PB95-964108
                                 EPA/ROD/R05-95/280
                                 February 1996
EPA  Superfund
       Record of Decision:
       Muskego Sanitary Landfill,
       Muskego, WI
       2/2/1995

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                           DECLARATION

                        RECORD OF DECISION
                SELECTED REMEDIAL ALTERNATIVE FOR
                     GROUNDWATER FINAL REMEDY
                  FOR MUSKEGO SANITARY LANDFILL
Site Name and Location:

     Muskego Sanitary Landfill
     Muskego, Wisconsin

Statement of Basis and Purpose:

This decision document presents the selected remedial action for
the Muskego Sanitary Landfill located in Muskego, Wisconsin.  The
decision has been developed in accordance with the Comprehensive
Environmental Response, Compensation, and Liability Act  (CERCLA) ,
as amended by the Superfund Amendments and Reauthorization Act
(SARA) ,  and in accordance with the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP) to the extent
practicable.  The attached index identifies the items that
comprise the Administrative Record, upon which the selection of
the remedial action is based.

Assessment of the Site:

Actual or threatened releases of hazardous substances from this
site, if not addressed by implementing the response action
selected in this Record of Decision (ROD), may present an
imminent and substantial endangerment to public health, welfare
or the environment.

Description of the Selected Remedy:

The Final Remedy addresses protection of ground water and
potential exposure to ground water through engineering controls.
Institutional controls have already been initiated through the
interim source control action.  The principal threats are direct
exposure to contaminated groundwater through ingestion or
inhalation at private wells.  This remedy is described as
follows:

o    Monitor groundwater throughout the site,
o    Conduct a groundwater pumping test(s),
o    Install and operate groundwater extraction in the vicinity
     of the Non-Contiguous Fill Area,
o    Perform on-site treatment and discharge of extracted
     groundwater from the Non-Contiguous Fill Area,

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o    Discharge treated water to an on-site infiltration basin in
     accordance with state standards, and
o    Dispose of treatment residuals, if generated, to an approved
     disposal facility.
o    Monitoring and evaluation of the effectiveness of the
     groundwater extraction system in achieving progress toward
     cleanup standards, and
o    Expansion of the system if data on the performance of the
     system indicates that expansion is necessary to make
     progress toward cleanup standards:

State Concurrence:

The State of Wisconsin concurs with the selected remedy.  The
letter of concurrence is attached to the Record of Decision (ROD)
package.

Declaration:

The selected remedy is protective of human health and the
environment, attains Federal and State requirements that are
legally applicable or relevant and appropriate to the remedial
action, and is cost-effective.  This remedy utilizes permanent
solutions and alternative treatment technology to the maximum
extent practicable for this site. .Because this remedy will
result in hazardous substances remaining on-site above the
health-based levels, a review will be conducted within 5 years
after commencement of remedial action,  to ensure that the remedy
continues to provide adequate protection of human health and the
environment.
Datef .                          / Valdas V.  Adamkus^
                                      Regional Administrator

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            SUMMARY OF REMEDIAL ALTERNATIVE SELECTION
                  MUSKEGO SANITARY LANDFILL SITE
                        MUSKEGO,  WISCONSIN

                        TABLE OF CONTENTS
I.   SITE NAME AND LOCATION	 1


II.  SITE HISTORY AND ENFORCEMENT ACTIVITIES	 3


III. COMMUNITY PARTICIPATION.	,	 6


IV.  SCOPE OF GROUNDWATER REMEDIAL ACTION	 7


V.   SITE CHARACTERISTICS	 8


VI.  SUMMARY OF SITE RISKS	 14


VII. DESCRIPTION OF ALTERNATIVES	21


VIII. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES  30


IX.  THE SELECTED REMEDY	 39


X.   STATUTORY DETERMINATIONS	 42


XI.  RESPONSIVENESS SUMMARY	 47


XII. INTERIM GROUNDWATER MONITORING PLAN	Attachment A


XIII. PERFORMANCE EVALUATIONS OF PUMP & TREAT 	Attachment B


XIV. ADMINISTRATIVE RECORD	 Attachment C


XV.  STATE CONCURRENCE LETTER	Attachment D

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                      DESCRIPTION OF FIGURES

                  MUSXEGO SANITARY LANDFILL SITE
                        MUSKEGO,  WISCONSIN
FIGURE 0

FIGURE 1

FIGURE 2

FIGURE 3

FIGURE 4

FIGURE 5

FIGURE 6

FIGURE 7

FIGURE 8
SITE LOCATION MAP

SITE MAP

WASTE MANAGEMENT OF WISCONSIN,  INC.  PROPERTY

WATER TABLE MAP

SAMPLING LOCATIONS (SOUTHERN FLOW PATH)

SAMPLING LOCATIONS (SOUTHEAST FLOW PATH)

SAMPLING LOCATIONS (NON-CONTIGUOUS FILL AREA)

SAMPLING LOCATIONS (NORTHERN PERIMETER)

SAMPLING LOCATIONS (PRIVATE WELLS)

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TABLE 1


TABLE 2


TABLE 3


TABLE 4


TABLE 5


TABLE 6

TABLE 7


TABLE 8



TABLE 9


TABLE 10
       DESCRIPTION OF TABLES

   MUSKEGO SANITARY LANDFILL SITE
         MUSKEGO,  WISCONSIN

ORGANIC GROUP RESULTS.  ROUNDS 1 AND 2 GROUNDWATER
SAMPLES

NR 140 AND EPA MCL EXCEEDANCES FOR GROUNDWATER IN
SOUTHERN FLOW PATH

NR 140 AND EPA MCL EXCEEDANCES FOR GROUNDWATER IN
SOUTHEAST  FLOW PATH

NR 140 AND EPA MCL EXCEEDANCES FOR GROUNDWATER IN
NON-CONTIGUOUS FILL AREA/ANAMAX FACILITY

NR 140 AND EPA MCL EXCEEDANCES FOR GROUNDWATER IN
NORTHERN WELLS

POTENTIAL EXPOSURE PATHWAYS FOR FUTURE LAND USE

EXPOSURE PARAMETERS FOR INGESTION OF GROUNDWATER BY
RESIDENTS  - FUTURE LAND USE CONDITIONS

EXPOSURE  PARAMETERS FOR  INHALATION OF  VOLATILES
FROM  SHOWERING BY RESIDENTS  - FUTURE  LAND  USE
CONDITIONS

SUMMARY OF POTENTIAL HEALTH RISKS - FUTURE LAND USE
CONDITIONS

COST SUMMARY - ALTERNATIVE 3 - THE SELECTED REMEDY

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                 SUMMARY OF FINAL REMEDIAL ACTION
                        GROUNDWATER REMEDY

                  MUSKEGO SANITARY LANDFILL SITE
                        MUSKEGO,  WISCONSIN
I.  SITE NAME AND LOCATION

The Muskego Sanitary Landfill Superfund site occupies approximately
56 acres north of State Highway 24  (Janesville Road), and east of
Crowbar Road in  the City of Muskego,  Waukesha County, Wisconsin.
The site is located  in Southeastern Wisconsin approximately fifteen
miles  southwest  of  the City of  Milwaukee (see Figure  0) .   More
specifically the site is southwest of the urbanized portions of the
City of Muskego  by  roughly  three  miles.   The  Site includes three
areas known as the  "Old Fill Area", the "Southeast Fill Area" and
the  "Non-Contiguous Fill Area"  (see  Figure  1) .   The  site  also
includes wastewater ponds associated with a former rendering plant
complex (the "Anamax plant").   Portions of the property associated
with the Anamax  plant  are also included  in the Old and Southeast
Fill Area boundaries.   Directly north of the site is the Stoneridge
Landfill,  a closed  and covered solid  waste landfill,  that is not
part of the Superfund  site.  Land use to the  west of the site is
for sand and gravel excavation.   To the  south,  east and north of
the  site,   the   land  use is   a  combination  of residential  and
agricultural.  The area surrounding the Site is semi-rural, but is
zoned to permit  further development in the future.  Several homes
and businesses are_in the vicinity of the property,  and many were
once served by individual private water supply wells.  In the late
1980s, city water mains  were extended into the area  and several
homes  and  businesses  were connected.   Currently,  two residences
southeast  of the site are not connected  to public  water.   These
residences are indicated in Figure 1.

The Muskego Sanitary  Landfill  Site is situated on unconsolidated
deposits that are up to 300  feet thick and are generally comprised
of  glacial  till,  outwash,   and  lacustrine  deposits.     Site
investigative information and private  well boring logs show layers

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of fine-grained material  (till and lacustrine deposits) south and
east of  the site to  depths of about  70 to 200  feet  and coarse
grained material (outwash) below the till to depths of about 200 to
300 feet below land surface.

There  are  three  principal  sources  of  groundwater in Waukesha
County.   In order of  depth below  the  land surface they are:  sand
and gravel  within the  glacial drift,  Niagara dolomite,  and an
underlying  sandstone.   In the Muskego  area,  a  majority  of the
private wells are finished in the thick sand and  gravel deposits.
The water table for this shallow aquifer is approximately 20 to 40
feet deep and has produced yields  as  high as 2,000 gal/min.   The
depth  of  the  upper  glacial   drift   is about   300  feet  which
corresponds   to  the   aquifer  thickness.     The   groundwater
classification for this aquifer is Class IIA  (i.e., is used for
human consumption purposes and is not restricted).

In the Muskego area,  groundwater  flow in the water table shallow
aquifer is  generally in an easterly  to southeasterly  direction.
This is similar to the groundwater flow at the site, which has two
flow paths.   The first is in a north to south direction under the
eastern portion of  the Old Fill  Area where the  basal  clay  unit
separates the sand and gravel unit from the landfill.  The second
flow path is  generally to the southeast under  the Southeast and
Non-Contiguous Fill  Areas.  These  flowpaths are  separated  by  a
groundwater divide that was created by the advancement  of the Oak
Creek Till formation from the east.  A sand and gravel seam to the
southeast is  separated  from the larger outwash to the  south and
west of the site by the more impermeable clay layer.

The site is located within the Fox River watershed, just south of
a local surface divide.   There  are numerous  wetlands in the  area
and the  closest off  site intermittent  stream is  located  about
three-quarters of a mile  to the southeast.   None  of the wetlands
are located, within the  site boundaries.   Surface  drainage at the
site is divided between flow to the wetlands and  the intermittent
stream to the southeast.   Surface water runoff  from the Old Fill
Area is to the ditch along Crowbar Road or to the southeast through
a small swale.  The western half  of the Southeast Fill Area  also
drains to this swale which eventually discharges to a small wetland
north  of  an abandoned  railroad right-of-way.    Runoff from the
neighboring  Anamax  property,  the   Non-Contiguous Fill  Area,
Stoneridge Landfill,  and  the  eastern  half of the Southeast  Fill
Area is toward the ditch along  the service road to a small wetland
southeast of the site and then through a culvert under Highway 24
to a  larger wetland.   The site is located  within the  100  year
floodplain.

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II.  SITE HISTORY AMD ENFORCEMENT ACTIVITIES

A.  Site History
The 38-acre  Old Fill Area accepted material  from the mid-1950s
until 1977.  An unknown amount of waste  oils, paint products, and
other wastes  were deposited  into  the Old  Fill  Area during this
time.    The  Southeast  Fill  Area  which  covers  about  16 acres,
accepted only municipal  wastes  during its operation from 1977 to
1981.   The Non-Contiguous  Fill Area includes a drum trench, north
and south refuse  trenches, and  an L-shaped fill 'area.  This Non-
Contiguous Fill Area occupies approximately 4.2 acres northeast of
the Old  Fill Area.   Based on information  from  workers employed
during  operation  of the  landfill,   the L-shaped  Fill  Area  is
expected to contain waste  similar to that in the Old Fill Area.

In response to deteriorating  water quality at on-site groundwater
monitoring wells, sampling of off site private water supply wells
was conducted  in 1982  and  1984  by  the  site  operator,  Waste
Management of Wisconsin, Inc. (WMWI) , and Wisconsin Department of
Natural Resources (WDNR).  The results of these analyses indicated
that several  of the  private wells may  have been  impacted  by a
source of contamination,  which could have been the landfill and/or
the Anamax wastewater lagoons.  The results  were based on elevated
indicator parameters.    The   test  for  indicator parameters  is a
preliminary  test   completed to   show  signs   of  groundwater
contamination.  In 1986 public water  was  extended to this area and
private wells in the area were connected  to  this  supply.  The site
was evaluated  and  ranked by  the  United  States  Environmental
Protection Agency (U.S.  EPA)  and placed on the National Priorities
List (NPL)  on September 18, 1985.

In 1985,  a  partial methane extraction system was' installed by WMWI
along the western portion of the Old Fill  Area to alleviate methane
gas migration that was noted  at the site.    The extracted gas is
destroyed through flaring.

B.  Response Actions
During preparation of a portion  of  the Phase I Stoneridge Landfill
area called Module  III,  which is due east  of  the Non-Contiguous
Fill Area,  buried drums were  discovered  in  a pit.   The drums and
contaminated soils  were  excavated by Chemical  Waste Management,
Inc.,  under the supervision of WDNR,. and transported to the Adams
Center Landfill in Ft. Wayne,  Indiana. Also liquid wastes from the
excavation and  drums were transported to the SCA Incinerator in
Chicago,  Illinois.   The contaminated soils were excavated until
contaminant concentrations in subsequent soil  samples were below
action levels established  by  WDNR.

During the  Remedial Investigation (RI), a trench was discovered in
a portion of the Non-Contiguous  Fill Area that  contained a large
concentration of 55-gallon drums.  The boundary of this Drum Trench
area was  further  defined using a magnetometer  metal  detector.

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Through  a Unilateral Administrative  Order issued  on January 4,
1991, U.S.  EPA ordered WMWI to  remove  the drums and surrounding
contaminated soils.  WMWI proceeded to conduct this removal under
U.S. EPA's  supervision.   Excavation of the drum trench began in
April 1991  and was completed in May 1991.  A total of 989 drums
were  excavated  along  with  approximately 2,500  cubic yards  of
surrounding contaminated soil.   The soils  were excavated down to a
depth of approximately 25 feet below the original  surface elevation
until groundwater was encountered.

The drum trench was re-filled to a grade that allowed drainage away
from the area.   No final soil clean-up levels were established for
this removal action since the excavation  reached groundwater in
portions  of the trench.   Therefore a  majority  of the soil  was
removed.  Soil  samples were taken in the remaining areas above the
water table at  the base of  the  trench and contamination  was found.
This remaining  contamination was addressed in the Interim Action
Source Control Operable Unit (SCOU) Record of Decision  (ROD).

Below  is   a   list   of  contaminants   that were  found  from  a
representative sample of liquid collected from excavated drums on
the  staging pad  on April  17,  1991.    The list below  shows
contaminants that  were above  detection  limits.    The  detection
limits   for all  contaminants  were  elevated   due   to  sample
concentrations.

Benzene             Chloroform          Ethyl Benzene
Toluene             Trichloroethene     Methylene Chloride

Some of the other contaminants  that were sampled  for and found but
not quantified because of elevated detection limits  include; vinyl
chloride,   tetrachloroethene,    1,2-dichloroethane,   and   1,1-
dichloroethene.   Contaminants  found within  the  drum  trench  are
contaminants that are present in monitoring wells at the Site.

The liquids from the excavated drums were separated,  bulked,  and
disposed  of   through  either   a  fuels   blending  program   or
incineration.  The liquids used in the blending program were sent
was Solvent Resource Recovery facility in West Carrolton, Ohio and
incinerated liquids were processed at Aptus Environmental Services
in Coffeyville, Kansas.  A majority of the soils  were disposed of
in a hazardous  waste cell unit at  the  Calumet Industrial Design
Landfill  (CID)  in Calumet  City, IL.  Solids remaining in the drums
were tested, bulked and accepted at a  fuels blending facility in
April of 1992 for repackaging.  The solids totaled approximately 15
cubic  yards and were  then sent  to  a  facility  in  Texas  for
incineration.  The disposal procedures occurred from October 1991
through April 1992.

C.  Remedial Investigation/Feasibility Study  (RI/FSl
On September 17, 1987, WMWI signed an Administrative Order on

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Consent     with    U.S.     EPA    to    conduct    a    Remedial
Investigation/Feasibility Study  (RI/FS) for the site.   The purpose
of  the  RI  was  to identify  sources  of  contamination and to
characterize the  contamination at  the  site.  The RI was  finalized
on  November 4,  1992.    The  Final RI  includes a  Baseline  Risk
Assessment  which was  conducted  to characterize  the  current and
potential threat to public health and the environment  at  the  site.
To focus and expedite clean-up of the site, the project was divided
into two operable units - the Source Control Operable  Unit  (SCOU)
and the Groundwater Operable Unit (GWOU) or Final Remedy.  The SCOU
focused on  removing and  containing remaining contaminants in on-
site soils  to  minimize the  further  spread of contamination; the
GWOU focuses on cleaning up contamination  in  groundwater at the
site.

