Superfund Record of Decision Alabama Army Ammunition Plant Operable Unit 5 Childersburg AL


                                    EPA/ROD/R04-97/021
                                    1997
EPA Superfund
     Record of Decision:
     ALABAMA ARMY AMMUNITION PLANT
     EPA ID: AL6210020008
     OU05
     CHILDERSBURG, AL
     03/27/1997

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                                                            Final Record of Decision
                                 RECORD OF DECISION

                           ALABAMA ARMY AMMUNITION PLANT
                                      Area A
                                    MARCH 1997

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       Final Record of Decision

             Prepared for:
     Alabama Army Ammunition Plant
         Childersburg, Alabama
                 Area A

              Prepared by:
Environmental Science & Engineering,  Inc.
          Gainesville, Florida

             January 1997

       ESE Project No. 3918359

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                                       Table of Contents

 Section                                                                                Page

 Declaration of the Record of Decision 	    1

 Decision Summary
 1.0  Site Name,  Location,  and Description 	    5
      1.1  Physiography 	    5
      1.2  Climate 	    5
      1.3  Surface Hydrology 	    5
      1.4  Geologic Setting 	    6
      1.5  Land Use 	    6
      1.6  Soils 	    6
      1.7  Groundwater 	    7
      1.8  Vegetation and Habitat/Community Structure 	    7

 2 . 0  Site History and Enforcement Activities 	   10

 3.0  Highlights of Community Participation 	   13
 3.1  Completed Interim Actions 	   13
      3 . 2  Proposed Final Action 	   13

4. 0    Scope and Role of the Area A Soil OU 	   15
      4.1  Completed Interim Actions 	   15
      4.2  Proposed Final Actions at Study Areas 13 and 14 	   15
      4 .3  Proposed No Further Action 	   16

 5.0  Summary of Site Characteristics 	   17
      5.1  Magazine Area (Study Area 11)  	   17
      5.2  Old Burning Ground (Study Area 12)  	   18
      5.3  Small Arms Ballistics Range (Study Area 13)  	   18
      5.4  Cannon Range (Study Area 14)  	   19
      5.5  Old Well (Study Area 15)  	   19
      5.6  Propellant Shipping Area (Study Area 17)  	   19
      5.7  New Trench Area (Study Area 30)  	   20
      5.8  Disposal Area (Study Area 31)  	   20
      5.9  Rubble Pile (Study Area 29)  and Number 2 Rubble Pile (Study Area 32)  	   21
      5.10 Henningsburg Area (Area 33)  	   21
      5.11 229 Area (Study Area 34)	   22

 6.0 Summary of Site Risks 	   23
      6.1  Introduction  	   23
      6.2  Health Risks  	   23
           6.2.1  Media of Concern 	   24
           6.2.2  COPCs 	   25
           6.2.3  Exposure Assessment 	   26
           6.2.4  Toxicity Assessment 	   32
           6.2.5  Risk Characterization 	   35
           6.2.6  Uncertainty Analysis 	   40

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                                 Table of Contents (continued)

7.0 Description of Remedial Alternatives 	  41
    7 .1  Study Area 13 Alternatives 	  41
         7.1.1  No Action  (Alternative 13-1)  	  41
         7.1.2  In Situ Bioremediation (Alternative 13-2)  	  42
         7.1.3  Excavation, Solvent Extraction, and Disposal (Onsite)  (Alternative 13-3) 42
         7.1.4  Excavation, Thermal Desorption, and Disposal (Onsite)  (Alternative 13-4) 42
         7.1.5  Excavation, Slurry Phase Bioremediation, and Disposal (Onsite)
                (Alternative 13-5)  	  43
         7.1.6  Excavation and Disposal (Offsite)  (Alternative 13-6)  	  43
    7 . 2  Study Area 14 Alternatives 	  43
         7.2.1  No Action  (Alternative 14-1)  	  43
         7.2.2  In Situ Bioremediation (Electrokinetic)  (Alternative 14-2)  	  43
         7.2.3  Excavation, Solidification/Stabilization,  and Disposal (Onsite)
                (Alternative 14-3)  	  44
         7.2.4  Excavation, Detoxification,  and Disposal (Onsite)  (Alternative 14-4)  ..  44
         7.2.5  Excavation, Acid Extraction,  and Disposal (Onsite)  (Alternative 14-5)..  45
         7.2.6  Excavation and Disposal (Offsite)  (Alternative 14-6)   	  45

