the dredge. The dredging operation
consists of a lateral swing, controlled by
anchor cables, of the cutterhead as the
dredge barge pivots on a single spud. As
the cutterhead swings from side to side,
bottom material is excavated and pumped
by the dredge. The dredge advances
through the dredging reach by lowering a
second stern spud following completion of
a lateral swing. The first spud is raised,
and the dredge is pivoted on the lowered
spud in a walking fashion..
Bottom materials, excavated by the
cutterhead and entrained by the suction
intake, are pumped through a hydraulic
pipeline from the dredge to a disposal-site.
Hydraulic dredges are able to excavate a
broad range of materials. Turbidity,
generated by the cutterhead, is typically
limited to the immediate vicinity of the
bottom intake. Turbidity is managed by
controlling the cutterhead rotation speed,
the swing speed of the dredge, and by
implementing operational controls.
Hydraulic dredges require the use of a
floating or partially submerged pipeline
which can obstruct navigation and restrict
channel use. Hydraulic pipelines typically
require in-line booster pumps to extend
pumping distances and are thus restricted
by practical and economic constraints.
Hydraulic pipeline transport of dredged
materials requires the use and entrainment
of large volumes of water, typically
between 3 and 5 times the in-situ dredging
volume. Management of this water
typically requires extensive facilities for
processing when dealing with contaminated
sediments.
5-5
-------
5.1.6.3 Hopper Dredge
to carry only partial loads, with relatively
high water content, to the disposal site.
Hopper dredges are self propelled floating
ships which include an integral suction
pipe or several suction pipes which are
dragged along the channel bottom. The
bottom materials are drawn through a
suction head on the drag arms and passed
through the suction pipe and centrifugal
pump and deposited, as a slurry, in a large
onboard hopper. After loading, the hopper
dredge can sail to an offshore or other
designated dump site and open bottom
doors and discharge the dredged materials.
Some hopper dredges have the capacity to
off-load the dredged materials by pumping.
Hopper dredges are able to operate in sea
conditions which would severely restrict
the safe operation of other types of
dredges. In addition, hopper dredges
present a minimum interference to other
vessel operations when working in busy
channels and are able to efficiently
transport dredged materials over short haul
distances. However, disposal of the
dredged materials requires that the
dredging process be temporarily suspended
as the dredge travels to the disposal site.
Hopper dredges are typically more
effective when dredging in deep channel
projects and are not effective in restricted
areas such as berths and docking facilities.
Hopper dredges have high production
characteristics when dredging loose alluvial
soils and unconsolidated sands, but are
severely restricted by stiff clays and
similar bottom materials. Very fine silts
are easily dredged by hopper vessels, but
such materials do not readily settle in the
onboard hoppers. This requires the dredge
5.1.7 Rock Excavation Equipment
The BHNIP will include the removal of
about 88,000 cubic yards of rock from
various locations throughout the project.
Specialized equipment, in addition to that
required for the dredging activities, will be
required for rock removal. Removal of
unweathered rock from those areas which
require increased depths will require pre-
treatment prior to removal. This will
include drilling and blasting of the rock
formations. After removal of the silt and
parent material overburden by dredging,
the rock will be drilled. Removal of the
overburden will allow the blasted rock to
•expand and fracture. This will make
excavation more efficient.
Drilling is typically performed by a series
of barge mounted drilling rigs, which will
bore holes of pre-determined diameter and
depth and in a specific pattern in the rock
formation. The drilling barge is moved by
an assisting tug or push boat and held in
position by an anchoring system. An
ancillary barge will likely be used to carry
and store explosive materials. The drilled
holes will be packed with precise quantities
of explosive, which will be detonated hi
order to fracture the rock and facilitate
removal.
The fractured rock, broken into
manageable size pieces by the blast, will
be removed by traditional mechanical
dredge equipment using special rock
handling buckets. The dredged rock will
be handled in the following three ways: (1)
5-6
-------
loaded into scows or on to barges for
transport to either MBDS, or; (2) used as
armoring layer over the cap for in channel
disposal, or; (3) transported to marine
facilities for off-loading to an upland site if
the contractor presents a plan to the Corps
for approval of the upland site.
5.1.8 Recommended Dredging Equipment
and Performance Criteria
The selection of dredging equipment
required factoring in all of the above
considerations to be certain equipment will
be capable of performing as required. In
addition, the dredging operation will be
continuously monitored to assure that
specific minimum performance criteria are
met which also affect the selection of
dredging equipment. Those criteria will
include, but not necessarily be limited to:
• Verification of dredging depth by
periodic digital hydrographic
soundings performed in accordance
with Corps Class 1 standards,
requiring accuracy to 0.5-ft.
• Verification of dredging location
by periodic surveys performed in
accordance with Corps Class 1
standards, which will require
horizontal accuracy to within
3.0-m.
It will be the responsibility of the dredging
contractor to assure that these criteria are
satisfied. Independent verification of
compliance with the critical operating
criteria by the Corps Contracting Officer
will assure that the project will proceed in
a responsible manner. Results of these
compliance reports will be made available
to designated third parties, as appropriate.
5.1.8.1 Recommended Equipment
Dredging will be performed throughout the
BHNIP site by barge mounted mechanical
equipment. This equipment will provide
continuous and reliable service for the
entire duration of .the project. The
mechanical dredge can be fit with different
types of buckets to optimize dredge
production in the various materials which
will be encountered. This dredge plant will
be capable of operating in both the open
channel sites as well as within the
restricted berth areas. Dump scows will be
used for hauling and placement of the
dredged materials. Scows will also be used
for temporary storage of silts during the
initial phase of construction, while in-
channel disposal facilities are under
construction.
Hydraulic or hopper dredging operations
are not recommended for the BHNIP for a
number of reasons. The hydraulic dredge
was not the preferred alternative because it
would require a long pipeline system
which would be a potential obstruction to
navigation. There is no readily available
area for construction of a facility to
dewater the silt material and manage the
high volumes of entrained water. Hopper
dredging operations are not recommended
because of the restricted operating areas
and the anticipated difficulty of dredging
the consolidated parent material.
However, the Corps will entertain a
contractor's suggestions for limited use of
either hydraulic or hopper dredging
equipment particularly hi regard to in-
5-7
-------
channel disposal where water entrainment
would not be as great a concern.
Optimum production of the recommended
mechanical dredge will require the use of
as large a bucket as possible. Bucket size
and type depend upon the available power
on the dredge and the type of material to
be excavated. Silts will be dredged using
a sealed "environmental" bucket with a
capacity of 15 - 22 cubic yards. The
dredge crane will require between 1,500
and 2,000 horsepower. The
"environmental" bucket has been
successfully used to roinimize turbidity in
the immediate vicinity of dredge sites. The
bucket is specifically designed to reduce
sediment loss during closure, and rubber
seals minimize the loss of fines as the
bucket is drawn up through the water
column. Parent material will be dredged
using a heavier standard open bucket. The
increased weight and digging teeth of a
standard bucket will efficiently excavate
these non-contaminated consolidated
sediments with minimal loss of material
through the water column.
Scows and barges will vary hi size
depending upon availability and location of
the dredging operation. Dredged material
scows typically range in size from 500 cy
to 4,000 cy. It is anticipated that smaller
scows will be used in the confined reaches
of the project such as the berth areas.
Larger scows will be used in the open
channel reaches. The scows will be moved
from the dredge sites to the disposal sites
by tugs. Small harbor tugs, with on-board
power of around 1,500 hp, would be used
to transport the loaded scows to disposal
sites within the channel area. Loaded
scows, which transit exposed areas, will
require the assistance of larger 3,000 hp
ocean-going tugs.
The project volume is sufficiently large
and the required work areas are so broadly
spread out, that it is expected that the
dredging Contractor will employ two (2)
dredges. During the period when dredging
is to take place in the Mystic River both
dredges could work in different areas of
the river and not interfere with each other.
At other times, one dredge would work in
the Reserved Channel and one dredge
would work hi Chelsea Creek.
Additional equipment which might
typically be on site will include a fuel
barge, a maintenance barge, and a small
work tug to assist with moving the dredge
and scows. Rock excavation will be
initiated once the silt and parent material
is removed and the rock is exposed.
Special equipment associated with these
operations is described in Section 5.2.4.
5.1.8.2 Operational Controls
The dredging operations, including the
required drilling and blasting; can be
managed sufficiently to minimize the
associated environmental impacts. The
principal objective of defining and
implementing operational controls on the
construction activities is to minimize
sediment resuspension throughout the
dredging process while maximizing
operational efficiency. The drilling and
blasting operations present an additional
control challenge. Pressure wave
propagation resulting from blasting can
injure and kill fish. Specific blast control
techniques must be incorporated into the
5-8
-------
dredging program. The specific control
methods which are employed will be
dependent upon the dredging techniques
which are implemented. Control
techniques, demonstrated on other sensitive
dredging operations, may include the
following:
• Restricting the bucket drop
velocity and haul speed during
mechanical dredging.
« Employ a sealed "environmental"
bucket as described hi previous
sections.
« Employ fish behavioral and control
devices to reduce exposure to
blasting areas.
* Contractually require that the
dredging, disposal, and blasting
operations meet specific minimum
environmental performance
standards and environmental
windows.
• Include, as part of the contract
documents, the requirement for
submittal and implementation of
project specific: Accident
Prevention and Site Emergency
Plan; Environmental Protection
and Turbidity Control Plan;
Quality Control Plan; and Diving
Plan.
* Require the dredge operators) to
meet specific minimum
competency and experience
requirements.
Notify lobster fishing interests of
dredge movements.
5.1.8.3 Contract and Specification Issues
Contract documents are used to clearly and
equitably define the expectations and
requirements of both the Corps'
Contracting Officer and the Contractor for
the successful completion of any
construction project. A similar effort is
expected between private berth owners and
their contractors. The BHNEP contract
documents will define the quantities,
locations, and types of materials to be
dredged. The required location and
elevations of the dredged material, after it
is placed at the in-channel disposal
facilities, will be clearly defined. Proper
location, materials, and acceptable
tolerances for the disposal facility capping
system will be clearly defined hi the
drawings and specifications for this
project.
The project will be executed by the
dredging contractor under the terms of a
performance based contract. This means
that the operation must satisfy specific
performance standards during all
operations. Dredging must be performed to
the lines and grades defined on the design
drawings and must be performed in such a
manner as to control turbidity levels. If
these criteria or standards are not
achieved, the Contracting Officer will be
obligated by contract to require the
Contractor to alter the method of operation
or cease operations until the required
standards are met. The contract
documents will clearly identify the
procedures to be implemented by the
5-9
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Contracting Officer in the event that the
performance criteria are not met.
The Contracting Officer has the
responsibility to enforce all terms of the
contract and has the sole authority to direct
the Contractor to alter or cease operations.
It is anticipated that the Contracting
Officer would secure the services of a
qualified subcontractor to monitor the key
performance criteria. It is likely that the
dredging Contractor would simultaneously
monitor those criteria to optimizing the
operation and to demonstrate project
quality assurance. Daily performance
reports from the monitoring subcontractor
will keep the Contracting Officer apprised
of the operation performance. These
reports would be available to interested
parties.
5.2 DREDGING OPERATIONS
Orchestration of a large dredging project
such as the BHNIP will require careful
planning by a team made up of the US
Army Corps of Engineers, Massport, State
and Federal regulatory agencies, the
dredging Contractor and critical Sub-
Contractors, and public and commercial
interests hi and around Boston Harbor.
The specific operations to be performed as
part of the BHNIP are diverse, but all are
directed at completing the project in an
efficient and responsible manner. The
following sections describe the specific
operations.
5.2.1 Project Mobilization
Prior to the initiation of actual dredging, a
number of preparatory tasks must be
completed. The completion of these
mobilization tasks will set the foundation
for the efficient execution of the contract
work.
5.2.1.1 Upland Support Requirements
Dredging and rock excavation operations
will require an upland support area with
direct access to the Harbor. It is
anticipated that such a support facility can
be provided at a Massport facility. It is
possible that such sites could be used to
support simultaneous activities in different
parts of the Harbor. The upland support
facility must provide sufficient vehicle
parking for all of the project personnel.
Temporary project trailers, including office
facilities and enclosed material storage
facilities will be placed at this site. Marine
support equipment, such as personnel
transports, survey vessels, tugs, and other
craft will berth at this location. Repairs to
both floating and support equipment will
be performed at this staging area. These
sites could also be used for temporary
sediment dewatering facilities hi the event
that volume restrictions limit the quantity
of material that can be placed at the in-
channel disposal sites. However, neither
of the dewatering sites would be large
enough to handle the dewatering of all silt
materials. Experience with dewatering of
dredged material at Moran Terminal
suggested use of thin lifts for air drying
which would require acreages up to 80
acres.
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5.2.1.2 Navigation and Commercial
Traffic
Scows of various sizes will be used to
transport the dredged materials from the
dredging sites to the disposal facilities.
Silts will be disposed at in-channel
locations throughout the Inner Confluence,
Mystic River, and Chelsea Creek. The silts
will be capped with suitable parent
material or sand which will be hauled
within the Harbor in scows (see paragraph.
5.2.2.4). Excavated rock will be processed
and placed from barges or scows on top of
the sand cap as armoring to resist
resuspension of the sand by the propeller
wash of passing deep draft vessels. .It is
anticipated that two dredges-will be
simultaneously working in various sections
of the Harbor during the project term.
Modeling has shown that Federal water
quality standards would not be violated.
All commercial and recreational marine
interests in Boston Harbor must be fully
informed of the potential interference with
normal traffic by the dredging equipment.
Vessels will be required to navigate safely
around the equipment. Larger commercial
vessels will require special procedures to
coordinate 'movement of the dredging
equipment and securing of the disposal
operations to allow passage through the
channel.
Blasting operations will be performed hi
the Mystic River channel, the Inner
Confluence, at the mouth of the Reserved
Channel, and hi the Main Channel east of
the Reserved Channel. Vessel operators
must be warned of all blasting operations.
Blasting schedules will be provided to all
commercial operators. Vessel movements
will be regulated by the US Coast Guard
during actual blasting activities.
5.2.1.3 Structural Evaluation
Prior to dredging or blasting operations, a
detailed survey of existing infrastructure
will be performed. This survey will
include a review and documentation of the
harbor structures that may be impacted by
the proposed activities. The location of
critical structures will be determined and
recorded on control documents. Structure
condition will be described and a
photographic record will be made. Pre-
project conditions will be clearly
identified. A condition report of each
structure will be prepared by the blasting
contractor and provided to each facility
owner prior to any construction activities.
A survey of the existing channel and berth
areas included within the project bounds
will be performed to identify and locate all
submarine utilities. The survey will
encompass a review of record drawings
maintained by utility companies, including
but not necessarily limited to: Boston
Edison Company; Metropolitan District
Commission (MDC) Water and Sewer
Divisions; Boston Gas Company;
Massachusetts Water Resource Authority;
and private marine facilities. The survey
will identify the location of all utility
elements and will identify specific means
for protection or relocation during the
dredging and/or blasting operations.
5.2.1.4 Regulatory Constraints
AH construction activities related to the
dredging of silts and parent materials and
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the removal of rock from the project area
and thin disposal will be performed under
the conditions established within the
permits issued for this work. These permit
documents may identify specific
environmental performance criteria which
must be satisfied. Berth areas will require
individual permits with a special condition
that vessels moored at the berth shall not
extend into the federal channel.
5.2.1.5 Seasonal Limitations
The movement of anadromous fish will
require the limitation or stopping of
dredging activities in the Mystic River and
Inner Confluence during the spawning
period between 1 February and 15 June.
Blasting will also cease during that period.
If agreeable to the State regulatory
agencies, monitoring may be conducted to
determine if dredging and disposal can
continue during this tune frame in the
Mystic River and inner Confluence.
g.2.2 Dredged Material Handling
Procedures
The proper handling of dredged material
will assure that potential impacts to the
environment are minimized. The following
sections characterize the general
procedures which will be used throughout
the project.
5.2.2.1 Monitoring Requirements
During dredging operations, activities of
the contractor will be observed by the
Corps on-site construction management
staff. This staff will be directly
responsible to the Contracting Officer. In
addition to monitoring and verifying the
dredge position (particularly important hi
areas of known utility crossings), this staff
will also assure compliance with required
permit conditions.
Specific comments to this DEIS/R
requested independent monitors to be on
the contractors vessels. While the Corps
would not object to an onboard observer,
there are safety and liability issues to be
addressed. The Corps does not typically
fund this type of activity although it does
contract with a dredge inspection firm
which verifies disposal locations for
contract and permit compliance. The
independent observer can alert the Corps
inspector of any perceived permit
violations. However only the Contracting
Officer can modify or halt dredging and
disposal operations.
5.2.2.2 Environmental Bucket
Dredging of the silt materials will be
performed with an enclosed
"environmental" bucket. The bucket is
specifically designed to reduce sediment
loss during closure and is provided with
rubber seals to minimize loss of fines as
the bucket is drawn up through the water
column. There are several manufacturers
of such buckets. The key features of these
proven systems include those design
innovations which minimize the generation
of resuspended sediments during all phases
of the bucket operation.
Traditional buckets remove a concave bowl
shaped cut from the channel bottom,
whereas some environmental bucket
designs make a uniform horizontal cut in
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the sediments. This type of an
environmental bucket enhances the ability
of the operator to make a uniform cut of
the channel bottom without performing
secondary operations, such as dragging of
the bucket to smooth any residual ridges,
which tend to resuspend bottom sediments
and increase turbidity. Modern
environmental buckets include integral
bucket covers which protect excavated
sediments from being washed from the
bucket as it is hauled through the water
column. These covers are included with
purge valves which reduce the effects of
bucket impact during descent through the
water and initial contact with the bottom,
thus further reducing potential
resuspension. Clamshell seal indicator
switches are available to alert the operator
when the bucket has not completely sealed.
5.2.2.3 Dredging Locations
Dredging will be performed in the Federal
channel in the Chelsea Creek and in
portions of the Federal channels in the
Mystic River and Reserved Channel.
Dredging of some private berths, adjacent
to these channels, will also take place. In
addition, several private berths located hi
the project area and located along the main
ship channel will be taking advantage of
me opportunity to dispose of silt material
dredged from their berths at the disposal
sites constructed as a part of the BHNIP.
For a detailed description of the project,
the reader should refer to Section 2.0 of
this document.
5.2.2.4 Facility Construction
Construction of land-based facilities is not
anticipated. Sand used as capping material,
will be loaded at existing terminal facilities
situated throughout the harbor or barged
into the harbor depending on the contractor
source of the sand. Off loading of trash
and debris, which cannot be placed hi the
in-channel disposal cells, will require pier
space for temporary storage and transfer to
an approved landfill. It is anticipated that
the trash transfer operation will be
intermittent and require a relatively small
area. In the event that contingency plans
for upland disposal of a small portion of
the silt materials is required, a dredged
material dewatering operation would be
temporarily established at a waterfront site.
This would only be implemented if the in-
channel disposal storage volume was not
sufficient to contain all of the silt material
and disposal of small volumes of material
at the Little Mystic channel was not
available. The dewatering operation would
consist of either diking or of mobile
mechanical equipment.
5.2.3 Dredging Sequencing
The following paragraphs identify the
mechanism and rationale for determining
the dredging priorities for the BHNIP.
5.2.3.1 Site Prioritization
The location for the start of dredging will
be governed by the tune of year that the
project begins. For example, if the
contractor were to get underway during the
environmental restriction time period, they
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would be directed to work initially in the
Chelsea Creek and Reserved Channel. If
no restriction is in effect, the contractor
will be directed to begin dredging in the
Mystic River. Scheduling for the dredging
and preparation of in-channel silt disposal
cell facilities hi the Mystic River is critical
to ensure a sufficient number of cells
available for disposal of contaminated silt
from the Reserved Channel. If the Mystic
River disposal cells are restricted or ,
prohibited during dredging of the Reserved
Channel, then the Chelsea Creek cells will
be used until such time as the dredge plant
operating hi the Reserved Channel can be
moved to the Mystic River or Inner
Confluence. Use of the Mystic River in-
channel disposal cells for material from the
Inner Confluence and Chelsea Creek may
be necessary to assure availability of cells
for the Reserved Channel contaminated
silt.
5.2.3.2 Material Prioritization
It is estimated that over 1.3 million cubic
yards of dredged material storage volume
will be created during the excavation of
the in-channel disposal facilities. This
volume was estimated by examining the
seismic records made during November
1992 which indicate the subsurface
composition. The depth of subsurface
information was limited to -55 ft (MLW)
hi several locations. However, additional
capacity may be realized if the contractor
is able to dredge deeper than -55 ft
(MLW).
To create the in-channel disposal cells, the
contractor will be directed to dredge as
deep into the exposed parent material as
practical with the equipment available.
Some areas will support excavation to as
much as -70 ft (MLW). The practical
limitations to the depth of dredging will be
dictated by the geotechnical stability of the
dredge cut and by the proximity and
integrity of any adjacent structures.
Dredging too close to a structure or
dredging soils which will slough
excessively may lead to undesirable
structure movement.
It is estimated that the volume of silt to be
dredged is approximately 1.1 million cubic
yards and that it can be expected to expand
to 1.3 million cubic yards as a result of
dredging and handling. It appears that the
in-channel disposal areas will
accommodate the Federal channel silt and
the material to be dredged from the berths
which have been identified as direct
project beneficiaries. Any significant
increase hi dredging volumes and/or
required in-channel disposal volumes will
require that additional disposal capacity be
found during construction. Some of the
remaining material dredged from the
berths could be placed either hi the Little
Mystic Channel or sent to an upland site.
This is discussed further hi paragraph
5.6.2.3 of the Contingency Plan section of
this document. Material dredged from
these berths will receive preference over
non-beneficiary facilities.
5.2.5.3 Schedule
As mentioned in previous sections, the
schedule for dredging will depend upon the
requirement to construct the in-channel
disposal cells prior to dredging of silt
materials. Scheduling of operations will
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include consideration of the restriction of
activities in the Mystic River and Inner
Confluence during 1 February to 15 June
due to expected environmental limitations.
It is anticipated that Federal funding will
allow the BHNIP contract to be bid during
the winter of 1996-1997 with award and
"notice to proceed" expected during the
early spring of 1997. The contractor
would be directed initially to construct in-
channel disposal cells in the Chelsea
Creek. A portion of that work will require
the dredging and temporary storage of
approximately 9,000 cy of silt in scows.
Dredging of contaminated silt in the
Reserved Channel would start as soon as
the Chelsea Creek in-channel disposal
cell(s) were available to receive material.
As soon as dredging is able to commence
in the Inner Confluence and Mystic River,
the contractor will be directed to transfer
the dredging operations to those sites.
Dredging must take place in the Mystic
River and Inner Confluence throughout the
entire available environmental "window".
The contractor would proceed with
dredging and construction of in-channel
disposal facilities hi the Mystic River and
Inner Confluence until those reaches were
completed. These operations would be
terminated if they were not completed
before the following environmental
restriction period. It is possible that a
dredge operating hi the Mystic River or
Inner Confluence would have to be moved
to the Chelsea Creek to prepare in-channel
disposal cells for use during the restricted
period. These flexible operations may be
necessary to maintain continuity and to
keep the project on schedule. This would
mean Chelsea silt would be disposed in the
Mystic River rather than its own river bed,
thus creating cells to be used later.
5.2.3.4 Limitations
Since in-channel disposal cells will be
constructed by dredging silt and then
parent material, an obvious limitation to
the continuity of operations is that of not
having in-channel cells available when
needed for disposal. If silt can not be
placed hi the disposal cells, then parent
material cannot be dredged, thus
effectively stopping construction of
disposal cells. The construction
management team will be responsible for
assuring that in-channel cells are always
available for contaminated silt disposal.
As a contingency, a limited quantity of silt
material could be temporarily stored on
scows until parent material can be removed
and the disposal facilities made available.
When working in the Chelsea Creek and
Reserved Channel, each cell constructed
above the Chelsea Street Bridge will store
an average of 31,000 cy of silt.
Approximately 9,000 cy of that material
will have been dredged hi the process of
creating the disposal cell facility.
Therefore, silt brought in from dredging of
the Reserved Channel will require careful
monitoring to avoid exceeding the cell
capacity in the Chelsea Creek. It may be
beneficial to delay dredging hi the
Reserved Channel until sufficient cell
capacity exists in the Chelsea Creek.
Dredging operations will be performed hi
active commercial channels. The dredging
Contractor will be required to
accommodate the passage of vessel traffic.
Since the Chelsea Creek channel is
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relatively narrow, the contractor will need
to periodically shut down the dredging
operation and move out of the channel to
let traffic pass.
Ship Channel at the mouth of the Reserved
Channel. The remaining 54,000 cy of rock
will be taken from the Inner Confluence
and Mystic River Channels.
5.2.4 Blasting and Rock Removal
Significant volumes of rock will need to be
removed from several areas for the
BHNIP. Silt and parent material will first
be removed by dredge from the specified
areas to expose the underlying rock.
Holes, drilled hi the rock by barge
mounted drill rigs, will be filled with
explosives. Vessel traffic will be cleared
from the area and the explosives will be
detonated, resulting hi loose fractured rock
that will be dredged by mechanical means.
The excavated rock will be placed hi
scows or on barges for transportation to an
unconfined disposal site, used as an armor
layer for the sand cap, or used for
commercial purposes. If the rock is used
for upland commercial purposes, truck
traffic can be expected to be moderate
since production of the blasted rock will
occur at different periods during the
construction of the project. At present,
there is no known commercial use for the
rock.
5.2.4.1 Locations
Approximately 88,000 in-situ cy of rock
will be removed from the mouth of the
Reserved Channel, the Inner Confluence,
and from the Mystic River Channel. All of
the rock is located within the Federal
Channel reach. It is estimated that 34,000
cy of rock will be blasted and dredged
from the maneuvering areas of the Main
5.2.4.2 Seasonal Limitations
The same seasonal limitations described in
Section 5.2.1.5 apply to rock removal
operation.
5.2.4.3 Mitigation
In addition to imposing seasonal
restrictions upon the blasting operations,
specific mitigation techniques will be
employed to further reduce the potential
impacts of blasting. Fish behavioral or
other devices will be used to startle,
frighten or deter fish from the blasting
area during operations. Sonic startle
devices or pneumatic bubble barriers will
be evaluated as fish deterence devices to
induce fish to leave the critical area and
thus reduce mortality.
53 DREDGED MATERIAL
DISPOSAL OPERATIONS
The following sections describe the general
operations associated with disposal of the
dredged materials. These descriptions
focus primarily on the anticipated in-
channel operations.
5.3.1 Equipment and Facilities
The basic equipment which a Contractor
would use for in channel disposal
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operations will likely consist of a tug and
nominal 3,000 cy scows. At least two (2)
scows will be used to service each
operating dredge.
Parent material will be transported by rug
and scow to the MBDS. The tug must be
of sufficient size to control a 3,000 or
4,000 cy scow on the open sea in all types
of weather. A minimum of two (2) scows
for each dredge will be required since the
round trip tune to the MBDS is about 8 -
10 hours. One scow will receive dredged
material as the other is transported
offshore for dumping. The disposal site
will be identified by a buoy and each tug
will have onboard a dredge inspector to
verify disposal location.
5.3.2 Impacts on Dredging Operations
The difficult scheduling requirements
created by the in-channel disposal option is
expected to impact the dredging operation.
The frequent changing of buckets will
probably take place during the time scows
are being shuffled and taken away for
disposal. The dredge will need to cover
the same area of channel at least twice -
once for silt material and once for parent
material. While dredging the parent
material, the dredge will remain in one
location longer because more parent
material will be removed per area to create
disposal space.
5.3.3 Weather Restrictions
Disposal operations will be affected by
both weather conditions and environmental
restrictions. Disposal of parent material at
the MBDS requires exposure to the
sometimes harsh New England weather
particularly during the whiter months when
cold temperatures and Nor'easter storms
confront the towing vessel's crew. Tug
captains will have the final say as to
whether they will risk making disposal
trips in stormy weather although the
Contracting Officer's representative may
direct against venturing out in rough seas.
Typically, contract specifications allow for
weather related delays.
Another type of weather related restriction
to the disposal process will be the.volume
of vessel traffic on the Mystic River and
Chelsea Creek. Whiter weather will bring
an increase in fuel deliveries to distributors
on both of these rivers. Dredging and
disposal operations will need to move
equipment to let tankers pass. Because of
the relatively short tune for disposal, the
delay caused by increased vessel traffic is
not expected to be as great on the disposal
operation as it would be on the dredging
operations.
5.3.4 Capping Operations
Capping will be employed to isolate the
silt material placed in the in-channel sites.
The cap will be designed to act as a barrier
during future maintenance operations,
preventing the dredge bucket from
penetrating into the disposed material.
The DEIR/S contemplated use of parent
material for capping. During discussions
with state agencies it became clear that use
of the predominantly clay parent material
for capping was unacceptable due to
unresolved concerns over the ability of the
highly cohesive clay to spread out over the
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cells to minimize voids in the cap.
Another area of concern was the ability of
the silts to support the clay cap. Finally,
the constructability concerns regarding the
ability to meet the tight tolerances required
in the navigation channels (-42 feet MLW)
with highly cohesive material, eliminated
the use of clay as a capping material for
the in-channel locations. Therefore, sand
or granular parent material will be used for
a cap.
The New England Division of the Corps
has performed extensive capping projects
and monitoring of capped disposal areas,
primarily in Long Island Sound. An
extensive capping and monitoring
bibliography in included in this FEIR/S in
the references section found in Chapter
Nine. As part of their studies, the Corps
obtained core samples from a variety of
disposal sites in the Long Island Sound.
Analysis of the split cores showed that the
cap and contaminated material interface
was easily discernable in most cores.
More importantly, a mixing zone of less
than 10 cm (approximately 4 inches) was
observed. This zone was identified by a
boundary signature appearing hi the
chemical analyses that were performed on
the cores at 20 cm intervals. The
contamination profile of the sediments
below the cap abruptly changed at the
cap/silt interface to below detection limits
within the cap material (see Figures 5-1
and 5-2).
Although the contractor will be required to
develop a specific method for placing a
nominal 3-feet of granular capping
material; it is generally understood that the
cap material will be spread on individual
cells as filling with silt is completed.
Spreading the cap materials will be done
by partially opening the doors on split
hulled scows and gradually releasing sand
as it moves over the cell. A survey of the
trench will be required prior to placement
of the cap. The contractor may be
required to drag a heavy beam along the
top of disposed silt prior to placement of
the cap to prevent the cap from protruding
above the -42 ft (MLW) datum and to
maintain cap thickness as uniform as
practicable. If imported sand is required,
it will be loaded onto scows at a harbor
facility. A final survey will be required
after capping is completed to verify
operating depths.
5.4 CONSTRUCTION SEQUENCING
5.4.1 Dredging and Disposal Sequencing
Construction of the BHNIP will require
about 18 months. This will vary
depending on the contractor awarded the
job and the job and the equipment brought
to the job. Because of the length of tune
over which the dredging will take place,
the restricted dredging period (to protect
anadromous fish runs) in the Mystic and
Inner Confluence will impact on project
scheduling. It is assumed that a contractor
will use two dredging plants in order to
minimize dredging time. However, this
complicates the scheduling of dredging
locations and production rates. A detailed
example scenario using two dredges has
been worked through and is included in
Appendix J and is summarized on Figure
5-3. This scenario is only to serve as a
guide and to show that the sequencing can
work. A contractor will probably modify
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the sequencing to meet equipment and
weather needs.
The primary goal of scheduling is to keep
both dredge plants in full production at all
tunes. Another objective is to minimize
storing silt in scowstoarges. Cells must be
ready to accept silt material when silt
material is being dredged. Initially silt
will be stored in scows while the first cell
is being prepared. Depending on the
number of scows available for storage, the
initial cell may be smaller than suggested
in the scenario. However, as long as the
storage cells are dug deep enough there
will be adequate capacity for the silt
removed from the top of the cell and
several adjacent cells. Once a cell is
prepared it typically will have capacity to
store about three tunes the silt removed to
create the cell. In this fashion, the
contractor can "get ahead" or fill cells
with material from another tributary or
berth.
The example scenario which has been
worked through, begins in April (year 1)
when dredging is expected to be prohibited
in the Mystic and Inner Confluence. A
single dredge plant would begin just
upstream of the Chelsea Street Bridge and
begin creating cells progressing upstream.
By early May, three cells should be
prepared and a second dredge plant begins
in the Reserved Channel. As the Chelsea
dredge continues to create four more cells
by mid-June, the Reserved dredge has
alternated between dredging silt and parent
material as cell capacity is created in the
Chelsea.
In mid-June the dredge working in the
Chelsea Creek moves to the Mystic River
just upstream of the Tobin Bridge.
Likewise, the dredge from Reserved
Channel moves to the Inner Confluence.
Silt produced by both dredges is initially
sent to cells in the Chelsea Creek until
cells are prepared in the Mystic and Inner
Confluence. Once cells are established hi
the Mystic and Inner Confluence, the
process of creating cells and disposing silt
in these areas will continue until the end of
January (year 2) in the Mystic and the end
of November hi the Inner Confluence. It
should also be noted that berth owners
must arrange to have the berths dredged at
the appropriate time. This scenario
assumes the owners will contract with the
Corps' contractor who is on site and will
be able to adjust berth dredging to
accommodate disposal cell availability.
By the end of November, the dredge
working the Inner Confluence has
completed all cells and dredged all
berthing areas of both silt and parent
material, that dredge will then move back
to the Reserved Channel and produce silt
for cells hi the Mystic. This dredge will
be finished producing silt near the end of
December and will proceed to remove
parent material and rock from the
Reserved Channel. This dredge will be
demobilized when finished with the
Reserved Channel early hi March.
Meanwhile, in late January, the dredge
working in the Mystic River will move
back to the Chelsea Creek to continue
where it left off and will ship its first cell's
silt back to the Mystic. After completing
the upstream cells, the dredge will move to
the Lower Chelsea Creek. No cells would
be created below the Chelsea Street Bridge
during the initial improvement project.
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This area would be available for future
maintenance dredging operations. It
appears the dredge may finish in the
Chelsea Creek about mid-May and cannot
return to the Mystic until mid-June.
Between mid-June and the end of October,
the dredge will finish creating cells and
dredge the berths hi the Mystic and any
rock removal necessary.
Since scheduling is subject to change daily
due to weather conditions or equipment
problems, there may be times when silt
may have to be stored on scows as done
during the initial dredging. Dredging may
be required to slow down hi order to meet
an environmental requirement or it may
become necessary, provided regulatory
agencies permit it, to work into the
environmental window in the Mystic and
Inner Confluence.
5.4.2 Project Demobilization
Following completion of the dredging and
disposal operations, all equipment and
personnel will be demoblized from the site.
A final survey will- be performed to
determine the post-dredging bottom
conditions. Final drawings, which show the
location and depth of all material placed at
the in-channel disposal facilities, as well as
the location and depths of the cap system,
will be prepared. A post-construction survey
of all potentially impacted infrastructure will
be performed to determine the extent of
damage which may have resulted due to the
dredging and/or blasting operations. This
survey will include a review of claims which
may have been made by structure and utility
owners. Any temporary utility relocation or
protection works which may have been
installed prior to dredging will be removed.
If damage is detected, it will be me
contractor's responsibility to repair the
damage. The project must have been
completed according to specifications before
it will be accepted by the Contracting
Officer.
5.5 SUMMARY OF CONSTRUCTION
MITIGATION
This Plan has identified specific techniques to
be employed during the various critical
operations throughout the project which will
minimize impacts of the project. The
following sections summarize these
recommended actions.
5.5.1 Dredging
Dredging operations will be required to meet
specific performance criteria during all
activities. Removal of contaminated silts will
be performed with a closed "environmental"
bucket with a capacity between 15-22 cy.
which has been proven to reduce turbidity
levels resulting from dredging operations.
One of the most effective mitigation
measures which could be implemented would
be to require the dredge operator to meet
minimum competency and experience
criteria. Operator skill can be exploited to
assure efficient and low impact dredging.
The "environmental" bucket has been
successfully used to minimize turbidity in the
immediate vicinity of dredge sites. The
bucket is specifically designed to reduce
sediment loss during closure and is provided
with rubber seals to minimize loss of fines as
the bucket is drawn up through the water
5-20
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column. Restricting the bucket drop velocity
and haul speed will further minimise the
potential for increased turbidity in the water
column due to dredging. Silt curtains will be
deployed around the dredging and disposal
cells to further minimize turbidity in the
immediate vicinity of the active work area.
All construction activities related to the
dredging of silts and parent materials and the
removal of rock from the project area will be
performed under the conditions established
within the permits issued for this work. It is
anticipated that these permit documents will
identify specific environmental performance
criteria which must be satisfied.
5.5.2 Rock Excavation
Blasting of rock hi the Mystic River and
.Inner Confluence areas where anadromous
fish have been observed will not be
performed between 1 February and 15 June.
Also, appropriate fish deterence devices will
be employed to minimize fish mortality
during blasting.
5.5.3 Dredged Material Disposal
Dredged material disposal will require the
dumping of dredged silts from scows into the
prepared in-channel facilities. Disposal of
parent materials will be at MBDS unless the
material can be beneficially used at an upland
site and the scow can be off-loaded
immediately.
5.6 MONITORING DURING
DREDGING AND DISPOSAL
OPERATIONS
Monitoring during dredging and disposal
may be required to comply with
environmental permits. It will be the
responsibility of the Contracting Officer to
implement and execute these requirements.
The monitoring program if required, will
identify specific minimum performance
criteria which must be satisfied to safely,
effectively, and responsibly complete the
required dredging and associated activities.
Performance criteria may involve readily
quantifiable and measurable parameters such
as turbidity, depth and planar distribution of
deposited sediments.
5.6.1 Dredge Performance
The critical performance parameters which
will be continuously monitored during
dredging operations will include specific
production and performance data and position
verification. Also monitored will be the
amount of parent material mixed hi with the
silt. Too much clay will indicate a change hi
procedure may.be needed to avoid filling the
in-channel cells with clean material.
Dredge performance is quantified by
continuously monitoring the volume of
material removed as a function of time. An
accounting of the number of cycles
performed by the dredging bucket over a
fixed period can form the basis for an
estimate of dredged quantities, assuming the
bucket removes approximately the same
quantity in each cycle. A complementary
technique requires maintaining a count of me
numbers of scows which are filled to me load
5-21
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line and hauled to the disposal site. The
volume of dredged material is approximated
based on the displaced volume of the scow
and me estimated specific weight
and water content of the material. The
estimated volume is typically factored to
account for the increase in volume of the
dredged material as compared to the in-situ
volume.
The volume of each scow is documented and
a cumulative estimated total of dredged
volume is maintained by the Project
Engineer. Periodic hydrographic surveys of
me project site are typically performed to
determine more precisely the quantities of
material dredged from the project site. These
surveys are performed in accordance with the
standards established by the US Army Corps
of Engineers, Engineering Manual No. 1110-
2-1003,28 February 1991. Specific
procedures and acceptable quality control
standards for surveys performed for
construction administration., payment, and
project acceptance are defined in this
universally accepted manual. Volumes will
be determined by a comparison of the pre-
dredge hydrographic survey with the post-
dredge survey. In-place volumetric
differences within the payment prism will be
computed as the difference between those
surveys.
Positioning of the dredge during dredging
operations and maintenance of horizontal and
vertical control during hydrographic surveys
are related critical issues. The US Army
Corps of Engineers, New England Division,
maintains a series of benchmarks throughout
Boston Harbor which provide accurate
references for elevation and position. These
benchmarks, complemented by temporary
control points which reference these
benchmarks, will be used for all survey
measurements. All horizontal positioning will
be referenced to the State Plane Coordinate
System and will be accurate to within 3.0
meters. Depth measurements shall be
referenced to the National Geodetic Vertical
Datum of 1929 (NGVD) and shall show the
local Mean Low Water Datum (MLWD) as
referenced to NGVD. All vertical depth
measurements shall be limited to a standard
error not to exceed 0.5-ft. These
requirements meet the standards for Class 1
surveys.
Disposal activities, such as the positioning of
a scow during dumping operations, will not
ordinarily require the accuracy of a Class 1
survey. Positioning of those scows to within
approximately 5.0 meters will be sufficient.
Monitoring of potential movement of the
dredged materials placed at the disposal sites
will be performed to the more demanding
accuracies required of a Class 1 survey, due
to the need to accurately determine the fate
of the placed materials.
The daily operations of the dredge will
include repositioning of the dredge a number
of times. In addition, the dredge bucket will
be lowered to the bottom and material will be
hauled from the bottom approximately once
per minute. Positioning can be verified by
several methods, all of which satisfy the
accuracy requirements of a Class 1 survey.
These methods include: positioning by pre-
established and surveyed rangelines and
reaches; location by land-based survey
instruments to establish the range and
azimuth of the dredge from a known
benchmark; and positioning by satellite using
a differential Global Positioning System
(GPS). The depth of excavation will be
continuously monitored by the dredge
5-22
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operator using a bucket mounted pressure
transducer compensated for transducer
position and bucket geometry. The operator
will also mark and calibrate the bucket
suspension and closing lines to provide a
visual check of digging depth. The dredge
operator will establish visual and electronic
tide gauges to continuously compensate the
digging depth for water surface elevation
variations.
5.6.2 Environmental Impacts
Potential impacts to water quality will occur
within a relatively constant distance from the
dredging operations. An estimate of plume
size based upon recent models (see Appendix
F) is approximately 500-ft from the dredge.
Mechanical dredging operations can be
expected to result in 3-5% of the total
dredging quantity being brought temporarily
into suspension. It is therefore possible that
contaminants will be released to the water
column as a result of this resuspension. The
difficulty arises with variations across the
project areas hi current, water depths, fresh
water input, CSO discharges, sediment
physical characteristics, and other point
sources which will all contribute to actual
turbidity levels around the dredge site. In
addition, dredging methodologies employed,
such as production rate, barge overflow, and
careful bucket operation, can have an even
greater impact upon turbidity levels at the
dredge site.
5.6.3 Accountability and Supervision
Contract documents will clearly define the
levels of responsibility and lines of authority
for the sponsor, Contracting Officer, and
Contractor. The Contracting Officer will be
designated by the US Army Corps of
Engineers and will be responsible only to the
project sponsor, Massport. The Contracting
Officer will not be responsible for berth
dredging or utility relocations, removals or
production unless a special agreement is
executed between the Corps and Massport.
The Contracting Officer will be responsible
for implementing all terms of the contract
and for assuring that all conditions of the
project permits are satisfied. The Contracting
Officer will employ, at his/her discretion,
various experts to assist with contract
administration. For example, the Contracting
Officer may designate a firm that specializes
hi environmental data acquisition to monitor
water quality at the dredging and disposal
sites. Other specialists, retained to support
the Contracting Officer, could include
licensed surveyors and/or hydrographers to
monitor and verify all dredging depths,
volumes, and critical disposal information
and on-board inspectors to monitor dredge
production and to verify that proper
procedures are employed during disposal
operations.
It is likely that other project experts will be
directly responsible to. the Contracting
Officer. Critical mitigation tasks such as
installation and operation offish behavioral
devices and pneumatic blast wave attenuation
systems are not within the typical areas of
expertise provided by construction
contractors. Successful implementation of
these critical systems can be more reliably
assured if performed by specialized
professional firms directly responsible to the
Contracting Officer.
5-23
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All of the project personnel, including the
dredging contractor, scientists performing
monitoring, mitigation specialists, and others,
wfll be responsible to the Contracting
Officer. The Contracting Officer will
maintain authority over work in the federal
channels. Massport and/or private berth
owners will be responsible for all work
outside of the channels.
5.7 IX)NG TERM MONITORING OF
DISPOSAL SITES
The long term monitoring program for the
selected aquatic dredged material disposal
will be based upon the tiered approach
presented in the Disposal Area Monitoring
System (DAMOS) protocol.1 DAMOS
evaluates impacts to specific targeted
resources to establish a threshold of effects to
the general environment.
Parameters^
The Disposal Area Monitoring System
.(DAMOS) is a program begun in 1977 by
Corps' New England Division (NED) to
manage New England's regional dredged
material disposal sites. The program's main
Germane, J.D., and D.C.
Rhodes, and J.D. Lunz, 1994.
An integrated tiered approach to
monitoring and management of
dredge material disposal sites in
the New England Region,
Contribution No. 87, Report No.
SAIC-90/7575&234. SAIC,
Newport, R.I., pp-55 with
appendices.
objectives are to minimize and manage the
potential impacts of dredged material disposal
on the marine environment. DAMOS is the
most extensive dredged material disposal site
monitoring program in the world and has
conducted numerous published investigations
of dredged material behavior and effects.
Monitoring priorities are determined based
on: 1) the nature and volume of sediments
disposed at the various disposal sites; 2)
relevant findings of prior monitoring; and 3)
discussions with State and Federal resource
agencies. Typically, the most heavily used
sites are monitored on an annual basis, while
the less heavily used sites may go several
years between monitoring surveys.
Monitoring of dredged material disposal sites
has four primary objectives: 1) assuring that
disposal operations are completed, and
comply with permitted performance
standards; 2) verifying that disposal materials
and the interaction of the benthic community
behave as predicted during project design
modeling; 3) providing information that will
also optimize utilization of the disposal sites;
and 4) assuring that disposal activities are in
compliance with environmental laws and
regulations.
To address these objectives, monitoring
parameters must respond to, at a minimum,
the following questions:
• What physical and chemical
environmental effects are associated
with the proposed dredged material
disposal activities; and
• What biological responses are
associated with those physical or
chemical effects?
5-24
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Specific sampling plans must be designed
within this context, and, the pre-existing
environmental conditions of the disposal
site(s), and any sensitive receptors and/or
risk pathways associated with on-site
resources and the user populations.
5.7.2 Sampling Plan
Typical monitoring at disposal site(s) will
consist of a depth (bathymetric) and sediment
profile camera survey (e.g. REMOTS).
Monitoring of in-channel placement locations
will be conducted as part of the project
construction and will consist of depth surveys
to assure that minimum navigation depths are
not impacted. It is anticipated that the
surveys will be used to document the
placement of material at the site and to
confirm the expected recovery of the benthic
organisms after disposal ceases. Similar
surveys at MBDS, following the disposal of
material from the dredging for the Third
Harbor Tunnel, indicated the continued
development of a large disposal mound and
healthy benthic recolonization.2,3
SAIC, 1994a. Baseline Survey of
the Massachusetts Bay Disposal
Site: Final Designation, 14
September 1993. Draft DAMOS
Report, Submitted to the U.S.
Army Corps of Engineers, New
England Division, Waltham,
MA.
SAIC, 1994b. Monitoring Cruise
at the Massachusetts Bay
Disposal Site, August 1994.
Draft DAMOS Report,
Submitted to the U.S. Army
Corps of Engineers, New
England Division, Waltham,
MA.
REMOTS scanning will provide an
opportunity to evaluate the as-built conditions
of the disposal cells or mounds. Conditions
such as visual grain size and/or re-
colonization anomalies suggesting
unanticipated disposal materials response can
be easily determined. Based on visual
estimation of the photographic anomaly,
further action(s) may be determined if
necessary (e.g. chemical or bioassay
analyses).
REMOTS scanning also provides an
opportunity to indirectly evaluate biological
resource conditions using trend or surrogate
means. This approach establishes a
hierarchy of trend or surrogate measures that
provides a foundation for resource
evaluation. As an example, the enumeration
of polycheate tubes at the sediment-water
interface, is a surrogate measure for:
• Densities of opportunistic
colonizing polycheate
species, which is a surrogate
measure for:
• The rate of benthic
secondary production of
. prey species, which is a
surrogate measure for:
. • Life history impacts of
commercially important
demersal fishery species,
which is a surrogate measure
for;
• An early warning signal that
disposal impacts may affect
human health.
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Bentbic surveys conducted to evaluate the site
alterations show that conditions within the
Mystic River, Inner Confluence and the
Chelsea Creek are already of low benthic
resource value, and therefore both biological
and chemical monitoring is unwarranted. In
fee short term, the project will improve
beathic conditions. However, should areal
conditions (e.g. CSO discharges and runoff)
remain unchanged, post-construction
sediments should return to pre-project
conditions. Because a granular cap is
replacing me existing surface silt layer, a
temporary shift in the benthic assemblage
from silt-loving to sand-loving organisms and
men back again when the silt returns should
be expected. Also, mis pre^roject sediment
condition is not isolated to the channel, rather
me channel is reflective of the greater
harbor.
5.7.3
Requirements.
Results of the long term monitoring
investigations conducted under DAMOS will
be prepared in report form, reviewed, and
published as a DAMOS contribution. The
DAMOS contributions are distributed to
regional State and Federal resource and
permitting agencies for review and comment;
the interested public, and many regional
college and university libraries (such as
UMASS Boston, Woods Hole Oceanographic
Institute, etc.) as public information.
5.8 CONTINGENCY PLANS
A key element of the properly managed
dredging operation for the BHNIP will be the
identification and planning for anticipated
problems which may develop. The following
sections describe environmentally related
contingencies, which could be implemented
when such problems are encountered. It
must be recognized that these identified
contingencies do not necessarily exhaust all
possible operating scenarios. It is anticipated
mat the Contractor will be required to
develop a detailed Contingency Plan as part
of the contractually required submittals.
These contingencies would be identified in
the Accident Prevention and Site Emergency
Plan and the Environmental Protection and
Turbidity Control Plan.
5.8.1 Project Delays
Any long term marine construction project
may be subject to periodic delays resulting
from any number of causes. Reasonable
delays are typically factored into the overall
schedule for the project. A detailed Project
Schedule will be developed at the start of the
project. The Corps, Massport berth owners
and contractor will participate in me
development, review, and approval of the
schedule. The progress of the BHNIP will be
continuously monitored by the Contracting
Officer. Any prolonged delays which could
impact critical milestones, such as meeting
specific environmental milestones or permit
conditions, will activate contingency plans.
The cause of the delays will be critically
reviewed and procedures will be
implemented to eliminate those delays.
To assure that Contractor delays will not be
extended and potentially threaten completion
of the project, the Contracting Officer will
have the authority to require the
mobilization of additional equipment and
personnel as may be required. The
Contractor will be obligated to provide the
5-26
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proper equipment and labor, at his/her cost,
to perform the contracted services within the
established time schedule. Delays caused by
conditions which are not within the control of
the Contractor, such as weather related
phenomena, water quality degradation due to
a non-project related occurrences, or other
uncontrollable conditions will be treated in a
similar manner. The Contractor will be
required to mobilize additional personnel and
equipment, as may be required, but will be
compensated for providing mat contingency.
5.8.2 Operations Issues
There are many issues associated with the
effective and successful execution of the
dredging, blasting, disposal, and support
operations for the BHNIP that may trigger
contingency requirements. These are
described hi the following paragraphs.
5.8.2.1 Operator Qualifications
It is essential that the most qualified and
experienced persons be employed in critical
roles for all aspects of this project. One of
the most crucial positions is that of the
dredge operator(s). Experience has shown
mat the skills of the dredge operator will be
fully exploited to ensure that bucket dredging
is performed with minimal impact to water
quality. The operators must be keenly aware
that bucket impact on the channel bottom,
closing speed during excavation, haul speed
through the water column, surface breaching
techniques, and scow loading operations are
all potential sources of turbidity. Turbidity
must be minimized during all project
operations, but especially during the dredging
of the silt layer.
The Contracting Officer will contractually
reqilire the Contractor to employ dredge
operators with demonstrated exemplary
skills. The Contracting Officer will reserve
the right to require the Contractor to replace
any operator that does not meet minimum
skills or does not demonstrate an ability to
satisfy the performance parameters demanded
by this project.
5.8.2.2 Trash and Debris Management
It is recognized that the proposed activities
will likely encounter various types of trash
and debris on the channel bottom and in the
berth facilities. The dredge plant will be
capable of removing and managing most, if
not all, of these materials.
Several contingencies must be considered.
The Contractor will be required to contain
and collect all floating debris which result
from the dredging operation. Floating debris
and solid trash will be collected and placed
into containers which will be maintained on
the dredge or support barge. This debris will
be periodically offloaded and transported to
an appropriate landfill for proper disposal.
Dredging operations may periodically release
petroleum products which are entrapped in
the bottom sediments. During dredging these
oils may be released and consequently collect
on the water surface. The Contractor will be
required to maintain sorbent booms and
clean-up materials to immediately eliminate
any such surface impacts.
While it is unlikely that unforeseen containers
or drums containing unknown and possibly
hazardous materials will be encountered, it
will be prudent to include such occurrences
hi a contingency plan. The Contractor will be
5-27
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required to submit, as part of the Accident
Prevention and Site Emergency Plan, a
detailed procedure for handling and
managing unknown containers. At a
minimum., this contingency will include
required response notification protocol,
testing requirements, health and safety
procedures, drum handling procedures,
diving support as required, and disposal
requirements.
5.8.2.3 Disposal Operations
The critical elements of the disposal
operation include: construction of the in-
channel disposal cells; placement of the
dredged silts into the disposal cells;
containment of turbidity which may result
from me disposal operations; and installation
of the cap system. Each of these tasks will be
planned and executed with some inherent
risk. The design process is specifically
required to minimize risks. Development of
contingency plans for those elements of risk
which are difficult or impossible to quantify
will further assure the successful completion
of the project The following paragraphs
identify mree disposal operation
contingencies.
Design of the in-channel disposal facilities is
constrained by the geotechnical properties of
the parent material, the approximated
stability of contiguous structures, and the
assumed bulking properties of the silt
materials. It has been estimated by the Corps
that 1.1 million in-situ cy of silt will bulk to
approximately 1.3 million cy requiring in-
channel disposal. The available capacity of
the in-channel facilities has been estimated by
the Corps to be only slightly more than 1.3
million cy. It is clear that a modest variation
in any of the factors affecting the disposal
volume approximations could require
alternative disposal plans. Because of the
expected small quantity, upland disposal of
these materials or use in an ecological
improvement project hi the Little Mystic
River could accommodate those silts which
might not fit into the available m-channel
facilities. It should be clear, during the initial
disposal phases of the project, if the volume
allowances and bulking assumptions were
adequate.
It may be effective to restrict scow dumping
procedures to times of slack tide. Maximum
tidal velocities through Boston Harbor occur
approximately 3.5 hours after low water and
about 4 hours after high water. Slack tide
occurs at the time of high or low water.
Migration of any turbidity plume, which may
result from the dumping operation, would be
minimized by avoiding times of peak tidal
velocities.
5.5.2.4 Permit Conditions Exceeded
The BHNIP will be constructed under the
conditions of the environmental permits
dictated by the appropriate regulatory
agencies. Significant exceedance of the
allowable levels for turbidity and other
possible monitoring parameters may require
a modification of the operation which causes
the exceedance. The first requirement of the
project monitoring staff will be to quantify
the exceedance and identify the specific
source of the exceedance. If the source is not
project related, dredging, disposal, and/or
rock removal operations would continue. If
the significant exceedance is clearly caused
by the BHNIP construction operations,
remedial action alternatives will be evaluated.
5-28
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The Contracting Officer will identify the
appropriate contingency to mitigate the
exceedance. The Contractor will be required
to immediately implement the required
contingency.
Li the event that no appropriate contingency
plan is available, the Contracting Officer
shall develop a specific procedure. If
appropriate, that procedure will be reviewed
with appropriate regulatory agencies and
implemented with their approval. These
agencies must recognize mat an immediate
response to such field modifications will be
essential. Each agency should identify a
responsible contact person, who will be
available at all hours with authority to
approve procedural changes.
5.8.2.5 Equipment Failure
Contractor equipment failure will not be
allowed to impact the project schedule or
affect the water quality conditions imposed as
a part of the project contract. The Contractor
will be required to immediately repair any
failed equipment or to replace critical
equipment to the satisfaction of the
Contracting Officer.
5.8.3 Environmental Conditions
Any marine related construction activity is
subject to the inclement weather. Responsible
Contractors are experienced hi dealing with
weather related impacts. Project specific
concerns include the possible effects of
dredging related noise and odors on the areas
in the immediate vicinity.
5.8.3.1 Weather Related Issues
Normal weather phenomenon do not
typically impact dredging operations. Blasting
activities may be sensitive to precipitation.
However, extreme weather can significantly
impact the proposed activities. The Boston
area is subject to periodic severe northeast
storms and to seasonal hurricanes. Extreme
water surface fluctuations, high winds, and
intense precipitation are characteristics of
such events. The duration of these events
rarely exceeds several days, with the most
intense activities lasting a matter of hours.
Modern forecasting techniques will typically
provide adequate time to secure the
construction equipment and to implement
procedures for the protection of life and
property. The approved Accident Prevention
and Site Emergency Plan will identify
specific procedures for evacuating personnel
and for safely securing floating equipment hi
the event of such severe weather.
Stability of the dredging, disposal, and
blasting work in-progress will be a great
concern during extreme weather events.
Blasting operations would be terminated as
far in advance of the predicted event as
possible. All explosive materials will be
removed from the site and stored at secure
upland facilities which are likely to be at
Massport owned waterfront industrial site
depending on the blasting location. As part of
the normal daily procedures, the disposal and
capping operations must be carefully
coordinated. Capping of the placed silts must
be done as soon after placement as possible.
Severe storm activity could potentially
generate waves which could resuspend
uncapped silts. Resuspended silts could
migrate to areas outside of the disposal cells.
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Interim hydrographic surveys of the work
sites should be performed if possible. These
surveys would indicate the position of the
placed silts, capping material, and extent of
completed dredging before any storm effects.
Post-storm surveys would be performed in
the same areas to evaluate the effects on the
work sites. These surveys would provide
vital information to the Contracting Officer
and allow for the proper planning of repairs
to any damaged sections of the cap and
identify areas which might require re-
dredging.
Precautions to prevent "short dumping" of
dean parent material prior to arrival at the
MBDS include: monitoring of weather and
sea conditions, prohibiting the scow from
leaving the harbor, establishing a point of no
return and employing dredge inspectors to
verify the disposal location.
5.8.3.2 Noise
The proposed areas to be dredged are all
located within the Designated Port Areas of
Boston Harbor. Periodic dredging is a
necessary and normal activity within these
areas. Noise associated with dredging is
characterized by sources common to Port
activities and is expected to be minimal.
Limited reaches of the proposed project are
situated in the vicinity of commercial and
residential structures. Typically, the dredge
will not operate in one position for any
extended time. Dredging is a progressive
operation and will expose
any specific location to the associated noise
for only a matter of weeks. It is anticipated
that the dredge will operate continuously (24
hours/day 7 days/week).
5.8.3.3 Odor and Air Quality
Dredged materials will normally contain
traces of organic matter and can generate
distinct odors when removed from the
channel bottom and placed in scows. Such
odors are typically associated with the release
of hydrogen sulfide and methane. Dredging
of typical channel sediments will not
normally release these gases at concentrations
that could be harmful.
The odor associated with even low
concentration releases of hydrogen sulfide
and methane can be obnoxious. Scows will
typically have a thin layer of water which
covers the majority of the load. This cover
will tend to minimize gas release. Released
gas will be readily dispersed hi the
atmosphere. While odor can be of concern, it
is not typical for odor issues to persist at
projects, such as the BHNDP, where the
material is being placed in submarine
facilities. Odor problems are most often
associated in the vicinity of permanent upland
storage facilities. This will not be typical of
the BHNIP operations.
5-30
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Figure 5-1. Cu and Zn Concentrations 11 Yrs. After Placement: Interface at 80 to 100 cm
1000
900
y«.ys <...!..{..#..'....%.:.?.
100
0-20
20-40
40-60
60-80 80-100
Depth in CM
100-120
120-140
140-160
-------
u
Figure 5-2. PAH Concentrations 11 Years After Placement: Interface
at 80 to 100 Cm
CL
Q.
90
80
70
60
50
40
30
20
10
0-20
20-
40
40-
60
60-
80
80-
100
100-
120
120-
140
140-
160
Depth in CM
1 Phenanthrene
H Anthracene
H Fluoranthene
il Pyrene
-------
Figure 5-3
c - Chelsea Cr cell. Boston Harbor Navigation Improvement Project
M - Mystic River ceii Schematic Dredging and Disposal Sequence
1C - Inner Confluence cell In-Channel Disposal
siit
Parent
Dredge 1
Dredge 2
o
o>
o.
<
Chelsea Store
for
C12
Cell used
C12
C11
ci2-^- Cell created
C11
o>
o
o>
o>
13
0>
CD
C10
C10
C9
-C9-
C8
C9
C8
C7
C7
_ C6
C7
C6 Mov|||o Mystic
•M25
M25
M24
M24
M23
M23
M23
M20
Start in Chelsea Cr.
C11
C10
i
C10I
C9
C8
I
Move to Inner Confl.
csm
IC2
IC2
IC2I
IC2I
IC2
ICS
IC3
IC3a
IC4
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Chapter Six: Summary of Project Impacts and
Mitigation Opportunities
This chapter of the FEIR/S summarizes the
primary, secondary and cumulative impacts
imposed by the Boston Harbor Navigation
Improvement Project (BHNIP) and
identities potential mitigation opportunities
which would offset these impacts.
Primary impacts are those that include
physical disruption or displacement
(temporary or permanent) caused directly
by the proposed dredging or material
disposal activities. Primary impacts also
include such issues as turbidity/suspended
solids, sedimentation, dissolved oxygen
(DO) reduction, chemical release, noise
and odor.
Secondary impacts include indirect effects
such as land-based changes, increases in
truck traffic and changes in vessel traffic,
if any. Cumulative impacts include all long
term effects of the BHNIP, in association
with future maintenance dredging, and
reasonably foreseeable long-range material
disposal issues.
This chapter also identifies potential
mitigation opportunities for these impacts
within the framework of federal and state
regulations. Section 6.1 summarizes and
quantifies the primary, secondary and
cumulative impacts caused by the preferred
alternative identified in Section 4.0 of this
FEIR/S.
6.1 PRIMARY IMPACTS OF
PREFERRED PROJECT
6.1.1 Direct Impacts to Resource Areas
The primary impacts associated with
dredging include direct disturbance of
bottom sediments in the areas to be
dredged. The preferred project
alternative, termed the Full Project (see
Chapter Two), will remove contaminated
silt on 320 acres within the Boston Inner
Harbor representing approximately 21% of
the Inner Harbor area. This acreage is
made up of the following individual areas:
Federal Project
• Reserved Channel: 44 ac.
• Main Ship Channel: 18 ac.
• Mystic River/Inner Confluence: 134 ac.
• Chelsea Creek: 68 ac.
Project Beneficiaries
• Prolerized/Distrigas Terminals: 6 ac.
• Moran Terminal: 1.5 ac.
• Eastern Minerals Terminal: 1 ac.
• Gulf Oil Terminal: 7 ac .
• Conley Terminal: 14 ac.
6-1
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Non-Beneficiarv Berths
• Revere Sugar Terminal: 1.5 ac.
• Mystic Piers Terminal: 3 ac.
• North Jetty Terminal: 3.5 ac.
• Army Base: 13 ac.
• Boston Edison Intake: 0.5 ac.
• Boston Edison Barge Berth: 0.5 ac.
Approximate total acreage of full
project: 315.5 acres, rounded to 320
acres in this report.
The Full Project will remove about 1.1
million cy of silt, 1.7 million cy of parent
material, and 88,000 cy of rock, all
measured in place. Due to expansion
during removal and handling, the
corresponding bulked volumes required for
disposal are approximately 1.4 million cy
of silt, 2 million cy of parent material, and
132,000 cy of rock.
Based on chemical analyses and results
presented in the DEIS/R, the parent
material and rock is considered suitable for
a variety of unconfined disposal options.
As described hi Chapter Three, several
beneficial uses of this material are planned
or under consideration. These include:
Parent Material
Open Water Containment Cap
Nearshore Containment Cap
Subbtidal/Intertidal Habitat
Creation
Landfill Liner/Cap Closure Material
Rock
Fish Habitat Enhancement
Shoreline Protection
Containment Site Development
Upland Fill/Commercial Reuse
Armoring for Disposal Site
The disposal of the silt materials is a more
complex issue. Based on the sediment
analyses and results presented in the
DEIR/S, the 1.4 million cy of silt
generated by the Full Project is considered
unsuitable for unconfined ocean disposal
sites.
Chapter Four of the FEIR/S detailed the
selection process for the preferred material
disposal alternatives. In-channel disposal
has been determined to be the LEDPA,
and will handle the entire 1.4 million cy of
material removed from within the dredging
footprint based on design calculations
performed by the Corps. The in-channel
cells will occupy 116 acres.
While it is expected that in-channel
disposal would provide sufficient capacity
for all contaminated silts, excess capacity
for contingency planning purposes, has
been identified and evaluated as part of the
FEIR/S in response to agency comments.
As described in Chapter Four, Little
Mystic Channel (LMC) could provide an
additional 15 acres or 303,000 cy of
confined capacity within the Mystic River
Designated Port Area (DPA). This site
also ranked fairly low in terms of severity
of environmental impacts along with the
other shoreline sites (see Table 4-6). It
also rated, in general, moderately
practicable in the practicability screening
and was one of the least costly options (see
Table 4-7).
In summary, the primary impact of the full
project dredging and the in-channel
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materials disposal would include the
temporary displacement of benthic
substrate over approximately 320 acres in
a DPA. Should the LMC be required as a
contingency site, it would impact an
additional 15 acres of benthic habitat in a
DPA.
As part of project planning, the project
team conducted a functions and values
assessment. As presented in Appendix K,
this assessment has been presented as a
"Principal Valuable Function Evaluation"
(PVF). The purpose of the PVF is to
provide a process to compare real pre-
project functional conditions against effects
caused by the BHNIP. Based on this
comparison, conceptual mitigation
considerations (if necessary) can be
developed to offset anticipated impacts.
The PVF describes significant resource
conditions during the pre-project phase and
the dredging and disposal phases. The
resulting substrates over the in-channel
disposal areas will consist of clean
granular material as opposed to the present
condition of contaminated silts. Given the
current trend of improvement in Boston
Harbor water quality, the disposal and
sequestering of contaminated silts should
help to provide cumulative benefits to the
BHNIP project area.
6.1.2 Dredging Impacts
6.1.2.1 Water Quality/Sediment Quality
A mechanical bucket dredge will be used
to excavate the substrate. Only a relatively
small percentage of the dredged material
becomes suspended in the water column
when the appropriate equipment (i.e., an
environmental bucket for the silts) is used.
More of the material would be released
during dredging operations if large debris
prevents the dredge bucket from closing.
To minimize this, the environmental
bucket will be fitted with a sensor to alert
the operator if the bucket fails to close.
Suspended material resulting from the
dredging project is principally restricted to
the silt or clay fraction (<.06 mm) with
sand particles (> .06mm) settling out
immediately after suspension. Grain size
analyses of 18 stations in Channels identify
the substrate as 86.5% clays and silt,
11.2% as sand, and 2.3% rock.
The organic material associated with the
silt and clay materials could depress
ambient oxygen concentrations. However,
the chemical oxygen demand for all 18
stations sampled averaged 80,509 ppm for
surficial samples, a moderate value. The
clean parent material (approximately 62%
of the material to be dredged) would not
exert an oxygen demand on the water
column because this material does not
contain substantial organic materials.
Increased turbidity would reduce light
penetration, lessening primary productivity
and possibly reducing oxygen release from
photosynthetic processes. Finally, upon
settling, the suspended sediment load, both
sand and silt/clay, could cover non-motile
organisms adjacent to the dredging areas.
All of these effects are expected to be
spatially and temporally limited to the
immediate area of the dredge and length of
the activity. The benthic community in the
Inner Harbor is dominated by
opportunistic/pioneer species indicative of
a disturbed environment. Shellfish species
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known to exist in the tributaries are not
commercially harvested.
Monitoring results (EA, 1992) of dredging
activities for the Central Artery/Third
Harbor Tunnel Project (CA/T) indicated
that Boston Harbor main ship channel
dredge plume, generated during the tunnel
trenching, was diffused and dispersed
within 500 feet. Background (up-current)
total suspended solids ranged from 8-20
mg/1 and the plume (500-ft. down current)
ranged from 8-34 mg/1. BHNIP would
expect similar results. Additional
modeling results are presented in Appendix
F (ASA 1995). These results estimate that
during dredging operations a small portion
("2%) of the dredged material is released
into the water column (Tovalaro, 1984
cited in ENSR, 1991). This fraction
accounts for both material suspended by
the dredge (1.2%) and dredge scow
overflow (0.8%). It is assumed that
release from dredging operations will be
continuous.
All of the effects associated with increased
turbidity in Boston Harbor would occur in
the immediate area of the dredge, be
transported by currents, and settle rapidly.
After completion of the dredging activity,
these impacts will cease. The motile
organisms should generally escape this
downcurrent sedimentation by leaving or
avoiding the area of activity. Sessile
organisms will be impacted. However,
sessile organisms inhabiting Boston Harbor
are estuarine species that are tolerant of
recurring turbidity stresses.
One of the functional characteristics of an
estuarine system, such as Boston Harbor,
is to serve as a nutrient retention area,
increasing the productivity of its
subcomponents. Nutrients are effectively
"trapped" in the sediments where they are
stored. This trapping and storage function
also allows for the retention of pollutants
in the same substrates, especially in fine
grained sediment which have a larger
surface area for pollutant adsorption. The
physical removal of these sediments by
dredging operations has the potential to
release some of the sediment bound
pollutants.
A review of the levels of sediment
chemistry, the ambient water quality and
the use of an environmental bucket or
clamshell dredge, indicates that a low
potential exists for substantial degradation
of ambient water quality during dredging.
After project completion, the benthic
substrate of the Boston Harbor will be less
contaminated in the dredged areas due to
the removal of the surficial sediments
which contain a majority of the
contaminant load and placement of clean
cover material, thus providing a beneficial
effect.
6.1.2.2 Biological Resources
The primary impact of this project on
biological resources will be the removal of
benthic organisms inhabiting areas to be
dredged. This impact could represent a
low (29 organisms/m2) to high (4,800
organisms/m2) loss of benthic organisms,
depending on the season and areas to be
dredged. As described in Section 4.0,
NAI conducted a fisheries, lobster and
benthic survey within areas of the Harbor
potentially affected by dredging and
disposal activities. REMOTS data for the
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in-channel Mystic and Chelsea River
resulted in an organism sediment index of
3.0, indicating moderate habitat value.
The dredging of the channel will cause a
short term loss of benthic productivity that
will be rapidly offset through faunal
recolonization. This recolonization
potential has been recently demonstrated
by MWRA studies of Harbor areas
disturbed by the 1992-93 winter storms.
These areas were extensively recolonized
by opportunistic species such as Ampelisca
sp. (J. Kelly, pers. comm. 1993).
Fishery resources associated with the
Mystic River, Chelsea Creek and Inner
Confluence should be considered
moderately significant. Representative
lobster catch data for the three reaches
within the dredging footprint is calculated
as Catch Per Unit Effort (CPUE) as
follows:
Mystic River: 0.2
Chelsea River: 0.2
Inner Confluence: 0.9
Mystic River and Inner Confluence catch
data are dominated by sublegal sized (<
83mm) males, whereas Chelsea River data
is equally distributed by size
Oegal/sublegal) and sex.
Representative BHNIP finfish data, based
on 20-minute trawls, in the same study
areas, is also calculated as CPUE as
follows:
Mystic River: 21.8
Chelsea River: 25.0
Inner Confluence: 13.59
The Mystic River catch was dominated by
winter flounder, atlantic tomcod and scup.
The Chelsea River catch was also
dominated by winter flounder and atlantic
tomcod. At the Inner Confluence, the
dominant species was winter flounder.
These findings are comparable with
previous finfish surveys in the area (e.g.
Haedrich and Haedrich 1974).
Chemical signals essential for anadromous
fishery migrations could become masked
by the dredging operation's suspension of
sediments and associated chemicals.
Dredging will be scheduled to avoid
impacting critical spawning runs of those
species.
Sediment suspension will also displace
motile species that will attempt to avoid
gill abrasion, lower DO levels, and
reduced sensory opportunities for predation
(masked odors and low visibility) hi the
dredging area. These would be all
temporary and the effects would not have
long term detrimental impacts.
Mortalities of fish and invertebrates are
most likely to occur during the explosive
fracturing and mechanical removal of
approximately 88,000 cubic yards of
bedrock. Fish kill zones depend on rock
density, anticipated explosive size during a
single blast, open water fish kill research,
and physical characteristics of the Harbor.
BHNIP fish density data (two seasons of
fish trawls and gill net collections) indicate
the average density in Boston Harbor is
approximately 10 fish/m2. If at any given
time the fish were present in the water
column directly over the blast and
orientated sideways to it, the maximum
moralities may range from 300 to 14,000
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fish per blasting operation. High end
mortalities would be unusual. Monitoring
of blasting operations during the
navigational improvement project in
Portsmouth Harbor in New Hampshire did
not indicate fish kills close to these
maximum ranges. However, the
monitoring results recorded only the fish
seen floating at the surface. Even if the
number of fish killed per blast are high,
they are similar to the range of fish killed
in a commercial fish trawl.
Species of marine mammals which may
occur in tidal waters in the vicinity of the
project area, include harbor seals (Phoca
vitidina), harbor porpoises (Phocena
phocena), and grampuses (Grampus
griseus). However, their presence in the
Boston Harbor system is uncommon
(Cortell, 1990). Since most of the
dredging impacts will occur well within
the Inner Harbor where marine mammals
are uncommon, the project is not likely to
cause adverse impacts to these species.
6.1.2.3 Threatened and Endangered
Species
The intertidal and subtidal areas, including
and adjacent to the Federal channel, are
not known to provide habitat for any
Federal threatened and/or endangered
species, or State rare species.
Coordination with the U.S. Fish and
Wildlife Service, the National Marine
Fisheries Service and the State Natural
Heritage Program have confirmed the lack
of any threatened, endangered, or rare
species in the dredging area.
6.1.2.4 Historical.and Archeological
Resources
Boston Harbor has been subject to
navigation improvement projects since the
mid-nineteenth century. The channels and
rivers in and around the Harbor have been
deepened, widened, and straightened. This
activity has severely limited the historic
and archeological potential of the Harbor.
The dredging portion of BHNIP will not
adversely affect sites of historic,
architectural or archeological significance,
as defined by the National Historic
Preservation Act of 1966. The
Massachusetts Historical Commission
reviewed the deep-draft navigation
improvement project, including the
berthing areas, and determined that
dredging the previously maintained
channels and berthing areas will not have
an adverse impact on any historical or
archeological resources.
The Chelsea Street Bridge is considered to
be eligible for the National Register of
Historic Places, as it is the only Strauss
heel-trunnion bascule bridge known to
survive in the Commonwealth. Navigation
improvement dredging is not expected to
impact this bridge.
6.1.2.5 Noise and Odor
Dredging with a mechanical bucket will
produce noise from the engines lifting and
lowering the dredge bucket. The noise
produced will be similar to other diesel
engine equipment in the area. Many of the
receptors in the three tributaries are
businesses. Residential areas only exist
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near the mouth of Chelsea Creek and near
the Tobin Bridge. Noise may be greater
during the warmer time of year when
people are outside more frequently and
windows are open. Although the dredges
are expected to work 24 hours a day, the
noise level will be masked by background
noise from nearby transportation activity.
Noise generated by this project should not
be substantially different from other
Harbor baseline noise levels.
In addition to the noise produced during
the dredging operation, odor from dredged
material placed on barges may occur. The
odor impact, if any, would depend on the
time of year and the direction of the wind.
The number of barges that would be filled
range from two to four per day based on
the current dredging schedule (see Figure
5-3). Therefore the potential impact would
be continuous while dredging the silt.
Perception of odor would be minimal
during the cold months of the year. This
is due to the fact that more human activity
would occur indoors and cold temperatures
could keep the odor-causing bacteria count
low. Generally, the dredging activity will
be far enough away from population
concentrations that mixing with ambient air
is expected to be sufficient to dilute
increased odors.
6.1.3 Disposal Impacts
6.1.3.1 Water Quality/Sediment Quality
Water quality modeling results (Appendix
F) conclude that under continuous loading
for the in-channel disposal option no
constituents were found to exceed chronic
water quality criteria, if material were
released up to 6,000 cy/day. Instantaneous
releases did not indicate any exceedence of
chronic water quality criteria. It is
important to note that chronic water
quality criteria are the most stringent (very
low levels) measure and much more
stringent than the legally applicable state
water quality standards.
6.1.3.2 Biological Resources
Downdrift harbor fauna should be tolerant
to stresses associated with fluctuating
turbidity levels and DO reduction. Given
Boston Harbor hydrography, the mixing
zone extends (based on TSS) over the
following areas for each of the in-channel
disposal sites:
Mystic River: 12.4 ac.
Chelsea Creek: 30.0 ac.
Inner Confluence: 14.7 ac.
Most of the episodic effects on biological
resources will be triggered by the dredging
itself. By locating the material disposal
locations within the footprint of dredging
limits the stresses associated with disposal.
6.1.3.3 Threatened and Endangered
Species
There are no impacts anticipated, since the
Federal channel and berthing areas are not
known to provide habitat for any Federal
threatened and/or endangered species, or
any State rare species.
6-7
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6.1.3.4 Historical and Archeological
Resources
Historical and archeological resources are
not anticipated to be impacted based on
coordination with the Massachusetts
Historical Commission and the Board of
Underwater Archeology.
6.1.3.5 Noise and Odors
Impacts regarding noise and odors would
be similar to, and part of, the actual
dredging operation. Therefore noise and
odors generated by the proposed material
disposal operations, should not be
perceivable beyond the actual dredging
operations or the ambient air conditions.
Noise and odor impacts may become more
of an issue if excess capacity is needed in
the LMC. Disposal and site grading at the
LMC would be near to a housing
development. Odors may be more
noticeable, not only because of the
proximity to sensitive receptors, but
because the site will be graded to intertidal
habitat, exposing the muds at low tide.
Odor controls, whether chemically applied
treatments or operational controls such as
observing wind direction in the disposal
area, would be employed should the LMC
site be needed. However, as stated earlier,
the in-channel option is expected to
provide sufficient capacity for the BHNIP
silts.
6.2 SECONDARY IMPACTS
Secondary impacts consist of those
affecting land-side issues, Harbor traffic
and other socio-economic effects. The
following subsections consider the
identifiable secondary impacts of the
preferred alternative.
6.2.1. Vessel Traffic
The BHNIP will not dramatically change
operations in the Port of Boston. Vessel
traffic is not expected to increase in
number significantly. The current mix of
vessel traffic will continue to include large
container ships, barges and tankers. Some
commentors expressed concern that the
BHNIP will attract more ships thereby
creating secondary impacts to marine
mammals, ranging from disturbing normal
behavior patterns to mortality from ship
collisions. There are in place, Coast
Guard regulations that are designed to
deter interference with marine mammals in
U.S. waters. The BHNIP is not designed
to attract a vast array of new and larger
ships. The Port geometries, and service
infrastructure, limit the eventual growth of
the Port. Therefore, vessel traffic
attributable to the BHNIP is not likely to
have secondary impacts on navigation
interests or marine mammals.
6.2.2 Terminal Improvements
The BHNIP will not dramatically change
operations in the Port of Boston. Vessel
traffic will continue to include a mix of
large container ships, barges and tankers.
The volume of cargo will not change
noticeably as a result of dredging, since
cargo volume depends on more than
channel depth. Massport continues to
upgrade its container handling facilities to
6-8
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provide "state of the art" off-loading and
storage at Moran and Conley Terminals.
Therefore dredging need not trigger
additional landside improvements at these
terminals.
6.2.3 Roadway Improvements
Inland transportation improvements to
serve the Port of Boston have long been
the subject of planning and investment.
The Seaport Access system, which is part
of the Central Artery/Tunnel Project will
result in more direct and convenient
connections for trucks between port
terminals and the regional highway
network. At the same time, through State
and Massport effort, infrastructure changes
to accommodate double-stacked trains are
being promoted. This latter effort is
separate from the dredging project. The
BHNIP will not alter these efforts in any
way.
6.2.4 Growth of Fort Devens
One of the comments on the DEIR
concerned impacts of the BHNIP on Fort
Devens and the surrounding area. The
concern related to environmental impacts
of increased activity at Fort Devens
because of additional cargo volumes being
handled at the "inland port". As stated
heretofore, the BHNIP, alone, will not
increase cargo volumes coming through
the Port of Boston. Further, Fort Devens
will not change significantly as an "inland
port" without major investment in the
railroad infrastructure serving the port.
Any project to improve rail infrastructure
would be separate and distinct from the
BHNIP. In 1994, 3% of containers
handled in the Port of Boston were moved
by rail. Of those containers, less than one
third moved by rail between Moran
Terminal and Ayer (Fort Devens) or
beyond, with the rest going through the
"inland port" facility at Fort Devens
represented only 1 % of the total container
trade in the port of Boston. It is unlikely
that this situation will change with the
BHNIP. The rail route via Ayer is
convenient for export cargo from New
England and Canada, which represents
only a small portion of the total cargo
handled by the Port.
The region's imports substantially exceed
the export cargo reflecting the nature of
industry in the area. The New England
textile and shoe industries, which
traditionally exported high volume cargo
through the Port, have given way to
industries producing low volume, high
value cargo which is generally shipped by
air. The current export/import balance is
expected to continue in the future
regardless of the impact of dredging.
Growth at Fort Devens will not be
materially affected by import cargoes being
carried by rail from Moran Terminal.
6.3 CUMULATIVE IMPACTS
Cumulative impacts include all long term
maintenance requirements of the BHNIP in
association with reasonably foreseeable
long-ranged material disposal issues.
These impacts also consider other actions
in the Boston Harbor area that may have
6-9
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an impact on, or be impacted by, the
project.
6.3.1 Maintenance Dredging
Currently, estimates indicate that BHNIP
will need to dredge and dispose of 4.4
million cy of material in the 50-year
project life scenario to maintain the ship
channel.
The selection of the disposal site for future
maintenance dredging must reexamine the
environmental and practicability criteria
discussed in Chapter Four. Factors such
as sediment characteristics and volume of
the dredging project will be critical in
determining the suitability of the disposal
sites. Sites that were identified in this
review as having lengthy permitting needs,
but were otherwise reasonable, would also
be reviewed carefully. The disposal site
for future maintenance will be determined
based on the appropriate environmental
regulations and technical evaluations at that
time. The New England Division Corps
recommends, and will participate with the
Commonwealth, in conducting an overall
regional dredged material management
plan for future maintenance of all
Massachusetts Bay's harbors.
6.3.2 Relationship to Other Projects
During construction of this project,
additional barge traffic will occur in the
shipping channels and at the open water
disposal sites. Barge traffic from the
BHNIP is not anticipated to interfere with
barge traffic from the Central Artery/Third
Harbor Tunnel (CA/T) project. Barge
traffic to Spectacle Island is anticipated to
be complete by the end of 1998. Barge
traffic for the CA/T project will leave
from Subaru Pier, north of Reserved
Channel, during the summertime, May
thru September. Additional small barge
traffic will begin next summer in 1996 to
transport material from the Fort Point
crossing area. BHNIP activities will not
be coincident with this work.
The MBDS is not receiving any more
material from the CA/T project.
Approximately 470,000 cubic yards of
material from the CA/T project was
disposed at the MBDS. No material was
disposed at this disposal site from the
Massachusetts Water Resources Authority
(MWRA) project in Boston Harbor (the
other large project in Boston Harbor).
Other small dredging projects in the
Massachusetts Bay area may dispose of
materials at the MBDS. The draft and
final EISs for the MBDS site designation
discuss the cumulative impacts from
disposal at the MBDS. However, because
of the current designation restrictions to
the MBDS, the likelihood of many projects
being accepted for disposal there is slight.
Disposal of clean parent material at the
MBDS is not expected to interfere with the
monitoring efforts of the outfall pipe for
the MWRA project. About 95 to 97% of
the parent material will be deposited within
the MBDS. Any suspended material that
may leave the disposal site will be mixed
and diluted with other suspended solids in
Massachusetts Bay.
Beneficial cumulative impacts are expected
with the dredging of silt material from the
navigation improvement project. Silt
6-10
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material will be removed from the
navigation channel and disposed in-ehannel
and capped with coarse grained material
which will sequester the contaminants.
This will isolate the silt material, leave
clean material in place, and will
substantially increase the volume of clean
substrate in the Inner Harbor. At the same
time, the MWRA is controlling sludge and
CSO's disposal into the harbor, and will
have a new sewage treatment plant in
operation. This will reduce the amount of
contaminants released to the Harbor. The
clean substrate in the Inner-Harbor and the
reduced level of contaminants entering
Boston Harbor will have an overall
cumulative benefit.
6.3.3 Irreversible and Irretrievable
Commitment of Resources
Construction of this project will result in
the use of diesel engines on dredges used
to remove material from the navigation
channels and berthing areas, and to dispose
of the material. Diesel fuel, which is an
irreversible and irretrievable resource, will
be used to operate this equipment. A
minor temporary increase in air pollutants
will occur as a result of this action.
In-channel disposal of silt material will
eliminate the use of this area for future
disposal of maintenance material. The
contractor will be directed to dig as deeply
as possible in the navigation channel to
increase storage capacity. This will
maximize the use of in-channel disposal
and the use of parent material for
beneficial use.
Disposal of clean parent material will
reduce the capacity of MBDS by an
incremental amount. The capacity of
MBDS will be reduced by approximately
two million cy (or less, if used
beneficially). Although this is a large
amount of dredged material, the MBDS
will still have many more years of useful
capacity.
6.4 MITIGATION FOR DREDGING
AND DISPOSAL IMPACTS
Based on the preceding summary, several
options for mitigating unavoidable impacts
are described in this section. Critical to
the understanding of mitigation planning is
the regulatory framework that provides the
underpinning for developing mitigation
plans that not only address a specific
impact but create long-term value to the
impacted areas. This regulatory
framework consists of local, state and
federal interests.
An overriding principle is establishing
mitigation concepts is the Council on
Environmental Quality (CEQ) protocol for
establishing and prioritizing mitigation
measures incorporated into the Clean
Water Act, Section 404 (b)(l) Guidelines,
and the EPA/Corps Memorandum of
Agreement on their implementation. The
overall principals are:
• The avoiding of an impact altogether by
not taking a certain action or part of an
action;
• The minimizing of impacts by limiting
the degree or magnitude of the action
and its implementation;
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• The rectifying of the impact by
repairing, rehabilitating, or restoring
the affected environment;
• The reducing or eliminating of the
impact over time by preservation and
maintenance operations during the life
of the action; and
• The compensating for the impact by
replacing or providing substitute
resources or environments.
The following sections describe how the
BHNDP complies with this hierarchy from
project design through post-construction
monitoring.
