PB94-964628
EPA/ROD/R10-94/079
November 1994
EPA Superfund
Record of Decision:
East Harbor Operable Unit,
Wyckoff/Eagle Harbor, WA,
9/29/94
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U.S. Environmental Protection Agency
Region 10
Seattle, Washington
East Harbor Operable Unit
Wyckoff/Eagle Harbor Superfund Site
RECORD OF DECISION
September 1994
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CONTENTS
Page
LIST OF FIGURES iv
LIST OF TABLES v
LIST OF ACRONYMS vi
DECLARATION 1
DECISION SUMMARY
1. OVERVIEW 4
2. SITE LOCATION AND DESCRIPTION 5
2.1 Site Location 5
2.2 Current Land Use 5
2.3 Environmental Setting 8
3. SITE HISTORY AND ENFORCEMENT ACTIONS 11
3.1 Site Background 11
3.2 Site Listing 11
3.3 CERCLA Enforcement Actions 12
3.4 Eagle Harbor RI/FS 12
3.5 East Harbor Removal Action < 12
4. COMMUNITY RELATIONS ACTTvTnES 14
5. SCOPE AND ROLE OF OPERABLE UNITS
WITHIN THE SITE STRATEGY 15
6. SITE CHARACTERISTICS 16
6.1 Scope of RI/FS 16
6.2 RI Sampling 16
6.3 Nature and Extent of Sediment Contamination 17
6.4 Sources of Contamination 22
6.5 Other Contaminated Media 22
6.6 Depth of Concern 25
6.7 Routes of Migration 25
6.8 Potentially Exposed Populations 27
6.9 Principal Threat 27
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7. SUMMARY OF SITE RISKS 28
7.1 Human Health Risk Assessment 28
7.1.1 Identification of Chemicals of Concern 28
7.1.2 Toxicity Assessment . 28
7.1.3 Exposure Assessment 31
7.1.4 Risk Characterization 34
7.2 Ecological Assessment 35
7.2.1 Chemicals of Concern 36
7.2.2 Biological Effects 36
7.3 Summary of Risk Assessment 38
7.4 Special Site Characteristics 38
8. DESCRIPTION OF ALTERNATIVES 39
8.1 Applicable or Relevant and Appropriate Requirements (ARARs) 39
8.2 Estimated Cleanup Areas ' 41
8.3 Common Components of Alternatives 45
8.3.1 Institutional Controls 47
8.3.2 Source Control 47
8.3.3 Natural Recovery 47
8.3.4 Sampling During Remedial Design 49
8.3.5 Monitoring 49
8.4 Description of the Alternatives 50
9. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES 55
9.1 Threshold Criteria 55
9.1.1 Overall Protection of Human Health and the Environment 55
9.1.2 Compliance with ARARs 56
9.2 Primary Balancing Criteria 56
9.2.1 Long-Term Effectiveness and Permanence 56
9.2.2 Reduction of Toxicity, Mobility, or Volume Through Treatment 57
9.2.3 Short-Term Effectiveness 57
9.2.4 Jaiplementability 58
9.2.5 Cost-Effectiveness 59
9.3 Modifying Criteria 59
9.3.1 State and Tribal Acceptance 59
9.3.2 Community Acceptance 59
10. SELECTED REMEDY 61
10.1 Cleanup Objectives . 61
10.1.1 Sediment Standards 62
10.1.2 East Harbor Cleanup Goals and Objectives 66
10.1.3 Rationale for Selected Cleanup Objective for East Harbor 68
10.1.4 Comparison with West Harbor 69
10.2 Problem Areas and Actions 70
10.2.1 Subtidal Areas 70
10.2.2 Intertidal Areas 72
10.2.3 Institutional Controls/Site Use Restrictions 74
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10.3 Implementation 75
10.3.1 Coordination with Contaminant Source Control 76
10.3.2 Monitoring Prior to Source Control 77
10.3.3 Potential Necessary Actions Prior to Final Remedial Action 77
10.3.4 Final Sediment Remedial Design and Remedial Action 78
10.3.5 Post-Remedial Action Monitoring and Maintenance 79
10.4 Estimated Costs 81
10.5 CERCLA Five-Year Review 82
11. STATUTORY DETERMINATIONS 83
11.1 Protection of Human Health and the Environment 83
11.2 Compliance with ARARs 83
11.3 Cost Effectiveness 86
11.4 Utilization of Permanent Solutions and Alternative Technologies 86
11.5 Preference for Treatment as a Principal Element 87
12. DOCUMENTATION OF SIGNIFICANT CHANGES 88
REFERENCES 89
APPENDIXES
Appendix A: Proposed Plan
Appendix B: Responsiveness Summary - 1994 Proposed Plan Comments
Attachment A: Responsiveness Summary - 1991 Proposed Plan Comments
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List of Figures
FIGURE NUMBER PAGE
Figure 1. Regional Setting 6
Figure 2. Area Map 7
Figure 3. Wyckoff/Eagle Harbor Superfund Site Operable Units 9
Figure 4. Land Use Map 10
Figure 5. Eagle Harbor Sample Locations 19
Figure 6. Subtidal Background Locations 20
Figure 7. Metals in Intertidal Sediment Relative to Background 21
Figure 8. Subtidal Mercury Concentrations 23
Figure 9. Concentrations of TPAH at Stations Samples During RI and PI 24
Figure 10. Areas of Ferry Propeller Influence 26
Figure 11. East Harbor Areas Defined by Sediment Management Standards 44
Figure 12. Comparison of Eagle Harbor Subtidal Bioassay Results to Sediment Standards 46
Figure 13. East Harbor ROD Areas 63
Figure 13A. Other Specific Areas Identified in Selected Remedy 64
Figure 14. Framework for the Timing of Remedial Activities 65
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List of Tables
Table 1 List of Technical Memoranda for Eagle Harbor 13
Table 2 1988 AETs for Puget Sound 18
Table 3 Potential Exposure Pathways Retained for Risk Assessment 29
Table 4 Chemicals of Potential Concern for Human Health 30
Table 5 Human Toxicity Factors of Chemicals Retained for Risk Quantification 32
Table 6 Exposure Assumptions for Human Health Risk Assessment 33
Table 7 Screening of Alternatives 40
Table 8 Sediment Standards Chemical Criteria 42
Table 9 Sediment Standards Biological Criteria 43
Table 10 Area Estimates for the East Harbor 45
Table 11 Summary of Common Components for East Harbor Remedial Alternatives 48
/
<.
Table 12A Intertidal Sediments - Estimated Costs of East Harbor Sediment Cleanup Alternatives S3
Table 12B Subtidal Sediments - Estimated Costs of East Harbor Sediment Cleanup Alternatives 53
Table 13 Estimated Time to Implement East Harbor Remedial Alternatives 55
Table 14 Estimated Costs of East Harbor Selected Remedy 80
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List of Acronyms
AET
AKARTs
ARAR
BMP
CAD
CERCLA
COE
Ecology
EPA
HPAH
LPAH
MCUL
MLLW
NCAC
NCP
NOAA
NPDES
NPL
O&M
PAH
PI
POTW
PRP
PSAMP
PSDDA
PSEP
PSWQA
RCRA
RfD
RI/FS
ROD
RME
SF
SQS
TBC
TPAH
UST
Apparent Effects Threshold
All Known Available and Reasonable Methods of Treatment
Applicable or Relevant and Appropriate Requirement
Best Management Practice
Confined Aquatic Disposal
Comprehensive Environmental Response, Compensation, and Liability Act
U.S. Army Corps of Engineers
Washington Department of Ecology
U.S. Environmental Protection Agency
High Molecular Weight Polynuclear Aromatic Hydrocarbons
Low Molecular Weight Polynuclear Aromatic Hydrocarbons
Minimum Cleanup Level
Mean Lower Low Water
Nitrogen Containing Aromatic Compounds
National Contingency Plan
National Oceanic and Atmospheric Administration
National Pollutant Discharge Elimination System
National Priorities List
Operations and Maintenance
Polynuclear Aromatic Hydrocarbon
Preliminary Investigation
Publicly Owned Treatment Works
Potentially Responsible Party
Puget Sound Ambient Monitoring Program
Puget Sound Dredged Disposal Analysis
Puget Sound Estuary Program
Puget Sound Water Quality Authority
Resource Conservation and Recovery Act
Reference Dose
Remedial Investigation/Feasibility Study
Record of Decision
Reasonable Maximum Exposure
Slope factor
Sediment Quality Standards
Other Factors To Be Considered
Total Polynuclear Aromatic Hydrocarbons
Underground Storage Tank
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DECLARATION
FOR THE
RECORD OF DECISION
SITE NAME AND LOCATION
Wyckoff/Eagle Harbor Superfund Site
East Harbor Operable Unit
Bainbridge Island, Washington
STATEMENT OF BASIS AND PURPOSE
This decision document presents the final remedial action selected by the U.S. Environmental
Protection Agency (EPA) for the East Harbor operable unit (East Harbor) of the Wyckoff/Eagle
Harbor Superfund site, Bainbridge Island, Kitsap County, Washington.
The remedy was chosen in accordance with the Comprehensive Environmental Response,
Compensation, and Liability Act of 1980 (CERCLA), as amended, and, to the extent practicable, the
National Oil and Hazardous Substances Pollution Contingency Plan. This decision is based on the
Administrative Record for this site.
As described in Section 9.3 of this document, concurrence on the selected remedy by the State of
Washington Department of Ecology is under consideration.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from this site, if not addressed by implementing
the response action selected in this Record of Decision, may present an imminent and substantial
endangerment to public health, welfare, or the environment.
DESCRIPTION OF THE REMEDY
The selected remedy described in this Record of Decision addresses contaminated sediments in the
East Harbor, one of four operable units at the Wyckoff/Eagle Harbor site. This is the second Record
of Decision to be completed for the site.
Sediments in the East Harbor are contaminated with polynuclear aromatic hydrocarbons and other
hazardous substances. The principal threat is defined as sediments containing free-phase oily
contamination. The selected remedy addresses the principal threat and other sediments contaminated
at levels which cause significant adverse effects on marine organisms, by combining sediment capping
in subtidal areas with monitoring in intertidal areas to confirm the predicted recovery of intertidal
sediments through natural processes.
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Over fifty acres of heavily contaminated subtidal sediments in the East Harbor were recently capped
under CERCLA removal authorities to address documented adverse biological effects and free-phase
oily contamination. The selected remedy incorporates the existing cap and addresses remaining areas
of contamination in the East Harbor with a phased cleanup approach.
The first phase will be completed concurrent with ongoing EPA efforts to control sources of
contamination from the adjacent Wyckoff Facility operable unit, an inactive wood-treating facility.
Initial East Harbor actions include:
enhancement of existing institutional controls to reduce public exposure to contaminated fish
and shellfish and to protect the existing cap;
monitoring and maintenance of the existing cap;
environmental monitoring to assess the effectiveness of source control efforts; and
other actions necessary to ensure protection of human health and the environment, such as
demolition of in-water structures, identification of potential nearshore sediment hotspots, and
evaluation of contaminant breakdown rates.
Final sediment cleanup actions are to be completed after a determination that sources of contamination
at the adjacent Wyckoff Facility operable unit have been sufficiently controlled. Final sediment
cleanup actions include:
additional capping in remaining subtidal areas of concern for adverse biological effects;
c
monitoring the success of natural recovery in intertidal areas predicted to achieve the long-
term sediment cleanup objective without sediment remedial action; and
monitoring contaminated areas where active remediation cannot be implemented due to
engineering feasibility or sensitive ecological conditions.
EPA will be the lead agency for implementing sediment remediation in the .East Harbor and will
coordinate activities in the East Harbor with ongoing cleanup work at other operable units.
STATUTORY DETERMINATIONS
The selected remedy is protective of the marine environment and human health, complies with federal
and state requirements that are legally applicable or relevant and appropriate to the remedial action,
and is cost-effective. This remedy uses permanent solutions and alternative treatment technologies to
the maximum extent practicable for this operable unit. However, because treatment of the principal
threat of this operable unit was not found to be practicable, this remedy does not satisfy the statutory
preference for treatment as a principal element.
Areas of sediment containing free-phase oily contamination constitute the principal threat at this
operable unit. For low volumes of subtidal sediment containing free-phase oily contamination,
treatment could be an appropriate remedy but would require dredging. Dredging was judged to pose
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a significant short term risk to the environment due to potential releases of oily contamination and
contaminated fine particles. Treatment or disposal of dredged sediments at an upland facility would
involve complex implementability issues, high costs, and extended tune frames for effective treatment.
Subtidal areas containing free-phase contamination were successfully capped under CERCLA removal
authorities. Other areas of sediment contamination in-the East Harbor, while potentially toxic to
marine organisms, contain relatively low levels of contamination. Containment is an appropriate
remedy for such areas, which represent high volumes at low levels of contamination.
Because this remedy will result in hazardous substances remaining on site above health-based and
environmentally-based cleanup levels, a review will be conducted within five years after
commencement of remedial action to ensure that the remedy continues to provide adequate protection
of human health and the environment.
Date Chuck Clarke
Regional Administrator
U.S. Environmental Protection Agency
Region 10
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1. OVERVIEW
This Decision Summary provides a description of the site-specific factors and analyses that led to
selection of the remedy for the East Harbor operable unit (East Harbor) of the Wyckoff/Eagle Harbor
Superfund site. It includes information about the site background, the nature and extent of
contamination, the assessment of human health and environmental risks, and the identification and
evaluation of remedial alternatives.
The Decision Summary also describes the involvement of the public throughout the process, along
with the environmental programs and regulations that may relate to or affect the alternatives. The
Decision Summary concludes with a description of the remedy selected in this Record of Decision
(ROD) and a discussion of how the selected remedy meets the requirements of the Comprehensive
Environmental Response, Compensation, and Liability Act (CERCLA) and the National Contingency
Plan (NCP).
The Decision Summary is presented in the following sections:
Section 2 Describes general characteristics of the site and individual operable units,
Section 3 Provides site history and previous investigations or enforcement activities,
Section 4 Presents highlights of community participation,
Section 5 Describes the scope of the response action in the context of the overall site strategy,
Section 6 Presents site characteristics,
Section 7 Provides a summary of site risks,
Section 8 Describes the cleanup alternatives evaluated,
Section 9 Compares the analyses in terms of the EPA evaluation criteria,
Section 10 Presents the selected remedy,
Section 11 Documents the conformance of the selected remedy with statutory requirements, and
Section 12 Describes significant changes between the preferred alternative presented in the
1994 Proposed Plan and the remedy selected in the ROD.
Documents supporting this Decision Summary are included in the Administrative Record for the East
Harbor. Key documents include the following: the Remedial Investigation (RI) Report (November
1989), subsequent technical memoranda, the Revised Risk Assessment (May 1991), and the
Feasibility Study (FS) (November 1991), which provide the results of the overall Eagle Harbor
RI/FS; the initial Eagle Harbor Proposed Plan (December 16, 1991), which addressed both East and
West Harbor sediments and proposed an interim cleanup plan for heavily contaminated areas of the
East Harbor; the Action Memorandum (June IS, 1993), which authorized implementation of this plan
through placement of a sediment cap in the East Harbor; the On-Scene Coordinator's report (COE,
July 1994 Draft), which describes the completed cap; and the subsequent East Harbor Proposed Plan
(June 8, 1994), which proposed a final cleanup plan for remaining areas of contamination in the East
Harbor.
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2. SITE LOCATION AND DESCRIPTION
2.1 Site Location
The Wyckoff/Eagle Harbor Superfund site is located on the east side of Bainbridge Island, in Central
Puget Sound, Washington (Figure 1). The site includes an inactive 40-acre wood-treating facility,
contaminated sediments in adjacent Eagle Harbor, and other upland sources of contamination to the
harbor, including a former shipyard (Figure 2). The site is currently divided into four administrative
areas, known as "operable units" (Figure 3).
Sediments in areas of Eagle Harbor are contaminated with polynuclear aromatic hydrocarbons (PAHs)
and other organic compounds, as well as with metals, primarily mercury. EPA's Remedial
Investigation (RI) of sediment contamination in Eagle Harbor (CH2M Hill, November 1989) initially
addressed the harbor as a single unit concurrent with enforcement activities at the Wyckoff Facility.
After completion of the Eagle Harbor Feasibility Study (FS) (CH2M Hill, November 1991), EPA
proposed die administrative separation of the Harbor into East Harbor and West Harbor operable
units (Eagle Harbor Proposed Plan, 1991).
Groundwater and soils at the wood-treating facility (the Wyckoff Facility operable unit) are
contaminated with chemicals from the wood treatment process, primarily creosote-derived PAHs and
pentachlorophenol. A groundwater and oil extraction system and treatment plant have been in
operation at the facility since 1990 as part of an Expedited Response Action (ERA) aimed at
controlling releases of contamination to the harbor. Although wood-treating operations at the
Wyckoff Facility ceased in 1988, contamination from the Wyckoff Facility continues to affect areas of
die East Harbor through groundwater movement and oily seeps. In 1993, under CERCLA removal >
authorities, EPA implemented the initial sediment cleanup proposed for the East Harbor, placing a
sediment cap in a heavily contaminated subtidal area. The cap, relatively distant from ongoing
intertidal seeps, addressed areas where sediment contamination was shown to cause significant adverse
biological effects in biological tests, including areas of free-phase oily contamination.
EPA recently divided the Wyckoff Facility into separate operable units for soil and groundwater and
has proposed an interim decision to support source control efforts (Wyckoff Facility Proposed Plan,
July 1994). These efforts are expected to control seepage of oily contamination and groundwater to
the East Harbor. Final remedies for soils and groundwater will be selected following completion of
the ongoing Wyckoff Facility RI/FS.
This ROD specifically addresses East Harbor sediments, including the existing cap and remaining
contaminated sediments.
2.2 Current Land Use
More than 15,000 people live on Bainbridge Island. Land use on Bainbridge Island, recently
incorporated as the City of Bainbridge Island, is principally residential, with some commercial and
industrial use (Figure 4). An urban area, formerly the City of Winslow (population 2,800), lies on
the north shore of the Harbor. Residences, commercial centers, a city park, several marinas, a yacht
repair yard, a bulkhead enterprise, and a ferry terminal characterize the northern shoreline. The
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NPE69J08 01 04 ' PIR1 / 0 3 5< / CJS / LKW
Figure 1
REGIONAL SETTING
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NPE69206.OJ.04/Area Mjp/4-J-94/lKW
;;--
0 1000 2000
Scale in Meters
I Wyckoff Facility 8 Queen City Yacht Club
2 Bainbridge Island Boatyard (proposed) 9 City of Winslow Public Pier
3 Tyee Yacht Club 10 Bainbridge Marine Services
4 Eagledale Moorings 11 Eagle Harbor Boat Repair
5 Eagle Harbor Marina (Leased from Bainbridge Marine Services)
6 Harbor Marina l2 DOT Ferry Maintenance Facility
7 Winslow Wharf Marina l3 DOT Ferry Terminal
Figure 2
AREA MAP
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western and southern shores are primarily lined with residences, farms, marinas, and a boatyard. On
the south shore at the harbor mouth, the former wood-treating facility extends into the harbor on fill.
A significant use of the harbor is ferry transport of vehicles and passengers between the City of
Bainbridge Island and Seattle. Currently, approximately twenty runs are made per day. The harbor
is also used for moorage of pleasure boats, house boats, and working boats. Fishing, crabbing, and
clam-digging were common recreational activities until 1985, when the Bremerton-Kitsap County
Health District issued a health advisory to address bacterial and chemical contamination of seafood in
Eagle Harbor. The advisory, recommending against the harvest and consumption of fish and
shellfish, has significantly reduced recreational harvest of seafood from the harbor.
Eagle Harbor is within the usual and accustomed fishing area of the Suquamish Tribe, whose
reservation is located on the Kitsap Peninsula.north of Bainbridge Island. The Suquamish Tribe
retains the right to harvest fish and marine invertebrates and to have fishery resource habitat areas
protected within the Suquamish Tribe's usual and accustomed fishing area.
2.3 Environmental Setting
Eagle Harbor is a Puget Sound embayment approximately 202 hectares (500 acres) in area, with a
watershed (Figure 4) of approximately 1,327 hectares (3,280 acres). The upper harbor is shallow,
but the central channel is between 6 and 15 meters (20 to 50 feet) in depth. Several small creeks feed
the harbor, and at the harbor mouth a long sandbar named Wing Point extends southward from the
north shore.
The harbor supports several fish resources. Coho and chum salmon once used the creek on the north'
shore to spawn, and fingerlings have been released there periodically. The creek at the head of the
harbor is a salmon nursery, and it is possible that the drainage on the south side is used as a chum
spawning ground and nursery. Eagle Harbor may also be a spawning ground for surf smelt and
Pacific sand lance (Washington Department of Fisheries, 1992). Other fish and invertebrates present
in the harbor include several flatfish species, rockfish, pile perch, cod, lingcod, crabs, and shrimp.
Several shellfish species are present in intertidal and subtidal areas.
Bainbridge Island supports a wide variety of resident and migratory birds and other wildlife. Major
bird groups represented include waterfowl, shorebirds, gulls, songbirds, and raptors. Although
residents report sightings of bald eagles, the closest bald eagle nesting location is approximately three
miles from the site. Although habitat for marbled murrelet may exist on Bainbridge Island, there
have been no reported sightings. No critical habitats are formally designated near the site.
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NPE69208.02.04 POFM 8/3/94 CJS LKW
VO
I
CITY OF
BAINBRIDGE ISLAND
M Approximate Location .
^^ " " of Property Line
Note: OU Boundaries are approximate
0 150 300 600
_-
Scale in Meters
Figure 3
WYCKOFF/EAGLE HARBOR
SUPERFUND SITE OPERABLE UNITS
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NPE69206.02.04A.and Use Map/8-4-94/LKW
APPROXIMATE
WATERSHED
BOUNDARY
YEOMALT POINT
WIN« POINT
BilnbtWg* Itland Zoning
Ru-U Rural 10w«Hng IMW.S Ao«
Ru-1 Riinl 1 OwtOIng UnVAer*
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Figure 4
LAND USE MAP
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3. SITE HISTORY AND ENFORCEMENT ACTIVITIES
3.1 Site Background
Prior to non-Indian development of Bainbridge Island in the mid-nineteenth century, a Suquamish
Indian village and burial site were located on the north shore of Eagle Harbor, and the harbor was an
important shellfish harvest area for the Suquamish Tribe. Subsequent land use was residential,
timber-related, or agricultural. Starting in 1903, a major shipyard was established on the north shore
of Eagle Harbor, and wood-treating operations began on the south shore in 1905.
The early days of the shipyard emphasized wooden ship-building. After flourishing during World
War I, the yard slumped during the 1930's. In the 1940's and 50's, the emphasis was on construction
and repair of military ships, conversion of ships to wartime use, and postwar decommissioning under
contracts with the Navy, Army, Coast Guard and other military entities. Repair contracts dwindled
into the late 1950's, and in 1961 the property was sold and subsequently divided.
Wood treating operations at the Wyckoff Facility began in 1905 and continued until 1988 through
several changes of ownership. Pressure treatment with creosote was the primary method of wood
preservation, although pentachlorophenol also came into use. Preservative chemicals were delivered to
the facility by barge and ship and stored in tanks on the property. Spills, leaks, and drippage entered
the ground directly or through unlined sumps. Wastewater was discharged into Eagle Harbor for
many years, and the practice of storing treated pilings and timber in the water continued until the late
1940's.
During the 1970's, efforts were made to address oil seepage on beaches adjacent to the^ Wyckoff
Facility through inspections and recommendations. In March 1984, the National Oceanic and
Atmospheric Administration (NOAA) advised EPA and the Washington Department of Ecology
(Ecology) that samples of sediments, fish, and shellfish from Eagle Harbor contained elevated levels
of PAHs in both sediments and biota (Malins, 1984a, 1984b).
In August of 1984, EPA issued a Unilateral Administrative Order (UAO) requiring the Wyckoff
Company to conduct environmental investigation activities under the Resource Conservation and
Recovery Act (RCRA) Section 3013 (42 U.S.C. § 6924), and Ecology issued an Order requiring
immediate action to control stormwater runoff and seepage of contaminants. Data collected at the
time revealed the presence of significant soil and groundwater contamination.
3.2 Site Listing
The Wyckoff/Eagle Harbor site was proposed to the NPL in September 1985. Under the Washington
State Hazardous Waste Cleanup Program, Ecology completed a Preliminary Investigation of sediment
contamination in Eagle Harbor (November 1986). In 1985, NOAA completed a study relating the
presence of PAHs in sediment to the high rate of liver lesions in English Sole from Eagle Harbor
(Malins, 1985). In March 1987, the Wyckoff Company entered into an Administrative Order on
Consent with EPA for further investigation of the facility.
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The site was added to the NPL in July 1987, with EPA as lead agency. EPA initially separated the
site into two operable units, initiating the RI/FS for Eagle Harbor and using enforcement authorities
to address ongoing releases of contamination from the wood-treating facility.
3.3 CERCLA Enforcement Actions
EPA enforcement actions at the wood-treating facility after the site listing on the NPL include the
following:
A July 1988 Administrative Order on Consent, under which the Wyckoff Company agreed to
conduct an Expedited Response Action (ERA). The ERA, intended to minimize releases of
oil and contaminated groundwater to the East Harbor, called for a groundwater extraction and
treatment system and other source control measures.
A June 1991 Unilateral Administrative Order requiring the Wyckoff Company (now Pacific
Sound Resources) to continue the ERA with some enhancements. The UAO calls for
increased groundwater extraction and treatment rates, improved system monitoring, and
removal of sludge stored or buried at the Wyckoff Facility.
A November 1993 Administrative Order on Consent, under which potentially responsible
parties are completing remedial design pursuant to the West Harbor ROD.
A Consent Decree resolving Pacific Sound Resources' liability at this and another Superfund
site. This agreement was lodged and entered in court in 1994.
A potentially responsible party (PRP) search was initiated in 1987 to identify parties potentially liable
for response costs for Eagle Harbor, and ten parties were initially notified of potential liability in
1987 and early 1988. Continued PRP search efforts resulted in the notification of an additional party
in January 1992. In addition to the Consent Decree with Pacific Sound Resources, another PRP
resolved its liability in a bankruptcy settlement with EPA. Four parties have been notified that EPA
does not currently consider them PRPs.
3.4 Eagle Harbor Remedial Investigation (RI) and Feasibility Study (FS)
CH2M Hill conducted the Eagle Harbor RI under EPA's REM IV contract. RI fieldwork began in
early 1988, and the RI Report was issued November 1989. Subsequent field activities were
conducted in 1989 and 1990 by CH2M Hill under the ARCS contract. These activities were
described in technical memoranda and summarized in the FS, issued November 1991. Key technical
memoranda are. listed on Table 1.
3.5 East Harbor Removal Action
As noted previously, after completion of the RI/FS, EPA proposed initial cleanup actions in the East
Harbor operable unit (Eagle Harbor Proposed Plan, 1991). The proposed cleanup was a clean
sediment cap over heavily contaminated sediments in the East Harbor, including at a minimum a
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sediment hotspot in the central channel, and extending if possible to other areas where acute toxicity
of the sediments to marine organisms had been documented during the RI/FS. EPA documented its
decision to complete the cap under CERCLA removal authorities in an Action Memorandum (June
15, 1993). The cap was completed by the U.S. Army Corps of Engineers and their contractors over
a six-month period starting September 1993. Cap materials were obtained from the Snohomish River
as part of a federal navigation project and placed in over 54 acres of subtidal sediments in the East
Harbor. Completion of the cap cost approximately $1.5 million, a significant savings relative to costs
estimated in the FS for a comparable area. Cap placement and monitoring results are described in the
draft On-Scene Coordinator's Report (COE July 1994).
Table 1 . List of Technical Memoranda for Eagle Harbor
Memorandum Title
Technical Memorandum on Baseline ARARs Analysis (#1)
Technical Memorandum on Alternatives Identification and
Screening (#2)
Technical Memorandum on Development of Remedial
Action Objectives (#3)
Technical Memorandum on the Geophysical Survey (#6)
Technical Memorandum on the Sedimentation Rate
Evaluation (#4)
.Technical Memorandum on Fish Tissue Sampling (#8)
Technical Memorandum on the Need for Treatability
Studies (#9)
Technical Memorandum on the Subsurface Hydrology
Study (#7)
Technical Memorandum on Source Identification (#5)
Technical Memorandum on Northshore Sampling (#10)
Technical Memorandum on Deep Sediment Sampling (#1 1 )
Technical Memorandum on Marine Biota Tissue Sampling
and Analysis (#13)
OU"
EH/WH
EH/WH
EH/WH
EH
EH/WH
EH/WH
EH/WH
EH
EH/WH
WH
EH
EH/WH
Date Finalized
September 1989
September 1 989
December 1989
December 1989
December 1989
March 1990
4.
May 1 990
March 1990
October 1990
July 1 990
July 1990
April 1991
* These documents are included as part of the Administrative Record for the East Harbor.
6 The focus of each document is noted as EH (East Harbor) or WH (West Harbor) Operable Unit (OU).
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4. COMMUNITY RELATIONS ACTIVITIES
Sections 113(k)(2)(B) and 117 of CERCLA set forth the minimum requirements for public
participation at sites listed on the NPL. The EPA has met these requirements and maintained an
active community relations program at the site.
A community relations plan for the Wyckoff/Eagle Harbor site was prepared by Ecology in 1985 and
adopted by EPA after the site was listed on the NPL in 1987. Notice of the listing of the site was
published in the local paper, and the mailing list was compiled from a clip-out portion of the notice.
Currently, the mailing list comprises over 650 addresses. Fact sheets have been mailed to interested
citizens three or four times a year since the site listing.
Section 4 of the West Harbor ROD describes community relations activities during the RI/FS for
Eagle Harbor. These activities culminated in the issuance of a Proposed Plan (December 1991) for
final cleanup in the West Harbor and capping of a portion of the East Harbor under an interim
decision. Two community meetings were held to answer questions and accept public comments.
Community comments were divided between support for EPA's preferred alternative and preference
for lower cost alternatives or combinations of alternatives.
Since then, EPA has completed the first phase of cleanup in the East Harbor, as proposed. The work
was conducted under CERCLA removal authorities over a six-month period ending in March 1994.
EPA made the determination that the community relations requirements for non-time critical removal
actions were satisfied by the RI/FS processes. EPA's response to comments on the 1991 Proposed
Plan is attached to the June 15, 1994 Action Memorandum documenting EPA's decision to complete
the removal action. Between July 1993 and March 1994 additional outreach was completed. EPA
published a newspaper announcement, sent out a public notice and several fact sheets, iuid held a
community meeting to respond to questions and concerns. An Administrative Record is on file at the
public library on Bainbridge Island.
After completing the removal action, EPA issued a Proposed Plan for final cleanup of remaining
contaminated areas of the East Harbor on June 8, 1994. A thirty-day public comment period ran
from June 8 through July 8, 1994. A community meeting was announced in the local papers and held
on June 22, to answer questions and accept public comment. Five people attended this meeting. In
addition to verbal comments provided at the meeting, EPA received five letters commenting on the
Proposed Plan. Comments generally supported EPA's preferred alternative, suggesting that
clarification or additional detail be provided in the ROD. The Responsiveness Summary (Appendix B
of this ROD) outlines and responds to public comments provided during the comment period.
The remedy in this ROD was selected in accordance with CERCLA, as amended, and with the NCP.
The decision is based on information in the Administrative Record for the site.
- 14-
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5. SCOPE AND ROLE OF OPERABLE UNITS WITHIN THE SITE STRATEGY
Different environmental media, sources of contamination, public accessibility, enforcement strategies,
and environmental risks in different areas of the Wyckoff/Eagle Harbor site have led to the division
of the Wyckoff/Eagle Harbor site into operable units.
Coordination between the operable units is an important element of the overall site cleanup. The
current division of the site is as follows:
East Harbor subtidal and intertidal sediments (Operable Unit 1)
Wyckoff Facility soils (Operable Unit 2)
West Harbor subtidal and intertidal sediments and upland sources (Operable Unit 3)
Wyckoff Facility Groundwater (Operable Unit 4)
A ROD was completed for West Harbor sediments (Operable Unit 3) in 1992. This ROD presents
the final selected remedy for cleanup of the East Harbor only and is intended to address chemical
contamination of marine sediments, impacts to marine organisms, and related human exposure
pathways.
Other types of environmental or public health problems not caused by hazardous substances,
pollutants, or contaminants (as defined by CERCLA) within the site boundaries are beyond the scope
ofCERCLA authorities and are the responsibility of other federal, state, tribal, or loc^l programs.
Examples of problems beyond the scope of this ROD include problems related to bacterial
contamination and impacts to marine organisms from physical disturbances such as propeller wash or
shoreline uses. EPA coordinates with these other programs as appropriate.
- 15-
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6. SITE CHARACTERISTICS
This section summarizes information obtained during the RI/FS, including sources of contaminants,
affected media, and the characteristics of the contamination. It describes site conditions prior to
placement of the recently completed East Harbor sediment cap, described in Section 3.5.
6.1 Scope of Remedial Investigation/Feasibility Study
The RI/FS considered Eagle Harbor as a whole. The focus of the RI was to determine the nature and
extent of contamination in the harbor, identify significant sources of contamination, and assess threats
to human health and the environment due to chemical contamination.
Existing data which met EPA's quality assurance/quality control criteria were incorporated in the
RI/FS, including data collected by Ecology hi the 1986 Preliminary Investigation. As much as
possible, RI/FS field sampling, laboratory analytical and biological testing methods, and processes for
evaluating biological effects were consistent with methods and approaches developed for evaluating
conditions in Puget Sound and later incorporated in the State of Washington Sediment Management
Standards ("Sediment Standards"). The Sediment Standards were promulgated in April 1991 and are
the primary Applicable or Relevant and Appropriate Requirement (ARAR) for the site.
6.2 Remedial Investigation Sampling
Initial RI field work was conducted in 1988 and included:
intertidal and subtidal sediment sampling and chemical analyses to determine the nature and
extent of contamination;
shellfish tissue sampling and analyses to evaluate biological uptake and potential human health
risks;
laboratory bioassays to evaluate potential acute biological effects of the contamination on
marine organisms;
studies of the benthic (sediment-dwelling) community to evaluate potential chronic biological
effects; and
collection of oceanographic data for modeling contaminant fate and transport.
Ecology's 1986 Preliminary Investigation had identified a general problem area and problem
chemicals and had located a hotspot area of high PAH contamination. The problem areas and
chemicals were determined based on exceedance of Puget Sound Apparent Effects Thresholds (AET),
concentrations of contaminants which indicate possible biological effects.