8.0 Summary of the Comparative Analysis of Alternatives 	  46
    8.1  Threshold Criteria 	  46
         8.1.1  Overall Protection of Human Health and the Environment 	  46
         8.1.2  Compliance with ARARs 	  47

     8.2  Primary Balancing Criteria 	  49
          8.2.1  Short-Term Effectiveness 	  49
          8.2.2  Long-Term Effectiveness and Permanence 	  50
          8.2.3  Reduction of Contaminant MTV  	  50
          8.2.4  Implementability 	  50
          8.2.5  Cost 	  50
     8.3  Modifying Criteria 	  51
          8.3.1  ADEM/EPA Acceptance 	  51
          8.3.2  Community Acceptance 	  51

9.0  Selected Remedy and Remediation Levels 	  52
     9.1  Completed 1986 to 1987 Interim Action 	  52
     9.2  Completed 1994 Interim Action 	  54
     9. 3  Proposed Final Action 	  55

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                                  Table of Contents (continued)

 10.0 Statutory Determinations 	   57
      10.1  Completed 1986 to 1987 Interim Action 	   57
            10.1.1  Protection of Human Health and the Environment 	   58
            10.1.2  Compliance with ARARs 	   58
            10.1.3  Cost Effectiveness 	   59
            10.1.4  Use of Permanent Solutions and Alternative Treatment Technologies
                    or Resource Recovery Technologies to the Maximum Extent Practicable   59
            10.1.5  Preference for Treatment as a Principal Element 	   60
      10.2  Completed Interim Action for Study Areas 12 and 30  	   60
            10.2.1  Protection of Human Health and the Environment 	   60
            10.2.2  Compliance with ARARs 	   61
            10.2.3  Cost Effectiveness 	   62
            10.2.4  Use of Permanent Solutions and Alternative Treatment Technologies
                    or Resource Recovery Technologies to the Maximum Extent Practicable   63
            10.2.5  Preference for Treatment as a Principal Element 	   63
      10.3  Proposed Final Action 	   64
            10.3.1  Protection of Human Health and the Environment 	   64
            10.3.2  Compliance with ARARs 	   64
            10.3.3  Cost Effectiveness 	   66
            10.3.4  Use of Permanent Solutions and Alternative Treatment Technologies
                    or Resource Recovery Technologies to the Maximum Extent Practicable   66
            10.3.5  Preference for Treatment as a Principal Element 	   67

 11.0 Documentation of Significant Changes 	   68

 12 . 0 References 	   69

 Responsiveness Summary 	   71

 1.0   Overview 	   71
 2.0   Background on Community Involvement 	   71
 3.0   Summary of Public Comment and Agency Response 	   72
 4.0   Remaining Concerns 	   72

          List of Tables

Table 1   ALAAP Study Areas
Table 2   Summary of Chemicals of Potential Concern (COPCs) at ALAAP Area A
Table 3   Chronic Oral and Inhalation RfDs for the COPCs at ALAAP Area A
Table 4   CSFs and WoEs for the Known/Potential Carcinogenic COPCs at ALAAP Area A
Table 5   Summary of Media and Chemicals of Concern (COCs)  Exceeding Human Health
          Risks of 10 -6 and Hazard Indices (His)  of 0.1
Table 6   Summary of Media and Chemicals of Concern (COCs)  Exceeding Terrestrial and
          Aguatic Ecological Toxicity Quotients (EQs)
Table 7   Uncertainties in the Human Risk Assessment Process
Table 8   Uncertainties in the Ecological Risk Assessment Process

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          List of Figures

Figure 1  Location Map of ALAAP
Figure 2  ALAAP Area A/B Division
Figure 3  Study Areas Within Area A

