Amended Record of Decision
                 (Enforcement Decision Document)
                 Remedial Alternative Selection
     Western  Processing Company, Inc.
     Kent,  Washington

DOCUMENTS REVIEWED

     I am basing my decision primarily on the following documents
describing  the analysis of the cost  and effectiveness of remedial
alternatives  for the Western Processing site.

         Record of Decision and Summary of Remedial Alternative
     Selection, dated September 25,  1985

         Consent Decree

     -   Summary  of Remedial Alternative  Selection  at  the
     Western Processing Company,  Inc.  site.   Final Remedial
     Action.

DESCRIPTION QJL SELECTED REMEDY

     -   Intensive  soil and  waste  sampling on  the Western
     Processing property  (Area I) and  intensive soil  sampling  off
     the property.

         Selective excavation  in Area I  of highly  contaminated
     soils or  non-soil  materials  ("specific  wastes")  before
     groundwater  pumping begins,  with additional excavation
     during and post-pumping  if necessary.   Off-site disposal  of
     excavated  specific  wastes.  Exhume all buried containerized
     wastes, with off-site disposal of all  RCRA hazardous  or
     Ecology  dangerous  or extremely hazardous  wastes.   Excavate
     or plug  all utility and process lines  in Area I.

         After termination of groundwater pumping,  cover Area I
     with a RCRA consistent cap for  closure of a land disposal
     facility.   Maintain cap  for  30 years,  unless period  is
     modified.

     -   Using the results  of the soil  sampling and analysis
     program, eliminate  direct contact threats in the non-Western
     Processing property by excavation of all  soils  which exceed
     the ADI  level or the 1 x 10-5 excess cancer risk level or a
     PCB concentration  of 2 ppm, and by covering all remaining
     surface soils with above background concentrations of  any
     contaminant.  Maintain  the covers for 30 years, unless  the
     period  is modified for  specific areas.   Excavate utility

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     lines leaving Area  I  and going towards  Mill Creek, and
     excavate or plug all other utility  lines  leaving   Area  I.
     Clean utility manholes/vaults near  the site.  Dispose  of
     excavated material  in Area I  or  in an approved off-site
     disposal facility.   Actions will  be limited to those off-
     property soils which may have  been contaminated by  Western
     Processing.    The lead contaminated  house in Area 8  will be
     decontaminated.

          Construct and operate for a minimum of 5 to 7  years a
     shallow groundwater extraction  system which will achieve  an
     inward flow from the boundary  of the currently contaminated
     groundwater  (except for a 50 foot setback along Mill Creek),
     and  which will permanently  achieve  Mill Creek  performance
     standards.  Construct and operate for a minimum of 5 to 7
     years a  deeper groundwater  extraction system which will,
     while the extraction system  is operating,  provide for a
     reversal of regional  groundwater flow along the line  of Mill
     Creek or  which   will  establish  a  hydraulic  barrier  to
     regional groundwater flow  along  the line of Mill  Creek.
     Construct and operate an extraction system to permanently
     reduce the concentration  of trans 1,2-dichloroethylene in
     the  plume  to  less  than 70 ppb.  Construct,  operate and
     maintain  or otherwise  provide  for a groundwater pre-
     treatment  plant.   All extracted water leaving the site shall
     comply with the requirements of Metro if discharged  into the
     sewer system or of Ecology if  discharged into waters  of the
     state.  Groundwater extracted from off-property areas may be
     infiltrated onto  Area I to assist in  the leaching process.

     -    Construct, operate,  and maintain a stormwater  control
     system.

     - ^  Excavate contaminated  Mill  Creek  and east drain
     sediments  which may  have  been  affected  by Western
     Processing.

     -    Intensive monitoring of  Mill  Creek, the east drain,
     groundwater  and the  groundwater  extraction   system
     performance.  Demonstrate compliance  with the Mill Creek and
     trans 1,2-dichloroethylene performance standards  for 30
     years from the termination of pumping, unless modified.

     -    Perform  conditionally   required  actions   if  the
     performance standards are not achieved, or if it appears
     that more than 20 years of groundwater extraction will be
     necessary^  These studies  may  require tests (bench-scale or
     pilot scale) of potential remedial techniques.

DECLARATIONS

     Consistent with  the Comprehensive Environmental Response

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Compensation,  and  Liability Act  of  1980  (CERCLA),  and  the
National Contingency Plan (40 CFR Part 300), I have determined
that the above Description  of Selected  Remedy at the Western
Processing  site is a cost-effective remedy that provide adequate
protection of public health, welfare and the environment.  The
State of Washington has been consulted and  agrees with  the
selected remedy.   Settlements have been  reached between  the
governments (EPA and the State) and the  responsible parties based
on the selected remedy.

     I have also determined that the action being  taken is  a
cost-effective alternative when compared to  the  other  remedial
options  reviewed.  In addition, the off-site  transport, storage,
destruction,  treatment,  and secure  disposal is  more  cost-
effective  than  other  remedial  actions, and  is  necessary to
protect  public health, welfare or  the  environment.  All off-site
disposal shall be in compliance with the  policies stated in Jack
W. McGraw,  Action Assistant Administrator, Office of Solid Waste
and  Emergency Response's May  6, 1985 memorandum entitled
Procedures  for  Planning and Implementing  Off-site Response
Actions,, and any amendments  or supplements thereto.