Developed as part of the State of Washington's efforts to establish chemical standards for sediment
quality, AETs were used in the RI/FS. For a given chemical, an AET is the chemical concentration
-16-
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in sediment above which specific biological effects have always been observed in Puget Sound
studies. Chemical-specific AETs for Puget Sound have been developed for several different
biological tests. Table 2 lists chemical-specific AETs (for four biological tests) available in 1988.
Further discussion of AETs is provided in Section 7.
During the March 1988 field sampling for the RI, EPA collected subtidal sediment samples on an
extensive grid and analyzed them for PAHs and metals to fill data gaps from the Preliminary
Investigation (Figure 5). These were compared to specific AETs in order to identify areas of
potential biological effects. Areas where sediment concentrations of PAHs exceeded AETs for
benthic effects (i.e., effects on the abundance of sediment-dwelling organisms) were sampled in June
1988 for an expanded list of contaminants, including PAHs, nine Nitrogen-Containing Aromatic
Compounds (NCACs), four chlorophenols, other volatile and semivolatile compounds, and metals.
The June sampling also included collection of sediment samples for laboratory bioassays (using
amphipods and oyster larvae) and for evaluating the abundance and diversity of benthic organisms at
the sample locations. The same sampling was conducted at ten sample locations in uncontaminated
embayments near Eagle Harbor for comparison (Figure 6).
Intertidal sediment sampling was conducted in May and June, 1988, including a high, medium, and
low tide sample from each of 16 beach transects. Samples were analyzed for the same chemicals as
the June 1988 subtidal samples. At each transect, shellfish were collected and a composite sample of
tissue from each transect was analyzed. Intertidal locations near and outside the harbor mouth were
identified as background sampling transects (Figure 5, transects 1, 2, 3, 14, 15, and 16). Samples
from the intertidal background locations contained PAHs at levels comparable to the subtidal
background areas. Mercury was undetected at a detection limit of 0.1 mg/kg, comparable to subtidal
background.
Subsequent field activities, conducted in 1989 and 1990, included sampling of beach sediments on the
north shore of Eagle Harbor to further define an intertidal hotspot and to evaluate potential PAH
contamination along the north shore of Eagle Harbor. Tissues of fish from Eagle Harbor and Port
Madison (See Figure 6) were analyzed for metals. In the East Harbor, a diver survey, deep sediment
coring, subsurface hydrology studies, and a geophysical investigation were conducted to determine the
extent of a known subtidal sediment hotspot, investigate potential transport of contamination from the
Wyckoff Facility through the subsurface, and estimate the depth of contamination. Additional fish,
shellfish, and sediment sampling was conducted in 1990 to provide more complete information about
human health risks. The results of activities subsequent to the RI were presented in the technical
memoranda listed in Table 1 and incorporated in the FS (November 1991).
63 Nature and Extent of Sediment Contamination
This section summarizes the nature and extent of contamination in Eagle Harbor intertidal and
subtidal sediments, first for inorganic contaminants, then for organic contaminants.
For a number of metals, intertidal samples from Eagle Harbor were found to exceed the maximum
concentrations measured at background locations (Figure 7). The greatest number of metals detected
and the highest concentrations were detected in the West Harbor near the former shipyard. In
subtidal samples, copper and lead exceeded background by two to four times in much of the harbor,
and a few locations exceeded background values for zinc, cadmium, and arsenic. Subtidal mercury
-17-
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Table 2
1988 Puget Sound AFT for Selected Chemicals
Chemical
Apparent Effects Threshold
(Normalized to Dry Weight)
Ampbipocf
Oyster*
Bcnlhuf
Microtek
Metals (nut/kg dry weight: ppm)
Antimony
Arsenic
Chromhun
Copper
Lead
Mercury
Nickel
Silver
Zinc
2140V"
6.1"
960"
700
9.6
390
660
O.S9
>0.56*
1.600
ISO-
sr
5.1'
260"
530°
450"
2.1-
>140**
>6.1"
410"
700
9.6
390
530
0.41
>O.S6fc
1.600
Organic Compounds Qigflcg dry weight; ppfa)
Low molecular weight PAH
Naphthalene
Acenaphthylene
Acrnnphrhroe
Fluorene
2-Mahylmiphlhalrnr.
High molecular weight PAH
Pyrene
Phenols
Chrysenc
Benzofluoranthenes
Benzo(*)pyreoe
Iodeoo(l ,2.3-cd)pyrene
Dibenzo(a i*\*niii*»^^«|^
Benzo(g.h.i)perylene
Phenol
2-Mtihylphenol
4-Melhylpfaenol
2.4-Dimelhyl phenol
Penlachlorophenol
24.000-
2.400"
1.300-
2.000"
3.600-
6.900"
13.000"
1.900"
69,000"
30.000"
16.000"
5.100"
9,200"
7,800"
3.007
1.800"
540"
1.400"
1.200"
63
3.600-
7T
360-
5.200
2.100
>560>
500
540
1^00
960
670
17.000
2,500
3300
1.600
2.800
3.600
1.600
690
230
720
420
63
670
29
>140»
13,000"
2,700=
1300"
730-
1.000"
5.400"
4.400"
1.400"
69.000"
24.000"
16.000"
5.100"
9,200"
9.900"
3.600^
2,600"
970"
2.600"
1.200
IT
1.800"
210"
690-
5,200
2.100
>S60>
500
540
1.500
960
670
12.000
1,700
2.600
1.300
1.400
3.200
1.600
600
230
670
1.200
670
.29
>140*
Based on 287 station! (including recent lurveyi in Eagle Harbor, Elliott Bay, and Everett Harbor not included in the previous generation of 1986 AET).
'Based on 56 stations (an from Commencement Bay Remedial Investigation and Blair Waterway dredging study); unchanged since 19S6.
'Based on 201 stations (updated from earlier AET by incorporation of recent surveys in Eagle Harbor. Elliott Bay. and Everea Harbor not included in the
previous generation of 1986 AET).
'Based on 50 stations (all from Commencement Bay Remedial Investigation).
The value shown exceeds AET presented in Seller et al. (1986) because of addition of Puget Sound data from the Eagle Harbor. Elliott Bay. or Everett
Harbor surveys.
The vahte shown is less than AET1 presented in Beller et at. (1986) became of the exclusion of chemically or biologically anomalous stations from the
AET dataset.
The value shown exceeds AET established from Commencement Bay Remedial Investigation data (Barrick et al.. 1985) become of add ilion of Puget
Sound data presented in Beller et al. (1986)..
'Indicates that a defined AET could not be established because there were no "effects' stations with chemical concentrations above the highest
concentration among *no effects" stations.
Note: Asterisk () indicates AET data not available.
Source: PTI. 1988c.
-18-
-------
NPEaK08.02.OVEH SlirpU Uc«l«u/8O.S4//GFA/UCW
vO
I
M3:'''rJ>-, EH}7'J!:'-,, -'-',-" <,'
of*»4i#*&
|>-»H4«^gg|g
, OOD ' w A ~ ^
: - - 824 !, , -788* <
' ' ' " ole,' , ., ''EHi
^Vx^-\_^' 'i;^' /^ //
*"*~""^ ^v,'^'"---«1"A-'\^'^ ^l§:-^''l*68l^> -5^
Note: Samples taken during the Preliminary \,x' ' / '',-^s -**^*.*^~,
Investigation (June 1985) and the Remedial r'/'^^^ WYCKOF
Investigation (March 1988, June 1988) /"( FACILITY
r --^
.L.VJL.I1br
628 Sampling station (June 1985, March 1988,
June 1988)
9 Rl Intertidal sampling transect
Figure 5
EAGLE HARBOR
SAMPLE LOCATIONS
-------
101
S
g
Hi POnfMADlSON
Bainbndge
Island
107 SAMPLED IN MARCH 1988
11 d) SAMPLED IN MARCH AND
JUNE 1988
BREMERTON ;
Blake
Island
-20-
Figure 6
SUBT1DAL BACKGROUND
LOCATIONS
-------
NPE69208.02.04/Melals in lntertidaV8-5-94/LKW
WINSLOW
EH-7H
Sb2.3
As 4.4
Cu136
Pb129
Hg950
Zn 25.4
EH-SL
Pb 4.5
Znll.S
Maximum Background
Sediment Concentrations
mgAg
As Arsenic 7.1
Cu Copper 31.8
HQ Mercury 0.1
Pb Lead 8.9
Sb Antimony 7.0
Zn Zinc 51.6
EH-10. Station
Cu Metal ^
13.3 Factor over background maximum
(of 31.8 mg/kgforCu)
Scale in Meters
NOTE: Background stations Include transects 1.2, 3,14,15, and 16.
Figure 7
METALS IN INTERTIDAL
SEDIMENT RELATIVE TO
BACKGROUND
-------
concentrations exceeded maximum background values by between two and twenty times throughout
the harbor and were particularly high near the former shipyard (Figure 8).
PAHs, the predominant group of organic contaminants, were extremely high in intertidal sediments
adjacent to the Wyckoff Facility in the East Harbor. In the West Harbor, PAHs were elevated in
intertidal sediments near the ferry terminal and the former shipyard. Subtidal samples showed
widespread, heavy PAH contamination in the East Harbor and to a lesser extent in the West Harbor.
Estimated average concentrations of HP AH, the high molecular weight subgroup of PAH compounds,
were significantly higher than background values, and were highest in sediments north of the Wyckoff
Facility. Concentrations of total PAH (TPAH), low molecular weight PAH (LPAH), and NCACs
followed the same general pattern. Figure 9 shows ranges of TPAH concentrations measured in
subtidal sediments. Although chlorophenols were detected, it appears that contamination by
pentachlorophenol is not widespread.
On the basis of their widespread prevalence above AETs, mercury and the sixteen PAH were selected
as indicator contaminants to define areas for remediation. Contamination by other organic compounds
and metals in sediments is encompassed within areas of elevated PAH and mercury. The results of
the bioassays and benthic evaluations are discussed under Section 7.2 (Ecological Assessment), while
seafood contamination is discussed under Section 7.1 (Human Health Risk Assessment).
6.4 Sources of Contamination
A technical memorandum was developed (see Table 1) to identify sources of contamination to the
harbor. Based on historical information and chemical data from RI/FS sampling, the memorandum
listed probable major and minor sources of contamination to Eagle Harbor, including bom historical
and ongoing sources. The wood treating facility was identified as the major source of PAH,
particularly in the East Harbor, through both past operating practices and ongoing contaminant
transport through the subsurface.
In the West Harbor, PAH contamination in nearshore sediments appears to be from combustion
products, minor spills, and pilings and piers, while subtidal PAH contamination in the West Harbor is
believed to reflect a combination of these sources, disposal practices at the former shipyard, and
releases from the Wyckoff Facility. Elevated concentrations of metals, particularly near the former
shipyard, are clearly associated with past shipyard operations, including the application, use, and
removal (by sandblasting) of bottom paints and antifoulants.
6.5 Other Contaminated Media
The primary media of concern affected by contaminants in Eagle Harbor are intertidal and subtidal
sediments, as described in previous sections. Other media considered were marine surface water,
groundwater, and air.
Marine surface water and air were not identified as media of concern. Concentrations of
contaminants in the air were considered negligible at the harbor, because the contaminants are
primarily associated with sediments which remain under water all or much of the time. Contaminant
concentrations in the marine surface water were expected to be highly dilute relative to sediment
-22-
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NPO92Ct.02.04/SutXklal Mircury Concinl./«-]-94/SiiM.KW
I
NJ
£$& & <'&M$j$K%
. ,, »!<;;, -v ;, -JcH/fo-'-Emg'^656'-*- -'a- 'fiAeL^r'^'T*?^^,^*^
lEHo^^^r:; -bf, ".'- -.l^^^^^f^
; 'Sr"' ^St04 :'^/ ' 63< ^-;-^«^S';^in
^%^:;v s;^*:^
/@8^; $;" i'^:^f|ls5pi^^^
, ' ' ' ^^200 r!-7'ea |;t*;' "Y^,^
NOTE: Background concentrations were
less Than cTl mg/kg.
Figure 8
SUBTIDAL MERCURY
CONCENTRATIONS
-------
NPE69206.02.04/ConC. 01 TPAH/8-3-94/CJS/LKW
I
Is)
^Hy
0 150
300
600 Meters
> 1,000,000 u.g/kg
>100,C
> 10,000 ug/kg
V > 1,000 ug/kg
O > 100 ug/kg
15
Scale In Meters
j 1
Approximate depth In meters MLLW
_| I I
NOTE: For clarity, subtldal station numbers have been shortened
by eliminating the hyphen (e.g., EH08 rather than EH-08). The
three-digit subtidal station numbers are shown without the EH-
(e.g.. 714 instead of EH-714). EH stations (e.g., EH-08) were
sampled in the PI. Numerical stations (e.g., 714) were sampled
In the Rl.
SOURCE: EPA, November 1989.
Figure 9
CONCENTRATIONS OF TPAH
AT STATIONS SAMPLED DURING
Rl (June 1988) AND PI (1986)
-------
concentrations and would pose negligible human health risk from direct contact relative to exposure to
contaminated sediments. Ecology samples of surface water from ten Eagle Harbor locations
(Appendix B3 of the FS) did not exceed water quality criteria.
Wyckoff Facility groundwater, intertidal seeps, and soil contamination have been, and may continue
to be, sources of contamination for areas of the East Harbor. These sources are being addressed as
part of the ERA, other early actions, and ongoing remedial studies at the Wyckoff Facility.
Groundwater will not be directly addressed by cleanup actions in the East Harbor and therefore is not
identified as a medium of concern at this operable unit. Coordination of East Harbor activities with
work at the two Wyckoff operable units is critical to successful sediment remediation and is factored
into the phasing of East Harbor remedial actions.
Although they are not considered environmental media, fish and shellfish tissues are of interest in
Eagle Harbor as indicators of exposure of ecological receptors to contaminated sediments. Also,
contaminated seafood may be consumed by the public. Mercury and PAH concentrations in fish and
shellfish tissue from Eagle Harbor indicate elevated concentrations of the contaminants of concern
relative to uncontaminated areas of Puget Sound.
6.6 Depth of Concern
The depth of concern for protection of the environment is the biologically active zone. In Eagle
Harbor, this zone is defined as the top ten centimeters of marine sediment. RI sediment sampling
focused primarily on contamination in these surface sediments. Sampling to evaluate the depth of
contaminated sediment was limited, particularly in the West Harbor, where contamination arrived
through surface transport. In the East Harbor, more extensive work was completed tocassess potential'
subsurface contaminant migration.
While the top ten centimeters is where remedial action objectives must be met to minimize the
exposure of marine organisms to the contamination, volume estimates for dredging alternatives took
into account the precision of available dredging technologies and the need to leave clean sediments
exposed after dredging.
Contamination in the East Harbor appears to be concentrated in the upper meter of sediments but has
been found at lower concentrations at depths up to 20 feet in borings collected close to the Wyckoff
Facility (Technical Memorandum No. 11). At the edge of the intertidal zone north of the Facility,
visible contamination was noted sporadically at depths up to 60 feet (CH2M Hill, March 1994).
6.7 Routes of Migration
PAH and mercury in the environment tend to adsorb to soils or sediments, particularly if they contain
high organic carbon content. Modeling of the fate and transport of sediment-bound contamination
was conducted during the RI/FS.
In the East Harbor, subtidal areas were identified where propeller wash (generated primarily by
ferries waiting at the terminal) creates high water velocities near the harbor bottom (Figure 10). In
these areas, fine sediments and any attached contaminants can be mobilized and, depending on the
-25-
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NPE69206.02.(M/Areas ol Ferry Prop lnll./8-4-94/lKW
FERRY
TERMINAL
FERRY
MAINTENANCE
FACILITY
Bottom Velocities:
* 45 em/sec
30 cm/sec
20 cm/sec
15 cm/sec
12 cm/sec
10 cm/sec
WYCKOFF
FACILITY
Noto: 1 through 6 Indicate number of
boat lengths behind ferry.
Scale In Meters
Figure 10
AREAS OF FERRY
PROPELLER INFLUENCE
-------
direction of predominant currents, may settle further into the harbor or out of the harbor mouth.
Coarser-grained material stirred up by propeller-induced currents would not be transported a
significant distance but would resettle in the same general area.
On steep slopes or in shallow areas with active boat traffic, movement of contaminated particles may
contribute to contaminant migration. In intertidal areas, wave action can suspend fine sediments and
in some locations moves larger particles. This is the case for Rockaway Beach, outside the harbor
mouth, where currents tend to move particles along the shoreline toward the harbor.
Mercury and PAHs can also be distributed in the environment through uptake by plant and animal
species and accumulation in tissues; for mercury, this requires the microbial transformation of
inorganic mercury into bioavailable forms. PAHs, although generally metabolized by vertebrates, can
accumulate in invertebrate tissues. While metals do not break down, PAHs are subject to
photodegradation, chemical decay, and microbial action. These breakdown processes are most
effective in intertidal areas, due to the aerobic conditions and exposure to sunlight. Breakdown rates
differ among the PAHs and tend to be fastest for the LPAHs.
In summary, in the absence of sediment remediation, contaminant transport pathways are likely to
continue to redistribute contamination in sediments and biota in and near the harbor, through sediment
transport and biological uptake.
6.8 Potentially Exposed Populations
Human populations potentially exposed to contamination include children and adults who consume
contaminated fish and/or shellfish, and individuals, particularly children, who might b$ exposed to
contaminated intertidal sediments through dermal exposure (skin contact) or incidental ingestion.
Waterfront residences, a public park, and fishing piers provide access to potentially contaminated
intertidal beaches and harvestable seafood.
Marine organisms potentially exposed to contaminated sediments include sediment-dwelling organisms
in three major taxonomic groups: mollusca (e.g., clams), polychaeta (worms), and Crustacea (e.g.
amphipods). Marine animals such as bottom-feeding fish and crabs are exposed to both contaminated
sediments and contaminated prey organisms. Animals higher in the food chain may in turn be
exposed. Thus, although the biological tests may indicate impacts to specific sediment-dwelling
organisms, these organisms are a building block of the marine ecosystem. Adverse effects at this
level signal potential impacts on the overall health of the harbor.
6.9 Principal Threat
The NCP (Section 300.430(a)(l)) outlines expectations for Superfund actions to address "principal
threats" through treatment. Principal threats include wastes with high concentrations of toxic
compounds (e.g., several orders of magnitude above levels that allow for unrestricted use and
unlimited exposure). EPA has defined sediments containing free-phase oily contamination as the
principal threat in the East Harbor. Free-phase oily contamination contains very high levels of PAHs.
Near the surface it becomes available to marine organisms and may be remobilized by biological
activities or other disturbances of surface sediments.
-27-
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7. SUMMARY OF SITE RISKS
CERCLA response actions at the East Harbor operable unit as described in this ROD are intended to
protect the marine environment and human health from risks related to current and potential exposure
to hazardous substances in the East Harbor.
To assess the risk posed by site contamination, EPA completed human health and environmental risks
assessments as part of the Eagle Harbor RI. Additional information gained during the preparation of
the FS was incorporated in a Revised Risk Assessment for human health. Although risks were
assessed for the harbor as a whole, this section emphasizes results from the East Harbor.
7.1 Human Health Risk Assessment
Cancer and noncancer risks to human health were evaluated using chemical data from Eagle Harbor
and background areas. Table 3 shows the potential exposure pathways evaluated. Other exposure
pathways considered were eliminated because risks associated with these routes were not expected to
add significantly to human health concerns related to the site.
Human exposure to contamination was considered of concern in intertidal areas, because dermal
contact with and ingestion of contaminated sediments is possible. Consumption of contaminated fish
and shellfish harvested in Eagle Harbor was also of concern. For this reason, risks from four
exposure routes were calculated, including ingestion of contaminated clams and crabs, ingestion of
contaminated fish, ingestion of contaminated intertidal sediments, and dermal contact with
contaminated intertidal sediments.
7.1.1 Identification of Chemicals of Concern
Sixty-five chemicals were detected in intertidal sediments and/or fish and shellfish. The risk
assessment identified 42 of these as chemicals of potential concern for human health, based on the
frequency and magnitude of measurements in sediments and seafood from Eagle Harbor. Of these,
13 were eliminated because sufficient information was lacking to characterize the risk or because the
concentrations observed did not add significantly to the total risk. The remaining 29 chemicals (Table
4) were carried forward for calculations of risk.
7.1.2 Toxicity Assessment
Toxicity information was provided in the risk assessment for the chemicals of concern. Generally,
cancer risks are calculated using toxicity factors known as slope factors (SFs), while noncancer risks
rely on reference doses.
SFs have been developed by EPA's Carcinogenic Assessment Group for estimating excess lifetime
cancer risks associated with exposure to potentially carcinogenic contaminants of concern. SFs are
expressed in units of (mg/kg-day)'1 and are multiplied by the estimated intake of a potential
carcinogen, in mg/kg-day, to provide an upper-bound estimate of the excess lifetime cancer risk
-28-
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Tabli 3
Potential Exposure Pathways Retained for Risk Assessment
Contaminated
Media
Intertidal sediments
Intertidal sediments
Intertidal sediments
)
Shellfish
Shellfish
Shellfish
'Pelagic or bottomfish
Exposure Point
Residential beaches
Industrial beaches
Public beaches
Residential beaches
Industrial beaches
Public beaches
Deeper waters within
Eagle Harbor
Exposure Route
Ingestion
Dermal absorption
Ingestion
Dermal absorption
Ingestion
Dermal absorption
Ingestion
Ingestion
tngestion
Ingestion
Potential Receptors
Residents
Workers or visitors
General public
Residents
Workers or visitors
General public
General public
Rationale
Beaches readily accessible to residents
and visitors.
Beaches readily accessible to workers and
visitors.
Beaches readily accessible to public.
Beaches readily accessible to residents
and visitors. Clams exist at beaches.
Beaches readily accessible to workers and
visitors. Clams exist at beaches.
Beaches readily accessible to public.
Clams exist at beaches.
Presence of fish and recreational
fishermen.
-------
o
Table 4 |
Chemicals of Potential Concern for Human Health
Chemicals Retained^
Chemicals Excluded
Semivolatile Compounds
Bis(2*ih'ylhexyf)phUi«lale
Dibenzofuran
J>»fl&ehloroph»n61
2,3,43-Tttrachlorophenol
Benzole acid 2,4,5-Trichlorophenol
2-Methylphenol
4-Methylphenol
Polycyclic Aromatic Hydrocarbons (PAH)
ma^xm
Acenaphthylene
Anthracene
BinzotaJsnChrMini
pEnzo(a)pyren&
6«/»zotb](lu«atBh«n«
Benzo[g,h,i)perylene
BenziKkJ fluorantKeSe
Qity«4B4
p*b£nW.M«
-------
associated with exposure at that intake level. The term "upper bound" reflects the conservative
estimate of the risks calculated from the SF. Use of this approach makes underestimation of the
actual cancer risk highly unlikely. SFs are derived from the results of human epidemiological studies
or chronic animal bioassays to which animal-to-human extrapolation and uncertainty factors have been
applied (e.g., to account for the use of animal data to predict effects on humans.)
Reference doses (RfDs) have been developed by EPA for indicating the potential for adverse health
effects from exposure to contaminants of concern exhibiting noncarcinogenic effects. RfDs, which
are expressed in units of mg/kg-day, are estimates of lifetime daily exposure levels for humans,
including sensitive individuals. Estimated intakes of contaminants of concern from environmental
media (e.g., the amount of a contaminant of concern ingested from contaminated drinking water) can
be compared to the RfD. RfDs are derived from human epidemiological studies or animal studies to
which uncertainty factors have been applied.
The risk assessment relied on oral SFs and RfDs. Because dermal toxicity factors have not been
developed for the chemicals evaluated, oral toxicity factors were used in estimating noncancer risks
from dermal exposure. The noncancer toxic endpoints (e.g., the affected organs) are similar for
dermal and oral exposure. As this is not the case for dermal and oral cancer endpoints, cancer risks
from dermal exposure could not be calculated. The toxicity factors, shown on Table 5, were drawn
from the Integrated Risk Information System (IRIS) or, if no IRIS values were available, from the
Health Effects Assessment Summary Tables (HEAST). The oral SF of benzo(a)pyrene was used for
all seven carcinogenic PAHs in estimating cancer risks from ingestion pathways. This approach is
intended to address uncertainties in the toxicity of the remaining six PAHs.
771.3 Exposure Assessment
The exposure assessment identified potential pathways for contaminants of concern to reach the
exposed population. Exposure assumptions were based primarily on EPA regional and national
guidance, except where tailored to specific site conditions (Table 6).
A 1988 Puget Sound Estuary Program (PSEP) study of seafood consumption in Puget Sound CTetra
Tech, 1988) provided a high (95th percentile) Puget Sound consumption rate of 95.1 grams per day
of fish. This rate corresponds to 230 servings of 1/3-lb of fish over the course of a year. The high
rate for shellfish consumption was estimated to be 21.5 g/day, equivalent to a 1/3-lb serving a week.
(The study estimated that an average consumer eats at most 30 such servings of fish and three such
servings of shellfish per year).
The high rates above were used for the reasonable maximum exposure (RME) assumption for adults.
These assumptions were modified to develop ingestion rates for children, based on body weight
ratios. Soil ingestion and site-specific dermal exposure assumptions were also developed.
For carcinogens, risks are estimated as the incremental probability of an individual developing cancer
over a lifetime as a result of exposure to the carcinogen. Excess lifetime cancer risk is calculated by
multiplying the SF (see toxicity assessment above) by the "chronic daily intake" developed using the
exposure assumptions. These risk are probabilities generally expressed in scientific notation (e.g., 1
x 10"6). An excess lifetime cancer of 1 x 10"* indicates that an individual has a 1 in 1,000,000 chance
-31 -
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Table S Human Toxicity Factors of Chemicals Retained for Risk Quantification
COMPOUND
Semivolntile Compounds
Bis(2-clhylhcxyl)phlhalatc
Pcntachlorophenol
Phenol
Pulyuuclear Arouiatk Hydrocarbons
Accnaphlhene
Anthracene
Benzo(a)anthraccne
Banzo(a)pyrcne
Bcnzo(b)fluoranlhcne
BenzoQOfluoranthene
Chrysene
Dibenzo(a,h)anthracene
Fluorafflhene
Indeno(l ,2,3)pyrene
Naphthalene
Pyrene
Nitrogen-Containing Aromatic Compounds
(NCACs)
Carbazole
Quinoline
Volatile Organic Compounds
Chloroform
Chloromethane
Metals
Antimony
Arsenic
Beryllium
Cadmium
Chromium (V[)
Copper
Mercury
Nickel (in soluble salts)
Thallium (in soluble sails)
Zinc
Weight of
Evidence*
B2
82
B2
B2
B2
B2
B2
B2
62
B2
C
B2
C
A
B2
Oral Slope Factor
(mg/kg-day)-'
0.014
0.12
11.5
11.5
11.5
11.5
11.5
11.5
11.5
0.02
12
0.0061
0.013
1.75
4.3
Oral Chronic RfD
(mg/kg-day)-1
0.02
0.03
0.6
0.06
0.3
0.04
0.004
< 0.03
0.01
0.0004
0.001
0.005
0.001
0.005
0.037
0.003
0.02
0.00007
0.2
' EPA Carcinogenic Classification: A = Human Carcinogen, B2 = Probable Human Carcinogen, C = Possible Human Carcinogen
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Table 6 - Exposure Assumptions for Human Health Risk Assessment
Exposure Assumptions for Ingestion of Seafood
Age: 2-3 yr
4-6 yr
7-9 yr
10-12 yr.
13-15 yr
16-18 yr
19-75 yr
Reasonable Maximum Exposure (RME) for Clams and Crabi
IR: Ingestion role (kg/meal)1'"
Ft: Fraction ingested (unillessjF
EF: Exposure frequency (meals/year)'
ED: Exposure duration (years)4
BW: Body weight (kg)'
ATn: Averaging time for noneircinogenic effects (days)1
ATc: Averaging lime for carcinogenic effects (daysjf
0.047'
1
52
2
12
730
27,375
0.059'
1
52
3
17
1,095
27,375
0.076'
1
52
3
25
1,095
27,375
' 0.097'
1
52
3
36
1,095
27,375
0,122'
1
52
3
51
1,095
27,375
0.138'
1
52
3
671
1,095
27,375
0.151'
1
52
57
70
20.805
27,375
Reasonable Maximum Exposure (RME) for Fish
IR: Ingestion rale (kg/meal)*'*
FI: Fraction ingested (unitless)'
EF: Exposure frequency (meals/year)'
ED: Exposure duration (years)'
BW: Body weight (kg)'
ATn: Averaging lime for noncarcinogenie effect! (days)1
ATc: Averaging lime for carcinogenic effect* (dtytf
0.206'
1
52
2
12
730
27,375
0.260*
1
52
3
17
1,095
27,375
0.336'
1
52
3
25
1,095
27,375
0.428'
1
52
3
36
1,095
27,375
0.540*
1
52
3
51
1,095
27,375
0.609'
1
52
3
61
1,095
27,375
0.668'
1
52
57
70
20,805
27,375
Equation for ingestion of fish and shellfish (EPA, July 1989c):
Intake (mg/kg-day) «= concentration (me/kg) x IR x FI x EP X ED
BW x AT
Tetra Tech, 1988.
*P. Cirone, EPA Region 10, personal communication, 1991.
'EPA, July 1989c.
'EPA, January 1990.
The amount ingested was scaled down to the 2/3 power of the ratio of child to adult body weight (P. Cirone, EPA Region 10, personal communication, 1991)
'0.151 kg ahcllfish/meal x 52 meal«/year x 1 year/365 day*, x 1,000 g/kg « 21.5 g/day. This it the high Ingestion rate computed from the Puget Sound «wdy (Tetra Tech, 1988).
0.668 kg fish/meal x 52 meals/year x 1 year/365 day» X 1,000'g/kg *> 95.1 g/d«y. Thli la the high Ingestion rate computed from the Puget Sound itudy (Tetra Tech, 1988).
-------
of developing cancer as a result of site-related exposure to a carcinogen over a 70-year lifetime under
the specific exposure conditions assumed.
The potential for noncarcinogenic effects is evaluated by comparing an exposure level over a specified
time period (e.g., lifetime) with a reference dose (see toxicity assessment above) derived for a similar
exposure period. The ratio of exposure to toxicity is called a hazard quotient. Hazard quotients are
calculated by dividing the chronic daily intake by the specific Rfd. By adding the hazard quotients
for all contaminants of concern that affect the same target organ (e.g., liver), the hazard index can be
generated.
The RME provides a conservative but realistic exposure in considering remedial action at a Superfund
site. Based on the RME, when the excess lifetime cancer risk estimates are below 1 X 10* or when
the noncancer hazard index is less than 1, EPA generally considers the potential human health risks to
be below levels of concern. Remedial action is generally warranted where excess cancer risks exceed
1 X 10"4 (one in ten thousand). Between 10"6 and 10"4, cleanup may or may not be selected,
depending on individual site conditions, including ecological concerns.
Both average and RME risks were estimated for each of the four exposure pathways to show a range
of uncertainty. Because EPA policy dictates the use of the RME in evaluating human health risks,
only RME results are discussed in the following sections.
7.1.4 Risk Characterization
The following discussion presents summarized non-cancer and cancer risk characterization results
separately.
Non-Cancer Risks
The lifetime and child noncancer hazard indices for ingestion of contaminated intertidal sediments
were well below 1. Calculated noncancer risks from dermal contact with PAH-contaminated beach
sediments (using oral exposure Rfds) were significantly below 1 for both lifetime and child exposures.
Clam tissue data from 1988 and 1990 were used to evaluate noncancer risks from consumption of
clams. The 1988 data yielded lifetime hazard indices from 0.6 to 1 for most Eagle Harbor and
background clam sampling locations (for child exposure assumptions, these hazard indices were
between 1 and 2). Because of differences in the mercury results, the highest hazard index based on
1990 clam tissue data was 0.07, lower than the hazard index based on 1988 data.
Noncancer risks were evaluated both for consumption of fish and consumption of shellfish. Data
from 1989 and 1990 fish tissue sampling were used and, as with the clam data, the 1990 results were
lower. Fish tissue data from the 1989 sampling resulted in lifetime hazard indices approaching or
exceeding 1 (up to 2 for the child exposure), while data gathered in 1990 produced hazard indices
considerably less than 1 (and less than 2 for children).
Cancer Risks
Cancer risks from sediment ingestion were within or below EPA's acceptable risk range of 10"4 to
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10"*. As noted, slope factors were unavailable to calculate cancer risks from dermal exposure to
carcinogenic PAHs in sediments.
Two data sets (1988 and 1990) were used in estimating the total excess lifetime cancer risks for
consumption of clams and yielded comparable results. The highest risk of 10~3 was associated with
clams collected from adjacent to the Wyckoff Facility. Background clam tissues collected near the
mouth of Eagle Harbor produced risks from 1 x 10"4 to 5 x IQ4.
A single data set from 1990 was available to evaluate cancer risks from consumption of fish and
crabs. Risk levels depended on the type of tissue (whole fish, fish muscle, crab muscle,
hepatopancreas). The highest risk from this route was 1 x 10° for consumption of whole perch. For
all other tissues, both Eagle Harbor and background samples produced results in the 104 range;
however, the fish tissue data for the PAH contributing most to the risk were qualified as estimates in
these samples.
Summary: The risk assessment discussed uncertainties associated with the calculated risks. Among
the uncertainties are the absence of complete toxicity information for all chemicals measured,
uncertainties and variability in site data, the potential presence in seafood of other contaminants that
may not be site-related, and uncertainties associated with exposure assumptions. The uncertainties
can result either in underestimates or overestimates of the true health risks associated with the site.
In summary, chemical concentrations in Eagle Harbor sediments and seafood are elevated with respect
to background locations. However, human health risk estimates for exposure to sediment
contaminants through dermal contact and sediment ingestion are within or below EPA's range of
acceptable risks. For seafood ingestion, calculated cancer risks are generally between 10"* and 10* at
both Eagle Harbor and background locations. Consumption of shellfish from specific areas (such as
East Harbor areas near the former Wyckoff Facility) results in risks above 10~*. While similar cancer
risk estimates were obtained for tissues such as whole perch, sole muscle, and crab hepatopancreas,
uncertainties in these data should be considered. Noncancer hazard indices for seafood consumption
at both Eagle Harbor and background locations were, as high as 1 based on 1988 data, but subsequent
data resulted in significantly lower values, suggesting similar uncertainties in data.
Human health risks for Eagle Harbor are thus primarily associated with the consumption of
contaminated shellfish. For the East Harbor, specifically, cancer risks in the 10"3 range were
associated with clam tissues from beaches adjacent to the Wyckoff Facility.
