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BASE MAP SOURCE:
U.S. GEOLOGICAL SURVEY
PROJECT NAPP*
MARCH 27.  198«
                                       cmtulM oorftarf*
          ALLUVIUM
          tfc*ort«

          POTTSVILLE FORMATION
GEOLOGICAL FORMATION
SOURCE:
USGS -GEOLOGY OF  THE
CARBOKDALE QUADRANGLE
BULLETIN NO.  48 1925
              jftMUborf|f QortttttvQ oosiont

 COP-1 £^   GENERAL SITE LOCATION A IDENTIFICATION
   APPROXIMATE
 SCALE:  1*  • 2700'
  figure 1-6
1  GEOLOGICAL MAP OP EMMA OU COP AND COC-10 SIR
'  LOCATIONS
  CRAB ORCHAIO NWt
  MAIION, IlLINOtS

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                                                    Crab Orchard National Wildlife Refuge EMMA OV ROD
Sandstone and shale bedrock was encountered in the COC area at depths of 6 to 23 feet.  Thin
coal seams were noted within this bedrock unit.  Sandstone bedrock was encountered at about
25 feet in the COP area.  The sandstones encountered were poorly  sorted, consisting of coarse to
fine sands with silt and clay fines.

Groundwater resources in Williamson County are relatively poor.  Shallow drift wells and cisterns
have been utilized by farmers in this area; however, surface water  is the principal source for
industries and towns.  Deep wells are generally not a good source of water due to high mineral
content (SCS, 1959).  In  general, groundwater flow at die EMMA  OU sites is toward Crab
Orchard Lake.  During Phase I well installations in the COP and Bunker areas, groundwater was
generally encountered at about 18 to 20 feet in the glacial materials that overlie die bedrock.
Groundwater was somewhat more elusive in the COC area, and was generally encountered below
the unconsolidated glacial materials in the sandstone/shale bedrock. Therefore, monitor wells in
the COC area were installed to varying depths in the sandstone/shale bedrock.

The highest groundwater elevations are noted in the vicinity of Sites COC-3 and COC-9.  North
and west of these sites, groundwater flow is toward Crab Orchard Lake. South of diese sites,  the
flow appears to be to the south, possibly toward a section of Crab Orchard Lake that is south and
west of the COC area.  Groundwater contours in die COC area are shown on Figure 1-7.
                      •
Water level  elevations indicate that flow in the COP area is generally northward toward Crab
Orchard Lake, although an apparent groundwater high in die immediate area of Sites COP-3 and
COP-4 results in a local pattern that indicates influence from Little Wolf Creek to the east and an
unnamed drainage to die west. Groundwater contours in die COP  area are shown on Figure 1-8.

Specific site conditions indicate that die EMMA OU shallow groundwater meets die ty-hni^i
definition of a Class I groundwater classificati  « pursuant to 35 Illinois Administrative Code Part
620 (35 IAC Part 620), Section 620.210(a).  Slug tests conducted at die EMMA OU sites during
die RI showed dial die hydraulic conductivity is greater dian 1x10** centimeters per second
(cm/sec). Therefore, die EMMA OU shallow groundwater meets die  definition of Class I
groundwater.
 cnbofd)~t6/rod-«A>4/19/96                          9   •             Environmental Science A Engineering. Inc.

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CONTOUR PATTERNS. JULY 1993

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         420	
                                                          42S
 0   500' 1000'
SCALE: 1* - 1000'
Pliur* 1*6
CRDUNDWATER CONTOUR PATTERNS. JULY  1983
COP AREA
CRAB ORCHARD NWR
MARION. ILLINOIS
ESE
Environment*]
Science &
Engineering, Inc.

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                                                   Crab Orchard National WZUgCr Kefiige EMMA OUKOD
                 2.0  Site History and Enforcement Activities

The eastern portion of the refuge was transferred to the War Department for construction of die
former Illinois Ordnance Plant (IOP), also known as the Crab Orchard Ordnance Plant.  The IOP
was constructed in 1941 for the U.S. Army as part of its National Defense Program. The major
activity conducted at the IOP consisted of trinitrotoluene (TNT) melt-pour operations. Various
munitions and munitions items, including 500-pound bombs, anti-tank mines, and 155 millimeter
(mm) shells, were filled at the former plant The IOP also contained an ammonium nitrate
production unit as well as storage and shipping areas, a shop, and maintenance area. Water for
plant operations was obtained from Crab Orchard Lake and was treated hi an on-site water
treatment plant.  The former ordnance plant maintained a complete domestic sewer system and
treatment plant.

The IOP was closed in 1945, shortly after die end of World War n.  The plant was transferred to
the War Assets Administration (WAA) for disposition.  The plant was reportedly decontaminated
in accordance with military specifications in force at the time, and a portion was leased to private
industrial tenants. Electrical equipment containing polychlorinated biphenyls (PCBs), boats,
corrugated boxes, explosives, and plated metal parts are among the products that have been
manufactured on the refuge. Accountability for the property was  transferred to die USDOI  in
1947.  The USFWS, an agency of USDOI, continues to administer the refuge.

The Crab Orchard NWR was proposed for inclusion on the NPL in 1984 and included as final on
the NPL as published in the July 22, 1987 Federal Register (52 FR 27620).   The refuge is
currently divided into five OUs which include the EMMA OU.

As part of me Formerly Used Defense Sites (FUDS) Program, an Inventory Project Report  for
the refuge was initiated by the U.S. Army Corps of Engineers (USAGE) Chicago Dist ict hi
1986.  Site surveys were conducted and limited to areas believed to be associated with the former
ordnance plant (me EMMA OU)- Based upon the findings of this Inventory Project Report, a
Confirmation Study was conducted ar the direction of the USACE-Omaha District.  The
Confirmation Study Report was completed by Woodward Clyde Consultants (WCQ in April 1988
(WCC, 1988).

The  Confirmation Study focused on 14 sites apparently  associated with the IOP.  Activities
conducted as part of the Confirmation Study included magnetometer surveys, surface and
subsurface soil sampling and analysis, groundwater monitoring well installation, groundwater
sampling and analysis, and surface water and sediment sampling.  The results of the
magnetometer surveys indicated the presence of buried ferrous materials at eight sites.  Results of
some of die samples indicated the presence of munitions related compounds.
cnbordi-rffaxl-A/M/19/96                         12               Eminmmaual Science A Engineering, he.

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                                                   Crab Orchard National Wildlife Refuge EMMA OU ROD
The IS EMMA OU sites consist of the 14 Confirmation Study sites (COG and COP areas) plus
the Bunker 1-3 Site [referred to as Site 19 from the 1988 Remedial Investigation (RI) conducted at
the PCB and MA OUs]. An RI was conducted at the EMMA OU which included a Baseline Risk
Assessment (BRA). Phase I of the RI field investigation involved the excavation of 40 test pits;
die installation and sampling of 14 monitoring wells; the collection of samples from 12 previously
existing monitoring wells; and the drilling and sampling of 10 soil borings. Samples were
analyzed for volatile organic compounds (VOCs), base/neutral acid extractable compounds
(BNAs), nitroaromatic compounds, metals, and total petroleum hydrocarbons. The Phase I field
work was conducted from mid-August to mid-October 1991.

The Phase n RI field investigation was conducted in June, July, and September of  1993 and
focused on 8 of the IS EMMA OU sites based on data garnered in the Phase  I investigation.  A
separate field effort was conducted in October and December 1993 based on the results of a
Preliminary Ecological Risk Assessment. The Phase H investigation involved the collection of
surface soil, surface water, and sediment samples; drilling and sampling of soil borings; and the
installation and sampling of two monitoring wells.  Groundwater samples were  also collected from
all 26 previously existing monitoring wells. Small mammal trapping was conducted at Site
COC-9 to evaluate potential ecological effects. Surface water samples were collected for aquatic
toxicity testing from Site COC-6 to assess potential effects on aquatic species.  Analyses
performed on collected samples included metals, nitroaromatic compounds, VOCs, and BNAs.

The RI was completed  in September 1994. A Feasibility Study (FS) was performed for the
15 EMMA OU sites based on the findings of the RI and the BRA.  The FS evaluated seven
remedial alternatives and was completed in September 199S.  A Proposed Plan was developed and
submitted for public comment in September 1995.

Currently, Crab Orchard Lake provides sport fishermen u.± largemouth bass, catfish, sunfish,
and crappie.  It was used as a drinking water source for the refuge and Marion Federal
Penitentiary until 1993 when the water treatment plant was closed.  Water for the refuge and the
penitentiary is currently supplied by the Herrin municipal system.
 crabofch-i6/rod-«/04/l9/96                         13               Environmental Science A Engateermg. Inc.

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                                                   Crab Orchard National WiUlife Kffiige EMMA OU HOD
                  3.0 Highlights of Community Participation


The RI and BRA Reports for the EMMA OU were released to the public in November 1994.
These two document are available to the public as part of the Administrative Record and in the
information repositories maintained at the following locations.
       Marion Carnegie Public Library            (618) 993-5935
       206 South Market Street
       Marion, IL 62959
       Operating Hours — Monday-Friday 9:00 a.m. to 8:30 p.m.  Central Standard Time (CST)

       Carbondale Public Library                 (618) 457-0354
       405 West Main Street
       Carbondale, IL 62901
       Operating Hours — Monday-Thursday 9:00 a.m. to 8:00 p.m. CST,
       Friday-Sunday 9:00 a.m. to 5:00 p.m. CST

       Crab Orchard National Wildlife Refuge      Contact: Leanne Moore
       RR 3 Box 328                            (618) 997-5491
       Marion, IL 62959
       Operating Hours — Monday-Friday 7:00 a.m. to 4:30 p.m. CST

       Morris Library                           Contact:
       Southern Illinois University                (618) 453-1455
       Carbondale, IL 62901
       Operating Hours — Monday-Thursday 8:00 a.m. to 11:00 p.m. CST.
       Friday 8:00 a.m. to 9:00 p.m.  CST, Saturday. 10:00 a.m. to 6:00 p.m. CST.
       Sunday 1:00 p.m. to 11:00 p.m. CST

       Department of Justice                     Contact: Legal Office
       Marion Federal Penitentiary               (618) 964-1441
       Bureau of Prisons
       RR 5, Little Grassy Road
       Marion, IL 62959
       Documents Available — Monday-Friday 7:30 a.m. to 4:00 p.m. CST


The notice of public availability for these two documents was published in the following four
newspapers:  Southern Illinoisan, Daily Egyptian, Marion Daily, and St. Louis Post Dispatch. In
addition, an availability session and public meeting was held on November 1, 1994 at the refuge
visitors center. At this meeting, representatives from the USFWS,  USACE, Illinois
Environmental Protection Agency (IEPA), and U.S. Environmental Protection Agency (USEPA)
addressed questions about the RI and BRA.


The FS and the Proposed Remedial Action Plan (PP) were released to the public in September
 1995. These two documents are also available in the Administrative Record located in the
information repositories listed above. The notice of availability of these documents was published
in the same four newspapers listed above in  September 1995. An initial public comment period


cnbotdi-c6/rod-a/04/l9/96                         14               Environmental Science A Engineering./IK.

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                                                   Crab Orchard National Wildlife Refuge EHMA OU ROD
was held between September 29, 1995 and October 30,  1995.  The public comment period was
advertised in the four newspapers listed above on September 15, 1995.  At the request of the
public, the comment period was extended by 30 days to November 29,  1995.  An announcement
of the extended public comment period was also placed  in the same four newspapers on
November 2, November 6, November 1, and November 3, 1995, respectively. In addition, a
public availability session and meeting was held on October 19, 1995 at the refuge visitors center.
At this meeting, representatives from the USFWS, USAGE, USEPA, and IEPA addressed
questions and received comments about the remedial alternatives under consideration. A response
to the comments received during the public comment period is included in the Responsiveness
Summary, which is Appendix A of this Record of Decision (ROD).
 c«boccfc-.6/rod-«/04/19/96                          15               Emimmtauul Sdfnte A Enga>t€fng. Inc.

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                                                   Crab Orchard National Wdlife Refitge EMMA OU ROD
                  4.0  Scope and Role of the Response Action

The Crab Orchard NWR is currently divided into five separate operable units. The OUs are the
PCB OU, MA OU, EMMA OU, MISCA OU, and Water Tower OU. Remedies have already
been selected and implementation begun at the MA OU and PCB OU. The Water Tower OU was
remediated as part of a removal action.

This ROD addresses the final remedy for each EMMA OU site except Site COC-4 which requires
further evaluation.  Remedial action was determined to be  necessary at Sites COC-3 and COP-4,
while no further action is required at the remaining 12 sites. Alternative 3A, described in
Section 8.0, is the selected remedial alternative to be implemented at Sites COC-3 and COP-4.
The remedial alternative selected includes:
       •    Excavation and offsite treatment and disposal of soils containing levels of
            nitroaromatic compounds greater than 100,000 mg/kg (or 10 percent) and lead above
            450 mg/kg for treatment at an offsite incinerator;
       •    Additional removal of RDX/HMX contaminated soil at Site COP-4 to a depth of two
            feet below grade within the existing fenced area.  Disposal of excavated soils at an
            offsite permitted special waste landfill;
       •    Sampling to ensure that remaining affected soils p.e., soils with contaminants above
            remediation goals. Remediation goals have been set at die practical quantitation limit
            (PQL) for nitroaromatic compounds and 450 mg/kg for lead. Refer to the discussion
            on remediation goals in Section 10.2] at Sites COC-3 and COP-4 do not exhibit the
            characteristics of a RCRA hazardous waste for lead and 2,4-DNT;
       •    Backfill excavated areas to shape the base of the covers;
       •    Placing 24-inch soil covers over the remaining affected soils at  Sites COC-3 and
            COP-4;
       •    Long-term maintenance of the soil covers for  a p ~ iod of up to  30 years;
       •    Implementation of land use controls at Sites COC-3 and COP-4; and
       •    Groundwater monitoring.

The land use controls  to be implemented at Sites COC-3 and COP-4 include restrictions of the
following activities: groundwater well installation; subgrade activities; and pond creation within
the perimeter of the soil covers on Sites COC-3 and COP-4.

The studies undertaken at the EMMA OU have identified potential human and ecological risks
associated with nitroaromatic compounds and metals,  specifically lead, in soil at Sites COC -3 and
COP-4. The remedial objective for the EMMA OU is to minimize potential human health and
ecological risks associated with the direct contact of affected surface soil at Sites COC-3 and
COP-4. The overall response strategy consistent with CERCLA is to restrict the ability of
 cnboreh-*6/rod-«A>4/l9/96                          16               Environmental Science A Engineering. Inc.

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                                                     Crab Orchard National Wildlife Refuge EMMA OU ROD
humans and animals to contact nitroaromatic compounds and lead in soils at Sites COC-3 and
COP-4, while monitoring the groundwater at Sites COC-3 and COP-4 for contaminants over time.
c«bOfeh-f6/rod-./04/l9/96                          \ ^

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                                                    Crab Orchard National WildBfe Refuge EMMA OV ROD
                   5.0  Documentation of Significant Changes

The preferred remedial alternative presented in the Final FS Report was Alternative 3A.
However, comments were received from die USFWS on the draft FS Report expressing concern
that each of the alternatives studied required nearly consistent levels of institutional controls and
perpetual maintenance. Therefore, during preparation of the Proposed Plan, USAGE evaluated a
modified version of Alternative 4 that was intended to produce a site less dependant of engineered
barriers and institutional controls. In the modified version of Alternative 4, the removal of
non-reactive contaminated soil was increased from approximately 2 feet below existing grade to
approximately 5 feet below grade.  The contaminated soil would be disposed of in a special waste
landfill as described in the FS Report. The contaminated soil would be replaced with clean soil.
The Proposed Plan identified Alternative 4 as the preferred remedial alternative.

Upon further consideration, the USAGE reevaluated  Alternative 4 as the preferred alternative.
Alternative 4 was considered in response to a USFWS concern for the well-being of burrowing
animals that may be present at the sites.  Upon further consideration of the cost differences,
USAGE could not justify the increased cost of excavating to a depth of 5 feet based upon a
speculative risk to an animal that was not identified as a species of concern in the RI and was
screened out in the BRA.  Also, groundwater monitoring would still be required under
Alternative 4 because soils with contaminants above  remediation goals would remain on site.

There are some differences between the description of alternatives presented in the FS Report, the
Proposed Plan, and this ROD. These differences resulted from refinements in assumptions made
for the alternatives, and from correction of calculation errors  discovered in the cost tables.  These
differences are summarized as follows:

        •   Alternatives as presented in the FS Report assumed that a removal action removing
            the soils containing nitroaromatic compounds at levels exceeding 100,000 mg/kg and
            lead  above 450 mg/kg would be conducted prior to implementing the selected
            remedy. In both the Proposed Plan and this ROD, the removal action  is included as
            a key remedial action item in the alternatives presented, with the exception of the No
            Action alternative.
        •   Alternative 3A as described  in this ROD includes the excavation, removal, and offsite
            disposal of affected soils to a depth of two feet below grade within the existing
            fenced area at Site COP-4. This minimal additional excavation at Site COP-4 was
            not included  in the description of Alternative 3A in the FS Report or Proposed Plan.
            It is  anticipated that removal of soils within this area will reduce the concentration of
            nitroaromatic contaminants remaining at the site to a level approximating that at
            Site COC-3 and is intended to allow for similar management of residual risks
            between Sites COC-3 and COP-4.
 cnbocch-«6/rod-*A04/19/96                          |g               Eitvironmaaal Xcuncr 4 Engineering, Inc.

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                                                    Crab Orchard National Wildlife Refuge EMMA OU ROD
           Alternative 3A, as presented in the FS Report and Proposed Plan, included fencing.
           Alternative 3A presented in this ROD does not include fencing.  Fencing is not
           required since installation of the soil cover under Alternative 3A meets the remedial
           objective of preventing direct contact with affected soils at Sites COC-3 and COP-4.
           Fencing is not required to maintain the integrity of die soil cover.
           Alternative 4, as described in both the Proposed Plan and this ROD, includes the
           excavation, removal and offsite disposal of the remaining affected soils at both
           Sites COC-3 and COP-4 to a depth of 5 feet below grade. Under Alternative 4
           described in the FS Report the depth of excavation was limited to 2 feet below grade.
           In addition, Alternative 4 described in the FS Report included fencing.  Alternative 4
           described in both the Proposed Plan and mis ROD does not include fencing.
           Alternative SA, as described in bom the Proposed Plan and mis ROD, includes me
           excavation and onshe treatment by composting of the affected soils at bom
           Sites COC-3 and COP-4 to a depth of 5 feet below grade. In Alternative SA
           described in the FS Report, the depth of excavation was limited to 2 feet below
           grade.
           The costs in the FS Report are significantly different in the ROD. This is due to the
           cost of offsite incineration of the soils with levels greater  than 100.000 mg/kg of
           nitroaromatics, revised groundwater monitoring assumptions, and revised operations
           and maintenance costs.
cnbocch-i6/rod-a/M/l9/96                          19                Environmental Science A Eitgoutring. lite.

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                                                    Crab Orchard National Wildlife Refuge EMMA OU ROD
                      6.0  Summary of Site Characteristics

During the RI, various media were sampled at the COC, COP, and Bunker 1-3 sites including
soil samples collected from test pits, soil borings, and monitoring well borings; groundwater
samples; sediment samples; and surface water samples. Shallow groundwater is currently not
used at the EMMA OU sites and no future use of the shallow groundwater is expected.
Therefore, a direct exposure  pathway does not exist. Because the shallow groundwater at the
EMMA OU does not represent a complete exposure pathway, groundwater flow and the extent of
affected groundwater at the EMMA OU has not been thoroughly characterized. A detailed
discussion of the RI data is presented in Section 4.0 of the RI Report.

6.1   Site COC-1

Site COC-1 is approximately 100 by 200 fleet in area.  It contains a small circular depression near
the center.  An east-west oriented benn approximately 3 feet high extends along the norm end of
the site.  This site is suspected of formerly being a burial and detonation disposal  area. The benn
appears to be a burial mound for mine springs which are flat metal discs resembling a wagon
wheel.  By themselves the springs have no explosive capability.

Lead was detected in surface soil samples across the site at concentrations ranging from 22.5 to
 197 milligrams per kilogram (mg/kg).  Lead concentrations above background appear to occur
primarily in surface soils.  All but three at-depth soil samples (>4 feet) exhibited lead
concentrations below background or detection levels.  The three soil samples with lead
concentrations detected above background ranged from 21.3 to 33.6 mg/kg.  Background
concentrations of lead are considered to be below 21.1 mg/kg (ESE, 1994).   Lead was also
detected in the offsite sediment sample (21.9 mg/kg).  Noticeable concentrations of iron were
detected in soils along with chromi  i, lead, zinc, cobalt, copper, mercury,  nickel, and silver.

Chloride P1.6 milligrams per liter (mg/L)] and sulfate (1,600 mg/L) were detected above
background concentrations in the groundwater during Phase I of the RI, but were not detected
 above background during Phase II. A probable cause of the variance is the greater influx of
 groundwater during  Phase II sampling as evidenced by the elevated water levels noted.  Metals
 detected in groundwater samples above background or detection limits include cadmium,
 aluminum, iron, manganese, vanadium, arsenic, chromium, lead, selenium, zinc, barium, copper,
 nickel,  potassium, silver, and thallium. No nitroaromatic compounds were detected in any of the
 groundwater, soil, or sediment samples collected.
 craborch-*6/rod-«/04/l9/96                         20               Environmental Science £ Engineering. Inc.

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                                                    Crab Orchard National Wildltfc R&tge EMMA OU KOD
6.2   Site COC-2

Site COC-2 is approximately 250 by 350 feet in area and encompasses an old burn furnace and
two depressions.  A subsurface clay drain tile extends to the northeast from the site and
discharges into a dry stream.

