vvEPA EPA 542-R-13-009
United States Office of Solid Waste and Emergency Response
Environmental Protection c 0 , , ~ ,
Agency Office of Superfund Remediation and
August 2013
cy Response
lediation and
Technology Innovation
Optimization Review
Naval Base Kitsap OU-1
Key port, Washington
www.epa.gov/superfund/remedytech | www.clu-in.org/optimization | www.epa.gov/superfund/cleanup/postconstruction
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Optimization Review
Naval Base Kitsap OU-1
Keyport, Washington
Report of the Optimization Review
Site Visit Conducted at Naval Base Kitsap on
December 3, 2012
FINAL REPORT
August 2, 2013
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EXECUTIVE SUMMARY
Optimization Background
The U.S. Environmental Protection Agency's definition of optimization is as follows:
"Efforts at any phase of the removal or remedial response to identify and implement
specific actions that improve the effectiveness and cost-efficiency of that phase. Such
actions may also improve the remedy's protectiveness and long-term implementation
which may facilitate progress towards site completion. To identify these opportunities,
regions may use a systematic site review by a team of independent technical experts,
apply techniques or principles from Green Remediation or Triad, or apply other
approaches to identify opportunities for greater efficiency and effectiveness. " 1
An optimization review considers the goals of the remedy, available site data, conceptual site model,
remedy performance, protectiveness, cost-effectiveness and closure strategy. A strong interest in
sustainability has also developed in the private sector and within Federal, State and Municipal
governments. Consistent with this interest, optimization now routinely considers green remediation and
environmental footprint reduction during optimization reviews. An optimization review includes
reviewing site documents, interviewing site stakeholders, potentially visiting the site for one day and
compiling a report that includes recommendations in the following categories:
• Protectiveness
• Cost-effectiveness
• Technical improvement
• Site closure
• Environmental footprint reduction
The recommendations are intended to help the site team identify opportunities for improvements in these
areas. In many cases, further analysis of a recommendation, beyond that provided in this report, may be
needed prior to implementation of the recommendation. Note that the recommendations are based on an
independent review and represent the opinions of the optimization review team. These recommendations
do not constitute requirements for future action, but rather are provided for consideration by the EPA
Region and other site stakeholders. Also note that while the recommendations may provide some details
to consider during implementation, the recommendations are not meant to replace other, more
comprehensive, planning documents such as work plans, sampling plans and quality assurance project
plans.
1 U.S. Environmental Protection Agency. 2012 Memorandum: Transmittal of the National Strategy to Expand
Superfund Optimization Practices from Site Assessment to Site Completion. From: James E. Woolford, Director
Office of Superfund Remediation and Technology Innovation. To: Superfund National Policy Managers (Regions 1
- 10). Office of Solid Waste and Emergency Response (OSWER) 9200.3-75. September 28, 2012.
l
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Site-Specific Background
Naval Base Kitsap Keyport occupies 340 acres (including tidelands) adjacent to the town of Keyport in
Kitsap County, Washington, on a small peninsula in the central portion of Puget Sound. Environmental
cleanup under the Comprehensive Environmental Response, Compensation and Liability Act (or
Superfund) has been divided into two Operable Units (OUs). This optimization review focuses on OU-1,
the former base landfill, which comprises approximately 9 acres in the western part of the base next to a
wetland area and the "tide flats" that flow into Dogfish Bay. A Record of Decision for OU-1 was signed
in September 1998 to address volatile organic compound (VOC) contamination present in groundwater
and polychlorinated biphenyl (PCB) contamination of sediments. The primary components of the selected
remedy included treating VOC hot spots with phytoremediation, removing PCB contaminated sediments
and upgrading portions of the landfill cap. The planting of poplar trees for the phytoremediation remedy
and the removal of the PCB-contaminated sediments occurred in 1999. A portion of the landfill cover was
upgraded in 2003. The U.S. Navy (Navy), EPA, Washington State Department of Ecology (Ecology) and
the Suquamish Tribe generally agree that current levels of VOC contamination in groundwater and
surface water indicate that the phytoremediation remedy is not performing as intended.
Summary of Conceptual Site Model and Key Findings
Chlorinated solvents were released to the environment as a result of historic waste disposal practices at
the landfill. Chlorinated solvents present in the waste, buried marsh layer and possibly underlying
saturated soil continue to impact groundwater in northern and southern portions of the landfill.
Groundwater in the upper aquifer discharges to surface water in the marsh. No sampling points are
present in the intermediate aquifer within the footprint of the landfill, but downgradient sampling points
in the intermediate aquifer demonstrate the chlorinated solvents are present in the intermediate aquifer.
The site team hypothesizes that contamination has migrated in the dissolved phase from the upper aquifer
into the intermediate aquifer through windows in the aquitard located in the central portion of the landfill.
However, the optimization review team believes it might be possible that the contamination in the
intermediate aquifer could be the result of dense non-aqueous phase liquid that historically migrated from
the upper aquifer to the intermediate aquifer in the southern portion of the landfill.
Contaminant concentrations in the upper aquifer in the northern landfill have a clear decreasing trend as
source material and resulting dissolved contamination attenuate. The optimization review team agrees
with the Navy, EPA, Ecology and U.S. Geological Survey that the decreasing concentration trends in
monitoring wells in the northern portion of the landfill indicate that some combination of the
phytoremediation remedy and intrinsic biodegradation are effectively addressing the contamination in the
northern landfill.
Contaminant concentrations in the upper aquifer in portions of the southern landfill (near MW1-4) remain
orders of magnitude above cleanup standards, with seasonal fluctuations and no clear evidence of a
decreasing trend. Contamination appears to be more widespread in the southern landfill than the northern
landfill, but it is unclear how much of the contaminant extent is due to wide-spread source material and
how much is due to contaminant migration in the dissolved phase. Contaminant concentration trends
suggest the potential for significant contaminant mass to be present near or above the water table that
provides an ongoing source of dissolved contamination to groundwater.
Intrinsic biodegradation occurs in both the northern and southern portions of the landfill and is
responsible for reductions in the flux of contamination to surface water. However, the surface water
downgradient of the southern landfill continues to have vinyl chloride concentrations more than an order
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of magnitude above the surface water remediation goal of 2.9 micrograms per liter, indicating that the
phytoremediation remedy and intrinsic biodegradation are not effectively addressing contamination in the
southern landfill area as intended by the 1998 Record of Decision.
Summary of Recommendations
Recommendations are provided to improve remedy effectiveness (protectiveness), provide technical
improvement and assist with accelerating site closure. Specific recommendations for cost reduction and
for environmental footprint reduction (green remediation) were not a primary focus for this optimization
review. The optimization team's recommendations in these areas are as follows:
Improving remedy effectiveness
Continue with efforts to characterize contamination in the southern portion of the landfill to better
understand the extent of the source area. The site team is currently developing a work plan to use passive
soil gas sampling and tree core sampling to conduct this characterization. The optimization review team
supports this approach but offers a more conventional characterization approach for consideration.
Revisit existing data and potentially collect new data to evaluate the vapor intrusion pathway for
buildings across Bradley Road.
Cost effectiveness -
No recommendations are provided in this category.
Technical improvement
Consider testing the use of extracted contaminated water for use in the phytoremediation remedy
irrigation system.
Site closure -
Revisit the surface water remediation goals and points of compliance for the marsh water.
Revisit the groundwater remediation goals.
In addition, the optimization team provides considerations for the following:
• Additional characterization and remediation if initial characterization efforts suggest a relatively
focused source area
• Additional characterization and remediation if initial characterization efforts suggest a relatively
diffuse source area
• Additional characterization and remediation if initial characterization efforts suggest an extensive
source area
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Environmental footprint reduction (green remediation)
No specific recommendations have been provided in this category, but the technical improvement
recommendation to consider testing the use of extracted contaminated water for the phytoremediation
irrigation system could lead to eliminating the use of potable water for phytoremediation irrigation.
IV
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NOTICE AND DISCLAIMER
Work described herein, including preparation of this report, was performed by Tetra Tech GEO (TtGEO)
for the U.S. Environmental Protection Agency under Work Assignment 2-58 of EPA contract EP-W-07-
078 with Tetra Tech EM, Inc., Chicago, Illinois. The report was approved for release as an EPA
document, following the Agency's administrative and expert review process.
This optimization review is an independent study funded by the EPA that focuses on protectiveness, cost-
effectiveness, site closure, technical improvements and green remediation. Detailed consideration of EPA
policy was not part of the scope of work for this review. This report does not impose legally binding
requirements, confer legal rights, impose legal obligations, implement any statutory or regulatory
provisions, or change or substitute for any statutory or regulatory provisions. Mention of trade names or
commercial products does not constitute endorsement or recommendation for use.
Recommendations are based on an independent evaluation of existing site information, represent the
technical views of the optimization review team, and are intended to help the site team identify
opportunities for improvements in the current site remediation strategy. These recommendations do not
constitute requirements for future action, rather they are provided for consideration by the EPA Region
and other site stakeholders.
While certain recommendations may provide specific details to consider during implementation, these are
not meant to supersede other, more comprehensive planning documents such as work plans, sampling
plans and quality assurance project plans (QAPP), nor are they intended to override Applicable or
Relevant and Appropriate Requirements (ARARs). Further analysis of recommendations, including
review of EPA policy may be needed prior to implementation.
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PREFACE
This report was prepared as part of a national strategy to expand Superfund optimization from remedial
investigation to site completion implemented by the EPA Office of Superfund Remediation and
Technology Innovation (OSRTI)2. The project contacts are as follows:
Organization
Key Contact
Contact Information
EPA OSRTI
Kirby Biggs
EPA OSRTI
Technology Innovation and Field Services
Division (TIFSD)
2777 Crystal Dr.
Arlington, VA 22202
b isss. kirb v(S)eo a. gov
phone: 703-823-3081
Ed Gilbert
EPA OSRTI
TIFSD
2777 Crystal Dr.
Arlington, VA 22202
silbert. edwardfSepa.sov
phone: 703-603-8883
Tetra Tech
(Contractor to EPA)
Jody Edwards, P.G.
Tetra Tech
1881 Campus Commons Drive, Suite 200
Reston, VA 20191
iodv.edwards(2),tetratech.com
phone: 802-288-9485
Doug Sutton, PhD,
P.E.
Tetra Tech
2 Paragon Way
Freehold, NJ 07728
dous. sutton(5)tetratech. com
phone: 732-409-0344
2
U.S. Environmental Protection Agency. 2012. Memorandum: Transmittal of the National Strategy to Expand Superfund
Optimization Practices from Site Assessment to Site Completion. From: James. E. Woolford, Director Office of Superfund
Remediation and Technology Innovation. To: Superfund National Policy Managers (Regions 1-10). Office of Solid Waste and
Emergency Response (OSWER) 9200.3-75. September 28, 2012.
