PB96-963123
EPA/AMD/R10-96/148
March 1997
EPA Superfund
Record of Decision Amendment:
Harbor Island (Lead),
Seattle, WA
1/25/1996
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UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
REGION 10
1200 SIXTH AVENUE
SEATTLE, WASHINGTON
AMENDED RECORD OF DECISION,
DECISION SUMMARY
THE REVISED REMEDIAL ACTION FOR THE
. SOIL AND GROUNDWATER OPERABLE UNIT OF THE
HARBOR ISLAND SUPERFUND SITE IN SEATTLE, WASHINGTON
JANUARY 1996
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Declaration for the
Soil and Groundwater Operable Unit of the Harbor Island
Superfund Site
Amended Record of Decision
Site
Soil and Groundwater 'Operable Unit, Harbor Island Site
Seattle, King County, Washington
Statement of Basis and Purpose
This amendment to the Record of Decision (Amended ROD) has
been developed in .accordance with the Comprehensive Environmental
Response, Compensation and Liability Act of 1980 (CERCLA), as
amended, 42 U.S.C. Section 9601 et seq. , and to the extent
practicable, the National Oil and Hazardous Substances Pollution
Contingency Plan (NCP), 40 C.F.R. Part 300. This decision is
based on the Administrative Record for this site, updated August
24, 1995, to include new information generated since the original
ROD. The documents which have been added to the Administrative
Record, upon which the modification is based, are provided in
attachment A. ' • .
This decision document modifies the remedial action for
treating petroleum contaminated soil at the Soil and Groundwater
Operable Unit of the Harbor Island Site (Site) in Seattle,
Washington. The ROD for this operable unit, signed on September
30, 1993, required thermal desorption treatment for"hot-spot soil
with total petroleum hydrocarbon (TPH) concentrations exceeding
10,000 mg/kg. This soil is not considered to be a Resource
Conservation and Recovery Act (RCRA) waste because it contains no
contaminants at levels of concern other than petroleum, which is
exempted under RCRA. However, petroleum i-s a dangerous waste
under the State of Washington's Dangerous Waste Regulations. The
purpose of this Record of Decision amendment is to allow TPH hot-
spot soil, which can be classified as non-dangerous waste, to be
disposed at the Roosevelt Regional Landfill in Klickitat County,
Washington, or an equivalent landfill. After excavation, soil
will be analyzed to determine if it is non-dangerous or dangerous
waste. Soil which is determined to be non-dangerous according to
these analyses will be disposed at an off-site landfill. Soil
which is dangerous waste will be treated by thermal desorption as
specified in the original remedy.
The State of Washington concurs with the selection of the
modified remedy described in this document. EPA's Office of Solid
Waste and Emergency Response was also consulted prior to the .
selection of the modified remedy.
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Assessment of the Site
. Actual or threatened releases of hazardous substances from
this site, if not addressed by implementing the remaining
components of the selected remedy, FS documented in the original
ROD, rr.ay present an imminent and substantial threat to human
health, welfare, or the environment.
Declaration
Although this Amended ROD modifies .the -original remedy
selected in the ROD, the modified remedy is considered to be
protective of human health and the environment. Implementation of
the remaining components of the selected remedy still comply with
federal and state applicable or relevant and appropriate
requirements, are cost effective, and utilize treatment to the
maximum extent practicable.
The proposed changes to the remedy do not negate the need
for a five year review. Hazardous substances will remain on the
site within the ground water above health-based levels,
therefore, 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.
CLARKE dat
Regional Administrator, Region 10
U.S. Environmental Protection Agency
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SOIL AND GROUNDWATER OPERABLE UNIT, HARBOR ISLAND
SUPERFUND SITE
AMENDED RECORD OF DECISION
DECISION SUMMARY
TABLE OF CONTENTS
Page
INTRODUCTION 1
SITE HISTORY . 2
REMEDY SELECTED IN THE ROD 4
REASONS FOR ISSUING AMENDED ROD. 5.
DESCRIPTION OF THE MODIFIED REMEDY 6
EVALUATION OF ALTERNATIVES 7
STATUTORY DETERMINATIONS 9
ATTACHMENTS
Attachment A - THE PROPOSAL TO MODIFY THE SELECTED REMEDY
LIST OF FIGURES
Figure 1 - Harbor Island Location Map
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SOIL AND GROUNDWATER OPERABLE UNIT, HARBOR ISLAND
SUPERFUND SITE
AMENDED RECORD OF DECISION
DECISION SUMMARY
INTRODUCTION
Site Name and Location
Harbor Island, Soil and Groundwater Operable Unit,
Seattle, Washington
Lead and Support Agencies
The U.S. Environmental Protection Agency (EPA) is the lead
agency and the Washington State Department of Ecology (Ecology)
is the support agency for this Site.
Statutory Citation for a ROD Amendment
In Section 117(c) of CERCLA, provisions are made for
addressing and documenting changes to the selected remedy that
occur after the Record of Decision (ROD) is signed. '. This Amended
ROD documents the changes to the selected remedy in accordance
with CERCLA Section 117. Additionally, since fundamental changes
are being made to the original remedy, public participation and
documentation procedures specified in NCP section
300.435 (c) (2) (ii) have been followed.
Date of ROD Signature
The ROD for the Harbor Island Soil and Groundwater operable
unit was signed on September 30, 1993.