Lead was detected above background levels in Site COC-2 soil samples (ESE, 1994).  Ash was
observed at a depth of 4 inches in the old burn furnace area.  Other metals above background
concentrations detected in the soil samples at this site include antimony, beryllium, calcium,
chromium, copper, iron, and mercury primarily from the 0- to 2-foot interval samples.
Monitoring well soil  boring samples contained TNT at depths of 5 to  7 feet (1.05 mg/kg) and 12
to 14 feet (1.50 mg/kg).  A sediment sample collected from a dry streambed northeast of the
discharge point for the clay drain tile exhibited selenium concentrations above background.

Metals detected above background levels in groundwater samples included barium, iron,
manganese, potassium, and selenium.  Chloride, fluoride, and sulfate were also present above
background levels. One groundwater sample exhibited TNT concentrations above detection
limits.

6.3   Site  COC-3

Site COC-3 is a large area subdivided into two smaller areas. This site exhibits indications of
explosives/munitions activity.  A number of suspect berms or mounds and several detected
magnetic anomalies are located within the site. The southern half of the site is fenced and fairly
heavily wooded.  Various sized pieces of TNT, metal debris, and transite tile (contains asbestos)
are scattered  across the northern half of the site.  This area of concentrated debris remains largely
unvegetated.  The debris is largely concentrated on the west bank of a north-south oriented
erostonal gully that bisects the northern portion of the site. A zone of stained soil is apparent
approximately 2 feet below the top of the gully bank.  This zone of stained soil is the surrkial
expression of the apparent burn layer encountered in test pits excavated on die debris pile. A
sample taken from the stained soil contained 223,000 mg/kg of TNT. Nitroaromatic compounds
detected in the soils  above detection limits in this area include TNT (the most prevalent
compound); l,3,5-trimtrobenzene(l,3,5-TNB); 2-amino-4,6-dinitrotoluene(2-amino-4,6-DNT);
2,4-DNT; 1,3-dinitrobenzene (1,3-DNB); 2-nitrotoluene; 4-nitrotoluene; tetryl; 2,6-DNT; and
4-amino-2,6-DNT.  The most prevalent metal compounds present in soils in mis area include
beryllium, copper, antimony, mercury, and lead.  Other metals present in soil include arsenic,
barium, calcium, cadmium, chromium, cobalt, iron, magnesium, manganese, nickel, selenium,
silver, and zinc.  Nitroaromatic compounds detected in Site COC-3 soil samples were observed
primarily in the 0- to 2-foot interval samples, with two borings exhibiting nhroaromatk
compounds in the 3- to 5-foot interval and one boring exhibiting nitroaromatic compounds in the
 7- to 9-foot interval  samples.  The prevalent metals (described above) detected in Site COC-3 soil

 cr«boreb-«6/roe«ri*i. Inc.

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                                                    Crab Orchard National WUettffe Refuge EMMA OU ROD
samples were observed primarily in the 0- to 2-foot and 7- to 9-foot interval samples, with four
borings exhibiting the metals compounds in die 3- to 5-foot interval and two borings in the 4- to
6-foot interval samples.

.Nitroaromatic and metal compounds above background or detection limits were also detected in
Site COC-3 sediment samples.

Surface water samples collected at Site COC-3 exhibited nhroaromatic and metal compounds
above background concentrations including High Melting Explosive, cyclotetramethylenetetra-
nitramine, octahydro-l,3,5,7-tetranitro-l,3,5,7-tetrazocine (HMX); 2,4-DNT; copper; selenium;
and sulfate.

Nitroaromatic compounds above detection limits present in groundwater samples included Royal
Demolition Explosive, cyclonite hexahydro-l,3,5-trinitro-l,3,5-triazine (RDX); nitrobenzene;
TNT; 1,3,5-TNB; 2,6-DNT;  2-nitrotoluene; 3-nitrotoluene; 4-amino-2,6-DNT; and
2-amino-4,6-DNT.  Both wells exhibited thallium and iron concentrations above background or
detection limits in groundwater samples. Additional compounds detected include chloride,
fluoride, and sulfate.

6.4   SiteCOC-4

Site COC-4 is located across  the road and slightly norm of Site COC-3. It is rectangular in area
and measures approximately 250 by 600 feet.  The area is heavily wooded with a number of
shallow man-made depressions scattered throughout A deeper man-made depression located at
the norm end of the site retains water and has become a pond. These depressions are thought to
be the result of detonation disposal.

 Soil samples exhibited TNT above detection limits. Numerous metals were detected in soil
 samples including beryllium, cadmium, calcium, cobalt, copper, iron, magnesium,
 nickel, silver, and zinc.  Sediment samples collected from the depression exhibited detectable
 levels of antimony, beryllium, cadmium, copper, iron, and TNT.

 Surface water samples collected from the man-made depression exhibited detectable metal
 concentrations including aluminum, barium, calcium, chromium, cobalt, copper, iron,
 magnesium, manganese, nickd, potassium, sodium, vanadium, and zinc. The groundwater
 samples collected from mis site exhibited detectable concentrations of chloride, sulfate, TNT,
 barium, iron, lead, and potassium.
 crmborch-*6/rod-«/O4/19/96                          22              Environmaaal Science A Engineering. Inc.

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                                                   Crab Orchard National Vftdfye Refuge EMMA OV ROD
6.5   Site COC-5

Site COC-5 is a fenced, heavily vegetated area approximately 210 by 280 feet in size. A shallow
man-made depression is located in the southwestern corner of the site. A steeply sloped
depressed area on the eastern side of the site forms a north-south oriented canyon-type feature.

TNT concentrations above detection limits were exhibited in a 5- to 7-foot interval soil sample as
well as in a sediment sample (1.4 rag/kg) from the man-made depression. TNT was not observed
in Phase n sediment samples.

Chloride, fluoride, and sulfar were detected in the groundwater samples collected from this site.
Various metals including barium, cadmium, iron, manganese, potassium, selenium, and vanadium
were also detected in shallow groundwater samples.  Arsenic was detected in a  Phase I surface
water sample.  No organic constituent concentrations were observed above detection limits in
surface water samples.

6.6   SiteCOC-6

Site COC-6 is relatively large, triangular in shape, and covers approximately 6  acres. This area
is fenced. There are several variably sized man-made depressions in the central and northern
areas  of the site.  The shape and location of these depressions indicate that they are a result of
detonation disposal activities.  Small metal fragments were observed scattered around these
depressions.  TNT was detected above background concentration limits in soil at this site.
Notable iron levels (up to 102,000 rag/kg) were also observed.  Beryllium, lead, and mercury
were  detected in soil boring samples at depth. Additional metals detected in soil samples
collected at this site include antimony, barium, cadmium, calcium, cobalt, copper, iron,
magnesium, nickel, potassium, silver, and zinc.   Many of these metals are found in the 19- to
21-foot and 12- to 14-foot intervals.  Two sediment samples exhibited detectable TNT
concentrations.  Metals were noted in other sediment samples including antimony, barium,
cadmium, calcium, and magnesium.

Metal compounds detected above background in the surface water include aluminum, barium,
calcium, iron, magnesium, manganese, potassium, and sodium.  Groundwater samples also
exhibited levels of metals above background including potassium, selenium, zinc, cadmium,
chromium, lead, mercury, iron, barium, and nickel. Elevated levels of chloride (366 mg/L),
fluoride (0.40 mg/L), and sulfate (478 mg/L) were also detected in the groundwater. No
nitroaromatic compounds were noted above detection limits in the surface water or groundwater
samples.
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                                                     Crab Orchard National Wildlfc Kefiige EMMA OU ROD
6.7   SiteCOC-7

Site COC-7 consists of approximately 2 acres of open area within a large field.  An intact land
mine and land mine casing fragments found at mis site provide evidence of detonation disposal
activities in this area.  The intact landmine was not fused, and therefore, did not pose an
immediate detonation hazard. However, it was determined to be filled with the original explosive
filler, indicating a potential for detonation. The mine was isolated, collected, and destroyed by
the exploded ordnance demolition (EOD) team.  The characteristic depressions observed at other
disposal sites are not evident at Site COC-7.  No nitroaromatic compounds above detection limits
were detected in soil samples collected from this site.  Metals detected above background in the
soil include calcium (2,530 mg/kg) and cobalt (22.9 mg/kg).

Groundwater samples collected from mis site exhibited levels above background or detection
limits of cadmium,  iron, potassium, and selenium, as well as detectable  levels of chloride,
fluoride, and sulfate. A low level of TNT (0.00021 mg/L) was detected'in the Phase I
groundwater sample. However, no nitroaromatic compounds were detected in the Phase n
sample.  A probable cause of this variance is the greater influx of groundwater during Phase n
sampling as evidenced by the elevated water levels  noted during Phase O.

6.8   Site  COC-8

Site COC-8 is located in an open  area within a field mat is currently fanned.  Two magnetic
anomalies detected  during die Confirmation Study were investigated during the RI. Magnetic
anomalies investigated at mis site were identified as a sickle blade and metal fence posts.  No
nitroaromatic compounds were detected in samples  collected from mis site. Metals were detected
in soil samples collected from test pits at Site COC-8. Mercury was detected at 0.088 mg/kg,
calcium at ".340 mg/kg, and copper at 20.1 mg/kg. Mercury was detected at a concentration
only slightly  above the average background concentration (0.046 mg/kg).  The source of the
mercury may be a result of use of agricultural chemicals for fungal or pest control. A probable
source of the copper and calcium detected at this site is past farming activities [i.e., the metal
farm implements noted  above or use of agricultural insecticides and/or fungicides  (copper), and
lime or other additives to the soil (calcium)].

6.9   SiteCOC-9

Site COC-9 is an irregularly shaped area approximately 4 acres in size.  This area is  heavily
vegetated with fencing around the northern portion of the site. There are several man-made
depressions located in mis area, with two  located near the southern end  and the others located
near die center and northern portions of the site. The origin of the depressions is thought to be
the result of ordnance disposal activities.  Samples  collected from test pits revealed a subsurface
ash layer roughly IS feet in diameter, providing evidence of burning at  this site.
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                                                    Crab Orchard National Wildlife Refuge EMMA OV ROD
Most of the samples collected from each medium at this site exhibited metals concentrations above
background with the most prevalent being arsenic, antimony, cadmium, chromium, copper, iron,
lead, nickel, and selenium.  Additional metals detected in the soil in mis area included aluminum,
barium, beryllium, calcium, cobalt, magnesium, mercury, potassium, silver, sodium, thallium,
vanadium, and zinc.  The highest metals concentrations were observed in soil samples from the 0-
to 2-foot and 4- to 6-foot intervals. Detectable levels of TNT and 1,3,5-TNB were present in
sediment samples collected from the southern and northern depressions at this site. The most
commonly noted metals in the sediments were antimony, cadmium, copper, lead, and mercury.
Additional metals detected in the sediment include arsenic, beryllium, chromium, iron, nickel,
selenium, silver, thallium, and zinc.

Several metals concentrations above background were detected in surface water samples including
aluminum, barium, calcium, cobalt, copper, iron, magnesium, manganese, nickel, selenium, and
zinc. HMX was detected in a single surface water sample.  Elevated sulfate levels were also
detected in surface water samples. Although TNT was detected in the Phase I groundwater
sample, no nitroaromatic compounds were detected in the Phase II groundwater samples. A
probable cause of this variance is the greater influx of groundwater during Phase n sampling as
evidenced by the elevated water levels noted during Phase II.   Metals concentrations noted above
background in groundwater samples include arsenic, cadmium, cobalt, iron, manganese, nickel,
potassium, selenium, silver, thallium, vanadium, and zinc.  Chloride, fluoride, and sulfate were
also detected in the Phase I groundwater sample.

A sediment sample collected downgradient to the north of the site exhibited no nitroaromatic
compounds or metals concentrations above background.

6.10 SiteCOC-10

Site COC-IO is small,  approximately 120 feet square and consists of a fenced area on the northern
edge of a corn field. This COC site is closer to the COP area than to the other COC sites.  A
large portion of the site is taken up by an irregularly-shaped man-made depression. No ordnance
components were observed at this site.

One soil sample collected in Phase I exhibited levels of nitroaromatic compounds above detection
limits (nitrobenzene at 0.0058 rag/kg). Two Phase I sediment samples contained TNT at 0.66 and
0.72 mg/kg. Phase II soil and sediment samples exhibited no detectable nitroaromatic
compounds. The RI determined that explosive effects on soil and sediment at this site were
defined and localized.  Beryllium, barium, cadmium, and copper were also detected in sediment
samples above background. Sediment samples collected downgradient of the site showed no
levels of site constituents above background or detection limits, indicating that surface migration
 from this site has not occurred.
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                                                   Crab Onhard National Wildlife Kefiige EMMA OU ROD
Aluminum, barium, calcium, copper, iron, magnesium, manganese, potassium, sodium,
vanadium, and zinc were present in above background levels in surface water samples.
Groundwater samples from this site exhibited no detectable nitroaromatic compounds.  Arsenic,
barium, beryllium, chromium, potassium, thallium, chloride and sulfate were detected in
groundwater above background concentrations.

6.11  SiteCOP-1

Site COP-1 is an area containing a man-made impoundment that received drainage from the
Group n process buildings.  Drainage from the impoundment is through a 12-inch pipe on the
west side of the impoundment to a small stream.  This stream d.~ains north to Crab Orchard Lake.
Numerous metals were detected in sediment samples collected from the  impoundment and from
the streambed.  However, few of the metals are consistently present in the samples.  The metals
most commonly detected above background in sediment samples were calcium, lead, and
mercury.  Additional metals detected in the sediment include antimony,  beryllium, chromium,
cobalt, copper, manganese, silver, and zinc.  One impoundment sediment sample and two
streambed sediment samples exhibited detectable levels of TNT. The compound 2,6-DNT was
detected in one streambed sediment sample.

Surface water samples from the impoundment exhibited detectable levels of RDX, HMX, and
1,3-DNB. Metals present in above background levels in the impoundment surface water samples
include aluminum, barium, cadmium, calcium, copper, iron, magnesium, manganese, sodium,
vanadium, and zinc. The groundwater sample collected in Phase I exhibited detectable levels of
1,3,5-TNB, antimony, beryllium, cadmium, and potassium.  Also, chloride, fluoride, nitrate, and
sulfate were detected.  With the exception of thallium at 0.0031 mg/L, no metals were detected in
the Phase n groundwater sample at concentrations above background levels.  No nitroaromatic
compounds were detected in the Phase n groundwater samples.  A probable cause of the variance
in analytical results between the Phase I and Phase n sample events is the greater flux of
groundwater during Phase II sampling as evidenced by die elevated water levels noted.

6.12 SiteCOP-2

Site COP-2 is a former underwater storage area for bulk explosives.  Sodium is die most
commonly detected constituent above background concentrations at this site, being present  in most
of the surface soil samples (0- to 2-foot interval) at concentrations ranging from 1,860 to
3,970 mg/kg and one soil boring sample (5- to 7-foot interval) at 1,960 mg/kg collected during
the installation of a monitoring well.  Magnesium, calcium, and mercury were present above
background in one soil sample collected during installation of monitoring well MWS-1. Lead
(24.9 mg/kg) and cobalt (22.1 mg/kg) were each detected in one surface soil sample.  No
nitroaromatic compounds or organic constituents were detected in soil samples collected.
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                                                    Crab Orchard National WiUBfc Kefitge EMMA OU ROD
Groundwater samples exhibited detectable levels of metals including arsenic, selenium, and
thallium. Additional metals detected in groundwater samples include barium, iron, and
potassium.  Chloride, fluoride, nitrate, and sulfate were also detected  in groundwater samples.
TNT was detected in one groundwater sample during the  Phase I sampling at a concentration of
0.0002 mg/L.  No nitroaromatic compounds were detected in the Phase n sampling.

6.13  SiteCOP-3

Like Site COP-2, Site COP-3 is a former underwater storage area for bulk explosives. Metals
detected above background in soils include arsenic, barium, beryllium, calcium, cobalt, iron,
magnesium, manganese, mercury, and silver.   Iron, calcium, magnesium, and manganese were
the most prevalent metals detected. The remaining metals were detected in only one or two soil
borings at various intervals between 0 and 21 feet.  One soil boring exhibited TNT at the 4- to
6-foot interval at 0.25 mg/kg.  Sediment samples collected from areas draining this site contained
no nitroaromatic compounds or above background metals.

Elevated levels of aluminum (21 mg/L) and iron (10.1 mg/L) were detected in Phase I
groundwater samples.  Additional metals above background in  the Phase I groundwater samples
include antimony, barium, beryllium, cadmium, chromium, cobalt, manganese, and vanadium.
Phase n groundwater samples exhibited an elevated chromium  level (0.417 mg/L) in one well and
1,3-DNB (0.332 mg/L) in another. Groundwater samples also exhibited detectable levels of
chloride, fluoride, and sulfate.

6.14 Site COP-4

Three types of disposal activities were identified at Site COP-4.  These activities included burning
operations in the northwest portion of the site, burial activities in the southwest portion, and
surface dumping in the south central portion. The area is bounded by old roads and is transected
in an east-west direction by an old railroad grade. Extensive magnetic anomalies (identified in the
area south of the railroad tracks) and debris (found during excavation of test pits in this area)
indicate that this area may have been used as a burial or disposal area.  The area north of the
railroad tracks is reported to have been used to burn ordnance. Land mine casings and pieces of
TNT have been  observed on the surface in the southeast corner of Site COP-4 in an area referred
to as the former land mine disposal area.

TNT, HMX, RDX, and  1,3,5-TNB were detected in samples collected  from the surface and
throughout the soil  column to a depth of 6 feet in die burial area south of the railroad tracks.

Concentrations of 2-amino-4,6-DNT,  2,6-DNT, 2-nitrotoluene, and 4-nitrotoluene were also
detected in soil samples.   HMX and RDX were also detected in one soil boring in the 12- to
 14-foot interval:  Metals  such as antimony, arsenic, barium, beryllium, cadmium, calcium,

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                                                    Crab Orchard National Wildlife Refuge EMMA OV ROD
chromium, cobalt, copper, iron, lead, magnesium, manganese, mercury, nickel, silver, sodium,
thallium, and zinc were also detected in soils in varying sample intervals.

Surface soil samples collected from the reported burn area north of the railroad grade contained
no detectable concentrations of nitroaromatic compounds.  One surface soil sample exhibited
levels of barium, calcium, copper, lead, silver, and zinc above background concentrations.  Soil
samples collected from the former land mine disposal area revealed significant concentrations of
nitroaromatic compounds. Constituent concentrations are highest in the surface soils for RDX
and TNT in various sampling intervals between 0 and 10 feet.  Metals detected in soil samples
were sporadic in this area.  Only three metals were detected above background more man once:
calcium, lead and mercury.

Metals detected above background in groundwater samples include aluminum, antimony, arsenic,
barium, beryllium, cadmium, chromium, cobalt, copper, iron, lead, manganese, selenium, silver,
vanadium, and zinc.  Arsenic, beryllium, chromium, copper, lead, and zinc were detected at
levels above background  in samples from Weil COP4-3 during the Phase n sampling. RDX was
detected  in Phase n groundwater samples at 0.00118 and 0.00199 mg/L.  No Phase I
groundwater samples exhibited detectable concentrations of nitroaromatic compounds.

6.15  Site  Bunker 1-3

The Bunker 1-3 Site is one of approximately 85 bunkers in Area 13 originally built for storage of
500-pound bombs.  Many of the bunkers are still being used by Olin Corporation and
U.S. Powder to store explosive materials.  There was a report of a chemical spill occurrence at
Bunker 1-3.  This spill apparently occurred in the adjacent field to the northwest side of the
bunker and was evidenced by an area of discolored vegetation.  The nature of the spilled chemical
is unknown.  This area was investigated in the 1988  RI and referred to as Site 19 (O'Brien &
Gere,  1988).

During the Phase I investigation, one monitoring well was installed and sampled, and three
composite surface soil samples were collected to investigate the potential residues of the reported
spill.  The vegetation in this area appeared normal.  No sign of the reported discolored vegetation
or other evidence of impact was observed during the Phase I field activities. One confirmatory
groundwater sample was collected from Well MW-BKR1-3-1 during the Phase II investigation and
analyzed for  nitroaromatic compounds and priority pollutant metals. None of the surface soil,
monitoring well boring soil, or groundwater samples exhibited any nitroaromatic compounds
above detection limits or metals above background levels.
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                                                    Crab Orduud National m&frR&gc EMMA OU ROD
6.16  Summary

Based on the findings of the RI Report, environmental media (soil, sediment, surface water, and
groundwater) at 13 of the 15 sites in the EMMA OU have been affected by lOP-related activities.
The sites contain metals (such as lead) and nitroaromatic compounds in various media above
background concentrations.  Results of the chemical analyses indicate that Sites COC-3, COC-9,
and COP-4 exhibit the greatest effects from lOP-related activities. These sites were subject to
disposal activities and exhibit nitroaromatic compounds and metals (such as lead) concentrations in
soil, sediment,  surface water, and groundwater.  Data indicate that lOP-related constituents are
present at the EMMA OU in discrete, localized areas within defined boundaries.
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                                                   Cntb Orchard National Wildltfe Refuge EMMA OV ROD
                            7.0  Summary of Site Risks

In order to characterize the potential current and future threats to human health and the
environment that may be posed by the constituents at the EMMA OU, a BRA Report was
prepared in accordance with USEPA's Risk Assessment Guidance for Superfund (RAGS):
Volumes 1 - Human Health Evaluation Manual (Part A) and Volume II - Environmental
Evaluation Manual.  Because the EMMA OU sites are located on a national wildlife refuge,
additional ecological studies were conducted to ensure a thorough characterization of the potential
ecological risks posed by the EMMA OU sites.  A Preliminary Ecological Risk Assessment
(Preliminary Assessment) was completed in September 1993.  The purpose of the Preliminary
Assessment was to determine if any of the EMMA OU sites would require further characterization
during Phase n of the RI field investigations. The result of the Preliminary Assessment indicated
that further characterization was required at Sites COC-1,  COC-3, COC-5, COC-6,  COC-9,
COC-10, COP-1, and COP-4. The additional data required at these sites were predominately
surface water and sediment data in order to determine risks to aquatic life.  Soil samples were
required at some of the sites, and small mammal trapping  was conducted in order to characterize
the risks posed by constituents of concern found in the soils at Site COC-9.  In addition, aquatic
toxicity testing was conducted on water samples obtained from Site COC-6. The purpose of the
aquatic toxicity testing was to determine if surface water from Site COC-6 would adversely effect
the survival, growth or reproduction of an aquatic test species. The additional data  collection
activities were conducted during the Phase U RI field investigations and the results were
incorporated into the BRA Report (Volume HI of the RI Report).