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1,1-DCA
1.1-DCE
1,1,1-TCA
1.2-DCA
^gkg
ligIL
ARARs
CERCLA
cis-l,2-DCE
COC
CSM
DNAPL
DPT
EPA
FS
FFS
Ft
HSA
IC
LTM
MCL
mg/kg
msl
MTCA
NAVFAC
NAVFAC EXWC
NBK
OSRTI
OSWER
OU
OU-1
P&T
PCB
PCE
PQL
PUD
QAPP
RAO
LIST OF ACRONYMS
1,1 Dichloroethane
1,1 -Dichloroethene
1,1,1 -Trichloroethane
1,2-Dichloroethane
micrograms per kilogram
micrograms per liter
applicable or relevant and appropriate requirements
Comprehensive Environmental Response, Compensation and Liability Act
cis-1,2-dichloroethene
contaminant of concern
conceptual site model
dense non-aqueous phase liquid
direct-push technology
U.S. Environmental Protection Agency
feasibility study
focused feasibility study
Feet
hollow stem auger
Institutional Control
long term monitoring
maximum contaminant level
milligrams per kilogram
mean sea level
State of Washington Model Toxics Control Act
Naval Facilities Engineering Command
Naval Facilities Engineering and Expeditionary Warfare Center
Naval Base Kitsap
Office of Superfund Remediation and Technology Innovation
Office of Solid Waste and Emergency Response
operable unit
operable unit with former base landfill
pump and treat
polychlorinated biphenyl
tetrachloroethene
practical quantitation level
Public Utility District
Quality Assurance Project Plan
remedial action objective
Vll
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RG
remedial goal
RI
remedial investigation
ROD
Record of Decision
RSE
remedial system evaluation
SVE
soil vapor extraction
TCE
Trichloroethene
TIFSD
Technology Innovation and Field Services Division
trans-l,2-DCE
Trans- 1,2-Dichloroethene
USGS
U.S. Geological Survey
VI
vapor intrusion
VOC
volatile organic compound
WAC
Washington Administration Code
Vlll
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TABLE OF CONTENTS
EXECUTIVE SUMMARY i
NOTICE AND DISCLAIMER v
PREFACE vi
LIST OF ACRONYMS vii
TABLE OF CONTENTS ix
1.0 INTRODUCTION 1
1.1 Purpose 1
1.2 Team Composition 3
1.3 Documents Reviewed 3
1.4 Quality Assurance 4
1.5 Persons Contacted 5
2.0 SITE BACKGROUND 6
2.1 Location 6
2.2 Site History 6
2.3 Potential Human and Ecological Receptors 7
2.4 Existing Data and Information 8
2.4.1 Sources of Contamination 8
2.4.2 Geology Setting and Hydrogeology 8
2.4.3 Groundwater Contamination 10
2.4.4 Soil Contamination 12
2.4.5 Sediment and Surface Water Contamination 12
3.0 DESCRIPTION OF PLANNED OR EXISTING REMEDIES 14
3.1 Remedy and Remedy Components 14
3.1.1 Phytoremediation 14
3.1.2 Sediment Excavation 14
3.1.3 Other Remedy Components 14
3.2 RAOs and Standards 15
3.3 Performance Monitoring Programs 18
4.0 CONCEPTUAL SITE MODEL 19
4.1 CSMOverview 19
4.2 CSM Details and Explanation 20
4.2.1 Vertical Migration of Contamination 21
4.2.2 Shallow On-Going Source of Contamination 21
4.3 Implications for Remedial Strategy 22
4.4 Data Gaps 23
5.0 FINDINGS 24
5.1 Sources 24
5.2 Groundwater 24
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5.3 Sediment 24
5.4 Treatment System Component Performance 24
5.5 Regulatory Compliance 25
5.6 Components or Processes That Account for Majority of Annual Costs 25
5.7 Approximate Environmental Footprint Associated with Remedy 25
5.8 Safety Record 25
6.0 RECOMMENDATIONS ERROR! BOOKMARK NOT DEFINED.
6.1 Recommendations to Improve Effectiveness 26
6.1.1 Characterize Extent of Contamination in the Southern Portion of
the Landfill 26
6.1.2 Review Potential Vapor Intrusion Pathway for Buildings Across
Bradley Road 27
6.2 Recommendations to Reduce Costs 27
6.3 Recommendations for Technical Improvement 27
6.3.1 Consider Using Contaminated Groundwater for the Irrigation
System 27
6.4 Considerations for Gaining Site Close Out 28
6.4.1 Revisit Surface Water Remediation Goals and Points of Compliance
for the Marsh Water 29
6.4.2 Revisit Groundwater Remediation Goals 29
6.4.3 Remedial Considerations if a Targeted Source is Identified 30
6.4.4 Remedial Considerations if a Diffuse Source is Identified 31
6.4.5 Remedial Considerations if Source Removal Efforts are not
Successful or are deemed not Appropriate 31
6.5 Recommendations Related to Environmental Footprint Reductions 32
List of Tables
Table 6-1 Cost Summary Table
Attachments
Attachment A: Figures from Existing Site Reports
Attachment B: Concentration Trend Charts Prepared by the Optimization Review Team
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1.0 INTRODUCTION
1.1 Purpose
During fiscal years 2000 and 2001, independent site optimization reviews called Remediation System
Evaluations (RSEs) were conducted at 20 operating Fund-lead pump and treat (P&T) sites (i.e., those sites
with P&T systems funded and managed by Superfund and the States). Due to the opportunities for system
optimization that arose from those RSEs, the U.S. Environmental Protection Agency Office of Superfund
Remediation and Technology Innovation (OSRTI) has incorporated RSEs into a larger post-construction
completion strategy for Fund-lead remedies as documented in OSWER Directive No. 9283.1-25, Action
Plan for Ground Water Remedy Optimization. Concurrently, the EPA developed and applied the Triad
Approach to optimize site characterization and development of a conceptual site model (CSM). The EPA
has since expanded the definition of optimization to encompass investigation stage optimization using
Triad Approach best management practices, optimization during design and RSEs. The EPA's definition
of optimization is as follows:
"Efforts at any phase of the removal or remedial response to identify and implement specific
actions that improve the effectiveness and cost-efficiency of that phase. Such actions may also
improve the remedy's protectiveness and long-term implementation which may facilitate
progress towards site completion. To identify these opportunities, regions may use a
systematic site review by a team of independent technical experts, apply techniques or
principles from Green Remediation or Triad, or apply other approaches to identify
opportunities for greater efficiency and effectiveness. "3
As stated in the definition, optimization refers to a "systematic site review," indicating that the site as a
whole is often considered in the review. Optimization can be applied to a specific aspect of the remedy
(for example, focus on long-term monitoring [LTM] optimization or focus on one particular operable unit
[OU]), but other site or remedy components are still considered to the degree that they affect the focus of
the optimization. An optimization review considers the goals of the remedy, available site data, CSM,
remedy performance, protectiveness, cost-effectiveness and closure strategy. A strong interest in
sustainability has also developed in the private sector and within Federal, State and Municipal
governments. Consistent with this interest, OSRTI has developed a Green Remediation Primer
(www.cluin.org/greenremediation) and now routinely considers green remediation and environmental
footprint reduction during optimization reviews.
The optimization review includes reviewing site documents, potentially visiting the site for one day and
compiling this report, which includes recommendations in the following categories:
• Protectiveness
• Cost-effectiveness
• Technical improvement
• Site closure
• Environmental footprint reduction
3 U.S. Environmental Protection Agency. 2012. Memorandum: Transmittal of the National Strategy to Expand Superfund
Optimization Practices from Site Assessment to Site Completion. From: James. E. Woolford, Director Office of Superfund
Remediation and Technology Innovation. To: Superfund National Policy Managers (Regions 1-10). Office of Solid Waste and
Emergency Response (OSWER) 9200.3-75. September 28, 2012.
1
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The recommendations are intended to help the site team identify opportunities for improvements in these
areas. In many cases, further analysis of a recommendation, beyond that provided in this report, may be
needed prior to implementation of the recommendation. Note that the recommendations are based on an
independent evaluation and represent the opinions of the optimization review team. These
recommendations do not constitute requirements for future action, but rather are provided for
consideration by the Region and other site stakeholders. Also note that while the recommendations may
provide some details to consider during implementation, the recommendations are not meant to replace
other, more comprehensive, planning documents such as work plans, sampling plans and quality
assurance project plans (QAPP).
The national optimization strategy includes a system for tracking consideration and implementation of
optimization review recommendations and includes a provision for follow-up technical assistance from
the optimization review team as mutually agreed upon by the site management team and EPA OSRTI.
Purpose of Optimization at Naval Base Kitsap Operable Unit (OU-1)
Naval Base Kitsap (NBK) Keyport occupies 340 acres (including tidelands) adjacent to the town of
Keyport in Kitsap County, Washington, on a small peninsula in the central portion of Puget Sound. The
property was acquired by the Navy in 1913, with property acquisition continuing through World War II.
The Navy first used it as a quiet-water range for torpedo testing. During the early 1960s, NBK Keyport's
role was expanded to include manufacturing and fabrication such as welding, metal plating, carpentry and
sheet metal work. Further expansion in 1966 added a new torpedo shop; in 1978, functions broadened to
include various undersea warfare weapons and systems engineering and development activities.
Operations currently include engineering, fabrication, assembly and testing of underwater weapons
systems.
Environmental cleanup under the Comprehensive Environmental Response, Compensation and Liability
Act (CERCLA or Superfund) at the base has been divided in two OUs. This optimization review focuses
on OU-1, the former base landfill, which comprises approximately 9 acres in the western part of the base
next to a wetland area and the "tide" flats that flow into Dogfish Bay. As stated in the OU-1 Record of
Decision (ROD)
"... the OU-1 investigations revealed the potential for risks to occur via three main
pathways: the drinking water pathway, the seafood ingestion (human health) pathway, and
the ecological risk pathway
The two classes of contaminants of concern that were specified in the ROD were polychlorinated
biphenyls (PCBs) and volatile organic compounds (VOCs), specifically chlorinated aliphatic
hydrocarbons. The OU-1 ROD was signed in September 1998 to address VOC contamination of
groundwater and PCB contamination of sediments. The selected remedy included the following
components:
• Treat VOC hot spots in the landfill by phytoremediation using poplar trees.
• Remove PCB-contaminated sediments from around the seep area, which has the highest PCB
concentrations.
• Upgrade the tide gate to protect the landfill from flooding and erosion during extreme tide events.
• Upgrade and maintain the landfill cover.
• Conduct LTM, including phytoremediation monitoring, intrinsic bioremediation monitoring and
risk and compliance monitoring.
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• Take contingent actions for off-base domestic wells, if necessary.
• Implement institutional controls (IC).
The planting of poplar trees, removal of PCB-contaminated sediments and tide gate improvements were
conducted in 1999. A portion of the landfill cover was upgraded in 2003; the other remedial components
are ongoing evaluations or efforts (including various sampling and analysis activities). The U.S. Navy
(Navy), EPA, Washington State Department of Ecology (Ecology) and the Suquamish Tribe generally
agree that current levels of VOC contamination in groundwater and surface water indicate that the
phytoremediation remedy is not performing as intended. As a result, the Navy, EPA, Ecology and the
Suquamish Tribe agreed to work collaboratively to conduct an optimization review of OU-1 to evaluate
potential options for improving remedy performance. This optimization review focuses on OU-1, with
emphasis on addressing the VOC contamination.
1.2 Team Composition
The optimization review team consisted of the following individuals:
Name
Affiliation
Phone
Email
Doug Sutton, PhD, PE
Tetra Tech
732-409-0344
dou2.sutton®,tetratech. com
Peter Rich, PE
Tetra Tech
410-990-4607
Deter. richf5),tetratech. com
The following individuals who are not directly associated with the site also attended site visit and
contributed to the optimization review process:
• Ed Gilbert - EPA OSRTI
• Kirby Biggs - EPA OSRTI
• Tanwir Chaudhry - Consultant, Naval Facilities Engineering and Expeditionary Warfare Center
(NAVFAC EXWC)
• Sarah Rollston - NAVFAC EXWC
• Tom Spriggs - NAVFAC Atlantic
• Bernie Zavala - EPA Region 10
• Kira Lynch - EPA Region 10
1.3 Documents Reviewed
The following documents were reviewed in support of the optimization review:
• Second Five-Year Review (NAVFAC - May 2005)
• Third Five-Year Review (NAVFAC - December 2011)
• Record of Decision (URS Greiner and Science Applications International Corporation -
September 1998)
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Natural Attenuation Evaluation, Operable Unit 1 (URS Group - November 2012)
Remedial Investigation Report (URS Consultants, Inc. and Science Applications International
Corporation - October 1993)
Biodegradation of Chloroethene Compounds in Groundwater at Operable Unit 1, Naval
Undersea Warfare Center, Division Keyport, Washington, 1999-2010 (USGS - 2012)
Annual Report, 2010, Operable Unit 1 (Sealaska Environmental Services, LLC - June 2011)
Annual Report, 2011, Operable Unit 1 (Sealaska Environmental Services, LLC - July 2012)
Phytoremediation Annual Report, 2011, Area 1, Operable Unit 1 (Sealaska Environmental
Services, LLC - May 2012)
Soil Gas Investigation (Tracer Research Corporation - May 1990)
Baseline Risk Assessment Report, Ecological Risk Assessment (URS Consultants, Inc. and
Science Applications International Corporation - October 1993)
Final Focused Feasibility Study for Operable Unit 1 (URS Greiner and Science Applications
International Corporation - November 1997)
Final Summary Data Assessment Report for Operable Unit 1 (URS Greiner and Science
Applications International Corporation - November 1997)
EPA Letter to Captain Mark J. Olson, December 30, 2010
EPA Letter to Mr. Douglas Thelin, Regarding Draft Natural Attenuation Evaluation, Operable
Unit 1, Naval Base Kitsap Keyport, January 26, 2012
Ecology Letter to Mr. Douglas Thelin, March 7, 2012, Regarding Ecology Comments on:
Natural Attenuation Evaluation, Operable Unit 1, prepared by URS Group, Inc. for the U.S. Navy
Kitsap, Keyport, Washington, dated January 26, 2012
Ecology Letter to Mr. Douglas Thelin, March 28, 2012, Regarding Ecology Comments on: Draft
Phytoremediation Annual Report, 2011, Area 1, Operable Unit 1, NBK Keyport, Washington,
Task Order 30, Prepared by Sealaska Environmental for the U.S. Navy Kitsap, Keyport,
Washington, dated 21, March 2012.
1.4 Quality Assurance
This optimization review utilizes existing environmental data to interpret the CSM, evaluate remedy
performance and make recommendations to improve the remedy. The quality of the existing data is
evaluated by the optimization review team prior to using the data for these purposes. The evaluation for
data quality includes a brief review of how the data were collected and managed (where practical, the site
QAPP is considered), the consistency of the data with other site data and the use of the data in the
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optimization review. Data that are of suspect quality were either not used as part of the optimization
review or used with the quality concerns noted. Where appropriate, this report provides recommendations
to improve data quality.
1.5 Persons Contacted
A site visit was conducted on December 3, 2012. In addition to the optimization review team and other
non-site personnel noted above, the following individuals directly associated with the site were present
for the site visit and interviewed as part of the optimization review effort:
Name
Affiliation
Email Address
Aaron Lambert
EPA Region 10
lambert.aaronfSeDa. sov
Milton 'Gene' Clare
Navy Remedial Project Manager - Naval
Facilities Engineering Command
(NAVFAC) Northwest
milton.clarefSinaw.mil
Kwasi Boateng
EPA Region 10
John Blacklaw
Washington State Dept. of Ecology
Denice Taylor
Suquamish Tribe
Richard Dinicola
United States Geological Survey (USGS)
Mike Meyer
URS
Email contact information is provided for the site managers only. Communication with other participants
can be coordinated through the site managers.
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2.0 SITE BACKGROUND
Information in the following sections is generally extracted from the following documents:
• Final Summary Data Assessment Report (URS Greiner and Science Applications International
Corporation - November 1997), subsequently referred to as the "Data Assessment Report";
• Third Five-Year Review (NAVFAC - December 2011), subsequently referred to as the 'Third
Five-Year Review"; and
• 2011 Annual Report (Sealaska Environmental Services, LLC - July 2012), subsequently referred
to as the 2011 Annual Report.
2.1 Location
NBK Keyport occupies 340 acres (including tidelands) adjacent to the town of Keyport in Kitsap County,
Washington, on a small peninsula in the central portion of Puget Sound. NBK Keyport is bordered by
Liberty Bay on the east and north and Port Orchard Inlet on the southeast. Figure 1-1 from the Third Five-
Year Review illustrates the NBK Keyport location (see Attachment A for this figure). The topography of
the site rises gently from the shoreline to an average of 25 to 30 feet (ft) above mean sea level (msl) and
then rises steeply to approximately 130 ft above msl at the southeast corner of the site.
Marine or brackish water bodies on and near the site consist of Liberty Bay, Dogfish Bay, the tide flats, a
marsh and the shallow lagoon. Freshwater bodies include two creeks draining into the marsh pond and
two creeks that discharge into the shallow lagoon. OU-1 consists of Area 1, the former base landfill,
which comprises approximately nine acres in the western part of the base next to a wetland area and the
tidal flats that flow into Dogfish Bay (see Attachment A for Figure 3-1 from the Third Five-Year
Review). Most of the landfill area was formerly a marshland.
2.2 Site History
The Navy acquired the NBK Keyport property in 1913; property acquisition continued through World
War II. The landfill was the primary disposal area for domestic and industrial wastes generated by the
base from the 1930s until 1973, when the landfill was closed. A burn pile for trash and demolition debris
was located at the north end of the landfill from the 1930s to the 1960s. Unburned or partially burned
materials from this pile were buried in the landfill or pushed into the marsh. A trash incinerator was
operated at the north end of the landfill from the 1930s to the 1960s and incinerator ash was discarded in
the landfill. Burning of waste continued at the landfill until the early 1970s.
Various site investigations and assessment studies occurred between 1984 and 1988. A Remedial
Investigation (RI) was conducted at Area 1 between 1988 and 1993, after which human health and
ecological risk assessments were conducted. Based on the results of these studies, seven remedial
alternatives were evaluated in the Feasibility Study (FS) for Area 1, and the Navy, Ecology and EPA
selected a preferred remedial alternative. This preferred alternative was described in the 1994 proposed
plan. Because public comments were not favorable to the preferred remedial alternative, the proposed
plan was withdrawn, and Area 1 was separated from the other areas to become OU-1.
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The Navy, Ecology and EPA conducted further site characterization to collect data to supplement the RI.
Starting in 1995 and ending in September 1996, five quarterly rounds of sampling were conducted. New
data from this site characterization effort were discussed and evaluated in the Data Assessment Report,
which supplemented the RI. A supplemental Focused Feasibility Study (FFS) in 1997 evaluated several
additional alternatives. A new preferred remedial alternative from the FFS was selected and eventually
accepted based on public comments. The OU-1 ROD was executed in September 1998. Remedial actions,
including the planting of poplar trees for a phytoremediation remedy to address VOC contamination,
occurred from late 1998 through 2003. Upgrading of the landfill pavement was the final remedy
construction element to be completed, and it was completed in December 2003.