          List of Acronyms and Abbreviations

AAC       Alabama Administrative Code
ADEM      Alabama Department of Environmental Management
ADEM      Alabama Department of Environmental Management
ALAAP     Alabama Army Ammunition Plant ALAAP
BRA       Baseline Risk Assessment
CAA       Clean Air Act
CERCLA    Comprehensive Environmental Response, Compensation, and Liability Act
cm        centimeters
COG       chemical of concern
COPC      chemical of potential concern
CRP       Community Relations Plan
CSF       cancer slope factor
5C        degrees Celsius
5F        degrees Fahrenheit
DNT       dinitrotoluene
DOD       Department of Defense
EPA       U.S. Environmental Protection Agency
ESE       Environmental Science & Engineering, Inc.
FS        feasibility study
ft        foot
ft-msl    feet above mean sea level
gal       gallon
GOCO      government-owned/contractor-operated
gpm       gallons per minute
ha        hectares
HEAST     Health Effects Assessment Summary Tables
HI        hazard index
IEUBK     Integrated Exposure Uptake Biokinetic
IOC       inorganic chemical
IRIS      Integrated Risk Information System
IRP       Installation Restoration Program
km        kilometer
km 2      sguare kilometers
LOEC      lowest-observed-effect concentration
m         meters
MCL       maximum contaminant level
mg/kg     milligrams per kilogram
mg/kg/day milligram per kilogram per day
NC        nitrocellulose
NCP       National Oil and Hazardous Substances Pollution Contingency Plan
NPL       National Priorities List

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ORNL      Oak Ridge National Laboratory
OSHA      Occupational Safety and Health Act
OU        operable unit
PAH       polycyclic aromatic hydrocarbon
PbB       blood-lead
PPE       personal protection equipment
PPLV      preliminary pollutant limit value
PPM       parts per million
RA        risk assessment
RCRA      Resource Conservation and Recovery Act
RDA       recommended daily allowance
RfD       reference dose
RI        remedial investigation
RI/FS     remedial investigation/feasibility study
RMCS      retrievable monitored containment structure
ROD       Record of Decision
RPM       remedial project manager
SARA      Superfund Amendments and Reauthorization Act of 1986
SVOC      semi-volatile organic compound
tetryl    2,4,6-trinitropheny/methylnitramine
TNT       trinitrotoluene
TSS       total suspended solids
Ig/g      micrograms per gram
UR        unit risk
USAGE     U.S. Army Corps of Engineers
USAEC     U.S. Army Environmental Center
USATHAMA  U.S. Army Toxic and Hazardous Materials Agency
USC       United States Code
USDA      U.S. Department of Agriculture
VOC       volatile organic compound
Weston    Roy F. Weston, Inc.
WoE       weight-of-evidence
WWII      World War II
yd        yard
yd 3      cubic yard

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DECLARATION OF THE RECORD OF DECISION

SITE NAME AND LOCATION

Alabama Army Ammunition Plant
16559 Plant Road
Childersburg, Alabama 35044-0368

STATEMENT OF BASIS AND PURPOSE

This decision document presents the selected final remedial action for the soils and groundwater
of Area A at Alabama Army Ammunition Plant (ALAAP), Childersburg, Alabama, which was chosen in
accordance with the Comprehensive Environmental Response, Compensation, and Liability Act
(CERCLA), as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA), and, to
the extent practicable, the National Oil and Hazardous Substances Pollution Contingency Plan
(NCP). This decision is based on the administrative record for the site.

Remedial investigations have progressed at the site since 1980. A soil removal action addressing
all identified contaminated soils was begun prior to the site being placed on the National
Priorities List (NPL). Following the removal action, additional sampling was conducted to verify
completeness. This sampling identified additional areas reguiring remediation and an interim
response action was performed. Following all interim response actions, a supplemental
investigation was completed to determine the contamination status of all media (soil,
groundwater, surface waters, sediments) at the site following remediation. Samples were
collected from all study areas, including those that had undergone interim removal actions.
Based on this new data, a Final Remedial Investigation Report and Risk Assessment were completed
utilizing the data collected during the supplemental investigation along with previously
collected data. Based on this complete data set of the site as it exists now, the Risk
Assessment determined that the only sites which still presented an unacceptable human health
risk were Study Areas 13 and 14. Interim response actions completed at other study areas were
determined to be sufficient to be protective of human health, welfare and the environment. All
other media at all other study areas at the site have been approved for No Further Action.