In addition to complying with specific
conditions or policies as required by
regulatory agencies, the BHNIP has
incorporated design and operational
mitigation actions to offset any adverse
effects generated by the project. These
include:
1. Capping with sand, with rock armoring
in high-scour areas
2. Scheduling of dredging and disposal to
fit environmental windows and to meet
water criteria
3. Coordination with the U.S. Coast
Guard to avoid interference between
BHNIP activities and commercial traffic
4. Scheduling to avoid peak recreational
Harbor usage (4th of July, other holidays)
5. Identification of significant structural
features (bridge abutments, utility lines,
bulkheads, moorings, buoys, etc.)
6. Dredging performance standards to
meet environmental and permitting
conditions as well as design controls
i
7. Use of environmental bucket to trap
contaminated sediments during dredging
and outfitting it with a sensor to detect
closure problems due to debris
8. Use of silt curtains during disposal
9. Employment of fish deterrence systems
during blasting
10. Requirement for contractor to provide
an incident response plan to cover spills of
dredged material, fuel, and machinery oil
11. Trash and debris management on
separate scows with agreements to dispose
of material in landfills
12. Contingency plans for reasonably
foreseeable equipment failures, weather
conditions, encounters with buried
structures, and permit limit exceedences
The following paragraphs focus on
resource mitigation requirements in terms
of the CEQ mitigation protocol.
6.4.1 Avoidance
As described in Chapter Two, the Full
Project alternative is the preferred project
alternative to be implemented. The
dredging footprint is unavoidable, but as
described earlier, any disruption or
displacement of benthic organisms is
temporary.
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As described in Chapter Four, the BHNIP
proposes to dispose of the bulked volume
of 1.4 million cy of contaminated silt using
two LEDPA strategies. The first will
dispose and sequester the silts in place by
overdredging 54 cells into the underlying
clean parent material. These cells will be
located within the existing dredge
footprint, avoiding additional spatial
requirements.
Second, the clean parent material (clay)
and rock, not expended hi beneficial uses
(e.g. landfill liner or capping material),
will be disposed at a previously approved
and permitted disposal area (MBDS). No
BHNIP silt or parent material disposal will
be conducted hi significant offshore marine
fisheries resources such as the Meisburger
sites.
6.4.2 Minimization
When avoidance is not feasible, the
BHNIP will be designed to minimize
adverse effects to sensitive resources and
interests. Minimization includes limiting
the spatial extent of the proposed dredging
footprint to meet the size and draft of the
largest vessels transiting the proposed
channel, thereby minimizing the volume of
the dredge material required for disposal.
Limiting project activities to areas within
DPA's, minimizes impacts to areas
designated to support water dependent
industrial and maritime uses. Other
elements minimizing impacts include the
design and operational measures
summarized above under Section 6.4.
6.4.3 Rectification
The BHNIP will be prepared to rectify any
unexpected impacts, or impacts caused by
temporary project elements (e.g. staging
areas, piers, piles, etc.) after they have
been used and removed from service.
These activities are more fully described in
the mobilization and demobilization
sections of Chapter Five.
6.4.4 Reduction or Elimination
The use of in-channel cells to dispose and
sequester contaminated materials reduces
or eliminates future adverse effects of this
material's continued exposure to aquatic
resources and keeps the material close to
its source and therefore does not "export"
contamination to more pristine areas. This
is also the case should use of LMC be
required for contingency capacity.
However, this contingency option would
require compensation for lost benthic
habitat.
6.4.5 Compensation
The mitigation protocol hierarchy places
compensation for resource impacts as the
lowest prioritized option. This means that
avoidance, minimization, rectification or
reduction of impacts should be exhausted
first.
To establish compensation as a permittable
mitigation option, the BHNIP must prove
that the preceding mitigation alternatives
(avoidance, minimization, rectification and
reduction/elimination) are not completely
practical or feasible to address all project
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impacts. Once established as a suitable
mitigation option, compensation must be
based on offsetting any adverse effects to
protectable resources.
In an attempt to define the requirements
for resource mitigation, the project team
conducted a preliminary identification of
potential sites and projects for mitigation
consideration. Based on the PVF
(Appendix K), the BHNIP should not be
required to provide compensatory
mitigation. These findings are summarized
below:
6.4.5.1 Summary of PVF Conditions at
the In-Channel Sites
Benthic Habitat: Pre-project conditions
include an opportunistic and pioneer
community of low abundance, over the
entire 116 acres that will contain the 54
disposal cells. The disposal footprint is
less than the 320 acres of dredging impact
primarily since the Reserved Channel and
its entrance from the Main Ship Channel,
would not contain disposal cells. The
project will establish 152± acres of clean
granular material substrate and 50 ± acres
of clean hard rock substrate. These
project conditions will provide a more
varied habitat (soft and hard substrates),
and should support a more abundant and
varied community (burrowing and
epibenthic).
Shellfish/Lobster Habitat: Pre-project
conditions include the area being mapped
by EOEA (1978) as shellfish habitat, and
yielded moderate CPUE catch data for
lobster at 1.4 per trap day. The project
will establish 152± acres of clean granular
material substrate and 50 ± acres of clean
hard rock substrate. Project effects should
not alter EOEA's mapping of the shellfish
resource. These conditions should enhance
existing shellfish habitat, and attract hard
substrate species (e.g. blue mussels); and
improve existing feeding, resting, refuge
and breeding habitat for lobster.
Fmfish Habitat: Pre-project conditions
indicate a low abundance of demersal and
pelagic species typically found in the
Boston Harbor area. An anadromous fish
run exists through the Inner Confluence
and Lower Mystic River portion of the in-
channel area. Project activities may pose
short-termed disruptions to existing finfish
activities, but these should be limited in
terms of time and location of activity and
can be avoided by observing the
environmental "window". The clean
granular substrates should enhance finfish
habitat following completion of the project.
Production Export: Production export
does not exist in either the Pre-project
evaluation scenarios. Parts of the 50+
acres of rock cap may provide attachment
for species, and any attached aquatic
vegetation should provide some additional,
but limited production export function, in
the post project condition.
Sediment/Shoreline Stabilization:
Sediment/Shoreline Stabilization occurs,
and will continue to occur, in each of the
evaluation scenarios. Areal bulkheads and
wharves will not be adversely impacted by
the project. Removal of contaminated silt
and replacing the surficial layer with clean
sand will also enhance this function.
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Wildlife Habitat: Currently feeding
habitat for waterfowl, dabbling and diving
birds, and some roosting sites exist.
Project activities may pose short-termed
disruptions to existing wildlife activities,
but these should be limited in terms of
time and location. No enhancement of
habitat conditions is anticipated.
6.4.5.2 Summary ofPVF Conditions at
LMC
As stated earlier, the project team has
evaluated other disposal alternatives for
capacity contingency purposes. The
environmental and practicability screening
described in Chapter Four indicates that
Little Mystic Channel is the LEDPA for a
contingency site. The following is a PVF
evaluation for the LMC that is designed to
help identify required mitigation actions
should this site be required for excess
capacity.
Benthic Habitat: Pre-project conditions
include an opportunistic and pioneer
subtidal community of low abundance,
over the entire 15 acres. The project will
change the entire site from contaminated
subtidal substrate to clean intertidal
substrate, and therefore should provide an
opportunity for a more diverse and
abundant benthic community structure.
Shellfish/Lobster Habitat: Pre-project
conditions include the area being mapped
by EOEA (1978) as shellfish habitat, and
yielded moderate CPUE catch data for
lobster at 1.1 per trap day. The project
will establish up to 15 acres of clean soft
granular material intertidal substrate.
These conditions should enhance existing
shellfish habitat for soft-shell clams and
ribbed mussels, but will eliminate transient
lobster habitat.
Finfish Habitat: Pre-project conditions
indicate a low abundance of demersal and
pelagic species typically found in the
Boston Harbor area. The site is also
adjacent to an anadromous fish run in the
Lower Mystic River. Project activities
convert the site from transient demersal
and pelagic habitat to an intertidal fish
habitat.
Production Export: The establishment of
clean intertidal substrate should attract both
rooted and attached aquatic vegetation, and
should provide some additional, but
limited, production export function.
Sediment/Shoreline Stabilization: The
proposed intertidal conditions will continue
to function as buffeting from wave and
current energy.
Wildlife Habitat: Currently, feeding
habitat for waterfowl, dabbling and diving
birds, and some roosting sites, exist.
Project activities may pose short-termed
disruptions to existing wildlife activities,
but these should be limited in terms of
time and location. Proposed intertidal
conditions should provide additional
feeding habitat for wading and shorebirds.
However, wildlife usage is highly
dependent on areal land uses, and in this
case, urban and maritime, may limit the
amount of achievable enhancement.
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A
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Endangered Species Habitat: Endangered
species habitat does not occur at this site.
6.4.6 Resource Enhancement Concepts
Given the findings provided in the PVF,
the BHNBP should pose only limited
negative temporary effects to either the in-
channel or Little Mystic Channel PVF's.
In feet, the project as designed appears to
provide significant on-site enhancement of
project specific PVF's primarily through
the sequestering of contaminated sediments
and placement of clean substrate. Given
these findings, no compensatory resource
mitigation should be required under either
federal or state wetland regulations for the
in-channel option. Resource compensation
may be required at the LMC for
converting subtidal to intertidal habitat.
Should this contingency site be required,
consultation with the appropriate resource
agencies will identify compensatory
mitigation options. However, for the
preferred alternative, no compensatory
mitigation is required.
As local sponsor, Massport is willing to
work with state resource agencies to
identify resource enhancement
opportunities in the Harbor Area. As
examples, these can include supporting the
development of an "urban fishing park"
through rehabilitation of water access
structures to enhance public use and access
to functional, recreational fishing areas. In
addition, Massport is willing to work with
appropriate agencies to increase the
number of vessel sewage pump-out
facilities in the Harbor Area.
Summary
Massport will continue to explore resource
enhancement options, if required, during
the permitting of the project. The project
as designed contains numerous operational
mitigative measures. The preferred
disposal alternatives meets the CEQ
protocol for establishing and prioritizing
mitigation measures, and is the least
environmentally damaging alternative.
The Draft Section 61 finding included as
Chapter Eight, summarizes the mitigation
actions proposed for the project and for
meeting permit requirements identified in
the next Chapter.
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Chapter Seven: BHNIP Regulatory Status
The purpose of this section is to clearly
outline a non-exhaustive list of anticipated
permitting issues relative to mitigation,
which will require project compliance; and
the means by which the BHNIP currently
complies, or how the BHNIP proposes to
comply with all relevant jurisdictional
requirements.
7.1 LOCAL JURISDICTION
Dredging and dredge material disposal
activities will occur hi three separate
municipalities, which include the Cities of
Boston, Everett and Chelsea. In telephone
conversations with each city's conservation
commission (ConComs), on January 23
and 31, 1995, it was reported that none of
these cities have local wetland protection
bylaws. Therefore they have no apparent
mitigation jurisdiction beyond that which is
designated to them through state law and
regulation.
7.2 STATE JURISDICTION
The proposed dredging and disposal plan
occur within Designated Port Areas
(DPA's). This is significant to the
application of the Chapter 91, and coastal
zone management and state wetland
programs having jurisdiction over this
project. The DPA's are illustrated on
Figure 7-1 and 7-2.
7.2.1 Massachusetts Waterways Licensing
Program (MGL c.91 and 310 CMR Q On)
The Massachusetts Waterways Licensing
Program, dated October 4, 1990
(c. 91) defines DPA's as follows:
"Those areas designated in 310
CMR 9.24 (2) and (3) of the
Waterways Regulations
promulgated in 1978 (MGL c. 91
and 310 CMR 9.00); and are
almost completely developed areas
where few or no natural land
forms or vegetation remain. They
tend to be paved, bulkheaded, and
used for heavy industry so that
they have virtually no significance
to the interests of the Act, except
for land under the ocean." (A
Guide to the Coastal Wetlands
Regulations of the Massachusetts
Protection Act G.L. 131. s.4Q.
Cooperative Extension Service,
UMASS, Amherst, 1978, pg. 13)
As currently set forth in 310 CMR 9.04,
the following geographic areas are subject
to jurisdiction, relative to the BHNIP:
• all waterways, including flowed
tidelands; and
• all filled tidelands, except for
landlocked tidelands.
C. 91 also allows that the Massachusetts
Port Authority (Massport) "in accordance
with its Enabling Act, St. 1956 c. 465,
7-1
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may undertake certain activities within
certain geographic areas without written
authorization (emphasis added) in the form
of a license or permit from the
Massachusetts Department of
Environmental Protection (MADEP) 310
CMR 9.03 (3). Except as provided in 310
CMR 9.03 (3)(b), Massport shall obtain a
license or permit pursuant to c. 91 for any
project consisting entirely of (emphasis
added) uses other than water-dependent
industrial uses." Privately owned berths to
be dredged in the BHNIP may require
individual compliance.
While Massport may be exempt from a
requirement for written authorization, any
project that includes dredging or dredged
material disposal must comply with the
following requirements relative to DPA's
(310 CMR 9.40):
1) The design and timing of dredged
material disposal activity shall be
such as to avoid interference with
anadromous/catadromous fish runs.
At a minimum, no such activity
shall occur hi such areas between
March 15th and June 15th of any
year, except upon a determination
by the Division of Marine
Fisheries (MADMF) that such an
activity will not obstruct or hinder
the passage of fish.
2) The design and timing of dredging
and dredged material disposal
activity shall be such as to
minimize adverse impacts on
shellfish beds, fishery resource
areas, and submerged aquatic
vegetation. MADEP will consult
with the MADFM regarding the
assessment of such impacts.
Additional requirements for all dredging
and dredge material disposal projects (310
CMR 9.36 (3-5)) include requirements for
operations issues associated with dredging
and disposal. These are considered in the
Dredge Management Plan.
Finally, all projects under c. 91
jurisdiction must conform with all relevant
federal, state and local environmental
protection standards; municipal zoning and
harbor plans; and must meet all standards
to preserve water related public rights (310
CMR 9.33 through 9.35 et seq).
Massport, and the Corps are not subject to
zoning requirements. Individual, private
berth owners, however, must comply.
7.2.2 Massachusetts Wetland Protection
Act CMGL c- 131. S 40 and 310 CMR
The Massachusetts Wetlands Protection
Act and its implementing regulations
describe the performance standards within
DPA's.
Land under the ocean in DPA's plays a
role in flood control, storm damage
prevention, and the protection of marine
fisheries. The additional functions in
DPA's include support for coastal
engineering structures, such as bulkheads,
seawalls, revetments, and solid fill piers.
This support contributes to its value for
flood control and storm damage
prevention.
7-2
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Since land under the ocean is considered
the only resource impacted by the BfiNIP,
this limits protectable interests to storm
damage prevention and flood control, and
protection of marine fisheries. Activities
which could affect these interests include:
• Dredging;
• Construction of Seawalls;
• Dredge Material Disposal;
• Bulkheads and Revetments; and
• Point Discharges;
• Piers, Docks, Wharves, Floats,
• Fill; Piles and Dolphins.
These activities are typically acceptable in
DPA's. Table 7-1 lists those conditions
which must be met, in order to obtain an
Order of Conditions for these activities in
DPA's.
Revisions to dredge material disposal
compliance requirements are currently
proposed by the MADEP, Division of
Water Pollution Control (DWPC) in water
quality certification regulations (314 CMR
9.07) effective March 1, 1995. Table 7-2
is a reproduction of Table m from 314
CMR 9.07. These revised regulations
more clearly outline specific disposal
opportunities for the dredge material.
The in-channel disposal option, with clean
granular capping, is most closely
represented by confined (bulk-headed) in-
Harbor disposal and therefore may comply
with these requirements. As stated earlier
in this FEIR, portion of the BHNIP dredge
material disposal program would be to
dispose of up to 303,000 cy of silt material
at LMC, as a contingency should the
projected volume capacity of the in-
channel cells be inadequate to handle the
entire volume. This disposal alternative
will displace up to 15 acres of subtidal
estuarine resource. Chapter Four of the
FEIR/S describes the biological/ecological
resource quality as being degraded.
Should the use of this site be required to
provide additional disposal area for the
silts, these materials will be completely
sequestered from the remaining aquatic
environment. As shown in Table 7-2, this
activity may also be approvable with
effluent control.
7.2.3 MCZM Jurisdictional Review and
Policies Relative to DPA's (MGL c. 6a.
2-7 and 301 CMR 20.00^
301 CMR 20.05 sets forth the regulatory
and non regulatory policies adopted for the
MCZM project review program. Of
special significance to the BHNIP are
regulatory policies 1, 4, 5 and 7 and non-
regulatory policy 7.
Regulatory policy 1 is concerned with
protecting "... ecologically significant
resource areas (salt marshes, shellfish
beds, dunes, barrier beaches and salt
ponds) for their contribution to maritime
productivity and value as natural habitats
and storm buffers."
Regulatory policy 4 conditions construction
in water bodies ". . .to minimize
interference with water circulation and
sediment transport and to preserve water
quality and marine productivity ..."
Regulatory policy 5 extends this concern to
ensure that "... dredging and disposal of
dredged material minimizes adverse effects
on water quality, physical processes,
marine productivity and public health. "
Regulatory policy 7 encourages
location of maritime commerce and
development in segments of urban
waterfronts designated as port areas.
the
7-3
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Within these areas, prevent the exclusion
of maritime dependent industrial uses that
require the use of lands subject to tidelands
licenses."
Non-Regulatory policy 7 encourages ". .
expansion of water-dependent uses in
DPA's and developed harbors,
redevelopment of urban waterfronts and
expansion of visual access."
The intent of these policies is to ensure
that special physical and operational
requirements of uses dependent on access
to navigable channels are recognized while
not compromising environmental
resources. In addition, assigning priority
to the use of DPA's for maritime
dependent industrial development
encourages such uses to locate there.
These policies, therefore, minimize the
need for dredging new deepwater channels
elsewhere and maximize the use of prior
public investments made hi existing port
facilities.
According to MCZM policy statement and
guidance (310 CMR 20.99) all proposals
for maritime-dependent industrial
developments in DPA'S will be
encouraged by MCZM and will be
facilitated as much as possible by the
EOEA agencies, unless the proposed use
will seriously conflict with, or preempt
other existing maritime-dependent
industrial uses in that port, or other ports.
The BHNIP dredging and disposal plans
appear consistent with their CZM policies.
7.2.4 Massachusetts Division of Water
Pollution Control. Clean Water Act 401
Certification (314 CMR 9.000
Under Section 401 of the federal Clean
Water Act, an applicant proposing any
activity requiring a federal permit that will
result in a discharge to waters or wetlands
subject to federal jurisdiction is required to
obtain a state certification that the project
will comply with state water quality
standards. For purposes of Section 401,
"discharges" include the filling of "waters
of the United States" requiring a Section
404 permit under the Clean Water Act and
discharges associates with dredging and
dredged material disposal under Sections 9
and 10 of the Rivers and Harbors Act.
A 401 Water Quality Certification issued
by the Department of Environmental
Protection is a determination that the
proposed activity will not violate the
Massachusetts Surface Water Quality
Standards, as implemented by 314 CMR
9.00. The Department may, during the
course of its review of any project, attach
conditions to ensure that water quality is
protected, environmental damage is
minimized, and all other applicable state
requirements are satisfied. This
certification is necessary for the federal
permit to be valid, and any certification
conditions become conditions of the federal
permit.
The regulations also contain criteria for
dredging and dredged material disposal.
In addition to Section 404 permits for the
discharge of dredged and fill material in
wetlands, the Department must also certify
permits issued by the Corps of Engineers
to implement Sections 9 and 10 of the
Rivers and Harbors Act of 1899 for
structures or work in or affecting the
course, location, condition or capacity of
navigable waters of the United States.
Under Section 103 of the Marine
Protection, Research, and Sanctuaries Act
of 1972, the Corps of Engineers regulates
the transportation of dredged material by
7-4
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vessel or other vehicle for the purpose of
dumping it in ocean waters at designated
dumping sites. These activities also may
require a Section 401 Water Quality
Certification from the Department.
Section 307(c) of the Coastal Zone
Management Act of 1972 requires
applicants to obtain a certification or
waiver that the activity complies with the
state's coastal zone management program
for activities affecting a state's coastal
zone.
The water quality certification application
must demonstrate that the proposed action
is the preferred, practicable alternative.
Chapter Four provides a step-wise
screening approach to determine that the
in-channel option is the least
environmentally damaging alternative.
The application must also demonstrate that
all practicable steps have been taken which
will minimize potential adverse impacts.
Chapter Six presents a summary of design,
operational, and resource enhancement
options that are made part of the BHNIP to
address these concerns. In addition a fate
and transport model of all aquatic
alternatives was prepared (see Appendix F)
to compare impacts of dredging and
disposal to stringent chronic water quality
criteria. The model indicates that, with
appropriate operational scheduling, the in-
channel alternatives meets the most
stringent chronic water quality criteria.
Based on the technical information
presented in the Draft and Final EIR/S, the
BHNIP preferred alternative will comply
with the requirements for a water quality
certification.
7.3 FEDERAL JURISDICTION
Permits will be required for various
Massport activities and structures within
Corps jurisdiction, including dredging of
berth areas. The Corps administers
Section 404 of the Clean Water Act and
Section 10 of the River and Harbors Act of
1899 which regulates structures and work
in navigable waters.
All permit applications will be evaluated
by the Corps based on a public interest
review of the probable impacts of the
proposed activity and its use. 404(b)(l)
Guidelines compliance must be
demonstrated through "factual
determination" before permit issuance.
These Guidelines prohibit discharges into
aquatic areas where less environmentally
damaging practicable alternatives exist.
Table 7-3 contains the factual
determinations for all short-listed sites.
These factual determinations are based on
the findings of the current BHNIP
environmental database and the PVF
described in Chapter Six.
Once compliance is clearly demonstrated
by the applicant, the Corps can proceed
with an evaluation of public interest. The
Corps considers the following criteria,
among others in evaluating an application:
the need for the project; practicability of
reasonable alternatives and the beneficial
and or detrimental effects.
The Federal portion of the project also
requires compliance with the 404(b)(l)
guidelines. This FEIR/S is intended to
serve both the Massport berth dredging
project and the Federal portion of the
BHNIP.
7-5
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Designated Port Area:
EAST BOSTON
Scale In Yards
0 1000
DESIGNATED PORT AREA CONSISTS OF:
Selected area wilhln those waters
subject te Waterways license jurisdiction
(seaward of mean high waler mark)
Priority area (or stale and federal funding
(landwaid of mean high water mark)
CHARLES-
TOWN
NOMHlll«lllOc««lSlirv«vmu»Ci,J«n. 1070
Designated Port Area:
SOUTH BOSTON
DESIGNATED PORT AREA CONSISTS OF:
Scale In Yards
1000
Selected area wilhin Ihose walers
subject to Waterways license jurisdiction
(seaward of mean high waler mark)
Priority area (or stale and federal funding
(landward of mean high waler mark)
HOAAH«lloiulOc«»1 Survey HUKUCMaHWTl.Jui. 1878
FIGURE 7-1: PROJECT SPECIFIC DESIGNATED PORT AREAS
-------
Designated Port Area:
MYSTIC RIVER
DESIOHATEO PORT ABEA CONSISTS OF:
ScatolnYWds
600
StMtd via vrfiNn Ihosi w»l«»
iub)«l lo Wwwiyi tcint* (wMolta
s/J ol main Ngh wilw muk)
Prtwlly ut« tor tula «nd Ixliril funding
(Iwdwaid ol mun Ugh wilir mtdi)
A EVERETT
CHARLESTOWN
NOAAmiCTiHOeilnSorviyH»ulicMlOc»inS«viyN»lllic
-------
Activity
TABLE 7-1: ACCEPTABILITY CONDITIONS FOR ACTIVITIES WITHIN DPA'S
Interest to be Protected
Adverse Effects to Interest
Conditions Required to Meet
Performance Standards
Dredging
Protection of marine fisheries
Storm damage prevention and flood
control
• Dredging may adversely affect water
circulation by creating areas of
stagnation
• Dredging may adversely affect water
quality by changing dissolved oxygen,
temperature, turbidity, or by stirring
up pollutants in the bottom sediments.
A high concentration of certain
pollutants in the bottom sediments,
such as PCB's or heavy metals, may
preclude the possibility of dredging
under the regulations of the Division
of Water Pollution Control (DWPC).
• Extensive dredging of a port area may
increase wave height, which may
increase their potential destructive
energy.
• Dredge channel and port area so that
all portions of them will be adequately
flushed by the tides.
• Complete the dredging operation as
quickly as possible by using the most
efficient and practical equipment.
• Where possible, schedule dredging so
as not to conflict with fisheries use.
• Bottom sediment analysis and
evaluation of dredging should be
coordinated with the DWPC.
• Minimize the amount of dredging.
• Whenever possible, channel axis should
not be parallel to direction of major
storm waves.
-------
TABLE 7-1;
Activity
Dredge Material Disposal
EPTAB1LITY CONDITIONS FOR ACTIVITIES WlTinNDPAJSJ
Advene Effects to Interest
Interest to be Protected
Storm damage prevention and flood
control
Protection of marine fisheries
1 Diiposal of dredged material may
cause shoaling of netrahore land under
ocean which will interrupt sediment
transport processes, thereby affecting
the volume and form of coastal
beaches.
> Disposal of clean dredged material may
cause the shoaling of ncarshore land
under the ocean which can create areas
of stagnation.
• Disposal of clean dredged material can
alter the distribution of sediment
grain size.
• Disposal of clean dredged material may
bury eel grass beds.
Conditions Required to Meet
Performance Standards
« Wave height at any point along the
shoreline thall not increase by more
than 10% by disposal of dredged
material on nearshore areas of land
under ocean.
> Disposal of spoil in discontinuous
bands, interrupted at least every 250 ft.
by 50 ft. breaks to provide for passage
of water, nutrients and aquatic life.
(These figures are guidelines only; the
concept should be adjusted as'necessary
in the particular project).
• Dredged material disposal on any
portion of land under the ocean shall
have a mean grain size distribution
which does not differ from the existing
land under the ocean sediment grain
size by more than 50% .
• Disposal of dredged material should
avoid eel grass beds to the maximum
extent possible.
-------
TABLE 7-1; ACCEPTABILITY CONDITIONS FOR ACTIVITIES WITHIN DPA'S (continued)
Activity
Interest to be Protected
Adverse Effects to Interest
Conditions Required to Meet
Performance Standards
Fill
Protection of marine fisheries
• The process of placing fill behind
or within seawalls or bulkheads may
cause turbidity and sedimentation.
• Pollutants which may be present in the
fill may be leached out into or
resuspended in the water column.
» Fill must be contained within a
seawall, bulkhead, or revetment
permitted by the Regulations.
• The area to be filled shall be dewatered
prior to placement of the fill or a silt-
ation curtain shall be placed immediate-
ly around the retaining structure to
contain the material suspended in the
water displaced as the area is filled,
where conditions permit.
• Only clean fill may be permitted (see
description of clean fill in the water-
ways (c. 91) regulations.
Seawalls, Bulkheads, and Revetments
Protection of marine fisheries
Storm damage prevention and control
• Construction of seawalls, bulk-
heads and revetments are likely to
adversely affect water quality by
generating turbidity in the area.
• The placement of seawalls, bulk-
heads and revetments within the DPA's
is not likely to have an adverse effect to
storm damage prevention and flood ,
control.
* The construction should be
accomplished as quickly as possible
using the most efficient and practical
equipment.
• No conditions are necessary
03
-------
AcUvily
Interest to be Protected
Adverse Effects to Interest
Conditions required to Meet
Performance Standards
Point Discharges (de-watering)
Protection of marine fisheries
• Runoff from roadi and parking loti or
other paved surfaces contain* poJIut-
anti such as oil, grease, heavy metals
and participate matter, (hereby
adversely affecting waler quality.
Storm damage prevention and flood
control
» Headwall and support may interrupt
sediment transport.
• Sedimentation or catch basins as
appropriate to the amount of runoff.
» Gas trips.
• Periodic maintenance and cleaning of
the basins and traps.
• Periodic cleaning of debris from paved
surfaces.
* Headwall and supports must be spaced
so that sediment transport is not
interrupted,
Piers, Docks, Wharves, Floats, Piles
mid Dolphius
Storm damage prevention and flood
control
Protection of marine fisheries
• Piers, piles, etc., are unlikely to
have an adverse effect on storm
damage prevention in DPA's.
• Piers, piles, etc., which are too close
together may alter water circulation and
cause areas of stagnation, thereby
adversely affecting water quality.
• Installation of piles, piers, etc., may
cause turbidity and sedimentation
during the construction process.
• No conditions are necessary.
• Space piles as far apart as practical
for the structure being built, in no
case less than 10 feet apart.
• Construction shall be completed as
quickly as possible to minimize the
amount of turbidity and sedimentation.
Information contained in this table from: ... t,..AOO A_,I,-,,. io7«
A Guide to Coastal Wetlands Regulation, nf the Massachusetts Wetlands Protection Act G.L. 131. s.4Q, Cooperatwe Extension Serv.ce, UMASS, Amherst, 1978.
-------
TABLE 7-2: NORMALLY APPROVABLE DREDGING HANDLING AND DISPOSAL OPTIONS
Chemical Type (Table I)
Physical Type (Table H)
DREDGING METHODS
Hydraulic
Mechanical
DISPOSAL METHODS
Hydraulic: Sidecast
Hydraulic: Pipeline
Mechanical: Sidecast
Mechanical: Barge
PLACEMENT
Land or in-harbor disposal with
bulk-heading
Open ocean disposal at high
energy, sandy sites
Open ocean disposal at low
energy, sandy sites
Unconfined in-harbor
Beach Replenishment
OTHER CONDITIONS
Timing and placement to
Avoid Fisheries Impacts
(spawning and running periods
and areas)
Category One
A
B
C
X
X
X
X
X
X
Category Two
A
B
C
X
X
X
X
X
X
Category Three
A
B
C
X
X
X
X
X
X
X
X
0
X
X
(<0
X
X
X
X
O
X
0
X
(a)
O
X
O
0
(a)
O
.<»
O
O
(c)
(<0
0
X
O
X
O
X
O
X
(a)
O
O
O
O
(a)
0
(b)
O
O
(<0
(c)
0
X
0
X
O.
X
O
X
X
X
X
X
O
X
O
X
(a)
O
(b)
O
O
(c)
(a)
O
(b)
O
O
(a)
O
(b)
O
O
(o)
(c)
O
X
O
X
(a)
0
(b)
O
O
(c)
Legend X = Normally approvable
O = Not normally approvable
(a) = Normally approvable but control of effluent will be required
(b) = Approvable only after bioassay, performed in accordance with established EPA procedures, indicates no significant
biological impact. A statistically comparable project which has successfiilly passed the bioassay test may be substituted. If a
significant biological impact is found, this material is unsuitable for open water disposal.
(c) = Required in all cases
-------
TABLE 7-3 FACTUAL DETERMINATION: IN-CHANNEL SITES
LOttO-TWM
commons
SHORT-TERM
CONDITIONS
EXISTING
CONDmONS
Clean parent materiil will evcnturfly bo covered with new
illu from point and non-point discharges.
Pott-dredge and di»poul tubitrate will bo
clean parent and/or capping materfil (clay
or Band).
Contaminated tilt overlying clean parent
material (clay).
No additional impacts are anticipated.
No impacts anticipated.
150 billion gallon (idol prism.
WATER CIRCULATION,
FLUCTUATION, AND
SALINITY
CONTAMINANTS
AQUATIC ECOSYSTEM
SECONDARY EFFECTS
Claw SB water (314 CMR 4.05-4.06), on
urbanized estuarine condition.
Class SB water (314 CMR 4.05 -4.06), silts
are considered contaminated, parent material
and rock considered clean.
Opportunistic/pioneer benlhic community,
marginally significant transient fishery and a
fish run.
Open water site with no existing mixing zone.
700 mg/1 ® surface for up tp 600 m,
1,100 mg/l ® bottom for up tp 1000
m, (LnSalle eta! 1991); any plume should
rapidly dissipate.
Low potential for substantial degredation
of ambient water quality, substrate
conditions should greatly improve with
the removal of the contaminated silts.
Should return to Clan SB water in an urbanized estuarine
condition.
As future siltalion proceeds, the substrate condition will to
deteriorate.
Denlhic substrate is currently degraded due to
the on-going silling of the harbor and the
contaminated point and non-point discharges to
the harbor.
•••••^—•—'
Contaminated sills will remain exposed as the
bottom substrate in the inner harbor and
berthing areas.
Opportunistic/pioneer species should
recolonize and rework new substrate
material, transient aquatic macrofauna
should return following dredging
activities, there are some losses to finfish
expected due to blasting of rock.
During disposal activities, isolated with
silt curtains/barriers, a vertical mixing
zone will include the water column
overlying the pit; localized and temporary
turbidity events should dissipate rapidly.
Opportunistic/pioneer species should recolonize and
rework new aubslrate material, transient aquatic
macrofauna should return following dredging activities,
there are some losses to finfish expected due to blasting of
rock.
No additional impacts are anticipated.
Dredging and capping of In-channel
disposal cells will expose clean parent
material as new substrate.
Creation of 116 acres of clean parent
material intertidal habitat will replace
degraded intertidal and subtidal
conditions; opportunistic and pioneer
species should naturally recruit to the area
and rework new sediments; limited hard
substrate habitat will remain; and finfish
utilization will be limited to periods of
inundation.
As future siltalion proceeds, the substrate condition will
continue to deteriorate.
Biological communities and habitats should further
improve with the on-going improvements to the Boston
Harbor System and water quality.
-------
TABLE 7-3 (CON'T) FACTUAL DETERMINATION: AMSTAR SITE
404(B)(1)
GUIDELINES
EXISTING
CONDITIONS
SHORT-TERM
CONDITIONS
LONG-TERM
CONDITIONS
SUBSTRATE
Three types of existing intertidal substrate;
hard substrate (pilings and seawalls),
gravel/cobble beach, and boulders; also 3.5
acres of category III gray silly/clays.
Creation of 3.5 acres of clean parent
material intertidal habitat will replace
degraded intertidai and subtidal
conditions; opportunistic and pioneer
species should naturally recruit to the area
and bioturbate new sediments.
Intertidal habitat should should be limited by surrounding
conditions, no additional impacts are anticipated.
WATER CIRCULATION,
FLUCTUATION, AND
SALINITY
Circulation at Amslar influenced by tidal
exchange.
Less exchange since bottom elevation will
be increased, will remain intertidal.
No additional impacts anticipated.
TURBIDITY/TSS
Class SB water in an urbanized estuarine
condition.
Localized and temproary impacts are
anticipated during the disposal operation
at Amslar, silt curtains should isolate
turbid conditions to a limited area.
Siltation curtains and barriers should remain and be
maintained until any turbidity plume dissipates, and poses
little to no risk to receiving waters,
CONTAMINANTS
Class SB water in an urbanized eshiarine
condition.
Sequestering of 128,000 cy of silt should
isolate contaminate from the Mystic River
environment.
No additional impacts anticipated,
AQUATIC ECOSYSTEM
Existing conditons include barnacle, mussel,
green algae and Fucus sp. on hard substrate;
polychaetes, oligochaetes and nematodes in the
soft substrate; and the protected waters within
the berthing area provide finfish refuge and
forage habitat.
Loss of subtidal substrates will displace
existing benthic invertebrates (polychaetes
and oligochaetes and nematodes), reduce
productivity of barnacles, mussels and
green algae; flnflah utilization will also be
altered, and limited to periods of tidal
inundation.
Creation of 3.5 acres of clean parent material intertidal
habitat will replace degraded intertidal and subtidal
conditions; opportunistic and pioneer species should
naturally recruit to the area and rework new sediments;
limited hard substrate habitat will remain; and finfish
utilization will be limited to periods of inundation.
MIXING ZONE
Abandoned berthing area with no existing
mixing zone.
During disposal activities, isolated with
silt curtains/barriers, a vertical mixing
zone will include the entire and subtidal
water columns within the site, and
turbidity should settle end/or slowly be
diluted by tidal circulation.
Siltation curtains and barrier should remain and be
maintained until any turbidity plume dissipates, and poses
little to know risk to receiving waters.
CUMULATIVE EFFECTS
Benthic substrate is currently degraded due to
the on-going silling of the harbor system, and
the contaminated point and non-point
discharges.
Sequestering of 128,000 cy of
contaminated silts over 3.5 acres of
degraded benlhic habitat, and a
permanenet loss of 3,5 acres of subtidal
habitat.
Creation of 3.5 acres of clean parent material intertidal
habitat will replace degraded intertidal and aubtidal
conditions; opportunistic and pioneer species should
naturally recruit to the area and rework new sediments;
limited hard substrate habitat will remain; and finfish
utilization will be limited to periods of inundation.
SECONDARY EFFECTS
Site remains in an abandoned, degraded
condition; with a potential for future
development.
Creation of 3.5 acres of clean parent
material intertidal habitat wilt replace
degraded intertidal and subtidal
conditions; opportunistic and pioneer
species should naturally recruit to the area
and rework new sediments; limited hard
substrate habitat will remain; and finfish
utilization will be limited to periods of
inundation.
Biological communities and habitats should further
improve with the on-going improvements to the Boston
Harbor System and water quality.
-------
TABLE 7-3 (COIfT) FACTUAL DETERMINATION: BOSTON LIGHTSHIP SITE (BLS)
GUIDELINES
BXOTOTC
commons
SHORT-TERM
commons
SUBSTRATE
Sedimentary md depoiillowl environment
dominated muddy iindi «nd mud; htitortc
dtipoial Indicate* that hiztrdoiii utd low
level rodiotclive wMtei tre praent it lh«
lite.
Dcpoiilion of silt ind city should be
compatible with exttllng tubiUtte
variability ind cbtncter; uneonfined
dlipoul will compound hutorio
contamination problems.
Unsecured contmbtted lilti m»y hive limiting effect*
an Individuals recoloniztng the dlipowJ arei; riiki ire
anticipated to be limited.
WATER CIRCULATION,
FLUCTUATION AND
SALINITY
Open ocean circulation Influenced by lldea
and windi.
Change) in bottom contours should not
alter existing surface water hydrology.
No additional impact* are anticipated.
TURBIDITY/TSS
CONTAMINANTS
AQUATIC ECOSYSTEM
MIXING ZONE
CUMULATIVE EFFECTS
SECONDARY EFFECTS
Class SA water Quality, limited turbidity.
Surface waters appear relatively free of
contaminant, but sediments are suspected of
being contaminated with hazardous and low-
level radioactive wastes.
Sediments are dominated by an
amphipod/polychaete, nemertean worm and
burrowing anemone community; and both the
lobster and finfish community are significant
and representative of a typical Gulf of Maine
fishery.
Open water site with no existing mixing
An area of potentially degraded sediments
which is heavily fished commercially.
Availability of suitable disposal areas are
limited, therefore non-use could limit future
disposal options.
& 700 mg/l @ itirface for up Ip 600 m,
£ 1,100 mg/l @ bottom up tp 1000 m,
(LaSalle ctal 1991); any plume should
rapidly dissipate.
Project specific modelling
(REFERENCE) indicates that limited
water quality degradation should be
anticipated during disposal, in the worst
case, degredation should be limited and
rapidly dissipated within hours of
disposal.
A portion of the benthic resources should
be lost during disposal activities, but
should rapidly recolonize following the
activities, lobster and finfish resources
should evacuate the area during
operations and should also return
following the cessation of activities.
During open water disposal the vertical
mixing you will include the water
column overlying the target area,
localized and temporary turbidity events
should dissipate rapidly.
Disposal of -- cy of contaminated silt
should have limited effects on areal
water quality; these activities will cause
short term reductions on fishery
resources, abundances and diversity.
Current and documented fishing
activities (commercial and recreational)
would be interrupted during the disposal
operations.
No additional impacts ore anticipated.
Since BLS is suspected of containing unsecured wastes,
the addition of contaminated silts from BHNIP should
have little addlional effects to the area.
As the regenerating ecosystem develops, the fishery
community should also respond with greater abundance
and diversity.
No additional impacts are anticipated.
Unsecured contaminated silts may have limited, but
continued effects on individuals recolonizing the disposal
area; risks are anticipated to be limited.
Use of the site for future maintenance dredge material
disposal could periodically interrupt offshore fishing
activities.
-------
TABLE 7-3 (CON'T) FACTUAL DETERMINATION: LITTLE MYSTIC CHANNEL (LMC)
404(B)(1)
GUIDELINES
EXISTING
CONDITIONS
SHORT-TERM
CONDITIONS
LONG-TERM
CONDITIONS
SUBSTRATE
Fine grained sill/clay with elevated
metal levels (Category II and IH-314
CMR 9.00), and elevated levels of
PAH's, TPH.8 and PCB's.
Temporary loss of 153 acres of existing substrate, replaces with
clean parent material capping and sequestering contaminated
dredge material and existing substrate.
Cap material placed at the site should be
quickly recolonized and reworked.
WATER
CIRCULATION,
FLUCTUATION
AND SALINITY
Circulation in LMC is influenced by
tidal exchange, six discharge pipes and
aCSO.
No impacts are anticipated.
No additional impacts are anticipated.
TURBIDITY/TSS
Class SC water (314 CMR 4.05-4.06),
an urbanized estuarine condition.
Localized and temporary impacts are anticipated during disposal
operations in LMC, silt curtains should isolated turbidity within
a limited area.
No additional impacts are anticipated.
CONTAMINANTS
Class SC water (314 CMR 4,05-4.06),
an urbanized estuarine condition;
depressed DO; and polyhaline.
Post disposal substrate will be clean parent and or capping
material (clay or sand), over 15.3 acres of existing benthic
substrate; contaminants should be sequestered.
No additional impacts are anticipated.
AQUATIC
ECOSYSTEM
Benthic infauna include oligochaetes,
polychaetes and nematodes; limited
lobster; and several finfish are
associated with the main ship channel,
and should move in and out of LMC.
Benfhic infauna impacts should be temporary and recolonization
of opportunistic/pioneer species should occur in the capping
material; motile species will evacuate the work area and those
not limited by depth requirements should return post activity.
Creation of 15.3 acres of clean parent
material intertklal habitat will replace
degraded intertidal and subtidal conditions;
opportunistic and pioneer species should
naturally recruit to the area and bioturbate
new sediments; limited hard substrate habitat
will remain; and finfish utilization will be
limited to periods of indundation.
MIXING ZONE
Open water site with no existing mixing
zone, but adjacent to shore-based'
discharge/ CSO's.
During disposal activities, isolated with silt curtains/barriers, a
vertical mixing zone will include the entire and subtidal water
columns within the site, and turbidity should settle and/or slowly
be diluted by tidal circulation.
Sillation curtains and barrier should remain
and be maintained until any turbidity plume
dissipates, and poses little to know risk to
receiving waters.
CUMULATIVE
EFFECTS
Benthic substrate and water quality are
currently degraded due to the on-going
silting of the harbor, and the
contaminated point and non-point
discharges to the harbor.
Disposal and sequestering contaminated silts and capping, over
the existing degraded substrate will provide clean substrate for
recolonization.
Creation of 15.3 acres of clean parent
material intertidal habitat will replace
degraded intertidal and eubtidal conditions;
opportunistic and pioneer species should
naturally recruit to the area and rework new
sediments; limited hard substrate habitat will
remain; and finfish utilization will be limited
to periods of indundation.
SECONDARY
EFFECTS
Site remains in an abandoned, degraded
condition; with a potential for future
development.
Creation of 15.3 acres of clean parent material intertidal habitat
will replace degraded intertidal and subtidal conditions;
opportunistic and pioneer species should naturally recruit to the
area and rework new sediments; limited hard substrate habitat
will remain; and finfish utilization will be limited to periods of
indundation.
Biological communities and habitats should
further improve with the on-going
improvements to the Boston Harbor System
and water qualify.
-------
TABLE 7-3 (CON'T) FACTUAL DETERMINATION; MASSACHUSETTS BAY DISH>SAL SITE (MBDS)
ouiDBums
CONDITIONS
SH'OKT-TSRH
commons
commons
SUBSTRATE
A permitted open oceut dlirxmt ills with
varying fedlmml chmnclcriiU'ci and quality;
subject of hbtoric dupoiil, ttndy «llt tnd fine
«llt/et«y nuiflnf from low to high leveti of
v«riom eontamlrtinti.
Continual variable texture and quality.
No tddttlanal Impacts ire anticipated.
WATER CIRCULATION,
FLUCTUATION AND
SALINITY
Open ocenn circulation Influenced by tidu and
wlndi.
Chinfei in bottom contours at this deep
water lite should not oiler existing surface
water hydrology.
No additional impacts are anticipated.
TURBIDITY/TSS
Open ocean water coruidcrcd relatively clean,
therefore limited turbidity.
£ 700 mg/l @ surface for up tp 600 m,
£ 1,100 mg/l © bottom for up tp 1000
m, (LaSalle eta! 1991); any plume should
rapidly dissipate.
No additional impacts are anticipated.
CONTAMINANTS
Surface waters appear relatively free of
contaminants, but sediments contain levels
ranging from low to high relative to various
contaminants.
Project specific modelling
(REFERENCE) indicates that limited
water quality degredation should be
anticipated during disposal, in the worst
case, degredation should be limited and
rapidly dissipated within hours of
disposal; unsecured contaminated silts
may have limited, but continued effects
on individuals rccolonizing MBDS, risks
are anticipated to be limited.
Since MBDS contains unsecured wastes, the addition of
unsecured or capped contaminated silts from BHNIP
should have little additional effect to the habitats of this
permitted disposal site.
AQUATIC ECOSYSTEM
Sediments are dominated by a variety of
polychaetes and oligochaetes; both the lobster
and finfish comminilies are significant and
representative of a typical Gulf of Maine
fishery wilh some southern influences.
A portion of the benthic resources should
be lost during disposal activities, but
should rapidly recolonize following
operations; lobster and finfish resources
should evacuate the area during
operations and should also return
following the cessation of activities.
As the regenerating ecosystem develops, the fishery
community should also respond with greater abundance
and diversity.
MIXING ZONE
Open water site with no existing mixing zone.
During open water disposal the vertical
mixing you will include the water column
overlying the target area, localized and
temporary turbidity events should
dissipate rapidly. ^^
No additional impacts are anticipated.
CUMULATIVE EFFECTS
An area of degraded sediments which is
heavily fished commercially.
Disposal of clean parent materials should
have limited effects on areal water
quality; these activities will cause short
termreductions on fishery resources,
abundances and diversity.
Unsecured contaminated silts may have limiting effects on
individuals recolonizing MBDS, risks are anticipated to be
limited.
SECONDARY EFFECTS
Availability of suitable disposal areas are
limited, therefore non-use could limit future
disposal options.
Current and documented fishing activities
(commercial and recreational) would be
interrupted during the disposal operations.
Use of the site for future maintenance dredge material
disposal could periodically interrupt offshore fishing
activities.
-------
TABEL 7-3 (CON'T) FACTUAL DETERMINATION: MEISBURGER 2
404(B)(1)
GUIDELINES
SUBSTRATE
WATER CIRCULATION,
FLUCTUATION AND
SALINITY
TURBHMTY/TSS
CONTAMINANTS
AQUATIC ECOSYSTEM
MIXING ZONE
CUMULATIVE EFFECTS
SECONDARY EFFECTS
EXISTING
CONDITIONS
Clean sand and gravel, appears
suitable for beach nourishment and
capping.
Open ocean circulation influenced by
tides, winds and major riverflow.
Class SA water quality, limited
turbidity.
Surface waters and sediments appear
relatively free of contamination.
Sediments dominated by
amphipod/polychaete assemblage,
lobster appear significant to the area,
and the fuifish community is
significant and comprised of typical
Gulf of Maine demersal and pelagic
structure with some southern
influences (NA 1995).
Open water site with no existing
mixing zone.
An area relatively free of
contaminants, which is heavily fished
commercially.
Availability of suitable disposal areas
are limited, therefore non-use could
limit future disposal options.
SHORT-TERM
CONDITIONS
Material disposal would occur and be
contained within a borrow pit and capped with
clean parent material and the final cover would
be a portion of the sand and gravel removed
during the pit construction; and therefore
would be similar to existing conditions,
Underwater contours would be returned to pre-
project conditions, with the final capping of
sand and gravel,
S 700 mg/l @ surface for up tp 600 m, <,
1,100 mg/l @ bottom for up tp 1000m,
(laSalle etal 1991); any plume should rapidly
dissipate.
Project specific modelling (REFERENCE)
indicates that limited water quality problems
should be anticipated during pit construction
and moreover, during disposal; in the worst
case degedation should be limited and rapidly
dissipated and diluted.
Benthic community will be completely lost
during pit construction, but should recolonize
the final cap after disposal operations are
completed, lobster and finflsh resources should
evacuate the area during operations and should-
also return to the area followng the cessation
of activities.
During open water disposal the vertical mixing
you will include the water column overlying
the target area, localized and temporary
turbidity events should dissipate rapidly.
Sequestering of 10* - 10' cy of dredged
material and future maintenance material
within the borrow pit, capped with clean
parent material will have limited effects on
areal water quality, which will occur only
during project activites; these activities will
cause short term reductions on fishery
resources, abundance and diversity.
Current and documented fishing activities
(commercial and recreational) would be
interrupted during the disposal operations.
LONG-TERM
CONDITIONS
No additional impacts are anticipated.
No additional impacts are anticipated.
No additional impacts are anticipated,
No additional impacts are anticipated.
As the regenerating ecosystem develops, the fishery
community should also respond with greater numbers and
diversity. »
No additional impacts are anticipated.
As the regenerating ecosystem develops, the fishery
community should also respond with greater numbers and
diversity.
Use of the site for future maintenance dredge material
disposal could periodically interrupt offshore fishing
activities.
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TABLE 7-3 (CON'T) FACTUAL DETERMINATION: MEISBURGER7
GUIDEUNBS
OUSTING
commons
SHORT-TERM
commons
LONG-TERM
commons
SUBSTRATE
Clan land and travel, ippun tuifible
for beich nourishment and cupping.
Miteriil dlipoul would occur »nd be contained
wiihln a borrow pit tnd c»pped with clean parent
nutcrial «nd (ho final cover would be a portion
of (he Mfld wvd gravel removed during the pit
commotion; and therefore wotiM be limilar to
exliting conditions.
No addition*! impacts are anticipated.
WATER CIRCULATION,
FLUCTUATION AND
SALINITY
Open ocean circulation influenced by
lido, winds and major riverflow.
Underwater contours would be returned to pre-
project condition!, with the final capping of sand
and grovel.
No additional Impacts are anticipated.
TURBOHTY/TSS
Clnis SA water quality, limited
turbidity.
£ 700 mg/l @ surface up tp 600 in, £ 1,100
mg/l ® bottom for up tp 1000 ra, (LaSnlle etal
1991); any plume should rapidly dissipate.
No additional impact! are anticipated.
CONTAMINANTS
Surface waters and sediments appear
relatively free of contamination.
Project specific modelling (REFERENCE)
indicates that limited water quality problems
should be anticipated during pit construction and
moreover, during disposal; in the worst case
degedation should be limited and rapidly
dissipated and diluted.
No additional impacts are anticipated.
AQUATIC ECOSYSTEM
Sediments dominated by
amphipod/polychaete assemblage,
lobster appear significant to the area,
and the finfish community is significant
and comprised of typical Gulf of Maine
demersal and pelagic structure with
some southern influences (NA 199S).
Denthic community will be completely lost
during pit construction, but should recolonize the
final cap after disposal operations are completed,
lobster and finfish resources should evacuate the
area during operations and should also return to
the area followng the cessation of activities.
As the regenerating ecosystem develops, the fishery
community should also respond with greater numbers and
diversity.
MIXING ZONE
Open water site with no existing mixing
zone.
During open water disposal the vertical mixing
you will include the water column overlying the
target area, localized and temporary turbidity
events should dissipate rapidly.
No additional impacts are anticipated.
CUMULATIVE EFFECTS
An area relatively free of contaminants,
which is heavily fished commercially.
Sequestering of up to 19.5 million cy of material
and future maintenance material within the
borrow pit, capped with clean parent material
will have limited effects on areal water quality,
which will occur only during project activities;
these activities will cause short term reductions
on fishery resources, abundance and diversity.
As the regenerating ecosystem develops, the fishery
community should also respond with greater numbers and
diversity.
SECONDARY EFFECTS
Availability of suitable disposal areas
are limited, therefore non-use could
limit future disposal options.
Current and documented fishing activities
(commercial and recreational) would be
interrupted during the disposal operations.
Use of the site for future maintenance dredge material
disposal could periodically interrupt offshore fishing
activities.
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TABLE 7-3 (CON'T) FACTUAL DETERMINATION: MYSTIC PIERS 49-50
404(B)(1)
GUIDELINES
SUBSTRATE
WATER CIRCULATION,
FLUCTUATION AND
SALINITY
TURBIDITY/TSS
CONTAMINANTS
AQUATIC ECOSYSTEM
MIXING ZONE
CUMULATIVE EFFECTS
SECONDARY EFFECTS
EXISTING
CONDITIONS
Contaminated silt overlying clean parent material.
Circulation influenced by tidal exchange.
Class SB water in an urbanized estuarine condition.
Contaminated silt overlying clean parent material.
Area! opportunistic/pioneer benthic community, fairly
significant transient and brood fishery, and fish run in
adjacent river habitat.
Abandoned berthing area with no existing mixing
zone.
Benlhic substrate is currently degraded due to the on-
going silting of the harbor system, and the
contaminated point and non-point discharges.
Site remains in an abandoned, degraded condition;
with a potential for future development.
SHORT-TERM
CONDITIONS
Displacement of 2.7 acres of contaminated silly
substrate.
Entire watersheet area lost to fastland.
Sheet pile bulkhead and dewatering, limited
turbidity when the bulkhead Is driven.
Sequestering of 98,000 cy of contaminated silts
over 2.7 acres of degraded benthic substrate.
Permanent loss of 2.7 acres of aquatic habitat.
Mixing zone will be limited to any temporary or
permanent dewatering outfall to the Mystic River;
any plume should be limited and rapidly dissipated.
Sequestering of 98,000 cy of contaminated silts
over 2.7 acres of degraded benthic substrate, and a
permanent loss of 2.7 acres of aquatic habitat.
Dewatering discharges.
LONG-TERM
CONDITIONS
Sequestering of 98,000 cy of contaminated silts
over 2.7 acres of degraded benthic substrate.
No additional impacts are anticipated.
No additional impacts are anticipated.
No additional impact are anticipated.
Permanent loss of 2.7 acres of aquatic habitat.-
No additional impacts are anticipated.
'•ey,-l
Permanent loss of 2.7 acres of aquatic habitat.
On-going maintenance of bulkheading to eliminate
potential of seeps or releases of sequestered
materials,
I
h
o
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1*1
TABLE 7-3 (CON'T) FACTUAL DETERMINATION: RESERVED CHANNEL (RQ AREA A
GUlDWtfSS
EXISTING
coNDtnotis
SHORT-TEW
commons
WW-TBW
commons
SUBSTRATE
Ony/bltck lilt and city, contuntmled
iub>Inile (category II wid III).
Temporary lou of 8.9 teret of exfotinf
lubilrato, replaced with ol**n pircnt rotteritl
cipping and icqucilcruig condflttntted dredge
mnttriil and exliting lubttntle.
Cip mtteri*! placed «t lite it!e should be quickly
reeotonfeed and reworked.
WATER CIRCULATION,
FLUCTUATION AND
SALINITY
Circulation In RC is Influenced by
tidal exchange and three CSO'i.
Sewer outfit! would need to be relocated, no
other impacts are anticipated,
No additional impact! are anticipated.
TURBIDITY/TSS
Class SC water (314 CMR 4.05-4.06),
an urbanized estuarine condition.
Localized and temporary impacts are anticipated
during diiposal operation in RC, lilt curtains
should isolate turbid conditions to « limited
No additional impacts are anticipated.
CONTAMINANTS
Gray/black silt and clay, contaminated
eubatrete (category II and III); clou
SC water (314 CMR 4.05-4.06), an
urbanized ettuarine condition.
Sequestering of 14,000 cy of silt should isolate
contaminntj from the areal environment.
No additional impacts are anticipated.
AQUATIC ECOSYSTEM
Piles, granite seawalls, floating docks
and metal bulkheads support green
algae, Fucussp., barnacles, and
periwinkles; soft sediments contain
oligochaetes, polychaetes and
nematodes; finfish habitat is present,
but appears limited to transient use,
although flounder spawning habitat
may be present.
Loss of subtidal substrates displacing existing
benthic invertebrates (poychaetes, oligochaetes
and nematodes), reduce productivity of
barnacles, mussels and algae; finfish utilization
will also be altered, and limited to periods of
tidal inundation; any flounder spawning habitat
will be lost.
Creation of 8.9 acres of clean parent material intertidal
habitat will replace degraded intertidal and subtidal
conditions; opportunistic and pioneer species should
naturally recruit and bioturbate new sediments; limited
hard substrates will remain; and finfish utilization will be
limited to periods of tidal inundation.
MIXING ZONE
Open water site with no existing
mixing zone, but adjacent to shore-
based discharge/CSO's.
During disposal activities, isolated with silt
curtains/barriers, a vertical mixing zone will
include the entire intertidal and subtidal water
columns within the site, and turbidity should
settle and/or slowly be diluted by tidal
circulation
Siltation curtains and barriers should remain and be
maintained until any turbidity plume dissipates, and poses
little to no risk to receiving waters.
CUMULATIVE EFFECTS
Benthic substrate is currently degraded
due to the on-going silting of the
harbor system, and the contaminated
point and non-point discharges.
Sequestering of 14,000 cy of contaminated silts
over 8.9 acres of degraded benthic habitat, and
a permanent! loss of 8.9 acres of subtidal
habitat.
Creation of 8.9 acres of clean parent material intertidal
habitat will replace degraded intertidal and subtidal
conditions; opportunistic and pioneer species should
naturally recruit and rework new sediments; limited hard
substrates will remain; and finfish utilization will be
limited to periods of tidal inundation.
SECONDARY EFFECTS
Site remains in an abandoned,
degraded condition; with a potential
for future development.
Creation of 8.9 acres of clean parent material
intertidal habitat will replace degraded intertidal
and subtidal conditions; opportunistic and
pioneer species should naturally recruit and
rework new sediments; limited hard substrates
will remain; and finfish utilization will be
limited to periods of tidal inundation,
Biological communitiea and habitats should further
improve with the on-going improvements to the Boston
Harbor System and water quality.
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TABLE 7-3 (CON'T) FACTUAL DETERMINATION: RESERVED CHANNEL (RC) AREA B
404(B)(D
GUIDELINES
EXISTING
CONDTTIONS
SHORT-TERM
CONDITIONS
LONG-TERM
CONDITIONS
SUBSTRATE
Gray/black silt and clay, contaminated
substrate (category II and HI),
Temporaiy loss of 7.7 acres of existing
substrate, replaced with clean parent material
capping and sequestering dredge material and
existing substrate.
Cap material placed at the site should be quickly
recolonized and reworked.
WATER CIRCULATION,
FLUCTUATION AND
SALINITY
Circulation in RC is influenced by
tidal exchange and three CSO's.
Sewer outfall would need to be relocated, no
other impact* are anticipated.
No additional impact) are anticipated.
TURBIDITY/TSS
Class SC water (314 CMR 4.05-4.06),
an urbanized estuarine condition.
Localized and temporary impacts are anticipated
during disposal operation in RC, silt curtains
should isolate turbid conditions to a limited
No additional impacts are anticipated.
CONTAMINANTS
Gray/black silt and clay, contaminated
substrate (category II and HI); class
SC water (314 CMR 4,05-4.06), an
urbanized estuarine condition,
Sequestering of cy of silt should isolate
contaminants from the areal environment.
No additional impacts are anticipated.
AQUATIC ECOSYSTEM
V
Steel bulkhead, granite seawall and
sloping rip-rap supports a moderate
growth of riicus sp., Viva sp. and
Enleromorpha sp. and barnacles; small
gravel beach supports periwinkles; soft
substrates support polychaetes,
oligochaetes and nematodes; finfish
habitat is present, but appears limited
to transient use, although flounder
spawning habitat may be present.
Loss of subtidal substrates displacing existing
benthic invertebrates (polychaetes, oligochaetes
and nematodes); reduced productivity of
barnacles, mussels and algae; finfish utilization
will also be altered, and limited to periods of
tidal inundation; any flounder spawning habitat
will be lost.
Creation of 7.7 acres of clean parent material intertidaf
habitat will replace degraded intertidal and subtidal
conditions; opportunistic and pioneer species should
naturally recruit and rework new sediments; limited hard
substrates will remain; and finfish utilization will be
limited to periods of tidal inundation.
MIXING ZONE
Open water site with no existing
mixing zone, but adjacent to shore-
based discharges/CSO's.
During disposal activities, isolated with sill
curtains/barrier, a vertical mixing zone will
include the entire intertidal and subtidal water
columns within the site, and turbidity should
settle and/or slowly be diluted by tidal
circulation.
Siltalion curtains and barriers should remain and be
maintained until any turbidity plume dissipates, and poses
little to no risk to receiving waters.
CUMULATIVE EFFECTS
Benthic substrate is currently degraded
due to the on-going silling of the
harbor system, and the contaminated
point and non-point discharges.
Sequestering of cy of contaminated silta over
7.7 acres of degraded benthic habitat, and a
permanenet loss of 7.7 acres of subtidal habitat.
Creation of 7.7 acres of clean parent material intertidal
habitat will replace degraded intertidal and subtidal
conditions; opportunistic and pioneer species should
naturally recruit and bioturbate new sediments; limited
hard substrates will remain; and finfish utilization will be
limited to periods of tidal inundation.
SECONDARY EFFECTS
Site remains in an abandoned,
degraded condition; with a potential
for future development.
Creation of 7.7 acres of clean parent material
intertidal habitat will replace degraded intertidal
and subtidal conditions; opportunistic and
pioneer species should naturally recruit and
rework new sediments; limited hard substrates
will remain; and finfish utilization will be
limited to periods of tidal inundation.
Biological communities and habitats should further
improve with the on-going improvements to the Boston
Harbor System and water quality.
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TABLE 7-3 (CON'T) FACTUAL DETERMINATION: REVERE SUGAR
404(B)(l)
GUIDELINES
SUBSTRATE
WATER CIRCULATION,
FLUCTUATION- AND
SALINITY
TURBDMTY/TSS
CONTAMINANTS
AQUATIC ECOSYSTEM
MIXING ZONE
CUMULATIVE EFFECTS
SECONDARY EFFECTS
EXISTING
CONDITIONS
Contaminated tilt overlyinj clean parent mtleriil.
Circulation influenced by lidnl exchange.
Clui SB water in on urbanized eatuarine condition.
Contaminated silt overlying clean parent material.
Arenl opportunistic/pioneer benlhic community, fairly
significant transient and brood fishery, and fish run in
adjacent river habiitat.
Abandoned berthing area with no existing mixing zone.
Benthic substrate is currently degraded due to the on-
going silting of the harbor system, and the contaminated
point and non-point discharges.
Site remains in an abandoned, degraded condition; with a
potential for future development. •
SHORT-TERM
commons
Dhpkcement of 3.7 tcrei of contaminated illty
lubstrate.
Entire watenheel area loit to (Jutland.
Sheet pile bulkhead and dewatering, limited
turbidity when the bulkhead is driven.
Sequestering of 85,000 cy of contaminated silts
over 3.7 acres of degraded benlhic substrate.
Permanent loss of 3,7 acres of aquatic habitat.
Mixing zone will be limited to any temporary or
permanent dewatering outfall to the Mystic River;
any plume should be limited and rapidly dissipated.
Sequestering of 85,000 cy of contaminated silts
over 3.7 acres of degraded benthic substrate, and a
permanent loss of 3.7 acres of aquatic habitat.
Dewatering discharges.
LONG-TERM
CONDITIONS
Sequeiterinj of 85,000 cy of conUmlmted tills
over 3.7 aero of degraded benthic lubitrate.
No additional impact! are anticipated.
No additional impacts are anticipated.
No additional impacts are anticipated.
Permanent loss of 3,7 acres of aquatic habitat.
No additional impacts are anticipated.
Permanent loss of 3,7 acres of aquatic habitat.
On-going maintenance of bulkhead ing to
eliminate potential for seeps or releases of
sequestered materials.
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TABLE 7-3 (CON'T) FACTUAL DETERMINATION: SPECTACLE ISLAND CAD
404(B)(1)
GV1DEUNES
EXISTING
CONDITIONS
SHORT-TERM
CONDITIONS
LONG-TERM
CONDITIONS
SUBSTRATE
Fine sand, silt and clay; Category I (314
CMR 9.00, generally clear of
contaminants; high levels of arsenic in
both surface and deep sediments.
Capping of the disposal pit with parent
material, and final capping with on-site
borrow material should preserve existing
substrate conditions.
No additional impacts are anticipated.
WATER
CIRCULATION,
FLUCTUATION AND
SALINITY
Tidal circulation dominates with wave
heights ranging from 0.09-2.6 ft and
wave powers of 0.1-412.9 ft Ibs/sec.
Cap elevation will mimic existing
bathymetry.
No additional impacts are anticipated.
TURBIDITY/TSS
Class SB water (314 CMR 4.05-4.06),
influenced by raw sewage discharges,
CSO's, various industrial discharges, and
urban runoff.
£ 700 mg/l @ surface for up to 600 m,
1,100 mg/l @ bottom for up to 1000 m
(LaSalle etal 1991); any plume should
rapidly dissipate.
Should return to Class SB water.
CONTAMINANTS
Fine sand, silt and clay; Category I (314
CMR 9.00, generally clear of
contaminants; high levels of arsenic in
both surface and deep sediments.
Capping of the disposal pit with parent
material, and final capping with on-site
borrow material should preserve existing
substrate conditions.
No additional impacts are anticipated.
AQUATIC
ECOSYSTEM
Benthic resources are dominated by
amphipods, gastropods and nereid
worms; EPB lobsters; and forage and
predator finfish species.
After construction/and disposal activities,
opportunistic/pioneer benthic resources
should recolonize the site.
Benthic resources should continue to be
dominated by amphipods, gastropods and
nereid worms; EPB lobsters; and forage and
predator finfish species.
MIXING ZONE
Open water site with no existing mixing
zone.
During disposal activities, isolated with silt
curtains/barriers, a vertical mixing zone
will include the water column overlying the
pit; localized and temporary turbidity
events should dissipate rapidly.
No additional impacts are anticipated.
CUMULATIVE
EFFECTS
The area has been affected by the historic
Spectacle Island Landfill; however, this
condition should be improving based on
CA/T capping and securing of the island.
No impacts are anticipated.
No additional impacts are anticipated.
SECONDARY
EFFECTS
Benthic resources are dominated by
amphipods, gastropods and nereid
worms; EPB lobsters; and forage and
predator finfish species.
Benthic resources should continue to be
dominated by amphipods, gastropods and
nereid worms; EPB lobsters; and forage
and predator finfish species.
Biological communities and habitats should
further improve with the on-going
improvements to the Boston Harbor System
and water quality.
-------
-------
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-------
Chapter Eight: Draft Section 61 Findings
This chapter of the FEIR/S'presents draft
Section 61 Findings as required by
M.G.L. c. 30 § 61. The MEPA
regulations (301 CMR 11.01 (3)) require
review and evaluation of projects to
determine whether all feasible means and
measures will be used to avoid or
minimize damage to the environment. The
draft evaluation required by M.G.L. c. 30
§ 61 can be contained in the EIR and the
required findings should be based on the
EIR. No agency may act on a permit or
commence a project until this finding is
complete.
This chapter contains a Draft Section 61
finding to comply with Massport's
responsibilities as the project's local
sponsor. A final finding will be prepared
by Massport after two key events occur.
These are:
• The Secretary issues a certificate
on the FEIR/S, and
\
• The results of a second and final
confirmatory sampling round of
fisheries, benthics and lobster
resources, conducted in April/May
1995, are completed. This data
will be made part of the Final
Section 61 Finding.
As stated in 301 CMR 11.10, any agency
which acts on a project for which an EIR
has been prepared must make a finding.
This requires DEP to prepare a Section 61
finding before it issues permits and
certifications for the BHNIP. This
Chapter therefore, also serves to provide a
draft finding that the
DEP may use as a basis for their required
finding.
Section 61 findings typically consist of the
following:
project description;
overall project impacts;
specific impacts and mitigation
measures for these impacts; and
a summary of findings.
Section 8.1 contains Massport's draft
finding and follows the outline described
above. The information presented in each
section may be repetitive with preceding
information in other sections of this
FEIR/S but is repeated as appropriate to
complete the draft finding. Section 8.2
contains a model finding for the DEP
agencies that will have permitting
responsibility for portions of the project.
8.1 DRAFT SECTION 61 FINDING
FOR MASSPORT
8.1.1 Proi ect Description
The Boston Harbor Navigation
Improvement and Berth Dredging Projects
(BHNIP) encompass the deepening of three
tributary channels (Reserved Channel,
Mystic River Channel and Chelsea Creek
Channel) and two areas in the Main Ship
Channel (Inner Confluence and the mouth
of Reserved Channel) to provide sufficient
ship maneuvering areas for the deepened
channels; six berth areas that would benefit
directly from the channel deepening
(Conley 11-13, Prolerized, Distrigas,
Moran, Eastern Minerals and Gulf Oil);
8-1
-------
and six berth areas and one intake
structure that would not benefit directly
from (i.e., be connected to) the channel
deepening (Boston Army, Boston Edison
Intake, Boston Edison Barge, Conley 14-
15, Revere Sugar, Mystic Piers 1,2,49
and 50). The President Roads Anchorage
Area and adjacent channels would be re-
marked to enlarge the deep water
anchorage without additional dredging.
Deepening of the channels to -40 ft MLW
(except Chelsea Channel to -38 ft MLW)
would allow greater use of the hitherto
underutilized -40 ft MLW Entrance
Channel and Main Ship Channel (see
Figure ES-1).
The improvements to the three Federal
channels were proposed as a result of a
Feasibility Study completed by the Corps
of Engineers in 1988. The three-channel
project was selected as the economically
and environmentally preferred project
alternative. It was authorized by Congress
in the Water Resources Development Act
of 1990 (P.L. 101-640). The authorized
project would allow the Port of Boston to
maintain its competitiveness in the highly
competitive national and international
marine trade business by reducing the cost
of transporting goods and thus improving
efficiency.
Massachusetts Port Authority (Massport),
as local sponsor of the project, submitted
an Environmental Notification Form
(ENF) to Massachusetts Executive Office
of Environmental Affairs in April 1991.
The Secretary's Certificate on the ENF
required the preparation of an
Environmental Impact Report (EIR) with
three major areas of focus:
• sediment characterization,
• evaluation of disposal alterna
tives, and
• a dredging management plan.
The Corps of Engineers, New England
Division, committed to preparing an EIS in
1992 due to the cumulative impacts of
Federal actions (maintenance dredging,
navigation improvement dredging, and
permitting of the associated berthing areas)
and the significant public concern over
disposal of dredged material. Because the
channel improvement and berth dredging
projects are intricately linked and
interdependent and would be reviewed by
the same regulatory audience, it was
determined that preparation of a joint
Environmental Impact Report/Statement
(EIR/S) would be most efficient.
A Draft EIR/S was published in April
1994. The FEIR/S responded to
comments received on the Draft including
the Secretary's certificate dated June 10,
1994 and complied with the requirements
for an FEIR as described in 301 CMR
11.07 (10). The document also met the
requirements for an FEIS as specified in
40 CFR Part 1503.
The purpose of the BHNIP is to increase
the navigational efficiency and safety of
Boston Harbor for present types of deep
draft vessels. This purpose was the basis
for the 1988 Feasibility Report prepared
by the Corps to conclude that the project
was justified economically. There are also
direct economic benefits that accrue to the
Port from the BHNIP. These include: 1)
increased navigational efficiency and safety
by reducing the need to wait out tides or to
decrease loads prior to entering the
Harbor; 2) the ability to ship more tons of
containerized cargo with fewer ships; 3)
the ability to attract new shipping lines;
8-2
-------
and 4) ability to maintain vital refined oil
products facilities and allow for double-
hulled tankers.
The BHNIP will result in removal of
approximately 1.1 million cubic yards (cy)
of silt (as measured in-place). The total
quantity of silt requiring disposal is
slightly higher, 1.4 million cy, which
accounts for 0.5 feet of over-dredging into
the underlying parent material and a 20%
expansion factor due to dredging. An
extensive sediment sampling and testing
program was undertaken to characterize
the dredged material. The surficial silt
layer (or "maintenance" material) was
found to contain varying concentrations of
metals, polynuclear aromatic hydrocarbons
(PAHs), polychlorinated biphenyls (PCBs),
and other organics. The sediment bulk
chemistry data, in combination with test
organism toxicity and bioaccumulation
testing, indicated that the silt was generally
unsuitable for unconfined open water
disposal. The complete chemical and
bioassary results are provided in Appendix
C of the Draft EIR/S.
It was further determined that the
underlying sediment (parent material) was
composed of clay and sand/gravel and has
low levels of metals and organics. The
Corps initially determined that
approximately 360,000 cy of silt was
suitable for ocean disposal. Using the
same data, however, the EPA determined
that none of the silt was suitable for
unconfined ocean disposal. In response,
the Corps adopted the more conservative
position and assumed that all silt from the
project is considered unsuitable for
unconfined ocean disposal.
The underlying parent material, composed
primarily of Boston Blue Clay with gravel
pockets, has been shown on this and other
projects to be uncontaminated and suitable
for unconfined open water disposal. The
total volume of approximately 2 million cy
of parent material (including the expansion
factor) can be disposed at an unconfined
open water site if no beneficial uses (e.g.,
landfill and/or capping) are identified.
The final component of the dredged
material is rock that would be removed
from Mystic River Channel and two areas
of the Main Ship Channel. Beneficial uses
considered for the 132,000 cy (post-
dredging volume) of rock included habitat
enhancement or armoring disposal sites
that are subject to high-energy
hydrodynamics.
In addition to addressing the dredged
material disposal needs for the BHNIP
itself, disposition of the future maintenance
of the deepened channels over the 50 year
project life was addressed. The estimated
4.4 million cy of future maintenance
material would be composed primarily of
silt. For the purpose of the disposal
alternatives analysis, it has been assumed
that this material could contain elevated
levels of contaminants. Under this
assumption (which may or may not be the
case), the material would have to be
deposited in a confined disposal site yet to
be determined. The BHNIP will not
require federal maintenance dredging for
an estimated ten years. The Corps has
responsibility for maintenance dredging.
An environmental and practicability
evaluation of options led to the
identification of the in-channel disposal
option as the least environmentally
damaging and practicable alternative.
Chapter Four of the FEIR/S provided the
environmental and practicability screening
of 24 potential disposal sites. The in-
channel option combines three sites within
the Harbor. This option disposes of silt
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within the dredging footprint of the Mystic
and Chelsea Rivers and the Inner
Confluence hi cells constructed in the
parent material that are capped with sand
after filling. The in-channel option
confines most impacts to the dredging
footprint, and is rated the least
environmentally damaging practicable
alternative (LEDPA).
The FEIR/S also identified a secondary
preferred alternative site for excess silt
capacity should the preferred alternative
fail to provide sufficient capacity after the
project is underway. Based on the
environmental and practicability screening
process mentioned above, the Little Mystic
Channel was identified as a secondary
contingency site. This site would be filled
to mean low water, changing
approximately 15 acres from a subtidal,
but degraded condition, to intertidal habitat
with clean substrate. This option provides
approximately 373,000 cy of contingency
capacity. If this site is required for
secondary capacity, mitigation for change
in substrate will be discussed with the
appropriate resource agencies when
required.
8.1.2 Summary of Project Impacts
Certain short-term adverse effects of the
dredging and in-channel disposal would be
unavoidable. Some benthic organisms and
demersal fish would be killed during
dredging and blasting. Substrate in the
areas dredged would be temporarily devoid
of benthic organisms but would be
recolonized in approximately one year,
reforming habitat with prey suitable for fin
fish. Turbidity would increase temporarily
in the area of the dredge. Use of an
environmental (closed) bucket will help
minimize contaminant release. Other
turbidity controls, such as silt curtains,
will be assessed in terms of suitability
depending on the location of the dredging
operation. Close monitoring of the
dredging operations, to identify problems
and quickly seek corrective measures, will
be undertaken.
The anticipated dredging rate would
generate approximately two to four barges
per day, depending on whether one or two
dredges were operating and the size of the
barges. Thus barge traffic should not
noticeably impede normal ship traffic.
Interference with navigation would be
minimized by coordination with the Coast
Guard.
Impacts due to disposal of dredged
materials are temporary since they do not
permanently alter the substrate of the in-
channel areas. Also, in-channel disposal
impacts remain within the footprint of the
dredging so that resource areas outside the
navigation channels are not impacted
except for temporary turbidity impacts.
During the 1 ¥2 year dredging process non-
motile benthic organisms utilizing the
disposal areas would be buried.
Recolonization should occur within one
year after disposal operations are
completed based on the existing benthic
population of early successional stage
organisms. Fin fish would tend to avoid
the area during disposal due to noise and
turbidity disturbances. The benthos and
fish would eventually recolonize the
dredge site arid will benefit from the
removal of contaminated silts. Important
anadromous fish populations would be
protected by suspending dredging and
disposal in the Mystic River during the
running season.
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The water column in the vicinity of the
disposal site would experience increased
turbidity following each disposal event.
Approximately three to five percent of the
silt/clay fraction would be lost to the
environment during the disposal descent
phase. Disposal simulation model
evaluations indicated that disposal will not
cause adverse exposure (i.e., exceedances
of water quality criteria). Based on Total
Suspended Solids (TSS), a turbidity plume
has been calculated based on fate and
transport modeling. It will not interfere
with fish passage and migration. Use of
mitigation measures, such as silt curtains,
to contain suspended solids and associated
chemicals, are proposed as additional
safeguards to minimize water quality
impacts in the Harbor.
Secondary impacts of the project,
consisting of land-side infrastructure
impacts, Harbor traffic, and other
socioeconomic interests, are minimal. The
BHNIP is not expected to increase vessel
traffic in the Harbor but will enhance
navigational safety and maintain the
competitiveness of the existing Port.
Vessel traffic will continue to include a
mix of large container ships, barges and
tankers. The Seaport Access system,
which is part of the Central Artery/Tunnel
project, will result in more direct and
convenient connections for trucks between
port terminals and the regional highway
network, thereby reducing traffic impacts
on local neighborhoods. This roadway
system is independent of the dredging
project.
8.1.3 Specific Impacts and Mitigation
Measures
Chapter Six of the FEIR/S provides a
thorough description of the primary,
secondary and cumulative impacts of the
proposed project and the specific
mitigation measures provided to minimize
the impacts. The following subsections
discuss each of the major impacts
identified in the FEIR/S and the applicable
mitigation proposed.
8.1.3.1 Impacts to Harbor Bottom
Dredging of the BHNIP will remove
contaminated silt from approximately 320
acres of Harbor bottom. Disposal of the
silt material will consist of placing the
material in 54 cells excavated into the
uncontaminated parent material. These
cells occupy approximately 116 acres
within the 320 acres impacted by dredging.
The disposal cells will be capped by clean
granular material to provide a substrate for
re-establishment of the benthic population
temporarily displaced by the dredging and
disposal. Removal of contaminated silt
and replacement of contaminated silts with
clean substrate mitigates the impacts to the
Harbor bottom.
8.1.3.2 Water Quality/Sediment Quality
Material suspended during the dredging
process is principally restricted to the silt
or clay fraction of the material with sand
particles settling out immediately after
suspension. Grain size analysis of 18
stations within the Channels identify the
substrate as 86.5% clay and silt, 11.2%
sand and 2.3% rock. Chemical oxygen
demand from the suspension of silts is
expected to be low to moderate.
Biological oxygen demand may be
temporarily impacted from increased
turbidity. Water quality modeling results
conclude that under continuous disposal at
the in-channel locations, no constituents
were found to exceed chronic water quality
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criteria if no more than 6,000 cy per day.
Modeling of an instantaneous release
scenario did not indicate any exceedance of
chronic water quality criteria.
The use of an environmental closed
bucket, and the application of silt curtains
around the disposal cells, will mitigate for
any temporary impacts to water quality
from the dredging and disposal operations.
Operational controls restricting the amount
of material disposed per day, or disposed
only at appropriate tides, will also be made
part of the dredging operational control
plans. Impacts have been determined to be
short-lived, localized and controllable
through standard dredge management
practices.
8.1.3.3 Biological Resources
The primary impact of dredging will be
the removal of benthic organisms
inhabiting the 320 acres to be dredged.
The dredging will cause a short-term loss
of benthic productivity that will be rapidly
offset through faunal recolonization
demonstrated by Boston Harbor studies.
Removal of contaminated silts over the
dredged area would improve the
maximization of faunal recovery.
Dredging could also mask chemical signals
used by migrating fish. This impact will
be avoided by scheduling dredging so as to
not coincide with migratory fish passage.
Fish and invertebrates will be impacted in
the short-term by blasting activities
proposed for small sections of the BHNIP.
Fish deterrence devices, such as sonic
blasts or bubble screens, will be deployed
to minimize fish mortality from blasting.
Disposal activities will have little or no
effect on downstream Harbor fauna since
they are characterized as tolerant to
stresses associated with fluctuating
turbidity levels and dissolved oxygen
reduction. The use of silt curtains will
minimize the downstream impacts^ if any,
on Harbor fauna.
8.1.3.4 Operational Controls,
Contingencies and Mitigation
Impacts associated with the field operations
of dredging arid disposal were described in
Chapter Five of the FEIR/S. Operational
controls and mitigation strategies have
been incorporated into the project design.
These operational controls are:
• Capping the disposal cells with
sand to maximize the potential for
faunal recolonization with rock
armoring in areas subject to vessel
prop wash scouring;
• Scheduling of dredging and
disposal to fit environmental
window and to meet water quality
criteria
• Coordinating with the U.S. Coast
Guard to avoid interference
between BHNIP activities and
commercial traffic
• Scheduling activities to avoid peak
recreational Harbor usage (4th of
July, other holidays)
• Identification of significant
structural features (bridge
abutments, utility lines, bulkheads,
moorings and buoys) to avoid
negative impacts
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Imposition of dredging
performance standards to meet
environmental and permitting
conditions as well as design
controls
Use of environmental bucket to
trap contaminated sediments during
dredging and outfitted with a
sensor to detect closure problems
due to debris
Use of silt curtains during disposal
Requirement for contractor to
provide an incident response plan
to cover spills of dredged material,
fuel and machinery oil
Trash and debris management on
separate scows with agreements to
dispose of materials in landfills
Contingency plans for reasonably
foreseeable equipment failures,
weather conditions, encounters
with buried structures, and permit
limit exceedances
resource enhancement opportunities in the
Harbor area. As examples these can
include working with state and local
resource agencies to identify potential
resource enhancement options such as
supporting the development of an "urban
fishing park" through rehabilitation of
water access structures to enhance pubic
use and access to functional recreational
fishing areas. In addition, Massport is
willing to work with appropriate agencies
to increase the number of vessel sewage
pump-out facilities in the Harbor Area.
8.1.4 Findings
For the reasons stated above, Massport
finds that, with implementation of the
operational mitigation measures described,
all practicable means and measures will be
taken to avoid or minimize adverse
impacts to the environment relative to
Massport actions. It is anticipated that
appropriate conditions will be included in
environmental permits to be issued by the
DEP to ensure implementation of said
measures.
• A recognition that the Corps will
make parent material available for
beneficial use
• A recognition that the in channel
sites will be monitored by the
Corps under the DAMOS
program.
8.1.3.5 Resource Enhancement Activities
Based on the data provided in the FEIR/S,
the preferred alternative will not require
compensatory resource mitigation. As
local sponsor, Massport is willing to work
with state resource agencies to identify
8.2 MODEL SECTION 61 FINDING
FOR DEP AGENCIES
The BHNIP project will require permits
and approvals from the following DEP
agencies:
• Massachusetts Department of
Environmental Protection
- Water Quality Certification
- Division of Wetlands and Waterways
review of local Order of Conditions
• Massachusetts Office of Coastal Zone
Management
- Coastal Zone Consistency Review
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The following paragraphs provide a
detailed outline of how the BHNIP
complies with DEP regulatory policies for
their permits.
8.2.1 Massachusetts Wetlands Protection
Act (MGL c. 131. § 40 and 310 CMR
lo.om
The entire aquatic portion of the BHNIP
will occur within the Mystic River,
Chelsea Creek, East Boston and South
Boston DPA's and as such, must address
only one significant resource (land under
ocean) relative to the Act and Regulations.
This limits protectable interests to storm
damage prevention and flood control, and
the protection of marine fisheries. To
comply with these interests, the BHNIP
must fulfill specific applicable performance
standards. The BHNTP fulfills these
requisite conditions hi the following
manner:
1) Dredge channel and port area so that
all portions of them will be adequately
flushed by the tides.
BHNIP Compliance:
The proposed channel deepening should
not alter the flushing rate of Boston
Harbor appreciably, given the 150 billion
gallon plus diurnal tidal prism that
currently exists.
2) Complete the dredging operation as
quickly as possible by using the most
efficient and practical equipment.
BHNIP Compliance:
The proposed navigation improvement
dredging is scheduled to occur over a 12
to 18-month time frame. Mechanical
Dredging with limited blasting has been
selected as the most feasible method to
complete the BHNIP. An environmental
bucket, determined to be the most feasible
and least environmentally damaging
methodology to dredge contaminated
material, will be used to remove the silts.
3) Where possible, schedule dredging so
as not to conflict with fisheries use.
BHNIP Compliance:
As required by regulation, the BHNIP will
avoid any construction or disposal activity
during the period of March 15 through
June 15. In addition, the turbidity plume
for the in-channel locations does not
impede fish passage in any of the Channels
4) Bottom sediment analysis and
evaluation of dredging should be
coordinated with the DWPC.
BHNIP Compliance:
As stated in the DEIR/S, and based on the
3 tier analyses, the 2.9 million cubic yards
of dredged material from the BHNIP will
consist of approximately 1.7 million cubic
yards of "clean" parent material including
rock. The remaining 1.1 million cubic
yards of silty material has been determined
to be contaminated. Therefore, the
BHNIP accepts the finding that all of the
silt material is considered to be unsuitable
for unconfined open water disposal.
Further, all bulk chemistry, bioassay and
biological evaluations have been planned
and coordinated with federal and state
regulatory authorities. Extensive water
quality modeling studies have been
performed for the in-channel options.
Results indicate that the option meets
DWPC regulations.
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5) Minimize the amount of dredging.
BHNIP Compliance:
The Full Project is the preferred, and
congressionally-authorized alternative for
the dredging project. In addition to the
removal of all unconsolidated silts required
for maintenance, parent material would be
dredged to project depths. The purpose
and need for the Full Project has been
documented in the FEIR/S. It offers the
greatest benefits to the Port of Boston.
