United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R05-87/049
September 1987
Superfund
Record of Decision:
 Northside Sanitary Landfill/
 Environmental Conservatioh
 and Chemical, IN

-------
                                    TECHNICAL REPORT DATA
                             /Please read Instructions OH the revtne before completing)
 1. RiPORTNO.
 EPA/ROP/RQ5-87/049
             3. RECIPIENT'S ACCESSION NO.
 4. TITLE AND SUBTITLE
 SUPERFUND RECORD OF  DECISION
 Northside Sanitary LF/Enviro-Chem., IN
 First Remedial Action     	
             5. REPORT DATE
                       September  29,  1987
             6. PERFORMING ORGANIZATION CODE
 7. AUTMOR(S)
                                                            8. PERFORMING ORGANIZATION REPORT NO.
 9. PERFORMING ORGANIZATION NAME AND ADDRESS
                                                             10. PROGRAM ELEMENT NO.
                                                             11. CONTRACT/GRANT NO.
 12. SPONSORING AGENCY NAME AND ADDRESS
 U.S.  Environmental  Protection Agency
 401 M Street, S.W.
 Washington, D.C.   20460
              13. TYPE OF REPORT AND PERIOD COVERED
              	Final ROD  Report
              14. SPONSORING AGENCY CODE

                       800/00
 IS. SUPPLEMENTARY NOTES
 6. ABSTRACT
    The Northside Sanitary Landfill (NSL) and  the  Environmental Conservation  and Chemical
 Corporation (ECC)  are adjacent sites located  in Boone County, Indiana.  These  two sites
 have been combined into the first remedial action because of their close proximity, and
 due to similarities  in contaminants, affected media,  remediation needs and regulatory
 status.  Between 1977 and 1982, ECC was involved  in the recovery/reclamation/brokering
 of primary solvents,  oils and other wastes received from industrial clients.   Waste
 products were  received in drums and bulk tankers  and prepared for subsequent reclamation
 or disposal.   Onsite accumulation of contaminated stormwater, poor management  of drum
 inventory and  several spills prompted State and U.S.  EPA investigation of ECC.   Between
 1977 and 1981  some still bottom and oily liquid wastes were permitted to be  disposed of
 at NSL.  In May 1982, ECC was ordered by the  court to close and environmentally secure
 the site for failure to produce hazardous waste inventories.  Two emergency  actions in
 March 1983 and March 1985 eliminated the major sources of contamination at the site.
 Soils on site  contain high concentrations of  organic compounds including trans-l,2-DCE,
 trichloroethene, 1,1-DCE and vinyl chloride.   The possibility exists for the presence of
 other sources  of contamination at the site.
 (See Attached  Sheet)
17.
                                KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
                                               b.lOENTIFIERS/OPEN ENDED TERMS
                           c.  COSATI Field/Croup
 Record of Decision
 Northside Sanitary LF/Enviro-Chem., IN
 First Remedial Action
 Contaminated Media:  soil, sediments, gw,  sw
 Key contaminants:  VOCs,  TCE, organics,
  inorganics, pesticides, oils
 8. DISTRIBUTION STATEMENT
19. SECURITY CLASS (This Report!
          None
21. NO. OF PAGES
           105
                                               20. SECURITY CLASS (Tliispaget
                                                                          22. PRICE
BPA F«rm 2220-1 (R«v. 4-77)    PNKVIOUS COITION i* OBSOLCTK

-------
                                                        INSTRUCTIONS

    1.   REPORT NUMBER
        Insert the I PA report number as it appears on the cover of the publication.

    2.   LEAVE BLANK

    X   RECIPIENTS ACCESSION NUMBER
        Reserved for use by each report recipient.

    4.   TITLE AND SUBTITLE
        Title should indicate clearly and briefly the subject coverage of (he report, and be displayed prominently. Set »uhiitlc. if used, in l. 1'rescntcd at conieremi- -•!.
        To be published in. Supersedes. Supplements, etc.

    IB.  ABSTRACT
        Include a brief (200 words or Ita) factual summary of the most significant information contained in the rc|x>ri. Il the report mutants j
        significant bibliography or literature survey, mention it here.

   17.  KEY WORDS ANO DOCUMENT ANALYSIS
        (a) DESCRIPTORS • Select from the Thesaurus of Engineering and Scientific Terms the proper auihori/cd term* thai  identity the major
        concept of the research and are sufficiently specific and previse to be used as index entries lor (.atalopinf:.

       (b) IDENTIFIERS AND OPEN-ENDED TERMS * Use identifiers for project names, cude names, equipment JcMjinatorv etc. live open-
        ended terms written in descriptor form for those subjects for which no descriptor exists.

        (c) COSATIIILLD GROUP • Held and group assignments are to be taken from the 1965 COSATI Subject Caie«niry List. .Since the ma-
       jority of documents are multidtscipiinary in nature, the Primary Held/Group amignmenifs) will be \ix-uiu discipline, area of human
        endeavor, or type of physical object. The application^) will be cros»-reiercnced with \ei-undary I ielil/(.roup jsM^mnenis that will l
        the primary posting!*).

   IB.   DISTRIBUTION STATEMENT
        Denote releasabilily to the public or limitation for reasons other than security for example "Release I'lilmnieil." f He any jvuilululiiy t
        the public, with address and price.

   19. ft 20.  SECURITY CLASSIFICATION
        DO NOT submit classified reports to the National Technical Information service.

   21.   NUMBER OF PAGES
        Insert the total number of pages, including this one and unnumbered pages, but exclude distribution list, il any.

   22.  PRICE
        Insert the price  set by the National Technical Information Service or the Government Printing Office, if known.
      o
EPA Perai 2220.1 (Rev. 4-77) (*•«•*••>

-------
EPA/ROD/R05-87/049
Northside Sanitary Landfill/Environmental
Conservation and Chemical Corporation, IN
First Remedial Action

16.  ABSTRACT (continued)


   Sometime between 1955 and 1962, NSL began landfill operations.  From 1972 to 1973,
numerous operational deficiencies, including failure to cover refuse, surface burning,
underground fires, leachate and vermin problems resulted in three Indiana State Board of
Health (ISBH) orders to cease operations*;  Operations were permitted at the site by
February 1975.  By November 1982, NSL had accepted at least 16 million gallons of
hazardous substances.  Ground water, surface water, soil and sediments are contaminated
with inorganics, organics, pesticides, acids, base-neutral compounds, oils and VOCs
including benzene, 1,1-DCE and TCE.

   The recommended alternative for the two sites combined includes:  implementing deed
and access restrictions to prevent future site development; excavation and dewatering of
4,200 yd^ of leachate soils and sediments with onsite disposal under a RCRA
multi-layer cap; soil capping on non-RCRA capped areas; site grading; demolition of
former ECC process building followed by capping; re-routing of surface waters; leachate
collection and treatment at NSL; and ground water collection and onsite treatment for
both sites.  The estimated present worth cost for this remedial action is $33,900,000.

-------
                            RECORD OF  DECISION
                      REMEDIAL ALTERNATIVE SELECTION
Site:  Environmental Conservation and Chemical  Corporation,  and
       Northslde Sanitary Landfill, Zionsville, Indiana
Documents. Reviewed
The following documents, which describe the physical  characteristics  of
the Environmental Conservation and Chemical Corporation,  also  referred
.to as the Enviro-Chem Corporation, or ECC,  and  Northside  Sanitary Landfill
(NSL) sites, and which analyze the cost-effectiveness of  various remedial
alternatives, have been reviewed by U.S. EPA and form the basis  for
this Record of Decision (ROD):
     -  "Remedial Investigation Report, ECC Site",  CH2M Hill,  March  14,
        1986.
     -  "Remedial Investigation Report, Northside Sanitary Landfill,"
        CH2H Hill, March 27, 1986, as amended on June 18, 1986.
     -  'feasibility Study, ECC Site", CH2M Hill, December 5,  1986.
     -  Teas1b1l1ty Study, Northside Sanitary  Landfill", CH2M Hill
        December 5, 1986.                                                *:
     -  "Combined Alternatives Analysis Report, Northside Sanitary        I
        Landfill and Environmental Conservation and. Chemical Corporation",*
        CH2M H111, December 5, 1986.                            .         v-
     -  Summary of Remedial Alternative Selection.
     •  Community Relations Responsiveness  Summary.
     -  Partial Consent Decree, dated September 21, 1983.
     -  Other Documents as shown in the Index of the  Administrative  Record.
Description of Selected Remedial Alternative
The selected remedial alternative 1s ground water Interception and treat-
ment plus capping, and Includes the following major components:
     - Deerf and access restrictions to prevent  future development
    '   of the sites*
     • A n»ltt-layer cap over both sites which  meets  the  requirements of
       the Resource Conservation and Recovery Act.
     - Re-routing surface waters to reduce  potential  for  contaminant
       movement to surface water.
     - Leachate collection and treatment for NSL.
     - Ground water collection and treatment for both sites.
     - Monitoring to ensure effectiveness of remedy components listed
       above.

-------
                                 -2-
Conslsteot with the Comprehensive Environmental Response, Compensation
and Liability Act of 1980 (CERCLA), as amended by the Superfund Amend-
ments and Reauthor1zat1on Act of 1986 (P.L. 99-499)(SARA), and the
National 011 and Hazardous Substances Pollution Contingency Plan
(NCP), 40 CFR Part 300, I have determined that, at the Enviro-Chem
Corporation and Northside Sanitary Landfill Superfund sites, the
selected remedial alternative 1s cost-effective, consistent with a
permanent remedy, provides adequate protection of public health,
welfare and the environment, and utilizes treatment to the maximum
extent practicable.

The State of Indiana has been consulted and concurs with the selected
remedial alternative.

The action will require operation and maintenance activities to ensure
continued effectiveness of the remedial  alternative as well  as to en-
sure that the performance objectives meet applicable State and Federal
surface and ground water quality criteria.

I have determined that the action being taken 1s consistent with Section
121 of SARA, 42 U.S.C. Section 9621.
                                                                   «
In accordance with Section 121(c) of SARA, the remedial action taken at  '
Enviro-Chem Corporation and Northside Sanitary Landfill shall  be reviewed
no less often than every 5 years after the Initiation of such remedial
action to assure that human health and the environment are being
protected by the remedial action being Implemented.
valdas v. Adanftjs
Regional Adarinl
Date
              (1) SuMary of Remedial Alternative Selection
              [2j COMunlty Relations Responsiveness Summary

-------
              SUMMARY OF REMEDIAL ALTERNATIVE SELECTION
    ENVIRO-CHEM CORPORATION AND NORTHSIOE SANITARY LANDFILL  SITES,
                         ZIONSVILLE, INDIANA


I.   Location and Description - ECC and NSL

     The Env1ro-Chem Corporation (also referred to as Environmental
     Conservation and Chemical  Corporation, or ECC) and Northside
     Sanitary Landfill (NSL) are both on the Superfund National
     Priorities List, and are adjacent to each other.   During  the
     course of U.S. EPA's Investigations, it became obvious  that
     1t would be difficult and  more costly to Implement Individual
     remedies at the two sites  because of their close proximity.
     U.S. EPA 1s selecting a combined remedy to clean up the sites,
     as explained 1n this document.

     The Envjro-Chem Corporation and Northside Sanitary Landfill
     (NSL) are located 1n a rural area of Boone County, about  five
     miles north of Z1onsv1lle  and ten miles northwest of Indianapolis
     (Figure 1).  Farmland borders the southern and eastern  edges of     *•
     the combined site area.  Residential properties are located  to  the  -t
     north and west, within one-half mile of the facilities.  A small     |"
     residential community, Northfield, 1s located north of  the sites
     on U.S. Route 421.  Approximately fifty residences are  located
     within a mile of the sites.              .

     An unnamed ditch runs north to south between the two sites,  along
     the western edge of the landfill, and joins Flnley Creek  at  the
     sffuthweTEern corner of the landfill (Figure 1).  Flnley Creek runs
     along the eastern and southern edge of the Northside site and flows
     Into Eagle Creek about one-half nrile downstream from the  sites.
     Eagle Creek flows south from Its confluence with Flnley Creek for
     ten miles before 1t empties Into Eagle Creek Reservoir.  The res-
     ervoir supplies approximately six percent of the drinking water
     for the City of Indianapolis.

II.  Site History - ECC

     ECC b«9ait operations 1n 1977 and was engaged 1n the recovery/rec-
   ' 1 amat1on/broker1ng of primary solvents, oils, and other wastes  .
     rectlvtd from Industrial clients.  Waste products were  received
     In drums and bulk tankers  and prepared for subsequent reclamation
     or disposal»

     Accumulation of contaminated stormwater onslte, poor management
     of the drum Inventory, and several spills caused State  and U.S.
     EPA Investigations of ECC.  In an attempt to handle wastes gener-
     ated onslte, approval was  sought by ECC to dispose of 5,000
     gallons per day of oil recovery wastes and 1,000 to 1,500 gallons
     per week of still bottoms  at NSL.  Approval to dispose  of the
     still bottoms was granted (with conditions) by the Indiana Stream
     Pollution Control Board (SPCB) on October 11, 1977; however, the
     request to dispose of the liquid waste from the oil recovery
     operations was denied.

-------
                            -2-
Subsequently, the company sought other avenues of waste disposal.
An  agreement was reached between the Indiana State Board of Health
(ISRH), ECC and NSL to allow disposal of oily wastes In the landfill
with municipal refuse.  Following expiration of this agreement
May 1979, ECC- added units to process wastewater by distillation
onslte.' The product water was used as boiler makeup water.

In  September 1979, the SPCB met to discuss an intentional  re-
lease of process and discharge water from ECC. The board ratified
an  Agreed Order that included a fine and provisions to upgrade the
methods of recordkeeping at the facility.

By  April 1980, the ISBH submitted documentation to the Indiana
Environmental Management Board (EMB) concerning ECC violations of
the Environmental Management Act, the A1r Pollution Control Law,
and the Stream Pollution Control Law.  Based on these violations,
the EMB referred the matter to the Office of the Attorney General
1n  May 1980.

On  November 19, 1980, a Resource Conservation and Recovery Act (RCRA).
Part A application was filed with U.S. EPA to operate a container
and tank storage facility.  On February 10, 1982, U.S. EPA          ?
requested that ECC submit a RCRA Part B permit application.  The    *"
application was due on August 18, 1982, but was not submitted.       \

A Consent Decree was Issued in July 1981, by the Boone County Circuit
Court, Imposing a civil penalty against ECC.  Furthermore, the court
placed ECC Into receivership and prohibited the company from using
NSL for disposal  of wastes.  The decree gave ECC until November 1982,
to comply with environmental laws and regulations.

In February 1982, the EMB placed a freeze on drum shipments to the
facility to assure compliance with the Consent Decree regarding
storage of drums, location of materials onslte and In transit,
and the removal  of sludge.

In May 1982, ECC  was ordered by the court to close and environmen-
tally secure the site for failure to reduce hazardous waste inven-
tories.  Two days later ECC's court receiver filed a closure plan
with th* Boon*-County Circuit Court.  By August 1982, ECC  was found
to to Insolvent.
    "•«:                                                           •
Surffcc* contaminants were removed from ECC In an operation extending
fro* March; 1983 through 1984.  Actions included removal and treatment
or disposal  of cooling pond waters, approximately 3U,UUO drums of waste,
220,000 gallons of hazardous waste from tanks, 5,650 cubic yards of
contaminated soil' and cooling pond sludge.

-------
                                 -3-
     In March 1985, contaminated  water was discovered ponded on the con-
     crete cap at the southern  end  of ECC.   It was determined that this
     wafer was runoff,  and  not  ground water  rising up through the
     concrete pad.  During  the  resulting  emergency action, a sump was
     constructed at the southeast corner  of  the  site, and 20,000
     gallons of contaminated water  containing high levels of volatile
     organics were removed  and  disposed of.

     The ECC site was included  on the proposed National Priorities List
     of December 1982,  and  was  made final in September 1983.  The
     site is currently  ranked 230 out of  a total of 951 sites.

III. Current Site Status -  ECC
     As a result of the emergency  action  in  1983, all drums onsite were
     removed, and all  tanks  were emptied  and cleaned.  The wastes
     and sludge in the cooling  pond  were  removed and disposed of, and the
     pond was filled in.   The only structures remaining on the site are
     the cleaned tanks, the  process  building, the A-frame structure and the
     concrete pad at the south  end of the site (Figure 2).  The emergency  •
     actions taken have eliminated the  major surface sources of contaminant^
     tion at the ECC site.  A current source of contaminant at the site  |"
     is the soil  which contains high concentrations, of organic compounds.I .
     It 1s possible that  other  sources  may be present within the area to _
     to be remediated.'

     A. Hazardous Compounds  Present  at  ECC

     The contamination found in certain media, such as soil, is obviously
     attributable to ECC.  However,  determining the source of contamination
     in the surface water  and sediments,  and the ground water is not as
     straight-forward, because  of  the location of the sites relative to each
     other.  The following presentations  for surface water and sediments,  and
     ground water discuss  and Identify  ECC as the potential source of the
     contamination, where  possible.

     1.  Soil

     Soil samples w»f« taken in two  phases - phase  I, which was done
     before th« removal of 2 feet  of contaminated surface soil from
     motfTof tn» site, and phase  II  which was done after the surface-
     reWNftt*  Th* results of the  phase II sampling show that contami-
     natedTsotls are present over  much  of the ECC site.  Volatile
     organic compounds are the  most  widespread organic contaminant at
     ECC and were detected to the  maximum soil sampling depth of 8.5
     feet.  The volatile organic compounds ranged up to 14,600,000
     ug/kg.  Other types of  contaminants  found in the Phase II sampling
     effort at ECC Include phthalates,  acid  extractable compounds, poly-
     nuclear aromatic  hydrocarbons,  and polychlorinated biphenyls (PCBs).

-------
                             -4-
 2.   Surface Water and Sediments

 The City of Indianapolis  has detected organic compounds in Finley
 Creek .ajt Highway 421  (Figure 1) since 1984.  In addition, during
 the Remedial  Investigation  (RI) organic contamination, consisting
 mainly  of  chlorinated hydrocarbons, was found at one off-site
 sample  location.  This sample location is in Finley Creek
 downstream of both ECC and  NSL.  It is therefore difficult to pin-
 point the  exact source of the chlorinated hydrocarbons.  However,
 a review of ECC site records and the chemical analysis of environ-
 mental  media  at ECC has shown that the types of compounds and their
 relative ratios are consistent with those compounds identified at
 the downstream sampling location.

 ECC  site records report that chlorinated hydrocarbon solvents were
 processed  at  the facility.  Further, drainage patterns direct over-
 land flow  from the vicinity of the ECC and NSL sites toward the
 downstream sampling location.  A second sampling location is approxi-
 mately  750 feet upstream  of the downstream location on Finley Creek  .
 but  receives  runoff only  from the NSL site.  Surface water from this
 sampling location was not found to be contaminated by chlorinated   |
 hydrocarbons.                                                       4"

 Ponded  water  was discovered on ECC and was sampled after the        _
 surface cleanup was completed.  Results of these analyses reveal
 that all three sample locations were contaminated with a variety
 of  base/neutral and volatile organic compounds.  Several of
 the  volatiles were also detected at the downstream location.

 J~.   Ground Water

 The  Remedial  Investigation  (RI) identified two hydrogeologic units
 beneath ECC.  From the surface, these units are:  a zone of glacial
 till with  sand and gravel lenses (also referred to as glacial till
 water-bearing unit); and a  deep confined aquifer consisting of sand
 and  gravel.   A large sand and gravel lens was encountered in the
 glacial till  water-bearing  unit beneath ECC.  In the ECC RI, this
 unit was referred to as the shallow sand and gravel zone.  This
 sand and gravel zone extends Into the southwest corner of NSL.

Ground  water  below ECC generally travels south and discharges Into
F1n4ey Creek  or the unnamed ditch near the confluence with Finley
Creekv  Interpretation of hydrogeologic data Indicate that Finley
Creek Is a ground water discharge area.

 In the  shallow saturated zone, which consists of glacial till
 above a large sand and gravel lens, the following 11st of contami-
 nants were found at the Indicated levels In two shallow wells (15
 feet and 24 feet deep) near the southern end of ECC:

-------
                            -5-
    trans-l,2-dichloroethene          4,000 ug/1
    trlchloroethene                  28,000 ug/1
    benzene                     less than 9 ug/1
    1,1-dichloroethane                   96 ug/1
    chloroform                  less than 9 ug/1
    I,fr-d1chloroethene                   10 ug/1
    trans.-l,3-d1chloropropene            77 ug/1
    vinyl chloride                       86 ug/1

The underlying sand and gravel lens was also found to be contamina-
ted with Inorganic and organic compounds.

Contamination was not found in the deep confined aquifer.

B.  Pathways of Exposure at ECC for the No Action Alternative

1.  Soil

Following the 1983-1984 emergency action, a 1-foot glacial  till
cover was placed over the northern portion of ECC.  This material
was taken from a borrow area north of NSL, was tested and found
to be clean before placement.  Samples taken thereafter of  ponded
water on the cover material, as well as the surface water runoff
from this area, reveal contamination of the cover material.

The cover material could have been contaminated in a number of ways."-"
The physical placement of the cover and the use of heavy equipment
to put It In place during wet weather may have caused the cover mate-
rial to be mixed with the contaminated soil below.  In addition, up-
ward migration of contaminants Into the cover material, as  a result of
Capillarity, could have occurred.

A fence around ECC currently limits unauthorized access and  direct
contact with the contaminants onsite.

Transport of contaminants from onsite soils 1s also likely  through
leaching.  As water Infiltrates through the contaminated soil, it
will desorb many compounds and eventually leach Into the ground
water In the shallow saturated zone.  This 1s presently the  case
as tht, ground witer samples from the shallow saturated zone were
      to be> contaminated with volatile organlcs.
2* ISttrfice Water and Sediments
    -••i
      .«.•
Roth tto unnamed ditch and Finley Creek receive ground water dis-
charge and surface water runoff from ECC.  Contaminants in the sur-
face water may volatilize, degrade precipitate or adsorb to sediments,
or remain In solution and be transported downstream to Eagle Creek
and eventually the Eagle Creek Reservoir.  Contaminants within the
stream sediment may dissociate and reenter solution or may be
scoured and resuspended in high flow and carried downstream.

-------
                            -6-

3.  Ground Water

Contamirfants have migrated downwards to the shallow sand and
gravel aquifer.  This is evidenced by low-level contamination
found in the shallow sand and gravel aquifer onsite.  Vertical
gradients between the shallow saturated zone and the sand and
gravel aquifer currently are upward.  However, future excavation
at the site could exa seer bate ponding of water onsite and reverse
the gradient, enabling downward migration of contaminants to
the shallow sand and gravel aquifer.  In addition, pumping wells
placed in the sand and gravel aquifer could reverse the vertical
gradient.  Some contamination may remain in the cooling pond
and may also cause continued contamination of the shallow
sand and gravel aquifer.

Evidence of downward migration of contaminants from the shallow
sand and gravel and glacial till to the deep confined aquifer
was not found and is highly unlikely now or 1n the future
due to.the upward vertical gradient.

C.   Risk to Receptors at ECC for the No Action Alternative

1.  Soil

Because the surface of the ECC site 1s contaminated, receptors
(plants and wildlife, as well as humans) could Inhale, Ingest,
and contact hazardous compounds in the soil directly.

In addition, the heavily contaminated soil below the cap could
be a risk to receptor populations since any future excavation
might ffrfng higher concentrations of contaminants to the surface.

2.  Surface Water and Sediments

Receptors may be exposed to contamination 1n surface water by
wading in the creek, Ingesting contaminated water, or Ingesting
fish which have bloaccumulated contaminants.  During low flow
periods, contaminated sediments may be exposed along the stream
banks and may adhere to hands, clothing or pets and be transpor-
ted Into the HOM 1n this manner or as dust, and Inadvertently
Ingested or Inhaled.

3* - Ground Water

During the RI, five residential wells within one-half mile of
ECC were sampled and analyzed for Inorganics and organlcs.  No
evidence was found that contamination from ECC has migrated to
the residential wells.  However, receptors could potentially
contact or Ingest the contaminated ground water if potable wells
were to be constructed within the zones of contamination.

-------
                                -7-
IV.  Site History - NSL

     Front aerial  photos,  it  appears  that  landfill operations began some-
     time between- 1955 and  1962.  From  1972 to  1973, numerous operational
     deficiencies were  reported to  ISBH inspectors  including failure to
     cover refuse, surface  burning,  underground fires, leachate and vermin
     problems.   In June  1972 and  December 1973, ISBH ordered the owner to
     cease operations at  the landfill.  The operation continued into early
     1974, which  resulted 1n the  State  issuing a complaint in May 1974
     again ordering operations to cease.   In February 1975, a permit was
     issued to  operate the  landfill.

     In March and September  1978, ISBH  noted that unapproved wastes were
     disposed of  at NSL  including paint sludges, acids, spent acids and
     waste oil.

     Between 1979 and 1982,  portions  of the unnamed ditch and Finley Creek
     were rechanneled by  the owner  of NSL.  Some of these former drainage-
     ways were  not filled in and  are currently evident.

     In April 1980, U.S.  EPA Inspectors reported that leachate from NSL  |
     was observed entering the unnamed  ditch on the west side of the sltejf"
     The owner  of NSL was ordered to  remedy the problem which he attempt ail .
     to do by applying clay  to the  affected area.

     In November  1980, the  owner  filed  a  RCRA Part A application to operate
     NSL as an  existing  hazardous waste disposal facility.  In February
     1981, the  owner requested zoning approval  from the Boone County Area
     Planning. Commission to  expand  the  landfill east of the existing land-
     fill  area.  By 1981, NSL had accepted at least 16 mi VI ion gallons of
     hazardous  substances.

     An Agreed  Order was  signed in  July 1981 between the Environmental Manage-
     ment Board (EMB) and NSL whereby NSL was ordered not to accept waste
     from ECC.  This order  arose  partly from reports that NSL accepted un-
     approved waste from ECC.

     In October 1981, NSL was given conditional approval to receive
     sewagt sTudgvfbr disposal,  provided that the owner first Install a
 .,  leacfrat* collection system.  NSL was Issued a  Notice of Violation in
     Jud* 1982, for accepting sludge  prior to the completion of the •
             system*
     In March  1982,  the owner applied  to  ISBH  for a  permit  to  operate  NSL
     as a  hazardous  waste  landfill.  The  State refused  this  application
     1n July 1982, after ground water  contamination  was observed  in  a

-------
                               -8-

   monltoring well located near the southwest corner of the landfill,
   adjacent to the unnamed ditch.  In addition, ISBH required the owner
   to  begin the assessment stage of a RCRA ground water monitoring program.