7.2 Ecological Assessment
The Eagle Harbor ecological assessment focused on biological effects in subtidal areas. During the
RI, sediment chemical and physical data were collected, laboratory bioassays were conducted on
subtidal sediments, and evaluations of the existing benthic communities were completed. Available
information from previous studies and research was incorporated as appropriate. Although clam
tissue and sediment chemical data were developed for evaluating intertidal areas, the emphasis in
intertidal areas was on evaluating potential human health risks.
The assessment of ecological risks relied on the "triad approach" which links contamination to
specific adverse ecological effects using a preponderance of field and laboratory evidence. The three
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elements of sediment chemical analyses, laboratory toxicity tests (bioassays), and evaluation of the
abundance of benthic organisms from specific locations are used in combination as the three elements
of the triad approach. The approach was used to develop the Puget Sound AETs, and these chemical
concentrations, in conjunction with site-specific biological data, formed the basis of the ecological
assessment in Eagle Harbor.
As described in Section 6, an AET, or "Apparent Effects Threshold," is the concentration of a
chemical in sediment above which a particular adverse biological response has always been observed.
Generally, for any one chemical, different benthic organisms demonstrate biological responses at
different concentrations, leading to a range of AETs (e.g., for benthic effects, amphipod acute
toxicity, oyster larvae acute toxicity, and microtox responses) for each compound (See Table 2,
Section 6).
12.1 Chemicals of Concern
RI sampling of Eagle Harbor sediments included a broad range of metals and organic compounds of
potential concern for environmental risk. Contaminants of concern were identified for the ecological
assessment based on information about their effects in the marine environment. For this reason, not
all were the same as the contaminants of concern identified for human health.
Sediments in Eagle Harbor exceeded the lowest AET (generally for either oyster larvae or microtox)
in most of the contaminated areas. In the East Harbor particularly, sediments exceeded the benthic
AET for at least two individual PAHs at numerous stations. At several locations, all sixteen PAH
compounds exceeded their benthic AETs. Based on the comparison of the concentrations in Eagle
Harbor samples with the 1988 benthic AETs for Puget Sound, EPA selected mercury and all sixteen
PAHs as contaminants of concern. These contaminants are used as indicators of the extent of
contamination. Toxicity information for PAH and mercury was summarized in the ecological risk
assessment.
Contaminants that exceeded AETs at only one or two locations were not carried forward as
contaminants of concern for the ecological risk assessment. Such locations fall within areas of
concern for mercury or PAHs, and cleanup for PAHs and mercury would also address these
contaminants.
12.2 Biological Effects
Laboratory bioassay results from Eagle Harbor samples were grouped by sediment grain size and
were statistically compared with control samples and background samples. The test species used in
amphipod toxicity tests (Rhepoxynius abronius) resides in Puget Sound and is a member of a
crustacean group that forms an important part of the diet of many estuarine fish. Amphipods are
sensitive to many chemical contaminants, and species such as R. abronius have a high pollutant
exposure potential because they burrow into the sediment and feed on sediment material. The oyster
larvae used as a test species (Crassostrea gigas) resides in Puget Sound and supports commercial and
recreational fisheries. The life stages tested (embryo and larva) are very sensitive stages of the .
organism's life cycle. The primary endpoint is a sublethal change in development that has a high
potential for affecting larval recruitment.
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The bioassays for acute toxicity indicated that sediments from many sampled locations in the East
Harbor were toxic to amphipods, oyster larvae, or both. The bioassay responses were most severe in
areas of high PAH contamination, such as areas of the East Harbor north of the Wyckoff Facility.
Bioassays on benthic infauna are valuable indicators because the organisms live in direct contact with
the sediments, are relatively stationary, and are important components of estuarine ecosystems. If
sediment-associated impacts are.not present in the infauna, then it is unlikely that such impacts are
present in other biotic groups such as fish or plankton unless contaminants are bioaccumulating at
levels significant for higher food-chain organisms.
During the RI, samples of benthic infauna were collected to assess the impacts of contamination on
resident benthic communities. As replicates were not collected at each station in Eagle Harbor,
however, statistical comparisons of benthic abundance data between individual stations were not
possible. Overall, there was a greater abundance of polychaetes in Eagle Harbor than in the
background areas, which could indicate a predominance of pollution tolerant organisms. However,
no statistically significant difference in abundance relative to background areas was observed for
molluscs, amphipods, and other Crustacea.
Other benthic studies of Eagle Harbor tend to support the indication in the RI that, while sediment
contamination is present above the benthic AET for large areas of the harbor, adverse effects on
benthic communities at the level of major taxa (polychaeta, molluscs, amphipods, other Crustacea)
may not be occurring except in the more heavily contaminated areas close to the Wyckoff Facility.
Additional evidence of biological effects in Eagle Harbor includes the prevalence of liver lesions and
tumors in English sole, as documented by NOAA (Malins, 1985). The high incidence of such effects
in Eagle Harbor relative to other Puget Sound embayments was confirmed in the Puget Sound
Ambient Monitoring Program 1991 sampling. This and laboratory research citing the effects of PAH/
and other sediment contaminants on marine organisms add to the preponderance of evidence already
indicating potential damage to Eagle Harbor marine life. In addition, PAH and metals in the tissues
of fish and shellfish indicate uptake of sediment contamination. Mercury tends to bioaccumulate in
fish, while PAHs can. bioaccumulate in some invertebrates.
Uncertainty in the ecological risk assessment is associated with data variability, spatial variability of
contamination and benthic communities, potential biological effects of organic enrichment, grain size,
and physical disturbance, and the availability of appropriate background locations for comparison.
In summary, ecological risks due to contamination in the East Harbor are evidenced by documented
acute toxicity of sediments near the former wood treating facility, by the predicted toxicity of other
sediments with contaminant concentrations above AETs, and by the presence of mercury and PAHs,
which can accumulate in the tissues of food chain organisms.
7.3 Summary of Risk Assessment
Actual or threatened releases of hazardous substances from this site, if not addressed by implementing
the response action selected in this ROD, may present an imminent and substantial endangerment to
public health or welfare, or the environment.
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Based on the RI, the risk assessments, and available information, cleanup of the East Harbor is
warranted. Consumption of shellfish from intertidal locations of the East Harbor adjacent to the
Wyckoff Facility pose a human health risk above the acceptable risk range. Sediment cleanup is
expected to result in reductions of contaminant levels in fish and shellfish, and over the long term,
sediment cleanup and natural recovery may eventually reduce risks to levels comparable to
background.
Adverse biological effects were documented in much of the East Harbor. Most of the biological
effects previously observed were associated with heavy sediment contamination. Potential
redistribution of contaminants through sediment redistribution from these heavily contaminated areas
was also of concern, as well as the potential for uptake by marine organisms. These heavily
contaminated areas were addressed by the cap completed as the first phase of cleanup, under
CERCLA removal authorities. Other areas of the East Harbor contain levels of contamination
predicted to cause minor or, in some areas, significant biological effects. Cleanup is warranted to
address sediments where significant biological effects are predicted, unless biological data indicating
the absence of such effects is obtained.
7.4 Special Site Characteristics
Investigation and remediation of sediment contamination pose inherent challenges, as briefly indicated
below:
the accumulation of contaminants at the sediment-water interface, a significant zone for habitat
and food sources, creates complex and sensitive ecological conditions and can lead to
contaminant transfers through the food chain;
contaminants that accumulate in sediments are generally dispersed from their sources,
resulting in relatively large areas of low level contamination;
surface sediment contamination reflects both historical and on-going contamination, because
marine biological activity in the biologically active top layer mixes recently deposited
sediments with existing sediments and because physical disturbances such as currents or
propeller wash can redistribute surface contamination;
the relatively large volumes of sediments requiring remediation can present problems
regarding disposal site availability and capacity; and
underwater conditions compound the technical challenges associated with assessing,
controlling, and remediating contamination of environmental media.
Remediation of Eagle Harbor sediments is further complicated by the active use of the harbor.
Cleanup activities will require coordination and planning in nearshore areas, subtidal leased lands, and
the navigational pathways used by the Washington State Ferries. These and other special features of a
marine sediment site have been considered in the RI/FS and this ROD.
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8. DESCRIPTION OF ALTERNATIVES
This section briefly summarizes key elements of the FS (November 1991), including the identification
of cleanup areas in the East Harbor, the screening of alternatives, and the development of individual
alternatives for the East Harbor, including cost estimates and time frames. Descriptions of the
alternatives are provided in Section 8.4.
The FS identified cleanup alternatives for sediments in intertidal and subtidal areas of Eagle Harbor,
including technologies effective for PAH contamination, for metals contamination, and for both. The
alternatives spanned a range of costs and complexity, from no action to treatment. For East Harbor
sediments, where the predominant contaminants are PAHs, seven alternatives were carried forward
for detailed evaluation, including the no action alternative as required. Six other alternatives were
eliminated for East Harbor sediments due to issues of effectiveness, waste characteristics, process
complexity, implemehtability, and the availability of more suitable options. Table 7 lists all of the
alternatives considered and identifies those carried forward for East Harbor sediments.
8.1 Applicable or Relevant and Appropriate Requirements
Remedial actions implemented under CERCLA must meet legally applicable, or relevant and
appropriate requirements (ARARs). ARARs include environmental requirements, criteria, standards,
and other limitations promulgated by federal, state, and tribal governments. Other factors to be
considered (TBCs) in remedy selection and implementation may include nonpromulgated standards,
criteria, advisories, and guidance, but TBCs are not evaluated pursuant to the formal process required
for ARARs. Local ordinances with promulgated criteria or standards.are not considered ARARs, but
may be important TBCs.
The Sediment Standards, described in Section 6, are a primary ARAR for this site, and are used in
defining the overall site cleanup objective. Clean Water Act Sections 401 and 404, relating to
dredging and fill activities in the waters of the United States, are potential ARARs for all active
remedial alternatives. Compliance with these ARARs would require monitoring of water quality
during dredging or capping, and would involve habitat mitigation if the cleanup results in an
unavoidable loss of aquatic habitat. Section 10 of the federal Rivers and Harbors Act, as well as the
state Hydraulic Code Rules and Shoreline Management Act could also be ARARs for active
alternatives.
Other potential ARARs are associated with specific alternatives. RCRA and the State of Washington
Dangerous Waste Regulations could apply for on-site alternatives involving disposal of sediments.
For consolidation and containment without treatment within an area of contamination these would not
be applicable but could be relevant and appropriate. For alternatives involving dredging and
treatment of East Harbor sediments, these laws would be applicable for sediments determined to be
dangerous or hazardous wastes. For in situ alternatives, such as Capping, No Action, and
Institutional Controls, these regulations would not be ARARs.
Discharges of wastewater generated by dredging or treatment of the sediments could be subject to the
state Water Pollution Control Act and Water Quality Standards, as well as the National Pollution
Discharge Elimination System (NPDES). For wastewater discharged to a publicly-owned treatment
works, the state Waste Discharge Permit Program could apply. For alternatives with potential air
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Table 7
Screening of Alternatives
Alternative
East Harbor
PAH Areas
Intertidal
Sediments
Subtidal
Sediments
A. No Action/Natural Recovery
6. Institutional Controls/Natural Recovery
Capping
Removal, Consolidation, and Confined Aquatic
Disposal
E. Removal, Consolidation, and Nearshore Disposal
Removal,
-a
H. Removal, Treatment by Incineration, and
Disposal
\% %H ^ ' ' ,, -f'-
1. Uentovaf/Treatriiest $y;
'tV*t$n&&S$
' ' - - \ ^ r>- "7K5>jf s ^fV^"
K.
Removal,
Disposal
Removal, Treatment by Biological Slurry, and
Disposal
M.
In Situ Solidification/Stabilization
Alternative carried forward for area indicated.
Not carried forward.
-40-
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releases, such as incineration, the federal Clean Air Act and Puget Sound Air Pollution Control
Agency regulations are potential ARARs.
8.2 Estimated Cleanup Areas
As described in Section 3.5, part of the East Harbor was covered with a clean sediment cap after
completion of the RI/FS and issuance of the 1991 Proposed Plan. This section describes remaining
East Harbor areas which may require cleanup, as proposed in the 1994 Proposed Plan, and explains
the relationship between these areas and areas used to develop FS cost estimates.
The Sediment Standards provide a process for defining sediment cleanup sites by comparing site
chemical data to chemical criteria. As shown in Tables 8 and 9, the Sediment Standards provide two
levels of biological and chemical criteria, the more stringent level corresponding to the sediment
quality standards (SQS), below which sediments pose no significant risk and do not require further
study, and the less stringent level corresponding to the minimum cleanup level (MCUL), above which
cleanup must be considered. Between the two levels, chemical concentrations are associated with
minor adverse biological effects. Collection of biological data is optional, but if specific biological
information is collected, comparison of these results to the biological criteria of the Sediment
Standards determines whether or not sediments meet the Sediment Standards. At least three different
biological measurestwo acute and one chronic-are required for comparison to the biological criteria.
Figure 11 shows Eagle Harbor sediments contaminated above the chemical criteria for one or more of
the contaminants of concern based on RI/FS data. A larger area exceeds the more stringent SQS
chemical criteria than the MCUL chemical criteria. Table 10 provides estimated areas of East Harbor
subtidal surface sediments with contaminant concentrations above the MCUL chemical criteria and .the
more stringent SQS chemical criteria. Figure 11 also shows the existing cap in the East Harbor. The'
cap was placed over areas where subtidal sediments failed bom chemical and biological criteria at the
MCUL level, indicating significant adverse biological effects in these areas.
Because biological tests were performed at Eagle Harbor before the Sediment Standards were
promulgated, available biological data for remaining areas of the East Harbor cannot be compared to
the Sediment Standards biological criteria with the completeness necessary to override chemical
results. Biological data collected during the RI/FS can be compared to two. acute toxicity criteria of
the Sediment Standards, but data on chronic biological effects are not sufficient for comparison to a
third, chronic criterion. Thus, remaining potential cleanup areas in the East Harbor are defined based
on the comparison of chemical data to the Sediment Standards.
Cleanup areas estimated in the FS prior to completion of the cap are also shown in Table 10. These
estimates were used to support FS cost estimates and were developed based on an interpretation of
both chemical and biological data, rather than chemical data alone. As shown in Table 10, the FS
area estimates are comparable to the remaining cleanup areas based on chemical criteria alone. For
this reason, existing FS cost estimates can be used in the evaluation of cleanup alternatives for the
remaining subtidal areas defined by the MCUL and SQS chemical criteria.
^
For intertidal PAH areas, the FS developed cost estimates for the combined East and West Harbor.
The East Harbor area estimate is listed in Table 10. Cleanup costs for intertidal areas in the East
Harbor only would be approximately two thirds of the FS cost estimates.
-41 -
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Table 8
Sediment Standards Chemical Criteria
for Mercury and PAH1
Contaminant
Mercury
Individual PAIis and PAH groups
LPAH5
Naphthalene
Acenaphlhylene
Acenaphthene
Fluorene
Phenanthrene
Anthracene
2-Methylnaphthalene
HPAH'
Fluoranlhene
Tyrone
Benz(a)anthracene
Chrysene
Total benzofluoranthenes7
Benzo(a)pyrene
Indeno(l ,2,3-c,d)pyrene
Dibenzo(a,h)anthracene
Benzo(g,h,i)perylene
SQS1
0.41 mg/kg (dry weight)
units of mg/kg organic carbon*
370
99
66
16
23
100
220
38
960
160
1,000
110
110
230
99
34
12
31
MCULJ
O.S9 mg/kg (dry weight)
units of mg/kg organic carbon4
780
170
66
57
79
480
1,200
64
5,300
1,200
1,400
270
460
450
210
88
33
78
1 Where laboratory analysis indicates a chemical is not detected in a sediment sample, the detection limit shall be reported and shall be
at or below the criteria value shown in this table. Where chemical criteria in this table represent the sum of individual compounds or
isomers, and a chemical analysis identifies an undetected value for one or more individual compounds or isomers, the detection limit
shall be used for calculating the sum of the respective compounds or isomers.
2 Sediment Quality Standards
1 Minimum Cleanup Level
4 The listed chemical parameter criteria represent concentrations in parts per million, "normalized," or expressed, on a total organic
carbon basis. To normalize to total organic carbon, the dry weight concentration for each parameter is divided by the decimal
fraction representing the percent total organic carbon content of the sediment.
3 The LPAH criterion represents the sum of the following "low molecular weight polynuclear aromatic hydrocarbon" compounds:
Naplhalene, Acenaphthylcne, Acenaphthene, Fluorene, Phenanthrene, and Anthracene. The LPAH criterion is not the sum of the
criteria values for the individual LPAH compounds as listed.
* The HPAH criterion represents the sum of the following "high molecular weight polynuclear aromatic hydrocarbon" compounds:
Fluoranlhene, Pyrene, B«nz(a)anthracene, Chrysene, Total Benzofluoranthenes, Benzo(a)pyrene,lndcno(l,2,3,-c,d)pyrenc,
Dibenzo(a,h)anthracene, and Benzo(g,h,i)pcrylene. The HPAH criterion is not the sum of the criteria values for the indivisual
HPAH compounds as listed.
7 The TOTAL BENZOFLUORANTHENES criterion represents the sum of the concentrations of the "B," "J," and "K" isomers.
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Table 9
Sediment Standards Biological Criteria
SQS" Biological Criteria
MCULb Biological Criteria
Sediments arc determined to have adverse effects on
biological resources when any one of the confirmatory
marine sediment biological tests of WAC 173-204-
315(1) demonstrate the following results:
(a) Amphipod: The test sediment has a higher0 mean
mortality than the reference sediment and the test
sediment mean mortality exceeds 25%, on an absolute
basis.
(b) Larval: The test sediment has a mean survivorship
of normal larvae that is less* than the mean normal
survivorship in the reference sediment and the test
sediment mean normal survivorship is less than 85%
of the mean normal survivorship in the reference
sediment (i.e., the test sediment has a mean combined
abnormality and mortality that is greater than 15%
relative to time-final in the reference sediment).
(c) Benthic abundance: The test sediment has less than
50% of the reference sediment mean abundance of any
one of the following major taxa: Crustacea, Mollusca,
or Polychaeta, and the test sediment abundance is
statistically different* from the reference sediment
abundance.
(d) Juvenile polychaete: The test sediment has a mean
biomass of less than 70% of the reference sediment
mean biomass and the test sediment biomass is
statistically different' from the reference sediment
biomass.
(e) Microtox: The mean light output of the highest
concentration of the test sediment is less than 80% of
the reference sediment, and the two means are
statistically different.
The MCUL is exceeded when any two of the
biological tests exceed the SQS biological criteria; or
one of the following test determinations is made:
(i) Amphipod: The test sediment has a higher* mean
mortality than the reference sediment and the test
sediment mean mortality is more than 30% higher
than the reference sediment mean mortality, on an
absolute basis.
(ii) Larval: The test sediment has a mean survivorship
of normal larvae that is less1 than the mean normal
survivorship in the reference sediment and the test
sediment mean normal survivorship is less than 70%
of the mean normal survivorship in the reference
sediment (i.e., the test sediment has a mean combined
abnormality and mortality that is greater' than 30%
relative to time-final in the reference sediment).
(iii) Benthic abundance: The test sediment has less
than 50% of the reference sediment mean abundance
of any two of the following major taxa: Crustacea,
Mollusca, or Polychaeta and the test sample
abundances are different' from the reference
abundances.
(iv) Juvenile polychaete: The test sediment has a
mean biomass of less than 50% of the reference
sediment mean biomass and the test sediment biomass
is statistically different0 from the reference sediment
biomass.
' Sediment Quality Standards
b Minimum Cleanup Level
' Statistical Significance is defined with a test, p less than or equal to 0.05.
Test results from at least two acute effects tests and one chronic effects test shall be evaluated. The biological
tests shall not be considered valid unless test results for the appropriate control and reference sediment samples
meet the performance standards described in WAC 173-204-315(2).
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NPE692oe.03.
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Table 10
Area Estimates for the East Harbor
Potential Cleanup Area
Remaining Subtidal PAH Areas'
above the MCUL
above the SQS
Subtidal PAH Areas Estimated in FSb
Lower-bound estimate
Upper-bound estimate
FS Intertidal PAH Areac
Area
(square
meters)
259,000
488,000
235,000
420,000
35,000
Area
(acres)
64
121
58
103
9
These areas are derived by comparison of RI data to the Sediment Standards chemical criteria, after
the 222,000 mz area (55 acres) subsequently covered by the existing cap is deducted.
b FS areas were developed prior to the existing cap, using the same RI chemical data but reflecting EPA
interpretation of available RI biological data. These are the basis for cost estimates in Table 12B.
c PAH intertidal areas were estimated separately in the FS for East Harbor and West Harbor sediments.
The combined areas are the basis for estimated costs of the remedial alternatives in Table 12A.
As noted above, available biological data did not allow comparison to the Sediment Standards
biological criteria for the full complement of three biological measures. Figure 12 shows the results
Of. the two acute toxicity tests completed during the RJ/FS, relative to the SQS and MCUL biological
criteria (Table 9). As shown, some areas with contaminant concentrations above the MCUL
demonstrated minor or no acute effects in acute toxicity testing. If further testing shows that such
areas meet all three biological criteria, they will not require cleanup under the Sediment Standards.
Without this testing, however, cleanup areas must be based on chemical data only.
8.3 Common Components of Alternatives
A number of remedial alternatives evaluated in the FS share certain components. Table 11 shows
which elements are common to alternatives considered for the East Harbor. Further detail is provided
in the FS. Potential navigational constraints were considered for all of the active remedial
alternatives.
The following elements are also important to all of the alternatives:
-institutional controls
-source control
-natural recovery
-sampling during remedial design
-monitoring during and after cleanup
A brief discussion of each is provided in the following sections.
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i A Anphipod / 6-5-94 / CJS / LKW
CITY OF
BAINBRIDGE ISLAND
-\
f U8UC PARK
AND DOCK
FERRY
TERMINAL
/FORMER
SHIPYARD
658
?sft
NOTE; West Harbor
problem areas are not
addressed in this ROD.
787 *''-'"
'
v^, ; -j, *?
WESTH^RBbRc
150 300 600
Scale in Meters
)U
WYCKOFF
FACILITY
LEGEND
Exceeds MCUL chemical criteria
O Oyster larvae and amphlpod bioassays pass both SQS and MCUL ^
A Oyster larvae bioassay (alls SQS only/Amphlpod bloassay passes both SQS and MCUL
a Oyster larvae bloassay falls both SQS and MCUL/Amphlpod bloassay passes both SQS and MCUL
O Oyster larvae bioassay fails both SOS and MCUL/Amphlpod bloassay falls SQS only
Oysler larvae and amphipod bioassays fail both SQS and MCUL
Figure 12
COMPARISON OF EAGLE HARBOR JUNE 1988
SUBTIDAL OYSTER LARVAE AND AMPHIPOD
BIOASSAY RESULTS TO WASHINGTON STATE
SEDIMENT STANDARDS
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8.3.1 Institutional Controls
Institutional controls are controls on the use of a site. They are generally intended to limit human or
environmental exposure to contaminants or to protect completed cleanups.
For the East Harbor, institutional controls alone were .considered as an individual alternative
(Alternative B), consisting of continuation of the existing health advisory, fencing and additional
warnings on the beach adjacent to Wyckoff Facility, community outreach, and seafood monitoring.
Institutional controls would likely be necessary in conjunction with active remedial alternatives,
because the design and implementation of cleanup would take several years and corresponding
reductions in seafood contaminant levels could take still longer.
Institutional controls could also be necessary to prevent disturbance or damage to completed or
ongoing cleanups. For example, limits on anchoring, dredging, or other sediment disturbance could
be necessary for containment alternatives which leave contamination on site.
83.2 Source Control
Source control is an important element of any cleanup. For the East Harbor further source control is
necessary prior to final sediment remediation. East Harbor sediment cleanup alternatives include
monitoring to verify source control. However, they do not include efforts to control sources of
contamination from other areas of the site.
In general, sources to sediments may include discharges, runoff, or spills directly to beaches or
surface water, as well as releases through more indirect pathways such as groundwater transport,
seepage, air deposition, or movement of contaminated sediments from one area to another. For East
Harbor sediments, the chief source of contamination is the inactive Wyckoff Facility, and the bulk of
sediment contamination is likely due to past operations. Oily seepage on the beach has been reduced
by ongoing cleanup efforts, and additional cleanup at the Facility is likely under an interim
groundwater ROD and a final ROD for soil and groundwater. These actions are expected to control
continuing sources of contamination over the next three to six years.
The West Harbor is a probable continuing source of mercury contamination to the East Harbor.
Implementation of sediment cleanup pursuant to the West Harbor ROD (1992) is anticipated to
eliminate sources of mercury to the East Harbor.
8;3J Natural Recovery
The Sediment Standards allow mathematical modeling as a means to identify areas which, through
natural recovery, would meet cleanup objectives without active remediation. These areas may then be
designated as sediment recovery zones and monitored to verify predicted recovery.
Cleanup areas in Table 10 are based on conditions at the time of RI/FS data collection, without
designation of sediment recovery zones. However, under the Sediment Standards, No Action and
Institutional Controls would require designation of sediment recovery zones unless used in
combination with active remedial alternatives. Even if active cleanup were selected, sediment
recovery zones could be designated. The siterspecific objective could incorporate a natural recovery
period or could identify a basis for selecting natural recovery in specific areas. Ten years is generally
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OO
I
Table ) 1
Summary of Common Components for East Harbor Remedial Alternatives
Alternative
A. No Action
I). Institutional Control)*
C. Capping
D. Removal, Consolidation,
and Confined Aquatic
Disposal
U. Removal, Consolidation,
and Neanvhore Disposal
H. Removal, Treatment by
Incineration, and Disposal
L. Removal, Treatment by
Biological Slurry, and
Diipoiel
Type of Dredging,
Excavation, or Mixing
Mechanical
Hydraulic
»
Turbidity
Control
.
Temporary Nearahore
Sediment Storage*
Treatment at
Wyckoff Property
t
Pretreaunenl
Debris
Removal
»
Sediment
Resizing
Dewatcring
Storage and Treatment
of Wajtewater
»
5-year review .
Mandated by CERCLA1
»
'It has been assumed that imported nil for the intcrtidal cop would be mechanically placed.
Ml ha* been atiumed (hot clean sediment Tor the lublidal cap would be hydraulieallydredged.
It hki been aitumed that the CAD pit would be hydraulicallydredged.
1l ha> been assumed that the cap would be hydnmlieally dredged (excluding the lurface layer that would be imported fill).
'If only a (mall volume of «ediment ii treated, temporary neanhore «edimenl itorage may not be needed.
''fhe S-year review would be conducted with all altemativea.
- Component is included in alternative.
-------
used as a reasonable time frame for natural recovery, starting when significant contaminant sources
are controlled. A longer period can also be authorized.
EPA conducted mathematical modeling during the RI/FS to evaluate the potential for natural recovery
of contaminated Eagle Harbor sediments within ten years of source control. The evaluation and
technical references may be reviewed in Appendix Dl of the FS. Briefly, the model used RI/FS data
to represent sediment contaminant levels at the tune of contaminant source control, and available
information from the scientific literature was used to estimate PAH degradation rates, loss by
advection (sediment movement), and other natural processes. Sedimentation rates were estimated
based on a watershed model (see Table 1, Technical Memorandum #4, 1989). Since Eagle Harbor is
not fed by a river or other significant upland sources of sediment, estimated sedimentation rates were
relatively low.
Key references for degradation rates included Cerniglia and Heitcamp (1989), Lee and Ryan, (1983)
and Payne and Phillips (1985). The studies indicated that degradation of PAHs is enhanced by
exposure to ultraviolet or visible light, that LPAHs tend to break down faster than HPAHs due to
their solubility, that high concentrations of PAHs inhibit breakdown rates, and that aerobic conditions
tend to enhance microbial breakdown processes. Thus, once sources are controlled, PAH degradation
is likely, to be fastest hi sediments exposed to light, biological mixing, and wave action, or in areas
where contaminants are at low to moderate levels in only the biologically mixed surface layer. Since
metals are not degradable, natural recovery of metals-contaminated sediments would rely on
sedimentation, advection, and other natural processes.
Based on the natural recovery evaluation in the FS, areas north of the Wyckoff Facility containing
heavy PAH contamination and some metals contamination were not predicted to achieve the Sediment
Standards without active remediation. However, less contaminated subtidal areas withput metals
contamination had some potential to achieve the Sediment Standards for PAHs within ten years, once
sources of contamination were controlled. Natural recovery was predicted to be most effective in
intertidal areas containing PAHs, due to the active water regime and exposure of sediments to light
and air. Based on limited data and assumptions, these estimates of natural recovery are approximate
and would require verification through monitoring.
83.4 Sampling During Remedial Design
Although extensive source, chemical, and biological information was collected during the RI/FS and
previous studies of Eagle Harbor, additional sampling is likely to be needed during remedial design.
Remedial design sampling would be used to refine actual cleanup areas and volumes for design
purposes and is included for all alternatives other than No Action and Institutional Controls. In the
East Harbor, EPA expects that ongoing processes hi the marine environment may have reduced
contaminant levels since the-RI/FS. If complete biological information is collected, comparison to the
Sediment Standards may also result in reduced cleanup areas.
83.5 Monitoring
Physical, chemical and biological monitoring after cleanup will continue as long as necessary.
Monitoring during implementation of remedial actions is important to assess short term environmental
and human health effects and to confirm compliance with the selected remedial design. For FS cost
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estimates, monitoring was assumed to continue for thirty years and generally included chemical and
biological monitoring, seafood sampling, and monitoring of treatment areas as appropriate.
Monitoring costs are included under operation and maintenance (O&M), and vary according to the
different alternatives and cleanup areas.
8.4 Description of the Alternatives
The following descriptions of cleanup alternatives considered for the East Harbor is a summary of
more detailed information provided in the Eagle Harbor FS. Cost estimates for the East Harbor areas
estimated in the FS (Table 10) are provided in Tables 12A and 12B. Table 13 provides estimates of
the time necessary to implement each alternative. Remedial action areas, costs, and time frames for
the East Harbor would be refined during remedial design.
ALTERNATIVE A. NO ACTION/NATURAL RECOVERY
The No Action Alternative must be evaluated to provide a baseline to which other alternatives can be
compared. No active remediation of sediment contamination would take place, although source
control activities at the Wyckoff Facility would continue. Humans and aquatic organisms using con-
taminated areas of Eagle Harbor would continue to be exposed to elevated levels of contaminants until
natural recovery achieved cleanup objectives.
Natural recovery could occur gradually through deposition of new sediments, degradation of PAH by
physical, chemical, and biological processes, and movement of contaminated fine sediments with tidal
and other currents. As stated in Section 8.3.3 above, intertidal areas are expected to recover within
ten years, once significant contaminant sources are controlled, and natural recovery processes may
also significantly reduce contamination in subtidal areas with marginal contaminant levels. Most of
the more heavily contaminated subtidal areas, where natural recovery could take fifty years or more,
have been addressed by the existing cap.
No initial costs are incurred. The cost of monitoring of seafood to evaluate reductions in contaminant
concentrations over time is included as O&M.
ALTERNATIVE B. INSTITUTIONAL CONTROLS/NATURAL RECOVERY
As with the No Action alternative, the Institutional Controls alternative does not involve active
remediation of contaminated sediments. Natural recovery of contaminated sediments would occur
gradually in some areas (see No Action), and institutional controls such as access and use restrictions,
health advisories, and hazard education programs for the public would be used to limit potential
human exposure to contaminants. These measures would be continued as needed until concentrations
of mercury and PAH were below levels of concern for human health.
Use restrictions would include increased posting of the existing health advisories against fish and
shellfish consumption in intertidal and subtidal areas to reduce the potential for human exposure to
unacceptable levels of contaminants in seafood. Fencing would be used to restrict access to beach
areas near the Wyckoff Facility. Restrictions on commercial harvesting of fish and shellfish could
also be implemented. Dredging in problem areas would be restricted, and best management practices
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(BMPs) for maintenance of creosoted pilings and other shoreline operations would be required. Costs
are considered under O&M.
ALTERNATIVE C. CAPPING
Capping consists of leaving the contaminated subtidal and intertidal sediments in place and covering
them with clean material to isolate the contamination. The physical conditions that the cap would be
exposed to would vary depending on its location and would determine the detailed design
requirements.
Subtidal capping would involve placement of a layer of clean medium- to coarse-grained sand
approximately 1-meter (3-feet) thick, to isolate contaminants and limit their vertical migration and
release into the water column. This cap thickness would also limit the potential for marine organisms
to reach the contaminated sediment. For purposes of estimating costs it was assumed that suitable
sandy material could be obtained by dredging within a 3-kilometer (1.9 mile) radius of Eagle Harbor.
Identification of an actual source would be conducted during remedial design and would affect cost.
In order to provide full coverage of cleanup areas at the intended thickness, the side-slopes of the cap
would extend into adjacent unremediated areas. For purposes of estimating quantities in the FS,
approximately 3 meters (10 feet) of overlap was assumed. Cap performance requirements and
limitations on permeability (e.g., construction materials, cap maintenance requirements, and testing of
contained materials) would be further analyzed during remedial design.
Physical conditions such as the slope and wave environment as well as biological and habitat issues
would be considered in the selection of material characteristics and could affect the thickness and
extent of capping. Areas affected by currents induced by ferry propellers could require a coarser
grained material as "armoring" to hold the cap in place.
It is estimated that design, procurement, and construction of the cap (for both subtidal and intertidal
areas) would take three to four years. This assumes six months for final design, a year for pilot
testing of the cap, three months for design refinement, six months for mobilization/demobilization,
and six months for placement of capping materials.
ALTERNATIVE D. REMOVAL, CONSOLIDATION, AND CONFINED AQUATIC
DISPOSAL
Confined aquatic disposal (CAD) consists of dredging or excavating contaminated sediments from the
subtidal and intertidal zones, placing them in an excavated subtidal pit in Eagle Harbor, capping the
relocated sediments with a meter (three feet) of clean sediment from the pit, and disposing of any
excess clean sediment at a Puget Sound Dredge Disposal Analysis (PSDDA) open-water disposal site
(or applying them to beneficial uses elsewhere). Important considerations in the design of this
alternative include:
The CAD site would be in a subtidal area below -7.5 meters (25 feet) mean lower low water
(MLLW), with low current velocities. The upper surface of the CAD cap would be consistent with
the original harbor bottom contours in order to minimize cap erosion, disruption of navigation, and
impacts on harbor circulation. The west-central portion of the harbor could meet these conditions and
has sufficient area to accommodate .the contaminated sediment.
