United States        Office of
Environmental Protection   Emergency and
Agency           Remedial Response
EPA/ROD/R05-91/166
August 1991
Superfund
Record of Decision:
South Macomb Disposal #9,
9A, Ml

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60272-101
REPORT DOCUMENTATION i. REPORT Ma 2.
PAGE EPA/ROD/R05-91/166
4. TMeendSuMMe
SUPERFUND RECORD OF DECISION
South Macomb Disposal #9, 9A, MI
First Remedial Action
7. Au«K>r(s)
». Performing Orgslnlzrton Nun* snd Address
12. Sponsoring OrgsrtuUon Nune tnd Address
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
3. Recipient's Accession No.
5. Report Dste
08/13/91
6.
8. Performing Organization Rept No.
10. Pro(ecVTask/Wort( Unit No.
11. Contrad(C) or Grant(G) No.
(C)
(G)
13. Type of Raport & Period Covered
800/000
14.
 IS. Supplementary Noln
 18. Abstract (Unit: 200 words)
  The 159-acre South Macomb Disposal #9, 9A site contains  two inactive municipal
  landfills in Macomb  Township,  Macomb County, Michigan.   Land use in the area  is
  predominantly agricultural and rural, with several  adjacent residences.  A  small
  stream, the McBride  Drain,  runs along the western and southern boundaries of  the site,
  and there is a possible wetlands area located at the  site.   Until 1989, the estimated
  34 residents in the  immediate vicinity of the site  used  shallow and intermediate
  aquifers associated  with contamination from landfills as their drinking water supply.
  From 1968 to 1975, South Macomb Disposal Authority  (SMDA),  a municipal corporation,
  used the site to  facilitate the management and disposal  of  municipal refuse for  five
  towns in Macomb County.  SMDA acquired the 75-acre  area  #9  in 1968, accepted  680,000
  cubic yards of municipal waste, and capped the area with soil in 1971.  Subsequently,
  SMDA acquired the adjacent 84-acre area 9A in 1970, filled  it with 1,200,000  cubic
  yards of municipal waste,  and capped the area with  a  mixture of sand, clay  and silt  in
  1975.  As a result of  reported fish kills and continued  reports of leachate seepage
  into McBride Drain,  a  number of State investigations  between 1976 and 1982  verified
  that the site was the  source of the leachate problem  and prompted SMDA to upgrade and

   (See Attached Page)
  17. Document Analysis a. Descriptors
   Record of Decision - South Macomb  Disposal #9, 9A, MI
   First Remedial Action
   Contaminated Medium:  gw
   Key  Contaminants:  VOCs  (benzene,  toluene),  other organics  (phenols),  and metals
                        (arsenic  and  chromium)
   c. COSATI Held/Group
18. AvailsbUty SUtermnt
IS. Security Class (This Report)
None
20. Security Clsss (This Page)
None
21. No. of Pages
75
22. Price
 (See ANSt-ZM.18)
                                     SM Inttructiont on Revertt
OPTIONAL FORM 272 (4-77)
(Formerly NTIS-35)
Deportment of Commerce

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EPA/ROD/R05-91/166
South Macomb Disposal #9, 9A, MI
First Remedial Action

Abstract (Continued)

expand leachate collection systems along various portions of area 9A.  From 1983 to 1984,
the State investigations detected VOC-contaminated ground water in several residential
wells near the site.  Consequently, from 1985 to 1988, SMDA constructed an additional
leachate collection system on area #9, and a slurry wall across the northern portion of
area #9.  In 1989, Macomb Township connected residences near the site to the municipal
water supply.  This Record of Decision (ROD) addresses onsite contaminated ground water
as Operable Unit 1  (OU1).  A future ROD will address the landfill contents as OU2.  The
primary contaminants of concern affecting the ground water are VOCs including benzene and
toluene; other organics including phenols; and metals including arsenic and chromium.

The selected remedial action for this site includes installing extraction wells in the
intermediate aquifer, both within and outside the site boundary and subsurface drains in
the shallow aquifer along the periphery of the waste deposits in both sites #9 and 9A;
collecting ground water and leachate in a series of collection sumps, followed by pumping
to the onsite ground water treatment system; treating the contaminated ground water
onsite using air stripping, followed by granular activated carbon,
oxidation/precipitation, and granular media filtration, with onsite discharge of the
treated water to McBride Drain; disposing of any treatment residuals offsite; extending
the existing slurry wall along the east side of area #9; providing a municipal water
supply to any residences within a one-half mile radius of the site that are not currently
attached; conducting long-term monitoring of ground water, surface water, sediment of
McBride Drain, leachate, air, and residential wells; and implementing institutional
controls including deed and ground water restrictions, and site access restrictions
including fencing.  The estimated present worth cost for this remedial action is
$9,264,000, which includes an annual O&M cost of $224,000.

PERFORMANCE STANDARDS OR GOALS:  Chemical-specific ground water clean-up goals are based
on the more stringent of State standards or SDWA MCLs, and include benzene 2 ug/1
(State), toluene 100 ug/1  (State), phenols 1,100 ug/1  (State), arsenic 1 ug/1  (State),
and chromium 100 ug/1  (MCL).

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                           DECLARATION
                             for the
                        RECORD OF DECISION

       South Macomb Disposal Authority/ Landfills 9 and 9a
                     Macomb County, Michigan
Statement of Basis and Purpose                                 ^

This decision document presents the  selected  remedial action for
the South Macomb  Disposal  Authority, Landfills 9  and 9a,  .(SMDA)
Site,  in Macomb County, Michigan, which  was chosen in accordance
with the requirements of the Comprehensive Environmental Response,
Compensation, and  Liability Act of 1980 (CERCLA), as amended by the
Superfund Amendments and Reauthorization Act of 1986 (SARA) and, to
the extent practicable, the National Oil and Hazardous Substances
Pollution Contingency Plan (NCP).  This  decision  is  based  on the
administrative record for this Site.

The State of Michigan concurs with the selected remedy.  The letter
of concurrence is attached.
Assessment of the Site

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

The  selected  remedy  is the  first  operable  unit  at the  Site.
Operable units are discrete actions that comprise incremental steps
toward the final  remedy.  The nature of the second operable unit to
address  the  landfill  contents  will  be  assessed  during  the
performance of the first operable unit.  The selected remedy treats
the greatest  risk  posed by conditions at the Site,  exposure by
ingestion or direct  contact with contaminants in the ground water.
The  treatment will  achieve  substantial  risk reduction  through
extraction  of the  contaminated ground  water at  the Site,  and
treatment to health-based levels.

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The major components of the selected remedy include the following:

     •    Installation  of  ground-water  extraction  wells and  a
          slurry wall to control the plume of contamination;

     •    Construction of a collection and on-site treatment system
          for contaminated ground water;

     •    Long-term environmental monitoring;

     •    Connection of all residents  in the immediate vicinity bf
          the SMDA Site to a municipal water supply.


Declaration of Statutory Determinations

The  selected  remedy  is  protective   of  human  health  and  the
environment, complies with Federal and State requirements that are
legally  applicable  or relevant  and  appropriate to  the  remedial
action  and  is  cost-effective.    This remedy utilizes  permanent
solutions  and  alternative  treatment technologies  or  resource
recovery  technologies  to the  maximum  extent  practicable,  and
satisfies  the  statutory  preference   for remedies  that  employ
treatment that reduces toxicity, mobility, or volume as a principal
element.

Because this remedy will result in hazardous substances remaining
on-site  above health-based  levels,  a  review  will  be  conducted
within five years after commencement of remedial action to ensure
that the remedy continues to provide adequate protection of human
health and the environment.
       $'. Adamkus
Regional Administrator
/Date/

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                        TABLE OF CONTENTS

A.  Site Location and Description	1
B.  Site History and Enforcement Activities 	 1
C.  Highlights of Community Participation   	4
D.  Scope and Role of Response Action	4
E.  Summary of Site Characteristics 	 5
F.  Summary of Site Risks   	9
G.  Environmental Standards not met at the Site	14
H.  Rationale for Further Action  	  16
I.  Description of Alternatives 	  17
J.  Summary of Comparative Analysis of Alternatives ...  22
K.  The Selected Remedy	26
L.  Statutory Determinations  	 	  28
Responsiveness Summary  	  35

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                        FIGURES  and TABLES

Figures
1.  Location Map	1
2.  Site Map	1
3.  Hydrogeology 	 5
4.  Extent of Ground Water Contamination 	 8
5.  Alternative 2, Environmental Monitoring  	  17
6.  Alternative 2, Aquifer Monitoring Locations  ....  17
7.  Alternative 3, Components   	  18
8.  Alternative 3, Ground-Water Treatment Schematic ... 20
9.  Alternative 3, Municipal Water Supply Map 	 21

Tables
1.  Contaminant Concentrations  in Leachate 	 8
2.  Contaminant Concentrations,  Shallow Aquifer  	 8
3.  Contaminant Concentrations,  Intermediate Aquifer ... 8
4.  Distribution of Contaminants 	 9
5.  Risk Assessment Summary Table  	  12
6.  Chemicals of Concern in Ground Water, Concentrations and
    Cleanup Standards 	 14
7.  Cost Comparison	26

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                         DECISION  SUMMARY
A.   Site Location and Description

The South Macomb Disposal Authority (SMDA)  Landfill site is located
at Foss Road and 24 Mile Road, in Macomb Township,  Macomb County,
Michigan (see Figure 1) , about 25 miles north of Detroit, Michigan.
The  159-acre site  consists  of two  adjacent,  rectangular-shaped
municipal landfills,  sites  9 and 9a,  as  shown in Figure  2.  The
landfills received municipal waste from 1968 until closure in 1975.
                                                               i'
The surrounding area is  generally rural/agricultural; residences
and farm  fields are located to the  north, east, and west within
several, hundred feet of  the landfill; a  golf  course and McBride
Drain, a  small  stream,  border the south.   Macomb Township has a
population of approximately 20,000 people.   About 2,200 people live
within a three-mile radius of the site, many of whom have private
water wells as their drinking source.  Thirty-four residences are
located in the immediate  vicinity of  the site, along 24 Mile Road,
Foss^Road, and Card Road.  Most of  these  residents,  particularly
those whose wells  were historically affected by the off-site plume
of contamination,  are now attached to a municipal water supply.

The drainage system for the site and  immediate vicinity is McBride
Drain,  a   small   stream  heavily   used   for   recreational  and
agricultural purposes.  McBride Drain flows along the western and
southern borders of the site, then south to the  north branch of the
Clinton River, a distance of  approximately 1.5 miles.  The Clinton
River discharges directly into Lake Saint  Clair, located northeast
of Detroit.   The average  flow for McBride  Drain is 1.81 cubic feet
per second  (cfs).    The average flow  for the  Clinton  River is 127
cfs.

No  wetlands were  identified  by the  State  of  Michigan  or  the
Department of Interior upon  initial review of the workplan for the
Remedial Investigation (RI) or  consequent reviews of the RI and the
Feasibility Study  (FS).  A preliminary environmental assessment has
been performed by  the  U.S.  Environmental  Protection  Agency (EPA)
that indicated wetlands may be present; a  more in-depth assessment
will be performed during the design phase of the remedial action.


B.   Site History and Enforcement Activities

The site was operated as  municipal landfills by the SMDA from 1968
to 1975.  SMDA is  a municipal corporation  formed in the late 1960s
by five towns in southern Macomb County,  Roseville,  East Detroit,
Center  Line, Warren,  and St.  Clair  Shores,  to facilitate  the
management  and disposal  of  municipal refuse  for   its  members.
SMDA's  board of directors  consists  of mayors  from  each  of  the
member towns.  The  landfills consist entirely of municipal waste.
While hazardous substances are present in  the leachate produced in

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 SOUTH  \
MACOMB

                       FIGURE 1
South Macomb Disposal Authority
       Site Location Map

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     '    '..21
SOURCE: U.S.G.S. 7.51  topographic map.
Waldenburg Quadrangle  Michigan.
Dated 1968 Photorevised 1973 and 1980
Scale: K-2000'.
                                     QUADRANGLE LOCATION
                                                                          2000
      LEGEND

      DESIGNATES DISPOSAL
      SITES  9 AND  9A
ORIGINAL
                                                   FIGURE 2

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the  landfill,  there  is  no documentation  indicating that  non-
household  waste  as defined  by  the Resource  Conservation  and
Recovery Act (RCRA)  and/or industrial waste was disposed of at the
site.

SMDA acquired site 9, 75 acres, in 1968 and operated it until 1971.
During this time, the  site  accepted  about 680,000 cubic  yards of
municipal waste,  some  of which  was  placed directly  into former
mining pits containing water.   In 1971, the site was  closed and
capped with soil.   Subsequent reviews of site conditions by the
Michigan Department of  Natural Resources  (MDNR) indicated that the
soil  cover thickness  was  less  than the two  feet  required  by
Michigan law.   Title to site 9 was transferred to Macomb Township
in 1975.

As site 9 approached its operating capacity in 1970, SMDA purchased
84 acres of adjacent farm land to the west.  This  site, called 9a,
began operations in  1971,  accepting about  1,200,000 cubic yards of
municipal waste.   In 1975, at the completion of filling operations,
site 9a was closed and  covered with two feet of a mixture of sand,
clay and silt.

During and after the operation of sites 9 and 9a, leachate from the
landfills  seeped into  McBride   Drain and  flowed onto  adjacent
property,  causing a ground-water contamination problem.  Leachate
discharges from the site were observed by the MDNR in 1971, 1975,
1976, and 1983.   Complaints of  fish  kills and  continued  leachate
seepage into McBride Drain prompted an MDNR investigation in 1976.
The investigation verified the complaints  and resulted in improved
leachate management practices  by SMDA.  SMDA also  improved erosion
and  sedimentation controls, tilling  and regrading the  landfill
surface.   However,  leachate  outbreaks  occurred  again north and
south of  the  site  in  1980 and  1982.   In  response  to  the  1980
leachate outbreak,  SMDA  installed a leachate collection system
along the south-central and northern portions of site 9a.

In 1982, residents north of the  site complained about a red slime
that seeped into their  basements.  The substance was tested by the
State and  found not to  be  toxic.   Residential  wells were  also
tested.   No contamination  was  found in  the  samples.    In 1983,
residents near the landfill  filed suit against SMDA, Macomb County
Health Department, Macomb Township,  Michigan Department of Public
Health,  and the MDNR,  for  damages resulting   from  the  site.
Subsequently,   the  State  of  Michigan  joined  the  residents  as
plaintiffs against SMDA and Macomb Township.  The same year, the
Michigan Department  of Public  Health detected volatile organic
compounds (VOCs)  in two  residential  wells near the site.   These
residents were  advised not to  drink their water and the State
supplied bottled water.  In 1984, two more residential wells were
determined to be  contaminated.  In 1985, the State Attorney General
obtained a  circuit court  order  requiring  SMDA  to  construct  a
leachate collection  system on site 9 similar to the one on site 9a.

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MDNR proposed to  EPA  that SMDA sites 9 and 9a  be  considered for
cleanup under the Superfund program.  On June  10,  1986,  the site
was  placed on  the  National  Priorities List  (NPL)  pursuant  to
Section   105   of  the   Comprehensive  Environmental   Response,
Compensation and Liability Act  (CERCLA), 42 U.S.C.  Section 9605,
with a Hazard Ranking  System Score  (HRS  score) of 35.5, because of
proximity to domestic water supplies  and historic  information on
domestic well water quality.   In May of 1987,  notice letters were
mailed to potentially responsible parties (PRPs) at the site, the
South  Macomb  Disposal  Authority  (owner/operator)   and  Macomb
Township (owner),  inviting them to negotiate for the conduct of the
Remedial  Investigation/Feasibility  Study  (RI/FS).     The  PRPs
declined the opportunity to perform the RI/FS.

Under an existing remedial contract,  EPA assigned  the consulting
firm Of CH2M Hill the RI/FS project.  Field work began in October
of 1988, about the time  that SMDA, under a court order obtained by
the State, began construction  of  a slurry wall across the northern
edge of site 9.  In 1989, Macomb Township,  under a Consent Decree
with the State, began the process of connecting residences around
the site to municipal water.  This process was completed by fall of
1990.  This Consent Decree provides  for  residences to be hooked up
to the  municipal  water  supply if contamination originating from
SMDA sites  9 and 9a  is  detected  in their water  supply  in the
future.