2.3 Potential Human and Ecological Receptors
Residents and businesses in the town of Keyport use water from two county wells. One of these Public
Utility District (PUD) wells is a backup supply well located just north of the tide flats as shown by well
PUD-2 in Figure 4-2 of the Third Five-Year Review. Water used at NBK Keyport originates from Base
Well No. 5, located on base, just north of the Shallow Lagoon shown in Figure 1-1 of the Third Five-Year
Review. The PUD backup well and the base water supply well are screened in aquifers located about 500
ft below the Clover Park aquitard (see next section). There are two additional thick aquitards that lie
between the Clover Park unit and the screened zones of these supply wells. Both of these wells tap
groundwater that is under flowing artesian conditions.
Homes on the south side of the tide flats and Dogfish Bay and on and near Virginia Point are generally
not connected to public water supply and are instead served by private wells. A well inventory conducted
for the Navy in 1996 and 1997 reportedly found that of the 69 wells in these areas, two-thirds (46 wells)
were identified as being screened in deeper water-bearing zones below or within the Clover Park aquitard.
The inventory categorized the other shallower wells in these areas as follows:
• Fourteen wells tap the upper aquifer. Three of these are used for domestic purposes, five are used
only for non-domestic purposes (for example, irrigation), five are not used (but have not been
abandoned), and the use of one well could not be determined.
• Three wells tap the intermediate aquifer. Two of these are used for domestic purposes and one is
not used (but has not been abandoned).
• Six wells tap either the intermediate aquifer or a water-bearing zone within the Clover Park
aquitard. All of these wells are used for domestic purposes.
Site documents report that the hydrogeology in the vicinity of the tide flats and Dogfish Bay makes it
highly unlikely that groundwater from the landfill would ever flow to off-base areas where it could be
tapped by these wells.
Although not specifically noted in site documents, other potential human receptors could potentially
include occupants of the building across Bradley Road that might be exposed to site-related VOCs via the
vapor intrusion (VI) pathway.
Potential ecological receptors include those in the marsh area, the tide flats and Dogfish Bay. According
to the 1997 FFS Report, there is an ecological risk for not only aquatic organisms in these surface water
bodies, but risk via the food chain, especially the human health risk for seafood ingestion. Because the
site lies within the adjudicated Usual and Accustomed harvest area, the Suquamish Tribe maintains the
right to harvest for ceremonial, subsistence and commercial purposes. PCBs are a main contaminant of
7
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concern (COC) for the ingestion pathway; however, the Third Five-Year Review indicates that no PCBs
have been detected in clam tissue based on sampling and analysis following sediment remediation.
2.4 Existing Data and Information
The following sections summarize information provided in existing documents and do not include
interpretation by the optimization review team.
2.4.1 Sources of Contamination
The landfill was unlined. Waste and ash were disposed in the landfill. Typically the waste was pushed
into the marsh during disposal, and or waste was placed in a burn pile for incineration. Both waste and
ash serve as the sources of contamination. VOC contamination has been detected in both the southern and
northern parts of the landfill indicating potential sources of VOC contamination exist in both parts of the
landfill; however, the 1998 ROD refers to a "hot spot" of VOC contamination in the southern part of the
landfill. This "hot spot" was identified based on the magnitude of VOC contamination in the groundwater
and surface water near the southern portion of the landfill. The 1998 ROD and subsequent U.S.
Geological Survey (USGS) studies indicate the potential presence of dense non-aqueous phase liquid
(DNAPL) and the potential for DNAPL to have caused vertical migration of VOC contamination into the
intermediate aquifer.
As discussed in site documents, the distribution of the PCB contamination, with relatively higher
concentrations in the marsh sediment near the northern portion of the landfill, suggests the predominant
source of PCBs is in the northern portion of the landfill.
2.4.2 Geology Setting and Hydrogeology
Surface Hydrology
The surface topography in the vicinity of the landfill is relatively flat, but steepens to the south, west and
north. Stormwater drainage from the land areas near the OU-1 landfill flows into the marsh located west
and south of the landfill. A small pond ("marsh pond") is located in the central part of the marsh. The
pond is fed by a wetland south and southeast of the pond, two small freshwater creeks that are about 1 to
2 ft wide and stormwater discharge. The pond drains through a small creek ("marsh creek") northward
through a culvert to the tide flats of Dogfish Bay. An existing tide gate was upgraded in 1999 as part of
the remedy to further restrict tidal in-flows to the marsh creek. The tide flats are connected to Dogfish
Bay by a narrow channel through structural fill material that forms the foundation of the Highway 308
causeway and bridge. This channel acts as a constriction to tidal flow and causes the surface water level
in the tide flats to exceed that in Dogfish Bay during outgoing low tides.
Geology and Hydrogeology
The hydrostratigraphy in the vicinity of the landfill is highly heterogeneous. The Data Assessment Report
identifies six general hydrostratigraphic units at the OU-1 landfill. Starting at the ground surface, these
units are as follows with references to how the aquifer is noted in the Data Assessment Report:
8
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Hydrostratigraphic Unit
As Noted on Figures B-3 through B-ll of the Data
Assessment Report
Unsaturated zone
A
Upper aquifer
HI
Middle aquitard
H2 and H3
Intermediate aquifer
H4 and Jo
Clover Park aquitard
Km
Clover Park coarse-grained zone*
See Figure 3 of Data Assessment Report
Additional aquitard*
See Figure 3 of Data Assessment Report
Additional aquifer*
See Figure 3 of Data Assessment Report
Additional aquitard*
See Figure 3 of Data Assessment Report
Additional aquifer*
(screened by PUD well)
See Figure 3 of Data Assessment Report
* Not shown on Figures B-3 through B-ll of the Data Assessment Report
Cross-sections of the hydrostratigraphy are depicted on Figures 3 and B-3 through B-ll of the Data
Assessment Report and are included in Attachment A of this report.
The unconfined upper aquifer is present throughout most of the area. It is generally comprised of sand,
but also includes overlying silt-rich units. The water table intersects the landfill waste material beneath
much of the OU-1 landfill. Roughly 5 to 10 ft of landfill material lies above the water table in the
unsaturated zone, and up to about 5 ft of landfill material lies beneath the water table in the saturated
zone. The middle aquitard that separates the upper and intermediate aquifers is silt-rich in most places,
but is sandy in some locations. This aquitard is also locally absent in the central, eastern and northern
portions of the landfill. Enhanced leakage between the two aquifers is likely to occur at locations where
the middle aquitard is sandy or absent. The confined intermediate aquifer is present throughout the
vicinity of the OU-1 landfill except locally southeast of the landfill and in the northern end. The
intermediate aquifer is generally composed of sand with some gravel and significant silt. In a few places,
silt or till layers separate the intermediate aquifer into upper and lower zones. This aquifer and overlying
middle aquitard extend northwesterly from the landfill underneath the tide flats to Highway 308. The
Clover Park aquitard lies below the intermediate aquifer and is very thick, extensive and fine-grained. In
some locations it contains water-bearing sand and gravel. The continuity of this lower confined zone is
unknown. Logs from deep supply wells, which extend to 500 to 1,000 ft below ground surface, document
three additional thick aquitards beneath the Clover Park aquitard.
Figures 3-13 and 3-24 from the Data Assessment Report illustrate typical groundwater contour maps for
the upper and intermediate aquifers, respectively, in the OU 1 area. The groundwater in the upper aquifer
generally flows through the landfill in a westerly direction, with groundwater discharging into the marsh.
In the southern part of the landfill, the groundwater discharges south or southwest toward the shore of the
marsh. There is a groundwater divide in the upper aquifer east of Bradley Road, where groundwater west
of the divide flows toward the landfill and groundwater east of the divide flows eastward away from the
landfill. Upper aquifer groundwater from the areas south and west of the OU-1 landfill flows toward the
marsh. Most of the groundwater discharges to the marsh where it flows as surface water through the
marsh into the tide flats. The rest of the upper aquifer groundwater (in the northern portion of the landfill)
passes through the landfill to the tide flats rather than the marsh.
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The groundwater in the intermediate aquifer flows beneath the landfill mainly from the southwest,
passing northward through the zone under the landfill and then moving downgradient of the landfill
underneath the tide flats and Dogfish Bay. For the portion of the intermediate aquifer underneath the
northern part of the landfill, the groundwater travels toward the landfill from the west and then also
moves downgradient of the landfill underneath the tide flats and Dogfish Bay. The groundwater contours
for the intermediate aquifer encircle the tide flats, mirroring the topography; this indicates that this
groundwater ultimately discharges into the tide flats and Dogfish Bay. The groundwater levels are
influenced by seasonal and tidal changes, but not enough to change the general flow patterns discussed
above.
Groundwater modeling conducted by the USGS in 1997 supports the conclusion that the intermediate
aquifer groundwater from beneath the landfill discharges to the tide flats and Dogfish Bay. The USGS
modeling report, Ground-water Flow and Potential Contaminant Movement from the Former Base
Landfill at Operable Unit 1, Naval Undersea Warfare Center, Division Keyport, Washington was
prepared during assessment of the supplemental sampling data and is presented in Appendix A of the
Data Assessment Report. The USGS study also concludes that, under present conditions, landfill
contaminants in the groundwater would not flow beneath off-base land areas (where they could be tapped
by domestic wells) before discharging to surface water. The study further concludes that it would be
highly unlikely that even a hypothetical future increase in off-base groundwater withdrawal rates would
alter the intermediate aquifer flow regime in a way that results in landfill contaminants being drawn to
domestic wells.
Hydraulic conductivity determinations, based on slug test measurements, were made for both the upper
and intermediate aquifers during the RI and supplemental data collection program. The Data Assessment
Report indicates an average hydraulic conductivity based on slug tests of the upper and intermediate
aquifers of 4.1 ft per day and 3.3 ft per day, respectively. Based on this information and average hydraulic
gradients, the Data Assessment Report calculates groundwater velocities of approximately 0.15 ft per day
in the upper aquifer and 0.1 ft per day in the intermediate aquifer and travel times along key groundwater
flow paths. The Data Assessment Report calculates the travel time for groundwater to pass through the
landfill in the upper aquifer is on the order of five to eight years, and the travel time for groundwater to
flow from the southern landfill to the tide flats is on the order of 27 years.
Vertical gradients between the upper and intermediate aquifers presented in the Data Assessment Report
indicate that a zone of upward vertical flow exists within the southern and western portions of the landfill,
and a zone of downward flow exists within the northeastern part of the landfill. The vertical gradient is
neutral (approximately zero) in the middle of the landfill where the middle aquitard was found to be
absent.
2.4.3 Groundwater Contamination
VOCs
Figure 6-3 of the Data Assessment Report, which is included in Attachment A of this report, presents the
magnitude (average over five rounds of sampling) and distribution of VOC contamination at various
locations in the upper aquifer prior to the September 1998ROD. VOCs shown in this figure include the
following:
• Trichloroethene (TCE)
• cis-l,2-Dichloroethene (cis-l,2-DCE)
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• trans-l,2-Dichloroethene (trans- 1,2-DCE)
• Vinyl chloride
• 1,1,1-Trichloroethane (1,1,1-TCA)
• 1,1-Dichloroethane (1,1-DCA)
• Chloroethane
• 1,1-Dichloroethene (1,1-DCE)
• 1,2-Dichloroethane (1,2-DCA)
The VOC signature varies by sampling location. For example, at MW1-16 in the southern portion of the
landfill, the VOCs were predominantly 1,1-DCA (50 percent of total presented concentration), cis-1,2-
DCE (20 percent of total presented concentration), vinyl chloride (17 percent of total presented
concentration) and 1,1,1-TCA (7 percent of total presented concentration). However, 100 ft away in the
southern landfill at MW1-04, the VOCs were predominantly TCE (64 percent of total presented
concentration), cis-1,2-DCE (26 percent of total presented concentration) and vinyl chloride (9 percent of
total presented concentration).
Figure 6-3 from the 2011 Annual Report presents TCE, cis- 1,2-DCE and vinyl chloride concentrations in
the upper aquifer from two sampling events conducted in 2011. Table B-l from the 2011 Annual Report
provides the historic VOC data, including the data used in the development of these two figures from the
Data Assessment Report and the 2011 Annual Report.
Several significant features and changes are apparent when reviewing these two figures and the data used
to develop them, including the following:
• VOC contamination is generally present in the southern and northern portions of the landfill and
not in between these two portions of the landfill.
• VOC contamination in the northern portion of the landfill is predominantly TCE and its daughter
products. The total VOC concentrations in the northern portion of the landfill are generally lower
than those in the southern portion of the landfill, and concentrations have decreased over time.
• VOC contamination in the southern portion of the landfill appears to include both 1,1,1-TCA (and
its daughter products) and TCE (and its daughter products), with more 1,1,1-TCA-related
contamination at MW1-16 and more TCE related contamination at MW1-04. Concentrations in
the southern portion of the landfill are generally higher (both historically and at present)
compared to the northern portion of the landfill.
• VOC concentrations atMWl-16 were substantially lower in 2011 thanpre-ROD, even after
including a 1,1-DCA concentration of 1,500 micrograms per liter (|ig/L) detected in MW1-16 in
October 2011 (not shown in the 2011 figure). The most significant decrease occurred around
1999.
• There are seasonal trends in the VOC data at MW1-16, with higher concentrations of VOCs
detected in October compared to July.
• There are seasonal trends in the VOC data at MW1-04, with higher concentrations of VOCs
detected in July compared to October (the opposite pattern of what is observed at MW1-16). The
seasonal high concentrations at MW1-04 are of similar magnitude to the concentrations detected
during the pre-ROD sampling events presented in the 1997 Data Assessment Report.
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VOC contamination is also present in the intermediate aquifer. MW1-25 and MW1-28, located beyond
the downgradient edge of the northern portion of the landfill, are impacted with cis-l,2-DCE and vinyl
chloride. Pre-ROD concentrations of cis-l,2-DCE are illustrated in Figure 13 from the 1997 Keyport Area
Private Well Inventory and Sampling Report (Appendix C of the Data Assessment Report). This figure is
included in Attachment A of this report. Figure 6-5 of the 2010 Annual Report presents TCE, cis-1,2-
DCE and vinyl chloride concentrations for the same two wells during a June 2010 sampling event. The
wells were not sampled in 2011. The pre-ROD and June 2010 concentrations in these two wells are of
similar magnitude. A decrease may be apparent in MW1-25, but a slight increase may be apparent in
MW1-28. Table B-l from the 2011 Annual Report and Table 6-1 of the Third Five-Year Review provide
the historical sampling results for these two wells, but it appears that the pre-ROD data (1995 through
1996) presented in these tables for these two wells are not consistent with the values presented in the Data
Assessment Report, suggesting the potential for data entry or data management errors in these two tables
or in the Data Assessment Report. The detected VOC concentrations in the intermediate aquifer, located
downgradient of the northern portion of the landfill, are currently higher than the detected V OC
concentrations in the upper aquifer beneath the northern landfill. The VOC contamination in the
intermediate zone appears to attenuate prior to MW1-38 and MW1-39; these wells are on the
downgradient side of the tide flats. There are no monitoring wells in the intermediate aquifer within the
footprint of the landfill.