     If additional remedial actions are  determined   to be
necessary,  a Record of Decision or Enforcement Decision Document
will be prepared for approval of the future remedial action.
     Date                        Regional Administrated

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9/2/86
         Summary of Remedial Alternative Selection  at the
            Western Processing  Company, Inc. site,
                       Kent, Washington
                     Final  Remedial Action

                         INTRODUCTION

     The initial Record of Decision (ROD)  for the Second Operable
Unit at the  Western Processing Superfund Site in Kent, Washington
was signed by the Regional  Administrator on September 25, 1985.
Since then,  two major  actions have occurred  which  affect the the
original ROD.   First,  the results  from  the  Summer 1985
groundwater  field  work were received by EPA in October 1985  and
later  summarized  by  CH2M  Hill in  a Supplemental Remedial
Investigation  (SRI) report dated  July 1986.  Second, negotiations
with the potentially responsible parties (PRPs) concluded with
approximately 180 parties  signing the Phase II consent decree.
The remedial  action will now be undertaken by the consenting
defendants  rather than  the government, and  will be a  final
remedial  action.    Most of  the September 1985  ROD is  still
relevant and appropriate.  The  purpose of this amended summary
for the second operable unit is to document the changes the  new
information  and new circumstance have had on the selection of the
remedy.  This  amended  ROD is essentially an  Enforcement Decision
Document  (EDD) as it  is documenting the  results  of successful
negotiations.

     In the  months since the ROD was  signed, a convention  has
been  established when  identifying  the Western Processing
Superfund site and  its component areas.  The word  "property"   or
"on-property"  is used  to describe the  property owned  by  Western
Processing where  business operations occurred, and is synonymous
with Area I.   (See Figure  1.)  (Area VII  is also owned by Western
Processing, but was used for a  residence.)   The word "site" is
used  to describe Area  I and  the  areas designated  by  Roman
numerals  in Figure 1 in proximity to Area I (but excluding Area
VI.)  The boundaries  of  these  numbered  areas are considered
approximate and  may change if soil contamination is detected
beyond the current boundaries.   The word "off-property" is used
to  describe the entire  site  except  Area  I.   Also,  the word
"governments"  means EPA and  the  Washington Department of Ecology
(Ecology).

                 SITE LOCATION AND DESCRIPTION

     This section  is unchanged.

                         SITE HISTORY

     This section is  unchanged,  except that the major  events
described above have  occurred in the past  year.  The PRPs have

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continued the  stormwater collection and treatment on  the Western
Processing property.

                      CURRENT SITE  STATUS

     The September 1985 ROD states that 13 additional  groundwater
monitoring wells  were  drilled in July and August 1985  to the west
of the  Western Processing property.   These 13  wells plus 10
existing monitoring wells were sampled  to determine  whether the
1,2 trans-dichloroethylene  detected  in  Well  35  had originated at
Western Processing.  (See Figure 2.) Prior to this investigation,
EPA's  consultants considered it unlikely  that this contamination
had migrated to Well 35 from Area I because Mill Creek appeared
to act as a hydraulic barrier  to near-surface groundwater  flow.

     Chemical  data  from the Supplemental  Remedial Investigation
(SRI)  sampling  of these  new and previously  installed monitoring
wells indicate a  plume of  trans-l,2-dichloroethylene  (and  lesser
amounts of trichloroethene and tetrachloroethene) is emanating
from the vicinity of well  21  on the Western Processing property
and is  migrating northwest  both into and beneath  the  creek.
Contaminants  have  been detected as far  west  as well 35.  The
maximum  groundwater concentration of trans 1,2-dichloroethylene
detected in Well  35 has been 900 ppb. The area around  Well  21 has
been determined to  be  the  source.   The maximum  concentration in
Well 21 has been 380,000 ppb. The concentration  decreases  in the
downgradient  direction.   The next  highest concentrations have
been found  east of Mill Creek within the top 40 feet (area of
upward  vertical  migration into the  creek).   Only traces  of
contaminants  have been detected at depths below 80  feet  on the
east side of Mill Creek.

     There are two major transport mechanisms that could possibly
carry contaminants from near the surface  in  the  vicinity of well
21 to the depths  necessary for the  contaminant to flow beneath
Mill Creek: (1) downward vertical  groundwater  flow  or (2) pure
contaminant density  flow.  Because  of  the  extremely  steep
vertical  descent of  the  contaminant and  the  general  upward
groundwater gradient, the most probable mechanism  is density
flow.  Downgradient of the  Well 45 cluster, the contaminant plume
has apparently migrated in a sand zone  that underlies  a  clay/silt
layer at approximately 40 feet.  This sand layer can be traced
laterally as far as well 42 at depths  of approximately 40 to 80
feet, though contaminants have not been detected that far from
Area I.