   In  September 1983, NSL submitted a RCRA Part B permit application to
   U.S. EPAi.-An Inspection of the landfill by State inspectors in
   December 1983, found that leachate seeps were continuing on the north
   and east sides of the landfill and that the leachate collection tanks
   were in need of pumping.  In November 1985, U.S. EPA denied the RCRA
   Part B application for NSL.

   In April 1983, NSL's Hazardous Waste Operating Permit was denied be-
   cause of deficiencies in its closure, post-closure and ground water
   assessment plans.  In October 1983, NSL's Solid Waste Operators Permit
   was denied because of leachate collection problems and acceptance of
   unapproved waste.

   In May 1983, the EMB issued a Notice of Violations, Compliance Order and
   Hearing to NSL, alleging numerous violations of the Indiana Environmental
   Management Act and associated rules, and ordered NSL to undertake certain
   remedial measures.  The State was joined 1n this action by several  res-
   idents living within 1.5 miles of NSL in September 1983.  The hearloo
   began in January 1984, and the hearing officer released his Kecommeaped
   Final Order in November 1986.  In February 1987, the Indiana Solid Ifiste
   Management Board (assuming the responsibility of the EMB) adopted trae.
   hearing officer's recommended final order.  Among the stipulations  of.
   this order are:

     -  NSL shall install and maintain a functioning leachate
        collection system at the base of the trash around the
        entjre perimeter of the landfill;

     -  NSL shall Install a slurry wall (hydraulic cut-off
        barrier), or undertake construction utilizing a
        different technology, with the objective being to pre-
        vent contaminated ground water from migrating off-site;

     -  NSL shall conduct ground water monitoring pursuant to
        RCRA monitoring protocol;

     •  NSL shall*accept no further solid waste except that
,    'amount needed to adequately contour the site.
     •A* '                               •
   TttiMlSb'site was Included on the proposed National Priorities
   List of September 1983, and was made final In September 1984.
   The site Is currently ranked 237 out of a total of 951 sites.

V. Current Site Status - NSL

   As of April 1987, NSL was continuing to operate as a solid waste
   landfill.  The RI revealed contamination In the subsurface soil,
   surface water and sediment, leachate, and ground water.

-------
                                 -9-
A.   Hazardous Substances Present  at NSL

     The contamination found in certain media,  such  as  soil  and leachate,
     1s obviously attributable to  NSL.  However, determining the source
     of contamination 1n the surface water and  sediments, and ground
     water 1s not as straightforward, because of the location of the sites
     relative to each other.  The  following presentations for surface
     water and sediments, and ground water discuss and  Identify NSL as
     the potential source of contamination, where possible.

     1.  Soil

     Surface soil samples were taken from the landfill  proper and  showed
     no contamination.  It 1s believed that these samples were taken
     from uncontamlnated cover material that was part of the sanitary
     landfill operation.  However, all of the subsurface soil samples,
     taken from all  sides of the landfill, showed contamination.   The
     highest contaminant concentrations were found near the  southwest     ^
     corner of the landfill  (Figure 3).   The contaminants found 1n sub-   %.'
     surface soil samples Include  volatile organlcs, oil and grease*      i
     Inorganics, and pesticides.                 .                       f

     2.  Surface Water and Sediments

     Surface water sampling was conducted 1n two phases.  The highest
     concentration of contaminants 1n the surface water was  found  1n
     the unnamed ditch between ECC and NSL, and 1n Flnley Creek down-
     stream UT ECC and NSL (Figure 3).  Contaminants found Include
     Inorganics, volatile organlcs, and base neutrals and adds.

     Analysis of sediment samples  revealed a wide variety of organic
     contaminants.  The greatest number and the highest concentration
     of contaminants were detected 1n Flnley Creek below the confluence
     with unnamed ditch (Figure 3).  Inorganic  contamination was also
     found 1n Flnley Creek upstream of the confluence with unnamed ditch.
     In the sediments of Flnley Creek below the confluence with unnamed
     ditch, and also In a former segment  of Flnley Creek near the  south-
     east corner of NSL, PCBs were detected. Pesticides were also detec-
     ted, In Flnley Creek sediments near the southeast corner of NSL. .

     3.  Leachate

     Leachate was sampled and analyzed from a variety of sources on  all
     sides of the landfill.   These samples Included  leachate liquid  from
     the landfill, other liquids observed 1n ditches Immediately adjacent
     to the landfill, soil at leachate sampling points  and 1n ditches, and
     the leachate collection tanks.  The  leachate soils had  more compounds

-------
                            -10-
and concentrations of contaminants than the liquid.  The RI found
that the  leachate soil samples collected on all sides of the
landfill  showed contamination.  Contaminants found in these
so1ls-4ncfude organic and inorganic compounds.

Sampling  and analysis of the existing leachate collection tanks
revealed  a variety of volatile organics, base neutrals and acids,
and inorganics.

4.  Ground Water

The hydrogeologic units beneath NSL are essentially the same as below
ECC.  From the surface these units are:  a zone of glacial till with
sand and  gravel lenses (also referred to as glacial till water-beariny
unit); and a deep confined aquifer consisting of sand and gravel.  A
large sand and gravel lens was encountered in the glacial till water-
bearing unit beneath ECC.  In the ECC RI, this unit was referred to
as the* shallow sand and gravel zone.  This sand and gravel zone
extends Into the southwest corner of NSL.

In the glacial till, contamination was found in the ground water on$
all sides of the landfill.  Analysis of the ground water in the glaffal
till zone revealed a wide variety of inorganics, semi-volatlies and!
volatile organics, such as trichloroethene.

Water samples obtained from the sand and gravel lens in the southwest
corner of NSL contain sem1-vo1at1les, pesticides, inorganics, and volati.
organics  Including two at concentrations higher than U.S. EPA
max1mum_contaiTrinant limits.  These chemicals are benzene and 1,1-

-------
                                 -11-
     eventually to Eagle Creek Reservoir.

     Contaminants within the stream sediment may dissociate and reenter
     solution or-may be scoured and resuspended in high flow and carried
     downstream.

     3.  Leachate

     Leaching represents a significant transport of contaminants.  As  water
     infiltrates through the contaminated soil and debris, it will  desorb
     many compounds and eventually leach into the ground water within  the
     glacial till water-bearing unit.  This is presently the case as the
     ground water samples from the glacial till water-bearing unit were
     found to be contaminated with Inorganics and organlcs.  Leachate  also
     seeps from the side slopes of the landfill and discharges to the
     unnamed ditch and Finley Creek.

     4.  Ground Water

     Contaminants In the glacial till water-bearing unit migrating downwards
     contaminate the sand and gravel lenses.  Low-level contamination  foihd
     in the sand and gravel lenses indicate that this has occurred.
,1
     Evidence of downward migration of contaminants from the glacial  til,
     water-bearing unit to the deep confined aquifer was not found in the ECC
     RI and Is highly unlikely now or in the future due to the upward vertical
     gradient reported therein.

     the hy4cogeological investigation conducted during the RI indicated
     that contamination from the glacial till water-bearing unit and  the
     shallow sand and gravel lenses within that unit migrate to the unnamed
     ditch and/or Finley Creek.

C.   Risk to Receptors at NSL for the No Action Alternative

     1.  Soil

     Heavily contaminated subsurface soil could be a risk to receptor popula-
     tions since*erosion or future excavation might bring contaminants to the
  f  surface*  One* chemicals are at the surface, receptors (plants,  wild-
     Hftvand aquatic organisms as well as humans) may inhale, ingest, and
     contact harmful compounds directly.

     2.  Surface Water and Sediments

     Receptors may be exposed to contamination in surface water by wading in
     the creek, Ingesting contaminated water, or ingestion of fish which have
     bioaccumulated contaminants.

     During the low flow periods, contaminated sediments may be exposed along
     the stream banks and may adhere to hands, clothing or pets and be trans-
     ported into the home*in this manner or as dust, and inadvertently
     Ingested or Inhaled.

-------
                                 -12-
     3.  Leachate.

     The greatest risk presented by leachate 1s after 1t enters another
     med1 um.

     Once 1n the ground water, leachate will have the same risk to re-
     ceptors as the ground water Itself; that 1s, receptors could  poten-
     tially contact or Ingest the contaminated ground water 1f potable
     wells were to be constructed within the zones of contamination.

     In the surface water, leachate will pose a risk to receptors  who
     may be exposed by wading 1n the creek, Ingesting contaminated water,
     or Ingesting fish which have bloaccumulated contaminants.  Further,
     the leachate may be toxic to fish themselves.

     4.  Ground Water

     During the RI, five residential wells within one-half mile of NSL
     were sampled and analyzed for Inorganics and organlcs.  No evi-
     dence was found that contamination from NSL has migrated to the
     residential wells.  However, receptors could potentially contact
     or Ingest the contaminated ground water 1f potable wells were to
     be constructed within or Immediately adjacent to the zones of
     contamination.

VI.  Combined Action Alternatives Evaluation

     Because the ECC and NSL sites are next to each other, 1t became
     obvious during the Remedial Investigation for each site that
     1t would be difficult and more costly to Implement remedies for
     the two sites Individually.  For this reason, 1t was decided
     that a separate report, based on the Feasibility Studies, be
     prepared to discuss a combined remedy for the two sites.  This
     final  report was called the "Combined Alternatives Analysis
     Report, Northslde Sanitary Landfill and Environmental Conservation
     and Chemical Corporation" (CAA).  The alternatives developed  1n
                 derived from the alternatives developed for the
                sltts and discussed 1n the ECC and NSL Feasibility   .
     Stupe***  The purpose of combined alternatives for the adjacent
     sltthrts to ensure that the remedial actions are compatible with
     eaclr other, to avoid duplicate remedial actions, and to Integrate
     remedial actions to achieve cost savings.

     A.  Remedial Action Goals

     Remedial action goals were developed and presented 1n the ECC
     and NSL FS reports to address each of the site hazards Identified
     for the sites.  They were Identified for each of the following
     operable units:  soil and landfill contents, landfill leachate,
     ground water, and surface water and sediment.

-------
                        -13-
1.  Remedial Goals for Soil and Landfill  Contents

Minimize Direct Contact—Minimize risk to public health
and environment from direct contact, inhalation or ingest ion
of"NSL landfill contents, contaminated surface or subsurface
soil on ECC and NSL, leachate soils and sediment in the old
creek beds of Finley Creek.

2.  Remedial Goals for Leachate

Minimize Direct Contact--Minimi2e risk to public health
and environment from direct contact with  NSL leachate
liquid in the collection system and leachate seeping from
the sides of the landfill.

Control Migration to Ground Water—Minimize and mitigate
leaching of contaminants from the ECC-contaminated soil
or. NSL contents into the ground water to  adequately
protect potential  receptors of the ground water at or
near the site.
                                                               f
Control Migration to Surface Water—Minimize and mitigate      |fc
the overland migration of contaminants from leachate seeps     f
to the unnamed ditch and Finley Creek to  adequately protect     /
public health and the environment from surface water and
sediment contamination, ingestion of contaminated aquatic
life, and direct contact with leachate liquid.

3.	Remedial Goals for Ground Water

Minimize Direct Contaminant Consumption—Minimize current
and possible future risk to public health from direct con-
sumption of contaminated ground water by nearby users.

Control Migration to Surface Water—Manage migration of
contaminated ground water to the unnamed  ditch and Finley
Creek so public health and the environment are adequately
protected from surface water and sediment contamination
and Ingosttofl of contaminated aquatic life.

4.  Remedial Goals for Surface Water and  Sediment

Control Migration to Surface Water—Minimize and mitigate
the threat to the environment and public  health from direct
contact, Inhalation, and Ingestion of contaminants in
surface water and sediment resulting from future release
of hazardous substances from landfill leachate and ground
water discharge.

-------
                            -14-
 B.  Combined Alternatives Considered

 The nine  combined  remedies developed and presented In the CAA
 are derived from the alternatives developed for the NSL and ECC
 sl-tes  and presented in detail in the respective FSs.  Since each
 of  the.NSU. or ECC  alternatives contains many individual compon-
 ents,'the possible combinations far exceed the nine CAA alterna-
 tives  developed.   The CAA alternatives are intended to represent
 a wide range, both in terms of cost and public health and environ-
 mental  benefits, of alternatives that meet the remedial action
 goals.

 Alternative 1—No  Action

 The No Action Alternative 1s required by the National Contingency
 Plan and the National Environmental Policy Act to be carried
 forward.  It provides a baseline for comparison of other alter-
 natives.

 Alternative 2—Access Restrictions with Soil Cover and Leachate
 Collection and Treatment

 Alternative 2 Includes deed restrictions, fencing, a soil cover
 over the landfill  to promote revegetation, a soil cover over
 the ECC site, disposal of sediment on NSL, rerouting the surface
 waters, collection and treatment of the leachate seeps, and
 monitoring of the  leachate, ground water, and surface water.
 This alternative addresses all  of the operable unit goals with
 two exceptions.  It would not mitigate or minimize the leaching
 of  contaminants from ECC or NSL to the ground water nor would
 it  manage the migration of contaminated ground water to the sur-
 face waTers.

 The Intent was to present a low-cost alternative that offers the
 lowest  level of protection to public health and the environment.
 If  contaminant concentrations in the proposed monitoring wells
 exceed applicable and relevant and appropriate requirements (ARARs)
 limits, future remedial  actions would be Initiated.  Alternative
 2 Is estimated to cost $18.1 million.

Alternative 3—Access Restrictions With RCRA Cap and Leachate
Collection and Treatment

Alternative 3 1s Identical to Alternative 2 with the exception
 of a RCRA cap over both  sites in place of a soil cover.  This al-
ternative 1s Intended to provide a greater level of protection
 by  reducing contaminant migration to the ground water through
 reduction In surface water Infiltration while also meeting tech-
 nical  requirements of landfill  capping for site closure under
RCRA.   Monitoring would still be necessary to detect migration
 of contaminants 1n the ground water.  The quantity of leachate
migrating to the ground  water will be reduced; however, the

-------
                            -15-

 contlnulng contamination of the surface water from ground water
 discharge remains.  As with Alternative 2, If contaminant con-
 centrations 1n the proposed monitoring wells exceed ARARs,
 future remedial actions would be initiated.  Alternative 3 is
 estimated to cost $29.9 million.

 Alternative'4—Access Restrictions With Soil Cover. Leachate
 Collection, Ground Water Interception, and Treatment

 Alternative 4 is essentially identical to Alternative 2 with the
 addition of ground water interception and treatment to mitigate
 the migration of ground water contaminants offsite or to the
 surface waters.  This alternative addresses the ground water and
 surface water remedial action goals of providing adequate protec-
 tion of public health and the environment from further contamina-
 tion of the surface water.  Leachate from NSL would continue to
 migrate to the ground water so collection and treatment would be
 required .Indefinitely at NSL.  At ECC, soil contaminants which
 leach to ground water would be removed and treated, though treat-
 ment would also likely be required indefinitely (possibly for 1UU
 years or more).  Alternative 4 1s estimated to cost $20.8 million.

 Alternative 5—Access Restrictions with RCRA Cap, Leachate
 Collection, Ground Water Interception, and Treatment

 Alternative 5 Includes leachate and ground water interception and
 treatment with a RCRA cap over the sites.  The objective of the
 cap Is to minimize further leaching of soil or landfill contaminants
 to the ground water.  This may eventually allow termination of the
 ground water collection and treatment system, though leachate collec-
 tion and treatment would continue to be necessary.  The operational
jaerfod-of the collection and treatment system cannot.be reliably
 estimated but could be less than the time required for Alternative 4,
 Alternative 5 1s estimated to cost $33.9 million.

 Alternative 6—Access Restrictions With RCRA Cap, Leachate
Collection. Ground Water Isolation and Treatment

 Alternative 6 employs a ground water collection system Intended
 to lower the water table beneath the contaminated or potentially
 contaminated zones at both sites.  Combined with a RCRA cap the
 alternative should eventually prevent further contamination of
 thikground water and result in treatment of leachate only.
 HoMiMtr* the collection system would be operated indefinitely
 tornftintaln the lower water table.  This alternative 1s Intended
 taprovide a greater level of protection to the public health
 and environment by reducing contaminant migration.  Alternative 6
 Is estimated to.cost $37.3 million.

 Alternative 7—Access Restrictions With RCRA Cap. Leachate
Collection. Ground Water Isolation and Treatment, and ECC
 Soil Vapor Extraction

Alternative 7 Incorporates all the components and objectives of

-------
                        -16-
Alternative 6 with the additional  treatment of ECC-contaminated  soil.
Because the alternative Includes a RCRA cap over ECC  combined  with
a lowering of the water table, the soil  vapor extraction treatment
would not likely result in a reduced ground water treatment  period
relative-to Alternative 6.  This 1s because In either alternative
leaching of soil contaminants to the ground water 1s  minimized by the
cap and the lowering of the water table.  The public  health  risk
from direct contact with ECC-contaminated soil  in the event  of site
development would be greatly reduced.  Alternative 7  Is estimated
to cost $39.3 million.

Alternative 8—Access Restrictions With RCRA Cap, Leach ate
Collection, Ground Water Isolation and Treatment, and ECC
Soil Incineration

Alternative 8 Incorporates the objectives of Alternative 7.
ECC-contaminated soil, however, 1s treated by onslte  Incineration.
This results In permanent destruction of the organic  contaminants.
Alternative 8 1s estimated to cost $76.1 million.

Alternative 9—Access Restrictions M1th Onslte RCRA Landfill

Alternative 9 Includes deed restrictions, excavation  of the  land-
fill contents, peripheral soils, sediments and ECC-contaminated
soil and disposal of the waste materials 1n an onslte RCRA-type
facility.  This alternative addresses all the operable unit  goals
and provides the highest level of protection of all the alternatives.
However, the risks of exposure during construction and Implementation
would be greater than any of the other alternatives.   Alternative
9 1& estimated to cost $109.4 million.

Alternative Combinations Not Included

Several  potential combinations of NSL and ECC alternatives were
not Included since they either did not satisfy the remedial  action
goals, or other combinations better satisfied the objectives
Intended.. They are discussed below.

- ECC Soil Excavation and Disposal Offsite

, Thts action was not Included In any CAA Alternative since  it is .
  costly-(3
-------
                                 -17-
     Mglr cost (capital  cost  1s  estimated  to  be  $3  billion to $5
     billion).  Incineration  of  isolated and  heavily  contaminated
     areas within the landfill could  be accomplished  at  a much  lower
     cost If" such areas  could be effectively  located. Risks of ex-
     posure or offslte migration of contaminants during  excavation
     would.-stUl  be important disadvantages.

VII. Recommended  Alternative

     U.S. EPA's recommended alternative is Alternative 5 (Figure 4).
     The major components  of  the alternative  are:   access restrictions;
     RCRA-compliant cap  and surface controls;  monitoring; leachate
     collection,  ground  water interception; and  treatment.

     •  Access Restrictions

        Deed restrictions  will be placed on the  landfill property and
        the ECC site. The restrictions should prevent future develop-
        ment of the land to protect against direct  contact with con-
        taminants or further  migration  that could result from site
        excavation and development.  The deed restrictions should also
        prohibit  use of  ground water  or Installation  of  wells onsite.   4-
        Access to the site will  be controlled by completing the fencing |
        around the site  perimeter and posting signs.                    $"
                                                                        £
     •  RCRA-CompHant Cap and Surface  Controls

        These actions Include removal of contaminated sediment, rerouting
        of creeks, and construction of  a multi-layer  cap over ECC and NSL.
        The cap will be  designed to comply with  RCRA  performance-based
        standards.  In addition, the  needs for an appropriate gas venting
        system will be determined during design.

        Contaminated leachate soils and sediment in the  ditch north of
        NSL and the old  creek beds of Finley  Creek  would be excavated,
        dewatered, and disposed  of onsite  beneath the cap.  It  was assumed
        for cost  estimating that excavation to a 1-foot  depth would be
        necessary and a  total of 4,200  cubic  yards  would be removed.

        Th* actual volume  removed will  be  dependent on further  sampling
                   a* part of final design.  The creek beds will be
                   and a soil cover would  be  placed over areas  not under
            cap**  Contaminated water  resulting from, the  dewatering of
            sediment will  be  treated  in the onsite  treatment system.
        The unnamed^ ditch will  be rerouted to the west  of ECC  and portions
        of F1nley Creek  will  be rechannellzed as shown  in Figure 4.   This
        will  route surface waters farther away from contaminated areas,
        and Increase the space available to construct the French drain system.

        Prior to placing the  cap, the site will  be graded to eliminate sharp
        grade changes and to  provide for drainage.  Also the former process
        building on the  ECC site will be demolished. The concrete floor and
        foundation will  remain and the cap placed on top.  The cap will  be
        seeded to control  erosion and promote evapotranspl ration.

-------
                         -18-
Mkm1tor1ng

Contami n'ant migration and remedial action performance will  be
assessed through a regular leachate, ground water, and surface
water monitoring program.  Leachate will be sampled at the
leachate collection sump as part of the leachate collection
and treatment system.  Ground water will be monitored during
the first year using 15 of the existing wells and an additional
26 new monitoring wells (Figure 4).  The 41 monitoring wells
will be sampled quarterly the first year and analyzed for the full
organic and Inorganic priority pollutant list.

Sampling needs may change over time as different types and concen-
trations of contaminants migrate to the monitoring points.   It 1s es-
timated that subsequent semiannual sampling will be necessary at
14 wells.  Water levels of monitoring wells will be taken at the
time of sampling and gradients will be calculated.

Surface water and sediment will be sampled at eight locations semlr
annually.  These samples will be analyzed for volatile organic   iw
compounds, base/neutrals, pesticides, PCBs, and Inorganics.      I
Depending on surface water results, fish may be occasionally     s
collected from Flnley and Eagle Creeks and their tissues analyzed-
for bloaccumulatlon of organic contaminants.

Leachate Collection

The leachate collection system will consist of a French drain en-
circling the landfill.  The drain will be about 4 feet deep and
about 6,000 feet 1n length.  Perforated pipe laid In the trench
will be used to transport leachate to a sump located near the
treatment system 1n the southwest corner of the site.

The trench will be backfilled with gravel.  A 1-foot layer
of gravel will also be placed on the sldeslopes of the landfill
to provide a drainage path for leachate seepage.  The multl-
laytr cap, will extend over the gravel layer and the drainage
trench.  The existing leachate collection system will be evalu-
ated to determine Its effectiveness.  It will be decommissioned
and replaced, 1f necessary.

Ground Mater Interception

The objective of the ground water collection system 1s to
prevent contaminated ground water from migrating offsite
and discharging to surface waters.  The collection system
described for the recommended alternative will meet this
objective based on the Information available to date.  Further
site Investigations during final design may alter the design
and alignment of the collection system; however, the objective
of the ground water Interception system will be met.

-------
                            -19-
    The ground water collection  system will consist of a French
    drafn  installed  along the southern and southwestern boundaries
  •  of the landfill  and  ECC.  The trench will be about an average
    depth .of 25  feet  and will include two collection pipes, one
    set 5  feet below the existing water table and the other set
    at the bottom  of the trench.  It is anticipated that an ap-
    proximate 5-foot  overall drawdown of the water table at the
   .collection system will be sufficient to prevent ground water
    movement past  the system.  The French drain will include an
    impermeable  barrier  on the south wall of the trench to minimize
    inflow of water  from Finley Creek.  The barrier consists of an
    impermeable  synthetic membrane and at least 6 inches of com-
    pacted clay.   It will extend 3 feet into the till below the
    sand and gravel  deposit in the southwest area of the site.
    The barrier will  also extend 75 feet beyond the western end of
    the drain.

    The initial  combined flowrate from the leachate and ground
    water  collection  systems is estimated to be 100 gpm with
    40 gpm from the  leachate collection system.  Within 5 years,
    the flow is estimated to decrease to about 65 gpm because of
    a  reduction  in leachate generation from infiltration due to
    the Impermeable  cap.

 •   Treatment

    Treatment of leachate and ground water will be required to
    meet effluent  discharge limits and conditions to be set in
    an NPOES permit  for  discharges to Finley Creek.  The limits
~   Ulcely applicable are presented In Table 1.  The limits must
    protect  aquatic  life and human health from consumption of
    aquatic  organisms and human health from use of the downstream
    Eagle  Creek Reservoir as a drinking water supply.

    The onslte treatment system will be capable of meeting the
    effluent limits.  A  powdered activated carbon treatment (PACT)
    system has been  assumed as the system for leachate and ground
    water  treatment  because It Is a system suited to the kinds of
    character!sties  expected In the leachate and ground water.
    HtMver, the PACT system is  not the only system that could
    bemused for  treating the combined ground water/1eachate
  £.floMw~ Other treatment systems can be used, such as activated
   'sTudgrar biological contactors followed by activated carbon
    adsorption.  Implementation  of other treatment systems may
    result In different  costs.  The actual treatment system
    configuration  will be developed through pilot or bench testing
    during design  of  the final remedial alternative.  During
    final  design,  the treatment  system will likely be modified
    based  on pilot and bench-scale testing and more detailed
    evaluations of capital and operation and maintenance costs.
    The objective  of  meeting the discharge limits will be attained,
    however.

-------
                                  -20-
         Leachate and ground water will  be pumped  to  an  onslte  treat-
         ment plant consisting  of precipitation, biological oxidation,
         and carbon adsorption.   The two streams may  be  combined
         depending on the results of bench scale and  pilot  studies, In
         a 100,OOU-gal1on holding tank.   In the treatment system, the
         waste.stream first  passes through the precipitation process
         for removal  of metals  and other inorganics.  Chromium, copper,
         Iron, lead,  and zinc were detected in the ground water and
         leachate samples and can be removed by precipitation.  Hydro-
         xide precipitation  is  used for  cost estimating  purposes.  Floc-
         culation and clarification follow the chemical  addition and
         can be accomplished in  one basin.  Either flocculation with
         lamella gravity settlers or solids contact clarifiers  could
         be used.  Sludge is removed from the bottom  of  the basin and
         can be thickened, dewatered with a filter press, and disposed
         of 1n a RCRA landfill,  if required.

         Effluent from the precipitation process then goes  through the
         PACT system, which  1s a patented activated carbon  enhanced
         biological  treatment system. The PACT system combines biological
         treatment and carbon adsorption into one  process.  The system
         works through the addition of powdered activated carbon to the
         influent of  the activated sludge process.  The  system consists
         of carbon feeding equipment, an aeration  basin  with the necessai
         appurtenances, a clarlfler, and sol Ids handling equipment.  Sol'
         would be wasted to  an  aerobic digester followed by dewatering.
         Solids would then be disposed of at a RCRA landfill unless they-"
         could be delisted as a  nonhazardous waste.  Spent  carbon in the
         waste solids could  be separated and regenerated offsite.