7.1   Human Health Risks

7.1.1    Identification of Constituents of Concern

Over 40 constituents (including volatile organics, nitroaromatic compounds, and inorganics) were
detected in the soil, groundwater, surface water, sediment and/or animal tissue samples
(Site COC-9)  collected at the EMMA OU sites. After a screening of constituents was conducted,
during which blanks, background concentrations, and data useability were considered, a total of
45 constituents were selected as potential constituents of concern for the EMMA OU sites.  These
45 constituents were used to evaluate the risks posed at the EMMA OU sites.  However,  not
every constituent selected was detected at every EMMA OU site nor in every  environmental
medium sampled. As a result, for  each exposure pathway evaluated in the BRA, the potential
human health risks were characterized based on the detected potential constituents of concern
present in the relevant medium at each EMMA OU site.  The results of the BRA showed that
potential unacceptable human health risks were limited to  RDX;  1,3,5-TNB; and TNT in the soil.
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                                                        Orchard National Wildlife Refuge EMMA OV ROD
7.1.2   Human Health Exposure Assessment '

The exposure assessment in the BRA identified potential receptors and complete exposure
pathways, and estimated chemical intakes for potentially exposed populations. The following
human receptor groups were evaluated for quantitative evaluation in the BRA:
       •   on-site workers; and
       •   recreational users.

Exposures to potential human receptors were evaluated in the BRA for soil, air, surface water,
and sediment.  Exposure pathways evaluated were incidental ingestion, dermal contact, and
inhalation.  The shallow groundwater direct exposure pathway was not evaluated in the BRA
because mere is currently no use of the shallow groundwater, and no future use of the shallow
groundwater is  expected at the EMMA OU sites (i.e., it is an incomplete exposure pathway).
The food chain  (bioaccumulation) pathway was evaluated for human recreational receptors.

Future human and ecological exposure scenarios are expected to remain unchanged from the
current scenarios at the EMMA OU. Because the site is a National Wildlife Refuge, future
residential development is not possible. However, hi the event mat the refuge property would be
transferred to the private sector,  such a transfer would be subject to CERCLA/SARA
Section 120(h)(3) and (4). This section states diat the parcels must be uncontaminated or a
covenant must be issued by USEPA that all  necessary remedial action had been taken.  In such a
case, the future use scenario used in the BRA would be reevaluated.

The exposure concentrations for current human exposure to soil were calculated by using only soil
data for the 0- to 2-foot interval at each site. The available surface water and sediment data were
used to calculate the exposure concentrations for these media. The exposure concentrations  for
dust and volat>.~s in  die air were based on the appropriate soil data and estimated concentrations
in air.

For each human exposure pathway evaluated, carcinogenic and non-carcinogenic health risks were
characterized for the reasonable maximum exposure (RME), and the reasonable average  exposure
(RAE) scenarios.  The standard and default exposure assumptions recommended by USEPA's
RAGS were used, as well as conservative assumptions and professional judgement. The methods
and assumptions used in the exposure assessment are presented in Section 3.6 of the BRA Report.

7.13  Human Health Toxicity Assessment

Available toxicity factors of carcinogenic and noncarcinogenic chemicals of potential concern are
discussed and presented in Section 4.0 of the BRA  Report (Volume HI of me RI Report). The
chemicals of potential concern selected for the risk assessment for die site have a wide range of
carcinogenic and noncarcinogenic effects associated with them.  The reference dose (RfD) values

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                                                    Crab Orchard National Wtldlife Refuge EMMA OV ROD
and carcinogenic slope factors (CSF) were key dose-response variables used in the BRA.' The
RfD, expressed in units of milligrams per kilogram per day (mg/kg/day), for a specific chemical
is an estimated daily intake rate that appears to pose no risk over a lifetime of exposure.  The
RfD value is used to assess noncarcinogenic effects. The CSF, expressed in units of
(mg/kg/day)'1 provides a conservative estimate of the probability of cancer development from a
lifetime of exposure to a particular level of a potential carcinogen. Brief toxicity summaries of
the chemicals of potential concern that may present the greatest carcinogenic risks and are present
at the highest concentrations at the site are presented in Appendix F of the RI Report.

7.1.4   Human Health Risk Characterization

Potential excess carcinogenic risks were calculated for individual constituents by multiplying
exposure levels of each constituent by the appropriate CSF. The total combined potential health
risks were also evaluated for each pathway by summing estimates derived for each constituent of
concern for mat pathway.  Risks from inhalation,  skin absorption, and oral exposures can be
added to estimate total overall potential risk to human receptors.

The site-specific potential carcinogenic risk estimates were based on the RME and RAE scenarios.
The potential cancer risks associated with the known or suspected carcinogens detected at the
EMMA OU sites were compared to the USEPA acceptable cancer risk range of l.OE-4 to
l.OE-06.

The potential for noncarcinogenic effects was evaluated by comparing an exposure level over a
specified time period (e.g., the daily dose in mg/kg/day for a long period up to a lifetime) with a
RfD derived for a similar period (USEPA, 1989a).  This ratio of exposure to toxicity is called a
noncarcinogenic hazard quotient (HQ).  The HQ assumes mat there is a level of exposure below
which it is unlikely for even sensitive populations to experience adverse health effects (USEPA,
1989).  If the exposure level exceeds the threshold level fl.e., if the HQ exceeds one or unity),
there may be concern for potential  noncarcinogenic effects. Total pathway hazard indexes (His)
were calculated by summing the HQ for each constituent of concfn.  This additive approach
assumes that multiple subthresbold  exposures could result in an adverse effect and mat the
magnitude of die effect is proportional to the sum of the ratios of the exposure to acceptable
exposures. The possible effects of multimedia exposures were evaluated by summing the HI
values for die relevant exposure routes.

The BRA determined mat there are no potential unacceptable human health risks associated with
potential exposures to constituents at Sites  COC-1, COC-2, COC-4, COC-5, COC-6, COC-7,
COC-8. COC-9, COC-10, COP-1, COP-2, COP-3, and Bunker 1-3 (ESE, 1994). Although
Site COC-9 has an HI of 3.0E+00 for die RME scenario, when mis HI is evaluated on die basis
of critical effects, die total His for each effect are less than unity. Therefore, there  are no
potential unacceptable risks to human health at Site COC-9.

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                                                   Crab Orchanl National Wildlife Refitge EMMA OU ROD
Potential unacceptable human health risks are associated with potential exposures to constituents
of concern in surface soils at Site COC-3.  Potential unacceptable human health risks are
associated with concentrations of 1,3,5-TNB and TNT in soil.  The potential unacceptable human
health risks posed by Site COC-3 are as follows:  the total adult worker His (all pathways) range
from 1E+01 to 5E+02. The total adult worker potential carcinogenic risk levels (all pathways)
range from 8E-05 to 3E-03. The total adult and child recreational user His range from 2E+01 to
2E+02 and from 6E+01 to 5E+02, respectively. The total recreational user potential
carcinogenic risk levels (all pathways) range from 5E-05 to 1E-03 (ESE, 1994).

As indicated by the BRA, potential unacceptable human health risks are associated with potential
exposures to constituents of concern in surface soils at Site COP-4 (ESE, 1994). Potential Laman
health risks at Site COP-4 are associated with concentrations of RDX, 1,3,5-TNB, and TNT in
soil.  The total adult worker His (all pathways) range from 9E+00 to 3E+02, and the total adult
worker potential carcinogenic risk levels (all pathways) range from 1E-04 to 8E-03.  The total
adult and child recreational user His range from 1E+01 to IE+02 and from 3E+01 to 4E+02,
respectively. The total recreational user potential carcinogenic risk levels for all pathways
combined range from 1E-04 to 3E-03.
7.2   Ecological Risk Summary

7.2.1   Identification of Constituents of Concern

Over 40 constituents (including volatile organics, explosives, and inorganics) were detected in
soil, groundwater, surface water, sediment, and/or animal tissue samples (Site COC-9) collected
at the EMMA OU sites.  After a screening of constituents was conducted, during which blanks,
background concentrations, and data useabilhy were considered, a total of 45 constituents were
selected as potential constituents of concern for the EMMA OU sites.  These 45 constituents were
used to evaluate the risks posed at the EMMA OU sites. However, not every constituent selected
was detected at every EMMA OU site nor in every environmental medium sampled.  As a result,
for each exposure pathway evaluated in the BRA, the potential ecological risks were characterized
based on me detected potential constituents of concern present in the relevant medium at each
EMMA OU site.

Potential ecological risks were characterized based on the detected constituents of concern present
 in the relevant medium at each EMMA OU site. Information about the specific constituents of
concern detected at each  site and in each medium is presented in Section 6.0 of this ROD.

 Based on the results of the BRA, the constituents of concern that pose an unacceptable ecological
 risk were identified.  These constituents occurred at Sites COC-3, COP-4, COC-4, and COC-6.
 For Site COC-3, these constituents of concern are 1,3,5-TNB; TNT; iron; lead; and zinc  in the

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                                                     Crab Orchard National Wildlife Kffuge EMMA OU ROD
soil. For Site COP-4, the constituents of concern are HMX; RDX; 1,3,5-TNB; 2,4,6-TNT; and
zinc in the soil.  At Site COC-4, the constituents of concern are 2,4,6-TNT, aluminum, and iron.
At Site COC-6, the constituent of concern is manganese.

7.2.2   Ecological Exposure Assessment

The exposure assessment in the BRA identified potential receptors and complete exposure
pathways, and estimated chemical intakes for potentially exposed  populations.  Terrestrial,
aquatic, and vegetative ecological receptor groups were evaluated for quantitative evaluation in the
BRA (Volume III of the RI Report).

Exposures to potential ecological receptors, including a number of terrestrial, aquatic, and
vegetative receptors, were evaluated for soil, surface water, and sediment.  Because direct
exposure of ecological  receptors to groundwater is not expected at the EMMA OU sites, this
exposure pathway was  not evaluated in me BRA. The groundwater pathway was evaluated in the
ecological risk assessment in terms of potential groundwater discharge to surface water causing
potential risks to aquatic species through exposure to affected surface  water and sediment  The
food chain (bioaccumulation) pathway was also evaluated for ecological receptors. Future
ecological exposure scenarios are expected to remain unchanged from the current scenarios at the
EMMA OU.

Current ecological exposure scenarios at the EMMA OU sites included a number of terrestrial and
aquatic receptors.  Because of the large number of different species of wildlife that are known or
suspected of inhabiting the EMMA  OU sites, it was not possible to evaluate all ecological
receptors.  The ecological receptors were screened based on the analysis of the ecological setting
and site characteristics, and a determination of those communities/species critical to the ecological
risk assessment.  A detailed analysis of the ecological receptors is presented in Section 3.4.2 of
die BRA (Volume III of the RI Report). After the analysis of the ecological receptors was
conducted, indicator species were selected.  These indicator species were chosen from the list of
potential ecological receptors and are those species that appeared to be at greatest risk from
exposure to potential constituents of concern.

The selected representative ecological receptors are the following:
        •    Large mammal (white-tailed deer — recreational importance);
        •    Small  mammal (mouse and squirrel — high abundance in food chain);
        •    Bobwhite quail (potential for bioaccumulation — primary consumer);
        •    Red-tailed hawk/American kestrel (bioaccumulation — secondary consumer);
        •    Bald eagle (endangered species at the time of BRA);
        •    Terrestrial vegetation (habitat indicator); and
        •    Aquatic life in general  (water quality indicator).
 cmbotcb-c6/rod-«/04/19/96                          34                Environmental Science A Engineering. Inc.
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                                                    Crab Orchard National Wildlife Refuge EMMA OU ROD
Because the species of concern would be expected to be exposed to surface conditions only, the
upper 0 to 2 feet of soil best represent typical exposure conditions for ecological receptors.
Constituents within the upper 0 to 2 feet of soil are available for uptake by plants, transfer to
food, and ultimate consumption by wildlife. In addition, the available surface water and sediment
data were used to calculate the exposure concentrations for these media.

Potential exposures to mammalian receptors were evaluated for soil, surface water, sediment, and
food. Potential exposures to bobwhite quail were evaluated for the consumption of food only.
Since most of their daily water requirements are met through consumption of food, water
ingestion was not evaluated for the bobwhite quail.  The red-tailed hawk and American kestrel
were assumed to be primarily exposed to constituents of concern through the consumption of prey
such as small mammals.  The bald eagle was ass^mad to be exposed to constituents of concern
through the consumption of fish, in which constituents of concern may bioaccumulate. Aquatic
life was assumed to be primarily exposed to constituents of concern through direct contact with
surface water. The estimation of potential exposure for these aquatic species assume that they are
continuously in direct contact with surface water.

Estimates of potential exposure to constituents through food for terrestrial animals were
determined by approximating the uptake of constituents from soil into plants and multiplying mis
by the amount of vegetation consumed by the animal.  The specific ecological exposure
assumptions are discussed in detail  in Section 3.6.2 of the BRA (Volume III of the RI Report).

7.2.3    Ecological Toxirity Assessment

The toxicities of the constituents of concern were assessed for effects on vegetation, aquatic life,
and terrestrial wildlife, including birds.  Toxicity data for effects on flora were primarily
qualitative, whereas information on fav»a were more quantitative.  Toxicological literature was
reviewed, and touchy values were identified for indicator or related species.  These toxicity
values were converted into units of acceptable daily intake (mg/kg BW/day) and are referred to as
critical toxicity values (CTV). Available CTV for constituents of concern are discussed and
presented in Section 4.3 of the BRA (Volume III of the RI  Report).

Toxicity data for terrestrial wildlife are not nearly as complete as that found for aquatic species.
Consequently, extrapolation of toxicity  data from one animal species to another was often
necessary.  Because of the uncertainty associated with these extrapolations, safety factors were
applied to eco-toxicological endpoints to derive CTVs.  Chronic or sub-chronic toxicity values
 were used when ever possible. A no-observed-effect level  (NOEL) was used over a lowest-
observed-effect level (LOEL).  If only a LOEL was available, a safety factor was applied to
derive a NOEL. The  NOEL safety factor  calculations are presented in Section 4.3 of the BRA
 (Volume m of the RI  Report).
 craborcfa-*6/rod-«A>4/19/96                          35               Environmental Science 4 Engineering. Inc.
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                                                      Crab Orchard National Wildlife Refuge EMMA OU ROD
Toxicity data were limited for those indicator wildlife species for which potential quantitative
exposure was possible for the constituents of concern.  Thus, toxicity values from the literature
were derived using the most closely related species, where possible. The CTVs for white-tailed
deer, squirrel/mouse, bob-white quail, red-tailed hawk/American kestrel, and bald eagle were
found in the literature and used in the BRA.

The toxicity of constituents of concern to aquatic life were assessed by comparing surface water
concentrations at the site to available  acute and/or chronic Ambient Water Quality Criteria
(AWQQ for the protection of aquatic life. These criteria are derived to protect 95 percent of
aquatic organisms, including fish, invertebrates, and aquatic plants.  Therefore, not only fish, but
aiso aquatic invertebrates and plants are protected (USEPA, 1986).  Consequently, comparison of
maximum surface water concentrations with these criteria were used to determine die likelihood of
adverse effects to aquatic life.

Two site-specific studies were conducted at die EMMA OU to study toxicity (Appendices I and J
of the RI Report).  Toxicity of metals constituents to small mammals was studied through tissue
sampling and analysis of several mice live trapped at Site COC-9 and a control area.
Observations and data were statistically evaluated between Site COC-9 and the control area, and
showed no significant differences.  This toxicity study documented a No Observable Adverse
Effect Level (NOAEL) for the concentrations of metals detected at Site COC-9. The toxicity of
surface water at Site COC-6 to aquatic  species was  studied using Ceriodaphnla dubia as a
representative species following procedures approved  by USEPA, IEPA, and USFWS. The
results of the toxicity testing showed  that no  adverse survival or reproductive effects were caused
by  exposure to surface water at Site COC-6.

7.2.4    Ecological Risk Characterization

Potential risks to terrestrial  and aquatic receptors were quantified by comparing the estimated
daily intakes or media exposure concentrations with CTVs.  This comparison  is defined as an
Ecological Risk Index (ERI). Cumulative ERIs were developed to determine whether species of
concern would receive excessive exposure to a mixture of constituents from each route of
exposure.  If the cumulative ERI is greater than 1,  it suggests that the total exposure to all
constituents of concern through all exposure pathways is sufficient to produce a potential risk of
adverse effects to die species of concern.

Potential ecological risks were estimated on die basis  of several  conservative assumptions that
tend to overestimate the actual risks.  Uncertainties in the ecological risk assessment were
associated with elevated detection limits,  fate and transport modeling (sediment equilibrium model
and food uptake models), exposure assumptions (media intake rates), and toxicity information.
The major uncertainty associated with the ecological risk characterization is die lack of available
environmental toxicity data.  In order to quantify the uncertainty associated with exposure and

crmborch-»6/rod-«/O4/19/96                          36                Environmental Science & Engineering, Inf.
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                                                   Crab Orchard Natoiial Wildlife Kefitg* EMMA OV ROD
toxicity assumptions incorporated into the ecological risk assessment, a chronic aquatic toxicity
test was conducted on a surface water sample collected from Site COC-6, and a small  mammal
field study was conducted at Site COC-9.  Details of these ecological studies are presented in the
BRA (Volume HI of the RI Report).  Aquatic toxicity testing suggested mat the estimated
ecological risks to aquatic receptors may be overly conservative by as much as two orders of
magnitude.  In addition, the small mammal field study suggested that estimated ecological risks to
the small mammal may be overly conservative by up to three orders of magnitude.

The BRA determined mat there are no potential unacceptable ecological risks associated with
potential exposures to constituents at Sites COC-1, COC-2, COC-5, COC-7, COC-8, COC-9,
COC-10, COP-I, COP-2, COP-3, and Bunker 1-3 (ESE, 1994).

Potential unacceptable ecological risks are associated with potential exposures to constituents of
concern at Site OOC-3.  Potential unacceptable ecological risks (bobwhite quail and white-tailed
deer) are associated with concentrations of 1,3,5-TNB and TNT in soil. The total white-tailed
deer ERIs range from 1E+04 to 5E+04.  In addition, potential ecological risks  are also
associated with concentrations of iron and lead in soil (the small mammal) and with zinc in soil
(the bobwhite quail). The total small mammal ERIs (all pathways) range from 3E+02 to 1E+04.
The total ERIs for die bobwhite quail range from 5E+06 to 2E+07.

The BRA indicated  that Site COC-4 poses a potential  ecological risk to bobwhite quail, while not
posing any unacceptable risk to human health.  Potential ecological risks associated with
Site COC-4 are several orders of magnitude lower than the potential risks posed by Sites COC-3
and COP-4.  Specifically, potential unacceptable risks exist to  individual small mammals  (ERI
exceeds unity, 4E+00 to 6E+01) and to the bobwhite quail (ERI exceeds unity, 3E+01  to
 1E+02). In order to avoid the application of order-of-magnitude uncertainty factors that result in
risks being overestimated, Site COC-4 will be forth   evaluated.

The BRA also indicated that there is potential unacceptable risk associated wim potential  exposure
to manganese in surface water for the bald eagle at Site COC-6 (ESE, 1994).  However, this
potential unacceptable risk is based on an exposure scenario that is extremely unlikely.

 As indicated by the BRA, potential unacceptable ecological risks are associated with potential
 exposures to constituents of concern at Site COP-4 (ESE.  1994).  Potential ecological risks are
 associated wim concentrations of HMX,  RDX,  1,3,5-TNB,  and TNT in soil for the white-tailed
 deer (ERIs  range from 7E+03 to 4E+04), small mammal (ERIs range from 4E+06 to 2E+07),
 and bobwhite quail (ERIs range from 3E+06 to IE+07).  In addition, potential ecological risks
 are also associated  wim concentrations of zinc in soil for the bobwhite quail.
 cnborch-rt/rod-*/04/19/96                         37               Environmental Seienct A Engineering. Inc.
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                                                    Crab Orchard National Wildlife Refuge EMMA OV ROD
While the ecological risk analysis suggested potential risks to individual animals, it is unlikely that
the local (i.e., refuge) ecosystems would be adversely affected due to the relatively small size of
Sites COC-3 and COP-4. These sites comprise a very small portion of the refuge. The refuge
covers 43,500 acres, while Site COC-3 only covers approximately 71,500 square feet and
Site COP-4 covers approximately 4,900 square feet for a total of 1.75 acres. As a consequence,
this analysis in Section 5.5 of the BRA (Volume ID of the RI Report) strongly suggested that
effects at the population and higher levels of biological organization are unlikely.