A Source Control Operable Unit FS  was prepared in September  1991.
That FS provided a detailed analysis  of alternatives evaluated for
the interim action SCOU.  The SCOU remedy proceeded as an interim
remedial action even before the Baseline  Risk Assessment and RI
were completed.   The FS  for the  GWOU was prepared in March  1993.
The  alternatives  developed  in  this  FS  are  presented in the
Description of Alternatives, Section VII.   Together with  the  SCOU,
this GWOU constitutes the Final Remedy for the Site.

D.   Remedial Design/Remedial Action
In December  1992  a Record of Decision was  signed for the Source
Control Operable  Unit  (SCOU)  action at  the  site.    This action
includes the design and installation of a 2  foot clay cap over the
waste  areas,  expanding the  current  leachate  and gas extraction
system over the entire site,  constructing  an In-situ Soil Vapor
Extraction  (ISVE)  system  in the  area of  the drum  removal and
groundwater monitoring.

On December 9,  1991, U.S.  EPA issued a Unilateral Administrative
Order  requiring  46  identified  potentially .. responsible parties
(PRPs)  to perform the SCOU remedy.  Those PRPs included Carl Wauer
(the site owner),  WMWI  (the site operator for a period of  time when
hazardous  substances were  disposed  of) ,  and  44 generators of
hazardous substances disposed of  at the site. The vast  majority of
these  parties  complied with the  order and implemented  the SCOU
remedy.

The Remedial Design for this SCOU work was completed and approved
in October 1993 and work began that same month.  The entire project
was completed by October 1994 with minor field modifications that
included  the   removal   of  an  underground   storage  tank  and
approximately fifteen buried drums.  Prior to the construction of
the clay cap, several buildings from the Anamax Rendering  facility,
which has been  acquired by  WMWI,  were demolished with the debris
consolidated on site.  Full-time operation of the dual extraction
wells  for leachate  and  landfill gas  began  in November  1994.
Groundwater monitoring under the  Interim  Groundwater Monitoring

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Plan (IGMP) began in April  1994 and will continue until a long-term
monitoring plan is designed and approved as part of the Groundwater
Remedy described  in  this ROD.

III.  COMMUNITY PARTICIPATION

The U.S. EPA  released its  Proposed Plan for the final remedy for
the Site  in October  1994,  and  has made it  available  for public
review and  comment.   The  Proposed  Plan  and supporting documents
have been  made available at the  information repositories at the
U.S. EPA  Region V offices,  the  Muskego Public  Library,  and the
Muskego City Hall.  U.S. EPA has been placing relevant information
in these repositories since 1987.   Notice  of the availability of
the Proposed  Plan was included in  advertisements in the Muskego
Sun. Hales  Corners Hub, and Waukesha  Freeman  in September 1994.
Press releases were  also sent to  local media.   Before reaching a
final decision on how the site contamination would be addressed for
this action, U.S. EPA held a public meeting on October 17, 1994 at
the Muskego City  Hall.  At this  meeting, representatives of U.S.
EPA and  WDNR  answered questions about  the proposed remedy and
accepted formal comments from the public on the Proposed Plan and
remedial alternatives.   U.S EPA also accepted  written  comments
during the comment period,  which  originally ran from October 2, to
November 2, 1994.  A request for extension of the comment period
was submitted on November 2nd and accepted.  The 30  day extension
moved the end of the public comment  period  to December 2,  1994.  A
response to all comments received during  the public comment period
is contained  in  the  Responsiveness  Summary,  which is attached to
this the ROD.

Other  community  relations  activities  were  associated with  the
Source Control Operable Unit  (SCOU) Proposed Plan and the RI/FS.
The first comment period was held from August 28 to  September 27,
1987 concerning  the signing of  the RI/FS  consent order.   Press
releases announcing this comment period were sent to local media.
A  community  relations plan  was  finalized in  early 1988.    A
"kickoff" meeting to discuss the initiation of the RI was held at
the Muskego City Hall on Aug. 25, 1988.  Advertisements and press
releases were sent to local media.   A fact  sheet was developed and
sent to everyone on the U.S. EPA's mailing list.

In June 1991,  a press release concerning U.S.  EPA's  drum removal
project was  issued and a  fact  sheet  was  developed and  sent to
everyone on the mailing list.  This fact sheet served as a notice
of activities  associated with the drum removal  and  as an overall
update on site activities.

On December 12, 1991, U.S. EPA held a public meeting for the SCOU
Proposed  Plan  at  the Muskego  City  Hall.   At  this  meeting,
representatives for U.S. EPA and WDNR answered questions about the
proposed remedy and accepted formal comments from the public.  U.S
EPA also accepted written comments during the comment period, which

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ran from November 18, to December 18, 1991.  The SCOU ROD contained
a  response to  all comments  received  during  the public  comment
period.

Fact Sheets describing actions at the  Site were  released  in  July
1993 and June 1994.   These annual informational updates  were  sent
to community representatives, concerned citizens,  and local media.
These Fact Sheets have served as the primary sources of information
for the community  since  the  comment period  for the  SCOU  ROD.  The
objectives of these fact sheets were to provide information on the
SCOU construction activities,  to describe progress towards the
Final Remedy,  and to serve as a reminder to local residents  of  whom
they may contact to answer questions regarding the  site.

IV.  SCOPE OF GROUNDWATER REMEDIAL ACTION

The Groundwater Operable Unit (GWOU)  is intended to be  the final
response action for  this site.   The action will  directly  address
on-site groundwater contamination concerns  and control the threat
to  off-site  wells by  containing  and  remediating  contaminated
groundwater.  These concerns  arise both from existing contamination
and from further contamination that may migrate from source areas
on-site.

As with many Superfund sites, the problems at the  Muskego Sanitary
Landfill  are  complex.    Early site characterization activities
conducted as  part  of the RI  identified sources of  contamination
that could  be addressed before  full  characterization activities
were complete.   Therefore,  to accelerate the  remediation  of the
sources of  contamination,   U.S. EPA,  in consultation with WDNR,
organized the work into  two operable units  (OUs).

The  first  operable   unit,   the  Interim Action  SCOU,   addressed
contamination movement into the groundwater  and soils from  sources
within the Old, Southeast,  and Non-Contiguous  Fill Areas.   These
areas pose a threat to human health  and the  environment because of
the risks  from possible ingestion of,  or dermal  contact with,
contaminated  soils located  there or  possible ingestion  of, or
dermal contact with, contaminated groundwater at private residences
downgradient of the  Site.   Based on sampling  by  the U.S.  EPA in
August 1991,  there.were  no  current impacts of  Volatile  Organic
Compounds  (VOCs)   at  private wells  downgradient  of the Site.
However, the threat of future impacts to private well exists since
downgradient monitoring wells have shown contamination.

The first purpose  of  the SCOU response was  to prevent current or
future exposure to the contaminated soils and to reduce contaminant
migration into the groundwater that is a current source of drinking
water for local residents.  The second purpose of this response was
to prevent current or future exposure  to landfill gas containing
explosive and potentially toxic  contaminants  and  to reduce the
migration of landfill gasses  to adjacent soils and structures.

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The combination of this action along with the previous actions is
intended to address the entire site with respect to the current and
potential future threats to human health identified in the RI, FS,
and site Baseline Risk Assessment.

V.   SITE CHARACTERISTICS

A.   Geology and Hvdroqeology
The site is  located in an area of thick glacial drift overlying
Niagara dolomite.   The drift  thickness  varies from approximately
300 feet on  the east edge of the site  to 50  feet  at a location-
about 2,000  feet south of  the  site.    The  site  overlies  a deep
valley in the bedrock that is part of the Troy Valley which trends
to the east with a steep bedrock slope rising to the south.

The valley in the bedrock beneath the site is filled with sediments
consisting of sand  and gravel with a  cover of  glacial  till.   In
general, fine-grained material (till and  lacustrine deposits) south
and east of the site extend to .depths of approximately 70 to 200
feet.  Below  the till is coarse material  (outwash)  which extends to
depths of about 200 to 300 feet  below  land surface.

At  the  northern portion  of  the site  is the  Upper New Berlin
Formation which  is a till  deposit  forming an  east-west tending
moraine.  The New Berlin Formation contains two principal members,
a lower sand and gravel unit and an upper till unit.  The western
portion of the site consists of  the lower outwash sand and gravel
unit that extends  southwest  from the  site toward the Fox River.
The upper unit is typically gravel,  sand, loam till that averages
about 58 percent sand,  29 percent silt,  and 13 percent clay.

The sand and gravel deposits are present east of Crowbar Road and
south of the  landfill access road, beneath the western edge of the
site,  and extend east to the boundary  of the basal clay under the
Old Fill Area (Figure 2).

Above the New Berlin formation  is the Oak Creek Formation which
consists of a much finer textured composition of fine-grained till,
lacustrine clay, silt,  and sand.  This formation on an average
consists of approximately an 85 percent clay-silt composition.  The
western limit of the Oak Creek Formation is the Valparaiso Moraine
and ends within the Old Fill Area. . The western extent of the clay
till  and  other low permeability  material  is  vertically  and
horizontally  irregular.    As  a  result, its  extent  cannot  be
accurately defined,  nor can an edge of low permeability material of
constant  thickness  be  mapped   with   an  acceptable  degree  of
certainty.    The  approximate  Basal Layer Boundary is  outlined in
Figure 2.

The glacial sediments in the area are underlain by the Silurian-
aged Niagara  dolomite, at depths between 250  to 350 feet below land
surface.   The  Niagara  dolomite  is  sequentially  underlain  by

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Maquoketa shale, dolomites,  sandstones, and igneous and metamorphic
rocks.   The Maquoketa  shale in  the  Site area  is documented by
private well logs which indicate  there is about  200  feet  of  shale
below the Niagara Dolomite.

The groundwater flow  in the site area varies in direction due to
the complex geological features.  The  general groundwater  flow for
the region is from the north to the south.   Within unconsolidated
areas located at the  northern  and western edges of the site, the
groundwater moves in a southerly direction.  However the  geology by
the Southeast  and Old Fill Areas consists  of  consolidated  clay
layers.  Therefore perched  groundwater conditions exist  in  these
areas.   Groundwater  flows radially in all  directions from  these
areas.  (Figure  3)   Groundwater from  the  northern portion of the
site  near  the  old rendering  plant  lagoons is  split  by  a low
groundwater divide in the  sand and gravel  deposits.  One flow path
moves generally along a Southeast route.that is directed beneath
the Non-Contiguous  Fill  Area,  the Southeast  Fill Area  and the
Anamax plant.  The other flow path moves generally along  a  southern
route that is directed under the Old  Fill Area.

Similar to the groundwater flow, the  water table in the site  area
also varies due to complex geological  features.   Since the site is
located at  the  end of two  glacial advancements,  the Berlin and
Oakcreek formations,  consolidated clay layers are  intermixed  with
unconsolidated sand and gravel.   Since the permeability  of these
soils varies so  does the water table.  Therefore the water  table at
the site is from 20 to 40 feet deep.  In areas where groundwater is
perched or leachate is held  within the basal  layer  the water table
is 20 to 30 feet deep.

Presently,  the main aquifer  in the sand and gravel unit is  used for
private water supply downgradient of  the site in only two private
residences.  Public water was  provided to the  Site  area  in  1986
along Janesvilie Road to  the South and Hillendale Avenue to the
east.   The  municipal well  system is located a few miles east of the
site and is not near,  nor is it affected,  by the site.

Hydraulic conductivity varies throughout the  site depending on the
soil type.  Within the clay till, the hydraulic conductivity ranges
from 1.6 x 10'6  centimeters  per second (cm/s) to 5.1  x  10'* cm/a.
However, the hydraulic conductivity of the sand and gravel  deposits
is much higher,  ranging from 3.9 x 10'2 cm/s  to 1.2 x  10'3  cm/s.

B. Nature and Extent of Contamination
The RI sampling  of groundwater  was  conducted at monitoring wells
and  private  wells  throughout  the  site.    Since  April   1994
groundwater  monitoring has been  conducted under   the  Interim
Groundwater Monitoring Plan  (IGMP) which will continue until a  long
term monitoring plan is  implemented  under  this ROD.  The  IGMP
includes semi-annual  sampling  of volatiles, serai-volatiles and
inorganics.  Quarterly sampling  for indicator  parameters  is  also

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performed tinder the IGMP.  During the IGMP several monitoring wells
throughout  the  site were abandoned due to poor  well  construction
quality, SCOU remedial activities, or various factors.  Since this
work was completed after this FS was drafted these wells are not
reflected as abandoned in  the tables and  figures for  this ROD but
a description of the  IGMP  has been included  as Attachment A.

Groundwater
Groundwater is  the  main  pathway  of concern   for  contaminant
migration at  the site.  As* mentioned above, there  are two main
groundwater flow paths.  The first one,  known as  the Southern flow
path, runs from the northern section of the site under the Old Fill
Area and  continues to the south.   The second  or Southeast flow
path, also  moves from the northern  portion of  the  Site,  but is
diverted to the southeast and  flows beneath the Southeast Fill
Area,  the  Non-Contiguous   Fill  Area  and Anamax property.   In
addition, conditions exist  where  leachate  accumulates  in  areas
above these flow paths  in  perched or elevated conditions  (Figure
3) .  A  summary of  the  organic group results for all monitoring
wells at the site is  listed in Table 1.

Southern Flow Path  - The Southern Flow Path is potentially affected
by  the  former  rendering  plant  lagoons,  and the  Old  and Non-
Contiguous Fill Areas. Two rounds of  groundwater  sampling occurred
at 12 downgradient wells at  seven different  locations.  A summary
of U.S.  EPA MCL and WDNR NR 140 exceedances is provided in Table 2:
locations of the monitoring wells are shown  in Figure 4.

Organic contamination located in  the Southern Flow Path includes
BETX (benzene,  ethylbenzene, toluene, xylene), chlorinated ethene,
and chlorinated ethane groups.  Individual chemical concentrations
and well locations are listed below.

Constituent              Concentration       Well Location

Benzene                     1 ug/L                 135A
Toluene                     3 ug/L                 123B
Ethylbenzene                3 ug/L                 123B
Xylene                     1-13 ug/L               1 2 3 B ,    9 6 P
Tetrachloroethene           1 ug/L                 123B
Trichloroethene            1-3 ug/L         123B,  135B, 138A
1,2-Dichloroethene         1-8 ug/L        135A-B,    137A-B,    96
Chloroethane                2 ug/L                 135A
1,2-Dichloroethane          2 ug/L                 135A,  137A
1,1-Dichloroethane         1-5 ug/L   135A-B, 137A-B,  95P, 96

Semi-volatile compounds  and pesticides/PCBs  were not detected in
the Round I groundwater  samples  collected from  the Southern Flow
Path.   Therefore,  Round 2 samples were  not analyzed  for these
parameters.
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Groundwater monitoring wells were also sampled for Target Analyte
List  (TAL)  metals  and cyanide,  and general groundwater  quality
indicators.     These  analyses  were  used   to  assess   chemical
concentration trends within the aquifer to aid in the determination
of groundwater  flow patterns,  and contaminant fate and migration.

There are seven TAL constituents that were detected in one or more
monitoring well, sample(s)  along the Southern or Southeastern Flow
Paths at levels higher than those detected in the background wells
E80 and TW75.  All of  these seven were detected along the  Southern
Flow Path at various  wells.   The constituents were as follows-:

*    Arsenic         * Lead         * Zinc
*    Barium          * Manganese
*    Chromium        * Nickel

Southeast Flow  Path - The Southeast Flow Path  which  diverts from
the  Southern Flow  Path in  the northern  area of  the site, was
characterized using 11 monitoring wells at  six locations.  The.
organic compound sampling  from these wells are summarized  in Table
l; locations of the monitoring wells are shown  in Ficrure  5.

There are four  organic contaminant groups that were  detected on-
site along  the Southeast  Flow  Path.   These groups  are  BETXs ,
chlorinated   ethenes,   chlorinated  ethanes,   and   phthalates.
Individual concentrations and well locations  are listed below. One
organic contaminant, vinyl chloride, was found off-site, at levels
in exceedance  of Federal  Maximum  Contaminant  Levels (MCLs) and
state NR 140 Enforcement Standards  (ESs) as shown in Table 3.  The
vinyl  chloride  contamination   was  found  during   groundwater
monitoring southeast  of the  Site at Well P64C.