This final ROD for Area A of ALAAP presents the preferred alternatives for contaminated soils
within Study Areas 13 and 14. This document also presents an evaluation of the previous removal
action and the interim response action with respects to all statutory criteria. Although the
soil removal action was not reguired to meet the nine criteria as it was begun prior to NPL
listing, this document presents an evaluation of the criteria for completeness of the record.

This final remedial action (Study Areas 13 and 14) is being taken to protect human health and
the environment from unacceptable risks. This action is the final action for all media within
Area A. All other Study Areas within Area A have been approved for No Further Action.

The U.S. Environmental Protection Agency (EPA) and the State of Alabama concur with the
selected remedy.

ASSESSMENT OF THE SITE

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

DESCRIPTION OF THE SELECTED REMEDIES

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Completed Actions

The Stockpile Soils Area OU, the first OU to address contaminated soils at ALAAP Area A,
involved treating contaminated soils that were excavated from Area A and stored in retrievable
monitored containment structures (RMCSs) in Area B. The initial remedial actions that led to the
soils stockpiling were performed based on findings of the remedial investigation/feasibility
study (RI/FS) of ALAAP completed in 1986. Cleanup activities at Area A included building
decontamination and demolition and contaminated soil excavation and treatment. An interim ROD
for treatment [i.e., incineration followed by solidification/stabilization (if reguired)] of the
Stockpile Soils Area OU soils was signed on December 31, 1991. In 1990, EPA indicated that
additional investigations needed to be conducted at Area A to ensure that no residual
contamination remained on site; therefore, a supplemental remedial investigation (RI) was begun
in 1991. Additional soils were removed and treated from Study Areas 12 and 30 based on initial
results of the supplemental investigation. The final supplemental RI was completed in 1996. This
investigation included a sampling of all media following completed remedial actions. This data
set shows the site as is and was the basis for the completed Risk Assessment.

Donald F. Hurley, Jr. Date
Major OD
Commanding, Alabama Army Ammunition Plant

Proposed Final Actions

This Final Area A ROD addresses the last remaining principal threats from lead and semivolatile
contamination by excavating and treating the newly identified contaminated soils from Study
Areas 13 and 14 of Area A. Treatment of these contaminated soils will be offsite incineration of
soils from Study Area 13 and solidification/stabilization of lead-contaminated soils from Study
Area 14. The scope of action of this final ROD is limited to the soils of Study Area 13 and 14,
acknowledges the interim response actions which have taken place prior to this document and is
intended to be the final ROD for Area A actions. A Final Baseline Risk Assessment (RA) and
Feasibility Study (FS) were developed upon completion of the final additional sampling at ALAAP
Area A. The sampling effort was initiated to screen the site as a whole, post remedial action,
to address soils not previously sampled for full scan analysis and to establish the background
levels at Area A.

The major components of the selected remedy for the soils of Study Area 13 and 14 within Area A
include:

• Excavation of approximately 12 cubic yards of Benzo(a)pyrene-contaminated soils
from Study Area 13 and 46 cubic yards of lead-contaminated soils from Study Area 14
of Area A;
• Transportation of Benzo(a)pyrene contaminated soils from Area 13 to an off-site
hazardous waste incinerator;
• Excavation and on-site treatment (in Area B) by solidification/stabilization of
soils from Area 14.

The Risk Assessment completed for the site, based on data collected after the completion of all
interim response actions, determined that all remaining study areas within Area A gualified for
No Further Action.

STATUTORY DETERMINATIONS

This final action is protective of human health and the environment, complies with Federal and
State reguirements that are legally applicable or relevant and appropriate for this limited

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scope remedial action, and is cost-effective. This final action fully addresses the statutory
mandate for permanence and treatment to the maximum extent practicable, and employs a treatment
that reduces toxicity, mobility or volume as a principal element. Actual or threatened releases
from Study Areas 13 and 14 of Area A, if not addressed by implementing the response action
selected in this ROD, may present a current or potential threat to public health, welfare or the
environment. All ARARs for the site will have been met for all Study Areas once the removal
action at Study Areas 13 and 14 have been completed. As this remedy will not result in hazardous
substances remaining onsite in Area A above health based levels, the 5-year review will not
apply to this action.