     While the  SRI  study  showed  that the trans  -  1,2
dichloroethylene in well  35  most  likely did  originate at the
Western Processing property, other, key  aspects of the  generalized
hydraulic conceptual  model were' confirmed.  The capture depth
effect of Mill Creek  was  confirmed to extend  to approximately
this  same sand layer  at  approximately  40 feet  (upward flow

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gradients), followed by a level of predominantly horizontal flow,
then,  at  the below  60 feet level,  downward  hydraulic flow.
Groundwater  flow  directions are to the northwest.

     The other  sections of the Current Site Status section are
unchanged.

                          ENFORCEMENT

     Negotiations with the potentially responsible parties (PRPs)
concluded  in May  1986 with approximately  twenty PRPs  signing  a
stipulation.  This  stipulation gave EPA sufficient moneys (when
combined  with  previously committed  State moneys) to have the
Corps of Engineers  conclude  negotiations  for a  Corps  supervised
remedial design contract,  while also  giving  the PRPs  additional
time to decide whether they wish to sign the consent decree.  The
remedial design contract was not initiated when, on July 2, 1986,
over 120 PRPs submitted  their signatures  to the  governments.  By
the end of  July  over 180 PRPs  had signed the consent decree.
(These 180 consenting defendants are not necessarily the same
PRPs that signed the Phase I consent decree.)   The governments
may sue a number of the  non-settling PRPs for  all  remaining
relief.
                      COMMUNITY RELATIONS

     Community relations activities have continued  since the
September 1985  ROD,  primarily thru  informal  briefings  and phone
updates.  The  proposed  Fund-financed remedy  and the  dioxin
detoxification  (a Phase I consent decree issue)  were the subjects
of Kent City Council briefings.  No new  major  issues have been
raised.  The lawsuit between  a neighboring property owner and a
number of PRPs  is still underway.

     The public comment on this amended ROD and  summary will run
simultaneously  with the Department of Justice comment  period on
the consent  decree.  The  governments' responses to  the issues
raised will  be submitted to the court, as well as being available
to the public.


                    RECOMMENDED ALTERNATIVE

     The recommended alternative  is  the  remedy which has been
negotiated with consenting defendants.  This  remedy is  described
primarily in Appendix B of the Phase II Consent Decree (consent
decree.)  Appendix B is entitled "Scope  of Work for  Addressing
Soil and Groundwater Contamination at and Emanating from the
Western Processing  site."

     For the most  part,  the  consent decree remedy  is  either
identical to,  or substantially the  same as,   the alternative
selected  in the  original September  1985 ROD.    (See  Table  1.)

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The differences  between the remedy in the consent decree and  the
September 1985 ROD fall into 3 classes:
          1.  The actions  had  been foreseen as part of  the remedy
outlined in the  ROD, but were  expected to occur after the first  5
to 7 years of remedial action.   (The September 1985 ROD selected
an interim remedy.)  These  "Future  Actions" included a RCRA
compliant cap,  long-term  O&M,  and long-term groundwater  and
surface water monitoring.   The future actions are  now part of  the
selected remedy  in the consent decree.
          2.     The  original purpose of  the  remedy  in  the
September 1985 ROD is  still achieved, but the schedule  or phasing
or approach  is  different.   In  some of these situations,  the
selected remedy  in the consent decree  is  more specific  where  the
ROD was more general.  These changes alone would generally  not
have required the September 1985 ROD to be  amended.  Examples of
these include the on-property soil  excavation and  the  allowable
concentrations in Mill Creek;  and
          3.   Further actions were  to be planned if they became
necessary because of new  regional groundwater data. Because  the
new information confirmed regional  groundwater contamination by
trans 1,2, dichloroethylene, remedial  actions and possible still
further future actions have been added to remedy  this situation.

     Therefore, the following components  are proposed  for  the
remedial  action.   These include most of the elements of  the
September 1985  ROD.

     -    Intensive soil  and  waste  sampling  on Area I  and
     intensive soil  sampling off the property.

     -    Selective  excavation in Area I of  highly  contaminated
     soils  or   non-soil  materials  ("specific  waste")  before
     groundwater pumping begins,  with additional excavation
     during and  post-pumping  if necessary.   Off-site disposal of
     excavated specific wastes.  Exhume all buried containerized
     wastes, with  off-site disposal of all RCRA hazardous or
     Ecology dangerous or extremely  hazardous wastes.   Excavate
     or plug all utility and process lines in Area I.

          After  termination of groundwater  pumping,  cover Area  I
     with a RCRA consistent cap for closure of a land disposal
     facility.   Maintain cap for  30  years, unless  period is
     modified.

     -    Using  the results  of  the soil sampling and analysis
     program, eliminate direct contact threats in  the non-Western
     Processing  property  by excavation of all soils  which exceed
     the ADI level or  the 1 x  10-5 excess cancer  risk  level or  a
     PCB concentration of 2 ppm, and by covering all remaining
     surface soils with above background concentrations of  any
     contaminant.  Maintain the covers for 30 years, unless  the
     period is  modified  for  specific  areas.  Excavate  utility

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     lines  leaving Area  I  and  going towards  Mill  Creek,  and
     excavate  or plug all other utility lines  leaving  Area  I.
     Clean  utility  manholes/vaults near  the  site.   Dispose
     excavated material in Area I or in an  approved off-site
     disposal  facility.   Actions will be limited to those off-
     property soils which may have  been  contaminated by Western
     Processing.   The lead contaminated house in Area 8 will be
     decontaminated.