EPA completed the RI Report in August of 1990.   The  draft FS was
released in September  of 1990.  In the intervening years since the
May  1987 negotiations  for performance of  the RI/FS,  EPA has
determined  that  the  five  member  townships   of SMDA  are  PRPs
individually liable for CERCLA cleanup  costs at the  site,  as are
the  Macomb  County Road  Commission,  and  Van  Dyke Disposal and
Wiegand Disposal,  both transporters.   EPA issued notice letters to
SMDA, its five member  towns, Macomb Township, the Road Commission,
and Van Dyke Disposal  in March 1991, and Wiegand Disposal in July
1991.  EPA continues to review the evidence concerning PRPs and may
notify additional parties when it  issues notice letters inviting
PRPs to negotiate to  perform  the Remedial  Design/Remedial Action
(RD/RA) at the site.

In April 1991, a State of Michigan trial court judge ruled in the
lawsuit instituted in  1983 that SMDA must undertake for both sites
9  and   9a,  remedial  measures  to  inhibit  "leachate  formation,
breakouts and  off-site migration"  of  contaminants.   The  court
required grading and an  impermeable  cap  consisting of at least "an
increased slope and synthetic liner to ensure against percolation."
Also the court ordered installation  of slurry walls and a leachate
collection system in addition  to  those already in place.  Finally,
the  court  ordered SMDA to perform  "ground-water pumping  of the
contaminating plume by the purge well method."

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C.   Highlights of Community Participation

On October 6,  1988,  EPA  hosted  a "kickoff"  meeting at the Macomb
Activities Hall in Mt. Clemens,  Michigan.   A community relations
plan  was  finalized   in  May  1988.    An RI update  letter  was
distributed to the community in July of 1989. A public meeting was
held on January 20, 1990 to provide the community with test results
from residential well sampling and answer questions.

The RI/FS Report for the SMDA site was released to the public for
review on October 1,  1990.  The Proposed Plan was released to the
public for comment on May 1, 1991.  These two documents were made
available to the public  in  both the  administrative record and an
information repository maintained at  the  EPA Docket Room in Region
V and at  the Macomb  County Public Library  located  at 16480 Hall
Road,. Mt. Clemens, Michigan. The notice  of  availability for these
two documents  was published in  the Macomb County  Daily on May 1,
1991.  A public comment period on the documents was held from May
1, 1991 to June 6, 1991.  In addition, a public meeting was held on
May  6,  1991  at the Senior Activities  Center  in Mt.  Clemens,
Michigan.   At  this  meeting,  representatives  from EPA  and MDNR
answered  questions about problems at  the  site and  the remedial
alternatives  under  consideration.   A response  to the comments
received  during this  period  is  included  in the Responsiveness
Summary, which is part of this ROD.

The public participation requirements  of CERCLA  sections 113 (k)
(2)  (B)   (i-v)  and   117  have  been met  in  the remedy  selection
process.   This decision document  presents  the  selected remedial
action for the SMDA  site,  in Michigan, chosen in accordance with
CERCLA,  as  amended  by SARA and,  to  the extent  practicable, the
National  Contingency  Plan  (NCP) .   The decision for  this site is
based on the administrative record.


D.   Scope and Role of Operable Unit Within Site Strategy

The cleanup goals for this  operable unit are to:

     •    Prevent direct  contact with leachate  and contaminated
          ground-water;

     •    Prevent off-site  migration of  the contaminants in the
          ground-water; and

     •    Remove and treat  contaminants in ground-water.

These goals will be met through  the proposed cleanup action, which
includes  an  extension of   the  existing  slurry wall  on  site 9;
installation of ground-water extraction wells to control the plume
of contamination; a  collection/treatment system  for contaminated
ground-water;  long-term environmental monitoring of ground-water;

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and connection of all residents in the vicinity of the SMDA site to
the municipal water supply.   The proposed cleanup action  is the
first operable  unit at  the  site.   Operable units are  discrete
actions that comprise incremental steps toward the  final remedy.
The  nature  of  a second  operable unit to  address the  landfill
contents will be assessed during performance of the first operable
unit.
E.   Summary of Site Characteristics

The remedial investigation involved extensive sampling and analysis
of ground-water, air, surface water, sediment, leachate, subsurface
soil, and  surface  soil.   Water samples were collected  from some
residential  wells  around  the site.    Site  geology,   landfill
characteristics,  and ground-water flow patterns were also examined.

Based on the results of the RI, EPA determined  that the greatest
threat to human health  and the  environment by this site is through
exposure,  by direct contact  or  ingestion,  to  the VOCs,  semi-
volatile organic compounds  (SVOCs), and inorganic compounds, such
as m'etals,  present  in the leachate and ground-water.  The following
conditions were observed at the site:

     1.    Topography

     The area surrounding the site is basically flat.  The landfill
     operation has  not resulted in any significant  increase  in
     topographic relief.    The elevation of  the ground  surface
     surrounding the landfill  ranges from approximately 605 feet
     (ft.)  to 615 ft. above  mean sea level (MSL) .  The site surface
     rises  approximately  6  to 8  feet above  the  original land
     surface.

     2.    Hydrogeology

     Three aquifers are located beneath the SMDA site:  a shallow,
     an intermediate,  and a deep aquifer.   A  ground-water divide
     defines an approximate  ground-water basin containing about 95%
     of the SMDA site as shown  in Figure 3.  Ground water on either
     side  of  the  divide may flow parallel to  or away  from the
     divide but never across the divide into another basin.  The
     three aquifers are considered Class II aquifers  by EPA because
     they  are  currently  used  or  are potentially  available for
     drinking water or other beneficial uses.

          a.     Shallow  Aquifer.     The   shallow   aquifer  is
          discontinuous in  nature.   This unit  generally includes
          saturated surficial  sands,  fill,  and/or  refuse  where
          these materials reside above the shallow clay lacustrine
          unit.  Where the  lacustrine clay is absent, the shallow
          aquifer  material  is  contiguous  with the intermediate

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  0         «00

FIGURE  3
MYOnOCtOlOCIC CONOI10N5-
SMALIOW AND INTtRUCDIAIC
AOUirtBS

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     aquifer and  an unobstructed  flow path exists  between
     aquifers.   This condition is most evident at site 9.  The
     shallow aquifer extends down from approximately 615 ft.
     MSL to 600 ft. MSL.

     Ground-water   velocity   in  the  shallow  aquifer  is
     approximately  0.61  feet per  day.   Most  of this  flow
     appears  to   be  captured   by  the   existing  leachate
     collection system.   In the absence  of  the system, the
     shallow aquifer would  tend to  discharge directly  to
     McBride Drain through seepage, leachate seeps or springs.
     Ground-water flow tends to be radial on the  north side of
     the hydraulic divide and south/west  on the  south side as
     shown in Figure 3.

     b.   Intermediate  Aquifer.    The intermediate  aquifer.
     consists of  a lacustrine sand layer residing  atop the
     fine grained  glacial  till  and below the  discontinuous
     lacustrine clay.  The intermediate aquifer is generally
     confined where the overlying silty clay is present, and
     under water  table  conditions (unconfined) where  it  is
     absent. Where the  clay unit is absent, the intermediate
     aquifer receives discharge from the shallow aquifer.  The
     intermediate aquifer extends down from approximately 605
     ft. MSL to 570 ft.  MSL.  Ground-water  velocity  in the
     intermediate aquifer is  approximately 0.051 feet per day.
     Ground-water flow is generally southward toward McBride
     Drain.

     c.   Deep  Aquifer.    The deep aquifer  includes  a sandy
     glacial till  layer  sandwiched between  upper  and lower
     fine-grained till units. It is confined over the entire
     study area and buffered  from the potential  effects of the
     SMDA site  by the intermediate  aquifer and two aquitards.
     The deep aquifer extends from approximately 565 ft. MSL
     to  555 ft.  MSL.    Ground-water  velocity  in the  deep
     aquifer is approximately 0.0041  feet per  day.   Ground-
     water flow is generally  to the southeast at a uniform low
     gradient.

3.   Landfills 9 and 9a

The partially fenced flat landfills are covered by trees and
grasses.  Surface water  drains collect runoff, discharging it
into a  marshy  area in the  southwest corner of site  9, and
directly into McBride Drain.  Erosion  is occurring along the
perimeter of the  landfill where steep, sandy slopes support
sparse vegetation.

The site 9 landfill cover, thin and permeable,   is considered
a primary facilitator of leachate  production and consequent
contamination of the ground water.  Refuse in site  9, up  to 25

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feet thick, is in direct contact with the shallow aquifer and
intermediate aquifer.

The site 9a landfill cover is 2 to 3 feet thick and consists
of a mixture of sand, clay and  silt.  Refuse in site 9a is up
to 20  feet thick.  As in site 9,  most refuse is  in direct
contact with  the shallow aquifer.   Only  a small  portion,
however, is in direct contact with the intermediate aquifer.

4.   Leachate Collection Systems and Slurry Wall

Three leachate collection systems have been installed at the
site.   The most recent system was constructed in  late 1988
along  the  northern  edge of  site  9,   roughly  in  a  line
paralleling 24 Mile  Road,  250 feet south of the property line.
This system includes a slurry wall which extends about 40 feet
through the shallow and intermediate aquifers  and  was keyed
into the till  in  what appears  to be  a  successful  attempt to
prevent the off-site migration of the plume of contamination
to the north.  A subsurface drain is located on the landfill
side of the slurry wall at an elevation  near the bottom of the
shallow aquifer.

A  second   system  was  constructed along the  south-central
portion of site 9a  following  a  leachate outbreak  in 1980.
This system, consisting of a six-inch underdrain which flows
to a holding tank, was installed at an elevation above McBride
Drain, entirely within the waste at site 9a,  and extends for
approximately 2,000 feet along  the southern edge of the site.
A small north-south lateral about 100 feet long exists in the
southeastern part of  site 9a.  A  third system was installed
along the north side of site 9a.

Approximately  200,000 gallons of  leachate per  month  are
removed by tankers  from the collection basins and treated at
an  off-site  licensed wastewater  treatment  facility,  City
Environmental Inc.  in Detroit,  Michigan.

5.   Contamination

     a.   Source

     The  source  of  contamination  from  this site   is  the
     landfilled waste. Much of the landfilled waste, up to 25
     feet  deep,  is  in direct  contact  with the  shallow and
     intermediate aquifer  ground water  which  means that the
     waste is in direct contact with laterally moving ground
     water.   Leachate is  produced in  two  ways:    1)  by the
     horizontal movement  of ground water through  the waste
     and,   2) by the vertical movement  of precipitation down
     through the cap and into the waste mass.  Both means of
     leachate production are present at the site.

-------
The presence of hazardous constituents in the waste mass
is indicated by the chemical composition of the leachate.
Volatile and semi-volatile organic compounds,  inorganic
compounds  and metals  were  detected in  the  leachate
including arsenic, methylene chloride, vinyl  chloride,
and  cadmium.   Table  1  lists the  concentrations  of
contaminants of concern in the leachate.

The  leachate  produced  and released  by the  site  has
contaminated ground water,  and has historically impacted
surface water, and has the  potential to impact sediments
at and near the site.                                ;.

b.   Ground Water

Three  aquifers exist  beneath  the  site:    a  shallow
aquifer, an intermediate aquifer,  and a deep aquifer.

     i.   Shallow Aquifer.  Leachate  from  the landfill
          containing VOCs, SVOCs,  and metals has seeped
          into and contaminated the  shallow aquifer as
          shown in Figure  4.   The contaminants include
          those found in the leachate samples taken from
          the  leachate collection  system.    Table  2
          summarizes the concentrations of contaminants
          found in the shallow aquifer.

     ii.  Intermediate  Aquifer.    Leachate  from  the
          landfills  has  contaminated the  intermediate
          aquifer to a lesser extent.  However, in most
          of  site 9 and  in portions of  site  9a,  the
          shallow aquifer  connects with the intermediate
          aquifer, allowing a free flow of contaminants
          between   the  two   aquifers.       Figure   4
          illustrates the  plume of contamination.  Table
          3    summarizes    the   concentrations    of
          contaminants   found  in  the   intermediate
          aquifer.

     iii. Deep Aquifer.   No evidence  of  contamination
          was  found in the deep, confined aquifer.

Although contaminants were detected in the ground-water
beyond  the  landfill  boundaries  as  indicated by  the
results of the residential well and off-site monitoring
well  sampling, no organic compounds were  detected at
levels   exceeding   Federal   drinking-water   quality
standards.   Some  wells contained levels  of  inorganic
compounds  such as iron or barium that exceeded MCLs.
These compounds occur naturally in local ground-water and
may be related to  natural conditions.  However,  since the
landfill will  continue to produce  leachate, there is a

                      8

-------
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   ISOCONCENTRATION CONTOUR  MAP

-------
                               TABLE »
                    MAXIMUM CONCENTRATIONS DETECTED
                              IN LEACHATE
                  SOUTH HACOMB DISPOSAL AUTHORITY SITE
  Parameter •

  Acetone
  2-Butanone   '  •
  1,2-Dichloroethene
  Methylene Chloride
  Toluene
  Benzyl  Alcohol
  Diethylphthalate
  4-Methylphenol
  Phenol
  Aluminum
  Antimony
;, Arsenic
  Barium
  Cadmium
  Calcium
  Cobalt
  Iron
  Lead
  Magnesium
  Manganese
  Mercury
  Nickel
  Potassium
  Silver
  Sodium
  Zinc
 *Total  Suspended  Sol Ids
 *Total  Dissolved  Solids
 *Total  Alkalinity
 *011  and Grease
 *Chlor1de
 *Sulfate
 *Biolog1cal  Oxygen Demand
 *Chem1cal  Oxygen  Demand
   Value

   2400
  11000
    470
   3100
    530
   1600
   1100
  17000
   4600
    233
    528
     20
    542
    365
3110000
    258
2510000
     68
 500000
  33300
  70001
    238
1450000
      6
1210000
  56500
     13.C
   1130
   7900
   1070
   1470
    860
   2200
  44400
 All  values  except (*)  are presented 1n mlcrograms per Ijter (ug/1)

 * -   mg/1

-------
       Parameter
                        CO..TKMNANT CONCENTRATIONS DETECTED
                       SOUTH   ™THE SHALLOW AQUIFER   ™
                       SOUTH  MACOMB DISPOSAL AUTHORITY SITE
                                    Maximum DetectedValue
      Acetone
      Benzene
      2-Butanone
      Chlorobenzene
      1,2-Dichloroethene (total)
      Ethylbenzene
      Methylene Chloride
      4-Methy1-2-Pentanone
      Toluene
      Total Xylenes
      Bis(2-ethylhexyl)phthalate
     4-Chloro-3-Methylphenol
     1,4-Dichlorobenzene
     4-Hethylphenol
     Phenol
     Aluminum
     Antimony
     Arsenic
     Barium
     Cadmium
     Calcium
    Chromium
    Cobalt
    Copper
    Iron
    Lead
    Magnesium
    Manganese
    Mercury
   Nickel
   Potassium
   Silver
   Sodium
   Vanadium
   Zinc
 *Total  Suspended Sblids
 *Total  Dissolved Solids
 *Total Alkalinity
 *0il and Grease
 *Chloride
 *Sulfate
 *BiologiCefl  Oxygen Demand
 *Chemical Oxygen Demand               fcuuuu

 All  values except (*) are presented in micrograms per liter
 * -  mg/1

 B =  Concentrations are below background in this  area.
NA = Not available
     9300
        8
    11000
       25
      560
       40
     1700
     680
     1400
     260
      32
      14
       8
   15000
    2100
    4150
     837
     79
    886
    491  •
 629000
    136
    187
     86
 459000
   1260
 139000
 13000
     1.4
   443
277000
    43
510000
   273
 6030
   760
 14200
 2780
   732
   710
   60
19000
28000
  An'thmetir

     4135.8
        4.3
     4577.5
       10.0
      211.3.
       15.0
      767.9
      173.8
     601.3
     112.4
      NA
       8.0
       6.0
    3753.8
     528.8
    1750
     219
     20
      B
     125
      B
      B
     52
     30
 124130
    362
      B
   3540
     B
    121
  79807
    12
144400
    71
  3140
    NA
    NA
    NA
    NA
    NA
    NA
   NA
   NA

(ug/i).