    __   Grjmular media filtration would be Included  in  the treatment
         system following either the precipitation  system or the PACT
         system or both.   The advantage  of having  a filter  after each
         unit would be that  less metals  would carry over into the PACT
         system and that solids  with low settleability would be removed
         from the biological system effluent. For costing  purposes,
         however, It  Is assumed  that one filter will  be  used after the
         PACT system.

      *   Other Considerations

  f    i During rectnt Investigations, an additional  area of contamination
       :: was. discovered to the south and southwest  of ECC.  The suite of
     . * compounds found In  this area are similar  to  those  found at the ECC
         &1t*v  This  area (shown 1n Figure 4} will  be more  fully defined
         during the pre-design,  and will  be remediated along with ECC and
         NSL.  The ground water  collection system  may need  to be realigned
         to capture this contamination.

•VII.     Compliance with Superfund Amendments and  Reauthorlzation Act (SARA)
         Cleanup Standards

-------
                                 -21-

A. Compliance with SARA §121

1) General Guidelines

Section 121 -of SARA dictates cleanup goals and standards for remedial  action.
These begin with general guidelines for the selection of a remedy.  Remedial
actions whlcbjnclude treatment which permanently and significantly reduce
the volumeV tbxicity or mobility of hazardous substances, pollutants and
contaminants are preferable to those which do not.  Offsite transport and
disposal of contaminated material without treatment should be the least fa-
vored alternative where practicable treatment technologies are available.

Treatment of contaminated soil and refuse in order to permanently and
significantly reduce the volume, toxidty or mobility of contaminants at
ECC/NSL 1s not practicable.  Treatment of NSL refuse would be nearly
Impossible because of the variety of materials, large volume, and resulting
high cost.  Treatment of ECC soils alone would not significantly reduce
the amount of contamination at the combined site.  Off site transport of
contaminated material 1s not a part of the remedy.

The remedial action must be protective of human health and the enviro-
ment.  Sections III and V of this document summarize the present exposure
pathways and risks to human health and the environment.  This remedial
action will block those exposure pathways and protect human health, welfare,
and environment from toxic materials at the sites.                     |fc

The remedy must be cost effective.  Section 300.68(1) of the fCP states*
the appropriate extent of remedy 1s defined as a "cost effective remedial-
alternative that effectively mitigates and minimizes threats to and provides
adequate protection of public health and welfare and the environment."  The
FSs for ECC and NSL and the CAA carried out this analysis and determined
that_the selected remedy Is cost effective.

The remedy must be effective in the long term.  With proper operation
and maintenance, this remedial action should effectively prevent further re-
leases of contaminants and protect human health and the environment over the
long term.

The comparison of alternatives must take Into account the following factors:

        long-term uncertainties of land disposal;
                 •».
           ls aad£ objectives of the Solid Waste Disposal Act
    • "' persistence, toxlcity, mobility and propensity to b1o-
        aeciMulatft hazardous substances;

        short-and long-term potential for adverse human health
        effects;

        long-term maintenance costs;

-------
                                  -22-
          the.potential  for future remedial action costs If the
          chosen  remedy  were to fall;

         potential threat to human health and the environment
         associated with excavation, transportation, redisposal
         or containment.


 The  Endangerment Assessments, Feasibility Studies and Combined Alter-
 natives  Analysis considered all of these factors during screening of
 alternatives  and recommendation of a final remedy.

 2)   Review of Remedial  Action

 SARA §121(c)-  requires that U.S. EPA review remedial actions that result in
 any  hazardous substances, pollutants, or contaminants remaining at the
 site no  less  often than every five years after Initiating the remedial
 action.  This review should assess whether the remedial action 1s truly   £
 protective of human health and the environment and determine whether any  *"
 further  action 1s necessary.  Because contaminants will remain on these   "r .
 sites, the remedy must  be reviewed every five years.

 B.   Consistency with National Contingency Plan

 SARA requires that remedial actions meet legally applicable or relevant
 and  appropriate requirements of other environment laws.  These laws include:
 the  Toxic Substances Control Act, the Solid Waste Disposal Act (KCRA), the
Clean Water Act (CWA), the Safe Drinking Water Act (SDWA) and any State law
 which contains stricter requirements than the corresponding Federal law.

A "legally applicable"  requirement 1s one which would legally apply to the
 response action If that action were not taken pursuant to §104 or §106 of
CERCLA.  A "relevant and appropriate" requirement 1s one that while not
 "applicable" 1s designed to apply to problems sufficiently similar that their
 application Is appropriate.  Legally applicable and relevant and appropriate
 requirements arc referred to as ARARs.
        r • .
Followln&fs a description of State and Federal environmental laws which po-
 tent1anj£«re> legally applicable or relevant and appropriate to different
 component* of the remedy, and an explanation of how this remedial action meets
 those requirements.

-------
                                 -23-
1)  Soil/Closure Requirements

Final RCRA" closure and post-closure requirements are ARARs for NSL  and ECC.
The State  administers closure and post-closure programs which are substan-
tially equivalent-to the Federal RCRA requirements.

Indiana's  closure and post-closure regulations include performance-based
standards  which state that the sites be closed in a manner which:

     -  minimizes the need for further maintenance, and

     -  controls, minimizes, or eliminates to the extent necessary  to
        protect human health and the environment, post-closure escape
        of hazardous waste, hazardous waste constituents, leachate,
        contaminated rainfall or hazardous waste decomposition products
        to the ground or surface waters or the atmosphere.

These regulations also require that the cap minimize liquid migration, mini
mize maintenance, promote drainage, accommodate subsidence and have a per-
meability  less than or equal to any bottom Uner or natural subsoils.
Indiana's  closure and post-closure requirements change periodically to
fleet the  latest Federal RCRA requirements.  The more stringent
regulations in effect at the time of remediation will be the ARAR.

2) Ground  Water and Leachate Collection

The State  of Indiana has regulations which establish minimum water
quality criteria for all the waters of the State Including ground water.
In addition, the State has a nondegradatlon policy which maintains  that
existing and_gotent1al uses of water must be protected.  Finally,
both RCRA  arid the Indiana Environmental Management Act require that
measures be taken to prevent the release of contaminants into the ground
or surface water which would threaten human health and the environment.

Ground water beneath the sites discharges Into the unnamed ditch and
Flnley Creek, which flow Into Eagle Creek Reservoir.  After remedial
construction, the sites will be capped nearly to the edge of the
rerouted creek.  Contaminated ground water entering Flnley Creek
potentially affects aquatic life 1n the creek, people eating fish
caught 1 it  the creek *~ and people drinking water from Eagle Creek
Restrvofr* The French drain system will Intercept contaminated
ground witer before 1t discharges to Flnley Creek.  This system will-
cont1ntM»ta b* effective 1f contaminant concentrations Increase.
Access restrictions and deed restrictions will prevent Installation
of water supply wells on the sites upgradient of the creek.  It 1s
unlikely that Flnley Creek Itself will be used as a steady source of
drinking water, given Its variable flow and the availability of other
supplies.

-------
                                 -24-
Table  1, which 1s an updated version of Table 2-4 In the CAA, lists
calculated organic and Inorganic leachate and ground water contaminant
concentrations developed from data collected during the RI.  It  also
lists  numeric standards and criteria which are potentially relevant
and appropriate-to these contaminants under the circumstances:

    -  1/10 96 hour l£ 50 for aquatic life
    -  Ambient Water Quality Criteria developed under the Clean Water Act
         - protection of freshwater aquatic life
         - human consumption of contaminated aquatic organisms
         - human consumption of contaminated drinking water
    -  Maximum Contaminant Levels (MCLs) for public drinking water
       supplies, developed under the Safe Drinking Water Act
    -  Maximum Contaminant Level Goals (MCLGs) developed under the Safe
       Drinking Water Act

The stream criteria shown in Table 1 have been determined to be  the
major  ARARs for ECC/NSL to protect aquatic life In Flnley Creek, as
specified-1n the current State of Indiana present use designation -
partial body contact, warm water fishery.  These four standards
Include 1/10 of the 96-hour LC 50, from State of Indiana Water quality
Standards, 330 IAC 1-1; and Protection of Aquatic Life, Acute and     |"
Chronic, and Consumption of Aquatic Organisms, from the CWA.      •    **

Contaminant concentrations at or below 1/10 of the 96 hour LC 50 and, J[
ambient water quality criteria for aquatic life wiTl be used to
protect aquatic organisms living 1n Flnley Creek.  The fourth set of
criteria, for water which supports fish that may be eaten, is also
an ARAR.  Where the four criteria differ for the same chemical,  the
lowest lev*! has been chosen for the target level to ensure maximum
protectlveness.  Contaminant concentrations 1n at least one ground
water monitoring well have exceeded these levels.  Since, at low flow
conditions, the levels 1n Flnley Creek would nearly equal the concen-
trations In the ground water, the ground water needs to be collected
and treated.

These  criteria, as ARARs, are consistent with RCRA.  The application
of the stream standards mentioned above 1s substantially equivalent
to RCRA ACLs.  RCRA requirements for corrective action are also
considered an ARAR.  Under 40 CFR 264.100, a corrective action  program
Cground- water collection system) meets RCRA requirements for corrective
action*

The last three sets of numeric criteria on Table 1 (Drinking Water
Standards) are ARARs for Flnley Creek as a tributary to Eagle Creek
Reservoir.  Consequently, Flnley Creek water should not contain
concentrations of contaminants that would result In levels hazardous
to human health at the water,Intake 1n the reservoir.

-------
                                 -25-
 In Table 1. the standards and criteria selected by this process are
 underlined.for each contaminant.  As remedial  action progresses,
 these benchmark levels must be reviewed because the underlying
 standards and criteria change over time as scientific knowledge
 Increases.

 One last set of standards may be an ARAR for ground water flowing
 beneath the sites.  RCRA ground water protection standards (40 CFR
 264.92) and concentration limits (40 CFR 2.64.94) apply to the
 ground water at regulated facilities that treated, stored, or disposed
 of hazardous waste 1n surface impoundments, waste piles, land treatment
 units, or landfills, after November 19, 1980.

 3)  Treatment and Discharge of Collected Ground Water and Leachate

 The Clean Water Act limits discharges to navigable waterways.
 Individual discharges are regulated through National Pollutant
 Discharge Elimination System (NPDES) permits.   The State administers
water quality program which Is substantially equivalent to the
 Federal NPDES requirements.  The discharge limits established in the
 NPDES permit are designed to preserve the present use designation of
 the receiving waters and potential downstream uses.  Finley Creek Is
 currently designated as a partial body contact, warm water fishery.
 The NPDES regulations are an ARAR for effluent from Superfund site
 treatment plants which discharge offsite.  The State permit require-
ments for constructing a treatment plant are an ARAR.  The flow
 used to determine the discharge limits Is the Q7, 10 flow of Finley
Creek, which given the limited drainage area Is assumed to be 0.0
 to O.l.cfs. ^-Therefore, no mixing zone applies to Finley Creek when
calculating discharge limits.  Water quality-based NPOES permit
 limits will be based in part on the stream criteria contained in
Table 1 and may Include more stringent limits or whole effluent
 toxicity limits to protect against Interactive effects of toxicants.
 New State regulations have been preliminarily adopted regarding
water quality standards and mixing zones.  The regulations having
the effect of law at the time of the permit application will
 be utilized.

 4)  Statfc»-95 Actiwr
   • r    ^liv,.-
 In addition-to the RCRA closure and post-closure requirements that
 are an Al&Ufefor tht site, Indiana has taken enforcement action against
 NSL (CanstrN*. N-95) to close the facility and undertake certain
 actions which would prevent the release of contaminants from the
 site.  The specific measures that are required Include:

  . -  Installation and continued operation of a perimeter leachate
      collection system

   -  construction of a slurry wall or different technology to pre-
      vent off-site migration of contaminated ground water

   -  long term monitoring

-------
                                 -26-



    -   Installation  of a perimeter security fence

    -   construction  of run-on and run-off controls

Although .the-order  calling for these actions is presently being litigated,
Indiana believes that these should be considered as an ARAR for remedia-
ting NSL.  The proposed remedy meets or exceeds these requirements.

5)  Rerouting Surface Water

The selected remedy will be implemented so as to minimize potential harm
and avoid adverse affects to the site in accordance with Executive Order
11988, "Floodplain Management," and Executive Order 11990, "Protection of
Wetlands."  The natural and beneficial values of floodplains will  be
enhanced.during the implementation of the selected remedy.

Finley Creek will be rerouted along the southern boundary of NSL in
order to move the surface water further from the source of the con-
tamination.  The rechannelization of Finley Creek will meet permit
requirements of the Indiana Department of Natural Resources as
stipulated in the Flood Control Act (13-2-22).  The rechannelization
will be conducted 1n a manner which will not cause undue restrictions  t
on  the capacity of the floodway.  The streambed and banks will be      «k
rehabilitated.                                                         I .

6)  Ground Water Protection

The glacial till water-bearing unit beneath and surrounding ECC/NSL
constitutes a Class II aquifer.  The ground water from underneath  the
sites generally flows to the south or southwest and discharges
into~F1nley Creek.  The selected remedy will not restore the
glacial till unit underneath the sites.  However, it will prevent
ground water withdrawal  onsite as well as preventing contaminants  from
migrating either Into Finley Creek or, however less likely, into the
downgradlent portion of the glacial till unit.  This portion of the
glacial till needs to be protected because it Is outside the zone of
deed and access restrictions and Is currently used for drinking water.
The zoning in this area would allow the ground water to be further
utilized for either Industrial  or potable drinking purposes.  The
potential users of this supply would also become potential receptors
to contaartnants.

The prevention of contaminant migration which 1s achieved by the pro-
posed- remedy Is therefore in accordance with U.S. EPA's Ground water
Protection Strategy of August 1984.  It would also Insure that the
State's drinking water and Industrial water standards would not
be jeopardized thus adhering to Indiana's nondegradation policy.

-------
                                  -27-
 7)   Onslte Construction Activities

     The onsite  construction  activities at the site will create a
     significant amount of fugitive dust.  In accordance with State
     of Indiana  Rule  325 IAC  6-4-6, every available precaution will
     be taken  during  construction to minimize fugitive dust emissions.

 IX.    Consistency with National Contingency Plan

 The  National  Contingency Plan, 40 CFR Part 30U.68(i)(1), states that
 the  appropriate extent of remedy shall be a cost-effective remedial
 alternative that effectively mitigates and minimizes threats to and
 provides  adequate protection of public health and welfare and the en-
 vironment.  The selected remedy will attain or exceed applicable or
 relevant :and  appropriate Federal public health and environment re-
 quirements that have been identified for ECC and NSL.  Based upon the
 analysis  of the options, State and Federal environmental requirements,
 and  the comments received from the public and the State, the recommen-
 ded  option has  been  determined to be consistent with Section 30U.68.

 X.   Operation and Maintenance                                          4-

 Maintenance will be  required for the cap because of erosion, freeze/   f"
 thaw,  and  landfill settlement.  Regular mowing of grass on the cap 1s  1
 required.  Routine Inspections of the cap surface and the leachate and-..
 ground water  collection systems will be required semlannually.  Replace-
 ment of collection system pumps, cleaning of collection system drains,
 and  refurbishment of monitoring well screens will be undertaken as
 necessary.

 The "treatment system will require full-time operators to perform testing
 and maintenance, to  adjust chemical and carbon feed rates, and to ensure
 that all process units are functioning properly.  To provide for reyular
 maintenance or  in the event  of treatment system failure, a lUU.UOU-gallon
 holding tank  1s Included.  This tank provides a 2-day holding time for
 untreated leachate and ground water.


 XI.  Comunlty  tWatJons/Responsiveness Summary

 In Audjijitf 198** a public meeting was held in Zionsville to familiarize
 the pafcTte with? the  Superfund process and the work- that was to begin
 durf rtf^tfce Rt for Northside.  A second purpose for that meeting was
 to exp1a4n> th*  surface cleanup and RI work that had been done at
 Env1ro-Chem.  After  the RIs were completed for both sites, a joint
 public  meeting  was .held In May 1986 to explain the results of the
 RIs.  All comments that were received after this public meeting were
 reviewed and  considered 1n the preparation of the FSs.  A Fact Sheet
 updating the  progress on the FSs was sent to all groups and individuals
 on the  mailing  list  1n Fall  1986.  When the FSs were completed in
 December 1986,  another public meeting was held.  A seventy-eight
 day public comment period was available during which comments on both
FSs and the CAA were accepted.

-------
                                 -28-
Local residents are extremely concerned that a permanent remedy be Implemen-
ted as soon as possible at the sites.  U.S. EPA has met with a local  environ-
mental group to discuss Issues related to the sites.

The responsiveness summary is attached.

XII. Deletion from the NPl

Upon implementation of the selected remedy, ECC/NSL will be probably classi-
fied as Long Term Response.


-------
*NSUCCC
                                                             '#
                                                                                                      FIGURE 1
                                                                                                      ECC/NSL ROD

-------
                                                                       PROCESS
                                                                       DRAINAGE
                                                                       SUMP
                                                      COOLING
                                                      WATCH
                                                      POND
                                                      (FILLED]
       if: \
TANKS

WOOOKNCI

STMAMOtOWmi PENCE
                                                              KAUIINPHT
                                                                          FIGURE 2
                                                                          ECC^MLMOO

-------
-«••-GOMTOUIIJMI
•*» umonu. «o«n»«»i
—— emu*
XV HMMtHOIUBMIOQITCNIU
•—"• o*tm*atonat
          ll«^iljll«»»i».

         VOO I.. ••»•» JSt^MMltMi
                          FIGURE 3
                          ECC/NSL ROD

-------
                                                               Table 1
                                    *
 HATER QUALITY CRITERIA APPLICABLE TO TREATED  LEACHATE AND GROUND MATER DISCHARGE FOR RECOMMENDED ALTERNATIVE
                                                                        Stream Criteria   (ug/1)
Drinking Water Standards (ug/1)
1,1.1-Trlchloroethane
1.1.2-THcMoroethant
Chlorofom
Benzene
Ethylbenzene
Nethylene Chlortdt
1.1-Olchloroethene
TrlchlonMthen*
Tetrachloroethene
Toluent
Phenol
4-Chloro-3-Nethyl
        phenol
BI$(2-Ethyl  Hexyl)
      PhthaUte
Average
Leactiate
Concentration
(uff/1)
1
-
-
106
101
1.250
3
1
-
26
149
62
181
Average
(round Hater"
CoJKMtrattoii
(ug/1)
2.300
1.5
11
104*
350
$.900
3<
5.800
230
1.800
4.400
.1
11
1
One-Tenth
96 hr LCd
5.280
9.400
-
2.440
4.230
19.300
-
4.020
1.840
3.400
570
1.0
w
Protection of
Aquatic Life*
Acute Chronic
18.000*
18.000* 9.400*
28.900* 1.240*
5.300*
32.000*
-
30.300*
45.000*
5.280* 8(0*
17,500
10.200 2.560*
3D*
P P
Consumption of
Aquatic
Organises*
1.030.000*
41 .8b
15.7b
40f>
3.280*
15.7b
1.85"
80. 7b
8.85b
424.000
769.000*
-
50.000
Naxloun
Contanlnant
Levels'
(MCLs)
200
(-)
100"
5
(-)
(-)
7
5
_n
-
(-)
• -
(-)
t
AWQC
Drinking
Uater9
Only
19.000*
0.6b
O.l9b
0.67b
2.400*
0.19b
0.033b
2.8b
0.8b
15.000b
3.5UO*
3,000
21.000*
Naxlnun
Contdnlnant
Level
Goals
(HCLGs)
200
-
-
0
68flJ
-
7
0
.n
2,OOflJ
-
-
_

-------
-2-
Vinyl Chloride
1.2 - Dtchloroethane
01-n-butyl Phthalate
Dtethyl Phthalate
Dimethyl Phthalate
Napthilene

Arsenic
Chromium
Copper
Cyanide
Iron
Lead
Nickel
Zinc
                        12
                        33

                        20

                         6
                        18
                        33

                    32.600
                        45
                        76
                       123



•
(1
Stream Standards
t.
i 'Average
tfpund Hater
Cjfacentration
(ug/1)
T
&;• 18
-
9
7
7
28'
25
5
4
15
2.550
22
71
31
One-Tenth Protection of
Aquatic Life*
96 hr LC<* Acute Chronic
.
48.000
P
52.100P
33 .POOP
15.000 2.300
360
16
42e
22
-
262C
3.700C
687C
-
2.000
P
P
P
620
190
11^
26_c
5.2
1.000
lp_c
192C
47_c
Consumption of
Aquatic
Organisms
525
243
154.000*
1.800.000*
2.900.000*
-
0.0175
3.433.000
-
-
-
-
100
-


i
i
Drinking Hater Standards (ua/ll
Maximum
Contaminant
Levels'
(MCLs)
2
5
(-)
(-)
(-)
(-)
50
50"
1.000'

300 1
50
-
5.000
;AWQC
Drinking ,
WaterS
Only
>
0.94b
44.000*
434.000*
350.000*
-
0.0025°
50
1.000
200*
-
50*
15.4*
5.000
Maximum
Contaminant
Level
Goals
(MCLGs)
0
0
-
-
; -

50J
120k
1.300J
-
-
20J
-
-

-------
  -3-



a
 Based on toxlclty concentration.
b                                *
 Based on carcinogenic protectIQQ.                    •'
c    •                       >•$'*.
 Contaminant concentration tottM on pater hardness of 250mg/l CaCOa equivalent.
d     ,,                    ^»T™ W- T                 I                      .        "                  •
 Rased on published 96-hour Median lethal concentration, (Verschueren, 1983).  Use of one-tenth of the 96->hour'median lethal
concentration Is based on State of Indiana Hater Quality Standards, 330 IAC 1-1.                         '
e                      .                                             •                                                • .
 1980 Federal Ambient Hater Quality Criteria, as revised In bOFR 30784. July 29,  1985.

 Parentheses Indicate that EPA must promulgate an MCL for that contaminant
 under the Safe Drinking Mater Act Amendments of 1986.
9
 1980 Federal Ambient Mater Quality Criteria.
h
 Average ground water concentration Includes projected ground water concentration of selected
 contaminants In till unit at ECC (see ECC RI Report. Chapter 5 (Narch 14, 1986)  and existing
 ground water concentrations at NSL perimeter (see NSL FS Report, Appendix A).

 Concentration not estimated for ground water beneath ECC.   Concentration represents NSL  ground
 water concentrations only.
J
 Proposed Maximum Contaminant Level Goal
k
 Total Chromium

 The MCLs for copper and Iron are secondary NCLs, based primarily upon aesthetic  qualities of water.
m
 The MCL for chloroform Is a final  MCL for total tribalomethanes.
n
 The MCL and MCLG for tetrachloroethene are expected to be proposed in December 1987 and  to become final  in June 1988.
o
 These are lowest observed effects levels (LOELs).
P
 The protection of aquatic life criteria for phthalates,  as a class, are 940 ug/1  (acute  LOEL) and 3 ug/1 (chronic LUEL)
     r              ~*                        r                  .1     ,

 	 Underline designates the lowest  stream criteria.

-------
                             Responsiveness Summary
                              Combined Alternatives
                                 Analysis Report
                         Northside Sanitary Landfill and
                           Environmental Conservation
                            and Chemical Corporation
                                     Indiana

                                   WA28-5LH2.0
                                   WA77-5L30.1

                               September 24, 1987
6LT614/26

-------
CONTENTS

                                                       Page
1.   Introduction                                         1
2.   Overview                                             2
3.   Community Involvement Activities                     2
4.   Summary of Public Comments Received During
     Public Comment Period and U.S. EPA Responses         4
     4.1  Relationship between U.S. EPA and
          State of Indiana Efforts                        4
     4.2  Status and Responsibilities of Northside
          Sanitary Landfill                               5
     4.3  Time Frame for Initiating Cleanup               5
     4.4  Responsibility for Paying Costs                 6^
     4.5  Combination of the Sites                        611
     4.6  Remedial Investigation Data                     7
     4.7  Endangerment Assessment                        15
     4.8	Hydrogeology                                   18
     4.9  Technologies and Costing Methods               41
     4.10 Remedial Alternative Preferences               50
Appendix A.  Evaluation of Indianapolis Water Company
             Data
Appendix B.  Bibliography of Comments Received
GLT61T4/2T

-------
                   RESPONSIVENESS SUMMARY
   NORTHSIDE SANITARY LANDFILL/ENVIRONMENTAL CONSERVATION
       -  .    AND CHEMICAL CORPORATION, INDIANA
       --•  - -         1.  INTRODUCTION

The U.S. Environmental Protection Agency (U.S. EPA) has
gathered information on the types and extent of contamina-
tion, evaluated remedial measures, and recommended remedial
actions at the Northside Sanitary Landfill (NSL) and Environ-
mental Conservation and Chemical Corporation  (ECC) sites.
As part of this process, several public meetings were held
to explain the intent of the project, describe the results,
and receive comments from the public.  Public participation
in Superfund projects is required in the Comprehensive Envi-
ronmental Response, Compensation and Liability Act of 1980
(CERCLA), as amended by the Superfund Amendments and Reau-
thorization Act of 1986 (SARA) and the National Oil and
Hazardous Substances Contingency Plan (NCP).  Comments
received from the public are considered in the selection of
the remedial action for the site.  This document summarizes^
the comments received and describes how they were incorpo- fb
rated into the decisionmaking process.                     l"

The responsiveness summary has three sections:

   .  o    Section 1.  Overview.  This section briefly pre-
          sents the U.S. EPA's recommended alternative for
          remediation at the Northside Sanitary Landfill
        	(NSL) and Environmental Conservation and Chemical
   ~      Corporation (ECC).

     o    Section 2.  Background on Community involvement and
          Concerns.  This section provides a brief history
          of community interest and concerns raised during
          remedial planning activities at the site.

     o    Section 3.  Summary of Public Comments Received
          During Public Comment Period and U.S. EPA Responses.
          BotB oral and written comments are grouped by top-
          iesjuL. U.S. EPA responses to these comments are also
          provided.
In ad&itiott to the above sections, Appendix A, included as
part of this responsiveness summary, identifies the U.S. EPA
evaluation of additional information obtained from the Indiana-
polis Water Company during the public comment period and the
results of a site reconnaissance performed in June of 1987.

The detailed transcript of the Feasibility Study public meet-
ing and the written comments are not included in the report.
They are available for public inspection  from U.S. EPA

-------
Region V in Chicago, Illinois and at the repositories at the
Hussey Memorial Library and Zionsville Town Hall.