Need for a ROD Amendment
Forty Potentially Responsible Parties (PRPs) signed the
Consent Decree to perform the remedy selected in the ROD. In
March 1995, as EPA was preparing to lodge the Consent Decree for
this operable unit, the PRPs submitted a proposal, in the form of
two letters dated March 24, 1995, and April 11, 1995 (see
attachment A). This proposal requested that EPA allow TPH hot-
spot soil, which is determined to be non-dangerous waste, to be
disposed at the Roosevelt Regional Landfill located in Klickitat
County, Washington. This soil is not considered to be a Resource
Conservation and Recovery Act (RCRA) waste because it contains no
contaminants at levels of concern other than petroleum, which is
exempted under RCRA. However, petroleum is considered to be a
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dangerous waste under the State of Washington's Dangerous Waste
Regulations.
The proposal provided new information on the cost and
ti:r,e frame for off-Site disposal of TPH hot-spot soil. The
proposal concluded that off-Site disposal would reduce cost and
allow completion of the remedy in a shorter timeframe than the
remedy selected in the ROD. After reviewing the proposal, EPA
agreed that the modified remedy had the potential to save
significant cost and time, and decided that a ROD amendment was
appropriate. The Consent Decree, with a copy of the proposed ROD
amendment attached, was lodged in Federal District Court for the
Western District of Washington, Seattle Division,, on October 6,
1995.
Administrative Record
This ROD amendment will become part of the Administrative
Record for the Harbor Island Superfund Site, as required by
Section 300.825(a)(2) of the NCP, and will be available to the
public at the following location:
U.S. Environmental. Protection Agency
Record Center, 7th Floor
1200 Sixth Avenue
Seattle, Washington 98101
SITE HISTORY
Harbor Island is located approximately one mile southwest of
downtown Seattle, in King County, Washington, and lies at the
mouth of the Duwamish River on the southern edge of Elliott Bay.
The island is approximately 400 acres in size and is bordered by
the east and west waterways of the Duwamish River (see Figure 1) .
From 1903 to 1905, Harbor Island was created from marine '
sediments dredged from the Duwamish River. Dredged sediment was
placed across the Duwamish tidelands to form a generally
homogeneous sandy fill which is now Harbor Island. Since
construction, Harbor Island has been used for commercial and
industrial activities including shipping, railroad
transportation, bulk petroleum storage and transfer, secondary
jLead smelting, lead fabrication, shipbuilding, and metal plating.
Warehouses, laboratories, and office buildings have also been
located on the island. Harbor Island was placed on the National
Priorities List as a Superfund Site in 1983 due to elevated lead
concentrations in soil from the former lead smelter on the
island, (which ceased operation in 1984) as well as elevated
levels of other hazardous substances identified at the Site.
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Seattle
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Washington State
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Figure 1
Harbor Island Location
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EPA has divided the Site into five operable units: 1) the
petroleum storage tank facilities operable unit, 2) the marine
sediment operable unit, 3) the shipyard sediment operable unit,
4) the Lockheed Shipyard facility operable unit, and 5) the "soil
and groundwater" operable unit which covers the rest of the
island. EPA is the lead agency for the. Lockheed, marine
sediments, shipyard sediments, and soil and groundwater operable
units. The ROD for the Lockheed Shipyard facility was signed on
June 28, 1994. A Consent Decree committing Lockheed to perform
the necessary remedial actions for this operable unit was entered
in February, 1995. EPA has designated Ecology as the lead agency
for the petroleum storage tank operable unit because the primary
contaminant there is petroleum, which is-excluded from CERCLA but
is a hazardous substance under the State's Model Toxic Control
Act (MTCA). Ecology intends to issue a Cleanup Action Plan for
the petroleum storage tank unit in 1996.
EPA completed a Phase I Remedial Investigation of Harbor
Island in 1990. EPA initiated a Phase II investigation in May,
1991, and completed the Remedial Investigation and Feasibility
Study reports for the Soil and Groundwater operable unit in
February, 1993. The results of the Remedial Investigation are
summarized below.
The most significant inorganic contaminant in the soil is
lead, which is found over most of the island and originated
primarily from the lead smelter. The majority of samples with
elevated lead in the range from 5,000 to 200,000 mg/kg, occurred
in surface soil in the central portion of the site. The highest
concentrations of other inorganics were also found in surface
soil and include: arsenic at 1,830 mg/kg, cadmium at 131 mg/kg,
and chromium at 791 mg/kg.
The most significant organic contaminant found in subsurface
soil was petroleum. The range of petroleum concentrations were
between approximately 20 mg/kg and 51,000 mg/kg. Soil with Total
Petroleum Hydrocarbon (TPH) concentrations exceeding 10,000 mg/kg
were identified as TPH "hot spots". Because most of the TPH hot
spot soil is in the subsurface, concentrations of inorganics in
the TPH hot spots are much lower than found in surface soil and
range from background to about 300 mg/kg. Also present in smaller
quantities in surface soil were polycyclic aromatic hydrocarbons
(PAHs) and polychlorinated biphenyls (PCBs). The highest
concentrations of PAHs found in surface soil ranged between 10
and 50 mg/kg. PCBs in surface soil ranged from 2 to 420 mg/kg.
Floating petroleum product was found at one location
adjacent to the shoreline on the north end of the island.
Groundwater at several locations along the shoreline on the
northern portion of the island also contained benzene,
ethylbenzene, and xylene, vinyl chloride, and other compounds
associated with petroleum products. Elevated levels of inorganic
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contaminants including mercury, nickel, cadmium, lead, and zinc
are also found in groundwater across the island.
On June 23, 1993, issued a Proposed Plan for the soil and
groundwater operable unit. The ROD for this unit was signed on
September 30, 1993. An Explanation of Significant Difference
(ESD) for this ROD was signed on July 26, 1994. The ESD modified
the selected thermal desorption' treatment technology to include
an afterburner.
A detailed description of Site characteristics, nature and
extent of contamination, human health risks, and Remedial Action
Objectives can be found in the ROD for this operable unit.