     -    Construct and operate for a minimum of 5  to 7 years a
     shallow groundwater  extraction  system which will achieve  an
     inward flow from the  boundaries of the area  depicted in
     Figure 3,  and  which will permanently achieve  Mill Creek
     performance standards.  Construct and operate for a minimum
     of 5 to 7  years a deeper groundwater extraction system which
     will,  while the extraction  system is operating,  provide for
     a reversal of regional groundwater flow along the line of
     Mill Creek or which will establish a hydraulic barrier to
     regional  groundwater flow along the  line of  Mill Creek.
     Construct and operate  an extraction system to permanently
     reduce the concentration of trans 1,2  dichloroethylene in
     the  plume to  less  than 70 ppb.  Construct,  operate  and
     maintain   or  otherwise provide for  a  groundwater  pre-
     treatmeht plant.  All extracted water leaving the site shall
     comply with the requirements of Metro if discharged  into the
     sewer  system or of Ecology  if  discharged into waters of the
     state.  Groundw.ater  extracted from off-property areas may be
     infiltrated onto Area I  to assist in the  leaching process.

     -    Construct,  operate, and maintain a  stormwater control
     system.

     -    Excavate contaminated  Mill  Creek  and  east drain
     sediments which  may  have  been  affected  by Western
     Processing.

     -    Monitor intensively Mill Creek,  the east  drain,
     groundwater  and   the  groundwater  extraction  system
     performance.  Demonstrate compliance with the Mill Creek and
     trans  1,2-dichloroethylene performance standards  for 30
     years  from the termination of pumping, unless modified.

         Perform  conditionally  required  actions  if  the
     performance standards are not achieved, or if it appears
     that more than 20 years of groundwater extraction will be
     necessary.  These  studies may  require tests (bench-scale or
     pilot  scale)  of potential remedial techniques.

     Where  the  proposed actions  are different  from the September
1985 ROD, the  proposed actions should be considered additional
alternatives to those alternatives previously  evaluated in the
Feasibility Study and the 1985 ROD.

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     This remedy is designed to  be a final  operable unit.
However,  additional actions  may be  necessary under certain
circumstances.  First, if the selected  remedy is unsuccessful  in
meeting the performance standards, new or different technologies,
such  as  in-situ  soil  stabilization,  may be  considered and
addressed in an  additional amended  ROD  after  the consenting
defendants  request  Government  approval  of  such treatments.
Second, remedies of deep (regional) groundwater contamination
discovered by the monitoring well network  (with  exception of the
trans 1,2 dichloroethylene  involving Well 35) is not covered  by
the remedial actions.  However, it is also not  included  in the
releases  being  given  to  the consenting defendants.  The  consent
decree specifically states that the consenting defendants  and the
governments shall enter negotiations if any plume suspected  as
originating at Western Processing is found  west of Mill Creek.

     A further discussion of the recommended alternative follows.
Where the recommended alternative is identical to  or similar  to
the  September  1985  ROD,   no  discussion  is repeated  in  this
document.   Where  the recommended alternative  is different  than
the alternative  in the  September  1985 ROD, an  explanation  is
given.   The change may  be  justified  by significant  new
information,  consideration  of  cost-effectiveness;  adequate
protection of public health, welfare, and the environment;  or
compliance  with  other  applicable  or  relevant environmental
standards.

On-prooerty  (Area H Soils

     The  recommended  alternative  for Area I soils  is  identical
to the  alternative  in the  September 1985  ROD except  for:
Dspecific waste excavation  criteria and timing;  2) containerized
waste disposal; and 3) RCRA  compliant cap and maintenance.

     The  September 1985 ROD  stated that the results  of  a  testing
and sampling program would define the selective excavation  of
highly contaminated  (non-containerized)  soil  and  non-soil
material.  The purpose of the excavation was  to reduce the  source
strength,  but  no  criteria was  specified.   The  cost-estimate was
based on excavating  and disposing off-site 10,650 cubic  yards,
but the ROD went  on to say that the quantity (and thus  the cost)
could not  be accurately  determined until  the sampling  is
completed.

     The proposed remedy continues to base the selection  of the
material to be excavated on the results  of an Area I soil and
waste sampling  and analysis program.  The primary  difference  is
that the consent  decree specifies the criteria  which should  be
used  to  select  the  most  troublesome source  material.  The
criteria include  1) the contaminants  may not be cost-effectively
removed by in-situ leaching and which could, by their  presence,

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prevent  compliance with the  Mill Creek water quality performance
standards; or 2) the contaminants may, because  of their location
or  physical or  chemical  properties,  migrate beyond  the
hydrogeologic boundary of Mill Creek; or  3) the material  may
adversely affect  the stability  of  a cap  over  Area I.   The
secondary difference  is  that the  consenting defendants  are
required to remove  10,000 cubic yards prior  to pumping.   The
Governments may require additional  excavation at any time if
compliance with Mill Creek standards  or the stability of the cap
is at risk.