-------
                                 TABLE 3
                    CONTAMINANT CONCENTRATIONS DETECTED
                        IN THE INTERMEDIATE AQUIFER
                   SOUTH MACOMB DISPOSAL  AUTHORITY  SITE
   Parameter

   Acetone
   Benzene
   2-Butanone
   Chloroethane
   1,1-Dichloroethane
   1,2-Dichloroethene (total)
   1,2-Dichloropropane
   Ethyl benzene
   Methylene Chloride
   4-Methyl-2-Pentanone
   Toluene
   Total Xylenes
   Vinyl Chloride
   Benzoic Acid
   Bis(2- ethylhexyl)phthalate
   Diethylphthalate
   Isophorone
   2-Methylphenol
   4-Methylphenol
   Pentachlorophenol
   Phenol
   1,2,4-Trichlorobenzene
   Beta-BHC
   Aluminum
   Antimony
   Arsenic
   Barium
   Beryllium
   Cadmium
   Calcium
   Chromium
   Cobalt
   Copper
   Iron
   Lead
   Magnesium
   Manganese
   Mercury
   Nickel
   Potassium
   Selenium
   Silver
   Sodium
.  .Thallium
** Vanadium
   Zinc
Maximum Detected Value    Arithmetic Mean
         1000
           22
         3200
            8
            8
            4
           23
            3
           19
           96
         3700
           11
            8
           53
          210
           60
            8
           20
          370
           50
           19
           12
            0.069
       956000
          256
          219
         3660
           17.6
           31
      4020000
          692
          367
          950
       717000
          481
       909000
        14300
           13
          927
       659000
           28.5
           54
      . 526000
            3.2
          871
       308000
    95.6
     4.1
   537.5
     5.2
     3.0
     2.7
     3.7
     2.5
     3.5
    10.4
   338.8
     3.0
     5.2
    26.8
    NA
     8.4
     8.0
     5.9
    27.8
    27.8
     5.9
     5.4
     0.03
 75440
     B
    35
  1720
     4.5
     B
794690
   162
    91
   263
135760
    74
139690
  4620
     2
   274
 97850
     4.6
     B
157340
     B
   173
  7746

-------
f.
                                        TABLE 3   (Continued)
                                 CONTAMINANT CONCENTRATIONS DETECTED
                                     IN THE INTERMEDIATE AQUIFER
                                 SOUTH  MACOMB  DISPOSAL AUTHORITY SITE
 Parameter                                       Value

*Total Suspended Solids                        116000
*Total Dissolved Solids                          4010
*Total Alkalinity                                2870
*Chloride                                        1070
*Sulfate                                          112
*Biological Oxygen Demand                        1460
*Chemical Oxygen Demand                          1520
ji            All  values  except  (*)  are  presented  in micrograms per liter  (ug/1).
              * -  mg/1
li

0

D
L
I.

-------
          potential for the contaminant plume to move off-site in
          the future as it has in the past.

     c.   Soils

     Surface soil samples were taken  at background  locations,  as
     well as on and off-site.  While no contaminants were detected
     above background  in  the  on- and off-site  surface  soil,  the
     subsurface soil samples on-site were contaminated with a wide
     variety of site-related organic  and inorganic  substances as
     shown in Table 4.

     d.   Surface Water and Sediments.

     While leachate outbreaks have impacted  McBride  Drain in the
     past resulting in  fish kills, leachate and contaminated ground
     water appeared  to be having  little measured effect  on the
     surface  water  and  sediment  of  McBride  Drain,  since  the
     construction of the leachate collection systems and the slurry
     wall, as indicated by surface water and sediment samples taken
     during  the  investigation.    The  landfill  will,   however,
     continue  to  produce  and  potentially  discharge  hazardous
     leachate  into  the marshy  areas and  surface waters,  if  no
     action is taken.   In  this case, measurable adverse effects on
     McBride Drain, and consequently the Clinton River,  may occur
     in the future.
F.   Summary of Site Risks

The  analytical  data  collected  during  the RI  and  the  public
health/environmental  assessment   indicated   the   presence   of
contaminants in various  media at levels that may present a risk to
human health.   Pursuant  to the NCP, a baseline risk assessment was
performed based on present conditions at the site.   The baseline
risk assessment assumes no corrective action will  take place and
that no  site-use restrictions or institutional controls  such as
fencing, ground-water use restrictions or construction restrictions
will be  imposed.   The risk assessment then determines actual or
potential risks or toxic effects the chemical  contaminants at the
site pose  under current  and future land  use  assumptions.   The
baseline risk assessment included the following assumptions:

     The aquifers  contaminated  by the  site   may  be  used as  a
     drinking water source;

     Parts of the site may be used for residential  development;

     Access restrictions such as  fencing of the site will not be
     implemented; and

     No ground-water use restrictions will be  enforced.

-------
  TABLED
                                Groundwater  Residential
                                               Wells
      Acetone
      Benzene
      2-Butanone
      Carbon dijulflde
      Carbon tetrachlorlde
      Chloroethane (c)
      Chloroform
      1.1-Olchloroethant
      1.2-Oichloroethylene
      Ethylbenzene
      2-Hexanone (c)
      Methylen* chloride
      4-Methyl-2-pentanont
      Styrene
      1.1.2.2-Tetrachloroetnane
      Tetrachloroethylene
     Toluene
     I,l.l-Tr1ch1oroethan«
     Tr1chloroethylen«
     Vinyl chlorld*
     Xy'»nes

  Seral-volitiles

     Benzole tcld
     Bls(2-ethylhexyl)phth*laU
     Butyl benzyl pnthalate
    Chloro benzene
    4-Chloro-3-fflethylpbenol (c)
    1.4-Oichlorobenzene
    01»:hylphthalate
    Oi-n-butyl pnthalatt
    Fluorantnene
    Isophoront
    2-Methylphanol
    4-M«thylphefiol
    4-Nltrophenol  (c)
    Pentachlorophenol
    Phenanthrtn*
    Phenol
    Pyrene
    J.2,4-TpIchlorobenzen*
   2.4.5-Trlchloroph«flol

PesiddM/PCfls

   Bata-BHC
   Heptachlor
   PCB-1232
X
X (b)
X (b)
X (a)
X (b)
X (b)
X
J X (b)
x x
X (b)
X X (b)
X (b)
X (b)
. 51.']

Ul]
A
x (b;
x
X

x (b)
x (b)
X
X
X (b)
X
X (b)
X
X
X
X (b)

X
X fM
X (a)
X (b)
                      5!:)
                                    X
                                    X
                                    X
                                  X (b)
          x  (b)
                                    X
                                    X
                                    X

                                    X
                                    X
                                   X
                                   X
                                 x (b)


                                 X (b)
                                   X
                                   X
                                 X (b)


                                 X (b)

                                  X

                                X (b)

                                  X

                                X (b)
                               X(b)
                                                X  r
                                                X
                                                X
                     POOR QUALITY
                          ORIGINAL

-------
 G
 0
r
                                        CHEMICALS o^ PUIINMAI co-*C£s«
                                           SOUTH KACOMB SITE   LO""K"
                                                                                  ym,
                                                                                  MEDIUM
                           Surface   Sediment,   Surface  Subsurface
                            Water




                             X

                             X
                                                           Soil
               Chemical
             Aluminum (c)
             Antimony
           .  Arsenic
             Barium
             Beryllium
             Cadmium
             Calcium (c)
             Chromium
             Cobalt  (c)
            Copper
            Iron  (c)
            Lead  (c)
            Magnesium (c)
            Manganese
            Mercury
            Nickel
            Potass tun (c)
            Selenium
            Silver
            Sodium (c)
            Thallium
           Vanadium
           Zinc
           Cyanide^"
a) Detected In upcradlent or background staples it Jiatlar  levels.
b  Detected In only one suple.
c  No human health toxtclty criteria available for this chealejl.
d] Detected on-ilte only
                             X


                             X



                            X

                            X
                                                                     Soil
 X
 X
 X
 X
 X
 X
 X
 X
 X
 X
 X
X
          Alr     6round*ater
  X
  X
  X
  X
  X
  X
 X
 X
 X
 X
 X
 X
 X
 X
 X
 X
 X
 x •
 X
 X
 X
X
X
                             "esidential
                                Veils
 X

 X




X

X
                                                                               POOR  QUALITY
                                                                                    ORIGINAL

-------
1.   Contaminant Identification

The  medium of  concern for  human  exposures was  identified
primarily  as  ground  water which  has  been  contaminated  by
leachate  from  the landfills.   The contaminants  of concern
selected for non-carcinogenic risk  characterization in ground
water were:

Acetone             2-Butanone          Methylene chloride
1,2-Dichloroethlene 4-Methyl-2-pentanone
4-Methylphenol      Phenol              Toluene
Antimony            Arsenic             Barium
Cadmium             Chromium            Copper            >*•
Manganese           Mercury             Nickel
Selenium            Silver              Thallium
Vanadium            Zinc

The  contaminants  of  concern selected  for  carcinogenic risk
characterization in ground water were:

Vinyl Chloride      Arsenic              Benzene
1,1-Dichloroethane  1,4-Dichlorobenzene  Methylene chloride
1,2-Dichloroethene

Analytical  data gathered  from surface  water  and  sediment
samples  from  McBride  Drain  indicated  no  exceedances  of
constituents compared to background levels  in the creek.  The
risk assessment concluded that the surface water  and sediments
in McBride Drain do not pose a current risk to human health
and the environment.

Analytical data gathered from the  residential  wells sampled
and  monitoring wells  located outside  the  site  boundaries
indicated no exceedances of Federal maximum  contaminant levels
(MCLs) for organic constituents.   Metals that exceeded MCLs
did not exceed background levels.

2.   Exposure Assessment

Potential  exposure to contaminants from this  site  can come
about through the following  potential  pathways or routes of
exposure:

-    Incidental ingestion of ground water by trespassers, site
     workers and residents;

-    Dermal contact  with ground water by site workers and
     residents;

     Inhalation of volatile organic compounds by site workers
     and residents;
                           10

-------
-    Incidental ingestion of surface and subsurface soils by
     trespassers, site workers and residents; and

     Dermal  contact with  surface  and  subsurface  soil  by
     trespassers, site workers and residents.

3.   Risk Characterization

The non-carcinogenic and carcinogenic health risks associated
with each of the pathways and potential  receptors listed above
have been evaluated.   Basic toxicity information used  to
calculate  risk   was  derived  from   the   Integrated  Risk
Information System  (IRIS) and the Health Effects Assessment
Summary Tables (HEAST).

     a.  Non-carcinogenic Health Risks

Reference  doses  (RfDs) have   been  developed  by  EPA  for
indicating the potential  for   adverse  health effects  from
exposure  to  chemicals   exhibiting  non-carcinogenic  effects.
RfDs, which are expressed in units of mg/kg-day, are estimates
of  lifetime   daily  exposure  levels for humans,  including
sensitive individuals.    Estimated intakes  of chemicals from
environmental media  (e.g.,  the amount of a chemical ingested
from contaminated drinking  water)  can be  compared to the RfD.
Rfds are derived from human epidemiological studies or animal
studies to which uncertainty factors have been applied (e.g.,
to account for the  use  of  animal  data  to predict effects on
humans).  These uncertainty factors help  ensure that the RfDs
will  not  underestimate  the  potential  for  adverse  non-
carcinogenic effects to occur.

Potential concern for  non-carcinogenic  effects  of  a  single
contaminant in  a single medium is expressed as  the  hazard
quotient  (HQ)  (or the  ratio  of  the estimated intake derived
from the  contaminant concentration in  a  given medium  to the
contaminant's  reference dose).    By  adding the HQs for all
contaminants within  a medium or across all media to which a
given population may reasonably be exposed, the Hazard Index
(HI) can  be  generated.   The HI provides a useful reference
point  for gauging  the  potential significance  of  multiple
contaminant exposures within a single medium  or across media.
Any Hazard Index value  greater than 1.0  suggests that a non-
carcinogen potentially  presents an unacceptable health risk.

The  following table > indicates  the total  Hazard  Index for
different scenarios involving ingestion  or inhalation of, or
direct contact with, site contaminants.
                           11

-------
     Receptor                                HI

     Worker/Resident                       <1.0
          On-site - surface soils,
          sub-surface soils,
          dust, and VOCs

     Worker/Resident                       <1.0
          Off-site - surface soils,
          sub-surface soils,
          dust, and VOCs

     Worker/Resident                                           •*•
          On-site Ground Water
          Shallow Aquifer                  142.0
          Intermediate Aquifer              15.7
          Deep Aquifer                       1.7

     Resident
          Off-site Ground Water              1.5

The Hazard Index for ground water  exceeds the value of 1.0 for all
ground-water use.   Table  5  provides  an additional  breakdown of
Hazard Indices relating to exposure routes.

          b.   Carcinogenic Health Risks

     Cancer potency  factors  (CPFs)  have been developed  by EPA's
     Carcinogenic Assessment Group for estimating excess lifetime
     cancer  risk   associated  with   exposure  to   potentially
     carcinogenic chemicals.  CPFs, which are expressed in units of
     (mg/kg-day) "1,  are multiplied by  the  estimated intake  of a
     potential carcinogen,  in mg/kg-day, to provide an upper-bound
     estimate of the excess  lifetime cancer risk associated with
     exposure  at that  intake  level.    The term  "upper  bound"
     reflects the conservative  estimate of the  risks  calculated
     from the CPF.   Use of this approach makes  underestimation of
     the  actual cancer  risk highly  unlikely.    Cancer  potency
     factors are derived from the results of human epidemiological
     studies or chronic animal bioassays to which animal-to-human
     extrapolation and uncertainty factors have been applied (e.g. ,
     to account for the use  of  animal  data  to predict  effects on
     humans).

     Excess Lifetime Cancer Risks are determined by multiplying the
     intake  level  with  the  cancer   potency   factor  for  each
     contaminant of concern.  These risks are probabilities that
     are generally expressed in  scientific notation  (e.g. 1 X  10"6
     or  1E-6) .    An excess lifetime  cancer risk  of  1  X  10"6
     indicates that, as  a plausible upper bound, an individual has
     a one in one million chance of developing  cancer as a result
     of  site-related exposure  to a  carcinogen over  a  70-year

                                12

-------
                                  TABLE  5
                   QUANTITATIVE RISK ASSESSMENT SUMMARY
                     FUTURE LAND-USE EXPOSURE  PATHWAYS
                             SOUTH MACOMB  SITE
Exposure                                               Upper-bound    Hazard
Pathway                                              Excess lifetime  Index
                                                       Cancer risk
                                                                      r

Direct contact with surface soils
by construction workers
     On-site saturated soils                               4E-08       7E-03
     On-site unsaturated soils                             1E-07       7E-03
     Off-site saturated soils                              3E-08       7E-03

Inhalation of volatiles by construction workers
     On-site saturated soils                               5E-09       6E-01
     On-site unsaturated soils                             2E-07       9E-02
     Off-site saturated soils                                (a)       2E-03

Inhalation of dust by construction workers
     On-site saturated soils                               3E-07       5E-02
     On-site unsaturated soils                             1E-07       1E-02
     Off-site saturated soils                              1E-07       1E-02

Direct contact with surface soils by future residents      4E-08       6E-05

Use of groundwater by future residents
   Shallow aquifer
     Ingestion (unfiltered inorganics)                     2E-03       142
     Ingestion (filtered inorganics)                       3E-03        29.8
     Inhalation while showering                            6E-07       8E-03
   Intermediate aquifer south
     Ingestion (unfiltered inorganics)                     2E-03        15.7
     Ingestion (filtered inorganics)                       3E-03         7,7
     Inhalation while showering                            3E-09       1E-03
   Intermediate aquifer north
     Ingestion (unfiltered inorganics)                     2E-03         7.7
     Ingestion (filtered inorganics)                       2E-03         5.5
     Inhalation while showering                            6E-08       1E-04
   Deep aquifer
     Ingestion (unfiltered inorganics)                     9E-07        11.9
     Ingestion (filtered inorganics)                       9E-07         1.7
     Inhalation while showering                            3E-09        5E-07

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                                TABLE 5  (Con't)
                      QUANTITATIVE RISK ASSESSMENT SUMMARY
                       FUTURE LAND-USE EXPOSURE PATHWAYS
                               SOUTH MACOMB SITE
Exposure                                               Upper-bound    Hazard
Pathway                                              Excess  lifetime   Index
                                                       Cancer  risk
                                                                       f

Summation across exposure pathways
   Construction workers
     On-site saturated soils                               3E-07        6E-01
     On-site unsaturated soils                             4E-07        1E-02
     Off-site saturated soils                              1E-07        2E-02

   Future residents
     Shallow aquifer (unfiltered inorganics)               2E-03        142
     Shallow aquifer (filtered inorganics)                 3E-03         29.8
     Intermediate aquifer south (unfiltered inorganics)    2E-03         15.7
     Intermediate aquifer south (filtered inorganics)      2E-03          7.7
     Intermediate aquifer north (unfiltered inorganics)    2E-03          7.7
     Intermediate aquifer north (filtered inorganics)      2E-03          5.5
     Deep aquifer (unfiltered inorganics)                  9E-07         11.9
     Deep aquifer (filtered inorganics)                    9E-07          1.7

• •^•^•••••••^^^^^••••^••••••••••••(••••^•^^•••••••••^••••^•••••••••••^•^^^^••B ^^M» • • •» ^ mm <•• ^^^BviB^a
(a)No carcinogens detected.