Constituent              Concentration        Well Location
Benzene                    1 ug/L                 92A
Xylene                     1 ug/L                 92P
Trichloroethene            2-3  ug/L               92A
1,2-Dichloroethene         2-3  ug/L               92A
Vinyl Chloride             5-7  ug/L               64C
1,2-Dichloroethane         2 ug/L                 92A
1,1-Dichloroethane         6-7  ug/L               92A

Additional organic" compounds detected  in  this  area  include 1,2-
dichloropropane from  monitoring well E92A at a  concentration of 2
ug/L (Rounds 1  and  2) ; and methylene chloride  (a common/probable
laboratory contaminant) , at well TW62 at a concentration of 2 ug/L
(Round 1 only).

Phthalates were detected in  one groundwater  sample from this area
during Round 1  (E92-3 ug/L), and two samples from Round 2  (E94-4
ug/L, and TW62-3 ug/L).  Constituent compounds detected were di-n-
octyl phthalate and bis  (2-ethylhexyl)phthalate.


                                11

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As with the Southern Flow Path, pesticides/PCBs were not detected
in  Round   1   groundwater   samples  collected  from  this  area.
Therefore, Round 2 samples  were not analyzed for these parameters.

There are five TAL constituents that were detected in one or more
monitoring  well  sample(s)   along  the  Southeastern Flow  Path at
levels higher than those detected in the background wells E80 and
TW75.  These constituents are as follows:

*    Arsenic        * Zinc
*    Barium         * Manganese
*    Nickel

Other areas - The Southern and Southeast Flow Paths described above
affect well locations primarily downgradient from the site as shown
in Figures 4 and 5.

Monitoring wells are also  located  in the Non-Contiguous Fill and
Anamax plant areas as well  as  along the northern extent of the Old
Fill Area (Figures 6 and  7) .   The highest concentration of organic
contamination for the site was found at wells in the Non-Contiguous
Fill Area.  Specifically, monitoring well E136, located in the Non-
Contiguous Fill Area, was contaminated with  several VOCs at levels
in exceedance of MCLs and ESs as shown in Table 4.

Contaminant groups  that  were detected within the Non-Contiguous
Fill Area, Anamax plant and northern  boundary areas include BETXs,
chlorinated ethenes, chlorinated  ethanes,  ketones,  phenols,  and
polycyclic aromatic hydrocarbons (PAHs).  Some  of the individual
concentrations and well locations are listed below.

Constituent              Concentration       Well Location
Benzene                    1-21 ug/L         10 OA, 102A, 104
                                             97P, TW74R, 87
Toluene                  8-12,000 ug/L           102A, 136
Ethylbenzene             270-7,300 ug/L          102A, 136
Xylene                   5-39,000 ug/L           102A, 136
Tetrachloroethene           3 ug/L                  17R
Trichloroethene            1-7 ug/L     87,  100A, 104, TW74R
1,.2-Dichloroethene         1-12 ug/L        100A, 102A, 104
                                              TW74R, 87
1,2-Dichloroethane         3-9 ug/L            102A, 87
l,l^Dichloroethane        '3-8 ug/L         100A, 102A, 104
                                                87, 97P
Chloroethane                8 ug/L                 97P
2-Butanone               9-2,400 ug/L           136, TW74R

Two additional volatile compounds were detected in wells along the
northern  boundary of  the  Old  Fill  Area.   These  included 1,2-
dichloropropane at 5 ug/L from well E17R, and tetrahydrofuran from
E48 at 41 ug/L.  A summary of U.S.  EPA MCL and WDNR NR 140


                                12

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exceedances in groundwater along the northern wells is provided in
Table 5.

Individual semi-volatile constituent compounds included phenol (870
ug/L), 4-methylphenol (2,100 ug/L),  and naphthalene (360 ug/L)  from
well E136; 4-methylphenol  (5 ug/L)  and benzoic acid  (6  ug/L)  from
well TW74R; and 2,4-dimethylphenol (2 ug/L) from well E102A. Along
the northern boundary wells, only di-n-butyl phthalate was detected
from well 90 at 2 ug/L.

Pesticides/PCBs were  not detected in Round 1 groundwater samples
collected from  these  areas.   Therefore,  Round 2 samples  were  not
analyzed for these parameters.

There  are  TAL constituents  that   were  found  in  one  or more
monitoring well sample(s)  in these  areas  at  levels greater than
levels found in background wells E80 and TW75.  These constituents
are as follows:

*  Arsenic     *  Chromium      *  Lead      *  Manganese

Private Wells - Many of  the private  wells near the site have been
sampled several times during the history of operation at the site.
Sampling during pre-RI/FS activities by Warzyn, WMWI's contractor,
on May  3,  1991 and by  U.S.  EPA on  August  28,  1991,  showed that
nearby water  supplies were not impacted,  at  that  time, by site-
related contaminants.   Locations  of the nearby private wells  are
shown in Figure 8.  All  private well sampling results are included
in Appendix K of the RI.

Soil
The results  of  the soil and sediment  sampling  were explained in
detail  in the  SCOU  ROD,  which focused  on  soil  and  sediment
contamination.  The primary constituents of concern in soil are:
benzene, toluene,  xylene, ketones, phenols and polynuclear aromatic
hydrocarbons  (PAHs).

Air
The RI did not generate  useable data on ambient air, leachate head
well and gas vent  vapor emissions.   The requirement for  landfill
gas collection  and treatment,  NR 506.08 Wisconsin Administrative
Code (WAC), has been addressed by implementation of a landfill  gas
management system as part of the SCOU  remedy.  This system should
control any releases to  the air from the waste material  and there
are no further expected  sources of air contamination from the site.
Air monitoring  and treatment  may  be  required depending on  the
installation  of groundwater  treatment  systems.   Air  emissions
resulting from a groundwater treatment  system would be regulated by
NR 445, Wis. Adm.  Code.   At this time treatment of air emissions
from a groundwater  treatment system, such as an air stripper, is
not expected to be necessary.


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Surface Water
Topographic highs  in  the vicinity of the site consist of a large
end moraine north and northeast,  and two  topographic highs created
by  the Stoneridge  facility and  the Southeast  Fill  Area.   The
natural  topographic high  acts  as a  surface  water divide.   The
majority of the runoff from the  site flows  to  the southeast to two
wetland  areas  and  to  an  intermittent stream.   Runoff  from the
western portion of  the Old Fill Area flows to Crowbar Road on the
west end of the site.

Surface water is not a significant contaminant  migration pathway at
the site due to the lack of permanent surface water features and
the presence  of newly placed  cover soils, which  will  generally
prevent contact of  surface-water runoff with refuse.  Sampling of
surface water was not conducted during the RI.

VI.  SUMMARY OF SITE RISKS

The Comprehensive Environmental Response Compensation and Liability
Act (CERCLA) , 42  U.S.C.  §§  9601  et seq..  requires that U.S. EPA
protect human health and the environment from current and potential
exposure to releases of hazardous substances at or from the site.
As part of the  RI,  a Baseline Risk Assessment  is required in order
to assess the current and potential future  risks by the Site.  The
baseline risk assessment  determines  whether contamination at the
landfill could pose an unacceptable health risk or environmental
risk in the absence of any remedial action.  Potential threats to
public health are estimated by making assumptions about the manner,
frequency and length  of  time a person could  be  exposed  to site-
related contaminants.

This Baseline Risk Assessment was prepared in a manner consistent
with U.S. EPA policy, as  expressed in "Role of the Baseline Risk
Assessment in Superfund  Remedy Selection Decisions,"  dated April
22, 1991.  The quantitative risk assessment examined contaminants
detected  in groundwater,  leachate,  and soils  during the  field
investigation phase of the RI.   These contaminants were evaluated
with  respect  to  their carcinogenicity,   toxicity, and  possible
exposure pathways from and at the site.

A.  Identification of Chemicals of Potential Concern
The purpose of  selecting chemicals of potential concern  for the
risk assessment is to identify those  chemicals present at the site
most likely to be of concern to human health and the environment.
Since the Final Remedy addresses  groundwater,  the  following is a
list of contaminants detected in soil and groundwater at and near
the site.   The  following codes are used to identify  the  various
groundwater well location areas around the site where contamination
was located.
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     Non-contiguous Fill
     Southeast Flow Path
     Southern Flow Path
     Northern Boundary
Organ!cs:

Benzene  -  NC,SE,SO,NB
2-Butanone  -  NC
Chloroform  -  NC
Di-n-butylphtalate - NB
1,2-Dichloroethane - NC,SE,SO,NB
1,2-Dichloropropane - SE,SO,NB
bis(2-Ethylhexyl)phthalate - SE
Ethylbenzene - NC,SO
Naphthalene - NC
Pyrene - SO
Tetrachloroethene - NB
Toluene -  NC
Vinyl Chloride - SE
Area/Former Anamax Facility
NC
SE
SO
NB
          Benzoic Acid  - NC
          Chloroethane  - NC,SO,
          Di-n-octyl Phthalate - SE
          1,1-Dichloroethane - NC,SE,SO,NB
          1,2 -Dichloroethene - NC, SE, SO, NB
          2,4-Dimethylphenol - NC
          Dichlorofluoromethane - NC,SE,SO
          4-Methylphenol  - NC
          Phenol - NC
          Pentachlorophenol - SO
          Tetrahydrofuran - NB
          Trichloroethene - NC,SE,SO,NB
          Xylenes (total) - NC, SE, SO
Inorganics: %

Aluminum - NC
Barium - NC,SO,SE,NB
Calcium - NC,SE,SO,NB
Chromium - NC,SO
Copper - NC,SO
Lead - NC,SO,SE,NB
Manganese - NC,SO,SE,NB
Potassium - SE,SO
Selenium - SE,SO
Sulfate - SE
Vanadium - NC
          Arsenic - NC,SE,SO,NB
          Cadmium - NC
          Chloride - NC,SE,SO,NB
          Cobalt - NC,SE,SO,NB
          Iron - NC,SE,SO,NB
          Magnesium - NC
          Nickel - NC,SE,SO,NB
          Silver - NC,NB
          Sodium - SE,SO,NB
          Thallium - SO
          Zinc - NC,SE,SO
Of the  chemicals in groundwater,  those which  exceeded the Safe
Drinking Water Act or  state  NR 140 WAC groundwater standards are
shown in  Tables 2,  3  and 4.   This  Table compares  the maximum
groundwater concentrations in the immediate source areas with the
MCLs, state  NR  140  Enforcement  Standards (ESs)  and  Preventive
Action Limits (PALs)  .

Based on  toxicological studies,  benzene  and vinyl  chloride are
classified  as  U.S.   EPA  Group  A -  human  carcinogens;  while
trichloroethene,   tetrachloroethene   and   pentachlorophenol  are
classified as Group  B2 -  probable human carcinogens.   Typically,
exceedances of  drinking water  standards  (such as the MCLs)  may
justify the need for  remedial action.  The  Baseline Risk Assessment
reinforces the existence  of  a  potential threat to public health,
welfare or the  environment.   Actual  or threatened  releases of
hazardous  substances   from  this  site,   if   not  addressed  by
                                15

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implementing the response action selected in this ROD, may present
an imminent and substantial endangerment to public health,  welfare,
or the environment.

B.  Exposure Assessment
The objective of an exposure assessment is to estimate the type and
magnitude of exposures  to constituents of potential concern that
are  present or are  emanating  from  the  site.    There  are two
scenarios to consider for an exposure assessment.  The first is  a
current use scenario and the  second is a  reasonable future use
scenario.  This assessment will be focused on groundwater since the
SCOU has  already limited exposures through  all  other media.  In
order to complete an exposure assessment the exposure  pathways must
be identified.   An  exposure pathway must include the following four
elements;  (1)  a source and mechanism of chemical release to the
environment,  (2)  a  transport  media  (e.g.  groundwater),  (3)  an
exposure  point,  and  finally,   (4)  an  exposure  route  such  as
ingestion or  inhalation at the  contact  point.   In  summary, the
exposure assessment is  a  review of how contamination may come in
contact with living organisms via groundwater.

Groundwater Pathways - Current uae scenario
Site-related chemicals  have been detected  in the sand and gravel
aquifer in the immediate area of the source areas.   The potential
exists for this contamination to move with groundwater flow toward
private residences.  However, at this time there are no currently
active residential wells on or nearby the site.  Two downgradient
private wells screened in the sand and gravel aquifer  are available
for non-potable uses.  These wells were included in the August 1991
sampling conducted by the U.S. EPA which did not detect any VOCs in
private water supplies.  One  of  these wells has since been sampled
as part of the  Interim Groundwater Monitoring Plan (IGMP) and also
has not shown any detections  of  VOCs.  There is no indication that
these wells were impacted by site-related chemicals, and therefore,
groundwater  was not  evaluated  under  a current use  scenario.
However, the IGMP did verify that contaminants are still present in
monitoring wells downgradient of the source areas.

Future use scenario
According  to  the  National  Contingency  Plan (NCP) ,   a  no-action
alternative must address  changes of  land use associated with the
site which  may result in exposure  and risk  to  the  chemicals of
potential  concern. •   Table  6   (4.2  in  Risk  Assessment of  RI)
summarizes  the exposure  pathway  analysis  for  future  site  use
conditions.  This  table  can also  be found  in Section  4  of the
Baseline Risk  Assessment of  the RI.   Since the SCOU  has  been
completed   the   only   direct  exposure  media   of  concern  are
groundwater.

Under  future-use  conditions,  the  assumption  was  made that  a
hypothetical well  would  be  constructed  on-site  or immediately
downgradient from the site in either of the two primary flow paths

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and  would  be used  for  water  consumption.    Therefore,   future
residents could be exposed via ingestion of site-related chemicals
from  drinking water and  inhalation of  volatile chemicals while
showering.  Dermal absorption is not being considered because it is
less  significant  than  the other two groundwater exposure  routes.
Cumulative  risk  is  driven primarily  by  potential  ingestion  of
groundwater and inhalation of shower water.  Therefore the addition
of the dermal absorption  scenario would  not impact the  cumulative
risk.   From  these  scenarios, assumptions  can  be made  so as  to
quantify the  risk scenarios.  These estimates and assumptions  are
provided in the Toxicity Assessment section of the risk assessment.

C.  Toxicity Assessment
The Toxicity Assessment explains contamination levels, risk levels
and potential carcinogenic effects for  contaminants of concern.
Risk  levels show the potential  for increased cancer effects based
on a  lifetime exposure of the contaminants known to cause  cancer.
Based on  U.S.  EPA  risk  assessment   guidance,  exposures   are
quantified  by estimating  the reasonable  maximum  exposure  (RME)
associated with the pathway of  concern.  An acceptable  risk range
for the U.S.  EPA  according to the NCP  is 10*4 to 10'6.   This means
a range of  increased cancer  frequency from one additional person
out of  10,000  to 1 out  of  1,000,000 people.   Risks  from non-
carcinogenic health hazards are based on a Hazard Index value.   The
Hazard Index value is calculated on the exposure  amount compared to
a Reference Dosage.  Reference Dosage guidelines  are established by
U.S. EPA.   Hazard  Index values greater than 1 indicate there may be
potential health  risks  associated with exposure to the chemicals
evaluated.

Ingestion of Groundwater
Drinking water exposures for a hypothetical future resident  located
on-site and  downgradient  from the site  were  evaluated.   Chronic
daily  intakes  were  calculated  for  residential drinking water
exposures using the RI  monitoring data  for  the Non-Contiguous Fill
Area,  Southeast Flow Path and Southern Flow Path data groupings.
The exposure parameters for this pathway are presented in  Table 7
(Table 4-16  in  BRA of  RI) .  Exposures were assumed  to  occur  350
days/year, with the residents  living  in the same  location from
birth to age 30 out of their 70-year expected lifetime.

The resulting Chronic  Daily Intake  (CDI)  levels for  chemicals
exhibiting   carcinogenic   effects   and  chemicals   exhibiting
noncarcinogenic effects  due  to ingestion of  groundwater were
calculated.  These values  were then taken and used to estimate  the
total future scenario risk presented in section D.

Inhalation While Showering
Inhalation exposures to volatile chemicals while  showering with
groundwater were calculated for hypothetical future residents.   The
exposure parameters for inhalation of volatiles from showering by
residents are  presented in Table B  (Table 4-20 in  BRA of RI)) .

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These  are standard  parameters  used by  U.S.  EPA  to assess  this
pathway.  These parameters include an exposure time of  17 minutes,
a frequency of exposure of 350 days/year, an  exposure  duration of
30 years, and an expected  lifetime of 70 years.  The exposure point
concentrations were  calculated  using a shower model described in
Appendix B of the RI.  The resulting risk from these calculations
is explained in the Risk  Characterization section below.