                        2.  OVERVIEW

During the -public comment period, U.S. EPA presented nine
alternatives in the Combined Alternatives Analysis  (CAA)
Report, dated December 5, 1986, to remediate the potential
for exposure to contaminants from the NSL/ECC sites and the
no action alternative.  U.S. EPA recommended the implementa-
tion of the alternative that included access and deed restric-
tions on the NSL and ECC sites; capping of both sites with a
RCRA compliant cap to restrict direct contact with contami-
nated soils, to stabilize and maintain the surface of the
landfill, and to minimize infiltration of rainwater and leach-
ing of contaminated soils; continued monitoring of the sites
to verify the effectiveness of the implemented alternative;
the installation and maintenance of a leachate collection
system around the perimeter of the landfill; the installa-
tion and- maintenance of a groundwater interception system
which would collect groundwater coming from the sites before
it reaches Finley Creek; the treatment of collected leachal
and groundwater to remove contaminants; the rerouting of
unnamed ditch to the west of the ECC site, and rerouting oi
Finley Creek further south of NSL.  The U.S. EPA also
explained that additional Preliminary Design and Design work.
will be conducted to aid in implementing the alternative.

Six letters were received expressing support of the U.S. EPA's
alternative.

The~~three~Potentially Responsible Party (PRP) Steering
Committees, the landfill owner, and 11 other PRP's com-
mented, in essence, that not enough information is available,
or not enough of a health threat exists to take any action
other than access restrictions, some form of leachate collec-
tion, capping of the landfill, and monitoring.

            3.  COMMUNITY INVOLVEMENT ACTIVITIES

The chronology of community involvement activities in the NSL
    BCC sites isv as follows:
    %'                           •
     JtHy 21, 1983—Press release for ECC PRP Settlement.

     August 23, 1984—Press release for Northside/
     Enviro-Chem PuElic Meeting Announcement.

     August 1984—Fact sheet announcing' Northside RZ/FS
     investigation distributed.

     August 24, 1984—Press release for update meeting on RI
     activities.

-------
     September 4, 1984—Public meeting to explain planned
     Remedial Investigations for ECC and NSL.

     -March 1986—Fact sheet distributed describing results
     of RI's.Reports sent to information repositories,
     local 'officials and concerned citizens.

     May 14, 1986—Press release for May 21 public meeting
     on RI's.

     May 21, 1986—Public meeting held to explain RI's and
     take comments.

     June 1986—Community Relations Plan finalized.

     September/October 1986—Fact sheet updating RI/FS activi-
     ties at NSL and ECC distributed.

     December 1986—-Fact sheet distributed to announce recom-
     mended alternative.  Fact sheet described alternatives
     considered.

     December 5, 1986—Press release for public meeting Decim-
     ber 17, 1986 for FS.                                  f
                               •  •       '                   * "
     December 17, 1986—Public meeting held to explain FS aUd
     take comments.

     February 4, 1987—Press release announcing comment period
     extension for FS's.

     February 18, 1987—Public comment period extended at
     request of State, citizens' groups, and PRP's.

     February 28, 1987—Public comment period ends.  Comment
     period lasted 78 day*.

Telephone contact was maintained with local officials, citi-
zens' groups, and media throughout the RI/FS.  Press releases
and fact sheets- were distributed to media, local officials,
and residents-on 0.S. EPA's mailing list.  Fact sheets and
vepoztsjt w«r« sent to repositories at the Huasey Memorial
Library and lionsville Town Hall.  The Indiana Department of
ZnvinmM&tal Management (IDEM) participated in the public
meetings'*  .

Several PRP's requested that the public comment period be
extended by periods ranging from 30 days to 6 months.  The
comment period was originally set for 55 days after the pub-
lic meeting on the FS, rather than the required 21 days, to
accommodate expected public interest.  The ECC and NSL Reme-
dial Investigation  (RI) Reports, which were the subject of a
public meeting on May 21, 1986, contain the results of

-------
 sampling activities and the evaluation of potential public
 health threats and environmental effects.  The RI's were
 available-for 278 and 265 days, respectively,  prior to the
 December 17, 1986 public meeting on the FS's.   These data
 were used to develop the FS's.   The FS's were  available for
 5 days prio'r to the December 11, 1986 public meeting.  After
 the public meeting on the FS's  the comment period was extended
 by an additional 18 days for a  total of 78 days.   A longer
 extension was not feasible given the U.S. EPA's commitment
 to make a decision in the 1987  fiscal year and to move ahead
 with the remediation of NSL/ECC as quickly as  possible.

        4.  SUMMARY OF PUBLIC COMMENTS RECEIVED DURING
        PUBLIC COMMENT PERIOD AND U.S. EPA'S RESPONSES

 Comment* raised during the NSL/ECC Feasibility Studies (FS's)
 and Combined Alternatives Analysis (CAA) public comment period
 are summarized.  The comments received during  the public com-
 ment period are categorized by  the person, forum or company
 for whom' the comment was prepared.

 There were a number of comments submitted on liability for f •
 remediation of the sites.  These comments are  not considered
 to be germaine to the selection of the remedy  and are beyonJT
 the scope of this Responsiveness Summary.  There were also a>
 number of comments submitted on regulatory requirements and":
 ARAR's.  These are specifically addressed in the Record of
 Decision.  A bibliography of comments received is included
 as Appendix B.

 4.1	RELATIONSHIP BETWEEN U.S.  EPA AND STATE OF. INDIANA
 EFFORTS'

 Comment.   Has the U.S. EPA worked with the State of Indiana
 to prepare the FS and CAA reports?  Are the alternatives
 favored by U.S. EPA and the State of Indiana compatible?
 Does the Indiana Department of  Environmental Management
 (IDEM)  now agree with U.S. EPA's findings?  (NSL/ECC Decem-
 ber 17, 1986 Public Meeting)

 U.S. BPA Response.  The State of Indiana has reviewed drafts
 and a&ssieated on the FS's and CAA documents and their comments
 were/£$tte6rporated.  There have  also been several meetings
 betveiN*: the U.S. EPA and IDEM,  and frequent contact between
 the-a.Si  BPJk and IDEM representatives for the  site.  The IDEM
 has been involved in the remedy selection process and believes
 that the U.S. EPA's Recommended Alternative is a viable option
 for remediating both sites.

'On December 16, 1986, the State of Indiana sent official noti-
 fication to the U.S. EPA of its concurrence with the remedy.

-------
4.2  STATUS AND RESPONSIBILITIES OF NORTHSIDE SANITARY
LANDFILL"

Comment.  Will NSL continue to operate during construction?
Will the landfill be closed?  Will the landfill remain in its
current -location?  Why should NSL be included in the plans
for remediation?  What levels of contamination indicate that
NSL should be included in the remediation plans?  (NSL/ECC
December 17, 1986 Public Meeting)

U.S. EPA Response.  Implementing the remedial alternative pro-
posed would necessitate closing of the landfill.  The landfill
would remain in its present location and be capped with a
fence around it and leachate and groundwater collection sys-
tems in place.  There would also be a treatment plant to treat
collected groundwater and leachate.

During the remedial investigations contaminants were found
in the monitoring wells at concentrations which exceed cri-
teria for the protection of human health and environment.
Concentrations of contaminants were also found in surface
water samples which exceed criteria for the protection of   + .
human health and the environment.                           |

The concentrations of contaminants found in the monitoring  I
wells and surface water can be found in Appendix Tables A-4r
A-7, and A-8 Volume 1 of 2 NSL Final RZ.

4.3  TIME-FRAME FOR INITIATING CLEANUP

Comment.  How long will it be before the actual site cleanup
begrns antt can the time-frame be expedited?  Can the U.S. EPA
start the remedy after the Record of Decision  (ROD) is signed
and before an agreement is reached with PRP's?  Is there a
time limit on negotiations, after which cleanup will begin?
(NSL/ECC December 17, 1986 public meeting)

U.S. EPA Response.  Assuming that negotiations with PRP's are
completed, the ROD is signed and the design is finished it
could taxe from 1 to 2 years to construct the groundwater
interception system and 2 to 5 years to construct the RCRA
cap.

As loae* a* tha. U.S. EPA is still negotiating with the PRP's
the iapleaentition (actual construction) of a remedy will not
begin. -Th* U.S. EPA will give the PRP's a reasonable oppor-
tunity to negotiate a settlement but it is not going to be
open ended.  The U.S. EPA recognizes the concern about decid-
ing whether the PRP's or.the U.S. EPA will do the remediation.

-------
4.4. RESPONSIBILITY FOR PAYING THE COSTS

Comment:. -After any necessary allocations have been made, the
cost ..attributable to any nonsolvent PRP should be borne by
the U.S. EPA.

Who will pay the cost of the cleanup, the potentially respon-
sible parties  (PRP's) or the taxpayers?  Are the PRP's that
previously settled released from liability?  Why weren't all
PRP's given the chance to settle at that time?  (Mersman;
NSL/ECC December 17, 1986, public meeting)

U.S. EPA Response.  Under the Superfund law the U.S. EPA will
take every course available to negotiate settlements.  Where
need be the U.S. EPA will take enforcement action against PRP's
and may'draw on the fund set aside by Superfund.

In 1982 the Enviro-Chem site was covered with stacks of drums
and tanks containing hazardous waste.  The U.S. EPA wa* focus-
ing on that acute problem so a settlement was reached with
the known PRP's for surface cleanup purposes.

Not all of the known PRP's participated in the cost of sur
face cleanup at Enviro-Chem.  The PRP's that did participa
in the surface cleanup were released from liability for f
ther surface work, but they are not released from liability -
for the groundwater problem.

The U.S. EPA found out about other ECC PRP's at later date.

4.5  COMBINING THE SITES

Comment.  The application of CERCLA section 104(d)(4) to com-
bine the NSL and ECC site* is inappropriate.  It appears that
the only groundwater contamination involved is that which is
attributable to the NSL site.

Although location of the two sites may be relevant to some
circumstances, these are essentially two different sites, and
combination i» inappropriate.

            containination levels are much greater for ECC
          the. two areas are vastly different in size, hence
            of the ECC site should be accomplished separately
         NSC lite (Mersman; Ferro Corp.; NSL Steering Commit-
tee; ECC Steering Committee).

U.S.EPA Response.  The proximity of the two sites to each
other is one major reason for combining the sites and imple-
menting an overall remediation for both*  A second consid-
eration in the contaminated environmental media are common
to both sites, such as groundwater and surface water, and
the difficulty of identifying the source  (ECC or NSL) of

-------
some of the observed groundwater and surface water contami-
nation.  Similar chemicals, byproducts, and waste were either
stored or-disposed of at both sites.  Also since both sites
had similar status with respect to regulatory permits, reme-
diation needs for both sites are similar and combination of
the sited for the purpose of remediation seems reasonable.

A third consideration is that a combined remedy is more cost-
effective than two individual remedies for these sites.  The
monitoring system, the groundwater collection system, and the
treatment system are cheaper to design and operate if the
sites are combined.  The combined remedy will be equally as
protective of human health and the environment as two sepa-
rate remedies.

4.6  REMEDIAL INVESTIGATION DATA

Comment.  The detection levels presented in Appendix A of the
NSL RI Report dated March 27, 1986, are higher than some of
the results reported elsewhere with lower values [sic].  For
example, a value of 4 ug/1 for benzoic acid was reported when
the detection limit is given as SO ug/1.  This is misleading:
and these types of results should be reported as 4±50 ug/1, \
so as not to provide a misconception of water quality.     I

It is truly questionable to consider enforcing minimum levels
for constituents found in the groundwater and leachate whose
minimum criteria is 151 to 4,000 times lower than the detec-
tion limit (NSL, Inc.; Ferro Corp.).

U.S. EPA Response.  The detection limits cited .in the RI's
are contracted for through the U.S. EPA'a Contract Laboratory
Program.  In actuality the more proper name would be con-
tracted quantification limit.  The technology exists by which
the concentration of a contaminant in water can be quanti-
fied down to the nanogram per liter level or roughly part per
trillion level or less depending on the compound of concern.
Even at these lower levels a compound can be detected and
positively identified but the concentration may have to be
estimated which: is then indicated by a J qualifier in data
sunnacy table*.  The criteria is based on the observed
effectifr certain compounds have on various organisms or pro-
jected effect* the compounds could have on humans based-on
ania*i- laboratory experiments.

Comment.  The similar compounds detected in Finley Creek are
not supported by. the analytical data from ECC monitoring well
samples, are not directly related to the ECC site, and do not
constitute a valid reason for requiring 'interception and treat-
ment of groundwater (ECC Steering Committee).

-------
U.S. EPA Response.  The similar compounds detected in Finley
Creek were found not only in ECC monitoring well samples, but
also in ECC subsurface soils and in the contaminated water
samples taken from under the concrete pad on the southern end
of the ECC site and from the sump in the same location.

Compounds similar to those observed in the NSL monitoring well
samples, subsurface soil samples and leachate tank samples
are also detected in Finley Creek.

Comment.  There are discrepancies in the analytical results
due to poor quality control.

All analytical results where field blanks showed substantial
contamination should be stricken from the tables in the
reports.

Methylene chloride is not present due to the site, but rather
is an artifact of the sampling and analytical procedure
(Jones, Inc.; TRW Inc.; NSL Steering Committee).

U.S. EPA Response.  The analytical results presented in the,.
RI's and FS's have been reviewed and qualified.  The specif&
use of contaminant concentrations with a J qualifier is accept-
able.  The J qualifier means that the compound was present  I .
but that the concentration of the contaminant in the environ-
mental media is estimated.  It does not mean that the compound
was not present.

The presentation of all reportable data is important so that
decision makers and concerned parties have a complete data
base- from which to form an opinion on remediation needs.

Methylene chloride is listed as a specific waste product dis-
posed of at the NSL site.  It is also listed as a frequent
laboratory contaminant.  In some samples methylene chloride
concentrations were an order-of-magnitude higher than would
be expected from laboratory contamination.  It is difficult
to completely discount or verify that methylene chloride in
the various environmental media is or is not coming from the
                  the concentrations of methylene chloride
            th* various environmental media during the RI
_*   '	                                          *
are
          Considerably more oil and grease was found in sur-
fac* w*t«r sediments upstream of NSL than downstream [sic].

Of 10 downstream' surface water sediment samples eight had
lower concentrations of lead [sic]; thus, the source of lead
cannot be attributed to NSL, simply because it was found at
a higher concentration'downstream  (Tricil).
                              8

-------
 U.S.  EPA Response.   During Phase I  and II  of the  RI,  sediment
 sampling point SD001 is located upstream on unnamed ditch  and
 SD002 is upstream on Finley Creek.   During Phase  I  sampling
 the oil and grease concentration at SD001  was 600 mg/1  and
 the first sampling point downstream on unnamed ditch  at SD010
 had a concentration of 190 mg/1;  hence in  Figure  4-28 of the
 NSL RI it is noted that the concentration  of oil  and  grease
 in unnamed ditch is not above  background.   SD001  is an
 upstream sampling point for unnamed ditch  and is  not  an
 upstream sampling point for Finley  Creek.

 The upstream Phase I sampling  point in Finley Creek SD002
 had an oil and grease concentration of 350 mg/1.  All Finley
 Creek sampling locations adjacent to and downstream of  NSL
 (5 points)  had oil and grease  concentrations ranging  from
 40.0 to 580 mg/1 which is a 14  to 66 percent increase  over
 the Finley Creek upstream concentration.

 During the Phase II sampling period oil and grease  was  quan-
 tified at one point in Finley  Creek above  upstream  concen-
 trations as was one point in unnamed ditch.   This is  also
 shown in Figure 4-28 of the MSL RI.                        *'

 Lead  is present in the upstream Phase I sediment  samples on A
 both  unnamed ditch and Finley  Creek at concentrations of 10 I
 and 8.6 mg/kg,  respectively.   In Phase I,  samples taken adja-
 cent  to and downstream of the  site  had lead sediment  concen-
 trations ranging from 13 to 31 mg/kg and exceeded the
 upstream concentrations by 30  to 210 percent.  Phase  II
 downstream lead sediment concentrations that range  from 23
 to 37 mg/kg exceed the upstream concentrations of 16  mg/kg
 in unnamed" ditch and 12 mg/kg  in Einley Creek by  50 to
 130 percent.

 These data suggest that there  is a  contribution of  oil  and
 grease and lead between the sampling locations upstream of
 NSL and sampling locations adjacent to and downstream of NSL.

 Comment.   No information is provided regarding the  form of
 cyanide* present (in surface water).  Cyanides were  not  found
 in any*.other sampling media (at NSL).  Therefore, cyanides
 cannot: b« attributed to the NSL site, and  any EPA identified
 risks$&M to its presence are'  invalid [sic]  (NSL  Steering
 Committee).

 U.S.  BPA Response.   The samples were analyzed for total
 cyanide.   Cyanide was found in a sediment  sample  shown  on
 Figure 4-28 and in groundwater samples shown on Figure  4-34
.and 4-84 of the NSL RI. .As shown on Figure 4-24  of the NSL
 RI, cyanide was not detected in surface water samples upstream
 of the NSL site.   The criteria for  the protection of  aquatic
 life  from acute or chronic effects  of cyanide are 22  and
 5.2 ug/1,  respectively.  The surface water concentrations

-------
observed- in Finley Creek exceed the criteria; therefore, the
risks identified are not invalid.

Comment:*  It is unclear if concentrations of lead, PCB's, or
pesticides in soil or sedimentation can be linked directly
to the Landfill (Tricil).

U.S. EPA Response.  Lead does not occur at elevated concen-
trations in upstream sediment or background soil samples.
PCB and pesticide concentrations above detection limits
occur only adjacent to and downstream of NSL.  This indi-
cates a positive relationship between the landfill and sedi-
ment concentrations.

Comment.  The (ECC RI) report assumes that the presence of
any organic compounds show contamination from the ECC site.
No attempt was made to characterize the true background at
the site.  All historical sample tables must be stricken
unless it can be established that the conditions are the
same today as they were on the dates of historical sampling.
Some samples are almost 8 years old (TRW, Inc.).
                                                            * •
U.S. EPA Response.  In the ECC RI the chlorinated hydrocarbons
found in the groundwater in the shallow saturated zone, shaBLow
sand and gravel zone, ECC soils, unnamed ditch sediments. Fish-
ley Creek sediments, and Finley Creek surface water are stated
as likely to be from ECC.  There is no assumption that the
presence of any organic compound offsite shows contamination
from ECC.

Table 4-4 ECC RI shows background concentrations for a number
of contaminants.

The historical information is presented for site background
purposes and historic perspective.  The information is not
used to describe the nature and extent of contamination at
the site as it existed during the remedial investigations.
Therefore, there is no need to strike the historical tables.

Comment*  The ECC RI Table 3-9 does not indicate depths of
monitoriag w*ll* for historical data.  Depths of residential
well*r*r* not indicated (TRW, Inc.).

U.S. llfr'aespons*.  The ECC Monitoring well  (MW) No. 1 is
70 feetdeep and~ECC Monitoring well (MW) No. 2 is 36 feet
deep.  They locations of MW1 and MW2 are shown on Figure 3-5
and the well depths are listed in Table 3-8 of the ECC RI
and in Appendix F of the NSL RI.  Available residential water
well records from adjacent townships around ECC and NSL are
also included in Appendix A Technical Memorandum No. 7 Vol-
ume 2 of 2 NSL RI.  There are also boring logs for the NSL
monitoring wells included in Appendix C of Technical Memo-
randum No. 4 Volume 2 of 2 NSL RI.
                             10

-------
Comment..  The dilution factor of 20 to 1 on ECC FS page 1-3
is too low and inconsistent with the 1,300 to 1 dilution
stated on.page 6-12  (Tricil).

U.S. EPA Response.  The 20 to 1 ratio is calculated on an
areal basis';  Finley Creek's watershed is approximately
10 square miles in extent; Eagle Creek Reservoir is fed by a
watershed of approximately 170 square miles.  Hence 170 to
10 is 17 to 1 or 20:1 rounded off.  Water that is already in
Finley Creek could be diluted 20 times by the time it reaches
Eagle Creek Reservoir.

The 1,300 to 1 dilution ratio is also calculated on an areal
basis.  The ECC/NSL drainage area is about 0.12 square miles.
Eagle Creek Reservoir's drainage area is 160 square miles.
Hence 160 to 0.12 is 1,300 to 1 rounded off.  Therefore,
water that comes from the sites could be diluted 1,300 times
by the time it reaches Eagle Creek Reservoir.

Comment.  References to ECC soils should be stricken unless
U.S. EPA can establish that these soils existed after the
1983-84 remedial work.                                      $

All references to site conditions which no longer exist     §•
should be stricken.                                         1

The inclusion of descriptions of sample* taken on the sur-
face of ECC lacks many details.  If these samples of soils
are not representative then they form an insubstantial base
on which to rest the conclusion that, an FS is necessary.

The "conclusion that there is a source of exposure from the
migration of chemicals through the shallow sand and gravel
aquifer (at ECC) must be stricken since it is also stated
that the alteration of the site characteristics during sur-
face cleanup has made this an unlikely migration pathway
presently or in the future.

Results of the ECC RI do not reflect conditions upon which
additional remedial action could be based since the RI was
conducted over the same time span as initial remedial
The- eCfiecb of remedial measures already undertaken at ECC
have-not beea evaluated.  Thus there is no way of quantify-
ing the> current potential risk posed by the site and the
need, if any, for additional remedial actions.

The statement that analytical results of the  (ECC) RI charac-
terize current site contamination is erroneous in that exten-
sive remedial actions were completed at the site and these
have not been taken into account  (TRW, Inc.; Tricil).
                              11

-------
U.S. EPA Response.  The Phase II soil samples were taken
after the surface cleanup activities were completed  (see
page 3-32 of the ECC RI), refer to Soil Investigation Memo-
randum Subtask 3-4 in Appendix A ECC RI Volume 2.

These data were used to evaluate the nature and extent of
contamination and risks attributable to ECC site soils.  The
soil samples taken during this Phase II of the RI are shown
in Figure 4-2 of the RI.  Therefore, the contaminated sub-
surface soils at ECC still exist.

The description of historic site conditions are helpful to
the reader to understand past activities which have con-
tributed to the existing contamination on the ECC site, and
the past removal activities as outlined on pages 3-32 through
3-37 of ^the ECC RI.

The samples taken on the surface of ECC during the Decem-
ber 12, 1984, Phase III monitoring well sampling trip were
not soil samples but surface water samples of ponded water
on top of the cover which was placed on the northern portion
of the ECC site when surface cleanup activities were         •
completed in August of 1984.  Page 4-60 of the ECC RI gives-f,.
details of the sampling of ponded water. Figure 4-22 shows  *
the sampling locations, and Tables 4-16 and 4-18 show the   | .
analytical results.  Because of the presence of chlorinated^
organic compounds and the location of the ponded water on
top of the cover at ECC, the most feasible source would be
contaminants in the soils below the ponded water.

U.S. EPA did not conclude that migration through the shallow
sand and^ravel aquifer is an unlikely migration pathway.
Rather, as noted in Table 4-13 and on page 4-55 of the ECC
RI, the shallow sand and gravel aquifer (at ECC) is presently
contaminated based on samples taken in November and December
of 1984 after surface alterations were completed in August
of 1984.

U.S. EPA did conclude that migration from the shallow sat-
urated zone to the shallow sand and gravel zone is presently
an unlikely migration pathway due to the upward vertical
gradient.
     •£••-'•      ..                  .    .     .
The eadaagarmeatt assessment takes into account the existing
conditions at the ECC site which includes initial remedial
measures which were completed by August of 1984  (see page 6-10
ECC RI).  Therefore, the risks presented are for the no action
scenario as of the data of the RI.

In summary the initial remedial measures taken at the ECC
site are accounted for and the analytical results used in
the RI do characterize the existing nature and extent of
contamination at the ECC site.
                             12

-------
Comment.  It is stated that contaminants in surface water
will either volatilize, adsorb to sediments, or experience
large dilutions before reaching Eagle Creek Reservoir.  There-
fore, statements on exposures through these routes should be
stricken.  There is no basis for the conclusion or assumption
that if ..contaminants reach the reservoir then users of the
reservoir would be at risk.  No attempt was made to assess
the effects of dilution or to determine the risk scientif-
ically  [sic].  No contaminants have been found in Eagle
Creek . (CAA page 1-8).  If none are in the creek, none can
reach the reservoir (TRW, Inc., Tricil).

U.S. EPA Response.  It is true that, once they reach surface
water, contaminants can volatilize, adsorb to sediments or
be diluted.  The exposures noted in the RI's are based not
only on.projected concentrations but observation of existing
concentrations in Finley Creek.  The risks identified in
Finley Creek are mitigated by implementing the recommended
alternative.  Mitigation of the identified risks in Finley
Creek also protects the drinking water source, Eagle Creek
Reservoir.

Comment.  Water quality criteria should not be applied to   I
groundwater or leachate directly, but to the receiving      jr
stream after dilution.  Indiana regulations have been mis-  f
applied.  "A" mixing zone is defined as:  "An area contigu-^
ous to a discharge where the discharged wastewater mixes
with the receiving waters.  Where the quality of the efflu-
ent is lower than that of the receiving waters, it may not
be possible to attain within the mixing zone all beneficial
uses which are attained outside the zone.  The mixing zone
should nofe be considered a place where effluents are treated.
330 IAC 1-1-10."  Consideration should be given to reclassify
Finley Creek for limited use (NSL Steering Committee;
Tricil).

U.S. EPA Response.  Indiana's present use designation for
Finley Creek is partial body contact and warm water fishery.
Reclassification of Finley Creek to a lower use designation
is against the State of Indiana's nondegradation policy.

A poiot-discharg* of effluents to Finley Creek must meet
potential; Indiana NPDES requirements which would reflect
Finler Creek's periodic low flow (which recurs on the aver-
age of errery 10 years and lasts for 7 days) —(Q- ,Q) of zero
to 0.1 cubic feet per second.  Indiana regulation! do not
allow a mixing zone under these conditions, so there would
be no allowable reductions in the NPDES requirements
resulting from dilution in the receiving stream.  The
criteria which would be applicable for a point-discharge
and/or treatment are, therefore, as presented in the ROD
Table 1.
                             13

-------
Comment.  Methylene chloride in the water samples is not pre-
sent due to the NSL site, but is an artifact of sampling and
analysis.. Therefore, U.S. EPA should not use the presence
of methylene chloride in the water samples to evaluate risk
(NSL Steering Committee) .