REMEDY SELECTED IN THE ROD
The remedy selected in the ROD for the soil and groundwater
operable unit, as modified by the ESD, includes the following
components:
• . Excavate and treat or dispose soil hot spots which
contain the highest concentrations of contamination.
These soil hot spots are defined as Total Petroleum
Hydrocarbons (TPH) greater than 10,000 mg/kg, PCBs
greater than 50 mg/kg, and soil with mixed carcinogens
with a total risk greater than 10"4. TPH hot spot soil
will be treated 6n-Site by a thermal desorption system
with an afterburner. PCB and mixed-carcinogen hot spot
soil will be disposed in an off-Site hazardous waste
disposal facility.
• Contain exposed contaminated soil exceeding inorganic
or organic cleanup goals. Containment will be achieved
with a three inch asphalt cap which would prevent
infiltration of rainwater and reduce contaminant
migration into the environment. Existing asphalt and,
concrete surfaces will be repaired to prevent
infiltration of rainwater.
• Remove and treat floating petroleum product arid
associated contaminated groundwater at Todd Shipyards
to prevent its migration into the marine environment.
Monitor groundwater quality for 30 years and review
groundwater quality data every 5 years to assess the
effectiveness of the selected remedy.
• Invoke institutional controls which would require long
term maintenance of new and existing caps, warn future
property owners of remaining contamination contained
under capped areas on their properties, and specify
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procedures for handling and disposal of excavated
contaminated soil from beneath the capped areas if
future excavation is necessary.
The remedial action selected for the soil and groundwater
operable unit addresses all contaminated soil and groundwater
exclusive of the petroleum tank farms and the Lockheed Shipyard,
which are separate operable units. The remedy selected for the
Lockheed operable unit is consistent with the remedy for this
unit .
Contaminated media at Harbor Island consists of soil,
groundwater and sediments. The overall remedial strategy for
Harbor Island is to initiate clean up of contaminated soil and
groundwater first because they pose a risk to human health and
act as sources of contamination to the marine sediments. The need
for cleanup of sediments will be the subject of future RODs.
Actions necessary to address the tank farms will be identified by
Ecology in a state ROD. Cleanup of the sediments, if necessary,
will occur after control of on-Site contaminant sources has been
initiated.
REASONS FOR ISSUING AMENDED ROD
The proposed modification to the remedy would allow TPH hot
spot soil, which is non-dangerous waste, to be disposed off-Site
in a solid waste landfill instead of being treated on-Site "by
thermal desorption. Off-Site disposal of contaminated soil at a
hazardous waste landfill had been considered as an alternative
for the soil and groundwater unit, but was not selected as the
remedy because it is significantly more expensive than other
alternatives which were considered. However, TPH hot spot soil
which is non-dangerous waste, as determined by appropriate tests,
could be disposed at a permitted solid waste facility. According
to the proposal submitted by the PRPs, disposal at a solid waste
facility would cost less and could be conducted in a shorter.
timeframe than on-Site thermal desorption.
According to the-PRPs' proposal, the estimated overall
savings of disposing TPH hot spot soil at a solid waste facility,
instead of treating it by thermal desorption, is about $6
Million. Disposal at a solid waste facility could also be
conducted in a shorter timeframe because the contaminated soil
could be shipped off-Site by rail at a faster rate than it could
be treated by thermal desorption. According to the PRPs'
proposal, this modified remedy can be completed in 5 months,
compared to about 16 months to complete on-Site thermal
desorption according to EPA's current estimate. This amounts to a
potential time savings of approximately 11 months.
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Based on the potential cost and time savings identified
above, EPA has determined that it is appropriate to modify the
selected remedy. Due to the fundamental nature of the remedy
modification, it was further determined that a ROD amendment was
necessary to document this decision.
DESCRIPTION OF THE MODIFIED REMEDY
This amendment modifies only the thermal desorption
treatment portion of the remedy selected in the ROD. The modified
remedy will allow TPH hot spot soil, which is non-dangerous
waste, to be disposed of at the Roosevelt Regional Landfill or an
equivalent upon prior written approval by EPA. TPH hot spot soil,
which is non-da-ngerous waste, may nevertheless be treated by
thermal desorption if a good reason for doing so, such as a
significant savings of time or money, is advanced by the PRPs.
Treatment by thermal desorption of non-dangerous waste which
would be accepted by Roosevelt Regional Landfill shall require
prior written approval from the EPA Remedial Project Manager.
To identify soil which exceeds the hot spot criteria and
requires excavation, a gas chromatography field analytical method
WTPK-HCID (detection limit 100 mg/kg), will be used to determine
total in-situ TPH concentrations prior to excavation. Soil will
be analyzed for TPH at a minimum frequency of about one sample
per 100 cubic yards of soil or whenever visual inspection
indicates a change in TPH concentration.. To determine when the
boundary of the TPH hot spots is reached and when excavation will
cease, confirmatory analysis of soil samples will be required by
method WTPH-HCID (detection limit 50 mg/kg} at an off-Site
laboratory approved by EPA under the Contract Laboratory Program.
To determine which TPH hot spot soil is non-dangerous waste,
soil will be tested according to the methods specified in,
"Analytical Requirements for Petroleum Contaminated Soil Disposal
at Roosevelt Regional Landfill, Klickitat County, Washington.". .
The required analyses will be as follows.- Soil with in-situ TPH
concentrations between 10,000 and 30,000 mg/kg will be excavated
and placed in a separate stockpile. Representative samples of
this stockpile will be analyzed for: 1) TPH concentration
according to methods WTPH-G, WTPH-D, or,WTPH-418.1 modified
(depending on the results of the in-situ analyses), 2) leachable
metals according to EPA's TCLP method, 3) volatile organic
compounds according to EPA method 8240, and 4) semi-volatile
organic compounds according to EPA method 8270.