D.  Risk Characterization
The objective of this section of the assessment is to present and
evaluate  the  human  health risks   potentially  associated  with
ingestion of groundwater and inhalation of volatile organics while
showering.    By  taking  the chronic  daily   intakes   (GDI)  and
inhalation exposure concentrations  (lECs) and combining them with
the health effects criteria,  a risk level can be calculated for the
site.    The  risk  level  of IxlO'6 represents  an  upper  bound
probability of one in one  million that an  individual could contract
cancer  due to  exposure  to  the potential  carcinogen  under  the
specified exposure conditions.

In reviewing a future risk scenario,  the  following conditions were
assumed in order to determine the risk.

1.  A private well would  be installed downgradient of the Site in
the Southeast Flow path.
2.  Concentrations similar to the Vinyl  Chloride levels found in
monitoring wells where contamination was found would be  detected in
the private wells installed.
3.  1.6 liters of water  would be consumed 350  days per year for 30
years.
4.   The body weight of the  individual drinking the water  is 48
kilograms (106 pounds) and the average  lifetime would be 70 years.

Using  these  assumptions  in  combination  with  site  data,   an
individual drinking groundwater under these conditions would have
a 1 in  10,000  (10~4)  chance  of obtaining  cancer.   This estimation
is for carcinogenic compounds only.

Potential risks for noncarcinogens  are presented as the ratio of
the CDI to the reference  dose  (COI:RfD)  for each chemical,  or as
the ratio of the IEC to the reference dose concentration  (IEC:RfC)  .
The  sum of the  ratios  of all  chemicals under  consideration is
called the hazard index.   The hazard index is useful as a reference
point for gauging the potential effects of environmental exposures
to complex mixtures.   In general,  hazard indices  which are less
than one are not likely to be associated with any health risks,  and
are therefore less likely to be of regulatory concern than hazard
indices greater than one.

The summary of potential health risks associated with the site
under the  future land  use  assumptions  are provided  in Table  9
(Table 5-17 BRA of RI or Table 33 of  FS) .  This table includes both

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carcinogenic and non-carcinogenic effects.  The cumulative risk for
the Non-Contiguous  Fill Area is 6 x 10'4 or six  additional  cancer
cases  in  ten  thousand people.    The cumulative  risk  for  the
Southeast Flow Path is 1 x 1CT4 or one additional cancer case in ten
thousand people.  The cumulative risk for the Southern Flow Path is
8 x 10'6 or  eight  additional cancer cases  in one  million people.

Southeast Flow  Path
The risk associated with the  Southeast Flow Path is predominantly
due to the presence of  Vinyl  Chloride.  Vinyl Chloride  is a known
carcinogen  and  therefore  is  estimated with a higher weight-  for
causing cancer.   Vinyl  Chloride was found in one .well  above MCLs
and  ESs  during both  rounds  of the RI.   Results  from the  IGMP
indicate Vinyl Chloride was detected in two additional wells.   The
highest detection of Vinyl  Chloride  is 7ug/l in this  flowpath.
Therefore  the risk associated with the  Southeast Flow Path  is
primarily based on potential  groundwater  ingestion in this area
over a prolonged  time period.

Southern Flow Path
The upper bound lifetime excess cancer risk to a potential  future
resident through  ingestion of groundwater from the Southern Flow
Path wells is 6xlO'6.  This value is primarily due to  the presence
of   1,2-dichloroethane  and    1,2-dichloropropane  detected   in
monitoring  wells  in this  flow path.    The hazard  index for  the
southern  flow path  exceeds  one   (5)   which is  entirely  due  to
thallium.  Thallium was detected at 17ug/l.  Exposure to thallium
can be associated with  elevated enzyme levels  in blood serum  and
baldness.

Non-Contiguous Fill Area
The potential upper bound  lifetime excess cancer  risk to a  future
resident through  ingestion of  groundwater from the Non-Contiguous
Fill Area wells is 6xlO'4.  This value is predominantly  due  to  the
presence  of Arsenic  in  these wells.    However,  Benzene, 1,2-
Dichloroethane,   and  Trichloroethene  each  have  an  upper  bound
lifetime excess cancer risk greater than 1x10'6 which is  within  the
range U.S. EPA considers for taking remedial actions.    The  hazard
index for the Non-Contiguous Fill Area is ten,  which is well  in
excess of the level (one)  where health effects are expected.   The
primary chemicals accounting  for  these results  are  2-butanone,
ethylbenzene, naphthalene, arsenic, and manganese.  These results
indicate that  adverse noncarcinogenic effects could  potentially
occur if on-site groundwater from the Non-Contiguous Fill Area is
ingested on a daily basis  over many years.

The potential upper bound  lifetime excess cancer risk to a  future
resident  through  inhalation  of volatiles  while showering with
groundwater from the Non-Contiguous Fill Area is IxlO*5.  This value
is primarily due to the presence of benzene and 1,2-dichloroethane.
Benzene was detected at concentrations ranging from 1 ug/L to  21
ug/1 in seven of 12 wells.  Two detected concentrations of

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1,2-dichloroethane  (out  of 12 samples) were  4 and  9  ug/1.   The
total hazard index exceeds one  (9) .  This value is primarily due to
the  presence of xylenes,  but also  included 1,1-Dichloroethane,
Ethylbenzene  and Toluene.   Based on  the potential  exposure to
xylenes, adverse noncarcinogenic effects could potentially occur to
the  central  nervous system and respiratory  tract if groundwater
from this well  is  used for showering on  a daily basis over many
years.

E.  Ecological Risk Assessment
The ecological risk assessment evaluates the potential impacts to
nonhuman  receptors associated with  possible  exposures  to  the
chemicals  identified  in  the human health  assessment.    This
assessment  is similar to  the human risk assessment in  that it
identifies potential receptors, conducts an exposure and toxicity
assessment and  evaluates the risk characterization.   Details of
this process  are provided in section 6 of Appendix  A of the RI.
Below is a brief overview of this section.

Potential receptors evaluated for this assessment include plants,
birds, mammals,  livestock, reptiles  and amphibians.   Since it is
not  feasible nor practical  to assess  impacts to every species
potentially affected by exposure to chemicals of potential concern
it is appropriate to select "indicator" species.  These indicator
species are  representative of potential impacts in other species at
the site.

Conclusions of the ecological assessment show that it is unlikely
any adverse  affects to aquatic invertebrates,  birds  and mammalsr
livestock, and sensitive  species have occurred. The most important
potential exposure pathway for ecological receptors at this site is
associated with chemicals in sediments in  the drainage way and the
wetland  area.    There  is some potential  for adverse  impacts to
sensitive aquatic invertebrates from  exposure to 4-methylphenol in
drainage way sediments and phenol in wetland sediments.  However,
these chemicals have not been widely detected.  Overall, absolute
conclusions  regarding the potential environmental  impacts  are
difficult to make due to uncertainties surrounding the estimates of
toxicity and exposure.  Given the uncertainties and the relatively
lp_w  levels  of contaminants  of concern in  the drainage  way and
wetlands,  it  is  unlikely  any  major  adverse   affects  to  the
environment have occurred at the site.  Based on completion of the
SCQU  remedy it  is also  very  unlikely that  any  future  adverse
affects would occur.

F.  Uncertainties
The  estimates  of   risk  for  the site  have  several  associated
uncertainties.    The   primary sources  of  uncertainty  are  the
following:

*    Environmental  sampling   and  analysis,   and  selection  of
     chemicals

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 *     Exposure parameter estimation
 *     Toxicological  data


 The  risk  assessment  for  this site  should not  be construed  as
 presenting an absolute  estimate of  risk to persons  potentially
 exposed  to chemicals  from the site.   Rather,  it  is  a conservative
 analysis intended to indicate  the potential for adverse impacts  to
 occur.  Details regarding uncertainties and assumptions used in the
 risk  assessment can be obtained in Section 7.0 of the Baseline Risk
 Assessment (Appendix A  of the RI).

 VIZ.  DESCRIPTION OF ALTERNATIVES

 A.  Remedial  Action Objectives
 Upon  completion of the  source  control - operable  unit  remedial
 action,  certain objectives that were  developed during the RI  have
 been  addressed.  These  objectives include reducing  leachate  from
 entering the  groundwater  and reducing migration of  contaminants
 from  the source areas.   These  actions will contribute to attainment
 of  the  long-term  goals  of  protecting  human  health  and the
 environment  and meeting  applicable or  relevant and  appropriate
 requirements.  (ARARs).    The  main objective of  this  groundwater
 operable  unit  remedial   action  is   to  reduce   and  contain
 concentrations of contaminants in groundwater at the site thereby
 minimizing its migration.  The clean-up goals for this site will be
 to meet Federal Maximum  Contaminant Levels (MCLs), and state NR 140
 Enforcement Standards  (ESs)  and Chapter NR 140  Preventive Action
 Limits (PALs)  .  Since NR 140 PALs are the most stringent standards,
 these are  the primary goals  on which  this  action  is based.
 Consistent with Section 300.430(a)(1)(iii) (F), U.S.  EPA expects to
 return useable groundwater at  the Site to beneficial use  wherever
 practicable,  with a timeframe  that is  reasonable  given particular
 circumstances of the Site.

 Since the SCOU remedy for  this site has  already been implemented,
 the   Final  Remedy  specifically  addresses  the  reduction  of
 contaminant concentrations in groundwater at the site.  A phased
 approach has  been  taken  on  this  project  in  order  to  monitor
 progress toward clean-up objectives  and to assess the additional
 impact of the  SCOU remedy on groundwater contamination.  Monitoring
 the progress  achieved by the SCOU in effectuating clean-up goals,
 and  documenting how  such progress  is   measured,  will  also be
 objectives of this remedy.

 B.    Development of Alternatives
Alternatives  developed  in the FS  for the Final  Remedy considered
 all prior remedial actions implemented  at this site.   These actions
 include previous drum removals and work  conducted under the SCOU.
 Consideration of  these  actions  reflects a  phased  approach to
project management  that  has  been  consistently used  at this site.
This  phased  approach  allows  the  project  to  progress  while

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simultaneously monitoring the effects of previous work.  This same
approach will be used to document the progress and attainment of
groundwater clean-up  goals.

The remedial alternatives were assembled from applicable remedial
technology options.   A  wide  range of  technologies  and remedial
options were reduced  by evaluating them with respect to technical
implementability.  The alternatives surviving the initial screening
were  evaluated  and  compared  with respect  to  the nine criteria
required  by  the  NCP.     In   addition  to  the remedial  action
alternatives, the NCP requires that a no-action alternative also be
considered  for  the  site.     The no-action  alternative  serves
primarily as a point  of comparison for other alternatives.

The strategy  used to develop  alternatives  was  to first  provide
general  response  actions  typical  for  groundwater  remediation.
These actions include:

o    Institutional Controls
o    Groundwater Monitoring
o    Groundwater Controls
o    Groundwater Treatment
o    Groundwater Discharge

These general response actions  describe a variety of institutional
controls and remedial actions intended to satisfy the groundwater
objectives.  These general actions were screened to evaluate which
were implementable prior to comparison to the NCP criteria.

Institutional Controls
Institutional  controls  include  deed  restrictions and land  use
planning.  The purpose of these controls is to restrict development
and/or  installation  of  water  supply  wells in the  vicinity  of
impacted groundwater.  Deed restrictions have  been placed on the
property parcels where the fill areas are located. These parcels
are owned  by the Respondents  (WMWI  and Mr. Carl Wauer)  and the
restrictions placed  in accordance with  the SCOU remedy.   Also, .
according to State regulations, the installation of a water supply
well in a known  contaminated aquifer or within 1,200  feet of the
nearest edge  of an  abandoned  landfill  is  prohibited, unless  a
variance is granted by the WDNR.   However,  deed restrictions can
only  be implemented  by a  property owner  thereby  limiting  the
effectiveness of this requirement.   Since  deed restrictions are
already in place for  the required properties there is no need for
any additional restrictions for  this  remedy.   Enforcement of the
water supply well prohibition is dependent on the property owner or
well driller contacting the WDNR prior to well installation.  Also,
the  WDNR  can  grant variances   from the  prohibition,  so  the
prohibition  is  not   absolute,  even   if  the WDNR is  contacted.
Therefore, the effectiveness of institutional controls relating to
water supply well prohibition is  dependant upon  the site owner or


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contractor contacting the WDNR,  and is not absolute, even  if the
WDNR is contacted.

Groundwater Monitoring
Currently groundwater monitoring is ongoing from the SCOU under the
Interim Groundwater Monitoring Plan.   The goals of a groundwater
monitoring program, without additional groundwater extraction, are
to monitor changes in groundwater contaminant concentrations  within
the identified  flowpaths, and evaluate  the effectiveness of the
SCOU  activities.    In  addition  to  these  goals,  a   long-term
monitoring  program that  includes  groundwater   extraction' and
treatment would include:

o    Provide data  to assess the extraction well capture  zone,
o    Evaluate the  effects on the groundwater  from  discharge to an
     infiltration  basin,
o    Evaluate trends in groundwater contamination and the impact of
     any activities  associated with this remedy.

Groundwater Controls
Groundwater controls are active means by which contamination within
the groundwater would  be contained,   reduced and/or eliminated.
Certain   controls   were   evaluated   but   disregarded   due   to
implementability  considerations.   These  include:  1)  underground
barriers  to  reduce  groundwater  migration  from  the   site;  2)
groundwater extraction trenches;  and  3)  groundwater  control  by
injection for enhancement of  biological degradation.   Geological
features at this site prevent  underground barriers  and groundwater
extraction trenches from reducing migration away from the site. The
New Berlin and Oak Creek Formations intersect in the area of the
site thereby creating a complicated pattern of clay and sand seams.
This pattern creates an intricate  groundwater flow configuration
around the site.  Therefore a single barrier  or extraction system
such as a  wall  would not adequately  impact multiple  flow paths.
Biological  degradation  may  not   be   effective  because  in-situ
bioremediation is  not appropriate  for large  quantities of  water
containing generally low concentrations  of chlorinated aliphatic
hydrocarbons.

Groundwater controls that were retained for evaluation include: 1)
groundwater extraction wells; and 2) groundwater extraction wells
with injection  of  uncontaminated  water through  an infiltration
basin or  trench.    These controls were  retained due  to  their
potential effectiveness  at reducing contaminated groundwater and
the implementability of these specific actions.

Groundwater Treatment
Groundwater treatment  was separated  into  inorganic and organic
treatment technologies.  For the purpose of technology screening,
the discharge  limits  for  extracted  .groundwater  are  evaluated
relative to Chapter NR  140 PALs. Technologies related to treatment


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 of inorganic parameters include precipitation, reverse osmosis, ion
 exchange,  and reduction.

• Technologies  related to the treatment of organics  in  groundwater
 include biological treatment, oxidation, photolysis, air and steam
 stripping,  spray evaporation,  carbon  adsorption,  and  thermal
 destruction.   Due to  low concentrations of organic contaminants
 biological  treatment,   photolysis,  air and  steam stripping,  and
 thermal destruction would not be the most effective technologies
 comparatively and therefore were not  retained.

 Groundwater Discharge
 Discharge of  treated water to surface or groundwater, or discharge
 of untreated 'or  pretreated water to a  Publicly Owned  Treatment
 Works  (POTW)  can provide  a means of disposal  for the  extracted
 groundwater.   Surface  water discharge areas that were  considered
 included the  Fox  River, approximately 1 mile west of the site, or
 wetlands southeast  of  the site.  Groundwater reinjection was  not
 retained due to the possibility of raising the water table near the
 Stoneridge  Facility and the source  areas.   However, groundwater
 infiltration  was  retained  since the impact on elevating the  water
 table  would  be  less  than direct reinjection.   Discharge  to a
 wetland or  groundwater  infiltration must  meet Best  Available
 Technology  (BAT) requirements under ch.  NR 220,  Wis. Adm. Code, in
 the  effluent  and  NR 140 requirements  in the groundwater below  the
 discharge  area.    Discharge  to  a  wetland  is similar .to  an
 infiltration  basin  but is  more ecologically sensitive  and  would
 require more  stringent  monitoring.     Therefore,  discharge  to
 wetlands was not retained.  Discharge standards  to a surface  water
 body such  as  the  Fox River would not require similarly  stringent
 standards.  Therefore,  surface water discharge to the Fox River  and
 infiltration   basin   discharge  locations  were   retained   for
 consideration for treated  water.  POTW discharge was retained  for
 non-treated extracted  water.

 C.   Alternatives

 Alternative 1  - No Action
 Under Alternative 1 no additional  corrective  action  would be  taken
 at- the  site to address groundwater contamination.  The  removal of
 leachate from the Southeast Fill  Area,  Old Fill Area,  and Non-
 Contiguous Fill Area would continue utilizing the current method of
 pumping leachate  from  the existing collection system directly to
 the  sanitary  sewer.   The  gas collection and  flaring  would also
 continue as described in the SCOU.  The newly constructed landfill
 cap  would minimize  infiltration of rain water through waste.  In
 situ vapor extraction would  continue  in portions of  the Non-
 Contiguous  Fill Area.   Finally, deed restrictions  that  restrict
 potential well installation on-site or nearby would continue.