7.3   BRA Conclusions

In conclusion, the BRA found that Sites COC-3 and COP-4 pose potential unacceptable human
health and ecological risks. The potential ecological risks are to the white-tailed deer, small
mammal, and bobwhite quail.  Potential ecological risks posed at Sites COC-3 and COP-4 are of
comparable magnitude, with the exception of the potential ecological risk to small  mammals.  The
potential ecological risks to small mammals at Site COP-4 (primarily associated with
concentrations of HMX and RDX) are several orders of magnitude greater than the potential small
mammal risk found at Site COC-3.  Actual or threatened releases of hazardous substances from
Sites COC-3 and COP-4, if not addressed by implementing the response action selected in this
ROD, may present a current or potential risk to public health, welfare, and the environment. As
previously mentioned, Site COC-4 will be further evaluated. Therefore, it has not been
determined if remedial action will be necessary at Site COC-4.
 enbofcb-t6/rod-i/04/l9/96                      .    38               Environmental Science A Engintervig. Inc.
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                                                     Crab Orchard National Wildlife Rtfiigt EMMA OV ROD
                          8.0  Description of Alternatives

Seven alternatives were analyzed in the FS for their ability to protect human health and the
environment, comply with legal requirements, and be cost effective.  The evaluations of capital
costs, operation and maintenance (O&M) costs, net present worth costs, and implementation tunes
presented below are estimates.  Each alternative,  except die No Action  alternative, will include a
provision for land use controls at Sites COC-3 and COP-4. Implementation of land use controls
at Sites COC-3 and COP-4 will reduce the potential for future exposure to the remaining affected
soil (soil containing contaminants above remediation goals) and restrict  die construction of
drinking water wells at Sites COC-3 and COP-4.  These land use controls include restriction of
the following activities: groundwater well installation; subgrade activities; and pond creation
within the perimeters of the soil covers at Sites COC-3 and COP-4.

Under Alternatives 2 through 5 and 7, soil at Sites COC-3 and COP-4 with concentrations of
nitroaromatic compounds greater man 100,000 mg/kg and lead above 450 mg/kg [approximately
270 cubic yards (cy)] will be excavated and transported offsite to a commercial incinerator.  The
soils may be reactive and pose a potential safety hazard ("Explosives Safety," U.S. Army
Technical Center for Explosives Safety, June 1995). The soil will be rendered safe prior to
shipment for offisite treatment and disposal.  The excavated soil with greater than  100,000 mg/kg
nitroaromatic compounds and 450 mg/kg lead will be classified by appropriate waste code(s) prior
to shipment for offsite treatment and disposal.  Potential waste codes that may be  associated with
the excavated  soil  include D003 (reactive), D008 [toxicity characteristic leaching procedure
(TCLP) lead at 5 mg/L] and D030 (TCLP 2,4-DNT at 0.13 mg/L).

Soils remaining after the above removal action will be tested using TCLP.  Any soil that is shown
by TCLP testing to fall within the RCRA definition of a "characteristically hazardous waste" will
be excavated and properly treated and disposed of at a RCRA tr  -anent, storage,  and disposal
(TSD) facility.

Under Alternatives 2 through 7, groundwater monitoring will  occur at Sites COC-3 and COP-4.
The scope of the groundwater monitoring program presented  in Table 5-2 of this ROD is for
costing purposes only. The final groundwater monitoring program will be developed during
design as part of the O&M plan.  The construction of fencing for Alternative 2 will consist of an
8-foot high chain link fence,  2  feet of which will be buried.

Under Alternatives 3A, 3B, 3C, SB, and 5C, where the installation of covers/caps are specified,
O&M activities will include periodic maintenance and repair of the coven/caps. Repairs to the
soil covers/caps will be made as required. O&M activities will also include long-term
maintenance of the fencing under Alternative 2.
 cr*bocch-«6/rod-«/05/07/96                          39               Environmental Science A Enguuer+1. Inc.
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                                                 Crab Orchard National WilMfr Kefitge EMHA OV HOD
8.1   Alternative 1 — No Action

The No Action alternative leaves the EMMA OU sites in their current condition. Monitoring will
not take place under this alternative.  No remedial actions that result in the treatment,
containment, or removal of affected soil are implemented under Alternative 1.  The NCP requires
the consideration of a No Action alternative. The No Action alternative is also used as a baseline
for comparison with other remedial alternatives.
      Capital Costs                        $0
      Present Worth O&M                  $0
      Total Present Worth Costs              $0
      Tune to Construct                 .    0

8.2   Alternative 2 — Removal/Fencing/Land Use Controls/
       Groundwater Monitoring

Alternative 2 consists of the following elements:
    •  removal and offsite treatment (offsite incineration) and disposal of soil containing
       nitroaromatic compounds greater than 100,000 rag/kg and lead above 450 mg/kg
       (approximately 270 cy);
    •  sampling to ensure that remaining affected soil (i.e., soil with contaminants above
       remediation goals) at Sites COC-3 and COP-4 does not exhibit the characteristics of a
       RCRA hazardous waste for lead and 2,4-DNT;
    •  backfill excavated area to grade;
    •  construction of fencing around the remaining affected soil at Sites COC-3 and COP-4;
    •  long-term maintenance of the fencing;
    •  groundwacer monitoring at Sites COC-3 and COP-4; and
    •  implementation of land use controls.

       Capital Costs                 $3,011,000
       Present Worth O&M Costs      $292,400
       Total Present Worth           $3,303,400
       Time to Construct              4  months

 8.3   Alternative 3 — Removal/Land Use Controls/Groundwater
       Monitoring/Covering or Capping

 Alternative 3 consists of the following elements:
    •  removal and offsite treatment (offsite incineration) and disposal of soil containing
       nitroaromatic compounds greater than 100,000 mg/kg and lead above 450 mg/kg
       (approximately 270 cy);
 cnbotch-i6/rod-*/M/19/96                         40              Eitvinmmaaat Sdenct A E*gm*tmg. Inc.
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                                                    Crab Orchard National Wildlife Refae EMMA OV ROD
    •  additional removal of contaminated soils at Site COP-4 to depth of two feet below grade
       within the existing fenced area, with disposal of excavated soils at an offsite permitted
       special waste landfill (applicable to Alternative 3A only);
    •  sampling to ensure that remaining affected soil at Sites COC-3 and COP-4 does not exhibit
       the characteristic of RCRA hazardous waste for lead and 2,4-DNT;
    •  backfill excavated areas to shape the base of the covers;
    •  construction and maintenance of soil covers (Alternative 3A), multimedia (RCRA type)
       caps (Alternative 3B), or composite-barrier (RCRA) caps (Alternative 3Q over the
       remaining affected soil areas at Sites COC-3 and COP-4;
    •  groundwater monitoring at Sites COC-3 and COP-4;
    •  implementation of land use controls at Sites COC-3  and  COP-4; and
    •  long-term maintenance of the soil covers or caps for a period of up to 30 years.

Erosion control measures including installation of a temporary stormwater retention basin will be
implemented during cover/cap construction at Site COC-3 due to the gully that extends through
the northern end of me site. Permanent runon/runoff control measures will remain in place for
the life of me covers or caps.

The caps under Alternatives 3B and 3C will reduce the infiltration of surface water into the
affected soil by diverting it through the drainage layer. The combined thickness of the soil layers
and the use of a stone drainage layer will help reduce the potential risk of damage to die
geomembrane and greatly restrict dermal contact wtm the underlying affected soil.

83.1   SoU Covers (Alternative 3A)

The soil covers consist of (from the top down) 6 inches of topsoU to retain moisture and promote
the growth of vegetative cover, and 18 inches of clay-rich soil to support the root zone. Random
fill will be, placed over the  excavated area to shape me base of the cover and to  achieve the
desired grade. Soils with contaminants above remediation goals may be consolidated and  used as
random fill. The total m^kness of the covers (24 inches) will adequately prevent humans and
animals from  contacting affected soil.
    Capital Costs                     $3,468,000
    Present Worth  O&M Costs         $251,700
    Total Present Worth              $3,719,700
    Time to Construct                 8 months

8.3.2   Multimedia Caps (Alternative 3B)

The multimedia caps will consist of 72 inches of material containing (from the top down) topsoil
to retain moisture and promote the growth of vegetative cover;  clay-rich soil to  support the root
 cr«boccfa-«6/rod-«A>4/l9/96                          41'               Emironmntal Sdatct A Engineering. Inc.
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                                                  Crab Orchard National Wttfljfr Refuge EMMA OV ROD
zone; a drainage layer consisting of stones sandwiched between layers of geotextUe material; and
an impermeable geomembrane.  A layer of random fill will also be placed over the excavated
areas to shape the base of the cap and to achieve the desired grade.
    Capital Costs                   $4,046,600
    Present Worth O&M Costs        $290,300
    Total Present Worth             $4,366,900
    Time to Construct                 8 months

8.3.3   Composite4MUTier Caps (Alternative 3C)

The composite-barrier caps are comprised of 60 inches of material containing (from the top down)
topsoil to retain moisture and promote the growth of vegetative cover; clay-rich soil to support the
root zone; a drainage layer consisting of cobbles (3 to 6 inches in diameter) sandwiched between
two layers of geotextUe material; and an impermeable geomembrane followed by a clay barrier.
A layer of random fill will also be placed over the excavated areas to shape the base of the cap
and to achieve die desired grade.
  •   Capital Costs                   $4,139,500
     Present Worth O&M Costs         $290,300
     Total Present Worth             $4,429,800
     Time to Construct                 8 months

8.4  Alternative 4 — Removal/Land Use Controls/Groundwater
       Monitoring/Excavation/Oflsite Disposal/Backfill/Restoration

Alternative 4 consists of die following elements:
     • removal and oftsite treatment (offsite incineration) and disposal of soil containing
       nitroarornatic compounds greater than 100,000 mg/kg and lead above 450 mg/kg
       (approximately 270 cy);
     • excavation of remaining affected soils at Sites COC-3 and COP-4 to a depth of 5 feet
       (approximately 8,870 cy);
     - sampling to ensure mat remaining affected soil at Sites COC-3 and COP-4 does not exhibit
       the characteristic of a RCRA hazardous waste;
     • transportation and disposal of these soils to an offsite permitted special waste landfill;
     • backfill excavated area to grade;
     • restoration of site;
     • groundwater monitoring at Sites COC-3 and COP-4; and
     •  implementation of land use controls at Sites COC-3 and COP-4.
 cnborcb-(6/rod-^O4/l9/96                        42               Environmental Science Jk Engineering. Inc.
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                                                  Crab Orchard National WiUiife Refuge EMMA OV ROD
 Restoration of sites will include covering the backfilled areas with topsoil and revegetation.
    Capital Costs                   $4,193,000
    Present Worth O&M Costs         $193,300
    Total Present Worth             $4,386,300
    Time to Construct                8 months

8.5   Alternative 5 — Removal/Land Use Controls/Groundwater
       Monitoring/Excavation/Composting/BackfUl Composted
       Soil/Capping

Alternative 5 consists of the following elements:
    •  removal and offsite treatment (offsite incineration) and disposal of soil containing
       nitroaromatic compounds greater than 100,000 mg/kg and lead above 450 nog/kg
       (approximately 270 cy);

    •  excavation of affected soil to a depth of 5 feet (approximately 8,870 cy) from Sites COC-3
       and COP-4 for Alternative 5A;
    •  excavation of affected soil to a depth of 2 feet (approximately 3,550 cy) from Sites COC-3
       and COP-4 for Alternatives SB and 5C;
    •  sampling to ensure that remaining affected soil at Sites COC-3 and COP-4 does not exhibit
       the characteristic of a RCRA hazardous waste;
    •  subsequent treatment of this soil by composting to degrade the nitroaromatic compounds
       down to remediation goals;
    •  backfilling excavated areas with treated soils;
    •  site restoration;
    •  construction and maintenance of multimedia (RCRA-type) caps (Alternative 5B), or
       composite-barrier (RCRA) caps (Alternative 5C) over the remaining affected soil ?reas at
       Sites COC-3 and COP-4;
    •  groundwater monitoring;
    •  long-term maintenance of the c'ps (Alternatives 5B and 5Q for a period of up to
       30 years; and
    •  implementation of land use controls at Sites COC-3 and COP-4.

 Site restoration will consist of removal of the treatment equipment and structures, covering the
 area with topsoil, and revegetating for Alternative 5A, multimedia capping for Alternative 5B,
 and composite-barrier capping for Alternative 5C.
    Alternative 5A:
    Capital Costs                  $4,967,200
    Present Worth O&M Costs       $2,440.300
    Total Present Worth             $7,407,500
    Time to Construct                   3 years

 cnboreb-^/rod-^04/19/96                         43              Environmental Scienc* A Engineer**, htc.
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                                                   Crab Orchard National WUdt&i Refuge EMMA OU ROD
    Alternative SB:
    Capital Costs                    $7,222,500
    Present Worth O&M Costs       $1,584,900
    Total Present Worth             $8,807,400
    Time to Construct                   2 years
    Alternative 5C:
    Capital Costs                    $7,454,900
    Present Worth O&M Costs       $ 1,585,800
    Total Present Worth             $9,040,700
    Time to Construct                   2 years

8.6   Alternative 6 — Land Use Controls/Groundwater Monitoring/
       Excavatipn/On-site Incineration/Backfill Incinerated Soil/
       Restoration

Alternative 6 consists of the following dements:
    •  excavation of approximately 3,820 cy of affected soil to a depth of 2 feet;
    •  sampling to ensure mat remaining affected soil at Sites COC-3 and COP-4 does not exhibit
       the characteristic of a RCRA hazardous waste;
    •  incineration of this soil in a mobile on-site incineration unit;
    •  backfill of excavated areas with treated soil;
    •  site restoration;
    •  groundwater monitoring; and
    •  implementation of land use controls at Sites COC-3 and COP-4.

The mobile incineration unit will be transported in modular sections and men fully assembled at
the EMMA OU. Following incineration ?nd destruction of the nitroaromatic compounds in the
excavated soil, me residual ash will be tesusl to verify that it is below remediation goals prior to
using it as backfill  material.  Should the ash be characterized as a hazardous waste or exceed
remediation goals for lead, it will be disposed of properly.  Site restoration will consist of
removal of the treatment equipment and structures, covering the backfilled areas with topsoil, and
revegetating.  For the purpose of this cost estimate, it is assumed mat the residual ash will  not be
characterized as a hazardous waste.
    Capital Costs                   $8,129,600
    Present Worth O&M Costs        $193,300
    Total Present Worth             $8,322.900
    Time to Construct                10 months
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                                                   Crab Orchanl National WUdttfc Kefiige EMMA Oil ROD
8.7  Alternative 7 — Land Use Controls/Groundwater Monitoring/
      Excavation/Offsite Incineration/Backfill Soil/Restoration

Alternative 7 consists of the following elements:
    • excavation of approximately 3,820 cy of affected soil to a depth of 2 feet;
    • subsequent mixing of this soil for ease of handling;
    • sampling to ensure that remaining affected soil at Sites COC-3 and COP-4 does not exhibit
      the characteristic of a RCRA hazardous waste;
    • backfill excavated areas to grade;
    • transportation of the soil to an ofisite incinerator for incineration;
    • site restoration;
    • groundwater monitoring at Sites COC-3 and COP-4; and
    • implementation of land use controls at Sites COC-3 and COP-4.

The soil will be transported offsite by a licensed transporter to a permitted waste incinerator. Site
restoration will consist of covering the backfilled areas with topsoil, and revegetating.
    Capital Costs                  $10,545,500
    Present Worth O&M Costs         $ 193,300
    Total  Present Worth            $10,738,800
    Time  to Construct                8 months
 cnboreh-^cod-WO4/19/96                        45               Environment* Science A Engineering. Int.
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                                                   Crab Orchard National Wildlife Refuge EMMA OU ROD
         9.0  Summary of the Comparative Analysis of Alternatives

In accordance with the provisions set forth in CERCLA. SARA, and the NCP, each of the
alternatives was evaluated against nine established criteria.  Overall protection of human health
and the environment and attainment of applicable or relevant and appropriate requirements
(ARARs) are threshold criteria and the primary objectives of a remedial action.  In addition, the
selected remedial alternative must reflect the best balance among criteria such as reduction of
nitroaromatic compounds; short- and long-term effectiveness;  implenientability; and cost. Support
agency and community acceptance are also considered during the evaluation. These nine criteria
are as follows:
    Threshold Criteria
    •  Overall Protection of Human Health and the Environment determines whether an
       alternative eliminates, reduces, or controls threats to human health and the environment.
    •  Compliance with ARARs evaluates whether the alternative meets federal and state
       environmental laws pertaining to the site.
    Balancing Criteria
    •  Long-term Effectiveness and Permanence considers the ability of an alternative to
       protect human health and the environment over time.
    •  Reduction of Toxicity, Mobility or Volume Through Treatment evaluates an
       alternative's use of treatment to reduce die harmful nature of contaminants, their ability to
       move in the environment, and the amount of contamination present.
    •  Short-term Effectiveness considers the length of time needed to implement an alternative
       and die risks it poses for workers, residents, and the environment during implementation.
    •  Implementability considers the technical and administrative feasibility of implementing an
       alternative.
    •  Cost evaluates estimated capital and O&M costs, as well as present-worth costs.
    Modifying Criteria
    •  State Acceptance considers whether the IEPA and USFWS agree with the recommended
       alternative as presented in the ROD.
    •  Community Acceptance considers the public's response to the alternatives described in
       the FS and the Proposed Plan.  Specific responses to public comments are contained in the
       Responsiveness Summary attached to this ROD.

The seven alternatives are compared under die various evaluation criteria, profiling the
performance of the alternatives against the nine criteria.  A summary of this comparison is
provided in Table 9-1.
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                                                                                                                         Crab Onkard Mutono/ Wildly*
Table 9-1.  Remedial Alternative Evaluation Summary
                          I
                                 j:
                                              3A
                                                                        I*.
                                              3C
                                                         »•
                                                         I,
                                                              5A
                                                                             5C
Protective of Huinu
HMlth Mid E«vironmMi
CmnpliM wkfc ARAIU
Looi-Tcna
Reduction of Mobility
Reduction of Toiicily
Reduction of Volume
Sbort-Tenn Effectiveoew
Co*($M)
0.6
3.1
3.7
4.3
4.4
4.4
7.4
I.I
9.0
8.3
                                                     10.7
PuWic
Sate Acceptu
   crtbuKb-t6/ibl9-l 01/07/96
                                                                                                                     Environmental Scicnci A Enginetrini, Inc.
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                                                     Cnb Orchard National WttfljfSr Rejkge EMU OU ROD
9.1   Overall Protection of Human Health and the Environment

No active mitigation processes are implemented under Alternative 1 (No Action). Alternative 1
provides limited protection to human health and the environment through natural processes (i.e.,
leaching, dilution, and chemical and biological degradation).

Alternative 2 (Removal/Fencing/Land Use Controls/Groundwater Monitoring) provides greater
protection of human health than Alternative 1 through removal of soil with nitroaromatic
compound concentrations greater than 100,000 mg/kg and implementation of land use controls
and fencing to limit physical access by humans and animals to the remaining affected soil.
However, Alternative 2 will only provide limited protection to human health and the environment
Soil with unacceptable carcinogenic, non-carcinogenic, or ecological risks would be accessible for
direct contact and ingestion by humans and animals if the fencing is breached.

Alternatives 3 through 5 provide for the excavation and removal of soil with nitroaromatic
compound concentrations greater than 100,000 mg/kg and lead greater than 450 mg/kg.
Alternatives 6 and 7 provide for the incineration of affected soils to a depth of 2 feet from grade.
Alternatives 3, SB, and SC provide a minimum of two feet of cover or capping over backfilled
soil containing contaminants above remediation goals. Alternatives 4, SA, 6,  and 7 provide 6
inches of topsoil and seeding over two feet (5 feet for Alternatives 4 & SA) of backfilled material
containing either treated soil from composting (Alternative SA), treated soil from incineration
(Alternative 6), or clean soil (Alternatives 4 and 7).  The remedial action objective of prohibiting
human contact and minimizing wildlife contact with the affected soil would be met by the
installation of soil covers or caps. Although the site contaminants still remain in the soil, the
backfilled materials and soil covers or capping installed under the above alternatives will eliminate
the pathway that presents potential unacceptable risks to human health and the environment 0.e.,
direct contact).   '• hus, the  protective benchmarks  of  1 .OE-06 and HI/ERI < 1 are met The
likelihood of the affected soils ever being exposed to the surface in quantities  that pose
unacceptable risks is low when covers/caps are placed over the affected areas  and maintained.
Thus Alternatives 3 through 7 provide equal degree of overall protection of human health and the
 environment. Alternative  SA will provide slightly lesser degree of protection to potential
 ecological receptors man Alternatives 3, 4, SB, SC,  6 & 7, if the backfilled soil (treated material
s
 from composting) under 6 inches of top soil does not meet remediation goals.

 The RI/BRA evaluated the fate and transport of constituents of concern including the potential
 transport of constituents in groundwater to surface water.  The BRA evaluated the potential
 ecological risk to aquatic receptors and determined that Sites  COC-3 and COP-4 did not pose a
 potential unacceptable risk to aquatic receptors.
 cnborch-i6/rod-«/04/19/96                          48               Environmental Sciene* A Engineering. Inc.
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                                                   Oaft Ordtard National miiB& Refuge EMMA OU ROD
It may be necessary to remove existing trees during implementation of Alternatives 2 through 7.
Every effort will be made not to cut trees during breeding and nesting season for residential and
migratory wildlife.  Any cutting of trees will be done in consultation with USFWS.