Soil with in-situ TPH concentrations exceeding 30,000 mg/kg
will be segregated into individual stockpiles, each of which
contain TPH concentrations covering a range of about 10,000
mg/kg. This will result in individual stockpiles for
concentration ranges of 30,000-40,000 mg/kg, 40,000-50,000 mg/kg,
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50,000-60,000 mg/kg, etc, respectively. Representative samples of
each of these stockpiles will first be analyzed by the methods
specified above. If soil is determined to be non-dangerous waste
according to this first tier of tests, it will then be tested by
the fish bioassay method identified in WAC 173-303-101(5).
Soil which is non-dangerous waste according to the above
tests will be shipped by rail in closeable containers to the
Roosevelt Regional Landfill for disposal. Soil which is dangerous
waste according to any of the above test will be treated by
thermal desorption as specified in the original remedy.
In order to operate the thermal desorption systems under
optimal conditions, soil fed into the system cannot contain TPH
concentrations exceeding approximately 30,000 mg/kg. To achieve
this objective, any soil which must be treated and which exceeds
a TPH concentration of 30,000 mg/kg should be blended with clean
soil or soil with TPH concentrations less than 30,000 mg/kg prior
to treatment.
EVALUATION OF ALTERNATIVES
The NCP establishes nine criteria for evaluating remedial
action alternatives. Under SARA Section 121, a profile of the
original selected remedy and the modified remedy against the nine
criteria is required. In this section, the treatment portion of
the remedy selected in. the ROD will be compared to the modified
remedy based on the nine evaluation criteria.
Overall Protection of Human Health and the Environment
Both the original and modified remedies are considered to be
protective of human health and the environment. The original
remedy meets this criteria by requiring thermal destruction of
TPH contamination exceeding concentrations of 10,000 mg/kg. The
modified remedy allows non-dangerous waste TPH hot spot soiX to
be disposed off-Site. This modification to the remedy is also
protective because it will prevent migration of contaminants and
potential exposure to these contaminants through confinement.
Confinement is assured because the selected landfill has an
impermeable liner with a leachate collection system overlying a
two-foot thick layer of recompacted clay soil. In addition, this
landfill is isolated .from the regional aquifer by 300 feet of
naturally-occurring clay soil.
Compliance With ARARs
Both alternatives comply with all ARARs. The portion of the
remedy which will be modified addresses only TPH contaminated
soil which is neither a hazardous substance under CERCLA, nor a
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dangerous waste under the Washington State Dangerous Waste
Regulations.
Long-Term Effectiveness and Permanence
, Both the original and modified remedies are considered to
have comparable long-term effectiveness and permanence. The-
original remedy achieves permanence by thermal destruction of TPH
contamination. The modified remedy achieves permanence through a
combination of confinement of non-dangerous waste TPH hot spot
soil in an off-Site landfill, and thermal destruction of TPK
contamination in soil which is determined to be dangerous waste.
The long-term confinement of TPH contamination in the Roosevelt
landfill is assured by two factors: 1) a state-of-the-art design
which includes an impermeable liner with a leachate collection
system overlying a two-foot thick layer of recompacted clay soil,
and 2) a location in a remote, arid area where migration of
contaminants to the regional aquifer is prevented by 300 feet of
naturally-occurring clay soil.
Reduction of Toxicity, Mobility, and Volume Through Treatment
The original remedy specifies treatment of all TPH hot spot
soil, which amounts to a volume of approximately 90,000 cubic
yards of soil. The modified remedy will require treatment of
significantly less soil because, based on experience, the
operator of the Roosevelt Regional Landfill expects most, if not
all, of the soil with TPH concentration below 30,000 mg/kg to be
non7-dangerous waste and acceptable to the landfill. Current data
indicates that a majority of the hot spot soil has TPH
concentrations below 30,000 mg/kg.
Although treatment remains an integral component of the
modified remedy, the original remedy better meets this criteria
since it guarantees treatment of a greater volume of soil, thus
providing a greater overall reduction in toxicity, mobility, and
volume. '.
Short Term Effectiveness
EPA estimates that the timeframe to implement soil treatment
component of the original remedy would be about 16 months. This
duration of time is required because of the limited rate at which
TPH contaminated soil can be treated by a thermal desorption
system. The PRPs' proposal estimates that is will take about 5
months to implement the modified remedy. The modified remedy can
be conducted in a shorter timeframe because a majority of the
contaminated soil will be shipped by rail off-Site for disposal,
which can be done at a faster rate than if it were treated on-
Site by thermal desorption. The modified remedy would also have
the advantage of less stockpiling and handling of the TPH
contaminated soil, which would reduce worker exposure and the
8
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potential for further release of contamination to the
environment. Based on the above reasons, the modified remedy
better meets the criteria for short term effectiveness.
Implementability
Of the two alternatives, the original remedy will require
more area to implement because it will.require additional area
for stockpiling of excavated soil and for operation of the
thermal desorption system. Also, because the original remedy
would take approximately 11 more months to complete, it would
cause greater disruption to operating businesses on the Site
either as a direct result of excavation and treatment of soil on
their property or from general disruption due to increased
traffic associated with cleanup activities. For these reasons,
the modified remedy better meets this criteria.
Cost
The cost analysis provided in the PRPs' proposal estimates
that the total cost saving of.the modified remedy over the
original remedy will be about $6 Million. A large portion of this
saving is due to the lower cost of off-Site disposal of TPH hot
spot soil compared to the cost for on-Site thermal desorption
treatment for this soil. As stated in the proposal, the cost for
disposal at the Roosevelt Regional Landfill is $59/cubic yard,
which includes the cost of transportation and clean replacement
soil delivered to the Site. Also according to the proposal, the
cost of treating this soil with a thermal desorption system would
be about $95/cubic yard. Therefore, landfill disposal offers a
potential cost sayings of about $36/cubic yard. The modified
remedy is therefore more cost effective and better meets this
criteria.