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                                TABLE 5  (Con't)

                      QUANTITATIVE RISK ASSESSMENT SUMMARY
                       CURRENT LAND-USE EXPOSURE PATHWAYS
                               SOUTH MACOMB SITE
Exposure
Pathway
Direct contact with surface soil by trespassers
Consumption of deer meat
Consumption of fish from McBride Drain
Dermal contact while wading in McBride Drain
Inhalation by trespassers
Inhalation by nearby residents
Upper-bound Hazard
Excess lifetime Index
Cancer risk
i.
2E-08
3E-09
IE-OS
9E-13
1E-06
6E-06
4E-05
3E-10
5E-02
4E-03
1E-03
7E-03
Summation across exposure pathways:
     Trespassers
     Residents
       IE-OS
2E-05 - 3E-05
     5E-02
6E-02 - 1.5
(a)  No inhalation criteria available.
(b)  No carcinogens detected.
(c)  No volatile detected: therefore, no inhalation risk.

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     lifetime under the  specific  exposure conditions at  a  site.
     EPA generally attempts to reduce the excess  lifetime cancer
     risk posed by a Superfund site to a  range of 1E-04 to 1E-06 (1
     in 10,000 to 1 in  1 million),  with an emphasis on the most
     protective end (1E-06)  of the scale.

The following table indicates the Excess Lifetime Cancer Risks for
different scenarios involving irigestion or  inhalation of, or direct
contact with, site contaminants.


     Receptor                   Total Incremental Cancer  Risk
                                                               'r
     Worker/Resident                         3E-07
          On-site - surface  soils,
          sub-surface  soils,
          dust, and VOCs

     Worker/Resident                         1E-06
          Off-site - surface soils,
          sub-surface  soils,
    *     dust, and VOCs

     Worker/Resident
          On-site Ground Water
          Shallow Aquifer                   2E-03
          Intermediate Aquifer              2E-03
          Deep Aquifer                      9E-07

     Resident
          Off-site Ground Water             2E-06

     The excess lifetime  cancer risk for  all reasonable  maximum
     exposure routes  under the residential scenarios exceeds the
     acceptable risk range of 1E-04 to 1E-06.  Table 5 provides an
     additional breakdown of excess  lifetime cancer risk relating
     to exposure routes.

     4.    Environmental  Risks

     Environmental  threats posed by  the  site appear to  be  minimal
     at the present time given the currently operated ground-water
     controls and the resulting  low concentrations of  chemicals
     detected during the investigation in surface soils and  surface
     water.  A preliminary ecological assessment has been performed
     at the  site that indicates no  critical habitats,  endangered
     species  or habitats  of endangered species at or near the site
     are currently  affected  by site  contamination.   Contamination
     of the wetland area and McBride Drain has, however, occurred
     in the  past resulting in fish kills,  and could occur in the
     future if current response actions should be discontinued and
     further  response  actions not  taken.

                               13

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     5.   Risk Summary

     The principal risks at the site are derived from the potential
     ingestion of contaminated ground-water from either the shallow
     or  intermediate  aquifers.   Ingestion of  contaminated water
     from either of these sources results in potential upperbound
     excess lifetime  cancer risks  of  2 X 10"*  and hazard indices
     ranging from 5.5  to 142.  Exposure to contamination in surface
     and  subsurface  soils,   either  through  direct  contact  or
     inhalation of volatile vapors or contaminated dust, results in
     health risks ranging from 1 X 10'6  to  2 X  10'8.

     The potential excess lifetime  cancer  risk posed  by the site
     exceeds the  acceptable risk range of 1 X 10"4   to 1 X 10r6
     principally from the use of contaminated ground water in the
     shallow  and  intermediate  aquifers.     This    represents
     unacceptable potential risks to human health.

     The hazard indices  for humans interacting with the site exceed
     the acceptable hazard index of 1.0, principally from the use
     of contaminated ground water in the shallow and intermediate
     aquifers.    This  represents unacceptable potential  risks  to
     human health.

     Actual or  threatened  releases of  hazardous  substances from
     this site,  if not addressed  by  implementation  of the response
     action selected  by this  Record of  Decision,  may  present  an
     imminent  and  substantial   endangerment  to  public  health,
     welfare,  or  the  environment.   With the site  in  its present
     condition,   the  off-site release  of  contaminants  from  the
     landfills to ground-water, surface water (McBride Drain), and
     surrounding properties (through leachate breakouts) remains a
     distinct possibility.


G.   Environmental Standards not met at the Site

In addition to posing unacceptable risks to receptors, SMDA sites
9 and 9a  do not meet applicable or relevant  and appropriate Federal
or State environmental requirements (ARARs) at this time.

     1.   Ground Water

     Table  6  lists  the representative chemicals  found  in  the
     contaminated ground water plume and the corresponding Federal
     and State preliminary ground-water clean-up criteria which EPA
     believes to be  adequately protective.   The ground  water
     contaminant  plume  contains   concentrations  of  hazardous
     substances which exceed most of these ground-water standards
     and clean-up criteria. '
                                14

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                                                          TABLE  6
                                           Chemicals of Concern  in Ground Water
                                            Concentrations & Cleanup Standards
Ground Water
Contaminant


** CATAGORY CARCINOGENS
Arsenic
1 , 1 -D i ch I broethane
1,2-Dichloropropane
1 , 4 • D i eh I orobenzene
Benzene
Methylene Chloride
Vinyl Chloride
Highest
Observed
Cone, (ppb)


64.7
3.6
5.8
8.0
22.0
1460
5.5
Excess Upper
Lifetime
Cancer Risk


2.0E-03
5.8E-06
7.0E-06
3.4E-06
4.1E-06
2.0E-04
2.3E-04
Hazard
Index



NA
NA
NA
NA
NA
NA
NA
Cancer
Risk
Target
1E-4

3.2
62
83
235
195
2.4
2.4
Cancer
Risk
Target
1E-6

0.032
0.62
0.83
2.35
1.95
0.024
0.024
SOWA
HCL
(Ppb)


50.0

5.0
75.0
5.0
2.0
2.0
Mi Act 307
Type B (ppb)



1.0 (a)*
700
1.0 (a)
5.0 (a),.
1.0 *
5.0
1.0 
** CATAGORY NON CARCINOGENS
Antimony
Arsenic
Barium
Cadmium
Chromium, Total
Chromium I II
Chromium VI
Copper
Manganese
Mercury
Nickel
Selenium
Si Iver
Thallium
Vanadium
Zinc
1 , 2 -D i ch I oroethene
2-Butanone
4-Methyl -2-pentanone
4-Methylphenol
Acetone
Methylene Chloride
Phenol
Toluene
704
64.7
2410
412
282


442
11000
1.3
454
7.7
36.4
3.2
230
11000
412
10800
571
12600
7890
1460
1760
1150
NA
NA
NA
NA
NA


NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
7.3
2.7
2.0
34
2.4


0.5
2.3
0.18
0.95
0.11
0.51
1.9
1.9
2.3
0.86
9.0
0.48
1.0
3.3
1.0
.12 .
.16
NA
NA
NA
NA
NA


NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA


NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
NA
10/5
50.0
1000
5.0
100


1300

2.0
100
50.0
50.0
2/1


70.0




5

1000
3.0*
1.0 (a)*
2000*
4.0*

7000*
2.0 *
1000*
700*
2.0*
100*
20.0 (b)*
0.1 (b)*
0.5*
4.0*
1000*
70.0
400
400
400
500 (b)
5.0
1100 (b)
100 (b)
KEY:  *    If local background is greater,  then use the average local  background.
     (a)   Acceptable method detection limit.
     (b)   Act 307 - Type B criteria for surface water (R299.5713).

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2.   Ground Water Protection Goals and the National Contingen-
     cy Plan

EPA's ground-water protection goal has been set forth in the
NCP as follows:

The national goal of the remedy selection process is to select
remedies  that  are  protective  of  human  health  and  the
environment,  that maintain protection  over time,  and  that
minimize untreated waste.   Title 40 of the  Code  of Federal
Regulations  (40 CFR)  Section 300.430(a)(1)(i)).

The NCP states that EPA expects to return usable ground waters
to their beneficial uses, wherever practicable, within a time
frame that is reasonable given the particular circumstances of
the  site.    Whenever restoration  of ground  waters  is  not
practicable, EPA expects to prevent further migration of the
plume, prevent exposure to  the contaminated ground water, and
evaluate   further   risk   reduction.   (40   CFR   Section
300.430(a)(1)(iii)(F)).

Also, the NCP considers the use of institutional controls to
limit exposures to hazardous substances in the ground water:
EPA expects  to use institutional  controls  such as water use
and deed restrictions to supplement  engineering  controls as
appropriate for short-and long-term management to prevent or
limit  exposure  to  hazardous  substances,  pollutants,  or
contaminants....   The use of institutional controls shall not
substitute for active  response measures as  the  sole remedy
unless  such  response  measures  are  determined   not to  be
practicable	  (40 CFR Section 300.430(a)(1)(iii)(D)).

3.   State of Michigan Ground Water Protection Goals

Michigan Act 307 provides for remedial action, at contaminated
sites within the State, which  "shall be protective of the
public health, safety,  and welfare and the  environment and
natural resources."  Additionally,  all  "...remedial actions
which address the remediation  of  an aquifer shall provide for
removal of the hazardous  substance  or substances  from the
aquifer...."      Michigan  Act  307  also  provides   for  the
determination  of  acceptable  criteria   for   ground-water
remediation at the site.

4.   Clean-up Standards

EPA's ground-water clean-up policy is to attain  MCLs under the
Federal Safe Drinking Water Act (SDWA); however,  if clean-up
to MCLs causes the residual risk levels to exceed the 1 x 10
to 1 x 10"6 risk  range, then the Agency must apply risk-based
clean-up levels to reach the goal of  protectiveness  (1 x  10"6
excess lifetime cancer risk).

                           15

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     Michigan Act 307 Rules contain clean-up criteria which include
     three  different  methods  by  which  clean-up  levels can  be
     determined.  The levels are Type A,  Type B, and Type C.  The
     methodology for Type A clean-up is based on background levels
     or method  detection limits for chemicals of concern.   The
     methodology  for  Type  B   clean-up  uses  standardized  risk
     assumptions  and  exposure  assumptions  to  determine clean-up
     levels  which  will  be  protective  of  human  health,  the
     environment, and the use of the involved resource.
     R. 299.5709, R. 299.5711,  and R..299.5713 provide a thorough
     explanation  on how  to apply the  Type  B  clean-up to  the
     chemicals of concern and calculate  the figures  to the site.
     The  methodology  for Type  C  clean-up reviews  the  actual
     conditions of the site; the uses,  present and future,  of the
     site; a site specific risk assessment;  and cost effectiveness
     analysis.  R. 299.5717  provides a thorough explanation of how
     to apply the Type C clean-up to the chemicals of concern.

     Michigan Act  307,  Type B clean-up  criteria provide for the
     calculation of risk-based clean-up  standards at the 1 x 10'6
     excess  lifetime  cancer risk  level  for  each  carcinogenic
     compound.  These standards are usually  more stringent than the
     corresponding MCLs  or  non-zero Maximum Concentration  Limit
     Goals (MCLGs) .  EPA has determined that Michigan Act  307, Type
     A and B criteria are protective and are applicable or relevant
     and appropriate to the site.

     Table  6 lists the Ground-water Cleanup  Standards  for SMDA
     sites 9 and 9a.


H.   Rationale for Further Action

Actual or  threatened  releases  of hazardous substances  from this
site, if not addressed  by implementation  of the  response  action
selected by  this Record of  Decision, may present  an  imminent and
substantial  endangerment  to  public  health,   welfare,  or  the
environment.  Therefore, based on the findings  in the RI report and
the discussion  above,  a  Feasibility Study  (FS) was  performed  to
develop alternatives to address the  threats at  the site.  The  FS
report documents the risks at the site, site-specific applicable or
relevant and appropriate requirements,  and the requirements  of
CERCLA and the NCP, especially the ground-water protection policy,
in the derivation of remedial alternatives for the SMDA sites 9 and
9a.
I.   Description of Alternatives

The alternatives analyzed for the first operable unit at SMDA sites
9 and 9a are presented below:
                               16

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          Alternative l: No Action

A No Action alternative was  evaluated  to serve as a baseline for
comparison against the other cleanup alternatives.  It assumes that
no  corrective action will  be taken  at the  site  and that  no
restrictions will be  placed  on access  or future use of the site.
There are no costs associated with this alternative.

          Alternative 2: Limited Action

          Capital Cost:       $   427,000
          Annual O&M Costs:      109,000
          Present Worth:       2,192,000                       '*
          Years to Implement:  1 to 2

Alternative 2, illustrated in Figures 5 and 6, includes long-term
monitoring of the ground water, residential wells, surface water,
sediment,  leachate,  and air  at the  site and  surrounding area;
construction of a chain link  fence  around the site; land use and
deed restrictions; and, attachment  of  selected residences to the
municipal water supply.

Long-term  Monitoring;  Long-term  monitoring  of  ground  water,
residential wells, surface water and sediment  of McBride Drain,
leachate, and air will be performed twice a year for a minimum of
30 years at the  approximate locations shown in  Figures  5  and 6.
All samples with the  exception of air samples will be analyzed for
the full Contract  Laboratory Program  (CLP) Target Compound List
(TCL)  and Target Analyte List (TAL)  for both organic and inorganic
contaminants with the exception of pesticides/PCBs.  At the end of
30 years EPA will determine the need for additional monitoring.

Long-term monitoring locations will be determined during remedial
design and will include at a minimum:

Upper Aquifer:  6 points (4 existing locations, 2 new)
Intermediate Aquifer:  16 points (10 existing locations, 6 new)
Deep Aquifer:   5 points (2 existing locations, 3 new)

Additional sampling will include any residential wells still in use
around the site;  surface  water and sediment  from 4 locations in
McBride  Drain;  and  leachate  samples  obtained from all  holding
tanks.   Ambient air monitoring samples will be obtained from the
vicinity of the site  (1 upwind and 3 downwind from each site).

Fence;   A  chainlink  fence will be  constructed  around  the entire
site,  including the southern border, to prevent access to the site.
The fencing will  consist  of  a  minimum six 'foot  high  chain link
perimeter fence topped with three strand barbed wire.   The length
of the fence will be  approximately  13,400 feet,  and include at a
minimum one double, 12 foot wide, swing gate for controlled access.
Warning signs advising that the area is hazardous  will be posted

                                17

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   TJ
08
330
oo
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             •1."
                •I
"Jl   (n)n'"p   •'.    T
•vl      "  •   i    «
                                         ^
                                                                                              ICGOO
                                                                                                  FIGURE  5
                                                                                  AIR ANQ

                                                                                  T1*L wfll SAUPIING LOC*:-.'

-------
08
OO
                                                                                                                                                        BCn«CC» SiftS » *MO 9*
                                                                                                                                            ®
                                                                                                                                            o
                                                                                                                                                      HHC PAIBCO UOMtOPiNC
                                                                                                                                                      . (SM*UOW/h*ltOMCOI*Tt)
                                                                                                                                                FIGURE  6
                                                                                                                                                 SHALLOW. iNICRMCDlATt
                                                                                                                                                 »NO DCCP AOUirtB
                                                                                                                                                 uoNiioniNG WELL LOCATIONS
                                                                                                                                                 ALTOMATIVE 2
                                                                                                                                                 SOUIM UACOW0 OlSPOSAl AUTHORITY ytt
                                                                                                                                                 rs *lfc*l

-------
at 100 foot intervals along the fence and at the gate.

Land Use and Deed Restrictions:  Institutional controls, including
deed  restrictions,  will   be  implemented  to  prohibit  future
development of the landfill (including but  not limited to, on-site
excavations,  construction  and  drilling)   and  to  prohibit  the
installation of drinking water supplies  at  the facility.  The deed
restrictions  regarding future  development of  the  landfill  and
installation  of  drinking  water  supplies  will  be  considered
permanent.

Municipal Water Supply;  Individual residences where consumption of
ground water  from private  wells  exceeds a  risk level of 1 x 10r6
due to contamination derived from the site,  will  be attached to the
municipal water supply.

Review of Site  Conditions;   Site  conditions will  be re-evaluated
every five years.  The reviews will  include  a detailed analysis of
the long-term monitoring data, a temporal and spatial evaluation of
contaminant migration in various media, the progress of any natural
attenuation,  an  assessment of current  residual health  risks,  an
evaluation of the effectiveness  of  the  institutional controls,  a
discussion  that  addresses  any  public comments  or  complaints
received during the  five-year period, and an evaluation relative to
what additional remedial measures,  if any,  should be implemented
based on the reviewed site conditions.