9.2   Compliance with ARARs

Compliance with chemical-specific ARARs, specifically 35 Illinois Administrative Code (LAC)
Part 620 (Illinois Groundwater Quality Standards), will be achieved by each of die
alternatives because concentrations of nitroaromatic compounds and metals in shallow
groundwater will not exceed these standards.  Although to be considered (TBQ values for
nitroaromatic compounds in groundwater were calculated by EPA, these values are not
promulgated standards such as MCLs. Therefore, these concentrations are not chemical-specific
ARARs (see Appendix B of the FS Report). Because shallow groundwater is not currently used
as a drinking water source, nor is it expected to be used in the foreseeable future, a complete
exposure pathway does not exist. Therefore, no unacceptable risk to human health exists.  In
addition, removal of soils containing greater man 100,000 mg/kg nitroaromatic compounds and
lead above 450 mg/kg will occur under each alternative except the No Action alternative.  Thus,
Part 620 has been addressed.

Location-specific ARARs will be attained by each of the alternatives considered.  Actions taken as
part of the active treatment alternatives (Alternatives 2 through 7) will comply with the
corresponding potential action-specific ARARs. Additional treatment of residual waste streams
may potentially be required in order to comply with land disposal restrictions.

Action-specific ARARs will be met under Alternatives 2 through 7 by confirmation sampling of
the excavations to ensure mat soils remaining on-site do not exhibit me characteristics of a RCRA
hazardous waste*.

The chemical-, location-, and action-specific ARARs evaluated are presented in Section 2.0 of the
FS Report. Those ARARs that apply specifically to Alternative 3A are identified in Section 11.

9.3    Long-Term Effectiveness

Because no treatment technologies have been proposed under Alternatives 1 and 2, nitroaromatic
compounds and metals will be present above remediation goals in the affected soils for some time.
Under each of the alternatives, the nitroaromatic compounds will degrade over time due to natural
attenuation.  The extent to which natural attenuation will reduce potential risks is unknown. Land
use controls and fencing in Alternative 2 will restrict the use of the EMMA OU sites and potential
access to the remaining nitroaromatic compounds and metals in the soil, thus reducing the
potential for the pathway presenting an unacceptable risk (direct contact) to be completed.
 cr»bocch-«6/rod-«/O4/19/96                         49               Environmental Science A Engineer**. Inc.
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                                                    Crab Orchard National Wildlife Refuge EMMA OV ROD
Alternatives 3 through 7 will provide an equal degree of long-term effectiveness by further
reducing die potential for direct contact with oitroaromatic compounds and metals in soil through
the construction of covers or caps or .increased excavation depth over the affected areas.
Alternative 5A will provide a slightly lesser degree of protection to potential ecological receptors
than Alternatives 3, 4, SB, 5C, 6, and 7, if the backfilled soil (treated material from composting)
under 6 inches of top soil does not meet remediation goals.

9.4   Reduction of Mobility, Toxicity, or  Volume Through
       Treatment

Alternative 1 does  not include any removal, containment, or treatment actions. Therefore, no
reduction in mobility, toxicity, or volume will be attained.

Alternatives 2 through 5  include the removal  and treatment (offsite incineration) of soil containing
nitroaromatic compounds greater man 100,000 rag/kg.  This will result in a significant reduction
in the mobility, toxicity,  and volume of nitroaromatic compounds and lead.  In addition,
Alternative 5A includes removal and treatment through composting of remaining affected soils to
a depth of 5 feet.  Alternatives SB and SC also include removal and  treatment (by composting) of
remaining affected soils to a depth of 2 feet.  Alternatives 6 and 7 include removal and treatment
(by incineration) of affected soil to a depth of 2 feet. Thus, Alternative SA will provide the
greatest reduction in mobility, toxicity, and volume through treatment followed by Alternatives
SB, SC, 6, and 7.  Alternatives 3 and 4 will provide a slightly lesser degree of reduction in
mobility, toxicity and volume through treatment man Alternatives S, 6, and 7.  However,
Alternatives 3A and 4 provide for additional  reduction (without treatment) in mobility, toxicity,
and volume through removal  and offsite disposal of remaining affected soil above remediation
goals.  Alternative 3A  includes removal and offsite disposal of remaining affected soil to a depth
of ? feet within the existing fenced area at Site COP-4.  Alternative  4 includes removal and offsite
disr jsal of remaining affected soil to a depth of 5 feet.
 9.5    Short-Term Effectiveness

 Since no active treatment technologies are employed in Alternative 1, there are no safety concerns
 associated with the implementation of this alternative. Implementation of Alternative 1 is not
 considered to increase the potential risk to the community and presents tile least amount of
 potential exposure to workers, the community, and the environment during remedial activities.

 Implementation of Alternatives 2 through 7 is likely to result in potential exposure of remedial
 workers to affected soil and dust particles generated during removal, treatment,  transport, and/or
 containment processes. However, proper safety procedures are expected to ensure that the
 workers and the community are not subjected to any unnecessary risk from exposure to airborne
 cnboKh-t6/rod-a/04/19/96                          SO               Environmental Science A Engineering. Inc.
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                                                    Crab Orchard National WUtUfc Refuge EMMA OU ROD
contaminants.  The significant distance that exists between the EMMA OU sites and the Crab
Orchard NWR property line will help to ensure that airborne contaminants do not the reach the
community. Cattle fanners will still have access to pastureland adjacent to the sites. Handling of
the site soils will potentially present safety hazards to on-site workers due to the presence of
nitroaromatic compounds. This will be addressed through use of magnetic surveys in combination
with a hazards analysis of equipment and procedures prior to excavation, capping or treatment
activities.  Recommendations on equipment and procedural modifications resulting from the
hazards analysis will be carefully followed to ensure worker safety.  These alternatives also
involve the operation of heavy equipment, creating an on-site safety concern for remedial
workers.  Prudent safety  procedures, the use of appropriate personal protective gear, use of a
hazards analysis, and the development and implementation of a site safety and health plan will be
sufficient to protect workers during remedial operations.

Alternatives 2, 3, 4,  5, and 7 present an increased exposure to the community due to the necessity
for hauling affected soil through surrounding areas for offsite disposal.  However, proper safety
procedures taken during transportation will ensure that the surrounding community is not affected.

Of the action alternatives (Alternatives 2 through 7), Alternative 2 is anticipated to have the
greatest short-term effectiveness because it does not involve repeated handling of the affected soil.
Alternative 3 will have a greater degree of short-term effectiveness than the  remaining alternatives
due to the minor amount of handling of nitroaromatic containing soil during implementation.
Alternatives 4 through 7  are considered to have a lesser degree of short-term effectiveness
because of the greater degree of soil manipulation through excavation, transportation, storage, and
treatment. Alternatives 4 and 7 present an increased exposure to the community due to me
necessity for hauling large volumes of affected soil through surrounding areas  for offsite disposal.
The remaining alternatives (5 and 6) have lesser short-term effectiveness due to the extensive
on-site soil handling required and the remedial action time frames.  Alternative 6 requires less
time to meet remediation goals (4 to 7 months) man does Alternative 5  (2 years).

9.6   Implementation

Alternative 1 employs no active remedial measures and,  therefore, has no technical difficulties
associated with it. Land use controls, groundwater monitoring, and fencing in Alternatives 2
through 7 would be  easily implemented.  Land use controls may limit management options for
Sites COC-3 and COP-4.

Implementation of Alternatives 2 through 7 will require the imposition of land use controls. For
Alternative 2, placement of wells, subgrade activities, and pond creation within the perimeter  of
the soil covers on Sites COC-3 and COP-4  will be restricted. New  chain-link fences will be
constructed at Sites COC-3 and COP-4 under Alternative 2.  For Alternatives 3 through 7, a
restriction on the placement of wells, subsurface activities, and pond creation will only extend

crabofch-rf/rod-*/04/19/96                         51               Enwonmaual Science A Engineering. Inc.
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                                                     Crab Orchard National Wildlife Refitge EMMA OU ROD
over the covered, capped, or backfilled areas of Sites COC-3 and COP-4. For Alternatives 3
through 7, there are no anticipated adverse effects on the recreational purposes of the GOC area
of the EMMA OU because current and planned management practices do not require the use of
groundwater and are not invasive to soil. Current management practices do not allow visitor
access to die COP area of the EMMA OU. The removal of fencing and the establishment of
native grasses after completion of Alternatives 3 through 7 will provide habitat for indigenous
species as well as permit big game hunting and guided and self-guided wildlife trails.  Thus, the
implementability of Alternatives 3 through 7 is enhanced over Alternatives 1 and 2 because they
will allow the USFWS greater management flexibility.

The implementability of Alternatives 2, 3, 4, 5 and 7 are minimally affected by the necessary
transport of affected soil through the surrounding community. However, potential safety hazards
posted by the transportation of affected soil will be mitigated through the use of proper safety
procedures such as DOT requirements, preferred traffic routes, and advance notice to emergency
services.  Construction and excavation activities in Alternatives 3 through 5 are expected to occur
Without technical difficulties as materials and equipment necessary for cover or cap construction
and excavation and backfill are readily available.  Tree/brush clearing to allow access of heavy
equipment to the affected soil areas and construction during the dry summer months are
prerequisites to implementation of Alternatives 3 through 7.

Alternative 5 will require special equipment and operators to implement the composting treatment
process.  However, personnel, equipment, and materials are available from vendors.  In addition.
Alternative 5 may present the most difficulty with regard to soil handling due to the greater
manipulation of soil.  A pre-design stage and/or a treatability study of the effectiveness of the
composting treatment will be required under Alternative 5. The remedial technology of
incineration (offsite and onsite) is technically feasible. Both commercial and mobile incinerators
are readily available.  Alternatives 6 and 7 can be implemented without much difficulty.
However, a trial bum test is required for onsite incineration under Alternative 6. Each of the
alternatives involving excavation of soil may potentially present technical difficulties due to the
clayey nature of the EMMA OU site soils. Clays and silts will tend to clog equipment and impait
equipment activity, which may result in longer treatment times due to extended handling
activities.

9.7    Cost

The costs of the alternatives were evaluated.  Alternatives 1 and 2 are the least costly of the
alternatives.   However, Alternative 1 provides no active remediation processes.  Active remedial
processes associated with Alternative 2  consist only of the excavation of soil with greater than
 100,000 mg/kg  nitroaromatic compounds.  Passive processes implemented under Alternative 2
include fencing, groundwater monitoring, and land use controls.  Of the remaining alternatives
that do provide  for active remediation processes (Alternatives 3 through 7), Alternatives 3A, 3B,

craborch-«&/rod-«/D4/l9/96                          52                Environmental Science t Engineering. Inc.
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                                                    Crab Orchard National Wttttyfe Keftige EMMA OU ROD
3C, and 4 are similar in cost ranging from $3.7 million for 3A and increasing with each
alternative to $4.4 million for Alternative 4. Alternatives 5A, SB, SC, and 6 are also similar in
cost ranging from $8.3 million for Alternative 6 to $9.0 million for Alternative SC.  Alternative 7
(Offsite Incineration) is the most costly of the alternatives at $10.7 million. The costs associated
with each of the alternatives are presented in Table 9-1.

Each of the Alternatives 3 through 7 meet the criteria for protection of human health and the
environment, and are accepted by the state as viable treatment alternatives. In addition, each of
these alternatives also meet the requirements for compliance with ARARs; long- and short-term
effectiveness; implementabUity; and the reduction of MTV for the nitroaromatic compounds.
Although each of the Alternatives 3 through 7 meet the seven threshold criteria, Alternative 3A is
the least costly of these alternatives. Therefore, Alternative 3 A is the most cost effective.

9.8   State and Support Agency Acceptance

IEPA has stated that Alternative 3A would be an acceptable remedial alternative for the
EMMA OU. The USFWS also concurs with Alternative 3A as the selected remedy.

9.9   Community Acceptance

The concerns raised by the public during the public comment period are summarized  in the
Responsiveness Summary (Appendix A).  Based on public comments received both verbally at the
public meeting and  through letters during the public comment period, the public appears to concur
with Alternative 3A as the selected remedy.
 cnbocch-f6/rod-«AM/19/96                          S3               Ennronmaaat Science A EngMetrutg. lite.
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                                                    Crab Orchard National Wildlife Refuge EMMA OU ROD
                               10.0  Selected Remedy

Based on careful consideration of the technical, environmental, institutional, public health and cost
criteria, and in keeping with the overall response strategy, the selected remedial alternative is
Alternative 3A.  Alternative 3A consists of removal and treatment of soil with concentrations of
nitroaromatic compounds greater than 100,000 mg/kg and lead greater than 450 mg/kg
(approximately 270 cy) at Sites COC-3 and COP-4; the removal of nitroaromatic compounds in
soil at Site COP-4 to a depth of 2 feet below grade within die existing fenced area; further
removal and offsite disposal of soil shown by TCLP analysis to match die RCRA definition of a
characteristically hazardous waste (2,4-DNT greater than 0.13 mg/L and lead greater than
5 mg/L) at both  Sites COC-3 and COP-4; construction and long-term maintenance of soil covers;
land use controls; and groundwater monitoring.

10.1  Detailed Description of the Selected Remedy

The following elements are necessary for implementation of Alternative 3A:
    •  excavation and offsite treatment and disposal (offsite incineration) of soil at Sites COC-3
       and COP-4 with concentrations of nitroaromatic compounds greater man 100,000 mg/kg
       and lead  greater than 450 mg/kg (approximately 270 cy);
     •  soil above 100,000 mg/kg will be rendered safe prior to transport offsite to a commercial
       incinerator; and
     •  Additional removal of RDX/HMX contaminated soil at Site COP-4 to a depth of 2 feet
       below grade within the  existing fenced area, with disposal at an offsite permitted special
       waste landfill;
     •  sampling to ensure that remaining affected soils at Sites COC-3 and COP-4 do not exhibit
       die characteristics of a RCRA hazardous waste for lead and 2,4-DNT.

After the removal of soil with greater man 100,000 mg/kg nitroaromatic compounds and lead
greater man 450 mg/kg, and the additional removal of soils to a depth of 2 feet below grade
within the fenced area at Site COP-4, the following elements will be implemented:
     •  backfill of excavations to shape the base of the covers;
     •   me construction and maintenance of soil covers over the remaining affected soil areas at
        Sites COC-3 and COP-4;
     •   groundwater monitoring;
     •   land use controls at Sites COC-3 and COP-4; and
     •   long-term maintenance  of the soil covers.

Land use controls will only be implemented at Sites COC-3 and COP-4. These land use controls
include restrictions of the following activities: groundwater well installation; subgrade activities;
and pond creation within the perimeter of the soil covers on Sites COC-3 and COP-4.
 cnboKfc-«6/rod-*/04/19/96                         54              Emtrtmrnaaal Science A Engineering. Inc.
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                                                     Crab Orchard National WiMfe Refuge EMMA OU ROD
Removal of trees, brush, fencing, and other debris within the areas to be excavated during soil
removal, as well as location and removal of unexploded ordnance (UXO), may be necessary prior
to startup of soil removal activities.

The soil covers consist of (from the top down) 6 inches of topsoil to retain moisture and promote
vegetation and 18 inches of clay-rich soil to support the root zone.  Random fill will be placed
over the excavated areas.  Soils with contaminants above remediation goals  identified in
Table 10-1 may be consolidated and used as random fill along with  native soils.  The purpose of
the random fill is to bring the excavated areas to the desired grade prior to installation of the soil
cover.  The random fill material will consist of native soils, and may include consolidated
materials.  A typical cross-section of a soil cover is represented in Figure 10-1.

The soil covers will cover the areas containing soils with contaminants above the remediation
goals.  At Site COC-3,  the area to be covered  is approximately 71,500 square feet (sq ft).  At Site
COP-4, the area to be covered is approximately 4,900 sq ft.  The total square footage of the areas
to be covered is approximately 76,400 sq ft  A stonnwater retention basin will be placed along  •
the perimeter of the cover at Site COC-3 to control runoff during construction of the soil covers.
Long-term control of stonnwater runoff will be implemented by erosion control methods such as
sloping and drainage swales. Upon completion of the covers, a vegetative cover will be
established to prevent cracking  and erosion caused by wind and water.

Land use controls will be implemented at Sites COC-3 and COP-4 to reduce potential  future
exposure to the remaining affected soil and restrict the construction of drinking water wells in the
EMMA OU.  These land use controls will include restrictions of the following activities:
groundwater well installation, subgrade activities, and  pond creation within the perimeters of the
soil covers at Sites COC-3 and  COP-4. Groundwater monitoring will be conducted at Sites
COC-3 ^nd COP-4.  The final groundwater monitoring program will be developed during design
as part of the O&M plan.

The estimated capital cost of the selected remedy is $3,468,000.  The estimated present worth
operations and maintenance cost is $251,700, and the estimated net present worth cost is
$3.719,700. These costs are detailed in Table 10-2.

 10.2  Rationale  for Selection

 After careful consideration of die technical, environmental, institutional, public health, and cost
 criteria, the selected  remedial action alternative for the Crab Orchard NWR EMMA OU sites is
 Alternative 3A (Removal/Land Use Controls/Groundwater Monitoring/Soil Covers).
 Implementation of Alternative 3A will achieve the remedial action objective for the Crab Orchard
 NWR EMMA OU sites by minimizing the potential human health and ecological risks associated
 crabofch-«6/rod-«/04/19/96                          55               EmvonmeMut Science A E*fi*eti+t. Inc.
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                                                    Crab Orchard National Wildtyc Refuge EMMA OU ROD
 Table 10-1.   Remediation Goals for EMMA OU Soil (rag/kg), Crab Orchard NWR. Marion,
              Illinois	

      Contaminants	Remediation Goal	         Basis*

 Nitroaromatics

   TNT                               2.11                            PQL

   1,3,5-TNB                          2.25                            PQL

   HMX                              4.19                            PQL

   RDX                               4.13                            PQL
 Metals

   Lead                                450                     MAOU and PCB OU
	Remediation Goal	

* The nitroaromatics remediation goals are based on die current Practical Quantitation Levels
  (PQLs).  PQLs are generated by the laboratory based on site-specific samples/information.  In
  the case of die EMMA OU sites, enough data are available to provide PQLs based on analytical
  results from the site. These PQL values are higher than die estimated method quantitation
  limits (QLs) due to matrix interferences and other laboratory instrumentation interferences from
  the soils (clays) at the EMMA OU sites. The estimated method QLs are developed under
  "ideal" situations (sands), where extraction and analysis are optimal.

PQL  - Practical quantitation level.

Source: ESE, 1995.
cnborch-*6/rod-«/04/19/96                         56               Environmental Science A Engineering. Int
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                        Iff CLAt'-RICH SOIL
                  RANDOM FILL TO ESTABLISH
                 BASE GRADE (DEPTH VARIES)
Figure  10-1
CLAY AND SOIL COVER
CRAB ORCHARD NWR-MARION ILLINOIS
ESE
cence ft
£«gi«eeriag. Inc.
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                                                    Crab Orchart National Wilttltfe Kffuge EMMA OV ROD
 Table 10-2.  Estimated Costs of Selected Remedy—Alternative 3A	
                             Capital Costs	Estimated Cost
 Treatment Component
   Mobilization/Demobilization                                                 $42,690
   Fence Removal and Land Use Controls                                         $9,450
   Soil Covers                                                               $374,120
   Excavation/Soil Staging                                                    $125,210
   Removal of Soils with Greater than 100,000 mg/kg Nitroaromadc              2,190,000
   Compounds and 450 mg/kg Lead
   Subtotal Capital Costs                                                     $2,741,470
   Engineering — 10 percent of Subtotal                                        $274,150
   Contingency — 15 percent of Subtotal                                       $452,340
 Total Capital Cost                                                          $3,467,960
 Operations and Maintenance Cpsts
   Ground water Monitoring                                                   $260,910
   Cover Maintenance                                                          $3,800
 Total Costs
   Net Present Worth Using a 5 Percent Discount Value for 30 Years	$3,719.700
cnborct>-i6/rod-«/D4/l9/96                          58               Environmental Science A Engineering, Inc.
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                                                    Crab Orchard National WUd%e Kffttge EMMA OU ROD
with site contaminants present in die soil above remediation goals. Because the BRA showed
potential unacceptable risk to ecological receptors, preliminary remediation goals were calculated
for their protection. These preliminary remediation goals were below PQLs, and were therefore
unquantifiable and unachievable by any of the alternatives. In addition, since the TBC values are
below PQLs, they cannot be reliably measured. Therefore, the PQL is used as a remediation
goal. Remediation goals have been set at the PQL for nitroaromatic compounds and 450 mg/kg
for lead at the sites (see Table 10-1).  The areas where soil exceeds remediation goals at
Sites COC-3 and COP-4 are presented in Figures 10-2 and 10-3, respectively.  For safety
reasons, it is necessary to remove soils with levels of nitroaromatic compounds above
100,000 mg/kg.  Additional removal of soils will take place within the fenced area at Site COP-4
to manage the potential risks at Sites COC-3 and COP-4 similarly. The potential detonation
hazards associated with the 100,000 mg/kg (or 10 percent) levels are based on an Army report
titled Testing to Determine the Relationship Between Explosi^y CofltffnJTlfltffd Sludge Components
and Reactivity. Army Environmental Center Report Number AMXTH-TE-CR-86096,
January 1987, which is contained in the Administrative Record.

Exposure to site contaminants of concern (nhroaromatics and lead) will be effectively eliminated
through implementation of this alternative thus attaining the protective benchmarks of l.OE-06 and
HI/ERK1. While covers are not considered irreversible, the technical feasibility and potential
cost of reversing the cover process will likely provide sufficient disincentive for removal of the
covers from the sites. With proper maintenance, the covers will provide adequate protection of
human health and the environment by preventing human contact and minimizing animal contact
with contaminants of concern.