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                               RECORD OF DECISION

                        ALABAMA ARMY AMMUNITION PLANT
                                     Area A

                                  JANUARY 1997
Mr. Raymond J. Fatz                                                Date
Acting Deputy Assistant Secretary of the Army
 (Environment, Safety, and Occupational Health)

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DECISION SUMMARY

1.0 Site Name, Location, and Description

Alabama Army Ammunition Plant (ALAAP) is located in Talladega County in east-central Alabama, 30
miles east-southeast of Birmingham and 70 miles north of Montgomery, the State capital (Figure
1). The nearest town is Childersburg, Alabama, which is four miles south of ALAAP.

1.1 Physiography

ALAAP is located in the Coosa Valley and Ridge physiographic province [Environmental Science
& Engineering, Inc. (ESE), 1986]. The border between the Valley and Ridge province and the
Piedmont province is south of ALAAP between Talladega and Tallaseehatchee creeks. The terrain
is level-to-rolling and largely suited to pasture and timberland, with elevations ranging from
117 to 183 meters (m) [384 to 600 feet above mean sea level (ft-msl)]. The bedrock underlying
ALAAP has been mapped on a regional scale by Shaw [1970, 1973] and identified as undiffer-
entiated Knox Group of Upper Cambrian to lower Ordovician age dolomite.

1.2 Climate

The climate in Talladega County is temperate; during fall, winter, and spring, the weather is
controlled by frontal systems and contrasting air masses. Summer weather, which lasts from May
or June until September or October, is almost subtropical, since maritime tropical air prevails
along Bermuda high-pressure systems [ESE, 1981].

Average daily temperatures in the region are 24 degrees Celsius (C) [75 degrees Fahrenheit (5F)]
for the high and 105C (505F) for the low. Summer high temperatures are commonly 325C or
above, occasionally exceeding 385C.

Mean monthly rainfall is 5.5 centimeters (cm). The highest average monthly rainfall is 16.3 cm
(6.4 inches), occurring in March. Talladega County has two annual rainy seasons. The winter
rainy season is from December to April, and the summer rainy season lasts from May through
September, with the highest rainfall occurring in June and July.

1.3 Surface Hydrology

Surface water flow at the site is in a general westerly direction, from ALAAP toward the Coosa
River. The surface water from Area A drains to Area B along the border, (Figure 2) resulting in
potential contaminant migration from surficial soil contamination at Area A. A small portion of
the southeast and east side of ALAAP drains toward Talladega Creek, a tributary of the Coosa
River, Prior to construction of ALAAP, the area consisted of farms, woodlands, and wetlands.
Much of the western half of ALAAP was poorly drained. Small natural drainage ways were enlarged
and rerouted to provide drainage at the sites of the various manufacturing operations. During
site manufacturing operations, liguid industrial waste from the explosives manufacturing was
conveyed west to the Coosa River by a manmade channel, the Red Water Ditch. No natural ponds
existed on ALAAP during its operation. Two large storage lagoons were constructed to retain
industrial wastes (Area B). Extensive wooded swamp and open pond areas have developed in the
drainage systems at ALAAP since the beginning of demolition activities in 1973, mostly as a
result of damming of drainways by beavers.

1.4 Geologic Setting

The bedrock underlying ALAAP has been mapped on a regional scale and has been identified as
the undifferentiated Knox group of Upper Cambrian to Lower Ordovician age dolomite. The dolomite

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underlying ALAAP is thick-to-medium-bedded, cherty, and penetrated by numerous cavities, joints,
and fractures. The dolomite is overlain by residual soil derived from weathering processes. This
soil matrix consists primarily of clay, with some silt, sand, and occasional chert boulders, and
varies in thickness from less than 3 feet to more than 80 feet.

1.5 Land Use

ALAAP Area A is currently privately owned under an unrestricted deed with controlled access.
The only activity occurring on ALAAP Area A is managed wildlife activity. Future land use of
the ALAAP Area A property is expected to consist of wildlife habitat, hunting grounds, and
occasional logging of wooded areas although the deed permits unrestricted usage.