 Under a no-action scenario, contamination in  the groundwater  would
 not  be directly addressed.   This would result  in  continued off-site

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migration  of existing  contaminants in  the groundwater.   Also,
contaminants  would potentially  move  into  groundwater  from the
source areas.   In particular,  leachate extraction wells were not
installed  in the Non-Contiguous Fill  area  because leachate head
levels in  the area were not high enough to allow extraction to be
practicable.

A  no-action remedy would allow the site to remain  as it exists
today.   Therefore,  contamination  within the  aquifer  would  be
addressed  primarily through  attenuation and  dispersion without
active restoration. There would be no capital or operational costs
associated with this alternative, beyond  those associated with the
SCOU.

Alternative 2 - Long-Term Performance Monitoring
The   Long-Tertn   Performance   Monitoring  Alternative  involves
monitoring of  groundwater  quality over  time to  evaluate  the
effectiveness and performance of the previous activities performed
at the site.  No  groundwater  remedial  action would be taken as a
result of  this  alternative.   The  groundwater  monitoring program
would incorporate the  Interim Groundwater Monitoring Plan (IGMP)
and  is  assumed to  include  the installation of additional wells
during  the  remedial  action.    The  actual number  of  sampling
locations, the sampling frequency, and the parameter list, would be
determined during the Remedial Design.

The.  Long-term monitoring  program   would  provide   information  on
groundwater conditions  throughout the site. This alternative would
not  provide additional  protective  measures nor directly address
groundwater  standard  exceedances.   The  capital  cost  for  this
alternative would be $145,000 with Operation & Maintenance costs at
$161,000 per  annum for an estimated 30 years resulting  in a Net
Present Value of $2,620,000.

Alternative 3 - .Non-Contiguous Fill Area Groundwater Extraction and
Treatment  (The Selected Remedy)
The  purpose  of  this alternative is to directly address,  through
groundwater extraction and treatment, the groundwater contamination
identified primarily in the  vicinity of  the Non-Contiguous  Pill
Area.    By  reducing  contaminant   input  to  the  Southern  and
Southeastern Flow Paths  from the Non-Contiguous  Fill Area, which is
where the  highest concentrations  of contaminants  were found on-
site, health risks from groundwater downgradient of the Fill areas
would be reduced  and  clean-up standards  would  be  expected to be
reached  over time through  reduction of contamination  in  the
groundwater pathways and through natural  means.

Manor components of Remedial Alternative
The major features of this alternative include a  system which pumps
and  treats contaminated groundwater near  the Non-Contiguous  Fill
Area, starting at a rate of approximately 50 gallons  per minute
(gpm),  with  a  discharge  to  an  on-site  infiltration  basin.

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Treatment for VOCs and inorganics would include air stripping, an
acid  wash of  the air  stripper,  when  necessary, with possible
inclusion  of  chemical  precipitation.    If  necessary,  carbon
treatment would be installed to comply with air emission standards
(NR 445, Wis. Adm. Code).   Transportation of treatment residuals
would be to an approved facility.  The treated water may initially
be discharged,  on a  short-term basis, to the local  POTW until
treatment   systems   -are   appropriately  designed.     Long-term
groundwater monitoring would be conducted both in the vicinity of
the Non-contiguous Fill Area and  in  the South and Southeast flow
paths  to evaluate  effectiveness  and  determine   if  contingency
measures are necessary to  achieve groundwater clean-up goals (NR
140,  Wis. Adm. Code)  in all of these areas.

Alternative 3 would be implemented in a phased approach  in order to
gather the necessary data  to determine  the progress  towards,  and
achievement of, clean-up objectives.   This approach is consistent
with  the  approach to  the  overall  site  and parallels U.S.  EPA
guidance for "Evaluating the Technical Impracticability of Ground-
Water  Restoration",  September  1993.   The  implementation of  a
limited pump and treat system in the Non-Contiguous Fill Area would
occur in conjunction with  a comprehensive pilot scale  test.   The
purpose of this test would  be to determine aquifer characteristics
and evaluate discharge and treatment options.

Another goal for this alternative  will be  to continue updating the
estimate of  the  time  frame needed to reach  clean-up objectives.
Currently, it  is  difficult to assess the impact  of the  SCOU on
helping achieve groundwater clean-up.  This will be facilitated
through continued, long-term performance  monitoring  at the site.
The Performance  Evaluation Report would  include  a  section  that
evaluates remedial action  performance data from the  site  and the
progress toward achieving clean-up objectives.  This section would
be updated on  at  least  a  5 year periodic  basis and  will  include
recommendations on implementing additional remedial actions,  or
improvements  to  the  operation of   the  existing  environmental
controls.

This alternative currently contemplates the installation of four
extraction  wells downgradient  of  the North and South  Refuse
Trenches  and the  L-Shaped Fill  Area.    The  actual  number  and
location of  extraction  wells and extraction flow rates  will be
determined after  pilot-scale  testing of  the system.   The total
estimated extracted flow rate is now assumed to be 50 gallons per
minute.  This rate may be adjusted, depending on the results of the
pilot testing.  A header pipe system would connect these wells to
a treatment  system.   Parameters anticipated  to exceed discharge
standards include some VOCs, iron,  manganese,  and possibly arsenic.
Appropriate treatment of extracted groundwater is air stripping for
VOC treatment.   The air  stripper would  be  sized to  reduce  VOC
concentrations  to prescribed  effluent  limits.    If  necessary,
further treatment would be added to meet applicable air emissions

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limits.  Potential clogging of the treatment system caused by iron
and manganese precipitates would be a maintenance concern and could
be  treated  by periodic  acid  rinses  of  the  unit,  instead of
pretreating the influent using chemical precipitation.  However, if
inorganic contaminant  concentrations  continue to exceed  clean-up
standards,   then   precipitation  or  other  inorganic  treatment
technology,  such  as  ion exchange,  would be evaluated.  The  costs
for  this  alternative  assume   chemical  precipitation   will  be
included.

Off-site  discharge  to  a  POTW, such  as  Milwaukee  Metropolitan
Sewerage  District  (MMSD),  may be  appropriate  until extracted
groundwater  is characterized  and confirmation is  obtained that it
can  be treated  to  levels adequate  to  permit  discharge  to an
infiltration  basin.    The  cost  for  this alternative   assumes
discharge during the first year of  groundwater extraction  would be
directly  to  MMSD.   On-site  treatment using air stripping  would
begin the second year of groundwater extraction.

Discharge to an infiltration basin would meet ch. 'NR 220, Wis. Adm.
Code, WPDES  Best  Available Technology (BAT) requirements, at the
point of  discharge and ch. NR  140, Wis.  Adm.  Code, PALs  for all
contaminants  in  the groundwater at  a  point directly below the
discharge zone.  To the extent  it is subsequently determined that
it is not technically or economically  feasible to  achieve  PALs, NR
140.28 provides substantive standards  for granting exemptions from
the requirement to achieve PALs. Such exemption levels may not be
higher than the ESs.

Alternative   3   is  planned  to  capture  existing  groundwater
contaminants and prevent additional migration of contaminants from
this  source  through  contaminant removal  and  containment.   The
Southern and  Southeast  Flow Paths  would both be affected by this
action.   The impact  of this  action in  combination  with the SCOU
cannot be precisely determined  at this time.  One of  the  goals of
this action  will  be  to measure  the effectiveness of this action
coupled  with  the  SCOU  remedy to  determine  progress   towards
achieving clean-up goals.

The  capital  cost  for  this alternative  is  estimated  to  be $1.2
million.  The operation and maintenance  costs have a total present
value of  approximately $6.2  million  over a thirty year  period.
Therefore the total Present Value Cost for this alternative is $7.4
million.

Alternative 4: Non-Contiguous Fill Area and Perimeter Groundwater
Extraction and Treatment
Alternative 4 contains 3 options. The options are based on the two
groundwater  flow  paths  known as the  Southern  and Southeast Flow
Paths.  Alternative  4A addresses contamination  in  the Southeast
Flow   Path   through  groundwater   extraction   and   treatment.
Alternative 46 addresses  contamination  in the  Southern Flow Path

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through  the same  means.    Alternative  4 combines  4A  and  4B to
address all downgradient groundwater flow.  All of the options  also
include pumping and treating contaminated groundwater from the  Non-
Contiguous Fill Area as provided in Alternative 3.  The purposes of
this   alternative   are:  1)   to  directly   address  groundwater
contamination within the Southern and Southeast  Flow Paths through
hydraulic  containment and  groundwater  extraction;  2)  to reduce
related risk in  this  groundwater  to acceptable levels and;  3) to
reduce  groundwater contamination in the  vicinity of  the   Non-
Contiguous Fill Area.

Manor Elements of Alternative
The  major elements  of these  alternatives  include:  groundwater
monitoring, extraction of contaminated groundwater, treatment and
discharge.  This alternative has been divided  into options  that
address  the  Southern  and  Southeast   groundwater  flows   both
separately and combined.  The extracted groundwater generated under
Alternative 4, would exceed  the capacity of the infiltration basin,
which is limited to an estimated 100-200 gpm.   The same is  true for
Alternatives 4A and 4B.

Similar to Alternative 3, this alternative would have the goal of
meeting U.S. EPA's.Groundwater Protection Strategy.  In addition,
the groundwater monitoring data may  be used to suggest adjustments
to the system to achieve clean-up standards.

Alternative 4A (Southeast Plow Path)
Alternative 4A assumes that 6 extraction wells averaging 100  feet
deep (3 wells at 70 feet deep, 3 wells at 130 feet deep) would be
installed.   The total  extracted  flow  rate  for  the  southeast
perimeter extraction system is  assumed to be 60 gpm.  The actual
number of extraction wells and flow rate needed to accomplish the
purposes  of this  alternative  would be determined during  the
Remedial Design.   Similar to Alternative 3, treatment for VOCs and
inorganics would include  air stripping,  acid washing of  the  air
stripper,  when   necessary,  and  possible inclusion of  chemical
precipitation or ion exchange.  Potential clogging of the treatment
system  (air stripping tower)  caused  by  iron and manganese is  a
maintenance concern and  would be  treated  periodically  by  acid
rinsing  the unit.    If  necessary,  carbon   treatment  would be
installed to comply with air emission standards  (NR  445, Wis. Adm.
Code) and transportation of  residuals to an approved facility.  The
discharge of  treated water would be to an  on-site infiltration
basin and/or to the Fox River.  This  decision  would be dependent on
information obtained during the Remedial Design regarding capacity
constraints  of  the   infiltration   basin  and  impacts  on  the
groundwater table.  Any discharge to the Fox River would likely
require a ROD Amendment and public comment.

The .capital cost for  this alternative is estimated to  be $3.026
million.  The  operation and maintenance costs have a total present
value  of  approximately  $842,000  over  a   thirty  year  period.

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Therefore  the total Present  Value Cost  for  this alternative is
$14.9 million.

Alternative 4B:  (Southern  Flow  Path)
Alternative 4B specifically addresses contamination in the Southern
Flow  Path  through groundwater  extraction and treatment.   The
extraction  system  is  assumed  to  include  5  extraction  wells
averaging  160 ft.  deep.   The total  extracted flow for the  south
perimeter  extraction  system  is  assumed  to  be  125  gpm.   This
combined with the flow  rate from the Non-Contiguous Pill Area  would
total  175  gpm.    The  FS  (Appendix  G)   provides   calculations
indicating that the proposed basin size is large enough to handle
the combined  flow volume of 235 gpm.  However,  these  calculations
do  not  take  into  account  the  reduction  in  permeability due to
sediment build-up and potential  icing during the winter,  affects on
raising the groundwater table,  and current capacity of the  basin
for stormwater and run-off  from other local features.   Therefore an
appropriate  range  for discharge  is between  100  and  200  gpm.
Discharge to a second point may be necessary.  Any discharge to the
Fox River would likely require a ROD Amendment and public  comment.

The capital cost for this  alternative is estimated to.be  $3.207
million.  The operation and maintenance  costs  have a total present
value  of  approximately  $896,000 over  a thirty  year   period.
Therefore  the total Present Value Cost for  this  alternative is
$15.8 million.

Alternative 4:  (Southeast  and Southern  Flow Paths)
Alternative 4 is a combination  of Alternatives 4A and 4B.   The
total  extracted flow  for  this perimeter extraction  system  in
combination with the Non-Contiguous Fill Area  is assumed to be 245
gpm.  This extraction system would most likely  require  discharge to
the  Fox River  due  to  capacity constraints  associated with the
infiltration  basin.   Discharges of extracted groundwater to the
river are subject to the Wisconsin Pollutant Discharge Elimination
System  (WPDES)  program.   Any discharge  to the Fox  River would
likely require a ROD Amendment and public  comment.

Potential discharge to  the  MMSD may be feasible for the low volume,
more highly contaminated water collected at the start of  extraction
from the  Non-Contiguous Fill  Area.  Any discharge  to MMSD would
have to meet MMSD pretreatment and volume requirements.  The actual
number of wells, flow rate, treatment  system,  and discharge system
would be determined during  the Remedial Design phase.

Discharge to an infiltration basin would meet  WPDES Best Available
Technology  (BAT) requirements (214.12). at the point of discharge
and ch. NR  140, Wis. Adm.  Code,  PALs for all  contaminants in the
groundwater at a point directly below the  discharge zone.  To the
extent it is subsequently determined  that it is not technically or
economically  feasible   to achieve   PALs, NR  140.28   provides
substantive standards for granting exemptions  from the requirement

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to achieve PALs.  Such exemption levels may not be higher than the
ESs.

The capital  cost  for  this  alternative  is estimated to be  $3.464
million.  The operation and maintenance costs have a  total present
value  of  approximately  $950,000  over a  thirty  year period.
Therefore  the total  Present  Value Cost for  this alternative is
$16.7 million.

VIZI.     SUMMARY OF  COMPARATIVE ANALYSIS OP ALTERNATIVES

A.   Introduction
U.S.  EPA  has  established nine  criteria  that  balance health,
technical,   and  cost  considerations  to   determine   the  most
appropriate  alternative.  The criteria analyze the selected remedy
so  that  the  remedy  is  protective  of   human  health   and   the
environment,  attains  ARARs,   is  cost effective,   and   utilizes
permanent  solutions  and  treatment  technologies  to the maximum
extent practicable.  The remedial alternatives developed  in the FS
have been evaluated and compared using these nine criteria which
are set forth in the NCP at 40 CFR Part 300.430 (e) (9) (iii) .  These
nine criteria are summarized as follows:

OVERALL PROTECTION  OF PUBLIC HEALTH AND THE ENVIRONMENT addresses
whether a remedy provides adequate protection of human health  and
the environment and describes how risks posed through  each  exposure
pathway are  eliminated, reduced, or controlled through treatment,
engineering  controls,  or institutional controls.

COMPLIANCE WITH APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS
(ARARs) addresses whether a remedy will meet all other Federal  and
State  environmental  statutes  and  regulations   and/or   provides
grounds for  invoking a waiver.

LONG-TERM EFFECTIVENESS AND PERMANENCE refers to the ability of a
remedy to  maintain reliable  protection of human  health and  the
environment  over time, once clean-up standards have been  met.

REDUCTION OF CONTAMINANT TOXICITY,  MOBILITY, OR  VOLUME through
treatment addresses the anticipated  performance of the treatment
technologies a remedy may employ.

SHORT-TERM EFFECTIVENESS addresses the period of  time  needed to
achieve protection,  and any adverse impacts on human health and  the
environment  that   may  be  posed  during  the  construction   and
implementation period, until clean-up standards are achieved.

IMPLEMENTABILITY  addresses   the   technical   and  administrative
feasibility  of  a  remedy, including the availability of materials
and services needed to implement a particular option.
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COST includes estimated initial capital,  operation and maintenance
(O&M) costs, and net present worth costs.


STATE ACCEPTANCE  indicates whether,  based on  its  review of the
RI/FS and Proposed Plan,  the State concurs with, opposes,  or has no
comment on the preferred alternative  at  the present time.

COMMUNITY ACCEPTANCE is based on comments received from the public
during the public comment period.  These comments are assessed in
the responsiveness summary  attached to this ROD.


B.     Remedial Alternatives  for Groundwater Remediation
The following briefly  describes how the selected alternative for
groundwater remediation  compares to other alternatives using the
nine criteria.