Although not the least costly alternative, Alternative 3A  provides sufficient protection of public
health and the environment and  complies with identified ARARs. This alternative provides for
active treatment of affected soil t  x>ugh combination with the removal of those affected soils
containing concentrations of nitroaromatics greater than  100,000 mg/kg and lead above
450 mg/kg, and removal of soils to a depth of 2 feet below grade within the fenced area of Site
COP-4. This alternative also provides comparable environmental and public health protection as
the other alternatives considered through elimination of potential risks associated with direct
contact by humans and animals. This alternative meets USEPA's statutory preference for
treatment.

CERCLA Section  120(h)(3)(B) requires that, if the property is sold or transferred, each deed
contain language stating that action to protect human health and the environment has been taken
before the date of property transfer.  Implementation of grbundwater monitoring at locations
chosen to provide early indication of changing conditions will provide a warning system in case of
shallow groundwater migration.
 cnbof
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 C: /CT»a-OC/S J/COC3-PRC. OCN
                              *.J
                                             HAMPTON
                                             CEMETERY
                                                           0  - 75'  150'
                                                     LEGEND
                                                    	  ORA IMAGE*AY
                                                             EXISTING BARBED
                                                             WIRE FENCE

                                                             AREA OF SOIL
                                                             EXCEEDING
                                                             REMEDIATION COALS
Figure 10-2
EXTENT OF SOILS WITH  CONSTITUENTS OF
CONCERN  EXCEEDING
REMEDIATION GOALS
SITE COC-3
CRAB ORCHARD NWR  - MARION. ILLINOIS

                                   60
E5E
Environment*}
Science &
Engineering, Inc.
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  C:/OCM-LBK/OUa-ORC/TLM-COP*. OCM
           OF .SOIL CICCCOINC
        MElCDIATION
.
Figure  10-3
EXTENT OF SOILS WITH CONSTITUENTS
OF  CONCERN  EXCEEDING
REMEDIATION GOALS
SITE  COP-4
CRAB ORCHARD NWR  - MARION. ILLINOIS
ESE
Environment*!
Science &
Engineering. Inc.
                                    61
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                                                  Crab Orchard National Wildlife Refuge EMMA OU ROD
                         11.0  Statutory Determinations

To comply with the requirements of Section 121 of CERCLA. as amended by SARA the selected
remedy must satisfy the following statutory requirements:
  • Protect human health and the environment;
  • Comply with ARARs;
  • Be cost effective;
  • Utilize permanent solutions and alternative treatment or resource recovery technologies to the
    maximum extent practicable; and
  • Satisfy the preference for treatment as a principal element, or provide an explanation as to
    why this preference is not satisfied.

The implementation of Alternative 3A satisfies the requirements of CERCLA, as amended by
SARA, as detailed below.

11.1  Overall Protection of Human Health and the  Environment

Implementation of Alternative 3A will provide for the overall protection of human health and the
environment at Sites COC-3 and COP-4.  Of those complete exposure pathways evaluated  in the
BRA (ESE, 1994), soil removal and subsequent covering of the remaining affected soil will
eliminate the human exposure pathways of soil ingestion, dermal adsorption, and dust inhalation
at both sites.  Therefore, by preventing direct contact by humans and animals with contaminants
above remediation goals, any potential unacceptable risks from the affected soils to human health
and the environment would be mitigated, thus attaining the protective benchmarks  of l.OE-06 and
HI/ERK1.  The implementation of land use controls and O&M of the soil cover will prevent any
compromise of the integrity of the soil cover.

The BRA indicated that Site COC-4 poses a potential ecological risk to the bobwhite ^uail, while
not posing any unacceptable risk to human health. Potential ecological risks associated with
Site COC-4 are several orders of magnitude lower man  the potential risks at Sites  COC-3 and
COP-4 and will be further evaluated.

It may be necessary to remove existing trees during  implementation of the remedy. Every effort
will be made not to cut trees during breeding and nesting seasons for residential and migratory
wildlife. Any cutting of trees will be done in consultation with USFWS.

11.2  Compliance with ARARs

The selected alternative will comply with federal and state ARARs. A listing of ARARs
associated with the selected alternative is found on Tables 11-1  and  11-2.  The following ARARs
will be attained.
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                                                   Crab Orchard National VtidJife Refuge EMMA OU ROD
 Table 11-1.  Location-Specific ARARs for the EMMA OU Sites, Crab Orchard NWR, Marion.
             Illinois
 Resource Conservation Recovery Act (RCRA) Location Standards (40 CFR 264.18)

 Executive Order 11990 - Protection of Wetlands

 Subpart 404, Gean Water Act (40 CFR 230)

 Endangered Species Act (16 USC 1531, SO CFR 200, SO CFR 402)

 Migratory Bird Treaty (16 CFR Chapter 7)

 The Archaeological and Historic Preservation Act (16 USC 469)

 National Wildlife Refuge System Administration Act (16 USC 668, 50 CFR 27)

 Human Skeletal Remains Protection Act (Illinois revised statutes 1989, ch. 127, pars. 2661
 etseq.)

 Crab Orchard  National Wildlife Refuge Creation (61 Stat. 770 dated Aug 5. 1947)


Source:  ESE, 199S.
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                                                         Crab Orchard National Wildlife Refuge EMMA OV ROD
 Table  11-2.  Final and Potential Action-Specific ARARs for EMMA OU Sites, Crab Orchard
	NWR, Marion, Illinois	
         Action
              Citation
                                                                          Comment*
 Final Action Specific ARARs
   Excavation              40 CFR 264.114
   Generation of
   Hazardous Waste
40CFR61 SubpartM

40 CFR Part 262

40 CFR Part 261 Snbput C
   Illinois Special Waste    35 IAC 808 and 35IAC 809
   Requirements
   Offsite Transport        40 CFR Part 262 Subpart C

                          49 CFR Parts 171 through 179


                          40 CFR Part 263
                         49 CFR Parts 107. 171-177


  Worker Safety (OSHA)   40 CFR 1910.120

Potential Action-Specific ARARs

  Illinois Discharge        35 IAC 309
                          35 IAC 307

                          35 IAC 302
                                                             Disposal or decontamination of
                                                             equipment, structures, and soils

                                                             NESHAPS, asbestos air emissions

                                                             Establishes f^Ti^^rrf* for generators of
                                                             hazardous waste in general

                                                             Requirements for determination of
                                                             characteristic hazardous wastes

                                                             Non-RCRA wastes that pose a low or
                                                             moderate degree of public health during
                                                             their transportation, storage, treatment,
                                                             or disposal.

                                                             Pro-transport requirements
                                                                           «"«*»"«l« transport
                                     DOT
                                     regulations
                                          ifhft f*«"<<«fyi« that apply to
                                                               persons transporting hazardous waste
                                                               within the U.S. if the transportation
                                                               requires a manifest under 40 CFR Part
                                                               262

                                                               Regulates transportation of hazardous
                                                               materials

                                                               Regulates worker health and safety
                                     Implements National Pollution Discharge
                                     Elimination System (NPDES)

                                     Establishes effluent requirements

                                     Regulates direct discharge to offsite
                                     surface water
Note:  DOT    =  Department of Transportation
       OSHA   =  Occupational Safety and Health Administration

Source:  ESE,  1995.
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                                                    Crab Orchard National VRUSft Refuge EMMA OV ROD
Chemical-soecific-This alternative will comply with Illinois Groundwater Quality Standards (35
I AC Part 620) because contaminant concentrations in shallow groundwater are not above these
standards. Shallow groundwater at the EMMA OU sites is not currently used for drinking water
nor is it expected to be used in the foreseeable future.

Location-specific-The Endangered Species Act and Migratory Bird Treaty will be met under mis
alternative by implementing proper procedures to protect wildlife during excavation of soil.
Efforts will be made during excavation and construction of the soil staging area to minimi^ any
adverse effects on potential wetlands in order to comply with Executive Order 11990-Protection
of Wetlands and Section 404 of the Clean Water Act. Actions will be taken to comply with the
Human Skeletal Remains Protection Act if human skeletal remains are exhumed during excavation
activities.  Because Native American artifacts have been discovered on the refuge, actions will be
taken to comply with the Archaeological and Historic Preservation Act [40 CFR 6.301 (c)J.
Excavation will stop if Native American artifacts or human skeletal remains are discovered during
this remedial alternative. This alternative will be compatible with the major purposes for which
the refuge was established under the National Wildlife Refuge System Act (NWRSA) including
development and disposition consistent with the needs of agriculture, industry, recreation, and
wildlife conservation.

Action-specific-Active remediation of Sites COC-3 and COP-4 will be implemented through
removal of soils with greater man 100,000 mg/kg  nitroaromatic compounds and lead above
450  mg/kg for offsite disposal, and confirmation sampling of the excavated areas to ensure that
characteristically hazardous wastes do not  remain on-site. This alternative will be designed to
fulfill action-specific ARARs for die site.  Soil is likely to be determined a hazardous waste under
this  alternative, the RCRA equipment decontamination and soil disposal requirements contained in
40 CFR 264.114 will be complied with for excavation activities under mis alternative. The
requirements of 40 CFR 263 that apply to transportation of hazardous wastes will also be met. In
addition, Illinois special waste requirements (35 IAC 808 and 809) is applicable to  the disposal of
soils contaminated with  nitroaromatic  compounds less than or equal to  100,000 mg/kg in an
offsite permitted special waste landfill.

11.3  Cost-Effectiveness

Although not the least costly alternative, Alternative 3A provides a greater degree of long-term
effectiveness, and  provides larger reduction in the toxicity, mobility, and volume of contaminants
than Alternative 2. Among Alternatives 3 through 7. which provide equal degrees of protection
of public health and the environment, Alternative  3A is die least costly. Therefore, Alternative
3A is selected as the remedy that would provide the greater balance of long-term effectiveness;
implementability; reduction of toxicity, mobility, or volume; and cost.
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                                                  Crab Orchard National WUM&e Refiige EMMA OV ROD
11.4 Use of Permanent Solutions and Alternative Treatment
      Technologies or Resource Recovery Technologies to the
      Maximum Extent Practicable

Alternative 3A represents the best combination of a permanent solution and cost effectiveness
through the excavation, removal, and offsite treatment (offsite incineration) of soil containing
nitroaromatic compounds greater than 100,000 mg/kg. At Site COP-4, additional soil with
nitroaromatic compounds less than or equal to 100,000 mg/kg will be removed to a depth of
2 feet from grade and disposed of in an offsite permitted special waste landfill.  The remaining
soil above remediation goals will be covered with 24 inches of clean soil to protect human health
and wildlife.
11.5  Preference for Treatment as a Principal Element

Containment of materials by the use of a soil cover is considered a reliable remediation method
when augmented with land use controls. Removal and offsite treatment of those soils with
concentrations of nitroaromatic compounds above 100,000 mg/kg and lead above 450 mg/kg, and
covering of the remaining affected soil under Alternative 3A adequately addresses the statutory
preference for treatment as a principal element.

In summary, the selected remedy for Sites COC-3 and COP-4 is protective of human health and
the environment, complies with federal and state environmental requirements that are legally
applicable or relevant and appropriate to the remedial action, and is cost effective.  This remedy
uses permanent solutions, to the maximum extent practicable.  Because the remedy  will result in
hazardous substances remaining on-site, a review will be conducted within 5 years after
commencement-of remedial action to ensure that the remedy ">ntinues to provide adequate
protection of human health and the environment.
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                                                    Crab Orchard National Wildlife Refuge EMMA OV ROD
                                 GLOSSARY OF TERMS

Administrative Record:  A file that contains the information used to make a decision on the
selection of a response action under CERCLA.  The file is established at or near a site and is
available for public review.

Ambient Water Quality Criteria (AWQQ: USEPA designated limits for toxic chemicals in
surface waters.  The levels are set to protect plant, fish, and animal habitats in the areas
surrounding the surface waters.

Applicable or Relevant and Appropriate Requirements (ARARs):  Any state or federal law or
regulation that pertains to the protection of human health and the environment in addressing
certain site conditions or using a particular cleanup technology at a site. The Army must consider
whether a remedial alternative meets ARARs as part of the process for selecting a cleanup
alternative for a site.

Background Concentrations: Naturally occurring chemicals present in air, water, or soil in
concentrations which would normally be expected.

Base/Neutral Acid Extractable Compounds (BNAs): Chemicals  detected using a laboratory
procedure designed to determine the concentration of semi-volatile organic compounds.

Baseline Risk Assessment (BRA):  The process whereby risks to human health and me
environment are quantitatively evaluated.  This information is used to determine whether remedial
actions are necessary. The BRA is conducted during the Remedial Investigation/Feasibility Study.

Berm:  An earthen, concrete, or other man-made barrier used to keep liquids from flowing into
or out of an enclosure.

Bioaccunnuation: The build-uj, of toxic  chemicals in living things.

Cancer Slope Factor (CSF):  A number  used to estimate the probability of potential carcinogenic
effects.

Carcinogenic:  Term used to describe chemicals or substances that are known or suspected to
cause cancer in humans based on observed health effects in humans or existing data from animal
laboratory tests.
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                                                     Crab Orchard National Wildlife Refuge EMMA OU ROD
Characteristically Hazardous Waste:  A waste material that exhibits certain potentially hazardous
characteristics such as flammability, toxicity, corrosivity, and reactivity or contains levels of
certain chemicals, as designated by federal regulations.

Clay Rich Soil:  Description of native  soils in this area.

Constituents of Concern or Contaminants of Concern:  Site-related chemicals that pose critical
health concerns to human or environmental receptors because of their toxicity and potential for
exposure.  Although many chemicals at a site may pose a potential risk to human health and the
environment, constituents of concern represent those chemicals mat contribute the majority of
potential risk. At the EMMA OU, the constituents of concern were identified as lead and
nitroaromatic compounds.

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA): A
federal law enacted in  1980 and subsequently modified by the Superfund Amendments and
Reauthorization Act of 1986 (SARA).  This act resulted in the creation of a trust fund, commonly
known as "Superfund," which provides money to investigate and clean up abandoned  or
uncontrolled hazardous waste sites.

Critical Toxicity Values (CTVs): A term used to describe the level of toxicity to ecological
receptors in terms of acceptable daily intake.

Detection Limits: The lowest concentration of a chemical that laboratory instruments or methods
can detect.

Dose-Response: The concept in that the physiological  affect (the response) is directly related to
the level of chemical intake (the dose)  by a living thing.

Ecological Risk Index (ERI): A calculated value used to quantify potential risks to plants and
animals due to the presence of constituents of concern.  The index value is calculated by dividing
the estimated chemical exposure concentrations with the critical toxicity values (CTV).  An ERI
greater than 1.0 is considered to  represent an potential  unacceptable risk.

Exposure Pathways:  The routes by which chemicals reach receptors. These routes may include
(for example) drinking groundwater or inhaling windblown dust.

Feasibility Study (FS):  A study that selects a remedial action at a site, through a series of
evaluation steps.  The FS identifies, develops, and evaluates several alternatives for addressing
contamination.
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                                                    OB* Orchard National WildJfc Rtfige EMMA OV ROD
Ferrous: Containing iron.

Groundwater:  Water that is present in the open spaces between soil particles (silt, sand, gravel)
and/or rock fractures below the ground surface.

Hazard Index (HI):  An indicator of the potential for a hazardous substance to cause
noncancerous health effects in humans. The HI is calculated by dividing estimated human
exposure concentrations by exposure levels that USEPA has determined to be acceptable.  Any
result of mis calculation that is greater than 1.0 is considered to represent a potential unacceptable
risk.

Hydrogeology: The study of groundwater and aquifers.

Indicator Species:  Those species from me list of potential ecological receptors that appear to be
at greatest risk from exposure to potential constituents of concern.

Information Repository: A location where documents and data related to a site investigation and
response actions are maintained to allow the public access to mis material.

Land Use Controls: Management of a property in a manner that minimizes the potential exposure
of hazardous substances to the public.  For example, placing restrictions on the use of
groundwater at a site.

Lowest-Obsenred-ErTect Level (LOEL): The lowest concentration of a constituent of concern at
which an adverse effect is observable.

Magnetometer: An instrument used to detect metal objects.

Manifest: A document mat records the content, chemical characteristics,  amount, generator,
transporter and recipient for every shipment of hazardous waste.  A manifest is required to
accompany every shipment of hazardous waste according to hazardous waste regulations.

Milligram? per Kilogram (rag/kg): A unit of measure used to show concentrations of chemicals
in dry materials such as soil, sediment, or sludge.  This unit (mg/kg)  is equal to parts per million.
As a conceptual example, 1  mg/kg is equivalent to one dollar in a stack of one million dollars.

Milligrams per Liter (mg/L):  A unit of measure used to show concentrations of chemicals in
liquid mafrria's such as groundwater and surface water.
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                                                   Crab Orchard National Wildtfc Refuge EMMA O V HOD
Mobility, Toxkaty, or Volume (MTV): Three indicators of chemical presence and movement in
the environment.  These indicators are used to assess the current and future concentrations of
chemicals in the environment and determine how harmful these chemicals may be to human health
and the environment.

Monitoring Well: A well installed for the purpose of collecting samples of groundwater to be
analyzed for chemicals.  A monitoring well is a permanent structure mat can be sampled
repeatedly over an extended period to track chemical concentrations.

National Oil and Hazardous Substances Pollution Contingency Plan (NCP):  A federal
regulation that outlines the procedures mat must be  followed under the Superfund Program.  The
NCP was most recently revised in 1990.

National Priorities List (NPL):  USEPA's list of the most serious uncontrolled or abandoned
hazardous waste sites identified for possible long-term remedial response actions.

National Emission Standards for Hazardous Air  Pollutants (NESHAPs): NESHAPs are
USEPA air regulations that set minimum operating  standards for certain activities which generate
air pollution.

Nitroaromatic Compounds: Common components of explosives.

Non-carcinogenic:  The term used to describe chemicals or substances that are not known or
suspected to cause cancer in humans. This term generally refers to chemicals that may not cause
cancer,  but potentially produce other unwanted health effects.

No-Observed-Effect Level (NOEL;: The concentration of a constituent of concern mat results in
no observable effect on an ecological system.

Operable Unit:  An individual action that is part of die overall remedy for a particular site.  This
portion of the remedial response manages migration, or eliminates or addresses a release, threat
of a release, or an exposure pathway.  Operable units may address geographic portions of a site,
specific-site problems, or initial phases of an action.

Ordnance: Military weapons and equipment, including artillery and ammunition.

Organic Constituents: Chemical compounds composed primarily of carbon, including materials
such as solvents, oils, and pesticides.
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                                                    Crab Orchard National WiUqfe Refuge EMMA OV ROD
Polychlorinated Biphenyls (PCBs): A group of organic compounds related by their basic
chemical structure.  They are highly resistant to degradation, but have a tendency to be retained
in body tissue.   Due to their efficient electrical conductivity properties, they were widely used in
capacitors, transformers, and other products in the U.S. before 1980.

Practical Quantitation Limit (PQL): A value equal to 10 times the detection limit that reflects
the value above which a chemical can be quantified with acceptable confidence.

Preferred Alternative:  The remedial alternative initially proposed for implementation as a result
of the screening process conducted during the FS.

Present Worth Cost: An economic term used to describe today's cost for a Superfund cleanup
and reflect the discounted value of future costs.  A present value cost estimate includes
construction and future operation and maintenance costs.

Receptor  A human, animal, or plant that could potentially receive exposure to chemicals
migrating from or present at hazardous waste sites.

Record of Decision (ROD):  A legal document that describes in detail die remedy selected for an
entire NPL site or a particular operable unit.  The ROD summarizes the results of the RI/FS and
includes a formal response to comments supplied by the public.

Reference Dose (RfD): The daily acceptable level of constituents of concern intake.  This
number is used to estimate potential for non-carcinogenic effects.

Remediation Goals:  Remedial action objectives and remediation goals are the target cleanup
levels for chemicals at a contaminated site.

Remedial Investigation (RI): A study that supports the selection of a remedial action at a
Superfund site.  The RI identifies the nature, magnitude aid extent of contamination associated
with a Superfund site.

Resource Conservation and Recovery Act of 1976 (RCRA): The federal law that establishes a
regulatory system that governs procedures to be used in generating, storing, transporting, treating,
and disposing of hazardous waste.

Responsiveness Summary: Comments presented during the public meeting and received during
the public comment period that are considered and addressed by the lead agency.  The Crab
Orchard Responsiveness Summary is Appendix B of this ROD
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                                                   Crab Orchard National WUtOtfe Refitge EMMA OU ROD
Risk Assessment Guidance for Superfund (RAGS): A document produced by the USEPA as a
guide for conducting risk assessments under Superfund.

Sediment:  Soil and other material mat settles to the bottom of a stream, creek, or lake.

Semi-Volatile Organic Compounds (semi-VOCs): Semi-VOCs are organic chemicals that
vaporize less readily than VOCs.  These compounds include many polynuclear aromatic
hydrocarbons and pesticides.

Superfund Amendments and Reauthorizauoa Act of 1986 (SARA): This act modified specific
provisions in CERCLA.

Surface Water:  Water on me earth's surface such as streams, ponds, and lakes.

To Be Considered (TBQ Values - State advisories, guidance, non-binding guidelines, or other
standards mat are not legally binding that may be considered when fashioning a protective remedy
for a site.

Toxkity Characteristic Learning Procedure (TCLF):  USEPA-approved laboratory procedure
used to determine if a waste material is characteristically hazardous.

Toricity Value:  Used to indicate the level of toxicity of the constituents of concern at the site.

Uncertainty Factor:  A measure of the uncertainty inherent in assumptions  made in risk
assessments.

Unexptoded Ordnance: An explosive device mat has not been detonated.