U.S. EPA' Response.  Table 6-8 of the NSL RI shows that organic
contaminants other than methylene chloride exceeded drinking
water standards and guidelines, including MCL's, MCLG's, and
CWA WQC's for human health (adjusted for drinking water).
Table 6-9 of the NSL RI presents assessments of risk associ-
ated with drinking groundwater at the NSL site for organic
contaminants other than methylene chloride.

Comment.  Unless EPA can establish that these soils existed
after the 1983-84 remedial work, all reference to these soil
sample results must be stricken as irrelevant.  Reference to
the cooling water pond should be stricken because it was
removed in 1983-84 removal work [sic] (TRW, Inc.).

U.S. EPA Response.  As stated in the ECC-RI, review of soil
laboratory results from samples taken after surface cleanup*-
activities show that inorganic contamination exist to depth*-.
of 3 to 5 feet, and organic contamination as detected to a I
soil depth of 8.5 feet.  In spite of the removal of surface*
soils in 1983-84, there still exists soil contamination
onsite.  In addition, the "On Scene Coordinator's Report"
prepared by Roy F. Weston Inc. (June 14, 1985) explains that
the cooling pond was backfilled with contaminated soil exca-
vated from around the process building.

Continent .'  No attempt was made to characterize what the true
background of organics is at the ECC site [sic] (TRW, Inc.).

U.S. EPA Response.  The organic compounds detected at the ECC
site are man-made, are not naturally occurring, and their pre-
sence indicates the impact of man's activities.

Comment.  In Table 5-6 of the ECC RI, estimated concentrations
of volatile* i* Finley Creek, which are indicated to vary with
the f^owrate, my by a factor of 10.  The flow of Finley Creek
\cariifcby: a factor of 40.  No explanation is given for this
disevfpaacy- (Tricil) .            .
P.8> BfrA Response.  Based on the available data, the  flow  in
Finley CreeJc varTes from less than 0.1 cfs to 4 cfs— which
corresponds to a. ratio of 40.  However, throughout most of
the year, the flow ranges from 0.1 cfs to 1 cfs— which cor-
responds to a ratio of 10.  The latter flow range was used
to calculate the concentrations in Finley Creek since it
provided a more realistic estimate.
                             14

-------
4.7: ENDANGERMENT ASSESSMENT

Comment. - It is arbitrary and capricious to assume that EPA
would not take every effort to prevent the existing condi-
tions at the .site (Jones Chemicals, Inc.).  EPA would never
allow residences to be built on the site nor an occupational
use to occur on the site without some sort of remediation
(TRW, Inc.).  It is unreasonable, arbitrary and capricious
to assume that no fencing, deed notices or use restrictions
would be placed on this property (Ferro Corp.).

The endangerment assessments are based on unrealistic sce-
narios.  The EPA identified risks associated with offsite
surface water, stream sediments, and groundwater are invalid.
Although the report speculates that receptors could contact
the groundwater if potable wells are constructed within the
zones of contamination, the likelihood of that is extremely
small.  There is no factual basis on which to state that
ingestion of fish is an exposure route in this situation
(Jones, Inc.; TRW, Inc.; Ferro Corp.; ECC Steering Commit-  .
tee; Tricil; NSL Steering Committee).

U.S. EPA Response.  As discussed in the RI and FS reports,  •*•
the Endangerment Assessment is performed on the Mo-Action   \
Alternative.  That is, the Endangerment Assessment must
assume that the site remains as it is at present, and that
no remedial actions have been initiated.

The U.S. EPA cannot take any action at a site unless an
unacceptable risk to human health and the environment is
identified.  The site presently has all uses evaluated in
the Endangerment Assessment existing either onsite or adja-
cent to it.  The area around the site is also zoned for
those uses  (ECC RI Figure 6-1 and NSL RI Figure 6-2).  The
surface water in Finley Creek has a present use designation
for partial body contact and warm water fishery which means
the general public can wade in the stream and practice rec-
reational fishing which is assumed to include consumption of
fish caught.  Therefore, it is not arbitrary and capricious
to evaluate* potential exposure using a residential and occu-
pational scenario.
 /•
The ingestion rates used in the Endangerment Assessment for
water and fish are published in guidance documents.  The
ingeation rate for soil averages out to be about 9 ounces a
year for the residential scenario and about 1/10 of an ounce
a year for the occupational scenario.  The ingestion rate for
fish averages out to be about 5 pounds a year.  Nona of these
ingestion rates can be considered overly conservative nor are
they arbitrary or capricious.
                             15

-------
The dermal absorption rate used reflects the skin's ability
to absorb lipophylic compounds.  The rate used was experi-
mentally measured not only by the loss of solute but also by
indirect methods such as byproducts in urine and expired air.
The presentation of risks from dermal absorption of contami-
nants in': surface water and from bathing is to recognize that
this potential exposure route exists and adds to the total
potential risks from the site.

Comment .  The substantial health concerns and environmental
impacts of the proposed alternative have not been addressed
nor has the functional equivalent of an environmental impact
statement pursuant to NEPA been provided (Jeff boat; Rock
Island Refining) .

U.S. EPA Response .  Remedial actions taken pursuant to Sec-
tions 104 and 106 of CERCLA are generally exempt from NEPA
requirements because the EPA has determined that these
RI's/FS's, are the functional equivalent of an Environmental
Impact Statement (EIS) .

The U.S. EPA believes that the remedy screening and selection
process used in the Feasibility Studies and Combined Alter-
natives Analysis for the sites meet CERCLA Section 105(3)
Section 300.68 of the NCP satisfy NEPA requirements.

The U.S. EPA believes also that the various press releases,
fact sheets , public meetings, and lengthy public comment
period satisfy the public involvement requirements of NEPA.

Comment . _ Does the U.S. EPA believe the following findings
from the Norths ide Landfill FS to be true or false:

     o    That the current risk from leachate is negligible?

     o    That current concentrations of contaminants do not
          suggest a threat to aquatic life in Finley Creek?

     o    That the groundwater believed to be discharged at
                 Creek presents negligible risk from of f site
          That the surface water near the site does nofcur
          reatly pose a threat to human health?

(NSL/ECC December 17, 1987 Public Meeting)
.S. EPA Response.  The Endangerment Assessment in the NSL
I states:  fc Comparison of current surface water concentra-
U
RI
tions to Ambient Water Quality Criteria and 96-hour LC50
values does not indicate any chemicals which exceed those
criteria."  This statement is made in reference to Table 6-13
NSL RI and is specific to organic chemical criteria as they  •
                             16

-------
relate to aquatic life.  The table does not reflect what dis-
charge limits of treated effluent would be with respect to
NPDES requirements nor are inorganic water quality criteria
or water quality criteria for the ingestion of aquatic orga-
nisms for the protection of human health presented.

The statement on page 3 of the NSL FS is a summary of the
Endangerment Assessment in the NSL RI.  The statement:
"Discharge of contaminated groundwater, at current concen-
trations, to surface waters does not present a threat to
aquatic organisms..." on page 1-21 is in reference to aqua-
tic life criteria specific to organic chemicals and not
inorganic chemicals or human health criteria or ingestion of
aquatic organisms.

Table 4-2 of the NSL FS and Table 2-4 of the CAA present
potential limits for discharges to Finley Creek for organic
and inorganic chemicals for the protection of aquatic life
and protection of human health from ingestion of aquatic
organisms from Finley Creek.

Comment.  The generic Ambient Water Quality Criteria used fgr
polyaromatic hydrocarbons (PAH's) in Table 2-4 of the CAA
assumes that phenanthrene and naphthalene are a PAH mixture
and that to be conservative the criteria for benzo(a)pyren<
is used.  In this situation the criteria of 0.0311 ug/1
quoted are simply not applicable (NSL, Inc.).

U.S. EPA Response.  The U.S. EPA agrees that both phenanthrene
and naphthalene are currently not considered carcinogenic
polycyclic aromatic hydrocarbons (PAH's).  However, the Inter-
national—Agency for Research on Cancer (IARC) has not evalu-
ated the risk to humans associated with oral ingestion or
inhalation for naphthalene and there was insufficient evi-
dence of carcinogenic risk to humans for phenanthrene.  The
U.S. EPA Carcinogen Assessment Group (CAG) considers the evi-
dence for carcinogenicity of phenanthrene) and naphthalene to
be inadequate and have assigned them to Group D—not classi-
fied chemical.

The criteria presented for phenanthrene and naphthalene in
Tablet 2-4 of the; CAA are not considered ARAR's which are
tisted in Table 1 of the ROD.  The actual discharge limits
will -fie> established during the NPDES process.

Comment.  "On page 3-10 of the NSL FS, the reasons for rerout-
ing the unnamed ditch and Finley Creek are that:  "This would
route the surface waters away from contaminated areas and
increase the travel time for contaminants to migrate to sur-
face waters.  Relocating the surface waters would also allow
monitoring wells to be installed between Finley Creek and the
contaminated areas."  There are no current U.S. EPA identi-
fied risks due to migration of groundwater to surface waters
                             17

-------
or to direct contact with surface waters.  Therefore, rerout-
ing the* surface waters is unjustified  (NSL Steering Committee).

U.S. EPA Response.  Groundwater in some of the existing moni-
toring wells .exceed ARAR's  (see ROD Table 1).  The discharge
of the groundwater to surface waters would also exceed ARAR's
(see ROD Table 1).  The relocation of unnamed ditch and Finley
Creek are necessary to implement Alternative 5 because the
monitoring system necessarily has to be installed between the
groundwater interception system and Finley Creek to verify
the system is performing correctly.

Comment.  The U.S. EPA identified risks due to pesticides in
leachate sediments, water sediments, subsurface soil, and
sand and gravel groundwater in the southwest corner of the
landfill are due to the prior use of the NSL area as agri-
cultural land and not to the landfill operation (NSL Steer-
ing Committee).

U.S. EPA Response.  The NSL site has been a open dump/land-
fill since sometime between 1955 and 1962 (page 3-9 NSL RI).
Agricultural use of the site ceased sometime between 1962  $
and 1972 based on aerial photographic interpretation.  Pea-|-
ticide concentrations in upstream surface water sediments,
upstream soil samples and groundwater samples have consis-
tently shown no pesticides above detection limits.  Even
pesticides resulted from prior agricultural uses there are
numerous other contaminants observed at the site which are
not attributable to agricultural use.

4.8., HYDHQGEOLOGY

Comment.  A french drain system in the shallow saturated zone
at the ECC site is inappropriate because there is no basis
for the assumption that the zone is generally contaminated.
Several invalid assumptions were made with regard to the
french drain system in the 2CC FS  (ECC Steering Committee;
Tricil).

U.S. BPJfc Resaoaas).  Contaminants were detected in samples of
             groundwater taken from the shallow saturated
          the**extent of the ECC site.  The french drain sys-
tem iifcil proposed 1* the ECC FS to prevent these contaminants
from*migrating outside of the site boundaries.

Calculation* and assumptions related to the french drain sys-
tem are presented in Appendix B of the ECC FS.  Flows to the
drains were estimated from the expected recharge to the soil
unit from precipitation and from upward leakage from the
underlying sand and gravel unit.  Assumptions on aquifer homo
geneity, iaotropy, and height of water table above the drain
were made to estimate drain spacing and not to estimate flow
to the drains.
                             18

-------
Commit.  Groundwater contaminant concentrations projected
to  result from  leaching of soil contaminants at ECC  (ECC Rl
Table  5-5) assume that soil concentrations will not change
with time.  Therefore, the projected groundwater concentra-
tions  are overestimated because the soil contaminants will
degrade* TECC Steering Committee).

U.S. EPA Response.  Discussions of the degradation of soil
contaminants at ECC are presented in Appendix C of the ECC
RI, and a summary of environmental behavior of organic com-
pounds in surface soils is presented in Table 5-4 of the ECC
RI.  This table indicates that some degradation and trans-
formation process are insignificant while others are possi-
ble and even significant.  Degradation processes depend on
site-specific conditions and are difficult to quantify.
Therefore, for  the purpose of estimating groundwater concen-
trations resulting from leaching of soil contaminants, it was
assumed that degradation of soil contaminants would be insig-
nificant.

Comment.  The estimated travel times to surface water of con-
taminants from  ECC are longer than the expected degradation^
times of the contaminants.  Therefore, the projected concen4*
trations in surface water resulting from discharge of con-  |
taminated groundwater are overestimated, and do not reflect*
any degree of imminent hazard from the site  (ECC Steering  *"-"
Committee; TRW, Inc.; Tricil.

U.S. EPA Response.  The travel time of 300 and 800 years for
TCE at ECC are  estimates of travel time from the northwestern
portion of the  site to the unnamed ditch and Finley Creek
(ECC RI, page 5-13).  The estimated travel time for TCE from
the eastern portion of the site to the unnamed ditch ranged
from 20 to 100  years.  This was based on a hydraulic conduc-
tivity of 10    cm/sec, and would be an order-of-magnitude
less using an hydraulic conductivity of 10   cm/sec.  On
page 5-13 of the ECC RI, it is acknowledged that TCE will
experience some degradation if aerobic conditions exist, but
on page C-2-3 of Appendix C it is stated that rates of bio-
degradation are* difficult to estimate on a site-specific basis,
Giv«mftlMM considerations, the implied degradation time of
H) yeir» can b* considered to be the same .order-of-magnitude
as th^frfastest  travel-time estimate of 20 years.
     ' •*•' .",.
It should b« recognized that some volatile organic compounds
degrade into more conservative, toxic, or carcinogenic com-
pounds.  The more conservative degradation products would
travel faster to the surface water than the original organic
compounds.  An  example is TCE degrading to vinyl chloride.

Comment.  The estimated hydraulic conductivity of 10*  cm/sec
for the glacial till at MSL does not agree with other esti-
mates of the till hydraulic conductivity; specifically with
                              19

-------
estimates of 10   to 10   cm/sec by West  (cited in the NSL
FS, pages 1-11 and B-l).  It is not clear why the sand and
gravel water bearing unit of NSL has a lower limit of hydrau-
lic conductivity lower than that of the glacial till [sic]
 (Tricil).

U.S. EPA Response.  Measured hydraulic conductivity values
are presented in Table B-l in Appendix B of the NSL FS.  The
hydraulic conductivities presented in the table are for wells
which were screened across various lithologic units.  Most
of the test zones included some lenses or units of coarse
grained  soils other than clay or silt till.  Therefore, the
hydraulic conductivity values for till reported in the NSL
FS would be higher than values reported for samples consist-
ing completely of clay or silt till, as were the samples
tested By West.

The lowest hydraulic conductivity value reported in NSL FS
Table B-l is 5.8 x 10~3 cm/sec for well 11O (thefilow end of
the range).  This is a higher value than the 10   cm/sec
cited in the comment as the hydraulic conductivity of the
glacial  till.                                               *
                                                            $•
Comment.  No source is given for the effective porosity valt$*
of 0.10  used for glacial till (Tricil).                     $

U.S. EPA Response.  Davis and OeWiest (Hydrogeolqqy, John
Wiley &  Sons, 1966) state that most porosities of till fall
in the range of 25 to 45 percent (page 409).  Accepting this,
it is not unreasonable to assume that the effective porosity
of a very_denae (compact) glacial till would be on the order
of fO percent (0.10).

Comment.  No wells were installed upgradient and beyond the
influence of the landfill.  The absence of background data
makes it impossible to quantify the impact of the NSL site
(Tricil).

U.S. EPA Response.  It is true that there are no 'wells imme-
diately  upgradient of NSL and beyond the influence of the
landfill.  However, there are wells upgradient of the neigh-
bpria«r BCC sit* which are beyond the influence of the land-
fill.  Shallow well ECC 1A is located northwest of the BCC
site, and shallow well ECC-2A is located at the northeast
corner of BCC.  Sampling results from these wells may be
compared to> those from wells dovngradient of NSL.

Comment*  No attempt has been made to differentiate contami-
nants commonly found in municipal waste from those which are
solely attributable to the hazardous waste allegedly disposed
of in NSL.  The volumes of hazardous waste received by NSL
have been overestimated, and little or none of the hazardous
substances may remain in the landfill.  Drums have not been
                             20

-------
placed in NSL since 1983, and the 3 acre oil pond was removed
10 year* ago  [sic] .  There is no evidence that any intact
drums containing hazardous waste are buried in the landfill.
If drum* were disposed of, it is probable that they were rup-
tured by heavy equipment  (NSL, Inc.; Tricil) .

U.S. EPA Response .  The estimates of hazardous waste received
by NSL were the best available at the times of the RI's.  It
is true that no attempt was made to differentiate contaminants
from municipal and hazardous wastes.  It is likely that many
of the contaminants from hazardous waste would be similar in
type to those from municipal waste, which would make their
differentiation difficult.  Given the site-specific informa-
tion in the RI reports and in the comments, it is difficult
to determine if the 4 to 10 year period cited in the comment
is sufficient time for all contaminants from drums and the
oil pond to have moved out of the landfill.

Comment .  No indication is given as to how estimates of vola-
tile organic concentrations in groundwater at ECC, resulting
from the leaching of soil contaminants, compare to actual
measured values.  Methods used to estimate concentrations
should be presented (TRW, Inc.; Tricil).

U.S. EPA Response.  Estimated concentrations of volatile
organics in groundwater due to leaching from the unsaturated. .
soil are presented in ECC RI Table 5-5, and results of ground
water monitoring are presented in Table 4-13.  The estimated
average concentration of TCE due to leaching was 200,000 ug/1
TCE was detected in well 11A (completed in the shallow satu-
rated zone adjacent to the south boundary of ECC) at a con-
centration of 28,000 ug/1.  Other volatile organics for which
concentrations were estimated were not detected in well 11A.
The TCE concentration detected  in the well was 15 percent
of the estimated average concentration, but this may be due
to the location of the well along the site boundary rather
than in the middle of the site.  Methods used to estimate
concentrations are presented in Chapter 5 and Appendix C of
the ECC RI, and in Appendix A of the NSL FS.

          Oat* ia the remedial investigation reports do not
        any present substantial threat from groundwater con-
           at NSL  (other than in the immediate area of the
           nor do the reports show that the landfill has or
ever will" present a problem.  The landfill has been in exis-
tence- for 20 years, and it is not unreasonable to think that
substantial problems should have occurred already.  There is
no justification presented in the reports for the stated
expectation that contaminant levels would increase over time
to a maximum level, and that the time period before which
concentrations permanently decrease to nonhazardous levels
may be 100 years or longer.  The landfill may already be in
the stag* where the concentration levels are decreasing.  The
                             21

-------
nature and extent of the sources of contaminants within the
landfill are not well known, nor do the reports describe
reasonable mechanisms for future contaminant releases from
the landfill (NSL Committee; NSL, Inc.; Tricil; Chrysler).

U.S. EPA-Response.  Elevated levels of total dissolved solids
(TDS) were detected in groundwater monitoring wells screened
in sand units at the southwest corner of NSL, and in one well
near the southeast corner of NSL.  These elevated TDS levels
indicate that some leachate has migrated to the groundwater
from some portions of the landfill.  Also, organic contami-
nants were detected in some of the monitoring wells down-
gradient of NSL.  As these organic contaminants are not
expected to occur in ambient groundwater, their presence is
interpreted as an indication of contaminant release from NSL.
Refer to Tables A-7 and A-8 in Appendix A of the NSL RI for
details of contaminants detected in the monitoring wells.

Analyses.of surface water samples from the unnamed ditch
adjacent to the west boundary of NSL indicate the presence
of contaminants which may have been released from NSL.  If
these contaminants are from NSL, they would have entered tin
ditch via a surface water or groundwater pathway.  The pres<
ence of these contaminants in the ditch may be another indi-
cation of leachate migrating to the groundwater or surface
water from the landfill.

In the NSL FS (pages 2-3), it is stated that it is not possi-
ble to estimate future releases of contaminants from the land-
fill, and that it is possible that if contaminant types or
levels increase, the time period before which concentrations
permanently decrease to nonhazardous levels may be 100 years
or longer.  These statements were not meant to imply that con-
taminant types or levels in the groundwater will increase.
It is true that the nature and extent of contaminant sources
within the landfill are not completely known, nor have spe-
cific mechanism* been identified for future contaminant
releases.  It is for these reasons that increases in types
or concentrations of contaminants have been presented as pos-
sibilities.  Similarly, the time period of 100 years is only
presented a* a possibility and not as a projection.

Many tffct* collected over an extended period of time are'
needed to determine if contaminant release* from a landfill
are increasing or decreasing.  These type of data were not
available for.the NSL RX.  Since NSL remains an active site,
the possibilities for continued leachate generation and
increasing contaminant concentrations remain.

Comment.  The former cooling pond at ECC had been dredged and
the contaminated soil and sludge has been removed from the
pond.  Therefore, the cooling pond is no longer a source of
contamination.  The effects of its removal on contaminant
                             22

-------
migration were not evaluated.  The CAA report states that any
contaminated soil or sludge remaining in the cooling pond
would have to be excavated.  The need for this action is not
technically justified, and is an apparent discrepancy with
statements that contaminants have been removed from the pond
(ECC Steering- Committee; TRW, Inc.; Tricil) .

U.S. EPA Response.  It was reported in June 1985, in the
on-scene coordinator report for the immediate removal of ECC
by Roy F. West on, Inc., that the partially dredged pond was
backfilled with contaminated soil excavated from around the
process building and tank areas.  Therefore, the cooling pond
remains a potential source of groundwater contamination.  The
CAA report recommends that the pond area be investigated to
determine if it is contaminated, and to remove the contamina-
tion if .necessary.

Comment*  It is possible to distinguish between contaminants
from ECC at NSL both in terms of onsite and offsite contami-
nation. -The volumes of groundwater, levels and types of con-
taminants from ECC and NSL are different.  A greater propor-
tion of organic contamination is from the ECC site (ECC Steer-
ing Committee; NSL, Inc.).                                  I

U.S. EPA Response.  It is to be expected, based on what is  *
known about the contaminant sources at ECC and NSL, that
organics will constitute a relatively greater portion of the
contaminants from ECC than from NSL.  However, it is not
unreasonable to expect organic contamination to be released
from NSL.  Most of the landfill volume consists of refuse
and municipal waste, which has been observed to release orga-
nic '-contaminants to the environment at this and' other land-
fills.  There is also some additional volume of hazardous
substances within NSL, including the former oil separation
lagoon.

While differences in concentrations and types of organic and
inorganic contaminants from ECC and NSL may be distinguish-
able for portions of the sites, total contaminant mass con-
tribution* frost each site cannot be compared.  Estimates of
total groundwater discharge from each site are needed to cal-
culates contaminant mass contributions, and estimates of total
groundtimtar discharge were not generated as part of the.RI's
Or
Based OB this geology and hydrogeology of the NSL and ECC
sites, it is expected that groundwater contaminants detected
within the ECC site and adjacent to the south and west bound-
aries of the site are from ECC.  Similarly, it is expected
that groundwater contaminants detected along the south bound-
ary and at the southwest corner of the landfill are from NSL.
It is more difficult to distinguish the source of groundwater
contaminants found along the unnamed ditch, or of surface
                             23

-------
water contaminants  found  in unnamed ditch and in Finley
Creek downstream of its confluence with the ditch.

Comment.*  The shallow saturated zone  (till) beneath ECC is
not an aquifer, nor is the underlying sand and gravel lens.
The glac-ial- till unit beneath NSL does not constitute an
aquifer.  It is not reasonable to expect that drinking water
wells would be completed  in these formations, nor between
the sites and the groundwater discharge areas.  The justi-
fication for considering  these units as aquifers is not pre-
sented (ECC Steering Committee; NSL Steering Committee; TRW,
Inc.; Tricil).

U.S. EPA Response.  The publication entitled "Water Resources
of Boone County with Emphasis on Groundwater Availability
(W.J. Steen, et al., Department of Natural Resources, State
of Indiana, Division of Water, 1977) describes the area of
ECC and NSL as one  in which well yields from 5 to 150 gpm
can be developed.   It states that well supplies are predomi-
nantly obtained from sand and gravel aquifers within the
glacial drift at depths ranging from 30 to over 300 feet.
The intertill sand  and gravel aquifers are extensively used*

It is unlikely that the glacial till beneath NSL or the shaJ
low saturated zone  beneath ECC would be used for drinking
water due to their  low transmissivities and recharge poten-
tial.  An estimate  of well yield for the sand and gravel lens
beneath ECC is given in comments prepared by the ECC
Steering Committee.  They estimate a potential yield of
1 gpm (1,440 gpd) at a drawdown of approximately 2 feet below
the static groundwater level.  This would be sufficient yield
for"~a domestic water supply well.

Comment.  The extent of groundwater contaminants in the shal-
low saturated zone  (till) beneath ECC cannot be established
based on the one valid groundwater sample from that zone
(ECC Steering Committee).

U.S. EPA Response.  It is true that only one or two ground-
water Bonitoring""points existed in the shallow saturated
zone. ... Hovevejr, contamination of the shallow saturated zone
a* BCffvas assessed using data from the monitoring wells,
and a&o- from groundwater concentrations predicted using
result* from analyses of  soil samples collected from the
zone*  Details of the prediction methods are presented in
Chapter 5 and Appendix C  of the ECC RI, and in Appendix A of
the ECC FS.

Comment.  To estimate travel times of contaminants, a dis-
tance from monitoring wells to the surface waters was arbi-
trarily chosen as 50 feet.  If the distances between the
wells and surface waters  were increased, travel times may be
                             24

-------
long enough to allow implementation of remedial actions after
monitoring (NSL Steering Committee).

U.S. EPA Response.  The distance between the landfill perim-
eter and Finley Creek varies from approximately 10 to 200 feet,
based on:maps presented in the reports.  Therefore, a contami-
nant travel distance of 50 feet to the creek is a presently
existing condition of the site.  Contaminant travel times
would be increased if monitoring wells were further than
50 feet from the creek.  Increased separations between moni-
toring wells and surface water could be achieved by moving
the creek and/or the landfill perimeter.  However, the com-
ments do not establish that, even with increased separation,
there will be adequate time to react to increasing contami-
nant levels in monitoring wells.

Comment.  The possible reduction in leachate generation at
NSL is inadequate justification for a RCRA cap.  A reduction
in the quantity of leachate to be collected and treated would
not necessarily make an alternative with a RCRA cap more
reliable (Tricil; Ferro Corp.).
                                                            *
U.S. EPA Response.  Placing a RCRA cap on the landfill wouldh
decrease the rate of leachate generation, as compared to th«|
site with a soil cover, by the mere fact of reducing the    *
amount of percolation through the landfill surface.

In the CAA report (page 2-15) it is stated that operation and
maintenance of the treatment system in Alternative 5 (includ-
ing a RCRA cap) will be less than with Alternative 4 (without
a RCRA cap) because of the lower flowrate resulting from
decreased" leachate generation.