State Acceptance
Ecology concurs with the selection of the modified remedy.
described above. . -
Community Acceptance
There was little community concern about the proposed ROD
amendment. Only one comment was received, and it was in favor of
the amendment. This comment also proposed that the petroleum hot
spot soil, which is disposed in an off-site landfill, be mixed
with garbage near the surface of the landfill so that air can
diffuse into the soil and the petroleum can be decomposed by soil
bacteria. This is similar to a technique called "landfarming"
which has been used successfully at many other sites to
accelerate the natural biodegradation of petroleum products.
Since long-term confinement of the TPH soil is the main objective
of off-Site disposal,landfarming to reduce TPH concentrations is
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not necessary and may. be too costly for the landfill operators
perform. EPA will inquire whether landfarming is feasible.
to
STATUTORY DETERMINATION
The modified remedy satisfies the provisions of CERCLA
Section 121. The lead and support agencies believe that the
modified remedy remains protective of human health and the
environment, complies with federal and state requirements
identified in the original ROD as ARARs at the time the original
ROD was signed, and is cost-effective.
10
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Attachment A
THE PROPOSAL TO MODIFY THE SELECTED REMEDY
11
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HELLER EHRMAN WHITE & MCAULIFFE
ATTORNEYS
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DAVID M, HSIKECK
(.206)389 6234
Mr. Keith Rose
Superfund Branch (HW-M3)
U.S. Environmental Protection Agency
1200 Sixth Avenue
Seattle, Washington 98101
Re: Allowing off-site disposal of certain TPH-containing soil under the Record of
Decision for the Harbor Island Soil and Groundwater Operable Unit
Dear Mr. Rose:
The Record of Decision ("ROD") that EPA Region 10 issued in September 1993 for
the Soil and Groundwater Operable Unit of the Harbor Island Superfund Site selected a soil
remediation remedy that included excavation and treatment of certain soil "hot spots." These
were defined as areas where (I) Total Petroleum Hydrocarbon (TPH) levels exceed 10,000
mg/kg, (ii) PCB levels exceed 50 mg/kg or (ii) the total risks from mixed carcinogens exceed
1 x 10"*. The ROD requires the latter two categories of soils to be excavated and shipped to
an off-site hazardous waste disposal facility or, as an option for the PCB-contaminated soils,
shipped to an off-site treatment facility for incineration. The ROD specified mat soils
requiring treatment due to their TPH levels are to be treated on-site in a thermal desorption
unit. ,'..*••
As you know, the Prot of Seattle and many of the other current owners and operators
of property within the Soil and Groundwater Operable Unit have agreed to carry out the
remedial action specified in the ROD. Their agreement to carry out this work has prompted
them to closely evaluate the various components of the selected remedy to determine whether
there are any opportunities for making the remedy more cost-effective while not changing its
scope or otherwise making it any less protective of human health and the environment. The
component that appears to offer the greatest opportunity for such enhancement is the
requirement for thermal desorption of all soils haying TPH levels above 10,000 mg/kg. The
PRPs believe that there are strong reasons under the applicable National Contingency Plan
(NCP) remedy selection criteria for exempting soils having TPH levels of between
10,000 mg/kg and 30,000 mg/kg from thermal desorption requirements and allowing them to
be handled in a manner similar to that allowed for certain other contaminated soils at. the
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Mr. Keith Rose
March 24, 1995
Paec 2
site, i.e. through shipment to an appropriate off-site disposal facility. Such an approach
would not only reduce remediation costs significantly but also be simpler to implement and
achieve an overall level of human health and environmental protection relating to these soils
at least equal to that provided by thermal desorption.
The following summarizes the alternative being proposed here and evaluates this
alternative under the remedy selection criteria set forth in'the NCP. We would be glad to
meet with you at your convenience to provide any additional information that you would find
useful regarding this proposal or its acceptability under the NCP criteria.
I. The proposed alternative
The PRP proposal is to remediate the soils having TPH levels of between
10,000 mg/kg and 30,000 mg/kg by shipping these soils to an appropriate off-site disposal
facility, and thereby limit the thermal desorption specified in the ROD to those soils having
TPH levels above 30,000 mg/kg. The PRPs propose to set the upper TPH concentration
limit at 30,000 mg/kg because soils having concentrations below this level almost certainly
will not be designated as toxic dangerous waste under WAC Chapter 173-303, and therefore
will not require disposal at a permitted dangerous or hazardous waste disposal facility.
The PRPs would carry out analyses to identify the soils that have TPH concentrations
within the 10,000 mg/kg to 30,000 mg/kg range, excavate these soils, place them in
closeable containers and ship the containers by rail to the Roosevelt Regional Landfill in
Klickitat County, Washington. The fact that there is an existing rail line on Harbor Island
would make rail shipment simple and cost-effective. Return trains would bring clean soil
from the landfill, which the PRPs would use as backfill for the excavated areas.