Volatile Organic Compounds (VOCs):  Organic liquids that readily evaporate under atmospheric
conditions and exhibit varying degrees of solubility in water.  Examples of VOCs include benzene
and xylenes.
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                                                    Crab Orchard National Wildlife Refuge EMMA OU ROD
                                      Appendix A





                              Responsiveness Summary
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                                                  Graft Orchard National WOdlfr Refuge EMMA OU ROD
        Summary of Comments Received During the Crab Orchard
           EMMA OU Public Meeting Held on October 19,1995

A number of oral comments were received from members of the community during the public
meeting for the Crab Orchard NWR EMMA OU, held on October 19, 1995. Public comments .
were solicited on the Proposed Remedial Action Plan. These comments were transcribed by Ms.
Valerie Bleyer, a court recorder and Notary Public.  In many cases comments were repeated by
the commentor, or by other cotnmentors throughout the course of the public meeting. In these
cases, the comments have been consolidated.  In most cases, the comments have been paraphrased
for clarity.

A summary of the written responses received at the public meeting and letters received by the
public follows the oral comments.

Comment 1      When, on what date, was the was the decision made to change from
                 Alternative 4 to Alternative 3A?

Response:        The USAGE Devaluated Alternative 3A on October 13, 1995 and decided to
                 present Alternative 3A as the preferred alternative.

Comment 2      Can the public comment period be extended in light of the fact that the
                 proposed remedy has changed? (several commentors, oral and written)

Response:        The public comment period was extended by 30 days. The public comment
                 period ended on November 29, 1995.

Comment 3      Under Alternatives 3A, 3B, and 3C will  affected soils be incinerated? If so,
                 where? Do all of the Alternatives include incineration except for
                 Alternative 1?

Response:        Soils containing nitroaromatic compounds in excess of 100,000 mg/kg will be
                 incinerated. It is intended that these soil will be transported to an existing
                 commercially available licensed incinerator that is not located on the refuge.
                 The specific incinerator will be identified during the design phase of the
                . remedial action.  The removal contractor will select the incinerator subject to
                 approval by the USACE. Each of the remedial alternatives evaluated (except
                 Alternatives 1 and 6) include oftsite incineration of the soils at Sites COC-3
                 and COP-4 that contain levels of nitroaromatic compounds in excess of
                 100.000 mg/kg.  Although Alternative 6 includes on-site incineration.
                 Alternative 6 is not die selected remedial alternative.
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Comment 4      I have a problem with the proposed remedial action plan that was sent out with
                  Alternative 4 as the selected remedy.  Alternative 4 is based on the assumption
                  that a special waste landfill will accept the affected soil for disposal.  If a
                  landfill will not accept the waste, will it then be incinerated on site?  Does
                  offsite incineration depend on whether a landfill will accept the resulting ash?
                  What will happen if no one will accept the soil?

Response:        There are a number of special waste landfills in the immediate area (including
                  one in Jackson County) that could accept the affected soils. The Army does
                  not anticipate any problem with acceptance of the waste by a special waste
                  landfill.  Under Alternatives 1 through 5 and Alternative 7, the soils will not
                  be incinerated on-she for any reason.  The offsite incineration of soils with
                  levels of nitroaromatic compounds in excess of 100,000 mg/kg is not
                  dependent on the disposition of the resulting ash.  In the unlikely event mat no
                  offsite facility will accept die soils, the Department of the Army will examine
                  the options available and inform the public of its preferred option.  A change
                  in the remedy will require a ROD Amendment and further public comment

Comment 5      Will Alternative 6 (on-site incineration) be considered?

Response:        Each of the remedial alternatives were considered in the remedial alternative
                  selection process, based on the nine criteria specified in CERCLA and NCP,
                  and identified in Section 9.0 of the ROD. After careful evaluation of each
                  alternative, Alternative 3 A has been selected as the preferred alternative.
                  However, selection of the final  remedy will take into account input received
                  from the public.

Comment 6      There are other safer ways than incineration to clean up affected soils.
                   According to a specific article referenced, the most dangerous chemicals on  the
                   planet can be neutralized with common sewage sludge and water.  The U.S.
                   Army Aberdeen Proving Grounds in Maryland released their initial findings on
                   neutralization of lethal mustard agents showing mat exposing the agent to hot
                   water and men sewage changed the agent to a nonhazardous waste.  The most
                   dangerous chemicals manufactured by humans can be neutralized very safely
                   without incineration.
                   The article referenced addresses neutralization of mustard gas agents. Mustard
                   gas agents are made of very different types of chemicals than nitroaromatic
                   compounds.  Therefore,  the neutralization method discussed in die article
                   would not be effective on nitroaromatic compounds. Studies on neutralization
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                                                    Crab Orchard national Wildlife Refuge EMMA OU ROD
                 techniques for nitroaromatic compounds have been conducted. However, most
                 of these techniques use solvents and would generate another potentially
                 hazardous waste stream.

Comment 7      One oommentor was concerned that the affected soil will be incinerated on-site
                 and that other material from around the world will be brought here and burned.

Response:        On-site incineration is not included in the selected remedial Alternative 3A. At
                 no time was incineration of material from other sites considered.

Comment 8      Why, out of seven alternatives, are six of the-i incineration?  Why haven't
                 other technologies been considered here?

Response:        Other remedial technologies were considered.  For example, composting
                 (Alternative 5) is a viable technology that was considered.  However, due to
                 the fact that the remediation goals are below detection levels, capping or
                 covering of treated (composted soils) had to be added to increase the
                 effectiveness of the composting alternative. Incineration is a safe and viable
                 treatment method for nitroaromatic compounds. Only those soils mat pose a
                 potential explosive hazard are proposed for offsite incineration.

Comment 9     What is more important, people's health or money?  Why is it that money
                 always takes precedence over health?

Response:       Selection of a remedial alternative is based on an evaluation of nine criteria
               .  specified in CERCLA and the NCP. Protection of human health and the
                 environment and cost are two of the nine evaluation criteria.  Cost is a
                 consideration in instances where remedial alternatives provide equal protection
                 for human health and the environment. This is the case for many of the
                 alternatives evaluated for the EMMA OU.

Comment 10     Where will die excavated soil be  taken for incineration? Is it a private
                  incinerator or a government facility?

Response:        Soils containing nitroaromatic compounds in excess of 100,000 mg/kg  will be
                  incinerated.  It is intended  in die  proposed alternative that these soil will be
                  transported to a commercially available licensed incinerator mat is not  located
                  on the refuge.  The  specific incinerator will be identified during the design
                  phase of the remedial action.  The removal contractor will select the incinerator
                  subject to approval by the USACE.
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Comment 11     One of my big concerns is the emission of dioxins when incineration takes
                 place.

Response:        Dioxin is not a by-product of nitroaromatic compound incineration. In order
                 for dioxin to be produced chlorine must be present.  Chlorine is not a
                 component of nitroaromatic compounds.

Comment 12     Are Sites COC-3 and CQP-4 in the public area or are they closed off already?

Response:        Sites COC-3 and COP-4 are closed off to the public.

Comment 13     One commentor requested that information be mailed to the public concerning
                 the change in the preferred alternative from Alternative 4 to Alternative 3A.

Response:        Information regarding the change in the preferred alternative from
                 Alternative 4 to Alternative 3A is included in the ROD which is located in the
                 administrative record as well as each of the information repositories.  Because
                 the ROD is readily available to the public through the information repositories.
                 this information has not been mailed directly to the public.

Comment 14     One commentor preferred that Alternative 3C be selected as opposed to
                 Alternative 3A, because Alternative 3C appears to be more protective due to
                 the greater number of protective layers over the remaining soil.
                  Both of these alternatives equally prevent direct contact with soils containing
                  nitroaromatics and lead above remediation goals and therefore are equally
                  protective of human health and the environment.
 Comment 15     When was die last explosive or toxic material deposited on these sites?  Has
                  any refuge person become sick in the last fifty years? Why is necessary to get
                  rid of the affected soils now?

 Response:        The latest that this type of material would have been deposited on the sites is
                  when the Illinois Ordnance Plant was closed in 1945. There is no record that
                  Crab Orchard NWR employees have ever become ill as a direct result of
                  exposure to constituents at die EMMA OU sites.  Based on die results of the
                  BRA, soils at Sites COC-3  and COP-4 pose a potential unacceptable risk to
                  human health and the environment.  CERCLA requires die potentially
                  unacceptable risks to be mitigated.
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                                                     Crab Orcruird National WiUOye Refiige EMMA OU ROD
Comment 16     Are the constituents of concern leaching into the groundwater at increasing
                 rates? Is it possible that constituents of concern will leach into the lake?

Response:        Several of the EMMA OU wells have been affected by constituents of concern.
                 However, it would take a very long time for the constituents of concern to
                 migrate to the Crab Orchard Lake, due to the types of soils present.  It is also
                 likely mat the constituents would be naturally degraded before it could reach
                 Crab Orchard Lake.  Based on the data collected during the RI conducted at
                 the EMMA OU, there is no evidence that concentrations are increasing in
                 monitoring wells, or that constituents of concern are migrating toward Crab
                 Orchard Lake.  Groundwater monitoring will provide warning of constituent
                 migration.

Comment 17     Has the USEPA or the Army Corps of Engineers looked at the risk involved in
                 transporting affected soil off site?

Response:       The risk of transporting affected soils offsite were addressed in the Feasibility
                 Study and the Proposed Plan under the analysis of short-term effectiveness.
                 Precautions will be taken during offsite transportation of affected soils. Trucks
                 leaving the site  will be covered to prevent dust generation and spillage during
                 transport.  The  trucks will also be decontaminated prior to leaving the site to
                 prevent offsite transport of soils on the outside of the trucks. In addition, the
                 trucks will be routed away from residential areas during transport. These
                 precautions will be taken to prevent the possibility of contact with affected
                 Sites COC-3 and COP-4 soils being transported.

Comment 18     If there will be  no on-sfte incineration, why are all of those air monitors being
                  put around the area?  Who reads the air monitors?

Response:       The air monitoring equipment is associated with the remedy for the PCPs
                  Operable Unit,  not the EMMA OU remedy.  The commentor should obtain
                  further information concerning the air monitoring activities at the PCB OU
                  from the PCB OU  information repository.

Comment 19     Are the sites here on the refuge unique nationally except for the fact mat they
                  are on  a National Wildlife Refuge?  Is the remedy being proposed unique or
                  different than what is being used on other sites?

Response:        Sites with nitroaromatic compounds in soil are not unique. There are many
                  locations throughout the nation  where  munitions were historically manufactured
 «mborch-«6/«>d-«/O4/19/96
A-5
Environmental Sdatet A Engineer**, tie.
-------
                                                   Cfab Ordiant Nalanal WUd&e Kefitge EtOtA OU ROD
                 resulting in nitroaromatic compounds and metals impacting the environment
                 A few of these sites are also located on state or national wildlife refuges.  The
                 remedy being proposed for the EMMA OU is generally more conservative than
                 remedies that have been proposed at other sites.

Comment 20     Would the proposed actions for the EMMA OU be setting the standard for
                 cleanup levels state-wide for this type of contamination?

Response:        Geanup standards are determined on a site-by-site basis under CERCLA.
                 Therefore, the clean-up levels set for the Crab Orchard National Wildlife
                 Refuge EMMA OU are not necessarily applicable to other sites within die
                 refuge or at other sites in Illinois.

Comment 21     Why did the US Army Corps change its mind from Alternative 4 to 3A?  Was
                 ft based on a dollar figure?

Response:        Alternative 3A and Alternative 4 are equally protective of human health and
                 the environment. Therefore, die additional costs associated with Alternative 4
                 were not justifiable, within the constraints of federal appropriation law.  Since
                 both alternatives achieved protectiveness objectives, the least costly alternative
                 was selected.

Comment 22     Was the big factor for the change from Alternative 4 to 3A the level of
                 protection?

Response:       No, as stated in response'to Comment 22, the level of protection of human
                 health and die environment are essentially equal.

Comment 23     To die best of USEPA's knowledge are there or nave there been any sites in
                 the United States similar to this Operable Unit mat do not include incineration?

Response:       Yes, there are other sites in die United States similar to the EMMA OU that do
                 not include incineration.

Comment 24    Were the other alternatives, such as composting, screened out based on cost?

Response:       As mentioned in response to Comment 9, cost is one of several factors
                 evaluated in the remedial action selection process.
 cnbof
-------
                                                    Crab Orchard National midHfe Refitge EMMA 0V ROD
Comment 25     Will there be any detonation of explosives on-site?  What is die difference in
                 emissions of detonation compared to just striking a match and burning the
                 affected soils?  Are the emissions substantially different between detonation and
                 incineration?

Response:        It is possible that unexploded ordnance may be exploded on-site if it is deemed
                 that transporting the material offsite would pose an unacceptable hazard.  The
                 air  emissions resulting from open detonation would not be captured  and
                 treated, whereas the air emissions from incineration of nhroaromatic
                 compounds would be captured, monitored, and treated prior to release into the
                 environment

Comment 26     It was stated earlier that there are monitoring wells directly under the site.
                 When were the wells put in place and how long have you been collecting data?
                 Have you been collecting data since 1991? How long did it take for the TNT
                 to show up in the wells?

Response:        A total of 28 monitor wells were installed at the EMMA OU sites between
                 1988 and 1993. Data were collected during Phases I and n of the RI in 1991
                 and 1993.  Levels of TNT were detected in some of the wells during the 1991
                 sampling event.

Comment 27    The USFWS read a statement expressing concern about USACE's selection of
                 Alternative 3A as the selected remedy.

Response:       Discussions between USFWS, USAGE, USEPA, and EPA have resulted in an
                 agreed-upon approach to implement Alternative 3A.  The remedy accepted by
                 the agencies modifies the implementation of Alternative 3A at Site COP-4.
                 This agreed-upon change has been incorporated into this ROD.
 crmborctn6/njd-«A>4/l9/96
A-7
                                                                                      f.fac.
-------
                                                  Crab OrtHard National Wildlife Refuge EMMA OU ROD
           Written Comments Received During the Crab Orchard
           EMMA OU Public Meeting Held on October 19,1995,
                   and During the Public Comment Period

Comment 1     Place the U.S. Fish and Wildlife Documents in the repository.

Response:       It is unclear which documents the commentor is referring to.  Those documents
                utilized for the decision presented in the ROD have been placed in the
                appropriate repositories.

Comment 2     I would like to see a remedial action alternative that does not include
                incineration. The health of the people should always come first.  Storing the
                contaminated soil in large drums or barrels until we know how to safely
                detoxify should be an option.

Response:       The soils containing levels of nitroaromatic compound above 100,000 mg/kg
                pose a threat of explosion. Therefore, handling these soils or storing these
                soils in drums or containers without any treatment would create a more
                dangerous situation. Incineration is a safe and viable treatment method for
                nitroaromatic compounds. Only those soils that pose a potential explosive
                hazard are proposed for offsite incineration.
Letter to Mr. Joe Laird from Ms. Rose Rowdl
"If it be that USEPA and the responsible parties have made the wrong decision Southern Illinois
will lose one of its greatest assets hunting and fishing at Crab Orchard a hunting ground that
attracts people from all over the country."

Response:        The Army believes that the implementation of Alternative 3A will protect the
                 valuable assets of the Crab Orchard National Wildlife Refuge by removing soil
                 with the highest concentrations of nitroaromatic compounds and destroying
                 them in a commercial incinerator.  With this removal, the wildlife at the
                 Refuge will not come into contact with dangerous levels of nitroaromatic
                 compounds and hunting and fishing can safely continue.
 cnbo(ch-f6/rod-«/04/l9/96
A-8
                                                           Environmental Science 4 Engineering. Inc.
-------
                                                     Crab Orchard NoOonai ^TOdSfe Refuge EMMA OU ROD
Letter to Mr. Nanjunda Gowda from Ms. Rose Rowell dated November 19,1995
"....if adioxin producing incinerator is sited at the Refuge, there is an imminent endangerment
that deer contaminated with dioxin will be put on the family table.  Scientists tell us that the body
of the average American already has a dangerous level of dioxin, due to atmospheric fallout and
dioxin contaminated food and the least bit of exposure could cause devastating, irreversible health
problems.  Surely, this includes the  wildlife — as scientific researchers tell us that dioxin has a
devastating effect on wildlife not only contaminating the game. It has the capability to cause birth
defects, mutations, the inability to reproduce, etc	we would lose me $50 million dollars that
the hunters bring into mis area each year	the right thing, the responsible thing to do is to
stop the incinerator, it cap be stopped	the imminent overall consequences are going to be
too great, as the Crab-Orchard Refuge is a unique site, where food  is being raised for the hunters
table."

Response;       This comment appears to be directed to the remedy proposed for
                 implementation at the PCB OU. On-site incineration.is hot being considered  .
                 for implementation at die EMMA OU.
Letter to Mr. Kevin Quinn from Ms. Rose Rowell dated November 20,1995
"I am writing hi regard to the munitions site superfund cleanup slated for the Crab Orchard
National Wildlife Refuge, Marion, Illinois.

As we understand me remediation plan calls for the contaminated soil to be taken offsite to a
commercial incinerator for disposal.

We are concerned because when die public was originally notified of die Munitions meeting, die
preferred memod was Alternative 14 by the time we got to the meeting, the Corps had revised the
method to be used to Alternative f3A.

If mere is a thought of changing again to another alternative - Alternative 16, we want it on
record mat diere is great opposition to an incinerator being brought into die Crab Orchard
Wildlife Refuge and with just cause."

Response:        Alternative 3A is die selected remedy.
cnboRh-rf/rad-«/04/19/96                         A-9               Emimmitnml Sdatef A Eitgattemg. Me.
-------
                                                    Crab Orchard Notional Wttfljfr Refuge EMMA OU ROD
                                        Appendix B





                              Administrative Record Index
cnborch-<6/rod-
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                   ADMINISTRATIVE RECORD INDEX
     EXPLOSIVES/MUNITIONS MANUFACTURING AREA OPERABLE UNIT
             CRAB ORCHARD NATIONAL WILDLIFE REFUGE
                         MARION, ILLINOIS
Doc
No.
1
2
3
4
5
6
7
8
9
10.
11
12
13
Date
04/11/88
08/00/88
11/15/90
01/04/91
03/08/91
07/26791
07/30/91
08/01/91
08/91
08/16/91
08/19/91
through
10/02/91
12/24/91
01/00/92
Author
Woodwwd-Clyda
Contulttutt

O'BriM&Oera
EnfiaMn.be.
UXB Int. lac.; ESB
USEPA
ESE
ESE
ESE
DOUDA
DOI;DA

UXB
ESE
ESE
Recipient)
USACE-OmalM
USFWS.USDapiaf
Inc.'
USAC&4»Baaa
Japa. USAC&OoMte;
Tad.QAS
USAC&Oaa*a
USACe-OBMB*
JMR USACE-QiMai*
FwnU. USACE-LMRD;
Daea, USACE-St. LOOM;
OhuMa.USACB.
MRD-. Paro. USAGE-
Huatcvai*; Moo*.
DOI/FWS; Lopa.
USEPA; Davis. IEPA;
luatimrlo. UXB
KM; DA; USEPA;
te"\
DOt: DA; USEPA: -
IEPA
USEPA togmV;
IEPA; DOI. DA
Japp. USACE-OoMbt
USAC&Omte
USAC&OnHta
TaWDMeriptiM
Conflnnttiao Study at IB* Cnb
Oehwd NtttoMi WUdlife lUfcf*
Pint DERA Sto (S volinnM)
ReaMdkllnvMtifHiMlUpon
Cn* Orefaitf fWoMl WMifc
IMht*(3VolaMi)
Cnb OnM NWooM WBdllfc
lUftf^. Marian IL.
HMkk M* Sditjr W«k Pte
Lt^ttft fK IKDnHllOB tB 09
inetottidhltoQAPF

POM* I AatMtiM. tawr OlMMto
Iteinri WMn% ftrflw^ MMiam. 0,

PtaM 1 AetMriM. EMMA OU.
Mttion. IL
EMMA OU CbMMl DM*
AcqaWtiaa RM, OR* OchHtf
WiUlifelUhK*. MHIOB, O. (2
VollOBM)
M«wnma4Mi of ApMHHnt fat Oak
OrchwiNWR
AMndaMKN*. 1 Cola*
M«Mran*Mof AfTMaMatfor Ctak
OrcaanlNWR
F«daMl Faaaay Affiiaia Uad«