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Contaminated sediment removed from intertidal areas would be replaced with uncontaminated material
of a similar type to mitigate the loss of intertidal substrate. If necessary, some of the contaminated
sediment removed from the subtidal area would be replaced with similar uncontaminated material to
assist in the restoration of eelgrass.
It is estimated that design, procurement, and construction of the CAD for the total volume of con-
taminated sediment would take four to six years. This estimate assumes a minimum of a year for
design, six months to excavate the CAD basin, two years to dredge and place the contaminated
sediment, six months to cover, and a year to mobilize and demobilize the operation.
ALTERNATIVE E. REMOVAL, CONSOLIDATION, AND NEARSHORE DISPOSAL
The alternative consists of constructing a containment area adjacent to the shore in Eagle Harbor,
removing contaminated sediments from subtidal and intertidal problem areas, placing the contaminated
sediments in the containment area in the harbor, and capping the sediments in the containment area
with imported clean sand. The final elevation of the upper surface of the containment area would
match the existing upland surface.
This nearshore fill site would be located in an area that would minimize disruption of navigation and
operations on contiguous upland areas. The size of the disposal site would depend on the ultimate
volume of sediment removed. Contaminated sediment in the disposal site would be kept saturated in
order to limit contaminant release. The surface of the clean sediment cap would be paved if
necessary for post construction use, and a stormwater collection system would be installed. As the
containment area would be built in nearshore areas which generally provide valuable habitat, habitat
mitigation would probably be required. It is estimated that design, procurement, and construction of
tfie nearshore disposal facility for the total volume of sediment would take four to five
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Table 12A. Estimated Costs* of East Harbor Sediment Cleanup Alternatives
Evaluated in Feasibility Study
INTERTIDAL SEDIMENTS
Alternative
No Action/Natural Recovery
Institutional Controls/Natural Recovery
Capping
Confined Aquatic Disposal
Nearshore Confined Disposal .
Incineration
Biological Treatment
Costs in Dollars
Based on FS Intertidal Area"
55,000 m2 (14 acres)
Initial
0
24,000
5,900,000
9,800,000
29,500,000
99,200,000
71,500,000
O&MC
300,000
376,000
600,000
800,000
1,500,000
2,800,000
1,900,000
Total
300,000
400,000
6,500,000
10,600,000
31,000,000
102,000,000
73,400,000
Table 12B. Estimated Costs" of East Harbor Sediment Cleanup Alternatives
Evaluated in Feasibility Study
SUBTIDAL SEDIMENTS
Alternative
No Action/Natural Recovery
Institutional Controls/Natural Recovery
Capping
Confined Aquatic Disposal
Nearshore Confined Disposal
Incineration
Biological Treatment
Costs in Dollar^
Based on FS Lower Bound Aread
of 235,000m2 (58 acres)
Initial
0
0
13,700,000
26,600,000
46,700,000
238,700,000
176,000,000
O&MC
300,000
400,000
800,000
1,300,000
1,000,000
5,200,000
4,000,000
Total
300,000
400,000
14,500,000
27,900,000
48,600,000
243,900,000
180,000,000
' Initial capital costs are based on 1990 dollars, and present worth of O&M was calculated using an 8% discount rate and a 30-year
amortization period. Estimates are intended to be within +50% and -30% of actual costs, based on the estimated volumes.
* Intertidal costs are based on 55,000 square meters, an area which includes 35,000 square meters of inlertidal sediments in the East Harbor
and 20,000 square meters in the West Harbor. Actual costs would be lower, but relative costs would not change significantly.
' O & M is operations and maintenance, including monitoring.
1 Estimated costs are based on areas developed for the Feasibility Study, for lower bound cleanup areas. This estimate is close to the
estimated area of sediments not included in the capped areas of the East Harbor but which fail one or more of the MGUL chemical criteria
(259,000 nf), as shown in Table 10.
* Areas outside the existing cap which fail one or more of the SQS chemical criteria are estimated at 488,000 of, approximately double the
lower bound areas. Estimated costs for addressing these are provided in the FS, as upper bound cost estimates.
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ALTERNATIVE L. REMOVAL, TREATMENT BY BIOLOGICAL SLURRY, DISPOSAL
In this alternative, excavated sediments would be mixed and aerated as a slurry to enhance the
biological degradation of PAH and other organic contaminants. Control over treatment conditions
would help maintain treatment effectiveness with the relatively low organic content of the sediments at
Eagle Harbor.
The sediment would be treated in mobile treatment reactors brought on site. The treatment tanks
would be covered, and the off-gas would be treated as appropriate. The area needed for the treatment
tanks and equipment would be about 30,000 m2. A portion of the Wyckoff Facility could be used for
the treatment operations if they were coordinated with ongoing and future cleanup activities there.
The treated sediments would be tested to demonstrate compliance with performance standards and
disposed of at a PSDDA open-water disposal site. Excess wastewater from the sediment treatment
would be treated on site prior to discharge to the harbor. It is estimated that design, procurement,
and remediation would take nine to eleven years for PAH-contaminated sediments throughout Eagle
Harbor, For the East Harbor only, slightly less time would be necessary.
Table 13. Estimated Time to Implement East Harbor Remedial Alternatives
Alternative
A. No Action
B. Institutional Controls/Natural Recovery
C. Capping
D. Removal, Consolidation, and Confined Aquatic Disposal
E. Removal, Consolidation, and Nearshore Disposal
H. Removal, Treatment by Incineration, and Disposal
L. Removal, Treatment by Biological Slurry, and Disposal
Estimated Time for Design,
Procurement, and
Remediation* (years)
NA
1 to 10
3 to 4
4to6
4 to 5
8 to 11
9 to 11
Modification of FS Table 5-1, which assumed cleanup of all problem areas in Eagle Harbor (430,000 MJ).
Timeframes adjusted to reflect volumes in areas for which alternative was developed for detailed evaluation.
NA = Not Applicable.
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9. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
The NCP requires that each remedial alternative be evaluated according to specific criteria. The
purpose of the evaluation is to identify the advantages and disadvantages of each alternative and
thereby guide selection of the remedy offering the most appropriate means of achieving the stated
cleanup objectives. While all of the nine criteria are important,.they are weighted differently in the
decision-making process. The alternatives described in Section 8 were evaluated under CERCLA
according to the following criteria:
Threshold Criteria
Overall protection of human health and the environment
Compliance with ARARs
Primary Balancing Criteria
Long-term effectiveness and permanence
Reduction of toxicity, mobility, or volume through treatment
Short-term effectiveness
Implementability
Cost-effectiveness
Modifying Criteria
State and tribal acceptance
Community acceptance
Following is a description of the evaluation criteria and the comparative evaluation of each candidate
remedial alternative.
9.1 Threshold Criteria
The remedial alternatives were first evaluated in relation to the threshold criteria of overall protection
of human health and the environment and compliance with ARARs. The threshold criteria must be
met by the candidate alternatives for further consideration as remedies for the ROD.
9.1.1 Overall Protection of Human Health and the Environment
This criterion considers whether, as a whole, each alternative would achieve and maintain protection
of human health and the environment.
All of the cleanup alternatives evaluated are protective of human health except No Action. However,
to ensure protection of human health prior to achievement of cleanup objectives, active cleanup
alternatives should be combined with institutional controls as needed.
All alternatives evaluated are protective of the environment, except for No Action and Institutional
Controls. However, if the site cleanup objective incorporates a ten year recovery period, these
alternatives would also be protective of the environment in areas predicted to achieve this objective in
the specified time frame through natural recovery.
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9.1.2 Compliance with Applicable or Relevant and Appropriate Requirements
The evaluation against this criterion considers whether each alternative would comply with ARARs,
whether a waiver of any ARAR might be necessary and justified, and assesses other information or
guidance "to be considered."
All alternatives except No Action and Institutional Controls could comply with the primary ARAR
(the Sediment Standards) throughout the East Harbor. No Action and Institutional Controls would
comply with the ARAR only if a ten-year natural recovery period were incorporated into the cleanup
objective, and then only in areas predicted to recover within this timeframe. Other potential ARARs
associated with implementation of individual alternatives, such as dredging, filling, storage, treatment,
or disposal, could be met. In some cases, special engineering controls, treatability testing, or habitat
mitigation would be necessary to ensure compliance with these ARARs.
9.2 Primary Balancing Criteria
Once an alternative satisfies the threshold criteria, five primary balancing criteria are used to evaluate
other aspects of the potential remedies. Each alternative is evaluated by each of the balancing
criteria. One alternative will not necessarily receive the highest evaluation for every balancing
criterion. The balancing criteria evaluation is used to refine the selection of candidate alternatives for
a site. The five primary balancing criteria are: long-term effectiveness and permanence; reduction of
toxicity, mobility or volume through treatment; short-term effectiveness; implementability; and cost-
effectiveness. Each criterion is further explained in the following sections.
92.1 Long-Term Effectiveness and Permanence
The evaluation against this criterion assesses the long-term effectiveness of each alternative in
maintaining protection of human health and the environment after the cleanup objectives have been
met, with a focus on the magnitude of risk posed by treatment residuals or untreated contaminated
sediments remaining at a site after the remedial actions have been completed.
CERCLA requires that EPA favor options in which treatment is a principal element over institutional
controls or off-site disposal of untreated waste. In general, treatment is practicable and preferable for
small volumes of highly contaminated material. Containment alternatives are appropriate when large
volumes containing relatively low levels of contamination are involved, as is the case for many
contaminated sediment sites.
The treatment alternatives evaluated for the East Harbor, including Biological Treatment and
Incineration, would permanently destroy PAH and other organic compounds.
Alternatives involving containment, such as Capping, Confined Aquatic Disposal, and Nearshore
Disposal, can be effective over the long term, but they do not permanently remove or destroy the
contaminants. Long-term monitoring and maintenance are necessary to assure their continued
protectiveness.
Alternatives relying on natural recovery, such as No Action and Institutional Controls, would require
monitoring to verify achievement of site objectives. Depending on whether recovery was achieved
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through natural contaminant breakdown or through burial by deposits of clean sediment, the
effectiveness and permanence of natural recovery alternatives could be comparable to treatment
alternatives or containment alternatives.
9.2.2 Reduction of Toxicity, Mobility, or Volume through Treatment
The evaluation against this criterion assesses the anticipated performance of the treatment technologies
in each of the alternatives.
Alternatives involving treatment, including Biological Treatment and Incineration, would reduce the
toxicity and mobility of PAH contamination.
Alternatives involving containment of untreated sediments, such as Capping, Confined Aquatic
Disposal, and Nearshore Disposal, restrict the movement of contaminated sediments and limit the
availability of the contaminant to marine organisms. However, these alternatives do not alter the
toxicity, mobility, or volume of the chemical contaminants themselves.
Alternatives relying on natural recovery, such as No Action and Institutional Controls, could reduce
the toxicity, mobility, and volume of contaminated sediments if recovery was achieved through
natural contaminant breakdown.
9.23 Short-Term Effectiveness
The evaluation against this criterion assesses the effectiveness of each alternative in protecting human
health and the environment from construction and implementation of a remedy until achievement of '
the cleanup objectives. It focuses on protection of the environment, the community, and workers
during implementation of the remedial action.
Alternatives involving treatment, such as Biological Treatment and Incineration, would require
dredging of contaminated sediments, since in situ treatment methods for PAH contamination have not
been developed. Dredging would destroy the existing benthic community and in subtidal areas could
have negative short-term impacts on the environment, particularly in areas with oily free-phase
contamination. Specifically, subtidal dredging could remobilize contamination into the water,
potentially spreading it to nearby areas. For intertidal areas, the short-term environmental risks
associated with dredging are reduced somewhat, because sediments can be excavated at low tide to
minimize remobilization of contaminants. However, changes in habitat as a result of dredging could
require mitigation. In addition to risks associated with dredging, dredged sediments and treatment
residuals could pose risks to the environment, workers, and the community from.potential
contaminant releases during subsequent storage, processing, and treatment phases. Among active
remedial alternatives, implementation of treatment alternatives takes the longest (Table 13).
Alternatives involving consolidation and containment, such as Confined Aquatic Disposal and
Nearshore Disposal, would also require dredging. The short-term risks to the environment due to
dredging would be the same as for treatment alternatives. Creation of a containment facility in
subtidal or nearshore areas would destroy the existing benthic community. The shorter time frame
for implementation of the containment alternatives would pose short-term risks to the community for a
correspondingly shorter time. Intertidal sediments could be excavated at low tide, posing a reduced
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risk of contaminant releases. However, dredging or construction of a containment facility in intertidal
areas could require mitigation for loss of or damage to valuable nearshore habitat.
The in situ alternative of Capping provides the greatest short-term effectiveness. A clean sediment
cap can be implemented relatively quickly and poses fewer short-term risks to human health and the
environment, because contaminated sediments are not dredged, stored, or processed. As with other
active alternatives, placement of a cap would damage or destroy the existing benthic community,
depending on placement methods and cap thickness. Capping in intertidal areas could require habitat
mitigation for loss to or damage of valuable nearshore habitat.
The No Action and Institutional Controls alternatives have the least short-term impacts from
implementation but do not protect the environment unless natural recovery can achieve the cleanup
objectives in a reasonable time frame.
As noted, all active remedial alternatives would damage or destroy the existing benthic community.
However, studies show that marine organisms soon recolonize clean sediment. This process can
begin immediately after capping or removal of contaminated sediments; however, development of a
mature community of sediment-dwellers can take several years. Recolonization of larger areas may
be slower.
9.2.4 Implementability
Three factors were evaluated to assess the implementability of the remedial alternatives: technical
feasibility, administrative feasibility, and the availability of disposal sites, services, and materials.
<.
Technical feasibility requires an evaluation of the ability to construct and operate the technology, the
reliability of the technology, the ease of undertaking additional remedial action (if necessary), and
monitoring considerations. All of the alternatives evaluated are technically feasible, although testing
would be necessary to assure the achievement of performance standards for treatment alternatives.
Active alternatives would involve monitoring and engineering controls to limit releases during
implementation and, with the exception of Capping, would require management of dredging and/or
treatment residuals.
Administrative feasibility assesses the ability to coordinate actions with other agencies. All of the
alternatives evaluated are administratively feasible. Active remedial alternatives require coordination
with ferry traffic. Alternatives involving treatment, such as Biological Treatment and Incineration,
involve extensive and complex administrative and regulatory requirements. In particular, Incineration
is less administratively feasible because of the difficulties in locating an incinerator on site in a
residential community. Alternatives involving containment, such as Confined Aquatic Disposal,
Nearshore Disposal, and Capping, include dredging and clean sediment placement, which could
require coordination with PSDDA agencies.
The availability of disposal sites, services, and materials requires evaluation of the following factors:
availability of treatment, storage capacity, and disposal services; availability of necessary equipment
and specialists; and availability of prospective technologies. Alternatives involving removal and
dewatering of sediment prior to treatment, containment, or disposal require the management of
sediment and drained water. Treatment options would necessitate storage or sequential dredging, to
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accommodate the materials to be treated, and management of treatment residuals. Upland areas for
on-site storage, processing, and treatment are limited, to the upland Wyckoff Facility. Until
completion of remedial studies at the facility, designation of such an area would be premature.
9.2.5 Cost-Effectiveness
In evaluating project cost-effectiveness, present-worth estimates of capital costs and operation and
maintenance costs are developed for each alternative and compared. Estimates are aimed at providing
an accuracy of +50 to -30 percent within the defined'scope.
Alternatives involving treatment, such as Biological Treatment and Incineration, generally entail
higher initial costs. On-site containment alternatives, such as Confined Aquatic Disposal, Nearshore
Disposal, and Capping, tend to have lower costs initially but have higher monitoring and/or
maintenance costs over the long term. Institutional controls are usually low cost, and No Action is
the least costly, but both of these alternatives may not achieve the cleanup objectives or meet
threshold evaluation criteria. As shown in Tables 12A and 12B, the overall costs for active remedial
alternatives are highest for Incineration and lowest for Capping.
9.3 Modifying Criteria
The final two criteria reflect the apparent preferences among, or concerns about, the alternatives, as
expressed by the State, the Suquamish Tribe, and the Community.
93.1 State and Tribal Acceptance
The State of Washington Department of Ecology supported the preferred alternative for the East
Harbor in both the 1991 and 1994 Proposed Plans. Although Ecology has also written to support the
technical aspects of the East Harbor selected remedy, formal concurrence is still under consideration
and will not be provided prior to issuance of this ROD.
The Suquamish Tribe reviewed key documents such as the RI and FS and received technical
memoranda issued by EPA and the Proposed Plan. Contamination of fish and shellfish resources in
Eagle Harbor is of concern to the Tribe and may be addressed by cleanup actions described in the
selected remedy.
93.2 Community Acceptance
EPA considered all comments submitted during the public comment period on the 1991 Proposed Plan
as well as the 1994 plan for final cleanup in the East Harbor. The comments have been taken into
account during the selection of the remedy for the East Harbor operable unit.
The 1991 Proposed Plan identified capping of heavily contaminated sediments as EPA's preferred
alternative for an interim action pending further control of contaminant sources at Wyckoff.
Comments on this plan indicated that the community was divided; while many supported EPA's
preferred alternative, others indicated a preference for lower cost alternatives such as No Action
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(natural recovery over an indefinite period) or some combination of institutional controls, sediment
source removal, and natural recovery.
The 1994 Proposed Plan identified capping as the preferred alternative for remaining contaminated
areas and identified a framework for implementing other actions as necessary until further control of
sources warranted implementation of the final remedy. Limited comment was received, but none
indicated opposition to EPA's preferred alternative. EPA responsiveness summaries for both
Proposed Plans are included in Appendix B.
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10. SELECTED REMEDY
Based on CERCLA, the NCP, the comparative analysis of alternatives, and the Administrative
Record, EPA has selected the following alternatives for cleanup of East Harbor sediments:
Institutional Controls/Natural Recovery (Alternative B) for intertidal areas, and
Institutional Controls (Alternative B) combined with Capping (Alternative C) in
subtidal areas of the East Harbor, excluding subtidal sediment recovery zones to be
designated for specific environmental or technical reasons.
As described in Section 3.5, subtidal capping in an area of the East Harbor heavily contaminated with
PAHs was completed under CERCLA removal authorities. Figure 13 shows the approximate capped
area, subtidal areas, and intertidal areas addressed by the selected remedy. The selected remedy
incorporates the existing cap as an element of the final cleanup of the East Harbor.
EPA's selected remedy includes a phasing approach for implementing certain necessary actions in the
East Harbor while ongoing cleanup actions at the Wyckoff Facility provide increased control of
contaminant sources to Eagle Harbor sediments. This approach is shown graphically in Figure 14.
Once significant sources have been sufficiently controlled, the final cleanup of remaining
contaminated areas in the East Harbor will commence. The selected remedy also provides for
modifications as necessary to ensure that the cleanup objectives will be achieved.
EPA has determined that for the East Harbor the selected remedy provides the best balance of the
nine evaluation criteria. Relative to institutional controls alone, the selected remedy protects both
human health and the marine environment. Relative to other active alternatives, the selected remedy
minimizes short term effects associated with dredging and is quickly and readily implemented at a
lower cost, once contaminant sources have been controlled. Long-term effectiveness can be ensured
by monitoring and maintenance. State of Washington Department of Ecology concurrence on the
selected remedy is under consideration.
Discussion of the East Harbor selected remedy follows, under the following main headings:
Cleanup Objectives
Problem Areas and Actions
Implementation
Estimated Costs
CERCLA Five-Year Review
The selected remedy must achieve the project objectives described in Section 10.1, below.
10.1 Cleanup Objectives
For the East Harbor, an overall sediment cleanup objective, developed according to the Sediment
Standards, is combined with a supplemental objective for intertidal areas, developed by EPA. The
combined sediment cleanup objectives were developed to ensure protection of human health and the
environment.
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This section provides:
A summary of the framework provided by the Sediment Standards for selection of sediment
cleanup objectives,
A description of the specific objectives selected for intertidal and subtidal areas of the East
Harbor, and
A brief rationale for their selection.
Sediment cleanup goals and objectives for the East Harbor are largely the same as those for the West
Harbor; however, the subtidal cleanup objective has been modified to reflect specific conditions in the
East Harbor. Cleanup in the East Harbor and West Harbor is intended to ensure that within a
reasonable time frame, sediment contamination is within the range of "minor biological effects" or
below, and at levels protective of human health.
10.1.1 Sediment Standards
The Sediment Standards, the primary ARAR for the East Harbor, were promulgated in April 1991
and provide a framework for developing sediment cleanup objectives at Eagle Harbor. The long-term
goal of the Sediment Standards is "to reduce and ultimately eliminate adverse effects on biological
resources and significant health threats to humans from surface sediment contamination." The process
for defining sediment cleanup areas (referred to in the Sediment Standards as "sites") and establishing
cleanup objectives for these areas is summarized in the following paragraphs.
The Sediment Standards define two levels of chemical criteria. The most stringent level corresponds
to the long-term goal of "no adverse effects" on sediment biological resources, while the less stringent
level corresponds to "minor adverse effects" on these resources. The chemical criteria are based on
Puget Sound data which indicate sediment chemical concentrations above which specific biological
effects have always been observed in test sediments (see Section 6 for description of AETs). The
Sediment Standards also define two levels of biological criteria based on several types of biological
tests. Like the chemical criteria, the biological criteria correspond to no adverse effects and minor
adverse effects levels.
The absence of adverse effects is predicted by attainment of the more stringent chemical criteria, the
"marine sediment quality standards" (SQS) chemical criteria while minor adverse effects are predicted
by chemical concentrations ranging from the SQS to the less stringent "minimum cleanup level"
(MCUL) chemical criteria. At contaminant levels above the MCUL, more significant effects are
predicted, and sediment cleanup must be considered.
Cleanup areas may be defined using chemical criteria alone; however, the Sediment Standards
recognize that the chemical data may not accurately predict biological effects for all sediment
locations. Biological testing, allowed under the Sediment Standards, can be conducted to determine
whether biological effects predicted by the chemical concentrations are actually occurring. The three
measures must include two tests for acute toxicity to marine organisms and one for chronic biological
effects. If all three biological criteria are met for a given area, this area is not included in the
cleanup area and does not require cleanup under the Sediment Standards. Failure to meet the
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U)
I
Figure 13
EAST HARBOR ROD AREAS
-------
NPE69206.02.04 ROD Areas 8/16/94 CJS
FERRY
TERMINAL
West i
Harbor
East Harbor
150
rf-
Scale In Meters
LEGEND
300 Meters
Steep Areas
>7»7*?» Eelgrass
l<" '' Subtidal Log Rafting Area
H^H Intertidal Seep Areas
Areas indicated are approximate
WYCKOFF
FACILITY
Figure 13A
OTHER SPECIFIC AREAS IDENTIFIED
IN SELECTED REMEDY
-------
JL I
Framework for Cleanup Actions in the East Harbor
WYCKOFF FACILITJY
Facility
Source
Control
Actions!
1987.91
Study, of 0eart«i>
Construction
" -',, of Cleanup
Increasing Source Control
Sediment Cleanup Actions:
(schedule will depend upon achievement of source control goals)
EAST HARBOR
Sufficient
Facility
Source
Control*
Harbor
Cleanup
Alternatives
Placement
of Existing
Sediment
Cap
Final
Sediment
Cleanup
Decision
I
1
WEST HARBOR
Refine Cleanup Area
Design Cleanup
Define Baseline for
Natural Recovery
Implement
Subtidal Cap
-
Monitoring,
O&M (10 yrs)
Monitor Intertidal Natural
Recovery (10 yrs)
Determination made on the basis of yearly evaluations of harbor and facility data
Other Necessary Actions:
Monitoring Dock Demolition
Institutional Armoring
Controls
Ptool '.
Sediment
Cleanup
Decision
* Refthfe Cleanup Area"
« D«s|gn^Clwnup £
« Deftrte BR&Ilne totj';; :.
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;; 'X ? ;, Monliorlhg/0 & Mt; (10 Yeirtt*)
Pre-1992
1992
1993 1994 I 1995 ' 1996 ' - 1997 ' 1998
Approximate Timeframe
1999
2000
2001
2002
-------
biological criteria at the SQS or MCUL level can be demonstrated by a single biological measure.
Failure of more than one criterion at the SQS level is considered equivalent to failure at the MCUL
level.
The intent of the Sediment Standards is for sediments within a cleanup area to ultimately meet the
sediment quality standards (SQS), the level of no adverse effects. Once a cleanup area has been
defined as described above, a cleanup objective for the area is developed. The objective must be
within the minor adverse effects range defined by the no adverse effects level (the SQS) and the
minor adverse effects level (the MCUL). In all cases, if both biological and chemical data are
obtained, the biological information determines compliance with the cleanup objective developed
under the Sediment Standards.
In certain cases, natural processes such as chemical breakdown, dispersion, or sedimentation may
reduce levels of sediment contamination over time. The Sediment Standards allow selection of an
objective which incorporates a reasonable period of time for natural sediment recovery. A period of
ten years is generally used as the natural recovery period, although extensions beyond the ten year
period may be obtained if warranted. If mathematical modeling predicts that certain areas of
contaminated sediment will meet the cleanup objectives within the natural recovery time frame
without active remediation, natural recovery may be included among alternatives evaluated for these
areas. If natural recovery is selected, the "sediment recovery areas" are delineated, and monitoring
and compliance testing required to confirm the predicted recovery.
Net environmental benefits, cost, and technical feasibility of cleanup must be considered in selecting a
cleanup objective, including one which may incorporate a recovery period. At a minimum, all
sediments in a defined cleanup area must meet the MCUL within ten years after any active
remediation is completed in the area.
10.1.2 East Harbor Cleanup Goals and Objectives
Within the framework described above, cleanup goals and objectives were developed for intertidal and
subtidal sediments in the East Harbor.
Consistent with the intent of the Sediment Standards and the West Harbor ROD, achievement of the
SQS and reduction of contaminants in fish and shellfish to levels protective of human health and the
environment are long-term goals of sediment remedial action in the East Harbor. These goals
represent a conceptual target condition for all Eagle Harbor sediments.
The primary measurable objective for East Harbor sediments, however, is the MCUL (WAC 173-
204-570). As in the West Harbor, the main focus of remedial action in the East Harbor is
achievement of the MCUL, below which minor biological effects are predicted. Compliance with the
MCUL is documented by compliance with the corresponding biological criteria or, in the absence of
biological data, with the chemical criteria of Table III (WAC 173-204-520). Final cleanup in the East
and West Harbor operable units is intended to result in contaminant concentrations at or below the
MCUL in surface sediments throughout Eagle Harbor. MCUL and SQS chemical criteria for PAHs
and mercury are listed in Table 8, and corresponding biological criteria are provided in Table 9.
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EPA developed a supplemental objective for intertidal areas. This intertidal cleanup objective and the
MCUL for subtidal and intertidal sediments are described in the following paragraphs.
Subtidal Sediment Objective
As noted, the subtidal cleanup objectives in the two Eagle Harbor operable units differ in one respect.
While subtidal sediments in both the East Harbor and West Harbor must be included as part of a
cleanup area if they contain contaminant concentrations above the MCUL, in the West Harbor a
natural recovery period is incorporated in the objective for a large subtidal area. Active remediation
is not required for West Harbor sediments in this area if they are predicted to achieve the MCUL
within ten years. For the West Harbor, however, the cleanup objective for subtidal sediments does
not incorporate a recovery period, unless warranted by specific physical and ecological conditions in
certain areas. Except in limited sediment recovery areas, all East Harbor subtidal sediments with
contaminant concentrations above the MCUL require active remediation. The difference between the
East and West Harbor subtidal objectives is further discussed in Section 10.1.4.
Identification of subtidal sediment recovery zones in the East Harbor is provided for only in areas
where capping could adversely affect sensitive and valuable habitat, such as eelgrass, or where
engineered cleanup is not practicable, such as areas which are too steep or too deep. Preliminary
areas with steep slopes or eelgrass beds are identified in Figure 13A. Criteria for delineation of these
areas will be developed during the remedial design phase, based on current environmental science and
engineering information. In remaining subtidal areas, active remediation is required if the top ten
centimeters of sediment contain contaminant concentrations above the MCUL at the completion of
source control. This subtidal objective is termed MCUL-0 in this ROD (because cleanup is required
for areas with contaminant concentrations exceeding the MCUL at 'time zero," control of significant
sources).
Intertidal Sediment Objectives
For East Harbor intertidal sediments, as with intertidal PAH areas in the West Harbor, .the surface ten
centimeters must achieve the MCUL within ten years from control of significant sources to these
areas. Since this objective incorporates the ten-year recovery period, it is termed MCUL-10.
The objective of the MCUL is supplemented by an objective of 1,200 /ig/kg (dry weight), developed
by EPA to address human health risks from consumption of contaminated shellfish in intertidal areas
(See Sections 6 and 7). This objective requires that intertidal sediment HPAH concentrations must
not exceed 1,200 ftg/kg (dry weight). HPAHs most closely approximate the carcinogenic PAHs
evaluated in the risk assessment. The HPAH objective in sediments corresponds to the 90th
percentile of Puget Sound subtidal background HPAH concentrations available at the time of the
RI/FS. Clam tissue concentrations from the RI showed a moderate correlation with intertidal
sediment concentrations, and carcinogenic PAH concentrations in clams from intertidal sediments with
contamination above the HPAH criterion resulted in cancer risk estimates above EPA levels of
concern.
Achievement of the HPAH objective in intertidal sediments is expected to result in corresponding
reductions in clam tissue contamination. This additional objective does not alter the requirement of
achieving the MCUL throughout the East Harbor. Because institutional controls can be used to limit
human exposure in intertidal areas until the cleanup objectives are achieved, however, ten years are
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allowed for sediments to meet the MCUL and the HPAH objectives. This ten year period begins
once significant contaminant sources to intertidal sediments from the Wyckoff Facility have been
controlled.
Intertidal sediments are an important marine habitat, and unlike subtidal sediments are very sensitive
to changes in elevation. Because environmental conditions (such as wave energy, grain size, food
supply, predation, and moisture) vary with minor changes in elevation in the intertidal zone, specific
organisms are adapted to the habitat conditions at different elevations. Changes in elevation caused
by dredging or capping hi the intertidal zone would affect intertidal habitat. Conditions for natural
recovery are significantly better for intertidal than subtidal sediments (See Section 8.3.3). Although
some intertidal areas adjacent to the Wyckoff Facility are clearly more affected by ongoing sources of
contamination than subtidal areas, natural recovery once sources are controlled is expected to
eliminate the need for high-impact cleanup action. For this reason, the intertidal cleanup objective
incorporates the ten-year recovery period.
10.1.3 Rationale for Selected Cleanup Objective for East Harbor
Cleanup action is not required in areas with contamination below the MCUL chemical criteria, either
in the East or West Harbor. Selection of the MCUL as an objective and as a means of defining
cleanup areas is supported for the following reasons:
Uncertainty about predicted biological effects,
Predicted contaminant reduction in areas of marginal contamination, and
The costs and impacts of cleanup.
In the East Harbor, biological effects above the range of "minor adverse effects" were documented in
contaminated sediments between the former wood treating facility and the central channel (See Figure
12). Prior to placement of the existing cap in these areas, sediment contaminant concentrations were
above the MCUL by a significant margin for numerous PAHs. Available biological data for areas
where contaminant concentrations exceeded the MCUL by a narrow margin or for only a limited
number of PAHs did not show biological effects above the MCUL level. Since the predicted
biological effects in such areas were not observed hi two of the three measures, it is probable that
sediments with chemical concentrations below the MCUL have minor or no biological effects.
More importantly, East Harbor areas where minor biological effects would be predicted (i.e. areas
with contamination above the SQS .and below the MCUL) are likely to recover without active
cleanup. Over time, certain organic contaminants, including PAHs, break down in the marine
environment as a result of chemical and biological processes. In addition, biological activity in the
top layer can cause dilution of contaminants by clean sediment mixed hi from above or below the
contaminated zone. As there are no rivers or other major sources of clean sediment to Eagle Harbor,
little new sediment settles in the East Harbor. However, the predominant contaminants are organic,
rather than metals. Sediments with PAH concentrations below the MCUL tend to be at the margins
of the contaminated areas and more distant from the primary contaminant source, the Wyckoff
Facility. In these marginal areas, sediment contamination was likely caused by the transport of
contaminated sediments from other more contaminated areas and is expected to be higher in surface
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sediments than deeper sediments. In addition, cleanup in adjacent MCUL-0 areas is likely to
introduce clean sediments to areas already below the MCUL. Such conditions are good for natural
recovery processes, as described in Section 8.2.3. EPA expects that East Harbor areas with
contamination levels between the SQS and MCUL will continue to improve following implementation
of the remedy.
Given uncertainties about biological effects, as well as the greater potential for contaminant reduction
through natural processes in East Harbor areas where contaminants are below MCUL criteria, EPA
believes the potential benefits of cleanup in these areas do not warrant the costs and short-term
environmental impacts of active cleanup. The MCUL represents an appropriate and achievable
objective for the East Harbor and is consistent with cleanup levels required in the West Harbor.
Achievement of the MCUL will be an important step toward the SQS and considers the factors of net
environmental benefit, cost, and implementability as contemplated by the Sediment Standards.
10.1.4 Comparison with West Harbor
As previously stated, the selection of the MCUL-0 for East Harbor subtidal sediments reflects
different circumstances relative to the West Harbor. Specifically, the decision not to incorporate a
natural recovery period for the East Harbor subtidal sediments is based on:
the extended timeline prior to final East Harbor cleanup and
the level of documented biological effects,
The ROD for final cleanup of the West Harbor was issued in 1992. In addition to requiring
achievement within ten years of remedial action or source control, the West Harbor ROD identified
three supplemental objectives related to removal of a sediment hot spot, capping of areas predicted to
have more significant effects, and institutional controls combined with natural recovery in certain
intertidal areas. Areas where contaminant concentrations are below these objectives but above the
MCUL could be eliminated from active cleanup requirements if EPA approved modeling indicated
that natural recovery would achieve the MCUL in ten years (MCUL-10). If identified, sediment
recovery zones will be in areas where contamination is above the MCUL by a small margin and
where RI data provided no evidence of either minor or significant biological effects. While RI data
were not sufficient to eliminate areas from cleanup, they were supported by other biological studies of
the West Harbor. Cleanup design for the West Harbor is in progress, and implementation of cleanup
actions is anticipated in the next two or three years.