This approach would offer several significant advantages over thermal desorption for
the soils in the 10,000 mg/kg to 30,'000 mg/kg TPH range. Many of these advantages are
discussed in the attached letter dated March 21, 1995 from the Regional Disposal Company,
which operates the Roosevelt Regional Landfill (see Attachment A). A principal advantage is
that the affected soils could be remediated much more quickly than would be the case with
thermal desorption. Depending on the schedule that the PRPs adopt, it is estimated that the
affected soils could be excavated, shipped off-site and backfilled with clean soil within two to
five months. This compares to an estimated thirty months, or 2-1/2 years, to carry out
. thermal desorption. The more expedited remediation that off-site disposal would make
possible represents a significant environmental advantage for this option since identical
cleanup levels would be achieved in much less time. It also represents a significant
advantage from the standpoint of implementability, since there would be less overall
disruption to ongoing operations at Harbor Island and less need for prolonged coordination
and EPA oversight of on-site excavation and treatment activities. Disruption also would be
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Mr. Keith Rose
March 24, 1995
minimized because (i) excavated areas could be backfilled quickly, given the short
turnaround time of the rail cars (on the order of two days) that would return clean fill
material to the site, and (ii) the use of clean fill would eliminate the cumbersome analysis
and tracking of thermally desorbcd soils that would be required before these soils could be
used as backfill.
An additional advantage of off-site disposal includes the fact that this option would
reduce potential exposures from soils handling and eliminate the generation of combustion
products that is inherent in operating thermal desorption units. These issues are examined in
some detail in Attachment A. Carrying out thermal desorption requires multiple steps of soil
handling, such as transporting soils on-site to and from the staging area and thermal
desorption unit and returning the treated soil to the excavated areas for use as backfill. Off-
site disposal, in contrast, would merely require placing the soil in containers at the site and
unloading these sealed containers at the Roosevelt Landfill. Less dust generation and
potential exposure to such dust would be involved under this off-site disposal option.
Similarly, as discussed in Attachment A, off-site disposal would eliminate the release of
combustion products that is unavoidable in carrying out thermal desorption. While the dust
end combustion releases would not be environmentally significant their reduction makes off-
site disposal to that extent more effective than desorption.
A further advantage of the off-site disposal option is that it would reduce significantly
the overall cost of remediation at the Soil and Groundwater Operable Unit. Attached to this
letter is an estimated dated March 20, 1995 prepared by Morrispn-Knudsen Corporation
comparing projected remediation costs with and without the option of shipping soils having
TPH levels of between 10,000 mg/kg and 30,000 mg/kg to an off-site disposal facility (see
Attachment B). The estimate concludes that allowing these soils to be shipped to an off-site
facility rather than requiring them to undergo thermal desorption would reduce overall
remedial action costs by more than $6 million.
These environmental, implementation and cost advantages would be achieved without
any reduction in human health or environmental protection relating to the ultimate disposition
of the soils. The landfill to which the soils would be sent for disposal would be the
Roosevelt Regional Landfill in Klickitat County, Washington. The Roosevelt Landfill has
superlative design and location characteristics that provide essentially permanent isolation of
waste materials from the environment. These characteristics, which are summarized in
Attachment A, include engineered systems such as a recompacted two-foot thick clay soil
layer overlain by an 80-mil high density polyethylene plastic liner and other factors such as
the location of the landfill in remote, arid country and its separation from the regional
aquifer by approximately 300 feet of naturally occurring clay. In the unlikely event of a
catastrophic failure of all liner and leachate collection systems it would take approximately
1,500 years for any leachate to reach this aquifer. The landfill also has an exceptionally safe
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Mr. Keith Rose
March 24, 1995
IMCC 4
and reliable rail' transportation system that the PRPr would use for shipping the affected TPH
soils to the facility.
The above factors as presented in more detail in Attachment A demonstrate that the
Roosevelt Landfill option being proposed here would provide a high degree of protection to
human health and the environment. Furthermore, this option is similar in kind to the overall
remediation currently specified in the ROD and would provide comparable protection or
better. Treating the soils at issue here in the thermal desorption unit would remove virtually
all the TPH from such soils. However, it would not remove the metals that often are found
in the Harbor Island soils. The ROD takes this into account by requiring (i) post-description
solidification of any soils that are found to exceed TCLP criteria and (ii) on-site capping of
any soils that, following desorption, are found to contain metals or other constituents below
TCLP thresholds but above the cleanup goals specified in the ROD. The existing ROD thus
already ensures protection of human health and the environment through a combination of
treatment and containment. Allowing the PRPs to dispose of certain TPH soils at the
Roosevelt Landfill therefore would change the overall mix of treatment and containment but
not the fundamental nature of the site remedy. The Roosevelt Landfill option also would be
at least as protective as thermal desorption given (i) the uniquely secure design of the
Roosevelt Landfill and (ii) the ancillary dust and other releases that would occur during
thermal desorption.
II. Application of the remedy selection criteria specified in the National Contingency
Plan
The above discussion provides general information regarding the proposed off-site
disposal of soils having TPH in the 10,000 mg/kg to 30,000 mg/kg range and the
environmental, implementation and cost factors that favor this approach. The above ..
information also is relevant in evaluating this option under the specific remedy selection
criteria set forth in the NCP.
A. The NCP remedy Selection criteria
The NCP establishes nine criteria for evaluating remedial action alternatives. These
are set forth at 40 C.F.R. §300.430(e)(9)(iii), and consist of the following: (1) overall
protection of human health and the environment; (2) compliance with ARARs; (3) long-term
effectiveness and permanence; (4) reduction of toxicity, mobility and volume through
treatment; (5) short-term effectiveness; (6) implementability; (7) cost; (8) state acceptance "
and (9) community acceptance. An approach that would allow the off-site disposal of soils
that contain relatively moderate amounts of TPH ranks at least as high under these criteria as
the current approach that specifies thermal desorption for all soils with TPH levels above
10,000 mg/kg approach under which these soils would undergo thermal desorption.
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•dr. Keith Rose
Irtarch 24, 1995
Page 5
B. Application of (he NCP criteria to (he proposed off-site disposal option
The remedy selection criteria fall into three basic groups. The first relates to the
protectiveness of the remedy and includes considerations of short-term and long-term
effectiveness and compliance with ARARS. This group encompasses the first five of the
criteria listed above. The second group relates to issues of implementability and cost,
corresponding to criteria numbers 6 and 7. The third group concerns the state and
community acceptance of the proposed option and corresponds to criteria numbers 8 and 9.