PCBs
Pre-ROD PCB concentrations in groundwater (analyzed as Arochlor concentrations) are depicted in
Figure 30 of the 1997 Keyport Area Private Well Inventory and Sampling Report (Appendix C of the
Data Assessment Report). Groundwater is no longer sampled for PCBs, but sediments, surface water and
fish tissue continue to be sampled for PCBs.
1,4-Dioxane
Groundwater samples were analyzed for 1,4-dioxane one time in 2006. The highest detections were in
MW1-25 and MW1-28 (29 jig/L in both wells). These are intermediate aquifer wells located along Key
Road at the western edge of the northern portion of the landfill. No remediation goal was established for
1,4-dioxane in the ROD, but the current State of Washington Model Toxics Control Act (MTCA) Method
B standard is 4 |ig/L. There were no detections of 1,4-dioxane above a detection limit of 1 |ig/L in the
southern portion of the landfill.
2.4.4 Soil Contamination
Soil data were not reviewed by the optimization review team. It is generally understood that several
organic compounds and inorganic analytes have been detected within the landfill waste. In the case of
VOCs, it is generally understood that this soil contamination is serving as an ongoing source of
groundwater contamination.
2.4.5 Sediment and Surface Water Contamination
VOCs
Surface water sampling locations are illustrated on Figure 4-2 from the Third Five-Year Review. This
figure is provided in Attachment A of this report. TCE and vinyl chloride are routinely detected at surface
water sampling location MA-12 (immediately upstream of the marsh pond) above the remediation goals
of 56 |ig/L for TCE and 2.1 |ig/L for vinyl chloride. Over the past 5 years, TCE concentrations at this
12
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location have ranged from less than 56 |ig/L to as high as 170 |ig/L, and vinyl chloride concentrations at
MA-12 have ranged from less than 2.1 |ig/L to as high as 120 |ig/L. There have been no other VOC
detections above standards in the annual sampling events at any other surface water or seep sampling
location since 2005, and VOCs were never detected above standards at surface water sampling location
DB-14 (Dogfish Bay). Sediments and fish tissue are not sampled for VOCs.
PCBs
PCBs were detected in sediment during the 1996 sampling event, but that impacted sediment was
removed as part of the remedy in 1999. Since that sediment removal, PCBs have not been detected above
the remedial goal of 12 micrograms per kilogram (|ig/kg) in any sediment samples.
Seep location SP1-1, which is believed to have been the primary discharge location of PCBs to the marsh
is sampled every two years for PCBs. Between 2000 and 2004, the total PCB concentration at SP1-1
ranged from 0.42 |ig/L to 0.45 |ig/L, and between 2006 and 2010, the total PCB concentrations at SP1-1
ranged from 0.27 |ig/L to 0.29 |ig/L. In 2010 (and possibly in earlier years), the only detected Arochlor
was 1242 (0.28 |ig/L). The surface water remedial goal for total PCBs is 0.04 |ig/L.
With the exception of one shellfish tissue sample collected in 2000, shellfish tissue sampling results have
been below the remediation goal of 15 |ig/kg wet weight for seafood ingestion.
Other Analvtes
With exception of one chromium exceedance at sampling location MA-11 in 2009 (269 milligrams per
kilogram (mg/kg) compared to a remediation goal of 260 mg/kg), no metals have exceeded sediment
remediation goals at any sampling location during any sampling event. The chromium samples collected
prior to 2009 were well below the remediation goal and did not indicate an increasing trend. Additional
sediment and analysis sampling to further evaluate the chromium exceedance was performed in May
2012. The data were not reviewed by the optimization review team, however, the Navy reports that
chromium detections were less than the State Sediment Quality Standards. It is noted that the sediment
remediation goals provided in the Third Five-Year Review are for marine sediments and that many of the
sampling locations, including MA-11 are likely freshwater and not marine water sediments, which could
have implications for the risk assessment and cleanup standards.
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3.0 DESCRIPTION OF PLANNED OR EXISTING REMEDIES
This section is based on information available from existing site documents. Interpretations included in
this section are generally those presented in the documents from which the information was obtained. The
optimization review team's interpretation of this information and evaluation of remedy components are
presented in Sections 4.0 and 5.0.
3.1 Remedy and Remedy Components
3.1.1 Phytoremediation
Northern and southern areas (plantations) of hybrid poplar trees were planted in accordance with the 1998
ROD to address VOC-contaminated groundwater in the northern and southern portions of the landfill.
According to the Third Five-Year Review and earlier site documents, a planting density was chosen that
would: 1) avoid adverse dewatering of the wetlands adjacent to the landfill, 2) avoid adverse changes in
groundwater flow such as drawing saline water from the marsh pond to the tree stands and 3) maximize
contaminant removal. The hybrid trees were planted in the spring of 1999. A total of 545 trees were
planted in an area between 1 and 1.5 acres in the northern plantation, and 360 trees were planted over an
area of under one acre in the southern plantation. Subsequent tree maintenance and thinning has resulted
in the removal of some trees. Tree spacing is arranged in a grid pattern with approximately 10 ft between
each tree. An irrigation system consisting of an array of shallow buried pipe was installed and is
periodically operated. Fencing was installed around each plantation to prevent unauthorized access.
3.1.2 Sediment Excavation
PCB-contaminated sediment was removed from the marsh creek in 1999. The Third Five-Year Review
states that although the PCB concentrations were below levels requiring active cleanup, this remedial
action was selected to reduce the potential for PCBs to migrate into and accumulate in the tide flats and
Dogfish Bay in harmful quantities in the future. The goal of the sediment removal was to remove
approximately 6 inches of surface sediments where previous sampling had shown the highest PCB
concentrations. A high-pressure vacuum truck with a suction line was used to vacuum the sediment
directly from the marsh into sludge boxes. Approximately 75 tons of sediment was removed from the site
and transported to a Subtitle D landfill for solidification and disposal. The area of the sediment removal is
shown in Figure 1-2 from the 2011 Annual Report (see Attachment A for this figure).
3.1.3 Other Remedy Components
Other remedy components included the following:
• Tide gate upgrade - This remedy component was implemented in 1999 to reduce the tidal
influence on the marsh and to reduce the potential for tidal flow to influence water levels in the
landfill.
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• Landfill cover upgrade - This remedy component was completed between 2002 and 2003 and
included upgrading stormwater facilities and regrading and paving the surface of the landfill not
occupied by the phytoremediation plantations.
• LTM - This remedy component began in 1999 and is discussed further in Section 3.3.
• ICs - According to the Third Five-Year Review, the IC plan is designed to preclude the
installation of wells (except those associated with the remedy) in the vicinity of the landfill and
prevent development or other activity that could disturb the landfill, tide flats or adjoining marsh
and shoreline. These ICs are designed to avoid actions that could lead to unacceptable risks to
human health.
• Contingent remedy - A contingent remedial action plan was finalized in March 2003 and
specifies the actions to be taken if monitoring identifies contamination migrating from OU-1 to
water supply wells. The actions include additional sampling and providing alternate sources of
water to potentially affected properties.
3.2 RAOs and Standards
This section provides a summary of remedial action objectives (RAOs) for various environmental media
affected by site-related contamination as described in the 1998 ROD and the Third Five-Year Review.
RAOs for Soil, Waste and Vapor within the Landfill
• Prevent exposures to humans due to dermal contact with or ingestion of landfill soil or waste
material that contains contaminants that may result in unacceptable risk. For this objective,
unacceptable risk is defined by exposure of humans to concentrations of landfill contaminants
above state cleanup levels for soil (MTCA Method B).
• Prevent exposures to humans due to inhalation of vapor from the landfill that contains
contaminants that may result in unacceptable risk. For this objective, unacceptable risk is defined
by exposure of humans to concentrations of landfill contaminants above state cleanup levels for
air (MTCA Method B).
Section 11.5.3 and subsections of 11.5.3 of the 1998 ROD state that no remediation goals have been
included for soil and vapor because contaminant concentrations in the landfill will not likely be decreased
by the remedial actions or natural processes to a point that allows unrestricted access and unlimited use of
the site.
RAOs for Groundwater
• Prevent exposures to humans due to drinking water ingestion of groundwater that contains
landfill contaminants at concentrations above state and federal drinking water standards and state
cleanup levels for groundwater (MTCA Method B). Section 11.5.3 and subsections of 11.5.3 of
the 1998 ROD state that the points of compliance include the groundwater throughout the landfill
and all groundwater that is suitable as a drinking water resource and that can be affected by the
landfill contaminants. These sections and subsections of the 1998 ROD further state that the need
to take additional action would be based on the contaminant concentration trends observed in the
groundwater monitoring program.
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• Prevent unacceptable risks to humans and aquatic organisms due to migration of landfill
contaminants via groundwater into the adjacent aquatic environments, as defined in the RAOs
discussed below for surface water. Section 11.5.3 and subsections of 11.5.3 of the 1998 ROD
refer to the establishment of alternative or conditional points of compliance in which the point of
compliance is "located within the surface water as close as technically possible to the point or
points where groundwater flows into the surface water." (Washington Administration Code
[WAC] 173-340-720(6)(d)).
The table below summarizes Applicable or Relevant and Appropriate Requirements (ARARS) for
groundwater as presented in the Third Five-Year Review.
Groundwater ARARS for Drinking Water Pathway
Current
Current MTCA
Federal and
Current PQL
Basis of ROD
Method B
State MCL
as Applicable
Chemical
ROD RG (ng/L)
RG
(Hg/L)
(Mg/L)
(Hg/L)
1,1-DCA
800
MTCAB,
drinking water
1600
None
1,2-DCA
5
MCL
0.48
5
1,1-DCE
0.5
PQL
400
7
0.02
1,2-DCE (cis)
70
MCL
80
70
1,2-DCE (trans)
100
MCL
160
100
PCE
5
MCL
0.081
5
1,1,1-TCA
200
MCL
7,200
200
TCE
5
MCL
0.49
5
Vinyl chloride
0.5
PQL
0.029
2
0.02
PCBs
0.04
PQL
0.044
0.5
0.02-0.04
1,4-Dioxane
None
4
None
MCL = Maximum Contaminant Level; PQL = Practical Quantitation Level; RG = Remedial Goal; PCE =
Tetrachloroethene; TCA = trichloroethane; DCA = dichloroethane; DCE = dichloroethene; PCBs =
polychlorinated biphenyl; ng/L = microgram/liter. ROD = Record of Decision; MTCA = Washington Model Toxics
Control Act
RAOs for Surface Water
• Prevent exposures to humans due to ingestion of seafood that contains contaminants at
concentrations that pose unacceptable risk as a result of chemicals migrating from the landfill via
groundwater into the adjacent marine water. For this objective, unacceptable risk is defined by
exposure of seafood resources to concentrations of landfill contaminants in surface water above
state water quality standards, federal water quality criteria and state cleanup levels for surface
water (MTCA Method B). This refers to those surface water criteria and standards developed for
the protection of human health (i.e., seafood ingestion).
• Prevent exposures to aquatic organisms due to contaminants present in surface water at
concentrations that pose unacceptable risk as a result of chemicals migrating from the landfill via
groundwater into the adjacent surface water. For this objective, unacceptable risk is defined by
concentrations in surface water above state water quality standards or federal water quality
criteria developed for the protection of marine organisms.
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The table below summarizes surface water ARARS as presented in the Third Five-Year Review.
ARARs for Surface Water Protection Pathway
ROD RG Based on
Current MTCA
MTCA Method B
Method B Surface
Surface Water
Current NTR
Water Value
Current PQL as
Chemical
(Mg/L)
Organisms Only
(Mg/L)
Applicable (Mg/L)
1,1-DCA
None
None
None
NA
1,2-DCA
59
99
59.4
NA
1,1-DCE
1.9
3.2
23,100
NA
1,2-DCE (cis)
None
None
None
NA
1,2-DCE (trans)
33,000
None
32,817
NA
PCE
4.2
8.85
0.39
NA
1,1,1-TCA
41,700
None
416,666
NA
TCE
56
81
6.7
NA
Vinyl chloride
2.9
525
3.7
NA
PCBs
PQL: 0.04
0.00017
0.00011
0.02-0.04
1,4-Dioxane
None
None
None
MCL = Maximum Contaminant Level, PQL = Practical Quantitation Level, RG = Remedial Goal,, PCE =
Tetrachloroethene, NA = Not applicable; NTR = National Toxics Rule; TCA = trichloroethane; DCA =
dichloroethane; DCE = dichloroethene; PCBs = polychlorinated biphenyl; \xg/L = microgram/liter. ROD = Record
of Decision; MTCA = Washington Model Toxics Control Act.
RAOs for Sediments
• Prevent exposures to humans due to ingestion of seafood that contains contaminants at
concentrations that pose unacceptable risk as a result of chemicals migrating from the landfill via
groundwater into the sediments of the adjacent aquatic systems and then into seafood tissues. For
this objective, unacceptable risk is defined by concentrations in littleneck clam tissues, as defined
in the seafood ingestion RAO discussed below for shellfish.
• Prevent exposures to aquatic organisms due to contaminants present in sediments at
concentrations that pose unacceptable risk as a result of chemicals migrating from the landfill via
groundwater into the adjacent aquatic systems. For this objective, unacceptable risk is defined by
concentrations in sediments above state sediment quality standards (for chemistry) and by
bioassays.
RAOs for Shellfish
• Prevent exposures to humans due to ingestion of seafood that contains contaminants at
concentrations that pose unacceptable risk as a result of chemicals migrating from the landfill
via groundwater into the adjacent aquatic systems. For this objective, unacceptable risk is
defined by concentrations in littleneck clam tissues above a cumulative incremental cancer risk
of 1 x 10'5 or above a noncancer hazard index of 1.0, using exposure assumptions for
subsistence harvesters as identified in Appendix B of the ROD. These target risk levels are
within EPA's acceptable risk range, which refers to an incremental cancer risk range of 10'6 to
10'4 and a noncancer hazard index of 1.0 as acceptable targets for Superfund sites. The risk
levels are also in accord with the risk assessment framework used in MTCA to establish state
cleanup levels for exposures to multiple hazardous substances (WAC 173-340-708). MTCA
does not establish cleanup levels that are specific for shellfish samples.
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• Prevent exposures of aquatic organisms to contaminants migrating from the landfill that pose
unacceptable risk. For this objective, unacceptable risk is defined by concentrations of landfill
contaminants in littleneck clams above the ecological risk-based screening values (i.e., the
maximum acceptable tissue concentrations) in Appendix J of the Summary Data Assessment
Report (U.S. Navy 1997a).
3.3 Performance Monitoring Programs
On-going remedy-related monitoring includes the following LTM programs:
• Monitoring of tree health and nurturing activities such as fertilization, pest control, pruning and
irrigation
• Water level monitoring in January, June, July and October of each year
• Groundwater and surface water quality sampling in June and October of each year
• Sentinel well sampling every two years
• Tide gate inspection and maintenance in January, June, July and October of each year
• Intrinsic bioremediation monitoring conducted by the USGS for VOCs and biodegradation
parameters in up to 14 monitoring wells and nine piezometers in June of each year (for most of
the sampling locations)
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4.0 CONCEPTUAL SITE MODEL
This section discusses the optimization review team's interpretation of existing characterization and
remedy operation data and site visit observations to explain how historic events and site characteristics
have led to current conditions. This CSM may differ from that described in other site documents. CSM
elements discussed are based on data obtained from EPA Region 10 and the Navy and discussed in the
preceding sections of this report.