The impacts associated with the dredging
are temporary. In the absence of
improvement dredging, maintenance
dredging of the channels and berths would
be required to maintain navigational safety.
The maintenance material, or silt, is the
contaminated portion of the BHNIP
dredged materials. Issues regarding silt
dredging and disposal, are therefore, issues
that require resolution regardless of the
improvement project.
6) Whenever possible, channel axis
should not be parallel to direction of
major storm waves.
BHNIP Compliance:
The BHNIP is limited to the existing
channel configuration.
7) Wave height at any point along the
shoreline shall not increase by more than
10% by disposal of dredged material on
nearshore areas of land under ocean.
BHNIP Compliance:
The BHNIP will not significantly alter
surface water hydrology within the project
area.
8) Dispose of spoil in discontinuous
bands, interrupted at least every 250 ft.
by 50 ft. breaks to provide for passage
of water, nutrients and aquatic life.
BHNIP Compliance:
This does not apply to the BHNIP since
disposal of the silt materials will occur and
be sequestered within the in-channel cells.
9) Dredged material disposal on any
portion of land under the ocean shall
have a mean grain size distribution
which does not differ from the existing
land under the ocean sediment grain size
by more than 50%.
BHNIP Compliance:
No dredge material disposal will occur on
any unpermitted or undesignated land
under the ocean. In-channel disposal will
be fully contained, sequestered and capped
beneath granular substrate material.
10) Disposal of dredged material should
avoid eel grass beds to the maximum
extent possible.
BHNIP Compliance:
There are no eelgrass beds located at the
in-channel sites.
11) Sedimentation or catch basins as
appropriate to the amount of runoff.
BHNIP Compliance:
Not applicable to the BHNIP project.
12) AH drainage structures should have
gas traps, with appropriate
maintenance.
8-9
vi/9
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BHNIP Compliance:
Not applicable to the BHNIP project.
13) Headwall and supports must be
spaced so that sediment transport is not
interrupted.
BHNIP Compliance:
Not applicable to the BHNIP project.
14) Space piles as far apart as practical
for the structures being built, in no case
less than 10 feet apart.
BHNIP Compliance:
Not applicable to the BHNIP project.
15) Construction shall be completed as
quickly as possible to minimize the
amount of turbidity and sedimentation.
BHNIP Compliance:
The BHNIP should be completed over a
12-18 month timeframe with dredging and
disposal within the same footprint so that
minimal additional areas would experience
turbidity and sedimentation impacts.
8.2.2 Massachusetts Waterways Licensing
Program (MGL c. 91 and 310 CMR 9.00)
While Massport is exempt from the
requirement of an individual license,
individual private berth owners are not.
The BHNIP complies with c. 91
performance standards in the following
manner:
1) Unless the project is located in a
DPA, no dredging of channels, mooring
basin, or turnarounds should occur
below a mean low water depth of 20 ft.
unless the waterway serves a commercial
navigational purpose of jurisdictional
significance and cannot be relocated to a
DPA.
BHNIP Compliance:
The entire dredging and dredged material
disposal program is situated in the Mystic
River, Chelsea Creek, East Boston, or
South Boston DPA's.
2) The design and timing of dredged
material disposal activity shall be such
as to avoid interference with
anadromous/catadromous fish runs. At
a minimum, no such activity shall occur
in such areas between March 15th and
June 15th of any year, except upon a
determination by the Division of Marine
Fisheries (MADMF) that such an activity
will not obstruct or hinder passage of
fish.
BHNIP Compliance:
The BHNIP avoids any
construction/disposal activities during the
period of March 15 through June 15.
3) The design and timing of dredging
and dredged material disposal activity
shall be such as to minimize adverse
impacts on shellfish beds, fishery
resource areas, and submerged aquatic
vegetation.
BHNIP Compliance:
Given the nature of the current water and
sediment quality of the project area, the
opportunistic character of the benthic
biota, and the lack of aquatic vegetation;
the BHNIP does not permanently impact
any of these biological resources. Any
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disturbance or displacement will be
temporary, and the sediment quality of the
post dredge substrate will be clean
granular material.
4) Outline operational requirements for
dredging and dredge material disposal,
for review and approval.
BHNIP Compliance:
Chapter Five of the FEIR/S provided a
comprehensive Dredge Management Plan
outlining all proposed operational
requirements that satisfy this performance
standard.
5) Provide appropriate supervision of
dredging and dredge material disposal.
BHNIP Compliance:
Chapter Five of the FEIR/S provided a
comprehensive Dredge Management Plan,
and details all proposed supervision and
construction management plans sufficiently
to meet this performance standard.
8.2.3 MCZM Policies Applicable to the
BHNIP
1) Policy 1 states, "Protect ecologically
significant resource areas (salt marshes,
shellfish beds, dunes, beaches, barrier
beaches and saltponds) for their
contribution to maritime productivity
and value as natural habitats and storm
buffers."
BHNIP Compliance:
The BHNIP dredging and disposal plans
will not impact resources identified in this
policy.
2) Policy 4 states, "Condition
construction in water bodies and
contiguous land areas to minimize
interference with water circulation and
sediment transport and to preserve
water quality and marine
productivity..."
BHNIP Compliance:
Dredging and material disposal activities
should have minimal temporary effect on
water quality, marine productivity, and the
designated fish runs. Appropriate
scheduling of activities during periods of
low productivity and environmental
dormancy should serve to minimize
adverse effects to biological resources.
The in-channel disposal and sequestering
of contaminated silts, and the disposal of
clean parent material at designated and
approved disposal sites, should help to
balance both water and sediment quality.
Also, biological resources will naturally
re-establish themselves in the post project
condition. Re-colonization is expected
after one year following disposal.
3) Policy 5 states, "Ensure that
dredging and disposal of dredged
material minimizes adverse effects on
water quality, physical processes, marine
productivity and public health".
BHNIP Compliance:
Since the channel bathymetry will not be
significantly lowered in the post dredging
condition, there should also be no increase
in flood erosion hazards or adverse effects
on natural replenishment of beaches.
Given the nature of the project area
shoreline, sediment transport is not very
significant within the project area.
Turbidity will be a short-term
phenomenon, and should pose no long
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lasting adverse effects. Contaminant
stripping during dredge and dredge
material disposal should be controllable.
No chronic water quality thresholds will be
exceeded during either continuous or
instantaneous loadings, provided daily
disposal volumes do not exceed 6,000
cy/day.
4) Policy 7 states, "Encourage the
location of maritime commerce and
development in segments of urban
waterfronts designated as port areas.
Within these areas, prevent the exclusion
of maritime dependent industrial uses
that require the use of lands subject to
tidelands licenses."
BHNIP Compliance:
All facets of the dredging and dredge
material disposal proposal are consistent
with the DPA designation and consistent
with existing usage. The deepening of the
channel is necessary to make the DPA
serviceable to the current shipping needs.
5) Non-Regulatory Policy 7, which deals
with state financial assistance and direct
state action states, "Encourage through
technical and financial assistance
expansion of water-dependent uses in
DPA's and developed harbors,
redevelopment of urban waterfronts and
expansion of visual access".
BHNIP Compliance:
The proposed maintenance and
improvement dredging is consistent with
this policy.
8.2.4 Section 401 Water Quality
Certification
The BHNIP must demonstrate that it
complies with the 404(b)(l) guidelines (40
CFR 230.11) and 310 CMR 9.00
regulations for water quality certification.
The following narrative demonstrates the
BHNIP's compliance with these guidelines.
1) Physical Substrate Determination
BHNIP Compliance:
The BHNIP will remove both
contaminated silt, clean parent material
(clay), and/or rock from 320 acres
federally designated channels and berthing
areas exposing clean parent material
(predominately clay with some ledge)
throughout the project area. The resultant
substrate should be clean and
representative of the natural harbor
substrate. Existing silts appear to be the
result of continuous point and non point
discharge to the Boston Harbor
Environment.
In-channel disposal of the contaminated silt
material will provide in-situ disposal
opportunity of dredge material. The
capping of the in-channel cells with the
BHNIP parent material and/or sand would
also provide suitable clean post-project
benthic substrate. The disposal and
sequestering of the silt material within the
in-channel cells should provide an overall
improvement in substrate conditions.
2) Water Circulation, Fluctuation and
Salinity Determination
BHNIP Compliance:
The channel deepening and proposed
dredge material disposal program will not
alter the existing hydrology, flushing rate
tidal prism.
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3) Suspended Particulate/Turbidity
Determination
BHNIP Compliance:
The dredging of the channel and berth
areas will be performed in a manner to
minimize the possibility of sediment
release. A review of the levels of
sediment chemistry, the ambient water
quality and the use of an environmental
bucket, indicates that a low potential exists
for substantial degradation of ambient
water quality during dredging.
Several factors may affect the
characteristics of turbidity plumes
associated with the project, including the
discharge rate, character of the dredged
material slurry, water depth,
hydrodynamic regime, and the discharge
configuration. Typically, the quantity of
material re-suspended in the upper water
column ranges from 1-5% of the total
amount released.
The BHNIP modeling analysis presented in
the FEIR/S indicates that no chronic water
quality thresholds will be exceeded during
either continuous or instantaneous
loadings, provided daily disposal volumes
do not exceed 6,000 cy/day.
4) Contaminant Determination
BHNIP Compliance:
The BHNIP modeling analysis included in
the FEIR/S indicates that no chronic water
quality thresholds will be exceeded during
either continuous or instantaneous
loadings, provided daily disposal volumes
do not exceed 6,000 cy/day.
In-channel disposal, as proposed,
concentrates both dredging and material
disposal operations within the BHNIP
footprint. This will minimize the project
area and impacts involving additional
remote sites.
5) Aquatic Ecosystem and Organic
Determinations
BHNIP Compliance:
The Harbor benthic fauna! communities
are dominated by opportunistic deposit
feeders. The Harbor is inherently stressful
to benthic populations due to low DO
levels and sediment contamination. The
removal of this assemblage of organisms
during dredging will have minimal impact
on the ecological productivity of the
Harbor as a system.
The dredging of the channel will cause a
short term loss of benthic productivity that
will be rapidly offset through faunal
recolonization. Fishery resources
associated with the Mystic River, Chelsea
Creek and Inner Confluence are
moderately significant based on a fisheries
survey reported in the FEIR/S as Appendix
E.
The Mystic River catch was dominated by
winter flounder, atlantic tomcod and scup.
The Chelsea River catch was also
dominated by winter flounder and atlantic
tomcod. At the Inner Confluence, the
dominant catch species was winter
flounder. These findings are comparable
with previous finfish surveys in the area.
Chemical signals essential for anadromous
fishery migrations could become masked
by the dredging operation's suspension of
sediments and associated chemicals.
Dredging will be scheduled in non-
sensitive areas of the Harbor and during
appropriate periods to avoid impacting
8-13
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seasons of critical spawning runs of those
species.
Sediment suspension will also displace
motile species that will attempt to avoid
gill abrasion, lower DO levels, and
reduced sensory opportunities for predation
(masked odors and low visibility) in the
dredging area. These would be temporary
and the effects would not have long-term
detrimental impacts given the
recommended mitigation practices.
Downdrift harbor fauna should be tolerant
to stresses associated with fluctuating
turbidity levels and DO reduction.
Locating the material disposal locations
within the dredging footprint limits stresses
associated with the BHNIP from being
exerted on remote communities. Most of
the episodic effects on all biological
resources will be triggered by the dredging
itself. Motile organisms should evacuate
the sites before and after filling or habitat
displacement takes place. Sessile
organisms will be lost.
Species of marine mammals which may
occur in tidal waters hi the vicinity of the
project area, include harbor seals (Phoca
vitulina), harbor porpoises (Phocena
phocena), and grampuses (Grampus
griseus). However, their presence in the
Boston Harbor system is uncommon.
Since most of the dredging impacts will
occur well within the Inner Harbor where
marine mammals are uncommon, the
project will not cause adverse impacts to
these species.
The intertidal and subtidal areas, including
and adjacent to the Federal channel area,
are not known to provide habitat for any
Federal threatened and/or endangered
species, or State rare species. Letters
from the U.S. Fish and Wildlife Service,
the National Marine Fisheries Service and
the State Natural Heritage Program have
confirmed the lack of any threatened,
endangered, or rare species in the area.
6) Disposal Site Determinations (Mixing
Zone)
BHNIP Compliance:
For the in-channel site, the mixing zone
will extend over several acres. Based on
hydrographic variations, the following
spacial extents were reported in the
FEIR/S:
Mystic River: 12.4 acres
Chelsea Creek: 30.0 acres
Inner Confluence: 14.7 acres
Data reported in the FEIR/S and technical
appendices indicate the mixing zone will
not impact or impede fishery migration.
8.2.5 Findings
For the reasons stated above, the DEP
finds that, with the implementation of the
operational mitigation measures decribed,
all practicable means and measures will be
taken to avoid or minimize adverse
impacts to the environment. It is
anticipated that appropriate conditions will
be included in DEP permits to ensure
implementation of said measures.
8-14
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-------
Chapter Nine : Literature Cited
Averett, Daniel E., et. al. 1990. Review of removal, containment and treatment
technologies for remediation of contaminated sediment in the Great Lakes. Prepared by
USAGE Waterways Experiment Station for USEPA, December, 1990.
Cortell, J. M. and Associates, Inc. 1990. Aquatic resource functions and values. Vol. 2:
Disposal sites alternatives assessment. Central Artery (I-93)/Tunnel (1-90) Project.
Prepared for the Massachusetts Highway Department.
Environmental Protection Agency/Corps of Engineers (EPA/ACOE). 1991. Evaluation
of Dredged Material Proposed for Ocean Disposal, Testing Manual. EPA-50318-
91/001.
Gross, M. <3rant. 1977. Oceanography, 2d Ed.
Haedrich, ILL. and S.O- Haedrich. 1974. A Seasonal Survey of the Fishes in the Mystic
River, a Polluted Estuary in Downtown Boston, MA. Est. Coast. Mar. Sci. 2:59-73.
LaSalle, Mark W., Clarke, Douglas G., Homziak, Jurij, Lunz, John D., and Fredette,
Thomas J. 1991. A Framework for Assessing the Need for Seasonal Restrictions on
Dredging and Disposal Operations," Technical Report D-91-1, U.S. Army Engineer
Waterways Experiment Station, Vicksburg, MS.
Massachusetts Port Authority (Massport) and U.S. Army Corps of Engineers. 1994.
Draft Environmental Impact Report/Study for the Boston Harbor Navigation
Improvement and Berth Dredging Projects, 2 Volumes.
Normandeau Engineers, Inc. 1989. An independent assessment of the selection process
for MWRA residuals landfill hi the greater Boston area, prepared for the City of
Revere, Massachusetts. 24 pp. + App.
Rhoads, D.C. and J.D. Germano. 1982. Characterization of organism-sediment relations
using sediment profile imaging: an efficient method of remote ecological monitoring of
the seafloor (REMOTS system). Mar. Ecol. Prog. Ser. 8:115-128.
9-1
-------
U.S. Army Coips of Engineers (ACOE-NED), New England Division. 1988. Feasibility
report and environmental assessment for deep-draft navigation improvements to Boston
Harbor including Mystic River, Chelsea River and Reserved Channel.
U.S. Environmental Protection Agency (EPA). 1990. Public record of decision on the
Final Supplemental Environmental Impact Statement, Long Term Residuals
Management for Metropolitan Boston.
U.S. Environmental Protection Agency (EPA). 1989. Draft Environmental Impact
Statement for the Designation of the Massachusetts Bay Disposal Site.
9-2
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CAPPING BIBLIOGRAPHY
Allard, Y. 1987. Capping operation at Georgetown, Prince Edward
Island. Proceedings: 4th Ocean Dumping Control Research Fund,
Atlantic Region Workshop (1985/86 & 1986/87). Halifax, N.S.,
24-25 February, 1987. Surveillance Report EP-5-AR-87-7.
Bajek, ' J..-, R. W. Morton, J. D. Germano and T. .J. .Fredette. 1987.
Dredged material behavior at a deep water open ocean disposal
site. Proceedings of the Twentieth Dredging Seminar. Western
Dredging Association Annual Meeting, Toronto, Canada.
September, 1987, pp. 95-107.
Bokuniewicz, H. 1985. Behavior of sand caps on subaqueous
dredged-sediment disposal sites.
Bokuniewicz, H. 1989. Behavior of sand caps on subaqueous
dredged-sediment disposal sites. In, Oceanic Processes in
Marine Pollution, Vol. 4. Scientific Monitoring Strategies
for Ocean Waste Disposal, D. W. Hood, A. Schoener, and P. K.
Park, eds, Krieger Publishing Co., Malabar, FL.
Bokuniewicz, H., R. Cerrato, and A. Mitchell. 1981. Criteria
for caps on subaqueous disposal sites. In: Proceedings,
Dredging and Related Problems in the Mid-Atlantic Region.
Conference held Oct. 5, 6, & 7, 1981. Maryland NAEP & WEDA,
East. pp. 1-7.
Bokuniewicz, H. J., J. Gebert, R. B. Gordon, J. L. Higgins, P.
Kaminsky, C. C. Pilbeam, M. Reed, and C. Tuttle. 1978. Field
study of the mechanics of the placement of dredged material at
open-water disposal sites. Volume II: Appendices J-O.
Dredged Material Research Program. Tech. Rept. D-78-7. US
Army Corps of Engineers Waterways Experiment Station,
Vicksburg, MS.
Bokuniewicz, .H. J., and R. B. Gordon. 1979. Containment of
particulate wastes at open-water disposal sites. In: Ocean
Dumping and Marine Pollution, H. D. Palmer and M. G. Gross.
Dowden, Hutchinson & Ross, Inc. Shroudsbury, PA. pp. 109-
129. . .
Bokuniewicz, H. J. and R. B. Gordon. 1980. Deposition of dredged
sediment at open water sites. Est. Coast. Mar. Sci. 10, 289-
303.
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-------
Brandes, H., A. Silva, and T. Fredette. 1991. Settlement of
offshore mounds of capped dredged materials. Maritimes 35 (J),
12-14. ' ' . '
Brannon, J. M., R. E. Hoeppel and D. Gunnison. 1984. Efficiency
of capping contaminated dredged material. In, Dredging and
Dredged Material Disposal, Vol. 2 (R. L. Montgomery and J. W.
Leach, Editors). Proceedings of a Conference Dredging 84,
Clearwater Beach, FL. ASCE. pp. 664-673.
Brannon, J. M., Hoeppel, R. E., Smith, I. Jr.,. and Gunnison,. D.
Long-Term Effectiveness of Capping in Isolating Dutch Kills
Sediment from Biota and the Overlying Water. August 1986,
FINAL REPORT.
Brannon, J. M., R. E., Hoeppel, T. C. Sturgis, I. Smith,_Jr., and
D Gunnison. 1985. Effectiveness of capping in isolating
contaminated dredged material from biota and the overlying
water. Technical Report D-85-10. US Army Corps of Engineers,
Waterways Experiment Station, Vicksburg, MS.
Brannon, J. M., R. E. Hoeppel, T. C. Sturgis, I. Smith, Jr., and
D.Gunnison. 1985. Effectiveness of capping in isolating
dutch kills sediment from biota and the overlying water. June
1986 FINAL REPORT.
Brannon, J. M., McFarland, Wright, and Engler. Utility of sediment
quality criteria (SQC) for the environmental assessment and
management of dredging and disposal of contaminated sediments.
Feb. 20, 1990.
Dehlinger, P., Fitzgerald, W. F., Paskansky, D. F.,. ,Garvine, R. W.,
Bohlen, W. F., Feng, S. W., Nalwalk, A. J., Szechtman, R. J.,
Hunt, C. D., Murphy, D. L., Perkins, C. E., Ruddy G. M.
Investigations on Concentrations, Distributions, and Fates of
Heavy Metal Wastes in Parts of Long Island Sound. Final
Report,-Submitted to the office of Sea Grant Programs National
Oceanic and Atmospheric Administration, Rockville, Maryland
20852.
Feng, S.Y. Damos Mussel Watch Program Monitoring of the "Capping"
Procedure Using Mytilus edulis at the CLIS Disposal Site.
1982, contribution #22.
Fredette, T. J. In Prep. A summary of recent capping
• investigations with dredged materials in New England, USA.
Proceedings of the Fifteenth United States/Japan Experts
Meeting on Management of Bottom Sediments Containing Toxic
Substances". San Pedro, CA, 19-21 November 1991.
Capping Bibliography
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-------
Fredette, T.J., W.F. Bohlen, B.C. Rhoads and R.W. Morton. 1989.
Erosion and Resuspension Effects of Hurricane Gloria at Long
Island Sound Dredged Material Disposal Sites. Environmental
Effects of Dredging, Information Exchange Bulletin, Vol.
D-89-2, US Army Corps of Engineers Waterways Experiment
Station, Vicksburg, MS.
Fredette, T. J., J. D. Germano, P. G. Kullberg, D. A. Carey, and P.
Murray. 1992. Chemical stability of capped dredged material
disposal mounds in Long Island Sound, USA. Chem. Ecol. 7:173-
194.
Fredette,"T. J, P. G. Kullberg, D. A. Carey, R. W. Morton, and J.
D. Germano. 1992. Twenty-five years of dredged material
disposal site monitoring in Long Island Sound:. A long-term
perspective. Proceedings of the Long Island Sound Research
Conference, New Haven/-"Connecticut.
Fredette, T. J., R. W. Morton, W. F. Bohlen and D. C. Rhoads.
1988. Erosion and resuspension effects of Hurricane Gloria at
Long Island Sound dredged material disposal sites. Corps of
Engineers Seventh Seminar on Water Quality, Charleston, NC,
February, 1988. ' • • .
Freeland, G. L., R. A. Young, G. Drapeau, T. L. Clarke, and B. L.
Benggio. 1983. Sediment cap stability study: New York
dredged material dumpsite. Prepared for the U. S. Army Corps
of Engineers, New York District and the Office of Marine
Pollution Assessment, NOAA. Final Report under Agreement No.
NYD 80-124(C).
Gordon, R. B. 1974. Dispersion of dredge spoil dumped in near-
shore waters. Est. Coast. Mar. Sci 2,349-358.
Gunnison, D., J. M. Brannon, T. C. Sturgis and I. Smith, Jr. 1987.
Development of a simplified column test for evaluation of
thickness of capping material required to isolate contaminated
dredged material. Miscellaneous Paper D-87-2. US Army Corps
of Engineers, Waterways Experiment Station, Vicksburg, MS.
Kahn, A., and. J. Grossi. 1984. Confined disposal in the Canadian
Great Lakes. In: -Proceedings, Dredging and Dredged Material
Disposal, Vol. II, R. L. Montgomery and J. W. Leach, eds.,
Conference held at Clearwater Beach, Fla., Nov. 14-16. ASCE,
NY, NY, pp. 654-663.
Kullberg, .P. K. and T. J. Fredette. In press. Management of
dredged material capping projects: An example from New
EngjLand. Proceedings of the First International Specialized
Conference on Contaminated .Sediments: Historical Records,
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r
Environmental Impact, and Remediation, June 14-16 1993,
Milwaukee, Wisconsin.
Morton, R. W. 1980. The management and monitoring of dredge spoil
disposal & capping procedures in Central Long Island Sound.
2nd International Ocean Dumping Symposium, Woods Hole, Mass.
DAMOS Contribution #8. U. S. Army Corps of Engineers, New
England Division, Waltham, MA..
Morton, R. W. 1983. Precision bathymetric study of dredged
material capping experiment in Long Island Sound. In: Wastes
in the Ocean. Vol 2. (eds) Kester et al. John Wiley and Sons,.
New York! pp. 99-121.
Morton, R. W. 1987. Recent Studies Concerning the Capping of
;1>Contaminated Dredged Material: United States/Japan Experts
Meeting on Management of Bottom Sediments Containing Toxic
Substances. November 3-6, 1987. Baltimore MD
Morton, R. W. 1988. Monitoring the effectiveness of capping for
isolating contaminated sediments. In: Contaminated Marine
Sediments - Assessment and Remediation. National Academy
Press, Washington, D.C., pp. 262-279.
Morton, R. W., Andreliunas, Crawford, J. P., Congdon. Integration
of Management and Monitering of Dredged Material Disposal in
New England Waters.
Morton, R. W. and M. -C. Miller. 1980. Stamford-New Haven disposal
operation monitoring survey report. DAMOS Contribution #7.
U. S. Army Corps of Engineers, New England Division, Waltham,
MA.
Morton, R. W. and M. R. Palermo. 1989. Development of procedures
to manage and monitor 'capping1 of contaminated dredged
material. Proceedings of the Eighth International Ocean
Disposal Symposium, 9-13 October 1989, Dubrovnik, Yugoslavia.
NED (New England Division). 1990. New Bedford Harbor Superfund
pilot study: Evaluation of dredging and dredged material
disposal.. U. S. Army Corps of Engineers, New England
Division, Waltham, MA. ,.
NUSC (Naval Underwater Systems Center). 1979a. Stamford/New Haven
disposal operation monitoring survey report - baseline
surveys. DAMOS Contribution #1. U. S. Army Corps of
Engineers, New England Division, Waltham, MA.
NUSC (Naval Underwater Systems Center). 1979b. Stamford/New Haven
disposal operation monitoring survey report - 20,000 yd
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March 28, 1994
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increment. DAMOS Contribution #2. U. S. Army Corps of
Engineers, New England Division, Waltham, MA..
NUSC (Naval Underwater Systems Center) . 1979c. Stamford/New Haven
disposal operation monitoring survey report - 50,000 southern
side, 10,000 northern side. DAMOS Contribution #3. U. S.
Army Corps of Engineers, New England Division, Waltham, MA.
NUSC (Naval Underwater Systems Center) . 1979d. Completion of
Stamford disposal (Stamford/New Haven). DAMOS Contribution
#4. U. S. Army Corps of Engineers, New .England Division,
Waltham,' MA. ' '.' ""•
NUSC (Naval Underwater Systems Center) . 1979e. Post disposal
. surveys (Stamford/New, Haven) . DAMOS Contribution #5. U. S...
Army Corps of Engineers, New England Division, Waltham, MA.
NUSC (Naval Underwater Systems Center). 1979f. .Post disposal
monitoring (Stamford/New Haven). DAMOS Contribution #6. U.
S. Army Corps of Engineers, New England Division, Waltham, MA.
NYUMC (New York University Medical Center). 1982. Identifying
chemical signatures of disposed dredged materials. Prepared
for U. S. Army Corps of Engineers, New York District under
Contract No. DACW51-80-R-0002.
O'Connor, J. M. and S. G. O'Connor. 1983... Evaluation of the 1980
capping operations at the experimental mud dump site, New York
Bight apex. Technical Report D-83-3, US Army Engineers
Waterways Experiment Station,' Vicksburg, MS.
O'Connor, J. M. and M. Moese. 1984. Distribution of'contaminants
in experimentally capped dredged material deposits. Final
Report to The Research Foundation of the State University of
New York, Albany, NY.
Palermo, M. R. 1989. Capping contaminated dredged material in
deep water. Proceedings of the Specialty Conference, Ports,
'89. ASCE. Boston, MA.
Palermo, M. R. 1991. Design requirements for capping. Dredging
Research Technical Note DRP-5-03. US Army Engineer Waterways
Experiment Station, Vicksburg, MS.
Palermo, M. R. 1991. Site selection considerations for capping.
Dredging Research Technical Note DRP-5-04. US Army Engineer
Waterways Experiment Station, Vicksburg, MS.
Palermo,^-M. R. 1991. Equipment and placement techniques for
capping. Dredging Research Technical Note DRP-5-05. US Army
Engineer Waterways Experiment Station, Vicksburg, MS.
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Palermo, M. R.",' T. J. Fredette, and R. E. Randall. 1992.
Monitoring considerations for capping. Dredging Research
Technical Note DRP-5-07. US 'Army Engineer Waterways
Experiment Station, Vicksburg, MS.
Parametrix, Inc. March 1989. Sediment Monitoring Simpson Cap
Project. 35-1650-08.
Parker, J. W. Monitoring and Management of Dredged Material
Disposal and Capping. The disposal of dredged material in
coastal waters has led to increased concern .over the potential
for contaminating the sediment and its inhabitants.
Randall, R. E. and M. R. Palermo. 1990. Demonstrations of
equipment and .techniques• for capping contaminated dredged
material. Dredging Research Information Exchange Bulletin
DRP-90-4.
Romberg, P. and A. Sumeri. 1988. Sediment capping at Denny Way
CSO. In:' Proceedings, First Annual Meeting on Pugef Sound
Research. Vol. 2, The Seattle Center, Seattle, WA, March 18-
19, 1988. Puget Sound Water Quality Authority. Seattle, WA.
pp. 697-706.
SAIC (Science Applications International Corporation). 1984.
Results of monitoring studies at Cap Sites #1, #2, and the FVP
site in Central Long Island Sound and a classification scheme
for the-management-of capping procedures. DAMOS Contribution
#38. U. S. Army Corps' of Engineers, New England Division,
Waltham, MA.
Science Applications International Corporation (SAIC). 1990.
Capping Survey at the New London Disposal Site, February 3,
1989. DAMOS Contribution #71, US Army Corps of Engineers, New
England Division, Waltham, MA.
Science Applications International Corporation (SAIC). 1990.
Monitoring Cruise at the Massachusetts Bay Disposal Site,
November 1988 -January 1989. DAMOS Contribution #73, US Army
Corps of Engineers, New England Division, Waltham, MA.
Shields, F. D. and R. L. Montgomery. 19841 Fundamentals of
capping contaminated dredged material. In, Dredging and
Dredged Material Disposal, Vol 1 (R. L. Montgomery and J. W.
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Stewart, L. L. April 21-25, 1986. Sixth International Ocean
Disposal Symposium, In-Situ Assessment of Faunal-Sediment
.Ecology at Deep (about 100 meter) New England Dredged Material
Disposal Sites.
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Sumeri, A. 1984. Capped in-water disposal of contaminated dredged
material. In, Dredging and Dredged Material Disposal, Vol 2
(R. L. Montgomery and J. W. Leach, .Editors) . Proceedings of
a Conference Dredging '84, Clearwater Beach, FL. ASCE. Pp.
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Sumeri, A. July 1989. Duwamish CAD Site. The U.S. Army Corps of
Engineers (COE) started the Duwamish River CAD site in March
1984... 14-1 7/14/89.
Sumeri, A. 1989. Confined aquatic disposal and capping of
contaminated sediments in Puget Sound.' Proceedings of the
Xllth World Dredging Congress, Western Dredging Association,
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Sumeri, A. 1991. Capping of contaminated bottom sediment in
Elliott Bay, Washington. Dredging Research Information
Exchange Bulletin "DRP-91-3.• U. S. Army Engineer Waterways
Experiment Station, Vicksburg, MS.
Sumeri, A. Duwamish Waterway Confined Aquatic Disposal (CAD) of
Contaminated Dredge Material-Five Years Later.
Sumeri, A., T. J. Fredette, P. G. Kullberg, J. D. Germano, D. A.
Carey, and P. Pechko. 1991. Sediment Chemistry Profiles in
Capped Dredged Material Disposal Deposits: Results from Three
US Army Corps of Engineer Offices. Proceedings of the Twenty-
fourth 'Annual Dredging Seminar, Las Vegas, Nevada. Pp. 161-
187. - . '
Sumeri, A. and P. Romberg. 1991. Contaminated bottom sediment
capping demonstration in Elliott Bay. Proceedings of the
Conference Puget Sound Research '91.
Tavolaro, J. 1984. A Sediment Budget Study of Clamshell Dredging
and Ocean' Disposal Activities in the New York Bight. In
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140.
Truitt, C. L.. 1986. The Duwamish Waterway capping demonstration
project: Engineering analysis" and results of physical
monitoring. Technical Report D-86-2, US Army Waterways
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disposal. Environmental Effects of Dredging, Technical Notes,
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MS.
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Truitt, C. L. 1987. Engineering considerations for capping
subaqueous dredged material deposits — design concepts and
placement techniques. Environmental Effects of Dredging
Technical Note EEDP-01-4. US Army Waterways Experiment
Station, Vicksburg, MS.
Truitt, C. L. 1987. Engineering considerations for capping
subaqueous dredged material deposits — background and
preliminary planning. Environmental Effects of Dredging
Technical Note EEDP-01-3. US Army Waterways Experiment
Station, Vicksburg, MS.
Wang, X. Q., L. J. Thibodeaux, K. T. Valsaraj, and D. D. Reible.
1991. Efficiency of capping contaminated bed sediments_in
situ. 1. Laboratory-scale experiments on diffusion-adsorption
in the capping layer. Environ. Sci.-'Technol. 25(9): 1578-
1584.
Capping Bibliography
March
_
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DAMOS RELATED PAPERS
Arimoto,R. and S.Y.Feng. 1983. Changes in the levels of PCBs in Mvtilus edulis associated
with dredge spoil disposal. In: Wastes in the Ocean. Vol, It. Dredged Material Disposal
D.R. Kaster, I.W. Duedall, B.H. Ketchum and P.K. Parks, Editors. John Wiley and
Sons, Inc., New York. pp. 199-212.
Arimoto, R. and S.Y. Feng. 1983. BSstoIogical studies on mussels from dredge spoil dumpsite
J.Est. Coastal Shelf Sci.r 17: 535-546.
Bajek, J., Morton, R.W., Germane, J.D., and T. J. Fredette. 1987. Dredged material behavior
at a deep water open ocean disposal site. Proceedings of the Twentieth Dredging Seminar.
Western Dredging Association Annual Meeting, Toronto, Canada. September 1987 pp
95-107.
Bohlen, W.F. 1974. Continuous Monitoring Systems in Long Island Sound: Description and
Evaluation. Proceedings of the IEEE International Conference on Engineering in the Ocean
Environment. Halifax, Nova Scotia, August 1975, Volume 2: 61-69.
Bohlen, WJF. 1980. A Comparison between Dredger-Induced Resuspension of Sediments and
that Produced by Naturally Occurring Storm Events. Proceedings of the 17th Coastal
Engineering Conference, American Society of Civil Engineering NY NY
pg. 1700-1707. -=«..' e - - •>
Bohlen, W.F. 1982. Ih-Situ Monitoring of Sediment Resuspension in the Vicinity of Active
Dredge Spoil Disposal Areas. Oceans '82 MIS/IEEE Meeting, Washington DC
September 1982.
Bohlen, W.F. 1984. Evaluations of the Factors Governing the Mobility of Dredged Material
Placed at Open Water Disposal Sites. The 10th United States/Japan Experts Meeting on
Management of Bottom Sediments Containing Toxic Substances, Kyoto, Japan, November
Bohlen, W.F. 1985. On the Temporal Variability of Suspended Material Concentrations in
Estuaries. Estuaries, 8(2b): 113A.
Bohlen, W.F., and K.B. Winnick. 1985. Apparent Non-Linearities in the Magnitude of Storm
Induced Sediment Resuspension in Estuaries. EOS Trans. Amer. Geoohvs Union
66(51): 1260. : '
Bohlen, W.F., Rhoads, D.C., McCall, P., and R.W. Morton. 1986. The Impact of Hurricane
Gloria on Dredged Material Disposal Sites in Long Island Sound. Proceedings of the 6th
International Ocean Disposal Symposium. Asilomar, CA., April 21-25, 1986. p.184.
Bohlen, W.F. 1989. Ocean Disposal of Particulate Wastes: Practices, Properties and Processes
. In Geotechnical Aspects of Ocean Waste Disposal Eds: Demars, K.R, and Cheney, RC.
- Amer. Soc. for Testing and Materials, special publication.
Boon, J.D., Bohlen, W.F., and L.D. Wright, 1987. Estuarine Versus Inner Shelf Disposal Sites:
DAMOS Related Papers ~~I ~ 12/21/94
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A Comparison of Benthic Current Regimes. Proceedings of Coastal Sediments 1987.
ASCE,NewYork,NY.,VolumeI: 571-583.
Brandes H., Silva, A., and T. Fredette. 1991. Settlement of offshore mounds of capped dredged
materials. Maritimes 35DV12-14.
Vicksburg, MS.
°*
Station, Vicksburg, MS.
> R V., Arimoto, R., and S.Y. Feng. 1984. Field" _
monitoring of heavy metals at offshore dredged matenals
ICUlllUUU&O JLVUi '" yj.v~ »—«o »»•»• o
disposll sites. MTS Journal. 18(4):9-16.
J and R.W. Morton. 1984. Geotechnical
'dredge spoil disposal mounds. Offshore Technology
Conference, 16 p.
Experiment Station, Vicksburg, MS.
Experiment Station, Vicksburg, MS.
Rockville, MD. 161 pp.
'
International Council for the Exploration of the Sea, October, 1978, Copennagen.
Fredette, T.J. 1994. A summary of recent capping investigations with dredged sediments in
. • — : " 12/21/94
DAMOS Related Papers •*
-------
New England, USA. Proceedings of the 15th US/Japan Experts Meeting on Management
of Bottom Sediments Containing Toxic Substances, November, 1991, Los Angeles, CA.
Fredette, TJ. 1994. Disposal site capping management: New Haven Harbor. Proceedings of the
Second International Conference on Dredging and Dredged Material Placement, November
1994, Orlando, FL.
Fredette, T. J., Anderson,G., Payne, B.S., and J. D. Lunz. 1986. Biological monitoring of
open-water dredged material disposal sites. IEEE Oceans '86 Conference Proceedings
Washington, D.C., September 23-25, 1986. Pp. 764-769.
Fredette, T.J., Crawford, J.P., and J.C. DiPerna. In Press. Co-evolution of Harbor
Maintenance Dredging, Environmental Regulations, and Open-Water Disposal Site
Management: A Twenty-Year Perspective. Submitted to the Conference Ports '95 March
12-15, 1995, Tampa, FL.
Fredette, T. J., Germano, J. D., Kullberg, P. G., Carey, D. A., and P. Murray. 1992. Chemical
stability of capped dredged, material disposal mounds in Long Island Sound, USA.. ---•-•
Chemistry and Ecology 7:173-194.
Fredette, T. J, Kullberg, P.G., Carey, D.A., Morton, R.W., and J. D. Germano. 1992.
Twenty-five years of dredged material disposal site monitoring in Long Island Sound: A
long-termperspective. Proceedings of the Long Island Sound Research Conference, New
Haven, Connecticut.
Fredette, T. J., Morton, R.W., and J. D. Germano. 1987, Aquatic dredged material disposal in
New England. ASCE, NY, NY. Coastal Zone 87, Vol. 4, pp. 4268-4275..
Fredette, T. J., Morton, R.W.,"Bohlen, W.F., and D. C. Rhoads. 1988. Erosion and
resuspension effects of Hurricane Gloria at Long Island Sound dredged material disposal
sites. Corps of Engineers Seventh Seminar on Water Quality, Charleston NC February
1988. *'
Fredette, T.J., Bohlen, W.F., Rhoads, D.C., and R.W. Morton. 1989. Erosion and
Resuspension Effects of Hurricane Gloria at Long Island Sound Dredged Material Disposal
Sites. Environmental Effects of Dredging, Information Exchange Bulletin, Vol. D-89-2,
U.S. Army Corps of Engineers Waterways Experiment Station, Vicksburg, MS.
Gentile, J.H., and KJ. Scott. 1987. The Application of a Hazard Assessment Strategy to
Sediment Testing: Issues and Case Study. In: Fate and Effects of Sediment Bound
Chemicals in Aquatic Systems pg 167-187 Eds: Dickson, K.L., Maki, A.W.,.and
Brungs, W.A. Published by Pergamon Press, New York.
Germano, J.D. 1983. High Resolution Sediment Profiling with REMOTS Camera System Sea
Technology 24, 35-41.
Germano, J.D. and D.C. Rhoads. 1984. REMOTS Sediment Profiling at the Field Verification
Program (FVP) Disposal Site. Dredging and Dredge Material Disposal, Volume I, pg. 536-
544.. JEds: R.L. Montgomery and J.W. Leach, Published by ASCE, New York.
Germano, J.D., Rhoads, D.C., Boyer, L.F., Menzie, C.A., and J.A. Ryther, Jr. 1984.
REMOTS Imaging and Side Scan Sonar. Efficient Tools for Mapping Sea Floor
DAMOS Related Papers 3 ! 12/21/94
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Topography,Sediment Type, Bedforms, and Biology, Proceedings of the 4th International
Ocean Disposal Symposium. Ed: I. W. Duedall.
E T J Fredette. and D A. Carey. 1994. Underwater environmental survey
otionsusSgS^^^
'94 Conference, 7-10 February 1994, San Diego, CA.
Woods Hole, Mass.
Sons, New York. pp. 99-121.
Morton, R/W., Andreliunas, A., Crawford J.P, and S. ^ongdon^ ^gtion of Management
and Monitoring of Dredged Material Disposal in New England Waters.
Morton R. W Lindsay CJ and R. C. Semonian. 1984. Use of Scientific Data for
Published by ASCE, New York.
Morton R.W., and RJD. Jones. 1985. The Importance of Accurate Natation in Environmental
Assessment Programs. In: Sea lechnology.. August, 1985.
Morton, R.W 1987. Recent Studies Concerning the Capping of Contaminated Dredged .Material:
TMted StatestfapanExperts Meeting on Management of Bottom Sediments Containing
Toxic Substances. November 3-6, 1987. Baltimore MD.
Morton,R.W 1988. Monitoring me Effectiveness of Capping for Isolating Contaminated
Sedhnente: National Restarch Council Symposium on Contaminated Marine Sediments.
May 3 1-June 2, 1988. Tampa FL.
Morton R.W 1988. Monitoring of Open Water Dredged Material Disposal in
21st Dredging Seminar, Western Division ASCE, Texas A&M University, October 20-21,
1988.
Morton RW andD Porta. 1989. Use of Acoustic Instmme^ltation for Monitoring Dredged
M^terik^isposal Sites: Symposium on Geotechnical Aspects of Ocean Waste Disposal.
ASTM Meeting, January 22-27, 1989. Orlando FL.
Murray P Carey, D., and TJ. Fredette. 1994. Chemical flux of pore water through sediment
ycaps Proceedings of the Second International Conference on Dredging and Dredged
Material Placement, November 1994, Orlando, FL.
Murray P "SeAngelo, E., Parker, J., and TJ. Fredette. 1994. Integrated Acoustic Seafloor
yCha^eriStion. Proceedings of the Second International Conference on Dredging and
Dredged Material Placement, November 1994, Orlando, FL.
DAMOS Related Papers
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Palermo, M., Fredette, T.J., and R. E. Randall. 1992. Monitoring considerations for capping.
Dredging Research Technical Note DRP-5-07, US Army Corps of Engineers Waterways
Experiment Station, Vicksburg, MS.
Parker, J. W. Monitoring and Management of Dredged Material Disposal and Capping. Science
Applications International Corporation (SAIC).
Phelps, D.K., Katz, C.H., Scott, K.J., and B.H. Reynolds. 1987. Coastal Monitoring:
Evaluation of Monitoring Methods in Narragansett Bay, Long Island Sound and New York
Bight, and aGeneral Monitoring Strategy. In New Approaches to Monitoring Aquatic
Ecosystems, pg. 107—124. Ed: T.P. Boyle, American Society of Testing and Materials
STP 940, Philadelphia, PA.
Ray, G.L., Clarke, D.G., Wilbur, TJ?., and T.J. Fredette. 1994. Construction of intertidal
mudflats as a beneficial use of dredged material. Proceedings of the Second International
Conference on Dredging and Dredged Material Placement, November 1994, Orlando, FL.
Rhoads, D. C., and J. D. Germano. 1986. Interpreting long-term changes in benthic community
structure: A new protocol. Hydrobiologia 142. 291-308.
Rhoads, D. C., and J. D. Germano. 1990. The Use of REMOTS Imaging Technology for
Disposal Site Selection and Monitoring, pp 50-64. In: Geotechnical Engineering of Ocean
Waste Disposal.
Rhoads, D. C., and J. D. Germano. 1989. The Use of REMOTS Imaging Technology for
Disposal Site Selection and Monitoring: Symposium on Geotechnical Aspects of Ocean
Waste Disposal. January 22-27 1989 Meeting of the ASTM. Orlando, FL.
Rhoads, D.C., Kullberg, P.G., and TJ. Fredette. In Press. Dredged Material Disposal Within
An Estuary: Is It A Significant Source Of Sediment And Contaminant Fluxes? The Case Of
Long Island Sound. Submitted to the Conference, Ports '95, March 12-15,1995, Tampa,
FL.
Scott, J., Rhoads, D.C., Rosen, J., Pratt, S., and J. Gentile. 1987. Impact of Open-Water
Disposal of Black Rock Harbor Dredged Material on Benthic Recolonization at the FVP
Site: U.S. Aimy Corps of Engineers Technical Report D-87-4, U.S. Army Engineer
Waterways Experiment Station, Vicksburg, Mississippi.
Scott, K.J., and M.S. Redmond. The Effects of a Contaminated Dredged Material on>Laboratory
Populations of the Tubicolous Amphipod Ampelisca abdita. In: Aquatic Toxicology and
Hazard Assessment: 12th Volume. Eds: Cowgill, U.M., and L.R. Williams. ASTM STP
1027. Philadelphia, PA.
Scott, KJ. Effects of Contaminated Sediments on Marine Benthic Biota and Communities.
NAS/National Research Council Symposium — Contaminated Marine Sediments:
Assessment and Remediation.
Shonting, D:H;, and R.W. Morton. 1981. The New England Disposal Area Monitoring System
and the Stamford-New Haven Capping Experiment, Pollution in the Oceans; pp. 13M72.
Silva, A.J., Brandes, H.G., Uchytil, C.J., Fredette, TJ., and D. Carey. 1994. Geotechnical
DAMOS Related Papers 5 12)21/94
-------
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Conference on Dredging and Dredged Material Placement, November 1994, Orlando, EL
Stewart, L.L. 1982. Chapt 10. Chronological Records Obtained by Diver Survey at the New
London and New Haven Dredge Disposal Sites. In: Impact of Marine Pollution on
Society, pg. 173-194. Eds: Tippie, V.K., and D.R. Kester. Praeger Publishers, New
York.
Stewart, LX., Auster, P., and A. Shepard. 1985. Remote Operated Vehicle (ROV-Recon IV)
Survey of Benthic Conditions at Dredged Material Disposal off New England. R.O.V. '85
Conference Proceedings, 2-4 April 1985, San Diego, CA. Mar. Tech. Soc.. 3: 137-145.
i
Stewart, LX. 1986. In-Situ Assessment of Faunal-Sediment Ecology at Deep (100 meter) New
England Dredged Material Disposal Sites. Sixth International Ocean Disposal Symposium.
Pacific Grove, CA. Abstract. -" '"!:
Sumeri, A,, Fredette, T.J., Kullberg, P.G., Germano, J.D., and P. Pechko. 1991. Sediment
chemistry profiles in capped dredged material disposal deposits: results from three US
Army Corps of Engineer offices. Proceedings of the Twenty-fourth Annual Dredging
Seminar, Las Vegas, Nevada. Pp. 161-187.
Tramontane, JJvl, and W.F. Bohlen. 1982. The Nutrient and Trace Metal Geochemistry of a
Dredge Plume. J. Estuarine. Coastal and Shelf Sci.. 18: 385-401.
Wiley, MB., Carey, D.5 Fredette, T.J., and W.F. Bohlen. 1994. Dredged material accumulation
at a dispersive disposal site. Proceedings of the Second International Conference on
Dredging and Dredged Material Placement, November 1994, Orlando, FL.
Zajac R.N., and R.B. Whitlatch. 1988. Population Ecology of the Polychaete Nepthys incisa in
Southern New England Waters and the Effects of Disturbance. Estuaries 11(2): 117-133.
DAMOS Related Papers
. 12/21/94
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-------
111 1111 'I I III I 111
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111 1 Hill mUiiM 1I1I11I Ill ii I1 ililill"! Illlill
111 )• iiiiiii'iiiiiiiiihiiiiii: |I|.B
I" II
lllll I II
I i iiiiiii
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Chapter Eleven: List Of Agencies, Organizations And
Persons To Whom The FEIR/S Has
Been Sent
UNITED STATES SENATORS:
MR JERRY KAVANAUGH
COMMITIEE ON LABOR
428 SENATE OFFICE BUILDING
WASHINGTON DC 20510
HONORABLE EDWARD M. KENNEDY
UNITED STATES SENATE
WASHINGTON, DC 20510-2101
HONORABLE EDWARD M. KENNEDY
UNITED STATES SENATOR
2400 JFK FEDERAL BLDG.
BOSTON, MA 02203
HONORABLE JOHN F. KERRY
UNITED STATES SENATE
WASHINGTON, DC 20510-2102
HONORABLE JOHN F. KERRY
UNTIED STATES SENATOR
ONE BOWDOIN SQUARE
TENTH FLOOR
BOSTON, MA 02114
UNITED STATES CONGRESSMEN:
HONORABLE PETER I. BLUTE
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2103
HONORABLE PETER I. BLUTE
REPRESENTATIVE IN CONGRESS
1079 MECHANICS TOWER
WORCESTER, MA 01608
HONORABLE BARNEY FRANK
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2104
HONORABLE BARNEY FRANK
REPRESENTATIVE IN CONGRESS
29 CRAFT STREET
NEWTON, MA 02158
HONORABLE JOSEPH P. KENNEDY, H
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2108
HONORABLE JOSEPH P. KENNEDY, H
REPRESENTATIVE IN CONGRESS
THE SCHRAFT CENTER, SUITE 605
529 MAIN STREET
CHARLESTOWN, MA 02129
HONORABLE EDWARD J. MARKEY
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2107
HONORABLE EDWARD J. MARKEY
REPRESENTATIVE IN CONGRESS
SUITE 101, 5 HIGH STREET
MEDFORD, MA 02155
HONORABLE MARTIN T. MEEHAN
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2105
HONORABLE MARTIN T. MEEHAN
REPRESENTATIVE IN CONGRESS
11 LAWRENCE ST, STE. 806
LAWRENCE, MA 01840
HONORABLE JOHN J. MOAKLEY
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2109
HONORABLE JOHN J. MOAKLEY
REPRESENTATTVE IN CONGRESS
220 WORLD TRADE CENTER
BOSTON, MA 02110
HONORABLE RICHARD E. NEAL
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2102
HONORABLE RICHARD E. NEAL
REPRESENTATIVE IN CONGRESS
4 CONGRESS ST.
MILFORD, MA 01757
HONORABLE JOHN W. OLVER
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2101
11-1
-------
HONORABLE JOHN W. OLVER
REPRESENTATIVE IN CONGRESS
FEDERAL BUILDING
PITTSEIELD, MA 01201
HONORABLE GERRY E. STUDDS
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2110
HONORABLE GERRY E. STUDDS
REPRESENTATIVE IN CONGRESS
146 MAIN STREET
HYANNIS, MA 02601-3128
HONORABLE PETER G. TORKILDSEN
HOUSE OF REPRESENTATIVES
WASHINGTON, DC 20515-2106
HONORABLE PETER G. TORKILDSEN
REPRESENTATIVE IN CONGRESS
70 WASHINGTON STREET
SALEM, MA 01970-3580
STATE GOVERNOR:
HONORABLE WILLIAM F. WELD
GOVERNOR OF THE COMMONWEALTH OF
MASSACHUSETTS
STATE HOUSE
BOSTON, MA 02133
STATE SENATORS:
THE HONORABLE WILLIAM M. BULGER
SENATE PRESIDENT
MASSACHUSETTS STATE SENATE
ROOM 332
BOSTON, MA 02133
THE HONORABLE WALTER J. BOVERBSH
MASSACHUSETTS STATE SENATE ROOM 333
BOSTON, MA 02133
THE HONORABLE THOMAS F. BIRMINGHAM
MASSACHUSETTS STATE SENATE ROOM 212
BOSTON, MA 02133
PAT ELDRIDGE
SENATOR HENRI RAUSCHENBACH'S OFFICE
ROOM 315 STATE HOUSE
BOSTON, MA 02133
THE HONORABLE ROBERT E. TRAVAGLINI
MASSACHUSETTS STATE SENATE
ROOM416A
BOSTON, MA 02133
THE HONORABLE PAUL WHITE
MASSACHUSETTS STATE SENATE ROOM 309
BOSTON, MA 02133
STATE REPRESENTATIVES:
THE HONORABLE JAMES BRETT
HOUSE OF REPRESENTATIVES STATE HOUSE
ROOM 42
BOSTON, MA 02133
THE HONORABLE S ALVATORE DMASI
HOUSE OF REPRESENTATIVES STATE HOUSE
ROOM 138
BOSTON, MA 02133
THE HONORABLE THOMAS FINNERAN
HOUSE OF REPRESENTATIVES STATE HOUSE
ROOM 243
BOSTON, MA 02133
THE HONORABLE ROBERT HALVERN
CHAIRMAN, JOINT COMMITTEE ON
TRANSPORTATION
HOUSE OF REPRESENTATIVES STATE HOUSE
ROOM 443
BOSTON, MA 02133
THE HONORABLE JOHN KLIMM
HOUSE OF REPRESENTATIVES STATE HOUSE
ROOM 146
BOSTON, MA 02133
THE HONORABLE EMMANUEL G. SERRA
HOUSE OF REPRESENTATIVES STATE HOUSE
ROOM 481
BOSTON, MA 02133
11-2
-------
THE HONORABLE RICHARD YOKE
HOUSE OF REPRESENTATIVES STATE HOUSE
ROOM 343
BOSTON, MA 02133
MICHAEL C. WOOD
TOWN ADMINISTRATOR
TOWNOFNAHANT
NAHANT MA 01908
MUNICIPAL GOVERNMENT:
CITY CLERK
CITY OF GLOUCESTER
GLOUCESTER MA 01930
ROBERT N. FORMAN, CHAIRMAN
BOARD OF SELECTMEN
TOWNOFNAHANT
334 NAHANT ROAD
NAHANT MA 01908
THE HONORABLE JOHN R. MCCARTHY
MAYOR, CITY OF EVERETT
484 BROADWAY STREET
EVERETT, MA 02149
THE HONORABLE THOMAS M. MENINO
MAYOR, CITY OF BOSTON
BOSTON CITY HALL FIFTH FLOOR
BOSTON, MA 02201
ROBERT W. MURPHY, CHAIRMAN
BOARD OF SELECTMEN
TOWN OF SWAMPSCOTT
ELIHU THOMSON ADMINISTRATION BUILDING
SWAMPSCOTT MA 01907
THE HONORABLE JAMES A. SHEETS
MAYOR, CITY OF QUINCY
1304 HANCOCK STREET
QUINCY, MA 02169
BRUCE H. TOBEY MAYOR
CITY OF GLOUCESTER
GLOUCESTER MA 01930
MARIE T. TURNER, CHAIR
WINTHROP BOARD OF SELECTMAN
1METCALF SQUARE
WINTHROP, MA 02152
FEDERAL AGENCIES:
MR. BRAD B ARR MANAGER
NOAA/STELLWAGEN BANK NMS
14 UNION STREET
PLYMOUTH, MA 02360
US FISH & WILDLIFE SERVICE
RALPH PILL MARKETPLACE,
4TH FLOOR 22 BRIDGE STREET
CONCORD, NH 03301-4901
ATTN: MR. MICHAEL BARTLETT, SUPERVISOR
VERNON B.LANG
MR. BRUCE BLANCHARD DIRECTOR
US DEPARTMENT OF THE INTERIOR
OFFICE OF ENVIONMENTAL PROJECT REVIEW
WASHINGTON, DC 20240
MR. RON BROWN SECRETARY
US DEPARTMENT OF COMMERCE
HOOVER BUILDING
14TH & CONSTITUTION AVENUE
WASHINGTON, DC 20230
BRADBUTMAN
US GEOLOGICAL SURVEY
BRANCH OF ATLANTIC MARINE GEOLOGY
QUISSETT CAMPWOODS HOLE, MA 02543
LT. TED COATES
US COAST GUARD MARINE SAFETY OFHCE
455 COMMERCIAL ST
BOSTON MA 02109-1045
US ENVIRONMENTAL PROTECTION AGENCY
J. F. KENNEDY BUILDING
BOSTON, MA 02203
ATTN: MR. JOHN DEVUJLARS DIRECTOR
PHIL COLARUSSO
ED REINER
MS. PATIENCE WRITTEN
11-3
-------
LT PATRICK G. FORAN
FIRST COAST GUARD DISTRICT
408 ATLANTIC AVENUE
BOSTON, MA 02110
DR. NORBERT A. JAWORSKI
ENVIRONMENTAL RESEARCH LABORATORY
U.S. ENVIRONMENTAL PROTECTION AGENCY
27TARZWELLDR.
NARRAGANSETT RI02882
MR, SCOTT M. KAVANAUGH OFFICER-IN-
CHARGE, US NAVY COMNAVBASE
DETACHMENT BOSTON
CHARLESTOWN NAVY YARD BUILDING 24
CHARLESTOWN, MA 02129
MR JAMES LAWLESS, DEPUTY DIRECTOR
NATIONAL OCEAN SERVICE - NOAA
ROOM 11515
1335 EAST WEST HIGHWAY
SILVER SPRINGS MD 20910
GORDON LHCH
US DEPARTMENT OF THE INTERIOR
OFFICE OF ENVIRONMENTAL POLICY
ROOM 2340
1849 C STREET, NW
WASHINGTON, DC 20240
MS.JOLINSE
NOAA/ORCA22
BIN NO 15700
7600 SAND POINT WAY NE
SEATTLE, WA 98115-0070
FRANCIS MARDULA
US DEPARTMENT OF TRANSPORTATION
MARAD ROOM 7221 MAR-224
400 7TH STREET, SW
WASHINGTON, DC 20590
ROBERT MCKEON DIRECTOR,
NORTH ATLANTIC REGION MARITIME
ADMINISTRATION
DEPT. OF TRANSPORTATION
26 FEDERAL PLAZA R-3737
NEW YORK NY 10278
LCDR TED GATES
US COAST GUARD MARINE SAFETY OFFICE
455 COMMERCIAL STREET
BOSTON, MA 02109-1045
JACOB PATNAIK
US COAST GUARD MARINE SAFETY OFFICE
BRIDGE ADMINISTRATION DIVISION, G-NBR-3
2100 SECOND STREET, S.W.
WASHINGTON, DC 20593
MARGHERJTA PRYOR
OCEANS AND COASTAL PROTECTION DIV.
U.S. ENVIRONMENTAL PROTECTION AGANCY
401 M STREET SW MAIL CODE 4504F
WASHINGTON DC 20960
ANDREW L. RADDANT
US DEPARTMENT OF THE INTERIOR
OFFICE OF ENVIRONMENTAL POLICY AND
COMPLIANCE
408 ATLANTIC AVENUE ROOM 142
BOSTON MA 02210-3334
NATIONAL MARINE FISHERIES SERVICE
ONE BLACKBURN DRIVE
GLOUCESTER, MA 01930-2298
ATTN: MR. RICHARD ROE DIRECTOR
JONATHAN KURLAND
CHRIS MANTZARIS
WILLIAM ROBINSON
MR. DAVID ROSE
NATIONAL PARK SERVICE
CHARLESTOWN NAVY YARD
CHARLESTOWN, MA 02129
BECKY TUDDEN
US ENVIRONMENTAL PROTECTION AGENCY
W33
75 HAWTHORN STREET
SAN FRANSISCO, CA 94105
DONNA WIETING ACTING DIRECTOR,
ECOLOGY AND CONSERVATION OFFICE
US DEPARTMENT OF COMMERCE
OFFICE OF THE UNDER SECRETARY FOR
OCEANS AND ATMOSPHERE
WASHINGTON DC 20230
11-4
-------
MS. JOAN YIM, DEPUTY ADMINISTRATOR
US MARITIME ADMINISTRATION
US DEPT OF TRANSPORTATION
OFFICE OF PORT AND INTERMODAL
400 SEVENTH STREET, SW
WASHINGTON, DC 20590
STATE AGENCIES:
THE HONORABLE STEVEN V. ANGELO
CHAIR, NATURAL RESOURCES &
AGRICULTURE
ROOM 473F STATE HOUSE
BOSTON, MA 02133
MS. NANCY BAKER
MA EXECUTIVE OFFICE OF ENVIRONMENTAL
AFFAIRS, ROOM 2000 100 CAMBRIDGE STREET
BOSTON, MA 02202
COASTAL TONE MANAGEMENT
ROOM 2006 100 CAMBRIDGE STREET
BOSTON, MA 02202
ATTN: MS. PEG BRADY, DIRECTOR
DEERIN B ABB-BROTT
MA DIVISION OF MARINE FISHERIES
100 CAMBRIDGE STREET
BOSTON, MA 02202
ATTN: MR. PHILIP COATES DIRECTOR
LEIGH BRIDGES
MARIANN CONNOLLY
MWRA PROGRAM MANAGEMENT DIVISION
100 FIRST AVENUE - BUILDING 39
CHARLESTOWN NAVY YARD
CHARLESTOWN, MA 02129
MR. JAY COPELAND
DIVISION OF FISHERIES & WILDLIFE
NATURAL HERITAGE & ENDANGERED SPECIES
PROGRAM
100 CAMBRIDGE STREET
BOSTON, MA 02202
MR. STEVEN CORBETT
DIRECTOR OF ADMEN SUPPORT DIVISION
MA WATER RESOURCES AUTHORITY
100 FIRST AVENUE
CHARLESTOWN, MA 02129
JON COSCO
MERRIMACK VALLEY PLANNING COMMISSION
160 MAIN STREET
HAVERHGLL, MA 01830
MS. TRUDY COXE, SECRETARY
MA EXECUTIVE OFFICE OF ENVIRONMENTAL
AFFAIRS, ROOM 2000 100 CAMBRIDGE STREET
BOSTON, MA 02202
COLIN M. CUNNINGHAM, CHAIRMAN
MARINE FISHERIES COMMISSION
COMMONWEALTH OF MASSACHUSETTS
LEVERETT SALTONSTALL STATE OFFICE
BUILDING
100 CAMBRIDGE STREET
BOSTON MA 02202
MS. MAGGIE DEBBIE
MASS WATER RESOURCES AUTHORITY
CHARLESTOWN NAVY YARD
100 FIRST AVENUE
CHARLESTOWN, MA 02129
MA DEPT OF ENVIRONMENTAL PROTECTION
DIVISION OF WETLANDS & WATERWAYS
8TH FLOOR
1 WINTER STREET
BOSTON, MA 02108
ATTN: MR. CARL DffiRKER, ACTING DIRECTOR
MITCH ZIENCINA
MA DEPT OF ENVIRONMENTAL PROTECTION
WATER POLLUTION CONTROL
1 WINTER STREET
BOSTON, MA 02108
ATTN: MR. BRIAN DONAHOE, DIRECTOR
JUDY PERRY
MR. MICHAEL GILDESGAME
OCEAN SANCTUARIES COORDINATOR
MA DIVISION OF WATER RESOURCES
13TH FLOOR
100 CAMBRIDGE STREET
BOSTON, MA 02202
11-5
-------
MS.ASTRIDGLYNN
DIRECTOR OF TRANSIT
EXECUTIVE OFFICE OF TRANSPORTATION &
CONSTRUCTION
ROOM 3170
10 PARK PLAZA
BOSTON, MA 02116
DANIEL GREENBAUM, COMMISSIONER
MA DEPT OFENVIRONMENTAL PROTECTION
ONE WINTER STREET
BOSTON, MA 02108
MR. JOEL HARTLEY
MA DEPT OF ENVIRONMENTAL PROTECTION
SOLID WASTE MANAGEMENT
1 WINTER STREET
BOSTON, MA 02108
CHRISTOPHER LAM
MWRA, CHARLESTOWN NAVY YARD
100 FIRST AVENUE
CHARLESTOWN, MA 02129
MR. JOEL A. LERNER, DIRECTOR
MA DIVISION OF CONSERVATION SERVICE
100 CAMBRIDGE STREET
BOSTON, MA 02202
MR LESLIE LEWIS
MADEPT OFENVIRONMENTAL MANAGEMENT
100 CAMBRIDGE ST., RM 1905
BOSTON, MA 02202
MR, STEVEN G. LJPMAN
BOSTON HARBOR COORDINATOR
MA DEPT OFENVIRONMENTAL PROTECTION
1 WINTER STREET
BOSTON, MA 02108
MR. VIC MASTONE, DIRECTOR
MA EXECUTIVE OFFICE OF ENVIRONMENTAL
AFFAIRS
BOARD OFUNDERWATER ARCHEOLOGY
100 CAMBRIDGE STREET
BOSTON, MA 02202
MS. JOANNE MCBRJEN
MA DEPT OF ENVIRONMENTAL AFFAIRS
DIVISION OF ENERGY RESOURCES, ROOM 1500
100 CAMBRIDGE STREET
BOSTON, MA 02202
MS. JUDITH MCDONOUGH
EXECUTIVE DIRECTOR
MASS STATE HISTORICAL COMMISSION
80 BOYLSTON STREET
BOSTON, MA 02116
MICHAEL B. MCHALE H INTERN DEM
6 APPLECREST ROAD
ANDOVER, MA 01810
MS. JULIA O'BRIEN
MDC PLANNING OFFICE
20 SOMERSET STREET
BOSTON, MA 02108
MARY PADULA, COMMISSIONER
MASS. EXECUTIVE OFFICE OF COMMUNITIES
AND DEVELOPMENT, ROOM 1804
100 CAMBRIDGE STREET
BOSTON, MA 02202
MRMARK RADVILLE
PROJECT MANAGER, ENVIRONMENTAL
MANAGEMENT
MA WATER RESOURCES AUTHORITY
100 FIRST AVENUE
CHARLESTOWN, MA 02129
STEPHEN J. REMEN, COMMISSIONER
MASS. EXECUTIVE OFFICE OF ECONOMIC
AFFAIRS
DIVISION OF ENERGY RESOURCES
100 CAMBRIDGE STREET ROOM 1500
BOSTON, MA 02202
MS. STACY A. RICHARDS
AGENCY COORDINATOR
MASSACHUSETTS HIGHWAY DEPARTMENT
CENTRAL ARTERYnUNNEL
ONE SOUTH STATION
BOSTON, MA 02110
11-6
-------
MR JOHN A. SIMPSON
MA DEPT OF ENVIRONMENTAL PROTECTION
WATERWAYS DIVISION
ONE WINTER ST.
BOSTON MA 02108
MS. CASSIE THOMAS
MA DEPT OF ENVIRONMENTAL MANAGEMENT
SCENIC RIVERS PROGRAM , ROOM 1404
100 CAMBRIDGE STREET BOSTON, MA 02202
HMANSHU VAKIL
CENTRAL ARTERY/TUNNEL PROJECT
MAIL STOP 02-3X-01
ONE SOUTH STATION
BOSTON MA 02210
MR. PETER WEBBER, COMMISSIONER
MA DEPT OF ENVIRONMENTAL MANAGEMENT
DIVISION OF WATERWAYS
100 CAMBRIDGE STREET 14TH FLOOR
BOSTON, MA 02202
MR. PETER M. ZUK, PROJECT DIRECTOR
MASSACHUSETTS HIGHWAY DEPARTMENT
CENTRAL ARTERY/TUNNEL
ONE SOUTH STATION
BOSTON, MA 02110
MUNICIPAL OFFICES:
BOSTON POLICE DEPARTMENT
HARBOR PATROL UNIT 154
BERKELEY STREET
BOSTON, MA 02116
NEWBURYPORT HARBOR COMMISSION
CITY HALL
NEWBURYPORT, MA 01950
CHAIRMAN, PLANNING BOARD
TOWN OF SWAMPSCOTT, TOWN HALL
MONUMENT AVE
SWAMPSCOTT MA 01907
NAHANT HISTORICAL SOCIETY
C/O SEARS
P. O. BOX 42
NAHANT, MA 01908
CITY COUNCIL
CITY Ofc GLOUCESTER
GLOUCESTER MA 01930
MR. ARMANDO J. CARBONELL
EXECUTIVE DIRECTOR
CAPE COD COMMISSION
3225 MAIN STREET P.O. BOX 226
B ARNSTABLE, MA 02630
ROBERT J. CIOLEK, EXECUTIVE DIRECTOR
BOSTON WATER AND SEWER COMMISSION
425 SUMMER STREET
BOSTON, MA 02210-1700
MR. BRIAN DELOREY, ASSISTANT DIR.
FOR ECONOMIC DEVELOPMENT
BOSTON REDEVELOPMENT AUTHORITY
ONE CITY HALL SQUARE
BOSTON, MA 02201-1007
JOHN DEPRffiST, PROJECT MANAGER
TRAFFIC & TRANSPORTATION
CHELSEA DEPT. PLANNING & COMMUNITY
DEVELOPMENT, CITY HALL, ROOM 101
500 BROADWAY
CHELSEA, MA 02150
JOSEPH GRAUL, COMMISSIONER
NAHANT CONSERVATION COMMISSION
TOWN HALL
NAHANT ROAD NAHANT, MA 01908
WILLIAM F. HENNESSEY, CHAIRMAN
HARBOR ADVISORY COMMITTEE
TOWN OF SWAMPSCOTT ADMINISTRATION
BUILDING
SWAMPSCOTT, MA 01907
MR. DOUG HERBERICH
EDIC
43 HAWKINS ST
BOSTON MA 02114
MR. CHRISTOPHER KELLY
EXECUTIVE SECRETARY
BOSTON CONSERVATION COMMISSION
ROOM 805
BOSTON CITY HALL
BOSTON, MA 02201
11-7
-------
MR. RICHARD B. MERTENS
BOSTON REDEVELOPMENT AUTHORITY
ONE CITY HALL SQUARE
BOSTON, MA 02201
LAWRENCE PICARELLO, CHAIRMAN
CONSERVATION COMMISSION
TOWN OF SWAMPSCOTT
ELfflU THOMSON ADMINISTRATION BUILDING
SWAMPSCOTT, MA 01907
MR. MARTIN PILLSBURY
METROPOLITAN AREA PLANNING COUNCIL
60 TEMPLE PLACE
BOSTON, MA 02111
ENVIRONMENTAL DEPARTMENT
BOSTON CITY HALL
BOSTON, MA 02201
ATTN: MR. ARTHUR PUGSLEY
NAOMI SCHUSSTER
MR. PETER SCARPIGNATO
DEPARTMENT OF PUBLIC WORKS
ONE CITY HALL SQUARE
BOSTON, MA 02201
MR JIM SORRENTTNO
EDIC
10 DRYDOCK AVENUE
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LEWIS H. SPENCE, RECEIVER
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JOHN P. SULLIVAN, CHIEF ENGINEER
BOSTON WATER AND SEWER COMMISSION
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MS KATHDS PETERS, CLERK
CAPE COD COMMISSION
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666 BOYLSTON STREET
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595 BROADWAY
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EVERETT PUBLIC LIBRARY
410 BROADWAY
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2 METCALF SQUARE
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DEPT.- KS DOCUMENTS DEPARTMENT
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SAVE THE HARBOR/SAVE THE BAY
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POLLY BRADLEY
NAHANT SWIM, INC.
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MS. PRISCILLA CHAPMAN
EXECUTIVE DIRECTOR SIERRA CLUB
3 JOY STREET
BOSTON, MA 02108
BILLCOFFEY
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35 EMERALD ROAD
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434 SMITH STREET
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MS. CINDY DELPAPA
MA AUDUBON SOCIETY
346 GRAPEVINE ROAD
WENHAM, MA 01984
MS NIAZ DORRY MANAGER, TOXICS
CAMPAIGN
GREENPEACE
1436 U STREET, NW
WASHINGTON D.C. 20009
MR. DAVID DOW, CHAIR
SIERRA CLUB CAPE COD CHAPTER
18TREETOPLANE
EAST FALMOUTH, MA 02536-4814
11-9
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ETTAB.GOODSTEIN
S.T.O.P.
530 ROUTE 28
WEST DENNIS, MA 02670
MR. DONR. mCKMAN
DIRECTOR OF MEDIA RELATIONS
MA AUDUBON SOCIETY
SOUTH GREAT ROAD
LINCOLN, MA 01773
JOHNLEWIS
SIERRA CLUB NEW ENGLAND CHAPTER
97 NEWBURY STREET
BOSTON, MA 02116
MARYE. LOEBIG, COCHAIR S.T.OP.
63 MEADOWSPRING DRIVE
SOUTH DENNIS, MA 02663
SUSAN NICKERSON
APCC
PO BOX 636
ORLEANS, MA 02653
NOELLERONAN
CETACEAN RESEARCH UNIT
966 ROUTE 78
JAVA CENTER, NY 14082
ROSEMARY SETON
CETACEAN RESEARCH UNIT
33 BROADWAY APARTMENT 2
ROCKPORT, MA 01966
JENNIFER SHEA
CETACEAN RESEARCH UNIT
126 AMSTERDAM ROAD
ROCHESTER, NY 14610
SUSAN STABLES
S.T.O.P.
26 MARSHVIEW CIRCLE
EAST SANDWICH, MA 02537
STOP
63 MEADOWSPRING DR
SOUTH DENNIS MA 02660
MAXSTRAHAN
GREENWORLD, SUITE 193 510
COMMONWEALTH AVENUE
BOSTON, MA 02215
JODISUGERMAN, POLICY DIRECTOR
SAVE THE HARBOR/SAVE THE BAY
25 WEST STREET FOURTH FLOOR
BOSTON, MA 02111
MASON WFJNRICH, EXECUTIVE DIRECTOR
CETACEAN RESEARCH UNIT 18
COASTAL ADVOCACY NETWORK
PO BOX 159
GLOUCESTER, MA 01930
MASON WEINRICH, CHAIRMAN
COASTAL ADVOCACY NETWORK
C/O MASSACHUSETTS BAYS PROGRAM
100 CAMBRIDGE STREET
BOSTON MA 02202
LESLYNL.ZAK
CETACEAN RESEARCH UNIT
33 BROADWAY #2
ROCKPORT, MA 01966
MS. MARINA ZELLNER, PRESIDENT
LEAGUE OF WOMEN VOTERS OF LOWER CAPE
COD
PO BOX 460
WEST CHATHAM, MA 02669
PRIVATE ENTITIES AND
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IEP INC WETLANDS GROUP
PO BOX 1840
SANDWICH, MA 02563
CONSERVATION COORDINATOR
NEW ENGLAND AQUARIUM
CENTRAL WHARF
BOSTON, MA 02110
NUCQ VINE ASSOCIATES
253 LOUIS STREET
NEWBURYPORT, MA 01950
11-10
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MR WILLIAM ADLER
MA LOBSTERMAlSrS ASSOCIATION, INC.
80 OTIS PLACE BOX 600
SCJTUATE, MA 02066-0006
DOROTHY ALLEN
12EENNOWAY
NAHANT, MA 01908
NICOLA ARENA, PRESIDENT
CONTAINERSHIP AGENCY, INC.
420 FIFTH AVE.
NEW YORK NY 10018-2702
MR. DAVID P. ARGYROS, MANAGER
SAFETY & ENVIRONMENTAL COMPLIANCE CH
SPRAGUE & SON CO
ONE PARADE MALL
PORTSMOUTH, NH 03801
MR. GEORGE AUCHY, CONSULTANT
SLIP 104, ADMIRAL HILL MARINA
1000 JUSTIN DRIVE
CHELSEA, MA 02150
JOHN BABEL
HMM ASSOCIATES
196 BAKER AVENUE
CONCORD, MA 01742
RUSSEL BARNABY, PROJECT COORDINATOR
CHAMBER COMMERCE
CENTER MANAGEMENT OFFICE
50 TERMINAL STREET
CHARLESTOWN MA 02129
JASON BOEHK
34 BELKNAP ST., APT 1
SOMERVJLLE MA 02144
MS. PATRICIA BONANNO
PO BOX 1545
BUZZARDS BAY, MA 02532
ARTHUR J. BOYLE, SENIOR VICE PRESIDENT
I.T.O. CORPORATION OF NEW ENGLAND
P.O. BOX 65
SOUTH BOSTONMA 02127
MARGARET B. BRIGGS
HMM ASSOCIATES
196 BAKER AVENUE
CONCORD, MA 01742
CHERYL BROWNLEE
34 BELKNAP ST.
SOMERVJLLE MA 02144
MS. GLORIA BRUNDAGE
POBOX61
YARMOUTH PORT, MA 02645
RON BUTT
ENSEARCH ENVIRONMENTAL CORPORATION
211 CONGRESS STREET
BOSTON, MA
CPT. ROBERT CALDER
THE BOSTON SHIPPING ASSOCIATION
MS. BEVERLY M. CARNEY
38 LONGVIEW DRIVE
ORLEANS, MA 02653
NANCY CASE, PRESIDENT
LADS SYSTEMS, INC.
810 THIRD AVENUE SUITE 408 SEATTLE, WA
98104
MR. MICHAEL CAWLEY
EASTERN ENTERPRISES
9 RIVERSIDE ROAD
WESTON, MA 02193
MICHAEL CAWLOY
8NEWHALLROAD
LYNNFJELD, MA 01940
MR ALAN D. CIRCEO DIRECTOR AC CRUISE
LINES, INC.
290 NORTHERN AVENUE
BOSTON, MA 02210
MR MATT CLARK, LAB DIRECTOR
EVERGREEN CONSTRUCTION CO, INC
34 WILLIAMS WAY
BFJT.TNGHAM, MA 02019
11-11
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PAULPCODINHA
70 FRIEND STREET
GLOUCESTER MA 01930
EDWARD CONNOLLY
INTERNATIONAL LONGSHOREMEN'S
ASSOCIATION
37 SOLEY STREET
CHARLESTOWN, MA 02129
DANIEL CONROY
INTERNATIONAL LONGSHOREMEN'S
ASSOCIATION
LOCAL 1066 183 "N" STREET
SOUTH BOSTON, MA 02127
MS. SHELL! COSTA
IB AY VIEW DRIVE
BREWSTER, MA 02631
MR. BRIAN J. COX
BOSTON LINE & SERVICE CO., INC.
1 BLACK FALCON AVENUE
BOSTON, MA 02110
DR PETER H. CRESSEY, CHANCELLOR
UNIVERSITY OF MASSACHUSETTS-
DARTMOUTH
OLD WESTPORT ROAD
NO. DARTMOUTH, MA 02747
RICK CUNNINGHAM
SALTWATER SPORTSMEN
77 FRANKLIN ST
BOSTON MA 02110
MR, STEVE DALTON
MOBIL OIL COORPORATION
MARINE TRANS DEPT
PO BOX 070116
STATEN ISLAND, NY 10307
MR. STEVEN C. DAVIS, PRESIDENT
RAC
INC
ONE FINANCIAL CENTER
BOSTON, MA 02111-2659
PHILLIP DAWES
BIOSAFE
10 FAWCETT ST.
CAMBRIDGE MA 02138
SHERYL DCOEENER
CAMBRIDGE INFORMATION GROUP
7200 WISCONSIN AVENUE SUITE 610
BETHESDA, MD 20814
MR. RODOLFO A. DE SOTOMAYOR
DOCK SUPERVISOR, EXXON COMPANY USA
52 BEACHAM STREET
EVERETT, MA 02149-5534
MS. EDITH DEANGELIS
388 MERIDIAN STREET
EAST BOSTON, MA 02128
MR. MIKE DECONINCK
MEDA
PO BOX 625 44 NORTH STREET
MATAPQSIT, MA 02379
MR. RUSSELL DECONTI, DIRECTOR
CENTER FOR COASTAL STUDIES
PO BOX 1036 59
COMMERCIAL STREET
PROVINCETOWN, MA 02657
MR. RICHARD DELANEY
UNIVERSITY OF MASSACHUSETTS-
BOSTON URBAN HARBORS INSTITUTE HARBOR
CAMPUS
BOSTON, MA 02125-3393
MARSHALL DENNIS
CORTELL ASSOCIATES
244 SECOND AVENUE
WALTHAM, MA 02154
MR RICHARD DENTREMONT
ICF KAISER ENGINEERING MA INC
190 TAFTS AVENUE
WINTHROP, MA 02152
MR. RALPH DEXTER, GENERAL MANAGER
MORAN SHIPPING AGENCIES, INC.
141 PEARL STREET
BOSTON, MA 02110
11-12
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MS. HARRIET DIAMOND
DIAMOND ENVIRONMENTAL ASSOCIATES
32 CHATHAM ROAD
NEWTON HIGHLANDS, MA 02161
PAULV.DOBIE
STEAMSHIP CLERK'S UNION
LOCAL 1066 LL.A. 11 MONUMENT STREET
CHARLESTOWN, MA 02129
MS.ANNDONNER
MOVE MASSACHUSETTS 2000
SUITE 628 294
WASHINGTON STREET
BOSTON, MA 02108
MR. MICHAEL F. DUARTE
BAY STATE TOWING
PIER 1 EAST BREMEN STREET
EAST BOSTON, MA 02128
DWIGHTDUNK
COLER AND COLANTONIO
20 POND PARK ROAD
HINGHAM, MA 02043
TIMDUNLAP
ECDC ENVIRONMENTAL
ONE WESTINGHOUSE PLAZA SUITE 200
HYDE PARK MA 02136
JOSEPH DUNN, PRESIDENT
NORTH SHORE HARBORMASTERS
ASSOCIATION
87 BARSTOW STREET
SALEM MA 01970
MAUREEN EDRIDGE
CENTER FOR MARINE CONSERVATION,
SUITE 500
1725 DESALES STREET, NW
WASHINGTON, DC 20036
ALEXANDER FERENT
BHLCOOP
287 K STREET
SOUTH BOSTON, MA 02127
THOMAS FITZGERALD
INTERNATIONAL LONGSHOREMEN'S
ASSOCIATION, LOCAL 1066
7PARSENLANE
BTT.T ERICA. MA 01821
MR. KEN FREEMAN
MORRISON KNUDSEN/INTERBETON/ JF WHITE
PO BOX 1905
BOSTON, MA 02205
MR. PAUL FRIDAY
CONCURRENT TECHNOLOGIES CORP
1450 SCALP AVENUE
JOHNSTOWN, PA 15904
ALFRED E. FRIZELLE
BOSTON SHIPPING ASSOCIATION, INC.
CHARLESTOWN NAVY YARD 33 THIRD
AVENUE, SUITE 1
BOSTON, MA 02129-4516
DAVID P. GALMAN
BOSTON TOWING & TRANSPORTATION
BOSTON HARBOR DOCKING PILOTS
36 NEW STREET
EAST BOSTON, MA 02128
PAUL GAUDES, MANAGER,
PORT OPERATIONS REGION DIRECORATE,
NORTH AMERICA NEDLLOYD LINES (U.S A.)
CORP
451D STREET SUITE 804A BOSTON MA 02210
MARTINA GAVIN
87 BELGRADE AVENUE
ROSLINDALE, MA 02131
MR.JOHNGEDDIE
8040 BELLAMAH CTNE
ALBUQUERQUE, NM87110
MR. DOUGLAS GIFFORD
58 CHARLES STREET
CAMBRIDGE, MA 02141
JAMES GOLDSTEIN
TELLOS INSTITUTE
11 ARLINGTON STREET
BOSTON, MA 02116
11-13
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DR.DIANE GOULD
MASSACHUSETTS BAYS PROGRAM
ROOM 2006 100
CAMBRIDGE STREET BOSTON, MA 02202
SANDRA GOULD
COURAGEOUS SAILING CENTER
1HRST AVENUE CHARLESTOWN NAVY YARD
CHARLESTOWN, MA 02129
ALEXGWEHNKEL
INNOVA. TECH ASSOC
11CAMELOT COURT #1A
BOSTON, MA 02135
MR WILLIAM HAGENZEKER
86 COURT ST.
AUGUSTA ME 04330
ROBRT F. HEFEERNAN, VICE PRESIDENT
NORTH SHORE RECYCLED FIBERS
53 JEFFERSON AVE. P.O. BOX 3007
SALEM MA 01970
MR. JOHN HEGARTY
60 MOSELEY STREET
DORCHESTER, MA 02125
MS INGEBORG HEGEMANN
THE BSC GROUP
425 SUMMER STREET
BOSTON, MA 02210
MR. FOREST HENDERSON
EAENGINEERING
2 COMMERCIAL STREET
SHARON, MA 02067
MR. THOMAS HILL
C/0 NEW ENGLAND HSHERIES MANAGE*
COUNCIL
27 FERRY STREET
GLOUCESTER, MA 01930
EDWARD HOLLJNGSHEAD
FAY, SPOTFORD & FORNAN, SUITE 920
22 PARK PLAZA
BOSTON, MA 02116
JEFFREY A. HOPKINS,
DIRECTOR OF SALES AND MARKETING
DECORATIVE SPECIALTIES INTERNATIONAL
1 CANAL STREET
SOUTH HADLEY MA 01075
WILLIAM P. HOROHOE, PRESIDENT
JOHN T. CLARK AND SON
BOSTON FISH PIER, WEST BUILDING SUITE 301
BOSTON MA 02210
MR. GARY HUNT
BPOJLCOMPNAY
41 LEE BURB ANK HIGHWAY
REVERE MA 02151
JENNIFER JONES
STRA, SUITE 1700
1100 WILSON BOULEVARD
ARLINGTON, V A 22209
DOUG JORDAN
12 OLD HILLS RD.
DENNIS MA 02638
MICHAEL KAHL
EASTERN ENTERPRISES
9 RIVERSIDE ROAD
WESTON, MA 02193
MR. KENNETH S. KAMLET
SEMMES, BOWEN AND SEMMES
250 WEST PRATT STREET
BALTIMORE, MD 21201
MR. PATRICK KEANEY
PIT ENVIRONMENTAL
1601TRAPELO ROAD
WALTHAM MA 02154
J.WILLIAM KENNEY
VULCAN/BOSTON, INC.
253 NORTHERN AVENUE SUITE 201
BOSTON, MA 02210
MR. RONALD KENNY
GLOBAL PETROLEUM CORP
140 LEE BURB ANK HIGHWAY
REVERE, MA 02151
11-14
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MS CAROLYN KELEY
BAY STATE CRUISE COMPANY
67 LONG WHARF
BOSTON, MA 02110
CAPTAIN CRAIG KINNEY
PO BOX 993
CONWAY, NH 03818
CAPTAIN ARTHUR M. KNIGHT
491 JERUSALEM ROAD
COHASSETT, MA 02025
MR. PAUL KRAYCH
DYNAMIC CORPORATION, SUITE 500 2275
RESEARCH BOULEVARD
ROCKVTT.T.F., MD 20850
NIKKUNCHUR,P£.
AECL ACCELERATORS
436B HAZELDEAN ROAD
KANATA ONTARIO, CANADA K1L1T9
MR. PAUL LAMB
EASTERN MINERALS INC.