     The September 1985 ROD assumes that all exhumed drums and
other containerized materials would  be disposed off-site in an
approved facility.  The proposed  remedy will  require off-site
disposal of  all RCRA hazardous wastes and Ecology dangerous or
extremely  hazardous  wastes.   However,   if  the  exhumed
containerized material is not hazardous, the material  may be
replaced into Area I under the clean  cover  and eventual RCRA cap.

     All of the above changes are  consistent with the original
purpose of the  Area  I excavation.  However, these changes  will
the remedy more cost-effective while  maintaining the same public
health and environmental protections as the original remedy.

     The third change is the addition of a cap consistent, with
the  criteria in  the RCRA  regulations  for closure  of  a  land
disposal facility (landfill)  in effect at the time of entry of
the  consent decree.  The  September 1985 ROD envisioned  site
close-out to include such a cap.  Also, compliance with other
environmental  laws  and  standards require that such a  cap be
placed over Area I  as some hazardous wastes will be left on site.
The 1985 Feasibility Study estimated that the cost  of  the cap
would be approximately  $2,900,000.   The cap  maintenance
provisions are also consistent with RCRA.

Off-Property Soils  and Issues

     The recommended alternative  for the off-property soils is
identical to the alternative in the September 1985 ROD except the
period  of maintenance  for the cover  is specified.    Both
alternatives  require  that  soils  contaminated with above
background concentrations of contaminants which may have  come
from Western Processing activities  be  covered.   This cover may be
soil or  asphalt but must have a permeability less than or equal
to  the  permeability of  the subsoil.  The September 1985  ROD
acknowledges that the cover  will have  to be  maintained for a
minimum of 30 years, but the selected remedy covered by that ROD
covered  only the first 5 years.  The consent decree requires the
consenting defendants provide foj: the maintenance of the cover
for a period of 30 years.  This requirement may be modified for
specific off-property areas  if, for example,  the property owner
develops or paves a parcel for his  own benefit or use.

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     The other  proposed  off-property actions for direct  contact
hazards  (cleaning the  lead  contaminated house  in Area 8  and
inspection  and  cleaning  utility vaults)  are  also unchanged  from
the September 1985 ROD.

Selection of Disposal Facility

     The proposed alternative is virtually identical with the
September 1985 ROD.   Both alternatives involve both Area I and
off-site disposal.   Government  approval for  the  use  of  any
particular off-site facility will  still  be based  on   the
requirements specified  in the Hay 6, 1985 memorandum entitled
"Procedures for  Planning and Implementing Off-Site Response
Actions" from Jack W. McGraw, EPA Acting Assistant Administrator
for Solid Waste  and Emergency Response,  or any amendments or
supplements.  If, however,  government approved facilities in
Region 10 are unavailable, a variety of steps  must  be taken by
the consenting  defendants, including consideration  of  temporary
storage  and  consideration  of  government approved  disposal
facilities in Regions 8 and  9.  If all these options are out of
the question, the consenting defendants  and  the government  will
negotiate to develop an  acceptable alternative.  The alternatives
to be considered would include  treatment and destruction.  If the
selected remedial action is anything other than disposal  at  a
government  approved  hazardous  waste  facility,   a public  comment
period and an amended ROD may be  necessary.

Shallow Groundwater

     The shallow groundwater  proposed actions in the  consent
decree  are  largely similar to the  selected actions  in   the
September 1985 ROD.  To ensure  that there will be no degradation
of the shallow groundwater  beyond  the  currently contaminated
zone, the consenting defendants will  be required, throughout the
pumping period,  to achieve a shallow groundwater flow inward  from
the  boundaries  of  the  contaminated  zone.  (See Figure 3.)
Compliance  with this performance  standard will be  monitored by
checking the  water  levels  in new  and existing monitoring wells.
An exception has been added for a 50 foot  set-back from   Mill
Creek to avoid  drying up the creek.   This change is more cost-
effective and protective of the environment.

    Mill Creek performance standards  (see below) must also be met
during and after pumping. A demonstration  that the Mill Creek
performance standards  will  be met on a permanent basis after
ceasing pumping  is  the  key  criteria for  determining when the
shallow groundwater pumping may terminate. This criteria for
determining  when groundwater extraction  may cease  is consistent
with the September 1985 ROD.  The September 1985 ROD included  a
period  of five  years of pumping,  to  be followed  by a major
reassessment of  this activity.   The consent  decree's minimum

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pumping period of 5 to 7 years will provide a large degree of
improvement in the shallow groundwater quality ,  particularly in
the more mobile organics.

     The selected remedy  in the September 1985 ROD allowed low
capital cost in-situ chemical  leaching techniques to be used
after  monitoring  the site  to  ensure  that  adequate gradient
control had been established and  after sufficient laboratory
scale  testing.  These  techniques  may  also  be  applied by the
consenting  defendants  under the  consent  decree  after  they
specifically ask for and receive the governments' permission.
The consenting defendants may also ask  for permission to apply
other techniques which may become more feasible in the future,
such as  in  situ solidification,  but a more detailed review,
including public comment  and an amended ROD,  would be necessary
prior to the governments'  approval.