4.1 CSM Overview
Chlorinated solvents were released to the environment as a result of historic waste disposal practices at
the landfill. Chlorinated solvents present in the waste, buried marsh layer and possibly underlying
saturated soil continue to impact groundwater in northern and southern portions of the landfill.
Groundwater in the upper aquifer discharges to surface water in the marsh. Site documents suggest that
the travel time for groundwater across the landfill is approximately seven years. The groundwater flow
velocities are based on measured hydraulic gradients, assumed effective porosity values and estimates of
hydraulic conductivity based on monitoring well slug tests.
Contaminant concentrations in the upper aquifer in the northern landfill have a clear decreasing trend as
source material and resulting dissolved contamination attenuate. TCE concentrations are generally at or
slightly above the remediation goal of 5 |ig/L. Vinyl chloride (likely due to intrinsic biodegradation of
TCE) is the COC for which the concentration in the northern landfill is highest relative to its remediation
goal of 0.5 |ig/L. Monitoring wells, 1MW-1 and MW1-2, are the two monitoring wells with the highest
concentrations of vinyl chloride in groundwater in the northern landfill. There is an observable,
significant decreasing trend in the vinyl chloride concentration at 1MW-1 (cis-l,2-DCE concentrations
are routinely below standards at 1MW-1) and a significant decreasing trend in the cis-l,2-DCE
concentration at MW1-2 as indicated in Attachment B. The optimization review team agrees with the
Navy, EPA, Ecology and USGS that the decreasing trends at 1MW-1 and MW1-2 indicate that some
combination of the phytoremediation remedy and intrinsic biodegradation are effectively addressing the
contamination in the northern landfill.
Contaminant concentrations in the upper aquifer in portions of the southern landfill (near MW1-4) remain
orders of magnitude above cleanup standards, with seasonal fluctuations and no clear evidence of a
decreasing trend (see chart in Attachment B with log scale for vertical axis). Contamination appears to be
more widespread in the southern landfill than the northern landfill, but it is unclear how much of the
contaminant extent is due to widespread source material and how much is due to dissolved phase
contaminant migration. The different contaminant signatures at MW1-4 and MW1-16 (MW1-16 has 1,1-
DCA, see chart in Attachment B with log scale for vertical axis), suggest the potential of multiple
localized source areas. As discussed in Section 4.2.2, contaminant concentration trends at MW1-4 and
MW1-16 suggest the potential that a significant contaminant mass is present near or above the water table
that provides an ongoing source of dissolved contamination to groundwater. Assuming TCE was the
predominant source of contamination in the vicinity of MW1-4, the relatively high levels of cis-l,2-DCE
and vinyl chloride concentrations compared to TCE concentrations at MW1-4 suggest significant
reductive dechlorination is occurring before contamination reaches MW1-4. Reductive dechlorination
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could be happening in ponded water within the waste layer above the upper aquifer or could be happening
in the upper aquifer upgradient of MW1-4 or both. Water quality in MW1-4 and piezometers
downgradient of MW1-4 show somewhat higher oxidation reduction potential and lower dissolved
organic carbon than other wells in the southern portion of the landfill. Therefore, reductive dechlorination
appears to play a less significant a role in degrading contamination at and downgradient of MW1-4
compared with other locations within OU-1.
Surface water downgradient of the southern landfill at station MA-12 (see chart in Attachment B with log
scale for vertical axis) has consistently vinyl chloride concentrations more than an order of magnitude
above the surface water remediation goal of 2.9 |ig/L, indicating that the phytoremediation remedy and
intrinsic biodegradation are not effectively addressing contamination in the southern landfill area as
expected by the 1998 ROD. The ratios of TCE to cis-l,2-DCE and of TCE to vinyl chloride in surface
water at MA-12 compared to the same ratios at MW1-4 suggest intrinsic biodegradation is occurring in
the upper aquifer prior to discharge to surface water; however, this attenuation is not sufficient to meet the
surface water remediation goals. In addition, the presence of TCE in surface water suggests that the TCE
discharge to surface water is likely along the flow path defined by Pl-10, MW1-4, Pl-9, Pl-7 and pore
water sample locations S-4/S-5.
No sampling points are present in the intermediate aquifer within the footprint of the landfill, but
downgradient sampling points in the intermediate aquifer demonstrate the chlorinated solvents are present
in the intermediate aquifer. The site team hypothesizes that contamination has migrated in the dissolved
phase from the upper aquifer into the intermediate aquifer through "windows" in the aquitard (that is,
areas where the aquitard is not present) in the central portion of the landfill. However, as discussed in
Section 4.2.1, the optimization review team believes it might be possible that the contamination in the
intermediate aquifer could be the result of DNAPL that historically migrated from the upper aquifer to the
intermediate aquifer. Contamination in the intermediate aquifer likely discharges to the tide flats or to
Dog Fish Bay after some degree of dilution from uncontaminated groundwater that converges toward the
area of discharge.
Potential receptors of groundwater contamination considered at the site include users of surface water,
public and potable water supply wells and occupants in the building across Bradley Road that might be
exposed to contaminant vapors via the VI pathway. With respect to surface water receptors, site
documents identify both ecological risks and human health risks through seafood ingestion. Because the
site lies within the adjudicated Usual and Accustomed harvest area, the Suquamish Tribe maintains the
right to harvest for ceremonial, subsistence and commercial purposes. All site stakeholders participating
in the optimization review process agreed that additional work was required to protect the surface water
of the marsh. Water level data, water quality data and geological information have helped identify
contaminant migration pathways and confirm that the public and potable water supply wells are not
affected. The VI pathway was evaluated during the RI with soil vapor sampling and indoor air sampling.
Modular buildings previously located on the landfill were removed. Vapor migration across Bradley Road
was limited with the exception of the area near the intersection of Bradley Road and Torpedo Road. ICs
restrict groundwater use in the area of the landfill and prevent development or activity that could disturb
the landfill.
4.2 CSM Details and Explanation
This section provides additional details and further explanation of key CSM-related review observations.
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4.2.1
Vertical Migration of Contamination
The optimization review team believes it is unlikely that the observed contamination in the intermediate
aquifer results from dissolved contamination migrating vertically from the upper aquifer into the
intermediate aquifer for the following reasons:
• There is a vertically-upward hydraulic gradient between the intermediate and upper aquifers in
the southern portion of the landfill and much of the central portion of the landfill.
• Groundwater in the upper aquifer generally flows from east to west, and the general absence of
upper aquifer groundwater contamination in the central portion of the landfill suggests it is
unlikely that contamination from the southern landfill migrated northward to the window and
then vertically into the underlying intermediate aquifer.
• Although there is a vertically-downward hydraulic gradient between the upper and intermediate
aquifers in the northern portion of the landfill, vinyl chloride concentrations in the intermediate
aquifer at MW1-25 and MW1-28 are higher than those in the upper aquifer under the northern
landfill and have not attenuated as much over time as those in the upper aquifer under the
northern landfill.
An alternative scenario for contaminant transport into the intermediate aquifer is that DNAPL in the
southern portion of the landfill migrated vertically downward from the upper aquifer to the intermediate
aquifer and then the horizontal hydraulic gradient in the intermediate aquifer facilitated the transport of
dissolved contamination toward MW1-25 and MW1-28. This scenario provides a potential pathway and
also explains why cis-l,2-DCE and vinyl chloride concentrations have remained relatively persistent over
time at MW1-28. There is insufficient information to confirm this suggested historic vertical migration
pathway. Regardless, interpreted groundwater flow directions and water quality sampling results in the
intermediate aquifer suggest that TCE is degrading to cis-l,2-DCE and vinyl chloride and that the
intermediate aquifer plume is delineated and discharging to: 1) the tide flats after being diluted (to some
unknown degree) by uncontaminated groundwater converging toward the tide flats from other directions,
or 2) Dog Fish bay after being diluted to the concentrations observed at monitoring wells MW1-36
through MW1-39. Current surface water sampling of these water bodies suggests no exceedances of site
surface water standards; therefore, the optimization review team concludes that additional investigation of
the source and intermediate aquifer plume are not warranted.
4.2.2 Shallow On-Going Source of Contamination
At MW1-4, peak concentrations occur during the June sampling events. The peak TCE concentrations at
MW1-4 are as high as 32,000 |ig/L and are typically a factor of 4 to 10 times higher than the lower
concentrations detected in the October sampling events. The cis-l,2-DCE concentrations are
approximately a factor of 2 times lower and exhibit the same seasonal pattern. The vinyl chloride
concentrations are 30 to 50 times lower than the TCE concentrations and also exhibit the same seasonal
pattern. This seasonal fluctuation is not readily explained from dilution caused by faster groundwater flow
during one season versus another season because the hydraulic gradient and groundwater flow pattern
remain relatively consistent over the year. One CSM interpretation is that precipitation infiltrates during
the rainy season (late fall through spring) and the infiltrated water leaches through solvent-contaminated
waste, accumulates in depressions on top of the silt layer that overlies the upper aquifer and slowly
leaches into the upper aquifer resulting in high concentrations that are still observable during June
sampling events. During the growing season, the poplar trees extract the contaminated water
accumulating above the silt and deplete it such that there is substantially lower mass flux during summer
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and early fall, resulting in lower groundwater concentrations during the October sampling event. This
CSM interpretation would suggest that the phytoremediation remedy is relatively effective during the
growing season. The site team's need to irrigate the plantations suggests further that the poplar trees are
preferentially extracting this shallow (perhaps perched) water that has accumulated over several months
rather than tapping the upper aquifer. The argument for perched water is also supported by TCE to cis-
1,2-DCE to vinyl chloride ratios that suggest significant reductive dechlorination prior to contamination
reaching MW1-4. A second CSM interpretation is that reductive dechlorination is occurring to some
degree in perched water before it leaches into the upper aquifer. Although the above discussion is focused
on precipitation, it is also possible that seasonal changes in groundwater elevation may also play a role in
leaching contamination from the overlying waste to the upper aquifer. If this is the case, the changes in
contaminant concentrations could result from a high water table in the Spring contacting solvent-
contaminated waste and causing groundwater contamination that is observable in the June sampling
event. Under this CSM hypothesis, the phytoremediation remedy would not necessarily be effective.
At MW1-16, concentrations decreased sharply after remedy construction in 1999 and have exhibited a
seasonal trend since that time with the higher concentrations detected in October sampling events
compared to June sampling events. The optimization review team does not offer a conceptual model
hypothesis for this behavior other than it is apparent that changes in the land surface (resulting in more
infiltration) significantly changed the contaminant distribution near MW1-16. Water from irrigation may
also play a role if irrigation water is present near a source of contamination.
4.3 Implications for Remedial Strategy
The above-described CSM has the following potential implications for a remedial strategy:
• If the actual average hydraulic conductivity of the upper aquifer is higher than suggested in
existing site documents, groundwater transport times may be faster than previously thought, and
changes in groundwater and surface water concentrations may respond more rapidly to
remediation than previously thought.
• If density-driven DNAPL flow is the mechanism for contaminant migration from the upper to the
intermediate aquifer, then it is likely that the cis-l,2-DCE and vinyl chloride at MW1-25 and
MW1-28 may persist for many years.
• If the primary mass flux of contamination to upper aquifer groundwater (and hence to surface
water) continues to be from a well-understood, targeted area of the overlying waste, then source
area hot spot remediation may be relatively more straightforward than if the primary mass flux of
contamination was smeared throughout the saturated zone and continues to reside in saturated
silts and clays.
• Vinyl chloride concentrations at surface water monitoring location MA-12, situated in Marsh
Creek prior to entering the pond, are approximately 18 to 30 times the remediation goal, and mass
flux will need to be reduced 95 to 97 percent for the remedy to comply with the surface water
remediation goal for vinyl chloride.
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4.4 Data Gaps
The primary data gap is the horizontal and vertical extent of the contaminant source in the southern
portion of the landfill as it pertains to ongoing contamination of the upper aquifer and potentially ongoing
contamination in the intermediate aquifer.
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5.0 FINDINGS
This section presents the observations and interpretations of the optimization review team. These are not
intended to imply a deficiency in the work of the remedy design or site managers, but rather are offered as
constructive suggestions in the best interest of the EPA, the Navy, Ecology, the Suquamish Tribe and the
general public. These observations have the benefit of being formulated based on operational data
unavailable to the original design team. Furthermore, it is likely that site conditions and general
knowledge of groundwater remediation have changed over time.
5.1 Sources
Please refer to Section 4.0 for a discussion regarding the remaining source of contamination and
associated data gaps. The source area is not well characterized, and this is of particular interest in the
southern portion of the landfill.
5.2 Groundwater
Please refer to Section 4.0 for a discussion regarding the remaining source of contamination and
associated data gaps. Contaminated groundwater continues to discharge to the surface water in the marsh,
resulting in surface water concentrations that are above remedial goals.
5.3 Sediment
Sediment PCB contamination was addressed in 1999 and does not appear to merit further study beyond
the current monitoring program, which consistently shows that PCBs are not detected above standards in
sediments. PCBs continue to discharge from seep SP1-1, resulting in surface water PCB concentrations
above surface water protection standards. Continued monitoring of the seep and sediments is merited. A
single recent exceedance of chromium was detected in sediment, which may merit continued monitoring
of sediments in this location to determine if the chromium detection was a one-time event or if an
increasing trend becomes apparent.
5.4 Treatment System Component Performance
The performance of the phytoremediation plantations is difficult to evaluate because groundwater
extraction and mass removal cannot be easily quantified. The water quality data suggest that the
combination of phytoremediation and intrinsic biodegradation are generally effective at addressing
contamination in the northern plantation relative to remediation goals and that the source in this area is
attenuating over time. By contrast, the water quality data suggest that the combination of
phytoremediation and intrinsic biodegradation are not effective at meeting the remediation goals in the
southern plantation and that the source is not appreciably attenuating over time.
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5.5 Regulatory Compliance
Remedy performance is described above. The current remedy is not operating under a discharge permit or
an air permit.
5.6 Components or Processes That Account for Majority of Annual
Costs
Costs were not discussed as a part of this evaluation. At the request of the stakeholders, the focus is on
evaluating remedy effectiveness and a cost-effective approach to site closure, and current costs are not
material to these optimization objectives.
5.7 Approximate Environmental Footprint Associated with Remedy
The environmental footprint of the existing remedy is very low compared to many other remedies
evaluated in this optimization program. The environmental footprint at this site is generally associated
with personnel travel, laboratory analysis and direct potable water use for irrigation.
5.8 Safety Record
The site team did not report any safety concerns or incidents.
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6.0 RECOMMENDATIONS
This section provides recommendations related to remedy effectiveness and site closure strategy. While
the recommendations provide some details to consider during implementation, the recommendations are
not meant to replace other, more comprehensive, planning documents such as work plans, sampling plans
and QAPPs.