37 MARGINAL STREET
CHELSEA MA 02150
WALTER B. LANDIN
OPERATIONS ENGINEER
BOSTON GAS COMPANY
201 RTVERMOOR STREET
BOSTON MA 02132
MR ARTHUR LANE
PEABODY & LANE, INC
ONE CONSTITUTION PLAZA
BOSTON, MA 02129
BETSILLATTIMER
11D SEA BREEZE LANE
NAHANT MA 01908-1547
STEVE LECCO
MCQUIRE GROUP
ONE COURT STREET
NEW BRITAIN, CT 06051
DAVID LEVEILLE
GLOUCESTER FISHERMAN'S WIVES
52 PERKINS STREET
GLOUCESTER, MA 01930
MS. VIVIEN LI
EXECUTIVE DIRECTOR
THE BOSTON HARBOR ASSOCIATION
SUITE 609
374 CONGRESS STREET
BOSTON, MA 02210
LARRY LIEBESMAN
250 WEST PRATT STREET
BALTIMORE, MD 21044
TOMLOGRANDE
GLOUCESTER FISHERMAN'S WIVES
22R DALE AVENUE
GLOUCESTER, MA 01930
EDWARD LONERGAN
89 BASS POINT ROAD
NAHANT MA 01908
VERNONB.LONG
22 BRIDGE ST, UNIT #1
CONCORD NH
MR. WILLIAM LONGFTF.TD
201 WEBSTER ST.
EAST BOSTON MA 02128
MR. KENETH MACGRIOR
PURCELL ASSOCIATES
90 NATIONAL DRIVE
GLASTONBURY CT 06033
MR. ROBERT MAGNUSSON
WEHRAN ENGINEERING
6 RIVERSIDE DRIVE
ANDOVER MA 01810
MR. EDWARD MAHONEY
193 CAMP STREET F4
WEST YARMOUTH, MA 02673
MR MARK MAHONEY
1021 MAIN ST
WINCHESTER MA 01890
11-15
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KEVHSTMANNING
INTERNATIONAL LONGSHOREMEN'S
ASSOCIATION, LOCAL 800
507 HOGG MEMORIAL DRIVE
WHITMAN, MA 02382
J.MARALDO
WASTE MANANGEMENT SPECIAL WASTE
56 ROLAND STREET
CHARLESTOWN, MA 02129
CHRIS MARCHESI
GROUNDWATER, INC.
415 KHUNGWORTH ROAD
fflGGANUMCT 06441
MR. PHILIP K. MCCARTHY
REGIONAL OPERATIONS MANAGER
COASTAL OILNEWENGLAND, INC
222 LEEBURBANK HIGHWAY
REVERE, MA 02151-4096
MR. IAN MCDERMOTT
C CORE MEMORIAL UNIVERSITY
ST JOHNS NEWFOUNDLAND CANADA
A1B3X5
MR. TONY MCDONALD
AAPA
1010 DUKE STREET
ALEXANDRIA, VA 22314
MR JACK MCGINNESS, PRESIDENT
BOSTON HARBOR LOBSTERMEN'S ASSOC.
2 SAGAMORE TERRACE
HULL MA 02045
SUZANNE MCGRADY
SWAMPSCOTT REPORTER
40 SOUTH STREET SUITE 100
MARBLEHEAD MA 01945
MS. MELANIE MCGUIRE
ALCEON CORPORATION
2067 MASSACHUSETTS AVE.
CAMBRIDGE MA 02140
ROBERT MCKEON
CAMBRIDGE CO.
5515TH AVE. SUITE 501
NEWYORK NY 01107
WILLIAM R. MCNAMARA
INTERNATIONAL VICE PRESIDENT
INTERNATIONAL LONGSHOREMEN'S
ASSOCIATION
399 POND STREET UNIT D-6
BRAINTREE, MA 02184
MATTHEW A. MERKEL
P&O CONTAINERS, LTD.
THE BOSTON HSH PIER, WEST BUILDING 2
SUITE 305
BOSTON MA 02210
KEVIN MILLER
ENVIRONMENTAL PROTECTION SYSTEMS
PO BOX 3219
BROCKTON, MA 02404
WILLIAM MILLER
ILA
222 WILSON AVENUE
QUINCY, MA
FRANK MIRARCHI
67 CREPT MAN DRIVE
SCITUATE MA 02066
DR. SCOTT C. MOHR
CHEMISTRY DEPARTMENT BOSTON
UNIVERSITY 590 COMMONWEALTH AVE
BOSTON MA 02215
DR. LIN MORGENSTERN
PRINCIPAL ENVIRONMENTAL PLANNER
BOSTON EDISON CO.
800 BOYLSTON STREET P 292
BOSTON, MA 02199
MR. ANDREW M. MORRISON
PROLEREED NEW ENGLAND
P.O. BOX 0048
EVERETT MA 02149
SAIC
221 3RD STREET
NEWPORT RI02840
11-16
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MR & MRS PALMER
ANCHOR COTTAGES
201 NORTH SHORE BOULEVARD
EAST SANDWICH, MA 02563
CAPTAIN STEVE PALMER
BILL BLACK SHIPPING AGENCY
900 E FIRST STREET
SOUTH BOSTON, MA 02127
GERARD PARTEE
INTERNATIONAL LONGSHOREMEN'S
ASSOCIATION B/A, LOCAL 805
21SIVAN AVENUE
EAST BOSTON, MA 02128
MARGE PATTERSON
TRANSPORTATION ADMINISTRATOR
REXHAM.INC.
P.O. BOX 811
SOUTH HADLEY MA 01075-0811
EUGENEPECK
15 PARK STREET
BOSTON, MA 02136
CAPT A. ROSS POPE
PATTERSON WYLDE & CO INC
WEST BUILDING 2 - SUITE 305
BOSTON FISH PIER
BOSTON, MA 02210
MR. ARV POSHKUS
19 CAMDEN STREET
STOUGHTON, MA 02072
D AVID E. POWELL
C. H. POWELL COMPANY
1 INTERCONTINENTAL WAY
PEABODY MA 01960
JOHNW. RAGOBA.
PRESIDENT, INTERNATIONAL
LONGSHOREMEN'S ASSOCIATION
LOCA L 1604 26 SUNSET DRIVE
WAKEFffiLD, MA
MR, WILLIE RICH
DISTRIGAS
18 ROVER STREET
EVERETT MA 02149
TERRY RIGHAN
CTPS
10 PARK PLAZA, ROOM 2160
BOSTON MA 02116
WILLIAM E. ROBINSON
MALOBSTERMAN-S ASSOCIATION
7 HOUSTON AVENUE
SAUGUS, MA 01906
JOHNW.ROGO
26 SUNSET DRIVE
WAKEFIELDMA
MR. JOHN ROSTANZO
BOSTON EDISON
PRODUCTION ENGINEERING DEPT.
800 BOYLSTON STREET
BOSTON MA 02199
ROSERUGGERIO
19 SWIFT TERRACE
EAST BOSTON, MA 02128
MR. ROBERT & MICHAEL RUSSO
63 BARNES AVENUE
EAST BOSTON, MA 02128
ANGELA SANFILIPPO
GLOUCESTER FISHERMAN'S WIVES
3 BEAUFORT AVENUE
GLOUCESTER, MA 01930
JEFF SEGAL
7 WEBSTER AVE.
EAST BOSTON MA 02128
DERRICK A. SHIRLEY
PORT MANAGER
SEA-LAND SERVICE, INC.
BERTH n P.W. CONLEY MARINE FACILITY
SOUTH BOSTON MA 02127
MR. ROBERT E. SILVA
TERMINAL MANAGER GULF OIL
281 EASTERN AVENUE, PO BOX 188
CHELSEA, MA 02150-0188
11-17
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MR.JOHNSMOLAK
WARNER AND STACKPOLE
75 STATESTREET
BOSTON MA 02109
MR, JACK SOBEL DIRECTOR,
HABITAT CONSERVATION CENTER FOR
MARINE CONSERVATION
1725 DESALES STREET, NW
WASHINGTON, DC 20036
MR. SAM SOFER
SRE INCORPORATED
158 PRINCETON ST.
NUTLEY NT 07110
MS KATHLEENFINIGAN STONE
SR ENVIRONMENTAL ENGINEER
BOSTON EDISON CO.
800 BOYLSTON STREET P 292
BOSTON, MA 02199
MR. GEORGE STRAWAL
2747 RICHMOND TERRACE
STATEN ISLAND, NY 10303
JAY SULLIVAN
201 ROVER STREET
EVERETT, MA 02149
MR. RAY SUTHERLAND
29 FRIEND STREET
GLOUCESTER, MA 01930
MR. PETER TAYLOR
ATLANTIC FUELS MARKETING CORP
11 BROADWAY
CHELSEA, MA 02150
MR. HALSEY TAYLOR
901 NAVIGATION BLVD
CORPUS CHRIST! TX 78407
CHASE TAYLOR
593 CENTRE STREET
JAMAICA PLAIN MA 02130
MR. ANTHONY TERMINE
THE GILLETTE COMPANY
1 GILLETTE PARK
BOSTON, MA 02127-1096
MR. RICHARD F. THOMAS, PE
GAHAGAN & BRYANT ASSOCIATES, INC.
Ill MARKET PLACE SUITE 1001
BALTIMORE, MD 21202
JIMTRENZ
TERRANE REMEDIATION, INC.
347 MT. BLUE ST.
NORWELL MA 02061
MR. BRUCE TRIPP
WOODS HOLE OCEANOGRAPfflC INSTITUTE
COASTAL RESEARCH CENTER
WOODS HOLE, MA 02543
FRANVALENTI
F. M. VALENTI, INCORPORATED AND
ASSOCIATES
1 SAUNDERS LEDGE
NAHANT MA 01908-1692
MR. RICHARD VARNEY
40 DRAPER AVE.
HULL MA 02045-2233
MR. GERRY VELLENEUVE
763 THIRD AVENUE
BERLIN, NH 03570
DAVID VINE
253 LOW STREET
NEWBURYPORT, MA 01950
DR. MICHAEL J. WADE
PRINCIPAL SCIENTIST
WADE RESEARCH, INC
110 HOLLY ROAD
MARSHFIELD, MA 02050
MR. JONATHAN C WALES
BOSTON TOWING & TRANSPORTATION
36 NEW STREET
EAST BOSTON, MA 02128
DR. GORDON T. WALLACE
ENVIRONMENTAL SCIENCES PROGRAM
UNIVERSITY OF MASSACHUSETTS AT BOSTON
BOSTON MA 02125-2293
11-18
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MICHAEL R. WALSH
REGIONAL GENERAL MANAGER
MAERSK INC.
SUITE 260, EDGEWATER PARK
401 EDGEWATER PLACE
WAKEFEELD MA 01880
MARKWEISSMAN
NEW ENGLAND CONST. CONS. ASSOC.
MARINE FISHERIES COMMISSION
270 PELHAM ISLAND ROAD
WAYLAND, MA 01778
JAYWENNEMER
MANOMET OBSERVATORY
57 JUSTINE AVENUE
PLYMOUTH, MA 02360
C APT ARTHUR WHITTEMORE
BOSTON PILOTS
PIER 1 SOUTH BREMEN STREET
EAST BOSTON, MA 02128
MR. JACK WIGGINS
UNIVERSITY OF MASSACHUSETTS-
BOSTON URBAN HARBORS INSTITUTE
HARBOR CAMPUS
BOSTON, MA 02125
OSCAR WEJKJNS
WASTE MANAGEMENT INC.
56 ROLAND STREET
CHARLESTOWN, MA 02129
NANCY WILSON
106 POND ST
NAHANT MA 01908
COLLEEN WOOD
CETACEAN RESEARCH UNIT
19 BROOK STREET
MANCHESTER, MA 01944
MR. BRUCE YOUNG
NORTHEAST PETROLEUM, INC
72 CHERRY HELL DRIVE
BEVERLY, MA 01915
LOUIS ZAPPffiRI
BOSTON SAND AND GRAVEL
201 ROVER STREET
EVERETT, MA
RACHEL ZOLL
SALEM EVENING NEWS
23 CHESTNUT ST
SALEM MA 01970
11-19
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Chapter Twelve: Index
Advisory Committee . 1-10,3-4,4-33,4-34,5-30
Alternatives. . . .1-2,1-10 thru 13, 1-15, 1-16,2-1,2-3,2-4,2-9,2-10, 2-15,2-16, 3-1 thru 4
3-6, 3-12 thru 3-14, 3-16 thru 19, 3-37, 4-2, 4-8 thru 12, 4-21, 4-27 thru 29, 4-33
4-39,4-40, 5-28, 6-2, 6-13, 6-15, 6-16, 7-5, 8-3
Amstar 3-16, 3-17, 3-23,4-9, 4-10, 4-30, 4-32,4-36 thru 38, 4-40
AnadromousFish 3-19,3-37,4-18,4-22,5-12,5-18,5-21,6-14,6-15,8-4
Barge Traffic 3-19, 6-10, 8-4
Beneficial Use 3-4,3-5,3-20,3-24,3-29,3-33,3-36,5-4,6-11,8-7
Benthos 4-12,4-15,4-22,8-4
Birds 3-15, 4-27, 6-15
Boston Lightship3-6, 3-19, 3-20, 3-26, 3-27,4-9,4-10,4-13 thru 15,4-18 thru 20, 4-23,4-24
4-26 thru 38, 4-40
Cabot Paint 3-16,3-17,3-23,4-9,4-10,4-32,4-36 thru 38,4-40
Capping. . 1-8,1-11,1-12, 1-14, 1-16,2-7,2-13 thru 16, 3-3 thru 6, 3-14, 3-15, 3-17 thru 20
3-24,3-26,3-27,3-35, 3-38, 3-39,4-7,4-8,4-12,4-14,4-15,4-19, 4-28, 4-32,4-33
4-39, 5-3, 5-9, 5-13, 5-17, 5-18, 5-29, 5-30, 6-12, 6-13, 7-3, 8-3, 8-6, 8-12
Chelsea Creek . . 1-4,1-5, 1-7,1-8, 2-1 thru 4,2-6 thru 8,2-10,2-11,3-18, 3-34, 3-38, 3-39
4-9, 5-1, 5-2, 5-8, 5-11, 5-13 thru 15, 5-17, 5-19, 5-20, 5-26, 6-1, 6-5, 6-7, 8-1, 8-8
8-10,8-13,8-14
Circulation 2-11, 7-3, 8-11, 8-12
Clams 4-13,4-21,4-22, 4-25, 6-15
Coastal Zone Management Act 7-5
Conley Terminal 2-5, 6-1
Contaminated Sedimenfls-11,2-14,3-6, 3-17,3-32,4-12,4-24,4-26,4-29, 5-5, 6-12, 6-16, 8-7
Costs . 1-5, 1-6, 1-8,1-11, 1-13, 2-2,2-3, 2-8, 2-10,2-13, 3-3, 3-10, 3-21 thru 27, 3-32, 3-38
3-39, 4-37 thru 39
Cumulative Impacts 1-9,3-1,6-1,6-9,6-10,8-2,8-5
Currents 2-11,3-17, 3-18,4-18 thru 21,4-23,4-27, 4-29, 5-1, 6-4
Designated Port Area 4-30, 6-2
Dissolved Oxygen 6-1, 8-6
Dredging . 1-1 thru 9, 1-11 thru 16, 2-1 thru 14, 2-16,2-17, 3-1 thru 5, 3-7, 3-10, 3-12, 3-14,
3-15, 3-17 thru 19, 3-21 thru 26, 3-30, 3-33 thru 3-39,4-4,4-5,4-7, 4-9 thru 11, 4-13
4-15 thru 17, 4-21, 4-22, 4-26, 4-28,4-29, 4-33,4-34,4-36,4-38 thru 41, 5-1 thru 5-30
6-1 thru 14, 7-1 thru 5, 8-1 thru 14
12-1
-------
Energy ............................ 1-6,3-28,3-34,4-14,6-15,8-3
Environmental Consequences ..................... • ......... 3-20
Environmental Bucket ............ 1-14,5-12,5-13,6-3,6-4,6-12,8-7,8-8,8-13
Everett . . . 3-14, 3-15, 3-22, 3-25, 3-26, 4-2, 4-5 thru 8, 4-30, 4-33 thru 35, 4-37, 4-40, 7-1
ing . . 3.4, 3-5, 3-17, 3-23 thru 25, 3-34, 4-9 thru 1 1, 4-13, 4-15, 4-28, 4-29, 4-37, 4-41
* 5-18,5-21,7-4,8-4,8-14
KshRun
Historic ...................................... 3'5' 5'1' 6'6
Hydrology ...................................... 8'9> 8'12
In-Channel Sites . . 3-19, 4-9, 4-12 thru 14, 4-22, 4-27, 4-29, 4-30, 4-37, 4-39 thru 41, 5-17
Industrial Development .................................
7-4
Little Mystic Channel. . . . 3-16, 3-17,3-23,3-25,3-35,4-9,4-11,4-30,4-32,4-35 thru 41
5-13, 5-14, 6-2, 6-15, 6-16, 8-4
Lobsters ' 3-12'4-23
Main Ship Channell-3,1-8,2-2 thru 7,2-11 thru 13,3-27,3-34, 5-1, 5-13, 5-16, 6-1, 6-4, 6-14
8-1 thru 3
Mammals 6-6,6-8,8-14
MarineMammals 6"6> 6"8
Massachusetts Port Authority (Massport) 1-1,7-1,8-2
Meisburger 2 . . 1-12,1-14, 3-18, 3-19, 3-26,4-9,4-13, 4-14,4-18 thru 20,4-23,4-24, 4-27
4-31 thru 38
Meisburger 7. . . .3-24,3-26,4-9,4-13 thru 15, 4-18 thru 20,4-23,4-24,4-27, 4-31thru 33
- 4-35 thru 38
Mitigation. 1-10,1-16,3-4,3-19,3-33,4-32,4-37,5-16,5-20,5-23,5-24,6-1,6-3
6-11 thru 16, 7-1, 8-1, 8-4 thru 8-7, 8-14
Moran Terminal 1-4,2-6,5-10,6-1,6-9
Mystic Piers 1-8,2-6,3-17, 3-23,3-25,4-5,4-9 thru 11,4-30,4-32,4-36 thru 38,
4-40, 6-2, 8-2
Mystic River 1-3,1-4,1-8,2-1,2-3 thru 5, 2-7, 2-10,2-11,3-18, 3-19, 3-25, 3-26,3-38, 3-39
4.9 4.17,4-18, 4-22,4-30,4-32,4-33,4-36,4-38,4-40,4-41, 5-1, 5-2, 5-8, 5-11, 5-17
5-19, 5-21, 5-26, 5-28, 6-1, 6-2, 6-5, 6-7, 6-14, 6-15, 8-1, 8-3, 8-4, 8-8, 8-10, 8-13, 8-14
Navigation Improvement Project 1-3,1-8,2-2,2-4,2-8,3-2,3-38,6-1,6-6,6-10
Noise 4-4,4-5,4-7,4-8, 4-33, 5-2, 5-29, 5-30, 6-1, 6-6 thru 8, 8-4
President Roads 1-4,1-8,2-3,2-6,2-7,2-11,2-12,8-2
Reserved Channel. 1-3,1-4,1-8,2-1,2-3 thru 5,2-7,2-8,2-10, 2-11, 3-16, 3-17, 3-23 thru 25
12-2
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3-35,4-9, 4-13,4-20, 4-29,4-32, 4-35 thru 38, 4-40, 5-1, 5-8, 5-11, 5-13 thru 16, 5-19
6-1, 6-10, 6-14, 8-1
Revere Sugar . 1-8, 2-6, 3-16, 3-17, 3-23, 3-25, 4-5,4-9, 4-10,4-30,4-32, 4-36 thru 38, 4-40
6-2, 8-2
RockBlasting ; 2-4
Runoff 2-2, 3-14, 4-4, 5-26, 8-f
SaltMarshes 7-3, 8-11
Secondary Impacts 6-1, 6-8, 8-5
Sediments 1-11 thru 13,2-2,2-11,2-12,2-14,2-15,3-2, 3-3, 3-6, 3-12
3-13,3-15 thru 20, 3-22, 3-23, 3-26 thru 3-29,3-32, 3-33, 3-35, 3-39, 4-5
4-9 thru 18,4-20 thru 29, 5-1 thru 5, 5-8, 5-12, 5-13, 5-18, 5-21, 5-24
5-26, 5-27, 5-30, 6-1, 6-4, 6-5, 6-12, 6-16, 8-7, 8-13
Sewage Treatment Plant 6-11
Shellfish 3-5,3-37,3-39,4-7,6-3,6-14,6-15,7-2,7-3,8-10,8-11
Solid Waste 2-15,3-8,3-9,3-16,3-35,3-36,4-3,4-5,4-6,4-31
Spectacle Island CAD. ..... 1-14,2-14,3-18,3-19,3-24 thru 26,3-34,4-9,4-12 thru 15
4-19,4-20, 4-23, 4-28, 4-32, 4-39
Squantum Point 3-14, 3-15,3-22, 3-23,3-25, 3-26, 4-2,4-5 thru 8,4-30,4-33,4-35
4-37 thru 41
Suspended Sediments 4-16,4-21
Threatened and Endangered Species 3-20,6-6, 6-7
Treatment Technology 3-31, 3-38
Utilities 2-6, 5-11
Water Quality Impacts 1-15,2-15,3-13,3-15,3-17,3-24,4-4,4-16,4-17,8-5
Wetlands 1-9,1-16, 3-4,3-7, 3-14, 3-37,4-1, 4-6, 4-8,4-30, 7-1, 7-2, 7-4, 8-7, 8-8
Wildlife 4-6,4-7,4-41,6-6,6-15,8-14
Winthrop Harbor 3-18,3-24
Woburn. . .3-11, 3-14, 3-15, 3-23,3-26, 4-2, 4-5 thru 8,4-30,4-32 thru 35, 4-37, 4-38,4-40
Wrentham. . 3-12,3-14,3-15, 3-22,3-23, 3-25, 3-26,4-1,4-2,4-5 thru 8,4-30,4-32 thru 35
4-37 thru 40
12-3
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ATTACHMENT 1:
AFFECTED ENVIRONMENT AND ENVIRONMENTAL
CONSEQUENCES EVALUATED FOR POTENTIAL
DREDGING AND DISPOSAL SITES
TABLE OF CONTENTS
PAGE
1.0 INTRODUCTION Al-1
2.0 ENVIRONMENTAL EVALUATION: DISPOSAL SITES Al-3
2.1 SITE EVALUATIONS: LAND-BASED COASTAL SITES Al-5
2.1.1 Squantum Point (QUI-03) Al-5
2.1.1.1 Existing Conditions Al-5
2.1.1.2 Environmental Consequences Al-15
2.1.2 Everett (EVR-04) Al-20
2.1.2.1 Existing Conditions Al-20
2.1-2.2 Environmental Consequences Al-25
2.2 SITE EVALUATIONS: LAND-BASED INLAND SITES Al-28
2.2.1 Woburn (WOB-11) ; Al-28
2.2.1.1 Existing Conditions Al-29
2.2.1.2 Environmental Consequences Al-36
2.2.2 Wrentham (WREN-495) Al-40
2.2.2.1 Existing Conditions Al-40
2.2.2.2 Environmental Consequences Al-48
2.2.3 Landfill Sites - An Overview Al-53
2.2.3.1 Existing Conditions Al-54
2.2.3.2 Environmental Consequences Al-56
Al-i
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PAGE
2.3 SHE EVALUATIONS: NEARSHORE AQUATIC SITES Al-58
2.3.1 Existing Conditions Al-58
2.3.1.1 Mystic Piers (Massport Piers 49 & 50) Al-58
2.3.1.2 Revere Sugar A1-65
2.3.1.3 Amstar A1'71
2.3.1.4 Cabot Paint Al-76
2.3.1.5 Little Mystic Channel Al-81
2.3.1.6 Reserved Channel Al-87
2.3.2 Environmental Consequences of Use of Shoreline Sites for Dredged
Material Disposal A1'94
2.4 SITE EVALUATIONS: IN-CHANNEL AREAS AND BORROW PITS . Al-99
2.4.1 Existing Conditions • Al-99
2.4.1.1 In-Channel Areas Al-99
2.4.1.2 Spectacle Island Confined Aquatic Disposal (CAD) . Al-99
2.4.1.3 Meisburger Sites 2 and 7 Al-106
2.4.2 Environmental Consequences of the use of In-Channel and Borrow
Pit Sites for Dredged Material Disposal Al-114
2.5 SITE EVALUATIONS: SUBAQUEOUS AREAS Al-135
2.5.1 Existing Conditions Al-135
2.5.1.1 Subaqueous Containment Site B (Subaq B) Al-135
2.5.1.2 Subaqueous Containment Site E (Subaq E) Al-141
2.5.2 Environmental Consequences of using Subaqueous Containment
Sites for Dredged Material Disposal Al-145
2.6 SITE EVALUATIONS: EXISTING AQUATIC DISPOSAL SITES . . . Al-157
2.6.1 Massachusetts Bay Disposal Site (MBDS) . Al-157
2.6.1.1 Existing Conditions Al-157
2.6.1.2 Environmental Consequences Al-163
2.6.2 Boston Lightship Disposal Site (BLDS) Al-168
2.6.2.1 Existing Conditions Al-168
2.6.2.2 Environmental Consequences Al-172
Al-ii
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PAGE
3.0 ENVIRONMENTAL EVALUATION - DREDGING SITES Al-177
3.1 OTHER PROJECT CONSIDERATIONS Al-177
3.2 DREDGING AREAS - ENVIRONMENTAL RESOURCES Al-178
3.2.1 Water Quality Al-178
3.2.2 Sediment Characteristics Al-182
3.2.3 Biological Resources '. Al-184
4.0
LITERATURE CITED Al-189
Al-iii
-------
LIST OF FIGURES
Al-1. General locations of short-listed disposal site alternatives
•
Al-2. Site map for potential disposal site, Quincy-03 (Squantum Point)
Al-3. Site map for potential disposal site, Everett
Al-4. Site map for potential disposal site, Woburn-11
Al-5. Site map for potential disposal site, Wrentham-495
Al-6. Site map for the Plainville Landfill site
Al-7. Site map for the Fitchburg/Westminster Landfill site
Al-8. Site map for BFI Northern Disposal Inc. (E. Bridgewater) Landfill site
Al-9. Site map for Mystic Piers site
Al-10. Site map for Revere Sugar site
A1-1L Site map for Amstar site
Al-12. Site map for Cabot Paint site
Al-13. Site map for Little Mystic Channel site
Al-14. Site map for Reserved Channel site
Al-15. Site map for Spectacle Island CAD site
Al-16. Site map for Meisburger 2 site
Al-17. Site map for Meisburger 7 site
Al-18. Site map for potential disposal site, Subaqueous-B
i
Al-19. Site map for potential disposal site, Subaqueous-E
Al-20. Site map for potential disposal site, Winthrop Harbor
Al-21. Site map for Boston Lightship and MBDS sites
Al-22. Prohibited and restricted clam beds in Boston Harbor
Al-iv
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Al-14. RESULTS OF POLLUTANT TRANSPORT MODELLING FORIN-CHANNEL
DISPOSAL SITES
Al-15. RESULTS OF POLLUTANT TRANSPORT MODELLING AT SPECTACLE
ISLAND CAD
Al-16 SEDIMENT CHARACTERISTICS IN VICINITY OF PROPOSED
SUBAQUEOUS CONTAINMENT SITES B AND E AND WINTHROP
HARBOR CONTAINMENT SITE
Al-17. RESULTS OF POLLUTANT TRANSPORT MODELLING FORIN-CHANNEL
DISPOSAL SITES
Al-18. RESULTS OF POLLUTANT TRANSPORT MODELLING AT SUBAQUEOUS E.
Al-19 MAXIMUM CONCENTRATION (mgA) OF COPPER AND SILT/CLAY IN THE
WATER STRATIFIED COLUMN AT THE BOSTON LIGHT SHIP DISPOSAL SITE
UNDER SUMMER CONDITIONS ESTIMATED BY THE ADAM'S MODEL FOUR
HOURS AFTER A SINGLE DUMP OF 2,000 CU. YDS.
Al-20. UTILITIES LOCATED WITHIN TRIBUTARIES PROPOSED FOR DEEPENING.
Al-21 AVERAGE CONCENTRATION OF TOTAL ORGANIC CARBON AND TOTAL
PETROLEUM HYDROCARBONS. MASSPORT DREDGING PROJECT.
Al-22 COMPARISON OF AVERAGE LEAD AND CHROMIUM CONCENTRATIONS
(MG/L) WITH MASSACHUSETTS DEP BULK SOIL CONCENTRATIONS (MG/L)
FOR TCLP ANALYSIS. MASSPORT DREDGING PROJECT.
Al-23. CONCENTRATION OF SODIUM AND CHLORIDE FOR MASSPORT DREDGING
PROJECT.
Al-vi
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LIST OF TABLES
AM. LANDFILL CHARACTERISTICS
Al-2.
Al-3.
ESTIMATED ABUNDANCE (NO./m2) OF BENTHIC INFAUNA (RETAINED
ON A 0.5 mm MESH SIEVE) COLLECTED BY 0.023 m2 PONAR GRAB
FROM PROPOSED DISPOSAL SITES IN BOSTON HARBOR, APRIL 28-29,
1993
MEAN ABUNDANCE (NO./m3) BY HABITAT OF BENTHIC INFAUNA
RETAINED 9N A 0.5mm-MESH SIEVE COLLECTED FROM INNER
HARBOR LOCATIONS, OCTOBER 1994
Al-4. STANDARDIZED MEAN CATCH PER UNIT EFFORT (CATCH PER 20
MINUTE TRAWL) BY STATION IN BOSTON HARBOR AND
MASSACHUSETTS BAY, OCTOBER 1994
Al-5. REPRESENTATIVE FINFISH SPECIES LIST, BOSTON INNER AND OUTER
HARBOR
Al-6. STANDARDIZED CATCH PER UNIT EFFORT (FISH PER 24-HOUR SET)
IN GILL NET COLLECTIONS FROM BOSTON HARBOR AND
MASSACHUSETTS BAY, OCTOBER 1994
Al-7. CATCH PER UNIT EFFORT (NUMBER/TRAP-DAY) BY SEX FOR
SUBLEGAL AND LEGAL SIZED LOBSTERS CAPTURED IN BOSTON
HARBOR, OCTOBER 1994
Al-8. SHORELINE SITE FOOTPRINT
Al-9. SEDIMENT CHARACTERISTICS IN THE VICINITY OF POTENTIAL
DISPOSAL SITE EAST OF SPECTACLE ISLAND, 1988a
Al-10. MEAN ABUNDANCE (NO./m3) BY HABITAT OF BENTHIC INFAUNA
RETAINED ON A 0.5mm-MESH SIEVE COLLECTED FROM OUTER
BOSTON HARBOR LOCATIONS, OCTOBER 1994
Al-11. MEAN ABUNDANCE (NO./m2) BY HABITAT OF BENTHIC INFAUNA
RETAINED ON A 0.5mm-MESH SIEVE COLLECTED FROM OFFSHORE
LOCATIONS, OCTOBER 1994
Al-12. DOMINANT FISH SPECffiSa AND LOBSTERS IN TRAWLS CONDUCTED
IN AN AREA JUST WESTb OF THE MWRA PROPOSED OUTFALL BY
MASSACHUSETTS DIVISION OF MARINE FISHERIES, 1991-92
Al-13. MIXING ZONES FOR DISPOSAL AT ESf-CHANNEL LOCATIONS
Al-v
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ATTACHMENT 1:
AFFECTED ENVIRONMENT AND ENVIRONMENTAL CONSEQUENCES EVALUA-
TION AT POTENTIAL DREDGING AND DISPOSAL SITES
1.0
INTRODUCTION
The purpose of this Affected Environment and Environmental Consequences Evalua-
tion is to provide more detailed descriptions of dredging sites and potential disposal sites, as
summarized in Sections 2.0, 3.0 and 4.0 of this Environmental Impact Report/Statement (EIR/S).
Described herein are the baseline environmental conditions, proposed site uses and potential envi-
ronmental consequences from dredging or disposal at each site. This evaluation is designed to
provide a description of both the "existing conditions" and "environmental consequences" at the
potential sites, in accordance with the MEPA EIR and Federal EIS guidelines.
Although the full project, in its entirety, is sponsored by Massport, the dredging
activities (and sites) are broken down into two components:
1)
2)
Federal Project: This includes deepening portions of the federal channels to 40 feet
including areas within the:
*• Mystic River
*• Chelsea Creek (to-38 feet MLW)
* Inner Confluence
> Main Ship Channel
> Reserved Channel
This portion of the project is being administered by the Army Corps of Engineers-
New England Division (ACOE NED).
Non-federal Project: This includes the dredging of several berth areas throughout
the Inner Harbor, Mystic River, Chelsea Creek, and the Reserved Channel. This
portion of the project is administered by Massport and includes the following sites:
*• Prolerized
> Distrigas
+ Moran
»• Mystic Piers
> Eastern Minerals
* Gulf Oil
»• North Jetty
*• Army Base
> Boston Edison Intake
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>• Boston Edison Barge Berth
>• Conley
The project is described in Section 2.1, Volume 1 of the EIR/S. This evaluation focuses on the
environmental conditions and impacts at the disposal sites.
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2.0 ENVIRONMENTAL EVALUATION:
DISPOSAL SITES
As part of this EIR/S process, an extensive site screening process (Section 3.0 in
EIR/S) was undertaken to identify potential disposal sites for this project's dredged material. As
a result of this process, 24 candidate sites were deemed potentially suitable for material disposal.
They are grouped according to site type as follows:
Land-Based Coastal Sites
Squantum Point (QUI-03)
Everett (EVR-04)
Land-Based Inland Sites
Woburn(WOB-ll)
Wrentham (WREN-495)
Plainville Sanitary Landfill
Fitchburg/Westminster Sanitary Landfill
BFI-Northern Disposal, Inc. (East
Bridgewater)
Aquatic Sites
In-Channel Disposal (3 sites)
Subaqueous Containment Site B
Subaqueous Containment Site E
Nearshore Aquatic Sites
Mystic Piers (Massport 49 & 50)
Revere Sugar
Amstar
Cabot Paint
Little Mystic Channel
Reserved Channel
Borrow Pit Sites
Spectacle Island Confined Aquatic
Disposal (CAD)
Meisburger Sites 2 and 7
Existing Open Water Sites
Massachusetts Bay Disposal Site
Boston Lightship Disposal Site
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Locations of these potential sites are shown in Figure Al-1 and presented in more detail on
figures contained in the following sections. The sites are described generally in the order given
above; their order has no bearing on their status as an acceptable or preferred alternative.
The environmental evaluation process included a review of previous environmental
studies and reports followed by site investigations to supplement and fill primary data gaps. Field
groups comprised senior scientists in disciplines such as wetland ecology, wildlife ecology, marine
ecology, estuarine ecology, water quality planning, and engineers experienced in environmental
issues at landfills, materials disposal, site drainage, and site planning. During the in-field site
investigations, these experts recorded their findings for baseline environmental conditions for each
candidate site.
This evaluation examines impacts to each potentially sensitive resource at each of the
candidate sites. Summaries of project impacts at each candidate site are presented in Section 3.0
oftheEIR/S.
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Squantum Point (QUI-03)
2.1 SITE EVALUATIONS;
LAND-BASED COASTAL SITES
2.1.1
Squantum Point (OUI-03)
2.1.1.1 Existing Conditions
The Squantum Point site is located at the tip of Squantum Point in the City of Quincy
(Figure Al-2). Formerly the Squantum Naval Air Station, the site is 44 acres in total area,
however the eastern portion of the site has been developed into a staging point for the Deer Island
wastewater treatment facility. The available area for the BHNIP containment facility is
approximately 32 acres. The 100-year floodplain is 11 feet above MSL.
GEOLOGY/SOILS
The site appears to consist of historic tidelands that were filled for the construction
of a small naval air station. The area is generally flat and surrounded on the shoreline perimeter
by an eroded and dilapidated metal and concrete seawall. Soils in the project area are primarily
Udorthents, which are classified as areas filled with excavated materials (SCS 1989a). Thickness
of material is generally six feet or more, although the actual depth of fill at this site is unknown.
The type of bedrock underlying the site can only be inferred since no outcrops of
bedrock are evident. Based on the mapping by Kaye (1980) this area may be underlain by
conglomerate or by tuffaceous sediments. Depth to bedrock is unknown.
HYDROLOGY/WATER QUALITY
The hydrology of the site is not fully understood and is complicated by remains of
the old airport's storm drain system (observed during site walks by project staff in November
1990 and May 1993). After a heavy rainstorm, water was observed in small pools in the upland
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Squantum Point (QUI-03)
i
j
areas, while the wetland did not appear to be storing any runoff. Closer observation revealed a
graded storm drain on the edge of the wetland and an outfall pipe to Dorchester Bay that, at that
time, was clearly discharging water. It is not known whether the wetland was the sole source of
this storm water flow or if other storm drams contributed as well. Water in the wetland drain was
later observed to have reversed direction, flowing back into the wetland.. This indicates that the
wetland area is hydrologically connected to Dorchester Bay and influenced by tides, although the
wetland plant community reflects only mildly brackish conditions. The erosion behind the
decayed seawall indicates that overland flow to the bay does occur, although the erosion is in part
due to tide and wave action.
No information concerning groundwater resources at this site was available. However,
groundwater appears strongly influenced by tides and could be highly saline. Any groundwater
at this site would not be suitable for public water supply.
The Neponset River and Dorchester Bay are both classified as SB by the Massachu-
setts Department of Environmental Protection (MADEP), in the surface water regulations (314
CMR 4.00). This classification protects saline water bodies for the following uses: propagation
of fish and aquatic life and wildlife, primary and secondary contact recreation, and shellfish
harvesting with depuration. Abundant shellfish beds are present in the tidal flats off Squantum
Point as noted during a site visit in October 1990. However, as these shellfish cannot be reliably
depurated, Massachusetts Department of Marine Fisheries (MADME) has closed the area for
harvesting except for bait (Ralph Stevens, MADMF, 1993, personal communication).
Limited water quality data are available for the Neponset River at its confluence with
Dorchester Bay; however, water quality in the river is likely influenced by combined sewer
overflows (CSOs) and non-point source pollution (NAI 1990). Historical data have shown high
variability hi fecal coliform concentrations at the mouth of the Neponset River (NAI 199la).
Bacteria and dissolved oxygen are likely the two most limiting factors on water quality in
Dorchester Bay, although a complete assessment of water quality cannot be made at this time.
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Squantum Point (QUI-03)
AQUATIC RESOURCES
There are no freshwater streams or ponds on the Squantum Point site, although several
depressions may intermittently retain surface water.
Marine resources are influenced by conditions in both the Neponset River and
Dorchester Bay. Thus, although the intertidal area is broadly defined as tidal flat with a fringing,
patchy salt marsh, substrate conditions vary dramatically, depending on exposure. The following
description of intertidal communities is based on studies performed by NAI in 1990. Physical
conditions appeared little changed in subsequent site visits by NAI in May 1993.
The intertidal zone was narrowest (65 feet) in the easternmost portion of the site,
broadening to more than 1000 feet at the northwest comer. Salt marsh vegetation was patchy and
best developed along the western side of the parcel. Sediments in the upper intertidal zone were
predominantly sand, grading to pebbles and then silly sand within about 50 feet of the bulkheaded
shoreline. At the northern end of the point, sandy sediments extended 100+ feet from the
shoreline. Seaward, sedimentsweresilty sand/sandy silt with large quantities of shell hash. There
were extensive blue mussel (Mytilus edulis) beds in the lower intertidal zone along much of the
northern border of the site.
Dominant benthic infauna of the northerly exposed tidal flat included the spionid
polychaetes Streblospio benedicti, Polydora cornuta and Pygospio elegans; oligochaetes; soft-shell
clam spat (Mya arenaria); and nematodes (NAI 1990). These species typically exhibit wide
temporal fluctuations in abundance but represent potentially important food resources for higher
trophic levels because of their high abundances. These same taxa were also abundant in the areas
of intertidal sandy beach. The additional prevalence of the longer-lived maldanid polychaete
Clymenella torquata in the beach community suggests that environmental conditions have
exhibited consistent patterns in the recent past, allowing the establishment of a stable benthic com-
munity. A microfloral community appeared to be established along the north-facing tidal flat.
The chlorophyll a concentrations indicated a moderate to high potential for utilizing nutrients
contributed by the Deer Island treatment plant and other sources (NAI 1990).
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Squantum Point (QTJI-03)
The intertidal substrate along the western border of the site was primarily fine-grained
sediments with large quantities of shell hash. Salt marsh broadened from about 5 to 15 feet
moving south along the site. Mussel beds were extensive about 600-700 feet offshore. The
benthic community along the western boundary of Squantum Point exhibited the typical
opportunistic dominants, spionids and oligochaetes, as well as abundant soft-shell clam spat. Less
abundant taxa add to the diversity and food-resource value of the flat (NAI 1990) and contribute
substantially to the biomass available for consumption by foraging fish, megainvertebrate fauna
I.
and shorebirds. The sediment surface yielded high values for chlorophyll a (NAI 1990).
The tidal flats were described as productive clam beds by Chesmore et al. (1971).
There continues to be a large soft-shell clam population in this area, averaging 16.5 clams/ft2 (NAI
1990). Clams were sparsest along the northern boundary and most abundant at the northwest
comer. Mean size was 5.3 cm with 62% of the clams being larger than 5 cm (harvestable size).
Presently, harvesting of shellfish is prohibited except for bait because of contamination (Ralph
Stevens, MADMF, 1993, personal communication). Live razor clams (Ensis directus) were also
observed.
The blue mussel beds were dense aggregations with abundances averaging 58/ft2, and
over 90% alive (NAI 1990). Benthic infauna were very abundant in the vicinity of the mussel
beds. Unlike the other parts of the intertidal zone, the mussel beds supported a variety of arthro-
pods (mostly amphipods) and other mollusks, with soft-shell clams being numerically dominant.
Dominant annelids were the same ubiquitous taxa. Few burrowing species were represented.
Chlorophyll a values were moderate to high.
Finfish and epibenthic fauna were not investigated. The abundance and diversity of
habitat available for benthic infauna indicate the suitability of the Squantum Point intertidal zone
to provide trophic support for these consumers. Species such as green crabs (Carcinus maenas)
and other crabs (Cancer sp.) are likely to forage among the mussel beds and open tidal flats and,
in turn, be preyed upon by wading birds. Flounder and other demersal fish, particularly juvenile
stages, use intertidal areas extensively for feeding. The MADMF officially recognizes the
Neponset River as a spawning run for rainbow smelt. MADMF considered the anadromous
4ft %
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Squantum Point (QUI-03)
fishery resource of the Neponset River to include a large smelt run, a limited shad run and a river
herring (alewife and blueback) run (MADMF 1990, personal communication).
An area of potential concern in the vicinity of the Squantum Point site is a bed of
submerged vegetation in the Neponset River that extends from Commercial Point to an area
beyond Tenean Beach (MWRA 1987). The extent and character of this resource has not been
determined.
The Squantum Point intertidal area was rated as having a high potential for aquatic
diversity and abundance and a moderate-to-high potential for nutrient retention/transformation
(NAI 1990). The extensive shellfish beds around the entire flat and fine sediments on the western
shoreline suggest a high potential for sediment/toxicant retention. This site has a high potential
for shellfish habitat as indicated by the variety of substrate conditions and mollusk species present.
The large food resources in this tidally influenced area indicate a moderate-to-high potential for
providing fish habitat. Similarly, the tidal flat resources are potentially important for migratory
shorebirds. The breadth of the intertidal area offers sediment and shoreline stabilization, although
the open exposure to the north and erosion behind the sheetpile wall indicate that storm tides
reach the upland edge of the site.
VEGETATION
Random seed dispersal and tolerance of the degraded and artificial substrates
remaining after past uses have influenced the type of vegetation that has developed on the site.
Vegetation has not developed to the point of presenting well-defined classes with good structure
and habitat, owing at least in part to the compacted fill substrate which serves as soil. Two broad
upland vegetation classes currently exist within the confines of the seawall: early successional
shrubland, approximately 10-15 feet tall; and old field encroaching on the abandoned runways and
perimeter road.
Most of the site is covered by aggressive plant species, able to withstand disturbed
conditions. The mixture of shrubs, grasses and forbs is dominated by sumac (Rftus typhina),
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Squantum Point (QUI-03)
bayberry (Myrica pensylvanicd), poison ivy (Toxicodendron radicans) and multiflora rose (Rosa
multiflora), making foot travel difficult. Grass species include quackgrass (Agropyron repens),
upland bent (Agrostis perennans) and broom beardgrass (Schizachyrium scoparium), while the
forbs are predominantly Eurasian invaders, including wild carrot (Daucits carota), mugwort
(Artemisia vulgaris), heath aster (Aster ericoides) and tansy (Tanacetum vulgare).
WETLAND RESOURCES
The on-site and adjacent wetland areas described herein were field delineated by NAI
in 1990 using the 1989 federal identification methodology (NAI 1990) and are those areas
estimated to fall within the review of Section 404 of the Federal Clean Water Act. Also
documented are those associated wetland resource areas, identified from published references or
by field observation, that are protected under the jurisdiction of the Massachusetts Wetlands
Protection Act (MGL c 131, s 40) and its implementing regulations (310 CMR 10.00). These
include: 1) Land Under the Ocean, 2) Coastal Beach, 3) Salt Marsh, 4) Land Containing Shell-
fish, 5) Fish Run, 6) Land Subject to Coastal Storm Flowage, and 7) Bordering Vegetated
Wetland. Also present is a regulated buffer zone extending 100 feet inland and/or upland of the
coastal beach, salt marsh, and bordering vegetated wetland.
During the 1990 wetland delineation, on-site construction activities associated with
the Deer Island staging facility continuously changed terrestrial site characteristics. Therefore, the
team of wetland scientists had problems clearly identifying on-site conditions. The 1993 site visit,
however, indicated more stable conditions. Existing fill soils and transitional vegetation greatly
complicate wetland delineation. Should Squantum be chosen for final design a comprehensive
wetland resource evaluation and boundary delineation will be required using the current state and
federally approved methodologies.
Several acres of salt marsh are found on Squantum Point, outside and adjacent to the
seawall. These are interspersed with areas of tidal flat and coastal beach. The largest band of salt
marsh lies on the northwest corner, outside the wall, and runs southward beyond the site. This
salt marsh band consists almost entirely of cordgrass (Spartina alterniflord), with minor amounts
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Squantum Point (QUI-03)
of sea lavender (Limoniwn cf. nashti) and seaside goldenrod (Solidago sempervirens), and has a
substrate of sand and cobbles. The width of the marsh averages approximately 30 feet, with its
upper limit coinciding with the high tide level. A strip of coastal beach approximately 10 feet
wide included the apparent mean high tide line, above which beach grass (Ammophila brevigulata)
dominated to the base of the seawall. Several small patches of salt hay (Spartina patens) were
interspersed with beach grass.
Landward of the seawall, fills and disturbed surfaces dominate the area. The
hydrology is very difficult to discern, owing to the presence of an old subsurface drainage system
of unknown extent. At one culvert break along the northern wall, erosion has initiated a depres-
sion along 15 feet of the wall, now colonized by some beach and salt marsh species: cordgrass
(S. alterniflora), reed (Phragmites australis), sea-blight (Suaeda linearis), seaside goldenrod (S.
sempervirens) and saltwort (Salicornia europaea).
The northwestern shore supports a more patchy, irregular salt marsh which extended
seaward from the base of the seawall. Dominated by cordgrass, this marsh was obviously situated
in a high energy environment as indicated by the eroding peat on its seaward face, and the
deteriorating condition of the seawall behind it.
A 1.0± acre brackish wetland with an ephemeral hydrologic connection with
Dorchester Bay lies about 300 feet inside the seawall, and is surrounded by upland vegetation and
soils. Appearing as an open herbaceous community, the plant species include a mixture of
freshwater and salt-tolerant plants. It is dominated by red-top (Agrostis alba), rushes (Jimcus
effusus and Jimcus gerardi), cattail (Typha angustifolia), three-square sedge (rush) (Scirpus
americanus), purple loosestrife (Lythrwnsalicaria) and seaside goldenrod (S. sempervirens). This
wetland drains to the northwest through a low-lying iron catch basin and culvert placed at such
an elevation and slope that allows the highest spring and storm tides to back flow through the
culvert, bringing salt water into the wetland's northwest corner. The wetland soil is mineral, and
clearly hydric. It has some permeability but little or no organic content, as would be expected with
recently formed soil. Immediately following a two-day, 2 to 4 inch rainfall, the wetland had no
ponded waters, but the fill substrate was fully saturated. Approximately 0.1 cubic feet per second
(CFS) was running out of the culvert. Other small areas of wetland may occur in slight depres-
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Squantum Point (QUI-03)
sions among early-succession shrublands and would require delineation if this site were selected
for final design.
In 1990, the inland wetland was evaluated using the Hollands-Magee freshwater
wetland model (NAI 1990). Results indicated that the wetland had a very low hydrologic and
structural diversity, resulting in low biological value. Scores for nine of ten wetland functional
elements using the Hollands-Magee model rated below median; only aesthetics rated above
median, mostly due to the abundance of showy flowering plants. This means that this wetland
ranks below most New England inland wetlands in the NAI database for all the Hollands-Magee
values other'than aesthetics.
WILDLIFE,
The old-field portion of the site is somewhat diverse, with an intricate mix of shrub
and herb layers providing habitat/edge conditions. The shrub layers form an interconnecting
network, providing habitat for numerous ground animals, including cover and food for small to
medium-sized mammals and resident, migratory and wintering bird species. Observed on-site
mammal species included: muskrat, house cat, mouse (evidence); and several bird species:
common grackle, ring-necked pheasant, northern flicker, American goldfinch, song sparrow,
eastern kingbird, gray catbird, American robin, yellow warbler and short-eared owl. The tangles
of poison ivy and multiflora rose provide cover and food (e.g., berries) for many of these species.
Small trees, such as red cedar and poplar, provide nesting places for birds with substantial height
requirements (e.g., American goldfinch, eastern kingbird), whereas the rose-ivy tangles are
excellent for low nesters (e.g., song sparrow: Harrison 1975). Animal movement into and out
of the area is restricted mainly to urban species, aquatic species, and birds because of the site's
isolation from other wild or open areas.
Little wildlife value can be attributed to the inland wetland community, due to the low
food value of the plants and low value for cover. Outside the seawall, however, the mixture of
salt marsh, beach and tidal flats provides extensive habitat for migrating and resident shorebirds.
These interspersed resources, combined with the high diversity of marine invertebrates, provide
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Squantum Point (QUI-03)
excellent food resources for birds such as turnstones, yellowlegs, sanderlings and smaller sand-
pipers. During field visits, double-crested cormorants were observed utilizing open water, with
herring gulls, great black-backed gulls, ring-billed gulls, brant, greater yellowlegs, black-bellied
plovers and mallard ducks in the beach and tidal flat areas.
THREATENED AND ENDANGERED SPECIES
The Massachusetts Natural Heritage and Endangered Species Program (MANHESP)
records did not identify any protected species or habitats which occur on the site (MANHESP,
letter dated March 1, 1993).
A short-eared owl was observed on-site during fieldwork on November 5,1990. This
owl is presumed to have been migrating from the more populated Canadian tundra breeding
grounds or occupying a wintering ground at the time it was seen. Most short-eared owls in the
east breed much farther north in open country and then winter from northern New England south
to the Chesapeake Bay (Johnsgard 1988). This species may utilize any wet meadow habitat in
the Boston Harbor area during the winter. The Squantum Point area is unlikely to provide
suitable habitat for breeding, due to small size, urban setting and high present levels of
disturbance. This species is listed by Massachusetts as an endangered breeding species. This
species is of worldwide distribution. In New England, it is most commonly seen as a migrant and
winter visitor in coastal fields, airports and salt marshes (Johnsgard 1988). It is known to actually
breed in a very few locations in New England, mostly coastal. It prefers open grassland habitats
where abundant small mammals are available as prey - especially meadow voles (Merotus
pennsylvanicus). Brackish marshes connected to tidal flowage and wet grassland areas often have
an abundance of such small mammals.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
Detailed information regarding historical and archeological resources on Squantum
Point was obtained in 1990, when the site was under consideration for development (NAI 1990).
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Squantum Point (QUI-03)
For that study, documentary research for assessing possible historical and archeological resources
included consultation of the State Register of Historic Places, files and materials at the
Massachusetts Historical Commission (MHC), the Quincy Historical Society and the Boston
Landmarks Commission as well as insurance atlases and maps. Data on known prehistoric sites
were collected from the MHC, interviews with local archaeologists and individuals, and cultural
resource management reports. USDA soil surveys were examined for stratigraphic data. A site
walk was conducted to locate surface cultural remains and to assess the archeological sensitivity
of the site. The 1990 study and a follow-up file review at MHC in 1993 revealed no known
historic resources on the site or its environs.
Approximately 11 prehistoric sites are recorded from the Squantum area. These sites
include shell middens as well as dog and human burial areas, which primarily date to the Late
Woodland, Contact and Early Historic periods. No sites are recorded for the project area.
SOCIO-ECONOMIC/LAND USE
This former naval air station, a 44+ acre site, is now owned by the Metropolitan
District Commission (MDC), which intends to build a waterfront park as funds become available.
Part of the site is used as a ferry docking facility to transport construction personnel to Deer
Island for the Boston Harbor Clean-up Project (reference). This facility includes parking for 930
vehicles. The ferry facility will be made available to the MDC upon completion of the
construction of the sewage treatment plant at Deer Island. The remainder of the site is a mixture
of paved area and shrubs. To the east of the site is the Village at Marina Bay, a mixed-use
development including residences, a marina, offices, restaurants and shops.
Quincy has a long history, beginning as a prosperous farming community and the
home of two Presidents. Major industrial facilities including the former Fore River Shipyard now
line its coast along with residential uses. Much of the land area in Quincy is devoted to park use.
The population of 86,182 is 90% white and 6% Asian. The median family income is $44,184.
Higher-income households have settled in Quincy with the development of new housing in and
adjacent to Marina Bay.
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Squantum Point (QUI-03)
Access to the subject site is via 1-93 south to Neponset Circle, Route 3 A to Quincy
Shore Drive, an MDC parkway and from there, to a connector road to Commander Shea
Boulevard. Existing mudflats around Squantum Point presently constrain marine access, therefore
dredging would be required.
2.1.1.2 Environmental Consequences
In several respects, Squantum Point would provide the most suitable disposal option
of the short-listed land-based sites. With its estimated capacity of 210,000 cy, the site could
potentially accommodate the entire volume that could be reasonably dewatered for land-based
disposal; it is currently in a disturbed state due to the presence of the abandoned runways,
underdrains, and seawalls; and can be accessed by barge, although some dredging would be
required, which would eliminate trucking related difficulties. The major limitations of the site
include the dredging impacts and the site's proximity to the residences of the Village at Marina
Bay.
DIRECT IMPACTS
Permanent Loss
Direct impacts at Squantum Point would include the filling of the shrublands and
abandoned runways of the site. Although disturbed, this area currently provides wild open space
on a heavily developed harbor. No unusual wildlife are known to breed at Squantum Point,
although a short-eared owl (a Massachusetts breeding endangered species) was observed on the
site in November 1990. This individual was probably overwintering or migrating through, feeding
on the mice and voles that are common in such areas. Filling the site would destroy the current
habitat, making it unavailable to any species during the dredging phase of the BHNIP. With
completion of the dredging, the containment facility would be capped and landscaped. If desired,
the plantings could be done to provide some habitat improvement for target species (e.g., open
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Squantum Point (QUI-03)
natural grasslands to attract birds of prey), thereby ultimately enhancing the site's ability to
support wildlife.
Temporary Loss
Dredged material would most likely be delivered to the site via barge, requiring
dredging of a 60-foot-wide channel from the Deer Island ferry channel to the northeast corner of
the site. This dredging would impact approximately 1.4 acres (13,000 cy) of subtidal habitat, and
0.3 acres (6500 cy) of intertidal habitat, some of which may include a narrow band of salt marsh.
Impacts to aquatic resources would include destruction of existing benthic communities in the
dredged channel, although the new channel bottom, which would be an average of 6 feet deeper
than present depths, would likely be re-colonized by benthic organisms similar to those impacted.
Permanent Alteration
Channel dredging hi the 0.3± acre intertidal zone would result in the conversion of
tidal flats and salt marsh to subtidal habitat. It is presumed that the tidal flats and salt marsh
provide protection of wildlife habitat and of marine fisheries including shellfish. Other benefits
include storm damage prevention, groundwater supply protection, flood control and pollution
prevention. Primary functional losses would include a 0.3 acre reduction in migratory bird resting
and feeding areas, intertidal productivity, water quality treatment and shoreline stability. Impacts
to migratory bird habitat would include the permanent loss of the dredge channel area as well as
temporary impacts in the vicinity due to disturbance from project activity. Loss of intertidal
productivity would be greatest in the salt marsh area where primary productivity is highest.
Nutrient transformation is significant in both tidal flat and salt marsh habitats, although the
shallow subtidal dredge channel, when recolonized, would also perform that function to some
extent. Shoreline stability would be affected by both loss of the buffering capacity provided by
existing gentle grades, and the disruption of the erosion-resistant salt marsh peat that currently
forms a continuous band along the northeastern (exposed) side of the site. Engineered protection
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Squantum Point (QUI-03)
against storm-driven waves and long-shore currents or refilling the access channel after disposal
would possibly be required to minimize erosion.
The freshwater wetland currently known to exist on the site would not be impacted,
however, should this site be selected for disposal, the wetlands should be remapped because of
the disturbances and changing hydrology of the site.
INDIRECT IMPACTS
Increased turbidity and redeposition of suspended sediments during the dredging
process could cause temporary impacts to adjacent benthic communities.
Upon closure of the project, freshwater runoff would be directed via swales to outfalls
on the north and west sides of the site. The outfalls would open at the concrete/sheetpile seawall,
and runoff would then cross the bands of salt marsh. During storm events, freshwater flow across
the intertidal zone could impact infauna by creating osmotic stress. This would be most
significant for species whose recruitment period is limited, such as soft-shell clams. Adults can
isolate themselves from short-term perturbations by retracting their siphons. Spat are located at
the sediment surface. Those located in the runoff path could die if freshwater runoff coincided
with low tide. Runoff would reach mussel beds only during major storm events, due to the
location of this resource in the lower intertidal zone. This would likely be of little impact due
to the animal's ability to seal itself off, and to the short duration of exposure in each tidal cycle.
Loss of productivity on the tidal flat would depend on the design of the outfall and
quantity of flow. The overall ability of the tidal flat to support, finfish and shorebirds could be
reduced by the intermittent loss of productivity in the runoff path, both by benthic microfiora and
invertebrates. However, this would likely be a minor impact since only a relatively small portion
of the flat would be affected. Other functions of the intertidal area would be little impacted.
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Squantum Point (QUI-03)
GEOLOGY/SOIL
The placement of 935,880 cy of dredged material (predominantly silts) should not
severely impact the previously altered site geology and soil conditions. These silts would not be
placed in or on any existing resources (e.g., wetlands), and would be placed with appropriate
containment (capping) and sedimentation/erosion controls.
HYDROLOGY/WATER QUALITY
Groundwater impacts are difficult to anticipate due to the complex drainage system
currently underlying the site, but would be expected to be minor because of the likely dominance
of marine hydrology. Surface water from runoff would be directed so as to minimally alter
current hydrologic budgets of surrounding lands and tidal flats. The site's flat topography would
naturally limit impacts from altered runoff patterns.
Because the quality of groundwater resources at this site is unknown, potential impacts
cannot be fully addressed. However, a liner would be required by the MADEP and should
minimize leachate contamination of the groundwater.
AQUATIC RESOURCES
No freshwater ponds or streams occur on the Squantum Point site, so there would be
no impacts on these resources.
WETLAND RESOURCES
The avoidance of any filling or other activity directly affecting protectable resource
areas was established as one of the design criteria for the containment facility. Therefore, impacts
would be limited to dredging a barge access route, and are described in the previous section. A
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Squantum Point (QUI-03)
detailed final investigation would be required to confirm that no other jurisdictional wetland
resources occur in the shrub tangles on the site. No encroachment into the buffer zone associated
with the Bordering Vegetated Wetland or Coastal Beach is proposed.
HISTORICAL AM) ARCHEOLOGICAL RESOURCES
Because there are no listed historical or archeological resources at or near the
proposed Squantum Point site, no impacts are anticipated. However, the site is an artificially
.filled landform, and cultural or prehistoric resources could lie buried below. No adverse impact
would be expected as long as no subsurface activity is conducted. If excavation were required,
then machine-excavation with archeological monitoring would be recommended to determine the
existence of potentially significant remains from either the Naval Air Station or small, isolated,
intact prehistoric sites.
SOCIO-ECONOMIC IMPACTS
The site is proposed for development of a waterfront park by the MDC. Use of
Squantum Point for dredged material disposal could delay and potentially alter these plans.
Potential mitigation for loss of the planned park would be to design a park that would be
compatible with the site after it was capped.
Odor and noise from the dredge disposal could affect residences and businesses in the
Village at Marina Bay. Odor could be minimized by chemically treating or covering the disposal
site daily with clean material. Noise impacts could be reduced by restricting usage during
nighttime and other sensitive periods.
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2.1.2 Everett nEVR-04)
The Everett site is approximately 23 acres in size in a "U" shaped parcel around a
shallow inlet on the Mystic River (Figure Al-3). The Boston/Everett Corporate boundary bisects
the parcel so that approximately two-thirds of the site lie in Everett and one-third in Boston.
Boston Edison Company owns the Everett parcel. The Boston parcel is city-owned and currently
has a 3VDDC pumping station located on the southern side. This site discussion will focus on the
15-acre Everett parcel.
2.1.2.1 Existing Conditions
GEOLOGY/SOILS
Soils on the site consist primarily of Udorthents with a wet substratum. Udorihents
are defined as fill soils over former tidal marshes, and other wetland resources (SCS 1989a,
1989b). The depth of fill ranges from 2 to 20 feet or more, with seasonal high groundwater
ranging from 3 to 5 feet below the surface.
Based upon the mapping of Kaye (1980), the central portion of the site is underlain
by bedrock consisting of sandstone or quartzite while the northern and southern portion of the site
l
is underlain by sandstone argillite, with minor interbedded sandstone and/or quartzite. Bedrock
has been mapped as outcropping near the site and the average depth to bedrock on site may be
relatively shallow.
HYDROLOGY/WATER QUALITY
There are no surface waters on the site, so the hydrology is fairly simple. The
topography of the site is flat, therefore most precipitation will infiltrate to the groundwater or be
taken up through evapotranspiration. Any water that does run off most likely will run into the
Mystic River.
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Everett (EVR-04)
The site consists of low-yield aquifers (<100 gpm) with half the site being classified
as low and the other half as very low (MADEP Groundwater Overlay Maps). There are no wells
on site or within 0.1+ mile. Groundwater quality is influenced by tidal action and is probably
saline in nature. Also, there are several hazardous waste sites near the site which may have an
influence on groundwater quality. The site is not suitable as a drinking water supply. No data
were available for groundwater quality at the site.
The Mystic River is classified as Class SC by MADEP. Waters under this
classification are saline and designated for the protection and propagation of marine life and for
secondary contact recreation. Water quality in the vicinity of the site is most likely influenced
by several NPDES discharges into the Mystic River.
Water quality data for the Mystic River are available from sampling done by MADEP
in 1982-1986 (Menzie-Cura and Associates 1991). Samples were taken downstream and near the
confluence of Island End River. Results of this sampling indicate that the average concentrations
for cadmium, copper, and lead exceeded the chronic criteria for aquatic life. The acute aquatic
life criteria for cadmium, chromium, copper, lead, and zinc were exceeded on at least one
occasion.
AQUATIC RESOURCES
The aquatic resources near the Everett site were not sampled; however, substrates
appeared to be made up of fine-textured sediments in the exposed intertidal areas. It is likely that
the subtidal communities are similar to those observed in the Mystic River and pier areas of
Mystic Piers, Revere Sugar, and Amstar (as detailed in later sections). The intertidal areas may
support soft-shell clams (M. arenarid), but are likely to have small populations due to the fine-
textured substrates.
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Everett (EVR-04)
VEGETATION
The upland portion of the site is flat and dominated by early-successional grasses,
forbs and scattered saplings. Plant cover is sparse on approximately 50% of the site, where gravel
and old asphalt dominate. These areas have poor quality rooting substrates and also appear to be
periodically used by vehicles entering the site. The remainder of the site has better herbaceous
coven dominant species include several clovers (Trifolium spp.), grasses including broom
beardgrass (Schizachyrium scoparium), mugwort (Artemisia vulgaris), goldenrods (Solidago spp.),
milkweeds (Asclepias spp.) and bird's foot trefoil (Lotus corniculatus). Scattered saplings of
cherries (Primus sp.), trembling aspen (Populus tremuloides), gray birch (Betula populifolid), and
staghom sumac (JR. typhind) occurred across the site, and are most prevalent on the western leg
of the parcel. This leg in general appeared to be less disturbed, with better herbaceous and
sapling cover.
Common reed (P. australis) occurred in patches around the periphery of the inlet at
the top of the bulkheads. Because the bulkheads appear to be well above the high tide line, and
would not impound freshwater, these stands of common reed appear to be opportunistic, occurring
in upland settings. One exception may be the seaward edge of a small stand in the northwest
corner of the inlet. In this area the fill behind the bulkhead has collapsed and may be exposed
to tidal inundation during exceptionally high tides.
WETLANDS RESOURCES
No delineation of jurisdictional resources was performed at Everett; however, areas
of tidal waters will fall within the purview of Section 404 of the Federal Clean Water Act.
Massachusetts jurisdictional resources ((MGL c.131, s.40, and 310 CMR 10.00)) on the site
include coastal bank, tidal flats, coastal beach and land under the ocean. A 100-foot buffer area,
inland of the top of the coastal bank occurs on the east and west portions of the site. Small areas
of coastal beach and coastal bank occur along the seaward end of the east and west portions of
the site. These resources are composed of eroding fill, and have been partially reinforced by
boulders and rubble.
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Everett (EVR-04)
With the possible exception of the seaward edge of the common reed stand as
described in the previous section, no vegetated freshwater wetlands occur on site. During the site
visit, a pool of standing freshwater was observed in an asphalt depression in the northeast corner
of the site. The lack of requisite soils and vegetation preclude this as a wetland.
WILDLIFE
The paucity of vegetation and the surrounding urbanization limit the value of the
Everett site for terrestrial wildlife. Animals typical of urban settings, such as rock doves,
European starlings, house sparrows, and house mice might use the site, as would birds that nest
on bare ground, such as killdeer. The western leg of the site, which is somewhat more densely
vegetated, also would support species typical of herbaceous or "old field" habitats: for example,
common yellowthroat, song sparrow, and meadow vole (DeGraaf and Rudis 1986). A song
sparrow was heard in this area during 1993 site visits.
The intertidal flats and river bordering the site would be of more value to wildlife than
would the site itself. Herring gulls and great black-backed gulls were observed feeding on the
intertidal flat between the inlet and Route 99 on May 12,1993. On May 25,1993, a black-bellied
plover, a semipalmated plover, and a killdeer were observed foraging on the intertidal flat along
the Mystic River on the southwest comer of the project area. Common terns, a Massachusetts
Species of Special Concern (321 CMR 10.60) were observed courting and apparently nesting on
the dilapidated pier on the western side of the inlet. While only pilings remained for most of the
length of the pier, the outermost section remained intact and formed an isolated platform on which
the birds were seen. A great black-backed gull, a potential nest predator, also seemed to be sitting
on a nest on the same platform on May 12, but a gull observed on May 25 exhibited no nesting
behavior.
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Everett (EVR-04)
THREATENED AND ENDANGERED SPECIES
MANHESP records indicate that no protected species or habitats occur on the site
(MANHESP, letter dated March 1, 1993).
Common terns feeding and courting were observed near the Everett site during two
site visits in May 1993. As stated above, the common tern is a Species of Special Concern in
Massachusetts. Four terns were sitting on the dilapidated pier in the inlet on May 12. One was
seen to stand and pull material on the ground closer to itself. This activity and the posture of the
birds suggested that they were sitting on nests on the old pier. During a subsequent field visit on
May 25, six common tems were observed to exhibit nesting behavior. Terns were also observed
foraging in the Mystic River near the site.
HISTORICAL AM) ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources on the Everett site. A
I
jackknife bridge was inventoried by MHC within 1000 feet upstream of the site. It has been for
sale since 1990 and may have been dismantled (Mr. W. Smith, MHC, pers. comm.).
SOCIO-ECONOMIC/LAND USE
This site is a narrow basin abutting 28+ acres of vacant land on the north side of the
Mystic River in Everett. It is surrounded by industrial uses including a Boston Edison power
station. A rail line abuts the western boundary of the site. There is a park and playground
facility across Broadway and to the north of the site.
Everett was originally a territory of Charlestown, its neighbor across the Mystic River.
A fanning community for 150 years, Everett evolved into an industrial city with the advent of the
railroads that facilitated transportation to Boston. Factories for brick manufacturing and the
production of chemicals, located hi Everett in the 19th century, have been joined by facilities for
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Everett (EVR-04)
metal product fabrication and machinery in the past 100 years. The predominant land use in
Everett is residential. Everett's population of 35,701 is predominantly white with a median family
income of $37,397.
Land access to the site is from 1-93 to Sullivan Square hi Charlestown, and traveling
north on Route 99 (Broadway) across the Mystic River. The parcel surrounding the basin abuts
Route 99 to the east. Mud flats extend along the Mystic River edges, making access for vessels
difficult. Some dredging would be required to accommodate barges related to the material
disposal project.
2.1.2.2 Environmental Consequences
Everett is the smallest of the land-based potential disposal sites with an estimated
capacity of 55,000 cy.
DIRECT IMPACTS
Permanent Losses
The site is a vacant lot in an urban setting, and as such offers habitat for typical urban
species such as song sparrows, rock doves, and house mice. Most of this habitat would be
impacted with the construction of the containment facility, and the resident animals displaced or
destroyed. Upon capping and closure of the project, its value as open space in an urban setting
would be restored, and most of the species currently using the site should return.
The placement of dredge spoils and the proposed containment facility would eliminate
all existing vegetation within the disposal footprint. Upon completion of all on-site activities,
natural recruitment and early stage succession of tolerant and opportunistic species should occur.
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Everett (EVR-04)
Temporary Loss
The preferred route to the site would be via barge which would require dredging to
deepen the inlet channel to reach the existing granite bulkhead. This would result in the loss of
approximately 0.3 acres (2300 cy) of subtidal habitat. The dredging process would destroy any
benthic communities in the dredging corridor, although it is likely that similar benthos would re-
establish in the deepened channel. Existing depths average 5.0 feet MLW, therefore dredging an
additional 5.0 feet would be necessary to achieve a final 10.0 foot channel depth. Turbidity and
redeposition of suspended sediments could cause temporary impacts to adjacent benthic
communities during the dredging process, although these communities would be expected to
recover quickly following completion of the dredging.
A second possible approach for barge traffic would provide access from the western
leg of the site. However, this would require dredging of 0.2+ acres (5000 cy) of intertidal and
0.03 acres (200 cy) of subtidal habitats. This approach would also impact an area of coastal
beach, coastal bank and buffer. Because of the variety and extent of impacts to protected
resources, this approach is considered a less desirable alternative than the inlet channel.
Activities during construction of the facility and dredged material disposal could
discourage use of the adjacent tidal flats by shorebirds; however, this is a limited resource in terms
of area and location, so the interruption would not be expected to be an adverse impact. Use of
the site by these birds should resume after capping and closure.
Noise and disturbance during construction and operation of the containment facility
could disrupt use of the dilapidated pier by nesting common terns (Massachusetts Species of
Concern). The extent of use and success of these small, isolated, urban breeding sites is poorly
understood, therefore impacts from adjacent construction activities are difficult to assess. It is
likely that the birds would abandon the breeding site during project operation, and could return
upon project closure.
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Everett (EVR-04)
GEOLOGY/SOILS
As with Squantum Point, the on-site udorthents represent an unnatural/altered site
condition. Therefore, the placement of dredge spoils would not severely alter or change existing
geological and/or soil conditions.
HYDROLOGY/WATER QUALITY
Because of the Everett site's proximity to tidal waters, impacts to hydrologic
conditions from dredge material disposal, capping and closure would be minimal. Infiltration
would be eliminated by the liner system required by MADEP, minimizing impacts to groundwater
flow. Surface runoff would be directed to minimize alterations to the existing hydrologic budgets
of surrounding lands and tidal flats.
INDIRECT IMPACTS
A playground is located a block away from the site, and a school is less than a half-
mile away. Odor from the site and from trucks travelling to the site would be the greatest impact
to these sensitive receptors. Daily cover or treatment of the dredged material may be required.
Truck traffic already is heavy along Route 99, so the increase in safety hazard and noise caused
by transportation of the dredged material may need to be evaluated, although increases over
existing levels may not be noticeable. It is unknown to what extent any increase in truck traffic
would result in additional traffic delays. If barges are used to transport material to the site, traffic
impacts would be eliminated. Noise from industries and traffic already occurs in the area.
Therefore, it is not expected that the increase in project noise would be a problem.
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Everett (EVR-04)
AQUATIC RESOURCES
No freshwater runoff impacts at site closure would be anticipated because runoff could
be discharged directly into subtidal waters, therefore eliminating impacts to intertidal communities.
WETLAND RESOURCES
I
Under the preferred barge access route, no wetland resources other than Land Under
Ocean would be impacted (see previous section). The containment facility footprint would not
impact any protected resources.
HISTORICAL AM) ARCHEOLOGICAL RESOURCES
Because there are no identified historical or archeological resources at the Everett site,
no impacts would be anticipated. The jackknife bridge upriver of the project would not be
impacted.
23 SITE EVALUATIONS; LAND-BASED INLAND SITES
2.2.1 Wobnrn fWOB-11)
The Woburn site is a 59-acre parcel in the Town of Wobum adjacent to the
Wilmington town line (Figure Al-4). The site is primarily owned by the town, but is bisected
by a parcel owned by Boston Edison Co. High power transmission lines travel the Boston Edison
parcel and are joined approximately halfway up the site by a transmission line from the northeast
along an easement corridor. These power lines effectively trisect the site into 3 parcels: a
southern parcel approximately 18 acres in size, an eastern parcel of 13 acres,and a northern parcel
estimated to be 24 acres. This assessment will concentrate on the northern parcel for use by the
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Woburn (WOB-11)
BHNIP. It is dominated by a temporarily capped municipal landfill, with steep slopes
approximately 10-25 feet in height.
2.2.1.1
Existing Conditions
GEOLOGY/SOILS
The topography of the Woburn site is irregular with rounded uplands separated by
relatively flat lowlands. The topography of the site reflects the surficial and bedrock geology of
the area. The surficial deposits at the site consist of stratified drift and glacial till. The low lying
areas of the site are underlain by stratified drift which includes kame and kame terrace deposits
of sand and gravel (Castle 1959). Portions of the lowlands have been mined to extract the sand
and gravel for use as aggregate material. The upland portions of the site are underlain by dense,
poorly sorted glacial deposits of silt, sand and gravel.
Outcrops of bedrock have also been observed (Castle 1959). The bedrock underlying
the site has been mapped as Precambrian age metamorphosed mafic to felsic intrusive and
volcaniclastic rocks (Zen 1983). These rocks are part of a large fault-bound block which trends
northeast to southwest.
The majority of the soils on site are classified as landfill or udorthents (SCS 1989b).
Two udorthents are distinguished: on the southern parcel is a sandy udorthent with 3-8% slopes;
and on the eastern parcel is a udorthent with a wet substratum. The depth of fill over wetland
material is unknown, and within the udorthent series can range from 2-20 feet (SCS 1989b).
Small areas of native soil occur on the northern boundary (Charlton-Hollis-Rock complex, 3-8%
slopes) and adjacent to the stream in the southern parcel (Windsor loamy sands, 3-8% slopes).
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Woburn (WOB-11)
HYPROLOGYAVATER QUALITY
The site is located in the Mystic River Basin immediately south of its drainage divide
with the Ipswich River Basin. Runoff at the site appears to flow to a small stream in the middle
of the property, which flows west to east across the site and then south into Hall's Brook (also
known as Willow Brook). Locally, groundwater is recharged by the infiltration of precipitation
into the surficial deposits. Groundwater appears to flow through the stratified drift deposits to the
southeast and then discharge to the valley fill deposits of the Aberjona River.
Most of the site consists of low and very low yield aquifer with 20% of the site
consisting of medium yield aquifer (100-300 gpm) (MADEP Groundwater Overlay Maps). There
are no groundwater quality data available for the site. It is not known if water quality has been
degraded by the existing landfill on the site. The Wobum residential areas near the site rely on
Quabbin water through the MWRA, so no private drinking water wells are known to occur
downgradient of the site.
At its northern boundary, the site is approximately 1200 feet away from the nearest
boundary of the Wilmington Groundwater Protection District A. This district is designated to
protect the "zones of contribution of the existing municipal supply wells" (Town of Wilmington
1990). The nearest Wilmington water supply well, the Town Park well, is over 0.8 miles to the
north and upgradient of the Woburn site. Three other Wilmington municipal wells are within
approximately 1.0 mile of the site.
The site is located in the upper portion of the Mystic River drainage basin. The only
surface water on the site is a tributary of Halls Brook which is classified as a Class B waterway.
Waters under Class B are freshwaters designated for the uses of protection and propagation of
aquatic life and wildlife and for primary and secondary contact recreation. There are no surface
water supplies downstream of the site. No water quality data exist for this brook, but as with
groundwater, the on-site landfill may have the potential to influence water quality.
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Woburn (WOB-11)
AQUATIC RESOURCES
No aquatic resources occur within the proposed footprint of the Woburn site. A stream
tributary to Hall's Brook flows through the southwestern portion of the site. At the time of the
site visit, the stream flowed very slowly in an easterly direction and was approximately 6-10 feet
wide and 1 foot deep. A red brown floe coated many of the stream's bottom features, including
the vegetation. No culvert was visible where the access road crossed the stream, although a slight
current was apparent. It is assumed that the hydraulic crossing is that of a "farm drain" which
allows flow through rock placed at the base of the road and permits flow through their interstices.
VEGETATION
The major portion of the site is a disturbed early-successional field and shrubland.
Several small stands of hardwoods remain on the northern portion of the site, and along the small
stream. Scattered shrubs, representative of disturbed-site species and most of Eurasian origin,
have become established throughout the site.
On the northern parcel, dominant species on the closed landfill include mugwort
(Artemisia vulgaris), alfalfa (Medicago lupulind), grasses (Two Poa spp. and Bromus tectorwri),
clovers (Trifolium repens and T. pratense), and goldenrods (Solidago spp.). Scattered small
individuals of black locust (Robinia pseudoacacid), honeysuckle (Lonicera tataricd), and tree of
heaven (Ailanikus altissimd) have become established across the cap. On the steep slopes of the
landfill, stands of trees approximately 30-40 feet in height occurred on the east and north sides.
Common species included trembling aspen (P. tremuloides), gray birch (B. populifolid), and
staghom sumac (JR. typhind).
The disturbed old field portion's of the southwestern and eastern parcels support
species similar to the plant community on the landfill cap in the northern parcel.
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Woburn (WOB-11)
WETLAND RESOURCES
Several areas of freshwater wetlands which will fall within the purview of Section 404
i
of the Federal Clean Water Act were observed on the Woburn site. Wetland resources as
protected by the Massachusetts Wetlands Protection Act and Regulations (MGL c.131, s.40, and
310 CMR 10.00) include Bordering Vegetated Wetlands, Isolated Land Subject to Flooding, Land
Under Water Bodies and Waterways, and Banks. The following describes the various wetland
_
resources from general observation. No jurisdictional wetland boundary delineations were
performed since site access was limited.
Adjacent vegetation was primarily woody. On the eastern side of the access road,
shrubs overhung most of the stream's length; species included common and European buckthorn
(Rhamnus caihartica and R. franguld), red maple (Acer rubmm), willow (Salix sp.) and
honeysuckle (L. tataricd). On the western side of the access road, small trees (20-30 feet in
height) of red maple, mulberry (Moms alba), black willow (Salix nigrd), and gray birch
dominated the stream corridor.
Small isolated wetlands occur in depressions elsewhere on the site. Under the
powerline, several herbaceous wetlands less than 0.1 acre in size were observed; along with
considerable trash, common plant species included cattail (T. angustifolia), bluejoint grass
(Calamagrostiscanad'ensis), soft rush (J. effusus), and jewelweed (Impatiens capensis). Northwest
of the on-site landfill, a small apparently isolated forested wetland occurred at the base of the
landfill slope. Standing water in the middle open portion of the wetland was estimated to be 2.0±
feet deep at the time of the site visit, and stagnant in appearance (heavy pollen accumulation, dark
brown in color). Last year's herbaceous stems were visible well into the flooded zone, which
suggests that water levels will drop significantly as the growing season progresses.
The canopy was quite open, and dominated by red maple, black willow and big-tooth
aspen (Populus grandidentata), with willow and European buckthorn in the shrub layer. The herb
layer contained limited species; a composite thicket condition formed a dense homogenous
herbaceous cover in the flooded portion of the wetland. Along the edges, jewelweed and water
horehound (Lycopus sp.) occurred, along with common reed (P. australis) and Japanese knotweed
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Woburn (WOB-11)
(Potygomon cuspidatum) which crept down the slope of the landfill and encroached on the
wetland.
A review of aerial photography revealed a small pond further to the north, occurring
very close to the Woburn town line, and a more extensive forested wetland system in Wilmington
in close proximity to the northern edge of the site. Neither area was visited during field work,
but would not be impacted by the project design.
WILDLIFE
Mammal species typical of sites such as the closed landfill, with sparse herbaceous
vegetation, include woodchucks and eastern cottontails. The scattered shrubs and adjacent forest
also provided perches or nest sites for species such as indigo buntings, song sparrows and
common grackles, all of which use open land or forest edge. Eastern kingbird, tree swallow, and
hoary bat are examples of wildlife species that forage over open land and also use adjacent trees
for perching, nesting or roosting (DeGraaf and Rudis 1986). The many rocks and other debris
on the landfill top also provided good cover for species such as brown snakes and common garter
snakes (Hunter et al. 1992).
The hardwood forest on the side slopes of the landfill area was young, with an open
canopy (about 40-50% cover), and well-developed shrub and herbaceous layers. Species observed
in the forest/shrub habitat included gray catbird, common yellowthroat, song sparrow, and yellow
warbler. All of these species typically are associated with brushy habitats.
Several forested wetlands occurred in the area north of the landfill. Wildlife species
most likely to occur in these wetlands would include those also able to use the adjacent landfill
(e.g., common yellowthroat, song sparrow), adjacent developed sites (e.g., skunk), or the adjacent
fragmented forest (e.g., coyote, raccoon). Some species typical of forested wetlands would be
unlikely to use the smaller site (e.g., northern waterthrush and veery: DeGraaf and Rudis 1986,
Robbins et al. 1989). .
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following:
Wildlife species observed on the site on either May 12 or 27, 1993, include the
Common garter snake (Thamnophis sirtalis)
Red-tailed hawk (Buteo jamaicensis)
American kestrel (Falco sparverius)
Ring-necked pheasant (Phasianus colchicus)
Killdeer (Charadrius vociferus)
Northern flicker (Colaptes auratus)
Blue jay (Cyanocitta cristatd)
American crow (Corvus brackyrkynchos')
American robin (Turdus migratorius)
Gray catbird (Dwnetella carolmensis)
Northern mockingbird (Mimus polyglottos)
European starling (Sturnus vulgaris)
Yellow warbler (Dendroica petechid)
Common yellowthroat (Geothlypis trichas)
Rose-breasted grosbeak (Pheuctictts ludoviciamis)
Indigo bunting (Passerina cyaned)
Field sparrow (Spizetta pusilld)
Song sparrow (Melospiza melodid)
Red-winged blackbird (Agelaivs phoeniceus)
Common grackle (Quiscalus quisculd)
House finch (Carpodacus mexicanus)
American goldfinch (Carduelis tristis)
Rabbit (Leporidae family)
Woodchuck (Marmota monax)
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Woburn (WOB-11)
THREATENED AND ENDANGERED SPECIES
The Mystic Valley Amphipod (Crangonyx aberrans) is a crustacean that occurs in
cool, shallow, slow-moving or stagnant fresh water with leaf litter; and is only known to occur
in New England (MANHESP 1991). It is a Species of Special Concern in Massachusetts. C.
aberrans has been recorded south of the site in Hall's Brook (Lincoln 1993; MANHESP, letter
dated March 1, 1993). The on-site tributary has several of the habitat characteristics required by
the Mystic Valley Amphipod: shallow depth, sluggish velocity and leaf litter.
No search for C. aberrans was undertaken on the study area, but a 1991 survey
sampled the tributary to Hall's Brook downstream of the study area (NAI 1991b). One immature
Crangonyx, which could not be identified to species, and 17 Crangonyx pseudogracilis were
collected at this sample point, but no adult C. aberrans were recorded at any sample point during
the 1991 study. Since C. pseudogracilis typically occupy the same habitat as C. aberrans (Smith
1983 cited by NAI 1991), this survey reported no C. aberrans even in suitable habitat.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources identified on or within 1000
feet of the Woburn site.
SOCIO-ECONOMIC/LAND USE
Woburn (11) is an 59+ acre site containing a city landfill and vacant land. Boston
Edison power transmission lines cross the site, dividing it into three pieces. People use the site
for dirt-biking. The Boston and Maine Railroad tracks run in a north/south direction east of the
site. Adjacent to this site is an office park to the east; another office park to the south, along with
an industrial park and some residential use; general industrial and residential to the west; and
general industrial to the north with some limited residential use.
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Woburn (WOB-11)
Woburn, originally known as Charlestown Village, was settled in 1636 by people
seeking relief from crowded conditions in Charlestown. Once a farming community, Woburn
housed leather tanning and shoe manufacturing operations in the 19th century after the Middlesex
Canal was built. These industries have been superseded by metal fabrication and the manufacture
of electrical equipment. The predominant land use remains low-density housing. The population
of Woburn declined 2% to 35,943 from 1980 to 1990 . The median family income in Wobum
is $50,428.
2.2.1.2
Environmental Consequences
The Woburn site can potentially accommodate 158,600 cy of silt. A major
engineering drawback of this site is the dome shape of the former landfill that currently dominates
the site. The dome would require extensive regrading to construct the basin configuration of the
dredge containment facility. The stability and condition of the landfilled material is currently
unknown, and would require analysis to ascertain its status for construction. However, a long-
term benefit gained by the use of this site would be the secure capping and closure of the landfill,
which currently is loosely capped with a coarse mineral cover. Capping would eliminate the
present infiltration and leaching from the portion of waste that is above the watertable. Any waste
in contact with the groundwater would continue to leach.