1.6 Soils

The soils at ALAAP (Areas A and B) are generally divided into three associations. Soils of the
Bodine-Minvale Association are found on the high ground of the eastern portion of ALAAP. This
association is composed of deep, well-drained, steep, cherty, medium-textured soils derived from
limestone and dolomite. Most of ALAAP is covered by soils of the Decatur-Dewey-Fullerton
Association, which are also deep, well-drained, loam soils derived from limestone and dolomite.
The soils of the floodplains of Talladega Creek and the Coosa River have been classified as the
Chewacla-Chenneby-McQueen Association. These are deep, nearly level, alluvial loam soils that
grade from somewhat poorly drained to well-drained and are subject to flooding.

These broad-based associations represent agricultural classifications rather than engineering
descriptions. Soil constitution at ALAAP, and thus within Area A, lie within the three
associations that range from soils consisting mainly of sand and silt with little clay to soils
made up entirely of clay.

1.7 Groundwater

Groundwater from the dolomite aguifer of the Coosa Valley supplies the potable needs of the
communities, homes, farms, woodlands and wetlands. Most of the wells draw water from solution
cracks and cavities in the dolomite [ESE, 1981]. A few wells are finished in the residual soil,
but these wells are less productive than those drilled into the dolomite. Groundwater in the
surficial aguifer flows to the west-southwest or toward Area B at 7.31 meters per year [ESE,
1986].

1.8 Vegetation and Habitat/Community Structure

The environment at ALAAP has had 3 major perturbations in the past 40 years (agriculture,
military operations, and woodland management). Prior to construction of the ALAAP facilities,
the area was primarily cropland and woodland. Since the cessation of operations at ALAAP, a
woodland management program was instituted that extensively modified the former demolition
areas by allowing for planting of 1,381 hectares (ha) (3,411 acres). Currently, most of the
formerly maintained drainages, pine plantations, and cleared areas have under-gone considerable
vegetative overgrowth. The major existing vegetative systems are grassland/old field
association, upland pine forest, oak forests, low moist pine woods and hardwood swamps [ESE,
1986].

Past and current land management activities, to a large degree, are responsible for the species
composition of Area A. Relative areas and vegetative community types for sites in Area A have
been estimated based on observations during 1991 ecological surveys by ESE. Since deactivation
of industrial operations on the installation, much of the land in Area A has been managed for
the production of pine resources. In recent times, small, isolated areas have been disturbed in

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the process of decontaminating industrial sites; these areas were subsequently abandoned. They
became colonized with early successional species and, in the short-term, support fewer primary
producers. Consequently, they are of limited use as wildlife habitat. More recently, heavy
loqqinq and clearcuttinq of pines has occurred. These clearcuts are beinq reveqetated with
wildlife foraqe and cover crops that favor qame species. The existinq pine stands have been
manaqed as densely qrown pine plantations or less dense pine stands supportinq old field and
early successional herbaceous and shrub species at the qround stratum. Much of the qround cover
is dominated by Japanese honeysuckle (Lonicera japonica) and blackberry (Rubus sp.).

More natural communities occur and still remain alonq drainaqe features, a reflection of less
intense manaqement qeared toward pine production. Dominant or common tree species occurrinq
in these communities include red oak (Quercus rubra), white oak (Q. alba), sweetqum
(Liquidambar styraciflua), American beech (Faqus qrandiflora), flowerinq doqwood (Cornus
florida), hickories (Carya spp.), water oak (Q. niqra) and laurel oak (Q. laurifolia).
Associated shrub and herbaceous veqetation are also supported alonq relatively undisturbed
drainaqes. A more complete description of communities and species composition is included in the
Area B RI/FS document [ESE, 1990]. Section 5.0 (Critical Habitat) of the RI/FS addressed
ecoloqical composition of Areas A and B and includes a list of veqetation, communities, and
habitats [ESE, 1990].