By contrast, for East Harbor sediments additional time is necessary to further control contaminant
sources from the Wyckoff Facility. The East Harbor ROD establishes a phased approach to final
cleanup for this reason (See Figure 14). EPA estimates that sources may be sufficiently controlled
three to six years after issuance of this ROD. Although the existing cap is an important step toward
addressing areas with significant biological effects, final sediment remedial action in the East Harbor
may begin several years after the West Harbor cleanup. RI biological data for the East Harbor show
a range of effects, unlike the West Harbor, where available data showed significant or no effects.
Minor or significant adverse effects may be ongoing, particularly in remaining heavily contaminated
areas close to the Wyckoff Facility. Sediments in such areas tend to contain numerous PAHs at
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concentrations well above the MCUL, rather than a limited number marginally above the MCUL.
Effects in these areas will continue in the years preceding final remedial action. During these years,
contaminant source reduction, natural recovery processes, and the existing cap may contribute to
contaminant reductions in the East Harbor. However, once sources are controlled, further extending
the timeline for recovery in areas predicted to have significant biological effects (above the MCUL) is
not warranted, except in limited sediment recovery zones with sensitive habitat or technical
impracticability. At the time of remedial design, areas may be eliminated from active cleanup if it
can be demonstrated that the predicted effects are not occurring, despite concentrations above the
MCUL chemical criteria.
10.2 Problem Areas and Actions
This section describes specific remedial actions selected to achieve MCUL-0 in subtidal sediments and
both MCUL-10 and HPAH-10 in intertidal sediments.
As stated previously, the selected remedy is as follows:
Capping (with limited sediment recovery zones) in Subtidal Cleanup Areas
Natural Recovery in Intertidal Cleanup Areas
Institutional Controls in Both Areas
Intertidal and subtidal sediment cleanup actions and the institutional controls associated with each are
discussed under separate headings below.
10.2.1 Subtidal Areas
The following paragraphs describe the selected remedy and how it applies to the existing cap,
remaining cleanup areas, and sediments with contaminant levels below the MCUL. Specific actions
are identified which may be implemented to ensure the success of the overall remedy.
Selected Remedy
The selected remedy for subtidal sediments which exceed the MCUL chemical criteria is capping
(Alternative C). As noted, subsequent to the 1991 Eagle Harbor Proposed Plan, a sediment cap over
heavily contaminated areas of the East Harbor was completed under CERCLA removal authorities to
address documented adverse biological effects hi heavily contaminated areas. After significant
sources of contamination have been sufficiently controlled, remaining subtidal sediments with
contamination above the MCUL chemical criteria will also be capped. The areas to be capped will be
based on final remedial design sampling. Biological testing in accordance with the Sediment
Standards may be conducted during remedial design to refine cleanup areas. Areas which meet the
MCUL biological criteria for all such tests do not require cleanup.
As described in Section 8, the assumed cap design is a layer of clean sediments approximately three
feet thick. Contaminant concentrations in capping material must be at or below the Sediment
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Standards SQS chemical criteria. Cap materials must provide suitable habitat for recolonization by
benthic organisms. Placement of capping materials will be designed to minimize impacts on existing
biota and habitat while depositing three feet of clean sediment in all areas where contaminant
concentrations exceed the MCUL in the top ten centimeters.
It may be appropriate to design the cap with less than the three-foot thickness in some areas. Such a
modification would be considered to minimize the effects of sediment placement on the existing
marine environment, provided the long-term effectiveness of the remedy is assured. Other design
modifications may include the placement of coarse materials or other adjustments necessary to ensure
the long-term effectiveness of the cap given the physical, ecological, and chemical conditions in and
near the cleanup area. Such modifications would require prior EPA approval.
Existing Cap
While source control efforts continue, the existing cap will be monitored and any necessary work to
maintain the cap completed. A portion of the cap is located in the ferry navigation path, and areas
closest to the ferry terminal are subject to currents generated by docked ferries. If monitoring
indicates significant erosion of cap materials due to ferry propeller wash or currents, it may be
necessary to supplement the cap with additional sandy materials or to place coarser materials in some
areas to limit cap erosion. These cap maintenance activities will be completed as necessary, either
prior to or in coordination with design and implementation of final actions in other areas.
MCUL Areas
Once control of significant sources has been achieved, cleanup areas will be delineated for design of a
cap to address remaining subtidal cleanup areas. Design of the cap will factor in the existing cap and'
will take into account specific conditions that may call for modifications of the three-foot cap
approach, specifically habitat value, slope, depth, and currents. In certain areas, capping may be
technically impracticable (for example, on steep slopes) or cause impacts to valuable and sensitive
habitat (for example, eelgrass). For such areas, it may be appropriate to allow natural recovery
rather than requiring active remediation. Designation of natural recovery zones in these areas will be
considered only if reasonable engineering modifications to the remedy cannot effectively address these
areas. Further discussion is provided below.
In areas of the East Harbor not addressed by the existing cap, a number of environmental conditions
may dictate modifications to the cap (Alternative C) described in Section 8. The existing cap was
completed in conditions well suited to capping. The cap was placed in gently sloping areas of the
harbor 30 to 50 feet below mean lower low water level (MLLW), except for a small area of shallow
sediments. Eelgrass beds rarely occur below 30 feet, and in the shallow area were extremely sparse.
North of the Wyckoff Facility, a subtidal shoal extends into the East Harbor. Sediments in this area
and at the mouth of Eagle Harbor are subject to stronger currents than protected areas inside the
harbor. In addition, beyond the gradually sloping intertidal area on the east side of the shoal, the
harbor bottom slopes steeply and deepens to over 60 feet below MLLW. If these areas are
contaminated above the MCUL at the time of remedial design, cap design efforts will evaluate
technical modifications to achieve the cleanup objective. If cleanup is technically impracticable, these
areas will be allowed to recover through natural processes and monitoring will be required to verify
natural recovery.
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Immediately adjacent to the Wyckoff Facility is a shallow subtidal area known as the log-rafting area.
In addition to log-rafting, the area was used for loading creosote from barges to the Wyckoff Facility.
Contamination in the sediments was likely caused by a combination of spills, surface runoff,
migration from heavily contaminated facility soils, and other means. EPA has excavated and
removed heavily contaminated soils adjacent to the log-rafting area, but existing sediment
contamination remains severe. Near-surface pockets of free-phase oily contamination have been
observed, and the sediments are very fine. Remediation in this area may require engineering
modifications to minimize impacts of cap placement and to ensure the effectiveness of the cap.
Modifications for effectiveness could include extra cap thickness, special capping materials, or limited
excavation of sediment hotspots for consolidation with Wyckoff Facility soils.
In Puget Sound, eelgrass beds may exist in intertidal and shallow subtidal areas. Eelgrass beds
provide valuable habitat for marine organisms and are difficult to restore once damaged or destroyed.
In the East Harbor, eelgrass beds exist near the harbor mouth on both the north and south shores. If
eelgrass beds are included or directly adjacent to areas contaminated above the MCUL, design efforts
will evaluate ways to minimize impacts to this habitat. If necessary, such areas will be allowed to
recover through natural processes, and monitoring will be required to verify the recovery.
Areas Failing the SOS
Areas of the East Harbor may exceed the long-term goal of the Sediment Standards SQS chemical
criteria at remedial design. Although contaminant concentrations in these sediments already meet the
MCUL and are predicted to continue to improve through ongoing natural recovery processes, limited
monitoring will be conducted in these areas to evaluate ongoing natural recovery processes, the
effectiveness of source control actions at the facility, and changes due to remedial actions in adjacent
areas.
Engineering feasibility in implementing a three-foot cap in adjacent areas with contaminant
concentrations above the MCUL may dictate placement of clean sediment for side slopes in adjacent
SQS areas. Extending the benefits of remediation into SQS areas in this manner would hasten the
achievement of the SQS in the East Harbor, consistent with the intent of the Sediment Standards.
10.2.2 Intertidal Areas
The following paragraphs describe the selected remedy for intertidal sediments, including actions that
may be considered to ensure the success of the overall remedy.
Selected Remedy
The selected remedy for intertidal sediments with total HP AH concentrations of 1,200 /ig/k§ or more
(dry weight) or with PAH concentrations above the MCUL is natural recovery combined with
institutional controls (Alternative B). Contaminant concentrations in such areas must meet the HPAH
objective and the MCUL within ten years from control of significant sources of contamination to
these areas. Monitoring will be necessary to document natural recovery to both these objectives
(HPAH-10 and MCUL-10).
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Based on existing data, intertidal areas of Eagle Harbor where contaminant concentrations exceed the
HPAH objective of 1,200 /ig/kg correspond closely with areas where intertidal sediments exceed two
or more MCUL chemical criteria for individual PAHs. Intertidal sediments adjacent to the inactive
Wyckoff Facility currently exceed both the MCUL and the HPAH objective. Some East Harbor
locations along the north shore may marginally exceed MCUL chemical criteria for a single PAH.
As noted previously, PAHs are rapidly degraded by exposure to ultraviolet or visible light (Payne and
Phillips, 1985), while microbial degradation of PAHs is enhanced by aerobic conditions. For this
reason, sediment natural recovery is most effective in intertidal areas, where sediments are exposed to
air and sunlight between high tides.
Once control of significant sources to the beach adjacent to the Wyckoff Facility is achieved, beach
sediments are expected to meet both the HPAH-10 and the MCUL-10 within ten years. At the start
of the ten-year recovery period, the problem areas will be delineated and baseline conditions
established for monitoring natural recovery. Monitoring will be necessary during the natural recovery
period to document progress toward and achievement of the objectives. In locations on the north
shore natural recovery is expected to achieve the MCUL chemical criteria readily.
Because the HPAH objective is intended to protect human health, biological testing according to the
Sediment Standards cannot be used to eliminate or reduce cleanup requirements for sediments
contaminated above this level. In intertidal areas which exceed the MCUL but are less than or equal
to the HPAH objective, biological testing may be conducted to demonstrate the absence of significant
biological effects. In such areas, if the MCUL biological criteria are met, no further consideration is
required. Comparisons to the MCUL chemical criteria will take into account the potential for low
total organic carbon content to affect results, in accordance with guidance developed for the Sediment
Standards.
Prior to initiation of the ten-year recovery period, efforts to further control contaminant sources at the
Wyckoff Facility will continue. During this time, monitoring of the adjacent intertidal areas will be
necessary. The purpose of monitoring in such areas is to evaluate the potential for natural recovery
in heavily contaminated areas and to assess the need for additional actions. Such actions may be
necessary to ensure the success of the overall remedy. Specifically, for more heavily contaminated
intertidal areas where monitoring indicates that natural recovery processes are insufficient to achieve
the two objectives, possible additional actions include:
Enhancement of natural recovery processes, and
Excavation of sediment hotspots.
Due to years of oily seepage, subsurface reservoirs of contamination may exist in the intertidal zone
adjacent to the Wyckoff Facility. Such sources could re-introduce contamination to surface sediments
through tidal flushing, offsetting reductions in surface sediment contamination through natural
recovery processes.
Subsequent to the ROD, additional sampling will be conducted to identify such reservoirs and areas
where natural recovery may be inhibited. Mechanisms for enhancing or accelerating biological or
photochemical breakdown processes may be sufficient to address such areas. Nutrient enhancement
and tilling of the sediments are two examples of such mechanisms. Test plots or pilot tests to ensure
that a specific mechanism is appropriate for site conditions may be necessary. Enhancement of
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natural recovery would be implemented as necessary if tests indicate that enhancement of natural
recovery is likely to accelerate hotspot contaminant reduction sufficiently. This mechanism could be
extended into other contaminated intertidal areas, a decision which would be based primarily on cost-
effectiveness and design considerations.
If the sampling identifies areas that will not achieve the objectives despite enhancement mechanisms,
excavation of specific hotspots will be considered as a further modification of the remedy. Excavated
sediments could be managed with upland soils in coordination with Wyckoff Facility cleanup actions.
The monitoring, tests, and potential additional actions will be implemented as appropriate in
coordination with activities at the Wyckoff Facility and with sediment remedial design, to ensure that
the sediments will achieve the objectives within the ten-year recovery period.
10.2.3 Institutional Controls/Site Use Restrictions
Institutional controls are part of the selected remedy. In combination with remedial action, they will
ensure protect human health and the environment in both subtidal and intertidal areas.
Health Advisory
Consumption of clams, crabs, fish and other marine organisms from Eagle Harbor is considered a
pathway of potentially significant health concern. In addition to implementation of specific
institutional controls in intertidal areas, the selected remedy supports continuation of the existing
health advisory described in Section 2.2, calls for efforts to increase public awareness of seafood
contamination, and requires periodic monitoring of seafood contaminant levels.
Since 1985, the Bremerton-Kitsap County Health District has alerted citizens to chemical and bacterial
concerns, advising against the harvest of fish or shellfish from the harbor, through signs posted in
publicly accessible areas, a hotline, and correspondence to potentially affected residents. EPA
supports the continuation of this advisory until chemical contaminants in seafood are below EPA
levels of concern identified below. Although not part of this ROD, it is expected that the advisory
will continue as necessary for other reasons, such as bacterial contamination.
Indicator concentrations for contaminants of concern were identified in the West Harbor ROD to
evaluate potential continuing human health risks and to generally assess the success of remedial
action. The same levels will be used to evaluate East Harbor data. The concentrations correspond to
levels protective of human health for cancer and non-cancer effects. The indicator concentrations for
methyl-mercury in fish and shellfish tissue are 0.22 mg/kg and 0.98 mg/kg (wet weight), respectively.
The sum of carcinogenic PAH concentrations is IS /ig/kg and 60 jig/kg in fish and shellfish tissue,
respectively. In coordination with the requirement of the West Harbor ROD and regional monitoring
programs, periodic testing for chemical contaminants in fish, crabs, and clams from Eagle Harbor
will be used to assess public health risks and evaluate the success of remediation in reducing
contaminant concentrations in edible seafood. While the indicator thresholds are among the primary
considerations for continuance of the health advisory, EPA and the health agencies may establish
additional thresholds for other contaminants to protect human health.
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At the CERCLA five-year review and ten years after completion of remedial action in the West
Harbor, EPA will evaluate the need for continued monitoring of fish and shellfish tissues. If tissue
monitoring does not indicate a trend toward decreasing concentrations of site contaminants ten years
after completion of all final remedial actions in Eagle Harbor, EPA will evaluate the need for
additional action.
Use/Access Restrictions
Some restrictions on use and access of the East Harbor may be necessary to ensure protection of
human health prior to and during implementation of the selected remedy, and to ensure protection of
completed remedial actions.
It is currently possible to approach the beach adjacent to Wyckoff by boat as well as by walking north
from Rockaway Beach. Warning signs are posted on the fence surrounding the upland Wyckoff
Facility to advise against the harvesting of seafood from the adjacent beach areas. To further
minimize access to these areas, additional warning signs (using the same visual symbols and the
warning in multiple languages) will be posted and maintained, and physical barriers (a fence or other
barrier) will be positioned at the south end of property. To the extent possible, warning signs and
physical barriers will be effective at low tides, when an extensive area is exposed. To make the
warnings visible to recreational boaters, larger signs will also be posted.
In addition, restrictions on uses of remediated subtidal and recovering intertidal areas may be
necessary to prevent impacts on ongoing or completed cleanup. For example, restrictions on
anchoring or dredging in or near capped areas will be imposed if necessary.
103 Implementation
Figure 14 provides a framework for the timing of remedial activities. Detailed plans and schedules
for key elements of remedial design and remedial action will be developed as appropriate information
becomes available. Final sediment cleanup actions will be initiated after control of significant
contaminant sources at the Wyckoff Facility. If sources to a specific area are controlled in advance of
other, source control, cleanup action in these areas may proceed separately, depending on the costs of
separate design and implementation relative to the benefits of early cleanup. While source control
efforts continue, certain actions may be necessary to ensure the protection of human health and the
environment.
Implementation of the selected remedy requires coordination among EPA, Ecology, and other
involved agencies, including the Washington State Ferries, the City of Bainbridge Island, the COE,
federal and state natural resource agencies, the Suquamish Tribe, and state and local health agencies.
Coordination with the affected community and potentially responsible parties will also be important
during remedial design and remedial action. Coordination with West Harbor cleanup activities and
with source control and site cleanup work at the Wyckoff Facility will be necessary. Although no
critical habitats have been identified in the East Harbor, EPA will continue to coordinate with the
U.S. Fish and Wildlife Service to assure that remedial activities do not adversely affect threatened or
endangered species. EPA will issue fact sheets and hold public meetings at key points in the
implementation process, to keep the community involved and informed. Periodic meetings with
interested community groups can be arranged if requested.
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Key elements of implementation include the following:
coordination with contaminant source control efforts,
monitoring prior to final remedial design,
potential necessary actions prior to final cleanup,
final remedial design and remedial action, and
post-remedial action monitoring and maintenance.
These elements are described in the following sections.
10 J.I Coordination with Contaminant Source Control
Efforts to control Wyckoff Facility sources of contamination to the East Harbor are being managed as
part of Superfund cleanup activities at the Wyckoff Facility and Groundwater operable units. The
East Harbor ROD does not require specific source control actions at these operable units, but the East
Harbor selected remedy will be implemented in coordination with activities at these operable units.
Current source control efforts at the Wyckoff Facility include the operation of a groundwater
extraction system since 1990 and removal of sludges stored in tanks and buried at the facility. While
these actions have reduced seepage of oily contamination on the beaches adjacent to the facility, the
seepage has not been eliminated. Dissolved contamination in groundwater beyond reach of the
extraction system may also be a source of low-level contaminant inputs to portions of the East
Harbor. The existing sediment cap was completed in areas of the East Harbor where significant
sources were sufficiently controlled to warrant cap placement in areas of documented biological
impacts and heavy contamination.
An interim decision for the Wyckoff groundwater operable unit has been proposed (July 25, 1994)
which would allow enhancement of the extraction system and other groundwater source control
measures. In addition, final soil and groundwater remedies will be selected and implemented after
completion of the remedial study at the Facility, and additional early actions may be identified in the
coming years to enhance source control.
These actions are expected to control significant sources of contamination to nearshore and intertidal
areas as well as subtidal contaminated areas of the East Harbor. Final sediment cleanup in the East
Harbor will not commence until significant sources are sufficiently controlled. A report will be
prepared annually as part of the East Harbor selected remedy. The report will summarize available
source data, identify additional data needs, and assess the status of source control. The annual reports
will be available for public review and will integrate information from the following, at a minimum:
monitoring of dissolved and non-aqueous phase liquids in the extraction wells and
groundwater treatment unit,
systematic observations of visible seeps on adjacent beaches and nearshore subtidal areas,
findings developed as a result of the Wyckoff Facility remedial investigation, ongoing early
actions, or remedial design of interim or final facility actions,
environmental monitoring of intertidal and subtidal sediments in the East Harbor.
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This information will be generated in connection with the Wyckoff Facility operable units, except for
the last element, which will be completed as part of the monitoring described in Section 10.3.2
below.
As source control efforts become increasingly effective, plans for final remedial design sampling will
be developed and sources of sediment capping material will be sought. A determination of sufficient
source control will be made by EPA, after issuance of a fact sheet and consultation as appropriate
with natural resource and health agencies, the community, and other interested parties.
Implementation of the pre-design sampling plans and design of final sediment remedial action will
follow EPA's determination of sufficient source control.
10.3.2 Monitoring Prior to Source Control
Although sampling will be necessary after source control to support design of the final remedial
action, limited environmental monitoring will also be conducted prior to source control to meet the
following objectives, as necessary:
to assess the conditions of the existing cap, including maintenance needs,
to support evaluations of the status of source control,
to identify potential contaminant hotspots in remaining cleanup areas,
to evaluate changes in the extent of contamination due to natural recovery and placement of
the existing cap,
to refine expectations regarding implementability of the remedy in specific areas,
to refine methods for enhancing intertidal natural recovery, and
to assess eel grass beds potentially affected by completed or future cleanup.
The monitoring may include physical, biological, and chemical analyses, as well as visual
observations. Such monitoring would be completed under EPA approved plans and to the extent
possible would be integrated to minimize costs and to ensure consistency. Monitoring results will be
linked to decisions or actions in the East Harbor, such as maintenance of the existing cap,
determinations of source control, decisions to implement specific elements of the selected remedy, and
plans for focused design sampling.
IOJ.3 Potential Necessary Actions Prior to Final Remedial Action
In addition to sediment remedial actions, other actions may be necessary to ensure protection of
human health and the environment. These actions are part of the selected remedy, and as appropriate
will be designed and implemented in coordination with other remedial activities. The actions may
occur prior to or concurrent with final sediment remediation.
Maintenance of the Existing Cap
The existing sediment cap in the East Harbor covers over fifty acres of heavily contaminated
sediments, at cap thicknesses ranging from one to three feet. Plans to monitor the cap are in
preparation and will be implemented as part of the remedial design phase immediately following the
ROD through final remedial action. Monitoring will be used to verify that the cap is continuing to
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provide clean habitat and isolating underlying contaminated sediments, as well as to determine the
need for additional actions to maintain the cap.
Sampling will focus on surface sediments in the capped area and on the cap's physical integrity.
Limited use of coring or other methods which penetrate the cap may be necessary to assess the
effectiveness of the cap in isolating sediment contaminants. Impacts of potential continuing sources to
the cap, recolonization of the cap by benthic organisms, and effects of the cap on surrounding areas,
including eelgrass habitat, will also be evaluated.
If significant erosion of cap material is observed in areas which require isolation of contaminated
sediments, the selected remedy provides for resupplying cap materials, potentially in combination with
placement of cap with gravel or coarser materials to protect the cap from erosion. Additionally, areas
of the cap where monitoring indicates a need for thicker coverage to ensure protection of the
environment may be supplemented. As with the existing cap, any additional work on the cap will
require coordination with the Washington State Ferries and affected resource agencies, regarding
scheduling, necessary navigation depths, and other logistical matters.
In-Water Structures near Wvckoff Facility
In intertidal and shallow subtidal areas near the Wyckoff Facility, numerous ill-water structures used
to support the former wood-treating operations remain. Structures include a large dock (known as the
West Dock), numerous dolphins, pilings remaining from a dock to the East (known as the Milwaukee
Dock), and various floating structures. The dock structures may interfere with or significantly
increase the cost of active sediment remediation and may come to pose a safety hazard as they
deteriorate.
Removal of these in-water structures will be required if necessary to ensure the protection of human
health and the environment. The design decision regarding whether and when to remove in-water
structures will consider the potential for the structures to be useful for future remedial work or other
site uses at the Wyckoff Facility, the potential for the structures to release wood treating chemicals as
they deteriorate or during demolition, and the potential for re-use of the structural materials.
103.4 Final Sediment Remedial Design and Remedial Action
Once EPA has made the determination to proceed with remedial design and remedial action for final
sediment cleanup, environmental sampling and engineering work will be necessary to support the
design. This will include the following work, as needed:
chemical and/or biological testing to delineate areas exceeding the cleanup objectives,
evaluations of existing eelgrass beds to avoid or minimize impacts from cleanup,
engineering evaluations for work in sloped areas, areas subject to potential cap erosion, and
other design issues,
sampling to define baseline contaminant concentrations in natural recovery areas, and
identification of volumes, characteristics, and sources of appropriate capping material.
To locate a source of available clean material suitable for capping, coordination with agencies
responsible for evaluating regional dredging projects will be necessary.
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Design and implementation of final sediment cleanup may take two to three years. During
construction, monitoring will be conducted to evaluate short-term effects on the environment, to
document construction as planned, and to ensure protection of human health and the environment.
10.3.5 Post-Remedial Action Monitoring and Maintenance
During sediment recovery and after final remediation, long-term monitoring is necessary to document
progress toward, attainment of, and continued compliance with the cleanup goals and objectives
described in Section 10.1. Plans for monitoring to be conducted while source control efforts continue
will be supplemented to develop the long-term monitoring approach for the East Harbor once final
cleanup areas have been defined.
In addition to sediment chemistry and biological tests to document attainment of the cleanup
objectives, the plans may include sampling for other environmental conditions, such as physical
conditions, concentrations of contaminants in marine organisms of importance to human health or the
environment, evaluations of the diversity and abundance of marine organisms, and integrative
measures of exposure to, or effects from, sediment contamination.
EPA will review and approve the plans in consultation with Ecology, the Suquamish Tribe, and the
appropriate public health and natural resource agencies. Where possible, sampling and other activities
will be conducted according to existing protocols (e.g., PSEP); will complement other Puget Sound
monitoring efforts, such as the Puget Sound Ambient Monitoring Program, (PSAMP); and will
provide information for evaluating as many objectives as possible.
As new information arises regarding sources, contaminants, or biological effects, sampling
requirements may be modified by EPA. New or modified monitoring methods may be developed
over this period. EPA will continue to evaluate these developments and, in consultation with
Ecology, the Suquamish Tribe, natural resource agencies, and other technical resources, will adopt
them as appropriate.
Monitoring efforts will be tiered and will focus primarily on the first ten years after completion of
remedial action. If monitoring after remedial action documents compliance with the MCUL by or
before the tenth year, the type and frequency of monitoring may be adjusted, or monitoring may be
phased out, provided continued compliance with the objectives is assured. Monitoring requirement!
may be re-evaluated at the CERCLA Five-Year Review, described in Section 10.5.
If monitoring indicates that the MCUL may not be attained within ten years, EPA will evaluate the
need for additional remedial action during the CERCLA five-year review (Section 10.5, below) or as
appropriate.
10.4 Estimated Costs
Estimated costs associated with the selected remedy are summarized in Table 14,. including the
following:
estimates from the FS for sediment capping, natural recovery, and institutional controls, and
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Table 14
Estimated Costs1 of East Harbor Selected Remedy
Gn U.S. Dollars)
Cleanup Action
Intertidal Natural
Recovery/Institutional Controls2
Annual Monitoring Prior to Final
Remedial Design
Maintenance of Existing Cap3
Removal of In-Water Structures4
Subtidal Cap
Design/Implementation
Total for monitoring and final
sediment cleanup
Total including other necessary
actions
Low-End Cost
$400,000
$300,000
$500,000
$1,500,000
$2,000,0003
$2,700,000
$ 4,700,000
High-End Cost
$800,000
$600,000
$1,000,000
$3,000,000
$14,500,000
$15,900,000
$19,900,000
i
1 Refer to assumptions in Section 10.4 and following footnotes.
1 High-end cost for institutional controls based on combined FS
estimates for subtidal and intertidal institutional controls.
Since this may duplicate some elements, actual costs should be lower.
3 Shaded costs are for potential other necessary actions, which
may or may not be implemented.
4 High-end costs based on disposal of debris as hazardous waste.
This is unlikely to be required.
5 This estimate is derived from actual costs for the existing cap, .which was placed over an area
approximately equivalent area to the remaining MCUL area. The existing cap cost under $2,000,000.
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a range of estimated costs for potential other necessary actions, including monitoring,
maintenance of the existing cap, and demolition of in-water structures.
During remedial design, the FS sediment cleanup volume estimates will be refined. Costs are
anticipated to change accordingly. In addition, the ranges for other necessary actions will be refined
prior to design and implementation of these actions.
The present worth cost estimates for capping, natural recovery, and institutional controls are intended
to be within +50% and -30% of the actual costs of remediation, based on volume estimates
established during the FS using the following key assumptions. Brief discussion of uncertainties
associated with the assumptions follow in italics:
Areas contaminated above MCUL chemical criteria in RI data will, if tested, fail the Sediment
Standards MCUL biological criteria and require a cap as described in Section 8. Based on
existing data, it is likely that complete biological testing will identify some areas failing the
MCUL chemical criteria with only minor effects. This would reduce areas requiring active
cleanup. Design modifications for steep, deep, or erosional areas may also change the costs.
Natural recovery has not occurred in areas where contaminant concentrations exceeded the
MCUL in RI sampling. Costs may decrease if source reduction and natural recovery
processes ongoing since initial data collection (1988) have reduced the area where
contaminant concentrations exceed the MCUL.
Costs for capping material are as estimated in the FS. As demonstrated with the existing cap,
coordination of capping with planned dredging of clean sediments can significantly reduce
material costs.
Costs for East Harbor intertidal areas are two thirds of estimated FS costs for all Eagle
Harbor intertidal HPAH areas (including West Harbor areas). While consistent with the East
Harbor areas relative to overall areas, design and mobilization costs due to separating the
East, and West Harbor could increase the cost.
Estimated cost ranges for other necessary actions also relied on assumptions, which may change as
additional information is developed. Key assumptions include the following, with an explanation of
the basis for each:
Any armoring necessary to protect the cap will be in an area between 8 and 11 acres in areas
affected by ferry wash. Visual monitoring of the cap during and after construction indicated
varying degrees of erosion in such areas. Actual areas needing armoring are unlikely to be
significantly smaller or larger than this range.
Monitoring prior to source control will average $100,000 per year and may continue for three
to six years. This estimate is based on scoping of periodic monitoring for the existing cap and
other limited monitoring averaged over a ten-year period. More extensive monitoring to
identify hotspots or evaluate design modifications could increase costs. Planned actions at the
facility are unlikely to result in sufficient source control in less than three years. If more than
six years is necessary, monitoring may be scaled back to minimize costs.
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Hotspot excavation will not be necessary in log-rafting and intertidal areas. EPA does not
anticipate that these actions will be necessary. Therefore, assumptions about volumes are not
provided. While costs for excavation in the log-rafting area and intertidal areas can be
estimated using relevant items in the FS estimate for nearshore disposal of intertidal HP AH
sediments, costs for management of excavated materials could change significantly due to
coordination with cleanup of Wyckoff Facility soils.
Based on these assumptions, total costs for the selected remedy are expected to range from $6 to $20
million. Costs associated with source control activities at the Wyckoff Facility are not included in
cost estimates for the East Harbor.
10.5 CERCLA Five-Year Review
The FS discussed the Five-Year Review mandated by CERCLA for remedial actions that leave
contaminants at the site. For this selected remedy, the review is required at least once every five
years to ensure that human health and the environment are being protected.
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11. STATUTORY DETERMINATIONS
Under CERCLA, EPA's primary responsibility is to undertake remedial actions that assure adequate
protection of human health, welfare, and the environment. In addition, Section 121 of CERCLA
establishes cleanup standards which require that the selected remedial action comply with all
applicable or relevant and appropriate requirements (ARARs) established under federal and state
environmental law, unless any such requirements are waived by EPA in accordance with established
criteria. The selected remedy must also be cost-effective and must utilize permanent solutions,
alternative treatment technologies, or resource recovery technologies to the maximum extent
practicable. Finally, CERCLA regulations include a preference for remedies that employ treatment
that permanently and significantly reduces the volume, toxicity, or mobility of hazardous waste as a
principal element. The following sections discuss how the selected remedy meets these CERCLA
requirements.
11.1 Protection of Human Health and the Environment
The selected remedy is protective of human health and the environment. Among the alternatives
which are protective of human health and the environment, the selected remedy provides the best
balance of long-term effectiveness and permanence; reduction of toxicity, mobility, volume, and
persistence; short-term effectiveness; implementability; and cost. The selected remedy considers state
and community acceptance.
The selected remedy combines capping of contaminated subtidal sediments (with limited sediment
recovery zones), natural recovery in intertidal areas, and institutional controls. Capping subtidal
sediments with clean materials is an effective means of quickly protecting the environment with
minimal short-term effects. Within subtidal areas with contaminant concentrations above the MCUL,
the existing cap or additional capping after control of Wyckoff contaminant sources will limit potential
redistribution of PAHs, provide clean habitat, and reduce environmental exposures up the food chain.
In intertidal areas with contaminant concentrations above intertidal cleanup objectives and in subtidal
areas with contaminant concentrations below the MCUL, natural recovery will continue to reduce
surface sediment chemical concentrations without the unnecessary physical .disturbance and costs of
active remediation. Similarly, in subtidal sediment recovery zones designated for reasons of habitat
value or technical feasibility, the costs and impacts of active remediation will be minimized.
Institutional controls consisting of restrictions to beach access and additional warnings regarding the
harvest and consumption of contaminated seafood will further ensure protection of public health,
while restrictions on anchoring, dredging, or other sediment disturbance will protect capped areas.
11.2 Compliance with Applicable or Relevant and Appropriate Requirements
The selected remedy will be designed and implemented to attain all ARARs identified in this section.
Applicable requirements are those clean-up standards and other substantive environmental
requirements, criteria, or limitations promulgated under federal or state law which specifically address
a hazardous substance, pollutant, or contaminant, remedial action, location, or other circumstance at a
CERCLA site. Relevant and Appropriate requirements are those cleanup standards and other
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substantive environmental requirements, criteria, or limitations promulgated under federal or state law
which are not applicable, but nevertheless address matters sufficiently similar to those encountered at
a CERCLA site (relevant), and their use is well suited to a particular site (appropriate).
ARAR compliance for on-site remedial action is strictly limited to the substantive portions of ARARs.
Administrative or procedural requirements in ARARs, such as approval or consultation with
administrative bodies, permitting requirements, reporting, record keeping, and enforcement provisions
need not be met. Off-site actions, however, comply with both administrative and substantive aspects
of federal and state law.
The ARARs for the East Harbor selected remedy are as follows:
By taking remedial action for sediments with contaminant concentrations above the minimum
cleanup level (MCUL), EPA will comply with the substantive requirements of the primary
ARAR, the State of Washington Sediment Management Standards (Washington
Administrative Code [WAC] Chapter 173-204). Subtidal sediments are required to meet the
MCUL immediately after completion of the remedy, and intertidal sediments are required to
meet the MCUL ten years after source control, unless otherwise indicated in the selected
remedy.
Fill activities (e.g., capping in subtidal or intertidal areas) and dredging or excavation of
contaminated sediments (for any excavated intertidal PAH hotspots) will comply with the
substantive requirements of federal regulations promulgated pursuant to Sections 401 and
404(b)(l) of the Clean Water Act (40 C.F.R. § 230) and Section 10 of the Rivers and
Harbors Act (33 C.F.R. § 320-330). These regulations are intended to protect marine
environments and to prevent unacceptable adverse effects on municipal water supplies,
shellfish beds, fisheries (including spawning and breeding areas), wildlife, and recreational
areas during dredging activities.
Fill, dredging, and other remedial activities conducted within 200 feet of the shoreline will
comply with the promulgated substantive requirements of the Kitsap County Shoreline
Master Plan (WAC 173-19-2604), as developed pursuant to the State Shoreline
Management Act (RCW 90.58), and adopted by the former City of Winslow.
If fill or dredging activities will change the natural flow or bed of state waters, EPA will meei
the substantive requirements of the Washington State Hydraulic Code Rules (WAC 220-
110). These substantive requirements are intended to protect fish by, e.g., placing limitations
on the timing and duration of dredge/fill activities.