Current Remedial Actions;   Remedial  actions  currently in effect at
the Site (leachate collection systems, leachate removal, and slurry
wall) will be maintained and operated.

          Alternative 3: Ground-water Collection and Treatment

          Capital Cost:      $  5,745,000
          Annual O&M Costs:       224,000
          Present Worth:        9,264,000
          Years to Construct:   2 to 3

Alternative 3  includes a modified  long-term monitoring program,
ground-water collection and on-site  treatment; an extension of the
existing slurry wall, and residential attachment to municipal water
supply.   It  also  includes  the land  use/deed restrictions  and
construction of the  chainlink fence  described under Alternative 2.
Figure 7 illustrates the components of Alternative 3.

Long-term Monitoring Program;   Long-term  monitoring  of  ground
water, residential  wells,  surface water and sediment  of McBride
Drain, leachate,  and air  will  be performed twice  a year  for  a
minimum of 30  years.  All samples with the exception of air samples
will be analyzed for organic and inorganic contaminants on the TCL
and TAL, with the exception of pesticides/PCBs.  At the end of 30
years EPA will determine the need for additional monitoring.

                                18

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                                                                                                                                               mHo not JUBHIAM
                                                                                                                                     SUUP PUUPS AND  txniACTiON «cu.
                                                                                                                                               PUUPS ««ii  IK KIO  «•
                                                                                                                                             HCAOCR nPC AT CLOSCST
                                                                                                                                          UONC ronutnii or OTHU
                                                                                                                                     sit
                                                                                                                                                          it UMTS or
                                                                                                                                                  uuuxvu. lANonu
                                                                                                                                                  KBRIS
                                                                                                                                                          SUUP AND
                                                                                                                                                  (TJUP LOCATXW
                                                                                                                                                  «•
                                                                                                                                                  MAOCII m ro
                                                                                                                                                  TDtATUtNl rAOUTY
McBMDC DRAIN
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tmucMt rnou mtAntMT rAcuiv
TO 'OHO* PATH or 4* DIAWTD)
HCAOCn «Pt THOI CONIWUl TO
MceoiDC DRAM
                                                                                                                              ALTERNATIVE NO. 3 PLAM
                                                                                                                              CBOONOWATER PUMP  AND  TREAT
                                                                                                                              SOUTH lucoui DrsrosAi AUTHOMITT art
                                                                                                                              rs KPOTII

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     1. Ground water

     The  ground-water  monitoring program for Alternative  3  is a
     modified version of the program discussed under Alternative 2.
     The ground-water monitoring program will be designed to detect
     increases or decreases in the chemical concentrations of the
     ground  water at  and adjacent  to the  site.   Ground-water
     monitoring will  include  laboratory analysis  of samples from
     existing monitoring  wells, residential wells  available for
     sampling or  still in use, and new  monitoring wells.   The
     number and placement of  additional monitoring  wells will be
     determined during the pre-design phase and will include at;^,a
     minimum: 3 monitoring wells to  be installed  off-site on the
     east side of the site,  2 north of MW 118 and one south of MW
     118; 4  south  of the site,   adjacent to McBride  Drain;  and 4
     background monitoring wells.   The monitoring wells  will be
     screened in the intermediate aquifer.  An adequate number of
     monitoring wells will be placed to the  north of the site to
     further delineate the extent of the contaminant plume.

     2. Surface Water/Sediment Monitoring of McBride Drain

     Samples  will  be  collected  upstream,   adjacent  to,   and
     downstream of the site,  and analyzed for the same parameters
     as ground-water samples.

     3. Air Monitoring

     Air samples will be obtained from  the vicinity of the site, a
     minimum  of 1  upwind and   3  downwind  from  each site,  and
     analyzed for  volatilized  contaminants.   The monitoring is
     intended to detect increases in the level of VOCs at the site.
     A gas collection  system  may be installed  if air monitoring
     indicates air quality standards are being exceeded due to site
     related contamination.

Ground-water Extraction/Collection System

The ground-water extraction system will consist of, at a minimum 1)
8 extraction wells in the intermediate aquifer along the southern
boundary  of  the site;  and 2)  shallow aquifer  subsurface drains
along the periphery of the waste deposits in both sites 9 and 9a.
Additional extraction wells will be located as necessary to extract
ground-water  contaminants outside  the  site  boundaries.    The
extraction wells and drains will collect  leachate that will then
drain by  gravity  to  a series of strategically  placed collection
sumps from which  it  can be pumped to  the treatment plant.   The
extraction wells will be designed to pump sufficient quantities of
ground water to  capture and extract the entire contaminant plume.
The number of extraction  wells   required and the  estimated total
gallons per minute  (gpm)  necessary to capture  the  contamination
plume(s)   will  be  determined  during the  design  phase and  will

                                19

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require a  pilot test of  the  proposed system.   Extracted ground
water  will be  piped to  the  ground-water  treatment system  for
removal of chemicals to their discharge clean up standards prior to
the discharge  to the McBride Drain.   The  extraction/collection
system will operate  until  the ground-water  cleanup standards are
met.   The  system described in this paragraph may  be modified in
design and will  reflect the results of a predesign investigation
that will further delineate the extent of the contaminated plume.

Ground-water Treatment System

The on-site ground-water treatment system, shown  in Figure 8, will
consist of multiple process options capable of treating an aqueous
waste stream containing  VOCs,  SVOCs, and  inorganic compounds.  Tlie
components of the system and target contaminants are as follows:

   TREATMENT SYSTEMS	TARGET COMPOUNDS	.

     Air stripping                 - most VOCs and some SVOCs

     Granular Activated Carbon     - remaining VOCs and SVOCs

     Oxidation/Precipitation       - inorganic compounds

     Granular Media Filtration     - remaining suspended solids.


The treatment system described above  will be  pilot tested during
remedial design, at which  point it may be modified; its subsequent
performance will be monitored  on a regular basis.  The system will
be  adjusted,   i.e.   installation  of   additional  ground-water
extraction wells and/or increased pumping rates as warranted by the
performance data collected during operation.

Cleanup Standards

Ground water  will be treated until   Federal  Maximum Contaminant
Levels (MCLs)  or non-zero  Maximum  Contaminant Level Goals (MCLGs),
promulgated under the Safe Drinking Water  Act,  and the ground-water
cleanup standards  derived under  Michigan Act 307, Type A  and B
criteria are achieved at the point of  compliance:  the edge of the
landfilled waste.  While the cleanup standards can be met at that
point  soon after  construction  of  the  action  is complete,  the
cleanup standards will not  be met   under  the   site,  and  it is
anticipated that the system will  operate  perpetually.  (See Table
6 for Ground-water Cleanup Standards.)

Effluent from the treatment  plant will  be discharged to McBride
Drain, in compliance with the substantive requirements of a NPDES
discharge permit under Part 21 of Michigan Act 245.
                                20

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•.••OUNDWATER
'..• IRACTION
•;V.TEM-
                                                                              MULTI-MEDIA
                                                                              FILTER
                                                                                     VAPOR TO ATMOSPHERE
                                                                                     OR  FURTHER  TREATMENT
                                                                                             AIR STRIPPER
                                                                                                  r
ACTIVATED
CARBON
                                                                                          AIR

                                                                                      SLUDGE TO  DISPOSAL
       TREATED
       WATER
       DISCHARGE
                                           FILTRATE
      LEGEND:
                 UOUIDS
                 SOUDS
                                                                                          FIGURE  8
                                                                                          GROUNDWATER TREATMENT SCHEMATIC
                                                                                          SOUTH MACOM8 DISPOSAL AUTHORfTY SITE
                                                                                          FS REPORT

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Reactivation of the Ground-water Extraction/Treatment System

If ground-water monitoring indicates that the concentration of one
or  more  of  the  contaminants has  increased  above the  cleanup
standards  after  the  ground-water   extraction system  has  been
completed  or  shut  down,  the ground-water  extraction/treatment
system will be reactivated.

Point of Compliance

The point of compliance for the site will be the waste management
boundaries.
                                                               i,
Management of Treatment Residuals

Treatment  of the contaminated  ground-water will  result in  the
generation of  residual sludge containing heavy metals  and  other
contaminants,  as   well  as  spent  carbon  containing  organic
contaminants.  The  treatment residuals,  which will  be  tested to
determine if they are RCRA hazardous waste, will be disposed of at
an  off-site  RCRA  compliant facility.    RCRA  hazardous  waste
generated will comply with Land Disposal Restrictions.

Slurry Wall Extension

The purpose of the slurry wall extension is to intercept off-site
migration of the  contaminant flow  and redirect  the ground-water
flow toward the collection system.   The existing slurry wall along
the north side of site 9 will be extended to include the east side
of site  9  to its juncture  with  the south boundary,  as shown in
Figure  7.   The  slurry wall, extending  from the  ground  surface
through  both  the   shallow  and  intermediate  aquifers,  will  be
anchored into the underlying  low permeability glacial till; it will
be compatible with the existing structure.

Municipal Water Supply Attachment

Including, but not limited to; all residences currently  on 24 Mile
Road adjacent to the site and within one half mile to the east and
west, all residences on the first half mile of Foss Road,  and all
residences on Card Road between 23 Mile Road and 24 Mile Road, not
currently attached to the municipal water supply, will be attached.
All residences  constructed in the future in  the  described area will
also be attached.   The area  of attachment,  as  shown in Figure 9,
includes  the  extent  of  historical and  potential  ground-water
contamination.
                                21

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,M    ,A    .;o  ~   OUM
          21
 SOURCE: U.S.G.S. 7.5' topographic wp.
 l^ldenburg Quafirenglt Michigan.
 Dated 1968 Photorevised 1973 *nd 1980
 Scale: 1*-2000-.
      LEGEND
                                  MICHIGAN
                                   - ' 'I?
                                      :•<	'—'
                                QUADRANGLE LOCATION

                                  POOR QUALITY
                                     ORIGINAL
       2000
   SCAUE IN FEET

  FIGURE 9
SMDA  SITE MAP
                  «ooo
    	X	X	X	X	X	
    DESIGNATES  BOUNDARIES OF MUNICIPAL WATER ATTACHMENT AREA

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Current Remedial Actions

Remedial  actions  currently  in  effect  at  the  site  (leachate
collection  systems,  leachate  removal,  and  slurry  wall)  will
continue to be maintained  and operated,  and  will be incorporated
into  the  remedial  action  as much  as  is  practical  from  an
engineering standpoint.


J.   Summary of Comparative Analysis of Alternatives

In  accordance  with  the NCP,  the relative  performance of  eadh
alternative is evaluated using the nine criteria (40 CFR 300.430)
(e)  (9)   (iii)),  as  a  basis of  comparison.    This  evaluation
determines the most protective and cost-effective alternative that
will meet the cleanup objectives for the site.   The nine criteria
are as follows:

Threshold Criteria

     1.  Overall Protection of Human Health and the Environment

Overall protection of  human  health  and  the  environment addresses
whether or not a  remedy provides adequate protection and describes
how risks posed by each exposure pathway are eliminated, reduced,
or  controlled   through  treatment,  engineering   controls/   or
institutional controls.

The primary risks at the site are due to contaminated ground water.
Potential routes of exposure  are ingestion, inhalation, and dermal
absorption.  Alternative 3 provides overall protection  of human
health and  the  environment by taking active measures  to prevent
exposure to the  contaminants  at the site.   These active measures
include  collection   and  on-site  treatment  of   leachate   and
contaminated ground water.  The ground water collection/extraction
system and  slurry wall  will  prevent off-site  migration  of  the
contaminant plume  and  direct contaminated ground  water  to  the
treatment system.  Cleanup standards for ground water, see Table 6,
will be met at the waste boundary.

Alternative 1  (No Action) and Alternative 2 (fencing, institutional
controls, and  environmental  monitoring)  do not  provide adequate
protection to human health and the environment from exposure to the
contaminants present in the ground water.  Institutional controls
are often difficult to enforce and do not reduce the risks to the
environment.  Monitoring would provide notice but not prevent the
contaminant plume from migrating off-site, at which time additional
measures would be taken.
                                22

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     2.  Compliance with ARARs

This criterion evaluates whether an alternative meets applicable or
relevant and  appropriate requirements  (ARARs) of other State and
Federal environmental statutes and/or provide grounds for invoking
a waiver.

The  major ground  water  ARARs  include the  requirements  of the
Federal Safe Drinking Water Act, the  State Safe Drinking Water Act
(Act  399),   Act   245  of   1929   (as  amended),   and  the  State
Environmental Response Act  (Act 307).
                                                               '*
Alternative  3 will be designed and  implemented to comply with
ground-water  cleanup  standards at the point of  compliance, the
waste boundaries.  The cleanup  standards  for contaminated ground
water at  the site are Michigan Act  307 Type A  and  B  standards,
which treat each contaminant to the 1 x 10-6 level (or background
or limits of detection),  and Federal standards,  as shown in Table
6.  All effluent discharges from the treatment system will comply
with the substantive requirements of a National Pollution Discharge
Elimination System (NPDES)  permit under the Clean Water Act  (CWA).

RCRA waste generation and  temporary  storage  regulations under 40
CFR Part 262  and Land Disposal Restrictions (LDR or Land Ban) under
40 CFR Part 268,  are applicable to residuals from the ground-water
treatment system if they contain RCRA hazardous waste.   Residuals
will be  tested  for  the  presence  of RCRA hazardous  waste.   If
present, waste will be treated to meet LDRs before being disposed
of at an off-site RCRA compliant treatment facility.

Wetland and flood plain requirements:  construction activities at
the site will be  designed to limit impact on adjacent wetlands and
the McBride Drain  floodplain.   Impacts include  wetland hydrology
changes due to excavation,  drain fields and filling activities.  A
preliminary ecological assessment has been performed.  Additional
studies would be performed during preliminary design.

Alternatives 1 and 2 will not meet requirements for the remediation
of contaminated ground water  of Michigan Act  307 since no active
measures for ground-water remediation would be initiated.

ARARs are discussed  in greater detail  in Section L.2.  Statutory
Determinations.

Primary Balancing Criteria

     3.  Lona-Term Effectiveness and Permanence

This criterion  refers to  the ability of a  remedy to  maintain
reliable protection of human health and the environment over time,
once cleanup goals have been met.


                               23

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Alternative  3  would  construct  a  ground-water  collection  and
treatment system that would operative perpetually,  or until ground-
water  cleanup standards  are  met.   The ground-water  collection
system and slurry wall extension will prevent off-site migration of
the contaminant plume.

Alternative   2   provides  little   long-term   effectiveness  and
permanence as it relies on institutional controls and monitoring to
reduce risks at the site.  Alternatives 1 and 2 provide no response
action and thus no long-term effectiveness.

     4.  Reduction of Toxicity. Mobility, or Volume through
          Treatment                                            ..

This criterion  evaluates  treatment  technology  performance in the
reduction of chemical toxicity, mobility, or volume.

Alternative 3 treats the  contaminants  in the  leachate  and ground
water  in an  on-site water treatment  plant.    Treatment  of  the
contaminants would  result  in a significant reduction of contaminant
toxicity through the treatment  process and satisfy  the statutory
preference for treatment as the principal element of the remedy.

The on-site  ground-water treatment  system consists of  multiple
process  options,  including   air  stripping,  granular  activated
carbon,  oxidation/precipitation,  and granular  media  filtration,
capable of treating an aqueous waste stream  containing VOCs, SVOCs,
and inorganic compounds.   The  treatment process will result in the
generation of  residual  sludge containing heavy metals  and other
contaminants,   as  well   as   spent  carbon   containing  organic
contaminants.  The  treatment residuals  will be tested to determine
if they  are  RCRA characteristic  and,  if so,  will be  treated to
comply with  LDRs before  being disposed of  at an off-site RCRA
compliant facility.

Alternatives 1 and 2 do not use treatment.

     5.  Short-Term Effectiveness

Short-term  effectiveness considers  the  time  to reach  cleanup
objectives and the risks an alternative may pose to site workers,
the community,  and the  environment  during  remedy implementation.
This criterion also considers  the  reliability and effectiveness of
any mitigative measures  taken during  remedy  implementation to
control those short-term risks.

All of the  alternatives,  except Alternative  1,  are  considered
effective  in   the   short  term,   as  certain  aspects   of  the
alternatives, such as institutional controls and monitoring would
be implemented  within a  year.    The construction components of
Alternative 3 Would require 2  to 3 years  to complete.  The ground-
water  collection  and  treatment  system,  however,  may  operate

                                24

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perpetually.

The potential for worker exposure to contaminated materials, dust,
and vapors exists for all alternatives except Alternative 1.  The
potential for exposure increases as the amount of activity at the
waste disposal area increases.  Health  risks to workers would be
minimized with routine use of protective equipment.