 1. Threshold Criteria

The two most  important criteria  are  statutory requirements that
must be satisfied by any alternative in order for it to be eligible
for selection.  These two criteria are discussed below.

 a. OVERALL PROTECTION OF HUMAN HEALTH AND THE  ENVIRONMENT
This final remedy addresses groundwater, therefore the discussion
of  protection  of  human  health and the  environment  pertains
specifically to the groundwater media.  The SCOU has addressed risk
from  direct  contact and air media scenarios.   According to the
Baseline Risk  Assessment within the RI,  the  cancer  risk under
current land use conditions is  within acceptable U.S. EPA ranges.
However,  the  future  risk  scenario  indicates  risk  to  potential
future  groundwater  drinking  wells  both  on   the   site   and
downgradient.   Therefore  protection of  human  health  and  the
environment is addressed  from  a potential future use scenario as
opposed to a current use scenario.

Alternatives 1 and  2 are not protective of human health and the
environment  due   to  the  continued  movement  of  groundwater
contamination  and potential  human  exposure  via  future  private
wells.

Alternative  3  would  provide   appropriate  protection  since  it
addresses contamination in  the  groundwater in the vicinity of the
Non-Contiguous Fill Area.  The  extraction system is anticipated to
capture existing groundwater and prevent additional migration of
contaminants.   The  Southern  and Southeast  Flow Paths  would be
affected by  remedial activities proposed  for the Non-Contiguous
Fill Area,  because  the Non-Contiguous Fill  Area is upgradient of
both Flow Paths.   Alternative 3 does not  directly address, through
groundwater extraction and  treatment, contamination in exceedance
of  groundwater standards  beyond the Non-Contiguous Fill  Area.

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However,  contamination  and potential  risk  in groundwater  use
scenarios are greater in the Non-Contiguous Fill Area.  Therefore
reduction of contamination in groundwater in this area  coupled with
the SCOU activities are expected to lower groundwater contaminant
levels and therefore reduce associated potential risk levels.  If
subsequent monitoring  shows that the contaminant  levels  are not
being reduced adequately,  this  alternative allows  for additional
remedial actions, including actions that may  be similar to those
described in Alternative 4, to be implemented in a phased manner.
The way in which additional extraction and  treatment may be phased
in is discussed in detail in the description of the selected remedy
and the compliance with ARARs criteria,  below.

Alternative  4  would  also  provide  protection  by  controlling
groundwater flow  to a  greater extent than  any other alternative.
This  Alternative  includes  groundwater  extraction  to  capture
existing  contaminants   and  prevent  additional   migration  of
contaminants  associated   with   the  Non-Contiguous  Fill  Area,
Southeast  Flow  Path   (Alternative  4A)  and  Southern Flow  Path
(Alternative 4B) .   At this time  it  is  difficult  to  measure the
difference  in  the  effect  on  groundwater  contamination  that
Alternative 4 would provide over Alternative 3.   Since  the Non-
Contiguous Fill Area has higher contaminant  concentrations than the
Southern  and Southeast  Flow  Paths the  additional reduction  of
contamination produced by extraction in these  areas  is  unknown.
However,  Alternative  4  provides  the only method  for  immediate
direct extraction of contamination from all sources.

Protectiveness  of  human  health and  the environment  for  all
alternatives are based on the Baseline Risk Assessment (BRA) .  The
BRA evaluates risk under two scenarios; current land use conditions
and potential  future  land  use.   Currently there  are no  private
residences using the  groundwater aquifer  since a public  water
supply has been constructed.  Therefore the current risk scenario
is negligible.  For all alternatives,  the contaminated  areas of the
aquifer would  remain  unusable  during the  period of restoration.
The alternatives are enhanced in their effectiveness in protecting
public health by the implementation of the Source-Control Operable
Unit remedial components.

b.      COMPLIANCE WITH  APPLICABLE  OR  RELEVANT AND  APPROPRIATE
        REQUIREMENTS  (ARARs)
Alternatives  1 & 2  do  not include  groundwater  extraction  and
treatment to directly address  the  identified  State  and  Federal
groundwater  exceedances.   These alternatives rely upon  the SCOU
remedial components to reduce contaminant  (leachate) loading into
the groundwater, and periodic monitoring to provide information on
changing conditions at the  site.   While the SCOU activities will
enhance groundwater clean-up through reducing  contaminant loading,
it will not address any current contamination within the aquifer.
Alternatives 1 & 2 would rely on attenuation and dispersion as the
means to achieve groundwater standards.  U.S.  EPA does not believe

                                32

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that  these  methods  would  be  sufficient  to  meet  the stated
groundwater clean-up  standards.      Sections NR 140.24(2) and NR
140.26(2), Wis.  Adm.  Code, outline  the  response objectives that
apply  to  this site.   These  sections require  that contaminated
groundwater  be  restored   where  technically  and  economically
feasible,  to achieve PALs.   U.S.  EPA does not believe Alternatives
1 & 2 would effectively restore groundwater  within an  appropriate
timeframe.  Active remediation of the groundwater is necessary at
this site  to achieve groundwater  clean-up standards.  Alternatives
1 & 2, if they could achieve standards over  time  (it is not known
at this time if they would) , would take many  more years to achieve
the standards  than  Alternatives  3 or 4.   Therefore it is likely
that Alternatives 1 & 2 would not comply with ARARs.

Alternative 3 directly addresses  groundwater  contamination through
extraction and treatment of the  main area" of contamination •» the
Non-Contiguous Fill  Area.  The groundwater extraction and treatment
in Alternative 3 addresses the most highly contaminated  groundwater
on site,  which is  upgradient of the  Southeast  and  Southern Flow
Paths  containing  lower levels of  contamination.   Alternative 3
relies upon  natural attenuation to reduce  existing  groundwater
contamination  in those portions  of the  aquifer not addressed by
groundwater extraction wells.  Based on data  from the RI,  U.S. EPA
believes that Alternative 3 would be more effective  in addressing
contamination  in the  Southeast  Flow Path  as  compared to  the
Southern Flow Path.   It is expected that the concentration of the
main contaminant in the Southeast Flow Path,  Vinyl Chloride, would
be  reduced to  comply with groundwater  standards  through  this
action.  Moreover,  a phased approach to  Alternative 3 allows for
the implementation  of  additional remedial  actions,   including the
expansion of the scope and zone of  influence  of the  groundwater
pump  and   treat  component  if  it  is shown,   through long-term
groundwater monitoring, that  groundwater ARARs are  not  being or
will not be achieved.  For example,  if monitoring wells  show, after
a sufficient number of monitoring events,  that state and federal
groundwater standards  are  consistently met,  the  system  could be
turned off, in whole  or  part.   If  groundwater  standards are not
obtained,  but a decreasing  trend is shown, then the system would
continue to be operated with continued monitoring.  If  contaminant
concentrations stay at the same level  or  are  increasing,  then
additional actions -may be  taken.  These  additional  actions could
include, but are not limited to:  adjustments  to  the source control
measures such as leachate  extraction, alternate pumping or pulse
pumping at current groundwater extraction wells,  or installation of
additional groundwater extraction wells in the areas addressed by
Alternative 4.   This  final option may require  an Explanation of
Significant Difference or  ROD Amendment  if modifications  have
significant technical  or  cost  implications.   Determination  of
adequate  progress  towards  clean-up goals  will  be  measured
periodically after  system  start  up.^  The  first evaluation would
occur within 5 years after  the implementation of the  SCOU  actions.


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Alternative 4 would also directly address groundwater contamination
through extraction and treatment in the Non-Contiguous Fill Area,
the Southeast Flow Path (4A),  and the  Southern Flow Path(4B) .   The
groundwater extraction and treatment in Alternative 4 addresses  the
most  highly  contaminated groundwater  on  site  as  well  as   the
groundwater at the perimeter of the waste boundaries, which is  the
point of compliance for the groundwater standards.  Alternative 4.
would provide additional effectiveness over Alternative 3  and would
satisfy the  compliance with ARAR  criteria.   However,  given  the
relatively  low concentrations  beyond the  waste limits  and   the
limited number of sampling  rounds from  the  RI,  the  additional
effectiveness  in  reaching clean-up objectives with Alternative 4
over  Alternative  3   cannot  be  predicted  at  this time.     The
performance of a  pump and treat system in Alternative 4 would be
reviewed  regularly  to  assess  its  effectiveness  in  achieving
remediation goals.

 2.   Primary Balancing Criteria

Five primary balancing criteria are used to identify major trade-
offs  between  the remedial alternatives which  satisfy  the   two
threshold criteria.   These trade-offs  are ultimately balanced to
identify the preferred alternative and to  select  the final remedy.
Because Alternatives  1 and 2 do not satisfy the threshold criteria,
they will not be  evaluated by the primary balancing criteria.

a.  LONG-TERM EFFECTIVENESS AMD PERMANENCE
Alternative 3 would include extraction of contaminated groundwater
in the Non-Contiguous Fill Area that will also reduce the loading
of contamination  into both the Southern and Southeast Flow Paths.
This reduction in loading,  in combination  with  the reduction  in
loadings achieved by the SCOD remedial components,  is expected to
lower contaminant concentrations  in  these  flow  paths.   Although
this alternative does not directly remove contaminants downgradient
of the Old Fill area and Southeast Fill area, U.S. EPA believes the
present concentrations which  are already close  to  MCLs  would  be
attenuated  through   natural   processes  such  as  degradation,
adsorption,   and  dilution.     The  contaminants  found  in  these
downgradient flow paths represent a potential  future use risk of l
x 10** and a hazard index greater than one.  Additional information
obtained from monitoring after the remedy has been installed will
be used to confirm the clean-up time  frame  and the capability of
the remedy to keep concentrations at or below clean-up objectives
at all monitoring points.  Alternative 3 would be supplemented,  if
necessary, through additional remedial actions, including expansion
of the groundwater pump and treat action, to assure achievement of
the clean-up standards. This Alternative, in  combination with the
previous actions,  would  provide long term  effectiveness through
minimizing the additional contaminants reaching the  aquifer  and
continuous reduction of existing contaminants  in the groundwater.
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Alternative  4  would provide  long term  effectiveness similar to
Alternative 3 with the addition of immediate groundwater extraction
along  the perimeter  of  the  fill  areas.   The  installation of
extraction wells  along the southern  and/or southeast flow paths
would  further  contain the movement  of groundwater contamination
currently  in   these   areas   and  therefore  potentially  reduce
concentrations  in a  shorter time  period.   However,  long term
effectiveness would not be substantially affected by Alternative 4
since  the  additional  actions do  not address the  main source of
contamination.   The primary  difference between Alternative 4 and
Alternative  3  is  that additional  containment  through extraction
will occur in Alternative 4.  Both alternatives would reduce the
level of residual  health risk  associated with existing groundwater
contamination  in  proportion to  the  reduction  of  groundwater
contaminants removed  from  the  aquifer.    However,  many  of  the
organic  and  inorganic  contaminants  present are  expected  to  be
reduced  to  levels  near  the  analytical  detection limit  in  the
extracted  groundwater,   causing   difficulty  in  verifying  the
treatment's effectiveness in reaching clean-up standards.

b.   REDUCTION IN TOXICITY, MOBILITY, OR VOLUME THROUGH
     TREATMENT
Alternatives 3  and 4 provide groundwater extraction and treatment
that   is   intended  to   remove  and   treat   those  contaminant
concentrations  from  the  aquifer  and limit potential migration.
Treatment would occur on all extracted  groundwater  through  air
stripping for VOCs and precipitation for inorganics. Air stripping
is a proven technology in effectively removing VOCs from water as
well as precipitation is a proven method for removing inorganics.
There  would  be no difference in treatment technologies between
Alternatives 3  and 4 as  currently proposed. However, under both
alternatives,  if   results from  the  remedial  design pilot  test
indicate that additional treatment is necessary to reach discharge
standards then  treatment technologies may be modified.  Alternative
4, and to a  lesser extent Alternatives 4A and  4B, would restrict
mobility of groundwater contamination through hydraulic control of
the aquifer  to  a  greater  extent than Alternative -3.  Because  the
additional volume of groundwater addressed in Alternative 4 is not
nearly as  highly  contaminated  as  the groundwater  that  would  be
addressed under Alternative  3,  the  additional  contamination  and
risk reduction provided  by  Alternatives  4,  4A,  and 4B  is  not
proportional to the additional volumes extracted and cost expended.

c.  SHORT-TERM EFFECTIVENESS
None of  the  alternatives would pose  a substantial  risk  to  the
community, workers, or the environment  during  remedial  actions.
Precautionary  actions,  through the   remedial  action  health  and
safety plan,  would address risks to on-site workers and potential
off-site risks posed by cleanup-related activities.

Installation of groundwater extraction wells, treatment facilities,
and a  discharge system  can be accomplished in one construction

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season, with minimal disturbance of contaminated soils.  This time
frame may be extended, if necessary, to gather  information during
the remedial  design pilot test  and if supplemental  activity is
required  in  response  to monitoring   results.   The  risks  of
construction activities  for  Alternatives  3 and 4 are adequately
managed  through the  use  of personal  protective equipment  for
construction workers.

d.  XMPLEMENTABILXTY
Implementability  refers  to  the  technical  and  administrative
feasibility of constructing and operating the remedy described in
the alternative.   Alternatives 3  & 4  would both be  technically
feasible  alternatives.    Groundwater extraction wells with  air
stripping for organics and precipitation for inorganics are common
technologies  that  have  been proven feasible  and effective  on
numerous occasions.  All materials and services required for either
alternative would  be readily  available and therefore  technical
feasibility is not a concern for either alternative.

Alternative 3 would require  discharge  on-site  to an infiltration
basin.   There  would not  be the  institutional  requirements  of
obtaining permission from local authorities or private citizens for
this work.   Assuming that discharge ARARs  (specifically,  BAT &
PALs)  were met for the State of Wisconsin, Alternative 3 would be
administratively  feasible.   Under  Alternatives  4,  4A  or  4B,
discharge of treated groundwater would likely take place at the Fox
River.  The reasoning for this discharge location is the effluent
volume would likely be  greater than the capacity of  the  on-site
infiltration basin.   Discharging treated groundwater to  the  Fox
River could be  difficult to execute for  administrative reasons.
The Cities  of Muskego  and Big  Bend would need to approve  the
project as well as Waukesha County.  In addition, easements would
need  to be  obtained  from several  private property owners  to
construct the pipeline and lift/pump stations and a WPDES permit
would be required.  The pipeline would need .to cross at -least eight
roads, including one county highway.  Based  on  these  factors  the
administrative feasibility of Alternatives 4, 4A and  4B would be
questionable.

e*.  COSTS
The estimated  costs for  all  of the FS alternatives are  listed
below.  The  first column list the capital or construction costs for
the project.   The  second column  are  the costs to operate  the
remedial system once it  is constructed.   The final column is  the
Present Net Worth.

                          Annual
        Capital  Cost      O&M  Costs               Total Cost
1.0                0                      0
2.       $145,000         $161,000              $ 2,620,000
3.    $1,218,000        $417,000              $ 7,410,000
4.    $3,464,000        $950,000             $  16,700,000

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4a.   $3,026,000         $842,000              $  14,900,000
4b.   $3,207,000         $869,000              $  15,800,000
The estimated time frame for Operation and Maintenance costs is 30
years with a 5% discount factor.  As with all costs estimated in a
Feasibility Study, a range of  -30%  to  +50%  is applicable  to cover
variations in actual cost.

3.  Modifying Criteria

a.  STATE ACCEPTANCE
The WDNR has been the support agency for the RI/FS and has  reviewed
this ROD.  The WDNR concurs with the selected remedial action.  In
addition,  the  WDNR does  not  feel  that  Alternatives  1 or 2 are
protective or would attain ARARs.  Therefore, Alternatives 1 and 2
are not  acceptable to the  State.   Sections  NR 140.24(2) and NR
140.26(2), Wis.  Adm.  Code, outline the  response objectives that
apply  to this  site.   These  sections specify  that  contaminated
groundwater be restored in a reasonable period  of  time, and,where
technically and economically feasible,  be restored to achieve PALs.
Alternative 3 is  acceptable to the WDNR given that there will be
continuous  monitoring and the  requirement  to  take additional
remedial  actions  to ensure  progress  towards  achieving  clean-up
goals  in a reasonable period of  time.   Specifically,  a phased
approach that allows adjustments  to  the SCOU and groundwater remedy
is imperative for the State under Alternative 3. Alternative 4 is
supported by the State as well.

b.  COMMUNITY ACCEPTANCE
Comments  have been submitted by the  community, local government
officials, and  potentially responsible  parties  (PRPs).    Issues
presented  in the  comments were  directed  toward the inclusion of
groundwater monitoring at private residences surrounding the  site.
Comments and responses to those  comments are described in greater
detail in the Responsiveness Summary attached to this  ROD.