Regional Groundwater

     The September  1985  ROD stated that additional remedial
activities  may be required to  complete the site response if
contamination from Western Processing is found  in the regional
aquifer.  The proposed alternative addresses regional groundwater
contamination in 4 ways:   1) clean-up of  the only known plume; 2)
reverse regional groundwater flow  along  approximately 1800 feet
of Mill  Creek, or establish  an hydraulic  barrier to regional
groundwater flow  along the same  line;  3)  extensive regional
groundwater  monitoring;  and 4) groundwater use restrictions.

     The consent decree  requires that the concentration of trans
1,2-dichloroethylene be reduced to below 70 ppb throughout the
plume prior to termination of the groundwater extraction system
for  this  portion  of the  clean-up.  The proposed Recommended
Maximum Concentration Limit in  drinking water  (50 FR 4688,
November  13, 1985)  for trans 1,2-dichloroethylene is 70 ppb.
While  no one is  currently using or drinking this groundwater,
this proposed drinking water criteria is  the relevant environment
standard.  This  level of  clean-up is to be achieved by source
removal  from Area I during the specific waste  removal and by
installing  wells specifically placed and designed  to  extract the
trans 1,2-dichloroethylene already beyond the boundary of Area I.

     The requirement  to  reverse groundwater flow at a depth of 40
to  70  feet at  approximately Mill Creek,  or to  establish an
hydraulic  barrier  to   the  regional  groundwater  flow  at
approximately the same  location,  will insure that no new  regional
groundwater plumes will escape from Area I and pass under Mill
Creek.   In addition,  the extraction  wells in  the regional
groundwater  may  provide for earlier and  easier detection of any
plume  which has bypassed  the creek and  the existing monitoring
net.  These steps are necessary to protect the  groundwater for
future use.  They are also cost-effective as it is less expensive

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to clean-up  a smaller  area  of  groundwater contamination than to
clean-up  a  large plume.   The groundwater flow reversal would
probably be achieved  by placing extraction wells screened at  the
50 to 70 foot depth within Areas I and IX.  The hydraulic barrier
would  be  achieved by  placing  extraction wells  very near  the
creek,  including the  west side of the creek.

     The  consent decree also does not give the consenting
defendants  any release of liability  for regional groundwater
contamination except  for  their clean-up of the only known plume.
If further  regional  groundwater contamination is  ever detected,
all PRPs may be held  liable  and required to remedy the situation
and/or  repay the governments' costs.

Discharge  of Extracted Groundwater

     The cost estimates in the September 1985 ROD assumes that
all extracted groundwater would be  pre-treated and discharged to
the Metro sewer and  treatment system.  This is still the most
likely disposal option  for all groundwater extracted from Area I
or any other highly  contaminated  area.  The proposed alternative
expands the disposal options  for  the uncontaminated or only
slightly contaminated groundwater which may be extracted as part
of the regional  or  even shallow off-property groundwater
extraction  system.   These additional options are discharge into
a surface water  body  in compliance with the  requirements  of
Ecology pursuant to the NPDES system, or infiltration into Area I
to assist the  leaching process.   These alternatives were raised
when it was realized  that  the quantity of  water that may be
produced from the newly required regional groundwater actions  may
exceed  the capacity of the local sewer system.  These changes  are
consistent with applicable  and  relevant  environmental standards
and criteria.  For uncontaminated  or slightly contaminated water,
these alternatives may  be more  cost-effective than  discharge  to
Metro.   Infiltration of stormwater into Area I prior to  cap
placement to  aid the  leaching  program was the  recommended
stormwater  alternative  in the September 1985 ROD.  Infiltration
of groundwater prior to cap placement to also aid the leaching
program is a extension  of the same idea.

     Creek

     The objectives  for remedial  action in Mill Creek are still
the objectives in the September  1985 ROD.  The objectives will
still be met by groundwater  control, shallow groundwater quality
improvement  (from specific waste excavation,  leaching,-   and
groundwater extraction), and sediment excavation.

     As a result of negotiations, .numerical performance standards
for water quality  in  Mill Creek were developed.  (Table 2.) These
numerical performance standards  are consistent with the approach
described in the  September  1985 ROD.  The  calculation of  the

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maximum allowable downstream concentration for each pollutant
considers both the ambient water  quality criteria for aquatic
organisms  and the  upstream  (background)  concentration.   As
Ecology's long-term goals of improving upstream  water  quality are
achieved,  the  consenting defendants will be required to meet more
rigorous Mill  Creek performance standards.

     As in  the  September 1985  ROD,  the shallow groundwater
concentrations which  will allow these Mill Creek performance
standards to be permanently achieved  will  require over 99% of the
available  (mobile)  zinc and and  a  high percentage of  the
available (mobile) cadmium to  be  removed from the site.

     The recommended alternative still includes the  Mill Creek
and east drain sediment testing and  excavation  program.   The
minimum reach which will be tested  has  been slightly shortened at
the downstream end, but will still  include 300 feet downstream of
the east drain discharge into  Mill  Creek.

