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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SEATTLE
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                            Scale in Miles
                         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)

-------