Hardwood swamps occur throuqhout and have been affected by past loqqinq practices. Some hardwood
swamps are remnants of natural systems, but others have become established in areas where
chanqes in the hydroloqy have occurred. These hydroloqic chanqes are a result of either
human-induced factors or beaver activity, which has created more hydric conditions favorinq the
establishment of wetland species. Natural hardwood swamps onsite support mature tree stands.
Those more affected by loqqinq activities are covered with younqer trees. Hardwood swamps onsite
are dominated by red maple, box-elder, pop ash, suqarberry, winqed elm, sweetqum, parsley haw
and red haw. Common shrubs include buttonbush and willow. A mature bottomland hardwood swamp is
a prominent feature of Study Area 11. Within this site, surface water drains internally to the
low-lyinq area that is the swamp. Standinq water is present durinq the wet season.

Hardwood knolls also occur and are dominated by hardwood tree species and support fewer pine
species. The deqree of canopy cover is variable and in part determines the density and species
composition of herbaceous and shrub stratum veqetation.

Old field communities exist in different deqrees of succession. Study Area 30 is relatively
natural in its reestablishment and represents a younq community. This area was recently
disturbed (1988) durinq mitiqation activities. Durinq investiqation activities, the veqetation
composition in this old field community was characterized to reflect backqround conditions for
comparison with other similar systems that were known to be contaminated. Other areas that have
also been recently disturbed reflect different species composition and diversity because of aqe
(time since disturbance) and deqree of manaqement. This is apparent at Study Areas 31 (Disposal
Area) and 13 (Small Arms Ballistics Ranqe). Conditions at Study Area 31 reflect expanses of bare
qround; or a result of recent disturbance or contaminated conditions, preventinq reveqetation;
or both. Study Area 13 reflects a much less diverse system because of manaqement disturbances.
Here, much of the area is veqetated by Lespideza, which was planted for wildlife. This plant
species dominates the area and excludes the occurrence of other species.

Several areas within Area A are beinq manaqed for production of local qame species. Foraqe and
cover veqetation has been planted in disturbed field communities and alonq roadsides in Area A.
Species qrown for wildlife use include two species of Lespideza, white and red clover, cowpeas,
Austrian winter peas, oats, rye, wheat, sorqhum, hairy vetch, bahia qrass, browntop millet and
sawtooth oak. Lespideza is the most commonly used species and is a tall qrowinq herb that
excludes most native species once established.

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Shrub and thicket communities are found throughout the site. They have grown up along drainage
features, forested edges, and the edges along permanent roadways and logging roads. These
thickets are composed of shrub species, including smooth sumac (Rhus glabra), wax myrtle (Myrica
cerifera), saplings of common tree species, vines including honeysuckle and briars (Smilax sp.),
and blackberry.

2.0 Site History and Enforcement Activities

ALAAP was established on 13,233 acres of land near the junction of Talladega Creek and the Coosa
River. The plant was built in 1941 and operated during World War II (WWII) as a government-
owned/contractor-operated (GOCO) facility. ALAAP produced nitrocellulose (NC), single-based
smokeless powder, and nitroaromatic explosives [i.e., trinitrotoluene (TNT), dinitrotoluene
(DNT); and 2,4,6-trinitrophenylmethylnitramine (tetryl)]. Activities at ALAAP included in the
manufacture of explosives were the production of the chemicals sulfuric acid H 2 SO 4), aniline,
N,N-dimethylaniline, and diphenylamine. Spent acids were recycled and wastes resulting from
these operations were disposed of. In August 1945, operations were terminated at ALAAP and the
plant was converted to standby status.

The plant was maintained in various stages of standby status until the early 1970s. In 1973, the
Army declared ALAAP excess to its needs. Since that time, several parcels of the original
property, including Area A, were sold or returned to their previous owners. Area A, encompassing
2,714 acres, was auctioned by GSA in May 1990. Currently the property consists of wildlife
habitat used occasionally for hunting and some logging. The property was sold with an
unrestricted deed.

In 1978, the U.S. Army Environmental Center [formerly the U.S. Army Toxic and Hazardous
Materials Agency (USATHAMA)], managing the Army's Installation Restoration Program (IRP),
conducted a record search which concluded that specific areas of the facility were potentially
contaminated by explosives and lead compounds. Further studies at ALAAP confirmed soils
contamination with explosives compounds, asbestos, and lead. Several investigations were
conducted between 1981 and 1983 to define contamination further. In 1984, ALAAP was proposed for
inclusion on the CERCLA (Superfund) National Priorities List (NPL).