If modifications to the natural recovery alternative is necessary in the intertidal PAH areas,
liquids and other wastewaters from any sediment dewatering related to excavation of
sediments will be managed (treated and discharged) in compliance with substantive
requirements of the following:
State of Washington Water Pollution Control Act (RCW 90.48) and Water
Quality Standards (WAC 173-201);
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National Pollution Discharge Elimination System (NPDES) Permit Program
(WAC 173-220) for effluent limitations, water quality standards, and other substantive
requirements; and
State Waste Discharge Permit Program (WAC 173-216) restrictions on certain
discharges to POTWs (if wastewater is discharged to a POTW).
Most RCRA hazardous waste is regulated under a program delegated to the Washington
Department of Ecology. If sediments are excavated and taken off site, State Dangerous
Waste Regulations (WAC 173-303) promulgated pursuant to this authority will be met.
These regulations control most RCRA listed hazardous/dangerous waste (listed DW/HW) and
TCLP characteristic waste (characteristic DW/HW), and include criteria for "Washington-
State-only" dangerous waste (DW) and "extremely hazardous waste" (EHW). RCRA
hazardous waste requirements not included in the delegated State program will also be
complied with. Excavated sediments managed with the upland Wyckoff Facility soils will
comply with any Dangerous Waste Regulations and RCRA ARARs identified in the Wyckoff
Facility ROD.
Off-site disposal must also comply with the Amendment to the NCP, Procedures for
Planning and Implementing Offsite Response Actions [aka the Off-Site Rule (40 CFR
300.440).
Additional policies, guidance, and other laws and regulations to be considered for remedial actions
include:
Executive Orders 11990 and 11988 (40 CFR 6, Appendix A) which are intended to avoid
adverse effects, minimize potential harm, and restore and preserve natural and beneficial uses /
of wetlands and floodplains;
Requirements and guidelines for evaluating dredged material, disposal site management,
disposal site monitoring, and data management established by Puget Sound Dredge Disposal
Analysis (PSDDA) (1988, 1989);
' Critical toxicity values (acceptable daily intake levels, carcinogenic potency factor) and U.S.
Food and Drug Administration action levels for concentrations of mercury and
polychlorinated biphenyls (PCBs) in edible seafood tissue;
EPA Wetlands Action Plan (U.S. EPA 1989) describing the National Wetland Policy and
primary goal of "no net loss";
Element S-4 of Puget Sound Water Quality Management Plan (relating to confined disposal
of contaminated sediments) ((1988, 1989, 1991));
Puget Sound Stormwater Management Program (pursuant to 40 CFR Parts 122-24, and
RCW 90.48);
AKART (All Known, Available, and Reasonable Technologies) guidelines and 1989 PSWQA
plan. Elements P-6 and P-7 for the development of AKART guidelines and effluent limits for
toxicants and particulates.
Federal Ambient Water Quality Criteria (40 CFR 131)
Puget Sound Estuary Program Protocols, (1987) as amended, for sample collection,
laboratory analysis, and QA/QC procedures.
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11J Cost Effectiveness
EPA believes that the combination of remedial actions identified as the selected remedy for the East
Harbor will reduce or eliminate the risks to human health and the environment at an expected cost
between $6 and $20 million dollars. The remedy is cost-effective. It provides an overall
protectiveness proportional to its costs.
By phasing the remedy to allow necessary actions to proceed while efforts to further control sources
of contamination continue, and by using lower-cost containment alternatives for the large areas of
moderate to marginal contamination, the selected remedy cost-effectively provides an appropriate level
of protection.
Specific modifications of the selected remedy, coordinated with soil cleanup at the Wyckoff Facility
are a cost-effective approach to ensuring that sediment cleanup will meet cleanup objectives within ten
years from source control. Allowing natural recovery in limited subtidal areas and in intertidal areas
where cleanup objectives will be achieved in ten years, and allowing biological testing to eliminate
cleanup requirements for areas meeting Sediment Standards biological criteria avoids costly and
unnecessary remedial actions.
11.4 Utilization of Permanent Solutions and Alternative Treatment Technologies
The selected remedy utilizes permanent solutions and alternative treatment technologies to the
maximum extent practicable. However, because treatment of the principal threats at the site was not
found to be practicable, this remedy does not satisfy the preference for treatment as a principal
element.
A number of alternative technologies were explored in the FS, particularly for PAH-contaminated
sediments. In situ treatment alternatives for subtidal sediments are not practicable, however.
Treatment alternatives necessarily involve dredging of contaminated sediments.
Although toxic to marine organisms, sediment contamination in the East Harbor is present at
relatively low levels except in areas of free-phase oily contamination. For high volumes of material
containing relatively low levels of contamination, containment is an appropriate remedy. For smaller
volumes of subtidal sediment containing free-phase oily contamination, treatment could be an
appropriate remedy, but dredging was judged to pose a significant short term risk to the environment
due to potential releases of oily contamination and contaminated fine particles. Treatment or disposal
of dredged sediments at an upland facility would involve complex implementability issues, high costs,
and extended time frames for effective treatment. For these reasons, treatment was not judged
practicable for East Harbor sediments. Subtidal areas containing free-phase contamination were
successfully capped under CERCLA removal authorities.
For intertidal sediments, excavation at low tide could minimize the releases necessary for ex situ
treatment, but since the volumes are relatively low (Table 10) and the potential for recovery without
active remediation is high, natural recovery is the primary focus of the intertidal selected remedy. If
portions of the intertidal area are determined not to have the potential for natural recovery, excavation
may be required. Depending on the upland soil remedy selected at the completion of the Remedial
Investigation and Feasibility Study for the Wyckoff Facility, treatment may be used for these soils.
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Management of excavated intertidal sediments with upland soils could reduce unit costs for intertidal
sediment volumes alone, due to economies of scale.
11.5 Preference for Treatment as a Principal Element
The East Harbor selected remedy for sediments does not satisfy the CERCLA preference for
treatment. Treatment was not judged practicable for East Harbor sediments. The principal threat in
the East Harbor is defined as subtidal sediments containing free-phase oily contamination. As stated
above, treatment of these heavily contaminated sediments would have required dredging. Releases
from dredging could pose significant short-term environmental risks. Treatment or disposal of
dredged sediments at an upland facility would involve complex implementability issues, high costs,
and extended time frames for effective treatment. Subtidal areas containing free-phase contamination
were successfully capped under CERCLA removal authorities.
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12. DOCUMENTATION OF SIGNIFICANT CHANGES
EPA reviewed public comments on the 1994 Proposed Plan. In response, EPA has made the changes
to the Proposed Plan and has incorporated them into the selected remedy. These changes are
discussed below:
1. Postponement of the decision to demolish in-water structures at Wyckoff.
Concerns raised by the community included the high costs of demolition and the potential value of
existing structures for future uses at the Wyckoff Facility. If necessary to protect human health and
the environment, EPA will require demolition of the structures. However, the decision will be
finalized based on developing plans for future uses of the site, the .condition of the structures, and
their effect on sediments and cleanup plans in the East Harbor, as described in Section 10.3.4.
2. Addition of detail regarding source control determinations.
The community requested additional details regarding EPA's determination of sufficient control of
significant sources. Although additional information may need to be incorporated depending on
developments at the Wyckoff Facility, EPA has added a list of elements to be considered for assessing
source control, as described in Section 10.3.2.
3. Addition of sediment recovery zones as an element of the selected remedy in subtidal areas.
The Proposed Plan identified eelgrass beds and steeply sloped areas as implementation issues
potentially requiring modifications of a subtidal cap. The ROD formally provides for die designation
of sediment recovery zones for such areas if engineering modifications cannot reasonably address
them. Sediment recovery zones are factored into the subtidal cleanup objectives (Section 10.1.2) and
are described as an element of the subtidal selected remedy (Section 10.2.1). Evaluation and
identification of sediment recovery zones would occur during remedial design.
4. Clarification of tune frames for achievement of sediment cleanup objectives in subtidal and
intertidal zones and for implementation of potential additional actions to ensure protection of
the overall remedy.
The selected remedy provides more detail than the Proposed Plan on the cleanup objectives in
intertidal and subtidal areas of the East Harbor, and explains why different time frames are selected in
each area for achievement of the cleanup objectives. It also clarifies the timing of additional actions
which may be necessary to ensure the success of the overall remedy.
The above changes are logical outgrowths from information in the RI/FS and the 1994 Proposed Plan.
The selected remedy, which incorporates these changes, provides a framework for major East Harbor
decisions. Additional refinement of the selected remedy is anticipated during remedial design, based
on physical, biological and chemical data and information developed regarding control of contaminant
sources. Minor, significant, and fundamental changes to the remedy after issuance of the ROD will
be evaluated and made in accordance with the NCP.
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References*
CH2M Hill. Data Report. Remedial Investigation. Eagle Harbor Site. Kitsap County. Washington.
Prepared for U.S. Environmental Protection Agency. 1989.
CH2M Hill. Eagle Harbor Remedial Investigation Report for Eagle Harbor Site. Kitsap County.
Washington. Prepared for U.S. Environmental Protection Agency. November 1989.
CH2M Hill. Technical Memoranda. Numbers 1-13. (Complete listing on Table 1 of ROD).
Prepared for U.S. Environmental Protection Agency. 1989 - 1991.
CH2M Hill. Revised Risk Assessment. Eagle Harbor Operable Unit. Wyckoff/Eagle Harbor Site.
Kitsap County. Washington. Prepared for U.S. Environmental Protection Agency. May 1991.
CH2MHill. Public Comment Feasibility Study. Eagle Harbor Operable Unit. Wvckoff/Eagle Harbor
Site. Kitsap County. Washington. Prepared for U.S. Environmental Protection Agency. November
1991.
CH2M Hill. Memorandum to Ellen Hale (EPA") Regarding PAH Indicator Concentration Update.
May 18, 1992.
CH2M Hill. Data Summary Report. Wyckoff OU RI/FS Offshore Investigation. Prepared for U.S.
Environmental Protection Agency. March 1994.
Foentes, R. Memorandum to Ellen Hale (EPA) Regarding Eagle Harbor Mercury Ho^ Spot.
November 1, 1991.
Malins, D.C., et al. Summary Report on Chemical and Biological Data from Eagle Harbor. National
Marine Fisheries Service, Seattle, Washington. 1984bk.
Malins, D.C., et al. Toxic chemicals in sediments and biota from a creosote-polluted harbor:
relationships with hepatic neoplasms and other hepatic lesions in English sole (Parophrvs vetulus).
Carcinogenesis. 6:1463-1469. 1985.
Payne, J.R., and C.R. Phillips, Photochemistry of petroleum in water. Environmental Science and
Technology 19:569-579, 1985.
Puget Sound Water Quality Authority. 1989 Puget Sound Water Quality Management Plan (and
updates). Seattle, Washington. October 1988.
PTI Environmental Services. Performance Standards for Puget Sound Reference Areas. Draft Report.
Prepared for Washington Department of Ecology. Olympia, Washington. 1989.
PTI Environmental Services. Briefing Report to the EPA Science Advisory Board: The Apparent
Effects Threshold Approach. Prepared for U.S. Environmental Protection Agency, Region 10.
1988c.
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PTI Environmental Services. Confined Disposal of Contaminated Sediments: Development
Documentation. Final. January 1990.
Simenstad et al. Estuarine Habitat Assessment Protocol. Prepared for U.S. Environmental Protection
Agency, Region 10, Office of Puget Sound. September 1991.
State of Washington Department of Fisheries. Salmon. Marine Fish, and Shellfish Resources and
Associated Fisheries in Washington's Coastal and Inland Marine Waters. Technical Report Number
79, Revised. April 1992.
Tetra Tech. Preliminary Investigation. Eagle Harbor. Bainbridge Island. Washington. Prepared for
Black and Veatch, Engineers-Architects under contract with the Washington State Department of
Ecology. Bellevue, Washington. 1986:
Tetra Tech. Health Risk Assessment of Chemical Contaminants in Puget Sound Seafood. Prepared
for the U.S. Environmental Protection Agency Region 10, Office of Puget Sound, Seattle, WA.
Tetra Tech, Inc. Bellevue, Washington. 1988.
Tetra Tech. Puget Sound Estuary Program: Recommended Protocols for Sampling and Analyzing
Subtidal Benthic Macroinvertebrate Assemblages in Puget Sound (and other PSEP protocols and
updates). Prepared for U.S. Environmental Protection Agency, Region 10. Seattle, Washington.
1986.
U.S. Army Corps of Engineers, Seattle District. Thin Layer Placement of Dredged Material. Eagle
Harbor. Washington. Feasibility Analysis. March 1992.
U.S. Army Corps of Engineers, Seattle District. On-Scene Coordinator's Report: Statement of
Findings - East Harbor Operable Unit Removal Action. Wyckoff/Eagle Harbor Superfund Site.
September 1994.
U.S. Environmental Protection Agency. An Exposure and Risk Assessment for Benzofalpyrene and
other Polycvclic Aromatic Hydrocarbons. Office of Water Regulations and Standards, Washington
D.C. 1982.
U.S. Environmental Protection Agency. Health Effects Assessment for Polycvclic Aromatic
Hydrocarbons flPAHs). Office of Research and Development; Office of Health and Environmental
Assessment; Environmental Criteria and Assessment Office. Cincinnati, Ohio. 1984.
U.S. Environmental Protection Agency. Risk Assessment Guidance for Superfund: Human Health
Evaluation Manual. Part A. Interim Final. OSWER Directive #9285-701A. July 1989c.
U.S. Environmental Protection Agency. Statement of Work. Remedial Investigation/Feasibility Study
Risk Assessment. Region 10. January 1990.
U.S. Environmental Protection Agency. Obtaining a Soil and Debris Treatabilitv Variance for
Remedial Actions (OSWER Directive # 9347.3-06FS). Office of Emergency and Remedial Response.
September 1990.
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U.S. Environmental Protection Agency. The Proposed Plan for Cleanup of Eagle Harbor. Region 10,
December 16, 1991.
U.S. Environmental Protection Agency. West Harbor Operable Unit. Wvckoff/Eagle Harbor
Superfiind Site. Record of Decision. Region 10, September 1992.
U.S. Environmental Protection Agency. Request for a $2 Million Exemption and Approval of a
Removal Action for the East Harbor Operable Unit of the Wyckoff/Eagle Harbor Superfund Site.
Region 10, June 15, 1993.
U.S. Environmental Protection Agency. The Proposed Plan for Final Cleanup of the East Harbor.
Region 10, June 8, 1994.
U.S. Environmental Protection Agency. The Proposed Plan for Interim Action. Wvckoff/Eagle
Harbor Superfund Site. Wyckoff Groundwater Operable Unit. Region 10, July 25, 1994.
* This is a partial list of documents used in preparing the Record of Decision. The decision is based
on the Administrative Record for the site.
b References from RI/FS documents retain the suffix letter used in the original citation for
consistency.
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APPENDIX A
-------
Region 10
1200 Sixth Avenue
Seattle WA 98101
Alaska
Idaho
Oregon
Washington
June 8,1994
The Proposed Plan for Final Cleanup of the
East Harbor
Wyckoff/Eagle Harbor
Bainbridge Island, Washington
Public Comment Period:
June 8 through July 8, 1994
Meeting for Public Comment:
June 22, 1994, 7-9 PM
at
The Judd Huney Room
402 Bjune Drive SW
Bainbridge Island, WA
INTRODUCTION
This proposed plan describes sediment
cleanup alternatives evaluated for the Bast
Harbor portion of the Wyckoff/ Eagle Harbor
Superfund Site on Bainbridge Island,
Washington (Figure 1) and identifies the
alternative preferred by the U.S.
Environmental Protection Agency (EPA).
The preferred alternative combines several
alternatives presented in this proposed plan
to cost-effectively protect human health and
the environment. EPA is presenting this
information for public comment in
compliance with federal Superfund law.
This proposed plan describes cleanup
alternatives for the East Harbor only. The
East Harbor includes marine sediments
north and east of the Wyckoff facility and is
one of four "operable units" at the Wyckoff/
Eagle Harbor site, described in Table 1. EPA
is the lead agency for the Wyckoff/Eagle
Harbor site and works closely with other
state and federal natural resource
management agencies, health agencies, and
tribes. The Washington Department of
Ecology (Ecology) supports EPA's preferred
cleanup alternative for the East Harbor.
Last winter, a sediment cap was placed over
an area of heavily contaminated sediments
in the East Harbor (Figure 2). Other
sediment contamination, however, remains.
The purpose of this proposed plan is to
address these areas of remaining
contamination in a phased cleanup and to
ensure the long term effectiveness of the
existing cap. Under EPA's preferred
alternative, described in detail on page 16,
the existing cap would be monitored and
maintained, and additional capping would
be completed in remaining contaminated
areas. Beach sediments are predicted to
recover naturally and would be monitored to
document contaminant reduction. Harvest
of shellfish from contaminated beaches
adjacent to the Wyckoff Facility would be
discouraged by a fence and warning signs to
supplement the existing health advisory.
Sediment cleanup actions would not begin
until contaminant sources at the Wyckoff
wood-treating facility are further controlled.
EPA's proposed phasing approach is further
discussed on page 10. Ongoing cleanup at
-------
the Wyckoff facility has reduced oily seepage
onto the beach and will continue to reduce
these sources. Over the next several years,
EPA will continue to pump oil and
contaminated groundwater to minimize the
seepage while evaluating comprehensive
cleanup alternatives for the Wyckoff facility.
Under the proposed action, EPA would
review the results of facility and sediment
monitoring each year, until it is clear that
sediment cleanup can proceed without risk
of recontamination. New data would then
be collected to determine final cleanup areas
for cap design. Until that time, necessary
work in the East Harbor would continue,
such as monitoring and maintaining the
existing cap, fencing of contaminated
beaches, and removing aging docks at the
Wyckoff facility.
EPA is seeking public comment on this
proposed plan. The thirty-day public
comment period will run from June 8
through July 8, 1994. Verbal comments will
be accepted at a community meeting on
June 22 from 7 to 9 pm (see front page).
while written comments must be postmarked
by July 8 and sent to:
Ellen Hale
EPA Site Manager, Eagle Harbor
1200 6th Avenue, HW-113
Seattle, Washington 98101
More detailed information is available for
review as part of the administrative record
for the site at:
Region 10 EPA
1200 6th Avenue
Seattle, Washington
Tel: 553-1215
or
Bainbridge Public Library
1270 Madison Avenue North
Winslow, WA
Tel: 842-4126
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We encourage you to comment on all aspects
of the proposed plan for the East Harbor,
including the.alternatives evaluated, EPA's
preferred alternative, and the proposed
phasing of cleanup actions. Your comments
will help EPA make a technically sound
sediment cleanup decision that addresses
the concerns of the community. EPA will
consider all public comments on this
proposed plan. The final decision for the
East Harbor cleanup will be documented in
a Record of Decision (ROD). The East
Harbor ROD, together with EPA's 1992 ROD
for the West Harbor, will document all of
EPA's planned sediment cleanup activities
for Eagle Harbor.
SITE HISTORY
This proposed plan provides background
information about other parts of the site, such
as the West Harbor and the Wyckqfffacility,
but the cleanup alternatives and EPA's
preferred alternative apply only to the East
Harbor. EPA will continue to coordinate
activities among all of the operable units.
The Wyckoff/Eagle Harbor site, located on
Bainbridge Island, Washington, was listed as
a Superfund site for investigation and
cleanup of uncontrolled hazardous
substances in 1987. The site includes Eagle
Harbor and the former Wyckoff wood
treating facility. As shown in Figures 3 and
4, sediments in much of Eagle Harbor
contain hazardous substances such as
polynuclear aromatic hydrocarbons (PAHs)
and mercury. PAHs are a group of chemical
compounds found in creosote, used oil, and
other sources. Mercury and other metals in
sediment are often associated with
commercial marine practices such as
sandblasting and refurbishing boat bottoms.
Other substances have been detected, but
PAHs and mercury are the primary
contaminants of concern, due to their
toxicity to marine life, wide distribution, and
high concentrations in Eagle Harbor
sediments.
On the north shore of the harbor, ship
building, maintenance, and repair activities
were conducted from the turn of the century
into the late 1950's. These activities have
been identified as the primary source of the
Table 1
Operable Units at the Wyckoff/Eagle Harbor Superfund Site
Operable Unit (OU)
East Harbor
Wyckoff Facility
West Harbor
Wyckoff Groundwater
OUNo.
OU-1
OU-2
OU-3
OU-4
Description
Sediments near the
Wyckoff Facility
Soils at the Wyckoff
Facility
Sediments near the
former shipyard on the
north shore
Groundwater and
saturated soils at the
Wyckoff Facility
Current Phase
Partial cleanup completed,
public comment on
proposed plan for final
cleanup
Ongoing source control
actions and remedial
investigation field work
Design of 1992
cleanup decision
underway
Ongoing groundwater
treatment, remedial
investigation field work
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mercury and other metals found in the
harbor.
On the south shore, a succession of owners
operated a wood-treating facility from 1905
to 1988. Soils and groundwater in this area
contain compounds associated with wood
treating, particularly PAHs. The wood-
treating facility has been identified as the
primary source of PAH contamination in the
harbor.
In 1987, EPA made the Wyckoff/Eagle
Harbor site into two separate management
areas, known as operable units. This
allowed EPA to move forward with the
investigation of the harbor while taking
enforcement action to reduce PAH
contamination at the wood-treating facility.
Pacific Sound Resources, formerly Wyckoff
Company, began source control work at the
facility under a 1988 administrative order.
In December 1991, following completion of
the investigation of Eagle Harbor, EPA
issued a proposed plan for phased sediment
cleanup, separating the harbor into East
Harbor and West Harbor operable units.
RECENT SITE ACTIVITIES
A brief update of recent cleanup activities at
the site is provided below. This proposed
plan refers to two types o/Super/and cleanup
actions: removal actions and remedial
actions. Removal actions are used to
address imminent threats to human health or
the environment, while the remedial process
leads to comprehensive site cleanup. Both
types of actions apply to the Wyckoff/Eagle
Harbor site as described below.
Wyckoff Facility
At the Wyckoff facility, wood treating
operations ended in 1988. However, highly
contaminated soils, tank sludges, and .
groundwater presented a significant threat
to the harbor. To reduce sources, EPA
required the Wyckoff Company to implement
figure 3:
PAH Contamination
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a system to pump and treat contaminated
groundwater. The system has been in
operation since 1990. Contaminated
groundwater is pumped from on-site wells
and, once stripped of oily components, is
treated to meet stringent environmental
requirements. EPA assumed operation of
the groundwater treatment system in late
1993 and anticipates continued operation,
as well as system improvements.
In 1993 and early 1994, to further reduce
contaminant sources, EPA excavated and
disposed of contaminated sludges at the
facility; emptied, cleaned, and removed
asbestos-insulated pressure vessels and
chemical storage tanks; shored up a failing
bulkhead; and treated contaminated water
from runoff and storage tanks. These
actions were conducted under Superfund
removal authorities.
In February of this year, EPA began the
remedial study phase, collecting additional
data necessary to develop final soil and
groundwater cleanup plans for the Wyckoff
| "Figure 4:
Mercury Contaminaton
facility. Sampling of soil at different depths
will indicate soil characteristics and the soil
volumes which may require cleanup. Wells
and water samples will determine the depth
of groundwater contamination and support
an evaluation of potential contaminant
migration from the facility. Using the data,
EPA will assess risks to human health and
the environment and will develop soil and
groundwater cleanup alternatives for
evaluation by EPA and the public.
West Harbor
In the 1991 proposed plan for Eagle Harbor
EPA proposed a combination of cleanup
actions for the West Harbor tailored to the
degree of contamination and environmental
impact. It included the excavation of a
"hotspot" of mercury-contaminated
sediments near the former shipyard on the
north shore and a combination of capping,
thin-layer sediment placement and natural
recovery in less contaminated areas. EPA
considered public comments on the 1991
'',
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plan and issued a Record of Decision (ROD)
for the West Harbor in 1992. Currently,
PACCAR Inc., one of several potentially
responsible parties (PRPs), is designing the
West Harbor cleanup under EPA oversight.
The Washington Departments of
Transportation and Natural Resources are
also participating in the design phase.
Sediment sampling will take place in the
West Harbor this summer to better define
sediment cleanup volumes and areas.
Design drawings will be finalized in late
1995.
East Harbor
In 1991, EPA proposed an interim action in
the East Harbor focusing on the initial
cleanup of the most heavily contaminated
and biologically affected sediments.
Because the Wyckoff facility was a
continuing source of contamination to parts
of the East Harbor, EPA anticipated a later
cleanup proposal for remaining
contaminated areas of the East Harbor, after
sufficient information about sources from
the Wyckoff Facility was obtained.
EPA completed the proposed initial cleanup
in the East Harbor this winter using sandy
material to cover more than 50 acres of
contaminated bottom sediments. Based on
Information developed at Eagle Harbor and
at the Wyckoff Facility since 1991, EPA
believes it is now appropriate to propose a
final sediment cleanup plan for remaining
contaminated sediments in the East Harbor.
EAGLE HARBOR RISK ASSESSMENT
Under the Superjund remedial program, a
risk assessment is required to determine
whether cleanup action is warranted at a
site. The risk assessment for Eagle Harbor
was described in the 1991 Proposed Plan
and is briefly summarized again here.
EPA studied sediment and seafood
contamination and evaluated risks from site
contamination in the Remedial Investigation
(1989) and Supplemental Risk Assessment
(1991). Based on this evaluation, EPA has
determined that existing human health and
environmental risks warrant cleanup of the
sediments.
Environmental risk in Eagle Harbor is
indicated by adverse effects on organisms
that live on or in the contaminated
sediments. Liver and reproductive damage
in Eagle Harbor bottom fish are well
documented, and EPA tests show that the
contaminated sediments are toxic to
organisms such as small crustaceans and
oyster larvae, which are important indicators
of marine environmental health.
Contamination was found in fish, crab, and
clam tissues, indicating absorption of
contaminants through the food chain or
through direct contact with contaminated
sediments.
To assess potential cancer and non-cancer
human health risks, EPA used
measurements of Eagle Harbor sediments
and seafood and assumed lifetime exposure
to contaminants from eating contaminated
fish, shellfish, and sediments, and from skin
contact with contaminated beach sediments.
The primary human health risk was posed
by long-term, regular consumption of PAH-
contaminated crabs, clams, or other
shellfish from Eagle Harbor. Data also
suggested that a steady diet of Eagle Harbor
fish may pose a human health concern
Since 1985, the Bremerton-Kitsap County
Health District has maintained a public
health advisory cautioning against
consumption of fish and shellfish from Eagle
Harbor due to both chemical and bacterial
contamination. Warning signs are posted
around the harbor and the Health District
provides a telephone hotline recording
confirming the advisory.
Although a clean sediment cap has already
been placed over the most heavily
contaminated areas of the East Harbor, the
contamination in remaining areas of the
East Harbor is at a level anticipated to pose
a continued risk to marine organisms and to
people who may eat shellfish from beaches
adjacent to the Wyckoff Facility.
CLEANUP GOALS AND OBJECTIVES
EPA's mandate under the Superjund. law is to
protect human health and the environment.
Clean sediment provides a better habitat Jor
marine organisms and reduces contamination
-7 -
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auoiloble to the food chain. The objective of
this proposed plan is to address
contaminated sediments in the East Harbor
and to ensure that they meet state and
federal criteria for the protection of human
health and the environment.
EPA studied cleanup alternatives for two
general sediment zones:
Intertidal sediments: beach
sediments exposed at low tide, and;
Subtidal sediments: bottom
sediments below the low tide line.
Different environmental processes occur in
the intertidal zone, due to the presence of
air, light, and breaking waves. In addition,
intertidal sediments are readily accessible to
humans. For this reason, the potential for
human exposure to contamination in the
intertidal zone is greater.
Washington's Sediment Management
Standards
In Conducting Superfund remedial cleanups,
EPA is required to meet certain state and
federal regulations. These are referred to as
"applicable or relevant and appropriate
requirements" (ARARs). For Eagle Harbor,
the 1991 Sediment Management Standards
developed by the Washington Department of
Ecology constitute a significant ARAR. As
with the West Harbor, EPA has used the
state's sediment standards to develop a site-
specific cleanup objective for the East
Harbor.
The goal of the standards is to "reduce and
ultimately eliminate adverse effects on
biological resources and significant health
threats to humans from surface sediment
contamination." The standards include a
Puget Sound-wide approach for defining
sediment cleanup areas. Sediment data
from a given area are compared to a range of
contaminant levels provided by the
standards. Sediment contamination within
the range generally causes minor biological
effects. Sediments with contamination
greater than the range pose a significant risk
and must be included in a cleanup area,
while sediments cleaner than the range
require no further study.
For a given sediment site, a,cleanup
objective is selected from this range,
considering the environmental benefits, cost,
and technical feasibility of achieving the
objective through cleanup action. The
cleanup objective can be the most stringent
end of the range, defined by the Sediment
Quality Standards (SQS), the least stringent
upper end of the range, defined by the
Minimum Cleanup Level (MCUL), or
chemical levels within the range.
Although the chemical criteria are based on
the results of extensive chemical and
biological testing throughout Puget Sound,
the same level of contamination may not
always cause the same severity of biological
effects in all areas. If biological tests using
sediments from a given area prove the
contaminated sediments are not toxic, the
standards do not require cleanup of the
area. In addition, the standards recognize
that continuous natural processes such as
the breakdown of chemicals or their gradual
burial under newly deposited sediments are
a passive form of cleanup. For a given area,
if natural recovery will restore sediments to
the site objective within ten years, active
cleanup may not be required. Monitoring is
generally necessary to document the natural
recovery.
East Harbor Cleanup Objectives
For Eagle Harbor, EPA followed the process
of the state's sediment standards described
above to select an objective. EPA proposes
to use the MCUL as the primary cleanup
objective for the East Harbor. The MCUL
for PAH and Mercury are shown on Table 2.
In Eagle Harbor, many areas were
contaminated above the MCUL for one or
more contaminants (refer to Figures 3 and
4). Sediments were also tested for biological
effects. East Harbor areas which showed
high toxicity are now covered by the existing
sediment cap (refer to Figure 2); however,
remaining areas above the MCUL may pose
an environmental risk. EPA proposes to
address these areas with sediment cleanup,
unless further testing shows that adverse
biological effects are minor or are not
occurring.
-8-
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Active cleanup would not be required in
areas where sediment contamination levels
fall between the SQS and MCUL. Including
all sediments in this range would double the
estimated cleanup area. The costs and short
term environmental impacts of dredging,
capping, or other active cleanup in such a
large portion of the harbor might outweigh
the benefits of cleanup. In Eagle Harbor,
adverse biological effects were not
consistently observed where predicted by the
MCUL. Although some areas of the East
Harbor above the MCUL showed levels of
acute toxicity as predicted, other such areas
showed only minor of no acute effects. This
suggests that in areas cleaner than the
MCUL, the minor effects predicted may also
not be occurring.
Table 2
Puget Sound Marine Sediment Minimum
Cleanup Levels
Chemical Criteria*
dtiemical Parameter
1*AHs: (rag/kg organic carbon)
LPAH (total)
Naphthalene
Acenaphthylene
Acenaphthene
Fluorene
Phenanthrene
Anthracene
2-Methylnaphthalene
HPAH (total)
Fluoranthene
Pyrene
Benz(a)anthracene
Chrysene
Total Benzofluoranthenes
Benzo(a)pyrene
Indeno( 1 ,2,3-c,d)Pyrene
Dibenzo(a,h)anthracene
Benzo(g,h,i)perylene
MERCURY: (mg/kg mercury)
Criteria
780
170
66
57
79
480
1200
64
5300
1200
1400
270
460
450
210
88
33
78
0.59
* See the Washington Administrative Code
173-204-520 for a full listing and footnotes.
EPA believes that the MCUL is a cleanup
objective which effectively balances
environmental benefits, costs, and technical
feasibility for Eagle Harbor. The added
impacts and costs of addressing areas
cleaner than the MCUL is not justified
because biological effects of contamination
in such areas are minor or absent. Active
cleanup of areas above the MCUL may
enhance the natural recovery in less
contaminated areas.
How the MCUL will be applied in East
Harbor SUBTIDAL areas
EPA proposes active.cleanup in East Harbor
subtidal areas failing the MCUL chemical
criteria, except where full biological testing
shows only minor adverse effects. Once
final cleanup areas above the MCUL are
defined with updated sampling data, there
would be no evaluation to determine whether
further natural recovery is likely.
Because East Harbor sediment cleanup
actions hinge upon further source control at
the facility, it may be several years before
final cleanup begins. By this time, six te ten
years may have elapsed since the initial
collection of sediment data in 1988.
Although eliminating subtidal areas
predicted to recover naturally could reduce
the cleanup costs, EPA believes that waiting
ten additional years is unacceptable.
How MCUL will be applied in East Harbor
INTERHDAL areas
In the East Harbor, EPA predicts natural
recovery of PAH-contaminated intertidal
sediments because conditions for natural
recovery of PAHs are better in intertidal
zones than subtidal. Exposure to light
accelerates the chemical breakdown of
PAHs, and the availability of oxygen
enhances microbial breakdown.
This approach is similar to the 1992 cleanup
decision for the West Harbor, which called
for control of PAH sources (such as pilings
and runoff from paved areas) and for
monitoring to document the predicted
recovery of intertidal sediments near the
ferry terminal. As in the West Harbor,
contaminated intertidal sediments adjacent
to Wyckoff would be required to meet both
-9-
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the MCUL and a cleanup objective for
carcinogenic high-molecular weight PAHs
(HPAH) of 1200 parts per billion. The MCUL
protects the marine environment, while the
HPAH objective is intended to reduce public
health risk from carcinogenic PAHs in the
tissue of shellfish. EPA proposes to use
fencing, signs and other public outreach to
limit shellfish harvest from contaminated
intertidal sediments adjacent to the Wyckoff
Facility. Monitoring will be necessary to
document reductions in PAH contamination.
EPA recognizes that the West Harbor and
East Harbor intertidal zones differ in ways
that may make it difficult to achieve the
cleanup objectives. Contamination of the
West Harbor intertidal sediments came
primarily from surface sources, such as
creosoted wood structures and runoff from
paved surfaces. Control of surface sources
is a definable point when monitoring of
natural recovery can begin. In the East
Harbor, however, years of oily seepage on
the beach have led to greater levels of
contamination over a greater depth. Even
once seepage from the facility is controlled,
coptamination ih underlying sediments may
be forced up into surface sediments through
tidal action. This could affect the potential
for either active cleanup or natural recovery
to achieve the cleanup objectives. If
monitoring or pilot studies indicate that
sediments are unlikely to achieve the
objectives within ten years after source
control, EPA will consider active measures,
such as enhancing the breakdown of PAHs
or excavating heavily contaminated
sediments. Cleanup of any excavated
sediments would be coordinated with
Wyckoff Facility soil cleanup.