Construction  of  the  slurry  wall  in  Alternative  3  involves
excavation of waste and transportation of construction materials.
These  activities  could pose  a  temporary  health risk  to  the
community because of the potential for inhaling wind-blown dust and
increased truck traffic  in the area of  the site.   This potential
would be minimized as much as possible  through good construction
practices and engineering controls.

     6.  Implementability

This  criterion   considers   the   technical   and  administrative
feasibility of a  remedy, including the  availability of materials
and services needed to implement and/or construct the remedy.

No major implementability problems are anticipated for any of the
alternatives.  The technologies included  in each alternative are
readily available and easily implemented.   Alternative  2  would
appear to be the  easiest to implement, since  it would require only
an environmental  monitoring system  and  institutional  controls.
Institutional controls,  which may include  deed  restrictions and
access  agreements are,   however,  often difficult  to obtain and
implement.  Alternative  3  treats  ground water  and would require
pilot studies to  ensure  the proper performance of the collection
and treatment system.

     7.   Cost

Estimated   cost   includes  estimated   capital,   operation  and
maintenance, and present net worth costs.

The estimated costs for remedial  action alternatives, listed  in the
following table,  are order-of-magnitude  estimates with an intended
accuracy range of +50 percent and  -30 percent for the identified
alternative.  The estimated cost of the selected alternative will
be further  refined  in the final design.   Capital  costs  are the
direct  and  indirect  costs  required  to initiate  and  install  a
remedial action.   Annual  operation and  maintenance cost   (O&M)
includes the annual operating cost for a remedial action incurred
and paid on  a yearly basis following implementation  of the remedial
action.   Present  worth analysis provides  a method for evaluating
and comparing  costs  that  occur  over different tijne periods  by
discounting future expenditures  to the present year.
                               25

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Alternative
1
2
3
Table 7
Capital Cost
$ -0-
427,000
5,745,000

O&M Cost
$ -0-
109,000
224,000

Present Worth
$ -0-
2,192,000
9,264,000
Modifying Criteria

     8.  State Acceptance
                                                               '*
                                                               Cf
The State of Michigan concurs with the ROD.

     9.  Community Acceptance

Community acceptance of the preferred alternative is described in
the Responsiveness Summary attached to this  ROD.

K.   Selected Remedy

As provided in CERCLA -and the NCP, and based upon the evaluation of
the RI/FS and the nine criteria,  EPA has selected Alternative 3 as
the method  providing overall  effectiveness  proportional to  its
costs  to adequately  protect  human  health  and  the  environment
against exposures to hazardous substances at SMDA sites 9 and 9a.

The selected remedy, Alternative  3, includes long-term monitoring,
ground-water collection and on-site treatment; an extension of the
existing slurry  wall;  residential attachment to municipal  water
supply,  and  access restrictions.   It requires  2  to 3  years  to
construct.   Alternative 3 is discussed in more detail in Section I.
The components of the selected remedy are as follows:

     1.   Long-term Monitoring

     Long-term  monitoring  of  ground  water,  residential  wells,
     surface water and sediment of McBride Drain,  leachate, and air
     will be  performed  twice a  year  for a  minimum of  30 years.
     With the  exception of air samples,  samples  will  be analyzed
     for all compounds on the TCL and TAL as described in Section
     I.  Air samples will be analyzed for VOCs only.  At the end of
     30  years  EPA  will  determine   the  need   for  additional
     monitoring.

     2.   Ground-water Extraction/Collection System

     Ground-water extraction wells will be installed in
     the intermediate aquifer as  necessary to extract ground-water
     contaminants  associated  with the  site.    Shallow  aquifer
     subsurface drains will be constructed along  the periphery of

                               26

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the waste deposits in both sites 9 and 9a.   The purpose of the
extraction  wells  is  to capture  and  extract  the  entire
contaminant  plume.    The extraction  wells and  drains  will
collect leachate in a series of collection sumps from which it
will  be  transported  to  the on-site  ground-water  treatment
system.

The  extraction/collection  system  will   operate until  the
aquifer ground-water cleanup  standards are achieved  at the
point of compliance:  the edge of the landfilled waste.  While
the  cleanup  standards can be  met at that point soon after
construction of the action is complete, the cleanup standards
will not be met under the site  and it  is anticipated that the
system will operate perpetually.

3.   On-site Ground-water Treatment System

The  on-site  ground-water treatment  system will consist  of
multiple process options capable of  treating an aqueous waste
stream containing VOCs,  SVOCs,  and  inorganic compounds  to
their discharge cleanup  standards prior to discharge  to the
McBride Drain.  The treatment residuals, which will be tested
to determine  if they are Resource Conservation  and Recovery
Act (RCRA)  hazardous waste, will be disposed of at an off-site
RCRA compliant facility.  Any RCRA hazardous waste  generated
will be treated to comply with Land Disposal Restrictions.

4.   Slurry Wall Extension

The  purpose  of  the  slurry wall  extension which will  be
constructed along the east  side of site  9, is  to  intercept
off-site migration  of the contaminant flow and  redirect the
flow toward the collection system.  The slurry wall  extension
will be attached to, and  compatible with, the existing slurry
wall along the north side of site 9.

5.   Municipal Water Supply Attachment

All residences within a one  half mile  radius of the site that
are not currently attached to the municipal water supply will
be attached.

6.   Access Restrictions

     a.   Institutional controls that will be instituted may
          include  deed  restrictions  to   limit  access  and
          prevent  future development of  the landfill,  and
          ground-water use restrictions.

     b.   Permanent fences will be constructed and maintained
          around  the entire site  and treatment systems  to
          prevent exposure to  site  contaminants  and  provide

                          27

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               security for the remedial action equipment.

     7.    Cost Summary

     Capital Cost:      $  5,745,000
     Annual O&M Costs:       224,000
     Present Worth:        9,264,000

     8.    Other Provisions

     Mitigative measures will be taken during remedy construction
     activities to minimize the impacts  of noise, dust, smell, and
     erosion run-off  to the surrounding community  and  environs.
     Fugitive dust emissions will not violate the National Ambient
     Air Quality  Standard  for  particulate matter  smaller that 10
     microns (PM-10).   Potential runoff, silting and sedimentation
     problems from construction will be mitigated to  comply with MI
     Acts including Acts 203 (1979), 346 (1972) and  347 (1972) for
     wetland protection, inland lakes and streams,  and soil erosion
     and sedimentation control, respectively.

The selected remedy will achieve substantial risk reduction through
extraction  of  the  leachate and contaminated  ground water  and
treatment  to health-based  levels.    The ground-water  treatment
operable unit meets the remediation goals for  cleanup of the ground
water outlined in the FS.


L.   Statutory Determinations

The selected remedy must satisfy the requirements of  section 121(a-
e) of CERCLA to:

     1.    Protect human health and the environment;
     2.    Comply with ARARs or justify a waiver;
     3.    Be cost effective;
     4.    Utilize  permanent solutions  and alternative  treatment
          technologies  or  resource recovery technologies  to the
          maximum extent practicable;  and
     5.    Satisfy a preference  for treatment as a principal element
          of the remedy.

The implementation of Alternative 3 at the  SMDA sites  9  and 9a
satisfies the requirements of CERCLA as detailed below:

     1.   Protection of Human Health and the Environment

     Implementation of the selected alternative  will  reduce and
     control potential risks to.human health posed by exposure to
     contaminated  ground  water.    Extraction  and  treatment  of
     contaminated  ground  water  to  meet  ground-water  cleanup
     standards will reduce the potential excess  lifetime cancer

                                28

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risk due to  ingestion  of  contaminated ground water from the
unacceptable  risks  currently posed  (e.g.,  2.0  x 10'3  )  by
ground water contaminants to a maximum  risk for individual
carcinogenic  chemicals of approximately  1  x 10~*.   As above,
assuming that all carcinogens were only treated to the 1  x 10"6
level, the maximum cumulative risk would  be approximately 1 x
10"5, which is an acceptable level.  The Hazard Index would be
reduced to 1.0,  which is also an acceptable  level.  Extracting
ground water  in the vicinity of the landfills will lower the
water table of the shallow and intermediate aquifers to below
the  level of the landfilled  waste  to  the maximum extent
practicable,  thus minimizing the production of  leachate by
ground water  flowing laterally through the waste.         \

Access  restrictions   will  prevent  direct  contact  with
contaminated  ground  water until  the ground-water  cleanup
standards  are met.   The  selected  remedy  also  protects the
environment  by  reducing  the potential  risks posed  by  site
chemicals discharging to the surface water  (McBride Drain).

No   unacceptable  short-term  risks   will  be   caused  by
implementation of the remedy. The community and site workers
may be exposed to noise and dust nuisances during installation
of extraction/monitoring wells and construction of the slurry
wall.   Mitigative  measures will  be taken during  remedy
construction  activities to minimize  impacts of construction
upon the  surrounding community.   The chances  of vehicular
accidents may rise due to the projected increase  in the volume
of  truck  traffic in hauling construction  materials  to the
landfill.   Standard safety programs should manage any short-
term risk  of  accidents.  The air stripping treatment component
will be designed  and monitored so as to not result in short-
term risks due to VOC air emissions.  Treatment residuals will
be managed in accordance with LDRs.

2.  Compliance with ARARs

The selected remedy will comply with the Federal and/or State,
where more stringent, applicable or relevant and appropriate
requirements  (ARARs)  listed below:

     a.  Chemical-specific ARARs

     Chemical-specific  ARARs regulate  the  release  to the
     environment  of   specific   substances  having  certain
     chemical   characteristics.     Chemical-specific  ARARs
     typically determine the extent of clean-up at a site.

          i. Ground Water

               Federal ARARs
                           29

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Maximum contaminant levels  (MCLs) and, to a certain
extent, non-zero  maximum contaminant  level  goals
(MCLGs),  the   Federal   drinking-water  standards
promulgated  under  the   Safe  Drinking  Water  Act
(SDWA), are applicable to municipal water supplies
servicing 25 or more people.  At SMDA sites  9 and
9a,  MCLs  and  MCLGs are not  applicable but  are
relevant  and  appropriate  since  the  upper  and
intermediate aquifers are  Class II  sources  which
could potentially be used as  a  source of drinking
water in the area  of concern, and contaminants from
the two aquifers could potentially contaminate the
deep  aquifer  that  is being used  as a  source  of
drinking water. MCLGs are relevant and appropriate
when  the  standard is  set at a  level greater than
zero  (for non-carcinogens),  otherwise,  MCLs  are-
relevant and appropriate.  The point of compliance
for  Federal drinking-water  standards  is  at  the
boundary of the landfilled wastes.

      State ARARs

The  substantive provisions of  Parts  6  and  7  of
Michigan  Act  307  and  Rule  57 of  Act 245  are
applicable or relevant and appropriate to the SMDA
sites 9 and 9a. EPA has  determined that acceptable
standards for ground water clean-up,  that have been
derived  under   Type A and  B  criteria,  would  be
protective in all  the areas  of the plume outside of
the  landfilled waste.    Clean-up   levels  derived
under Type A and B criteria would allow the aquifer
to be restored to its beneficial uses by achieving
the   risk-based   clean-up   standards.     EPA  has
determined  that   these   clean-up   standards  are
protective  of  human health and the environment.
The point of compliance  for these  standards  is at
the boundary of the landfilled waste.

EPA has determined that Type A and B  criteria would
yield ground-water  clean-up standards which would
also  provide  for  the protection of surface  water
quality,  in  turn  protecting human  health  and the
environment.

ii.   Surface Water

      Federal ARARs

Surface water quality standards for  the protection
of  human  health  and  aquatic  life  were developed
under  Section  304  of the  Clean Water  Act  (CWA) .
The Federal Ambient Water  Quality  Criteria  (AWQC)

                30

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          are  nonenforceable  guidelines that  set pollutant
          concentration limits to, protect surface waters that
          are applicable to point source discharges, such as
          from  industrial  or municipal wastewater streams.
          At a Superfund site, the Federal AWQC would not be
          applicable except for pretreatment requirements for
          discharge  of treated  water to  a Publicly  Owned
          Treatment Works (POTW).  CERCLA (section 121(d)(l))
          requires  EPA to  consider whether  AWQC  would  be
          relevant and appropriate under the circumstances of
          a release  or threatened release,  depending on the
          designated  or potential  use of  ground  water  or
          surface water, the environmental media affected by
          the releases or potential releases, and the latest
          information  available.    Since  the  contaminated
          aquifer is a potential  source of drinking water and
          since treated  water may be  discharged  to McBride
          Drain, AWQC adopted for drinking water and AWQC for
          protection  of  freshwater  aquatic  organisms  are
          relevant  and  appropriate  to  the  point  source
          discharge of the treated water into McBride Drain.

               State ARARs

          Portions of the Water Resources Commission Act 245
          (Michigan Act  245)  of  1929,  as  amended, establish
          surface water-quality  standards to  protect  human
          health and the environment.   The State administers
          the  NPDES  program under  Part  21 of Michigan Act
          245;  therefore,  Part   21  of  Act  245  would  be
          applicable to the direct discharge of treated water
          to McBride Drain, to the indirect discharge through
          ground water movement to  a  surface water body,  or
          to a discharge to a POTW.

b.  Location-specific ARARs

Location-specific ARARs are those  requirements that relate to
the geographical position of a site.  These include:

     Federal ARARs

     Executive Order 11988 - Protection of Flood Plains - are
     relevant  and  appropriate for this site.     This  order
     would  require   that   the  leachate   and  ground-water
     treatment system  be  located  above 100-year  flood plain
     elevation and be  protected  from  erosional damage.   The
     landfills are  not currently in  a 100-year  floodplain.
     However, any portion  of  the  remedy that is constructed
     within  the 100-year  flood  plain must be  adequately
     protected against a 100-year flood event.
                           31

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     Section 404 of the CWA regulates the discharge of dredged
     or  fill  material   to waters   of  the  United  States.
     Activities  during  the remedy  may  be regulated  under
     section  404 of  the  CWA;  therefore,  the  substantive
     requirements  of section  404   would  be  relevant  and
     appropriate to the  remedial action at the site.

     Executive Order 11990 -  Protection of Wetlands -  is an
     applicable  requirement to  protect against the loss or
     degradation of wetlands.  Remedial activities may pose a
     threat to  wetland  areas  on the south side of site 9.
     These  threats  include drawdown from the  ground-water
     extraction system as well as siltation and sedimentation
     from  construction.    While  a  preliminary  ecological
     assessment has been performed,  the scope of  the impact
     will be  determined  during design.   Mitigative efforts
     will be applied to  the clean-up if an impact is seen on
     wetlands.

     State ARARs

     The Goemaere-Anderson Wetland Protection  Act 203 of 1979
     (Act 203)  regulates any  activity which  may  take  place
     within wetlands in  the State  of Michigan.  Act 203 is
     relevant and appropriate  to the remedial action at SMDA
     sites 9 and 9a; it  may also require  the replacement of
     adversely impacted  wetlands with comparable resources.

     The Inland Lakes and Streams Act 346 of 1972, as amended,
     regulates inland lakes and  streams in the State. Act 346
     would be applicable to any dredging or filling activity
     on McBride Drain bottomlands.

     The Soil  Erosion and Sedimentation Control Act 347 of
     1972 regulates  earth changes,  including cut  and fill
     activities, which  may contribute to soil erosion  and
     sedimentation of surface waters of the  State.   Act 347
     would apply to any such activity where more than 1 acre
     of land is affected or the regulated action occurs within
     500  feet  of  a  lake or  stream.    Act  347   would  be
     applicable  to  the  ground-water extraction  system  and
     slurry wall construction activities since these actions
     could impact McBride Drain, which is less than 500 feet
     from the landfill area.

c.  Action-specific ARARs

Action-specific ARARs are requirements that define acceptable
treatment and disposal procedures for hazardous substances.

     Federal ARARs
                           32

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Since the SMDA landfills closed prior to November 1980,
RCRA Subtitle C requirements  are  not applicable unless
RCRA-listed  or  characteristic  hazardous  wastes  are
excavated and managed (treated, disposed, or stored), as
defined by  RCRA,  during  cleanup.   RCRA  Land Disposal
Restrictions  (LDR or Land  Ban) would not be applicable
since no  "placement"  of RCRA hazardous waste would be
occurring at this site.

The selected remedy will store and dispose of hazardous
waste  when  the  ground-water  treatment  system is  in
operation.  The contaminated ground water collected wi^Ll
be  stored  at the  treatment  facility  while  awaiting
treatment.   The treatment  processes  will  result in the
generation of residual sludge containing  heavy metals and
other contaminants, as  well as spent carbon containing
organic contaminants.   The RCRA  waste generation and
temporary storage regulations under 40 CFR Part 262 would
then be applicable to that action.  Treatment residuals
will  be  disposed  of  at  an   off-site  RCRA  compliant
facility.