DIRECT IMPACTS
Permanent Losses
The placement of dredge spoils and the proposed containment facility would eliminate
all existing vegetation within the construction footprint. Upon completion of all on-site activities,
early-stage succession of tolerant and opportunistic species should occur. A vegetation plan may
be required for the landfill cap, since shallow-rooted species are generally preferable in
maintaining cap integrity.
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Woburn (WOB-11)
The preliminary design incorporates avoidance and minimization of all wetland
resource impacts in its design criteria. As a result, most of the wetlands on the Woburn site and
their buffer zones would not be impacted. The exception is a small 1.0± acre forested wetland
on the northwest side of the site, hi which fill would be placed to ensure adequate sideslope
stability during closure of the existing landfill. More detailed site information would be necessary
to further quantify surface area impacts to the wetland from any fill. The functions and values
of this wetland have not yet been evaluated but due to its small size, isolation, and disturbed
conditions, the wetland is expected to be of relatively low value for biological support, flood
control, wetland wildlife habitat and water quality functions. Aesthetic, recreational, and
educational values are also expected to be low because of its disturbed setting and lack of public
access. Therefore, impacts to this area of wetland would likely be minor.
Construction of the containment facility would result in the loss of all upland wildlife
habitat within the disposal footprint until capping and closure of the site were completed. Upon
closure of the project, there would be an opportunity for natural recruitment and restoration and
improved habitat quality by eliminating exposed trash and future dumping. As described above,
a limited permanent wetland wildlife habitat loss would also occur, but is expected to be of
minimal significance.
Temporary Losses
Travel to the site would be along secondary and local roads and would pass by
residences. Truck traffic to the site could increase noise and odor levels and could create safety
problems, particularly along Merrimac Street and New Boston Road. A new exit from Route 1-93
and development of a proposed rail siding east of the site will not be completed in tune for
BHNIP's schedule.
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Woburn (WOB-11)
GEOLOGY/SOILS
On-site udorthents represent an unnatural and altered soil condition. Given the sandy
gravelly deposits, placement of silry dredge spoils could change the surficial character of on-site
soils not associated with the landfill. The dredge spoils could provide quality material for capping
of the landfill area.
HYDROLOGY/WATER QUALITY
Because the quality of groundwater resources at the Woburn site is unknown, potential
impacts cannot be fully addressed. However, a liner would be required by MADEP and would
minimize leakage of contaminants from the dredged material into the groundwater. A potential
benefit of using this site is that an unsecured landfill would be capped by the dredging project.
This action could result in improvement of the groundwater quality by eliminating the present
infiltration and leaching of that portion of the waste deposited above the water table. Any waste
in contact with groundwater would continue to leach.
To avoid impacts from high chloride levels, the dredged material would be dewatered
at Boston Harbor prior to transport to the Woburn site. Dewatering facilities are described in the
dredge management plan (Section 3.0 of the EIR/S); monitoring requirements of MADEP would
be in place to keep impacts from the dewatering process to an acceptable level in the surface
waters of Boston Harbor.
No impacts to surface waters surrounding the disposal site are anticipated during the
dredge disposal phase. The leachate collection system and the liner would be used to collect any
excess water or contaminants. Leachate treatment would be controlled to prevent impacts to the
!
surrounding environment. At the end of the dredge disposal phase (2± years), the site would be
capped with an impermeable cover to prevent further infiltration or surface water runoff from the
dredged material.
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Wobnrn (WOB-11)
After the site has been capped and revegetated, runoff quality should resemble that
of adjacent undeveloped land. Runoff quality should also improve because the currently sparse
vegetation, steep slopes, exposed soils and trash are all likely to degrade existing runoff quality.
AQUATIC RESOURCES
Runoff into wetlands adjacent to the site would be controlled to keep sediments from
entering the wetland during the dredge disposal phase. After site closure, runoff would be
redirected to best approximate the pre-project water budget of these wetlands.
THREATENED AND ENDANGERED SPECIES
No known threatened and endangered species use the Woburn site; therefore, no
impacts would be anticipated.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources on or near the Woburn site;
therefore, no impacts would be anticipated.
SOCIO-ECONOMIC/LAND USE
The site is an abandoned landfill, intersected by powerlines and a sewage pipe. The
site is primarily owned by the City of Woburn, with a parcel owned by the Boston Edison Co.
Use of this site for the project would not result in any loss of tax revenue to the City of Woburn,
since no work would be done near the powerline. The powerlines and pipeline on the site would
not be impacted by the project. Also, capping the site after project completion would save the
City of Woburn the expense of capping the existing landfill.
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Woburn (WOB-11)
The site is primarily industrial, with some nearby residences. Noise and odors from
the site could affect some of these residences. Odors would possibly need to be controlled daily
by covering the dredged material. Daily cover requirements would reduce the available site
capacity. Noise and odor also would be lessened by prevailing winds. The direction of prevailing
winds is from the west, and no residences occur immediately east of the site.
2.2.2 Wrentham (WREN-495)
The Wrentham site is approximately 181 acres in size, and is located at the
intersection of US Route 495 and Route 1A (Figure Al-5). The site is undeveloped and is
bordered primarily by 1-495, open land and an active sand and gravel pit (Bardon Trimount
Quarry and Asphalt Plant). Several single family residences lie within 500 feet on the east and
west of the site; an abandoned railroad bed forms the eastern boundary. Privately owned by
Simeone Corporation, the site is bisected by a power transmission line for which New England
Power Company has an approximately 325 ft wide easement. The northern portion of the site
currently has a proposal for a 23-acre sand and gravel operation in anticipation of an industrial
subdivision (Landmark Engineering of New England, Inc., 1993). Because this site is private
property, on-site access was not gained; observation are from the site borders, aerial photographs
(black and white, 1:6000, dated December 11,1991), and resource maps (1987 U.S.G.S. Franklin,
MA topographic quadrangle and the 1989 SCS soil survey).
2.2.2.1 Existing Conditions
GEOLOGY/SOILS
The topography of the Wrentham site ranges from an upland area in the northeast
portion of the property to several water filled depressions in the central and southern portions of
the property. The upland areas are underlain by dense, poorly sorted glacial till and bedrock. The
lowland areas in the central and southern portions of the property are underlain by stratified drift.
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Wrentham (WREN-495)
Portions of the stratified drift deposits in the southern portion of the property have been mined
for sand and gravel.
Outcrops of bedrock are found in the upland portions of the property. Based upon
the Bedrock Geological Map of Massachusetts (Zen 1983), the bedrock underlying the site consists
of the Precambrian Age Dedham Granite. Dedham Granite is part of a structural block which
trends northeast to southwest. In the vicinity of the property the Dedham Granite is traversed by
a north to south trending normal fault
Soils on the site are predominantly well drained and somewhat excessively drained
outwash and till soils (SCS 1989a). Except for the level idorthents in the quarry areas, slopes
range from 3-8% to 15-35%. The Charlton-Hollis-Rock Outcrop complex includes a dominant
sandy till, but also included are till areas of Canton fine sandy loam, and outwash deposits of
Hinckley fine sandy loam and Merrimac fine sandy loam. A linear unit of ponded Freetown
muck, a very deep organic deposit, is associated with a small stream on the western edge.
HYDROLOGY/WATER QUALITY
The site is underlain by medium yield aquifer; approximately one-third of the site is
designated as MADEP Zone H Wellhead Protection Area (MADEP Grqundwater Overlay Maps).
There are no municipal drinking water wells located on the site as the area is primarily serviced
by a municipal piped system. No groundwater quality data were available for the site. There is
a proposed municipal well approximately 0.15 miles west of the site. This proposed well location
is in the Blackstone River basin, out of the watersheds of the project study site; however, actual
groundwater divides may not coincide with surface watershed boundaries.
The north and west portions of the site are located in the Charles River basin while
the south portion is in the Ten Mile River basin. There are several small ponds and a stream
located on the site, but no water quality data were available. Surface waters on the site in both
watersheds are classified as Class B waterbodies. Waters under Class B are fresh and designated
for the uses of primary and secondary contact recreation and for the protection and propagation
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Wrentham (WREN-495)
of aquatic life and wildlife. Several private wells are near the site for residences on portions of
Green Street and Route 1A.
AQUATIC RESOURCES
Several small kettlehole ponds occur within the central project area. Most appeared
to be steep sided; however, the largest pond (on the eastern side of the site) was shallow, with
aquatic vegetation visible throughout. On the western edge of the site lies an unnamed stream
which drains to Eagle Brook after flowing north through a series of off-site ponds. In June, the
stream was approximately 4.0 feet wide and 6 to 8 inches deep, with a sand and detritus bottom
and sluggish flow.
VEGETATION
Vegetation cover types and wetland identification were ascertained from stereo aerial
photographs (black and white, 1:6000, dated December 1991), and ground truthed only
peripherally from the old railroad grade, Green Street, and an improved gravel road bisecting the
site. Should this site be selected, a more thorough site investigation would be required to
determine jurisdictional wetland boundaries and more detailed vegetation descriptions.
The scrubland northwest of the active quarry area was on a low rolling dry plain
bordered by several prominent rock outcrops. Based on vegetation composition and structure, the
soil appeared to be well-drained poor sands with an average litter layer. The vegetation was
dominated by a mixture of oaks, approximately 15 feet tall and many with multiple stems. Oak
species included red oaks (probably Quercus coccinea and Q. ntbrd), scrub oak (Q. illicifolid) and
white oak (Q. alba). Minor representatives of other tree species such as red maple (Acer rubrwri),
cherries (Primus spp.) and gray birch (B. populifolid) were also observed. Tall snags of white
pine (Pimts strobus) were scattered across the site. The understory was dominated by a lowbush
blueberry (Vaccinium sp.), with sweet fern (Comptoniaperegrind), meadowsweet (Spirea latifolia)
and blackberry (Rubits sp.) also common. The herbaceous layer was sparse and indicative of dry
site conditions: bracken (Pteridium aquilinum), Pennsylvania sedge (Carex pensylvanicd) and
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Wrentham (WREN-495)
haircap moss (Polytrichum sp.) were dominant species. Even a small swale running the length-
of the site appeared to be dominated by upland species, again supporting the SCS classification
of well-drained soils on the site.
Shrublands elsewhere on the site were similar in structure and general species
composition. Other common species included multiflora rose (Rosa multiflord), willows (Salix
spp.), poison ivy (T. radicans), and tree-of-heaven (A. altissima). The forested portions of the
site were hardwood-dominated with red oaks and white ash (Fraxinus americcmd) as the principal
species. Other observed species include sassafras (Sassafras albidum), sugar maple (Acer
saccharum), big-tooth aspen (P. grandidentatd) and white pine. Understory species included
white oak, gray birch, black cherry (P. serotina), poison ivy, and lowbush blueberry as well as
canopy species. Structure was typical of second-growth forests of the area; canopy height was
approximately 70 feet, with a maximum stem diameter at breast-height of about 18 inches, and
an estimated 70% canopy closure.
Several small open areas of old field occurred. Soils were obviously poor and well
drained, with many surface rocks and cobble. The vegetation was typically early-successional,
dominated by forbs such as asters, goldenrods, yarrow (Achillea sp.), ragweed (Ambrosia artemis-
iifolia), wild carrot (Daucus sp.), grasses (Poa compressaand others), and sedges (Corex brevior).
Scattered shrubs (willows, meadowsweet and sweet fern) were established.
WETLAND RESOURCES
Several areas of freshwater wetland occur across the Wrentham site will be subject
to review under Section 404 of the Federal Clean Water Act. Jurisdictional resources under
Massachusetts Wetlands Protection Act and Regulations (MGL c.131, s.40, and 310 CMR 10.00)
on the Wrentham site include Bordering Vegetated Wetlands, Land Under Water Bodies and
Waterways, Isolated Land Subject to Flooding, and possibly Banks.
In the northern and western portions, forested wetlands occurred either in isolated
depressions on the landscape or.associated with small ponds. On the far western edge lies an
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Wrentham (WREN-495)
unnamed stream system which drains into Eagle Brook. The stream is bordered by a wide swath
of wooded wetlands, except where it traverses a residential landscaped lot. The wooded wetland
is primarily red maple (A. rubrwri) with a minor element of white ash and other species. The
understory was relatively dense with woody species such as red maple, swamp azalea (R
viscosvm) and spice bush (L. benzoin). Herbaceous species included sensitive fern (Onoclea sensi-
bilis), royal fem (Osmunda regalis), skunk cabbage (Symplocarpus foetidus) and sedges (Carex
sp.). Immediately bordering the stream, the overstory opened up to a dense shrub swamp.
On the southern and eastern portions of the site, where the vegetation is predominantly
low secondary growth, scattered shrub wetlands in isolated basins and in small drainages occur.
Under the powerlines, vegetation is maintained by mowing or herbicides, and emergent/shrub
wetlands were evident on the aerial photographs. Several small kettlehole ponds dot the central
portion of the site. These ponds generally appear to be steep sided with few bordering wetlands.
The largest pond was observed from the railroad tracks to have a narrow band of shrub swamp
bordering its shores. The pond was shallow throughout, with pond lilies and emergent species
dominating most open water areas. A narrow shrub swamp separated this pond from an adjacent
smaller pond, but a surface hydrologic connection almost surely occurs at high water levels.
WILDLIFE
The scrublands could be expected to support many of the species typical of dry,
brushy habitat (e.g., American redstart, gray catbird, New England cottontail: DeGraaf and Rudis
1986; redbelly snake: Hunter et al. 1992). The rufous-sided towhee, is typical of brushy habitat,
I
forages in leaf litter (DeGraaf and Rudis 1986), which was abundant at this site.
The hardwood forest had a good vertical structure, with well-developed shrub and
herbaceous layers. Wood thrush and woodland jumping mouse are typical of this forest type
(DeGraaf and Rudis 1986). A well-developed layer of duff, a stonewall, and abundant logs would
favor small animals requiring cover: for example, chipmunks, masked shrews, and redback
salamanders (DeGraaf and Rudis 1986).
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Wrentham (WREN-495)
A small early successional field in the southern comer of the site contained sparse
herbaceous vegetation, with some scattered shrubs and an occasional tree. Common yellowthroat,
song sparrow and mourning dove would be expected in this habitat type. This habitat may be
suitable for the northern hairstreak, a butterfly which is described in the "Threatened and
Endangered Species" section.
The ponds appear to have poor interspersion of vegetation types and vegetation and
water. Therefore, it is likely not to be important for waterfowl brood rearing. Canada goose scat
was observed on the pond edge. These geese probably were feeding there.
The stream, moist soil and dense shrub layer in the red maple swamp would attract
species such as veery, short-tailed shrew and yellow warbler (DeGraaf and Rudis 1986) as well
as two-lined salamanders (Hunter et al. 1992), all of which would not occur in the other, drier
cover types.
Some wildlife species may use a combination of habitats. For example, American
kestrels may perch in the snags jutting above the scrubland and forage above the scrubland and
in the adjacent early successional field (DeGraaf and Rudis 1986). White-tailed deer from the
forest may browse on saplings and shrubs in the scrubland. Eastern kingbirds or eastern phoebes
may hawk insects above the shrubs from perches at the forest edge or hi the supercanopy snags.
The Wrentham site and its vicinity are intersected by a powerline, an interstate
highway, several secondary roads, a dirt road, and a gravel mining operation. It is too fragmented
to be used by species that breed in large tracts of unbroken forest (e.g., black-throated blue
warbler: Robbins et al. 1989). However, wildlife species that use a variety of habitats and that
have home ranges of a half-mile or more in diameter may use the site as part of their domain.
Examples include red fox, striped skunk and raccoon (DeGraaf and Rudis 1986).
The following species of wildlife were observed on the project site on May 12 and
June 21, 1993:
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Wrentham (WREN-495)
Bullfrog (Sana catesbeiand)
Canada goose (Branta canadensis)
Red-tailed hawk (Buteo jamaicensis)
Killdeer (Charadrius vocifems)
Rock dove (Columba livid)
Mourning dove (Zenaida macrourd)
Eastern phoebe (Sayornis phoebe)
Eastern kingbird (Tyranmis tyranmis)
Blue jay (Cyanocitta cristatd)
Tufted titmouse (Partis bicolor)
American robin (Turdus migratorius)
Gray catbird (Dumetella carolinensis)
Northern mockingbird (Mmus polyglottos)
European starling (Sturnus vulgaris)
Blue-winged warbler (Vermivora pinus)
Prairie warbler (Dendroica discolor)
Indigo bunting (Passerina cyaned)
Rufous-sided towhee (Pipilo erythrophthalmus)
Song sparrow (Melospiza melodid)
Common grackle (Quiscalus quisculd)
House finch (Carpodacus mexicanus)
THREATENED AND ENDANGERED SPECIES
Two species identified by the State of Massachusetts as of Special Concern occur
adjacent to the site (MANHESP, letter dated March 1,1993): and include the northern hairstreak
butterfly (Fixsenia Ontario), and Philadelphia panic grass (Panicum philadelphicum). Both species
are typical of open ground.
The northern hairstreak occurs at disturbed sites that are dry, open and sparsely
vegetated, such as power lines, railroad rights-of-way, and abandoned gravel pits (Hildreth,
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Wrentham (WREN-495)
undated). The old fields and parts of the powerline right-of-way and abandoned railroad bed may
provide appropriate habitat for this species. These areas would need more intensive investigation
to determine whether they provide suitable conditions.
The Philadelphia panic-grass occurs in open areas or thin woods (Fernald 1950). In
Massachusetts, it has been found in open wetlands, along the shores of water bodies, and in
depressions (MANHESP 1992). The most likely place for it to occur on the study area would be
in the wetlands within the powerline corridor and along the banks of open water throughout the
study area.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources on or within 1000 feet of the
Wrentham site.
SOCIO-ECONOMIC/LAND USE
This 181-acre site is predominantly open land, with an active quarry and asphalt plant
at its southern tip. It is located immediately southwest of the Route 1A Interchange on Route I-
495 and near the Wrentham State Forest. The vast majority of the site is undeveloped shrub and
forestland containing some ponds and wetlands. There are some residences abutting the property.
Wrentham was first settled in 1669 and was considered part of Dedham. Industries
that developed in the town during the 19th century included the production of straw hats and
jewelry. The major employer in the town today is the State, reflecting the presence of a state
school for the retarded. The population of Wrentham is 98% white. The median family income
is $51,184.
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Wrentham (WREN-495)
Access to the site is via 1-93 south to Route 1-95 south, and northwest on Route 1-495
to Route 1A to High Street to Green Street and onto the site.
2.2.2.2
Environmental Consequences
The Wrentham site is the largest of the land-based potential disposal sites, with an
estimated capacity of 785,000 cy. This size may be sufficient to accommodate all of the silts
since the dewatering process is likely to reduce the volume of the silts to below the in-situ
volume, however the extent of wetlands and MDEP Zone H Wellhead Protection. Area greatly
reduce the suitability of this site. Due to the permitting and design concerns these two resource
areas raise, this site may be more suitable for consideration as a disposal area for future
maintenance material.
DIRECT IMPACTS
Permanent Losses
The preliminary design of three containment structures within the site incorporates
avoidance and minimization of impacts to wetland resources in its design criteria. As a result,
most of the larger wetlands and wetland complexes would be avoided altogether (based on the
restricted in-field wetland assessment and findings to date and wetlands as mapped on
Massachusetts Bureau of Waste Site Cleanup Resource Maps). Several areas of wooded and shrub
wetlands in the ulterior portions of the two parcels would be filled. Under the preliminary design
presented in the DEIR/S, over. 15.0 acres of identified wetland resources protected under the
Federal Clean Water Act would be impacted. Under Massachusetts regulations, this acreage
includes both Bordering Vegetated Wetlands and Isolated Land Subject to Flooding. Additional
field surveys would be necessary to determine more accurately the extent and proportion of
wetland in each resource category and to assess their functions and values. Reconfiguring the
containment facility to avoid these wetlands would reduce the capacity of the site by approximate-
ly 45% to 430,000 cy.
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Wrentham (WREN-495)
Construction of the containment facilities would result in the loss of all wildlife habitat
within the project footprint until capping and closure of the site was completed, and revegetation
commenced. If managed as open space with natural vegetation, the site would likely regain much
of its current value as wildlife habitat.
The on-site potential for use by the Philadelphia panic grass and Northern hairstreak
should be verified, because both species have been recorded at nearby locations. The scrub-shrub
wetlands and old-field areas are the most likely habitats in which to find these two species,
respectively. These habitats occur throughout the southern portion of the site. Upon detailed field
investigation by experts of these two species, impacts to areas identified as potential habitat would
be avoided.
The placement of dredge spoils and construction of the proposed containment facility
would eliminate all existing vegetation within the footprint. Being a disturbed site, the existing
vegetative composition and structure is of a shrabland, scrubland, and forb dominated old field.
Following capping and closure of the site, this type of vegetative character would likely return.
Temporary Losses
Green Road already is used heavily by quarry trucks. The project would increase
truck traffic. Odors from dredged material along the truck route could be a concern.
INDIRECT IMPACTS
Much of the northern portion of the site is within a MDEP Zone II Wellhead
Protection Area (Bureau of Waste Site Cleanup Resource Maps), which violates DEP's landfill
siting suitability criteria (310 CMR 16.40:3(a)l). Although the proposed containment facility
would be lined and have a leachate collection system, the potential risk of contamination of the
aquifer through liner leakage or failure cannot be eliminated. Reconfiguring the containment
facility to avoid the Zone II aquifer would reduce Wrentham's capacity to 710,000 cy.
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Wrentham (WREN-495)
Avoidance of both wetland and Zone n aquifer resources results in the elimination
of the northern cell entirely, and an overall reduction in the capacity of the site by approximately
60% to 315,000 cy.
Construction of the facility would result in the fragmentation of a relatively large tract
of undeveloped land which could discourage use by those wildlife species which require large
areas. This impact would be expected to be moderate because the forest and shrub communities
are common in the region, and the study area presently contains an active gravel and asphalt
operation. Upon closure and revegetation of the site, the fragmentation effects would be
minimized as the vegetation succeeds and matures.
The site would require regrading prior to construction of the lined containment facility
and deposition of the dredged silts. These activities could require extensive earthmoving of
sandy/gravelly till and filling with silt, thus potentially changing general surface soil characteris-
tics. Blasting or drilling could be required to remove all or a portion of the existing bedrock
outcrops.
The site is presently worked, and represents an altered. condition; therefore, the
placement of the containment facility and dredge spoils would not adversely impact existing
geologic and/or soil conditions.
HYDROLOGY/WATER QUALITY
As with the Woburn site, impacts to surface water would be minimized during the
dredge disposal phase by a combination of dewatering the dredged material prior to transport to
the site, and by maintenance of a liner and leachate collection system.
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Wrentham (WREN-495)
These actions would prevent chloride, sediment and any sediment-related contaminants
from entering surface waters. Dewatering facilities are described in Section 4.0 of the FEIR/S;
MADEP discharge and monitoring requirements would keep dewatering impacts to surface water
quality within an acceptable range in Boston Harbor.
Runoff from capped portions of the disposal site would be controlled so as to
minimize erosion risks prior to entering any surface water system.
AQUATIC RESOURCES
As described in the Water Quality section, the on-site stream and small ponds would
be protected from contamination during the dredged material disposal phase by dewatering prior
to on-site disposal, and by the liner-leachate collection system. Surface runoff from the project
would be treated using appropriate erosion control methods and controlled to avoid directly
entering aquatic habitats. After site closure, runoff from the project area would be redirected to
best approximate the pre-project water budgets of surrounding aquatic habitats.
HISTORICAL. AND ARCHEOLOGICAL RESOURCES
Since there are no listed historical or archeological resources on or near the Wrentham
site, no impacts are anticipated.
SOCIO-ECONOMIC ISSUES
Odor and noise from the site should not be a concern near the quarry and asphalt plant
because they would not likely be distinguishable from existing noise and odor levels there.
However, in the northern part of the project, which is farther away from the plant and closer to
the residences, odor and noise could become a concern. Daily cover or chemical treatment of
dredged material could be required to control odors.
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Wrentham (WREN-495)
The project site is owned by Simeone Corporation, which has proposed to extract sand
and gravel from the portion of the site that abuts Route 1-495 in preparation for an industrial
subdivision (Landmark Engineering of New England, Inc. 1993). Use of the northern part of the
site by the project would deprive the Town of Wrentham of existing tax revenue as well as the
potential tax revenue from the subdivision. Use of the southwestern parcel would result in loss
of existing tax revenues, as well as any potential for future development
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Landfills
2.2.3
Landfill Sites - An Overview
Three private solid waste landfills within reasonable haul distance have been identified
that could accept portions of the dredged silt material. These three sites include Laidlaw Waste
Systems Sanitary Landfill at Plainville, BFI-Northern Disposal, Inc. hi East Bridgewater and
Fitchburg/Westminister Sanitary Landfill in Fitchburg. All are lined facilities with leachate
collection systems. None have special waste permits but all are willing, within their MADEP
Solid Waste Site Assignment restrictions, to accept dredged material pending MADEP and local
board of health approval. Table Al-1 summarizes the features and constraints of each site for
comparative purposes.
Use of a portion of the dredged material as daily and intermediate cover is also a
possibility at all three sites. To be considered suitable for intermediate cover the material must
meet the physical and chemical standards described under 310 CMR 19.00 and expanded on by
MADEP. Use as final cover should also be considered, provided the material meets the 310 CMR
19.00 standards, including criteria for Toxic Characteristic Leaching Procedures (TCLP), pH,
solids, and reactivity.
As required by 310 CMR 19.00, the introduction of a special waste to any of the
candidate sites should not impact the public health, safety and the environment by comprehensive-
ly regulating the storage transfer process, treatment, disposal, use and reuse of solid waste.
Protection of these issues generally requires a comprehensive site evaluation and/or assessment
which evaluates on-site and offsite conditions and receptors relative to public health and
environmental risk. Since these candidate landfill sites are lined and presumed suitable to receive
"special wastes," all issues of public health and environmental risk have been addressed
previously. Therefore, both existing and proposed condition narratives, as contained herein, are
brief. Potential impacts for each candidate landfill site are summarized in Table 2.3.2-7 of the
EIR/S.
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Landfills
2.2.3.1 Existing Conditions
PLAINVILLE SANITARY LANDFILL
Laidlaw Waste Systems' Landfill of Plainville is a double-lined RCRA facility,
operated by Laidlaw Waste Systems, Inc. in Plainville, MA (Figure Al-6). Access is via Route
1-495 to Route 1N and Madison Street, with an approximate travel time of 1.0 hour from Boston
Harbor (35± miles).
Although no dredged material has been landfilled at the Plainville site, they have
accepted grit and screenings from MWRA sewage treatment projects. Plainville was considered
for the disposal of dredged material from the Moran terminal on Boston Harbor but a different
site was selected. The landfill can accept materials containing up to 1000 ppm total petroleum
hydrocarbons. Materials must contain at least 40% solids. Laidlaw engineers must review bulk
sediment test results, and materials for disposal must contain no free-standing water. Any further
need for testing will be determined by the MADEP. Coordination with the Plainville Board of
Health consists of submitting an information package about the proposed disposal to the Board
for review.
The landfill is very concerned about odor control, because of a campground near the
site. Deodorizing agents will be required after disposal should odor problems develop.
Plainville expects to exceed its permitted capacity in 1995, but has several expansion
proposals in various stages of preparation. One of the proposals, currently undergoing MADEP
review, would extend the site's capacity for approximately one year, if approved. Three other
expansions could potentially provide disposal capacity until the year 2000.
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Landfills
rCHBTJRGAVESTMINSTER SANITARY LANDFILL
Fitchburg/Westminster is a lined solid waste facility operated by Resource Control,
Inc. in Fitchburg, MA (Figure Al-7). Access is gained via Princeton Road off Route 2, with an
approximate travel time of VA hours from Boston Harbor (45± miles).
The landfill has not received dredged material for disposal but has accepted
petroleum-contaminated soil and wastewater treatment plant sludge. In addition to meeting 310
CMR 19.00 standards, waste disposal material must be at least 25% solids and contain no free-
standing water upon arrival at the site. No nuisance materials can be accepted at the landfill, so
disposal material must be odor-free. Local coordination with both the Westminister and Fitchburg
Boards of Health is required.
Fitchburg/Westminster expects to exceed its permitted capacity in 1997. No
expansions are currently proposed.
EFT-NORTHERN DISPOSAL. INC.
Northern Disposal, Inc. is a lined facility operated by Browning Ferris Industries in
East Bridgewater (Figure Al-8). Access'requires taking Route 24 to Route 27 onto Thatcher
Street. Tune of travel is estimated to be 45 minutes from Boston Harbor (25± miles).
This landfill has accepted dredged material from another project in the last three years,
as well as small volumes of sewage sludge and petroleum contaminated soils. This landfill was
selected for the disposal of dredged material from the Moran Terminal on Boston Harbor. The
landfill can accept materials with no free-standing water and a minimum of 20% solids. Approval
for disposal is required from both DEP and the Town of East Bridgewater Board of Health. Odor
is a particularly sensitive problem as several residences are located very close to the landfill.
Deodorizing agents will be required after disposal in the event that odor problems develop.
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Landfills
Northern Disposal, Inc. expects to exceed its current permitted storage capacity in
1996, although it may pursue a vertical expansion.
2.2.3.2 Environmental Consequences
The three landfills under consideration for disposal of the silt sediments are all
constructed to handle the material so as to avoid impacts on the environment. They are all lined
facilities and strictly regulated for waste-stream handling and disposal. Because of their
similarities, they will be addressed together in terms of project impacts using landfills as disposal
options.
Geological and soil conditions at landfills are generally accepted to be severely altered
from pre-landfill dumping activities. Landfills designated for waste or special waste disposal can
readily accept several forms of waste which meet their specific designation. Therefore, specific
impacts on geology/soil would not be an issue.
HYPROLOGYAVATER QUALITY
The dredged material would be dewatered at Boston Harbor prior to being trucked to
a landfill site. Dewatering is required to eliminate standing water and to achieve the criteria for
percentage of solids specified by each landfill. Dewatering at Boston Harbor would reduce the
volume of dredged material and therefore the project truck traffic, and would minimize the
problem of chloride handling in a freshwater environment. The dewatering facility described
under the Dredge Management Plan (Section 4.0 of the EIR/S) would also be utilized for the
landfill disposal option. As with the upland inland sites, no adverse water quality impacts to
Boston Harbor are anticipated due to the MADEP permit requirements.
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Landfills
AQUATIC RESOURCES
No impacts to aquatic resources would occur at the landfill sites or Boston Harbor as
a result of dewatering.
WETLAND RESOURCES
No impacts to wetland resources would occur at the landfill sites or Boston Harbor
as a result of dewatering.
WILDLIFE
No impacts to wildlife would occur at the landfill sites or Boston Harbor as a result
of dewatering.
THREATENED AND ENDANGERED SPECIES
No threatened or endangered species are known to occur at any of the landfill sites,
or at the Boston Harbor dewatering facility, so no impacts would occur.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
No historical or archeological resources are known to occur at any of the landfill sites,
or at the Boston Harbor dewatering facility, so no impacts would occur.
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Landfills
SOCTQ-ECONOmC/LAND USE
Each are existing and active landfills so that their individual or collective use should
j
not pose any additional socio-economic/land use impacts on their respective communities.
2.3
SITE EVALUATIONS: NEARSHORE AQUATIC SITES
23.1 Existing Conditions
23.1.1 Mvstic Piers fMassport Piers 49 & 50)
The site is depicted on Figure A1-9.
SEDIMENT CHARACTERISTICS
Like all of Boston Inner Harbor, the Mystic Piers site is a depositional environment
(EG&G 1984), accumulating fine grained sediments (silts and clays). Sediment sampling along
the harbor-face of Massport's Mystic Piers 1 (Station 1), 49 and 50 (Stations 1 and 2), adjacent
to the proposed disposal site, revealed that the silt-clay component was 41-78%, averaging 60%
(see EER/S Section 2.2). Benthic grabs collected within the proposed disposal area contained
I
predominantly silty sediments, although gravel was present in one sample.
No within-berth data were available for assessing sediment quality. However, all
stations sampled to characterize berth-area dredged materials were within approximately 400 feet
from the mouth of the proposed Mystic Pier disposal site and may be indicative of sediment
quality. Assuming these data reflect conditions within the Mystic Pier site, the sediments are
likely to contain moderate to high levels of metals and organics. Arsenic, chromium, copper and
mercury likely occur in Category II levels; lead and zinc likely occur in Category El levels. Total
PAHs concentrations are likely to be high (>10 ppm), with fluoranthene and benzo(g,h,i)perylene
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Mystic Piers
contributing the highest concentrations. Total organic carbon is likely to be 2-3% of dry weight,
indicating a relatively high potential for bioaccummulation of contaminants.
WATER QUALITY AND CIRCULATION
The area of Boston Harbor adjacent to the Mystic Pier site has been classified as Class
SB waters by the MADEP. This designates these saline waters for the propagation of marine life,
primary and secondary contact recreation and shellfish harvesting with depuration. Water quality
of Boston Inner Harbor is strongly influenced by the numerous discharges into the harbor, includ-
ing CSOs, NPDES discharges and non-point source urban runoff. There is no site-specific water
quality data for the Mystic Pier Site; however, water quality can be characterized by Boston Inner
Harbor data which are described in Section 4.1.1 of the EIR/S. At the Mystic Pier site there is
an outfall pipe, which is a minor discharge consisting of either stormwater, sanitary waste water
or from a minor industrial discharge such as non-contact cooling of equipment (Menzie-Cura and
Assoc. 1991).
The opening of the Mystic Piers site indicates that water exchange between Boston
Harbor and the site is not restricted. Thus, water movement at the Mystic Pier site can be
characterized by Boston Inner Harbor currents (described in Section 4.1 of the EIR/S) which are
tidally diverse.
In general, water quality and circulation are driven by tidal cycles, and influenced by
seasonal weather patterns. High summer temperatures have been reported to depress dissolved
oxygen concentrations, often resulting hi defaunation in the benthos in Boston Harbor (Hubbard
and Bellmer 1989). This condition is commonly referred to as the "August Effect," and will be
also referred to throughout this document.
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Mystic Piers
AQUATIC RESOURCES
The site was visited during low tide on April 28, 1993, to evaluate habitat conditions.
The intertidal zone is restricted to the tidal excursion vertically along the walls and pilings
surrounding the Mystic Piers site, except in the southwest comer where rubble has accumulated
in sufficient quantity to be exposed at low tide. Intertidal portions of the western and northern
walls were covered extensively with algae (primarily Fucus sp. with some Spongomorpha sp.).
The pilings along the southern perimeter were heavily covered with barnacles, blue mussels
(Mytilus edutts) and green algae (Spongomorpha sp.) with algal cover increasing with distance
from the mouth. Diatoms were present on the algae and rubble. Mussels and macroalgae both
provide habitat for other organisms. These communities may be exploited for food or shelter by
crustaceans and finfish.
Benthic Infauna
Two areas were sampled (in April 1993) for benthic infauna. Results (extrapolated
to number/m2) are reported on Table Al-2. Station MP-1, adjacent to the pilings, was nearly
azoic (two taxa totalling 86 individuals/m2) while Station MP-2, near the head of the site,
contained 17,759 individuals/m2 (11 taxa) of which 11,954/m2 were nematodes. The total
abundance at MP-2 was in the range observed by the Corps in the Chelsea Creek and Confluence
Area in 1986. However, the channel stations were dominated by polychaetes (>70%) while the
Mystic Pier station was dominated by nematodes (67%). Capitetta capitata and oligochaetes
comprised 85% of the remaining organisms. These predominant taxa are classified as pioneer
taxa, Nematodes are early settlers in organically enriched sediments whose presence stimulates
microbial degradation of organics (Tietjen 1982). Oligochaetes and C. capitata are typically
associated with organically enriched, stressed environments. Its reproductive strategy enables C.
capitata to colonize disturbed sediments rapidly. No amphipods or live mollusks were collected.
The moderate abundance of infauna (17,759/m2) in at least a portion of the site contributes to the
productivity of Boston Harbor and these near-surface dwelling organisms are available as prey
items for crabs and demersally feeding fish. Winter flounder (Pleitronectes americanus) have
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Mystic Piers
been documented as feeding on C. capitata in Boston Harbor (Haedrich and Haedrich 1974; NAI
1985), although their preferred prey includes amphipods and large worms.
Sediment profile camera sampling in October 1994 at three locations showed two
types of benthic habitat (NAI and Diaz 1995). On the northern side of the site, sediments were
muddy with pit and mound topography, indicative of a depositional environment. The Redox
Potential Discontinuity (RPD) layer, an indication of the degree to which subsurface sediments
are oxygenated, was located at 0.5-1.0 cm below the sediment surface, indicating poor
oxygenation. There were a few infauna tubes at the sediment surface b"ut no other indications of
bioturbation. The information suggests the area is under environmental stress and characterized
by a colonizing or pioneering benthic community. Benthic samples confirmed this assessment.
Only one taxon, the surface-dwelling gastropod Nassariustrivittatus, was collected with a density
of 37.5/m2 (Habitat II, Table Al-3). Abundances were also low in this area in 1993 (MP-1, Table
Al-2).
Sediment profile camera sampling on the southern border of the site revealed fine sand
sediments overlaying silt, suggesting occasional erosional conditions. The RPD layer was located
at 1.3 cm below the sediment surface, indicating greater sediment oxygenation than in the northern
Mystic Pier area. Some indicators of bioturbation, including infauna tubes and anoxic voids, were
observed. Benthic samples from this area revealed a slightly more diverse community (5
taxa/.08m2, Habitat IV, Table Al-3). Total abundance was low (62.5/m2), much lower than that
in the same area (MP-2) in 1993 (17,329, Table Al-2). Dominants included the opportunistic
polychaete Streblospio benedicti, the gastropod Nassarius trivittatus, and amphipod Ampelisca
abdita, which together composed 60% of the total abundance. Numbers of taxa and total
abundance were among the lowest of Inner Harbor stations. The benthic community in this area
would still be considered pioneer or colonizing, but under slightly less environmental stress than
in the northern area at Mystic Piers site.
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Mystic Piers
Finfish were not sampled at this site. However, recent finfish surveys in the Mystic
River and Inner Confluence give an indication of the species that could move into this area.
Haedrich and Haedrich (1974) observed 23 species in the Mystic River including winter flounder,
rainbow smelt, and alewife. A fall 1994 trawl survey of demersal fish in the Mystic River and
Inner Confluence collected .winter flounder, Atlantic tomcod, windowpane, scup and rainbow smelt
(Table Al-4). Scientific names for fish species are provided in Table Al-5. Gill netting in the
Little Mystic Channel at the same time collected rainbow smelt and Atlantic tomcod (Table Al -6).
Characteristics of the Mystic Piers site may enhance the suitability of the habitat for
finfish.' The pilings and wharf, shading the area below, offer shelter from predators. The
orientation of the site perpendicular to the main channel provides shelter from currents. Both
subtidal and intertidal benthic resources in some areas could provide prey items. Soft substrate
could support feeding by demersal species (e.g., winter flounder). Fish such as cunner, tomcod,
and sculpins could feed on the fouling community on the walls and pilings (Edwards et al. 1982;
Menge 1982; Ojeda and Dearborn 1990). Two species of particular concern are alewife and
winter flounder. The anadromous alewife spawns above the head of tide of the Mystic River so
reproductive adults migrate upriver past the Mystic Piers site between April and May (Whitlatch
1982). Adults descend the river during the summer, juveniles swim downriver past the site from
late summer-fall (Loesch 1987). Another anadromous species, rainbow smelt, may also use this
portion of the Harbor. Winter flounder is one of the most abundant species in Boston Harbor
where it is considered to be a resident. It prefers to spawn on sand common in the outer harbor
(Bigelow and Schroeder 1953).
WETLAND RESOURCES
Under the jurisdiction of the Massachusetts Wetlands Protection Act (MGL c. 1 3 1 , s.40
and 310 CMR 10.00) the Mystic Piers site is a Designated Port Area (DP A). DPAs are almost
completely developed areas where few or no natural land forms or vegetation remain. They tend
to be paved, bulkheaded, and used for heavy industry so that they have virtually no significance
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Mystic Piers
to the interests of the Act, except for Land Under the Ocean. Land Under the Ocean in DPAs are
significant to flood control, storm damage prevention, and the protection of marine fisheries, as
is Land Under the Ocean outside of DPAs. The major addition is that Land Under the Ocean in
Designated Port Areas also provides support for coastal engineering structures, such as bulkheads,
seawalls, revetments, and solid fill piers. The site is primarily Land Under the Ocean, potentially
important to marine fisheries, storm damage prevention and flood control. Land Under the Ocean
within the Mystic Pier provides food resources and shelter; however, the silty substrate is not
preferred spawning habitat for winter flounder, nor are the saline conditions conducive to
spawning of the anadromous alewife. Storm damage protection and flood control are provided
by the vertical granite wall surrounding the perimeter of the site.
Under federal wetlands guidelines, the entire Mystic Piers site is defined as Tidal
Waters. The fine-grained character of sediments at the site, as well as proximity to identified
contaminants, suggest that the potential for retention of sediments, toxicants and nutrients exists.
Abundance and diversity of the benthic fauna varied substantially in the site. Compared to other
locations in the harbor, Mystic Piers exhibited moderate potential for supporting higher trophic
levels. Construction activities could be more sensitive at this site due to its proximity to an ana-
dromous fish run (in the Mystic River).
WILDLIFE
The aquatic area of Mystic Piers may be used by waterfowl that dive for food (e.g.,
bufflehead and common goldeneye), birds that hunt fish in the water (e.g., red-breasted merganser
and double-crested cormorant), or those that hunt fish from the air (e.g., common tern and belted
king fisher). Coastal areas are particularly important to waterfowl during the winter. Inland
feeding areas usually freeze, so water-dependent birds such as American black ducks move to
unfrozen waters on the coast.
Abandoned piers provide roosting sites for gulls and common terns. Norway rats are
also commonly associated with waterfronts (DeGraaf and Rudis 1986). Harbor seals may
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Mystic Piers
I
occasionally occur since they generally feed in shallow water inshore (FAO Adv. Comm. 1976,
cited by Chapman and Feldhamer 1982).
THREATENED AND ENDANGERED SPECIES
No federally or state-listed threatened or endangered species are identified or
anticipated to occur within the boundaries of the Mystic Piers site (Lincoln 1993). Although
common terns have been observed nesting within Boston Harbor, no evidence of nesting was
present at the Mystic Piers site on April 28, 1993.
mSTORTCALANP ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources at the Mystic Piers site.
I
SOCIO-ECONOMIC/LAND USE
The inlet between the Mystic Pier No. 1 and Pier 49 is no longer used for cargo
handling at Massport's Moran Terminal in Charlestown. Charlestown. is a neighborhood within
the City of Boston. Recreational vessels docking here in the late 1970s were removed to
accommodate shipping activity. The recreational docking has not been reinstated even though the
port-related shipping activity ceased to operate in the inlet. There are no residential areas abutting
this property. The closest residential neighbors are across the Little Mystic Channel in the Charles
Newtowne complex and in the former Navy Yard.
l
Charlestown, with a population of 14,731, is a dense residential community
surrounded by industrial land use on the north and south edges. To the southeast, the former
Boston Naval Shipyard has been redeveloped into a mixed use complex including residences,
institutions, shops, offices and recreational facilities. The population of Charlestown is 95%
white. From 1980 to 1990 the population shifted with a reduction in the percentage of children
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Mystic Piers
and an increase in the 25-44 year age group. This reflects the new condominiums and apartments
constructed in the Navy Yard and along Main Street. The median family income is $41,638.
2.3.1.2
Revere Sugar
The site is depicted on Figure Al-10.
SEDIMENT CHARACTERISTICS
Benthic samples from the interior portions of the site revealed the sediments to be
anoxic silts with an oily sheen. At the mouth of the site there was a thin oxygenated layer
overlaying anoxic black silts. No samples were collected within the site boundaries for sediment
characterization, but Stations 1 and 2 sampled along the Mystic River berth at Revere Sugar
(Appendix C of the EIR/S) represent probable sediment conditions. Contaminant loads in these
sediments were generally high: Category n levels of chromium and copper, Category III levels
of arsenic, lead, zinc and PCBs; high levels of total PAHs (18-44 ppm) and total petroleum
hydrocarbons. Individual PAHs exhibiting particularly high values (>5 ppm) were pyrene,
phenanthrene, fluoranthene and chrysene. TOC values (3-3.6%) indicate that the potential for
bioaccumulation is high.
WATER QUALITY AND CIRCULATION
Tidal flow and land-based discharges to the Mystic River influence the water quality
of the Revere Sugar site, which is classified as Class SB waters. Dissolved oxygen experiences
August Effect fluctuations at this site.
Circulation within the Revere Sugar site is governed by tidal flow and physical
structures. The northeast corner of the site is likely to experience reduced flows or eddies during
flood tide since the eastern boundary of the site is perpendicular to the primary flow. Similarly,
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Revere Sugar
the northwest corner would experience reduced flows or eddies during ebb tides. The pilings
across the mouth of the site interrupt linear flow and can reduce current speed, enhancing the
likelihood of sediment deposition. The even more numerous pilings along the western and south-
ern edges of the site create the same effect in these areas.
AQUATIC RESOURCES
Habitat conditions were examined at the Revere Sugar site on April 28, 1993. The
intertidal zone is restricted primarily to vertical excursion on pilings and walls. The wooden
retaining wall along the eastern boundary and the abandoned pier on the southern side supported
small quantities of macroalgae (predominantly Fucus sp. with some green algae). Barnacles and
littorinid snails were present but not numerous. The barnacle cover increased along the western
pilings towards the mouth. The granite wall behind the pilings supported some algae cover (Fucus
sp. and green algae). Barnacle cover was heaviest on the metal pilings at the mouth of the site.
Mussels were observed only at the northwest corner of the site.
Breaching of the retaining wall along the southeast portion of the site has allowed
erosion into the aquatic zone, creating a small intertidal zone of rubble and fine-grained sediments.
Benthic Infauna
Benthic infauna was sampled in three locations in April 1993 (Table Al-2).
Nematodes accounted for >80% of the abundance at Stations RS-1 and RS-2 (98% RS-1, 84%
RS-2); C. capitata and oligochaetes were also numerically important components of the .fauna.
Abundances at RS-3 were low, made up primarily of the cirratulid polychaete Tharyx acut us and
nernatodes. Freshwater insects (chironomids, collembolans) were collected in low numbers.
Species richness at RS-1, near the mouth of the site, indicates that, at least seasonally, benthic
infauna can be relatively diverse in this site. The polychaetes present are primarily surface deposit
feeders, indicative of the stressed sediment conditions. The tube dwelling amphipod Mcrodeu-
toptts gryllotalpa, is commonly found associated with docks, algae and mussels (Bousfield 1973).
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Revere Sugar
Its presence in the infauna suggests it is present among the fouling organisms on the pilings and
bulkheads. The paucity of suspension feeders (e.g., bivalves) indicate that suspended particulates
or siltation rates are higher than suitable.
Sediment profile camera sampling at three locations in October 1994 revealed all sites
had homogeneous muddy sediments with some pit and mound topography, suggesting a
depositional environment (NAI and Diaz 1995). There was little evidence of bioturbation
(infaunal tubes, burrows, and voids). The Redox Potential Discontinuity (RPD) layer, an
indication of the depth to which sediments are oxidized, was located at less than 1 cm from the
sediment surface. These indicators suggest considerable environmental stress to the benthic
community. Benthic infauna samples collected in October 1994 contained an average of 9 taxa
per 0.12 m2, and an average of 483.2 individuals/m2, moderate in comparison to other Inner
Harbor stations (Table Al-3). Oligochaetes, cirratulid polychaetes, and nematodes were the most
abundant taxa, similar to previous collections. The epifaunal amphipod Microdeutopus gryllotalpa
and the motile sand shrimp Crangon septemspinosa were also collected. The benthic infauna
suggest the habitat is under environmental stress, with a pioneering or colonizing successional
stage of benthic community.
Lobster
An assessment of the lobster population was made in October 1994 using experimental
traps. A total of 0.2 CPUE (per trap-day) of sublegal-sized lobster (<83mm or 325 in CL) and
0.1 CPUE of legal-sized lobster were collected (Table Al-7). Males were twice as common as
females (NAI 1995b). Lobster CPUE was among the highest of those in the Mystic and Chelsea
Rivers, but an order of magnitude lower than offshore areas such as Meisburger 2 and 7 and
Boston Lightship. This is as expected, since benthic and sediment profile sampling indicated a
pioneer successional state with fine grained sediments and low densities of infauna. These less-
than optimal conditions may be offset by the presence of abandoned piers, which may provide
shelter for lobsters.
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Revere Sugar
As with Mystic Piers, finfish are likely to utilize the Revere Sugar site for shelter from
currents and predators, and for feeding. Species feeding indiscriminantly on the bottom would
encounter prey. Species that prefer to browse on hard substrates would find little food, while
winter flounder could spawn in this area, their preferred spawning habitat (sand) may not occur
at this site. Revere Sugar is located well below the head-of-tide, and so does not provide suitable
conditions for anadromous species to spawn. A fall 1994 gill net survey collected predominantly
rainbow smelt along with alewife, mackerel and winter flounder (Table Al-6). Total catch was
lower than other Inner Harbor, Outer Harbor, and offshore stations (NAI 1995a).
WETLAND RESOURCES
The Revere Sugar site is located within the Mystic River DPA (310 CMR 10.00).
Under Massachusetts wetlands regulations, most of the site would be designated as Land Under
the Ocean and have the potential to be significant to marine fisheries, storm damage prevention
and flood control. This site could provide both refuge (from currents and predators) and feeding
opportunities (primarily for demersal feeders). It is unlikely to provide spawning habitat for either
winter flounder, as it appeared to lack sandy sediments, or anadromous species (e.g., alewife), as
it is located well below the head-of-tide. Storm damage prevention and flood control are
enhanced at this site by the man made boundaries, although the seawall at the southern end of the
site is in disrepair and offers limited protection against exceptionally high tides. The greatest
potential for storm damage prevention and flood control occurs during low tides.
Intertidal resources include a debris strewn beach in the southeastern corner and the
granite walls and pilings surrounding the site. The beach could be categorized as Coastal Beach
but is not significant in the DPA. No natural intertidal features exist at this site.
Under federal regulations, the entire site is categorized as Tidal Waters. This resource
provides two functions not specifically identified by Massachusetts for DP As. The fine-grained
character of the sediments indicates the potential for sediment/toxicant retention and for nutrient
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Revere Sugar
retention/transformation exists. Aquatic diversity/abundance is moderate at this site and appears
to vary spatially, being highest at the mouth. Potential construction at this site may be more
sensitive because of its location on a river that has an anadromous fish run.
WILDLIFE
Wildlife use of the Revere Sugar site is expected to be similar to that described for
Mystic Piers (Section 2.3.1.1 of this evaluation).
THREATENED AND ENDANGERED SPECIES
No federally or state-listed threatened or endangered species are identified or
anticipated to occur within the boundaries of the Revere Sugar site (Lincoln 1993). Although the
state-listed common tern has been observed in Boston Harbor, no evidence of nesting activities
of this species was seen during a site visit on April 28, 1993.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources on or within 1000 feet of the
Revere Sugar site.
SOCIO-ECONOMIC/LAND USE
Revere Sugar, a site containing 6.5± acres in Charlestown, is currently under lease
from Massport by the MWRA which has constructed a water transportation facility .for the
ferrying of construction personnel to Deer Island. Construction personnel can park vehicles on
the Revere Sugar property before boarding the ferry to Deer Island. The lease for the ferry
operation runs to 1998. The dock is located on the west side of the property. The property is
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Revere Sugar
between two industrial sites and between the Mystic River and Medford Street. Across Medford
Street are residences and a cemetery. Land side access to the site from Moran Terminal is via
Terminal Street to Medford Street. These streets have mixed uses.
The neighborhood closest to Revere Sugar has a very low percentage of people below
the poverty line and a high median family income compared to other locations in Charlestown.
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Amstar
2.3.1.3 Amstar
The site is depicted on Figure Al-11.
SEDIMENT CHARACTERISTICS
Benthic samples collected at Amstar contained odorless, grey silty sediments. No
chemical analyses were performed on sediments from the Amstar site, but Station 3 from the
Revere Sugar berth was located approximately 300 feet from the mouth of the site and is assumed
to be representative of on-site conditions (see EIR/S Section 2.2). That station had a 73% silt-clay
component (Category HI). Chromium, copper and nickel all occurred at Category II levels;
arsenic, lead, zinc and PCBs were Category III concentrations. Total PAHs were among the
highest (46.41 ppm) observed during the 1992 berth area sampling. Benzo(b)fluoranthene,
benzo(k)fluoranthene, fluoranthene and pyrene each contributed more than 5 ppm to the total
concentration. Total petroleum hydrocarbons were 3540 ppm. Total organic carbon was 6.6%,
among the higher values observed during the berth sampling, suggesting that potential for
bioaccumulation of contaminants is lower at Amstar than other sites hi Boston Harbor. Zinc and
PAH uptake may be exceptions to this generalization, as these constituents were found at higher
levels at Revere Sugar Station 3 than at other berths.
WATER QUALITY AM) CIRCULATION
In general water, quality at this site is expected to be similar to conditions in the
Mystic River since there are no obstructions to flow. Again, the water quality classification is
Class SB. The character of the sediments observed within this site suggest that it may experience
the late summer hypoxia (August Effect). Water quality on the site may also be influenced by
two discharges on the southern and western banks which are most likely minor discharges
consisting of stormwater. There is also a NPDES discharge from Cambridge Electric in the
vicinity of the Amstar site (Menzie-Cura and Assoc. 1991).
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Amstar
Amstar opens directly on the Mystic River with no obstructions. Like Revere Sugar,
the northeast comer of the site may experience reduced flows or eddies during flood tides as
currents are diverted around the end of the wharf. This phenomenon would occur during ebb
tides at the northwest comer. The pilings supporting the eastern wharf and the floating dock slow
currents and contribute to sedimentation under the wharf.
AQUATIC RESOURCES
There are three types of intertidal habitat that occur at the Amstar site. Pilings and
vertical seawalls along the eastern side provide hard substrate that has been colonized by
barnacles, mussels and green algae. Beneath the ramp to the floating dock is a small, gently
sloping gravel-cobble beach. The cobble support green algae. The rest of the south boundary is
a rip-rap slope comprised of boulders that are heavily covered with Fitcus sp. There is little
Fucus sp. on the western rip-rap slope except at the mouth of the site. Along the western
boundary barnacles and periwinkles (Littorma sp.) were numerous; green algae was present above
and below the barnacle zone.
Benthic Infauna
Most of the site is submerged continuously. Differences in species composition at the
two sampling locations visited in April 1993 (Table Al-2) may reflect differences in circulation,
exposure and adjacent substrate conditions. Species present at Station AM-1 (dominants:
nematodes, Polydora cornuta, oligochaetes) are typically abundant harbor-wide. Total abundance
(18,287/m2) at AM-1 was moderate relative to other areas sampled. Station AM-2 supported low
abundances of several species, two of which (Crangon septemspinosa and harpacticoid copepods)
are motile. Sediment at this station was gelatinous, with an oily sheen.
Sediment profile camera sampling at three sites in October 1994 showed all had
homogeneous muddy sediments with some pit and mound topography, suggesting a depositional
or low energy habitat (NAI and Diaz 1995). The RPD layer was within 1.0 cm of the sediment
Al-72
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Amstar
surface, suggesting limited oxygenation of the sediments. There were few indicators of
bioturbation, such as the presence of infaunal tubes, burrows, and voids. Benthic samples from
one of the sites located near the 1993 sampling station AM-1 revealed abundance levels that were
the highest of all Inner Harbor stations (1,912.5/m2 Table Al-3) but an order of magnitude lower
than 1993 sampling at AM-1 (Table A1-2). The dominant taxa were opportunistic polychaetes
(Polydora cornuta, Streblospio benedicti) and nematodes, similar to AM-1; together these three
taxa composed 85% of the infaunal population. The benthic community seems to be one under
environmental stress, characterized by pioneering or colonizing benthic infauna.
Finfisfa
Finfish could utilize this area for refuge from predators, particularly among the pilings
at any tide and among the Fucus sp. of the southern boundary during high tides. The entire site
could provide refuge from peak currents due to its orientation perpendicular to the channel.
Anadromous fish could use the site for this purpose. Subtidal regions could provide food
resources for demersal browsers. Intertidal food resources are limited except for fish that browse
green algae.
The Amstar site does not provide spawning habitat for anadromous species as
freshwater input is limited to three drainage pipes. Winter flounder spawning opportunities are
limited since the site's sediments are not sandy.
WETLAND RESOURCES
Amstar is located within the Mystic River DPA (310 CMR 10.00). The site is
primarily Land Under the Ocean, under Massachusetts regulations, and is considered to be
significant to marine fisheries, storm damage prevention and flood control. As described under
Aquatic Resources, the Amstar site could provide both refuge (from predators and currents) to
many fish species and feeding opportunities (primarily demersal species). It is unlikely to provide
important spawning habitat.
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Amstar
Man-made features at Amstar were designed to contribute to storm damage prevention
and flood control. Surrounding land elevations are several feet above mean high water. The rip-
rap slopes along the southern and western boundaries are effective in dissipating currents and
waves.
The intertidal area under the floating dock ramp could be categorized as Coastal
Beach, but is not significant in the DPA.
The entire site is classified as Tidal Waters, under federal regulations. The fine-
grained sediments found at this site, in conjunction with nearby sediment sampling, suggest that
this site has the potential for sediment/toxicant retention and for nutrient retention/transformation.
Benthic fauna were moderate in abundance and diversity compared to other sites examined. As
anadromous fish species are known to transverse the Mystic River, it is possible that Amstar could
be used by them as well.
WILDLIFE
Wildlife use of the Amstar site is expected to be similar to that described for Mystic
Piers site.
No federally or state-listed threatened or endangered species are identified or
anticipated to occur within the boundaries of the Amstar site. The state-listed common tern has
been observed to nest in Boston Harbor. No nesting activities were observed during field
investigations on this site on April 28, 1993.
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Amstar
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no listed historical and archeological resources on or within 1000 feet of
the Amstar site.
SOCIO-ECONOMIC/LAND USE
Amstar is an industrial site containing approximately 20 acres in Charlestown. It is
currently available for sale, although there are several industrial tenants. One tenant runs a sand
and gravel operation and uses the dock for material transfer. The site is in the City's Maritime
Economy Reserve Zone which is geared to water dependent activities. It is surrounded by
industrial uses to the east and west. Across Medford Street from the site are residences and a
park. Access to Amstar is the same as that to Revere Sugar. Demographic characteristics are
similar to those described for Revere Sugar.
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Cabot Paint
23.1.4 Cabot Paint
The site is depicted on Figure Al-12.
SEDIMENT CHARACTERISTICS
Benthic samples collected at Cabot Paint contained odorless, gray silly sediments. No
chemical analyses were performed on sediments from Cabot Paint site, but Station 1 of Eastern
Minerals was located approximately 2000 feet from the Cabot Paint site (see Section 2.2 of the
DEIR/S). This station had a 66.5% silt-clay component; arsenic, chromium, lead, mercury, zinc
and PCB concentrations all occurred at Category n levels. Total PAHs occurred at Category ffl
levels (11.38 ppm), and benzo(b)fiuoranthene contributed 3.67 ppm to the total concentration.
Total organic carbon was 3.6%, suggesting that some bioaccumulation of contaminants may likely
occur.
The ACOE conducted chemical sampling in 1986 (ACOE 1988) at eight (8) stations
(A through H) in Chelsea Creek. Station G was located in the vicinity of the Cabot Paint site.
It is assumed for this level of site evaluation that the chemical constituents at Station G should
be similar to that of the Cabot Paint site. Station G had a sandy organic clay composed of 68%
fine grained material with a moderate chemical oxygen demand (102,000 ppm). The only
contaminant detected in high concentrations was lead at 283 ppm (Category HI). Levels of
mercury (1.14 ppm), zinc (276 ppm) and chromium (185 ppm) were present at Category II.
WATER QUALITY AND CIRCULATION
The Chelsea Creek is classified as SB waters by the MADEP. Cabot Paint opens
directly into the Chelsea Creek, but the wooden pilings on the north of this site slow currents and
contribute to some sedimentation hi the vicinity of the pilings.
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Cabot Paint
Dissolved oxygen readings collected in April 1993 ranged from 8.6 - 9.0 mg/L at
water temperatures ranging from 6.6-8.2°C. Salinity data collected on that date ranged from 22.6-
28.4 ppt at low tide, indicating the influence of freshwater inputs.
AQUATIC RESOURCES
The intertidal habitats within the Cabot Paint site vary and include 1) a sloping rip-rap
embankment on the north side, 2) gravel beaches on the northeast and northwest sides, 3) the
wooden pilings on the north side, 4) a wooden bulkhead and concrete slab on the northwest side,
5) an abandoned boat ramp on the northwest end, and 6) abandoned barges and boat on the
northwest end. Microalgae cover (Fucus sp. and green algae) varied throughout the site's intertidal
areas. Limited cover was observed on the rip-rap, while approximately 40% of the gravel beach
was covered. The abandoned boat ramp was also covered with Fucus sp. The wooden pilings
were completely covered with barnacles and Fucus sp. and the wooden bulkhead had some of
these species.
Benthic Infauna
The composition of the benthic infauna from samples collected in April 1993 is shown
in Table Al-2. The two sampling locations may reflect the differences in substrate conditions,
circulation, and exposure. Station CP-1 was located in the vicinity of the submerged pilings,
where the most abundant species were Oligochaeta, S. benedicti, and Nematoda. The total
percentage composition of these three species was 59% at Station CP-1. Total abundance at this
station (of 9,202 individuals/m2) was moderate when compared with the other areas sampled. At
station CP-2 (located in an open area between the pilings) the most abundant species were S.
benedicti and Nematoda. This station had a total abundance of 3,354/m2, low when compared
with the other stations. The total percentage composition of these three species was 96% at
Station CP-2. Species richness at both stations was low (5-9).
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Cabot Paint
Sediment profile camera sampling was conducted at three stations within the Cabot
Paint site (NAI and Diaz 1995). Silty sediments with an RPD layer located at less than 1 cm
from the sediment surface occurred at all three sites. These parameters indicate a low-energy
habitat with reducing conditions near the sediment surface. Microalgal mats were observed at the
sediment interface at the southern edge of the site (Station 1) and at one of the stations in the
central portion of the site (Station 2). There was no indication of infauna inhabiting the sediment
surface or at depth. A benthic sample from the southwestern part of the site collected one taxon.
The opportunistic polychaete Polydora cornvta was the only organism collected, with an
abundance of 25/m2. Results indicate this was one of the most depauperate areas of the Inner
Harbor (Habitat n, Table Al-3). Mound and pit topography was observed in the southeastern
portion of the site, indicating a low energy environment. Evidence of bioturbation (infauna tubes,
burrows) occurred only in the central and northern portion of the site. A total of 6 taxa were
collected in the 0.04m2 sample (Habitat m, Table Al-3). Opportunistic polychaetes Polydora
cornuta and Streblospio benedicti were the most abundant taxa, and composed two-thirds of the
total abundance. The total number of organisms, 375/m2, was low in comparison to other Inner
Harbor Stations. All abundances hi 1994 were an order of magnitude lower than those observed
in 1993 (Table Al-2).
The ACOE NED collected frafish samples by gillnet in July and November, 1986
during a 48-hour effort on two different sampling days in the Chelsea Creek. The dominant
finfish species found in the July sampling effort were rainbow smelt and alewife. In the
November sampling effort, no fish were caught. Given the limited amount of data for
comparison, no real conclusions can be drawn at this tune. Finfish could use the wooden pilings
and Fucits sp. for shelter from predators during high tide. The sandy substrate in the Chelsea
Creek may provide spawning habitat for winter flounder (ACOE 1988).
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Cabot Paint
WETLAND RESOURCES
Cabot Paint is located within the Chelsea River DPA and primarily contains Land
Under the Ocean, as defined under Massachusetts Wetlands Protection regulations (310 CMR
10.00). Land Under the Ocean is considered to be significant to marine fisheries, storm damage
prevention and flood control. The sloping rip-rap embayment on the north side of the site was
designed for storm damage prevention and control. The gravel beaches could be categorized as
Coastal Beach, but this designation is not significant in the DPA.
Many species of marine fishes, including anadromous fish, may inhabit DP As.
Anadromous fish such as rainbow smelt and alewife are known to traverse the Chelsea Creek.
As described in the Aquatic Resources section, the Cabot Paint site could provide both shelter
from predators and feeding opportunities for these fish species. This site may also provide spawn-
ing habitat for winter flounder.
The entire site is classified as Tidal Waters under federal regulations. The fined-
grained sediments and the results of the samples analyzed indicate that this site has the potential
for sediment/toxicant affinity and nutrient retention. Benthic infauna species diversity was low-
moderate and species richness was low at this site.
WELDLIFE
On-site wildlife resources appear limited, and very similar to the Mystic Piers site.
THREATENED AND ENDANGERED SPECIES
No federally or state-listed threatened or endangered species are identified or expected
to occur within the vicinity of the Cabot Paint site.
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Cabot Paint
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no sites or structures of historical, architectural or archeological significance
as defined by MHC or the National Historical Preservation Act, as amended.
SOCTO-ECONOmC/LANP USE
This site, containing 6.5± acres off Marginal Street in Chelsea, is a mixed use parcel,
fully occupied by industrial tenants and a major car rental storage facility. The current owner has
'
demolished some of the industrial buildings on site and adapted the remaining buildings to support
l
several industrial uses. The wooden bulkhead along Chelsea Creek has deteriorated and currently
poses navigation problems for vessels traversing Chelsea Creek. A commuter ferry service to
Boston operated briefly out of this location during 1990 in an effort to reinstate ferry service from
this site. The service was discontinued.
The City of Chelsea evolved from a summer resort community to a residential suburb
of Boston. A major fire in 1908, in which over 17,000 residents were left homeless, changed the
landscape permanently. The Chelsea which emerged from the fire was primarily commercial with
manufacturing and shipping facilities. Several of the industries have closed hi recent years
succeeded by service and distribution operations. The population of Chelsea is 28,710 and is 70%
white with a high percentage also reporting Hispanic origin. The median family income is
$29,039. High end residential use has been developed on property surplused by the military,
contrasting with more modest housing in densely populated sections of Chelsea.
Access to this site over land is via 1-93 to the Tobin Bridge to Chestnut Street, and
from Chestnut south to Williams Street, then east on Williams to Marginal Street.
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Little Mystic Channel
2.3.1.5 Little Mystic Channel
The site is depicted on Figure Al-13.
SEDIMENT CHARACTERISTICS
No samples were collected within the site boundaries for sediment characterization,
but Stations 2 and 3 at the Mystic Pier sites are in close proximity to the Little Mystic Channel
and should represent probable sediment conditions. The sediment texture was predominately fine
grained with a range of 76.3% - 78.4% silt-clay (Category n). Bulk sediment metals test results
showed that at Station 2, arsenic, chromium, copper, lead, mercury, and zinc all occurred at
Category H levels (Appendix C). At Station 3, arsenic, lead and zinc were found to be Category
IE, and cadmium, chromium, copper, and mercury were found to be Category II concentrations.
Total PAHs ranged from 5.23 and 29.75 ppm at Stations 2 and 3 in Mystic Pier 1. Station 3
contained the highest levels of metals of the three stations at this site. At Station 3, benzo(a)-
anthracene and benzo(a)pyrene, chrysene, fluoranthene and pyrene were present in concentrations
above 4 ppm. But at Station 2, only fluoranthene was above 5 ppm. At Mystic Pier 1, total
petroleum hydrocarbon concentrations were among the highest observed during the 1993 berth
area sampling. At Mystic Pier 1, there have been approximately twelve minor oil spills (U.S.
Coast Guard, Marine Safety Office, letter dated May 13, 1992). This may have influenced the
concentration of PAHs and TPHs at this site. PCBs were present at Category in concentrations
at Stations 2 and 3. Total organic carbon ranged from 2.1-4.9% at both stations. This is an
average value, indicating that there are moderate levels of food resources for benthic deposit
feeders, suggesting that some bioaccumulation of contaminants may be occurring.
WATER QUALITY AND CIRCULATION
The water quality of the Little Mystic Channel is influenced by tidal exchange, the
six discharge pipes that were observed on the north side of the site, and a Combined Sewer
Overflow (CSO). These storm drainage pipes add urban runoff pollutants (e.g., oil and grease,
Al-81
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Little Mystic Channel
detergents etc.) into the Channel. There is one CSO, the Chelsea Street Extension outfall, which
discharges directly to the Little Mystic Channel on the south shore. The currents in Little Mystic
Channel are primarily tidally driven. The Little Mystic Channel is classified as SB water by the
MADEP. Dissolved oxygen readings collected in April 1993 ranged from 9.0-9.4 ppm. As
temperatures peak in August, available dissolved oxygen levels diminish within Boston Harbor
and cause a corresponding depression in biological activity at the sediment water interface (August
Effect). This oxygen depletion contributes to a significant faunal depletion on a cyclic basis
(Hubbard and Bellmer 1989). Salinity data collected in April 1993 ranged from 16.8-28.9 % at
low tide, indicating the influence of freshwater inputs to the Harbor. Little Mystic Channel flows
directly into the Main Ship Channel, but the Mystic-Tobin bridge pilings slow currents and con-
tribute to some sedimentation in the vicinity of the pilings.
AQUATIC RESOURCES
The intertidal habitats within the Mystic Channel vary and include, 1) vertical granite
walls on the north and south side which contain approximately 80% Fucus sp. and a one-inch
layer of barnacles; 2) sloping rip-rap embankment on the west side which is covered with Fucus
sp. and green algae; 3) wooden bridge pilings on the eastern side which were covered with
periwinkles (Littorina sp.), barnacles and green algae; 4) submerged logs and boat on the north
side; 5) a metal bulkhead which was covered with Fucus sp., heavy barnacle settlement, and some
mussels approximately 50 feet from the bridge; 6) a sandy/gravel beach on the south side which
was sparsely covered with green algae; and 7) a rock ledge beach on the north side which was
covered with Fucus sp.
Benthic Infauna
Composition of the benthic infauna at the site in April 1993 is shown in Table Al-2.
The four sampling locations may reflect the differences in substrate conditions, circulation and
exposure. Station LMC-2, located in the vicinity of the sloping rip-rap embayment, was most
diverse in terms of species composition. The total abundance of organisms was 27,907 individu-
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Little Mystic Channel
als/m2 at this station, a moderate level relative to other harbor areas sampled. Oligochaeta was
the dominant taxon and had an abundance of 13,717/m2. Station LMC-1 supported low abundance
of two taxa, Tharyx acutus (86/m2) and S. benedicti (43/m2) at extremely low levels compared to
all the other sites for these taxa. Station LMC-3 supported a low abundance of 10 taxa, the most
abundant being Nematoda and S. benedicti. Station LMC-4 had a low abundance of six taxa, the
most abundant being Nematoda. The sediment samples collected at this site for benthic infauna
observations were fine and grayish-black in color with a mild sulfur odor.
Sediment profile camera sampling in 1994 at four locations showed homogeneous mud
sediments throughout the area with evidence of mound and pit topography, indicating a
depositional environment (NAI and Diaz 1995). The depth to the RPD layer ranged from 0.2-1.0
cm below the sediment surface, suggesting varying degrees of sediment oxygenation, and thus
environmental perturbation, in the area. There were low numbers of infauna tubes at the sediment
surface, but no other indicators of bioturbation. Benthic samples collected in October 1994
revealed a depauperate benthic community. Numbers of taxa (3/0.12 m2) and total abundance
(16.6/m2) were among the lowest observed in the Inner Harbor (Table Al-3). The surface
dwelling bivalve Midinia lateralis, the hydrozoan Obelia sp., and amphipod Gammarus
lawrencianus were the only species that were collected; none of these species was collected in the
1993 study (Table Al-2).
Lobster
A total of 0.6 sublegal lobsters and 0.6 legal-sized lobsters were collected per trap-day
in the fall collection in 1994 (Table Al-7). The total CPUE was higher than that recorded from
the Mystic and Chelsea Rivers, similar to that at Harbor Stations such as the nearby Inner
Confluence and Logan 02, but much lower than offshore stations such as Meisburger 2 and 7.
Males were more abundant than females (NAI 1995b). Little Mystic Channel had the highest
recorded legal lobster catch (0.6 per trap day, all males) of all stations sampled. This may be a
result of the presence of abandoned piers, which may provide shelter. Abundances of
invertebrates were low to moderate, and were composed mainly of small worms such as
oligochaetes and nematodes, which are not preferred lobster prey items.
Al-83
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Little Mystic Channel
The dominant finfish species recorded in the Main Ship Channel include winter
flounder, rainbow smelt, and alewife (ACOE, NED 1988). There probably is movement of at
least some of these species in and out of the Little Mystic Channel. Gill net collections in
October 1994 in Little Mystic Channel captured low numbers of rainbow smelt, Atlantic tomcod,
alewife, cunner and butterfish'(Table Al-6). Trawls in the Inner Confluence area made at the
same time collected moderate catches of winter flounder, windowpane, and rainbow smelt (Table
Al-4). Finfish could use the wooden bridge pilings, submerged logs and boat and Fucus sp. for
shelter from predators during high tide. The predominant sandy/silt sediment present at this site
provides suitable habitat for whiter flounder. There was also a fair supply of C. capitata in part
of the channel in 1993 (1892/m2 at Station LMC-2); these are consumed by winter flounder
according to Haedrich and Haedrich (1974). However, 1994 sampling showed little evidence of
food resources for higher trophic levels.
WETLAND RESOURCES
Little Mystic Channel is located within the Mystic River DPA (310 CMR 10.00). The
site is primarily Land Under the Ocean, under the State regulations, and is considered to be
significant to marine fisheries, storm damage prevention and flood control. The vertical granite
wall on the north and south side, together with the sloping rip-rap embayment on the west of the
site, were all structures designed for storm damage prevention and flood control. Significance to
I
marine fisheries is discussed above.
Anadromous fish are known to traverse the Main Ship Channel and there may be
movement into the Little Mystic Channel. As described in the Aquatic Resources section, the
Little Mystic Channel could provide both shelter from predators and feeding opportunities for
several fish species. This site might also provide spawning habitat for anadromous species.
Al-84
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Little Mystic Channel
The entire site is classified as Tidal Waters under federal regulations. The fined-
grained sediments results of the samples analyzed at Mystic Pier, which is in close proximity to
Little Mystic Channel, indicate that this site has the potential for sediment/toxicant affinily and
nutrient retention. Benthic infauna were moderately diverse in species composition at one station
and showed low abundance at the other three stations sampled at this site.
WILDLIFE
Wildlife use in the Little Mystic Channel is expected to be similar to that described
at the Mystic Pier site.
THREATENED AND ENDANGERED SPECIES
No federally or state-listed threatened or endangered species are identified or expected
to occur within the vicinity of the Little Mystic Channel.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources at the Little Mystic Channel
site.
SOCIO-ECONOMIC/LAND USE
This little-used channel in Charlestown is surrounded by a mixture of land uses
including residential, recreational and maritime-industrial. Adjacent to the site are the Charles
Newtowne public housing project, a City of Boston playground, the Charlestown High School
recreational field and Mystic Pier 1. The channel provides a visual buffer between the residences
to the south and the marine terminal to the north. A public boat ramp is located on the north side
Al-85
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Little Mystic Channel
of the channel. However, this ramp has not received the use anticipated when it was installed in
the early 1970s. Demographic characteristics of this area are similar to those described at the
Mystic Pier site.
Marine access to this site is constrained by the 12 foot vertical clearance under the
Little Mystic Channel Crossing at the mouth of the channel. Landside access to this site is via
Terminal Street from Moran Terminal.
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Reserved Channel
2.3.1.6
Reserved Channel
The site is depicted on Figure Al-14. Two areas in the Reserved Channel are being
evaluated as candidate sites for disposal, Areas A and B, respectively.
Area A—This area is located at the mouth of the inlet on the inner side of the bridge
(away from open water). It is approximately 8.9 acres in size with water depths
ranging from 6 to 12 feet MLW. A floating dock and the yacht club are located in
this portion of the site. The passage under the Summer Street Bridge is 40 feet in
width. Northwest of the bridge is a vertical granite wall approximately 50 feet in
length. Continuing west-northwest, the granite wall is replaced by a metal bulkhead.
On the far northwestern end of the bulkhead are some abandoned wood pilings and
an old floating dock. On the southwestern side of the site from the bridge is a sloping
rip-rap embankment for approximately 50 feet. From this rip-rap toward the neck are
discarded concrete slabs and trash material. West of the trash material are wooden
pilings and behind the pilings is a vertical granite wall.
AreaB—This portion of the site extends from the neck on the northwest toward the
tip of the peninsula. It is approximately 7.7 acres in size with water depths ranging
from 0 to 16 feet. A steel bulkhead extends for approximately 75 feet. Continuing
along the western tip and along the southwestern side of the inlet is a sloping rip-rap
embankment. Between the bulkhead and the rip-rap is a pile of rubble. On the south-
western side toward the neck the rip-rap is replaced by a granite wall, which is
fronted by a rocky beach. In front of the rocky beach are one or two sunken boats
and some abandoned pilings. In the middle of the tidal area is a floating lobster pot
dock.
SEDIMENT CHARACTERISTICS
Benthic samples collected at the Reserved Channel contained odorless, gray-black
clay/silt sediment. No chemical analyses were per formed on these sediments, but Station 3 of
Al-87
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Reserved Channel
the Boston Edison Intake was located approximately 1000 feet from the Reserved Channel Area
B (see Section 2.2 of the EIS). This station had a 66.2% silt-clay component (Category II) and
indicated PCB and PAH levels at Category HI. Fluoranthene, ideno(l,2,3-cd)pyrene, and pyrene
contributed more than 50% to the total PAHs concentrations. Cadmium, Lead, and Nickel were
found at Category n at this station. Total organic carbon was 13%, the second-highest value of
all the sites analyzed for TOC. This indicates that the potential for bioaccumulation at the
Reserved Channel Area B is lower than other sites in the Boston Harbor. The total petroleum
hydrocarbon at this station was 4270 ppm.
The ACOE conducted chemical sampling during 1986 at four stations (A, B, C, and
D) in the Reserved Channel. Station A was located hi the western end of the Reserved Channel
close to Area B. At Station A an 18-23 cm core section was analyzed. It had an 18.2 cm layer
of black organic clay. This upper organic clay consisted of 93% fine grain material with a
moderate chemical oxygen demand (79,000 ppm). Lead was the only chemical constituent present
at Category ffi concentrations (221 ppm). Mercury (1.48 ppm), zinc (264 ppm), chromium (186
ppm), and nickel (58 ppm) were-detected at Category II levels.
PCB samples were collected at 8 stations by Boston Survey Consultants in November
1982, from the Reserved Channel west of Summer Street Bridge within Area A (MADEP-Boston
Files, 1983). PCB concentrations at all eight stations occurred at Category HI and ranged from
1.0-34.5 ppm.
WATER QUALITY AND CIRCULATION
The water quality of the Reserved Channel is influenced by the three combined sewer
overflows (CSO) observed approximately 700 feet northwest of Pappas Street, at Summer Street,
and at I Street. These CSOs can add urban runoff pollutants (e.g., PAHs, nutrients, detergents,
bacteria, etc.) into the Channel. Boston Edison has a NPDES discharge pipe in the vicinity of
Summer Street; theNPDES permit limits the thermal influence on surface waters in the Reserved
Channel.
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Reserved Channel
The Reserved Channel flows directly into the Main Ship Channel. The Summer Street
bridge pilings slow and deflect currents and contribute to some sedimentation in the vicinity of
the pilings.
The Reserved Channel is classified as SB Water by the MADEP. In bolh Areas A
and B, dissolved oxygen readings collected in April ranged from 8.4-8.7 ppm and 6.8-8.9 ppm
respectively. As temperatures peak in August in Boston Harbor, available dissolved oxygen levels
can diminish and cause a corresponding depression in biological activity at the sediment water
interface (August Effect). This oxygen depletion contributes to a significant faunal depletion on
a cyclic basis (Hubbard and Bellmer 1989). Salinity data collected in April 1993, ranged from
27.0-31.2 ppt at Area A and 23.4-33.4 ppt at Area B during low tide, indicating the influence of
freshwater inputs to the Harbor.
AQUATIC RESOURCES
The intertidal habitats within the Reserved Channel include:
Area A: Wooden bridge pilings and a floating yacht club dock were sparsely covered
with green algae. A vertical granite wall on the northwest side of Summer Street was
covered with approximately 20% of algae. A metal bulkhead on the northwest side
was covered with green algae and barnacles. Sloping rip-rap embankment on the
southwest side was covered with Fucus sp., barnacles, Littornia sp., and green algae.
Some concrete slab and trash material was present which had no visible growth; there
were some abandoned wooden pilings and an old floating dock on the far northwest-
ern side.
Area B: A steel bulkhead on the northwest side was approximately 90% covered with
barnacles. A sloping rip-rap embankment on the western tip and southwestern side
was moderately covered with Fucus sp., Enteromorpha (tubular green algae), and
other green algae. A granite wall on southwestern side towards the narrow neck had
moderate growth of Fucus sp., Ulva sp., and barnacles. A rocky beach in front of the
Al-89
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Reserved Channel
granite wall was sparsely covered with Littornia sp., Fzicus sp., and green algae.
There were also sunken boats, abandoned pilings and a floating lobster dock present.
Benthic Infauna
The composition of the benthic infauna from 1993 collections is shown in Table Al-2.
The four sampling locations may reflect the differences in substrate conditions, circulation and
exposure. Stations RC-1 and RC-2 were located in Area A and RC-3 and RC-4 located in Area
B.
Area A: Station RC-2 was located in the vicinity of the Granite wall on the
southwestern side of Area A, had the most diversified species composition.
Oligochaeta and S. benedicti was the two most abundant taxa (15,480/m2 and
1548/m2, respectively) of all the sites sampled. The total abundance was 21,156/m2
at Station RC-2 which was moderate relative to other areas sampled. Station RC-1
supported low abundance of seven species, the most abundant being Oligochaeta
(2451/m2). Oligochaetes were moderately abundant at this site compared with all the
other sites. The total abundance was 3,096/m2 at Station RC-2, and was low relative
to other areas sampled.
Area B: Station RC-3, located in the vicinity of the lobster dock, supported very low
abundance of four taxa, the most abundant being S. benedicti (215/m2). At Station
RC-4 Oligochaeta (26,574/m2), Corophium insidiosum (2580/m2), and Nematoda
(16,641/m2) were the most abundant taxa. The first two taxa occurred in higher
abundances at this site than any of the other sites sampled. The total abundance at
Station RC-4 was 49,837/m2, fairly high relative to the other areas sampled.
The sediment samples collected at this site for benthic infauna observations were
odorless, clay/silt, and grayish black in color.
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Reserved Channel
Samples were collected in October 1994 at one location in Area A and two locations
in Area B. As mere were no substantial differences among the three stations, abundances were
averaged for the purpose of this assessment. A total of 1,041 individuals/m2, representing 17 taxa
in the three 0.04 m2 samples was collected (Table Al-3). The species richness and abundance
were among the highest in the Inner Harbor, although much lower than most of the stations
sampled in 1993 (Table A1-2). The most abundant species were small, opportunistic polychaetes
such as Leitoscoloplos robustus (375/m2) and the soft-shell clam Mya arenaria (158/m2); both
were also collected in 1993 (Table Al-2).
Lobster
An assessment of the lobster population was made in October 1994 using experimental
traps (NAI 1995b). A total of 1.4 lobsters per trap-day were collected, of which 1.2 were
sublegals and 0.2 were of legal size (Table Al-7). The numbers of lobsters collected were
moderate in comparison to other areas sample in Boston Harbor, higher than river habitats, but
lower than offshore habitats. The wooden pier pilings may provide additional shelter for lobster.
CSO outfalls may enhance nutrient concentrations, resulting in high abundances of food resources.
However, the dominant benthic species were small, surface-swelling polychaetes, which are not
a preferred food source.
Finfish
Gill net collections in October 1994 in the Reserved Channel were the highest of all
stations sampled hi Boston Harbor. An average of 96.7 fish were collected per 24-hour set,
composed mainly of blueback herring and alewife (Table A1-6). Recreationally important species
such as striped bass, American shad, bluefish and rainbow smelt were also collected in low
numbers. These species are typical pelagic species, whose capture is more likely a random event
rather than an indication of habitat value.
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The dominant finfish species in the Main Ship Channel are flounder, rainbow smelt,
and alewife. There may be movement of these species into the Reserved Channel. Finfish may
use the wooden bridge pilings, floating dock, and Fvcus sp. for shelter from predators during high
tide. The Reserved Channel may provide spawning habitat for winter flounder, although it lacks
the preferred substrate.
WETLAND RESOURCES
Areas A and B of the Reserved Channel are not located within a Designated Port Area
(310 CMR 10.00). The site is primarily Land Under the Ocean under Massachusetts Wetlands
Protection regulations (310 CMR 10.00); this classification is considered to be significant to the
protection of marine fisheries, which are discussed above. Nearshore areas of Land Under the
Ocean such as Areas A and B are likely to be significant to storm damage prevention and flood
control. The vertical granite wall and bulkhead, together with the sloping rip-rap embankment
j
at the site, were all structures designed for storm damage prevention and flood control. Nearshore
areas of Land Under the Ocean also provide important food for birds; for example, waterfowl can
feed on the algae. The sloping rip-rap embankment and the rocky beach (Coastal Beach) at this
site were covered with algae.
The entire site is classified as Tidal Waters under federal regulations. The fined-
grained sediment and chemical levels in the samples analyzed show that this site has had an
affinity for toxicant and nutrient retention. Benthic infauna were moderately diverse in species
composition at two stations and showed low abundances and species richness at the other two
stations sampled at this site.
WILDLIFE
Wildlife use at the Reserved Channel is expected to be similar to that described for
Mystic Piers (Section 2.3.1.1 of this evaluation).
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THREATENED AND ENDANGERED SPECIES
No federally or state-listed threatened or endangered species are identified or expected
to occur within the vicinity of the Reserved Channel.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources at the Reserved Channel site.
SOCIO-ECONOMIC/LAND USE
This channel is generally surrounded by industrial and office uses in South Boston.