If an alternative including a RCRA cap is more reliable than
one without a RCRA cap, it is because a properly maintained
RCRA cap will be effective in almost eliminating leachate
generation, which will reduce the loading of contaminants to
the groundwater and ultimately to the collection and treat-
ment system.  In the CAA report, any comparisons of relia-
bility between Alternatives 4 and 5 on this basis were made
assuming; that Alternative 4 included a soil cover that pre-
vented- direct contact with the landfill surface, but did not
necessarily reduce the rate of leachate generation.

Comment.  The proposed groundwater monitoring system is unnec-
essarily complex considering the low levels of contamination
that occur today,  No additional wells are needed; the exist-
ing wells should be sufficient.  The monitoring program needs
careful review (NSL, Inc.; Tricil).

U.S. EPA Response.  The proposed groundwater monitoring pro-
gram for Alternative 5 in the CAA report is to assure that
the alternative is functioning properly and not necessarily
                             25

-------
to monitor trends in contaminant levels at the site.  There-
fore, the monitoring program was designed on the basis of the
anticipated response of the groundwater system to the
alternative and not on the basis of presently observed con-
taminant levels.

The conceptual design of the monitoring program will be
reviewed and revised as necessary during design efforts at
the site.  It will also be possible to modify the monitoring
program pending the outcome of the preliminary monitoring
results.  Modifications may involve either upgrading or down-
sizing the magnitude of the proposed monitoring program.

Comment .  The CAA report incorrectly concludes that insuffi-
cient time for implementation of remedial actions is avail-
able if major increases of contamination show up in the south-
west corner of the landfill.  Existing wells could be pumped
if contaminant levels increase, and additional wells could
be drilled on short notice if needed (NSL, Inc.).

U.S. EPA Response.  The comments provided no analyses of a
groundwater pumping system incorporating existing wells.
Therefore, this use of existing wells cannot be evaluated.
Pumping of existing wells to extract contaminated ground-
water is believed to be technically infeasible since these
wells were installed as monitoring wells for sampling pur- v-
poses and were not designed for long-term pumping use.

Comment.  The sand lens beneath the ECC site and the sand
and gravel zone along the unnamed ditch are distinctly dif-
ferent units.  The sand and gravel zone in the unnamed ditch
area begins at the ground surface and has a surface layer of
topsoil.  It is not overlain by glacial till as is the sand
lens beneath ECC.  The two sand units do intersect each other
(NSL, Inc.).

U.S. EPA Response.  Geologic cross sections in the NSL FS
(Figures 1-12 and 1-13) show that deposits of sand and gravel
do extend fro» Finley Creek and unnamed ditch to the south-
west co$ae)r of tb« NSL site and ECC.  The sand deposits are
shovtt*a* having different lithologies, which may be due to
            in origin (deposited immediately after glaciation
versi*!s*;x*cently as a result of stream action) .  However; the
fact fJBafcr the) sand units intersect each other supports the
interpretation in the CAA report that the sand and gravel
lens beneath the ECC site and the southwest corner of the
NSL site forma a -pathway for contaminated groundwater to
discharge directly to the creek.

Comment.  A groundwater interception rate of  60 gpm  from
beneath NSL is too high.  This is equivalent  to a 73 percent
infiltration of precipitation over the 70 acre landfill area
(NSL, Inc.).
                             26

-------
U.S. EPA Response.  Estimates of groundwater collection
rates are presented in Appendix B of the NSL FS.  The
estimated-rate of groundwater collection takes into consid-
eration the need to lower the water table at the collection
system to an elevation below that of Finley Creek.  By doing
this, the collection system rather than the creek will con-
stitute the area of groundwater discharge.

The comment assumes that the recharge area for groundwater
flow beneath NSL is limited to the area of the landfill.
The recharge area for this subregional groundwater flow sys-
tem may exceed the 70 acre landfill, in which case the equi-
valent infiltration would be less than 73 percent of pre-
cipitation.

An estimated groundwater collection rate of 60 gpm was used
for Alternative 5 in the CAA report.  This included the esti-
mates of flow to a groundwater collection system along the
south boundary of NSL, and of flow to a collection system
south and southwest of the ECC site in the area of the rela-
tively large sand and gravel lens.  The estimated flow to a
subsurface drain along the south boundary of the NSL site was
23 gpm (NSL FS, Appendix B, page B-ll).
Comment.  Calculations or references supporting the estimat
of leachate production at NSL are not provided.  The eati- v-
mates are too high for a landfill covered with a silty clay
till soil.  A rate of 40 gpm is excessive for annual pre-
cipitation of 38 inches on a landfill covered with clay and
having a sloping land surface.  Based on collection rates in
the__exis±ing leachate collection system, a high estimate for
leachate generation would be 1 gpm  (NSL Steering Committee;
NSL, Inc.).

U.S. EPA Response.  Estimates of leachate generation are pre-
sented in Appendix B of the NSL FS.  A percolation rate of
10 in/year was used for a soil cover on the landfill surface.
This does not represent an estimate of actual percolation
based on soil conditions, soil moisture balance modeling, or
records of leachate collection.  It was assumed that the pur-
pose of the soil cover was to prevent direct contact with the
landfill surface and not to reduce percolation.  Therefore,
it wa» not assumed that the cover, would necessarily consist
of silt; clay till soil.  If the soil cover did consist of
compacted silty clay till of sufficient thickness, it is
reasonable to expect that percolation would be less than
10 in/year.  It would also be reasonable to assume that the
percolation rate would be no larger than that rate which is
occurring now, if it could be adequately determined.

A percolation rate of 1.5 in/year was used for a RCRA cap on
the landfill surface.  This does not represent an estimate
                             27

-------
of actual percolation based on moisture balance modeling or
evaluations of RCRA cap performance.

Comment.  In 1982, the only well determined to be polluted
at NSL was MWl located near the southwest corner of the
landfill-.  -By 1983, the southwest corner of the landfill had
been removed and emergency response actions had been
undertaken at ECC.  Concentrations of both total organics
and chlorinated organics have decreased in MWl since 1983,
and these reductions have, for the most part, been
sustained.  Because refuse is no longer in contact with the
sand deposit at the southwest corner of MWl, the chloride
concentration in MWl will continue to decrease with time
(NSL, Inc.).

U.5. EPA Response.  The apparent reduction in concentrations
of organic and inorganic contaminants in MWl may be due to
the removal of the local source.  The refuse (source) was
dug up and reburied in the landfill further away from MWl.
The trends presented in the comments for organic and
inorganic parameters in MWl are conflicting, in that
inorganic concentrations increase as organic concentrations*
decrease.  It is possible that the data are insufficient tof
establish trends that could be used to predict future      |"
concentrations at MWl.                                     |

MWl may have been the only polluted well in 1982, but other
polluted wells were identified during the subsequent RI's.
The period of time over which MWl has been monitored is
short relative to the age of the landfill, and any trends of
decreasing concentration which may be established using data
from MWl would be characteristic of the southwest corner of
the landfill and not necessarily of the entire landfill
boundary.

Comment.  Contaminants in Finley Creek are from a source
other than ECC or NSL (ECC Steering Committee; Mersman).

U.S. EPA Response.  Information and field data collected
subsequent to tEe ECC and NSL remedial investigations
indieot* that iources of contamination may exist in areas
Xhicjtftaere not. specifically investigated during the RI's.
If ttpfc«« sources do in fact exist, they would contribute to
the OMfctapination observed in Finley Creek downstream of ECC
and N8£»  Bowever, sampling of Finley Creek, the unnamed
ditch, and monitoring wells adjacent to the creek and ditch
indicate that contaminants in the creek and ditch are being
contributed by ECC and/or NSL.

Comment.  The geology of the NSL site presented in the
remedial investigation report was reinterpreted in the
feasibility study.  The reinterpreted geology, which
included the identification of discontinuous lenses of sand
                             28

-------
and gravel within the till beneath the landfill, makes
migration of groundwater contaminants from NSL less likely
(NSL, Inc.-) .

U.S. EPA Response.  The geological interpretations presented
in the NSL RI were refined to include subsurface geological
information which became available during preparation of the
NSL FS.  The revised interpretation of the site geology
indicates lenses of water-bearing sand and gravel within the
glacial till beneath the landfill.  These lenses may occur
at or near the original ground surface beneath the refuse,
and may act as conduits for movement of groundwater and
contaminants from beneath the landfill.  The west boundary
of the landfill is above or near a relatively large lens of
sand and gravel which extends to the area occupied by Finley
Creek and the unnamed ditch.

Comment.  The method selected for calculating groundwater
contamination from NSL yields unrealistically high results
(as presented in column 2 of Table 2-4 in the CAA report).
The values for noncontaminated samples are discarded and do
not reduce the average as they should (NSL, Inc.).          *
                                                            £»
                                                            »•
U.S. EPA Response.  The average concentrations presented in *
the tables are averages of the samples in which the contami-*
nants were detected, and do not account for the samples in v-
which the contaminants were not detected.  The average of
detected contaminants were presented for conceptual treat-
ment plant sizing and costing purposes and not to completely
characterize groundwater contamination from NSL.

Comment.  The groundwater moving away from the landfill
proper should never be of poorer quality than leachate
[sic].  Minimal contamination was found in leachate liquids.
It is impossible for organic contaminant levels to increase
in the groundwater adjacent to the landfill without inputs
from ECC (NSL, Inc.; Tricil).

U.S. EPA Response.  It is true that, on a mass balance
basisr groundwater contaminated with leachate should have
low**, concentrations than the leachate due to its dilution
in grouadwater.  The dilution ratio will depend on the ratio
of leachat* generation to groundwater underflow.  No
leachcts! springs or seeps were sampled during the Rl's, but
samples were taken from the onsite leachate tanks, and from
ditches adjacent to the north and east sides of the
landfill.  It is reasonable to expect that leachate coming
out of the north and east sides of the landfill could enter
the ditches.

Samples from the leachate tanks and ditches were found to be
contaminated.  Summaries of the detected contaminants are
presented on pages 1-13 and 1-14 of the NSL FS.
                             29

-------
Comment.  Data are not presented to support the interpretation
that groundwater discharges to Finley Creek and the unnamed
ditch  (NSL, Inc.; TRW, Inc.).

U.S. EPA Response.  Interpretations of the site hydrogeology
are presented on pages 1-9 to 1-11 in the NSL FS.  Groundwater
levels in wells adjacent to Finley Creek and the unnamed ditch
were higher than the elevation of the adjacent surface water,
indicating an upward hydraulic gradient.  Flow occurs in the
creek and ditch during times of no-rainfall, which indicates
some degree of base flow groundwater discharge.  Seeps have
also been observed along the banks of the creek and ditch
during periods of low flow.  These data have been interpreted
to indicate that groundwater at the shallow and intermediate
depths investigated by the RI monitoring wells discharges to
the surface water.

Comment.  No information was presented to support the conten-
tion that the impermeable membrane to be installed in the
subsurface drain of CAA Alternative 5 is technically feasible.
CAA Alternative 4 is more likely to be technically feasible
since it substitutes wells for the subsurface drain (Jeffboat).
                                                           *
U.S. EPA Response.  Installation of the impermeable membranit-
is considered to be technically feasible.  Details of the  *
impermeable membrane proposed for the section of subsurface-
drain south of ECC and southwest of NSL are presented on
page 2-15 of the CAA report.  The membrane would be con-
structed in place as the drain trench was backfilled.  Syn-
thetic membrane would be placed along the trench wall, and
the clay_barrier would be constructed in layers by hand,
or By the placement of premanufactured clay panels.  Esti-
mated costs for construction of the membrane are presented
in Appendix A of the CAA report.

Comment.  The quantity of dewatering for CAA Alternative 4,
which includes wells in the sand and gravel unit south of
ECC and southwest of NSL, will be less than for CAA
Alternative 5, which includes a subsurface drain in this
area (Jeffboat).
              ..*v
fr.S. SPA Response.  It is true that the subsurface drain
will require more construction dewatering than the installa-
tion of walla.  The drain could, however, result in lower
long-term puaqping rates because of the opportunity to install
an impermeable membrane on the downgradient side of the trench,
and thereby minimize inflow from surface water.  The drain
will also allow the groundwater interception system to be con-
verted to a groundwater isolation system, as in CAA Alter-
native 6.  The advantages of this flexibility are discussed
in Chapter 2 of the CAA report.
                             30

-------
Comment.  In the CAA Alternative 5 groundwater collection
system, water will be pumped from a drain at a depth of
5 feet.below the existing water table.  This will not
eliminate the possibility of contaminated groundwater moving
under the drain and offsite.  The design depth of the pipe
should be carefully reviewed (Jeffboat; NSL, Inc.).

U.S. EPA Response.  The subsurface drain in the groundwater
collection system will be designed to lower the water level
to the point that contaminated groundwater flow into the
drain and not to the adjacent surface water.  Hydrologic
analyses conducted for the FS's indicate that lowering the
water table 5 feet may be sufficient to achieve this goal.
Groundwater may go beneath the drain, but. based on the
results of the RI's, this groundwater is not expected to be
contaminated.  Detailed calculations of drain geometry are
presented in Appendix B of the NSL FS.  The actual depth at
which the drain will be installed will be determined as part
of the design process for the alternative.

Comment.  A significant potential for dewatering problem*
moat likely would occur during construction of the groundwater
collection system.  Sloughing of sandy materials in the south-
west area of NSL and south of ECC could present significant?
problems.  No provisions.were made for managing the quantities
of dewatering (Jeffboat).

U.S. EPA Response.  Dewatering would be required during
construction of the subsurface drain, as would slope
stability of the trench walls.  Construction dewatering
would have to be handled and treated at either an onsite or
offsite facility.  Costs for excavation, shoring and
bracing, and dewatering were developed for alternatives in
both the NSL FS and CAA reports.  Refer to Tables 0-9 and
D-13 in Appendix 0 of the NSL FS, and to tables A-9 and A-13
in the CAA report.  No specific costs were developed for
handling and treatment of construction dewatering.

Design of lateral support systems for subsurface drains or
construction dewatering systems are not done as part of a
feasibility study.  Therefore, costs presented for these
system* in the FS and CAA reports are estimates only.
Estiafttes of construction dewatering will be developed as
part 6£ the design process for the alternative.

Comment.  A perimeter slurry wall should be proposed around
NSL so that the corrective action will be consistent with
requirements as determined in cause N-95 by the Indiana
Solid Waste Management Board on January 21, 1987.  The
slurry wall should not be rejected unless it can be clearly
shown that it will be ineffective.  The use of a slurry wall
should have been seriously considered by the FS and CAA
reports.  The assertion that the impermeable liner in the
                             31

-------
CAA Alternative 5 groundwater collection system would
minimize inflow from Finley Creek is inconsistent with the
reluctance to accept a slurry wall.  The sand and gravel
unit in the southwestern area of the landfill extends to a
depth of approximately 30 feet, and a slurry wall could be
placed to this depth in that area.  The likelihood of
groundwater movement across a slurry wall would be extremely
remote (Rock Island Refining; Jeffboat; Chrysler).

U.S. EPA Response.  The use of a slurry wall at NSL was
proposed on the basis of the site geology presented in the
NSL RI.  In this report, the site geology was described as
including a layer of sand underlain by glacial till.  The
purpose of a slurry wall would have been to block the flow
of groundwater in the sand unit to prevent it from
discharging to surface waters.  This would have been
achieved by placing the wall through the sand unit and into
the top of the underlying glacial till.  It is true that
there would be little groundwater movement through a slurry
wall/ so- that regional groundwater flow moving toward the
surface water discharge areas would tend to pile up behind
the slurry wall.  Some pumping of the upgradient side of thf
slurry wall would have been required to prevent the        -|.
groundwater from overtopping or flowing around the ends of | •
the slurry wall.                        .                   I

The interpretation of the NSL site geology was refined in
the NSL FS.  In this report/ the site geology was described
as including discontinuous lenses of sand and gravel within
the glacial till beneath the site.  The degree of hydraulic
interconnection between lenses at different locations and
different elevations is not known.  There is no identifiable
impermeable soil unit beneath all of the lenses into which
the bottom of a slurry wall can be placed/ and the
possibility remains for groundwater from beneath the
landfill to move beneath a slurry wall through a series of
interconnected lenses.

The impermeable liner in the CAA Alternative 5 groundwater
collection systea is not intended to prevent groundwater
discharges to surface water in the absence of the subsurface
djraio»  Pumping of water levels in the drain to an elevation
below; tn*t of the) creek will cause groundwater in the upper
portlOB of the water bearing unit to discharge to the drain
rather* than the creek.  The purpose of the impermeable
barrier on the downgradient side of the drain trench is
simply to minimize inflow from the creek.  It is anticipated
that some surface water will move beneath the barrier and
into the subsurface drain*

Alternative 5 in the CAA report includes an impermeable
barrier on the downgradient side of the subsurface drain
trench in the area of the relatively large sand and gravel
                             32

-------
lens southwest of the landfill and south of ECC.  This
barrier will extend into the glacial till beneath the sand
lens, and-for this reason will essentially act as a slurry
wall..  The need for groundwater pumping on the upgradient
side of the,, barrier to prevent groundwater from overtopping
or moving around the barrier will be achieved as the
subsurface drain is operated to collect contaminated
groundwater.

Comment.  A cap on NSL consisting of compacted glacial till
soils which surround (and underlie) the site would meet RCRA
cap requirements with respect to percolation of incident
precipitation.  A compacted till cap would substantially
reduce the quantity of leachate generation, and there would
be no significant degree of difference in the potential for
the migration of contaminants to groundwater between this
cap and a soil-synthetic membrane-clay cap.  The failure to
consider glacial till as a capping material is a major
omission.in the analyses (NSL Steering Committee; Tricil).

U.S. EPA Response.  The soil cap proposed in the reports was
intended to prevent contact with surface soils, and not     *
necessarily to reduce percolation rates.  It is true that a~-
cap of compacted native glacial till could significantly    \
reduce percolation through the landfill and thereby reduce  :
generation of leachate.  Local soils would have to be
investigated to determine if they are adequate for use as a
cap.  It would take some time for the reduction in
percolation to manifest itself as reduced leachate
generation; in the reports this was assumed to be 5 years.

Percolation through a soil-synthetic membrane-clay (S-SM-C)
cap would be less than through a compacted till cap, if the
synthetic membrane was properly installed and remained
intact.  While percolation rates through both types of caps
may be small, the rate through a compacted till cap may
still be twice or more of that through a S-SM-C cap.  This
would result in twice or more as much leachate to collect
and treat.  However, it is reasonable to expect that the
difference ia percolation through a S-SM-C cap and a
properly designed and installed compacted till cap would be
sttal£with respect to estimated total groundwater flowrates
to th* proposed groundwater collection system.

Consent.  The principal reference for alternatives in the
CAA report was the NSL FS.  The discussions in the CAA
report on groundwater collection, cap technology, and
groundwater treatment differ significantly from those
presented in the ECC FS (ECC Steering Committee).

U.S. EPA Response.  Many aspects of the alternatives
presented in the CAA report are similar to those in the NSL
FS.  The 6-acre ECC site is small compared to the 70-acre
                             33

-------
NSL site,  so  that when  the  sites  are  combined,  as  they were
for the CAA report,  remedial  actions  addressing the NSL  site
dominate those  for the  ECC  site.  For example,  only small
modifications would  have  to be made to a groundwater
collection system around  NSL  to include the ECC site.
Certain-technologies proposed in  the  ECC FS were not
presented  in  the CAA report because while applicable to  ECC,
they are not  reasonable to  apply  to the combined sites.  An
example is removal of contamination in the near surface
soils at ECC, which  could continue to be a source  of
groundwater contamination.  This  technology was not
presented  in  the CAA report.  If  it had been, similar types
of  source  removals would  had  to have  been proposed for NSL.
These could have included removal of  residues from the
former  oil pond.

Comment.   Groundwater extraction  wells are not  appropriate
for consideration to remove contaminated groundwater from
the sand and  gravel  aquifer beneath ECC  (ECC Steering
Committee).

U.S.  EPA Response.   A subsurface  drain rather than wells is*
included in the proposed  CAA  Alternative 5.  The purpose off.
groundwater collection  from the sand  and gravel unit beneatar
ECC is  to  prevent migration of contaminated groundwater  to  \
surface water.  Groundwater in the unit was found  during the
remedial investigations to  be contaminated, and based on
observed groundwater levels it is expected that the
groundwater discharges  to the unnamed ditch and/or Finley
Creek.  Contaminated sludge and soil  was removed from the
ECC cooling pond during initial remedial actions,  but the on
scene coordinators report for that activity  (by Roy F.
Weston, Inc., June 1985)  states that  the pond was  backfilled
with contaminated soil  from the ECC site.  The  pond may,
therefore,  continue  to  be a source of contamination for  the
sand and gravel unit.

Comment.   Assumptions of  no dilution  of groundwater as it
enters  Finley Creek  is  very conservative.  Neglected is  the
fact that  when  the creek  is under low flow conditions and
groundwater contributions stop, it is likely that  leachate
fj.ow weald also stop.   No calculations are given to support
the> factors given on page 6-48 of- the NSL RI for dilution of
volatile organic compounds  in groundwater after discharge to
surface water (NSL,  Inc.; Tricil).

U.S.  EPA Response.   It  is true that,  as flow in the creek
decreases  as  a  result of  decreasing groundwater discharge,
.the discharge to the creek  of contaminants in groundwater
will also  decrease.  However, it  is not unreasonable to
anticipate that the  rate  of leachate  generation would remain
relatively constant  since it  is a result of average
long-term  percolation of  water through the landfill surface.
                              34

-------
Therefore, under these conditions it would be expected that
leachate would constitute a greater proportion of discharge
to the creek than under high flow conditions.

Dilution factors presented on page 6-48 of the NSL RI are
based on:the discussions of groundwater and surface water
flow on pages 5-11 through 5-13 of the NSL RI.

Comment.  The degree of accuracy of hydraulic conductivity
estimates made from grain size analyses of the sand unit
beneath ECC is not given.  No data are available to indicate
that the hydraulic conductivity is as high as 10   cm/sec,
nor to indicate that the unit is homogenous and isotropic in
this regard.  Estimates of 10   to 10   cm/sec were made for
the sands beneath NSL  (Tricil).
                                 -2      -3
U.S. EPA Response.  A range oflO   to 10   cm/sec was given
for the hydraulic conductivity of the sand and gravel unit
beneath ECC (ECC RI, page 4-42).  Grain size distributions
of soil samples collected at ECC are presented in Appendix D
of the Technical Memorandum for Subtask 3-1, all in
Appendix A of the ECC RI.                                  ,
                                                           y
Hydraulic conductivities at NSL were estimated from slug   ?
tests in monitoring wells.  Results of these tests are      :
presented in Table B-l of NSL PS,Appendix B.  The test zones
yielding estimated values of 10*  to 10~  cm/sec usually
included units of clay or silt till, silty fine sand, or
fill along with clean sand and gravel.  The grain size
analyses used to estimate hydraulic conductivity of the sand
beneath ECC were of samples consisting of clean, sand without
lenses o1f~finer grained soils.

Comment.  Minor upgrading of the existing glacial till cap
at NSL would result in a cap with an effectiveness, relative
to percolation, equal to that of a so called RCRA cap
(Tricil).

U.S. EPA Response.  It is true that a cap of compacted
glacial till coold significantly reduce percolation through
the landfill surface.  Percolation through a RCRA cap would
b« less; than through a compacted till cap, if the synthetic
membrane in the RCRA cap was properly installed and remained
intact, but it is reasonable to expect that the difference
in the percolation rates would be small.  The degree to
which the existing glacial till "cap" on the landfill would
have to be upgraded to be as effective as a RCRA cap was
unknown at the time of the FS's, and remains unknown.

Comment.  The rates of groundwater movement beneath NSL have
never been determined.  Rates presented in the reports
appear to be high.  Calculations are not presented in the
reports (TRW, Inc.; Tricil).
                             35

-------
U.S. EPA Response.  Rate of groundwater movement beneath the
NSL site is discussed on pages B-20 and B-21 of Appendix B
of the NSL FS.  Difficulties of estimating movement rates
beneath NSL are discussed therein.  Estimates of groundwater
velocities beneath NSL were generated, but were not
presented in -the report because of the difficulties involved
in making such estimates.  These estimates were provided to
interested parties who made a FOIA request.

Comment.  No estimate is given of the volume of contaminated
sediment [sic] which remains at the ECC site.  Therefore,
potential future harm cannot be adequately addressed  (TRW,
Inc.).

U.S. EPA Response.  On page A-l of Appendix A of the ECC FS,
it is stated that "an estimated 11,300 cubic yards of soil
with contaminant concentrations having a calculated excess
lifetime risk of 10   or greater for residents ingesting
soil" would need to be excavated from ECC.  Estimates of
volumetric weighted average soil concentrations used in the
analysis of groundwater leachate interactions at ECC are
presented on page 1 of Attachment 2 of Appendix A of the ECQ
FS.                                                         I
                                                            »'
Comment.  Migration of contaminants to the nearest          I
residential wells was not indicated by the RI data.
Therefore, residential wells are not threatened by ECC (TRW,
Inc.).

U.S. EPA Response.  The deep confined aquifer below the ECC
site was not found to be contaainated during the RI, and
future migration of contaminants to this aquifer is highly
unlikely due to the upward vertical hydraulic gradient.
Therefore, it was not unexpected that residential walls
completed in the deep confined aquifer were not
contaminated.  It is expected that migration of contaminants
in groundwater will be limited to shallow sand and gravel
units (ECC RI, page 5-5).

Comment.  No estimate is given for the volume of groundwater
discbicging to surface water from ECC, nor as to whether the
«f feets of tn« clay surface on groundwater discharge was
con«£4*red (Tricil).             .         .
     •«•••->'
U.S. BP» Response.  Details of groundwater discharge
estimates from ECC are presented in Chapter 5 and Appendix C
of the BCC RI, and in Appendix A of the ECC FS.  It is
stated on page 2 of Attachment 2 of Appendix A in the ECC FS
that estimations of recharge at ECC were made assuming that
no cap was present.

Comment.  The clay soils placed on the ECC site during the
initial remedial actions will discourage leaching of soil
                             36

-------
contaminants and migration to groundwater.  The effect of
the clay layer on the leaching of soil contaminants to
groundwater was not considered by the RI's or FS's, nor was
it taken into account in the estimates of groundwater and
surface water concentrations resulting from leaching.  In
Appendix-A-of the ECC, it is assumed that no cap exists on
the ECC site and that the recharge rate is 7.8 in/yr.  A
more reasonable rate of recharge through the clay soils
would be 0.1 in/yr (TRW, Inc.; Tricil).