Alternative 4 would  require  additional  public comment from the
community, especially residents  of  Big Bend.  Given the number of
easements that would be required for installation of the discharge
line it  is expected- that  additional information would have  to be
provided  to  the  community  prior to  the  selection   of  this
alternative,  because that  requirement was not sufficiently clear in
the Proposed Plan.

C.  Summary
Based on a comparison of the nine criteria, Alternatives I  and 2 do
not provide protection from all of the potential risks at  the site
and do  not comply with  ARARs.   They therefore do  not  meet the
threshold test for selection of a remedial alternative at the site.
Alternative 3 would  be .protective  of  human health by addressing

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groundwater   contamination  in  the  Non-Contiguous  Fill   Area.
'Concentrations  of  contaminants  were greatest  in  this  area,  so
addressing that area would provide the most efficient reduction of
groundwater  contamination through extraction and treatment.   In
addition,  groundwater  from this area  is connected to the Southern
and Southeast flow paths.   Addressing that area would contribute to
the reduction of  contaminants downgradient of the fill areas  and
help   achieve  clean-up  goals  at   the   point  of  compliance.
Alternative  4,  similar to  Alternative  3,  would   fulfill both
threshold  criteria.    Protectiveness to  human  health and  the
environment  and compliance with ARARs would be provided through
either of  these groundwater  extraction  and containment remedies.
As noted in  the Proposed  Plan, an important element  of compliance
with  these criteria for  Alternative  3  is  the  implementation  of
additional measures  if  monitoring  data  demonstrates that  the
Alternative,  in combination with the SCOU, is not contributing to
achievement  of  groundwater  clean-up  standards  in  the  South  and
Southeast  flow paths.

Alternatives 3 and 4 would both satisfy the long  term effectiveness
and permanence criteria.  Both alternatives would  provide adequacy
and reliability of controls  and  the magnitude of  residual risk
associated with these Alternatives is minimal.   Treatment would be
identical  for Alternatives 3  and  4  in all  respects except that
Alternative 4 would treat a greater volume of water.

Construction  of either Alternative 3 or 4 would  not present  any
significant risk to the community.  By following  proper site safety
procedures any  risk   commonly  associated  with  this  type   of
construction work would be alleviated. Environmental impacts  would
be  minimal  or  non-existent  assuming that  proper  handling  and
disposal procedures are followed.  All of these  factors contribute
to  both Alternatives  satisfying the  short-term   effectiveness
criteria.

Since  Alternative  3 would require construction of  a groundwater
pump and treat system primarily within the property boundary  there
are no anticipated technical or administrative difficulties at this
time.      Extraction   well  installation,   air  stripping,    and
precipitation are  standard technologies that would be technically
feasible and practicable  to construct.    Therefore  Alternative 3
would  be impleraentable  and satisfy this criteria.  Alternative 4,
however, would likely require agreements with two municipalities,
Waukesha  County,   the  WDNR  and  several  private  residences   to
construct  a discharge pipeline from the site to the  Fox River  and
obtain a WPDES  discharge  permit.   While  U.S. EPA has coordinated
projects similar  in nature,  there  are  no assurances that  these
administrative requirements can be completed.

The Present  Net Value  costs for Alternative  3  total $7,410,000.
Capital costs are estimated at $1,218,000 and operational costs at
$417,000 per year for  30  years.   Alternative  4  has Present  Net

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Value  costs  as  follows;  $14,900,000  (4a,  Southeast Flow  Path),
$15,800,000  (4b, Southern Flow Path),  and $16,700,000  (4a & 4b) .
Costs for Alternative 4 are  substantially greater than Alternative
3 due primarily to the .greater costs for Operation and Maintenance
over the 30 year period.  The actual capital costs are similar for
both alternatives.  However the volume of extracted groundwater  in
Alternative 4 would be double the amount in Alternative  3.   To the
extent  additional  phases   are  required  upon  implementation   of
Alternative 3, the present value costs of Alternative 3 would still
be significantly lower than  Alternative 4 because: (1) expansion  of
the  system would  be deferred for several  years,  substantially
reducing  the  present value  of those costs;  and  (2) contaminant
reductions achieved by the SCOU and operation of the system  in the
NCF area may permit any later phases to be more  limited than what
is anticipated in Alternative 4.

The WDNR concurs with Alternatives  3 and 4 but does not concur with
either Alternative 1 or 2.  WDNR does not believe alternatives 1  or
2 are protective of  human health or comply with ARARs.   However,
Alternative  3 is  acceptable to  WDNR given  tha't  the  remedy   be
implemented in a phased approach  and that the  effectiveness  of the
remedy is measured periodically, and would be expanded if necessary
to  achieve  clean-up  standards.    The  WDNR  also  concurs with
Alternative 4 and believes this extraction and containment  option
provides  the greatest  chance of  complying  with  ARARs in  the
shortest .period of time.  It is expected,  however,  that Alternative
3 would achieve compliance with groundwater ARARs in an acceptable
time period at substantially lower cost.

IX.     THE SELECTED REMEDY

Based on  the evaluations of  the alternatives, U.S. EPA  and the
State of Wisconsin believe that the selected remedy (Alternative 3)
will be protective of human health and the environment, comply with
ARARs, be cost effective, and will utilize permanent solutions to
the maximum extent practicable.

The selected remedy includes:

•       Groundwater monitoring,
•       Groundwater pumping  test(s),
•       Groundwater"  extraction  in  the  vicinity  of  the  Non-
        Contiguous  Fill  Area,
•       On-site  treatment of extracted water  for contaminants  as
        deemed necessary from tests during remedial design,
•       Discharge of  treated  water to  an infiltration basin  or
        MMSD,  as  deemed necessary  during remedial  design  pilot
        tests,
•       Disposal  of treatment  residuals,  if necessary,
•       Monitoring  and  evaluation  of  the  effectiveness  of  the
        groundwater extraction system in achieving progress toward
        clean-up  standards,  and

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        Expansion of the system if data on the performance of the
        system  indicates  that  expansion  is  necessary  to  make
        progress toward clean-up standards.


Alternative 3 will be implemented in a  phased approach in  order to
gather  data  to determine  the progress achieved  in effectuating
clean-up objectives.  Therefore implementation  of  limited  pump and
treat in the  Non-Contiguous  Fill Area  would occur in conjunction
with pilot  scale phase testing to determine aquifer characteristics
and  evaluate  discharge  .and  treatment  options.    Groundwater
monitoring will  be conducted to correspond  with  the pilot scale
testing and continue after the remedy is constructed.  Monitoring
results  will  be   used  to   periodically   evaluate  effects  of
groundwater extraction  on the contaminant plume.   The monitoring
results will  also  be used to better define  the plume  within the
Non-Contiguous Fill Area and downgradient of this area.  Additional
measures to  effectively evaluate  groundwater  plume and  aquifer
characteristics may be implemented as deemed necessary by U.S. EPA,
in consultation with WDNR, during the pilot scale test.

Pre and post-test groundwater quality testing will  be performed for
treatment system design and evaluation purposes.   A Pilot-Scale
Evaluation Report (PER)  will be submitted for approval by U.S. EPA,
in consultation with WDNR.  This report would outline the results
of the pilot scale test and provide recommendations for treatment
system design, discharge location and rates, monitoring locations
and recommendations  for additional  action  if sufficient progress
toward  achieving  clean-up  goals  has  not  been  attained.    In
addition, the PER would include a plan for measuring the progress
towards clean-up goals.  Attachment B. "Performance Evaluations for
Pump and Treat Remediations" provides information  on mathematical,
statistical,  or graphical methods  to evaluate  the performance of
pump and treat remediations.   This reference  is  consistent with
U.S.  EPA  guidance  "Methods  for  Monitoring Pump  and  Treat
Performance"   June  1994.  The decision on  which  method  is  more
suitable for  the Muskego site will be based on the  pilot scale test
and will be made by U.S. EPA, in consultation with WDNR.

Any  additional   action  beyond  adjustments  to  the  original
groundwater extraction  system and source control measures would
require review by U.S. EPA in consultation with  WDNR.  Actions that
would require an off-site surface water discharge  of  extracted
water would likely require  a ROD Amendment  and therefore public
comment would be solicited.

As previously  mentioned,  this alternative  allows  for contingency
actions as determined necessary by U.S. EPA, in consultation with
WDNR.  The objective of the groundwater monitoring program will be
to provide information in order to measure  progress achieved in
effectuating  the clean-up  objectives.   Unless  progress toward
clean-up objectives  has been demonstrated by  the first periodic

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review,  contingency actions  will have  to be  implemented.    For
example,  if  monitoring wells show,  after a sufficient number of
monitoring events, that state  and federal groundwater standards are
consistently met, the  system  could be turned off.   If  groundwater
standards are not obtained, but a decreasing trend  is  shown,  then
the system would continue to be operated with continued monitoring.
If  contaminant  concentrations  stay at  the  same  level  or  are
increasing, then contingency  actions may be taken.  These  actions
could  include,  but  are not limited to:  additional  source  control
measures  such  as  leachate extraction,  alternate 'pumping or pulse
pumping at current groundwater extraction wells,  or installation of
additional groundwater extraction wells.   This final option may
require an Explanation of Significant Difference or ROD Amendment
if modifications have significant technical or  cost implications.
Determination of adequate progress towards clean-up goals  will be
measured periodically after system start up.  The first evaluation
would  occur  within  5 years after the implementation of the  SCOU
actions.  The clean-up goals for the  site are the NR  140 Preventive
Action Limits  (PALs),  which must be met  at and beyond the waste
boundaries   (edge   of   waste).      Consistent    with    Section
300.430(a) (1) (iii)(F),   U.S.   EPA   expects  to  return   useable
groundwater  at  the  Site to beneficial  use wherever practicable,
within  a  timeframe  that  is reasonable  given  the  particular
circumstances of the Site.                          -

A periodic review, as described in Alternative 3, will  be prepared
that evaluates all remedial actions  performed at the site  against
clean-up objectives. These reviews will  provide  recommendations on
implementing  additional  remedial  actions,  such   as  installing
additional  groundwater  or   leachate  extraction   wells,  and/or
adjusting current system operations.  One goal of this  alternative
will be to estimate  the  time  frame  to  reach clean-up  objectives.
This will be facilitated through continued, long-term  performance
monitoring of the site.

The remedial action  objectives and  clean-up goals  for this Final
Remedy are presented in Section VII of this  ROD.   The remedial
action objectives include:

*      Reduction of the  migration of contaminants of concern  from
       the Fill Areas.
*      Reduction of the  concentrations of contaminants of  concern
       in groundwater at the  site to acceptable risk  levels.
*      Reduction of  groundwater concentrations  of contaminants of
       concern at the site  to meet Federal Maximum  Contaminant
       Levels  (MCLs) and State NR 140 Enforcement Standards (ESs)
       and Preventive Action Limits  (PALs) at and beyond the waste
       boundaries (edge  of waste).
*      Return  useable groundwater at the Site  to  beneficial use
       wherever practicable, within a timeframe  that is reasonable
       given the  circumstances of the Site.


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*       Further   evaluation  of   the   groundwater   and  plume
        characteristics  in  the  Non-Contiguous  Fill  Area   and
        downgradient of this area during pilot scale tests.

Table  10  lists a detailed cost  summary for the selected  remedy.
U.S.  EPA  and the  WDNR  believe  that  the  selected  remedy,  in
combination with  the  previous  actions,  will achieve the remedial
action objectives for this remedy.  To the extent additional phases
are  required  upon  implementation  of Alternative 3,  the  present
value  costs of Alternative 3 would  still be significantly lower
than Alternative  4  because:  (1)  expansion of the system would be
deferred  for  several  years,  substantially  reducing  the  present
value of  those costs;  and (2)  contaminant reductions achieved by
the SCOU and operation of  the system in the NCF area  may permit any
later  phases  to  be  more limited  than  what  is anticipated  in
Alternative 4.

X.  STATUTORY DETERMINATIONS

A.      Protection of  Human Health and the Environment
The selected  remedy provides adequate protection of human health
and  the  environment  through  a phased  approach to  groundwater
monitoring, extraction and treatment.   This builds  on previous
response actions which were designed to reduce possible  sources for
additional  contamination  of  groundwater  and  to  limit  direct
exposure to contamination.

As described  in the SCOU  ROD,  the effect of the Site on wetlands
located southeast of  the  Site  have been mitigated through source
controls.   Extracting and  containing  contaminated  groundwater
should provide further protection for those wetlands.

The groundwater operable  unit,  building on the SCOU remedy,  will
attempt to restore  groundwater to the State ESs and  PALs and to
Federal MCLs.

B.      Attainment of  ARARs
The selected  remedy will  be designed to  meet  all  applicable,  or
relevant and  appropriate  requirements (ARARs)  under federal,  and
more stringent state environmental laws.  A list of ARARs  for the
site is contained in the alternative arrays section of the FS.  The
primary ARARs that  will"be achieved  by  the selected alternative
are:
        1.    Action  Specific

Resource Conservation and Recovery Act,  as amended  [42  U.S.C.
S 6901 at seq.]; Wisconsin Environmental Protection Law, Hazardous
Waste Management Act  [Win. Stat. 5 144.60-74]
Most  RCRA  requirements  are  administered  under  the  State  of
Wisconsin's  implementing  regulations.   U.S.  EPA  does not have

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sufficient  evidence to demonstrate that  listed  RCRA wastes were
disposed  of at  the site.   RCRA requirements are  therefore not
applicable  to  the site, except to  the  extent that new hazardous
wastes  (such as  treatment  residuals)  are generated  during the
course of the remedy.   Several other RCRA regulations, although not
applicable, address problems or circumstances very similar to those
encountered  at   this  site  and   are   therefore  relevant  and
appropriate.  However,  the remedy will  comply with the following
applicable requirements:

Wis. Admin. Code NR 605; 40  CFR 261 - Identification of Hazardous
Wastes.   Provides  requirements  for determining when  a waste  is
hazardous.  The substantive requirements of these regulations will
apply to any on-site TCLP testing of treatment residuals and waste
excavated at  the site  (e.g. in constructing  wells)  which  may be
disposed of off-site.

Wis. Admin.  Code NR  615;  40 CFR  262 -  Standards  Applicable  to
Generators  of Hazardous  Waste.    Provides requirements for the
shipment of wastes  to treatment,  storage or disposal facilities.
These requirements  may  apply to on-site preparations for off-site
shipment of treatment residuals and other wastes.

Wis. Admin.  Code NR 620;  Department  of Transportation Hazardous
Materials Transportation Act  [49  U.S.C.  § 1801];  40  CFR  263  -
Standards Applicable to Transporters of  Hazardous Waste.  Requires
record  keeping,   reporting and manifesting  of waste  shipments.
These requirements  may  apply to on-site preparations for off-site
shipment of treatment residuals and other wastes.

Wis. Admin.  Code NR 630.10-17; 40  CFR  264,   Subpart B -  General
Facility Requirements.   Establishes substantive  requirements for
security, inspection,  personnel  training,  and materials handling
which are relevant and appropriate to  on-site  activities involving
excavations and handling of  hazardous soils and materials.

Wis. Admin.  Code NR 630.21-22;- 40  CFR  264,  Subpart D - Contingency
Plan   and  Emergency  Procedures.      Establishes   substantive
requirements  for   emergency planning  which  are  relevant  and
appropriate  for  on-site  activities  involving  excavation  and
handling of hazardous substances.

Wis. Admin. Code NR 675; 40  CFR 268 - Land Disposal Restrictions.
Requires that hazardous wastes cannot  be land  disposed unless they
satisfy specified treatment  standards and imposes record  keeping
requirements on such wastes.  These requirements apply to on site
activities related  to off-site disposal of any treatment residues
or other hazardous  wastes.

Clean Water Act of  1977, as  amended [33 U.S.C. 5 1317]
40 CFR 403  - Pretreatment  Standards.  To the extent waste  waters
will be discharged  into a Publicly  Owned Treatment Works  (POTW) ,

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the  selected  remedy  would  satisfy  both  general  and  specific
requirements to protect against damage to POTWs.   Any waste to be
discharged to  a POTW  must,  if necessary, be  treated to satisfy
these   standards   prior   to   discharge.     These  pretreatment
requirements  are  administered  under  NR  211  and 108.    The
substantive  requirements  of  these  regulations  will   apply  to
collected groundwater  to be discharged.