State ARARs

The State  of Michigan administers RCRA within the State.
Under  Hazardous  Waste  Management  Act  64  of  1979,  as
amended, the State regulates the generation, transport,
treatment, storage, and disposal of hazardous waste.  Act
64 would be applicable to the storage/treatment/transport
of  hazardous  residuals  from  the  on-site  treatment
facility.

Parts 4, 9,  and 21 of the Water Resources Commission Act
245  of 1929,  as amended,  establish rules  for  water
quality by  prohibiting injurious  discharges to surface
water.  These rules would  be applicable to the discharge
of treated ground water to McBride Drain.

As  described earlier  in   this  document,  the Michigan
Environmental Response Act  307 of 1982,  as amended (Act
307), provides for the  identification, risk assessment,
and evaluation of contaminated sites within the State.
EPA has determined  that the  substantive  provisions of
Parts 6 and  7 of Act 307 are applicable or relevant and
appropriate  to SMDA sites  9 and 9a.   The Act 307 rules
require that remedial  actions  shall be  protective of
human health, safety,  the environment,  and  the natural
resources of the  State.   To  achieve this  standard of
protectiveness, the Act 307 rules require that  a remedial
action achieves a degree of clean-up  under either Type A
(clean-up to background  levels),  Type  E  (clean-up to
risk-based  levels),  or Type C  (clean-up  to risk-based

                     33

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     levels under site-specific considerations)  criteria.  EPA
     has  determined that  the  Type A  and  B  criteria  are
     appropriate for  the ground-water  operable  unit.   The
     point  of  compliance for clean-up  standards is  at  the
     boundary of the landfilled waste.

3.  Cost-effectiveness

Cost-effectiveness   compares   the   effectiveness   of   an
alternative  in  proportion  to  its  cost  of providing  its
environmental benefits.   Table 7 under Section J.  7. lists the
costs associated with the implementation of the remedies.
                                                          I,
                                                          • if
Alternative  1  (No Action)  has  no cost and  no  benefit.
Alternative  2,  (environmental  monitoring),  is  the  least
expensive  of  the   two   alternatives  that  involve  action.
However,  it does not provide  adequate protection  of human
health   and  the   environment,   meet   ARARs,    or   provide
effectiveness over the long term.

The selected  alternative (Alternative  3)  is considered  the
most  cost-effective way to  achieve remediation  standards
quickly, thereby protecting human  health and the environment,
provide long-term effectiveness, and meet ARARs.

4.    Utilization  of  Permanent  Solutions  and  Alternative
Treatment Technologies or Resource  Recovery  Technologies to
the Maximum Extent Practicable

The selected  remedy represents  the maximum  extent  to which
permanent solutions and treatment technologies can be utilized
in  a  cost-effective  manner  for  this  site.    Of  those
alternatives  that  are protective of human  health  and  the
environment and comply with ARARs,  EPA has determined that the
selected  remedy provides the best  balance  of tradeoffs in
terms of long-term  effectiveness and permanence, reduction in
toxicity  ,  mobility,  or volume achieved  through treatment,
short-term   effectiveness,    implementability,   cost,   and
considering State and community acceptance.

The  NCP  gives  priority  to  long-term  effectiveness  and
reduction of toxicity, mobility or volume at a site, stating
that  these  two  criteria are generally the key decisional
factors to be considered  at Superfund sites once the threshold
criteria  of  protectiveness and  compliance with   ARARs  is
satisfied.   The key criterion used  in  remedy  selection for
SMDA  sites  9  and   9a  was  immediate  reduction  of  toxicity
through  treatment.   Short-term and long-term  effectiveness
were also emphasized in that the selected  remedy will prevent
off-site migration of the contaminant plume.
                           34

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The selected  remedy will significantly reduce  the inherent
hazards posed by the contaminated ground water and leachate by
collecting and treating these contaminants.  The slurry wall
extension and extraction wells will prevent of f-site migration
of the plume  of contamination.   These benefits  are achieved
quickly  and  at a  reasonable cost.   Contaminants  from the
ground water are extracted and permanently addressed through
treatment.

The  State of Michigan  has  (concurred)  with  the  remedy.
Community  acceptance  is addressed   in  the  responsiveness
summary attached to the ROD.
                                                          >*
5.  Preference for Treatment as a Principal Element       ""

The selected remedy for the  first operable unit satisfies the
statutory preference  for treatment  as a principal element
through  treatment  of the contaminants  in the  leachate and
ground  water in  an on-site  ground-water treatment  plant.
Treatment of  the contaminants would  result  in  a significant
reduction  of  contaminant  toxicity   through  the  treatment
process.    Residuals  generated  by  the  multiple  process
treatment  system,  which   could  include   residual  sludge
containing heavy metals  and spent  carbon  containing organic
contaminants, will  be treated  if  necessary to  comply with
LDRs, before being disposed of at an off-site RCRA compliant
facility.
                           35

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                      RESPONSIVENESS SUMMARY
This  Responsiveness  Summary  has  been  prepared  to  meet  the
requirements  of  Sections  113(k)(2)(B)(iv)  and  117(b)  of  the
Comprehensive Environmental Response, Compensation,  and Liability
Act  of  1980,  as  amended by   the  Superfund  Amendments  and
Reauthorization Act of  1986 (CERCLA),  which requires the United
States Environmental Protection Agency (EPA)  to respond "...to each
of the significant comments, criticisms, and new data submitted in
written or  oral presentations" on  a proposed plan  for remedial
action.  This Responsiveness Summary addresses concerns expressed.
by the public and the potentially responsible parties  (PRPs) in the
written and  oral comments  received  by  EPA regarding  the proposed
remedy for  the South Macomb Disposal  Authority  (SMDA)  Landfill
site.

A.        OVERVIEW

     I.   BACKGROUND/PROPOSED PLAN

          The 159-acre  SMDA site,  located 30 miles  northeast of
          Detroit  in  Macomb  County,  Michigan,  consists of  two
          adjacent former municipal  landfills, sites 9 and  9a.  The
          159-acre   landfill   is   located   in   a   generally
          rural/agricultural area.   The  Remedial  Investigation
          identified  two  areas  of  concern at  the  site:    the
          contaminated ground water under  the site, and the source
          of the contamination,  the landfill contents.

          The remedial  alternative selected  for  the  SMDA  site,
          Alternative 3,  is an  operable unit that  addresses  the
          contaminated  ground water.    An  operable  unit  is  a
          discrete action that comprises an incremental step toward
          the  final  remedy; it  is  an  integral  part of a  more
          comprehensive  action  that will be  taken at  the  site.
          This  operable unit addresses  the contaminated ground
          water at the site. The nature of a second operable unit
          to address the landfill contents will be assessed during
          the performance of the first operable unit.   The Proposed
          Plan for remedial action included the following:

          •    Extraction   and   treatment  of  the   groundwater
               contaminant  plume,  with discharge of  the  treated
               water to adjacent McBride Drain;

          •    Construction of a slurry wall;

          •    Environmental monitoring; and

          •    Connection   of  nearby  residents  to  the  local
               municipal water supply.

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     II.  PUBLIC COMMENT PERIOD

          A public comment period was held from May 1, 1991 to June
          6, 1991, to allow interested parties to comment  on the
          proposed plan,  in accordance with Section 117 of CERCLA.
          On May 6, 1991, a  public meeting was held  at the Senior
          Activities Center  in Mt.  Clemens,  Michigan at which EPA
          presented the  proposed plan,  answered questions,  and
          accepted comments  from the public.  During the comment
          period, EPA received approximately 3 written comments and
          1 verbal comment concerning the Proposed Plan.

B.        COMMUNITY INVOLVEMENT                                k

          The level of public interest regarding the site has been
          high since the controversial siting of site  9 in 1968.
          Community concern heightened when leachate outbreaks were
          observed in 1971 and continued on into the 1980s.   The
          leachate outbreaks  resulted in contamination of McBride
          Drain and a  number  of residential  drinking water wells,
          whereupon local residents brought  suit  against SMDA and
    *     the State of Michigan  in 1983.   The State of Michigan
          joined the residents in their suit in  1984.   This case
          was decided in favor of  the plaintiffs in April 1991.
          The  judge's  decision  requires  SMDA  to  undertake  a
          comprehensive   remedial  action plan  at the  site  that
          includes a cap, slurry wall, and ground-water treatment.

          Several key  areas of community concern  in  regard to the
          preferred remedy in  the Proposed Plan are  as follows:

          •    The remedy proposed is not as comprehensive as it
               should  be; i.e., it  should include the slurry wall
               and cap required in  the judge's decision;

          •    The  remedy  should   be  implemented   as  soon  as
               possible,  as  the  community  has already  waited so
               long for  something to be done;  and

          •    The  proposed  construction  activity   may have  an
               adverse  impact  on the community  due  to increased
               traffic,  noise,  and  dust levels in the residential
               areas in  the vicinity  of  the site.    In addition,
               excavation of  the  waste,  and  operation  of  the
               ground-water treatment plant may produce unpleasant
               odors.

          The above concerns have been addressed  in  the following
          section.

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C.        SUMMARY OF SIGNIFICANT COMMENTS

The public comments regarding the SMDA site are organized into the
following categories:

          •    Summary  of  comments  from  the  local  community
               regarding the proposed plan;

          •    Summary  of  comments  from  PRPs  concerning  the
               Remedial Investigation (RI), Feasibility Study (FS)
               and the proposed plan.
                                                               I.
Many  of the  comments  below  have been paraphrased  in order  to
effectively  summarize  them  in  this document.    The reader  is
referred to the public  meeting transcript and the written comments
submitted during  the public  comment, which are  available  in the
Information Repository  located at the Macomb County Public Library.

     I.   SUMMARY OF SIGNIFICANT COMMUNITY COMMENTS

     Most comments received  from  the community  were  taken  at the
     public meeting.  These ranged from support for the preferred
     alternative  (Alternative 3) , as long  as  it is not the final
     remedy and requests  that the EPA stay involved,  to  outrage
     that EPA is not  proposing a  more  comprehensive remedy  or
     subordinating  its process  to  the judge's  ruling in  State
     court.   Several commenters  reiterated concerns  expressed at
     previous  meetings rather  than supporting  or  opposing  any
     particular remedy.  Comments received from the community are
     listed below:

Comment 1

Several  commenters  requested  that cleanup  begin  as  soon  as
possible, asserting that negotiations would delay the start of the
project.

Response 1

EPA is working to ensure  that the project  proceeds as quickly as
possible.    However,  whenever   practicable  and  in  the  public
interest, the EPA  is  required  under  Section  122  of CERCLA  to
negotiate with the PRPs to have them conduct and fund the cleanup
before expending public funds from the Superfund. At  this time, no
condition at the site has been identified which would demonstrate
that  the additional  time  required  for   negotiations  would  be
detrimental to the  public interest, and thus warrant  use  of the
Superfund.  PRPs have indicated interest in  conducting the remedial
design/remedial action (RD/RA)  and  should then be  afforded the
opportunity to negotiate.   However, should negotiations  fail to
achieve an  agreement,  the PRPs  could  be  ordered to conduct the
RD/RA under  Section 106 of  CERCLA  or  the EPA  could conduct the

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 action using the Superfund trust fund.

 Comment 2

 Residents in the immediate vicinity of the site expressed concerns
 about noise, dust, traffic and odors emanating from the excavated
 waste during the construction phase of  the  remedial action.  One
 resident was also concerned about smells from the treatment plant.

 Response 2

 EPA   agrees  that  noise,   dust,   traffic,  and   odor  contrpl
 considerations  are a  high priority  during construction  of the
 remedy and afterwards during operation.  During the design phase of
 the project, EPA will determine  the most effective ways to control
 traffic, dust,  and  construction noise around the site to ensure the
 health  and safety of area residents.   This determination will
 include discussions and meetings with the community prior to any
 actions occurring at  the site as well as  during the activities.  It
 will  require  on-going communication and cooperation  between the
 community and EPA.

 Possible  solutions  may   include   scheduling truck  traffic  for
 specific hours  and limiting  the number of  trucks;  spraying work
 areas and roads with water to keep down dust; use of barriers and
 suppressants to limit dust and odors; as  well as scheduling certain
 types of work such  as excavation of waste for the colder months of
 the year.   The  treatment  plant  itself would not  emit odors as it
 will be enclosed.

 Comment 3

 While some commenters said EPA was "our only hope," others wanted
 to know why they couldn't  say "thanks  for coming but we don't need
 you anymore"  (since  the  judge's decision was  so comprehensive).
 Several commenters  wanted  to know why "EPA doesn't just subordinate
 to the  judge"   or  write  a proposed plan  that "incorporates the
 judge's  remedy."    Two commenters expressed concerns that the
 cleanup plan  selected by EPA  and the action  ordered by Judge
.Balkwill will interfere with each other.

 Response 3

 Once a site is  placed on the National  Priorities  List (NPL) and
 becomes a Superfund site,  the legal processes required by CERCLA
 must be completed.  This includes a determination  of  the nature and
 extent  of  contamination,  evaluation  and  selection  of  cleanup
 alternatives according to  the evaluation criteria discussed  in the
 National Contingency  Plan  (NCP), followed by cleanup of the site
 and eventual delisting  (removal  of the  site from the  NPL) .  Any
 cleanup alternative proposed or endorsed by EPA  must be selected
 after being subjected to specific  evaluation  criteria.    These

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criteria are discussed in Section J of the ROD.

While the  remedy ordered  by  Judge Balkwill  does not appear  to
conflict with the ground-water operable unit selected by EPA,  EPA
recognizes the potential problem and will strive to coordinate with
the appropriate parties to preclude this conflict from occurring.

Comment 4

One  commenter suggested  that EPA  was  "going  for the  cheapest
remedy" and that  EPA was being politically pressured and basing its
decision solely on cost.
                                                               f
Response 4

Cost is only  one of nine  criteria  used during the FS to evaluate
remedies to clean up  an  NPL site.   EPA  selects  the  least costly
remedy only when all  other  evaluation  criteria are met.   In this
case, EPA's proposed  alternative for cleaning up the site is the
most expensive evaluated  for this operable unit.  EPA has not been
"politically  pressured"  into proposing  its  cleanup  plan.   The
proposed plan is  the result of the evaluation criteria discussed in
the FS.

Comment 5

The same commenter wanted to  know  how  EPA "ever  got  past step 1"
(protection of human health and the environment) with a remedy that
does not "get the garbage out of the ground water."

Response 5

EPA's proposed plan for  cleaning  up the  SMDA site  addresses the
greatest threat associated with  the site  - the contaminants in the
ground water.  Section F. of the ROD discusses the results of the
risk assessment.   The  ground-water  operable  unit will reduce site-
related risks to health-based  levels  quickly,  and  is  therefore
protective of human health and the  environment.  A second operable
unit will address the landfilled waste.

Comment 6

The same commenter stated that "midnight dumping" had taken place
in 1968 and 1969.  She wanted  to know what method had been used to
look for "barrels" at  the site and had a scan been done for nuclear
waste.

Response 6

EPA currently has no information concerning  illegal dumping at the
site, but  encourages  individuals  who have such  information  to
contact Dan O'Riordan, EPA's Community Relations Coordinator, at 1-

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 800-621-8431.  EPA has no evidence indicating that drums or nuclear
 waste were disposed of at the site.

 Comment 7

 The  same  commenter  expressed  the  opinion  that,  since the  RI
 contained  the  phrases "lack  sufficient  data,   poorly defined,
 uncertain, assumed,	may and difficult," EPA did not have enough
 information to "come up with any kind of conclusion or any kind of
 a remedy."

 Response 7
                                                               it
 EPA disagrees with the comment.  The purpose of the RI  as stated in
 the National Contingency Plan (NCP) is to assess site conditions to
 the extent necessary to select and implement  a  remedy  in as timely
 a mariner  as possible  in  order to  protect human  health  and the
 environment.   The NCP reflects a bias  for action.  EPA believes
 that, while the remedial  investigation does not provide answers to
 all questions regarding the nature and extent of contamination, it
 was performed to a sufficient level of detail and was sufficiently
 comprehensive  to  determine the need for remedial  action  and to
 evaluate  remedial  action  alternatives.    It  is part  of  the
 scientific method to both identify that which is not known and to
 make assumptions based upon what is known.

 Comment 8

 One commenter stated that $9.3 million is not  acceptable as "a fine
 of judgment."