There is a sewer outfall at the southerly end of the Channel which would require relocation if this
area were to be filled. There is a yacht club immediately adjacent to the Summer Street Bridge,
and a passive water viewing area has been created for the general public to use on the west side
of the channel. This viewing area is not 6(f) land because it was not purchased or improved with
funds from the Land and Water Conservation Act (16 USC 460). As noted earlier there is a float-
ing lobster pot dock in the middle of Area B; the extent of its use is not known.
While the South Boston peninsula was settled early in Boston's history, much of the
land area between the subject site and Boston Harbor was created by filling the tidal flats. The
filled land supported maritime shipping and railroad terminal uses. The area to the south of the
channel has traditionally been a densely populated, predominantly residential neighborhood. The
population of South Boston is 29,464 of which 96% is white. The median family income in the
subject area is $34,200.
Marine access to this site is restricted by the vertical clearance on the Summer Street
Bridge over the Channel. That clearance is only 6 feet at high tide. The most direct landside
access would be 1-93 south to Summer Street and then east to the Reserved Channel.
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Environmental Consequences: Shoreline Sites
233. Environmental Consequences of Use of Shoreline Sites for
Dredged Material Disposal
Two different disposal scenarios have been evaluated for each of the shoreline sites.
The former pier areas (Amstar, Cabot Paint, Mystic Piers and Revere Sugar) and Little Mystic
Channel could be filled either to mean low water (including cap) or to fastland. Reserved
Channel would be filled either only in the westernmost end (to +6 ft MLW) or west from the
Summer Street Bridge (maintaining subtidal conditions in the area near the bridge). Disposal in
these areas would require the construction of a bulkhead to isolate the disposal operations from
the harbor waters. In the scenarios where final elevation would be mean low water, the disposed
silt would be capped and then the bulkhead would be clipped off to mean low water.
I
For ease of presentation, the different types of impacts are discussed generically and
site-specific information on shoreline sites is presented at the end of each subsection.
Direct Impacts
In either fill scenario, the dredged materials placed in shoreline sites would sequester
existing sediments. Although the chemical constituents of the surface sediments at many of these
sites have not been determined, areas adjacent to each site have been tested. It is likely that
j
metals, PCBs and PAHs are elevated to undesirable levels in Amstar, Cabot Paint, Little Mystic
Channel, Reserved Channel and Revere Sugar. Mystic Piers is likely to contain elevated levels
of metals and PAHs. Covering these sediments would provide the benefit of preventing their
reintroduction into the waters of Boston Harbor and would prevent further exposure of biota that
might utilize these areas. It would not prevent reintroduction of contaminants from other sources
in the partial fill scenario.
Partial fill. Under the partial fill scenario, subtidal habitat would be temporarily
impacted and removed from productivity. Closure of the site would return it to aquatic habitat,
but in an altered form. Both depth and substrate character would differ from existing conditions.
The footprint of each site is listed on Table Al-8. The quantity of habitat affected would be the
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Environmental Consequences: Shoreline Sites
smallest for Mystic Piers, slightly higher for Amstar and Revere Sugar, higher for Cabot Paint and
substantially higher for Little Mystic Channel and Reserved Channel. The cap, probably parent
material from the channel deepening, would not be suitable for colonization by benthic organisms
immediately. Dense clay does not generally support benthic infauna, but this area would be likely
to experience sedimentation. Once the sedimentation took place, benthic infauna typical of the
Inner Harbor would colonize the area. Conversion of the site from siibtidal to intertidal habitat
would be unlikely to increase its benthic productivity. Reduction in depth could make the area
somewhat more useful for juvenile finflsh as shallower conditions have been found to provide
refuge from predators in the absence of other, preferred (e.g., salt marsh, eelgrass bed) refuge.
Such shallow water refuge is limited within Boston inner harbor. This area would be available
during most of each tidal cycle, except for a limited period around each low tide.
Fastland. Filling the Amstar, Cabot Paint, Mystic Piers or Revere Sugar pier area to
the elevation of the adjacent land would result in the permanent loss of subtidal habitat (Table Al-
8). The bulkhead enclosing the dredged material would replace a portion of the hard substrate
habitat presently provided by pilings and bulkheads along the interior of each site. It is not
proposed to fill any of Reserved Channel to fastland.
Indirect Impacts - Water Quality Effects
Construction of the bulkhead would require driving sheetpile into the existing
substrate. While this activity would suspend some of the surface sediments into the water column,
the effect on water quality is expected to be minimal.
Harbor water trapped behind the bulkhead would be pumped out before disposal of
silts was initiated. Once most of the water was discharged back into the harbor, the remainder
would be filtered to prevent mobilization of silts from the disposal site. Because the site would
be enclosed before disposal took place, individual disposal events would not impact water quality
with the exception of occasional minor spills as silt was transferred from the barge to the disposal
site.
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Environmental Consequences: Shoreline Sites
Indirect Impacts - Site Stability
Long-term water quality effects could arise from two sources - dewatering of the
sediments and failure of the cap or bulkhead, In the partial fill scenario, no attempt would be
made to dewater the silt in place, with the exception of the consolidation that was caused by
placement of the cap. In the fill-to-fastland scenario, water would be drained from the site
through wicks in the bulkhead. The wicks would filter particulate material, but would not
completely control dissolved contaminants from being released into Boston Harbor. The elutriate
tests on surface sediments from the channels conducted by the U.S. Army Corps of Engineers
provide an approximation, of the levels of contaminants that could be released through the wicks.
These tests showed that mercury, copper and PCBs had the highest potential of being released.
Cap failure could occur at some of the sites adjacent to active piers. Although bottom
currents in the inner harbor are of insufficient speed to resuspend a sand cap and waves do not
develop sufficient height to affect the substrate in the inner harbor, cargo vessels making turns,
docking and departing docks use more power than when underway in the shipping channels.
These same conditions could affect the long-term stability of the bulkhead, although this effect
would be taken into consideration during site design. This effect has the greatest potential to
occur at Amstar, Revere Sugar (these two sites are adjacent to the active Revere Sugar terminal),
Mystic Piers (adjacent to Mystic Piers 2,49 and 50, as well as the bend at the Inner Confluence),
and Cabot Paint (parallel to the main channel of Chelsea Creek). Little Mystic Channel could be
exposed to activities at the active Mystic Pier 1, but site geometry would allow more flexible
design considerations to avoid this effect. Reserved Channel would not be exposed to the effects
of propeller wash, but unless moved or modified, the four CSOs discharging into this area could
affect the cap integrity. Failure of either the cap or the bulkhead would allow release of the
dredged materials back into the harbor system. At a minimum, a turbidity plume would likely
be evident
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Environmental Consequences: Shoreline Sites
Indirect Impacts - Downstream Resources
Anadromous fish spawning runs in the Mystic River would be the downstream
biological resource of greatest concern for Amstar, Revere Sugar, Mystic Piers and Little Mystic
Channel. The Chelsea River supports winter flounder spawning and has several small intertidal
flats that would be of concern with use of the Cabot Paint site. Barring catastrophic failure of the
containment structure, the likelihood of impacting these resources would be limited.
Similarly, harbor water users (e.g., lobster pounds and the New England Aquarium)
would be unlikely affected by the use of these sites.
Located near the mouth of the Inner Harbor, at the head of the navigational channel,
the Reserved Channel site is closer to the biological resources of the Outer Harbor than the other
shoreline sites. However, except in the event of cap or bulkhead failure, it is unlikely to influence
these resources. Discharge of silt from the Reserved Channel containment area could affect the
intake at Boston Edison; this would be likely only in the case of failure of the cap or bulkhead.
Indirect Impacts - Biological Exposure Potential
Filling of any of the shoreline sites would be conducted in complete isolation from
the waters of Boston Harbor. No pelagic or benthic organisms would be exposed to the BHNIP
silt after it had been disposed in one of the shoreline containment sites. In the partial fill
scenarios, the final cap would be of sufficient thickness to ensure that it would not be breached
either through bioturbation or physical forces. In the fastland scenarios, the site would remain
isolated from Boston Harbor waters and their associated biota for perpetuity. However, if the
fastland areas were left uncovered, with a lens of water on the surface, it is likely that they would
be attractive to diving birds. This could pose some risk of exposure to contaminants. Although
there would be little or nothing upon which to feed, birds that attempted to forage could ingest
some sediments. Others could be exposed though skin contact with the water, although this is
unlikely. Although individual birds would be unlikely to attempt to feed in the containment area
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Environmental Consequences: Shoreline Sites
for'extended periods because of limited success, such an area could be attractive to birds for
resting.
Other Issues
No federally or state-listed threatened or endangered species are identified or expected
to occur within the vicinity of the Mystic Piers, Revere Sugar, Amstar, Cabot Paint, Little Mystic
Channel or Reserved Channel sites.
The proposed project at the Mystic Piers, Revere Sugar, Amstar, Cabot Paint, Little
Mystic Channel or Reserved Channel would have no effect upon any structure or site of historic,
architectural or archeological significance as defined by MHC or the National Historic
Preservation Act of 1966, as amended.
The disposal operations at most of the shoreline sites (Mystic Piers, Revere Sugar,
Amstar and Cabot Paint) could be handled by barge transport, avoiding impact to traffic on public
streets. Because of restricted passage under bridges, disposal activities at Little Mystic Channel
and Reserved Channel would require transfer of material from barges to trucks and transport on
public streets. Selection of Amstar for disposal of BHNIP materials would displace the MWRA
water transportation facility and potentially displace a sand and gravel operation on the site. Use
of the Cabot Paint site would tend to aggravate the existing concerns about navigation in that
portion of the Chelsea River. Disposal of dredged materials in the upper Reserved Channel would
require the relocation of existing CSOs and could interfere with an existing yacht club. There are
no current uses of the Mystic Piers, Revere Sugar or Little Mystic Channel sites that would be
affected by use of these sites for dredged material disposal.
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In-Channel Areas
2.4 SITE EVALUATIONS; IN-CHANNEL
AREAS AND BORROW PITS
2.4.1
Existing Conditions
2.4.1.1 In-Channel Areas
The In-Channel disposal scenario is simply the placement and capping of dredged
material within the channel/tributary from which it had been dredged.
Silt and sediments would be dredged from each channel, placed on a barge, a deeper
trench would then be dug in the channel, and the silt and sediment placed within the trench and
capped. The proposed use and methods are described in more detail in Section 3.0 of the EIR/S.
Each channel/tributary would contain its own silt material and be capped therein. As the
environmental resources and consequences for this disposal alternative are the same as for the
dredging site, the existing conditions of the water and sediment quality., biological and socio-
economic environment in each site are described in the Section 3.0 of the EIR/S.
2.4.1.2
Spectacle Island Confined Aquatic Disposal (CAD)
The site is depicted on Figure Al-15.
SEDIMENT CHARACTERISTICS
The CA/T project examined sediments in and near this area with ponar grabs and
borings to characterize the surficial material and underlying sediments (Cortell 1990b) (Table Al-
9). Surface sediments tended to form broad areas of uniform grain size. Fine sand (with some
silt) predominated in a 500-foot band following the northeastern shoreline to about mid-island,
300 feet beyond MLW and recurred beyond the mussel bed several hundred feet further south.
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In-Channel Areas
From mid-island and beyond the southern sand band, sediments were primarily silty, with some
clay. Seaward of these areas, surface sediments were clay with some silt (Cortell 1990b).
Bulk sediment analysis of borings indicated that surface and near surface sediments
offshore of the eastern shoreline of Spectacle Island were generally free of contaminants (Cortell
1990b). Three of the five borings (ST1-7, ST1-9, ST1-11; Table Al-9) in the area proposed were
classified as Category I under the Massachusetts criteria for the classification of dredged materials,
although volatile solids at ST1-11 were within the Category n range (7-9 ppm) (Table Al-9).
Elevated levels of arsenic, a naturally occurring metal in New England soils, caused surface
sediments at ST1-8 and ST1-12 to be classified as Category II (12-20 ppm); subsurface
concentrations of arsenic resulted in Category HI (>20 ppm) classification of sediments below one
foot at ST1-8 (Appendix C-l; Table 2 of the Sampling Plan). Because of these findings, the
proposed disposal location has been designed to involve only those areas where Category I
sediments were recorded (see Figure Al-15).
WATER QUALITY AND CIRCULATION
The hydrodynamics around Spectacle Island were examined for the CA/T (Cortell
1990b). Circulation is dominated by tidal currents, affected by the distribution of islands and
channels in the Outer Harbor. Ebb tide currents passing the east side of Spectacle Island can
reach 0.6 knots on spring tides, while spring flood tides reach 0.4 knots. The broad shallow
subtidal area off the eastern shore diverts currents toward the channels (President Roads to the
north; Sculpin Ledge to the southeast). The area proposed for the CAD is subjected to lower tidal
currents created by eddies. Waves in the vicinity of Spectacle Island are primarily storm driven.
The maximum fetch for Spectacle Island is 7.1± nautical miles. Wave energy for the area was
calculated for the Massport Logan Inclined Safety Area (ISA) EIR for storms with wind velocities
from 10 to 50 knots. The wave breaker height near Spectacle Island ranged from 0.09 to 2.60
feet with wave powers of 0.1 to 412.9 ft-lb/sec.
The waters in the vicinity of Spectacle Island have been classified as Class SB waters.
This classification protects saline waters for the propagation of marine life, primary and secondary
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In-Channel Areas
contact recreation and shellfish harvesting with depuration. Water quality in the Outer Harbor
area historically has been influenced by raw sewage discharges, CSOs, various industrial
discharges, urban runoff and the pollutants flowing from the Inner Harbor system. However, as
upgrades to treatment processes are completed, water quality in the Harbor has, and will continue
to improve.
AQUATIC RESOURCES
Benthic Infauna
Benthic resources east of Spectacle Island were examined for the CA/T project
(Stations 6, 7, 9, 10; Cortell 1990b). Comparison of stations (through cluster analysis) indicates
that these stations were similar in terms of species istructure (Battelle 1988). The faunal communi-
ty was dominated by the tube dwelling amphipod Ampelisca dbdita (37%) and the gastropod
Nassarius trivittatus (20%), reflecting relatively clean, sandy sediments. Nephryid polychaetes
(Nephtys caeca and N. ciliatd) were also numerically important at these stations. Total abundance
(ranging from 653-3107/m2) was low compared to other sandy areas (Massachusetts Bay) and silty
areas of the Inner Harbor (up to 241,230/m2). Station 10, off the northeast shoreline of Spectacle
Island, had the highest abundance and number of taxa of the 11 stations sampled around the
island. Larger fauna were evaluated qualitatively along transects swum for lobster investigations
(Transects 3 and 4 reached the shoreward portions of the proposed CAD site; Cortell 1990b). In
addition to Nassaritts sp. and Ampelisca sp. the offshore portions of these transects supported
nereid worms (sand worms), Pagums sp. (hermit crabs), Panopeus sp. (mud crabs) and Cancer
irroratus (rock crabs).
Sediment profile camera sampling on the east side of Spectacle Island in the area
proposed for disposal revealed a well-developed benthic community intermediate between a
pioneering or colonizing and equilibrium stage (NAI and Diaz 1995). The majority of the stations
had silt sediments. The depth of the RPD layer ranged from 1.5-5 cm, indicating sediments were
well oxygenated. The sediment surface was overlain with mats composed of Ampelisca amphipod
tubes in varying stages of succession. Benthic samples showed that Ampelisca sp. was the
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In-Channel Areas
dominant taxon, composing 56% of the total abundance. (Habitat I, Table Al-10). Secondary
dominants included Aricidea (Acmira) catherinae (15%) and Polydora cornuta (7%). Total
abundance, 64,870.6/m2, representing 59 taxa, was intermediate among the Outer Harbor locations
that were sampled, but at least an order of magnitude higher than that observed previously (Cortell
1990b). Slightly more than one third of the stations had silt sediments with a layer of fine sand;
shell hash and gravel were also observed on the sediment interface, (indicating an erosional
environment) along vntia.Ampelisca sp. tube mats. In these areas, the depth of the RPD layer was
closer to the surface (0.5-3.5 cm) than in other areas of Spectacle Island. Evidence of
bioturbation was observed in all areas, including infaunal worms, burrows, and oxic and anoxic
voids. Benthic samples revealed that Ampelisca sp. was the dominant taxon, composing 60% of
the total abundance (Habitat H, Table Al-10). Total abundance, 102,025/m2, representing 41 taxa,
was nearly double the total abundance in other areas of Spectacle Island. Secondary dominants
were similar to other areas of Spectacle Island with one exception. The opportunistic polychaete
Polydora cornuta (22% of the total abundance) was joined by Streblospio benedicti (18%) and
Aricidea catherinae (5%). Nephtyid polychaetes, an important food for lobster and demersal fish
such as winter flounder, were collected in moderate numbers.
Lobster
A lobster transect survey was undertaken to quantify lobster use of the area and
evaluate the substrate for use or potential use by early benthic phase lobsters, considered to be a
vulnerable stage for this species because of limited habitat availability (Wahle and Steneck 1991).
CA/T transects 1 (southernmost), 2, 3, 4 and 5 (northernmost) were located along the east side
of Spectacle Island (Cortell 1990b); transects 3 and 4 were within the area proposed for the CAD.
Free-living lobsters were most abundant off the north shore of Spectacle Island (Transect 5
yielded 0.0027/fl:2; Transect 6 yielded 0.0035/fi2); Transect 3 yielded the third highest abundance
(0.0022/ft2). Abundances along Transects 1,2 and 4 were low (0.0003-0.0004/ft2). These average
abundances, however, do not account for the fact that lobsters were concentrated towards the
deeper end of all transects except Transect 3. Lobster pot markers were present in the proposed
site during all three surveys in 1990. Pot markers tended to be most heavily concentrated off the
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In-Channel Areas
northern shoreline of the island and farther east of the island in Sculpin Ledge Channel (Cortell
1990a).
During a lobster monitoring program run from early May to early July, 1992 in the
Harbor, Cortell (1992) reported that an average of five lobsters (average catch per 3-day haul, all
size classes) per trap were collected at a station just to the north of Spectacle Island, the southern
side of the ship channel. This catch was typical of several other stations in this study. Other
trawl sampling indicated that abundances were generally lower at a site (closest to Spectacle
Island) just north of the Ship Channel in President Roads, compared with four other stations in
the channel area. At the time, lobstermen fished this area along the edge of the channel between
Spectacle and Long Island.
No early benthic phase (EBP) lobsters were found in samples collected along lobster
transects. The preferred cobble substrate (Wahle and Steneck 1991) was common only along the
nearshore portions of Transects 1 and 5. Mussel beds may also enhance substrate suitability
(Wahle and Steneck 1991). Mussel beds occurred along the nearshore portions of Transects 2,
4 and 5. It was speculated that the anoxic sediments underlying these mussels would preclude use
by EBP lobsters (Cortell 1990b). The borings collected offshore of these transects indicated that
sediments were fine-grained, unsuitable for EBP lobsters (Cortell 1990b).
A lobster survey in October 1994 collected a total 0.2 lobsters per trap-day, all under
the legal size limit (Table Al-7). The CPUE at this site was among the lowest of the stations
sampled in Boston Harbor. No commercial lobster pots were observed in the area during the
survey. Conversations with local lobstermen at the time of the survey indicated that they no
longer fish in the area because of a lack of lobsters (NAI 1995b). Trawl sampling in October
1994 captured an average of 6.7 lobsters (based on 5 minute tow results standardized to a 20
minute tow), which was similar to that collected in the Chelsea River and Subaqueous E, and an
order of magnitude lower than the lobster catch at Boston Lightship (Table A1-4).
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In-Channel Areas
Finfish
A trawl survey of demersal fish in October 1994 collected a average of 21.3 finfish
per 20 minute trawl, one of the lowest catches in the Boston Harbor area (Table Al-4). Winter
flounder was the predominant species (9.3 CPUE), followed by skate' sp., both of which are
typically demersal. Rainbow smelt and Atlantic silverside, generally pelagic species, were also
collected.
Based on the on-going development of the artificial reef design, as required by the
Individual Permit—Landfill Closure and Maintenance at Spectacle Island for CA/T (ACOE no.
199202207; 2/16/93), target fish species in the Spectacle Island area include forage species such
as Atlantic menhaden, Atlantic herring and rainbow smelt, and predator species such as winter
flounder, striped bass, bluefish, pollock, Atlantic cod, tautog and cunrier. The northeastern half
of Sculpin Ledge Channel is the recommended location for the proposed terrace reef (NAI 1993).
WETLAND RESOURCES
I
The Spectacle Island CAD location is considered Land Under the Ocean under the
Massachusetts Wetland Protection Act (310 CMR 10.00) and Tidal Waters under the Federal
Clean Water Act (40 CFR 230). As Land Under the Ocean, the site is considered to be significant
to the protection of marine fisheries, protection of land containing shellfish, storm damage
prevention, flood control and protection of wildlife habitat. This area has been demonstrated to
provide habitat for free-living, but not early benthic phase, lobsters and juvenile rock crabs
(Cortell 1990b). Active use of the area by finfish has not been examined but is likely to occur
to some degree for feeding (although benthic fauna is sparse) and passage. Waterfowl may feed
in this area. Portions of the nearshore area of Spectacle Island are classified as Land Containing
Shellfish (mussels). The proposed subtidal location of Spectacle Island CAD intercepts the tidal
currents from the channels, reducing their intensity. This increases deposition offshore from the
shellfish beds, protecting them from excess siltation. Shoreline erosion is reduced by the
reduction in currents. Storm energy is dissipated by the shallow subtidal expanse east of the
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In-Channel Areas
island. Because this is an open water area, however, the shore east of Spectacle Island provides
little flood control.
Classified as Tidal Waters under federal regulations, Spectacle Island CAD was
evaluated for its ability to provide the functions of sediment/toxicant retention, nutrient
retention/transformation, recreation and uniqueness/heritage. Sediment sampling at this site
revealed only low levels of chemicals and low-to-moderate levels of fine-grained sediments.
However, reduced currents provide Spectacle Island CAD with greater potential for performing
the functions of sediment/toxicant retention and nutrient retention/transformation than the adjacent
channel areas. It is likely that recreational boaters with shallow-draft vessels cross this area.
Human use of the island will increase once park development is underway.
WILDLIFE
Waterfowl, including great cormorant (Phalacrocorax carbo), herring gull (Lams
argentatus), white winged scoter (Melanitta deglandi), common goldeneye (Bucephala clangidd),
bufflehead (Bucephala albeola), mallard (Anas platyrhynchos), black duck (Anas rubripes),
merganser (Mergus spp.) and scaup (Aythya spp.) have been observed in the vicinity of Spectacle
Island (Cortell 1990a). Each of these species feed on fish and invertebrates (Martin et al. 1951;
Whitlatch 1982; DeGraaf and Rudis 1986) that occur in the area proposed for Spectacle Island
CAD.
THREATENED AND ENDANGERED SPECIES
No federally or state-listed threatened or endangered species are identified or expected
to occur within the immediate vicinity of Spectacle Island CAD. Common terns have nested on
a dilapidated pier on the northwestern end of Long Island, approximately 0.6 miles away, across
Sculpin Ledge Channel. All marine mammals are protected under the Federal Marine Mammals
Protection Act. Harbor seals (Phoca vitulina), harbor porpoises (Phocena phocena) and
grampuses (Grampus griseus) occur occasionally in the harbor. None of these species are listed
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In-Channel Areas
as threatened or endangered. There are no natural occurrences of exposed ledge that would be
suitable as seal haul-outs in the vicinity of Spectacle Island CAD.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources at the Spectacle Island CAD
site.
SOaO-ECONOMIC/LAND USE
Activities at the subtidal area east of Spectacle Island would be visible from Spectacle
Island, Long Island, and Deer Island as well as from vessels using Sculpin Ledge Channel and
President Roads. Currently public access to Spectacle Island and Long Island is limited although
park development on Spectacle Island is expected to begin in 1995. Vessels using President
Roads are predominated by commercial ships, whereas Sculpin Ledge Channel is actively used
by fishing vessels and pleasure boats.
_
This location is currently used only by fishermen and recreational boaters. The site
is less than 1000 ft. from the proposed dike which the Massachusetts Highway Department intends
to construct as part of its closure of the abandoned landfill at Spectacle Island.
2.4.13 Meisburger Sites 2 and 7
These sites are depicted on Figures Al-16 and Al-17.
Al-106
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Meisburger Sites 2 and 7
SEDIMENT CHARACTERISTICS
The sand and gravel deposits that characterize these sites were first described by
Meisburger (1976) from sub-bottom data. The sites are in approximately 100 ft of water (80-110
range). Sand and gravel form much of these irregularly shaped deposits and a layer of medium
sand (up to three feet thick) may cover some of these areas locally. Because these sites are within
the nearfield study area of the proposed MWRA outfall, they have received recent detailed
inspection (Shea et al. 1991, Butman et al. 1992 and Blake et al. 1993). A.4 x 5 nautical mile
area around the proposed outfall was characterized in detail by Butman et al., (1992) and the most
common sediment type in the area surveyed was coarse sand and gravel (42%). These deposits
lay between gravel and boulder covered drumlins which comprised 23% of the study area. Fine-
grain sediments (6%) and a highly variable or patchy distribution of mud, sand and gravel (29%)
made up the remainder of the cover. The areas described by Meisburger (1976) are predominately
covered with sand and gravel although the boulder areas border some of the deposits in these
areas. Results of other studies in this area (Blake et al. 1993; Shea et al. 1991) are generally
consistent with the above findings although most of their data were collected from REMOTS
unages from representative data. Studies from this area point out that bottom sediments indicate
higher energy areas in some locations while other areas appear to be depositional (silt, clay
sediments), with sand underneath.
WATER QUALITY AND CIRCULATION
Again, because of the proximity of these site locations relative to the MWRA offshore
outfall site, recent studies have focussed on this area and long-term monitoring of water quality
and hydrography is planned (MWRA 1991). Although a 3-D hydrodynamic model of Massachu-
setts/Cape Cod Bays is still in development, intensive physical oceanographic surveys were
conducted between April 1990 and June 1991 (Butman et al. 1992). Some of this long-term
monitoring is located immediately adjacent to the MWRA outfall at Buoy "B". While the report
should be referenced for the details of initial findings, some relevant findings to this assessment
include:
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Meisburger Sites 2 and 7
> There is an absence of well-defined current in this area, but water and particle
transport takes place by a variety of actions, including tides, winds and river
flow;
+ Maximum tidal currents 1.0 m off bottom are hi the range of 6-8 cm/s in this
i
area (the mean is in the 2-4 cm/s range), compared with much faster currents
(18-20+ cm/s) at the mouth of Boston Harbor and somewhat slower currents
(4-6 cm/s) at the MBDS. Mean water currents at 5.0 m at this site are
typically in the 4-7 cm/s range;
»• Maximum re-suspension of fine-grain materials coincides with storm events
that show a 2-4 fold increase in suspended material in the water column
compared to background (i.e. non-storm periods) in the whiter.
The waters in this area have been classified as Class SA. This classification protects
the saline waters for the propagation of marine life, primary and secondary contact recreation and
shellfish harvesting without depuration hi approved areas.
AQUATIC RESOURCES
Benthic Infauna
Recent studies (Blake et al. 1993) have involved benthic sampling adjacent to
Meisburger 2 in areas shown by Butman et al. (1992) to have a patchy distribution of mud, sand
and gravel or a mud or fine sand cover. The station nearest Meisburger 2 in Blake's study had
63% sand and gravel. Infaunal benthic densities averaged 83,325 per m2 with the number of
species totalling 67 (samples were collected through a 0.3 mm sieve). The community was
composed mainly of a polychaete assemblage dominated by Spio limicola, Polydora socialis, and
Mediomastus californiensis.
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Meisburger Sites 2 and 7
Sediment profile camera sampling at both Meisburger 2 and Meisburger 7 in 1994
indicated several benthic communities were present. Approximately half of the stations at each
site contained primarily rock sediments intermixed with sand and gravel, indicating a high-energy,
erosional bottom habitat (NAI and Diaz 1995). Epifauna were observed colonizing the rocky
substrate. No RPD layer was observed because sampling gear was not able to penetrate the
substrate. Benthic fauna in this habitat (V) at Meisburger 2 had moderately high abundance
(11,075/m2) representing 55 taxa from one 0.04/m2 sample (Habitat V, Table Al-11). The most
abundant species was the tube-dwelling amphipod Unciola inermis (11% of the total abundance),
followed by spionid polychaetes Polydora quadrilobata (11%), and Prionospio steenstrupi (Table
Al-11). This community at Meisburger 7 had one of the lower abundances at offshore stations
(4962.5/m2), representing 61 taxa from 2 0.04-m2 samples (Habitat V, Table Al-10). Polychaetes
were the most numerous organisms. Dominants included the surface dwelling spionid Polydora
socialis, deep dwelling maldanid Euclymene collaris, and lumbrinerid Ninoe nigripes. The
presence of deep dwelling organisms is an indication of a healthy benthic community.
Approximately one third of the remaining areas at Meisburger 2 had sand substrate,
in some cases with overlying silt (NAI and Diaz 1995). The RPD layer, when observed, ranged
from 1.2-2.0 cm, indicating sediments were relatively well oxygenated. A moderate number of
fauna tubes were observed at the sediment surface and on rocks. Infaunal burrows were observed
in the cases where subsurface observations were possible. Benthic samples revealed a diverse
community (150 taxa in the 6 0.04-m2 samples) with moderately high abundance (9,534/m2,
Habitat VTf, Table Al-11). Polychaetes predominated, including spionid Polydora quadrilobata
(10% of the total abundance), and Polydora socialis (9%) and cirratulid Aphelochaeta marioni
(9%). Many surface-dwelling crustaceans, including cumaceans, isopods, and amphipods,
occurred hi low numbers. Epifauna (taxa such as Hydrozoa, Bryozoa, and Ascidacea) were
present. The remaining stations at Meisburger 2 had heterogenous sediments, mainly sand and
gravel with some silt and rock. The depth to the RPD layer, when observable, ranged from 0.5-
1.5 cm below the sediment surface. The total number of individuals, 17,925/m2, was the highest
of the offshore stations that were sampled (Habitat Vm, Table Al-11). Polychaetes such as
spionid Polydora quadrilobata (23% of the total abundance), ssHoe\\idEuchoneelegans(l4%), and
cirratulid Aphelochaeta marioni (11%), were the most abundant organisms. A total of 88 taxa
were collected in the 2 0.04-m2 samples.
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Meisburger Sites 2 and 7
Most of the remaining stations at Meisburger 7 had a gravel substrate mixed with sand
and/or rocks (NAI and Diaz 1995). The RPD layer, when observed, was within 1 cm of the
sediment surface, with one exception (8.0 cm, station 23). Epifauna tubes were observed on the
sediment surface. Observations of the subsurface area in many cases could not be made because
the substrate was impenetrable. Silt sediments, in some cases with a layer of fine sand, were
observed in a small area on the western edge of Meisburger 7. This area had evidence of well
oxygenated sediments, as indicated by an RPD layer generally at a depth of at least 5 cm. There
was evidence of bioturbation including oxic voids and burrows.
Lobster
A lobster survey using experimental traps was conducted in October 1994.
Meisburger 2 had the highest CPUE of all stations visited in Boston Harbor, a total of 6.4 per trip-
day, of which 0.1 met the legal size limit (Table Al-7). Meisburger 7 had second highest lobster
catch of all sites, 5.1 per trip-day, of which 0.1 were of legal size. Lobsters were also collected
in gill nets set at the Meisburger sites in October 1994 (Table Al-6). An average of 5 lobsters
per 24 hour set was collected at Meisburger 2, and 4.3 lobsters at Meisburger 7. Lobsters were
rarely collected in gill net collections at other sites in Boston Harbor. A review of the
Massachusetts Division of Marine Fisheries data on the location of the lobster fishery fishing
effort in 1991, 1992 and 1993 showed fishing traps in the vicinity of Meisburger 7, but no traps
located near Meisburger 2 (NAI 1995b).
From a commercial fisheries perspective, these sites are within the area of greatest
territorial harvest for the coastal lobster fishery (unpublished data, MADMF 1991). For example,
Area #4 (which extends from Lynn to Cohasset) accounted for 41.1% of the 11,000,500 pounds
caught (on coastal licenses) in Massachusetts territorial waters. Site-specific catch data for these
disposal sites were not available.
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Meisburger Sites 2 and 7
Trawl data provided by the MADMF (1991-92 Resource Assessment/Surveys,
unpublished data) for a station two nautical miles west of the new MWRA outfall indicated that
three commercial finfish species (winter flounder, Atlantic cod and yellowtail) made up 40-60%
(collectively) of the total catch (Table Al-12). The total catch (all fish) from two spring (May
'91 and '92) collections were 655 (20 min. tow) and 685 (13 min. tow); a total of 17 and 60
lobsters were also collected from these same tows. Rock and Jonah crabs were found in small
numbers. Total abundances of fish and lobster at this site were average to above average
compared with 10 sampling events (in May and August 1991-92) distributed offshore from
Nantasket Beach to the MBDS.
A gill net survey at Meisburger Sites 2 and 7 was conducted in October 1994. Gill
net CPUE (fish only, per 24-hour set) averaged 12.3 at Meisburger 2 and 17.4 at Meisburger 7,
moderate among the Boston Harbor stations where samples were collected (Table A1-6).
Mackerel was the most abundant species collected. Longhom sculpin, cunner, and Atlantic cod,
all typically demersal species, were secondary dominants.
WETLAND RESOURCES
The Meisburger sites exist beyond the geographical and depth jurisdiction of the
Massachusetts Wetlands Protection Act and Regulations (MGL c.131, s.40, and 310 CMR 10.00).
These sites fall within the federal designation of tidal waters since they fall within the territorial
sea of Boston Harbor, and the associated 3 mile limit of jurisdiction required for the discharge of
dredged or fill material under Section 404 of the Clean Water Act.
WILDLIFE
Approximately 35 species of marine mammals, 5 species of marine turtles and 40
species of seabirds occur within the Gulf of Maine. Aerial surveys were conducted for the ACOE
Al-111
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Meisburger Sites 2 and 7
to assess the use of the Massachusetts Bay Disposal Site (MBDS) by marine mammals, reptiles
and seabirds (MBO 1987). The dominant species observed within the MBDS locale are typical
of the offshore waters of Massachusetts (Meisburger and Boston Lightship sites).
Seabirds observed include northern fulmar (Fulmanus glacialis), shearwater (Puffinus
sp.), storm petrels (Hydrobatrae), northern gaument (Sila bacscms), Pomarine jaeger (Steriovarius
pomarinwri), gulls (Larinae) and Alcids (Alcidae). Dominant nonendangered mammals include
minke whale (Belasnoptera acutorostrata), white-sided dolphin (Lagenorhynchus acutus), and
harbor porpoise (Phocena phocend). Although five species of turtles potentially could occur on
Massachusetts Bay, only the leatherback turtle (Dermochelys coriacea) is typical in the area.
THREATENED AND ENDANGERED SPECIES
The following threatened and endangered aquatic species can occur in the Western
North Atlantic including parts of Massachusetts Bay (U.S. Department of the Interior 1991):
Cetaceans
right whale (Eubalaena gracilis) (Endangered)
humpback whale (Megaptera novaeangliae) (Endangered)
finback whale (Balaenoptera physalus) (Endangered)
sei whale (B. borealis) (Endangered)
sperm whale (Physeter macrocephalus) (Endangered)
blue whale (B. musculus) (Endangered)
Kemp's ridley (Lepidochelys kempi) (Endangered)
leatherback (Dermochaelys coreacea) (Endangered)
hawksbill (Eretmochelys imbricatd) (Endangered)
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Meisburger Sites 2 and 7
loggerhead (Caretta corettd) (Threatened)
green (Chelonia mydas) (Threatened)
Fish
shortnose sturgeon (Acipenser brevirostrum) (Endangered)
Studies have shown that the majority of local threatened and endangered whale
sightings have been concentrated near the tip of Cape Cod in the northern and central areas of the
Great South channel and north of Cape Cod along Stellwagen Bank and Jeffrey's Ledge (ADL
1992). The sightings offshore from Boston Harbor are typically concentrated eastward of the
MBDS, within the newly designated Stellwagen Bank National Marine Sanctuary. The
Meisburger sites are approximately half way between Boston Harbor and the MBDS and are not
a reported area of concentration for these species. Whale watch cruises out of Boston Harbor do
not attend these areas.
Of the five threatened or endangered turtles that could occur hi this area, the
leatherback, Kemp's ridley and the Loggerhead are the most regularly observed in Massachusetts
and Cape Cod Bays. Of these species, the leatherback is the most frequently encountered, with
the western North Atlantic estimated to support 16,000 individuals (Lazell 1980); however, it is
primarily an oceanic species. The loggerhead may show the most common inshore occurrence.,
with 7,700 individuals estimated to be in north and middle Atlantic coastal water (CETAP 1982).
The Kemp's ridley turtle would be the most rare, with the Atlantic population estimated to be less
than 500 individuals (Carr and Mortimer 1980). There is nothing unique about the Meisburger
2 and 7 sites that would attract these species nor are we aware of any specific sightings for this
area.
The shortnose sturgeon inhabits estuarine and freshwater areas along the eastern coast
of the U.S. and Canada and would not be an inhabitant of these open water alternative disposal
sites.
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Meisburger Sites 2 and 7
HISTORICAL AND ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources on the Meisburger 2 and 7
sites.
SOCIO-ECONOMIC/LAND USE
The Meisburger 2 and 7 sites are located in an area used for recreational boating and
for commercial fishing. The sites are easily reached by barge during fair weather conditions. The
sites are within one mile of the Massachusetts Water Resources Authority's Ocean Outfall,
currently scheduled for completion in 1995.
2.4.2 Environmental Consequences of the use of In-Channel and Borrow Pit Sites for
Dredged Material Disposal
In-Channel Sites
The areas of these channels that would be improved, as defined in Section 3.3, would
be overdredged (to -48 to -70 ft in the Mystic River and Inner Confluence and -49 to -65 ft in the
Chelsea River) to accommodate silt disposal. Disposal areas would be created in cells (Section
4.0), generally about 200 ft by 500 ft (2.3 acres) in size, for a total cell footprint of about 116
acres (Mystic River = 56 acres; Inner Confluence = 21 acres; Chelsea River = 40 acres). As cells
are filled, a sand and rock cap would be placed over the disposed dredged materials.
Direct Impacts
Because all disposal activities would be limited to the footprint of the improvement
dredging, there would be no additional direct habitat losses, either permanent or temporary, as a
result of the disposal. Closure of the disposal trenches would alter habitat conditions, however.
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Environmental Consequences: In-Channel Areas
A cap would be placed over the disposed silt to serve several purposes. Its primary
purpose would be to isolate the dredged silts from the harbor, isolating them from further biotic
activity or exposure. It has been demonstrated that a cap of 1.5 ft prevents the flux of
contaminants from sediments into the overlying water (Fredette et al. 1992). The proposed 3-foot
sand cap, armored where necessary with rock, would protect the silt from resuspension and
downstream transport caused by propeller wash of cargo ships and tugs passing through the
channels. The cap has been designed to be sufficient to prevent future maintenance operations
from disturbing it and releasing the covered silts; the rock on the surface provides a substrate that
would be easily identifiable by a dredge operator (either by "feel" or visually when the bucket was
opened into the barge) in the future.
The cap would temporarily be virtually free of chemical contaminants, an
improvement over the conditions currently present in the channels. Cap material would be highly
unlikely to adsorb contaminants - characteristically, mineral sediments do not. However, the cap
would probably not change the rate at which contaminated silt from other sources accumulated
in the channels. On average, the Chelsea Channel has been estimated to accumulate sediments
at a rate of about 1 inch per year. Sedimentation rates are much higher in the Mystic Channel;
they have been estimated to average 3 inches per year. It is unlikely that sedimentation is evenly
distributed throughout these channels, however.
Ships turning into the Mystic and Chelsea Channels from the Inner Confluence operate
at higher speeds than in the rest of the channel and thereby generate bottom currents that are
capable of resuspending silt on a regular basis. Therefore, this area may be kept swept clean of
silt for an extended period of time. Propeller wash generated by vessels and tugs passing through
the channels may be playing a major role in redistributing silts throughout the harbor. Bottom
currents caused by ships travelling even at low speeds resuspend a sediment layer up to 0.2 m
thick (OCC 1995). Most (95%) of this material is immediately redeposited, but about 5% is
available for transport. Localized short-term turbidity plumes are evident behind vessels traversing
the channels. The small-bodied, surface dwelling invertebrates that inhabit channel sediments are
probably also resuspended when this occurs. This action creates a continually disturbed benthic
environment in the channels. The cap material would not be resuspendable by these currents.
Therefore, the cap could reduce the rate of resuspension and resedimentation from propeller wash.
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Environmental Consequences: In-Channel Areas
Until the cap has been silted over, it could provide an improved habitat for survival
of winter flounder eggs (and other demersal species), both by providing a more stable structure
to which to attach and by creating an environment that is less stressed by siltation (resulting in
reduced "smothering")- Juvenile winter flounder would use the sandy areas because it provides
the granular sediments that this species burrows into. Flounder would not use the areas armored
by rock.
j
Benthic fauna capable of inhabiting the are armored by rock would likely differ from
the infauna present in the fine-grained sediments present now in the channels. The rock would
provide suitable substrate for attachment of fouling organisms, such as are now present on the
deeper portions of bulkheads and pilings around the harbor. These species could provide suitable
food for browsing fish and lobsters. Interstitial spaces in the rock would fill with sand or silt and
thus provide a more diverse habitat This would tend to increase the species diversity and enhance
the habitat
Indirect Impacts - Water Quality Effects
Modelling done to evaluate impacts to water quality during the disposal operations
(short-term impacts) is detailed in Appendix F. Conditions one hour after a single drop (after
steady state was reached) were used to predict the mixing zone. In the case of these in-channel
sites, the effects of nearby dredging were added to the disposal event. Conditions representing
repetitive disposal events were modelled to describe more typical conditions.
The distribution of suspended sediments and PCBs released into the water column was
modelled following an instantaneous release of silt from a barge in the Mystic River, the Inner
Confluence and the Chelsea River to determine appropriate mixing zones for each area.
Preliminary results indicated that disposal around high tide would prevent excessive buildup of
TSS or contaminants. Therefore, the mixing zone analysis assumed that this restriction would be
adhered to. In all three in-channel disposal locations, the mixing zone needed to meet the
proposed TSS limit (Appendix F) would be larger than that for PCBs, assuming that all Mystic
River sediments would be disposed hi the Mystic River channel. In each case, the mixing zone
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Environmental Consequences: In-Chanhel Areas
would be a narrow, elongated area running along the axis of the channel and would not extend
all the way across the width of the channel. The dimensions of the necessary mixing zones are
listed on Table Al-13.
Modelling of repetitive disposal events is more indicative of the level to which
constituents would accumulate in an area over the course of the project. It was predicted that
disposal would cause some buildup of suspended sediments (reaching equilibrium within a few
days) that would dissipate with distance from the disposal site, partially due to dilution with tidal
waters and partially due to the natural tendency for the particles to settle out of the water column.
Highest concentrations of suspended sediments (measured as total suspended solids or TSS) would
occur in the immediate vicinity of the disposal site (Table Al-14). Background concentrations
in the inner harbor were observed to be less than 5 mg/L prior to dredging the Third Harbor
Tunnel in 1992 (EA 1992). Dredging the Third Harbor Tunnel resulted in concentrations of total
suspended solids averaging about 21 mg/L 500 ft downstream of the dredge, with tidal stage
having little influence on the concentration.
Elutriate testing indicated that metals such as copper and mercury could dissociate
from the sediments and dissolve during disposal. Repeated discharges of dredged material would
have the effect of allowing these parameters to build up in the water column (reaching equilibrium
within about two months), particularly in the immediate vicinity of the disposal site. Dilution and
transport by tidal action would be the main factor causing dissipation of these parameters. Most
metals also have a high affinity for fine-grained sediments (e.g. silt); they would gradually be
reabsorbed to the particles and tend to drop out of the system with the silt. The highest
concentrations predicted for the dissolved metals (3.2 ng/L for mercury; 5.7 ng/L for copper,
Table Al-14) are well below the chronic water quality criteria (25 ng/L for mercury; 2900 ng/L
for copper) established by the USEPA (1986 UPDATE?).
Elutriate tests indicated that PCBs were likely to be released from sediments dropped
from the barge. Mechanisms similar to those described for the metals would control dispersion
of PCBs from the disposal site. Reparticularization is considered to be an important factor in
partitioning PCBs between dissolved and paniculate phases. PCB concentrations varied in the
Harbor; a portion of the sediments proposed for dredging from the Mystic River had substantially
Al-117
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Environmental Consequences: In-Channel Areas
higher bulk concentrations than the remaining sediments. Therefore, water quality models were
run using two different elutriate values. Even under worst case conditions (i.e., Mystic River
sediments), the PCB concentrations, including ambient, would be about 60% of the chronic water
quality standards.
Because of their high carcinogenicity, the potential for release of PAHs, represented
by naphthalene, was examined. Although PAHs were not measured in elutriate testing,
concentrations of the 16 individual priority pollutant PAHs were estimated based on organic-water
kinetics (see Appendix IV). Naphthalene was the most soluble of the 16 compounds in the
sediments. Applying these values to the water quality modelling, it was predicted that PAHs
would exhibit little accumulation in the water column. Naphthalene was predicted to occur at
concentrations nearly five orders of magnitude lower than the LOEL (lowest observed effects
level) water quality criterion of 2350 ppb (no chronic criterion has been established).
Indirect Impacts - Site Stability
Vessel traffic, particularly through the turns into the Mystic and Chelsea Rivers,
resuspends sediments in a triangular zone of influence reaching to 40 m wide 170 m astern of an
LNG tanker (the worst case). Vertically, the ship-induced velocities also dissipate with depth
below the center of the propeller. However, none of the cells are projected to be deeper than the
zone of influence. While the propeller wash would resuspend approximately a 0.2 m layer of
sediments in this area, about 95% of this material resettles rapidly. A ship traversing the 800 m
long turning area in the Inner Confluence would cause a net increase in suspended sediments of
about 423 cy. Other cargo vessels would have slightly less impact on the substrate, but would
also resuspend sediments. Ship traffic levels in Boston Harbor average about two cargo vessels
per day. The largest vessels, LNG tankers, enter the Mystic River at a rate of 1 to 2 per month.
This effect is of concern for the use of the in-channel disposal sites both during the
filling phase and following closure of the cells. During the filling phase (a period estimated to
last up to 14 days) the disposed sediments could be resuspended from within any cell within the
zone of influence of a passing vessel. The quantity of material resuspendable would increase as
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Environmental Consequences: In-Channel Areas
the cell was filled. While this effect would not differ from what normally occurs, it would be
counterproductive for the dredging and disposal operations. Ideally, this effect could be
minimized by careful scheduling of disposal to use the cells in the most vulnerable areas during
periods when LNG tankers are not scheduled, and to restrict vessels from passing within 20 m of
an open cell whenever safe navigational practices allow this.
Following closure of each cell, the cap could be susceptible to the erosional forces of
the vessel traffic as well. In this case, the concern would focus on maintaining the integrity of
the cap to prevent re-exposure of the disposed silts. Clearly it would be infeasible to restrict
vessel traffic. Therefore, the emphasis would have to be placed on the strengthening of the cap
itself. The ship simulation study (Appendix D in the DEIR/S) and geotechnical surveys in the
channels were examined to determine areas likely to be scoured on a regular basis. These were
identified as the areas most vulnerable to propeller wash effects. It is recommended that the caps
on the cells in these areas be armored with rock.
Long-term monitoring of dredged material capping in Long Island Sound (Fredette
et al. 1992) has indicated that no upward migration of contaminants through the cap would occur.
Fredette et al. found that after 11 years, the chemical signature of dredged silt and an
unengineered cap in Long Island Sound remained distinct. Migration of contaminants into the cap
was limited to about 10 cm. In this boundary layer, metals concentrations were < 5% of the
dredged material and selected PAH concentrations were 0 - 10% of underlying sediments. The
proposed rock layer on the surface of the cap at the in-channel disposal sites would armor and
prevent resuspension of the underlying sand by propeller wash. Initially, there would be no fine
sediments present on the surface, so turbidity caused by propeller wash could be reduced. It is
likely that silts will eventually be transported into the channels from other sources, however,
potentially negating this effect eventually.
Indirect Impacts - Downstream Resources
Downstream biological resources of concern include anadromous fish species (alewife,
blueback herring and rainbow smelt) on their spawning runs up the Mystic River, spawning winter
Al-119
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Environmental Consequences: In-Channel Areas
flounder (and their demersal eggs), and small intertidal flats (potential soft-shell clam habitat) in
the Chelsea River. Geographical areas of concern are shown on Figure A1-22.
Downstream areas are expected to experience minimal impacts for several reasons.
Dredging and disposal activities hi the Mystic River and the Inner Confluence will be avoided
during the period from February 15 to June 30 to prevent impacts to anadromous fish passage.
Restriction of activities during this time period would also help protect winter flounder spawning
areas. The primary concern for anadromous fish would be contact with elevated concentrations
of suspended sediments and exposure to elevated levels of dissolved contaminants. A plume of
elevated suspended sediments could deter the fish from entering the Mystic River prior to
spawning or juveniles swimming downstream in the late summer and fall if the plume spread
across the entire width of the channel, although Klauda et al. (1991) reported that the most
susceptible Kfestages (eggs and larvae) of alewife and blueback herring could survive exposure
to suspended solids in concentrations as high as 500 - 1000 mg/L. In this unlikely event, the fish
would probably congregate in a low current area until the changing tide reconfigured the plume,
allowing passage. Because the concentrations of dissolved constituents that are expected to occur
during the disposal would be below chronic water quality criteria, they would not impact
anadromous fish or other pelagic organisms.
Because winter flounder are demersal in all except larval lifestages, contact with the
substrate and exposure to increased sedimentation would be of greatest concern. Sedimentation
of material dispersed into the water column during each disposal event would likely be most
concentrated in an area about 240 ft (80m) north to 240 ft (80m) south of each cell for the period
that the cell was being filled (about one to two weeks per cell). Each disposal event could
contribute a layer of sediments about 1.4 cm (0.5 in) thick in this area, but build-up would be
unlikely because this layer would have a high water content and be easily resuspended and
transported. Mortality of winter flounder eggs subjected to sedimentation from this source would
likely increase slightly over existing conditions if ship passage does not resuspend this silt.
Because channel sediments represent the majority (78%) of the silt volume to be disposed, and,
except for the Reserved Channel, dredged material would be disposed in the tributary from which
it was dredged, this sedimentation would be unlikely to increase concentrations of contaminants.
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Environmental Consequences: In-Channel Areas
Intertidal flats along the Chelsea River would be unlikely to experience detectable
sedimentation. Sedimentation is most likely to occur parallel to the axis of the channel rather than
towards the shoreline.
There are a number of water intakes along the waterfront that are also of concern.
There are six lobster pounds and the New England Aquarium that draw water from the harbor to
support live animals. These intakes are generally located outside the zone of highest concentration
of TSS or contaminants anticipated for this disposal activity.
Indirect Impacts - Biological Exposure Potential
Water Column Exposure
None of the parameters that were suspected to be problematic in terms of water
quality (based on elutriate values or ambient conditions) are anticipated to concentrate to levels
exceeding the chronic water quality criteria. Highest concentrations would be restricted to a
limited portion of the harbor. It is assumed, therefore, that exposure of biota to these levels would
have no discernible effect. Water column exposure would be limited to the 1.5-year disposal
period.
Substrate Exposure
Because of the relatively small size of each cell (8,000 to 42,000 cy silt capacity),
dredged materials would be exposed only for a period of about 5 to 14 days, on average, prior
to capping. This would be insufficient time to allow recruitment of a substantial benthic
population and subsequent feeding by demersal fish. It is unlikely that finfish would linger in the
disposal cells because of elevated turbidity, general activity and lack of food resources. Even if
they did, exposure for one to two weeks would be unlikely to cause adverse effects for several
reasons. Bioaccumulation is typically assumed to require about one month of exposure to reach
equilibrium; most uptake would have to occur through dermal contact rather than ingestion. Each
cell has a footprint of 2.3 acres or less, less than 2% of the available substrate in the Mystic River
between the Tobin Bridge and the Amelia Earhart dam. And, finally, the chemical profile of the
disposed sediments would not be substantially different from the adjacent substrate.
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Environmental Consequences: In-Channel Areas
The small downstream areas subject to sedimentation may have a higher potential for
exposing substrate-oriented organisms to contaminants. Based on the relative volumes of dredged
material from the berths (22%) and the channels (78%), it is likely that downstream deposits
would reflect the chemistry of the channels rather than the berths. Because the only downstream
areas that are predicted to experience sedimentation because of disposal are in the channels, this
action is unlikely to increase exposure to organisms substantially over what they experience now.
Other Issues
No federally or state-listed threatened or endangered species have been identified to
occur in the channel and tributaries, so adverse impacts are not expected.
This disposal alternative would have no effect upon any structure of historic or
I
archeological significance as defined by MHC or the National Historic Preservation Act of 1966,
as amended.
BORROW PITS
There are three sites (Spectacle Island, Meisburger 2 and Meisburger 7) that could be
used as borrow pits - sites where existing sediments would be dredged and removed to prepare
the site for use. Of the three sites identified for this type of development, the two Meisburger
sites have deposits of sediments that would be suitable for beneficial uses (beach nourishment or
construction fill), while sediments at Spectacle Island would likely not. The Meisburger sites
could be developed either as cells or in one large compartment. It is unlikely that the existing
sediments near Spectacle Island would provide sufficient geotechnical strength to support
construction of small cells because borrow pit construction would not penetrate into parent
material at this site. The resulting cells or pit would be filled with silts from the BHNIP and
capped with sediments that had been reserved during the initial site preparation or pit creation.
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Spectacle Island CAD
SPECTACLE ISLAM) CAD
Spectacle Island CAD is located east of the island on a shallow tidal flat. Water
depths range from -8 to -12 ft MLW. Substrate is primarily fine sand and silt. Disposal of silts
from the BHNIP would require dredging one large containment cell over a footprint of 45 acres,
to a bottom depth of 23 ft below the existing substrate. Silt would be filled to a depth three feet
deeper than the surrounding substrate. Silt would be capped with sediment retained from pit
dredging to a final depth equivalent to adjacent substrate.
Direct Impacts
There would be no permanent loss or alteration of habitat associated with the use of
the Spectacle Island CAD. Dredging the cell would not impact areas outside the footprint,
although the material retained for the cap would likely be stored on substrate adjacent to the cell.
This would cause a loss of benthic productivity for the duration of the dredging project, about L5
years, in addition to the tune needed for the storage area to recover, probably an additional year
or more. Any remaining material dredged from the cell would be disposed at the MBDS. Benthic
fauna would be unable to colonize the cell for the duration of the disposal activities (about 1.5
years). Because the benthic community presently at the site (and throughout the outer harbor) is
dominated by the pioneering amphipod Ampelisca, it is likely that the cap would be at least
partially recolonized within a year of closure of each cell. Tube-building habits of this organism
plays a substantial role in stabilizing the sediments in the outer harbor.
If it becomes necessary to armor the self-cap with rock, the character of the benthic
community would change dramatically. Ampelisca does not occur on hard bottoms. It is possible
that the rock bottom, and interstitial areas where fine-grained sediments accumulated, could be
as productive as the Ampelisca community. Rock could support macroalgae and a diverse
macroinvertebrate community; interstitial areas could support many of the infaunal species
observed in the area in fall 1994. Such a substrate could complement the Central Artery's
artificial reef near the site in Sculpin Ledge Channel.
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Spectacle Island CAD
Indirect Impacts - Water Quality Effects
The mixing zone required for the disposal of BHNIP sediments at the Spectacle Island
CAD would be best defined by the area necessary to dilute total suspended solids to <50 mg/L.
Concentrations of TSS at this location would not be influenced by BHNIP dredging activities in
the harbor. Disposal at or around high tide would optimize the dissipation of vagrant sediments.
Under these conditions, the mixing zone would require an area of about 18.0 acres (240m by
270m) and would be oriented towards Sculpin Ledge Channel (Appendix IV).
Pollutant transport modelling indicated there was little potential for short-term water
quality impacts caused by the disposal of BHNIP silts in the Spectacle Island CAD (Table Al-15).
Indirect Impacts - Site Stability
Although its location is removed from the shipping channels where tidal currents peak
in the Outer Harbor, the subtidal fiat east of Spectacle Island could experience spring tidal flows
as high as 0.7 to 1.0 ft/sec (21-31 cm/sec). While these flows are high enough to resuspend
unconsolidated silts, existing Ampelisca beds probably stabilize these silts.
The shallow conditions east of Spectacle Island are generally avoided by most vessels
except small recreational boats. Therefore it is unlikely that this area would be exposed to
propeller wash that could resuspend sediments. The frequency of use by recreational boaters
would likely increase, however, after the artificial reef developed as mitigation for the Central
Artery project has been deployed. The anticipated date for this deployment is the summer of
1996, less than a year before dredging for the BHNIP is expected to begin.
The site for the Spectacle Island CAD is directly exposed to the Atlantic Ocean
through the mouth of Boston Harbor. The shallow conditions present at this site would induce
wave cresting and breaking. Wave-generated bottom-currents from a one-year storm could reach
5.8 ft/sec (>175 cm/sec), far in excess of the velocity needed to resuspend silt or sand. Therefore,
it is likely that this area would be subjected to erosion from storms or high winds each year.
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Spectacle Island CAD
Eventually the wave activity would tend to consolidate the surface sediments, as they are
presently. The location of this CAD away from the most exposed northern edge of this subtidal
flat would tend to help dissipate the effects of the waves. As with the other sites discussed,
armoring the surface with rock would prevent resuspension of the cap. However, this would
prevent recolonization of the cap with the Ampelisca-dominated benthic community that is
currently abundant in the area. It is unlikely that the Ampelisca could recolonize rapidly enough
to stabilize the cap before a one-year storm occurred.
Construction of a submerged breakwater northeast of the proposed CAD would help
reduce the impact of wave-induced bottom currents.
- Indirect Impacts - Downstream Resources
Resources of concern beyond the footprint of the proposed Spectacle Island CAD that
could be impacted include soft-shell clam beds, Ampelisca beds, winter flounder habitat
(coincident with Ampelisca beds), lobster habitat, the Central Artery artificial reef and the
swimming beach on the southern tip of Spectacle Island. Disposal activities could also present
a visual impact to Spectacle Island park users.
Although all the intertidal areas in the vicinity of Spectacle Island are considered to
be soft-shell clam beds, harvesting is prohibited on all potentially within the influence of the
Spectacle Island CAD. With the elimination of sewage sludge discharge at the end of 1991, and
the anticipated elimination of sewage effluent discharge in 1997, this status could change. The
eastern shoreline of Spectacle Island is being bermed to protect the island from storm erosion; this
area would no longer be able to support clams.
Most sediments dispersed from the disposal event would settle within about 80 m.
Site configuration indicates that sediments dispersed from disposal events taking place in the
central 18 acres of the CAD would settle primarily within the site boundaries. Vagrant silt from
disposal events located in the 27 acres along the perimeter of the site could settle in detectable
amounts in an area up to 80 m beyond the site boundaries, encompassing up to 38 acres. This
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Spectacle Island CAD
would form a transient layer about 0.34 cm thick after each disposal event. The high water
content in this layer would make it prone to resuspension, so accumulation of a thicker layer
would be unlikely.
The distal ends of the sediment plume could reach the intertidal areas of the
southeastern and southern sides of Spectacle Island and the northwestern side of Long Island, but
at concentrations <0.5 mg/L above ambient
Impacts to Ampelisca beds, winter flounder habitat and lobster habitat would be
similar to those described for Subaqueous B, but located in the vicinity of the east side of
Spectacle Island (Appendix F).
The proximity of the Spectacle Island CAD to the proposed artificial reef (in the
middle portion of Sculpin Ledge Channel) and swimming beach (on the southern tip of Spectacle
Island) being developed as part of the mitigation for the Central Artery/Third Harbor Tunnel
project is of concern. Dredging is expected to start in 1997, about one year after the deployment
of the artificial reef. Critical to the success of the artificial reef is its colonization by "fouling"
organisms such as mussels and algae. A prolonged period of increased turbidity caused by
elevated suspended sediments could affect the mortality rates of recently settled organisms. Water
quality modelling indicated that it is unlikely that the reef would be exposed to elevated
concentrations of suspended solids or dissolved contaminants.
I
The Central Artery project is closing the Spectacle Island landfill and creating a
harbor island park. It is expected to be open to the public in 2000. Part of the park design
includes a swimming beach at the sheltered southern tip of the island. The swimming beach could
be exposed to slightly elevated concentrations of suspended solids (<0.5 mg/L above ambient),
but it is unlikely that a plume would be visible. Most constituents modelled would have reached
ambient concentrations at this distance from disposal operations. The PAH naphthalene could be
i
present at levels from 1.0 to 2.0 ng/L above ambient in the vicinity of the beach. This is well
below concentrations of concern for human health.
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Spectacle Island CAD
Indirect Impacts - Biological Exposure Potential
Water Column Exposure
Like Subaqueous B and E, hydrodynamics at Spectacle Island CAD create a dispersive
environment. Water quality modelling predicted that there would be no excessive (i.e., above
chronic water quality criteria) buildup of dissolved contaminants. Therefore, it is unlikely that
pelagic organisms would be exposed to contaminant levels that would be deleterious to them
during disposal operations at Spectacle Island CAD.
Substrate Exposure
As at Subaqueous B, the routine disposal events would tend to preclude colonization
of BHNIP silts until the final cap has been put in place for each cell. The absence of food
resources and the frequent disturbances at the site would be likely to cause finfish and epibenthic
crustaceans from spending prolonged periods of time in a cell until the cell has been closed.
Therefore, it is unlikely that organisms would be exposed to the BHNIP silts and their associated
contaminants long enough to bioaccumulate contaminants.
Because the transport of resuspended sediments to downstream areas would be less
dramatic than the descent of dredged materials, organisms would not be likely to avoid these
areas. The sediment-bound contaminant loading described for Subaqueous B would also apply
to this site. It is unlikely that hydrodynamic conditions would allow the creation of identifiable
deposits of BHNIP silts released during disposal operations.
The temporary change in depth could increase the risk that finfish would enter the pit
during the summer months in search of cooler water temperatures and, consequently, be exposed
to contaminated sediments. However, monitoring for the Central Artery project and the fall 1994
sampling for the BHNIP suggest that the area around Spectacle Island supports a smaller finfish
population than other parts of the Outer Harbor and the Inner Harbor. If this is true, this potential
exposure route would present a minimal risk to finfish.
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Other Issues
The disposal operations would involve approximately 660 barge trips. This would
require Coast Guard coordination of barges with the commercial and recreational boat traffic using
the harbor. Construction activities would have a minor adverse aesthetic impact, and result in
slightly elevated noise levels.
If the filling is restricted to the depth of the surrounding area, there will be no
permanent impact on recreational boating. However, the placement of the material may
necessitate temporary restrictions on recreational boating. Because this is a shallow subtidal area,
dredging would be required. This will necessitate testing and a determination of the appropriate
disposal location for the sediments removed from this site.
l
The Massachusetts Highway Department (MHD) is currently constructing a dike
adjacent to this proposed disposal site for the purpose of containing and closing the landfill at
Spectacle Island. Lack of impacts from dredging the CAD on the integrity of the dike structure
will need to be demonstrated to the MHD as well as to the owners of Spectacle Island, the City
of Boston and the Massachusetts Department of Environmental Protection.
Part of the Spectacle Island Landfill Closure Plan also includes the installation of an
artificial reef hi the northeastern half of Sculpin Ledge Channel. Depending on the timing of the
Project, the fill placement at the Spectacle Island CAD location may need to be coordinated with
the construction and/or location of the fish reef to minimize interference and impacts. As
mentioned above, if the fish reef is in, place during the CAD construction/use, special mitigation
measures may be necessary to prevent silt plume exposure to this facility.
MEISBURGER2 AND MEISBURGER7
Meisburger 2 is located 2.3 miles southeast of Nahant; Meisburger 7 is located about
7 miles off Boston Harbor. Both occur in water depths of about 80 to 105 feet and were
identified as potentially minable sand and gravel deposits (Metcalf and Eddy 1992). Use of either
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Spectacle Island CAD
site for dredged material disposal would require dredging a series of pits, storing the surface
materials for future use in capping the BHNIP silts disposed there, and recovering the underlying
sand and gravel deposits for beneficial use. From an environmental standpoint, creation of small
cells for disposal is preferable to constructing one large pit. Small cells enable capping and
isolation of disposed silts more quickly. Subsequent recolonization of the cap can also occur more
quickly under this scenario. Because of the water depth, however, the site preparation would be
more efficient if surface material was sidecast onto adjacent substrate for storage and then scraped
back onto the cell. To minimize the extent of temporary impacts (i.e., smothering) to adjacent
substrate, it would be advantageous to dig cells in a planned geometric sequence, placing cap
material on top of the next cell to be excavated. This sequence would require that the hopper
dredge remain at the site throughout the entire period that disposal of BHNIP sediments occurred.
The specific locations of the sand deposits within the Meisburger 2 and 7 sites would
have to be identified prior to any final disposal plan. Because of expected variations in thickness
of these minable deposits, it is estimated that the disposal site would encompass an 86-acre area
(13 feet below existing substrate) at Meisburger 2 or a 121-acre area at Meisburger 7 (10 feet
below existing substrate). Creation of these cells would provide sufficient capacity for 1.3 million
cy of silt with a three-foot thick cap. Site bathymetry and surface substrate would be returned
to preexisting conditions.
Direct Impacts
Use of Meisburger 2 or Meisburger 7 would result in no permanent loss of aquatic
habitat. Benthic production would be temporarily halted during the use of each cell. The existing
benthic communities at both sites are a complex array of species and lifestyles (pioneering and
later successional stage species co-occur) that would probably take several years to reestablish.
Preexisting bathymetric and substrate conditions would be restored after each cell has
been filled. Therefore, use of the site would cause no permanent alteration of the habitat.
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Spectacle Island CAD
The Meisburger 2 and Meisburger 7 sites were both observed to support large lobster
fishing efforts in the fall of 1994. Use of either site would disrupt lobstering activities in the
footprint and immediately surrounding areas during disposal. Disposal would likely cause lobsters
to move out of the immediate area. Development of either site in cells would reduce the
likelihood that lobsters or groundfish would move into the pits and be smothered by disposed
dredged material. During construction activities, there would be disruption of fishing activities,
with an associated economic impact to the fishermen who utilize that area.
Indirect Impacts - Water Quality Effects
The mixing zone required for the high tide disposal of BHNIP sediments at either
Meisburger site to dilute total suspended solids to <50 mg/L would be an area of about 22.5 acres
(900m by 100m). Concentrations of TSS at these locations would not be influenced by BHNIP
dredging activities in the harbor.
Because of the large volume of water available for dilution, no short-term water
quality impacts were predicted with the ADDAMS model reported in the DEIR/S. Although
about 5% of the sediments from each barge load would be dispersed from either site, no water
quality exceedances beyond the disposal site boundary were predicted after four hours under
stratified conditions, consistent with Sec. 103 requirements.
Indirect Impacts - Site Stability
I
The relatively slow bottom currents at Meisburger 2 and 7 (maximum of 0.2 - 0.3
ft/sec [6-8 cm/sec]) are unlikely to resuspend silty sediments. Vessel traffic is primarily limited
to fishing boats whose relatively shallow draft and low powered engines (compared to cargo
vessels) are unlikely to affect the substrate.
However, no land masses protect either Meisburger 2 or 7 from the effects of high
winds and storms. A one-year storm could generate bottom currents of 3.2 ft/sec (98 cm/sec) at
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Spectacle Island CAD
Meisburger 2 or 3.6 ft/sec (110 cm/sec) at Meisburger 7. Unconsolidated sediments, such as the
silts proposed for disposal, could easily be resuspended under these conditions. Because of the
mechanical disruption from dredging, the sediments retained during construction of the borrow
pit to be used for the cap would be less compacted than in their original state and, therefore,
somewhat more susceptible to resuspension. However, the proposed three foot cap thickness is
expected to be sufficient to prevent future exposure of the buried dredged materials.
Indirect Impacts - Downstream Resources
Resources in the vicinity of the Meisburger 2 and 7 sites have been identified through
lobster trapping and gill net fishing; demersal fish have not been sampled there because of the
presence of fixed fishing gear. Important resources are likely to include lobster habitat, flounder
habitat, exploited fishing grounds and the MWRA sewage outfall. The downstream benthic
community is assumed to be similar to the conditions observed at Meisburger 2 and 7, that is,
diverse and productive.
Discernable downstream impacts would most likely be limited to the immediate
vicinity of the disposal site. Although suspended sediments would be transported away from the
site during each disposal event, concentrations would be low and settlement would be dependent
on prevailing currents at the time of the disposal. The area adjacent to the disposal activities
would have the highest likelihood of experiencing increased sedimentation. Depending on the
layout of the cells, some material would be likely to settle on other cells.
Lobster and bottom fish that were present at Meisburger 2 or 7 during disposal events
would likely move away from the area of increased turbidity. All told, the motile organisms
occupying the 86-acre footprint of the Meisburger 2 disposal site, or the 121-acre footprint of the
Meisburger 7 disposal site, would be displaced onto adjacent substrate. This could stress the
carrying capacity of the adjacent area, although the probability of this is unclear. Areas that also
experienced sedimentation would most likely be stressed; benthic standing crop could be
diminished.
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Spectacle Island CAD
About half of the area encompassed by Meisburger 2 was identified as having surface
substrate conditions that could be appropriate for Early Benthic Phase (EBP) lobsters. Nearly
90% of the substrate observed at Meisburger 7 was gravelly or pebbly in nature, potentially,
suitable for EBP lobsters. This lifestage has specific habitat requirements, particularly in terms
of shelter from predators, that may be the limiting factor in successful recruitment to harvestable
lobsters (Wahle and Steneck 1991). Although no EBP lobsters were observed at either Meisburger
2 or 7, this could have been an artifact of sampling design. While it is unlikely that sediments
dispersed from the disposal activities outside the disposal cell would blanket a given area thickly
enough to destroy the character of the substrate, the increase in the quantity of unconsolidated
fine-grained material could affect respiration of EBP lobsters by clogging their gills.
l
Depending on tidal and seasonal current patterns, effluent from the MWRA outfall and
materials dispersed from the disposal activities could interact. Water quality modelling for each
project predicts that farfield effects would be negligible. However, these models have yet to be
validated. The MWRA outfall is projected to go on line in 1997, the same year that dredging
would start in Boston Harbor. Interpretation of results of the stringent monitoring that will
accompany the startup of the MWRA discharge offshore would be severely complicated by the
presence of disposal activities hi such close proximity.
Indirect Impacts - Biological Exposure Potential
Water Column Effects
The rapid dilution of dissolved constituents and suspended sediments following each
disposal event would minimize the potential for pelagic organisms to be affected. No constituents
are expected to reach concentrations in the water column that exceed the chronic level water
quality criteria.
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Spectacle Island CAD
Substrate Effects
Existing sediments near Meisburger 2 (Transect D; MWRA 1988) contain PAHs at
concentrations ranging as high as the levels observed in Boston Harbor channels. The sediments
potentially proposed for disposal at Meisburger 2 probably contain substantially higher
concentrations of contaminants than currently exist there. Therefore, during the relatively brief
period that each cell would be uncapped, organisms that contacted the sediments could be affected
by the contaminants. However, as described for the In-Channel disposal scenario, there would
be several factors operating that would tend to reduce the likelihood of adverse impacts. It is
extremely unlikely that benthic organisms would colonize the exposed BHNIP silts because of
the relatively short period of exposure (because of construction in cells), the frequency of
disturbance, and the character of the local benthic community which consists mostly of later-
successional stage species (rather than pioneering species capable of rapid recruitment to disturbed
substrates). Absence of food and frequency of disturbance would tend to deter bottom-feeding
fish from lingering on the contaminated sediments.
Other Issues
The disposal operations would involve approximately 660 barge trips. This would
result a level of traffic that would need to be closely coordinated by the Coast Guard with
commercial and recreational boat traffic using the harbor. Construction activities would have a
minor adverse aesthetic impact.
The disposal operation at the site would prevent fishing and recreational boating for
the duration of the filling activity. A notice to fishermen warning them to avoid this area may
be necessary as may be a Coast Guard hazards to navigation notice (due to the regular presence
of barges). Although the project activity could provide a point of nuisance to fishermen for 1V2
to 2 years, adverse impacts to their fish catch are not anticipated given the relatively small area
affected compared to what is available for similar fishing ground. Long-term impacts to the
fishery are not expected because the dredge material would be isolated and not exposed to benthos
or fish. The proximity of the sites to the MWRA's ocean outfall assures some level of monitoring
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Spectacle Island CAD
(by MWRA) before and during placement of material; any construction impacts from the filling
operation could be evaluated from these data.
Use of these locations will entail dredging of existing sand and gravel prior to
placement of material. Some of the sand might be suitable for ACOE beach nourishment projects
provided it meets grain size, availability and suitability criteria for the specific beach nourishment
project. The ACOE is working with the MDC on beach nourishment projects in the Common-
wealth including Nantasket Beach, among others. "Piggybacking" projects in this manner is an
acceptable strategy to the ACOE. However, costs which must be factored into this option include
testing, processing and transporting the material, as well as alternate use or storage costs for that
portion of the material not appropriate for beach nourishment.
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Subaqueous Containment Site B (SUBAQ B)
2.5 SITE EVALUATIONS:
SUBAQUEOUS AREAS
2.5.1 Existing Conditions
The site is depicted on Figure Al-18.
2.5.1.1 Subaqueous Containment Site B (Subaq B)
SEDIMENT CHARACTERISTICS
Boring sites ST1-14 and ST1-15, sampled by the CA/T program (Cortell 1990a) and
presented in Table Al-16, were located off the northern side of Spectacle Island and represent the
same exposure to currents, waves and storms as Subaq B. Surface sediments at ST1-14 and ST1-
15 were predominantly sand (77-84%) and gravel (11-20%) with a small silt/clay component (3-
5%). Bulk sediment analysis indicated that no parameters exceeded Category I limits.
WATER QUALITY AND CIRCULATION
Waters in the vicinity of the Subaq B site have been classified as Class SB waters by
MADEP. Specific water quality data is presented in Section 3.0 for the Outer Harbor area.
Typically the greatest impact to water quality in this area is from the numerous discharges and
CSO's originating in the Inner Harbor areas. Water quality improves with increasing distance
from the Inner Harbor.
The fastest tidal currents in Boston Outer Harbor occur in the deep ship channels (up
to 1.4 knots) during spring tides in the southern lane of the Main Ship Channel. The mouth of
Dorchester Channel attains spring tide currents of 0.8 knots on ebb tide and 0.6 knots on flood
tides (Cortell 1990a). Located near the edge of the Main Ship Channel, Subaq B may experience
among the fastest currents.
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Subaqueous Containment Site B (SUBAQ B)
I
Subaq B is exposed and vulnerable to northeasterly storms. The nearest sheltering
landfall is Deer Island (2.0± miles across the harbor). Nearby sediment conditions indicate the
area is occasionally scoured.
AQUATIC RESOURCES
Benthic Infauna
Subtidal benthic macrofauna in the vicinity of the northwest portion of Spectacle
Island were examined during benthic infauna and lobster surveys (Cortell 1990a). .As with other
sampling locations around Spectacle Island, abundances of benthic infauna (retained on a 0.5 mm-
mesh sieve) north of the island were low (1113 individuals/m2). Nematodes, the gastropod N.
trivittatus and the polychaete N. caeca predominated.
Sediment profile camera sampling at Subaq B just south of the shipping channel
revealed a silty substrate covered with a mat ofAmpelisca amphipod tubes (NAI and Diaz 1995).
The depth to the RPD layer was more than 2.0 cm below the sediment surface, suggesting well
oxygenated sediments. There were indications of subsurface bioturbation, including burrows,
worm tubes, and oxic and anoxic voids. Results suggest a healthy benthic community in between
I
pioneering and successional equilibrium stages.
Benthic samples revealed that the amphipod Ampelisca sp. predominated, composing
82% of the total abundance (Table Al-10) Total abundance was the highest of all Outer Harbor
stations (115,149.6/m2), and included 60 taxa. Other species such as spionid polychaete Polydora
cornuta and the amphipod Phoxocephalus holbolli composed a small component of the benthic
community. Results indicate the benthic community is healthy and diverse, intermediate between
disturbed and equilibrium successional stages.
Sediment samples collected during the lobster survey were sieved through a 2.5 mm-
mesh sieve and analyzed qualitatively. The polychaetes Nereidae and Glycera sp., Nassarius sp.
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Subaqueous Containment Site B (SUBAQ B)
and post-larval crabs were the most frequently collected organisms. Soft-shell clam (M arenarid)
spat and razor clams (E. directus) were also encountered.
Lobsters
Lobster fishing activity in the vicinity of Subaq B was examined during the summer
of 1990 for the CA/T project (Cortell 1990a). Pot markers were observed at Subaq B on each
of the three dates examined. Despite being in a navigational channel, pot markers were as
numerous at Subaq B as at other areas around Spectacle Island. Transects were swum by divers
to document use of the substrate around Spectacle Island by lobsters, including EBP lobster. The
greatest density of lobsters was observed off the northeast portion of Spectacle Island (0.0027-
0.0035/ft2). Lobsters occurred at about half that density (about 0.0012/ft2) off the northwest
portion of the island (near Subaq B); abundances elsewhere around the island were generally much
lower. Most lobsters were observed at the deeper portions of the transects. No EBP lobsters were
observed around Spectacle Island; little suitable habitat was encountered for this lifestage.
Recent lobster trapping surveys at Spectacle Island collected low numbers of lobsters
(0.2 per trap-day), one of the lowest in Boston Harbor (Table Al-7). Fishing activity has dropped
dramatically as a result of diminished numbers of lobsters. In the trawl survey, approximately 6.7
lobsters were collected per 20 minute tow, similar to that collected at Subaqueous E (Table Al-4).
Finfish
A recent trawl survey near Spectacle Island collected mainly winter flounder, along
with skate sp., rainbow smelt, and Atlantic silverside (Table Al-4). The number offish (21.3 per
20 minute tow) was among the lowest in Boston Harbor.
Based on the on-going development of the artificial reef design, as required by the
Individual Permit—Landfill Closure and Maintenance at Spectacle Island for CA/T (ACOE no.
199202207; 2/16/93), target fish species in the offshore coastal waters and Boston Harbor areas
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Subaqueous Containment Site B (SUBAQ B)
include forage species such as Atlantic menhaden, Atlantic herring and rainbow smelt, and
predator species such as winter flounder, striped bass, bluefish, pollock, Atlantic cod, tautog and
cunner.
WETLAND RESOURCES
Subaq B is defined as Land Under the Ocean and falls under the jurisdiction of the
Massachusetts Wetlands Protection Act (310 CMR 10.00). By definition, this resource is sup-
i
posed to be significant to the protection of marine fisheries, protection of land containing shellfish,
storm damage prevention, flood control and protection of wildlife habitat. Although food
resources appear to be limited in this area (low benthic infaunal abundances), the area in the
vicinity of Subaq B has been shown to support lobsters and is likely to support winter flounder.
The sandy substrate may provide spawning habitat for winter flounder.
The closest significant shellfish resource to Subaq B is in the vicinity of Governors
Island Flats across the Main Ship Channel to the north of Subaq B where soft-shell clams are
harvested by Master Diggers. The Main Ship Channel influences currents substantially so that
Dorchester Channel has little effect north to Governors Island Flats. The tidal flat on the
southeastern side of Thompson Island also supports a substantial soft-shell clam resource (Cortell
1990b). Shallow bathymetric conditions between the islands and the configuration and orientation
of Spectacle and Thompson Islands result in relatively slow currents passing from Subaq B to the
Thompson Island Flats (0.2 knots, spring flood, Cortell 1990b). Spring flood currents through
the deeper Dorchester Channel (passing north of Thompson Island) are about 0.5 knots.
Located at the mouth of the Dorchester Channel, Subaq B offers little storm damage
protection because its depth is greater than surrounding areas. Storm waves would travel to
shallower areas and crest before reaching land. Because it is in relatively open water, Subaq B
also has little potential for storing flood water.
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Subaqueous Containment Site B (SUBAQ B)
Dissipation of storm waves helps to protect shallower areas, such as the subtidal flat
southeast of Pleasure Bay. Such shallows can be important feeding resources for waterfowl,
including those species observed on and adjacent to Spectacle Island (see next section).
Subaq B is classified as Tidal Waters under federal regulations (33 CFR 328.4(b)).
Tidal Waters may provide sediment/toxicantretention, nutrient retention/ transformation, recreation
and uniqueness/heritage. Subaq B is not likely to contribute substantially to retention of sediments
and toxicants, nor to retention or transformation of nutrients. Relatively swift currents prevent
deposition of fine grained sediments that tend to absorb contaminants. Nearby sediments
contained only low concentrations of metals and organic pollutants. Recreational vessels are
among those using the channel.
WILDLIFE
Waterfowl, including great cormorant (P. carbo), herring gull (L. argentatus), white
winged scoter (M. deglandi), common goldeneye (B. clangula), bufflehead (B. albeold), mallard
(A. platyrhynchos), black duck (A. rubripes), merganser (Mergus spp.) and scaup (Aythya spp.)
have been observed in the vicinity of Spectacle Island (Cortell 1990a). It is likely that these same
species of waterfowl use the Subaqueous B site area for feeding and resting. Each of these
species feed on fish and invertebrates (Martin et al. 1951; Whitlatch 1982; and DeGraaf and Rudis
1986) that occur in the area.
THREATENED AND ENDANGERED SPECIES
No threatened or endangered species listed by federal or state authorities are identified
or anticipated to occur within the boundaries of Subaq B. Several marine mammals not listed as
threatened or endangered, including harbor seals (P. vitulind), harbor porpoise, (P. phocend) and
grampuses (G. griseus), occur occasionally in the area. These species are all protected under the
Federal Marine Mammals Protection Act.
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Subaqueous Containment Site B (SUBAQ B)
HISTORICAL AND ARCHEOLOGICAL RESOURCES
Previous dredging and maintenance of the Main Ship Channel and the Dorchester
Channel have likely disturbed any evidence of historic or archeological remains.
SOCIO-ECONOMIC/LAM) USE
Subaq B is an entirely submerged aquatic site within view of Spectacle Island,
Thompson Island, Fort Independence on Castle Island, Logan Airport and Deer Island. It lies
within a presently marked navigational channel (Dorchester Channel) at its convergence with
Western Way and the Main Ship Channel. Lobstermen fish this area.
This open water site is in the path used by the commuter boats to Boston. The site
is within 1200 feet of Spectacle Island, an abandoned landfill which is being closed and capped
by the Massachusetts Highway Department, and which will be the site of a park owned by the
City of Boston and the Commonwealth Department of Environmental Protection. The site is more
I
than one-half mile from the park at Castle Island, an MDC Park and 0.75 miles from Thompson
Island.
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Subaqueous Containment Site E (SUBAQ £)
2.5.1.2 Subaqueous Containment Site E (Subaq E)
The site is depicted on Figure Al-19.
SEDIMENT CHARACTERISTICS
No sediment data were available for the immediate vicinity of Subaq E. Samples
collected off the end of Logan Runway 33L (Massport 1990) and from Stations E and F in the
Main Ship Channel (ACOE 1988a) may be representative of local conditions. Composed of grey
and black oily fine to medium sand, these sediments contained no constituents whose
concentrations exceeded the range for Category I sediments. Surface material at Stations E and
F in the Main Ship Channel, on the other hand, was >85% silt or clay. Bulk sediment analysis
indicated that most constituents met Category I standards but lead, chromium and volatile solids
occurred at Category II levels.
WATER QUALITY AND CIRCULATION
Water quality in the vicinity of Subaq E is classified as SB. When sampled in 1986,
Class SB standards were met except for occasionally excessive bacterial concentrations (Massport
1990). As water quality conditions have been improving throughout the Harbor it is likely that
this area will continue to meet SB criteria.
As with other sites in Boston Harbor, the hydrodynamics of Subaq E are governed
primarily by tidal currents and secondarily by wind. Bounded to the north and south by shoals,
and in close proximity to the Main Ship Channel, Subaq E is subject to relatively high current
velocities (up to 1.0 knots flood and 1.3 knots ebb in spring tides). This area experiences a 1.0-
mile northeasterly fetch, buffered only by Deer Island, and is exposed to easterly winds. The
adjacent shoals crest waves rapidly. Greater depth offers protection to Subaq E.
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Subaqueous Containment Site E (SUBAQ E)
AQUATIC RESOURCES
Benthic Infauna
Sediment profile camera sampling at Subaq E revealed two habitats. At 4 of the 6
stations, silt substrate was overlain with a matrix of Ampelisca sp. tubes (NAI and Diaz 1995).
The depth of the RPD layer ranged from 1.4-2.0 cm are below the sediment surface, indicating
a healthy degree of sediment oxygenation. There was some evidence of subsurface biological
activity, including an occasional worm tube and anoxic void. Benthic sampling results showed
the amphipod Ampelisca sp. was the dominant organism, composing 45% of the total abundance
of 50,987.5/m2 (Habitat I, Table Al-10). Spionid polychaete.Polydora cornuta and cirratulid
Tharyx acutus composed 18% and 12% of the total communities, respectively. The soft-shell
clam Mya arenaria was collected in low numbers (25/m2, Table Al-10). Two stations at
Subaqueous E had silt substrate, covered either by a matrix ofAmpelisca sp. tubes or a layer of
Adytftus shell hash. Where observed, the RPD layer occurred at 2.5 cm below the sediment
surface. Worm tubes and oxic and anoxic voids were observed underneath the Ampelisca mat,
indicating bioturbation activities at depth. Benthic samples contained low numbers of organisms,
(975/m2, the lowest observed in the Outer Harbor area). The mud snail Nassaritts trivittatus and
polychaete Nephtys cttiata were the most numerous organisms collected, together composing
nearly one half of the sample (Habitat n, Table Al-10). All benthic communities at Subaq E
were intermediate between a disturbed or stressed community and an equilibrium community.
Benthic samples at Subaq E contained low numbers of soft shell clam (M arenaria,
Table Al-10), although this species tends to be most abundant at and slightly above mean low
water. Subaq E is located within approximately 1 nautical mile of the intertidal mud flats, along
i
the perimeter of Logan Airport, which are harvested by commercial clammers. These mudflats
also support extensive beds of blue mussels (M edulis), a species also capable of subtidal
existence.
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Finfish
Subaqueous E
Otter trawl collections in October 1994 collected an average of 82.7 individuals per
20 minute tow, of which 14.7 were lobster (Table Al-4). These catches were the highest of all
stations sampled. Winter flounder and skate sp. each composed approximately one third of the
catch. Rainbow smelt and Atlantic silverside were secondary dominants.