Cost estimates provided in this section have levels of certainty comparable to those typically prepared for
CERCLA FS reports (-30 to 50 + percent), and these cost estimates have been prepared in a manner
generally consistent with EPA 540-R-00-002, A Guide to Developing and Documenting Cost Estimates
During the Feasibility Study, July, 2000. The costs presented do not include potential costs associated
with community or public relations activities that may be conducted prior to field activities. Table 6-1
summarizes the costs of these recommendations. Quantification and evaluation of the remedy footprint
has been deferred until more information is available about the nature and extent of the source area in the
southern portion of the landfill.
6.1 Recommendations to Improve Effectiveness
6.1.1 Characterize Extent of Contamination in the Southern Portion of the
Landfill
The primary data gap to address prior to determining a path forward for site remediation is further
characterization of the source material within the southern portion of the landfill. At the time of the
optimization review site visit, the site team was preparing to conduct a characterization event in which
tree core samples, in-plant sorbent samples and soil gas samples will be collected throughout the southern
portion of the landfill. This information should help provide the site team with an understanding of the
areal extent of contamination.
The root zone of the poplar trees is uncertain. The lack of an influence of the trees on the upper aquifer
potentiometric surface map, and the use of irrigation suggest that the roots likely extract water from the
top soil, waste and underlying silt but perhaps not significantly from the upper aquifer. If this is the case,
then the tree samples (core and in-plant sorbent samples) and soil gas samples may be very effective at
focusing on source material rather than a broader dissolved plume. However, if this is not the case, then
the tree samples may not accurately represent source material that is present within the upper aquifer
below the tree root zone.
The Navy communicated that the cost for the above-described characterization event is approximately
$140,000 and that funding limitations and the need to collect tree core samples during a growing season
will defer this effort until Spring/Summer 2014. An alternate option would be to take a more traditional
approach to characterization by collecting groundwater samples from temporary well points, collecting
passive soil gas samples and evaluating this new data alongside existing monitoring well data. One
potential approach would be to collect passive soil gas samples on a 20-ft by 20-ft grid in the southern
portion of the landfill (approximately 100 samples), evaluate the results and then collect soil and
groundwater samples from approximately 20 to 25 locations based on the soil gas results. The soil and
groundwater sample analytical results would be used to help interpret the soil gas sample results, provide
information about contaminant mass in the saturated zone and determine the general extent and location
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of the source area. As a reasonable worst-case scenario, it is assumed that samples are collected using a
hollow stem auger (HSA) with a soil sample collected from the top of the silt underlying the waste and
the groundwater sample collected from a temporary well point in the upper aquifer. The optimization
review team estimates that this approach would cost approximately the same amount as the tree core/soil
gas sampling plan proposed by the site team (that is, $140,000), including planning, field work, oversight,
laboratory analysis and reporting. Costs would decrease or the number of data points could increase if
direct-push technology (DPT) sampling methods can be used in place of a HSA. If there are concerns
about the limitations of using DPT or HSA rigs drilling into landfill debris, the site team might consider
using a mini sonic drill rig to help overcome these issues. The data obtained from this more traditional
characterization approach would be sparser than the data obtained from the tree core/soil gas sampling
approach, but would provide direct information regarding soil and groundwater concentrations and would
not be subject to the uncertainties associated with the tree core/soil gas sampling approach. Furthermore,
the event can be conducted any time during the year, while tree core sampling must wait until the
Spring/Summer 2014 growing season.
The optimization review team suggests conducting one of the above characterization events and
evaluating the data before conducting further characterization efforts. If this phase of characterization
suggests a focused source area, then source removal will likely be practical and additional
characterization will be merited. However, if the results suggest the source is broad in extent, then source
control rather than source removal may be more likely, and the goal of follow-up characterization would
focus on understanding the exact distribution of the source material.
6.1.2 Review Potential Vapor Intrusion Pathway for Buildings Across
Bradley Road
The soil vapor data presented in the RI suggest contaminant vapors generally did not migrate across
Bradley Road except at the intersection of Bradley Road and Torpedo Road. The optimization review
team recommends that the site team review the RI work and the associated data quality to determine if the
findings are adequate to close the VI pathway for the buildings across Bradley Road from Torpedo Road
south to Gadberry Street. For some buildings, particularly near Torpedo Road, a VI evaluation potentially
starting with near slab or sub-slab soil vapor sampling might be appropriate. The cost for an initial
evaluation that includes review of the RI data plus planning, field work and reporting of additional vapor
samples (if needed) might be approximately $20,000 but could likely be performed for less if the work
can be coordinated with other field activities.
6.2 Recommendations to Reduce Costs
No recommendations are provided for this category because the focus of this optimization review is to
evaluate remedy performance and consider potential alternative paths forward to site closure.
6.3 Recommendations for Technical Improvement
6.3.1 Consider Using Contaminated Groundwater for the Irrigation System
The optimization review team agrees with the optimization review team contributors from the Navy that
extracted contaminated groundwater could be used for the irrigation system instead of tap water. This
approach will reduce the net amount of water flowing through the aquifer and will potentially increase the
exposure of the tree roots to contaminated groundwater. If the site team decides to test this approach, the
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optimization review team suggests the site team install a piezometer near the extraction well and conduct
an aquifer test from the well to provide a better understanding of the hydraulic conductivity of the upper
aquifer. The site team might also consider installing a shallow piezometer in the waste to determine the
thickness of a perched water table, if any. The hydraulic conductivity and perched water information
could be key design factors when considering various remedial options. More frequent monitoring and
well gauging of the southern plantation monitoring wells would be merited to evaluate the effect of this
approach.
The effect of using contaminated water in the irrigation system is uncertain, so the optimization review
team is only suggesting this reuse for one or two growing seasons while the site team evaluates
characterization data and conducts a FFS. The optimization review team is not suggesting this change in
irrigation in place of the additional characterization recommended in Section 6.1.1, in place of
considering more robust treatment approaches or as a potential source of delay in addressing the
contamination in the southern portion of the landfill. The optimization review team estimates that
installing the wells (a shallow extraction well, upper aquifer piezometer and piezometer completed in the
waste), conducting a pump test and two extra sampling and well gauging events in the southern portion of
the landfill might cost approximately $30,000 to plan, conduct, evaluate and report.
6.4 Considerations for Gaining Site Close Out
The optimization review team believes it is premature to evaluate remedial options at this site until
additional characterization of the source area has been conducted and the data evaluated. A limited
number of potential remedial options are discussed in this section at the request of the site stakeholders.
The options presented are not intended to be a complete survey of the remedial options available or the
best options available. Rather, they are conservative approaches that should be applicable for the
scenarios described. The optimization review team recommends a more thorough and expanded remedial
options analysis after further characterization has been completed and the CSM has been updated.
The following considerations focus on various steps and paths forward to improve performance of the
remedy to protect the surface water of the marsh adjacent to and immediately downgradient of the
southern portion of the landfill. The following considerations are provided assuming that site stakeholders
agree with and accept the following:
• Groundwater quality within the footprint of the landfill is not expected to be restored to drinking
water quality for several decades.
• Groundwater contamination in the upper aquifer underlying the northern portion of the landfill is
effectively attenuating due to intrinsic biodegradation (and possibly phytoremediation) in a
reasonable time frame such that additional remedial activities are not merited to address
contamination from the northern portion of the landfill.
• Groundwater contamination in the intermediate aquifer appears to be stable, undergoing a degree
of intrinsic reductive dechlorination and discharging to surface water after some degree of
dilution from uncontaminated groundwater that is also flowing toward the tide flats. Given that
surface water sampling results at the tide flats and Dog Fish Bay sampling locations for the past
several years have been below the current MTCA Method B Surface Water Values, it is assumed
that additional remedial activities are not merited to address contamination in the intermediate
aquifer.
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6.4.1 Revisit Surface Water Remediation Goals and Points of Compliance
for the Marsh Water
Before evaluating various remedial strategies for this site, the site team needs to have a clear and common
understanding of the remediation goals. Based on discussions with the site stakeholders and a review of
the site documents, the optimization review team concludes that the primary remediation goals that
require clarification and revisiting are the surface water protection goals as they apply to the marsh water.
The optimization review team suggests discussing and revisiting the point of compliance and the
numerical criteria for TCE and vinyl chloride for this particular surface water feature.
The 1998 ROD established the use of a conditional point of compliance within surface water, and the
recent Final 2012 Natural Attenuation Report suggests extending the point of compliance to the tide gate,
essentially incorporating the marsh system as a remedial component. Discussions during the site visit
suggested that Ecology would not accept this proposal, and the Suquamish Tribe reiterated its rights to
harvest resources from the marsh system. EPA Region 10 also later commented that the naturally
occurring marsh could not be used as a treatment system. Due to the close proximity of the landfill and
waste to the marsh, it likely makes sense to establish and agree upon a point of compliance within surface
water, but the site stakeholders would need to agree on that location. A potential location would include
MA-12 (which currently exceeds the remediation goals). MA-12 provides two benefits as a point of
compliance. First, due to its location, it likely accounts for all potential discharges from the southern
portion of the landfill but is also upgradient of the marsh pond. Second, it has an extensive and consistent
water quality sampling record to compare groundwater quality with surface water quality historically and
in the future. Discussions regarding the point of compliance could take place before or after the additional
characterization work is completed, but need to occur prior to selecting a new or modified remedial
approach.
With respect to numerical criteria, surface water remediation goals for TCE and vinyl chloride are set by
the MTCA Method B for fish ingestion. Based on the site documents reviewed, the optimization review
team could not identify all of the assumptions that were used to derive the MTCA Method B remediation
goal for these contaminants, but recognizes the MTCA Method B for the ingestion pathway specifically
applies to surface water that supports, or has the potential to support, fish. The optimization review team
questions if the currently used remediation goals of 56 jug/L for TCE and 2.9 jig/L for vinyl chloride (or
even revised values using the MTCA Method B equation) are appropriate remediation goals for the marsh
given the assumptions behind MTCA Method B. If they are not appropriate, then it may be appropriate to
discuss new goals with a risk assessor.
Therefore, as part of a FFS (or other process the site team undertakes to modify the remedial approach),
the optimization review team recommends that the site team discuss the above items to achieve consensus
on the interpretation of the remediation goals for surface water protection as they apply to the marsh. The
optimization review team estimates that this recommendation (which would only be a component of a
remedy options analysis or selection approach) may cost the Navy approximately $15,000 for contractor
support.
6.4.2 Revisit Groundwater Remediation Goals
Shallow contaminated groundwater in OU-1 is only present beneath the landfill and discharges
immediately to surface water at the edge of the landfill. The contaminated groundwater in the
intermediate aquifer is present beneath the landfill and discharges to marine waters at some point
offshore. As a result of these and other factors, groundwater in the known area of the plume is very
unlikely to be used as drinking water even if the contamination is addressed. As a result, the optimization
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review team also suggests revisiting the groundwater remediation goals when revisiting the remedial
approach. The optimization review team believes this could be accomplished for under $5,000 if it is
performed in conjunction with the recommendation in Section 6.4.1.
6.4.3 Remedial Considerations if a Targeted Source is Identified
If results from future characterization (using either approach discussed in Section 6.1.1) show high levels
of contamination in a relatively targeted area or areas, then it may be reasonable to conclude that these
targeted areas are source area hot spots that might be appropriately addressed by excavation with off-site
disposal. A next appropriate step would be to better understand the horizontal and vertical mass
distribution in any targeted area(s) to plan excavation of the source material. It would be appropriate to
conduct an additional DPT sampling event in several locations within the targeted area(s) to collect soil
samples from the waste (if the waste layer is conducive to sampling via DPT methods), the silt underlying
the waste, the upper aquifer and potentially the top of the silt underlying the upper aquifer. Limited DPT
sampling might also be conducted in areas where tree core results are difficult to interpret or where
different lines of evidence about contaminant distribution conflict. For example, if a tree core sample and
soil gas sample located near Pl-7 have relatively low concentrations, it may be appropriate to collect DPT
samples from the waste, silt and upper aquifer in this area because the VOC concentrations from water
quality sampling at Pl-7 have been high (for example, 10,000 |ig/L of TCE). The scope of the additional
DPT sampling event would be determined once the tree core and soil gas samples have been interpreted.
The optimization review team suggests that the level of effort might be on the order of five days in the
field and a total cost of $60,000, including planning, DPT rig and operator, field geologist, analytical
costs and reporting. Refusal caused by debris in the landfill may complicate the use of DPT sampling.
Despite this potential risk, it is likely worth mobilizing a DPT rig to attempt soil sampling in the areas of
interest. If refusal occurs on a relatively limited basis, the DPT sampling can continue to be used, but if
refusal becomes problematic, then it might be appropriate to collect samples with a temporary well points
installed with a HSA. This approach would either significantly reduce the number of locations for which
data can be obtained, significantly increase the cost or both. It would also result in more investigation
derived waste that requires off-site disposal.
Assuming the site team is able to refine the majority of the source material in the southern portion of the
landfill to a 30-foot by 30-foot area above the water table (predominantly the waste and the underlying
silt), then excavation and disposal of the waste may cost on the order of $250,000, including planning,
excavation, transport and disposal of hazardous waste, backfill, oversight and reporting. If significant
waste is present below the water table in the upper aquifer, then dewatering or a complementary remedial
technology, such as in situ bioremediation through enhanced reductive dechlorination, would be needed.
Based on the characterization data and excavation results, the site team would need to evaluate potential
remedial options and the potential impacts of these options on the water quality of the marsh. The extent
of the dewatering or applications of additional remedial technologies would depend on the above-
described soil sampling results and the horizontal and vertical extent of contamination below the water
table. If soil sampling results from the silt and clay underlying the upper aquifer suggest vertical
migration of DNAPL is likely responsible for the contamination observed in the intermediate aquifer, the
site team will need to evaluate the practicality of addressing this source material in the intermediate
aquifer. The potentially complex distribution of the contamination between the upper aquifer and
intermediate aquifer, the difficulty of effectively reaching contamination in the silt and clay of the middle
aquitard (if present) with most available technologies and the potential for long-term back diffusion from
silt and clay could make remediation of deeper contamination impractical. This potential impracticability
and the absence of completed exposure pathways to contamination in the intermediate aquifer would
suggest it is reasonable to limit the vertical extent of remedial efforts to the upper aquifer.
30
-------
Continued monitoring of existing groundwater and surface water monitoring locations would help
determine the success of the source removal. Assuming source removal occurs in the vicinity of MW1-4,
based on the distance of MW1-4 and the groundwater velocities calculated in the 1997 Data Assessment
Report, the site team might expect to see improvements in surface water quality in a two to four year time
period. If the average hydraulic conductivity in the area between source removal and surface water is
higher than that reported in site documents, then the initial influence of the source remediation on
contaminant concentrations may be apparent in a shorter time frame with further influence noticeable in
ensuing years.