Duly Qoaliqr Coatrat Rapora
EMMA OU AMdytical Dam Rapan.
Cna OrekMtf WMife Rafc«^
Mchoa.O.
(2 votiaaw)
SoU Boriat Lof^ MoaitarWril
Lop, and Moater Wall CoeancaJoa
Digram*. TV* Ciah Orckird EMMA
OU PhaMllava«iaatiaa,Marioa,IL
tag.
1287
1722
72
37
107
106
430
20
6
95
«4
996
99
enbordi-i6/fod-*/04/19/96
                               P«j« I of 5
uii. /•
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                    ADMINISTRATIVE RECORD INDEX
      EXPLOSIVES/MUNITIONS MANUFACTURING AREA OPERABLE UNIT
              CRAB ORCHARD NATIONAL WILDLIFE REFUGE
                           MARION, ILLINOIS
Doc
No.
14
15
16
17
18
19
20
21
22
Date
01/10/92
01/17/92
02/21/92
03/26/92
03/30/92
05/18/92
OS/27/93
09/10/93
11/01/93
Author
Bornboft, USAGE- •
Omaha
ESE
ESE
Taggart, USAGE-
MRD Laboratory
McKinley. ESE
McKinley. ESE
McKinley. ESE
McKinley, ESE
McKinley. ESE
Recf>ientt»
USEPA Region 5; IEPA;
FWS; Liu. Japp, Bauer.
USACE-Omaha
Japp. USACE-Omaha;
Ohnttead. USAGE-
MRD; Famll. USACE-
LMRD; Dae*. USACE-
St. Louis; Carter, (EPA;
Logan. USEPA;
Moore. FWS
Richer. USACE-Omaha;
Ohostead. MRD;
Nebelsick, USAGE
Japp. USAC&Omaha
Richer. USACE-Omaha;
Farrell. USACE-LMRD;
Dace. USACE-SL Louis;
Ohnstead. USACE-
MRD; Logaa. USEPA;
Moore. DOI/FWS;
Cuter. IEPA;
Lombudo, UXB
Fischer. USACE-Omaha;
Novak, USEPA; Moore.
DOI; Carter. IEPA
Fucher. USACE-Ooaha;
O «ead, USAGE-
K* J>; Due. USACE-St.
Louis; Faneil. USACE-
LMRD; Moore.
DOI/FWS; Gowda,
USEPA; Nuaabauai.
IEPA; LxMBbudo, UXB
Fischer. USAC&Omaha;
Nuscbaum. IEPA;
Gowda. USEPA; Moore.
DOI
Gowda. USEPA Region
5; Fischer. USAGE-
Omaha; Schupp.
USEPA; Nuaabtum.
IEPA; Sattelberg. FWS
Tide/Descriptioa
Letter, re: Expiration of Comment
Period for the FFA
EMMA OU Quality Control
Summary Report. Crab Orchard
Wildlife Refuge. Marion. IL
Letter, re: Replacement page* for
the Analytical Report
Quality Assurance Laboratory Results

Orchard EMMA OU Phase I
Remedial Investigation. Marion, IL
Letter, re: Crab Orchard EMMA OU
(replacement pages for the Analytical
Data Report)
EMMA OU Phase O Investigation
Amended Chemical Data Acquisition
Plan, Crab Orchard NWR. Marion.
IL (2 Volumes)
Final EMMA OU Phase II
Investigation rVeluninary Risk
NWR, Marion. IL
Letter, re: Crab Orchard NWR
EMMA OU, SOPs for Work
Performed on 1 0/1 1/93. Pursuant to
the Preliminary Risk Assessment
(with atsachmenti)
Page
2
165
39
287
340
46
317
289
54
cnboich-i6/Rxi-«AM/19/96
                                 Page 2 of 5
Environmental Science A Engineering. Inc
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                    ADMINISTRATIVE RECORD INDEX
      EXPLOSIVES/MUNITIONS MANUFACTURING AREA OPERABLE UNIT
              CRAB ORCHARD NATIONAL WILDLIFE REFUGE
                           MARION, ILLINOIS
Doc
No.
23
24
25
26
27
28
29
30
31
32
Date
12/02/93
01/21/94
02/11/94
02/18/94
O4/15/94
04-
05/00/94
09/15/94
09/28/94
11/00/94
11/01/94
Author
McKinley. ESE
ESE
ESE
Musgrave. FWS
Butler. City of
Marion, Illinois
Technically, Issue
No. 27
McKinley, ESE
McKinley. ESE
ESE
Butler. Duly
Egyptian
Recipience)
Gowda. USEPA Region
5; Richer, USACE-
Omaha; Schupp,
USEPA; Nussbaum,
EPA; Shaw, IEPA;
Ssttetberg. FWS
USACE-Onaha
USACE-Omaha
Gowda, Deamor. USEPA
Region 5; Fischer.
White. USACE-Omaha;
Project Manage.
Ntckey-Tebrogge, IEPA;
Lombaxdo, Schlumberger
Eifirffniimml $••»•«••
Mufgrmve. FWS;
Congressman Poihard;
Dwuner. USEPA;
Nickey-Tebrugge, IEPA;
White. USACE-Omaha
Public
Richer. USACE-Omaha;
Cotner. USACE-St.
Louis; Novotny.
USACE-MRD; Farreil.
US/ CE-LMRO; Gowda.
USEPA; Nuohaum.
IEPA; Sattelberg. FWS;
Robert!. WWES
Racher. USACE-Omaha;
Cotner. USACE-St.
Louu; Novotny,
USACE-MRD; Famll.
USACE-LMRD; Gowda.
USEPA: NuMbaiim.
IEPA; Sanelberg. FWS
Public
Public
Title/Description
Letter, re: Further Information
Regarding SOP* Submitted on
1 1 AH/93 (this infonnatioa to be
considered addendum to Phase II
CDAP)
EMMA OU Crab Orchard NWR,
Marion. IL. Phase 0 Analytical Data
Report (2 Volumes)
EMMA OU Quality Control
Summary Report, Gab Orchard
NWR. Marion, IL. Phase O RI/FS
Draft General Fact Sheet Outlining
Status of Suporfund Activities at the
Crab Orchard NWR
Letter, re: Cleanup at the Crab
Orchard National Wildlife Refuge
Article, re: Environmental and
Ecological Study at the National
Wildlife Refuge
Draft Final Remedial Investigation/
EMMA OU. Crab Orchard NWR,
Marion. IL (5 Volumes)
Addendum to the Draft Final
Remedial lnvtftig«tiflii/P*"1 "*" PJrit
Assessment Report. EMMA OU.
Crab Orchard NWR. Marion. IL
Fact Sheet: Crab Orchard National
Wildlife Refuge. EMMA OU
Newspaper Article, re: Public
Meeting for the Crab Orchard NWR
Page
10
565
91
15
2
I
2118
77
6
2
craborch-t6/rod-«/04/19/96
                                 Page 3 of 5
Environmental Science A Engineering, Inc.
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                    ADMINISTRATIVE RECORD INDEX
     EXPLOSIVES/MUNITIONS MANUFACTURING AREA OPERABLE UNIT
              CRAB ORCHARD NATIONAL WILDLIFE REFUGE
                           MARION, ILLINOIS
Doe
No.
33
34
35
36
37
38
39
40
4i
42
43
Date
11/01/94
11/02/94
11/02/94
11/18/94
09/29/95
09/29/95
02/14/95
09/15/95
09/26/95
10/24/95
11/01/95
11/02/95
11/03/95
11/06795
Author

Mariano, Southern
Dlinoisan
Grime*. Marion
Daily Republican
Monett.FWS
USAGE
ESE/USACE
USAGE (ESE)
USAGE (ESE)
USAGE (ESE)
USAGE (Southern
Reporting)
USAGE (ESE)
Recipients)
Public
Public
Public .
Fischer. USACE-Omshe;
While. USAGE; Gowda,
Deamer. USEPA;
NucibauiBt Ntckey*
Tebrugge. IEPA;
McKinley.Fiebcr.ESE;
Boyd, WCC; Miller.
FWS; Berry. CONWR
USACE-Laird.
Administrative Record
Public
USAGE. USFWS. [EPA.
USEPA
Public
USAGE. USFWS. IEPA.
USEPA
USAGE. USFWS.
USEPA. IEPA. ESE
Public
Title/Description
Photos, re: AvaOabDity Seerion and
Public Meeting
Newspaper Article, re: Cleanup at
the Crab Orchard NWR
Newspaper Article*, re: Cleanup Plan
for the Crab Orchard NWR
Letter, m Quottiofit tuid *-flfniiwrti
Made During the EMMA Public
Meeting. November 1. 1994
Technical Memorandum of the
Itemizatioa of Changes and
Assumptions between the FS Costs
and the Proposed Plan Costs
Proposed Plan/Fact Sheet: Crab
Orchard National Wildlife Refuge.
EMMAOU
Draft Final Addendum to the Draft
Final Remedial Investigation/Baseliae
Explouvet/Munaioas Manufacturing
Areas Operable Unit. Crab Orchard
National Wildlife Refuge. Marion.
Illinois
Public Notice for Public Meeting of
October 19. 1995 on Proposed Plan
EMMAOU
Final Revised Feasibility Study
Report, Explosives/Munitions
Manufacturing Areas Operable Unit.
Crab Orchard National Wildlife
Refuge. Marion. Illinois
Transcripts of Proposed Rcmedttl
Action Plan Public Meeting of
October 19. 1995
Public Notice for Encoded Public
Remedial Action Plan
Page
4
3
2
3
63
16
82
1
450
71
1
cr»borch-*6/rod-«/04/19/96
                                 Page 4 of 5
Environmental Science A Engineering. Inc.
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                             ADMINISTRATIVE RECORD INDEX
               EXPLOSIVES/MUNITIONS MANUFACTURING AREA OPERABLE UNIT
                       CRAB ORCHARD NATIONAL WILDLIFE REFUGE
                                    MARION, ILLINOIS
Doe
No.
44
45
46
47
Date
02/87
12/78
TBD
TOD
Author
United State* Army
Toxic and Hazardous
Material* Agency
(Arthur D. Little.
Inc.)
USFWS (Booker
Associates. Inc.)

USAGE
USAGE (ESE)
Recipients)
USAGE, Administrative
Record
AdroiniU lative Record
Administrative Record
USAGE. USFWS.
USEPA. IEPA
Tide/Description
Testing to Determine Relationship
Sludge Component! and Reactivity,
Final Report
Ctab Orchard National Wildlife
Refuge Mailer Plan Technical Report
Technical Memorandum. Updated
Coat Data for Remedial Alternativoi
Presented ia ROD
Record of Decision (ROD) for Crab
Orchard National Wadlife Refuge.
Rxf>1«f fVAfSMonftmis Maiiiifccnirmg
Arais (EMMA) OpenMe Unit (OU)
Page
71
169
TBD
TBD
TBD - to be determined.
         crtborch-«6Vrod-»/04/19/96
                                           PageS of S
Environmental Science A Engatttr^tg. bit.
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                     ADMINISTRATIVE RECORD INDEX
     EXPLOSIVES/MUNITIONS MANUFACTURING AREA OPERABLE UNIT
               CRAB ORCHARD NATIONAL WILDLIFE REFUGE
                            MARION, ILLINOIS
                             ACRONYM GUIDE
Acronym
CONWR
DA
DOI
EMMA
ESE
FFA
FWS
ffiPA
LMRD
MOA
MRD
NWR
OU
RI/BRA
SOP
USAGE
USEPA
UXB
         Definition
Crab Orchard National Wildlife Refuge
U.S. Department of Army
U.S. Department of the Interior
Explosives/Munitions Manufacturing Areas
Environmental Science & Engineering, Inc.
Federal Facility Agreement
U.S. Fish and Wildlife Service
Illinois Environmental Protection Agency
Lower Missouri River Division
Memorandum of Agreement
Missouri River Division
National Wildlife Refuge
Operable Unit
Remedial Investigation/Baseline Risk Assessment
standard operating procedure
U.S. Army Corps of Engineers
U.S. Environmental Protection Agency
UXB International, Inc.
   cnbofdi-i6/red-«/04/19/96
                                    Phgo 1 of 1
                                   Environmental Science A. Engineering. Inc.
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                ADMINISTRATIVE RECORD GUIDANCE INDEX
    EXPLOSIVES/MUNITIONS MANUFACTURING AREA OPERABLE UNIT
               CRAB ORCHARD NATIONAL WILDLIFE REFUGE
                               MARION, ILLINOIS
(EPA Guidance Documents are available for review at USEPA Region 5, Chicago, IL)
           Title

Environmental Impact Assessment

Remedial Action of Waste Disposal
 Sites (Revised), EPA/625/6-85/006

Guidance for Conducting Remedial
 Investigations and Feasibility
 Studies Under CERCLA, EPA/540/6-89/004

Remedial Action Costing Procedure
 Manual, EPA/600/8-87-049

CERCLA Compliance with Other Laws
 Manual: Draft Guidance,
 EPA/540/G-89/006

Guidance on Preparing Superfund
 Decision Documents:  the Proposed
 Plan, the Record of Decision,
 Explanation of Significant
 Differences, the Record of
 Decision Amendment (Interim
 Final)

CERCLA Compliance with State
 Requirements,
 Publication 9234.2-05/FS

Risk Assessment Guidance for Superfund:
 Volume I.  Human Health Evaluation
 Manual, Part A, Interim Final, OSWER
 Directive 9285.7-01

Guidance for Conducting
 Remedial Investigations and
 Feasibility Studies Under
 CERCLA (Interim Final)

National Contingency Plan

Role of Baseline Risk Assessment in
 Superfund Remedy Selection Decisions,
 OSWER Directive 9355.0-30
                                               Author

                                             Larry W. Canter

                                             USEPA


                                             USEPA



                                             USEPA


                                             USEPA



                                             USEPA
                                             USEPA
                                             USEPA
                                             USEPA
                                             USEPA

                                             USEPA
              00/00/77

              00/00/85


              00/00/88



              00/00/88


              08/00/88



               10/00/88
              00/00/89
               00/00/89
               07/00/89
               08/08/90

               00/00/91
  cnboreh-i6/rod-«/O4/19/96
                                          1 of 2
Environmental Science A Engineering. Inc.
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Title 35: Environmental Protection
  Subtitle G:  Waste Disposal
  Chapter I:  Pollution Control Board

Compost Compaction Evaluation
  Report No. CEIHA-TS-CR-93043

Windrow Composting Demonstration for
  Explosives—Contaminated Soils at
  the Umatilla Depot Activity,
  Hernuston, Oregon, Report
  No. CETHA-TS-CR-93043

Windrow Composting Engineering/
  Economic Evaluation, Report
  No. CETOA-TS-CR-93050

Olinois Environmental Protection
  Act, 415ILCS. Title I-XV

40 Code of Federal Regulations
  Parts 260-270
State of Illinois



Roy F. Weston. Inc.


Roy F. Weston, Inc.
04/00/92
00/00/93
00/00/93
Roy F. Weston, Inc.
State of Illinois
00/00/93
01/13/93
   crthoreh-i6/rod-«/04/l 9/96
                                                 2 of 2
               Environmental Science A Engineering. Inc.
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                                                 Crab Orchard National VKUttfe Kefitge EMMA OU ROD
                                      Appendix C





                   Letters of Concurrence from Support Agencies
cnbwch-t6/rod-a/04/I9/96                                        Environmental Science A Engineering. Me.
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                              FIELD -Vl.t.. 4i-..«
                                                                   ^002
            United States Department of the Interior
                        OFFICE OP THE SECRETARY
                                  D.C. 2024O
                                          .   JUL 2 6  1995

Mr. Rayaond J. Fata
Acting Deputy-Assistant Secretary of the Aray •
Environment, safety and Occupational Health
Office, Assistant Secretary of the Aray
ATTN: SAXLB-BSOH
110 Aray Pentagon, Rooa 2ES77
Washington. D-C. 23ioi-oiio
                             .   *•
Kr. Valdas V. Adaakus.
Regional Adainlctrator
U.S. Eavironaental Protection Agency, Region 5
77 West Jacksoa 'Blvd.
Chicago, n. 6O6O4

Dear Messrs. Fats and Adaakus:

The Department of the Interior has reviewed the proposed final
Record of Decision (ROD), dated April 22, 1996,  for the
explosives/Munitions Manufacturing Area operable Unit (EMMA oo)
at crab Orchard National Wildlife Refuge.

Because we have concluded that the selected reaedy is not
inconsistent with the requirements for reaedial action under the
National. Contingency Plan (MC$), we are concurring, with
reservations due to trust resource concerns, in the selected
reaedy as satisfying those portions of the Aray's CSRCLA
obligations addressed in sections 30O.1 through 300.525, and
300.700 through 3OO.B2S of the KCP.
        •
However, we wish to reiterate our strong conviction that it. will
likely be aore efficient—and aore cost-effective in the long
run—to incorporate actions that address natural resource
injuries into iapleaentation of the Army's reaedial action
obligations.  We strongly encourage the Aray, with the
cooperation of USEPA and Illinois EPA, to work closely with us
during the reaedial design phase in order to incorporate
appropriate activities that address natural resource daaages
liability and restoration obligations.  We are presently
evaluating what additional actions aay be necessary and
appropriate, in combination with the selected reaedy. to help
mitigate potential natural- resource injuries.  We will continue
to work with you now and during the remedial deei'gn phaee to
advise you of our relevant findings and proposed solutions.
Coordination between reaedial actions and trust resource concerns
usually leads to overall cost savings, even if it requires that
costs above the ainiaua reaediatlon requirements be  incurred in
the short tera.
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                             r IC.LJ.I J»Jl.l>- t ;
This concurrence does not constitute a determination concerning
injuries to natural resources at the EMMA OU resulting from
releases of hazardous substances, nor does it constitute a
determination of the degree to which the design and construction
of the selected remedy vill or will not mitigate injuries to
natural resources,  in addition to liability for response costs,
CERCLA liability includes liability for injury to, destruction
of, or loss of natural resources, including reasonable assessment
costs,  fie* 42 O.S.C. S 9€07(a)(4)(C); 43 C.P.R. Part 11 (1995).
As provided in both the Federal Facility Agreement and the
Memorandum: of Understanding with the Department: of the Army, the
Department has reserved its rights to assert natural resource
damages claims for this site.  Our concurrence in the selected
remedy does not represent a vaiver of those, rights -or a covenant
not to sue for natural resource damages', nor does implementation
of the ROD relieve the Army of its liability for.natural resource
The Department provisionally concurs with the conclusions of the
Baseline Risk Assessment in Section 7.3 of the ROD but advises
that, the baseline rick assessment differs substantially from a
natural resource damage assessment.  As the Federal trustee, the
Department, through the Fish and Wildlife service, is continuing
to evaluate potential injuries to natural resources at the site,
but has not completed a natural resource damage assessment.
Unlike the risk assessment, a natural resource damage assessment
determines the extent of injuries to natural resources resulting
from a hazardous substance release, and the cost of restoration.
                              Bonnie R. Cohen
                              Assistant secretary
                              Policy, Management and Budget
ce: Ms. Mary  Cade,• Director
    Illinois  Environmental  Protection Agency
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          State of Illinois

          ENVIRONMENTAL PROTECTION AGENCY

rtary A. Cade, Director                                    2200 Churchill Road, Springfield, IL 62794-9276

                          DECLARATION FOR THE RECORD OF DECISION

     SITE NAME AND LOCATION

     Crab Orchard National Wildlife Refuge, Explosives/Munitions Manufacturing Areas Operable Unit
     Marion, Illinois

     STATEMENT OF BASIS AND PURPOSE

     This decision document represents the Illinois Environmental Protection Agency's ("Illinois EPA's")
     concurrence on die selected remedial action for the Crab Orchard National Wildlife Refuge Superfund
     Site, Explosives/Munitions Manufacturing Areas Operable Unit  near Marion, Illinois. This decision
     document was developed in accordance with die Comprehensive Environmental Response, Compensation
     and Liability Act of 1980 ("CERCLA", as amended by the Superfund Amendments and Reauthorization
     Act of 1980 ("SARA"), and the extent practicable, die National Oil and Hazardous Substances Pollution
     Contingency Plan ("NCP").  This decision is based on the Administrative Record for this site.

     ASSESSMENT OF THE SITE

     Actual or threatened releases of hazardous substances from the sites in this operable unit, if not addressed
     by implementation of die response action selected in this Record of Decision ("ROD"), may present an
     imminent and substantial endangennent to the public health, welfare, or die environment

     DESCRIPTION OF THE REMEDY

     This remedy is intended to be die final action for die sites in this operable unit   For sites identified as
     COC-1, COC-2, COC-5, COC-7, COC-8, COC-9, COC-IO, COP-1, COP-2, COP-3  and Bunker Area 1-3,
     the ROD concludes no further action is required.   Due to uncertainties in die risk assessment, die site
     known as COC-4 has been deferred to a following operable unit to be named later by die Department of
     the Army.

     For die remaining sites known as COCO and COP-4, die remedy addresses all contaminated media and
     includes: removal and treatment of reactive soils, caver of contaminated soils and sediments, long-term
     maintenance and long-term groundwater monitoring.   The  major components of die selected remedy
     include:

     1.     Excavation and off-site treatment (incineration) and disposal of soils containing levels of explosive
           compounds greater titan  100,000 parts per million ("ppra") and lead greater than 450 ppm.
     2.     Additional removal of Royal Demolition Explosives (Hexahydro-l,3.5-trinitro-l,3.5-triazine)
           (RDX) and High Melting  Explosives (cyclotetramediylenetetranitnunine,  octahydro-1,3,5,7-
           tetranitro-l,3,5,7-tetrazocine) ("HMX") contaminated soil  at  Site COP-4 to a deptii of two feet
           below grade witiiin die existing fenced area and disposal in an off-site special waste landfill.
     3.     Sampling to  ensure remaining  affected soils at  COC-3  and COP-4 do  not  exhibit die
           characteristics  of a hazardous waste for lead and 2,4-Dinitrotoluene ("DNT").
     4.      Backfill excavated areas  to shape the base of die covers.
     5.      Placing a 24-inch clean soil cover over die remaining affected soils.
     6.      Long-term maintenance of the soil covers and monitoring to ensure protectiveness of die remedy.
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Declaration for the Record of Decision
Crab Orchard National Wildlife Refuge
Explosives/Munitions Manufacturing Areas Operable Unit
Page 2

STATUTORY DETERMINATIONS

The selected remedy is protective of human health and the environment, complies with the Federal and
State requirements mat are legally applicable at rdevant and appropriate to 6^ remedial action, and is cost
effective. This remedy utilizes permanent solutions and aheraative treatment technologies to the maximum
extent practicable and satisfies the statutory preference for remedies mat employ treatment that reduces
the toxicity, mobility, or volume as a principal element

Because the remedy, as described in this Declaration, will result in hazardous substances remaining on site
above health-based levels, a review will be conducted within five years after the commencement of
remedial action to ensure that the remedy continues to provide adequate protection of human health and
the environment
Maiy A. Gade, Director                                         Date'  /
Illinois Environmental Protection Agency
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