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       In 1981, the Pennsylvania Department of Environmental Resources closed the landfill.
From 1983 to 1986, EPA performed an emergency response action which included fencing the
Site, demolishing sheds, removing 75 drums with hazardous liquids, and removing and recycling
clean empty drums. B1984, the Site was listed on the National Priority List EPA completed a
Remedial Investigation/ Feasibility Study in August 1985.

       On May 7,1986, EPA chose a remedy to clean up the Site which includes the following
components:

•      Excavation and consolidation of highly contaminated soil and sediments under a R£RA
       cap;
       Installation of a soil cover over soils containing lower levels of contamination;
       Construction of surface water basins and ditches;
       Revegetation of soil cover and RCRA cap;
       Installation of additional monitoring wells;
       Construction of a flood retention basin; and
       Extraction and treatment of contaminated groundwater..

       To manage the technical aspects of Site remediation, EPA divided the Site into two-   -"'
Operable Units (OUs):

•      OU-1, which includes remediation of contaminated groundwater using an extraction and.
       treatment system; and
•      OU-2, which includes remediation of the contaminated soil and sediments at the Site by
       completing the remaining components of the ROD.

       The design for the groundwater extraction system was initiated hi October 1989 and
completed hi December 1990.  The groundwater treatment system design, including the-
construction of the Millcreek. Treatment Plant (Plant), was completed in January 1992.

       On March 31,1992, EPA ordered the Potentially Responsible Parties (PRPs) to perform
the OU-2 remedial action. Several PRPs are currently complying with the order,

C.    Significant Difference*
                     *
       At the time the ROD was issued, EPA determined that areas of highly contaminated soil
and sediment may be serving as a source for continued migration of contamination to
groundwater; Therefore, the ROD remedy included a component requiring that these areas be
excavated, consolidated, and covered with a multilayer cap in accordance with appropriater
Resource Conseration and Recovery Act (RCRA) requirements. A RCRA cap would reduce
infiltration of surface water into the contaminated soil and sediment and thus prevent leaching of
the contaminants into the groundwater. The ROD required that areas of the Site with
contaminant levels that pose a direct contact threat, but not a threat to groundwater, be graded,

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covered with clean soil, and revegetated to prevent potential exposure with the contaminants.
       When the remedy was selected, EPA did not define the level at which soil and sediment
contamination would"pose a threat to groundwater and, therefore, trigger excavation,
consolidation, and covering of these materials with a RCRA cap. This level was to be established
after additional studies were completed including extensive field sampling and fate and transport
modeling to determine distribution of Site contaminants. However, additional soil sampling
revealed that contaminants are distributed throughout the Site and do not occur in concentrated
areas that can be readily excavated and consolidated as anticipated at the time the ROD was
issued.

       Volatile organic compounds are widely distributed in the northeast, central and south
central portions of the Site; semi-volatile organic compounds (SVOCs) are present in virtually
all the soif samples collected in the northeast, southwest, and central portions of the Site;
polychlorinated biphenyls (PCBs) occur in both the southeast and central portions of the Site,
and inorganic trace elements are detected in concentrations greater than background throughout •
the entire thickness of the fill material at the Site. Elevated concentrations of volatile organic
compounds (VOCs), including xylenes up to 1,600 parts per million (ppm) and ethyl benzene up>
to 1 SO ppm, are associated with a location where a soil sample was collected from beneath a~ ..,;
buried drum. However, the  majority of the VOC samples have concentrations below 0.1 ppnr Jf
PCBs were detected in approximately 10 percent of the soil samples with the highest
concentration being 18 ppm. Most of the soil samples-had PCB concentrations below 0.1 ppm.

       Because some soil samples did exhibit high levels of contamination, EPA evaluated
whether a RCRA cap should be required for the entire contaminated area to prevent further
migration of contaminants to the groundwater. Modeling was conducted as part of the Remedial
Design to evaluate the impact that various types of caps would have on contaminant migration.
Contaminants are present in groundwater at die Site through several transport mechanisms. The
shallow water table actually extends into the fill areas. Therefore, contaminants are in direct
contact with the groundwater and transported by the flow of the groundwater itself. A RCRA
cap would not alter this tninsrwr^echanismliecause groundwater flow Is not significantly
affected by infiltration at thja Site. Contaminants in the unsaturated zone above the water table
are primarly transported to the groundwater by infiltration of surface water. A RCRA cap would
almost completely eliminate further migration of contaminants resulting from infiltration.
However, the modeling demonstrated that the contaminant loading from the unsaturated zone-
was relatively low in comparison with the levels of contamination already existing in the
groundwater. Contaminants which previously migrated from the unsaturated zone or continue to
migrate from waste material in the saturated zone are much more significant sources. Therefore,
constructing a RCRA cap over the entire contaminated areas would not significantly reduce the-
contaminant loading or the time required for groundwater remediation^

       Based on the findings of the post-ROD studies, EPA has determined that the ROD
component requiring excavation, consolidation, and capping of highly contaminated soil and

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sediment should be deleted. Rather, EPA is requiring that areas of contamination identified in
the remedial design, approximately 50 acres, be covered with a 12-inch soil cover.  In addition,
EPA is requiring that a warning sheet (i.e., a geotextile fabric) be placed on top of the graded
contaminated areas prior to placement of the soil cover. This requirement is in response to a
PRP request that EPA evaluate future use of the Site as a golf course. The warning sheet would
allow this use and provide a mechanism to ensure that the contaminated soil beneath the soil
cover is not inadvertantly brought to the surface where those using the Site for recreational
purposes could be exposed. The soil cover will also be graded to accommodate potential future
recreational development of the Site to the extent possible within the limits of State
requirements.