SOURCE CONTROL
A major factor in any cleanup decision is
control of contaminant sources. If sources
are not sufficiently controlled,
recontamtnation after cleanup can occur.
For the East Harbor the primary source of
contamination is the Wyckoff facility. Active
wood-treating operations ceased in 1988
and cleanup work at the facility has
continued to reduce sources to Eagle
Harbor. However, ongoing sources of
contamination may still affect remaining
areas of the East Harbor.
The existing cap in the East Harbor was
warranted by the documented biological
effects of the heavy contamination in this
area, and was placed in areas away from
active oily seeps. Oily seeps and
groundwater moving from the Wyckoff wood-
treating facility may continue to affect areas
adjacent to the facility for some time.
Phased Sediment Cleanup
For the above reason, EPA's preferred
cleanup approach for the East Harbor links
sediment cleanup to source control at the
Wyckoff facility. Table 3 on the next page
shows an estimated timeline for cleanup
actions at the East Harbor, Wyckoff facility,
and West Harbor. Over the next several
years, EPA anticipates further source control
due to (1) improvements to the existing
groundwater extraction and treatment
system (2) evaluation and selection of soil
and groundwater cleanup alternatives for
the facility, and (3) design and construction
of the selected facility cleanup alternative.
During this time, EPA proposes to conduct
yearly evaluations. When data from the
facility and from sediment monitoring
indicate that source control is sufficient,
design and implementation of East Harbor
sediment cleanup would proceed.
Other Necessary Actions
Although this proposed plan focuses on
cleanup alternatives for remaining
contaminated sediments, certain other
actions may be necessary to protect the
existing sediment cap and to assure public
safety. EPA proposes these actions in
addition to the sediment cleanup options
described in this proposed plan. The area of
the East Harbor recently covered with clean
sediment would be monitored to assure that
the cap remains clean, to observe re-
colonization by marine organisms, and to
evaluate its physical integrity. Limited
monitoring in other areas may be necessary
to document changes in sediment
contamination, evaluate the status of source
control, and assess the potential for natural
recovery.
-10-
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Table 3
Tentative Schedule for Proposed Actions in the East Harbor
WYCKOFF FACILIlV
rfBx
V Actions! j
i
H c^ewtlontfgrpna^^ H O&M
SJiiiltM* ftt*mf
f
EAST HARBOR
Placement
ofFxisting
Sediment
Cap
!Jl7I?Crrl UA DTif~lD
WU/o 1 HAKliUK
rSitaST- *R«fl
Sediment * DCS
Cleanup *Defl
Decision >fctti
Pre-1992 1992 1993
'va«|
:^SS^
L N
s
\
Final
. Sediment
Cleanup
Decision
r^
«T
^
Ine Cleanup Arjea
Ign eieahujf* - ;|; - '
lnefiasellnef&£
; CJeattUpV.,
ty&shM-
: i'trVM
%'*,&*
m'ot >" ' -' ','.'" Construction
ff .f ' f*\ Oy. **
blip ' " ' , orCleanup ,
^ Increasing Source Control
(scl
* Determinatlo
Sediment Cleanup Actions:
ledule will depend upon achievement of source control goals)
Refin
Desig
Defin
Natui
Implement Monitoring,
e Cleanup Area |~ Subtidal Cap ~ O&M (10 yrs)
n Cleanup
e Baseline for
ral Recovery Monitor Intertidal Natural
Recovery (10 yrs)
n made on the basis of yearly evaluations of harbor and facility data
Other Necessary Actions:
Monitoring Dock Demolition
Institutional Armoring
Controls
f ft Sf '
f r , / f ftS f f
iiiiriiiiiiuMtui
' / "'' ,/
'; 'j* '^, ' ,
;; Monitor NafMralRfctover^
(lpy«arsj,__ j t ' *
"" /'"" ' ' CoJcd
1994 1995 1996
Approximate
%$«&:
1997
Timefran
s
,,1 , -, Monitorlhg/O & M (i« Years)
1998 1999 2000 2001 2002 **^
ie
-------
Currents created by ferry traffic may cause
some loss of sandy material from the
existing sediment cap. EPA monitoring over
the next several years may identify areas
where "armoring" (adding a layer of gravel or
larger materials to hold the sand in place) is
necessary or where additional cap materials
should be placed. This work would proceed
as necessary.
In addition, EPA proposes to demolish
creosoted wood docks, piers and pilings at
the inactive Wyckoff Facility. The piers pose
a potential public safety hazard in their
current condition, and their deterioration
over time will release more PAHs into the
harbor. Removing the structures prior to
final sediment cleanup will also make it
easier to monitor and clean up sediments
close to shore.
Estimated costs for monitoring, armoring
areas of the cap, and the demolition and
disposal of treated wood structures range
from $2 to $5 million as shown below.
Actual costs depend on the time it takes for
source control, how large an area (if any)
ne§ds armoring,>and whether debris from
the dock demolition requires disposal at a
hazardous waste landfill.
Monitoring: $100 thousand per year
(estimate minimum of 3 yrs)
Armoring: $0.5 - 1 million (estimate of
8-11 acres)
Demolition: $1.5-3 million
SEDIMENT CLEANUP ALTERNATIVES
EVALUATED
In the Eagle Harbor Feasibility Study (FS),
EPA evaluated several technologies JOT
cleaning up Eagle Harbor sediments. This
section provides an overview of the cleanup
alternatives considered. Specific alternatives
are described on pages 15-16. For more
detailed information about the alternatives,
the FS is available for review at the EPA
office in Seattle or at the public library in
Bainbridge.
The FS outlined preliminary cleanup areas
and compared effectiveness, cost, feasibility.
and other factors for the technologies which
could be used in each cleanup area. The
alternatives were summarized and compared
in the 1991 proposed plan.
EPA's 1992 cleanup decision for the West
Harbor combined excavation of a sediment
hotspot with capping, while the partial
cleanup for the heavily contaminated areas
of the East Harbor was completed with a
sediment cap. The following section
summarizes the cleanup alternatives
evaluated for remaining contaminated areas
of the East Harbor. A summary of EPA's
comparative analysis is provided at the end
of this Proposed Plan.
Overall cleanup alternatives fall into three
categories:
* no action,
»institutional controls, and
» active cleanup.
Under the Superfund remedial program, EPA
always considers, the "no action" alternative
in developing a feasibility study. Even if no
action would result in unacceptable risks,
this alternative must be compared with other
alternatives to weigh the benefits of
institutional controls or active cleanup. In
some cases, even without active cleanup?
natural processes contribute to gradual
environmental recovery.
Public awareness programs, fences, warning
signs, and land use restrictions are
examples of institutional controls. These
can reduce or eliminate access or exposure
to contaminants but do not clean up the site
or protect marine organisms.
Active cleanup options are engineered
solutions to site contamination. For East
Harbor sediments, EPA evaluated a number
of active cleanup alternatives. Only one,
capping, would cover the contaminated
sediments where they lie. All of the other
active options involve dredging of
contaminated sediments and management of
these dredged sediments. Dredged,
contaminated sediments could be contained
in engineered facilities at the harbor bottom
or near shore. Alternatively, dredged
sediments could be treated through
incineration or biological treatment, both of
which require de-watering, storage, and
management of waste water and the treated
sediments.
-12-
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Areas, Costs, and Timeframes
In the FS, EPA used available chemical and
biological data collected by EPA in 1988 to
estimate cleanup areas throughout Eagle
Harbor. Separate estimates were developed
for intertidal and subtidal areas. For
subtidal areas, a range of areas was
estimated to show how changes in cleanup
areas might affect the costs.
The FS cost estimates are provided in Tables
4 and 5 for comparison of the relative costs
of different sediment cleanup alternatives.
The $2 to $5 million estimated for other
necessary actions described above would be
in addition to these costs.
It is important to note that cleanup of East
Harbor sediments would not begin until
sources of contamination to the East Harbor
from Wyckoff are sufficiently controlled,
potentially several years from now. Prior to
detailed design of the sediment cleanup,
additional sampling would be conducted to
refine cleanup areas. Due to reduced
seepage from Wyckoff, microbial breakdown
of PAHs, and th« spreading of clean
sediments at the edge of the partial cap in
the East Harbor, contaminant levels may
have decreased. This could result in
reduced cleanup areas and corresponding
reductions in costs.
The description of each alternative includes
a timeframe for design and implementation
of the alternative, based on the estimated
areas and volumes. These timeframes do
not include the timepotentially several
yearswhich may be necessary before
ongoing and planned cleanup at the Wyckoff
facility have sufficiently controlled sources of
contamination to the East Harbor. When
remedial design is initiated, changes in
estimated cleanup areas may shorten the
estimated timeframes for implementation.
Common Elements of the Cleanup
Alternatives
The alternatives described below share
certain elements. Each alternative,
including "no action," would require
monitoring to evaluate changes in .
environmental conditions after active
cleanup or through natural processes. For
the cleanup alternatives other than no
action, EPA would link implementation of
final sediment cleanup with further source
control at the facility. Cap monitoring and
other work described under "Other
Necessary Actions" would supplement all
alternatives other than no action.
In addition, all active cleanup alternatives
would require the following: sampling during
the design phase to refine estimates of
cleanup areas or volumes; completion of
detailed design plans; and mitigation for
any significant habitat lost as a result of
active cleanup.
During remedial design, EPA may find it
necessary to modify cleanup boundaries and
methods somewhat, due to steep slopes in
areas of the harbor or to the presence of
sensitive eel grass habitat. Subtidal slopes
on the eastern side of the Wyckoff facility
range up to 15%. Capping can be difficult
on slopes of this nature, while dredging
could expose more contaminated sediments.
Special methods and/or changes in the
scope of cleanup would be necessary if the
final cleanup areas included such steeply
sloped conditions. Between the tideline and
minus thirty feet, eel grass has been noted
in some areas, and may be widespread. If
remedial design sampling indicated that
healthy, productive eel grass beds fell near
or within cleanup areas, EPA and other
resource agencies would need to evaluate
ways to avoid or mitigate impacts from
cleanup. As replanting is often
unsuccessful, these areas could be left
alone, with monitoring to observe natural
recovery.
Monitoring of the East Harbor after cleanup
would continue as necessary to assure that
the cleanup is successful and to verify
reductions in seafood contamination. EPA
estimated up to thirty years of monitoring,
which would be included as part of
operations and maintenance (O & M).
- 13-
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Table 4
Estimated Costs" of East Harbor Cleanup Alternatives
Evaluated in Feasibility Study
INTERTIDAL SEDIMENTS
Estimated Costs in Dollars
Based on FS Intertidal Area* of 55,000 m2 (14 acres)
Alternative
Initial
O&M
Total
No Action/Natural Recovery M 0^ 300,000
Institutional (^ntrols/NaiiiralRecovery 24*OOO I;! 376,000
Capping 5,900,000 600,000
Confined Aquatic Disposal 9,800,000 800,000
Nearshore Confined Disposal 29.500,000 1,500,000
Incineration 99,200.000 2,800,000
Biological Treatment 71,500,000 1,900,000
300,000
400,000
6,500,000
10,600,000
31,000,000
102.000,000
73.400,000
Table 5.
Estimated Costs' of East Harbor Sediment Cleanup Alternatives
' Evaluated in Feasibility Study
SUBTIDAL SEDIMENTS
Costs in Dollars Based on FS Lower Bound Area0 of 235,000 m2 (58 acres)
Alternative
No Action/Natural Recovery
Institutional Controls/Natural Recovery
Capplag
Confined Aquatic Disposal
Nearshore Confined Disposal
Incineration
Biological Treatment
Initial
0
0
13,700,000
26,600,000
46,700.000
238,700,000
176,000.000
O&M
300,000
400,000
800,000
1,300,000
1,000,000
5,200,000
4,000,000
Total
300,000
400,000
14,5OO,OOO
27,900,000
48,600.000
243,900.000
180,000.000
' Initial capital costs are based on 1990 dollars, and present worth of O&M was calculated using an 8% discount rate
and a 30-year amortization period.
" Intertidal costs are based on 55,000 square meters, an area which includes 40,000 square meters of intertidal sediments
in the East Harbor and 15,000 square meters in the West Harbor. Actual costs would be lower, but relative costs would not
change significantly.
' Estimated costs are based on areas developed for the Feasibility Study, for lower bound cleanup areas. This estimate
is close to the estimated area of sediments not included in the capped areas of the East Harbor but which fail one or
more of the MCUL chemical criteria (259,000 m2)- Areas outside the existing cap which fail one or more of the SQS
chemical criteria are estimated at 488,000 m2, approximately double the lower bound areas. Estimated costs for addressing
these are provided in the FS, as upper bound cost estimates. Generally, cleanup costs would approximately double.
- 14-
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DESCRIPTION OF CLEANUP
ALTERNATIVES
No Action/Natural Recovery
Under "no action," the East Harbor would be
left in its present condition to recover over
time through natural processes such as
sedimentation (settling of sediment from the
water column), chemical and biological
breakdown of PAH, and dispersal of
contaminated sediments. The combined
effect of these processes is known as natural
recovery.
Eagle Harbor has little new sedimentation,
and it can take decades for certain PAH
compounds to degrade in subtidal
conditions. Based on 1988 chemical data,
EPA estimates that even with complete
source control, it could take several decades
for heavily contaminated subtidal areas to
achieve the MCUL. PAHs exposed to light
and air break down faster, and surface
sediments in beach areas are predicted to
meet the state standards in ten years
without active cleanup, if all sources to
those sediments are controlled.
The estimated costs for thirty years of
monitoring fish and shellfish tissue,
sediment chemistry, and biological effects
are included in Tables 4 and 5.
Institutional Controls/Natural Recovery
Institutional controls could include fencing
contaminated beach areas, restricting
commercial fish and/or shellfish harvests,
and posting additional advisory signs to
supplement the existing health advisory.
These actions would further limit exposure
of humans to contaminated seafood and
sediments. Marine organisms would
continue to be exposed to contamination
until the sediments recovered naturally as
described above. For the purpose of
estimating costs, periodic monitoring of fish
and shellfish tissue, sediment chemistry,
and biological effects were assumed to
continue for thirty years. It would take less
than a year to implement the controls.
Capping in Place
Capping involves covering contaminated
sediments with clean material. In heavily
contaminated subtidal areas of the East
Harbor, a three-foot thick sand cap has
already been placed. Capping limits
movement of contaminated sediment,
isolates the contaminants from the marine
environment, and provides clean habitat for
sediment-dwelling organisms.
Although Eagle Harbor is a protected harbor
with relatively slow currents, ferry propeller
wash and currents along the east shore at
the mouth of the harbor may be strong
enough to erode sandy cap material in some
areas. In such areas, including portions of
the harbor already capped, gravel or coarser
materials may be needed as "armoring" on
the sandy layers to keep the cap in place, or
additional sand may be added to maintain
the cap thickness.
An effective cap would have to be designed
for long-term stability, especially in intertidal
areas where waves and currents present
higher energy conditions; "armoring" with
coarse materials could address this concern.
Where slopes are steep, it may be
impracticable to place a full three feet of
material; however, sufficient material could
be placed to enhance recovery in the top 10
centimeters of sediment, the most
biologically active zone. Design and
implementation of capping are estimated to
take 2-4 years.
Confined Aquatic Disposal
This alternative would involve dredging
contaminated sediments from the subtidal
and intertidal zones, placing the sediments
in a pit dredged at the bottom of Eagle
Harbor for a confined aquatic disposal (CAD)
facility, and covering the relocated sediments
with clean sediment originally dredged to
make the CAD facility. The FS considered
an area in the central channel of the East
Harbor for a CAD facility. The top of the
CAD area would be level with the harbor
bottom, and excess clean sediment would be
disposed of at an approved open water site.
Contaminated sediments removed from
intertidal areas would be replaced with clean
material to replace disturbed intertidal
- 15-
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habitat. Design and implementation could
take 4-6 years.
Nearshore Confined Disposal
This alternative calls for constructing a
sediment containment area in the harbor
adjacent to the shore. Contaminated
sediments would be dredged from subtidal
and intertidal areas, placed in the
containment area, and capped with clean
sand. The containment area surface would
be an extension of the existing land surface.
Areas considered for such containment
include, for example, the log-rafting area
near the Wyckoff facility. Leaching controls
and monitoring would be necessary. Design
and implementation are estimated to take
4-5 years.
Incineration
For this alternative, contaminated sediments
would be dredged, dewatered, processed to
break up larger particles, and incinerated.
The incinerator,>a mobile rotary kiln or other
design, would be equipped with air pollution
control equipment. The incinerator could be
located at the Wyckoff facility or elsewhere
within the site boundaries. Incinerator
residue would be disposed of in accordance
with state and federal regulations. After
burning, the sediment would be disposed of
either in an open water disposal site or at an
approved landfill, depending on the nature
of remaining materials. Design and
implementation are estimated to take 8-11
years.
Biological Treatment
Contaminated sediments would be dredged
and, after dewatering, mixed in a slurry,
aerated, and passed through a biological
treatment system over time to break down
PAH and other organic contaminants.
Biological treatment tanks, which could be
located on the Wyckoff property, would be
equipped with pollution controls. The
treated sediment would have to demonstrate
compliance with standards for open-water
disposal, and waste water from the process
would be biologically treated on site. Design
and implementation are estimated to take
9-11 years.
EPA's PREFERRED ALTERNATIVE
EPA's preferred alternative would combine
two of the above alternatives to achieve the
sediment cleanup objectives: capping in
place for subtidal sediments, and
institutional controls/natural recovery for
intertidal sediments.
Under the preferred alternative, the
sediment cap placed under Superfund
removal authorities would be incorporated
as a component of the final remedy, as
would the proposed phasing and the other
necessary actions described on page 10.
The subtidal cap would be extended into
remaining subtidal areas contaminated
above the Minimum Cleanup Level (MCUL),
and would be modified as necessary to
address steeply sloped areas and sensitive
eel grass habitat.
Intertidal areas near the Wyckoff Facility are
expected to achieve the intertidal cleanup
objectives without active cleanup in ten
years or less after control of significant
sources. A fence and signposts at the
beaches adjacent to the facility would be
used to discourage harvest of shellfish. ~If
necessary, active cleanup measures, such as
nutrient enhancement or hotspot excavation,
would be evaluated to ensure that intertidal
areas achieve the cleanup objective.
Excavated sediments could be handled in
conjunction with the Wyckoff Facility soil
cleanup.
The cost for sediment cleanup under the -
preferred alternative as estimated in the FS
is $15 million, including $0.4 million for
institutional controls/natural recovery (see
Table 4) and $14.5 million for capping in
subtidal areas (see Table 5). This includes
design and construction of a cap, fencing
and other institutional controls, and long-
term monitoring.
As with the other active alternatives, the
demolition of docks at the Wyckoff facility,
monitoring of sediments, and armoring of
the existing cap (if necessary) could add up
to $5 million (refer to "Other Necessary
Actions", page 11). This would bring the
total cost range for all proposed actions in
the East Harbor to an estimated $6 to $20
million.
- 16-
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While the $14'.5 million for capping areas
currently estimated to be above the MCUL
(shown in Table 5) reflects a maximum cost
estimate, a number of factors could result in
lower capping costs. Updated EPA estimates
are as low as $7 million.
In addition, definition of the cleanup areas
after source control at the Wyckoff facility is
likely to result in smaller cleanup areas and
corresponding cost reductions. Finally,
sediments available at low cost from planned
navigational dredging projects in clean Puget
Sound locations may also decrease costs, as
they did with the existing East Harbor cap.
Thus. EPA expects that final costs should
approach the low end of the cost range.
WHAT'S NEXT?
A community meeting about this plan will be
held as indicated on the front of this
document. The meeting will be an
opportunity for you to ask questions about
the proposed plan and to provide your
comments in person.
>
EPA will respond to written and verbal
comments on the proposed plan in a
document called a "responsiveness
summary." After considering all public
comments, EPA will make the cleanup
decision for the East Harbor and will
document the decision in a Record of
Decision (ROD), with the responsiveness
summary attached. The ROD will be
available for review at EPA and the public
library in Winslow.
Once the ROD is signed, EPA may enter into
negotiations with the potentially responsible
parties to implement the selected cleanup.
Implementation includes necessary testing
and detailed engineering design before
actual cleanup action begins. To ensure the
continued protectiveness of Superfund
cleanups where contaminants remain on
site, EPA requires a review every five years
after cleanup activities begin.
The information summarized in this
proposed plan is explained in greater detail
in the Eagle Harbor Remedial Investigation
and Feasibility Study, as well as in several
technical memoranda. These documents are
available for public review as part of the
administrative record file for the site, at the
locations listed on page 2.
QUESTIONS?
contact:
Ellen Hale
EPA Project Manager
(206) 553-1215
or
Ken Marcy
EPA Community Relations Coordinator
(206) 553-6501
Call EPA toll-free at 1-800-424-4EPA
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APPENDIX
COMPARISON OF THE ALTERNATIVES
The alternotiues in the FS tuere evaluated
based on the nine evaluation criteria
described in Table 6. EPA believes that the
preferred alternative provides the best
balance of tradeoffs among the alternatives
with respect to the nine evaluation criteria.
The following is a summary ofEPA's
evaluation.
Protectiveness of Human Health and the
Environment
All cleanup alternatives except No Action
and Institutional Controls protect human
health and the environment.
Treatment alternatives would achieve long
term protection with few monitoring
requirements. Alternatives involving on-site
containment of contaminated sediments
would require long-term monitoring and
maintenance inprder to assure continued
protection. No Action/Natural Recovery
could be protective of the environment once
sediments reached the cleanup objective, a
This alternative would not address process
that could take more than ten years. This
alternative would not address human health
concerns. Institutional Controls/Natural
Recovery could provide protection of human
health until the sediments recovered to
cleanup levels.
EPA's preferred alternative is protective of
both human health and the environment. In
conjunction with the existing health
advisory, institutional controls (fencing, and
warning signs at the Wyckoff Facility beach)
will discourage consumption of
contaminated seafood. Natural recovery (or
other active measures as needed) will ensure
that environmental protection is achieved
within ten years of source control. Capping
of subtidal sediments isolates contamination
from marine organisms. Monitoring and
maintenance will be needed.
Compliance with ARARs
All alternatives except No Action and
Institutional Controls could comply with
ARARs.
Certain ARARs regarding waste management
would apply only for alternatives involving
dredging or treatment alternatives but would
not apply to capping in place, natural
recovery or institutional controls. No Action
and Institutional Controls would meet not
meet the primary ARAR of the state sediment
management standards, except for areas
where natural recovery could occur in ten
years.
EPA's preferred alternative meets all ARARs.
Long-Term Effectiveness and Permanence
Biological Treatment and Incineration
permanently destroy PAH and other organic
compounds. For highly concentrated
contaminants that are mobile in the
environment, Superfund policy generally
favors on-site treatment options over
containment, institutional controls, or off-
site disposal of untreated waste. However,
containment options can be designed to-
provide long-term effectiveness and
permanence in certain cases.
Containment alternatives (confined aquatic
disposal, nearshore disposal, or capping in
place) are most appropriate for large
volumes of waste with relatively low
contaminant concentrations, as with many
contaminated sediment sites. Containment
alternatives require maintenance to be
effective long term.
No action and institutional controls do not
permanently affect the conditions at the site,
except where sediments recover naturally
over time.
The preferred alternative combines capping
and natural recovery, with provisions for
demolition of creosote-treated structures and
active remediation of some intertidal
sediments. EPA believes this balances the
need for containment of large areas of
moderately contaminated sediments with the
flexibility to take a more aggressive
approach in source areas or hotspots. If
sediment hotspots are excavated from the
intertidal zone, they could be treated,
contained, or disposed, depending on the
cleanup selected for the facility soils.
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Longterm monitoring and maintenance of
the capped areas would be necessary to
verify effectiveness.
Reduction of Toxicity, Mobility, and
Volume
Biological treatment and incineration would
directly reduce the toxicity and mobility of
PAH contamination.
Containment alternatives do not alter the
chemical nature of the contamination, but
restrict the movement of sediment particles
to which organic contaminants are bound.
No Action and Institutional Controls do not
directly affect toxicity, mobility, or volume,
but natural processes could reduce the
toxicity and volume over time.
Table 6:
The preferred alternative does not directly
affect toxicity, mobility, and volume, but in
intertidal zones these processes should
occur naturally. Movement of subtidal
contaminated sediments would be restricted
by capping.
Short-Tenn Effectiveness
Alternatives involving treatment (such as
biological treatment or incineration) take
more time to implement. Engineered
containment facilities (such as nearshore or
confined aquatic disposal facilities) could be
completed sooner. Capping with clean
sediment provides the greatest short-term
effectiveness because it can be implemented
most readily. Institutional controls can be
implemented within a year. No action
Evaluation Criteria
EPA uses nine criteria to identify its preferred alternative for a given site or contaminant. With the exception of the
no action alternative, all alternatives must meet the first two "threshold" criteria. EPA uses the next five criteria as
"balancing" criteria for comparing alternatives and selecting a preferred alternative. After public comment, EPA may
alter its preference'on the basis of the last two "modifying" criteria. _
Threshold Criteria:
1. Overall Protection of human health and the environment - How well does the alternative protect human health
and the environment, both during and after construction:
2. Compliance with federal and state environmental standards - Does the alternative meet all applicable or
relevant and appropriate state and federal laws?
Balancing Criteria:
3. Long-torn effectiveness and performance How well does the alternative protect human health and the
environment after completion of cleanup? What, if any, risks will remain at the site?
4. Reduction of toxicity, mobility, or volume - Does the alternative effectively treat the contamination to
significantly reduce the toxicity, mobility, and volume of the hazardous substance?
5. Short-term effectiveness - Are there potential adverse effects to either human health or the environment during
construction or implementation of the alternative? How fast does the alternative reach the cleanup goals?
6. Implementability - is the alternative both technically and administratively feasible? Has the technology been used
successfully on other similar sites?
7. Cost - What are the estimated costs of the alternative?
Modifying Criteria:
8. State acceptance - What are the state's comments or concerns about the alternatives considered and about EPA's
preferred alternative? Does the state support or oppose the preferred alternative?
9. Community acceptance - What are the community's comments or concerns about the preferred alternative? Does
the community generally support or oppose the preferred alternative?
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requires the least implementation but is not
effective in the short term.
Short term impacts of cleanup alternatives
on the environment and human health must
also be considered. Treatment and
containment alternatives that require
dredging of contaminated sediments risk
suspension of contaminated sediments and
exposure of marine organisms and humans
to the sediments. Capping can be done with
minimal short-term environmental impacts,
as demonstrated with the existing cap in the
East Harbor.
Studies show that marine organisms soon
repopulate clean sediment. This process
has already begun in areas of the East
Harbor addressed last winter by the cap.
Recolonization by these organisms can begin
immediately after capping or removal of
contaminated sediments, but development of
a mature community of sediment-dwellers
may take two years or more. Small cleanup
areas can be recolonized by organisms from
adjacent clean sediments. Monitoring
during placement of the existing East Harbor
cap shows that buildup of cap thickness in
shallow layers allows some organisms living
in the contaminated sediments to survive by
moving upwards into the clean material.
The preferred alternative minimizes impacts
on the intertidal zones by allowing natural
recovery over ten years. If excavation is
needed, suspension of contaminated
sediments can be minimized by working at
low tide. In subtidal areas, capping can be
implemented readily and provide protection
of the marine habitat.
Implementability
All alternatives require careful design,
scheduling, and environmental monitoring,
as well as coordination with ferry traffic. All
can be implemented, although with varying
degrees of difficulty. Treatment options
require storage, extensive processing of
sediments, and the management of sediment
and drained water. Evaluating a suitable
containment site within Eagle Harbor would
require study and complex staging of
dredging and transportation activities.
Capping in place requires less complex
engineering controls to limit water column
releases than options which involve
dredging, such as treatment or confined
disposal.
Institutional controls require coordination
with state and local entities.
The preferred alternative is readily
implemented. Capping and institutional
controls/natural recovery involve no
dredging, storage, dewatering, or processing
of contaminated sediment. If hotspots are
excavated from the intertidal zone, the
sediments can be managed in coordination
with soil cleanup at the facility.
Cost
The estimated cost range provided with each
alternative assumes the alternative is
applied wherever feasible and appropriate,
given the contaminants and physical
location. Actual cleanup costs could be less
if cleanup areas are smaller than current
EPA estimates. In general, initial costs for
treatment options and disposal options-are
high. Containment costs tend to be lower
initially, with higher monitoring and/or
maintenance costs. Institutional controls
are usually the least costly. The preferred
alternative combines containment (by
capping) in place, natural recovery, and
institutional controls.
Comparing total costs for applying each .
alternative in both intertidal and subtidal
areas, incineration would be the most costly
(approximately $345 million). Costs would
be somewhat lower for biological treatment
(approximately $255 million), and would
decrease further for containment options
such as Nearshore Disposal ($78 million)
and Confined Aquatic Disposal ($30 million).
Capping is the least costly active cleanup
alternative (estimated at $20 million).
Institutional controls ($0.8 million) and No
Action ($0.6 million) are the least costly
alternatives, but would not meet the cleanup
objectives.
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EPA's preferred sediment cleanup alternative
combines subtidal capping ($14.5 million)
with institutional controls/natural recovery
($0.4 million) for intertidal sediments, for a
total estimate of $15 million for sediment
cleanup.
Other necessary actionsmonitoring, dock
demolition, and cap armoring (if necessary)--
could add up to $5 million to each of the
alternatives, including the preferred
alternative. In the case of the preferred
alternative, this would bring the maximum
cost for all proposed actions in the East
Harbor to an estimated $20 million.
As noted in the discussion of the Preferred
Alternative (page 16), EPA anticipates that
the actual costs of capping will be
significantly reduced.
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3EFA
United States Region 10 (HW-117-CR)
Environmental Protection 1200 Sixth Avenue
Agency Seattle WA 98101
Wyckoff/Eagle Harbor
East Harbor Proposed Plan
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APPENDIX B
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Responsiveness Summary
1994 Proposed Plan for Final Cleanup
East Harbor Operable Unit
Section four of the East Harbor Record of Decision (ROD) describes community relations activities
leading up to the ROD. As noted, the Environmental Protection Agency (EPA) issued a Proposed Plan
in 1991 for Eagle Harbor sediment cleanup, proposing final action in the West Harbor and interim action
in the East Harbor. A second Proposed Plan was issued in 1994 after the interim action in the East
Harbor was completed.
This responsiveness summary provides EPA responses to comments on the 1994 Proposed Plan only.
EPA's response to comments on the 1991 Proposed Plan was attached to the 1993 Action Memorandum
documenting EPA's decision to use Comprehensive Environmental Response, Compensation, and Liability
Act (CERCLA) removal authorities for the interim action. Because the interim action has been
incorporated in the final selected remedy for the East Harbor, the responsiveness summary for the 1991
Proposed Plan is also included, as Attachment A.
Comments on the 1994 East Harbor Proposed Plan were provided at a public meeting and in five letters
to EPA. Letters were received from the Washington Department of Natural Resources (DNR), the
Technical Advisory Committee of the Association of Bainbridge Communities (ABC), two individual
members of ABC, Pacific Sound Resources (PSR, aka the Wyckoff Company), and an unaffiliated
citizen. Overall, comments supported the proposed final remedy. Several comments requested
clarification of issues in the ROD or proposed minor changes in the EPA's approach.
EPA has grouped the comments under the following headings:
Cleanup objectives,
Cleanup alternatives,
Implementation of the selected remedy, and
Other Issues.
Paraphrased comments and EPA responses are provided below, under these headings.
1. Cleanup Objectives
Comment: Why is a ten-year natural recovery period acceptable in intertidal areas, but unacceptable in
subtidal areas? The intertidal areas are more likely to be used by the general public.
EPA Response.- Contamination by polynuclear aromatic hydrocarbons (PAHs) in the East
Harbor is most amenable to natural recovery in intertidal areas, and there is a strong likelihood
that natural recovery will be effective in these areas due to sunlight and wave action. Unlike
subtidal habitat, intertidal habitat is sensitive to changes in elevation. Elevation changes due to
capping or excavation can be avoided where natural recovery is predicted. During the sediment
recovery period, human exposure in intertidal areas will be minimized by institutional controls
(warning signs, access restrictions) at the beaches adjacent to the Wyckoff Facility. In subtidal
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zones, natural recovery processes will be relied on in areas contaminated below the minimum
cleanup level (MCUL). However, since subtidal areas are less affected by elevation changes, the
impacts of active cleanup are less significant. However, the ROD allows limited consideration
of natural recovery where cleanup would damage valuable habitat, consistent with the intertidal
zone, or where capping is technically impracticable. Conversely, active remediation is provided
for in intertidal zones, in specific areas where natural recovery may not achieve cleanup
objectives.
2. Cleanup Alternatives
Comment: EPA should ensure effective institutional controls by public education efforts and by posting
and maintaining signs visible not only at the property boundary on the beach but along the beach, to
notify approaching boaters.
EPA Response; EPA agrees that signs should be posted at intervals along the beach, in case they
approach by boat. Although such signs are already posted, larger signs may be more effective.
The need for maintenance of the warning signs and other institutional controls is acknowledged.
Comment: Institutional controls to restrict beach access at Wyckoff should be implemented as soon as
possible.
EPA Response: It is EPA's intent to implement these controls as a pan of the remedy as soon
as possible after issuance of the ROD.
Comment: EPA should explain what methods are considered for enhancing the breakdown of PAH hi
sediments. EPA should plan on a pilot study and implementation of these methods as an integral part
of the remedy, rather than as a contingency.
EPA Response: A preliminary listing of such methods is provided in the 1994 Proposed Plan and
the ROD, including harrowing and nutrient addition. EPA believes a ten-year timeframefbr
natural recovery in these areas is acceptable (provided institutional controls are implemented) and
likely to be effective. Before incorporating enhancement as a component of the remedy, EPA must
first assess whether such action is necessary to ensure recovery of the more contaminated
sediments and must select a suitable method for site conditions. If a suitable enhancement method
is necessary for certain areas and can be cost-effectively applied to a wider area, EPA may
determine that recovery of the wider area should be enhanced similarly.
Comment: More discussion of studies supporting faster PAH breakdown in intertidal areas is needed.
EPA Response: More detailed discussion is provided in Appendix D of the Feasibility Study (FS).
Comment: We support capping and natural recovery and would object to incineration, nearshore confined
disposal, and confined aquatic disposal
EPA Response: EPA's selected remedy reflects the same preferences.