 Response 8

 A Superfund  cleanup  is not  a  punitive action.   The  cost  of the
 remedial action  is not a  fine or  penalty.    It is  the  cost to
 construct and maintain the cleanup at the SMDA site.   The cost is
 the same whether the PRPs or Superfund pays  for the cleanup.

 Comment 10

 Several residents  present  at the  public meeting  asked how they
 could get their wells tested.

 Response 10

 Residents can call John Hesse, Chief of the  Environmental Health
Assessment  Division,   Michigan  Department  of Public  Health  at
 517/335-8353.

 Comment 11

Residents wanted  to know  who,  under the  proposed plan, would be

                                6

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connected to municipal water.


Response 11 ,

Figure 9 in the ROD shows a map of the area that will be included
in the remedial action.

Comment 12

Two commenters wanted to know "how large the aquifers are under the
landfill  ...  and who  is  at risk," how far the  aquifers  extend
beyond the landfill,  and which way the ground  water  flows  in the
aquifers.

Response 12

The  physical  characteristics of  the  aquifers  are discussed  in
Sections E.2.  and E.5. of the ROD.  The risks associated with the
ground water are discussed in Section F.5. of the ROD.  The purpose
of the  Remedial Investigation was  to  determine  the nature  and
extent of contamination at the site.  The horizontal extent of the
three aquifers  was delineated only  as  far as was necessary  to
ascertain  the  extent of  contamination.    However,  boring  and
monitoring well information indicate that the three aquifers extend
to the  north  of  the site  at  least   2,000  feet and  that  the
intermediate and deep aquifers appear to merge just to the south of
McBride drain.

In addition,  the preferred  plan in the Proposed Plan  requires
continual monitoring  of  the  ground  water  in all  three  aquifers.
Since ground-water  flow is very  slow,  if  any  site  contaminants
should migrate off-site in the future,  they can be detected early
and action taken to prevent  risks to residents in the area still
using wells for drinking water.

Comment 13

Several  residents  expressed  appreciation  and support  for  the
remedial action.

Response 13

Acknowledged.


     II.  SUMMARY OF SIGNIFICANT PRP COMMENTS

The  South Macbmb  Disposal  Authority  (SMDA)   submitted  written
comments on the Proposed Plan  through the Detroit  law firm  of
Dykema  Gossett.   SMDA  determined  that  the   proposed  plan  is
"unwarranted given  the insufficient data  upon which this remedy is

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based and the minimal risk associated with the groundwater."  The
commenter also determined that  EPA has "improperly de-emphasized
cost as a factor  to  be  considered in its selection of a remedy,"
and that Alternative 2  would be a more  appropriate  choice.   The
comments are addressed below:

Comment 1

SMDA states that the data upon which  the  remedy selection is based
is not only  inadequate, but is "seriously  flawed," particularly the
residential well sampling.
                                                               '•
Response 1                                                     ""

EPA disagrees.  EPA does not  believe  more data is required at this
time or  that the  data  is  "seriously flawed."   The  subject  of
additional  data  needs  was   addressed  under Comment/Response  7,
above,  which defined the purpose of the RI.

As to  the  subject of  "flawed data," data gathered  and analyzed
during a remedial  investigation under  the  Superfund  program must
compiy  with  a  Quality  Assurance  Project  Plan  (QAPP)   which
establishes a high standard of data quality.   The data used  to
evaluate alternatives  at the SMDA  site was  subjected to  QAPP
requirements which also demand that data  be validated by EPA's
Central Regional Laboratory.  Data that  did  not meet established
standards were not used in the evaluation.

As  discussed  under  response  7  above,  the   purpose  of  the
investigation was to acquire sufficient information of high quality
to make an expeditious decision concerning the most appropriate way
to clean up the site.   Data  necessary  for  design purposes  of the
remedy, as  opposed to remedy  selection, can be obtained during the
pre-design or remedial  design (RD)  phases.  This  enables  EPA  to
clean  up  sites  as  quickly  as  possible  and  avoid  the  delays
associated with  lengthy and  costly  investigations that are not
specifically necessary for remedy selection.

Comment 2

SMDA states  that  there is no  evidence that ground water from sites
9 and 9a poses a risk to human  health  or to  the environment, and
further,  that there is no significant risk to human health because
one of the  exposure pathways - residential  use of ground water as
a drinking water  source - has been  or will  be  eliminated  at the
appropriate time  as additional residences are or will be connected
to  the municipal  water supply  in  the  event of  future  well
contamination.

Response 2

EPA disagrees with  the commenters'  determination  and believes there

                                8

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is significant  risk from contaminated ground water  at  the site.
The commenter is referred to the risk assessment  section of the ROD
(Section F).

The SMDA  risk assessment seems  to be based  on the fact  that a
municipal water supply has been or  will be made available to local
residents.  However, the fact that residents are being or will be
connected to a municipal water supply does  not  thereby eliminate
the  human   exposure  pathway  from  consideration   and  permit
contamination of the ground  water to continue unchecked.   If no
action is taken at  the  site  and,  in the  future,  contamination is
detected in residential  wells,  it can be assumed that the residents
will have consumed  water from  the  wells  before  the contamination
was detected. This  has  occurred in the past  and it is unacceptable
that it should happen in the future.

In addition,  the NCP  states that  EPA expects  to  return  usable
ground waters to  their beneficial  uses,   wherever  practicable,
within a  time  frame  that   is reasonable  given the  particular
circumstances of the site.  Whenever restoration  of ground water is
not practicable, EPA expects to  prevent  further migration  of the
plume,  prevent  exposure to  the contaminated ground water,  and
evaluate further risk reduction.  The goals of  this remedial action
are to prevent direct contact  with the ground-water contaminants
and off-site migration  of the  contaminant plume.  (40 CFR Section
300.430(a)(1)(iii)(F)).

The NCP also states that the use of institutional  controls shall
not substitute  for  active response  measures  as the  sole  remedy
unless such response measures are determined  not to be practicable.
(40 CFR Section 300.430(a)(1)(iii)(D)).   Active response measures
are practicable in this case.

SMDA also  states that  its  preferred alternative,  Alternative 2
(monitoring only),  would comply  with ARARs.  EPA  has determined
that Alternative 2 would not  meet comply with ARARs and refers the
commenter to the discussion  of ARARs in  Section J.  of  the ROD.
Contaminants in the  ground water  at the site exceed the acceptable
risk range for human health established by EPA, maximum contaminant
levels (MCLs) and Michigan Act 307 standards.

Comment 3

SMDA states that "EPA has improperly de-emphasized cost as a factor
to be considered" in selection of a remedy and questions the cost
effectiveness of the preferred  cleanup alternative in that it "may
be only an interim component of a more comprehensive remedy."

Response 3

EPA disagrees.   The  remedial  alternative  selected  for  the SMDA
site, Alternative 3, is  an operable unit.  The  NCP defines operable

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units as "discrete actions that comprise incremental steps toward
the final remedy."  It is  an integral part of a more comprehensive
action that will be taken  at the site at a later date and, as such,
will not become obsolete or unnecessary until total site cleanup is
achieved  and  the  ground water  beneath the  site  returned  to
beneficial  use.    Most landfill  cleanups   include  some type  of
ground-water remediation and a cap.  EPA considers the ground-water
operable unit to be a complete and final remedy for this phase of
the cleanup.  A second phase will address the landfill contents.

EPA has determined that the greatest risk to human health and the
environment  at the  site  is  ingestion  of  or contact with  the
contaminated ground water.   The cleanup goals for  this operable
unit are to prevent direct contact with the contaminated  ground
water, prevent off-site migration of the contaminants in the ground
water,  and remove  and treat  the .contaminants  to  health-based
levels.  EPA considers the selected alternative (Alternative 3}  to
be  the most  cost-effective way to  achieve the  cleanup  goals
quickly, thereby protecting human health and the  environment.
                               10

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Page No.      1
07/25/91
                                                          ADMINISTRATIVE RECORD INDEX
                                                        REMEDIAL ACTION - UPDATE NO. 1
                                                     SOUTH MACOMB DISPOSAL SUPERFUND SITE
                                                            MACOHB COUNTY, MICHIGAN
FICHE/FRAME  PACES  DATE
                              TITLE
                                                        AUTHOR
                                                                                  RECIPIENT
                                                                                                       DOCUMENT TYPE
                                                                                                                          DOCNUMBER
            1      00/00/00
Comments regarding
residents near the
South Macomb
Disposal Authority
Landfill
Glen Osanock - Citizen
of Macomb Township, MI
                                                                                  Dan O'RJordan, USEPA Correspondence
            2     90/04/21
Summary of Existing
Technical Information
Brenda Tollett,
Dykema Gossett •
(Attorneys for SMDA)
Betty Lavis - USEPA  Correspondence
            2     91/06/03
                               Letter  re:
                               The degree of Liability
                               on South Macomb
                               Disposal Authority
                               (SMOA)
                          Gary Robertson -
                          Citizen of Warren,
                          MI
                          Dan O'Riordan,  USEPA Correspondence
            25    91/06/05
                              Letter  re:
                              Enclosure of  three
                              copies  of comments
                              to  the  EPA's
                              Proposal Plan for
                              Remedial Action for
                              the SMDA Landfill
                              Superfund Site
                          Marguerite Gritenas,
                          Dykema Gossett -
                          (Attorneys for SMDA)
                          Dan O'Riordan,  USEPA Correspondence
            21    90/04/19
Appendix D, Volume II,
Summary of Existing
Technical Information
Available for South
Macomb Disposal
Authority Site 9 I 9A
Contractors for
SMDA
                                                                                  USEPA
                                                                                                       Maps
           30    91/05/24
Meeting Note re:
Original transcript
of the EPA Public
Hearing in regards
to the South Macomb
Disposal Authority
Landfill Superfund
Site on 5/6/91 with
cover letter
Candace Noblett,
Professional Court
Reporting
Dan O'Riordan, USEPA Meeting Notes
            352    87/07/17
Report on Preliminary
Hydrogeotogic
Investigation
Landfills 9 and 9A
Neyer, Tiseo &
Hindo, Ltd.
(Prepared for
SMDA}
                                                                                  USEPA
                                                                                                       Report/Studies

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Page No.      2
07/25/91
                                                          ADMINISTRATIVE RECORD INDEX
                                                        REMEDIAL ACTION - UPDATE NO. 1
                                                     SOUTH MACOMB DISPOSAL SUPERFUND SITE
                                                            MACOMB COUNTY, MICHIGAN
FICHE/FRAME  PAGES DATE
                              HW.E
                                                        AUTHOR
                                                                                  RECIPIENT
                                                                                                       DOCUMENT TYPE      DOCNUM8ER
            107  90/04/19
Appendix D, volume 1
to Summary of Existing
Technical Information
Available for South
Macomb Disposal
Authority Sites 9 and
9A
Contractors for
SHDA
                                                                                  USEPA
                     Report/Studies
            286   90/04/19
Appendices A,B,4C
to Sunroary of
Existing Technical
Information Available
for South Macomb
Disposal Authority
Sites 9 and 9A
Contractors for
SHDA
USEPA
Report/Studies
           57    90/04/19
Summary of Existing
Technical Information
Available for South
Macomb Disposal
Authority Sites 9 and 9A
Contractors for
SMDA
USEPA
Report/Studies
           372   90/08/23
Remedial Investigation
Report • South Macomb
Disposal Authority
Volume I of II
                          CH2MHILL
                                                    USEPA
                                               Report/Studies
           878   90/08/23
Remedial Investigation
Report • South Macomb
Disposal Authority
Volume II of II
CH2MHILL
                          USEPA
                     Report/Studies
           687   90/09/28
Public Comment
Feasibility Study
Report - South Macomb
Disposal Authority
CH2MHILL
USEPA
Report/Studies
           9     91/05/00
Proposed Plan for
Remedial Action
                          USEPA
                     Reports/Studies
           24    91/05/06
South Macomb Disposal
Authority comments to
EPA's proposed plan
for Remedial Action
Ted B. Uahby - SMDA
USEPA
Reports/Studies

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, Page No.
 07/25/91
                                                            ADMINISTRATIVE RECORD INDEX
                                                          REMEDIAL ACTION - UPDATE NO. 1
                                                       SOUTH MACOMB DISPOSAL SUPERFUND SITE
                                                              MACOMB COUNTY, MICHIGAN
 F1CHE/FRAME PAGES DATE
TITLE

for the South Macomb
Authority Superfund
Site
                                                          AUTHOR
                                                                                    RECIPIENT
                                                                                                         DOCUMENT TYPE
DOCNUMBER

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NATURAL RESOURCES COMMISSION
  MARLENE J. FLUHARTY
  GORDON E  GUYER
  O. STEWART MYERS
  RAYMOND POUPORE                           JOHN ENGLER. Governor
                            DEPARTMENT OF NATURAL  RESOURCES
                                         STEVENS T MASON BUILDING
                                            P O BOX 300P8
                                           LANSING. Ml 48909

                                         DELBERT RECTOR. O.reclor
                                                 September 5,  1991
         Mr. Valdas Adamkus,  Regional Administrator
         U.S. Environmental  Protection Agency
         Region 5, 5RA-14
         230 South Dearborn  Street
         Chicago, Illinois 60604

         Dear Mr. Adamkus:

         The Michigan Department  of  Natural  Resources  (MDNR),  on  behalf of the State of
         Michigan, has reviewed the  Record  of Decision (ROD)  signed by you on
         August 13, 1991, for the groundwater operable unit  at the South Macomb
         Disposal Authority  (SMDA) Sites  9  and 9A,  in  Macomb  County,  Michigan.
         Although the declaration in the  ROD states  the contrary,  there was no
         concurrence letter  attached to the signed ROD because we were awaiting
         confirmation that our~~comments on  the last  draft of  the  ROD had been
         addressed.  The State of Michigan  does,  however,  concur  with the remedy
         proposed in the ROD for  the first  operable  unit for  this site since the
         remedial action will  halt further  off-site  migration of  contaminated
         groundwater.

         The remedy selected in that ROD  consists of:

                   leachate  collection,
                   groundwater extraction on-site and  off-site as necessary,
                   on-site treatment of groundwater  and leachate  with discharge to.
                   McBride Drain,
                   extension of the  existing slurry  wall,
                   replacement of water supply wells in the  surrounding area with
                   municipal  water supply,
                   deed restrictions and  fencing  to  provide  for the integrity of the
                   remedy,
                   and long  term  monitoring of groundwater,  including selected
                   residential wells in the area.

         It is the MDNR's judgement  that  although the  selected remedial action for this
         site will meet all  legally  Applicable or Relevant and Appropriate Requirements
         (ARARs) pertinent to the action  to be taken;  it will  not satisfy ARARs for the
         site as a whole.  This remedy will  meet  the Type A  or B  groundwater cleanup
         criteria in Michigan's Act  307 rules at  and beyond  the landfill boundaries;

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Mr. Valdas Adamkus                    -2-                   September 3,  1991
however, the remaining contamination inside the landfill boundaries will
require a Type C final remedy for the site.  The State of Michigan reiterates
the need for further action to address the landfill contents which EPA has
chosen to defer to a second operable unit.  The landfill is, and will continue
to be, a source of contamination to the groundwater beneath the site.  Until a
remedy is implemented which controls this ongoing source of groundwater
contamination, ARARs cannot be met.

Please be aware that there are two very significant court orders currently  in
place regarding this site which may impact aspects of implementation.  The'r
first is a 1989 Consent Decree between Macomb Township and the State of
Michigan which provides for residences in the vicinity of SMOA Sites 9 and  9A
to be attached to municipal water supply in the event that they become
contaminated.  The second is the April  4, 1991 Circuit Court Order requiring
SMOA to remedy the sites.  In addition to groundwater control actions outlined
in this ROD, the court order requires SMDA to construct a multi -media cap on
the site and a slurry wall and leachate collection system entirely around both
of the sites.  We believe that implementation of the court ordered remedy will
meet federal and state ARARs.  Although there is no direct conflict between
these orders and this ROD, it will be imperative for our agencies to work
closely on these actions to avoid duplication of effort and conflict.

It is my hope that in the near future our agencies can successfully select  and
implement a final  remedy for this site which meets federal and state
requirements and considers the existing judicial decisions achieved through
state enforcement actions.
                                        Sincerely,
                                        Frnk
                                        Acting Deputy Director
                                        517-373-7917
cc:   Mr.  Jon Dikinis,  US EPA
     Mr.  Thomas Jacobs, US EPA,  ORC
     Mr.  Douglas Ballotti, US ERA
     Ms.  Betty Lav is,  US EPA •/'
     Mr.  Thomas Emery, Dept. of Attorney General
     Mr.  William Bradford, MDNR
     Ms.  Claudia Kerbawy,  MDNR
     Ms.  Kate Par!ing, MDNR

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