U.S. EPA Response.  It is true that clay soils were placed
over the ECC site as part of the initial remedial action,
but how well this material would act as a "cap" has never
been evaluated and is therefore unknown.  For this reason,
soil contaminant leaching at ECC was evaluated as if the
clay soils did not exist.

If the clay soils do act to some degree as a "cap," the
recharge of 7.8 in/year could be unreasonably high.  But
0.1 in/year seems unreasonably low for any kind of clay
soils which could be present on the ECC surface.  If the
hydraulic conductivity of any clay soils on the ECC site
were in the range of 10   to 10   cm/sec, then recharge    *:
would range from as much as 12 to 1.2 in/year, depending on»"
the degree of saturation of the surface soils.             *

Comment.  It is impossible to evaluate the accuracy of the
contaminant transport and fate calculations without details
of the model used.  The factors applied to conclude that
there were certain mobilities and persistence of
contaminants need to be clarified.  The wide range of
variations of transport and fate properties of indicator
chemicals make assessments of future conditions to appear as
no more than a guess (TRW, Inc.; Tricil).

U.S. EPA Response.  Contaminant fate and migration at NSL is
discussed in Chapter 5 of the NSL RI, and summaries of
environmental behavior of indicator organic compounds and
metals are presented in Table 5-3 and 5-4, respectively.
Environmental profiles of contaminants at NSL are presented
in Appendix B of the NSL FS.  Similarly, contaminant fate
and migration at ECC is discussed in Chapter 5 of the ECC
rfl, environmental behavior of indicator chemicals are  •
summarized in Table 5-4, and discussions of contaminant
transport and fate are presented in Appendix C.

The ranges of travel times for contaminants at ECC, shown on
page 5-13 of the ECC RI, are due to ranges in values for
soil properties, hydraulic conductivities, and travel
distances.  Details.of these travel time calculations are
presented in Chapter 5 and Appendix C of the ECC RI.
                             37

-------
Comment.  Values of hydraulic conductivity for ECC would be
erroneously high, as would estimated rates of groundwater
movement, if corrections in the analyses were not made to
account for the sand pack around the monitoring well screens
 (Tricil).

U.S. EPA" Response.  Estimates of hydraulic conductivity for
ECC were made from grain size analyses and not from well
tests.  Therefore, corrections for the sand packs were not
needed.

Comment.  It is not clear in CAA Alternative 4 if the flow
of 140 gpm is from ECC alone or from ECC and NSL combined.
A combined flow of 140 gpm would not be needed [sic] if soil
contaminants at ECC, which would leach to groundwater, were
removed:and treated (Mersman).

U.S. EPA Response.  The estimated flows for CAA
Alternative 4 are broken down on page 2-13 of the CAA
report. • The ECC underdrain would contribute an estimated
8 gpm, the subsurface drain around NSL would contribute
25 gpm, and the six extraction wells south of ECC and
southwest of NSL would contribute 65 gpm.  The leachate    *
collection system around NSL would contribute 40 gpm.      i~

The ECC underdrains in Alternative 4 could be eliminated if..
soil contaminants were removed.  If, however, the ECC
underdrains were eliminated, the flow to the subsurface
drains, extraction wells, and leachate collection system
would be reduced by only 8 gpm.  Page C-l of appendix C of
the__CAA .report states that the groundwater collection system
for CAA Alternative 4 would be similar to that for
Alternative 4 in the NSL PS, as would the flowrates.

Comment.  The contamination in the shallow sand and gravel
below ECC has not been fully attributed to any hazardous
waste disposal at the surface level.  Contamination was from
the cooling pond.  The evidence with regards to any
contaminants at the ECC site below a mere shallow
contaminated zone is not at this time attributable to any
contaminant* is that shallow zone [sic]  (Mersman).

U.S. BPA Response.  On page 4-59 of the ECC RI, it is stated
that, contamination of the shallow sand and gravel unit
beneath: ECC stay have occurred either via migration through
the silty clay till onsite or through contaminated water and
sediment in the former cooling water pond, which intersected
the shallow sand and gravel unit.

It is true that hydraulic gradients from the unit are now
vertically upward, so that downward migration of surface
contaminants would not be expected in the future.  But it is
not known if past activities at ECC could in fact have
                             38

-------
caused a reversal of this gradient and allowed downward
migration of contaminants.

Comment.  "No information is given regarding the drilling
contamination problems at ECC well 4A.  It is questionable
if drilling..contamination could have occurred at other wells
(Tricil) .-

U.S. EPA Response.  The drilling of ECC well 4A is discussed
on page 4 of the Hydrogeologic Study Technical Memorandum in
Appendix A of the ECC RI.  Drilling problems similar to
those at well 4A would have been described if they had
occurred.

Comment.  There is no evidence presented to confirm the
suggestion in the NSL RI that the water table within the
landfill is mounded (Tricil).

U.S. EPA Response.  Interpretations of mounding within the
landfill .were modified for the NSL FS.  On page 1-11 of the
NSL FS, it is stated that the groundwater in the glacial
till beneath the landfill may be mounded, but that there
could only be localized contact between groundwater and the-?
landfill refuse.  Detailed discussions of mounding are in   |"
Appendix B of the NSL FS.                                   f

Comment.  The benefit of a leachate collection system more
than 1 mile in length cannot be considered to be
cost-effective for the collection of the 5 gpm of leachate
expected to be produced after NSL is capped (Tricil).

U.Sr- EPA-Reaponae.  A leachate generation rate of 5 gpm is
equivalent to approximately 7,000 gallons of leachate
generation per day, and 2,600,000 gallons over the course of
a year.  If this leachate is not collected, it will enter
groundwater or surface water adjacent to the site.

Comment.  There is no evidence that the sand and gravel unit
beneath ECC is a discrete water bearing unit and does not in
fact occur as discontinuous lenses [sic] (Tricil).

0.3. PA Response.  Geologic cross sections through the ECC
sit* are shown in Figures 1-12 and 1-13 in the NSL FS.  .The
continuity of the sand and gravel unit was interpreted on
the b«*is> of the thickness of the unit encountered in the
test boring*, and the relative location* of the borings in
which the unit was encountered.  On page 1-4 of the CAA
report, it is stated that because the thickness and
continuity of the lens beneath ECC is greater than other
sand and gravel lenses encountered in the test borings, this
lens has been considered as a discrete unit within the
glacial till.
                             39

-------
Comment.  The effect of temperature/ soil organic content,
and oxidation reduction potential on reducing contaminant
levels at.NSL were not assessed  (Tricil).

U.S. SPA Response*  The specific contents of the landfill
are unknown:;  Much information exists on generation and
migration of leachate (for example, in J.C.S. Lu, et al.,
Leachate from Municipal Landfills, Noyes Publications,
1985) , but it would be difficult to quantify the effects of
physical-chemical features of the site on generation and
migration of leachate without a more thorough knowledge of
the nature and extent of municipal and hazardous wastes
within the landfill.

Comment.  The increase in contaminant concentrations at NSL
(if it ever occurs)  is expected to be very gradual.  A
monitoring system could be carefully developed to measure
groundwater quality close to the landfill which would detect
any significant increase in contaminants, should that occur.
The concern about insufficient time to implement remedial
actions once previously undetected contaminants or increased
levels of contaminants are detected has no basis and is     -t
highly questionable due to the slow rate of groundwater     v-
movement.  A much larger span of time will be made available)
by observing a correlation of groundwater contaminant       i
increase with time.   An upward or downward trend would be  -
gradual with respect to contaminant levels, and there would
in fact be sufficient- time for the implementation of
remedial measures.  An additional safety factor is provided
by the low contaminant levels described in the reports.  A
considerable increase would, therefore, be necessary for an
increase in risk.  If levels of contamination are found
through monitoring to be rising, the additional action could
be implemented (NSL Steering Committee; NSL, Inc.; Tricil;
Chrysler; Ferro Corp.).

U.S. EPA Response.  Calculations of estimated groundwater
velocities in sand and gravel lenses at NSL were provided in
response to various FOIA requests.  The estimated velocities
ranged from approximately 0.2 to 17 feet/day.  Differences
in the> estimate* were due to variations in estimated
hydraulic conductivity values, in measured hydraulic
gradientsf and in assumed values of effective porosity.•
Contaminant velocities would be less than the groundwater
velocity, depending on the retardation factor of the
contaminant*  For some of the indicator contaminants at NSL,
these factors ranged from 1.1 to 2.4.

The range of estimated velocities indicates the degree of
uncertainty that would be inherent in designing a
groundwater monitoring program that would allow enough time
to react to increasing contaminant levels in groundwater.
An adequate monitoring program would have sufficient
                             40

-------
distance, between the point of monitoring and surface water
to allow enough time to react to increasing contaminant
levels.  At certain locations along the site perimeter,
sufficient distance may only be obtainable by moving surface
water-courses and/or the landfill perimeter itself.  It
would also have to be assured that no sources of
contamination exist between the line of monitoring points
and the surface water.  It may be technically infeasible to
develop sufficient distance between monitoring points and
surface water, and the cost of doing so may be high compared
to the cost of implementing CAA Alternative 5.  CERCLA does
not permit U.S. EPA to implement an alternative which allows
offsite migration of contaminants.

Comment.  The conclusion that groundwater monitoring will
not allow sufficient time to implement remedial action is
unjustified for the ECC site.  Travel times from the site to
the unnamed ditch vary between 20 and 800 years, and the ECC
RI states that most of the volatile compounds will degrade
to below.the 10~  cancer risk level within 10 years (pages 5
to 11).  For the foreseeable future, contaminated
groundwater would have no impact on surface water, and
monitoring would suffice as protection (ECC Steering        £
Committee; TRW, Inc.).                                      f

U.S. EPA Response.  A difficulty with monitoring at the ECCJ*
site is the relative proximity of the eastern boundary of
the site to the unnamed ditch.  Once contaminants were
detected in monitoring wells adjacent to the east boundary
of the site, only short travel distances would be needed to
reach the_ditch.  While contaminant transport rates in the
shallow saturated zone may be slow, they may still be fast
enough to travel the distances to the ditch before remedial
actions can be undertaken.  A groundwater velocity of
2.6 feet/year was estimated for the shallow saturated zone
(till) beneath ECC, and of 100 to 1,000 feet/year for the
underlying sand and gravel unit (ECC RI, pages 5-8 to 5-11).

4.9  TECHNOLOGIES AND COSTING METHODS

Capping-
      . ^ •
Coninwfct.  EPA's recommendation to place a soil-synthetic
membr9M*»clay cap over both ECC and NSL is unwarranted


     o    Zt offers no significant benefit over a soil-clay
          cap

     o    It is technically infeasible

     o    A simpler, less expensive cap could be used and
          still meet RCRA requirements
                             41

-------
 (ECC Steering Committee; NSL Steering Committee; Jeffboat;
 Rock Island Refining; Tricil; Jones, Inc.; Thermoset; Ferro
 Corp.; Mersman).

 U.S. EPA Response.  The selected alternative must comply
 with all-applicable/ relevant and appropriate requirements.
 Since ECC and NSL had interim status under RCRA, both sites
 must be capped with a RCRA compliant cap.  (Please refer to
 the Record of Decision  (ROD).)  The soil-synthetic
 membrane-clay cap meets the RCRA requirements and is
 technically feasible to implement.  During design the cap
 ultimately used at the site may be refined to reduce costs.
 However/ it would still need to meet the RCRA requirements
 to minimize liquid migration and maintenance/ promote
 drainage/ accommodate subsidence/ and have a permeability
 less than or equal to any bottom liner or natural subsoils.

 EPA has invited the PRP's to develop an alternate cap design
 that is in compliance with RCRA.

 Comment.  The soil-synthetic membrane-clay cap presented in
 the FS's and CAA would not be as effective as a glacial till
 cap since it is subject to ripping or cracking from        I
 differential settlement (Tricil).                          |"

 U.S. EPA Response.  The soil-synthetic membrane-clay cap
 proposed in the FS's and CAA would be more effective than a
 glacial till cap because it incorporates the flexibility of
 the membrane and the "self-healing* capabilities of clay.
 If differential settlement of the landfill over time was
 sufficient to cause ripping or cracking of the membrane/ the
 cap'would still be more effective than a glacial till cap
 due to the clay layer.  However/ the amount of differential
 settlement necessary to rip a membrane would typically
 create a noticeable disjunction at the landfill surface.

 The caps presented in the FS's and CAA are conceptual and
 are used to present a range of cost and reliability.  The
 final design of the cap for the site will need to consider
 the possibility of damage to the membrane from differential
 settlement and the cost and complexity of repairs.

 Comment*  Ths> recommendations for. a soil-synthetic
membrane-clay cap on the ECC site is unwarranted since the
 effectiveness of the existing clay cap and concrete pad have
 not been evaluated (Tricil; ECC Steering Committee).

 P.S. EPA Response.  The integrity of the existing cap is in
 question because water samples taken from the ponded surface
water were found to be contaminated.  The contamination may
 have occurred from upward migration of VOC's from the
 underlying contaminated soils or from mixing of cover
material with underlying soil.  The concrete pad on the
                             42

-------
southwestern portion of the site is not an adequate cap over
the long-term because it is subject to cracking from freeze/
thaw conditions.

Comment.  Placing a cap over the ECC site would be counter
productive since it would eliminate volatilization which is
one of the major transport routes for contaminants.  If a
cap were placed over the area, this route would be blocked
and the only transport would be via groundwater (NSL, Inc.).

U.S. EPA Response.  The intent of capping the ECC site is to
eliminate direct contact with contaminants and to minimize
the mobility of the contaminants by reducing infiltration
and volatilization and preventing transport via surface
runoff. . The release of contaminants to surface water or the
air could pose additional threats to public health.

Comment.  What is U.S. EPA's previous experience with soil
caps versus soil-synthetic membrane-clay caps and is the
latter worth the extra $13 million?  (NSL Steering
Committee; NSL/ECC Public Hearing December 17, 1986).

U.S. EPA Response.  No data is available for a side-by-sidel*
comparison of the performance of soil caps and              I
soil-synthetic membrane-clay caps over time.  A soil cap is-
used to eliminate direct contact with contaminated soil or --
debris and to enhance the growth of vegetation for erosion
control and increased evapotranspiration.  A soil-synthetic
membrane-clay cap performs these functions and, in addition,
minimizes infiltration into the landfill.  The benefit is a
reduction_in the quantity of leachate that is migrating to
the "groundwater.  Theoretically, this will result in cost
savings by reducing the time period over which the leachate
and groundwater need to be collected and treated.

Comment.  The relocation of the unnamed ditch is unwarranted
and inappropriate for the ECC site (ECC Steering Committee).

U.S. EPA Response.  EPA considers ECC and NSL to be one site
(see cocnent* on- COMBINATION OF SITES).  The unnamed ditch
wa« rerouted to the western side of the ECC site to allow
placement of a continuous cap across the combined site, and
to mittiaize the length of the collection system and
grouatfvater monitoring system.

Cooling Pond Sludge

Comment.  Removal of the soil (sludge)  from the bottom of
the former cooling pond is unwarranted since the pond was
previously dredged and no data exists to indicate that the
existing soil is contaminated.  The removal of this material
would provide only minimal benefit to groundwater protection
(ECC Steering Committee; Tricil).
                             43

-------
U.S. EPA Response.  During removal of the contaminated
sludge from the cooling pond, significant dewatering
problems were encountered and all the contaminated sludge
may not have been removed.  As a result, the cooling pond is
still* a- potential source of contamination.  The selected
alternative-included further investigation of the pond
contents'and removal, if necessary.  In response to comments
and further evaluation U.S. EPA believes that even if the
pond contents are contaminated, removal would provide
minimal benefit since offsite migration of contaminants
would be prevented by the cap and the groundwater collection
and treatment system included in the recommended
alternative.

Groundwater Treatment

Comments.  No data were presented to substantiate that there
is sufficient BOD or biodegradable COD in the leachate and
groundwater to sustain a biological treatment system (NSL
Steering-Committee).

U.S. EPA Response.  As mentioned in the NSL-PS and the CAA,...
the treatment system was developed with only limited data.  1.
Pilot studies and additional sampling are necessary to      |
determine if the proposed treatment system is the most      $
cost-effective system.  The powdered activated carbon
treatment (PACT) system was chosen for the purpose of cost
estimating because it is a viable alternative and it offers
a large degree of flexibility.  The PACT system has been
shown to operate effectively with influent BOD and COD
concentrations as low as 50 mg/1 and 100 mg/1, respectively
(Zimpro Tnc. Technical Bulletin).  Historical data from the
monitoring wells at NSL indicated a range of COD
concentrations from 1 mg/1 to 300 mg/1.  The COD
concentrations in the leachate are expected to be much
higher based on typical concentrations reported in municipal
landfill leachate .  Additional data and testing are
necessary to define the characteristics of the leachate and
groundwater before a treatment system can be designed.

Conaent.  Th« groundwater treatment system selected for the
ECC site is inconsistent with the system selected for both
si test; (BCC Steering Committee).           •

U.S. BPA Response.  The CAA states that additional sampling
and pilot studies are necessary to determine the most
cost-effective treatment system for the leachate and
groundwater from the combined sites.  The system selected in
 Tchobanoglous, Theisen, and Eliassen Solid Wastes.  New
 York:  McGraw-Hill, Inc., 1977.  p.
                             44

-------
the ECC-FS for ECC site alone would not be appropriate for
the contained sites because the leachate from NSL is expected
to have a. much higher BOD with a significant portion in the
form of nonhazardous organic matter.  Since activated carbon
will hot preferentially remove the hazardous organics, the
organic .-matter will quickly saturate the carbon bed
necessitating frequent replacement and resulting in high
operational costs.  As mentioned in the NSL-FS, the organic
matter must be treated prior to activated carbon adsorption.
The NSL-FS presented two treatment options— biological
treatment followed by activated carbon adsorption and
activated carbon enhanced biological treatment (PACT) .

In addition, the NSL-FS and CAA proposed a precipitation
system be added to the treatment facility for removal of
metals detected in the leachate from NSL.

Comment .  The concentrations of heavy metals are too low for
effective removal by chemical precipitation (NSL Steering
Committee) .
U.S. EPA Response.  The NSL-FS and CAA state that pilot
bench- scale testing are necessary to refine the treatment   i.
system.  Additional sampling must be performed to better    i~
define the heavy metal concentrations in .the groundwater andt
leachate.  Pilot and bench-scale testing will then determine
which system is the most cost-effective for meeting the
discharge limits.  The chemical precipitation was selected
for cost estimating purposes and is a viable alternative.

Comment .  EPA has not addressed adverse health impacts
associated" with the use of carbon adsorption.  Contaminants
will be removed from the surface or groundwater only to be
released to the environment elsewhere.  Carbon adsorption
could even pollute the wastewaters being treated.  The
presence of metals and other potentially toxic materials in
carbon, particularly regenerated carbon, may pollute the
treated waters (Jef fboat and Rock Island Refining) .

U.S. EPA Response.  Activated carbon adsorption is a well
established tecfinblogy widely used throughout the world for
treatment of drinking water as well as wastewater.  The
comment that carbon may actually pollute the water being
treate* ia unsubstantiated.  More specific information is
necessary to better address this comment.
The system proposed in the FS's and CAA would use new or
"virgin" carbon.  The saturated or "spent* carbon would be
incinerated or disposed of properly in a RCRA landfill.

Comment.  The treatment system proposed would not be capable
of treating and reducing chloride, total dissolved solids,
sodium, or other similar components found in landfill
leachate (Jeffboat and Rock Island Refining).
                             45

-------
U.S. EPA Response.  Although the proposed treatment system
is not specifically designed for removal of these
constituents, some reduction is expected to occur.  The
discharge-limits for the conventional pollutants and
hazardous substances will be established in the NPOES
permit.  If additional treatment processes are necessary to
reduce chloride, total dissolved solids, sodium or other
constituents, they will be included in the final design.

Comment.  The proposed groundwater treatment system is not
currently needed based on the statement in the CAA that
"failure of the... treatment system is not likely to pose a
risk to public health or environment over the short-term at
present contaminant levels" (Chrysler).

U.S. EPA Response.  At the current contaminant levels, the
risk to'public health or environment is based on long-term
exposure.  Failure of the treatment system for a short period
of time would not pose additional risk.  If concentrations
increase/ then even short-term exposure may increase the risk
to public health or the environment (see comments under
Endangerment Assessment for further information).

Comment.  The ultra-conservative approach to various       »*
elements of design is additive yielding an unnecessarily   |
expensive design (NSL, Inc.).

U.S. EPA Response.  The combination of total flows and
loadings which could occur were used for conceptual design
purposes.  EPA recognizes the proposed treatment system is
based on conservative assumptions.  Additional sampling and
pilot and-bench-scale testing will be performed to better
define the wastewater characteristics and to develop the
most cost-effective treatment system.

Comment.  EPA failed to consider energy consumption in their
analysis of alternatives, i.e., pumping costs for
groundwater collection and use of coal for activated carbon
(Jeffboat and Rock Island Refining).

U.S. SPA Response.  Neither the amount of energy consumption
nor tftfe utilization of resources is of such a magnitude as
to diltiooat any of the alternatives.
     •*!-   ^ '                        '
Coiuiientk  EPA has not provided for the treatment of water
from construction of the groundwater collection trench.
Offsite transport of this waster for treatment would
substantially increase the cost of (CAA) Alternative 5
(Jeffboat).

U.S. EPA Response.  The quantity of water requiring storage
and treatment from dewatering during construction will be
                             46

-------
estimated during the predesign phase.  The onaite treatment
system will be designed and installed to handle this water.

Comment.  EPA has not considered the impact on the schedule
for completing the corrective action if it were required to
install' the' wastewater treatment system for use in treating
waters resulting from dewatering during the installation of
the groundwater interceptions system (Jeffboat).

U.S. EPA Response.  The schedule for completing the corrective
action will be developed in the predesign phase.  Storage and
treatment of the water from dewatering will be taken into
account.  It is not expected to take any longer then the
installation of the cap and the groundwater collection system.

POTW Treatment

Comment.  The exclusion of POTW treatment based on
uncertainty of operational costs and whether or not approval
to discharge would be granted is arbitrary and capricious
(Tricil).

U.S. EPA Response.  Treatment at the Indianapolis POTW was t.
excluded based on the following reasons:                   I

     o    The City of Indianapolis may refuse to accept
          CERCLA wastes.

     o    The City of Indianapolis has required, in the
          past, that the discharge of wastes from a
    .    —groundwater extraction site have no organic
          contamination above the detection limits.
          Subsequently, an onsite treatment system would be
          required.

     o    An increased sewer fee would be imposed based on
          the inorganic priority pollutants in the
          wastewater.  This could substantially increase the
          operational coats.

     pt   The 17-inch sanitary sewer at 86th Street to which
     '•:  .  the> flows from the site would be discharged has
     r^    historically surcharged during wet weather
     ~£~   - (rainfall of 1/2-inch or greater) and bypasses
          occur 50 percent of the time.  Thus, if flows from
          the site were to be piped to the sewer system in
          Indianapolis, additional onsite holding capacity
          would be required during wet weather.

In-Stream Aeration

Comment.  In-stream aeration has been arbitrarily eliminated
because of "low removals of methylene chloride,"  (a
                             47

-------
substance frequently acknowledged as being the result of
laboratory contamination) and because "aquatic life in the
unnamed ditch would experience extreme detrimental effects."
Aeration could in fact be beneficial by increasing the
dissolved oxygen content of the water (Tricil) .

U.S. EPA' Response .  The concentrations of methylene chloride
used for determining removal efficiencies of the in-stream
aeration system were the projected future concentrations
based on actual soil sample data and estimated leaching
rates.

In-stream aeration was eliminated for the potential
detrimental effects to public health and environment in
addition to the poor methylene chloride removal efficiency.
The system would have no means of controlling emissions and
the volatilization of contaminants could pose a risk to
public health.  The detrimental effects to the aquatic
environment from basin construction and turbulence of the
aerators- during operation outweigh any benefit from
increased dissolved oxygen in the stream.  The creek would
also have to be reclassified (see response to stream       *
reclassification in Section 4.6 REMEDIAL INVESTIGATION     f
DATA) .                                                     j"
                                                           ji
Soil Vapor Extraction                              _        -..

Comment.  Since the material detected in the soil on the ECC
side does not represent a significant risk to off site
receptors [sic] the operation of a soil vapor extraction
system would not constitute a significant or cost-effective
mitigation for the site [sic] .  EPA stated that most of the
compounds would decay to levels below the 10   cancer risk
within 10 years, and the benefits of the system for
groundwater collection and treatment are minimal (ECC
Steering Committee) .

U.S. EPA Response.  The U.S. EPA does not consider the
advantages of the soil vapor extraction system to outweigh
the costs.  Thex reasons are stated on page 4-4 of the CAA:
                public health threat would remain in the
           of future ECC site development . and because   •
             of VOC's from the unsaturated zone is not
              to affect groundwater collection and
     treatment, the advantages of soil vapor extraction are
     not considered great.  The expenditure of $2,000,000 in
     present worth for ECC soil vapor extraction for the
     marginal reduction .in health threat is not considered
     cost-effective.  Alternative 7 is not recommended by
     EPA."
                             48

-------
Comment.  Soil vapor extraction is technologically
infeasible and unreliable for the reason that it is
"conceptual in nature" at this time.  EPA explicitly states
that a pilot treatability study would have to be performed
even before a design can be undertaken (Jeffboat and Rock
Island Refining).

U.S. EPA Response.  The statement in the ECC-FS that the
soil vapor extraction system is "conceptual in nature"
refers to the particular layout and sizing of the system.
The technology is feasible and reliable and has been used in
numerous applications similar to the one proposed for ECC.
The ECC-FS states that pilot tests are necessary to further
assess the feasibility for use on onsite soils and to
accurately design the number of wells required, the amount
of piping, and the size of the compressors.  This
alternative was not selected by the U.S. EPA because of its
cost.

Incineration

Comment.  Incineration of ECC soils is technically         4
infeasible and unreliable because air emissions likely     t-
resulting from the incineration could present health and   I
environmental risks equal to or greater than those risks   I
allegedly posed by the ECC contaminated soils (Jeffboat and-.
Rock Island Refining).

U.S. EPA Response.  Incineration of the contaminated soils
at ECC is technically feasible and reliable and has been
used in similar situations.  The design of the incinerator
would include air emissions control equipment so that the
emissions would be in compliance with the appropriate
regulations.  The process of permitting an incineration
facility is very extensive and the potential for risks to
public health or environment would be assessed in detail.
This alternative) was not selected by U.S. EPA.