        2.    Chemical Specific

Clean Air Act  [42 U.S.C. S 7401 et seq.]; Wisconsin  Environmental
Protection Law, Subehapter Ill-Air  Pollution [Wis. Stat. 144.30-
144.426]
40 CFR 50;  Wis. Admin.  Code NR  404, 415-449 - Emissions Standards.
Establishes standards  for emission of pollutants into the ambient
air  and  procedures   for  measuring  specific  air  pollutants.
Groundwater treatment  or pretreatment may require  removal of VOCs
before discharge.  The  need for treatment of air emissions produced
by  this  process   would  be  evaluated based  on  substantive
requirements of Wis.  Admin. Code NR 445.  If emissions are expected
to  exceed  those  standards,  the  selected  remedy  will  include
treatment of air emissions. Handling of  contaminated soils during
excavation could also  cause air  emissions of VOCs, particulates,
fugitive dust or other contaminants  which could adversely effect
human health and the environment.   The design of the remedy will
reduce such emissions to acceptable levels or provide  for treatment
to satisfy these standards.

Safe Drinking Water Act [40 U.S.C. S 300 et seq.]
40 CFR 141, Wis. Admin. Code NR  109  - Maximum Contaminant Levels
(MCLs) .  MCLs establish drinking water  standards  for potential and
actual drinking water sources.  MCLs have been exceeded at the site
in the shallow aquifer, which is classified as a potential drinking
water source.  The selected remedy, building on the  SCOU remedy, is
intended to  achieve  compliance  with  MCLs  and  non-zero Maximum
Contaminant Level Goals.

Wis. Admin. Code NR 140 - Groundwater Quality Standards.  Provides
for  groundwater quality  standards  including Preventive  Action
Limits  (PALs),  Enforcement  Standards   (ESs),  and  (Wisconsin)
Alternative Concentration  Limits  (WACLs).  The  selected remedy,
building on the SCOU remedy, is intended to achieve  compliance with
PALs at and  beyond the waste  boundary (edge of waste) .   To the
extent it is subsequently determined that it is not technically or
economically  feasible to achieve   PALs,   NR  140.28  provides
substantive standards for granting exemptions  from  the requirement
to achieve  PALs.  Such exemption  levels may not be  higher than the
ESs.

Discharge to an infiltration basin would meet ch.  NR 220, Wis. Adm.
Code, WPDES Best Available Technology (BAT)  requirements, at the
point of discharge  and ch. NR 140,  Wis.  Adm.  Code,  PALs for all

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contaminants  in the  groundwater at  a  point directly below  the
discharge zone.  To the extent it is  subsequently determined that
it is not technically or economically feasible to achieve PALs,  NR
140.28 provides substantive standards for granting exemptions from
the requirement to achieve PALs.   Such exemption levels may not be
higher than the ESs.


Resource  Conservation and  Recovery Act,  as amended   [42  T7.S.C.
S 6901 et aeg.]; Wisconsin Environmental Protection Law,  Hazardous
Waste Management Act  [Win. Stat. § 144.60-74]
Most  RCRA  requirements  are  administered  under  the  State  of
Wisconsin's  implementing regulations.   U.S. EPA  does  not  have
sufficient evidence  to demonstrate that  listed RCRA wastes  were
disposed  of  at the site.   These RCRA  regulations,  although not
applicable, address problems or circumstances very similar to those
encountered   at   this  site  and  are   therefore   relevant  and
appropriate.

Wis. Admin. Code NR 635.09; 40 CFR 264.94 - Concentration  limits.
Establishes  concentration  limits  in  groundwater  for  certain
hazardous  constituents related  to  a hazardous  waste management
unit.

40 CFR 265.1032-33 - Air emissions standards for process vents.
Establishes   emissions  standards   for  certain  air  stripper
operations.  If air stripping is used to  remove VOCs from extracted
groundwater, air stripper emissions would meet applicable standards
under  these  regulations.    As  with  the Clean Air Act  standards
described above,  treatment of these air stripper  emissions would be
included if necessary to meet RCRA air emission standards.

Wisconsin Environmental  Protection Law,  Subchapter  IZ-Water and
Sewage  [Wis.  Stat.  § 144.02-27];  Clean  Water  Act  of  1977, as
amended [33 U.S.C. S 1311-17]
Wis. Admin. Code NR 102 and 105 - Surface water quality standards.
NR 102  creates an antidegradation policy for all waters  of the
State  and  prohibits  toxic  substances  in  surface  waters  at
concentrations which  adversely affect public health or welfare,
present or prospective water supply uses, or protection of animal
life.   The selected  remedy,  building  on the SCOU  remedy, will
achieve   compliance   any   substantive   requirements   of   these
regulations that constitute ARARs for discharge into the retention
pond on-site,  including ch. NR.  220,  Wis. Adm.  Code,  WPDES Best
Available Technology (BAT)  requirements, at the point of discharge
and ch. NR 140,  Wis. Adm. Code, PALs  at  a point directly below the
discharge zone.  To the extent it is subsequently determined that
it is not  technically or economically feasible to achieve PALs, NR
140.28 provides substantive standards for granting exemptions from
the requirement to achieve  PALs.  Such exemption levels may not be
higher than the ESs.


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40 CFR 131 - Ambient Water Quality Criteria.  Establishes pollutant
concentration  limits  to protect surface waters.  These and other
water  pollution  discharge  limits  are  administered under  the
Wisconsin  Pollutant  Discharge  Elimination System (WPDES) permit
program.    The selected remedy would  satisfy both  general  and
specific, substantive requirements for discharge to on-site surface
waters, namely the retention basin.  Any waste to  be discharged to
a surface  water must, if necessary,  be treated to satisfy these
standards  prior to discharge.   These treatment requirements are
administered under NR 200 and 220.  The substantive requirements of
these  regulations will apply  to  collected  groundwater to  be
discharged.   The source control remedy is intended  to eliminate
contaminated   surface   runoff   at   the  site.    To  the  extent
contaminated runoff is channeled directly to a surface water body,
however, that runoff must comply with any applicable concentration
limits.

        3.   Location Specific

Clean Water Act of 1977, as amended  [33 U.S.C. S 1344]
Executive Order 11990 and 40 CFR 6 -  Protection of Wetlands.
Wis. Admin. Code NR  103 - Water Quality Standards  for Wetlands.
These  requirements   provide   for   protection  against  loss  or
degradation of wetlands. Contamination in surface  water runoff and
groundwater will be controlled so that it does not have an adverse
impact on nearby wetlands.

C.      Cost Effectiveness
The selected remedy  provides  overall cost-effectiveness.   Phased
extraction that focuses  on the most  highly contaminated groundwater
first adds a significant degree of permanence, as well as a further
opportunity to assess  the  effectiveness  of  the  SCOU remedy  in
reducing new contaminant loadings in groundwater.  Thus, the effect
of  these  remedial  activities  on  compliance  with  ARARs   and
protection  of  human  health and the  environment will  be  analyzed
before requiring a broader, more costly groundwater extraction and
treatment system.

D.      Utilization  of  Permanent  Solutions  and   Alternative
        Treatment Technologies  to the Maximum Extent Practicable
The  selected   alternative  represents   the  best   balance   of
alternatives with respect to the nine evaluation criteria described
in Section VIII.  The selected alternative adopts a phased approach
to  address groundwater contamination,  extracting  and  treating
contamination that exceeds regulatory standards.

E.      Preference for Treatment As A Principal Element
By  extracting  and treating  the  contaminated groundwater,   the
selected remedy  satisfies  the statutory  preference for  remedies
that employ treatment as a principal  element to  permanently and
significantly  reduce  toxicity,  mobility,  or  volume of hazardous
substances.

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XI.  RESPONSIVENESS SUMMARY

This  Responsiveness  Summary  has  been  prepared   to  meet  the
requirements  of  Sections  113 (k) (2) (B) (iv)  and  117 (b)  of  the
Comprehensive Environmental Response,  Compensation,  and Liability
Act  (CERCLA) of  1980,  as amended by the Superfund Amendments and
Reauthorization  Act  (SARA)  of 1986,  which requires U.S.  EPA to
respond  "...to  each of  the  written or  oral  presentations"  on a
Proposed Plan  for remedial action.   This Responsiveness Summary
summarizes comments and concerns  expressed by the public and other
interested parties in written and oral  form received by U.S. EPA on
the recommended remedy.

On October  3,  1994, U.S.  EPA made  available to the public for
review and comment the  FS and Proposed Plan for groundwater at the
Muskego Sanitary Landfill.  This comment period was extended for 60
days until December 2,  1994..

U.S.  EPA received comments  at  the public  meeting on October 17,
1994, at the Muskego City Hall.  Additional written  comments were
also submitted during the comment period.

                                               Cormi|ent Period

Comments received during the public comment, period are summarized
in this  section.   Some of the comments have  been paraphrased in
order to effectively summarize them in this document.  The reader
is referred to the public meeting transcript and  copies of written
comments  submitted.    All  are  available  for  review  at  the
information repositories.

Comment;    One  commenter  believes  Alternative 2,  Groundwater
Monitoring,   will  provide  protection  to  human  health  and  the
environment and therefore is a viable alternative.

The commenter stated that the previous  removal  actions and source-
control measures,  coupled  with natural  mitigating  processes are
expected to limit further groundwater contamination  and result in
a reduction of groundwater contaminant concentrations from those
identified in the Remedial Investigation Report  (RI) .

The  commenter  views that  in order  to  effectively  evaluate  the
impact of the  SCOU activities on  groundwater there needs  to be
adequate time  after completion  of  these  activities to  monitor
groundwater contamination.  In  addition,  nearby private residences
have been  connected to  public water  supplies  and  institutional
controls that prohibit  private well installation within 1200 feet
of an existing landfill are in effect.  The  commenter  believes that
these conditions  preclude the hypothetical exposure associated with
the potential future use  of the site and therefore Alternative 2 is
a viable remedial option for this site.


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U.S. EPA Response:  U.S. EPA agrees that the previous removal and
SCOU activities will have a positive effect on groundwater quality
in the vicinity of this site.  U.S. EPA believes  these actions will
contribute  to  the reduction  of  contaminant  loading  into  the
groundwater  and coupled with  natural mitigating  processes will
reduce contamination levels in groundwater.  However, given the age
and design characteristics of the source areas and the high level
of contamination  in the groundwater near the Non-Contiguous Pill
Area, U.S. EPA does not believe  that these actions will adequately
address  threats  posed  by  the  existing  contamination in  the
groundwater nor completely eliminate additional contaminant loading
into the groundwater.

The State prohibition on the installation of drinking water wells
within  1,200  feet of the  edge  of   waste may not  always  be
effectively enforced,  since it  is dependent on the well driller or
property owner contacting the  WDNR prior to well  installation.
Also, the WDNR can grant variances from the prohibition,  so the
prohibition  is not absolute,   even   if  the WDNR is  contacted.
Therefore, the effectiveness of  institutional controls relating to
water supply well prohibition is dependant upon the site owner or
contractor contacting  the WDNR,  and is not  absolute,  even  if the
WDNR is contacted.

U.S. EPA  also  agrees  that  one  of the  objectives  of  a  phased
approach to this remedy is  to gather additional information on the
effect of the previous  remedial activities at the site.  However,
regardless of current risk or hypothetical future use scenarios of
the landfill property,  one of the objectives  of this final remedial
action is to determine how to effectively prevent or  retard the
migration of contamination already within the aquifer  which will
not be affected by SCOU actions.  U.S.  EPA believes  that  prior
actions in combinations with natural processes may be effective in
the outer limits of the plume beyond the source areas but, does not
believe natural mitigating processes will be effective in areas of
higher contamination near a source, such as the Non-Contiguous Fill
Area.    Therefore  U.S. EPA disagrees  with  the  comment  that
Alternative 2 is a fully protective alternative.  For that reason,
the remedy initially targets only the  source area with the highest
levels of  contamination.   This provides adequate  time, as  the
commenter suggests, to  evaluate the impact of clean-up activities
on other areas of the site.


Comment:   One commenter believes that  Alternative 3,  if selected,
should be implemented  in a phased approach  to gain the necessary
data  to  determine the progress  towards,  and probability  of,
actually  achieving  clean-up objectives.    The  commenter  also
believes that a comprehensive pilot scale test be included in the
Alternative   with  the  purpose  of  determining   groundwater
characteristics and evaluating  discharge and treatment  options.
The commenter has  indicated that an evaluation of the effectiveness

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of  groundwater  extraction  in  capturing  contaminants  and the
potential for achieving groundwater clean-up objectives  should be
performed during  the  pilot test phase.   Also  a mechanism to re-
evaluate  the  need for  further groundwater extraction should be
provided  if necessary.   Finally, the  commenter believes that if
results  from  the evaluation process  indicate that  only if the
groundwater extraction will  achieve  these objectives and natural
attenuation is  ineffective in achieving  the objectives should a
long-term limited .pump and treat system be installed and  operated.

U.S.  EPA Response:   U.S.  EPA  agrees with  the  commenter that
Alternative  3  should be  implemented  in a phased  approach  to
accomplish the objectives associated with this  ROD.   U.S.  EPA also
believes that a pilot  scale study should be completed as  indicated
in  the  description  of Alternative  3.   A Performance Evaluation
Report will be required that evaluates groundwater characteristics,
discharge and treatment options as well as other parameters.  This
study  will,   as  the  commenter suggests,  be   used  to  design  an
effective  system.   In  addition, a  mechanism  to  evaluate the
progress toward achieving the groundwater  clean-up  objectives not
only during the pilot scale  test but during an extended duration
will be required.

U.S.  EPA does  not  agree with the  suggestion that  only  if the
groundwater extraction  system is proven effective  and natural
attenuation is proven  ineffective in  the pilot  test  should a  long-
term limited pump and  treat system be installed.  Groundwater pump
and  treat  systems  are   effective   in removing  and containing
contamination.  The pilot test  is aimed at optimizing the  design of
a system, not to  demonstrate the need for one.  The ROD and the
underlying documents demonstrate the  need and show that the system
will move the  site toward achieving groundwater clean-up standards
and   addressing  unacceptable   levels  of  contamination   more
expeditiously.


Comment:  One commenter who  lives near the site would like their
private well sampled for Volatile Organic Compounds.

U.S. EPA  Response:   Private wells  near the site,  including the
commenter's well, were sampled in August 1991 by U.S. EPA.  There
was no contamination found during this sampling round in any of the
wells.   Groundwater monitoring  since 1991 has not  indicated  a
change in groundwater contamination levels, therefore there  is no
reason to believe that contamination would have reached this well
from the site.  In addition,  all  residences in  the vicinity of the
site have  been connected to public  water thereby  eliminating  a
concern for potential exposure through ingestion.   U.S. EPA has
provided this comment  to the State authorities and recommends the
commenter contact the  local WDNR office for further  information on
procedures for private well sampling.


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Comment:  One commenter stated that all private and monitoring well
results of all tests taken on her property be forwarded to her.

U.S.  EPA  Response:   U.S.  EPA will ensure that  sampling results
related to the  commenter's  property from the Interim Groundwater
Monitoring Plan will be forwarded to the commenter as these results
become available. Additional information regarding test results is
available at  the information  repositories  located at the Muskego
City Hall and the Muskego Public Library.


Comment:  One commenter from the City of Big Bend provided U.S. EPA
with  sampling information provided  to him by the  WDNR  for  his
business.  The  commenter  expressed concern for citizens  that are
not on public water and what is being done for them.

U.S.  EPA Response:    U.S.  EPA  thanks  the   commenter  for  this
information.   If more information  is needed,  the  Agency  will
certainly contact him.  The  site  currently  does not  impact  any
private drinking wells in  the City  of Big  Bend.   All  private
residences near  the  site  have been connected  to  public water.   A
few residences  retained  their private well for  non-potable  uses
such as watering their gardens and yard.


Comment:  One commenter expressed concern that it was unclear how
future public comment  would be incorporated into the process  of
selecting  and   implementing  additional   remedial   actions   for
Alternative 3.

U.S. EPA Response:   p*f>*  EPA  acknowledges  the concern for public
input on  future decisions  regarding  this  project.   Contingency
measures for Superfund projects are described in three categories.
Non-significant  changes,   Significant  changes  and  fundamental
changes to the decision document are the means to make changes to
a selected remedy.  Non-significant changes  are usually adjustments
that relate to design, construction or administrative factors but
do not significantly change or modify the remedy.  These changes do
not  effect   the overall  scope of the  remedy  and  are  usually
documented in the post-decision document file.   This information
can be placed within the information repository at the discretion
of the project manager.

Significant changes  are generally incremental changes described in
a document called an Explanation of Significant Difference (BSD).
These changes are communicated  to the  public through a  public
notice usually published  in one or more of the local newspapers.
In addition,  changes under an BSD are placed  in the information
repository.   The project manager has the discretion to seek public
comment on the ESD.
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Finally, any fundamental change to the remedy would require a ROD
Amendment which requires the agency to open a 30 day public comment
period.   During this period  the  agency would notify  the public
through newspaper  advertisements  and  solicit public  review and
comment on the Amendment.  A public meeting would also be conducted
by the agency during the comment period.
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