       EPA has determined that the remedy modification documented in this ESD is protective
of human health and the environment The soil cover will eliminate direct contact risks at the
Site by isolating the soil contaminants to prevent air dispersal and erosion and surface water
transport The remedy remains protective of groundwater at the Site because soil and sHirpgnt
contaminants are not present at levels that pose a threat to groundwaten.

D.     Affirmation of Statutory Determination*

       Considering the new information that has been developed, EPA has determined that the*
remedy, as modified by this ESD, remains protective of human health and the environment,
complies with Federal and State requirements that are applicable or relevant and appropriate to
this remedial action, and is cost-effective.

E.     Support Agency Comments.

       The above modifications to the remedy have been made pursuant to 40 CJJL §
300.435(cX2XD and hi coordination with representatives of PADEP.

F.     Public Availability

       EPA invites the public to review and comment on mis ESD as part of the Agency's
decision-making process regarding remediation of the Site. The ESD is available for review as
part of the Administrative Record for the Site at the two locations identified below:

             U.S. Environmental Protection Agency
             Region m
             841 Chestnut Building-
             Philadelphia, Pennsylvania 19107
            .(215)566-3157
             Hours: 8:30 aon. to 5:00 p.m.
             Monday through Friday

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             Millcreek Township Building
             3608 West 26th Street
             Erie, PA 16505
             Contact: Roseanne Eckerson
             (814)133-1111
Interested parties may comment during a 30-day public comment period that begins on May 14,
1997, and closes on June 13,1997. Written comments, postmarked no later than May 18,1997,
should be sent to the following address:.

            Romuald A. Roman (3HW22)
            Remedial Project Manager
            841 Chestnut Building
            Philadelphia, Pennsylvania 19107
            (215)566-3212
  lomas C. Voltaggio, Director
Hazardous Waste Management Divisii

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              UNITED STATES ENVIRONMENTAL PROTECTION AGENCY
              _               REGION HI
                          841 Chestnut Building
                      Philadelphia, Pennsylvania 19107

Office of Superfund                                  Direct Dial (215) 566-3212
Romuald A. Roman, CIH
Remedial Project Manager          .                      Mail Code 3HW22
                                              December 3, 1996
Wayne F. Barto
Project Director
de maximis, inc
301 Gallaher View Road
Suite 227
Knoxville, TN 37919
RE:      Millcreek Dump Site,  OTJ - 2 - The alternative site use


Dear Mr. Barto:

     EPA hereby presents  its comments pertaining to the de
maximis letter, dated November 15, 1996,  and following this
letter fax- message,, dated November 18,  1996.

Both documents discuss the repercussions of the meeting of
November 7, 1997, during  which the Group presented to EPA a
concept to modify the EPA's approved Remedial Design
documentation for the Operable Unit 2 (OU-2). According to the
Group the requested modification would expedite the process of
obtaining permanent easements  from Millcreek Township and Cbnrail
and create a new recreation facility for Millcreek County.

Please be reminded that the on-site construction of the OU-2 has
been scheduled.to start in the Spring of 1996.  Unfortunately,
even though EPA assisted  the Group by issuing easement request
letters in December 1995, the  construction has not started
because the Group has not obtained permanent easements from
Milcreek Township and Conrail. This easements issue was discussed
recently between counsel  Mark  Shaw and EPA Ass. Regional Counsel
Benjamin Cohan during a teleconference dated 11/20/1996.  During
this teleconference, it was agreed that holding the 15 & 17th
street access issues "hostage" to the approval of the alternative
use for the site served no construction purpose and that
therefore, all access agreements will be executed before or at
the time the Conrail access is obtained.   It was further agreed
that EPA and the Group do not  want this alternative use issue to
impede the anticipated construction start date for ou-2.  To that

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j   end, and in order to provide EPA with the time it will require to
/    provide an adequate analysis of your proposal, we are requesting
     that you submit the above documentation to the undersigned by or
     before 01/30/97 date.

     The concept of an"alternative use of the site for a golf course
     generally follows EPA's policy to maintain and use Superfund
     sites for the best benefit of the nearby population. However
     interesting this new concept is, EPA cannot automatically approve
     the modification until the details of this proposal are
     thoroughly evaluated. The crucial parts of the documentation
     which must be submitted to EPA include:

     1.   Revised drawing and specifications of the cap and
     evaluation, which must include its potential impact on surface
     water- groundwater interactions, modified water levels in
     extraction trenches, and modified flow rates in Marshall's Run.

     2.   Revised design of the storm water control and disposal
     system,  including the design of cap drainage system, and re-
     evaluation of 1995 computer modeling and design of the flood.
     retention basin.  The presented cap modification must not lead to
     the increase of flooding hazards.

     3.   Evaluation of potential impact of.the proposed cap
     modification on the efficiency of the .treatment plant
     performance.  Specifically, this evaluation must state whether
     the installation of the impermeable layer, modification of
     slopes,  and modification of storm water control and disposal
     would improve or decrease the efficiency of the treatment plant,
     which captures contaminated groundwater from the entire area of
     the site.

     4.  The accessibility of the golf course to the general public.

     5.  PADEP's waiver of the 3 percent grade requirement for the
     cap.
             t
     6.  Proposed documentation submission schedule.


                                             Sincerely,


                                             Romuald A. Roman, CIH
                                             Remedial Project Manager
     cc:
     Ed Orris  •
     Gary Lang
     Gregg Crystal
     Ben Cohan
     Mark Shaw,  Esq.
     Evan Adair, Esq.

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