The following discussion addresses the remedy selection criteria in the context of these three
groups.
1. Overall protection of human health and the environment
Evaluating the proposed off-site disposal option under the NCP criteria that require
remedial actions to protect human health and the environment involves consideration of
essentially two factors. The first and most important consideration is whether the proposed
disposal site would prevent future releases of the TPH and other constituents that would be
iresent in the soils that the PRPs shipped to that facility. The second is an evaluation of the
Effectiveness of this remedy with respect to the Harbor Island site itself.
The information provided in the opening section of this letter describes some of the
design and locational characteristics of the Roosevelt Landfill that make it highly protective
of human health and the environment. Additional information regarding the landfill is set
forth in Attachment A. Of particular relevance in Attachment A are .excerpts from the
Environmental Impact Statements (EISs) that Klickitat County prepared in 1989 and 1992
regarding the landfill. These documents contain objective, thorough evaluations of the
potential environmental impacts that could result from operation of this landfill. The EISs
concluded that adverse impacts were highly unlikely given the combination of state-of-the-art
landfill design, closely supervised operation and locational factors that effectively isolate the
landfill from the local aquifer. These factors remain unchanged and lead to the same
conclusion that the landfill provides exceptional short-term and long-term human health and
environmental protection with respect to the waste materials it accepts.
The off-site disposal option also would provide tangible benefits in terms of human
health and environmental protection at the Harbor Island site itself. The principal benefit
would be prompt completion of a significant part of the overall remedy— as discussed above,
off-site disposal of soils within the 10,000 mg/kg to 30,000 mg/kg TPH range could be
completed within 2 to 5 months as compared to the^jnonths^that might be required to
complete thermal desorption. This option also would provide long-term cleanup effectiveness
at the site because there would be no reduction in the ROD-specified cleanup levels and areas
from which soils would be excavated for off-site disposal would be backfilled with clean soils
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Mr. Keith Rose
March 24, 1995
Pace 6
from the Roosevelt landfill. ARAR compliance would be unchanged since the site cleanup
standards would not vary from those specified in the ROD and the off-site disposal would
comply with all applicable waste transportation and disposal requirements. Lastly, while off-
site disposal would not provide the treatment or permanent reduction in waste volume that
normally is preferred under CERCLA, this does not change the fact that this option would be
(i) protective of human health and the environment and (ii) consistent with the general
approach taken under the current ROD under which the remedy includes a combination of
treatment and containment.
2. Implementability and cost
The second set of NCP remedy selection criteria relates to issues of implementability
and cost. These factors strongly favor the off-site disposal option proposed here.
Implementation of the remedy would be simplified since, as discussed previously, there
would be substantially less handling of the soils in the 10,000 mg/kg to 30,000 mg/kg TPH
range and the opportunity for prompt completion of the excavation, off-site shipment and
backfilling would minimize the time during which ongoing site operations would be
disrupted. The need for ongoing PRP coordination and EPA oversight regarding the
remedial action also would be minimized.
The off-site disposal option also would substantially reduce the remedial action costs
at the site. Attachment B is an estimate prepared by Morrison-Knudsen Corporation
comparing the projected cost of remedial action with and without the allowance for off-site
disposal of soils in the 10,000 mg/kg to 30,000 mg/kg TPH range. This estimate is based on
a careful evaluation of the expected unit costs of the activities associated with the thermal
desorption and off-site disposal options, and on reasonable assumptions regarding the soil
volumes that would be involved and the likely characteristics of those soils. The supporting
documentation included with Attachment A explains these assumptions and unit cost estimates
in considerable detail. The estimate concludes that the off-site disposal option proposed here
would save the PRPs over $6 million. Varying the assumptions could increase or decrease
this amount somewhat. Under virtually any scenario, however, the .cost savings would be
very substantial.
3. State and community acceptance
The final set of NCP remedy selection criteria requires a consideration of whether the
proposed remedy would be accepted by the state and local community. To the PRPs'
knowledge neither the state nor the community have indicated formally whether they would
approve of this proposed off-site disposal. There is reason to believe, however, that they
would not object to such disposal given the expedited cleanup this approach could achieve
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pr. Keith Rose
March 24, 1995
7
and the fact that this option meets the applicable ren.cdy selection criteria set forth at
40C.F.R. §300.430(c)(9)(iii).
HI. Conclusion
Off-site disposal of the soils at the Harbor Island Soil and Groundwater Operable Unit
that have TPH levels between 10,000 mg/kg and 30,000 mg/kg would be environmentally
protective and, on the basis of implementability and cost, preferable to thermal desorption.
For these and other reasons this disposal option also meets the NCP remedy selection
criteria. EPA should take whatever steps are necessary to allow the PRPs to utilize this
option under the ROD.
The Port of Seattle looks forward to your response to this proposal. The other
members of the Harbor Island Soil and Groundwater Operable Unit PRP Group also support
this general proposal but have not yet had an opportunity to review this letter or its
attachments. This approach may require some adjustment in the manner in which certain
fcommon costs would be allocated among the PRPs under their PRP agreement. We are
confident, however, that any necessary adjustments could be made so as to allow this off-site
disposal option to go forward. The Port suggests a meeting between the PRPs and EPA in
the near future to discuss this proposal in more detail.