Onsite RCRA Landfill

Comment.  Construction of an onsite RCRA landfill is
technically infeasible and unreasonable for the reasons that
excavation of the> waste materials could present significant
healt* andenvironmental threats.  Also, such a corrective
action could delay significantly the time in which
corrective action would be undertaken at the site, allowing
the site to be uncorrected during a period when it could
pose its greatest threats to the public health and
environment (Jeffboat and Rock Island Refining).

U.S. EPA Response.  On page 4-5 of the CAA, it states that
an onsite RCRA landfill "is not considered cost-effective by
EPA when the hazards induced by site excavation are
                             49

-------
considered and...a lower cost alternative with a similar
level of protection for public health and environment" is
available.  The reasons for discounting the onsite RCRA
landfill, however/ do not make it technically infeasible.
This alternative was not selected by U.S. EPA.

Comment.' Tables 5-6 to 5-11 of the NSL-FS show
inconsistency in the use of multipliers to estimate total
capital costs for each alternative  (NSL Steering Committee).

U.S. EPA Response.  Specific items in Tables 5-6 through
5-11 were estimated based on a percentage of the estimated
construction costs.  These percentages were modified for
some alternatives to better reflect the level of effort.
For example, the engineering design costs for Alternative 2
were estimated to be about 5 percent of the total
implementation cost or $400,000.  Alternative 3 would
require more level of effort to design the RCRA cap and the
design cost was estimated as $450,000 which is approximately
2 percent of the total implementation cost.  Assuming
5 percent would have resulted in an excessive design cost of
$1,000,000.                                                t
                                                           ^^
Comment.  The cost estimate for the water treatment system |
are particularly suspect because there is no basis for     I
assuming the limitations to be imposed upon discharges
(Jeffboat and Rock Island Refining).

U.S. EPA Response.  The NPDBS permit for the discharge of
the onsite wastewater treatment system has not been
established yet.  In order to prepare a cost estimate,
assumptions had to be made concerning the level of
treatment.  Those assumptions are stated in the FS's and
CAA.  The costs could vary significantly if the discharge
limits are substantially different than those assumed.

4.10  REMEDIAL ALTERNATIVE PREFERENCES

Comment.  The Hoosier Chapter of the Sierra Club supports
the EPA proposal to contain the contaminants coming out of
the site.
•*    ¥;• ' ''''
The Citizen* Environmental Council, Inc. thought that the
proposal rsjcossMnded by the EPA as the preferred remedy
seesj* quit*} acceptable but do not favor onsite treatment of
wastewater.  However, they stated that most or all of their
requisites are addressed by the EPA's remedies.  They also
hoped that site closure and the start of cleanup effort be
underway as soon as possible.

Dee Fox, a private citizen, thought that the EPA's
Alternative 5 is a good one and favored the EPA's plan to
treat leachate and groundwater to remove contaminants rather
                             50

-------
than th* state's plan to just wall them in and urged that
the job  be done "as quickly and thoroughly as possible 1"

Richard  and Elizabeth Idler, private citizens, strongly
encouraged proceeding with institution of Alternative 5 to
eliminate this "environmental menace" because it covers the
site, limits access and future development, minimizes
leachate, intercepts and treats potentially contaminated
groundwater, and provides for monitoring of the underlying
aquifer.

The Toxic Action Project stated that any plan short of the
one chosen by the EPA would be a disservice to the community
of Zionsville.  They also presented their belief that
Congress, EPA, and research organizations have stated that
land disposal of hazardous waste is the least desirable
alternative for handling waste streams and that waste
reduction should be the national policy.

U.S. EPA Response.  The U.S. EPA appreciates the public's
support  of the Recommended Alternative and concern that
remediation efforts at the site proceed as soon as possible j
The U.S. EPA is presently performing Preliminary Design     j-
investigations as a prelude to design, which includes       |
testing  of treatment plant performance for removing
contaminants from collected groundwater and leachate.  The
U.S. EPA is also continuing negotiations with Potentially
Responsible Parties (PRP's) concerning U.S. EPA's selected
remedy in order to assess the degree of participation
anticipated from each PRP in remediation of the site.

Comment.  The only appropriate alternative identified by
U.S. EPA for Enviro-Chem is the ECC FS Alternative 2 (ECC
Steering Committee) .

The U.S. EPA. identified risks that were not shown to be
invalid  [sic] are effectively mitigated by a modified
Alternative 2 in the NSL FS which would delete the soil
cover, removal of creek and leachate sediments, and
rerouting of unnamed ditch and Finley Creek [sic] (NSL
Based^on the lack of a current health threat and absence of
data d» future- health threats, the recommendation that
installation of a cap on the site to minimize future
migration of contaminants, maintenance of the leachate
collection system, and careful monitoring of surface and
groundwater to confirm that the site continues to pose no
health risk should have been made [sic]  (Chrysler) .

U.S. EPA Response.  To date none of the risks identified
have been shown to be invalid.  The information presented in
the FS*s and CAA justifies the combination of the sites and
                             51

-------
the implementation of an alternative that protects not only
human health but also the environment from existing and
future. threats.

U.S. EPA1s recommended Alternative 5 in the CAA meets the
objectives of protecting human health and the environment
and remedial action goals and is the most cost-effective
alternative.

Comment.  Orchard and Sunnen endorse the remedial action
plan set forth in the adopted final order of the IDEM Board
on January 21, 1987, with the understanding that it is
substantially similar to U.S. EPA alternative No. 3 with the
addition of a slurry wall (Orchard Corp.; Sunnen Co.).

In lieu'of its Alternative 5, the U.S. EPA should adopt a
corrective action that is similar to Alternative 2 with the
exception that a slurry barrier wall, consistent with the
state requirements as determined in Cause N-95 adopted by
the Indiana Solid Waste Management Board on January 21,
1987, be installed or alternatively a gr.ctundwater collection
system such as that described in Alternative 4.

U.S. EPA Response.  The objective of a groundwater
interception system is to prevent contaminated groundwater
from migrating offsite.  The objective of a slurry wall is v
essentially the same with the exception that something must
be done with the rainfall that ultimately infiltrates into
the ground and which could build up behind a slurry wall.
The U.S. EPA selected the more active option of collecting
groundwater to achieve the objective because of potential
infiltration and the added benefit that contaminants can
then be removed from the groundwater in the treatment
process.  The State of Indiana believes the U.S. EPA's
alternative is at least as protective as a slurry wall.

Comment.  If one assumes that something must be done then
the most logical choice would be the low cost access
restriction and monitoring alternative identified in the CAA
as Alternative 2.  Ferro submits that "no action"
Alternative; 1 should be selected for NSL and if that is
rejected Alternative 2 should provide adequate protection
and tf" that i» rejected Alternative 4 is the least
objectionable of the remaining seven alternatives
(Ferro Corp.).

U.S. EPA Response.  The U.S. EPA has found that to protect
human health and the environment from existing and future
threats remediation of the site is necessary.  This would
include the interception and treatment of contaminated
groundwater and the installation of a cap that meets the
requirements of RCRA.
                             52

-------
 Comment.  Why can't the Northside site just be monitored for
 now since studies show that contamination levels are
 decreasing?  (NSL/ECC December 11,  1986 Public Meeting.)

 If the distances between the wells  and surface waters were
 increasedr travel times may be long enough to allow
 implementation of remedial actions  after monitoring (NSL
 Steering Committee).

 U.S. EPA Response.  For results on  existing monitoring
 please refer to responses in Section 4.8 Hydrogeology.  The
 U.S. EPA has looked at the contamination at Enviro-Chem and
 Northside and at the results in the remedial investigation
 reports.  The U.S. EPA feels the results justify action.
 The U.S. EPA does not feel that the remedial action goals of
 protecting human health, welfare and the environment at
 Northside and Enviro-Chem are met by Alternative 1,
 Alternative 2 or Alternative 3.  CERCLA does not permit
 U.S. EPA to implement an alternative which allows offsite
 migration of contaminants.  A proposed adequate early
 warning monitoring system which can be implemented has not
 been presented to the U.S. EPA.
 Comment.   Alternative 9,  the RCRA landfill,  is located on  t
 the north side of the Northside site.   Since RCRA sites are |
 only placed in those geological locations best equipped to ~.
 control landfills is the  U.S. EPA saying that that area is a
 good site to put a RCRA landfill (NSL/ECC December 17,  1987
 Public Meeting).

 U.S. EPA Response.  The onsite RCRA landfill was presented
 in the FS and CAA to expand the range  of remediation
 alternatives.  It was proposed for onsite because offsite
 transportation cost would have made the alternative very
 expensive.  When material at a Superfund site is disposed
 onsite it must comply with RCRA requirements.  What is
 presented is a Superfund  alternative that disposes the
 material from Northside in an onsite RCRA landfill.  The
 conceptual design of a RCRA landfill includes an expensive,
'double-lined floor with several feet of clay in addition to
 the geologic material below it, which  is enough to locate
 the facility a* shown in  Alternative 9.  The existing NSL
 does aot have- a bottom liner.

 Comment* -•  The misconstruction and improper application of
 Section 121' of CERCLA requirements has resulted in the
 rejection of alternatives consistent with the NCP and the
 recommendation of an alternative which is not
 cost-effective.

 The comparison of leachate and groundwater contaminant
 concentrations to Indiana Water Quality Standards is not
 applicable and was improperly applied  (Tricil; NSL Steering
 Committee).
                              53

-------
P.S» EPA. Response.  CERCLA as amended by SARA Section 121
dictates cleanup goals and standards.  The treatment of
contaminated soils, refuse, leachate, and groundwater in
order to permanently and significantly reduce the volume,
toxicity, or mobility of contaminants at the NSL/ECC site is
preferred. ..However, the treatment of NSL soils and refuse
would be-nearly impossible because of the large volume and
variety of. materials present and the associated high cost.
Treatment of ECC soils alone would not significantly reduce
the amount of contamination at the combined site.

Since contaminated surface and groundwaters presently are
discharging from the site to Finley Creek, contaminant
concentrations in leachate and groundwater are of concern.
The published criteria are ARAR's which are protective of
warm water aquatic life and human health for ingestion of
aquatic organisms.

Comment.  Parts of Alternative 5 should be implemented as
the need.arises, while groundwater monitoring continues with
time (NSL Steering Committee).

U.S. EPA Response.  There is presently the need for capping^
the landfill and for collecting leachate.  Alternative 5    I"
includes groundwater monitoring for the purpose of remedy   f
performance.  Concentrations of contaminants in groundwater
along the west and south boundaries of the landfill
presently exceed ARAR's, so it must be collected and
treated.

Comment.  The selected EPA Alternative 5 is a complex
remfidial^sction (MSL, Inc.).

U.S. EPA Response.  The selected alternative for the NSL
site effectively mitigates and minimizes threats to, and
provides adequate protection of, public health and welfare
and the environment.  The selected alternative was
technically evaluated on the bases of performance,
reliability, implementability, and safety, and was
determined to be> acceptable.  Complexity of an alternative
is not evaluat^outside of the above considerations.
                             54

-------
                         Appendix A
                                                            I-
                                                            !
GLT614/29-1

-------
                         Appendix A
        EVALUATION OF INDIANAPOLIS WATER COMPANY DATA


Since December of 1983, the Indianapolis Water Company (IWC)
has periodically collected water samples in Eagle Creek
Reservoir watershed, including Finley Creek upstream of the
Highway 421 bridge.  The samples were analyzed for volatile
organic compound content.  In this appendix, the total VOC
concentrations of the samples taken at the Highway 421 bridge
are compared to the estimated streamflow at the site (based
on data from the nearest USGS gauge).

Figure 1 shows the plot of the total VOC's versus time.  It
also shows the streamflow for each day during the period of
December 14, 1986,  (Julian Date * 30664) through October 27,
1986, (Julian Date - 31712).  The plot shows that the samples
were collected during a variety of flow conditions, and higher
VOC concentrations tend to be associated with lower flows.

In Figure 2 the stream data has been sorted from highest (left
side) to lowest (right side) flow and plotted against the pejrcent
of time each flow has been exceeded.  The VOC concentration
observed when each flow occurred is plotted at the same nor-
izontal plotting position.  As shown in Figure 2, the highei
VOC concentrations occur when the flows are low.

The strength of this observed relationship was statistically
evaluated for 1,1,1-tetrachloroethane (1,1,1-TCA).  As shown
on Figure 3, 1,1,1-TCA was found to relate linearly with the
log of the flow with a coefficient of variation of 0.64.  This
can^be interpreted to mean 64 percent of the variation in the
1,1,1-TCA concentration can be directly related to the vari-
ation in streamflow.

If the source of the VOC's, and 1,1,1-TCA in particular, were
a constant discharge such as froa a leaking drum or a point
source discharge, then the concentrations should decrease
linearly as flow increased and the coefficient in the
regression equation would be -1.0 rather than -0.57.  If the
sourc*ype)x* swrffcce runoff, the coefficient would approach
0,0 mjajoik concentration would be more independent of flow.
The, -$|$1[.indicates some dilution.at higher flows.  Conse-
q^entIjpp;tB4r source appears to be affected by factors
affectu»9> natural streamflow.  The -0.57 coefficient is con-
sistent with that expected of a contaminant transported to
the stream through the groundwater—the source quantity varies
with streamflow but does not vary as rapidly as surface flow.

Table A-l is a summary of the IWC data showing the sampling
dates, compounds observed, and concentrations.  The table also
presents potential risk associated with recreational use of
                             A-l

-------
0
   450
   400
   350
300
H 250
3J  200

9  150
o
£  100
s
Ik  50
         STRIAMFIQW 1ST
         TOTAL VOLATILIS
      30.0
                    *

                 MU
            30.S

                                              t
      Id
31.4
31.6
                               (Thousands)
                              JULIAN
      f
      .jH-J
318
                                                      Appendix A
                                                      FIGURE 1
                                                      INDIANAPOLIS WATER COMPANY (IWC)
                                                      DATA SUMMARY
                                                      FLOW AND TOTAL VOLATILES
                                                      NSL/ECC RS

-------
    50
^v
s
    40-
    30
8
    20
v v
Ik
O

I
Ik
    10
                       fTREAMFLOW
                       TOTAL VOLATILES/10
                 0.2
                 PERCENT OF TIME FLOW EXCEEDED
                                   , I
                                              Appendix A
                                              FIGURE 2
                                              SNDQANAPOLIS WATER COMPANY
                                              FLOW FREQUENCY AND TOTAL V
                                              NSL/ECC RS
                                                                   TILES

-------

I
 I
                                      a OBSERVED TCA
                                      + CALCULATED TCA
                                   r2 - O.M
                                   log TCA - 130 - 0.57 log Q
                           STREAMFLOW (CF$)
Appendix A
FIGURE 3
INDIANAPOLIS WATER COMPANY (IWC)
DATA SUMMARY
1.1.1 TRICHLOROETHANE (TCA)
VERSUS TOTAL STREAMFLOW
NSL/ECCHS

-------
                                                                   IMU at
                                         IWIMVU.IS UAItl ON«kV MIA tUM I3M Id IW6 III mCUGMfc Kl HIM
                                                          *&MMI«tf& SUMW
O-JM-44
12-Jw-M
21-JM-M
K-ftk-M
24-hrM
ii-ftrtt
•7-Jw«4
2ft-J*-M
«9-M-«t
                                M7.I
                                27.4 114.1)
  Hit      1,1,1-IUM.I-KI  CIS-I.2-KE

14-tar-U  M     j.l
              114

              *.S           v
              J7.I
              114
              111
               14

               9.1
               2.4
               19
               If

              ft

               2.5
              11.2
               '•i
              II. 7
             ' 9.2
               II

              If
               4.1     1.1        111
              14.4     4.4        71411.11
              J4.4     4.1        54.1 H9I
               1.1                1.1
                2     19          •
               9.7               111
               4.1     1.1        11.1
               14     19        11.9
               II     1.9        111
               II     1.1         7.1

               tt
                11
                14
              91.2
               174
              217
               4.4

•7-M-K
21-ftMl
 1.1
 4.4
 4.1

 19

 1.1
 19
 1.9
 1.1

 19
II*
211
111

1
 1.1

 4.1
M MicMw Mrtoi •*•• M*
                                 *:
•Vte«
I9-M-I4
27-fct-«
               114
 IN 111!
 Ill

92.1
22.7

112
                                         ICE

                                          2.2
                                          11.2
                                           II 12.21
                                          44.4
                                          «.« II.U
                                          29.4 Ul)
                                          1.4
                                          4.9

                                            1
                                          1.1
                                          2.4
                                          2.1

                                          2.1
                                             2,1

                                            14.1
                                             1.9
                                             1.2
                                           1.1
                                           4.4
                                           *J
                                           H9
                                           19
                                           1.2
                                           19
                                           19
                                              .
                                             4.1
                                             2.1
                                             4.4
                                                                M.UUFUM
                                                                              1,1-01   flCN
                                              OUttMM  IUI«.
IS
11
I.T
i.; n.ii
                                                      19
19
1.1 1191
                                     4.4

                                     1*



                                     1.9 1191




                                     19
                                                                                19
                                                                                  1.4
1.1

19
 41 (191
2.4 H9I

19
19
                                                                                2.2     19
                                                                      2.4
                                                                                   1.4
                                                                                         II
                                                                                                    19
                                           IS


                                           19

                                           4.2
                                           2.2
                                           ll.l
                                           IS
                                                                                                    11
                                                                                                             19
                              tnmUL II Imtiw MM.
                           ftta Ina » U Ucatiw MM.
                           !• fjfli Or** «t 24tt ttrMt.
                           islrt wtarad w Iki Ukto «IS */l »»
  	  	 	|w OMCB}
TwtMhlwMttaM M«M i* fMtf CTMH M MM 421 w S/Vlfc «l II «|/l.
           M«t«4 M fully CM* at MW 421 «• V2I/I4 M trM iMtjt IraortM M IS «»/ll.
                  -     •  	   1/21/11 «t lr«* I«*U IranrM M 19 */IK
 II Micilw HKMlrMitM
             *4KM i* trie*
             rt «ly o«c«i
   ftrwafo* M«M i» f i*l«f CNrt at MW 421 • 1/21/24 *
   I,I,MDI *tacM ia f Uliy CM* tt Mr 421 w Wtk tt
 IMESIUM V
 tim

 IHttlKH V
 WIEIUUS
•GWIIOH
WUICMMIC
         4.X-H


         I.K-W



         2.4E-4I
                                                    nw •HIHUIMU ID wtms OKEJIIWIUK

                                                      I.4E47       4.X-M       ».*-«' 2.7C-M
                                                    7.44-11
                                                       .IC-tt
                      !.«-•  llf-W
                                                                  4.3E-M
                                                                                               i.u-w
                                                                                                 2.4C-I4
                                                                                                                       KIECIEO Ml EMU
                                                                                                                       DUX
                                                                                                           I.I
                                                                                                              1.2
                                                                                   2S.J
                                                                                   W.I
                                                                                   lit
                                                                                   41* i ICE I if/I
                                                                                  144.2 • Hf II «t/l
                                                                                   411 -        V
                                                                                   £.4
                                                                                    2.1
                                                                                   114
                                                                                    14
                                                                                   J4.I
 44.1                   1
 417
 II
 91.2
 4.9
in. 4
 7.7
 41«
 119 » dilorofora 1. 1 ^/l
 27.4
 29.9
l*17*dil«r«(gr*19«|/l
134.1
 4.7
 ll.l
 211  t cit -1,2-BX iSVl

31 1. 1
214.4
XI*
 H2
 J12

 42.1
                                                                                                                        IOIM. GMCIMBEMC IISK
                                                                                                                              IE -I?
                                                                                 n-ti

-------
Finley Creek upstream of Hwy 421 bridge due to the calculated
averag*; concentration of the various VOC's observed.

Table A-2'is the presentation of sampling results from a
June 8 and 9, 1987, reconnaissance of Finley Creek and
unnamed dit.ch.  The sampling locations correspond to those
shown in-Figure 4.
GLT614/30
                             A-2

-------
                                                                      imuu
                                           fllU 12
                                           I Uf III

                                                                                                                                                      H I <•'
fit*      MM*
                              .
                                          ft*.
                                                                                                 AH
                                         ft/Ml       Ic/lf
MCUIC CWNM lu/ll
IMMIIIM(IMMIlMi«M*H«IMMMM«IMtMIM««MM«WM«MMMMMMMMMI«MMIM
     NUflUS
                        .IJ
         IM IMXI
UMIN
                       I.IJ
 p

 *¥M8!lW HIM)
                                  I.S  *

                                  M  '
                                  I1).
m
                                             IS  i
           S.I

           it:
I.SJ
           8:
                                    i.u
                                        aiiiji     snail     uiJi-11     uiu-ii     SKIUM

                                                    C22II        bilS       C22II       C22II
                                               l.» J
                                               IS  i
                                               I.SJ
                                               i.)

                                               i!:
                                                                                              Mill II     	
                                                                                               I Ml       IMI
                                                                                                                                                           II
                                                                                                                                                           I
                                                                                                                                                        C221I
                                                                              1.1
i.u
i:NUfiii$	ii'i	ii	ii	ii's	is!i	''"ii'.i	i"
                      1.1
 ,
1:1

 si
                                                                  4S
                                                                  n
                                                                "iiiii"
                                                                                               '    "!i    '     "I    '    sli   i    2J?!    '     1!    i     6!i
                                                                                             i||JlllMlllfllMlllUUIIIIIIIIl!llllMIIIMIIlilMIIIMt«llllJllMMIIII«»lliMIMU»i
                                                                                                           MlllltMIMMMUKMIIIII
           fOOIMIU:
                   • •  ItJjeiUi cwHul H*Ui«i|i ii4*U(itl . e«Keitrilioi U iitiutel to kc Uu Uu I «|/l lM ut»ra4 U Uklt l*r
                   J •  lUicllW CWfMM H*ltilll| iMtllflll , CMCUlritlM il MllMiM.

-------
l-Stfll
C«ttral
 HUIIC CttfMMS
ittMMMMItMMItlitlU
      NUtlUS
tU NUflllf
            IMTMTIS:
        fi1
       ONI
                                                  TO'
                                                    Ctttl
                                                                        TO*     TW
                                                                         ClJJi       dill
SMIIt-ll
 (l-ll
 Clilt
                                                SKD2II
                                                 Mil
                                                 C12IJ
                                                                                                                              SK;12



                                                                                                                             SMI12I2
                                                                                                                             I-MI
         i>
                                  a:
                         I
                                            '8
                                                      14 «
                                                      'U
                                                        '!:(
                                                        I >  «


                                                          I J

                                                                            :1
                                                                           IS  (
                                                   IJJ
I i *
'II
          I




          14

          lilt
                                                                                     III
                                                                                                4

                                                                                                l.i
                                                                                  'i!
                                                             m        421
i	iiiii	jifi	itji'i	m.\	jii'i	itiijj	mirj	
^««,_™
                                                                                                          2M
                                                                                                          .1;
                                    H*iUi«l| iiietilirt . CMCutriliu it utiMiel to ke Itu tku I «|/l (l.i uUru" U Uklt fw rtforliu
                          citu t*i*uA MtillMli iuilifM . eueulutlu it tttiutu*.              . / »f«HMMf
                                                                                                                             IH
              22


          1.2 J/1.4 J




              14
* 4 •

14 •



• 4 •


 Ik


12 J




 in
                                                                                                                                                 C22II
                                                                                                                    «|
                                                                                                                  111 J / 1)1.4    III J


                                                                                                                           I    4)   I
                                                                     II -  4«


                                                                    "ii""i«"
                                                                                                     iig

-------
                           mum imi12
                        Ul/ICC SIUKI UIII Mil
                       ucouiftiici suniK wt
                         lUMSIIUUS SWUll
           SufU NUl
         Sutlc UciIlM   IUU       IU1I
          CMtnl bkr   C22U
  NUIIC CMNHK (M/ll
IMIMUIMMIIUMMilMIIIIIMIIIIIMIMMIMIIMIMMIIM

       NUtlUI
tifu'wutius
                       u     i  1,1     j
                    WIIMtlMMIMIIIIIMMMIIM

-------
   NOMTHMOf SANITAIIV
        LANOTIU
                                               2.7 CF8
o          800

SCALE IN FUT
                                           Appendix A
                                           FIGURE 4
                                           JUNE 1987
                                           SAMPLING LO
                                           NSL/ECC RS
IONS

-------
                          Appendix B
GLT614/29-2

-------
                                                               Appendix B
                                                       IM>n OF COMMENTS RECEIVED
           Bepresentinq
BOC Technical Steering
NSL Technical Steering
Jeffboat
Bock Island Befinlng Cor*.
NSL, Inc.
TW, Inc.
Trlcll Eovironnental Senrlces, Inc.
Merman Haldron Contort Tables
Orchard Corp.
Sunnen Product* Co.
City of Indianapolis
Jone* Chemical*, Inc.
Chrysler Motor* Corp.
Tberaoset Plastics, Inc.
Porro Corp.
Metalworking Lubricants Co.
Sierra Club, Booster Chapter
Citlsena Bnvlronaental Council •
Tbenselves
Herself
Toxic Action Project
                                                   Site
                                                 BOC

                                                 NSL

                                                 NBL/BOC

                                                 MBL/KC

                                                 NSL
   Pate
2/12/87
2/27/87.
2/28/87
2/27/87
2/27/87
2/28/87
EOC Technical Comittee
BRM
Barnes & Thoraburg
NBL/BOC
HSL/ECC
•DC
•oc
•DC
NSL
NBL/BOC
NSL
NSL/BOC
NSL
NSL/BOC
NBL/BOC
NSL/BOC
NSL/BOC
NSL/ECC
NSL/BCC
2/27/87
2/27/87
2/27/87
2/12/87
2/23/87
2/27/87
2/27/87
2/25/87 C
3/2/87
12/31/87
2/26/87
2/27/87
2/14/87
2/10/87 ft
2/24/87
U12/87
1/20/87 '
. Mone
Baker fi Daniels              :
BIS
Baker C Daniels
ETS
Parr, Bicbey, Obrenskey C Morton
Nest
TRH
Mishkin, Croe«r, Eaglesfield fc Maber P.A.
Geragbty & Miller
Dunlevey, Manan & Furry
Orchard Corp.
Sunnen Products Co.
City of Indianapolis
Nixon, Hargrave, Devans S Doyle
Chrysler Motors Corp.
Tberaoset Plastics, Inc.
Squire, Sanders fi Denpsey
Metalworklng Lubricants Co.
Garelick, Cohen £ PlshMn
Douglas P. Johnstone,  M.D.
Richard and N. Elisabeth  Idler
Dee Fox
Grant Smith, Coordinator
GLT614/31

-------