WETLAND RESOURCES
Like Subaq B, Subaq E includes of Land Under the Ocean (under state jurisdiction)
and Tidal Waters (under federal jurisdiction). The Massachusetts Wetlands Protection Act (310
CMR 10.00) assumes that this resource is significant to the protection of marine fisheries, protec-
tion of land containing shellfish, storm damage prevention, flood control and protection of wildlife
habitat.
Differences in bathymetry and currents between Subaq E and adjacent areas are likely
to make it attractive to finfish although it would require more energy to remain hi the stronger
currents of this channel. Regular tidal currents are likely to prevent anoxic or hypoxic conditions
from developing during the summer, enabling finfish to use this area as a refuge from summer
temperatures on the adjacent shoals.
The presence of the channel partially diverts tidal energy away from the adjacent
shoals. The shoals of Governors Island Flats, in particular, are likely to provide soft shell clam
habitat which contributes to the productivity of the area. The abrupt change in depth between
Subaq E and Governors Island Flats makes the southern edge of the Flats susceptible to damage
from waves generated by easterly and southeasterly winds, however winds from these directions
are relatively rare. Governors Island Flats plays a substantial role in protecting intertidal resources
and the shoreline from erosional forces by dissipating waves offshore. Like Subaq B, Subaq E
is located in open water and has no capacity for storage of flood waters.
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Subaqueous Containment Site E (SUBAQ E)
Classified as Tidal Waters under federal regulations, Subaq E was evaluated for its
ability to provide the functions of sediment/toxicant retention, nutrient retention/transformation,
recreation and uniqueness/heritage. Because tidal currents tend to be elevated in channels and
keep fine-grained sediments in suspension, it is unlikely that Subaq E contributes to sedi-
ment/toxicant retention or nutrient retention/transformation. However, its proximity to commercial
anchorages exposes Subaq E to potential spills and accidental discharges. This area is used by
recreational boaters for passage into Boston Harbor.
WILDLIFE
Waterfowl, including great cormorant (P. carbo), herring gull (L. argentatus), white
winged scoter (Melanitta deglandi), common goldeneye (B. dangula), bufflehead (Bucephala
albeold), mallard (A. platyrhynchos), black duck (A. rubripes), merganser (Mergus spp.) and scaup
(Aytka spp.) have been observed in the vicinity of Spectacle Island (Cortell 1990a). It is likely
that these same species of waterfowl also use the Subaqueous E site for feeding and resting. Each
of these species feed on fish and invertebrates (Martin et al. 1951; Whitlatch 1982; and DeGraaf
and Rudis 1986) that occur in the general area.
THREATENED AND ENDANGERED SPECIES
No federally or state-listed threatened or endangered species are identified or expected
to occur within the vicinity of Subaq E. All marine mammals are protected under the Federal
Marine Mammals Protection Act, whether threatened/endangered or not. Three species, harbor
seals (Phoca vitidind), harbor porpoises (Phocena phocend) and grampuses (Grampus griseus)
occur occasionally in the harbor.
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mSTORICALAND ARCHEOLOGICAL RESOURCES
There are no listed historical or archeological resources at the Subaq B or Subaq E
sites.
SOCIO-ECONOMIC/LAND USE
Current use of Subaq E is for navigation between Winthrop Harbor and Boston Harbor
(approximately 20 feet MLW). Although entirely submerged, disposal activities at Subaq E would
be visible from Deer Island, Winthrop Harbor, Logan Airport, Fort Independence (Castle Island),
Spectacle Island and Long Island during construction. Height restrictions may occur because of
its proximity to Logan.
This open water site abuts General Anchorage Areas to the south and east and is in
the path of the ferries carrying construction personnel to Deer Island during the Boston Harbor
Clean-up Project. It is farther removed from the parks discussed with regard to the Subaq B site.
2.5.2 Environmental Consequences of using Subaqueous Containment Sites for
Dredged Material Disposal
In order to use either Subaqueous B or E for disposal of silt from the BHNIP, berms
(composed of parent material) closing off their open sides would have to be constructed. This
berm construction would constitute the extent of site preparation. The nature of these sites would
preclude the possibility of filling them in discrete cells. When disposal was complete, the entire
area would be capped with sand.
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SUBAQUEOUS B
Subaqueous B is located at the mouth of the Dorchester Channel. It is a triangular
area with gradually sloping bathymetry to the west and south and open to the Main Ship Channel
to the northeast. It has an estimated capacity of 609,000 cy. Including the proposed cap, use of
this site for disposal of dredged materials from Boston Harbor would raise the substrate to a final
depth of approximately -15 ft MLW.
Direct Impacts
Use of Subaqueous B would permanently cover an 83-acre footprint that was found,
in the fall of 1994, to support high abundances of benthic infauna. The predominant organism
present in the benthic community was a tube-dwelling amphipod (Ampelisca sp.) that is known
to be an important prey item for juvenile flounder. This community would be covered and it is
unlikely that these organisms could recolonize before disposal was complete. Assuming a sand
cap were used to close the site, recolonization would occur. Although use of this site would result
in a permanent reduction in depth, it is unlikely that this would have a major effect on the benthic
community. It was observed in the fall of 1994 that the benthjc community structure at
Subaqueous B was very similar to that to the east of Spectacle Island (at Spectacle Island CAD),
where water depth ranges from -8 to -12 ft MLW.
Alteration hi bathymetric conditions at this site could affect finfish by reducing the
bathymetric diversity. During warm summer months, finfish seek cooler waters in deeper areas.
A change in depth of 10 feet could make a significant difference in water temperature in the
summer at this location.
Either a sand or a clay cap would represent different sediment characteristics than are
present at the site now. Because of the local hydrodynamics, it is unlikely that the cap would
become heavily silted. Hydrodynamic conditions also indicated that armoring the cap with rock
would be necessary. In this case, substrate conditions would change markedly from existing
conditions. The rock would support a very different benthic community from that currently
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Subaqueous Containment Site E (SUBAQ E)
present. As hard substrate is rare subtidally in Boston Harbor, a rock armor would add to habitat
diversity in the outer harbor. Shallow rocky subtidal habitat can be highly productive (as the
existing habitat appears to be) and support finfish and epibenthic crustaceans. Interstitial spaces
between the rocks would tend to accumulate any fine-grained sediments that were transported to
the site. These micro-habitats could support soft-substrate benthic species.
Lobster pots were observed in this area in the summer of 1990 (Cortell 1990).
Disposal activities would prevent use of the site for the duration of the BHNIP, but closure of the
disposal area would allow lobstermen to fish the area in the future.
Indirect Impacts - Water Quality Effects
Analysis of the mixing zone requirements for disposal at Subaqueous B indicated that
total suspended solids would be the limiting parameter. After steady state (achieved within about
five days of repetitive disposal) is reached, a single disposal event at or around high tide would
require a mixing zone of about 26.8 acres (555m by 195 m; Appendix F) before TSS reached a
level of 50 mg/L. Disposal at high tide would cause the mixing zone to be oriented along the
Main Ship Channel towards the mouth of the Outer Harbor. Dredging for the BHNIP would not
interact with the disposal plume at this site.
Repetitive disposal events should have little impact on the water quality of the Outer
Harbor (see Appendix F). Assuming daily disposal events, concentrations of total suspended
solids and dissolved contaminants would increase for up to a 20-30 day period, and then reach
equilibrium. A pollutant transport model analyzing daily disposal of silt at Subaqueous B
indicated that, at equilibrium, the maximum concentration of all constituents of concern would be
well below the chronic water quality criteria (Table Al-17).
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Subaqueous Containment Site E (SUBAQ E)
Indirect Impacts - Site Stability
As described for the In-Channel disposal scenario, it is unlikely that upward migration
of contaminants through the cap would occur.
Subaqueous B is exposed to erosional hydrodynamic conditions from several sources.
Flood and ebb tidal currents exceed speeds of 1.0 ft/sec during spring tides (i.e., at least twice
monthly), sufficient to erode silt or sand. Because this site is located within the Dorchester
Channel and immediately adjacent to the Main Ship Channel, it is likely that the substrate is
exposed to propeller wash from passing ships and boats on a frequent basis and that this would
be sufficient to erode material either during disposal or after the cap has been placed. In
addition, this site is exposed to storms from the east and northeast. It has been predicted that
storms with a frequency of one year could produce bottom currents of up to 0.6 ft/sec (20
cm/sec), sufficient to resuspend silt or sand. Therefore, several hydrodynamic conditions combine
to make the stabilization of this site difficult in the short or long term.
Indirect Impacts - Downstream Resources
Downstream biological resources of concern include soft-shell clams, Ampelisca beds,
winter flounder (in particular, but all finfish occupying the Outer Harbor), and lobsters.
Recreational areas include Pleasure Bay, Castle Island and Spectacle Island (the latter park is
scheduled to open in 2000). Distribution of clam beds in Boston Harbor is shown in Figure
Al-22. Most of the clam beds within one mile of Subaqueous B are currently closed to any type
of harvesting, however, it is expected that this status may change with the continued clean up of
the Harbor.
The pollutant transport model indicated that transport of silt into these intertidal areas
[
would be unlikely. Silt released into the water column would be most likely to settle to the
substrate within about 80 m of the point of disposal in a layer about 0.2 cm (0.5 in) thick.
Because of the dimensions of the disposal site, most events would not result in deposition of
substantial quantities of vagrant silt outside the disposal site footprint itself. Tidal flow would be
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Subaqueous Containment Site £ (SUBAQ £)
likely to resuspend this material and prevent further accumulation. However, repeated disposal
events could result in temporarily reduced benthic productivity in up to 36 acres (a 240-ft wide
band surrounding the disposal site).
Recent surveys of benthic communities in the outer harbor have found that the tube-
dwelling., mat-forming amphipod Ampelisca is a predominant species in most areas examined.
Its high abundances appear to be a recent phenomenon that has been linked with the elimination
of the sewage sludge discharge from Deer Island. Although this amphipod occupies silty
sediments, it requires good water quality conditions. It is unlikely that the minor increase in
suspended sediments (7 mg/L above ambient) would affect the existing population of Ampelisca
or recruitment of juveniles to this area. Any effect would probably be temporary, limited to the
disposal period and perhaps six months to a year afterwards (to account for the reproductive cycle
of Ampelisca).
One of the critical functions that Ampelisca beds play is in providing food for juvenile
winter flounder. Because juvenile winter flounder are thought to have very small ranges (on the
order of 100 m or so), loss of a 36-acre area of Ampelisca bed could be deleterious to winter
flounder during the project's construction phase. Finfish sampling has not been conducted in the
immediate vicinity of Subaqueous B, although it is assumed finfish use is similar to that observed
at Subaqueous E (an area of relatively high catches in fall 1994).
As an estuarine species, winter flounder does adapt to periods of high turbidity.
Therefore, the dispersion of sediments released during dredged material disposal may have no
immediate impact on the distribution of post-juveniles. However, if food resources are destroyed,
those lifestages of greater mobility would be likely to move out of the area. If winter flounder
spawned in the immediate vicinity of the disposal site, the eggs would potentially be subjected
to higher mortality because of elevated sedimentation.lt is unlikely that the minor increase in
suspended solids would affect either lobsters or lobster fishing. A concentration of 7 mg/L or less
would not be visible.
Various recreational activities occur or are planned in the vicinity of Subaqueous B.
Pleasure Bay and Spectacle Island are the closest recreational areas to this disposal site. Pleasure
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Subaqueous Containment Site E (SUBAQ E)
I
Bay has both a swimming beach and a sailing school. Spectacle Island is planned for general
recreation, including swimming, fishing, picnicking and hiking. Disposal activities would be
visible from these areas and Castle Island, although no plume would be apparent. Contact with
PAHs is a concern for human activities. The most soluble compound, naphthalene, does not have
known carcinogenic properties. Because its dissolved concentration is predicted to be < 2.0 ng/L
in areas where human contact could occur (e.g. Spectacle Island swimming beach), it is unlikely
that any dissolved PAHs would occur at levels of concern. It is unlikely that the disposal activities
would interfere or pose any risk to recreational pursuits.
Indirect Impacts - Biological Exposure Potential
Water Column Exposure
Hydrodynamic conditions in the vicinity of Subaqueous B create a dispersive
environment, conducive to rapid dilution and transport of water-borne contaminants. Water
quality modeling of the material to be disposed indicated that none of the contaminants of concern
would reach concentrations within an order of magnitude of the chronic water quality criteria.
As ambient water quality in the Outer Harbor has improved substantially since elimination of the
Deer Island sewage sludge discharge, it is unlikely that water quality conditions created by
disposal of BHNIP silts at Subaqueous B would cause discernible effects in biota exposed in the
water column.
Substrate Exposure
Because of the frequency with which disposal activities would take place (one to four
times per day), it is unlikely that benthic organisms would be recruited to this disturbed substrate
until disposal was complete. In particular, bioassay test results indicate that it is unlikely that
Ampelisca recruited to the recently disposed sediments could survive. Therefore, there would be
little or no opportunity for these infaunal organisms to accumulate contaminants. The absence of
infauna, as well as the frequent disposal events, would deter benthic-feeding fish and crustaceans
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Subaqueous Containment Site E (SUBAQ E)
from spending extended periods associated with the disposed dredged material prior to isolation.
As with the In-Channel disposal scenario, the limited downstream areas subject to
sedimentation could have a higher potential for exposing demersal organisms to contaminants.
The hydrodynamic conditions in the vicinity of Subaqueous B would tend to cause recently
deposited (i.e., uncompacted) sediments in downstream areas to become resuspended and
redistributed frequently. Coupled with the fact that the size of the site would require that the
dredged material be disposed at multiple locations, it is unlikely that dredged silts dispersed
beyond the disposal site would build up on the substrate in a particular area. Sedimentation would
not be apparent after cessation of disposal and capping of the site.
Organisms inhabiting the areas subject to temporary sedimentation could be impacted
by the half-inch layer of vagrant silt. This layer would contain higher concentrations of
contaminants than are presently in the proposed disposal area. Areas exposed to this deposition
could experience contaminant-induced elevated mortalities ofAmpelisca if the silt was present for
at least several consecutive days. It is unlikely that this material would remain in place for a
sufficient length of time to allow bioaccumulation by other infaunal benthic species. Winter
flounder foraging in the area could ingest come sediment as they grazed on Ampelisca. In
addition, their habit of burying themselves in the sediment would increase the likelihood that
winter flounder could experience adverse effects caused by dermal contact, if they remained in
the areas subjected to repeated sedimentation.
Other Issues
The proposed project should not adversely impact species considered threatened or
endangered by the USFWS, NMFS or MANHESP. Several species that are protected under the
Federal Marine Mammals Protection Act (e.g. harbor seals, harbor porpoise) occasionally do occur
in this area; these also should not be adversely impacted by the Project.
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Subaqueous Containment Site E (SUBAQ E)
The proposed project should have no effect upon any structure or site of historic,
architectural or archeological significance as defined by MHC or the National Historic
Preservation Act of 1966, as amended.
The disposal operations of silt material would involve approximately 450 barge trips.
This would result in some delays to commercial and recreational boat traffic using the Harbor.
Construction activities would have a minor adverse aesthetic impact, and result in slightly elevated
noise levels. The proposed project would be unlikely to have a long-term impact on the soft-shell
clam fishery in the vicinity of the site.
If filling is to an elevation below the surrounding bathymetry, there would be no
permanent impact harmful to the recreational boaters in this area or to commuter boat traffic using
this route to Boston's Inner Harbor. The act of placing the material may disrupt boating activity
but only to the extent of requiring vessels to travel around the barge placing the sediments.
SUBAQUEOUS E
The proposed disposal site Subaqueous E is located north of the Main Ship Channel
and west of Presidents Roads Anchorage. The site is a rectangular area that forms a depression
between Governors Island Flats and Lower Middle. Subaqueous berms would have to be
constructed along the east and west ends of the site to contain the silts during disposal. It has an
estimated maximum capacity of 614,000 cy of silt. Including a cap, the site would be filled to
a final depth of-8 ft MLW.
Direct Impacts
Direct impacts associated with use of Subaqueous E would be the same as those
described for Subaqueous B. The 79-acre footprint of Subaqueous E supports an abundant and
diverse benthic infaunal community, dominated by Ampelisca . Reestablishment of this
community would be possible, because the final depth is within the range that was observed to
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support this community in the fall of 1994, but it would be dependent on the quality of the final
cap. A clay cap could require an extended period of exposure and colonization by pioneering type
species before it was suitable for colonization by later successional stages. A sand cap could be
more quickly colonized, depending less on physical reworking than the clay cap. However,
because of its exposure to tidal currents and storm wave effects, it could be necessary to armor
the cap with rock. As with Subaqueous B, a rocky cap could increase the diversity of productive
substrate in the outer harbor.
The reduction in depth at Subaqueous E would be unlikely to have an affect on the
quality of the benthic community that could exist It could affect finfish use because it would
diminish the small-scale diversity in bathymetry that presently exists, eliminating a potential cooler
water refuge during summer months.
Indirect Impacts - Water Quality Effects
The mixing zone around the disposal process at the Subaqueous E site would be best
defined by the area needed to dissipate total suspended solids loads to <50 mg/L. Sediments
dissipating from the disposal operations at this location would not commingle with sediments
escaping the dredging process. Based on disposal at or around high tide, the necessary mixing
zone would occupy about 18.0 acres (355m by 210m) and be oriented towards the mouth of the
Outer Harbor.
Pollutant transport modelling indicated that released sediments and dissolved
contaminants would be rapidly diluted and dispersed. Maximum concentrations predicted after
29 days of daily disposal are listed in Table Al-18.
Indirect Impacts - Site Stability
Subaqueous E would be developed as one large cell. Therefore, all silt disposed at
this site would be exposed to prevailing hydrodynamic conditions until the final cap was placed,
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a period of about 18 months. As this site is outside of all designated channels, marine traffic is
limited to small boats (fishing and recreational vessels) passing through this area in route to the
Winthiop Harbor boat ramp and yacht club. These shallow-draft vessels are unlikely to create
bottom currents capable of eroding sediments from this site. However, tidal currents at
I
Subaqueous E are estimated to reach up to 2.2 ft/see (67 cm/sec) on spring ebb tides (slightly
lower on flood tides). Although Subaqueous E is located in the lee of Deer Island during
northeasterly storms, it is exposed to storms from the east. A one-year storm from this direction
could generate bottom currents as high as 0.9 ft/sec (30 cm/sec). Either of these conditions could
resuspend and disperse dredged materials disposed at the Subaqueous E site. In fact, these
conditions are sufficient to jeopardize the stability of either a sand or clay cap, presenting a long-
term risk to the integrity of the disposal site. Therefore, it would be necessary to armor the cap
with rock blasted during the dredging of an area at the mouth of Reserved Channel and in the
Inner Confluence.
As with other sites described, it is unlikely that contaminants would migrate upwards
through the cap. Therefore, since the rock armoring would ensure that the cap stays in place,
containing the disposed silts, it is highly unlikely that there would be additional water quality
impacts after the site is closed.
Indirect Impacts - Downstream Resources
Resources of concern in the vicinity of Subaqueous E include soft-shell clam beds,
Ampelfsca beds, winter flounder, lobster and recreational fishing. The extensive and highly
productive soft-shell clam flats along the shoreline of Governors Island are conditionally open to
harvesting (Master Diggers).
The pollutant transport model indicated that most vagrant silt would settle within 80
m of each individual disposal event and reach a maximum thickness of about 0.23 cm (0.6 in).
Disposal events centered over about half (32 acres) the area of the site could result in detectable
sedimentation outside the defined site footprint. Based on the site configuration, this could affect
I
an area of about 50 acres beyond the footprint of the site. As with Subaqueous B, tidal currents
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Subaqueous Containment Site £ (SUBAQ £)
could resuspend this material rapidly and prevent further build up, although, repeated disposal
events could introduce sediments frequently enough to cause a temporary reduction in benthic
productivity. These deposited sediments would have higher contaminant concentrations than
existing sediments.
Impacts to Ampelisca beds, winter flounder and lobster would be the same as
discussed for Subaqueous B, although, of course, the impacts would occur in the area in the
vicinity of Subaqueous E. This area is shown on Appendix TV. It is unlikely that there would
be detectable levels of sedimentation on the clam flats.
Presence of the disposal operation may deter recreational fishermen from fishing in
the area whether or not there is visual evidence of disposal (i.e., any plume).
Indirect Impacts - Biological Exposure Potential
Water Column Exposure
Like Subaqueous B, hydrodynamics at Subaqueous E create a dispersive environment.
Water quality modelling predicted that there would be no excessive buildup of dissolved
contaminants. Therefore, it is unlikely that pelagic organisms would be exposed to contaminant
levels that would be deleterious to them during disposal operations at Subaqueous E. Water
quality at the clam beds would reflect ambient conditions.
Substrate Exposure
As at Subaqueous B, the routine disposal events would tend to preclude colonization
of BHNIP silts until the final cap has been put in place. The absence of food resources and the
frequent disturbances at the site would be likely to cause finfish and epibenthic crustaceans from
spending prolonged periods of time at the site until the site has been closed. Therefore, it is
unlikely that organisms would be exposed to the BHNIP silts and their associated contaminants
long enough to bioaccumulate contaminants.
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Subaqueous Containment Site E (SUBAQ E)
Because the transport of resuspended sediments to downstream areas would be less
dramatic than the descent of dredged materials at Subaqueous E, organisms would not be likely
to avoid these areas. The sediment-bound contaminant loading described for Subaqueous B would
also apply to this site. It is unlikely that hydrodynamic conditions would allow the creation of
identifiable deposits of BHNIP silts released during disposal operations.
Other Issues
The proposed project should not adversely impact any species considered threatened
or endangered by the USFWS, NMFS and MANHESP. Several species that are protected under
the Federal Marine Mammals Protection Act (e.g. harbor seals, harbor porpoise) occur
occasionally in this area; construction activities should discourage them from frequenting the
immediate project site, thus reducing potential impacts.
The proposed project would have no effect upon any structure or site of historic,
architectural or archeological significance as defined by MHC or the National Historic
Preservation Act of 1966, as amended.
The disposal operations would involve approximately 423 barge trips. This would
result in some delays to commercial and recreational boat traffic using the harbor. Construction
activities would have a minor adverse aesthetic impact, and result in slightly elevated noise levels.
Any fishing (for lobster, etc.) in the immediate disposal area would have to be curtailed during
the disposal period.
If filling occurs to the depths of the surrounding area, there will be no permanent
impact on marine traffic. However, during the installation of the material, any marine vessels
must circumvent this area to minimize interference with the placement operation.
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Massachusetts Bay Disposal Site (MBDS)
2.6 SITE EVALUATIONS: EXISTING
AQUATIC DISPOSAL SITES
2.6.1 Massachusetts Bay Disposal Site (MBDS>
This site is depicted in Figure A1-21.
2.6.L1 Existing Conditions
SEDIMENT CHARACTERISTICS
The physical properties of the substrate near the disposal point is varying in
composition, predominantly sandy silt, reflecting the various harbor dredging projects disposed
here. The natural bottom covering the majority of MBDS (i.e. areas of the silt that have not
received dredged material) is a fine silt/clay substrate (ACOE NED unpublished data). The
composition of this natural material indicates the basin is a depositional area capable of containing
the dredged material. If sufficient currents frequented this area of the basin, the fine grained
material would be suspended and transported with the currents. Areas of high current velocities
would therefore have a coarse grained (heavier than silt/clay) substrate, a substrate that is not
typical of this basin, but is present in the shallow (approximately 60 meter deep) northeast
quadrant of MBDS. This area is a rock/cobble/sand area, at the 60 meter isopleth relief west of
Stellwagen Bank.
The EPA (1989) evaluated the sediment composition of the MBDS in their draft EIS
to evaluate the continued use of the MBDS. The results of the metals analysis show that metal
concentrations in the MBDS are either Class I (low) or Class II (moderate) according to the
Massachusetts Division of Water Pollution Control guidelines for dredged material. In general
these results were similar to levels found outside the disposal site in Massachusetts Bay (EPA
1989). Petroleum hydrocarbons were detected at a higher level within the MBDS than outside.
However, polyaromatic hydrocarbons, a measure of the aromatic fraction of petroleum
hydrocarbons, was more varied inside than outside the disposal site. Polychlorinated biphenyls
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Massachusetts Bay Disposal Site (MBDS)
(PCBs) levels on dredged material are somewhat higher than ambient levels. PCB levels detected
in dredged material in the vicinity of the MBDS are comparable to levels identified in other
Massachusetts Bay studies (EPA 1989).
WATER QUALITY AND CIRCULATION
The oceanography of MBDS is influenced, in part, by the circulation of the Gulf of
Maine (SAIC 1993). The Gulf of Maine circulation patterns in the vicinity of the MBDS are
modified to a large extent by the presence of Stellwagen Bank on the eastern margin of the
Massachusetts Bay. The bank interferes with the exchange of water at depth with the Gulf and
the shelf beyond. Stellwagen Bank is a popular fishing and whale watching area. This area was
designated as a National Marine Sanctuary on November 4, 1992. The MBDS is located outside
the boundary of the Stellwagen Bank National Marine Sanctuary.
Results of MBDS oceanographic studies indicate that the site is located in a low
energy, deep water environment, allowing containment of dredged material within the site.
Physical oceanographic studies conducted by ACOE NED under the Disposal Area Monitoring
System (DAMOS) program as well as those by other investigators have shown that the bottom
current velocities at the disposal site are quite low, averaging less than 7 cm/s (Butman 1977;
Gilbert 1975; SAIC 1987 and SAIC 1993). This is in general agreement with the current data
collected for disposal of dredged material at the MBDS from the construction of the CA/T (EA
Engineering, Science, and Technology 1992). Occasional higher velocities, near 20 cm/s in a
westerly direction, have been observed in near bottom waters in response to easterly storm events
that occurred in fall and winter. Near-bottom currents of this magnitude were not predicted to
be strong enough to resuspend sediments at MBDS (EPA 1989).
i
!
The temperature/salinity cycle of Massachusetts Bay is characterized by seasonal
variability, with maximum temperatures (18°C at surface) typically occurring in a stratified water
column during August and September, and minimum temperatures (5°C) typically occurring in
an essentially isothermal water column in January and February (SAIC 1987). Salinity values
range from 31-33 ppt (SAIC 1987).
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Massachusetts Bay Disposal Site (MBDS)
AQUATIC RESOURCES
Benthic Infauna
Sampling of the benthos at the MBDS (SAIC 1986) described three distinct
community assemblages as occurring. These assemblages reflect the various sediment regimes
within the site.
The northeast section of the site has an unimpacted coarse sand and gravel com-
position. The benthic community, when sampled in the fall of 1985, was numerically dominated
by the Syllidae polychaete Exogone verugera profunda (907/m2); the Paraonidae polychaete
Levmsenia gracilis (350/m2); and the Spionidae polychaete Prionospio steenstrupi (313/m2). A
total of 105 species averaging 4,433 organisms per square meter were recovered.
Rock from the CA/T project was deposited in the northern section of the MBDS. The
rock was placed away from the main disposal activity to allow a benthic community to develop
providing prey for finfish.
The western portion of the MBDS has been impacted by continued disposal of
dredged material from the greater Boston region. Approximately three million cubic yards of
dredged material has been disposed in this section of MBDS. This continual disturbance of the
bottom maintains the community of benthic organisms in a dynamic equilibrium. The most
adaptable species proliferate. Those species that reproduce rapidly and have high numbers of
offspring (i.e., larvae) colonize the newly disposed dredged material (r-strategists of classical
ecology) and biogenically rework the substrate. Given time, this pioneering community would
alter the sediment character and allow a more mature community to develop. The frequent
disposal activity maintains the resident population of the disposed material area as a pioneering
sere. This assemblage at MBDS was dominated (in fall 1986) by oligochaetes (6,293/m2); the
Spionidae polychaete Spio pettibonae (4,607/m2); the Cirratulidae polychaete Chaetozone setosa
(2,160/m2); and the Capitellidae polychaete Metiomastus ambiseta (1,757/m2). A total of 78
species averaging 25,467 organisms per square meter were recovered.
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Massachusetts Bay Disposal Site (MBDS)
The southeastern section of MBDS has an unimpacted silt/clay sediment make-up.
The lack of physical disturbance (burial) by disposal of dredged material has allowed a mature
benthic assemblage to become established. Interspecific competition within a mature community
results in a presence of considerably lower densities of individuals (e.g. 8,390/m2) than found in
continually disturbed habitats (e.g. 25,467/m2). The undisturbed southeastern section of MBDS
was dominated by the Paraonitae polychaete Levinsenia gracilis (1,583/m2); oligochaetes
(1,050/m2); and the Capitellidae polchaete Mediomastus ambiseta (693/m2). The fall 1985
sampling in this section of MBDS recovered a total of 57 species averaging 8,390 individuals per
j
square meter.
The August 1990 bathymetric and REMOTS sediment profile surveys conducted at
MBDS confirmed that the dredged material formed a deposit one meter high at the mound center
(SAIC 1993). Despite the large amount of material (over 340,000 cubic yards) deposited at the
site since November 1988, the REMOTS photography indicate a steady recovery of the benthic
ecosystem. This was indicated by a steady increase in Stage HI taxa (large burrowing deposit
feeders, i.e. climax community) (SAIC 1993).
Various finfish species have been collected within the MBDS (SAIC 1986, SAIC
1985, EPA 1989). In the spring of 1985, the spiny dogfish was the dominant finfish recovered.
This species migrates seasonally in large schools. Those sampled at MBDS were found to be
feeding on flounder, sculpin, and anemones. Fall 1985 finfish collections were dominated by the
witch flounder or grey sole and the dab or American plaice. The former was found to be foraging
on polychaetes (e.g. Chaetozone sp.; Spio sp.; Stemapsis sp. and Tharyx sp.). The latter was
found to be foraging on brittle stars (Ophiuroidea). Other important species include redfish, ocean
pout, cusk, and Atlantic wolffish. Silver and red hake are abundant, commercially important
seasonal migrants.
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Massachusetts Bay Disposal Site (MBDS)
WETLAND RESOURCES
There are no protectable wetland resources subject to federal or state jurisdiction at
MBDS.
Approximately 35 species of marine mammals, 5 species of marine turtles and 40
species of seabirds occur within the Gulf of Maine. Aerial surveys were conducted for the ACOE
to assess the use of the Massachusetts Bay Disposal Site (MBDS) by marine mammals, reptiles
and seabirds.(MBO 1987).
Seabirds observed include northern fulmar (Fulmanus glacialis), shearwater (Pujfinus
sp.), storm petrels (Hydrobatrae), northern gaumentXS'tfa bacsaus), Pomarine jaeger (Steriovarius
pomarinum), gulls (Larinae) and Alcids (Alcidae). Dominant nonendangered mammals include
minke whale (Belasnoptera acutorostratd), white-sided dolphin (Lagenorhynchns acutus), and
harbor porpoise (Phocena phocend). Although five species of turtles potentially could occur on
Massachusetts Bay, only the leatherback turtle (Dermochelys coriacea) is typical in the area.
THREATENED AND END ANGERED SPECIES
MBDS is located in Massachusetts Bay, an area known to be utilized by various
marine mammals, but outside (just west of) the boundaries of the Stellwagen Bank national marine
sanctuary. Endangered whale species are known to congregate above the shallow (30 meter)
Stellwagen Bank (U.R.I. 1981) when foraging for prey (e.g. sand lance Ammontytes americanus).
These species also have been observed within the two nautical mile circular boundary of the
MBDS. Endangered species identified as transients of MBDS include the finback whale
Balaenoptera physalus; the sei whale Balaenoptera borealis; the humpback whale Megaptera
novaeangliae and possibly the northern right whale Eubalaena glacialis (MBO 1987). The impact
of the use of the MBDS on endangered species is currently being assessed by the ACOE NED.
Use of the site to date has not indicated any impact to threatened or endangered species. Full
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Massachusetts Bay Disposal Site (MBDS)
coordination with the NMFS ensures compliance with the protection of endangered species and
their habitats.
Cetaceans are transients of the disposal site, but are not likely to be to impacted by
ocean disposal. Some threatened or endangered turtles (i.e., leatherback, Kemp's ridley and
loggerhead) have been recovered in this region as well. If any transient endangered species
entered the area during the project operation, they should be able to avoid the dredging or disposal
activity. Disposal of dredged material at the MBDS is not expected to have an adverse impact
on endangered species, their prey, or the habitat essential for their survival. Consultation with
the NMFS under Section 7 of the Endangered Species Act of 1973 (as amended, 16 U.S.C. 153 1
etseqX has been initiated to ensure this activity will not jeopardize any endangered or threatened
species.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
The MBDS has been used for disposal of dredged material since the 1940's. No
historical or archeological resources are expected to occur atJhe site. Consultation with EPA
during the designation of the MBDS with the Massachusetts Board of Underwater Archeology
indicated that no known historical shipwrecks exist at or near the site.
SOCIO-ECONOMIC/LAND USE
MBDS is an active disposal site that has been in use for several decades. Extensive
shipping, fishing, recreational activities, and scientific investigations take place in Massachusetts
• Bay year around. There are no known interferences from disposal events on these activities (EPA
ROD 1993). In addition, the availability of the MBDS for the vast majority of sediments from
Boston Harbor provides an engineering, social, environmental, and economic solution for the
disposal of such a large amount of material.
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Massachusetts Bay Disposal Site (MBDS)
2.6.1.2 Environmental Consequences
SEDIMENT CHARACTERISTICS
MBDS has been extensively studied by the ACOE NED. Precision bathymetry,
sediment grab sampling and REMOTS image analysis (sediment profiling) have characterized this
site as a low energy environment suitable for dredged material disposal and containment.
Additional oceanographic sampling has been conducted to designate MBDS as an ocean dredged
material disposal site.
The MBDS is the only U.S. EPA designated dredged material disposal site in the
Boston Harbor/Massachusetts Bay area. This site annually receives approximately 300,000 cubic
yards of dredged material with the exception of this project. However, this figure is expected to
decrease for two reasons. First, more stringent biological testing for open water disposal of
dredged material means more material will not be acceptable for open water disposal. In addition,
the recent designation of the MBDS by EPA states that no capping of unsuitable material is
allowed at the MBDS until it can be demonstrated that capping can isolate unsuitable material
from the benthic community. Until this can be demonstrated to the satisfaction of the EPA and
other appropriate agencies, capping would not occur. Since much of the silt material dredged
from the Boston Harbor area is unsuitable, this site would be used primarily for parent material.
The ACOE NED has successfully completed many capping projects in New England and believes
capping is a viable option at the MBDS. Although no capping of unsuitable material will occur
for the Boston Harbor navigation improvement project at the MBDS, questions raised by EPA
about capping are addressed hi Appendix F. Future use of the site may be considered if the
efficacy of capping can be demonstrated.
Approximately 2.0 million cubic yards of dredged material (parent material) could be
disposed at the MBDS. The material dredged from the proposed channels will be placed on
barges and transported (approximately 1500 trips) to MBDS. The disposal will occur by bringing
the barge to a complete stop at the predescribed point. This disposal point will be marked by a
buoy positioned by the ACOE NED. The discharge will occur in approximately 100 meters of
water.
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Massachusetts Bay Disposal Site (MBDS)
WATER QUALITY AND CIRCULATION
A turbidity plume will be created by the disposal of the dredged material. During
descent, some of the fine-grained sediment separate from the plume and remain in suspension.
The amount of material that is dispersed in the disposal plume is dependent upon the physical
characteristics of the sediment, the volume of material disposed, and method of disposal, and
typically ranges from 3 to 5% (WES 1986).
Recent studies (SAIC 1985) concluded that the concentration of suspended materials
in the turbidity plume, following disposal, will be no greater than 5 to 12 mg/1 forty minutes after
disposal. These studies were conducted at the MBDS with hydraulically dredged material
disposed in 100 meters of water. This method of dredging mixes the sediment with water to form
a slurry. The disposal of this mixture represents the maximum possible suspension of material.
The bucket dredging technique to be used for this project will maintain the disposal sediments in
a cohesive mass, greatly reducing turbidity potentials.
Dredged material which settles on the bottom at MBDS can be expected to remain in
place. Near bottom currents are low, averaging less than 7 cm/s (EPA, 1989). Resuspension from
storm events is rare and typically results in resuspension of only 4% of the surficial material.
As the material descends through the water column, some of the chemicals adsorbed
to the fine particulates may be eluted from the dredged material. The. concentration values in the
turbidity plume will be considerably less than the bulk chemistry concentrations in the dredged
material, since most of the material will remain consolidated. Due to the low natural levels of
metals and other chemicals in the clay, the water quality impact, if any, will be contained within
the disposal site. EPA determined that water quality impacts from disposal events are temporary
and limited to the period immediately following the disposal (EPA 1989).
Recent studies (EPA 1993) for the MWRA offshore outfall impacts evaluated water
quality impacts at MBDS from the BHNIP, using the ADDAM's model with input assumptions
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Massachusetts Bay Disposal Site (MBDS)
and data from this study. In that report, EPA found no water quality criteria exceedances outside
the mixing zone (disposal site) for the MBDS after four hours.
Physical parameters such as currents, waves, and tidal circulations have been closely
monitored for the site (SAIC 1985). This area has contained dredged material on site and does
not disperse sediment or chemicals to affect ambient environments. In general, the proposed
disposal of an estimated 1.8 million cubic yards of material dredged from the project area will not
significantly impact the disposal site given its physical, chemical and biological characteristics and
general history of use.
AQUATIC RESOURCES
Benthic Infauna
The disposal site has been used for dredged material disposal for a number of years.
Disposing sediments at site buries the organisms inhabiting the impact area. This burial process
has been of sufficient frequency at MBDS to maintain a disturbed environment at the point of
disposal. A specialized population of benthic species have successfully exploited this disturbed
niche and rapidly provide biomass and bioturbation to the newly disposed material. These
pioneering organisms are already established on the disposal site (SAIC 1985) and their action can
quickly rework the newly deposited sediments. The disposal of dredged sediments would bury
non-motile and larval/juvenile organisms at MBDS. The same pioneering species can quickly
inhabit the newly disposed material by larval and adult recruitment. The overall process of
maintaining a disturbed habitat would provide a productive benthic environment for organisms that
rework the substrate. This biological mining of the substrates (bioturbation) homogenizes and
oxygenates the upper few centimeters of the sediment. This can allow other organisms to begin
inhabiting the substrate (colonization). Larvae settle and metamorphize and adults emigrate into
the area, all contributing to restore benthic productivity.
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Massachusetts Bay Disposal Site (MBDS)
Disposal of dredged material will have a temporary impact on finfish at the site.
Adverse impacts to individual organisms could occur but are not expected to be substantial
considering the mobile nature of fish. Temporary impacts are expected to come from the
temporary loss of benthic species for foraging. Due to the already disturbed nature of the site and
the quick recolonizing ability of benthic organisms, recovery should occur in the short-term. Any
changes in benthic community structure should be localized and, with respect to fisheries resourc-
es, have little effect on a baywide basis.
WETLAND RESOURCES
Since there are no regulated federal or state wetland resources associated with MBDS,
no impacts will occur.
No impacts are anticipated to the existing wildlife at MBDS.
THREATENED AND ENDANGERED SPECIES
Several endangered whale and turtle species can occur in the Massachusetts and Cape
Cod Bays. Endangered whale species have been observed within the two nautical mile circular
boundary of the MBDS. The impact of the use of the MBDS on endangered species is currently
being assessed by ACOE NED. Use of the site to date has not indicated any impact to threatened
or endangered species. Full coordination with the NMFS ensures compliance with the protection
of endangered species and their habitats.
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Massachusetts Bay Disposal Site (MBDS)
HISTORICAL AND ARCHEOLOGICAL RESOURCES
No impacts are anticipated, since no historical or archeological resources of record
exist at MBDS.
SOCIO-ECONOMIC/LAND USE
Since MBDS is an active dredge material site, no additional impacts are expected to
site usage or commerce than may presently exist.
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Boston Lightship Disposal Site (BLDS)
2.6.2
Boston Lightship Disposal Site (ELDS)
The site is depicted on Figure A1-21.
BLDS is a historic area for dumping of various materials (e.g., barrels). Therefore,
prior to any disposal of dredge materials at BLDS, surveys to determine where, if any, barrels
occur in the disposal site, and hydrographic surveys of the area, are needed to determine if the
site is stable. BLDS is an area for which previously collected sidescan sonar records are being
analyzed by the United States Geological Survey to map acoustic patterns and related sedimentary
environments (Butman et al. 1992).
2.6.2.1 Existing Conditions
SEDIMENT CHARACTERISTICS
Information collected under the DAMOS (1979a) program indicate that the heavy
metal content of the sediments collected from the disposal site were among the highest found in
the study between the two Massachusetts Bay Disposal sites. Even still, comparison of the
sediment chemistry results with the Massachusetts Dredged Material guidelines show that the
metal concentration would be classified as Class I (low).
WATER QUALITY AND CIRCULATION
i
Water quality and circulation conditions at BLDS are presumed to be similar to those
at MBDS. Both the MBDS and Boston Lightship are reported to have extremely weak tidal
current but could be subject to some wave motion (DAMOS, 1979a).
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Boston Lightship Disposal Site (BLDS)
AQUATIC RESOURCES
Benthic Infauna
A summary of the benthic species collected at BLDS in December of 1977 and May
of 1978 indicate a smaller number of individuals and species than at other disposal sites located
in the Gulf of Maine (DAMOS 1979b). Dominant benthic species include the polychaetes
Sternapsis scutata, Nepthys incisa, Maldane sarsi, Lumbrinerisfragilis, Ninoe nigrippes, Goniada
maculata, Ampharete acutifronons, nemertean worm Micrura sp., burrowing anemone Edwardsia
elegans, and the amphipod Hippomedon serratus (DAMOS 1979a).
Mussels (Modiol-us modiolus) were deployed at BLDS in 1978 to monitor temporal
and spatial variations in ambient metal and other chemical concentrations in the sediments
(DAMOS 1979b). Results indicated that the mussels at BLDS had metal concentrations which
approximated those in animals at Halfway Rock, a reference site. Data indicates that the reference
population at Halfway Rock, being closer to terrestrial sources of contamination, is probably
exposed to similar or higher concentrations of some trace metals than the mussels held at the
disposal site (DAMOS 1979b). However, subsequent samples taken from both the reference and
disposal site showed increases of the disposal site concentrations over those of the reference
station.
Sediment profile camera sampling at the Boston Lightship revealed a healthy benthic
community. Nearly three-quarters of the areas sampled had predominantly fine sand substrate
over silt (indicating a depositional environment), with a few areas that were solely sand or silt clay
(NAI and Diaz 1995). The depth to the RPD layer was at least 1 cm, indicating sediments were
well oxygenated. The sediment surface was diverse, and contained topographic features such as
pits, mounds, bedforms, and clasts. Worm tubes were observed on the sediment surface; burrows
were occasionally observed at depth. Total abundance of the benthic community was 9,066/m2,
moderately high among the offshore stations (Habitat VJQL, Table Al-10). The 125 taxa collected
in the 8 samples were mainly opportunistic, surface-dwelling polychaetes. The most abundant
species, Spio limicola, represented 47% of the total abundance. Secondary dominants included
Mediomastus californiensis (7% of the total abundance) and Prionospio steenstrupi (6%). The
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Boston Lightship Disposal Site (BLDS)
benthic community at Boston Lightship could be considered to be at a successional stage beyond
pioneering but not yet at equilibrium. Monitoring in August 1994 (SAIC 1994) noted a somewhat
healthier benthic community, as indicated by deep-dwelling benthic fauna such as holothuroids,
which were not collected in the October survey. The remaining stations mainly had fine sand
sediments overlying silt with pit and mound topography. The depth of the RPD layer was 1.5-2.5
cm below the sediment surface. Other characteristics were consistent with the majority of the
stations. The benthic community had one of the lowest total abundances (4732.7/m2) of all Outer
Harbor stations (Habitat VUL, Table Al-10). A total of 76 taxa were collected in the 3 0.04-m2
samples. Spio limicola was the most abundant species, representing 21% of the total abundance.
infish
The Massachusetts Bay area is a productive fishery habitat. Fish reported to occur
in the area of the disposal site include cod, dab and gray sole, yellowtail flounder, whiting, and
Atlantic herring; all are caught near the vicinity of the Boston Lightship and the MBDS (DAMOS
1979a). Lobster and ocean quahogs are also reported in the area.
WETLAND RESOTJRCES
There are no protectable wetland resources subject to federal or state jurisdiction at
BLDS.
WILDLIFE
Wildlife, including great cormorant (P. carbd), herring gull (L. argentatus), white
winged scoter (M. deglandi), common goldeneye (B. clanguld), bufflehead (B. albeold), mallard
(A. platyrhynchos), black duck (A. Rubripes), merganser (Mergus spp.) and scaup (Aythya spp.)
are likely to intermittently utilize BLDS for feeding and resting. Each of these species feed on
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Boston Lightship Disposal Site (BLDS)
fish and invertebrates (Martin et'al. 1951; Whitlatch 19182; DeGraaf and Rudis 1986) that occur
in the area.
THREATENED AND ENDANGEI
BLDS is located in Massachusetts Bay, an area known to be utilized by various
marine mammals, but outside the boundaries of the Stellwagen Bank National Marine Sanctuary.
Cetaceans are transients of the disposal site, but are not likely to be impacted by ocean disposal.
Endangered whale species are known to congregate above the shallow (30 meter) Stellwagen Bank
(U.R.I. 1981) when foraging for prey (e.g., sand lance Ammontytes americanus). Endangered
species presumed to be transients at BLDS include the finback whale Balaenoptera physalus; the
sei whale Balaenoptera borealis; the humpback whale Megaptera novaeangliae and possibly the
northern right whale Eubalaena glacialis (MBO 1987). Threatened or endangered turtles could
transit this area as well. The impact of the use of Boston Lightship on endangered species is
currently being assessed by ACOE NED. Boston Lightship is further removed from the prime
threatened and endangered species habitat at Stellwagen Bank. Use of the site to date has not
indicated any impact to threatened or endangered species. Full coordination with the NMFS
ensures compliance with the protection of endangered species and their habitats.
HISTORICAL AND ARCHEOLOGICAL RESOURCES
BLDS has historically been used for disposal of dredged material. No historical or
archeological resources are expected to occur at the site.
SOCIO-ECONOMIC/LAND USE
Extensive shipping, fishing, recreational activities, and scientific investigations take
place in Massachusetts Bay year round. There are no known interferences from disposal events
on these activities (EPA ROD 1993). In addition, the availability of the BLDS for the vast
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Boston Lightship Disposal Site (BLDS)
majority of sediments from Boston Harbor provides a potential solution for the disposal of large
amounts of dredged material.
2.6.2.2 Environmental Consequences
Boston Lightship (BLS) is the only previously-used dredged material disposal site
being considered for the disposal of silts from the BHNIP. In addition to disposal of three million
cubic yards of dredged materials from Boston Harbor through the 1970s, waste containers
containing hazardous and low level radioactive materials, as well as construction debris and
sunken vessels, have been dumped at this site. The EPA has conducted, and plans to continue
to conduct, investigations on the nature and condition of the chemicals disposed at BLS. The
EPA has expressed reservations about the use of this site for disposal of dredged materials until
their investigations have been concluded and evaluated. The following analysis is based on the
assumption that the conclusion of the EPA's studies will indicate that the material previously
dumped at the site would pose no hindrances to future use for disposal of dredged materials. That
is, the question of restrictions caused by the existing barrels will be deferred until the evaluation
of practicability criteria. The discussion in this section will focus on the suitability of the natural
physical and biological environment to support the proposed activity.
The site would require no preparation other than placing a buoy to mark the disposal
location. Dredged material (silt) would be disposed from barges directly onto the unmodified
substrate. The silt would be capped with parent material.
Direct Impacts
Because this site is in a depositional environment (Knebel 1993), it is expected that
the disposed dredged material would settle onto the substrate in a mound. SAIC (1994) identified
deposits of dredged materials dating back to at least the 1970s. The benthic resources in the
footprint of the mound would be smothered. The existing character of the substrate is
I
predominantly hard sand colonized by a diverse benthic infaunal community. Disposal of silts
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Boston Lightship Disposal Site (BLDS)
and capping with clay would alter this substrate in a way that, without modification (through
biological activity or physical forces), would not be attractive to recruitment of benthic fauna
immediately. It could eventually recover to support the same benthic infaunal community that
exists now. SAIC (1994) identified extensive recolonization of old dredged material with late
successional stage organisms.
Indirect Impacts - Short-term Water Quality Effects
Because Boston Lightship is located outside of state waters, use of the federal
definition of the mixing zone (compliance with acute water quality criteria outside the boundary
of the mixing zone within four hours of each disposal event) is appropriate for this site. For
designated open water disposal sites, under Section 103, the established site boundaries mark the
edge of the mixing zone. Sediment disposal simulations for the Boston Lightship site conducted
with COE's ADDAM'S model showed that four hours after a 2,000 cy disposal event water
quality criteria for copper were not exceeded outside the disposal site's boundaries (Table Al-19).
Since this was true for the summer (stratified) condition, it would be safe to assume it would hold
for winter (unstratified) conditions as well. Within the site, soluble copper concentrations in the
water column were also estimated to be below the chronic water quality criterion. After a four
hour period, the total volume of silt within the cloud was estimated to be equivalent to about 3.3%
of the initial disposal volume. These results indicate that risks to marine resources would be
minimal since water quality criteria would be met after two hours within the disposal site.
Indirect Impacts - Long-Term Water Quality/Site Stability
The typical bottom currents at Boston Lightship are about 0.5 ft/sec (15 cm/sec).
These currents are sufficient to keep silt in suspension, although too low to erode consolidated silt.
The extent of the hard sand substrate (>70% of the stations examined by Sediment Profile
Imagery) at Boston Lightship is indicative of the regularity of this current regime. The water
depths (about 50 m) and its location outside of normal shipping lanes make it unlikely that the
substrate at Boston Lightship would be affected by vessel traffic.
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Boston Lightship Disposal Site (ELDS)
The Boston Lightship area faces an unlimited fetch from winds from all directions
except west The water depth is again beneficial in protecting this site from the wind-wave
generated bottom currents. A one-year return storm event is estimated to produce nearbottom
currents of 1.6 ft/sec (49 cm/sec), more than sufficient to erode unconsolidated silt or consolidated
silt with little clay. Because silts disposed at Boston Lightship would be mounded, they would
be more readily eroded than if placed in a depression.
Use of the Boston Lightship site would require interim capping in anticipation of wind
or storm events that could disturb the bottom.
Indirect Impacts - Downstream Resources
Biological sampling hi the fall of 1994 revealed the presence of a diverse benthic
community of moderate abundances. Lobster catches were relatively high (lower than the
Meisburger sites, but substantially higher than any Boston Harbor locations). Trawl samples
(Table Al-4) were dominated by lobsters (59% of the catch) and winter flounder (28% of the
catch). Total catch was similar to that in Boston Harbor, although the relative abundance of
lobsters was higher in the offshore catch.
The COE estimates that disposal of silt at Boston Lightship would result in the
dispersion of about 5% of the material from the site through water column transport. The water
depths indicate that it would take less than 5 hours (less than 0.5 tidal cycles) under nonstratified
conditions for this vagrant silt to reach the substrate. The area where vagrant silt from an
individual disposal event reached the bottom would vary with the tidal stage, but over the course
of the project, the silt could be deposited in a concentric circle around the point of disposal. The
unconsolidated nature of the silt would make it highly susceptible to resuspension, therefore, it
is unlikely that it would be detectable in future monitoring.
It is this area of silt deposition, however, that could be identified as the downstream
area of concern. The benthic community observed in the fall of 1994 was composed of a mixture
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Boston Lightship Disposal Site (BLDS)
of surface and burrowing species. The surface-dwelling species and sessile suspension and surface
deposit-feeders would be more susceptible to the effects of smothering than the burrowing species.
Indirect Impacts - Biological Exposure Potential
Water Column Effects
The depth at which Boston Lightship is located provides a large volume of water to
dilute dissolved contaminants and suspended sediments following each disposal event. No
constituents are expected to reach concentrations in the water column that exceed the chronic
water quality criteria. Therefore, the potential for pelagic organisms to be affected by disposal
activities is negligible.
Substrate Effects
While the Boston Lightship area has been used for disposal of dredged material and
other material in the past, the extent of contamination in the substrate is not well defined.
Because all areas examined in fall 1994 were characterized by granular (sandy) or rocky substrate,
it is unlikely that contaminants are widespread, although there may be localized pockets in the
vicinity of earlier disposal activities. Creation of a mound of silly material from Boston Harbor
would create an approximately 100-acre area of elevated concentrations of organic and inorganic
contaminants until it was capped. The frequent disposal activity in the area from the BHNIP
would continuously disturb the site, likely preventing colonization by any but the most
opportunistic species. Absence of food and frequency of disturbance would tend to deter bottom-
feeding fish from lingering on the contaminated sediments.
Should sediments accumulate adjacent to the mound, there would be a greater risk of
exposure to demersal finfish. Because accumulation could occur without smothering the benthic
organisms, food would continue to be available for bottom-feeders. The potential for ingestion
and dermal contact would be higher than on the disposal mound itself. However, the ephemeral
nature of this siltation would counteract this potential.
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Boston Lightship Disposal Site (BLDS)
Other Issues
Cetaceans may transient the disposal site, but are not likely to be to impacted by ocean
disposal. This area is about 9 nautical miles west of the Stellwagen Bank; and thus sufficiently
removed from their main area for feeding and congregating so that problems from disposal activi-
ties should not occur. Disposal of dredged material at BLDS is not expected to have any
substantial adverse impact on endangered species, their prey, or the habitat essential for their
survival. Consultation with the NMFS under Section 7 of the Endangered Species Act of 1973
(as amended, 16 U.S.C. 1531 et seg),-bas been initiated to ensure this activity will not jeopardize
any endangered or threatened species.
BLDS is in an area deemed "sensitive" by the Board of Underwater Archeological
Resources because of the number of shipwrecks that have occurred there over time or because
historic disposal sites may contain material of archeological interest. However, discussion with
the staff of the Board suggests there may not be resources at the specific disposal site. This will
be confirmed by the staff upon review of the Board's files about the proposed sites.
BLDS is an inactive disposal site. Extensive shipping, fishing, recreational activities,
and scientific investigations take place in Massachusetts Bay year around. There are no known
or anticipated interferences from disposal events at this site except the uncertainty surrounding
conditions created by previous disposal of miscellaneous wastes. If these uncertainties can be
resolved, the use of the site could provide a solution for the disposal of large amounts of
unsuitable material by capping and sequestering the contaminants in the future.
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3.0 ENVIRONMENTAL EVALUATION-
DREDGING SITES
3.1
OTHER PROJECT CONSIDERATIONS
The majority of the environmental and socio-economic information concerning Boston
Harbor, and the areas to be dredged for the navigation improvement project, are discussed in
EIR/S Sections 2.0 and 4.0. Therefore, only additional information is covered here.
Besides the navigation improvement project, a 9.5 mile long sewage outfall tunnel is
currently being constructed from Deer Island underneath the seafloor into Massachusetts Bay for
the MWRA project Completion of the outfall pipe is expected in 1995. The Third Harbor
Tunnel will cross the main ship channel from South Boston to Logan Airport in East Boston.
Dredging for the tunnel was completed in 1993. Placement of the tunnel sections for the Third
Harbor Tunnel was completed in 1993. In addition, barge traffic will be hauling dredged and
excavated materials removed from the Central Artery to Spectacle Island.
Interference between construction of the above two projects and the associated
dredging of the navigation improvement project is not expected to occur. Construction of the
navigation improvement project is not expected to begin until 1996. No interference with the
MWRA project is expected. Barge traffic from this project is expected to be minimal. Potential
disposal site locations would not interfere with the construction of the outfall tunnel.
Deepening the Federal channels may involve relocating buried utilities. The
deepening in the Chelsea River was limited due to the expense involved with relocating the gas
siphon. Utilities that were identified include a powerline running generally down the center of
the Reserved Channel, telephone cable across the Inner Confluence, a water tunnel, electrical cable
and bridge cables across the lower Chelsea River and two water tunnels, a sewer siphon, a gas
siphon, electrical cable and fire alarm cable across the upper Chelsea River. Table A1-20 lists
the known utilities and expected depths.
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In most cases, the utilities will be relocated by burying them deeper under the channel.
The gas siphon is a special case and will have a protective layer of rip-rap placed over the line
rather than actually relocating the siphon.
The deepening of three harbor tributaries will require particular care to avoid damag-
ing utilities crossings. During November 1992 field data were collected using side scan sonar and
an array of geophysical instruments which enhanced existing knowledge of buried utilities. While
the information obtained does not precisely locate the depth of utilities, it does show either the
trench or changes in bottom material densities indicating existence of trench excavation and fill.
This information has not been published yet, but some data are currently available.
The berthing areas and bulkheads adjacent to the navigation channels will be
investigated to ensure that dredging a deeper channel will not undermine the integrity of the
bulkheads. Surveys conducted to date have not revealed evidence of this type of problem.
3.2 DREDGING AREAS - ENVIRONMENTAL RESOURCES
3.2.1 Water Quality
The dominant currents in the harbor are tidal in origin, although wind driven currents
occur during storms. Freshwater discharges from the Mystic, Charles, and Chelsea Rivers gener-
ally overlie the more dense seawater flows from the tides. Freshwater flows average 350 to 500
cubic feet per second (CFS) in the summer. Tidal input is several orders of magnitude greater
than freshwater input. Tidal flows average 320,000 cubic foot per second (CFS) for a six hour
period with volumes ranging from 10.6 billion gallons at low tide to 179.9 billion gallons at high
tide (Metcalf and Eddy, 1976, and MDWPC, 1986). Approximately 73.3 billion gallons are
exchanged through three channels linked with the President Roads area and one channel linked
with Nantasket Roads. In addition, 265 million gallons per day of waste water is released into
the Harbor system from the Boston regional wastewater treatment plant on Deer Island.
The average tidal range in Boston Harbor is 9.5 feet with spring tidal ranges often in
excess of 11 feet. Average current velocities for the Inner Harbor are less than 0.5 knots. Tidal
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currents in other portions of the Harbor Vary greatly in speed because of the irregular bottom
topography and the large number of islands (Knebel, etal., 1991). In general, maximum near-
bottom current speeds are greatest (> 10 knots) in constricted channels and depressions, are
intermediate (3-6 knots) at locations sheltered by islands and points of land, and are weakest (<
3 knots) over the shallow subtidal flats (Bumpus, etal., 1951; U.S. Coast and Geodetic Survey,
1953; Mencher, et al, 1968; National Ocean Survey, 1977; Signell and Butman, 1990 in Knebel,
etal., 1991). Maximum current .velocities during spring tide in the areas to be dredged are as
follows: 0.1 knots in the Mystic River, 0.2 knots in the Chelsea Rivers and 0.7 knots in the Main
Ship Channel vicinity (N.O.A.A., 1986).
The quality of water in Boston Harbor has been the target of considerable expenditures
of Federal, State and private funds. For the most part, raw sewage and untreated industrial
discharges are being rectified by the Massachusetts Water Resources Authority (MWRA) under
a court order aimed at cleaning-up Boston Harbor. A new primary sewage treatment plant is
currently under construction on Deer Island, including relocation of the ocean outfall from the
island to nine miles offshore. The construction of the first battery of secondary treatment
upgrades is to begin shortly. Disposal of sewage sludge into Boston Harbor ceased in 1992. This
has resulted in a rapid and measurable increase in water quality (MWRA, 1993). Water quality
is expected to improve further when the secondary treatment facility on Deer Island is in full
operation in the year 2000 (MWRA, 1993). The history of contamination from these and other
sources in Boston Harbor can be found in the harbor sediments.
Water quality in Boston Harbor has been found to vary both spatially and temporally.
The Feasibility Study provided a general seasonal summary of previously available data. A more
recent data set for June through October 1985 (MDWPC, 1986 and New England Aquarium,
1990) is also within the ranges listed on this summary.
Barring localized effects around thermal outfalls from power generating stations, the
temperature regime in the Harbor is under normal climatic and estuarine controls. The enrichment
level in the outer harbor is generally considered to be at a mesotrophic scale without excessive
primary production (National Commission on Water Quality, 1976). The inner harbor is also
enriched from combined sewer outflows and the high level of nutrients in the river system feeding
the harbor.
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Vertically averaged dissolved oxygen levels (MDWPC, 1986) exhibit values ranging
as low as 4.5 ppm in the project area. These values represent summer biological activity in con-
junction with organic enrichment of the ecosystem. Oxygen depletion is a substantial problem
in many estuaries during times of thermal stratification of the water column. The strengthening
and deepening of the water column thermocline limits the circulation and oxygen exchange in the
nearbottom waters. As temperatures peak (often in August), available dissolved oxygen levels
decrease and cause a corresponding depression in biological activity at the sediment water
interface. This "August Effect", as it is commonly referenced, is a major environmental factor
in structuring biological communities in the project area.
The Massachusetts Water Resources Authority (MWRA) and the New England
Aquarium have measured dissolved oxygen throughout Boston Harbor. MWRA (1992)
measurements of bottom waters in the Inner Harbor frequently show DO below the standard 5.0
mg/1, with occasional measurements below 2 mg/1. Low oxygen conditions are much rarer in
surface waters, and tend to occur in restricted channels with high combined sewer overflows
(CSO) input, such as Fort Point Channel and the Reserved Channel (MWRA, 1992). Dissolved
oxygen in the Outer Harbor and Dorchester Bay measured by MWRA and the Aquarium moni-
toring programs are nearly always above the 5 mg/1 standard for Class SB waters. The water
chemistry of the project area, in particular the organic load and its subsequent chemical oxygen
demand, is a substantial factor in the ecology of Boston Harbor.
Salinity data indicate the Outer Harbor is well mixed, while the various regions of the
inner harbor are under the influence of freshwater inputs. Essentially, the mouth of the Harbor
is considered stenohaline and the Inner and Outer Harbor areas are euryhaline. Oil pollution has
created problems in many harbor areas and a permanent oil boom is maintained at the mouth of
Chelsea Creek to protect the remainder of the Harbor from potential spills in the main tanker
terminal areas.
Coliform bacteria counts have been collected by several agencies for several decades.
Bacterial counts have decreased 10 to 100-fold over the past 50 years in the Inner Harbor, near
Deer Island, Nut Island, Governors Island, President Roads, Nantasket Roads, Moon Head, and
Dorchester Bay (MWRA, 1992). These improvements are related to the construction of treatment
plants. Bacterial counts in the Inner Harbor were lower in the 1980s compared to the 1960s. The
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extreme violations of fecal coliform water quality measured near Deer Island by the New England
Aquarium have not been found since 1988, and water quality near Nut Island has been good since
1987. This improvement in offshore bacterial water quality has been associated with more reliable
chlorination of the wastewater treatment plants (MWRA, 1992).
Water quality in the Outer Harbor varies greatly. In 1989 and 1990, MWRA sampling
showed that Carson Beach, Pleasure Bay and Northern Dorchester Bay generally met water quality
standards. Samples taken near Calf Island in the outer harbor were all within swimming
standards. Southern Dorchester Bay, at the mouth of the Neponset River, generally showed poorer
water quality. This area is affected by the Neponset River, storm drains outflow, CSOs and
possibly sludge. Samples collected at Dorchester Bay beaches in 1991 by MDC indicate a
decrease in the number of postings at the two beaches in Southern Dorchester Bay: Tenaean and
Malibu. The decrease in postings at these areas can probably be attributed to the operation of new
disinfection facilities at Fox Point and Commercial Point sewer outfalls.
In Boston Harbor productive clam beds cover about 4,700 acres (Figure Al-22)
(MWRA 1992). None of these beds are open for recreational clamming because sewage indicator
bacteria counts are too high (MWRA, 1992). About 2,900 acres of clam beds are restricted to
harvesting only by "Master Diggers". These licensed diggers must take all clams harvested to
a depuration facility, where the shellfish are held in clean water for two days to cleanse
themselves of bacteria.
The Massachusetts Division of Marine Fisheries monitors shellfish growing water as
well as the clams themselves for bacteriological safety. Some areas of Boston Harbor, especially
in Quincy Bay and Hingham Bay, are often conditionally opened, while other areas, like
Dorchester Bay, are virtually never open (MWRA, 1992). Clam beds in the Inner Harbor are
prohibited from harvest.
Levels of trace metals in the inner harbor have been related to the sewage discharges,
CSOs, urban runoff, and the metals contributed by the major rivers. In the Outer Harbor, higher
levels of metals have been found around the sewage outfalls. The U.S. Environmental Protection
Agency has developed water quality criteria designed to protect aquatic organisms from the
adverse effects of environmental contaminants. Boston Harbor generally meets the water quality
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criteria for toxic contaminants (MWRA, 1992). There has been a four-fold decrease in the
amount of metals discharged to the Harbor by the MWRA between 1981 and 1991. Results of
bioaccumulation studies conducted by MWRA (1992) in 1991 and other studies indicate or
suggest that improvements in MWRA discharges are being reflected in improvements in water
quality. Although the quality of discharge from MWRA treatment plants is improving, and is
expected to improve, various levels and types of contaminants are still released into the aquatic
system. These discharges combined with riverine and direct urban runoff represent a degradation
of the Boston Harbor water quality.
3.2.2
Sediment Characteristics
General Site Environment
The United States Geological Survey (USGS) currently is conducting studies in
Boston Harbor, Massachusetts Bay and Cape Cod Bay to define the geological framework of the
region and to understand the transport and accumulation of sediments (Butman, etal., 1992). One
of the goals of the USGS study is to develop a sediment data base. The levels of contaminants
vary throughout the Harbor predominantly depending on hydrology and substrate type. In general,
metal and organic levels are relatively high in the Inner Harbor and decrease seaward. The
surficial sediments represent fine grained material with associated chemicals deposited since the
area was last maintained. The results of the chemical sampling reflect the normal sedimentologi-
cal trends of increased chemical levels with those substrates of higher total organic carbon and
silt-clay content (Boehm et al. 1984). The Mystic River (sampling stations A and B) exhibited
the highest contaminant levels and was also the most recently dredged. The material accumulated
at these stations represents the highest levels in the harbor, apparently derived from the Mystic
River drainage area. In contrast, the least contaminated material in the harbor is also found in the
Mystic River at Station C. This station is typical of the pristine lean clay layer of the deeper
sediments without deposition of a recent silt/clay overburden.
An acoustic impedance survey of the Federal channels to be dredged was performed
by ACOE in November 1992. This survey was conducted to locate and determine the amount of
silt (maintenance layer), clay, and rock. This survey was also used to assist in locating utilities.
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The surface sediments in the federal channels and the berth areas are subject to
resuspension during virtually every ship passage. Appendix G presents an estimate of the bottom
velocities that are generated by the various types of cargo vessels and tugs that operate in Boston
Harbor. Silt, the predominant grain-size of the surface sediments, can be resuspended by currents
as slow as 0.2 m/s. Bottom velocities generated by cargo vessels passing at slow speeds through
the harbor (according to the traffic patterns described in the Shiphandling Simulation Study
provided in the DEIR/S) can exceed this value up to 400 m astern of the vessel. Tugs can
generate bottom velocities above this value up to 200 m astern. These velocities dissipate rapidly
as the vessels traverse the channel. Sediments resuspended by these currents settle back to the
substrate after being transported relatively short distances. Turning areas are particularly
susceptible to this influence. Portions of the confluence of the Mystic River, Chelsea River and
Main Ship Channel showed evidence of scour in the acoustic impedance study; parent material
is exposed in these areas.
Upland Disposal Testing
The Massachusetts Department of Environmental Protection requires information on
additional parameters (total petroleum hydrocarbons) and toxic characteristic leaching procedure
(TCLP) in order to evaluate the suitability of dredged material for upland disposal. Chemical
testing was also performed for sodium and chlorides at the request of the interagency work group
members and because both sodium and chloride can have an impact on ground water if the
sediment is disposed of upland and leaching occurs (at unlined sites).
The averages for total petroleum hydrocarbon (TPH) concentrations and Total Organic
Carbon (TOC) for all sites tested are presented in Table Al-21. The highest average concentra-
tions of TPH was found at the Mystic Pier 1 site and the lowest average concentration of TPH
was found at the Conley 11-13 site. The highest average concentration of TOC occurred at
Edison Barge Intake and Edison Barge Berth (13.0% and 10.2% respectively) and the lowest
average concentration of TOC occurred at the Gulf Oil site (1.7%).
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Toxic Characteristic Leaching Procedure (TCLP)
If the bulk chemical concentration in the sediment tested equaled or exceeded the
Massachusetts Department of Environment bulk soil concentration for TCLP analysis, then there
. is a mathematical chance that the TCLP test could exceed threshold limits. In order to know if
the parameter of interest would exceed the EPA regulatory limit, a TCLP test must be performed
in order to verify if the sediment has hazardous characteristics. Only chromium and lead
exceeded the mathematical thresholds for requiring TCLP analysis. Table Al-22 is a summary of
the MassachusettsDEP Bulk Soil Concentration limits along with the lead and chromium bulk and
TCLP concentrations in relation to the regulatory limits. In all cases the TCLP results were orders
of magnitude below the regulatory levels. Therefore, none of the sediments to be dredged in
Boston Harbor show hazardous characteristics.
Table Al-23 shows the concentration of sodium and chloride found at each site tested.
The highest concentration of sodium occurred at Eastern Minerals (40140 mg/kg) and the Mystic
Piers had the highest percent of chloride (2.0%).
3.2.3
Biological Resources
In July and November 1986 benthic biological sampling was conducted at thirteen
(13) stations in the proposed dredging area. Finfish samples and water column parameters were
also obtained at various locations. In general, the benthic population in Boston Harbor is
described below, based on results from thirteen (13) stations randomly located throughout the
project area and sampled in two seasons. The sampling program used a 0.04m Van Veen grab
and screened samples through a 0.5mm sieve. Additional details can be found in the 1988
Environmental Assessment
All three tributaries of the Boston Harbor navigation improvement project contained
on average a high number of organisms per square meter (4,798; S.D. = 8623.2) in July. The
average number of species recovered in July was eight (S.D. = 8.4). The dominant organisms
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were the polychaetes Capitetta capitata (54.8 %, S.D. = 28.3); Polydora ligni (15.3%, S.D. =
7.1); and Polydora aggregata (12.3%, S.D. = 11.7).
The Inner Harbor rivers and the Reserved Channel undergo remarkable reductions in
densities between seasons. Theoretically, a population can rebound from nearly an azoic state
(induced by low dissolved oxygen levels) through adult recruitment. Between July and
November, a statistically significant (p < 0.005) reduction in benthic population densities and
diversity occurred. The November population contained on average a much lower number (29;
S.D. = 71.5) of organisms per square meter and number of species (0.4; S.D. = 0.7). The
dominant organisms were the polychaetes Polydora ligni (20.0%; S.D. = 11.5); Streblospio
benedicti (17.9%, S.D. = 16.8); the sand shrimp Crangon septemspinosa (11.0%, S.D. = 19.0);
and the amphipod crustacean Ampelisca abdita (6,7%, S.D. = 11.5).
This tremendous reduction in benthic productivity is not uncommon in urban estuaries
where the cumulative effects of high organic load, vessel wakes, increasing water temperature,
reduced wind mixing, and increased water column stratification combine with microbial activities
that peak in late summer to reduce dissolved oxygen levels. The dissolved oxygen stress is often
severe enough to eliminate non-motile benthic populations — the so-called "August effect".
Given the cyclic (annual) nature of low dissolved oxygen levels in Boston Harbor, the
benthic inhabitants are well adjusted to colonizing and recolonizing azoic substrates annually.
This type of pioneering species assemblage can be expected quickly to recolonize a dredged area
with minimal disruption in benthic productivity.
The polychaetes Capitella capitata and Streblospio benedicti are the dominant benthic
organisms present in the project area. Both of these species are tolerant of physical and chemical
stresses that are characteristic of urban harbors such as Boston. Each of these species are "r -
strategists," i.e. species whose life history is characterized by small body size, short generation
times and high reproduction (r) rate (Grassle and Grassle, 1984). Capitella capitata has shown
generation times as short as three weeks (Tenore and Chesney, 1985). These life history attributes
allow the proliferation of this species within the project area on a cyclic basis. High densities of
Capitella capitata were found in July but not in November. This cycle of proliferation and die-
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off keeps the benthic population in a state of dynamic equilibrium. Project areas which were
azoic in both sampling periods may have a sufficient additional stress of sulphidic or petroleum
compounds accumulating in the substrate so that it is intolerable to even these species (James and
Gibson, 1980). This cycle of recolonization by the benthos can be expected to allow rapid
biogenic reworking and recolonization of the newly exposed clay layers in the post dredging
phase.
The soft shelled clam Mya arenaria is the most common commercial shellfish within
the Boston Harbor area (Figure Al-22). Blue mussels Mytilus edulis and duck clams Macoma
balthica are also found in shellfish beds but are not harvested. Densities of shellfish beds have
been documented by Jerome et al. (1966), Chesmore et al, (1971) and Iwanowicz et al. (1973)
and these data can be referred to for detailed information.
As described in the previous section, waters overlying the shellfish beds are con-
taminated by wastes from sewage outfalls, resulting in the presence of coliform bacteria in the
shellfish. The beds are under the jurisdiction of Massachusetts Department of Environmental
Protection and are closed to commercial and noncommercial harvesting, except by Master Diggers
who must have the clams depurated at a purification plant.
Most of the productive soft shelled clam beds near the proposed dredging project are
closed except for restricted areas near Logan Airport and a seasonal area in Pleasure Bay, the
latter located immediately southwest of Castle Island. Logan Airport beds are one nautical mile
north of President Roads and the beds at Pleasure Island are about two nautical miles west of
President Roads. Shellfish beds open to Master Diggers are predominantly within the lower bays
and are distant from the shipping channels and project areas.
The limited amount of lobstering within the Boston area takes place primarily in
Quincy, Dorchester, and Hingham Bays. Lobstering is minimal or nonexistent in the areas to be
primarily affected by the proposed work.
Fisheries resources of the Inner and Outer Harbors have been inventoried by previous
studies. These studies include the-MES (1972, 1972 a, b, c; 1973; 1976 a, b; 1977 a, b) and
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Haedrich and Haedrich (1974) studies Which developed information in the Lower Mystic River.
Data in the Outer Harbor were developed by Jerome et al. (1966), Chesmore et al. (1971) and
Iwanowicz et al. (1973).
The studies on the lower Mystic River were concentrated in the area between Amelia
Earhart Dam and the Mystic River (Tobin) Bridge. Haedrich and Haedrich (1974) found that the
seasonal species composition was similar to other northeast harbor communities. Winter flounder,
smelt and alewives are found in the river throughout the year and are, therefore, considered
residents. Ocean pout and blueback herring are summer residents, whereas sea herring is
considered a winter resident. With the exception of ocean pout, these residents were identified
in the 1986 NED biological sampling effort.
In fall 1994 finfish were sampled in the Mystic River, Chelsea River and Inner
Confluence using an otter trawl. Results are presented in Table A1-4. Winter flounder was the
most abundant species collected in each area.
Finfish sampling identified anadromous finfish, resident finfish and lobster as
occurring in the project area. In a recent report by the National Oceanic and Atmospheric
Administration (N.OA.A. 1984), anadromous finfish species were identified as being of special
concern in the project area.
Information on spawning species, numbers and quality of spawn and their significance
to regional resources is imprecise and sketchy. Since the principal streams discharging into the
Inner Harbor rivers have dams located on them, tidal spawns of smelt and alewives are unlikely.
In addition, it is not known if winter flounder use Boston's Inner Harbor for spawning as well as
an area of local feeding. From the habits of these fish and from their behavior in the Mystic
River channel area, they appear to stay in particular resident areas within the Inner and Outer
harbors. Larval contribution to the eventual recruitment of these fish in other areas is not known.
In summary, a spring/summer movement of anadromous finfish occurs through the
project area as they move into spawning (freshwater) tributaries. Lobsters and flounder are
generally in the Outer Harbor (areas of high productivity) preferring cool waters. In summer, as
water temperatures rise, productivity in benthic habitats sharply decline hi response to low
Al-187
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. dissolved oxygen in the near bottom water column, restricting fauna to the Outer Harbor (Main
Ship Channel) areas. By fell, the Inner Harbor has juvenile flounder feeding on sand shrimp
while waters are cooling toward winter spawning temperatures. In winter, finfish, except for the
cold water spawning flounder, and lobster move offshore as harbor water temperatures decrease.
This fell/winter water cooling allows a balance of the oxygen depletion that occurred in the
warmer seasons. High organic load freshwater inputs and warming water temperatures initiate the
complex cycle in the spring.
Offshore and longshore areas of the Harbor were trawled for finfish in the studies
done by the Massachusetts Division of Marine Fisheries. Atlantic silverside, mummichog and
Atlantic tomcod were the predominant species found in the longshore trawls. Some of the
offshore sampling sites yielded high densities of winter flounder, Atlantic tomcod, fourspine
stickleback, and rainbow smelt The highest densities of finfish were taken during the months of
September and October, with Atlantic silverside and winter flounder the predominant species. The
densities of finfish dropped during the winter months of December through March as the fish
moved offshore to winter feeding grounds.
Al-188
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4.0
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Al-198
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Boston Harbor Dredging Project EIR/S
Scale:
0 10
Approx. Scale in Miles
Rguie A-l. Locations of short-listed sites.
Source:
USGS Quadrangles
Revised by NAI to reflect pertinent site conditions.
-------
SL- SHRUBLAND
WEM- EMERGENT WETLAND
Boston Harbor Dredging Project EIR/S
W
Scale:
0 100 200
Scale in Meters
Rgure Al-2. Site map for potential disposal site,
Quincy-03 (Squantum Point).
Source:
USGS Quadrangle Boston South, MA, 1987
Revised by NAI to Reflect Pertinent Site Conditions
-------
Park
&
Playground
Chariestown
Pumping
Station
Powerplant
UO- OPEN URBAN LAND
,„,, OF- EARLYSUCCESSIONALFIELD
l>AsSL- SHRUBLAND
{^Xfr.^V m.
Boston Harbor Dredging Project EIR/S
Scale:
100 200
Scale in Meters
fff-
Figure Al-3. Site map for potential disposal site,
Everett.
Source:
USGS Quadrangle North Boston, MA, 1985
Revised by NAI to Reflect Pertinent Site Conditions
4*1!
-------
Boston Harbor Dredging Project EIR/S
Figure Al-4. Site map for potential disposal site,
Wobum-11.
Scale:
Source:
100
200
SealtinMttm
USGS Quadrangle Reading, MA, 1987
Revised by NAI to reflect pertinent site conditions
-------
ZONE II AQUIFER
DEP WETLANDS
HARDWOOD FOREST
SHRUBLAND
EARLY SUCCESSIONAL FIELD
HARDWOOD FORESTED WETLAND
SHRUB WETLAND
OPEN WATER
ROCK OUTCROP
SAND & GRAVEL PIT
RESIDENTIAL
COMMERCIAL STRUCTURES
OBSERVED IN FIELD, SIZE
AND SHAPE UNKNOWN
Boston Harbor Dredging Project EIR/S
Scale:
100 200
ScaitatMtttn
Hgure Al-5. Site map for potential disposal site,
Wrentham-495.
Source:
USGS Quadrangle Franklin, MA 1987
Revised by NAI to reflect pertinent site conditions.
-------
7
Wrentnam \
State
Forest
PLAINVILLE
GP Sand and Gravel Pit
X Landfill Location
Boston Harbor Dredging Project EIR/S
Rguie Al-6. Site map for the Plainville
Landfill site.
Scale:
0 1000 2000
Scale in Feet
Source:
USGS Quadrangle Franklin, MA 1987
Revised by NAI to reflect pertinent site conditions.
-------
X - Landfill Location
Boston Harbor Dredging Project EIR/S
0 1000 2000
555ii5iSr
Scale in Feet
Hgure Al-7. Site map for the Fitchburg/
Westminster Landfill site.
Source:
USGS Quadrangle Ktehburg, MA 1988
Revised by NAI to reflect pertinent site conditions.
-------
WHITMAN
BROCKTON
E.BRIDGEWATER
RWGEWATER
X - Landfill Location
Boston Harbor Dredging Project EIR/S
fo
0 1000 2000
Scale in Feet
Figure Al-8. Site map for BFI Northern Disposal Inc.
(E. Bridgewater) Landfill site.
Source:
USGS Quadrangle Whitman, MA 1977
Revised by NAI to reflect pertinent site conditions.
-------
'f ' ' '\*V/'S,' 't"?Z •. "&"%<'• •S'-Xj.'?:
"'
f 5_ f ~ -f f f v v- f
s" ••* #3&nrtfe'' ''' ,''{', *',',<
•"* '"It's/ftf*./'A „/, ;?, SP»S^,, V's
^f^^»v V -'^v- ^ ~-
Boston Harbor Dredging Project EIR/S
Rgure Al-9. Site map for Mystic Piers site
Scale:
700
Source:
Boston Harbor Navigation Chan
-------
Boston Harbor Dredging Project EIR/S
(ft
S 0 50 100
Scale in Yards
Figure Al-10. Site map for Revere Sugar site
Source:
Boston Harbor Navigation Chart
-------
DISPOSAL SITE
Boston Harbor Dredging Project EIR/S
Figure Al-11. Site map for Amstar site
Scale:
Source:
Boston Harbor Navigation Chart
-------
Boston Harbor Dredging Project EIR/S
(B
Scale: ° 5f T
Scale in Yard;
Figure Al-12. Site map for Cabot Paint site.
Source:
Boston Harbor Navigation Chart
-------
Boston Harbor Dredging Project EIR/S
®
Sco/e:
0 100 200
ScaleinYardt
Hgure Al-13.Site map for Little Mystic Channel site.
Source:
Boston Harbor Navigation Chart
ft/-
-------
r
Site
• n Locus
• I I
LJL
Boston Harbor Dredging Project EIR/S
Scale:
0
100
._..se_ ..
Scale in yards
200
Figure Al-14. Site map for Reserved Channel site.
Source:
Boston Harbor Navigation Chart
L06
01-3119-
-------
', '~^<~-,.' ^"'/'" ' " '••' - , , "'-'", " - ' : - '"--sC^-x^f
'••- * "/' ^/^^^L ;"' ;-,""""" "''>",' . >-"~ ''-""x ' -'-' -V*': V: -*-\ /
'•< /, '" '^ ^ " ^^ ^Zr-' '/' ~ .^— ' -^"' '• ' "*"• »''-]"*''•' "'-' ''-^':-- C -'''^l, t"^"^! »$;?"" "
,f ,,-~ *v'' '\ •••• -•••• ^^~V2, .?. .'._^~~^~-^>-^l'?3' ^ 77~~^*~>J —'•^-^T'-iss.f'*'^ ' \''
\^ % * X /r^SC^^^^ SPECTACLE '*-gr^«£
r ^ O^ , ^ *tjy~^ ^^% X7^^^ ISLANDCAD fe^^-^
Boston Harbor Dredging Project EIR/S
Scale in Yards
500
1000
Figure Al-15. Site map for Spectacle Island CAD site.
Source:
NOS Chan No. 13270
Sediment Classifications from Cortell 1990
'/4/-3J3
-------
EXPlAHATtOH
Bast Potential for sand/gravel
i 15? Cor« Location
2518
2519
•95-
Narigotion Ft its
Contours ia F««t
Boston Harbor Dredging Project EIR/S
®
Scale ia TardJ
500 0 1000
Rgure Al-16. Site map for Meisburger 2 site.
Source:
Metcalf &. Eddy Inc., 1992
-------
Boston Harbor Dredging Project EIR/S
®
Sftfile*
Seal* IA Tare*
* i«5 2OOO
Hgure Al-17. Site map for Meisburger 7 site.
t i * GENERAL AREA WITHIN WHICH DISPOSAL
SITE WOULD BE LOCATED.
Source:
Meiealf & Eddy Inc., 1992
-------
r
s*a*&L3&&Ja££&L'~X~'*<
V^'M*'"^'" y%7-> '-7? •* '--
ST- K; -~ -v. ' &w*,v-,- "5"-^s; *
Boston Harbor Dredging Project EIR/S
®
0 10CO 2OOO
Scale in Feet
fl
Figure Al-18. Site map for potential disposal site,
Subaqueous-B
Source:
Boston Inner Harbor Navigation Chart
**-&
-------
Boston Harbor Dredging Project EIR/S
Scale:
400 SOO
Scale in Yards
Figure Al-19. Site map for potential disposal site,
Subaqueous-E.
Source:
Boston Inner Harbor Navigation Chart
fthJLll
h\\
-------
WINTHROP
HARBOR
Boston Harbor Dredging Project EIR/S
Scale:
400 SOO
Scale in Yards
Figure Al-20. Site map for potential disposal site,
Winthrop Harbor.
Source:
Boston Inner Harbor Navigation Chart
-------
130
8
§
I
o
ffi
I
a
w
a
3
>
i—i
^
s
MASSACHUSETTS
BAY DISPOSAL SITE
BOSTON LIGHTSHIP
DISPOSAL AREA
(HISTORIC)
Depositional substrates within the disposal sites.
' BLDS approximate proposed disposal location ~ 42° 19' 48" N
70° 37' 30" W
Al
-------
Figure Al-22. Prohibited and restricted clam beds in Boston Harbor. There are many acres
of soft-shell clam beds in Boston Harbor, but none are open for unrestricted harvest.
(From MWRA "State of Boston Harbor:1991" report)
-------
TABLE Al-1. LANDFILL CHARACTERISTICS
DAILY CAPACITY
Total Waste
Capacity
Available Waste
Capacity1
Cover Capacity
Available Cover
Capacity
ANNUAL TOTAL CAPACITY
STOCKPILING CAPACITY2
PLAINVILLE
850-925 cy/day
150-200 cy/day
500 cy/day
100 cy/day
350,000 cy/yr
FITCHBURG/
WESTMINISTER
350 cy/day
200 cy/day
250 cy/day
Unknown
100,000 cy/yr
200,000 cy
E. BRIDGEWATER
1075 cy/day
75 cy/day
400 cy/day
Variable
250,000 cy/yr
8,000-10,000 cy
WASTE MATERIAL LIMITATIONS
Dewatering
Solids
Odor
No free standing water
£40% solids
Deodorizing suggested
COVER MATERIAL LIMITATIONS Must meet DEP standards for
TCLP3, pH, solids, reactivity,
ignitability.
No free standing water
£25% solids
Must have no odor
Must meet 310 CMR 19
regulations.
ESTIMATED CLOSURE DATE
TOWN/BOARD OF HEALTH
REQUIREMENTS
1995, but proposed expansions 1997
would extend until 2000.