Very truly yours,
HELLER, EHRMAN, WHITE & McAULIFFE
David M. Heineck
Attachments (2)
cc (w/attachments):
Charlie Ordine
Len Sorrin
Zane Bolen
Tom Kearns
Fred Frederickson
Mark Myers
Tom Newlon
Bill Joyce
Mark Zuschek
Anne DeVoe Lawler
Patrick Paulich
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HELLER EHRMAN WHITE & MCAULIFFE
A 'I" T O K N l:. Y S
6100 COLUMIUA CKNTI.C * r M: i vi k-MM r 01 r«oi i \M«N«i < on rK\ ANCHORAGE
701 Finn AvENi.r. Los Ah.CELES
SEATTLE PALO AXTO
WASHINGTON 9SI04 70QR PORTLAND
FACSIMILE (206! 447 OS49 SAN FRANCISCO
TELErnoNE (200) 447-CfJOO TACOMA
DAV,OM.HR,NT.« • APril U' l995 r-, — (- T= iV ^ ^
(206)389 623*
APR! 1
Mr. Keith Rose
Superfund Branch (HW-113)
U.S. Environmental Protection Agency
1200 Sixth Avenue
Seattle, Washington 98101
Re: Additional information regarding proposed revision to Harbor Island Soil and
Groundwater Unit RD/RA
Dear Mr. Rose:
This is a follow-up to our meeting of April 3, 1995, during which we discussed the
merits of revising the Harbor Island Soil and Groundwater Unit RD/RA to allow off-site
disposal at the Roosevelt Landfill of soils that have TPH levels of between 10,000 mg/kg and
30,000 mg/kg. At the meeting you asked for additional clarification of three matters: (i) the
schedules under which the different remedial options currently being reviewed could be
carried out, (ii) the parameters that Pemco used in developing its estimate of thermal
desorption unit costs and (iii) the thermal desorption production rate that Pemco used in its
cost estimate. This letter and its attachments address these three issues.
The projected schedules for carrying out the three variations of the Harbor Island
RD/RA that we have discussed are enclosed as Attachment A to this letter. The three
variations consist of (i) the current remedial alternative that requires thermal desorption of all
soils having TPH levels of 10,000 mg/kg or more, (ii) an alternative under which all of the
soils having TPH above action levels (and below state dangerous waste thresholds) could be
disposed off-site and (iii) the alternative that would call for a hybrid approach in which soils
having TPH levels between 10,000 mg/kg and 30,000 mg/kg could be shipped for off-site
disposal and soils having TPH at higher concentrations would be treated through on-site
thermal desorption." As you know, the Port of Seattle and the other Harbor Island PRPs are
proposing the third of these options. We have included a schedule showing the second
option for comparison purposes only.
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RECEIVED
JUN 141995
STATE OF WASHINGTON
DEPARTMENT OF ECOLOGY sUPERFUND BRANCH
P.O. Box 47600 • Glympia, Washington 98504-7600
(206) 407-6000 • TOO Only (Hearing Impaired) (206) 407-6006
June 8, 1995
Keith Rose, Superfund Project Manager
U.S. Environmental Protection Agency
Region 10, HW-113
1200 Sixth Avenue
Seattle WA 98101
Dear Mr. Rose:
Ecology has reviewed the revised Harbor Island Record of Decision Amendment dated June 2,
1995, that proposes to conduct fish toxicity tests to determine whether soils exceeding TPH
concentrations of 30,000 mg/kg designate as dangerous waste, to determine whether it is appropriate
to send these soils to the Roosevelt Regional Landfill.
Based on your May 31, 1995, telephone conversation with Mr. Nnamdi Madakor, it is Ecology's
•iderstanding that the Roosevelt Regional Landfill unconditionally accepts TPH-contaminated soils
•p to 5,000 mg/kg. Given that Roosevelt Regional Landfill accepts TPH-contaminated soils up to
the 5,000 mg/kg level, it is the Port of Seattle's or any other PRP's responsibility to ensure that any
TPH-contaminated soils transported off-site that contain greater than 5,000 mg/kg are disposed of
and/or treated appropriately.
The enclosed guideline can be used as a screening test to determine if a waste could potentially fail
the TCLP before the TCLP test is actually conducted.
Ecology hereby concurs with the proposed Record of Decision Amendment.
If you have any questions, please contact Nnamdi Madakor, Northwest Regional Office, at (206)
649-7112.
Sincerely,
Emily Ray< Acting Program Manager
Toxics Cleanup Program
ER:cp
Enclosure
cc: Mike Gallagher, Section Manager, TCP-NWRO
Nnamdi Madakor, Site Manager, Harbor Island, TCP-NWRO
Tanya Barnett, Assistant Attorney General, Ecology Division
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Mr. Keith Rose
April 11, 1995
Page 2
Also included at Attachment A is an description of the assumptions that have been
made in developing these schedules. Common assumptions have been made throughout. As
a result, changing any assumption regarding the time required to carry out a common work
item would change all the schedules equally and would not change the time savings we are
projecting for the hybrid option we are proposing. The time savings would be realized at the
point of remedial action field construction. As these schedules indicate, we are projecting
that this work would require 18 months under the current thermal desorption approach but
only 5 months under the hybrid approach. The remedial action therefore could be completed
13 months more quickly under the hybrid alternative that combines thermal desorption and
off-site disposal.
Attachment B consists of a letter and attachment that responds to your questions
regarding Pemco's cost estimate and the thermal desorption production rate. This
information provides some additional detail regarding the assumptions that Pemco used in
developing its cost estimate. It also provides further information regarding Pemco's rationale
for using a 15 ton/hour thermal desorption production rate in its cost estimate. Please let me
know if this information doesn't adequately respond to your questions regarding these two
issues.
We appreciate your consideration of this p'roposal. We remain available to meet with
you at your convenience and willing to provide additional written information if that would
be helpful in your evaluation of this matter.
Sincerely,
HELLER, EHRMAN, WHITE & McAULIFFE
David M. Heineck
Attachments (2)
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