6.4.4 Remedial Considerations if a Diffuse Source is Identified
If results from the currently planned characterization effort show high levels of contamination over a
relatively broad area or areas, then it may be reasonable to conclude that a remedial approach other than
excavation is appropriate. Limited DPT sampling (on the order of $50,000 in planning, field work,
laboratory analysis and reporting) might be appropriate to ascertain the distribution of the source material
between the waste, the underlying silt and the upper aquifer. As stated in Section 6.4.2, if DPT sampling
is not practical due to refusal, then it might be appropriate to auger through the landfill debris using an
HSA to collect samples from underlying silt and the upper aquifer. Given the CSM discussed in Section
4.0, the optimization review team finds it likely that a majority of the contaminant mass is likely in the
waste layer and might be readily addressed by soil vapor extraction (SVE). If this is the case, the site team
might consider installing SVE trenches or wells throughout the impacted areas. Due to the relatively
shallow waste layer and a permeable surface, the extraction trenches or points will have limited areal
influence and a relatively high density of trenches or points may be needed.
Assuming the contaminant mass is primarily in the waste layer and covers an area greater than 10,000
square ft, a SVE remedy consisting of a network of shallow extraction trenches, a blower and granular
activated carbon off-gas treatment may cost on the order of $350,000 to implement, including planning,
design, construction, three years of operation and monitoring from June through September (driest
months) and reporting. Although costs are generally comparable with the excavation remedy discussed in
Section 6.4.2, this approach would address a broader area of contamination than the excavation remedy.
However, this approach focuses only on source material in the unsaturated waste layer, whereas the
excavation remedy would be able to address targeted areas of source material in the silt and possibly the
upper aquifer.
Similar to the excavation remedy, continued sampling and analysis of existing groundwater and surface
water monitoring locations would help determine the success of the remedy.
If this approach is selected, then shutdown criteria for the system should be established after the first
summer of operation. If extracted mass for a particular summer is less than a given percentage (for
example, five percent) of the mass removed during the first summer, then only incremental benefit is
being realized, and the site team should not operate the system the following summer.
6.4.5 Remedial Considerations if Source Removal Efforts are not
Successful or are deemed not Appropriate
A potential outcome of characterization efforts is an extensive source area with significant contaminant
mass in the silts and clays that underlie the waste layer or upper aquifer. In this case, source material will
not be easily removed by excavation or SVE, and it might be appropriate to contain the contamination
rather than remove the source. Given that the intermediate aquifer plume is stable, it would appear
reasonable to focus the containment effort on the contamination in the upper aquifer. Potential approaches
31
-------
for containment in the upper aquifer in the order of the least to the most costly option include a permeable
reactive barrier, a recirculation system and a P&T system. Each option is briefly discussed below.
• A permeable reactive barrier would likely contain the plume through an enhanced biodegradation
mechanism. Substrates could be applied through emplacement in a trench or periodic injection to
network of wells.
• A recirculation system would provide broad area treatment through a network of injection and
extraction wells. Groundwater would likely be biostimulated or bioaugmented or both before
being reinjected to enhance biodegradation throughout the recirculation zone.
• A P&T system would provide hydraulic containment with extraction from a recovery trench and
ex-situ treatment or disposal of the extracted groundwater. One option for disposal would be to
integrate extracted water into the irrigation system for the phytoremediation remedy. This use
might require no pre-treatment or might result in less stringent treatment goals than other
discharge options.
Because a containment option for this site could operate for a long period, before selecting any of the
above containment options, the following factors should be well understood and considered:
• A well-defined exit strategy that incorporates specific, measurable, attainable, relevant and time-
bound goals
• Mass distribution of the COCs within the source area and dominant mechanisms that govern the
fate and transport of these COCs
• A robust analysis of the remediation time frame
• Aquifer testing and necessary capture zone analysis for the system design
• A bench-scale and or pilot study for selecting the biostimulation and bioaugmentation
amendments, refining the system design and understanding the potential impact of the operation
(including groundwater oxidation-reduction conditions) to the receptors.
After completing the additional source characterization effort, the site team should perform a detailed
analysis of the remediation options, including source treatment alternatives, containment and
enhancement of the phytoremediation remedy.
6.5 Recommendations Related to Environmental Footprint
Reductions
No specific recommendations have been provided in this category, but the technical improvement
recommendation to consider testing the use of extracted contaminated water for the phytoremediation
irrigation system could eliminate the use of potable water for phytoremediation irrigation.
32
-------
Table 6-1. Cost Summary Table
Recommendation
Category
Additional Capital
Cost
Change in Annual
Cost
Change in Life-
Cycle Cost
(30 yrs, 3 percent
discount rate)
6.1.1 CHARACTERIZE
EXTENT OF
CONTAMINATION IN THE
SOUTHERN PORTION OF
THE LANDFILL
Effectiveness
$140,000
$0
$140,000
6.1.2 REVIEW
POTENTIAL VAPOR
INTRUSION PATHWAY
FOR BUILDINGS ACROSS
BRADLEY ROAD
Effectiveness
$20,000
$0
$20,000
6.3.1 CONSIDERING
USING CONTAMINATED
GROUNDWATER FOR THE
IRRIGATION SYSTEM
Technical
Improvement
$30,000
$0
$30,000
6.4.1 REVISIT SURFACE
WATER REMEDIATION
GOALS AND POINTS OF
COMPLIANCE FOR THE
MARSH WATER
Site Closure
$15,000
$0
$15,000
6.4.2 REVISIT SURFACE
WATER REMEDIATION
GOALS
Site Closure
$5,000
$0
$5,000
6.4.2 REMEDIAL
CONSIDERATIONS IF A
TARGETED SOURCE IS
IDENTIFIED
Site Closure
$310,000
$0
$310,000
6.4.3 REMEDIAL
CONSIDERATIONS IF A
DIFFUSE SOURCE IS
IDENTIFIED
Site Closure
$400,000
$0
$400,000
6.4.4 REMEDIAL
CONSIDERATIONS IF
SOURCE REMOVAL
EFFORTS ARE NOT
SUCCESSFUL OR ARE NOT
APPROPRIATE
Site Closure
$250,000
$60,000
$1,426,000
discounted
or
$2,050,000
undiscounted
Please refer to the text of Section 6. Ofor assumptions regarding costs.
33
-------
ATTACHMENT A:
Figures from Existing Site Reports
34
-------
NBK
KEYPORT
LIBERTY
BAY
RESERVAT10
PIER 2
DOGFISH BAY
S.iARSH
PCKD
FORMER
-ANDFILL
PORT ORCHARD
~
0 (000
mn
Seafe m Fssl
I! ^ NAVY
Figure 1-1
NBK Keyport
U.O> llMV I
NBK Keyport Vicinity Map
THIRD FIVE-YEAR REVIEW
-------
Museum
Tide Flats
McKittrick
950
207 L
791
1051
1032
Shallow
Lagoon
Location
of Former
200
Scale in Feet
U.S. NAVY
NBK Keyport
THIRD FIVE-YEAR REVIEW
-------
-Parking Lot 792 -
MA10d ' ®
, NAVYWEtLB®^,"
MA12 P
S-3B0
. /
-¦rf "
5-4SO.
S-5'0
S-5BQ
S-6Q.
VSW-S6
AVI IV)
South Plantation
LEGEND
Notes:
1. MA10 is a historical sampling location, it is not part of the current monitoring program.
2. All passive-diffusion sampler sites and surface water sampling station SW-S6 were sampled as part of
the intrinsic bioremediation monitoring program, not the risk and compliance monitoring program.
3. MW1-33 was sampled as part of the intrinsic bioremediation monitoring program, not the risk and
compliance monitoring program.
O Piezometer (Groundwater Elevations Only)
© Monitoring Well (Groundwater Elevations Only)
i& Monitoring Weil (Groundwater Sampling Only)
Monitoring Well (Groundwater Elevations
and Sampling)
© Water Supply Well in Deep Aquifer
(Groundwater Sampling Only)
<> Surface Water Sampling Station
s Seep Sampling Station
O Sediment Sampling Station
» Sediment and Tissue Sampling Station
® Sediment and Surface Water Sampling Station
O Passive-Diffusion Sampler Site
U.S. NAVY
0 100 200
SCALE IN FEET
Figure 4-2
Risk and Compliance Long-Term Monitoring
Sampling Locations at OU 1
NBK Keyport
THIRD FIVE-YEAR
REVIEW
BKEYPORn&ib-TssksmQBO 8Sl5yr Reviewing 4-2 M-tej
-------
Q'
SUDW86
LEGEND
MW1-22''
MoruBiinj WtfVPWwnaiM1 to
Upper Agtflfer
.jh .'iuw-5
/(W1 V
•<$:A >
¦V
MonRMng W«VPbrom«9f it
IrawmeflBia Aqv'lta
; Dogfish Bay
Wst»r Supply Wal In Dsap Aqvl"
Prt»ne Waist WeU
MW1-30 n. \
MW1-H- >...
//W
br«? Cross Sacflon
-MW1-35
NOTE: Bofli9» antf *efe aBwn «# wed
at eras sectors « rale rod 8 tn tta
•YTPM
•MW1-3T
/*Zid.
•-MW1-M
flX' sane
Scsto in F«tt
Mi
A
. .. /-TM1C
">S8NW ;
WWI-I6--. :i \ ItSsBSW : i
XV ,J.-~ 1.r™ ;t*4g
»tp*s
;'TWU
tMW1-32
..J !'v~.
« V/ - • MW8J-7 i * •.
tSf/ _ To/pwJePM. \
{/j "' \T ==vr—.•..::..v^
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...>
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MWl-34-
/ >X<
!UC(i ,¦
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UW1-1
CT0189
NUWC KEYPORT
KEVPORT, WASHINGTON
PRE-ROD DATA COLLECTiON
Figure B-3
COMPREHENSIVE
LONG-TERM
ENVIRONMENTAL
ACTION NAVY
Location Map for Geologic Cross Sections
CTOISSMRflOUNCSIPGB.SDRW 11/11*7
-------
Upper Middle
PUD Welt Aquifer Aquitard
Intermediate
A«ui!er Landfill
©
nl
3
in
x>
c
73
2
0
1
Q>
£Q
a?
8.
100
200
Clover Park Aquitd^J
Aquifer
^quita o
«V./& #!¥>>&?
300
400
- 500
Aquifer
•lAquitard"
600
700
Aquifer
800
... &
CLEAN
COMPREHENSIVE
LONG-TERM
ENVIRONMENTAL
ACTION NAVY
Figure 3
Generalized Hydrostratigraphy in Vicinity of OU1
CT0189
NUWC KEYPORT
KEYPORT, WASHINGTON
PRE-ROD DATA COUECTfON
41
CToi^MftmjNa&nDRjiG03,osF mm
-------
Litholopic and Hvdrostratigraphlc Classification
Predominantly Sand and/or Gravel (Aquifer)
Sand and/or Gravel with Local Silt (Aquifer)
Mixed Silt/Clay and Sand/Gravel (ou 1 Landfill shown with Hatching)
(Aquifer or Leaky Aquitard)
Silt/Clay with Local Sand/Gravel (Leaky Aquitard)
Predominantly Silt/Clay with Some Local Peat
(Aquitard)
Contacts and Boreholes/Wells
Stratigraphic Contact
Stratigraphic Contact, Where Inferred
or Approximately Located
< Borehole/Well
2^ Water Level (Average for Round A
High and Low Tides)
< Well or Piezometer Screen Location
< Total Depth of Borehole
Stratigraphic Units (see Table 3-2):
A, B, C, Er, Et, Ea, Eg1, Eg2, H1, H2, H3, H4, Jm, Jt,
Jo, Js, Km, Ks
*
CLEAN
Figure B-4
CT01B9
COMPREHENSIVE
k LONG-TERM
Legend for Geologic Cross Sections
NUWC KEYPORT
KEYPORT, WASHINGTON
T ENVIRONMENTAL.
PRE-ROD DATA COLLECTION
ACTION NAVY
CTO!»\B«WQUN05U£S£NO.DSF fimS?
-------
K*
NORTH
SOUTH
Steps'/
Cieek
Bend In
Section
Keys Road
k >nv rs Sl- «1 MIA I J
-------
WEST PrVa»WBl1
(ProBOK);
SsplhorJy,
no liifiobay)
OU 1 LANDFILL
+40 —
TO! 3
¦ W
ily,
St)
*30 —
Send In
Section
DWflSVIW
•fighway
(303)
Uwl -1!
SB228
MWM5 SB1-13 M«"-27
MW1-10
MW1-9
mm.
iltlKm
LOVER PARK UN
Horizontal Scatem Feet
Vsnical Oalitm is Fesl MS.
CTOT89
NUWCKEYPORT
KEYPORT, WASHINGTON
PRE-ROD DATA COLLECTION
figure B-6
Geologic Cross Section l-L'
COMPREHENSIVE
LONG-TERM
ENVIRONMENTAL
ACTION NAVY
CT01»OAfSROUM»XSEC_LO8F 11(11*7
-------
OU 1 LANDFILL.
M'
NORTHWEST
Private
Wen No. 2
no Sthoiogy] 3o9
Bend m
Sedbn
Brownsville
Highway (303]
A iMWl-Zt
MW1-32
Keys
,20 — Navy P2B4-2
WpiS Itmedafi jso-oe KW&4
MW1-40 \ f
MW'r i
BP22-3
1 ' MWl-29
W-8
Marsh
, m Cree*
w
P&4-!
A Ti
gl c Flats
iH2
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to -140RMSL
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Weato-790ft MSL
CLEAN
COMPREHENSIVE
LONG-TERM
ENVIRONMENTAL
ACTION NAVY
Bgure B-7
Geologic Cross Section M4T
CTO189
NUWC KEY PORT
KEYPORT, WASHINGTON
PRE-ROD DATA COlilCr ION
CTOlWOWiBI^JpSC.MOSr unim
-------
Prrvae
WeflNo. 1
fCKCiadefli
NORTHEAST
no lithokxiy)
Bend >n
Section
1MW-5
MWt-22
4"
MNMinCbi
isKmii
^¦ifllS
§»I
-60—
LOVER PARK UNIT
Km!a>d6afeKs)
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Horizontal Scale in Feat
10X Vertical
Vertical Daium is Fee! MSL
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-80—
CLEAN
COMPREHENSIVE
LONG-TERM
ENVIRONMENTAL
ACTION WAVY
Figure 8-8
Geologic Crass Section N-N'
CTOI89
NUWC KEYPORT
KEYPORT, WASHINGTON
PRE-ROD DATA COLLECTION
C70ttW»flW>U«Q5UeSKLN.i»P mt/97
-------
P'
NORTH
OU 1 LANDFILL
SOUTH
Bertdin
Sedwi
SeflJin
Sfefion Keys
MWi*1 ^-Wns^Road
Hch*a*
tprtttcted)
MW1-4
Mmh
MW144
Marsh
WW-25
RM1.9B
2\_^:
fiifcfias
mw»m
-'vH3 - -20
PARK
^ftmssMSsSM
?S(^.i^hXi*WSiSS8
ISllwliSi
CLEAN
COMPREHENSIVE
LONG-TERM
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ACTION NAVY
Figure B-9
Geologic Cross Section P-P*
CTOI89
NUWC KEYPORT
KEYPOflT, WASHINGTON
PRE-ROD DATA COLLECTON
CTO«so«weiH^BR.PiJSf tvnm
-------
orpedo
SOUTH
Bend in
^ S3 22-1D SefW
NORTH
Bradley Road
Highway
306
T TP (to
J SSNW
UW,T-" «^1'i'
MWt-3 J
BOfi *1
ipojeSBijloi
deep contacts)
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_ _ \en
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1MW«
\ SP2?'
nw»a
MW1-23
c» X Z
fct-;.;\ErorD ~
I
I
I
*•13 or Jm
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^wiiml.
mmm
mm
wmmmi
JLOVER PARK UNfr«IIMI
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Km (and Iiltte Ks)
to-210ftMSL
Well to -755 ft MSI 8
—c=*c=§°
Hwljerta) Sca)e in Feel
fOX Vertkai Exaggeraton
Vertical Datum is Feel M&
CLEAN
COMPREHENSIVE
LONG-TERM
ENVIRONMENTAL
Figure B-1Q
Geologic Cross Section Q-Q'
CTO f 89
NUWC KEYPORT
KEYPORT, WASHINGTON
PRE-RQD DATA COLLECTION
ACTION NAVY
CTOUWOASTOUIiDEaSK.QtBF I11W7
-------
Bend «n SecSion
OU 1 LANDFILL
R
Bends in Section
Deep Contacts
Projected Itom
Other Cross Seaion
NORTH
SOUTH
OeepCenlaas Projected
trom Other Cross Sedions
tSO—
TP 85
(projected)
B-8
(projected)
Sst-12
SBMW SBNE
TP
-------
LEGEND
eiomsw o! W9!ai Surface (las sUve Mst-i
Mcndsrtns WelV»isBme»r in Upp«iA®S3>
PiwsiB W»l>rW»« !n Hope! Aotitter
Suftscs Wa»r EBntiion Messiirtno PoM
9? v 1MW-5
\ /&:/ X
' ¦ W .. \
Dogfish Bay
GTOinBusMf Flow HrsaW!