Comment: The 1994 Proposed Plan appears to suggest that natural recovery could still be considered for
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subtidal areas. We believe that natural recovery should not be considered for cleanup of subtidal areas
after source control.
EPA Response: The 1994 Proposed Plan dearly indicates that after source control further
natural recovery will not be considered in subtidal areas. The Proposed Plan also notes that the
processes leading to sediment natural recovery are continuous. Any changes in areas of
contamination as a result of these ongoing processes will be reflected when final cleanup areas
are delineated after control of significant sources. As described in the selected remedy, subtidal
cleanup will be required for areas delineated at the time of source control. The only exception
to this is consideration of limited sediment recovery zones where warranted due to habitat value
or technical practicability.
Comment: EPA should carefully consider the impacts of a thick cap (greater than 1 foot in thickness)
on navigational access and commerce in the Harbor.
EPA Response: EPA intends to consider these impacts and to minimize them. EPA will
coordinate with the appropriate agencies, including DNR, the Gty ofBainbridge Island, and the
Washington State Ferries, in designing a final cap that is both environmentally protective and
compatible with harbor uses.
Comment: EPA has not balanced cost effectiveness with other decision criteria when it excluded natural
recovery as an option for the subtidal sediments. CERCLA and the State of Washington Sediment
Management Standards (Sediment Standards) require EPA to balance and weigh cost effectiveness of the
remedy with other considerations. The 1994 Proposed Plan notes that natural recovery may be
significantly more cost effective than capping.
<.
EPA Response: EPA considered cost-effectiveness, as required. The Proposed Plan notes that
natural recovery may cost less than active remediation. This is not a determination of cost-
effectiveness. EPA weighed the alternatives using the nine CERCLA criteria, which encompass
the three criteria in the Sediment Standards of cost, net environmental benefits, and technical
feasibility. EPA determined that the incremental cost of cleanup for subtidal sediments which
could recover within ten years of source control was justified by the extended timeframe prior to
source control. Final cleanup will likely be delayed several years beyond cleanup in the West
Harbor while source control efforts continue, and an additional ten years of potential significant
biological effects in natural recovery zones after control of sources was not warranted by the
potential cost savings. As noted in Section 11, the conditions for consideration of natural
recovery are more explicit in the selected remedy than in the Proposed Plan. Sensitive habitat
and technical feasibility are conditions which may alter the balance of cost, feasibility, and net
environmental benefits of cleanup. For areas with eelgrass or steep slopes, sediment recovery
zones may be designated, provided reasonable modifications to the remedy cannot be used to
address these areas actively.
Comment: EPA should defer plans and action on the removal of dock or piling structures until future
land use at the facility has been resolved. Some future use alternatives involve docks and piling
structures, and would benefit from using existing structures rather than having to build new ones. Such
uses would also save the cost of demolition.
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EPA Response: The basis for the decision to demolish these structures is more clearly articulated
in the selected remedy. EPA agrees that deferral of the decision may be appropriate. At this
time, the docks are not interfering with remedial actions in Eagle Harbor, nor are they
deteriorated to the point of posing human health risks. Deferral will allow additional time to
evaluate the need to use the in-water structures for implementing Wyckqff Facility cleanup actions
as well as for future uses of the property. This change to the proposed plan is identified in
Section 11 of the ROD.
Comment: We believe the creosoted docks, piers, and pilings at Wyckoff should be demolished to
remove them as a source of PAH releases.
EPA Response: EPA expects that removal of the pilings may ultimately be necessary to prevent
deteriorating structures from posing physical risks, interfering with sediment capping, and
releasing wood-treatment chemicals over time. If the structures are in good condition, are
useable, and are not interfering with site cleanup, they may be left standing. Relative to other
sources of PAHs, the impact of pilings may be localized. If retained for future uses, EPA
anticipates that over time, as the structural integrity of the wooden structures decreases,
maintenance of the structure will involve replacement of pilings with other materials, as is being
done at the Washington State Ferries terminal.
Comment: During remedial design, EPA should evaluate the potential impacts of subtidal capping on
eelgrass beds and on currents and flushing rates of the harbor. The cap should be designed to prevent
such impacts.
EPA Response.- EPA agrees that potential impacts on eelgrass should be eyaluated prior to
implementation of active sediment cleanup, and that impacts to functioning eelgrass habitat should
be avoided, through modifications to the remedy or designation of such areas as sediment
recovery zones. Regarding currents and flushing rates, the maximum volume of material which
could be used to cap existing problem areas is within 1 - 3 percent of the low-tide water volume
in the main basin. A slight increase of the exchange coefficient (an index of flushing) may occur,
with an associated increase in the flushing rates, generally a favorable outcome. Any
corresponding water quality changes would probably not be measurable. As a general rule,
increasing the exchange coefficient is desirable from a water quality standpoint.
Comment: DNR appreciates EPA's recognition that eelgrass beds require special consideration when
designing and conducting remedial activities. We agree with EPA that these areas are difficult to replace
if destroyed by remediation measures such as capping. We also agree that natural recovery with
monitoring is a viable alternative for the remediation of eelgrass beds. In addition, eelgrass beds may
qualify for an extension of the 10-year natural recovery period.
EPA Response: During remedial design, EPA will consider potential impacts to eelgrass beds
from cleanup in areas near eelgrass beds and will also consider whether cleanup is appropriate
in contaminated eelgrass beds. If evaluation of the eelgrass beds indicates that sediment
contamination is significantly decreasing the value of the beds as habitat and if natural recovery
in ten years is unlikely, appropriate decisions as to extending the recovery period or taking active
measures will be made at that time.
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3. Implementation Issues
Comment: EPA should provide information in the ROD about the monitoring schedule, methods, and
decision criteria to be used in evaluating the status of source control and in evaluating the existing cap.
EPA Response: In the ROD, EPA has added details on these subjects. However, much
refinement occurs in the remedial design stage or in documents separate from the ROD.
Moreover, while general guidelines regarding decision-making with respect to source control can
be developed at this stage, definitive technical criteria may not be appropriate, because of the
complexity of the issue. Determinations regarding the status of source control will rely at least
in part on professional judgment based on the combined information from inspections and site
monitoring data. However, monitoring data and EPA evaluations of the status of source control
will be documented in annual reports available for public review.
Comment: EPA should clearly state when the cleanup areas will be defined.
EPA Response: Cleanup areas will ultimately be defined during final remedial design, when
sources have been sufficiently controlled. Although planned and ongoing efforts are expected to
funher control sources, a specific time when source control will be sufficient to proceed with
design plans cannot be determined in advance, based on existing information; however, planning
documents for defining cleanup areas may be developed as significant sources are becoming
further reduced. Agencies and other interested parties will have an opportunity to review draft
plans as appropriate. It may take a year to two years to complete both the delineation of areas
and the design of the cleanup.
Comment: Prior to conducting additional investigations, EPA should undertake a single, comprehensive
effort to evaluate all past data quality issues in order to avoid any mistakes or methodologies that may
create uncertainty in any future data evaluation efforts.
EPA Response: Throughout the Remedial Investigation and Feasibility Study (RI/FS), EPA has
considered data quality and has evaluated any data quality problems which arose. While no
comprehensive evaluation of historical data is considered necessary, EPA is committed to the
development of high quality data and intends to continue to follow guidance, to involve qualified
reviewers, and to apply the appropriate methods for remedial design and monitoring data
collection.
Comment: High Pressure Liquid Chromatography (HPLC), a method of chemical analysis, may be
appropriate for use as a screening tool, but should not be used for setting boundaries of cleanup areas that
approach chemical cleanup standards listed in Ecology's Sediment Standards.
EPA Response: EPA agrees that compliance with cleanup standards may not be best assessed
using HPLC only, but will consider its use as a screening tool or in combination with other
methods.
Comment: Ecology's Sediment Management Unit (SMU) should be consulted on any proposed sampling
methodologies for chemical and biological tests.
EPA Response: Throughout the RI/FS, EPA has involved Ecology, including the SMU, in
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document reviews and planning, through state cooperative agreements funded by EPA. EPA will
continue to involve Ecology, through reviews of planning documents, reports, and design
documents as appropriate.
Comment: To overcome limitations on future uses of state aquatic lands, the ROD should be flexible
enough to allow parties to propose removal of contaminants from the navigation channel if a public need
arises.
EPA Response: Dredging near remediated areas of Eagle Harbor will not be ruled out entirely.
However, in reviewing permit requests, EPA and other agencies may impose additional sampling,
health and safety, environmental protection, and waste management requirements to ensure the
protection of human health and the environment, including ensuring that the effectiveness of
completed remediation is not affected. Similarly, for dredging in areas of remediation, such
requirements would be covered under CERCLA agreements.
Comment: The cleanup action should allow state aquatic lands to continue to fulfill public trust purposes
and not preclude future water-dependent uses, public access and utilization of renewable resources.
EPA Response: EPA recognizes DNR's responsibility to protect water-dependent uses, public
access, and utilization of renewable resources. EPA is responsible for protection of human health
and the environment. At this time, no conflict between the missions of these agencies is foreseen.
4, Other Issues
Comment: EPA has chosen to name DNR as a potentially responsible party for the cleanup of Eagle
Harbor; DNR believes it is not an "owner/operator" for purposes of CERCLA liability. DNR has
determined that it can authorize use of state resources for Superfund cleanup efforts under a mutually
acceptable settlement agreement with EPA. DNR has the statutory authority to authorize or deny use of
state-owned aquatic resources. Use of sediments from the Snohomish River or any other state-owned
aquatic lands for Eagle Harbor capping may be viewed as beneficial to the public trust if it resolves
alleged liabilities under CERCLA and provides for contribution protection.
EPA Response: Comments regarding determinations of CERCLA liability or settlement proposals
are not germane to the selection of the remedy and are therefore not addressed in this'
Responsiveness Summary.
Comment: EPA needs to further assess the impacts of the interim capping action on sediment quality in
areas east of the cap. Samples should be collected from previously sampled stations to determine if
contamination levels have increased. Sediment trap data collected during the interim action should be
used to determine contaminant loading resulting from displacement of sediments in the hotspot during
capping. The analysis should identify areas that now exceed MCULs for PAHs or no longer have the
potential to recover within 10 years of source control.
EPA Response: EPA has evaluated the impacts of releases that may have been associated with
completion of the existing cap in the East Harbor. This information is presented in the On-Scene
Coordinator's Report regarding the completed cap (EPA, 1994). The analysis indicates that
contaminant loading which occurred during the placement of the cap consisted primarily of low
molecular weight PAHs (LPAHs), which are readily degraded in the marine environment. Even
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if the depth of sediment in the traps reflects the thickness of sediment deposited on the bottom,
one of several conservative assumptions in the analysis, mixing of the new deposits into existing
surface sediments is likely to change surface concentrations only slightly. EPA expects that the
recent releases will not have an appreciable effect on the cleanup areas to be delineated after
significant contaminant sources are controlled. Conversely, the placement of clean dredged
material in over 50 acres has probably contributed to the recovery of contaminated areas
surrounding the cap.
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ATTACHMENT A
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RESPONSIVENESS SUMMARY
TO
PUBLIC COMMENTS
ON THE FEASIBILITY STUDY AND 1991 PROPOSED PLAN
FOR
EAGLE HARBOR
EAST HARBOR OPERABLE UNIT
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INTRODUCTION
The attached responsiveness summary is an appendix to the
June 15, 1993 Action Memorandum for the planned removal action in
the East Harbor Operable Unit (OU) of the Wyckoff/Eagle Harbor
Superfund Site. It is intended as a supplement to a
responsiveness summary issued on September 29, 1992 with the
Record of Decision (ROD) for the West Harbor Operable Unit (OU)
of the site. The 1992 responsiveness summary is incorporated by
reference into the attached responsiveness summary for the 1993
Action Memorandum. Both responsiveness summaries respond to
written and oral comments on the Eagle Harbor Remedial
Investigation and Feasibility Study (RI/FS) and the December 1991
Proposed Plan.
While the initial responsiveness summary addressed general
comments and comments specific to the West Harbor OU, the
attached responsiveness summary responds to questions and
comments relevant to the planned East Harbor OU Removal Action.
Comments addressed in both documents include a reference to their
section number in the 1992 responsiveness summary.
For your convenience, the table of contents for the 1992
responsiveness summary is provided below. The text of the 1992
responsiveness summary is in Appendix C of the West Harbor OU ROD
and can be reviewed at the Kitsap Regional Library in the City of
Bainbridge Island or at EPA Region 10 Headquarters in Seattle.
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1992 RESPONSIVENESS SUMMARY
Contents
Introduction
1.1. Overview
1.2. Structure
1.3. Scope of Response to Comments
Community Involvement
2.1. Background
2.2. Concerns Expressed During the Investigation Phase
2.3. The Public Comment Period
2.4. Future Community Involvement
Response to Comments Received During the Public Comment Period
3.1. Program Issues
3.1.1. Superfund Process
3.1.2. Cost and/or Quality of Studies
3.1.3. Coordination with other Agencies/Programs
3.1.4. Applicable or Relevant and Appropriate Requirements
3.2. Human Health Risks
3.3. Environmental Risks
3.4. Source Control
3.4.1. Source Identification
3.4.2. Status of Wyckoff Cleanup
3.4.3. Potential Recontamination
3.5. Natural Recovery: Modeling and Estimates
3.6. Cleanup Alternatives and Areas
3.6.1. General and/or Harbor-wide Comments
3.6.2 West Harbor Mercury Hot Spot
3.6.2.1. General Comments
3.6.2.2. Protection of Public Health and the Environment
3.6.2.3. Feasibility & Permanence of Options
3.6.2.4. Removal and Disposal
3.6.2.5. Cost & Volume/Area Estimates
3.6.2.6. Cost Effectiveness
3.6.3. West Harbor Intertidal Areas
3.6.3.1. General Comments
3.6.3.2. Protection of Public Health and the Environment
3.6.3.3. Feasibility & Permanence of Options
3.6.3.4. Cost & Volume/Area Estimates
3.6.3.5. Cost Effectiveness
3.6.4. West Harbor Subtidal Area
3.6.4.1. General Comments
3.6.4.2. Protection of Public Health and the Environment
3.6.4.3. Feasibility & Permanence of Options
3.6.4.4. Cost & Volume/Area Estimates
3.6.4.5. Cost Effectiveness
3.6.5. East Harbor Subtidal Area - Reserved [See East Harbor OU
responsiveness summary]
3.7. Remedial Design and Monitoring
3.7.1. General Comments
3.7.2. Timing of Remedial Action
3.7.3. Impacts on Navigation and Commerce
3.7.4. Baseline Monitoring
3.7.5. Source Monitoring
3.7.6. Sediment Sampling
3.7.7. Post Remedial Monitoring
Remaining Issues
4.1. Bacterial Contamination in Seafood
Appendices
5.1. References
5.2. List of Commenters
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Responsiveness summary
Wyckoff/Eagle Harbor Superfund Site
EAST HARBOR OPERABLE UNIT
3.6.5.1
(ROD Comment Number 3.6.4.2.3): Capping is inappropriate
because of the high cost and documented ecological damage
associated with capping large aquatic areas.
Response: Active remediation of any large area of sediments
will have short-term ecological impacts. However, capping
is one of the least costly alternatives available for
managing contaminated sediments, and it provides a clean
substrate for benthic organisms to recolonize. Studies of
sediment caps show that benthic recolonization occurs fairly
readily. The larger the cap is, the greater the short-term
impacts are expected to be; however, a more extensive cap
will provide the greatest long-term environmental benefit
and will decrease ecological impacts due to contamination in
the East Harbor.
3.6.5.2
(ROD Comment Number 3.6.5.2.3): The alternatives should
consider the impacts of grain size on the type of ecological
communities that may develop. In evaluating capping materials
for use at the site, the ability for supporting benthic
organisms should be considered. The use of one size of substrate
throughout the harbor could result in a "mono culture" and limit
ecological diversity in restored habitats.
Response: EPA will evaluate available materials for
sediment placement. Sand and silty sand are likely to
provide the bulk of materials for sediment placement. In
order to keep clean sediments in place, it may be necessary
to place larger grained materials (gravel or rocks) as
"armoring" in some areas. However, the likelihood of a
monoculture is low, in part because the range of physical
environments in Eagle Harbor, such as currents and slopes,
dictate a variety of sediment physical characteristics in
different areas. For example, materials in the ferry
propeller scour zone are larger sized than in protected
areas, such as the head of the bay. Other features, such as
depth, nutrient availability, and light further distinguish
ecological habitats.
3.6.5.3
(ROD Comment Number 3.6.5.1.6): The remedial actions should be
designed and implemented in a manner that minimizes impacts on
navigation and other uses of aquatic lands.
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Response: Because the East Harbor removal action includes
sediment placement, some impact on users of aquatic lands
may occur. These impacts could include requirements or
limitations on maintenance dredging, installation of piers,
and maintenance of existing structures in the area of the
sediment placement. Reasonable efforts will be made to
minimize impacts on the users of aquatic lands. No
significant impact on navigation is expected.
3.6.5.4
(ROD Comment Number 3.6.5.2.6): Institutional protection (such
as deed restrictions) of any caps should be included so that the
caps are not subjected to future development, such as pile
driving and dredging.
Response: Some institutional controls are presently in
place, specifically the process of permit application,
review, and approval for such activities. The Corps of
Engineers coordinates with resource agencies and EPA on
evaluating such applications individually. It is likely
that additional requirements such as chemical and biological
.testing, turbidity controls, or other steps beyond those
ordinarily required will be imposed. In some areas, permits
may be denied if adverse impacts to the remedy are
anticipated. Deed restrictions are not anticipated as an
institutional control requirement for this action.
3.6.5.5
(ROD Comment Number 3.6.1.8): When Does EPA plan to address the
following concerns?
How will cap be designed to withstand erosive forces
generated by ferry propeller wash?
Will compression due to weight of overlying cap material
force PAH out along the edge of the cap?
Will geotextile material be used to prevent the cap from
subsiding into the underlying contaminated sediments?
Where will the cap material come from and what criteria will
be used to determine that the cap material is clean?
How will EPA evaluate dredge placement procedures?
Response: For the East Harbor Removal Action, the following
responses .apply:
The surface of the cap in areas affected by ferry propeller
wash may be eroded somewhat after placement. Exact
determinations of the nature and extent of the erosion isn't
possible to determine in advance, however, and EPA intends
to monitor the physical conditions of the cap during
placement to identify erosional areas. These areas may
require additional sediment placement and armoring, which
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could be addressed pursuant to a Record of Decision (ROD) as
necessary.
Similarly, the potential compression by the cap of the most
highly contaminated sediments will be monitored during and
after placement. The cap will extend beyond areas of
sediment containing free-phase PAHs in order to avoid
releases at the edge of these localized zones. Long-term
monitoring and maintenance pursuant to a ROD will provide
for monitoring and additional actions as needed.
A clay or geotextile layer will not be used due to the
difficulty of applying them in these areas and their
questionable utility. Some subsidence may occur initially
in areas of finer, less compacted sediments. If so, the
material will serve as a foundation for additional sediment
to provide a suitable layer of clean material, either during
this action or in subsequent placement. (A three to six
foot cap is generally considered sufficient to isolate
sediment contamination, and the biologically active zone in
Eagle Harbor is estimated at 10 cm.)
The material to be used for this Removal Action will be
obtained through routine navigation dredging in the
Snohomish River. The sediments were tested and found to
meet both the Puget Sound Dredge Disposal Authority (PSDDA)
criteria for open water disposal and the State of Washington
Sediment Management Standards sediment quality criteria.
Two placement methods are proposed in the East Harbor, and
~ the methods will be evaluated through initial placements at'
the PSDDA disposal site in Port Gardner to determine the
appropriate placement rates. In addition, after initial
placement of a portion of the sediments in the East Harbor,
physical monitoring will be used to evaluate and, as
necessary, modify the placement methods, rates, and
sequencing.
3.6.5.6
(ROD Comment Number 3.4.2.1): Commenters have expressed concern
that efforts to achieve source control at the former wood
treating facility have not been fully successful and that
separation of the harbor and facility into operable units has
created an artificial distinction. Cleanup of the harbor may be
premature, because a full understanding of the extent of on-going
contamination from the facility to the harbor is not known.
Ecology has indicated that a 50% chance of recontamination would
be unacceptable.
Response: It is difficult to quantify the impact of past
sources and the rate of current sources of contamination
from the Wyckoff Facility OU to the East Harbor OU.
However, direct spills and discharges to the harbor
associated with past wood-treating operations are believed
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to be the source of a substantial portion of the existing
sediment contamination in the East Harbor. With the
cessation of plant operations in 1988, such direct
discharges were controlled. Ongoing secondary sources such
as seepage of contaminated ground water and oily
contamination into the harbor have been significantly
reduced since 1988 and will continue to decline through
continued response actions, including extraction and
treatment of contaminated groundwater, extraction of
floating and sinking product, and the removal of sludges at
the Wyckoff Facility OU.
Ground water measurements indicate that the ground water
gradient has been reversed by the extraction system. Over
100 million gallons of contaminated groundwater have been
pumped and treated, and an estimated 32,000 gallons of
product have been recovered from the extraction wells. The
removal of over 2,000 tons of contaminated sludges and the
construction of some 300 feet of sheetpiling was completed
in 1992, and continued work in 1993 will result in the
excavation of over 9,000 tons of sludge from heavily
contaminated portions of the transfer pit.
Geophysical data collected in Eagle Harbor, combined with
information from wells and borings on land and in the
harbor, point to the existence of a hard clay layer which
tilts steeply away from the area to be capped in the East
Harbor Removal Action. Thus, most Dense Non-Aqueous-Phase /
Liquid (DNAPL) migrating from the facility is expected to
travel downward to this layer, then laterally along the top,
rather than emerging in surface sediments in Eagle Harbor.
EPA plans to conduct additional borings to verify the
existence of such a layer this September.
EPA recognizes that contaminant seepage on the eastern side
of the facility is still occurring. However, the importance
of this seepage to the East Harbor removal action areas
(west of the shoal and in the central channel) is believed
to be minimal. In the meantime, continued exposure of
marine life to the highly contaminated sediments in this
area cannot be justified. As extraction of groundwater
continues and additional response actions are completed at
the facility, seepage is expected to be further reduced.
Taking action in heavily contaminated subtidal areas of the
East Harbor before final cleanup actions at the facility
have been completed is therefore warranted, given the
minimal (and decreasing) impacts of ongoing sources on these
areas. Phasing cleanup and evaluating the outcome of the
first phase will provide further information regarding the
significance of continuing sources.
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3.6.5.7
(ROD Comment Number 3.7.2.3;: Since the Wyckoff operable unit
is not as far along in the RI/FS process, the potential exists
for contamination sources from the Wyckoff facility into the East
Harbor to continue. Cleanup of the harbor and the Wyckoff
facility should be coordinated.
Response: EPA is accelerating cleanup activities at the
Wyckoff OU. Since June 1992, EPA has been excavating buried
sludges at the Wyckoff OU for disposal off site, and the
ongoing extraction of oil and contaminated ground water by
the company has reduced groundwater releases and oily
seepage. EPA will continue to consider additional early
actions as appropriate, but believes control of sources to
the East Harbor is sufficient to justify efforts to address
the most contaminated sediments of the East Harbor. The
phased approach to site cleanup will allow EPA to evaluate
information developed during the Wyckoff OU RI/FS in
developing a final cleanup decision for the East Harbor OU.
EPA recognizes this and intends to maintain appropriate
coordination between the units.
3.6.5.8
(ROD Comment Number 3.7.2.2): EPA should incorporate flexibility
into the proposed plan and record of decision to allow
consideration of mechanisms for speeding up cleanup of the site.
Response: EPA would like cleanup of the site to proceed as
speedily as possible and therefore chose to move forward
with the East Harbor removal action. The groundwater
extraction on the Wyckoff OU and the sludge removal in 1992
and 1993 are examples of other early actions intended to
accelerate cleanup. EPA will continue to look for ways to
speed up cleanup by conducting or requiring early actions or
phased actions as appropriate.
3.6.5.5
(ROD Comment Number 3.7.7.3): Additional information on which
contaminants will be monitored, monitoring rationale, and
frequency is needed. Organisms, such as clams and fish
(including small food fish) should be monitored for exposure to
mercury and PAHs. Periodic verification of the structural
integrity (depth, contours, configuration, thickness, and
dimensions) of the caps is also recommended.
Response: Detailed information about the type and amount of
monitoring is generally developed subsequent to a ROD or
action memorandum. Plans are in development for monitoring
during and shortly after implementation of the East Harbor
Removal Action. Subsequent to the East Harbor ROD, plans
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will be modified to address any additional sampling and
monitoring needs. The plans will define monitoring
objectives and the necessary data to accomplish these
objectives.
3.6.5.10
(ROD Comment Number 3.7.4*3): In developing a plan for
additional testing to define sediment remedial areas, EPA should
consider the adequacy of previous data and should maintain
consistency with the Sediment Management Standards.
Response: EPA will consider these points when developing
plans for testing during remedial design and monitoring
after remediation.
3.6.5.11
(POD Comment Number 3.5.1): [NOTE: Comments on EPA's evaluation
of natural recovery were submitted by numerous commenters. EPA
has chosen to respond at length to the detailed comments provided
by the Washington State Department of Transportation (WSDOT), as
other comments tended to be more general. Included with the
letter of comment were the results of WSDOT's evaluation of
natural recovery. The results suggested that natural recovery
would occur in most subtidal areas of the West Harbor.]
Comment: EPA's assessment of natural recovery in the R^/FS should
not be relied on for the following reasons:
1. It did not consider direct measurements of sedimentation
(e.g., sediment trap data collected by WSDOT).
2. It relied on a watershed runoff model.
3. It neglected the importance of mixing and diffusion.
4. The procedures used were not consistent *rith procedures
recommended in the Sediment Standards.
5. It did not consider resuspension.
The results of the model used by WSDOT to predict natural
recovery in Eagle Harbor (Officer and Lynch, 1989) were provided
in a comment letter and attachments.
Response: EPA's response addresses the numbered items, then
provides comparisons between EPA's and WSDOT's natural
recovery analyses.
1. As direct measures of sedimentation, the sediment trap
data collected by WSDOT could indicate a gross
sedimentation rate for Eagle Harbor. However, results
from three traps in this shallow embayment with known
localized sources of artificially-induced resuspension
(e.g., ferry prop wash) are not considered accurate
enough to predict average or local sedimentation rates
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under the conditions that prevail in Eagle Harbor. The
WSDOT data are questionable for the following reasons:
a. The gross sedimentation rates proposed are higher
than rates observed in both Elliott Bay and
Commencement Bay (Patmont and Crecelius, 1991),
both embayments with substantially higher inputs
of sediment from large river systems than occurs
in Eagle Harbor.
b. Local variations in the effect of ferry prop wash
on rates of resuspension are likely to be extreme.
c. The sediment traps sample a group of particulates
that is not very representative of the bulk of the
suspended particulates in terms of physical
properties, because they consist primarily of
biologically aggregated particulates rather than
finely divided inorganic and organic particles.
EPA used the watershed runoff evaluation model along
with estimates of shoreline erosion to estimate the
magnitude of new sediment sources to Eagle Harbor. The
estimates of sedimentation rates were based on an
evaluation of the potential sources in comparison with
measured current speeds to determine what size and
amount of sediment might be accumulating in Eagle
Harbor (RI, Appendix B). The estimates of n^t
sedimentation rates and depth of mixed sediment in
Eagle Harbor proposed by Hart Crowser for WSDOT
(March 15, 1989) were evaluated in technical
memorandum 4 (EPA, December 5, 1989). It was concluded
that the lead-210 data could be used to assess
historical sedimentation rates, but did not adequately
measure mixing depth or present sedimentation rates.
Mixing and diffusion were considered in EPA's
assessment of natural recovery. In all of the models
suggested by WSDOT, mixing is represented as a
diffusion rate expressed throughout a sediment layer.
In EPA's evaluation, a simplifying assumption was made
that mixing with the biologically active zone was
complete in less than 1 year. The term diffusion has
also been applied to the process of advection of
sediment to the water column, and subsequent movement
out of Eagle Harbor. That process too was assessed,
based on rates discussed and accepted by the Technical
Discussion Group Natural Recovery Subgroup. WSDOT now
proposes a much larger advection term (about 25 times
larger). A more detailed evaluation of the specific
assumptions of the WSDOT model are discussed below in
response to Item 5, above.
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4. The procedures for evaluating natural recovery used by
EPA were simpler approximations of the procedures used
in three models used previously in Puget Sound: SEDCAM,
Core Mix, and WASP 4. They provided a relatively
inexpensive way to evaluate natural recovery and were
consistent in complexity with the input data that were
and are available. The results were reviewed and
accepted by the State Department of Ecology.
A significant risk of relying on any of the models
proposed (and used) by WSDOT is the underlying
assumption that exchange between the surface mixed
layer and the (often) more contaminated deep (i.e.
below 10 cm.) layers is zero. Some exchange between
the deeper sediment and the surface mixed layer is
likely, but cannot be quantified. Two mechanisms of
exchange, diffusion and upward flow of liquid
contaminants, are discussed in Appendix D-3 of the FS
with regard to PAH. Mercury does not occur as free
liquid, but organic mercury is very likely to be
associated with materials that are more diffusive than
the organic compounds discussed in the FS.
An alternative hypothesis to the model proposed by
WSDOT is that the concentrations in the mixed layer
represent a (short-term} equilibrium between upward
diffusion and mixing from the deep sediments and
balancing advection out of Eagle Harbor.
5. Resuspension was included in EPA's analysis of natural
recovery (presented in Appendix D-l of the FS). The
rates of resuspension and advection out of Eagle Harbor
were lower than those proposed by WSDOT in their
comments and in Attachment A to their comments of
February 25, 1992,
There are some inconsistencies between the assumed
conditions in the WSDOT analysis and available evidence from
Eagle Harbor. The WSDOT conditions (input variables) are
compared with EPA conditions below.
Net sediment accumulation (v):
0.001 gm/cm2-yr assumed by WSDOT. The EPA
analysis considered a range of 0.0027 to
0.018 gm/cm2-yr.
Advective exchange (V):
0.7 gm/cm2-yr used by WSDOT. The EPA analysis
used an equivalent, but much smaller, term of
0.021 mg/cm2-yr. WSDOT1 s value was based on the
sediment trap data discussed above, and a presumed
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(and reasonable) fraction of resuspended sediment
that might be washed out of Eagle Harbor. The
value of V assumed by WSDOT appears to exceed the
supply of suspended sediment passing through Eagle
Harbor (FS, Appendix D-l) . Note that if the
concentration of suspended solids in Eagle Harbor
is about 3 mg/1 (rather than the 1 mg/1 assumed by
EPA) and if all the particulates were advected out
of Eagle Harbor, a value of V=0.7 gm/cm2-yr would
be possible. With a 50 percent advection as
assumed by WSDOT, the particulate concentration in
Eagle Harbor would have to be about 6 mg/1, about
twice the highest value reported by Baker (1984)
for central Puget Sound.
Diffusion or mixing coefficient (D):
0.7 gm2/cm*-yr used by WSDOT. The EPA analysis
assumed a higher D, in excess of 1, so that mixing
in the upper 10 cm of sediment would be complete
in 1 year. D=0.7 gm/cm*-yr is reasonable and
supported by the literature. However, small
changes in this constant do not significantly
affect calculated concentrations after 10 years of
mixing.
Mass of sediment accumulated in the mixed depth (d) :
2.0 gm/cm2 used by WSDOT. The EPA analysis used
values of 5.4 to 7.4 gm/cm2 for this term, values '
characteristic of the upper 2 to 10 cm of sediment
in Eagle Harbor. The value used by WSDOT appears
to be based on a shallower assumed mixing depth
(4 cm) (Patmont and Crecelius, 1991) and a very
low porosity. This value is inconsistent with
values for other parts of Puget Sound (Romberg, et
al., 1984) and observed in Eagle Harbor (Hart-
Crowser, March 1989).
Changes in estimated half-lives of contaminants in
Eagle Harbor are roughly proportional to changes
in the value of d if all other model inputs remain
constant. Therefore, increasing d five-fold would
increase half lives approximately five-fold. With
an even deeper mixing zone of 15 to 20 cm, which
occurs in parts of western Eagle Harbor (Weston,
1990), values of d could approach or exceed
15 gm/cm2, and contaminant half-lives would be
even longer.
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5.6.5.12
(ROD Comment WumJber 3.4.3.3; Why isn't groundwater considered a
media of concern for Eagle Harbor?
Response: Groundwater is of concern as a pathway of
contaminants to sediments in the East Harbor operable unit
This source of contaminants can best be addressed by
response actions at the Wyckoff OU rather than the East
Harbor OU. To date EPA has focused its efforts at the
Wyckoff OU on control of groundwater and other sources of
contamination to the harbor. Since 1990, the extraction
system at the Wyckoff OU has reduced the amount of
groundwater and oily seepage released to the harbor. The
Wyckoff RI/FS now underway will provide information about
additional actions needed. During the RI/FS for Eagle
Harbor, a subsurface hydrology study was performed to
investigate groundwater movement to the East Harbor OU
sediments (Technical Memorandum 7, March 7, 1990). The
study indicated that groundwater enters the harbor primarily
through sediments north and east of the Wyckoff facility.
While not insignificant, transport of dissolved
contamination does not appear to be a major mechanism for
contamination of the sediments relative to past discharges
and spills. Including groundwater as a medium of concern
rather than a pathway of concern for the East Harbor OU
would not change the sampling approach, the risk assessment,
or alternatives for sediment remediation. However, as a
~ source, groundwater is being addressed (see also 3.6.5.6).
5.6.5.13
Comment: Data from the deep sediment sampling conducted in
November 1989 indicate that contamination in the central harbor
area may extend as far as 6 meters below the surface. Table 2-4
shows that a depth of only 1 meter was used to determine the
volume of sediment requiring remediation. This could
significantly affect the cost estimates for treatment and
disposal of these sediments presented in Chapter 6.
Response: It is acknowledged that there is sediment
contamination found in parts of the central harbor area to
depths greater than 1 meter. However, the data indicate
that contamination in much of the harbor is limited to the
upper 0.5 meters. A 1-meter depth of remediation was
assumed as a conservative average for calculating material
volumes and costs for remediation in the PAH areas.
Comment 5.6.5.14
(ROD Comment Number 3.6.1.7): Were costs to pre-densify
sediments to prevent the cap from subsiding intp the underlying
sediments included in the cost estimates?
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Response: No predensification is planned for the East
Harbor removal action. EPA's feasibility study, including
the cost estimates, assumed that sediments would not be pre-
densif ied. Predensification could potentially release free
creosote product into the water column.
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