Verbal coordination needed
Coordination with 2 local
boards
No free standing water
£20% solids
If odor, BFI will lime
Must meet DEP standards for TCLP,
PCBs, reactivity, corrosivity, free
liquid, solids. Odor must be inoffen-
sive to community. No large boul-
ders.
1996
Coordination needed
(Continued)
-------
TABLE AM. (CONTINUED),
PLAINVILLE
FITCHBURG/
WESTMINISTER
E. BRIDGEWATER
9-
SPECIAL WASTE RECEIVED IN
PAST
Waste water treatment plant
grit and screenings
Wastewater treatment plant Sewage sludge, petroleum contami-
sludge. nated soil.
TRUCKING LIMITATIONS
Number/day
Operating hours
TIPPING FEE4
DISTANCE TO SITE
No limitations
7 AM - 3 PM
$56/cy
35 mi. .
No limitations
7 AM - 3 PM
$70/cy
45 mi.
No limitations
7 AM - 3 PM
$28/cy
25 mi.
'Capacity available for project dredged material.
2Unlined cover material can be stockpiled.
3Toxic Characteristic Leaching Procedure. An EPA-derived test for hazardous characteristics.
4Approximate costs assuming an average ratio of 1.4 tons/cy; actual tipping fees are based on weight.
-------
TABLE Al-2. ESTIMATED ABUNDANCE (NO./m2) OF BENTHICINFAUNA (RETAINED ON A 0.5 mm MESH SIEVE) COLLECTED BY
0.023 n,2 PONAR GRAB FROM PROPOSED DISPOSAL SITES IN BOSTON HARBOR, APRIL 28-2^1993
"^
•
)o
W
TAXA MP-J MP-2
Oliyochacta 43 g|7
Auitelliilos oculala
Cupllella cupilala 4)71
IJiiuyx uculos
Cirralulidae
Ctaenhks hyperbola
Duilacmeriu sp. 43
Kltone sp.
K. heleropoita
E. lunga
h'abricia sabella 172
Polynoidae
Laglsca txlenuala
Hesionidae
Luiloxcoloplos robustus
Mkniplilhalinus
abernnis
Neccidae
Heiliste diversiculor
Oibiniidae
Paranultes kosierlensts
Pholoe nilimla
folftirna sp.
Potyitora sp.
P. aggregulti 258
/'. CO/HUM 86
Pygosplo tlegitiis
STATION
HS-I RS-2 RS-3 AM-1 AM-2 CP-I CP-2 I.MC-J LMC-2 LMC-3 LMC-4 RC-1 RC-2 RC-3 RO4
473 '72 '" 559 l806 8« 13717 258 86 2451 15480 26574
43
2838 2967 2I5 . '« «« 645 ,677.
688 43 86 387 43
258
43 43
86
86
129 43 2|J
172
43
43
43
86 172
473 ' 2.5
/is )29
« 172
43 .72
258 215 43
43
172
43
731
43 43 2107 30. 86 559 2.5 MI9 4J ,„
(Continued)
-------
tr-
TABLE Al-2. (CONTINUED)
TAXA MP-I MM RS-1 RS-1
Xplo cf. llaileulii
.1. ittulin!
Spiuptmntsbmby*
STATION
RS-3 AM-1 AM-Z CP-l CP-1 LMC-I LMC-1 LMC-3 LMO4 RC-I HC-2 RC-3 RC-4
43
86
43
M 301 301 4902 1548 43 2709 2021 129 1548 215
JC-
SlKbhsplo btneilicll
Chiioiiomidae
Collembola
Ainpelisca utilila
Balwiiis crenutus
Cureiniis nitmius
Cuiu/i/ifuui sp.
('. iir/wnu/cuw
C. Ami/iamui
C'nnigiui sepltanplnosa
lis sculpla
llmpaclicoida
Mii-roikulopus sp.
A/, gryllalulpa
OiliacoJa
/'iigMfiK lung/carpus
Sanibalama baluiioliles
('npitlulu sp.
C./um/niM
('. /I/1IIIU
Mmwto Irivilaliis
Iliuietlu sp.
43
43
43
86
172
43
43
86
43
43
43
43
43
43
86
1333
2S8
2322
86
43
43
43
43
43
43
43
43
688
43
129
215
2580
1505
-------
TABLE Al-2. (CONTINUED)
TAXA MP-1 MP-2 RS-t RS-2
Ultoriiiu liitoma
AAvi un'Hiiriii D
Mylilidae ODD
n-l/imi agilis
Ciuna ilileslinalis 86
Alhecala
Obelia dicliolonia f
Nemertinea 43
Nemaloda 11,954 236,672 17,329
Ascidian 43
Miilgulu sp. 43
I'olycutpu fibtvsa 43
Total Abundance 86 17,759 241,230 20,597
Total No. Discrete Taxa' 2 II 13 6
% Polychacla 0 27 2 15
% Crustacea 0 1
-------
TABLE A1-3. MEAN ABUNDANCE (NO./ra1) BY HABITAT OF BENTHIC INFAUNA RETAINED
ON A O.Snm-MESH SIEVE COLLECTED FROM INNER HARBOR LOCATIONS, OCTOBER 1994.
GROUP SPECIES
HO. OF SAMPLES TOTAL
PORIFERA HALICHONORIA PANICEA
HYDROZOA CLYTIA GRACILIS
08ELIA DICHOTOHA
OBELI A SP.
HEHATOOA NEHATODA
POLYCHAETA AHAITIDES SP.
ARICIDEA (ACMIRA)
CATHERINAE
CAPITELLA CAPITATA
CIRRATULIDAE
ETEONE LOHGA
GLYCERA DIBRANCHIATA
HEDISTE DIVERSICOLOR
LEITOSCOLOPLOS ACUTUS
LEITOSCOLOPLOS ROBUSTUS
LEITOSCOLOPLOS SP.
HALDAHIDAE
MARENZELLERIA VIRIDIS
HEDIOMASTUS CALIFORNIENSIS
HICROPHTHALHUS ABERRANS
NEANTHES SUCCINEA
NEANTHES VIRENS
NEPHTYIDAE
NEPHTYS CAECA
NEPHTYS CILIATA
NEPHTYS INCISA
NEREIDAE
HINOE NIGRIPES
PARAMAITIS SPECIOSA
PECTINARIA GOULD 1 1
PECTINARIIDAE
POLYCIRRUS SP.
POLYDORA CORNUTA
POLYDORA SOCIALIS
SPIO FILICORNIS
STREBLOSPIO BENEDICTI
THARYX ACUTUS
OLIGOCHAETA OLIGOCHAETA
GASTROPODA CREPIDULA FORNICATA
CREPIDULA PUNA
CREPIDULA SP.
LACUNA VINCTA
HASSARIUS TRIVITTATUS
AHSTAR
HABITAT
III
2.0
587.5
50.0
12.5
12.5
625.0
412.5
87.5
CHEL 01
HABITAT
III
2.0
87.5
12.5
12.5
50.0
25.0
25.0
'
CHEL 02
HABITAT
III
2.0
25.0
CHELSEA j
CREEK j CONLEY
HABITAT j HABITAT
II ! Ill
5.0! 1.0
P i
i
' P
i
25. Oj 450.0
s.o;
!
i 25.0
i 75.0
10.0J
5.0J
i
i
i
i
i
i
i
i
i
i
i
i
! 25.0
i
j
15.0J 25.0
j 25.0
10.0J
5.0!
! 25.0
|
I
|
5.0{
1
1
5.0!
230.0! 25.0
10.0;
i
i
25.0J 50.0
35.0} 50.0
5.0J 200.0
30.0J
50.0J
10.0;
1
1
CABOT POINT
HABITAT
II
1.0
25.0
s.oj 25-°!
III
1.0
25.0
175.0
75.0
25.0
50.0
i
EVERETT
HABITAT
III
2.0
25.0
12.5
37.5
25.0
37.5
150.0
25.0
REV
H
HAS
I
(CONl
-------
FABLE A1-3. (Continued)
[GROUP SPECIES
BIVALVIA AMOMIA SP.
BIVALVIA
CERASTODERMA PINNULATUM
HIATELLA SP.
j LYONSIA HYALINA
i MACOMA BALTHICA
! • MULINIA LATERALIS
B MYA ARENARIA
\ MYTILIDAE
| TELLINA AGILIS
1 TURTONIA MINUTA
3CIRRIPEDIA BALANUS CRENATUS
BMYSIDACEA HETEROMYSIS FORMOSA
JAMPHIPODA AMPELISCA ABDITA
i COROPHIUM BONELLI
i GAMMARUS LAWRENCIANUS
MICRODEUTOPUS GRYLLOTALPA
PONTOGENEIA INERMIS
i ' UHCIOLA INERMIS
IDECAPODA CRANGON SEPTEMSPINOSA
JBRYOZOA BUGULA TURRITA
IOPHIUROIDEA OPHIUROIDEA
IASCIDIACEA ASCIDIA SP.
{X NO. OF INDIV TOTAL
[X PORIFERA TOTAL
JX HYDROZOA TOTAL
{X NEMATOOA TOTAL
JX POLYCHAETA TOTAL
}X OLIGOCHAETA TOTAL
!X GASTROPODA TOTAL
}X BIVALVIA TOTAL
JX CIRRIPEDIA TOTAL
JX MYSIDACEA TOTAL
JX AMPHIPODA TOTAL
{X DECAPODA TOTAL
JX BRYOZOA TOTAL
JX OPHIUROIDEA TOTAL
JX ASCIDIACEA TOTAL
JNO. OF TAXA ZTOTAL
i
AMSTAR ICHEL 01
HABITAT {HABITAT
HI
50.0
37.5
12.5
25.0
1912.5
587.5
1112.5
87.5
100.0
III
25.0
37.5
275.0
87.5
100.0
25.0
25.0
37.5
'
CHEL 02
HABITAT
III
12.5
37.5
25.0
12.5
25.0! \
CHELSEA j
CREEK J CONLEY
HABITAT {HABITAT
II J III
I
5.0!
1
1
1
j
1
5.0J
5.0J 25.0
5.0!
i
i
i
30.0{ 125.0
j
i
i
i
t
i
10.0J
p j. P
i
545.0J 1150.0
P !
I p
25.0! «0.0
360.0; 325.0
5.0J 200.0
95.0{ 25.0
20.0J 25.0
i
j
30.0{ 125.0
io.oj
p ! p
1
CABOT POINT
HABITAT
II
25.0
25.0
11.0J 8.0J 2.0J 26.0J 16-OJ 1.0
III
25.0
375.0
300,0
50.0
25.0
6.0
EVERETT
HABITAT
III
12.5
25.0
12.5
362.5
25.0
262.5
25.0
37.5
12.5
10.0
REVERE
SUGAR
HABITAT
III
8.3
8.3
483.2
66.7
216.6
183.3
8.3
8.3
9.oi
(CONTINUED)
-------
TABLE A1-3. (Continued)
[GROUP SPECIES
HO, OF SAMPLES TOTAL
PORIFERA HALICHONORIA PANICEA
HYOROZOA CLYTIA GRACILIS
OBELIA DICHOTOHA
OBELIA SP.
NEHATODA NEHATODA
POtYCKAETA AMAITIDES SP.
ARICIDEA CACMIRA)
CATHERINAE
CAPITELLA CAPITATA
CIRRATULIOAE
ETEONE LONGA
GLYCERA DIBRANCHIATA
HEDISTE DIVERSICOLOR
LEITOSCOLOPLOS ACUTUS
LEITOSCOLOPLOS ROBUSTUS
LEITOSCOLOPLOS SP.
HALOAHIDAE
HARENZELLERIA VIRIDIS
KEDIOHASTUS CALIFORNIENSIS
HICROPHTHALMUS ABERRANS
NEAHTHES SUCCINEA
NEAHTHES VIRENS
NEPHTYIDAE
NEPHTYS CAECA
NEPHTYS CILIATA
NEPHTYS INCISA
NEREIDAE
NINOE NIGRIPES
PARANAITIS SPECIOSA
PECTINARIA GOULD 1 1
PECTINARIIDAE
POLYCIRRUS SP.
POLYDORA CORNUTA
POLYDORA SOCIALIS
SPIO FILICORNIS
STREBLOSPIO BENEDICT I
THARYX ACUTUS
OUGOCHAETA OLIGOCHAETA
GASTROPODA CREPIDULA FORMICATA
CREPIDULA PLANA
CREPIDULA SP.
LACUNA VINCTA
INNER CONFLUENCE
HABITAT
II III
3.0
P
25.0
8.3
•
33.3
8.3
16.7
16.7
8.3
8.3
16.7
416.7
166.7
25.0
500.0
33.3
16.7
16.7
2.0
25.0
12.5
LITTLE
MYSTIC-
CHANNEL
HABITAT
III
3.0
P
MYSTIC PIERS
HABITAT
II IV
2.0
'
2.0
12.5
MYSTIC RIVER
HABITAT
III
2.0
P
IV
3.0
P
33.3
RESERVED
CHANNEL
HABITAT
NONE
3.0
58.3
16.7
25.0
375.0
8.3
8.3
50.0
'
8.3
8.3
125.0
8.3
108.3
25.0
(CONTll
-------
BLE A1-3. (Continued)
ROUP SPECIES
5ASTROPODA NASSARIUS TRIVITTATUS
5IVALVIA ANOMIA SP.
BIVALVIA
CERASTOOERHA PINNULATUM
HIATELLA SP.
LYONSIA HYALINA
HACOMA BALTHICA
MULINIA LATERALIS
MYA ARENARIA
HYTILIDAE
TELLINA AGILIS
TURTONIA MINUTA
:iRRIPEDIA BALANUS CRENATUS
1YSIDACEA HETEROHYSIS FORMOSA
IMPHIPODA AMPELISCA ABDITA
COROPHIUH BONELLI
GAHHARUS LAWRENCIANUS
HICRODEUTOPUS GRYLLOTALPA
PONTOGENEIA INERMIS
UNCIOU INERMIS
3ECAPOOA CRANGON SEPTEMSPINOSA
JRYOZOA BUGULA TURRITA
3PHIUROIDEA OPHIUROIDEA
\SCIDIACEA ASCIDIA SP.
< NO. OF INDIV TOTAL
< PORIFERA TOTAL
< HYDROZOA TOTAL
« NEMATODA TOTAL
K POLYCHAETA TOTAL
X OLIGOCHAETA TOTAL
X GASTROPODA TOTAL
X BIVALVIA TOTAL
X CIRRIPEDIA TOTAL
X MYSIDACEA TOTAL
X AMPHIPODA TOTAL
X DECAPOOA TOTAL
X BRYOZOA TOTAL
X OPHIUROIDEA TOTAL
X ASCIDIACEA TOTAL
NO. OF TAXA ZTOTAL
INNER CONFLUENCE
HABITAT
II ! III
250.0!
i
i
8.3!
8.3J
25.0!
8.3J
i
8.3!
t
|
8.3!
i
i
i
i
!
8.3!
i
i
i
i
t
i
8.3!
i
i
i
i
i
i
1649.8 j 37.5
!
P !
25.05
725.0J 37-5
500.0|
316.7!
66.5!
i
8.3!
8.3!
i
i
i
i
LITTLE
MYSTIC-
CHANNEL
HABITAT
III
8.3
8.3
16.6
P
8.3
8.3
i
26.0J 2.0J 3.0
MYSTIC PIERS
HABITAT
II .
37.5
_
37.5
37.5
1.0
IV
12.5
12.5
12.5
12.5
62.5
12.5
12.5
12.5
12.5
12.5
5.0
MYSTIC RIVER
HABITAT
III
P
1.0
. IV
8.3
8.3
8.3
58.2
P
33.3
8.3
8.3
8.3
\ 5.0
RESERVED
CHANNEL
HABITAT
NONE
8.3
41.7
158.3
8.3
1041.4
799.8
25.0
216.6
17.0i
(CONTINUED)
-------
TABLE Al-3. (Continued)
GROUP
NO. OF SAMPLES
PORIFERA
HYDROZOA
NEHATOOA
POLYCHAETA
OLIGOCHAETA
GASTROPODA
SPECIES
HABITAT
TOTAL
HALICHONDRIA PANICEA
CLYTIA GRACILIS
OBELIA OICHOTOMA
OBELIA SP.
NEHATODA
ANAITIDES SP.
ARICIDEA (ACMIRA)
CATHERINAE
CAPITELLA CAPITATA
CIRRATULIOAE
ETEONE LONGA
GLYCERA DIBRANCKIATA
HEOISTE DIVERSICOLOR
LEITOSCOLOPLOS ACUTUS
LEITOSCOLOPLOS ROBUSTUS
LEITOSCOLOPLOS SP.
MALDAHIOAE
HARENZELLERIA VIRIDIS
MEDIOMASTUS CALIFORNIENSIS
MICROPHTHALHUS ABERRANS
HEANTHES SUCCINEA
HEANTHES VIRENS
NEPHTY1DAE
HEPHTYS CAECA
HEPHTYS CILIATA
NEPHTYS INCISA
NEREIDAE
HINOE NIGRIPES
PARAHAITIS SPECIOSA
PECTINARIA GOULDII •
PECTINARIIDAE
POLYCIRRUS SP.
POLYDORA CORNUTA
POLYDORA SOCIALIS
SPIO FILICORNIS
STREBLOSPIO BENEDICTI
THARYX ACUTUS
OLIGOCHAETA
CREPIDULA FORNICATA
CREPIDULA PLANA
CREPIDULA SP.
LACUNA VINCTA
HASSARIUS TRIVITTATUS
REVERE
SUGAR
III
3.0
66.7
108.3
8.3
25.0
50.0
25.0
183.3
CCONl
-------
TABLE A1-3. (Continued)
; GROUP
I
1
1
1
1
1
1
1
i BIVALVIA
i
i
i
i
i
i
i
i
t
t
i
i
i
i
,CIRRIPEDIA
JMYSIDACEA
JAMPHIPODA
1
1
1
1
1
1
i DECAPOD A
IBRYOZOA
JOPHIUROIDEA
JASCIDIACEA
JX HO. OF INDIV
JX PORIFERA
|X HYDROZOA
JX HEMATODA
JX POLYCHAETA
JX OLIGOCHAETA
JX GASTROPODA
|X BIVALVIA
JX CIRRIPEDIA
JX MYSIDACEA
JX AMPHIPODA
|X DECAPODA
JX BRYOZOA
JX OPHIUROIDEA
JX ASCIDIACEA
JNO. OF TAXA
SPECIES
ANOMIA SP.
BIVALVIA
CERASTODERMA PINNULATUM
HIATELLA SP.
LYONSIA HYALINA
HACOMA BALTHICA
MULINIA LATERAL IS
MYA ARENARIA
MYTILIDAE
TELLINA AGILIS
TURTONIA MINUTA .
BALANUS CRENATUS
HETEROMYSIS FORMOSA
AHPELISCA ABDITA
COROPHIUM BONELLI
GAMMARUS LAWRENCIANUS
MICRODEUTOPUS GRYLLOTALPA
PONTOGENEIA INERMIS
UNCIOLA INERMIS
CRANGON SEPTEMSPINOSA
BUGULA TURRITA
OPHIUROIDEA
ASCIDIA SP.
TOTAL
TOTAL
TOTAL
TOTAL
. TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
ZTOTAL
REVERE
SUGAR
HABITAT
III
8.3
8.3
483.2
66.7
216.6
183.3
8.3
8.3
9.0
-------
Table A1-4. Standardized mean catch per unit effortCcatch per 20 minute trawl)
by station in Boston Harbor and Massachusetts Bay, October 1994.
j SPECIES
i
i
i
ALEWIFE
ATLAHTIC COO
ATLANTIC HOONFISH
ATLANTIC SILVERS1DE
ATLAMTIC TOMCOD
BUTTERFISH
CUWHER
GaUSSr
BAKE SP.
LOBSTER
LOWGHCRH SCULPIN
RAINBOW SMELT
SCOP
SHORTHORN SCULP I M
SILVER HAKE
SKATE SP.
STRIPED BASS
WINDOWPANE
UtHTER FLOUNDER
YELLOUTAIL FLOUNDER
STATIOM TOTAL
PERCENT STATION-
STATION
i
i
1
1
BOSTON- {SUBAQUEOUS- |
LIGHTSHIP i
0.3|
0.0!
O.Oj
o.o;
o.o|
4.0;
o.o;
o.o;
1.7!
37.7J
0.7!
o.o;
o.o;
o.o ;
0.7{
o.o!
o.o;
o.o;
17.7]
1.7!
64.3!
I
1
COHPOSITION 22.4J
E !
O.Oj
1.3!
o.o;
2.3!
o.o;
o.o;
o.o;
o.o;
O.Oj
3.7;
O.Oj
2.7!
O.Oj
O.Oj
O.Oj
5.0J
0.3!
0.3!
5.0!
o.o;
20. 7 J
1
7-2}
1
SPECTACLE- j
I. CAD* j
O.Oj
o.o;
O.Oj
1.3J
O.Oj
O.Oj
O.Oj
o.o;
o.o;
6.7!
o.o;
4.0;
O.Oj
o.o;
O.Oj
6.7!
O.Oj
o.o;
9.3;
o.o;
28.0 !
i
i
9.7;
1
I
INNER- !
CONFLUENCE*!
1.3!
o.o;
O.Oj
1.3!
o.o|
O.Oj
O.Oj
1.3J
o.o|
2.7J
o.o;
4.0;
o.o;
o.o;
O.Oj
1.3!
o.o;
5.3;
22.7!
O.Oj
40.0J
I
1
13.9!
i
MYSTIC- ,'
RIVER* !
4.0!
O.Oj
5.3!
2.7J
10.7J
o.o;
1.3!
o.o;
o.o;
o.o;
o.o;
2.7;
9.3!
o.o;
o.o;
o.o;
O.Oj
o.o;
26.7J
o.o;
62.7J
I
1
21.8J
1
1
CHELSEA- !
RIVER* !
O.Oj
o.o;
o.o ;
o.o;
16. Oj
O.Oj
o.o;
2.7J
O.Oj
4.0;
o.o;
O.Oj
O.Oj
1-3!
o.o;
1 ^'
i.o,
o.o;
o.o;
46.7!
o.o ;
72. 0!
;
25.0J
1
SPECIES- I
TOTAL j
5.7!
1.3J
5.3J
7.7J
26.7J
4.0J
1.3j
4.0{
1.7J
54.7J
0.7J
13.3!
9.3!
1.3J
0.7!
14.3 j
0.3J
5.7J
128.0 j
1.7J
287. 7!
j
i
• i
i
i
PERCENT- !
SPECIES- !
COMPOSITION!
2.0J
0.5!
1.9J
2.7!
9.3J
1.4!
0.5!
1.4J
0.6!
19.0}
0.2;
4.6!
3.2!
o.s;
0.2J
5.0J
0.1!
2.0;
44.5J
0.6}
1
1
1
100.0!
* Five minute tows standardized to 20-minute tows.
($34,
-------
TABLE Al-5. REPRESENTATIVE FINFISH SPECIES LIST,
BOSTON INNER AND OUTER HARBOR.
Common Name
Alewife
American plaice
American shad
Atlantic wolfish
Atlantic cod
Atlantic herring
Atlantic mackerel
Atlantic menhaden
Atlantic silverside
Atlantic tomcod
Bluefish
Blueback herring
Butterfish
Gunner
Cusk
Grey sole
Hake
Skate spp.
Longhom sculpin
Ocean pout
Pollock
Rainbow smelt
Redfish
Sculpin
Scientific Name
Alosa psevdoharengus
Hippoglossoides platessoides
Alosa sapidissima
Anarhichas lupus
Gadus morhua
Clupea harengus harengus
Scomber scombnts
Brevoortia tyrannus
Menidia menidia
Mlcrogadas tomcod
Pomatomus saltatrix
Alosa aestivalis
Peprilus triacanthus
Tautoglabrus adspersus
Brosme brosme
Glyptocephalus cynoglosstts
Urophycis sp.
Raja spp.
Myoxocephalus octodecemspmosus
Macrozoarces americamis
Pollachius virens
Osmerus mordax
Sebastes spp.
Myoxocephalus sp.
(Continued)
-------
TABLE Al-5. (CONTINUED)
Common Name
Scup
Spiny dogfish
Striped bass
Tautog
Whiting/Silver hake
Windowpane
Winter flounder
Yellowtail flounder
Scientific Name
Stenotomus chrysops
Squalvs acanthias
Morons saxatilis
Tautoga onitis
Merluccius bilinearis
Scophthalmus aqousus
Pleuronectes americamts
Limandafermginea
(Continued)
-------
Table A1-6. Standardized catch per unit effortCfish per 24-hour set) in gill net
collections from Boston Harbor and Massachusetts Bay, October 1994.
[SPECIES
i
i
i
i ,
i
i
j— H
IALEWIFE
{AMERICAN SHAD
{ATLANTIC COO
{ATLANTIC TOMCOD
{BLUE RUNNER
IBLUEBACK HERRING
JBLUEFISH
{BUTTERFISH
j GUNNER
{GREEN CRAB
{GRUBBY
{HAKE SP.
{HORSESHOE CRAB
{LOBSTER
{LONGHORN SCULP I H
{MACKEREL
{MACKEREL SCAD
{RAINBOW SMELT
{SCUP
{SILVER HAKE
{SKATE SP.
{SPIDER CRAB
{STRIPED BASS
{WINTER FLOUNDER
{STATION TOTAL
{PERCENT STATION-
! COMPOSITION
STATION i
i
RESERVED-! CHELSEA
CHANNEL j 01
28.7{
0.7{
.{
0.7\
0.3{
52.0 { 0.3
3.7{ . 0.3
0.3 {
.{ 1.7
.{ 2.0
• !
1.0{
• i »
.{ 0.3
i
"i '•
0.3{
3.3{ 15.3
t
• i
i
• i
i n<
1 .U | •
1.0J
I.Oj 0.3
2.7J 2.0
96.7J 22.3
!
FISH PIER
0.3
0.3
•
0.7
.
.
0.3
•
»
•
•
18.3
.
•
—
—
m
f
*
20.3
i
LOGAN 2
o
•
•
0.3
.
0
.
0.3
«
0.3
6.3
.
m
1.7
—
0.7
3.7
13.7
LITTLE-
MYSTIC-
CHANNEL
0.3
^
1.0
•
•
0.7
0.3
0.3
4.7
•
»
»
*
.
^
7.3
-
REVERE-
SUGAR
0.3
•
•
•
.
•
•
^
^
m
0.3
3.0
0.3
4.7
47.4! 10-°! 10.0J 6-7J 3.6J 2.3
MEIS-
BURGER 2
0.7
.
•
.
.
3.6
•
5.0
2.0
6.3
•
0.3
17.3
8.5
! { PERCENT-"
MEIS- { SPECIES-! SPECIES-!
BURGER 7 J TOTAL { COMP. {
0.3J 30.7J 15.0{
• i 0.7J 0.3{
1.3| 1-3! 0.7}
- i 2.0{ 1.0[
. ! 0.3J 0.2{
-! 53.3J 26.1}
.{ 4.0J 2.0}
.{ 1.0J 0.5}
0.3{ 5.7{ 2.8{
•! 2.0{ 1.0J
. ! 0.3; 0.2;
1.0! 2.0{ 1-oj
.! 0.3J 0.2{
4.3J 10. 0{ 4.9{
0.7{ 2.7J 1-3!
12.3 { 19.0{ 9.3 {
.{ 0.3{ 0.2{
.{ . 51.0} 25.0!
0.3{ 0.3} 0.2{
0.3{ 0.3{ 0.2{
0.7{ 3.3{ 1.6{
.{ 1.0J 0.5!
-! 2.0} 1.0}
.{ 9.0{ 4.4{
21. 7{ 204.0{ .{
! ! !
io.6{ •! ioo.o{
ft/-a.
-------
Table A1-7. Catch per unit effort (number/trap-day) by sex
for sufalegal and legal sized lobsters captured in
Boston Harbor, October 1994.
SUBLEGALS
SEX
{ Inner-
LHCh. j Conf.
KALES | 0.4! 0.8
FEMALES 0.1 j 0.1
TOTAL j 0.6| 0.9
LOCATION
! Chel.- i | j j j Outer- | | |
Chel-01 j Riv. JHystieR. [RevSug. j ResCh \ Log02 \ Hbr. {Specls. | Meis#2 j Meis#7 BLS
o.o; 0.1; 0.2;
0.1; o.o| 0-0!
0.1; 0.1; o.2|
0.1J 0.7! 0-7"! O.Oj 0-2! 2.8! 2.3 1.3
0.1J 0.6J 0.1J O.Oj 0-0! 3.5J 2.7J 1.5
0.2J 1.2{ 0.8! 0.0! 0.2J 6.3 j 5.0J 2.8
.EGALS
SEX
KALES
FEMALES
TOTAL
rOTAL
SEX
HALES
FEMALES
TOTAL
LHCh. J
0.6;
0.0!
0.6!
1
LMCh. i
O^l
1.1!
Inner- \
Conf. !
o.o;
O.Oj
o.o;
Inner- \
Conf. j
o'.i\
0.9J
t
Chel-01 J
O.Oj
o.o;
o.o;
1
Chel-01 ;
o.o;
0.1;
0.1;
Chel.- J
Riv. ]
o.o;
o.i|
0.1|
Chel.- [
Riv. j
0.1;
0.1]
0.2!
1
1
MysticR. j
o.o;
O.Oj
o.o!
1
MysticR. j
0.2J
O.Oj
0.2J
i
RevSug. {
0.1J
o.o!
0.1|
RevSug . {
0.2J
0.1!
0.3!
LOCATION
ResCh !
0.2!
o.o;
0.2!
LOCATION
ResCh j
0.9!
0.6J
1.4J
Log02 j
O.Oj
o!ij
i
Log02 !
0.7J
0.2!
0.9J
Outer- j
Hbr. i
0.0]
Outer- j
Hbr. i
0.0!
0.0!
0.0!
Specls. j
o.oj
o.oj
o.o!
i
Specls. i
0.2!
o.o[
0.2[
Heis#2 !
0.1!
O.O,1
0.1J
Meis#2 |
2.9J
3.5!
6.4J
Meis#7 J
0.1!
0.0]
0.1!
Meis#7 !
2.4!
2.7!
5.1!
BLS
0.1
0.1
0.1
BLS
1.4
1.5
2.9
-------
TABLE Al-8. SHORELINE SITE FOOTPRINT
SITE
FOOTPRINT
(acres)
Amstar
Cabot Paint
Little Mystic Ch.
Mystic Piers
Reserved Channel
Revere Sugar
3.5
5.6
15.0
2.7
7.7-16.6
3.7
-------
W
TABLE Al-9. SEDIMENT CHARACTERISTICS IN THE VICINITY OF POTENTIAL DISPOSAL
SITE EAST OF SPECTACLE ISLAND, 1988s.
cO
PARAMETER11
Arsenic
Cadmium
Chromium
Copper
Lead
Mercury
Nickel
Vanadium
Zinc
% Water
% Volatile Solids
% Oil and Grease
Total Petroleum Hydrocarbons
% Total Organic Carbon
Polychlorinated Biphenyls
% Silt/Clay
Classification
ST1-7
(0-2')b
9.2
0.7
16.0
8.7
7.5
<0.01
15.5
22
32.2
27
3
0.042
<100
0.52
TR
48
1A
ST1-8
(0-1')
14.8
0.8
19.2
18.0
14.4
0.06
15.8
23
35.8
26
2
0.032
200
1.40
0.02
23
2A
ST1-8
(1-6.25')
27.8
0.8
25.3
17.1
10.1
<0.01
23.5
39
41.2
37
2
0.020
100
1.20
ND
50
3A
ST1-9
(0-2')
3.8
<0.5
12.1
5.3
9.5
0.02
10.5
17
64.0
27.6
0.8
0.080
<100
0.60
ND
31
1A
ST1-11
(0-2')
2.5
0.8
19.1
22.4
16.1
0.11
20.1
20
37.7
24
9
0.025
<100
0.64
TR
21
IB
ST1-12
(0-1.5')
13.1
2.8
20.9
14.1
11.7
0.06
22.8
37
53.8
20
2
<0.010
<100
0.77
ND
7
2A
Source: Cortell 1990b
aAll results in mg/kg (ppm) dry weight unless otherwise noted.
bDepth below sediment surface
TR = Traces below detection limit
ND = Not detected
-------
TABLE A1-10. MEAN ABUNDANCE BY HABITAT OF BENTHIC INFAUNA RETAINED ON A
0.5mm-MESH SIEVE COLLECTED FROM OUTER BOSTON HARBOR LOCATIONS, OCTOBER 1994.
GROUP
NO. OF SAMPLES
HYDROZOA
NEMERTINEA
NEMATODA
POLYCHAETA
/
SPECIES
TOTAL
CLYTIA GRACILIS
EUDENDRIUM RUGOSUM
SERTULARIA CUPRESSINA
NEMERTINEA
NEMATODA
AGLAOPHAMUS NEOTENUS
AMPHARETE ARCTICA
AMPHARETIDAE
ANAI TIDES MUCOSA
ANOBOTHRUS GRACILIS
APHELOCHAETA MARIONI
ARICIDEA CACMIRA)
CATHERINAE
ARICIDEA SP.
ASABELLIDES OCULATA
CAPITELLA CAPITATA
CIRRATULIDAE
CIRRATULUS CIRRATUS
CLYMENELLA TORQUATA
EN IPO TORELLI
ETEONE LONGA
EUCHONE ELEGANS
EULALIA VIRIDIS
GATTYANA CIRROSA
HARMOTHOE IMBRICATA
LEITOSCOLOPLOS ACUTUS
MALDANIDAE
MEDIOMASTUS CALIFORNIENSIS
MICROPHTHALMUS ABERRANS
NEANTHES VIRENS
NEPHTYIDAE
NEPHTYS CAECA
NEPHTYS CILIATA
NEPHTYS INCISA
NEREIDAE
NICOLEA ZOSTERICOLA
NINOE HI GRIPES
PARANAITIS SPECIOSA
PHERUSA AFFINIS
PHOLOE MINUTA
PHYLLODOCIDAE
POLYDORA CORNUTA
POLYDORA QUADRILOBATA
SPECTACLE ISLAND
HABITAT
I ! II
4.0[ 1.0
i
i
i
i
P i
62.5!
1325.0J 325.0
! 50.0
6.3!
6.3!
650. Oj 300.0
6 3'
°-->t
j
i
i
9668.8! 3075.0
i
i
143.8J 150.0
81.3! 25.0
1787.5! 450.0
i
i
j 200.0
!
381.3J 100.0
! 25.0
i
i
[ 50.0
1
1
1
568. 8 j 200.0
[ 25.0
I
I
6.3!
6.3J 675.0
206.3J 325.0
!
12.5J
i
175.0', 50.0
6.3} 25.0
i
i
100.0;
!
4706.3} 14400.0
25.0! 1850.0
SUBAQUE- !
OUS B j SUBAQUEOUS E
HABITAT J HABITAT
I j I j II
3.0{ 2.0] 1
! PI
! P !
PI P !
166.7J 25. Oj
483.3J 2012.5! 50
j 25.0J
i i
i i
] j
2075.0! 625.0!
i i
! 287.5!
i i
i i
1041 .7j !
8.3J 12.5J
41.7J 212.5J 25
108.3} 537.5!
483.3J 3362.5J 25
i 12-5!
8.3} 25.0J
16. 7j [
300.0! 1087.5!
i i
i i
8.3! i
16.7J !
41.7J 87.5J
! j 50
{ 37.5!
533.3} 462.5J
! 12.5!
16.7J 75. Oj 25
i i
i i
! ! 25
25.0} 75-0! 200
8.3J 12.5J
i i
8.3] !
41.7J 50.0] 150
! 12.5!
41.7J !
125.0J 475.0!
8.3! !
4625.0J 9300.0J
8.3J !
.0
.0
.0
.0
.0
.0
.0
.0
.0
(CONTINUED)
-------
TABLE A1-10. (Continued)
| GROUP
i
!
!
!
!
JPOLYCHAETA
i
l
!
!
!
!
!
!
I
!
i
!
!
t
i
I
JOUGOCHAETA
j GASTROPODA
!
i
! BIVALVIA
i
i
|
i
1
i
l
JCIRRIPEDIA
JHYSIDACEA
!
!
JCUHACEA
JISOPODA
!
i
l
IAHPHIPOOA
!
!
!
i
i
!
i
i
i
i
i
i
!
SPECIES !
POLYDORA SOCIALIS
POLYDORA WEBSTER!
PRIONOSPIO STEENSTRUPI
SCOLELEPIS TEXAMA
SCOLETOMA ACICULARUM
SCOLETOHA HEBES
SPIO FILICORNIS
SPIO LIHICOLA
SPIO SP.
SPIO THULINI
SPIONIDAE
SPIOPHANES BOMBYX
STREBLOSPIO BENEDICTI
TEREBELLIDAE
THARYX ACUTUS
OLIGOCHAETA
GASTROPODA
LACUNA VINCTA
NASSARIUS TRIVITTATUS
BIVALVIA
CERASTODERMA PINNULATUM
LYONSIA HYALINA
MYA ARENARIA
MYSELLA PLANULATA
MYTILIDAE
TELLINA AGILIS
CIRRIPEDIA
HETERYTHROPS ROBUSTA
HYSIDACEA
NEOMYSIS AMERICANA
DIASTYLIS SP.
CHIRIDOTEA SP.
CYATHURA POLITA
EDOTEA TRILOBA
AMPELISCA SP.
AMPHIPODA
COROPHIUH BONELLI
COROPHIUM CRASSICORNE
COROPHIUM SP.
ERICHTHONIUS FASCIATUS
GAMMARUS SP.
JASSA MARMORATA
LEPTOCHEIRUS PINGUIS
SPECTACLE
[SUBAQUE-!
ISLAND j OUS B |
HABITAT j HABITAT j
I !
18.8]
6.3 J
6.3|
i
i
!
i
6.3|
i
i
25.0J
18.8]
i
i
i
81 .3j
i
i
1543. 8j
1475.0J
50.0{
12.5J
1
1
25.0J
i
i
!
i
i
31.3!
j
i
6.3[
6.3!
i
i
i
i
6.3J
6.3!
37.5!
36537.5 J
6.3J
700.0!
56.3}
50. Oj
6.3!
87.5!
6.3!
1250.0J
LEPTOCHEIRUS SP. \ \
II ! I [
1175.0! 8.3J
i i
i i
! 8.3[
75.0J !
25.0! !
! soo.o!
1 1
1 1
25.0! !
25.0J 16-7!
175.0! 66-7J
50.0J 16.7J
25.0J !
11800.0} 16.7J
! !
575.0 1733.3!
250.0
200.0
25.0
25.0
50.0
50.0
61675.0
75.0
25.0
3100.0
1033.3 j
50.0|
i
. i
33.3!
8.3!
33.3!
i
i
8.3J
41.7J
i
i
8.3J
i
25.0{
33.3!
8.3!
!
i
i
116.7!
94358.3J
i
i
i
i
i
i
i
i
i
i
i
1883.3J
8.3!
SUBAQUEOUS
HABITAT
I !
12.5!
!
75.0{
!
25.0J
1
1
1
1
1
25.0J
262. 5 i
i
i
i
i
550.0]
12.5J
6025.0J
287.5J
125.0}
25.0j
287.5!
62.5J
i
i
25.0!
37.5J
150.0J
125.0J
i
i
i
i
i
i
i
i
i
i
i
i
i
25.0J
23075. Oj
!
i
t
i
i
i
i
i
12.5J
!
637.5}
i
E
II
25.0
50.0
250.0
25.0
50.0
(CONTINUED)
-------
TABLE A1-10. (Continued)
[GROUP
i
i
i
JAMPHIPODA
i
i
i
!
t
i
! DECAPODA
i
i
i
JBRYOZOA
j
i
i
i
{X NO. OF INDIV
JX HYDROZOA
JX NEMERTINEA
JX NEMATODA
!X POLYCHAETA
[X OLIGOCHAETA
JX GASTROPODA
JX BIVALVIA
JX CIRRIPEDIA
JX MYSIDACEA
JX CUMACEA
JX ISOPODA
JX AMPHIPODA
JX DECAPODA
JX BRYOZOA
JNO. OF TAXA
SPECIES
LYSIANASSIDAE
ORCHOMENELLA PINGUIS
PHOTIS POLLEX
PHOXOCEPHALUS HOLBOLLI
PHOXOCEPHALUS SP.
UNCIOLA IRRORATA
UNCIOLA SP.
CANCER IRRORATUS
CRANGON SEPTEMSPINOSA
DECAPODA
BUGULA TURRITA
MEMBRANIPORA MEMBRANACEA
PEDICELLINA CERNUA
SCRUPARIA AHBIGUA
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
i
SPECTACLE ISLAND
HABITAT
I ! II
31.3[
6.3!
81.3J
2062.5! 125.0
i
368.8! 175.0
306.3!
6.3{
6.3J
6.3J
1
I
P !
1
I
1
I
64870.6! 102025.0
P !
62.5}
1325.0J 325.0
20251.0', 35925.0
1475.0! 250.0
62.5J 200.0
56.3J 100-0
i
12.6',
i
i
50.1! 50.0
41556.7! 65175.0
18.9!
SUBAQUE- !
OUS B j SUBAQUEOUS E
HABITAT [ HABITAT
I ! I II
108.3!
33.3{
16.7J
2850.0! 212.5
8.3}
1550.0}
266.7J 37.5
33.3J 12-5 25.0
25.0! 37.5
i
i
P !
!
P !
! p
115149.6! 50987.5 975.0
P ! P
166.7! 25.0
483.3! 2012.5 50.0
11958.3J 23775.0 525.0
1033.3J 287.5 50.0
50.0! «7.5 250.0
124.9J 400.0 75.0
8.3!
58.3!
8.3{
116.7! 25.0!
101083.2} 23975.0!
58.3} 50.0! 25.0
P ! ! P i ! P
59.0{ 41.0{ 60.0} 51.0J 15.0J
-------
TABLE A1-11. MEAN ABUNDANCE CNO./m2) BY HABITAT OF BENTHIC INFAUNA RETAINED
ON A 0.5mm-MESH SIEVE COLLECTED FROM OFFSHORE LOCATIONS, OCTOBER 1994.
6ROUP SPECIES
HO. OF SAMPLES TOTAL
PORIFERA SCYPHA CILIATA
HYDROZOA CLYTIA GRACILIS
EUOENDRIUM RUGOSUH
EODENDRIUM SP.
SERTULARIA CUPRESSINA
AHTHOZOA ANTHOZOA
CERIANTHEOPSIS AHERICANUS
CERIANTHEOPSIS SP.
EDWARDSIA SP.
NEHERTINEA NEHERTINEA
NEHATOOA NEHATODA
ARCHIANNELIDA ARCHIANNELIDA
POLYCHAETA AGLAOPHAHUS CIRCINATA
AHPHARETE ACUTIFRONS
AHPHARETE ARCTICA
AHPHARETE SP.
AHPHARETIDAE
AHPHITRITE CIRRATA
AMAITIDES ARENAE
ANAITIDES HACULATA
AMAITIDES HUCOSA
AH060THRUS GRACILIS
APHELOCHAETA MARION I
APHELOCKAETA HONILARIS
APISTOBRANCHUS TULLBERGI
ARCTEOBIA ANTICOSTIENSIS
ARICIDEA (ACMIRA)
CATHERINAE
ARICIDEA QUADRILOBATA
ASABELLIDES OCULATA
BARANTOLLA AMERICANA
CAPITELLA CAPITATA
CAULLERIELLA CF.
KILLARIENSIS
CHAETOZONE SETOSA
CHONE DUNERI
CIRRATULIDAE
CIRRATULUS CIRRATUS
COSSURA LONGOCIRRATA
DRILONEREIS LONGA
DRILONEREIS MAGMA
ENIPO TORELLI
ETEONE LONGA
EUCHONE ELEGANS
BOSTON LIGHTSHIP
HABITAT
VII j VIII
8.0\ 3.0
i
i
! P
j
i
P !
25.0|
i 8.3
i
i
9.4| 41.7
62.5 i 50.0
71.9|
I
|
3.1!
53.1[ 8.3
75.0J 33.3
9.4!
25.0! 16.7
i
i
3.1!
28.1]
6.3|
140.6[ 433.3
171.9! 308.3
3.1!
3.1J
12.5! 8-3
i
i
i
i
28.1J
331.3} 91.7
i
6.3[
i
i
21.9J 8.3
i
3.1! 8.3
3.1!
3.1!
6.3J 33.3
|
9.4J 8.3
43.8!
i
i
HEISBURGER 2 ! HEISBURGER 7
HABITAT ! HABITAT
V
1.0
25.0
50.0
50.0
25.0
725.0
150.0
175.0
400.0
350.0
vii j vni i v | vi ! vn
6.0J 2.0J 2.0{ 4.0J 1.0
12.5! { ! !
1 1 I 1
Illj
P ! ! ! !
P ! i ! i
P ! ! P ! i
20.8! [ ! ! 25.0
12.5! ! I2-5! ! 25.0
16.7! ! ! !
66.7! 62.5[ 25.0J ! 100.0
137.5! 162.5J 12.5! 31 .3 |
91.7J ! ! 31.3J
45.8J ! i 12-5!
12.5 j 37.5! ! 6.3! 300.0
: : i i
112.5! 75-0! 37.5! 6.3J 25.0
! i ! !
29.2! 87.5} 37.5J 31.3! 125.0
4.2J ! ! !
! i ! i
37.5! 50.0! 37.5J 25.0!
29.2J ! 12-5! 18-8! 75.0
29.2J 25.0J 12-5! 6.3J
858.3! 1950.0J 12.5! 12-5} 50.0
29.2! 75.0! ! 6.3 1
i i i i
i i i i
4.2! 12-5! ! !
: : : i
50.0! 37.5J 275.0! 75.0! 25.0
i i i i
i i i i
337.5J 400.0! 225.0J 368.8! 975.0
4.2! ! ! !
50.0J 175.0J ! ! 50.0
: : : :
! i ! 12-5!
25.0! 62.5J ! 6.3', 125.0
j 12.5J ! 6.3!
16.7J 100.0J 200.0J 25.0j 75.0
4.2J 12-51 12.5! !
i i i i
iiii
4.2! ! ! !
! j 12.5! !
! ! ! 6.3!
100.0! 41.7! 12-5! ! 6.3!
1050.0! 54.2J 2437.5J 112.5! 331.3} 175.0
(CONTl
L2.L,
-------
FABLE A1-11. (Continued)
GROUP SPECIES
IPOLYCHAETA EUCHONE INCOLOR
i EUCHONE SP.
j EUCLYMENE COLLARIS
EULALIA BILINEATA
EUSYLLIS SP.
! EXOGONE D I SPAR
> EXOGONE HEBES
i EXOGONE SP.
j EXOGONE VERUGERA
! GALATHOWENIA OCULATA
.GATTYANA AMONDSENI
GATTYANA CIRROSA
GLYCERA CAPITATA
GONIADA MACULATA
HARMOTHOE I HER I CAT A
HETEROMASTUS FILIFORMIS
LAGISCA EXTENUATA
| LAONICE CIRRATA
| LAONOME KROYERI
LEITOSCOLOPLOS ACUTUS
j LEVINSENIA GRACILIS
I LYSILLA LOVENI
I MALDANE SARSI
[ MALDANIDAE
j MARENZELLERIA VIRIDIS
| MEDIOMASTUS CALIFORNIENSIS
[ MICROPHTHALMUS ABERRANS
I MINUSPIO CIRRI FERA
[ MONTICELLINA BAPTISTAE
I MONTICELLINA
E DORSOBRANCHIALIS
E MYRIOCHELE HEERI
E NEPHTYIDAE
E NEPHTYS CAECA
E NEPHTYS CILIATA
E NEPHTYS INCISA
E NEREIS GRAYI
E NEREIS SP.
I NEREIS ZONATA
E NINOE NIGRIPES
I OPHELINA ACUMINATA
I ORBINIIDAE
I OUENIA FUSIFORMIS
E PARADONEIS LYRA
BOSTON LIGHTSHIP [
HABITAT !
VII !
12.5!
1
12.5J
i
i
i
i
i
i
i
i
6.3[
46.9J
15.6[
t
I
31.3!
3.1!
9.4!
i
i
i
i
37.5!
56.3J
193.8!
15.6J
56.3]
93.8{
3.1!
631.3J
1
1
9.4}
i
i
i
3.1J
9.4|
I
t
I
i
56.3[
3.1 j
18. 8j
3.1!
118.8!
3.1J
3.1!
i
i
i
i
vni !
1
1
j
j
•
i
i
i
i
i
t
t
i
116.7J
8.3J
i
i
i
i
i
8.3!
8.3!
t
I
33.3!
16.7!
33.3J
j
441.7J
50.0J
i
41.7',
i
i
i
i
j
i
8.3!
i
i
i
t
i
i
58.3!
i
i
i
!
125.0J
1
1
1
16.7!
i
i
MEISBURGER 2
HABITAT
V
475.0
150.0
50.0
25.0
150.0
75.0
100.0
400.0
25.0
25.0
VII !
i
t
125.0J
200.0;
!
i
4.2!
i
8.3{
29.2J
12.5[
12.5J
16.7!
16.7{
8.3!
16.7J
1
4.2!
16.7J
8.3!
154.2!
25.0J
i
i
308.3!
j
i
600.0J
4.2J
i
i
i
25.0J
i
i
4.2]
!
j
8.3!
1
1
29.2J
i
i
250. OJ
1
1
1
1
12.5}
!
1
I
1
1
VIII i
I
I
725.0J
12.5{
j
i
i
50.0J
25.0}
187.5J
i
i
12.5!
i
i
i
12.5J
i
i
!
j
37.5',
100.0}
1
1
1
1
37.5',
25.0J
i
soo.o;
1
1
1
1
12.5J
12.5!
i
12.5J
50.0!
!
12.5[
112.5}
25.0J
250.0!
i
i
i
!
MEISBURGER 7
HABITAT
V
450.0
37.5
50.0
287.5
12.5
37.5
100.0
37.5
37.5
37.5
12.5
450.0
37.5
vi j
1
1
56.3J
575.0!
i
i
12.5!
18.8!
6.3!
18.8|
412.5 j
i
i
i
i
i
i
112.5J
i
i
6.3}
i
i
18.8!
i
i
i
i
6.3!
50.0J
1
1
1
93.8}
t
i
81.3J
1
1
6.3!
!
j
37.5J
!
!
!
!
!i
i
j
!
j
75.0!
t
i
i
i
i
VII
975.0
25.0
25.0
25.0
25.0
25.0
25.0!
1 (CONTINUED)
-------
TABLE A1-11. (Continued)
GROUP SPECIES
POLYCHAETA PARAPIONOSYLLIS
LONGICIRRATA
PECTINARIA GRANULATA
PHERUSA AFFINIS
PHOLOE HIKUTA
PHYLLOOOCIDAE
POLYCIRRUS MEDUSA
POLYCIRRUS PHOSPHOREUS
POLYCIRRUS SP.
POLYDORA CAULLERYI
POLYDORA CONCHARUM
POLYDORA CORNUTA
POLYDORA QUADRILOBATA
POLYDORA SOCIALIS
POLYDORA SP.
POLYNOIDAE
PRAXILLELLA PRAETERHISSA
PRAXILLURA ORNATA
PRIONOSPIO STEENSTRUPI
PROTODORVILLEA GASPEENSIS
RHODINE BITORQUATA
SABELLIDAE
SCALIBREGMA INFLATUM
SCHISTOMERIKGOS CAECA
SCOLETOHA ACICULARUM
SCOLETOHA FRAGILIS
SCOLETOHA HEBES
SCOLOPLOS ARHIGER
SPHAEROSYLLIS SP.
SPIO FILICORNIS
SPIO LIHICOLA
SPIO SETOSA
SPIO SP.
SPIO THULINI
SPIONIDAE
SPIOPHANES BOMBYX
SPIOPHAHES KROYERI
STERNAPSIS SCUTATA
SYLLIDAE
SYLLIS
(TYPOSYLLIS)ALTERNATA
TEREBELLIDAE
TEREBELLIDES ATLANTIS
TEREBELLIDES STROEHI
THARYX ACUTUS
BOSTON LIGHTSHIP j HEISBURGER 2
HABITAT j HABITAT
VII j VIII ! V
! !
i i
i i
i i
i i
i i
12.5| 8.3J 75.0
: :
I 1
1 I
3.1! !
6.3J 16.7] 50.0
! ! 50.0
! 16.7J
I I
! j 1225.0
103.1J 33.3J 925.0
i i
i t
• 33.3!
90.6! !
.537.5) 66.7J 1125.0
1 |
I |
25.0J i 25.0
3.1! 16.7! 100.0
203.1J 41.7J 150.0
i a
i i
i i
r i
15.6J 66.7J
3.1! !
15.6{ 8.3!
i i
i i
! i 25.0
4268.8J 991.7J 50.0
i t
i i
56.3J 25.0J
3.1J ! 100.0
50.0J 25.0] 25.0
! i 25.0
15.6! 58.3!
3.1! 8.3J
i i
! !
: :
18.8! 8.3J.
21.9J 16-7J
15.6J 41.7J
vii ! vin
1
i
25.0! 12.5
! 37.5
33.3J
16.7!
i
i
L. ?'
«.£|
20.8J
8.3} 12-5
i
i
4.2!
991.7! 4025.0
816.7J 1337.5
i
i
i
i
45.8J
!
250.0J 812.5
i
1 75.0
8.3J 112-5
170.8! 112.5
i
i
i
i
29.2J 37.5
j
8.3] 50.0
i
i
20.8J 25.0
541.7J 675.0
4.2[
20.8!
66.7! 50.0
45.8J 50.0
16.7J 37.5
! 12.5
!
! 12.5
i
i
33.3!
i
i
i
i
i
i
HEISBURGER 7
HABITAT
V
37.5
12.5
312.5
37.5
787.5
12.5
12.5
12.5
25.0
150.0
12.5
62.5
12.5
VI j VII
I
1
6.3!
i
i
i
i
31.3J
i
i
6.3J
t
t
i
i
6.3J
i
i
i
i
! 25.0
62.5! 400.0
6.3[
6.3J
18.8]
i
12.5 i 100.0
6.3J
287.5! 600.0
j
6.3!
6.3J
i
i
!
I
; 100.0
12.5!
1
31.3J 675.0
i
i
12.5J
87.5J 75-0
6.3J
12.5J 1100.0
!
,1
1
1
1
!
i
i
i
i
i i
i i
i i
15.6! ! 100.0! 25.0J 50.0J 75-0! 200.0! 25.0!
(CONTll
-------
('ABLE A1-11. (Continued)
GROUP SPECIES
POLYCHAETA TRICHOBRANCHUS ROSEUS
TROCHOCHAETA MULTISETOSA
TROCHOCHAETA SP.
TYPOSYLLIS SP.
OLIGOCHAETA OLIGOCHAETA
GASTROPODA ALVANIA EXARATA
BUCCINUM UNDATUM
COLUS PUBESCENS
COLUS SP.
CREPIDULA FORNICATA
GASTROPODA
LACUNA VINCTA
LUNATIA HEROS
MARGARITES HELICINUS
NASSARIUS TRIVITTATUS
OENOPOTA DECUSSATA
RETUSA OBTUSA
TURRIDAE
POLYPLACOPHORA ISCHNOCHITON ALBUS
BIVALVIA ANOMIA SP.
ARCTICA ISLAND I CA
ASTARTE BOREALIS
ASTARTE SP.
ASTARTE UNDATA
BIVALVIA
CERASTODERMA PINNULATUM
CRENELLA DECUSSATA
CRENELLA GLANDULA
CRENELLA SP.
HIATELLA SP.
LYONSIA HYALINA
MUSCULUS NIGER
MYA ARENARIA
MYSELLA PLANULATA
MYTILIDAE
NUCULA SP.
NUCULA TENUIS
PECTINIDAE
PERIPLOMA LEANUM
PERIPLOMA SP.
PLACOPECTEN MAGELLAN I CUS
THRACIA MYOPSIS
THYASIRA FLEXUOSA
YOLDIA SAPOTILLA
YOLDIA SP.
BOSTON LIGHTSHIP 1 MEISBURGER 2
HABITAT ! HABITAT
VII 1 VIII 1 V
3.1! 25.0!
12.5! i
! I
I j 50.0
3.1J !
i i
9.4! 8.3',
12.5! !
3.1! 8.3!
I ! 25.0
i i
i i
1 [ 50.0
! 1 125.0
3.1! i
3.1! i
i j
1 j
! 1 25.0
3.1! !
t 1
I i
I 1
1 |
34.4! 58.3! 25.0
12.51 16-7!
9.4! 108.3! 75.0
15.6! 41.7!
! {
i i 25.0
1 ! 25.0
j j
i i
i i
6.3! 33.3! 25.0
9.4{ !
3.1! ! 50.0
! . 1 25.0
21.9! 25.0!
; ]
3.1! 8.3J
i i
! i
6-3{ !
234.4J 350.0J
62.5! 33.3}
40.6J 41.7!
vii ! vin
t
j
8.3;
12.5! 37.5
12.5!
12.5!
4.2J
i
i
i
i
t
i
t
t
8.3!
1 12.5
1
4.2! 25.0
j
!
4.2!
1
1
20. 8 J
!
j
1
37.5! 62.5
4.21 37.5
162.51 62.5
250.0! 175.0
25.0!
37.5[
25.0!
4.2J
8.3J 12.5
16.7!
4.2!
20.81 12.5
i
166.7J 387.5
!
!
j
j
4.2!
208.3! 87.5
16.7J
8.3} 25.0
MEISBURGER 7
HABITAT
V
25.0
12.5
25.0
37.5
12.5
12.5
50.0
12.5
i
VI j VII
I
1
1
1
1
1
1
1
25.0!
t
t
i
i
i
i
i
i
12.5!
i
i
i
i
i
i
i
6.3J 50.0
i
i
i
i
i
i
6.3!
12.5!
1
18.8!
! 25.0
18.8!
6.3{ 125.0
143.8! 75.0
100.0;
93.8! 25.0
25.0!
12. 5j
i
6.3[
i
i
i
i
31.3!
j
i
i
i
i
6.3J
i
i
i
i
i
i
i
(CONTINUED)
-------
TABLE A1-11. (Continued)
GROUP SPECIES
CIRRIPEDIA CIRRIPEDIA
HYS1DACEA HYSIDACEA
CUMACEA CAMPYLASPIS RUBICUNDA
DIASTYLIS ABBREVIATA
DIASTYLIS BISPINOSA
DIASTYLIS SCULPTA
EUDORELLA PUSILLA
PETALOSARSIA DECLIVIS
ISOPCOA EDOTEA TRIL08A
JAERA MARINA
PLEUROGONIUM SPINOSISSIMUM
POLITOLANA CONCHARUM
PTILANTHURA SP.
AMPH1PODA AEGINIHA LONGICORNIS
AHPELISCA MACROCEPHALA
AHPELISCA SP.
AHPHIPOOA
ANONYX LILJEBORGI
ANONYX SARSI
ARGISSA HAMATIPES
BYBLIS SERRATA
CASCO BIGELOUI
COROPHIIDAE
COROPHIUM CRASSICORNE
ERICHTHONIUS FASCIATUS
ERICHTHONIUS SP.
GAHHARUS LAURENCIANUS
GAMMARUS SP.
HAPLOOPS SP.
HAPLOOPS TUBICOLA
HARPINIA PROPINQUA
HIPPOHEDON SERRATUS
JASSA MARMORATA
LEHBOS WEBSTERI
LEPTOCHEIRUS PINGUIS
LYSIAHASSIDAE
HONOCULOOES SP.
MONOCULODES TUBERCULATUS
OEOICEROTIDAE
PHOTIS POLLEX
STENOPLEUSTES SP.
SYRRHOE CRENULATA
UNCIOLA INERMIS
UNCIOLA IRRORATA
UNCIOLA SP.
BOSTON LIGHTSHIP MEISBURGER 2
HABITAT
VII
9.4
15.6
6.3
31.3
3.1
40.6
3.1
43.8
6.3
3.1
18.8
3.1
6.3
6.3
81.3
18.8
6.3
15.6
3.1
6.3
VIII
•
33.3
8.3
8.3
8.3
16.7
175.0
25.0
8.3
108.3
HABITAT
V
75.0
50.0
100.0
400.0
25.0
1250.0
VII | VIII
4.2J
16. 7j 12.5
4.2J
{ 25.0
i
8.3 j
1
1
4.2J
50.0J 75-°
i
i
8.3[
58.3J 112.5
16.7}
8.3! 25.0
i
i
i
i
16.7! 12.5
i
4.2[
i
i
4.2J
i
i
8.3! 162.5
62.5J 150-0
12.5!
4.2J
i
4.2!
212.5J 162.5
8.3! 25.0
12.5J
j
75.0!
62.5J 125.0
4.2! 25.0
i
4.2!
!
4.2J 12.5
4.2J
129.2J
37.5!
MEISBURGER 7
HABITAT
V
12.5
12.5
37.5
50.0
25.0
25.0
25.0
50.0
312.5
so.o! ioo-o!
VI
6.3
6.3
18.8
6.3
12.5
12.5
6.3
56.3
6.3
6.3
12.5
25.0
6.3
VII
25.0
100.0
25.0
125.0
25.0
25.0
25.0
25.0
1618.8',
550.0! 25.0
43.8!
(CONTII
-------
(VBLE A1-11. (Continued)
GROUP SPECIES
PECAPODA CANCER IRRORATUS
[ PAGURUS LONGI CARPUS
SIPUNCULA GOLFINGIA SP.
SIPUNCULA
PHORONIDA PHORONIS ARCHITECTA
BRYOZOA ANGUINELLA PALHATA
f BUGULA TURRITA
CRISIA EBURNEA
ELECTRA PILOSA
EUCRATEA LOR I CAT A
HIPPOTHOA HYALINA
bPHIUROIDEA OPHIOPHOLIS ACULEATA
T OPHIURA ROBUSTA
| OPHIURA SARSI
1 OPHIUROIDEA
KHINOIDEA STRONGYLOCENTROTUS
[ DROEBACHIENSIS
fcHORDATA CHORDATA
ISCIDIACEA APLIDIUM SP.
1 ASCIDIA SP.
1 CORELLA BOREALIS
1 NO. OF INDIV TOTAL
| PORIFERA TOTAL
K HYDROZOA TOTAL
K ANTHOZOA TOTAL
K NEMERTINEA TOTAL
| NEMATODA TOTAL
K ARCHIANNELIDA TOTAL
I POLYCHAETA TOTAL
K OLIGOCHAETA TOTAL
K GASTROPODA TOTAL
| POLYPLACOPHORA TOTAL
K BIVALVIA TOTAL
K CIRRIPEDIA TOTAL
K MYSIDACEA TOTAL
K CUMACEA TOTAL
K ISOPODA TOTAL
K AMPHIPODA TOTAL
K DECAPODA TOTAL
K SIPUNCULA TOTAL
K PHORONIDA TOTAL
K BRYOZOA TOTAL
K OPHIUROIDEA TOTAL
K ECHINOIDEA TOTAL
K CHORDATA TOTAL
BOSTON LIGHTSHIP
HABITAT
VII j VIII
i
i
i
! 8.3
15.6!
34.4J 16-7
i
i P
i ~
i
P i
P !
!
j
62.5[ 33.3
6.3!
i
i
i
i
i
! p
! 8.3
6.3}
9066.5 ! 4732.7
i
p ! P
34.4! 50.0
62.5J 50.0
71.9J
i
i
7947.2} 3433.1
3.1!
31.2! 24.9
i
462.6J 716.6
i
i
9.4[
56.3J
43.7! 41.6
219.1] 349.9
i
15.6! 8.3
34.4} 16-7
P ! P
68.8! 33.3
J
i
MEISBURGER 2
HABITAT
V
25.0
11075.0
75.0
8600.0
200.0
275.0
75.0
50.0
1775.0
25.0
VII ! VIII
i
i
4.2 1
8.3J
258.3J 87.5
P !
j
P !
P !
P J
p ! P
4.2!
4.2!
! 12.5
8.3[
i
4.2J
4.2J
I
I
1
1
4.2!
9534.4} 17925.0
12.5J
P !
116.7J 62.5
137.5J 162.5
91 .7j
45.8!
6863.0] 15675.0
12.5!
33.4J 37.5
1020.9! 862.5
4.2{
16.7J 12.5
16.7J 25-°
116.6! 187.5
746.1J 800.0
4.2J
8.3!
258.3! 87.5
p ! P
16.7{ 12.5
4.2!
i 4.2}
MEISBURGER 7
HABITAT
V j VI ! VII
37.5
4962.5
P
37.5
12.5
•
4137.5
25.0
12.5
150.0
550.0
37.5
6.3!
i
i
i
i
•i
i
12.5J 75.0
i
j
!
!
!
!
!
'
{
!
!
18.8!
i
i
i
i
t
i
i
i
6396.7! 7150.0
i
t
! 150.0
31.3!
31.3!
12.5J
3364.2! 6225.0
25.0!
18.8! 50.0
6.3!
475.4{ 250.0
1
6.3!
{ 25.0
6.3J 125-0
2381.7! 250.0
6.3!
!
12.5! 75-°
i
i
i
i
18.8J
i
i
(CONTINUED)
-------
TABLE A1-11. (Continued)
GROW
X ASCIDIACEA
NO. OF TAXA
SPECIES
TOTAL
ZTOTAL
BOSTON LIGHTSHIP |
HABITAT j
VII j VIII j
6.3} 8.3!
125.0J 76.0J
MEISBURGER 2
HABITAT
V j VII j
! 4.2!
55.0! 150.0J
i
!
vni !
88.0,'
HEISBURGER 7
HABITAT
V [ VI !
i i
61. Oj 92. OJ
VII
45.0
(CONTII
-------
TABLE A1-11. (Continued)
GROUP
NO. OF SAMPLES
PORIFERA
HYDROZOA
ANTHOZOA
NEMERTINEA
NEHATODA
ARCHIANNELIDA
POLYCHAETA
SPECIES
JHEISBUR-
GER 7
HABITAT
TOTAL
SCYPHA CILIATA
CLYTIA GRACILIS
EUDENDRIUM RUGOSUM
EUDENDRIUM SP.
SERTULARIA CUPRESSINA
ANTHOZOA
CERIANTHEOPSIS AMERICANUS
CERIANTHEOPSIS SP.
EDWARDSIA SP.
NEMERTINEA
NEHATODA
ARCHIANNELIDA
AGLAOPHAMUS CIRCINATA
AHPHARETE ACUTIFRONS
AMPHARETE ARCTICA
AHPHARETE SP.
AHPHARETIDAE
AMPHITRITE CIRRATA
ANAITIDES ARENAE
ANAITIDES MACULATA
ANAITIDES MUCOSA
ANOBOTHRUS GRACILIS
APHELOCHAETA MARIONI
APHELOCHAETA MONILARIS
APISTOBRANCHUS TULLBERGI
ARCTEOBIA ANTICOSTIENSIS
ARICIDEA (ACMIRA)
CATHERINAE
ARICIDEA QUADRILOBATA
ASABELLIDES OCULATA
BARANTOLLA AMERICANA
CAPITELLA CAPITATA
CAULLERIELLA CF.
KILLARIENSIS
CHAETOZONE SETOSA
CHONE DUNERI
CIRRATULIDAE
CIRRATULUS CIRRATUS
COSSURA LONGOCIRRATA
DRILONEREIS LONGA
DRILONEREIS MAGNA
ENIPO TORELLI
ETEONE LONGA
VIII
2.0
P
62.5
50.0
25.0
75.0
37.5
12.5
12.5
112.5
12.5|
12.5J
(CONTINUED)
-------
TABLE A1-11. (Continued)
GROUP
POLYCHAETA
SPECIES
EUCHONE ELEGANS
EUCHONE INCOLOR
EUCHONE SP.
EUCLYMENE COLLARIS
EULALIA BILIMEATA
EUSYLLIS SP.
EXOGONE DISPAR
EXOGONE HEBES
EXOGONE SP.
EXOGONE VERUGERA
GALATHOWENIA OCULATA
GATTYANA AMONDSENI
GATTYANA CIRROSA
GLYCERA CAPITATA
GONIADA MACULATA
HARMOTHOE IMBRICATA
HETEROMASTUS FILIFORMIS
LAGISCA EXTENUATA
LAONICE CIRRATA
LAONOME KROYERI
LEITOSCOLOPLOS ACUTUS
LEVINSENIA GRACILIS
LYSILLA LOVENI
MALDANE SARSI
MALDANIDAE
HARENZELLERIA VIRIDIS
MEDIOMASTUS CALIFORNIENSIS
MICROPHTHALMUS ABERRANS
MINUSPIO CIRRIFERA
MONTICELLINA BAPTISTAE
MONTICELLINA
DORSOBRANCHIALIS
MYRIOCHELE HEERI
NEPHTYIDAE
NEPHTYS CAECA
NEPHTYS CILIATA
NEPHTYS INCISA
NEREIS GRAYI
NEREIS SP.
NEREIS ZONATA
NINOE NIGRIPES
OPHELINA ACUMINATA
ORBINIIDAE
OWENIA FUSIFORHIS
MEISBUR-
GER 7
HABITAT
VIII
62.5
125.0
37.5
12.5
237.5
25.0
75.0
62.5
700.0
(CONTI
-------
TABLE A1-11. (Continued)
GROUP
POLYCHAETA
SPECIES
MEISBUR-
GER 7
HABITAT
PARADONEIS LYRA
PARAPIONOSYLLIS
LONGICIRRATA
PECTIHARIA GRANULATA
PHERUSA AFFINIS
PHOLOE MINUTA
PHYLLODOCIDAE
POLYCIRRUS MEDUSA
POLYCIRRUS PHOSPHOREUS
POLYCIRRUS SP.
POLYDORA CAULLERYI
POLYDORA CONCHARUH
POLYDORA CORNUTA
POLYDORA QUADRILOBATA
POLYDORA SOCIALIS
POLYDORA SP.
POLYNOIDAE
PRAXILLELLA PRAETERHISSA
PRAXILLURA ORNATA
PRIONOSPIO STEENSTRUPI
PROTODORVILLEA GASPEENSIS
RHODIKE BITORQUAYA
SABELLIDAE
SCALIBREGMA INFLATUM
SCHISTOHERINGOS CAECA
SCOLETOMA ACICULARUM
SCOLETOHA FRAGILIS
SCOLETOMA HEBES
SCOLOPLOS ARMIGER
SPHAEROSYLLIS SP.
SPIO FILICORHIS
SPIO LIMICOLA
SPIO SETOSA
SPIO "SP.
SPIO THULINI
SPIONIDAE
SPIOPHANES BOHBYX
SPIOPHANES KROYERI
STERNAPSIS SCUTATA
SYLLIDAE
SYLLIS
(TYPOSYLLIS)ALTERNATA
TEREBELLIDAE
TEREBELLIDES ATLANTIS
VIII
25.0
12.5
12.5
237.5
12.5
12.5
(CONTINUED)
-------
TABLE A1-11. (Continued)
POLYCHAETA
OLIGOCHAETA
GASTROPODA
GROUP
POLYPLACOPHORA
BIVALVIA
SPECIES
HABITAT
TEREBELLIDES STROEHI
THARYX ACUTUS
TRICHOBRANCHUS ROSEUS
TROCHOCHAETA HULTISETOSA
TROCHOCHAETA SP.
TYPOSYLLIS SP.
OLIGOCHAETA
ALVANIA EXARATA
BUCCINUM UNDATUM
COLUS PUBESCENS
COLUS SP.
CREPIDULA FORNICATA
GASTROPODA
LACUNA VINCTA
LUNATIA HERDS
MARGARITES HELICINUS
NASSARIUS TRIVITTATUS
OENOPOTA DECUSSATA
RETUSA OBTUSA
TURRIDAE
ISCHNOCHITON ALBUS
ANOMIA SP.
ARCTICA ISLAHDICA
ASTARTE BOREALIS
ASTARTE SP.
ASTARTE UNDATA
BIVALVIA
CERASTODERHA PINNULATUM
CRENELLA DECUSSATA
CRENELLA GLAIJDULA
CRENELLA SP.
HIATELLA SP.
LYONSIA HYALINA
MUSCULUS NIGER
MYA ARENARIA
MYSELLA PLANULATA
HYTILIDAE
NUCULA SP.
NUCULA TENUIS
PECTINIDAE
PERIPLOHA LEANUH
PERIPLOMA SP.
PLACOPECTEN MAGELLANICUS
THRACIA HYOPSIS
MEISBUR
GER 7
VIII
87.5
87.5
50.0
12.5
(CONTl
-------
TABLE A1-11. (Continued)
BIVALVIA
CIRRI RED IA
MYSIDACEA
CUHACEA
ISOPODA
AHPHIPODA
GROUP
SPECIES
JMEISBUR-
GER 7
HABITAT
THYASIRA FLEXUOSA
YOLDIA SAPOTILLA
YOLDIA SP.
CIRRIPEDIA
HYSIDACEA
CAMPYLASPIS RUBICUNOA
DIASTYLIS ABBREVIATA
DIASTYLIS BISPIHOSA
DIASTYLIS SCULPTA
EUDORELLA PUSILLA
PETALOSARSIA DECLIVIS
EDOTEA TRILOBA
JAERA MARINA
PLEUROGONIUH SPINOSISSIMUM
POLITOLANA CONCHARUM
PTILANTHURA SP.
AEGININA LONGICORNIS
AMPELISCA MACROCEPHALA
AMPELISCA SP.
AMPHIPODA
ANONYX LILJEBORGI
ANONYX SARSI
ARGISSA HAMAT1PES
BYBLIS SERRATA
CASCO BIGELOUI
COROPHIIDAE
COROPHIUM CRASSICORNE
ERICHTHONIUS FASCIATUS
ERICHTHONIUS SP.
GAMMARUS LAWRENCIANUS
GAMMARUS SP.
HAPLOOPS SP.
HAPLOOPS TUBICOLA
HARPINIA PROPINQUA
HIPPOMEDON SERRATUS
JASSA MARMORATA
LEMBOS WEBSTERI
LEPTOCHEIRUS PINGUIS
LYSIANASSIDAE
MONOCULODES SP.
MONOCULODES TUBERCULATUS
OEDICEROTIDAE
PHOTIS POLLEX
STENOPLEUSTES SP.
VIII
12.5
12.5
137.5
(CONTINUED)
-------
TABLE A1-11. (Continued)
! GROUP
i
i
i
i
i
SAMPHIPODA
[
i
i
i DECAPOD A
i
i
j SIPUNCULA
j
JPHORONIDA
IBRYOZOA
i
j
t
ioPHIUROIDEA
i
i
t
j
JECHINOIDEA
j
JCHORDATA
JASCIDIACEA
i
i
t
JX NO. OF INDIV
JX PORIFERA
JX HYDROZOA
[X ANTHOZOA
JX NEMERTINEA
|X NEMATODA
JX ARCHIANNELIDA
JX POLYCHAETA
JX OLIGOCHAETA
JX GASTROPODA
JX POLYPUCOPHORA
JX BIVALVIA
JX CIRRIPEDIA
JX HYSIDACEA
JX CUHACEA
JX ISOPODA
JX AHPHIPODA
JX DECAPODA
JX SIPUNCULA
SPECIES
SYRRHOE CRENULATA
UNCIOLA INERMIS
UNCIOU IRRORATA
UNCIOLA SP.
CANCER IRRORATUS
PAGURUS LONGICARPUS
GOLFINGIA SP.
SIPUNCULA
PHORONIS ARCHITECTA
ANGUINELLA PALHATA
BUGULA TURRITA
CRISIA EBURNEA
ELECTRA PILOSA
EUCRATEA LORICATA
' HIPPOTHOA HYALINA
OPHIOPHOLIS ACULEATA
OPHIURA ROBUSTA
OPHIURA SARSI
OPHIUROIDEA
STRONGYLOCENTROTUS
DROEBACHIENSIS
CHORDATA
APLIDIUM SP.
ASCIDIA SP.
CORELU BOREALIS
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
MEISBUR-
GER 7
HABITAT
VIII
12.5
37.5
2512.5
P
62.5
50.0
2037.5
162.5
12.5
150.0
(CONTII
-------
TABLE A1-11. (Continued)
GROUP
X PHORONIDA
X BRYOZOA
X OPHIUROIDEA
X ECHINOIDEA
X CHORDATA
X ASCIDIACEA
NO. OF TAXA
SPECIES
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
TOTAL
ZTOTAL
MEISBUR-
GER 7
HABITAT
VIII
37.5
35.0
^
-------
TABLE Al-12. DOMINANT FISH SPECIES1 AND LOBSTERS IN TRAWLS
CONDUCTED IN AN AREA JUST WEST" OF THE MWRA
PROPOSED OUTFALL BY MASSACHUSETTS DIVISION OF
MARINE FISHERIES, 1991-92.
COMMON NAME
FISH
Ocean pout
LoDghom sculpin
Winter flounder
Atlantic cod
Yellowtail flounder
All other spp.
Total
Total # Indiv.
Trawl length (min)
Total CPUC est. (20 min)
AMERICAN LOBSTER (Count)
Total # Indiv.
Total CPU* esL (20 min)
5/91
5/92
PERCENT COMPOSITION
35
21
19
17
7
1
100%
I
ABUNDANCE
655
20
655
17
17
15
19
33
10
16
7
100%
685
13
1054
60
92
*Those making up > 10% of the catch
bApprox. 42°23' N, 70°49' W ("Rosie's Hole")
'Catch Per Unit
-------
TABLE Al-13. MIXING ZONES FOR DISPOSAL AT IN-CHANNEL LOCATIONS.
SITE
Mystic River
Chelsea River
Inner Confluence
MAXIMUM
LENGTH
(m)
285
300
285
TYPICAL
MAXIMUM
WIDTH
(m)
125
95
80
WORST CASE
AREA
(acres)
8.3
6.4
4.8
MAXIMUM
LENGTH
(m)
480
1190 ,
590
MAXIMUM
WIDTH
(m)
185
140
140
AREA
(acres)
12.5
30.0
14.7
Note: analysis includes effects of simultaneous dredging in the vicinity of disposal operations;
PCB analysis assumes disposal of the Mystic River sediments (worst case for PCBs) in Mystic
- =357
-------
TABLE Al-14. RESULTS OF POLLUTANT TRANSPORT MODELLING FOR
IN-CHANNEL DISPOSAL SITES.
PARAMETER
TSS
Mercury
Copper
Total PCBs
Naphthalene
MAXIMUM 29-DAY
CONCENTRATION
39mg/L
3.2ng/L
5.7ng/L
0.7-1 l.Ong/L3
86ng/L
AMBIENT
CONCENTRATION
0-19 mg/L
4ng/L
300ng/L
7ng/L
04. ng/L
WATER QUALITY
STANDARD1
2
25 ng/L
2900 ng/L
30 ng/L
2,350,000 ng/L4
1 chronic level unless otherwise stated; Co, chronic level = acute level
2 no water quality standard established
3 higher value caused by Mystic River sedunents (25% of total silt to be disposed)
4 actute level, no chronic level established
-------
TABLE Al-15. RESULTS OF POLLUTANT TRANSPORT MODELLING
AT SPECTACLE ISLAND CAD
PARAMETER
TSS
Mercury
Copper
Total PCBs
Naphthalene
MAXIMUM 29-DAY
CONCENTRATION
15 mg/L
0.6ng/L
1.1 ng/L
0.1-0.2 ng/L3
24 ng/L
AMBIENT
CONCENTRATION
4 ng/L
300 ng/L
7 ng/L
0.4 ng/L
WATER QUALITY
STANDARD1
2
25 ng/L
2900 ng/L4
30 ng/L
2,350,000 ng/L4
1 chronic level unless otherwise stated
2 no water quality standard established
3 higher value due to Mystic River sediments (25% of total silt to be disposed)
4 acute level, no chronic level established
-------
TABLE Al-16. SEDIMENT CHARACTERISTICS IN VICINITY OF PROPOSED
SUBAQtJEOUS CONTAINMENT SITES B AND E AND WINTHROP
HARBOR CONTAINMENT SITE.
LOCATION
PARAMETER1
% Silt/Clay
As
Cd
Cr
Cu
Pb
Hg
Ni
Zn
PCBs
% Volatile solids
Oil and grease
Total petroleum hydrocarbon
% Total organic
carbon
SUBAQ Bb
ST1-14
3
3.3
0.6
12.8
10.5
11.6
0.06
162
40.4
TR
1
<100
<100
02
I
ST1-15
5
4.8
1.0
30.7
47.7
32.7
0.22
30.6
81.7
TR
1
600
400
0.3
SUBAQ Ec
B-33-L
—
9
4.9
57
105
62
0.34
18
142
O.05
—
0.40
—
--
1 Results in mg/kg (ppm) unless otherwise noted; all values relative to
dry weight
b Cortell, I990b
e Massport, 1990
d Army Corps of Engineers, (NED) 1992
-------
TABLE Al-17. RESULTS OF POLLUTANT TRANSPORT MODELLING
AT SUBAQUEOUS B.
PARAMETER
TSS
Mercury
Copper
Total PCBs
Naphthalene
MAXIMUM 29-DAY
CONCENTRATION
7mg/L
0.3 ng/L
0.6ng/L
0.06-0.3 ng/L3
12 ng/L
AMBIENT
CONCENTRATION
4 ng/L
300 ng/L
7 ng/L
0.4 ng/L
WATER QUALITY
STANDARD1
—2
25 ng/L
2900 ng/L4
30 ng/L
2,350,000 ng/L4
1 chronic level unless otherwise stated
2 no water quality standard established
3 higher value due to Mystic River sediments (25% of total silt to be disposed)
4 acute level, no chronic level established
-5-4,1
-------
TABLE Al-18. RESULTS OF POLLUTANT TRANSPORT MODELLING
AT SUBAQUEOUS E.
PARAMETER
TSS
Mercury
Copper
Total PCBs
Naphthalene
MAXIMUM 29-DAY
CONCENTRATION
9mg/L
0.3 ng/L
0.7ng/L
0.07-0.3 ng/L3
14 ng/L
AMBIENT
CONCENTRATION
4 ng/L
300 ng/L
•7 ng/L
0.4 ng/L
WATER QUALITY
STANDARD1
2
25 ng/L
2900 ng/L"
30 ng/L
2,350,000 ng/L4
1 chronic level unless otherwise stated
2 no water quality standard established
3 higher value due to Mystic River sediments (25% of total silt to be disposed)
4 acute level, no chronic level established
-------
TABLE Al-19. MAXIMUM CONCENTRATION (mg/1) OF COPPER AND SILT/CLAY IN
THE WATER STRATIFIED COLUMN AT THE BOSTON LIGHT SHIP
DISPOSAL SITE UNDER SUMMER CONDITIONS ESTIMATED BY THE
ADDAM'S MODEL FOUR HOURS AFTER A SINGLE DUMP OF 2,000
CU. YDS.
MAX. CONCENTRATION
OUTSIDE THE MIXING ZONEa
MAX. CONCENTRATION
WITHIN THE MIXING ZONE
DEPTH
(ft)
1
50
108
145
COPPER"
0.00036
0.00035
0.00051
0.00038
SILT/
CLAY*"
5.2
5.5
ME
6.3
COPPER
0.00035
0.00036
0.00066
0.00042
SILT/
CLAY
5.2
5.5
NE
7.9
SILT/CLAY
CLOUD DIA.
(ft)
2738
^Mixing zone = Disposal site boundary
'WQ criteria, Copper = 0.0029 Mg/L
"Background, Copper = 0.00035 Mg/L
'Background, Total Suspended Solids = 4.5 mg/L
dConc. silt/clay = Background TSS (4.5) + concentration on grid
above background
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TABLE Al-20. UTILITIES LOCATED WITHIN TRIBUTARIES PROPOSED
FOR DEEPENING.
UTILITIES
DEPTH (MLW)
MWRA Water Tunnel (McArdle)
NJS. Telephone Cable
Boston Edison Electrical Cable
City of Boston Bridge Cable (McArdle)
City of Boston Fire Alarm Cable
MWRA Water Tunnel (to be removed)
MWRA Sewer Siphon
MWRA Water Tunnel
Boston Gas Siphon
MBTA Electrical Cable
38.5
45.0
40.0
45.0
45.0
35.1
50.8
45.0
40.3
40.0
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TABLE Al-21. AVERAGE CONCENTRATION OF TOTAL ORGANIC CARBON
AND TOTAL PETROLEUM HYDROCARBONS. MASSPORT
DREDGING PROJECT.
SITE
Army Base 1-3
Army Base 4-9
Boston Edison Intake
Conley 11-13
Conley 14-15
Distrigas
Eastern Minerals
Boston Edison Barge Berth
Gulf Oil
Moran
Mystic 2, 49, 50
Mystic Pier 1
North Jetty
Prolerized
Revere Sugar
AVG. CONC. TOC (%)
3.9
2.7
5.4
4.1
3.1
6.6
3.6
10.2
1-7
5.6
2.4
3.7
3.1
5.0
4.5
AVG. CONC. TPH
3233
2390
2851
1310
3127
4393
2425
3650
1820
3035
2175
4640
2627
3970
3000
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TABLE Al-22. COMPARISON OF AVERAGE LEAD AND CHROMIUM
CONCENTRATIONS (MG/L) WITH MASSACHUSETTS
DEP BULK SOn, CONCENTRATIONS (MG/L) FOR
TCLP ANALYSIS. MASSPORT DREDGING PROJECT.
MASS DEP BULK
SOIL LIMIT FOR
CRANDPB
SITE (MG/KG)
Army Base
Boston Edison Intake
Conley
DIstrigas
E. Minerals
Boston Edison Barge
Berth
Gulf Oil
Moran
Mystic Piers
North Jetty
Prolerized
Revere Sugar
100
100
100
100
100
100
100
100
100
100
100
100
AVERAGE BULK EPA REG.
SEDIMENT LEVEL FOR
CONC. (MG/KG) CR & PB
CR PB (MG/L)
146
188
149
242
173
135
100
164
189
151
178
111
103
140
657
221
175
156
350
299
321
476
501
5
5
5
5
5
5
5
5
5
5
5
5
TCLP RESULTS
(MG/L)
CR PB
ND
ND
ND
ND
ND
ND
0.07
ND
ND
ND
0.16
0.33
029
0.41
0.23
0.35
0.17
0.26
0.31
0.46
0.47
0.39
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TABLE Al-23. CONCENTRATION OF SODTCJM AND CHLORIDE FOR
MASSPORT DREDGING PROJECT.
SITE
Conley
Army Base
Moran
North Jetty
Eastern Minerals
Mystic Pier
Gulf Oil
SODIUM (MG/KG)
3250
3600
5930
5560
40140
6560
10650
CHLORIDE
1.9
1.8
2.1
1.8
1.6
2.0
1.1
%
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