Apcoiimais Outilne ol Fomwt landSS
Waw leva# Measured 9-13-36
s?'
¦ . // Ism
^ / .-T:.».55
f /
Scale in Fe*t
MW'-19. V; '¦
7 76
MWM8
mii-i
9?
* V\
•Cs
Tomeflo Rd
.'PtlVSiB
.• ' ,-y Well 2 .
1.93 4
>" .
MW!-1* { I
SB I i PI 7.7! 6
MW1-2
-Phvaia
¦•" WbIH
4102 jT •• • •" ' f-i
Q " 'TiijhoimR:^ •
SMW-1
HO t
MW22-5
9.36
• -.<0.64
MAH-1S
535
¦ MW1-10
,itr
I 1 'MWt-17
:::]»« / >.
MW1-6
™ ;WWl -3531
...-6.96 \iwf
. h N 1
I'SM » : '?¦
MWI-Svi
„ \ A. i- -\fj" -?•-
1 \:T 6.19 !
* " V "*&*" ^,v,i
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¦<&r MW22-2 :!> ,
"'is : i' *•
-6-ux'/a*
"5 '
wwt-e
.,V>V '
PZ1-3 '
42 56
-MW3-5
' Sf mm
-------
Dogfish Bay
(surface water- +J. 7 h MSI)
LEGEND
-a-
Elevation of PcieflCfwi* Water Surface
((Be! B60V8 MSL), dashed wtiera
appraxunscety ooaas et irtferoo
j
H3ie: Cora out irasmlMtm 1Dtl MSL
Is1 n;MW*»trte¥>10SMSU«2h
Mort»i?ig tVWMeioroisr
in Intsirawata Aq«it»r
6.7S
MaasutafiWalet Etevafcon (l98t Biws MSI)
Groimdwaw FSw D#Kllon
AwwiMWOaillna ®t former taMM
WatsrlevBteMsBSiireOonS-lS-SI
•#>
| 0 200
T
Seals m Faei
MW1-22
6.51
PZ1-5
5
\
\y '
MW1-30
; • : Mirca
MW1-36
569
MW1-37
5.73
MW1-23
MW1-39
57?
MW1-33
V5.66
MW1-24
"MW1-32
3.99
3.93
1MVM
To'peda Ri
MW1-S0
TsgfttiPft;!. /
6
i« i»i
w '>.<
MW1-27
MW1-9
P7 1051
t34i[
0a;Ibnrru si
MWt-7
w)vrw<"?
^
_ i I/')'!.! , /V
Sim
PZ1-4
19.29
Shallow
Li.go.on
/ kvc y
^ 260* south to MW2-2 (17.22)
CLEAN
COMPREHENSIVE
LONG-TERM
ENVIRONMENTAL
ACTION NAVY
Figure 3-24
Water-level Contour Map
Intermediate AquHer < High Tide
Round 5
CTO 185
NUWC KEYPORT
KEYPORT. WASHINGTON
PRE-flOD DATA COLLECTION
croiwjjifffiOUNOSUHsi.a.cw law
-------
r
• MW5
o
MllMOTI
'
None- Zona
TCE Dsugite'*
: v* \
toXai/rtHJ
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V !«:r?V-- "•
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\ •iS
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y ¦ L:
...
TCE Daughters
1,1,1-TCA Daughters
j 5 A MW1-3
!¦;< •¦no
£>. ¦«" :
r' »» :
TaghwrtiVJ.
MWM5
j I] Sit ;
i 507
MW1-10#;
M
MW1-17 \
n £p-87' " \ \ !|
;; \ \; >j#
VSlv°^ iMWl-6 V- V I
: $ MWt-35
LEGEND
...... 'WroimalstMaltono<¦WMow"InAwMsj
Bowwn Upper ana Iraarmwaa AquHsn
4) Mortaring Wen Sto»(^| Sura ol tneiege
MW1-4 OctsetsflCwitMWteiwrtCAHitnfleafldii
19,000 tfraugftStuffU
nd NotDelsctsS
—-10.**
iO-tMUSit
HiM too-i.aniiaT.
1.QOO-tO,®0^1
><0,0C0
; MWt-9 ~f
¦¦ nd ^
k ...
•¦42,000
1.900 ¦
HW1-«i ! i"""IW(
19.000| j
MW1-M
Southern Zone
TCE
TCE Deughteri
1,1,1-TCA
1,1,1-TCA Dajgh'.ers
1,2-OCA
^kagQofii
,&«sxbli4 ,
~
200
\ % 'S !
\ v
:y''
/ I I'M
• .- '¦\'~
,/f ' "N
SCALE IN FEET
CLEAN
COMPREHENSIVE
LONG-TERM
ENVIRONMENTAL
ACTION NAVY
Rgure 6-3
CAM Contaminant Zones In the Upper Aquifer
CT01S9
NUWC KEYPORT
KEYPORT, WASHINGTON
PRE-ROD DATA COLLECTION
CTOI8»Wf«TOJSrS¥KS _105f Mlm
-------
Annual Report. 20] 1 Final
Operable Unit 1 Julv 27. 2012
Contract N44255-O9-D-4O05
L'I"M/0 / Task Order 30
0 100 200
Scale In Fast
SP1-1
July
Oct
TCE
0.5 U
MS
cis-i,2-DCE
0.27 J
NS
VC
0.11 J
MS
North
Plantation
••
- .
Remediation Goals iiig/L)
MW1-2
Analyie
Grmjndwaffir
Surlace Water
July
Oct
* V
TCE
50
56
TCE
3.0
2.3
\
CIS-1.2-DCE
70 0
NE
as-f.J-DCF
440 D
360 D
VC
05
9. S
VC
SOD
67
Mwt-n
Julv
Oct.
TCE
0.5 U
0.5 U
eis-1.2-DCE
0.26 J
0.23 J
VC
0 16 J
01?J
1MW-1
July
Oct.
TCE
0.11 J
0.5 U
cis-i ,2-DCE
37
31
VC
370 D
280 D
/ Marsh
Pond ^
MA12
July
Oct
TCF
100 D
67
CI9-1.2-DCE
670 ~
420 D
VC
91 D
51 D
Monitoring Well rn Upper
Aquifer
H Seep/Surface Water
NE - notestaBiished
yg/l = micrograms per liter
ICE = trichloroethene, yg/L
cis-1,2-DCE =
C]S"1.2"dichloroetf!Gns. pg/L
VC = vinyl chloride, ggtt.
J = estimated result
U = not detected a* va'ue shown
D = the reported result is from a
dilution
NS = not sampied
NOTE
Bold denotes temeditation goal
exceeded. .
MW1-03
July
Oct
TCE
0 5 U
0.5 U
CIS-1.2-DCE
0.5 U
0.5 U
VC
05U
0 5 U
South
Plantation
MW1-06
July
Oct
• •
Ui
0 42 J
04J
CIS-1.2-DCE
06
0 46 J
VC
9.4
3.6
MWM6
Julv
Oct.
TCE
0.39 J
1.4 JO
cis-1.2-DCE
1 6
1,300 D
VC
0.72
360 D
MW1-20
'
July
Oct
TCE
05U
0 5 U
cis-1.?-DCe
0 5 U
05U
VC
0 5 U
0 6 U
:
.¦
.¦
MW1-04
July
Oct.
TCE
22,000 D
390 D
ci9-1,2-DCE'
11,000 D
840 D
VC
440 D
86 D
Figure 6-3
U.S.NAVY
SEALASKA
Distribution of Selected Target VOCs
For Upper Aquifer
Task Order 30
NBK Keypoit
OU 1 Annual Report 2011
July and October 2011
SJ S l\ \'A) I ?
6-10
-------
Dogfish Bay
°4~ •
MW1-22* / ;
/ ^
/&'
t\ : MuMum ¦
¦ <&/
//
AMWi-23 \ \
iwwV-36
mi-v
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Flats
% : .-.i MW1-24
w « :
I • :
McKitEricX Rd
as
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/
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2,S0aj; 2,200j1 47DJ j2,2oM na
t
Toledo Rd.
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MWt-26
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1.7M4 1,400
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LEGEND
+ InisrmeOiaa iauitat UoMioiins W«l
Map Shows AS IrtsrnwdMM Ajjurtar Wsba Ssnpte Owing
Rour*S 1,2,3,4, araVor S. Ai DMKttont are Sfswnas Follows:
-5iat»fi
• 3 \> ,*
§ \ Vr
;• i ! HKtf
<-~- MW1-7 \\ • S
> '..I- v.v y '¦¦' ' '¦ V ;¦¦•¦— >
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Cure, dataasd Round
i \n
.-to-.. 'ii
s-',>;
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4h
SCO
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i../ '°~
\
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,-/vx.
/ : x s
1
'V'
Scale in Fee!
Ddnklrio Wa&i
70
Surface Waiar
...
ieafeetui)
Surface Wala
32.600
(Human Health)
CLEAN
COMPREHENSIVE
LONG-TERM
ENVIRONMENTAL
ACTION NAVY
Figure 13
Distribution of cis-1,2-Dichloraethene
in intermediate Aquifer
CTOI89
NUWC KEYPQRT CHJ 1
KEYPORT, WA
PRE-ROO DATA COLLECTICS1!
CTO'89VO*"flDUNDi\ai3TINTt.DRW V)M!
-------
Annual Report, 2010
Operable Unit 1
Contract N44255-09-D-4005
LTM/O / Task Order 18
Final
June 15, 2011
0.5 U
cis-1,2-DCE
cis-1.2-DCE
mm
0.70 JD
fHH
MWV09
TCE
LOT No 78
«s-1.2-DCE
/
TORPEDO ROAD
s
Monitoring Well in Upper
Aquifer
fj/L = micrograms per liter
TCE = 1,1,1-trichioroethene, (j/L
cis = 1,2-dichloroethene, |j/L
VC = vinyl chloride, p/L
J = estimated result
U = not detected at value shown
D = the reported result is from a
dilution
H
! CJJ'J
0 1Q0 200
Scale in Feet
Plantation
Figure 6-5
Task Order 18
U.S.NAVY
SEALASKA
Distribution of Seiected Target VOCs
For Intermediate Aquifer
NBK Keyport
Area 1
June 2010
Annual Report 2010
SES-LTM/O-l 1-0346
6-17
-------
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(Ecok^caf)
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O.S3
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(Huron Health)
0.000043
O.OCB027
CLEAN
CCMPflEWtCiVE
LONG-^RM
emwmmpt.
ACTION NAVY
Figure 30
OlsirlbutlKi of Aroclors in Lfpp« Aquifer
and SurfaCB Wster
CT0189
hftJWC KEYPORTCfU 1
wpom.m
PREflOD DATA COLLECTION
cTovsfWftRONKTOrypm .Kf mi
-------
Annua] Repon. 20 J1
Operable Unit I
Contract N44255-09-D-4005
LTM/O/Task Order 30
Final
Jnlv 27. 2012
%
CULVERT STBEGATE
LOT No 7B
1B89
SEDIMENT
REWQVAL
AREA
XX
North '
Plantation 1
ORPEDO ROAD
BONDARV
L0t 4A
FORMER
WILL g
PaUw ui m
GAOBERRY STREET
0 100 200
e in Feet
U.S.NAVY
SEALASKA
Figure 1-2
Location of OU 1, Area 1
Task Order 30
NBK Keyport
OU 1 Annual Report 2011
S>:s-I.TM,0-I2-O4oj
-4
-------
ATTACHMENT B
Concentration Trend Charts Prepared by the Optimization Review Team
35
-------
1MW-1 Vinyl Chloride Concentration Trend
1600
1400
1200
1000
^ 800
600
400
200
0
~ ~
~ »
~~ ~~ ~
~ 4 4
~ ~ ~ ~
Vr
vl^'7-00^!^^006 Il6'*009
MW1-2 cis-l,2-DCE and Vinyl Chloride
Concentration Trends
2000
1800
1600
1400
1200
*53 1000
800
600
400
200
0
% ~
~ Vinyl Chloride
¦ cis-l,2-DCE
" " 1%
COCO 4*
|aM'i998A|-i.el'2-o0'S"-y|^l^o0tol^0'a006 116|7-°°9
36
-------
MW1-4 TCE cis-l,2-DCE and Vinyl Chloride
Concentration Trends
100000
u 10000
a
•H
.!£ 1000
¦D
c
ra
UJ
u
ao
a.
100
10
TCE
cis-1,2 DCE
A Vinyl Chloride
1000
10000
100 -5.
a;
"E
_o
-C
u
>¦
c
5
10
no
3.
MW1-16 1,1-DCA, cis-l,2-DCE and Vinyl
Chloride Concentration Trends
100000
u 10000
Q
.•i iooo
ra
<
u
Q
100
10
ao
=L
~ 1,1-DCA
¦ Cis-1,2-DCE
A Vinyl Chloride
Ur..
.1^2% ~~
*
- .Ot
n
r 100000
- 10000
- 1000
- 100
- 10
1
0.1
a;
"E
_o
-C
u
>¦
c
5
M
3.
37
-------
MA-12 cis-l,2-DCE and Vinyl Chloride
Concentration Trends
u
o
ra
<
U
O
ao
a.
1000
100
10
A A. .. . *
¦ Vinyl Chloride
ACis-l,2-DCE
38
------- |