Stormwater controls

     The recommended stormwater remedial actions are unchanged.

Monitoring

     The recommended  monitoring  program  is  unchanged.   The
consenting  defendants are required to continue  the extensive
monitoring  program for at least 30 years from the cessation of
pumping to demonstrate full compliance with the  consent decree.

Land and Groundwater Use Restrictions

     The consent decree requires  the consenting  defendants to use
their best efforts to place groundwater, and,  in the case of Area
I, land use restrictions  in  the county property records.   The
September 1985 ROD foresaw the need  for such restrictions.   The
land use restriction on Area  I follows the wording in the RCRA
regulations at  40 CFR 264.120 and  264.117(c)  and states  that
post-remedial  action land use is restricted such that use of the
property must never be allowed to disturb the  integrity of the
final cover, or any other component of any  containment system, or
the function of the monitoring system.

     The groundwater use restrictions will also be placed in the
county  property  records.   The  groundwater restrictions  will
ensure that there will be no  threats to public health from any
contaminated groundwater.

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Community Relations

     Proposed community  relations activities are unchanged from
the September  1986 ROD.  The governments will maintain the lead
for the community relations activities, but the consent decree
outlines activities where  the  consenting  defendants and their
contractors  will  cooperate with the  governments' activities.

Other Issues

     Floodplain protection is unchanged from the September 1985
ROD.

Costs

     No cost breakdowns are available.  The consenting defendants
have estimated that the cost  of the  remedy is approximately
$40,000,000.  This cost estimate is consistent with  the cost
estimates in the  September 1986  ROD.

          CONSISTENCY WITH OTHER ENVIRONMENTAL LAWS

     The list of federal  and  state  applicable  and  relevant
environmental  standards, criteria, guidance, and advisories are
unchanged from the September 1985  ROD.

     The recommended  alternative is  currently  considered a final
remedy.  However, as summarized  under Future Actions, items which
are currently unknown may require  future evaluation and  actions.

     Aspects of the recommended alternative which are consistent
with the  applicable  and relevant portions of RCRA  regulations
include:

     -    A  cap over Area I designed to be  consistent with RCRA
     regulations for closure of a land disposal facility,  and
     maintenance  of this cap.

          The off-site soil cover design and maintenance

     -    Groundwater monitoring

          Land  and groundwater use  restrictions  in Area I and
     other areas

     The recommended alternative is still consistent  with the
Assistant Administrator's  application of RCRA to  the  Crystal
Chemical  CERCLA  site.  The federal  Water  Quality Criteria for
aquatic organisms are still used  to  set Hill  Creek  performance
standards,  but a factor has been added to reflect the  variable
quality of the  upstream  (background)  water  quality.   The
performance standard  for  the trans  1,2-dichloroethylene  is

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consistent with the RMCL proposed under the Safe Drinking Water
Act.  All other elements are consistent with the statements in
the September 1985 ROD.

     Ecology has been an active participant in the negotiations
and supports the remedy described  in  the consent decree and this
amended ROD summary.

                   OPERATION AND MAINTENANCE  (O&M)

     The O&M activities required to ensure effectiveness  of the
remedy include:

     Operation  of the  groundwater  extraction  and treatment
     systems as  long as necessary

     Maintenance  of the RCRA cap, off  property covers, and the
     stormwater control system for 30 years

     Long-term monitoring of the shallow and deep groundwater and
     Mill  Creek,  including  30  years  of monitoring after
     termination of groundwater extraction

     All  O&M activities  will  be the responsibility of  the
consenting dependents.

                        SCHEDULE

     - Soil and  waste sampling program
          stipulation filed                 August 15, 1986

     - Soil and  waste sampling              September to November
                                             1986

     - Consent decree lodged                September 1986

     - Detailed  work plans received
          from the consenting defendant's
          contractor                        February 1987

     - Start construction                   Spring-Summer 1987

     - Start groundwater extraction         1988

                           FUTURE ACTIONS

     No  future  actions  are presently expected.   However  as
discussed  above,  mechanisms are in place for initiating new or
revised  actions if  they are necessary.  Areas were additional
actions may be necessary include: '

     -    Regional groundwater if another plume  is detected.

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     New technologies for soil stabilization or treatment
that may arise as a result of conditionally required
actions, application of the McGraw policy, or at the  request
of the  consenting dependents.

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FIGURE  1

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     RAILROAD
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              ~\
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                                                                                    -HH
                                                                                                        -H+-
                                                                                FENCE LINE—^
                   ^
                                                                                            WESTERN PROCESSING
                                                                                                    SITE
                                                                                                                     JITC
                    VACANT HOUSES
                                                                        MW-53
                                                                  MW-54@S)@MW-52 \DW-34 S.D.
                                                      MW-47-
                                                     MW-48®|xU§'UW-45
                                                           T) MW-46
r^
s*










MV
                                                                                       MW-50
                                                                                  MW-5I®S)®MW-49V
                       SOUTH  196lh SI.
 ^
1
 1
                                                              INDUSTRIAL PARK
      LEGEND:                        ' (

0  SluNo.

9>  Wellt Inttilltd end Sampled During Summer 1985

O  Exiiting Welli Sampled During Auguit 1985
                                        G
 &  Exiiting Well Abandoned
                                                                           OMW-35
                                                                                                                                    >


                                                                                                                                    T>
                                                                                                                                    C
                                                                                                                                    CM
                                                                                                                                    f.
                                                                                                                 Scale: 0
                                                                                                                                 200
                                                                                                                            100
                                                                                                         F10ur*2

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     Area of Inward  Shallow
     Groundwater Flow
   50 ft. Buffer
from Mill Creek
                                      FIGURE  3

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                             TABLE 1

       MAIN ELEMENTS QF THE CONSENT DECREE SELECTED REMEDY

                                   Similar       Different
                                     to             from
                               September 1985  September 1985
                                    ROD              ROD
General Requirements

Health and Safety Plan
Quality control/quality
  assurance plan for samples
  and analysis
Selection of Off-site disposal
  facility
Floodplain protection
Area I stormwater system

Area J. Soils

Non-destructive subsurface
  geophysical survey
Soil/waste sampling and
  analysis program
Excavate containerized wastes
Excavate specific wastes
Excavate and dispose off-site
  all PCB's over 50 ppm
Plug or excavate utilities
Control stormwater runoff
Clean fill for a work surface
RCRA cap and maintenance

Off-Property Soils and Issues

Soil sampling and analysis
  program
Non-destructive geophysical
  survey
Excavate hots spots over ADI
  or over 10-5 excess cancer
  risk or PCB's over 2 ppm if
  contamination may have been
  from Western Processing
Cover soils with concentrations
  over background if contamina-
  tion may have been from
  Western Processing
Always required

Always required
X
X
X
X

X
X
X
X
X
X

X
                X (2)*
                X (2)
                X (1)

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Non-extremely hazardous waste
  may be brought onto Area I          X
  and placed under the cap
Maintain cover                                        X  (1)
Clean the house in Area VIII          X
Test and clean live utilities         X

Groundwater and Mill Creek

     Specific Actions

Shallow groundwater extraction
  from the  contaminated                              X  (2)
  on and off-property areas
Regional groundwater extraction
  wells for trans-1,2 dichloro-
  ethylene extraction, and to                         X  (3)
  reverse the flow or to esta-
  blish a hydaulic barrier
Discharge groundwater to:
  Metro                               X
  Surface water                                       X  (2)
  Area I infiltration                                 X  (2)
Minimum 5-7 years of pumping                          X  (2)
In-situ enhanced leaching             X
Monitoring programs                   X
30 year post-pumping compliance
  period                                              X  (1)
Groundwater use restrictions                          X  (1)
Excavate and restore Mill Creek
  and the east drain                                  X  (2)

     Performance Criteria to Cease Pumping

Achieve Mill Creek performance
  standards for aquatic organisms                     X  (2)
Reduce trans 1,2-dichloroethylene
  to 70 ppb throughout the plume                      X  (3)

Other Issues

On-going Community Relations
  Activities                          X
Deed/title restrictions                               X  (1)

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 *   (1)  The actions had been foreseen as part of the remedy in
the September 1985 ROD, but were planned to occur after the first
5 to 7 years of remedial action which were covered by that ROD.

     (2)   The concepts  and final  criteria or  protection  are
similar to the selected remedy in the September 1985 ROD,  but  the
approach or phasing is different.

     (3)  Because regional groundwater contamination by trans  1,2
dichloroethelene from Western Processing has  been confirmed,  new
elements are being added to the selected remedy.

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                           TABLE 2.

               MILL CREEK PERFORMANCE STANDARDS

Consent Decree, Appendix  B

Section IV. D. 4.   Allowable Concentrations  in Mill Creek

          a.   If  the concentration of a Mill Creek indicator
chemical or other priority pollutant at the upstream  (background)
monitoring point  in Mill Creek is less than two-thirds of the
applicable upstream  Federal Ambient Water Quality Criterion for
Aquatic Organisms (Water  Quality  Criterion),  the  maximum
allowable concentration at  the downstream compliance point  shall
be the downstream Water Quality Criterion.

          b.   If  a Water Quality  Criterion is not achievable
because the upstream (background) concentration  of  a  chemical  is
near or above the Water Quality Criterion, the maximum allowable
concentration at the downstream compliance point shall be the
level described below:

              (i)   If  the  concentration  of a Mill  Creek
indicator chemical or other priority pollutant at the upstream
(background)  monitoring point in Mill Creek is at or above two-
thirds of the upstream  Water Quality Criterion, the  maximum
allowable concentration at  the downstream compliance point  shall
be no more than the background concentration plus  fifty percent
of the background concentration; or

              (ii)   If  the  concentration of  a Mill  Creek
indicator chemical or other priority pollutant at the upstream
(background)  monitoring point in Mill Creek is at or above the
upstream Water  Quality Criterion,  the maximum allowable
concentration at  the downstream compliance point  shall be  no
greater than background plus eighty percent of the upstream WAter
Quality Criterion.


The  applicable  Water Quality Criteria shall  be those final
criteria  published  in the Federal Register as of the date  of
entry of this Consent Decree.

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