An RI/FS under the Department of Defense (DOD) IRP was initiated in 1985 to determine the nature
and extent of contamination at ALAAP and the alternatives available to clean up the site. For
the purposes of the RI/FS, the facility was divided into two general areas. Area A consisted of
the eastern portion of the facility, and Area B consisted of the western portion. The initial RI
under the IRP confirmed the existence of explosives, asbestos, and lead contamination in the
soil in Area A, and in the soil, sediment, and groundwater in Area B. The RI for Areas A and B
was completed in 1986. As a result of the findings of the RI, cleanup activities at Area A were
conducted in 1986 and 1987, which included building decontamination and demolition, soil
excavation, and stockpiling. Initially, 21,400 cubic yards of contaminated soils were excavated
from Area A and stockpiled in Area B in 2 covered buildings and on a concrete slab. In July
1987, ALAAP was placed on the NPL.

Area A includes the Magazine Area (Study Area 11), Old Burning Ground (Study Area 12), Small
Arms Ballistic Range (Study Area 13), Cannon Range (Study Area 14), Old Well (Study Area 15),
the eastern portion of the Propellant Shipping Area (Study Area 17) and a parcel of woodland
outside the security fenceline. Additional areas identified during subseguent investigations
conducted at the site include the Rubble Pile (Study Area 29), the New Trench Area (Study Area
30), the Disposal Area (Study Area 31), the Number 2 Rubble Pile (Study Area 32), the
Henningsburg Area (Study Area 33) and the 229 Area (Study Area 34). An overall layout of Area A
showing the locations of all study areas is presented in Figure 3. The study areas within Area A

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and their descriptions are presented in Table 1.

In 1990, EPA indicated that additional investigations needed to be conducted at Area A to ensure
that no residual contamination remained following the initial removal actions. Area A was
conveyed to private buyers in August 1990, with the provision that additional investigations and
any reguired cleanups would be performed by the Army.

In 1991, a supplemental RI was begun to verify the effectiveness of the completed removal
actions in Area A. The supplemental RI initially determined that soils at two study areas within
Area A (Study Areas 12 and 30) continued to contain lead and explosives at unacceptable
concentrations. The supplemental RI/FS concluded that approximately 2,200 cubic yards of
lead-contaminated soil from Study Area 12 and approximately 5 cubic yards of explosives-
contaminated soil from Study Area 30 reguired further remediation.

A Record of Decision (ROD) for the Stockpile Soils Operable Unit (OU) was issued in December
1991 and recommended incineration as the preferred alternative. The incineration of the
Stockpile Soils commenced in May 1994 and was completed in August 1994.

An interim ROD for the Area A Soil OU (Study Areas 12 and 30) was submitted in April 1994.
During the latter half of 1994, Study Area 12 soils (2,179 cubic yards) were excavated,
stabilized and placed on the on-site backfill area in Area B. Explosives contaminated soils from
Study Area 30 (5 cubic yards) were excavated, incinerated and placed in the on-site backfill
area in Area B.

Following completion of the interim response actions, samples of all media across the site were
collected. This sampling provided a complete assessment of the status of the site following the
completed remedial actions. This data was the basis for the Risk Assessment.

The following documents outline the results of the initial assessment of ALAAP, cleanup actions
conducted in Area A, and the investigations of the Area A. More detailed information is
available in documents for public review at the Earle A. Rainwater Memorial Library,
Childersburg, Alabama.

1. Installation Assessment of Alabama Army Ammunition Plant, Report 130, May 1978.
2. Alabama Army Ammunition Plant, Area A Remedial Actions, Final Report, February
1988.
3. Stockpile Characterization Report for Alabama Army Ammunition Plant, Childersburg,
Alabama, July 1991.
4. Feasibility Study for the Alabama Army Ammunition Plant Stockpile Area, October
1991.
5. Proposed Plan for Early Remedial Action of Stockpile Soils at Alabama Army
Ammunition Plant Stockpile Soils Area OU, November 1991.
6. ROD for Early Remedial Action of Stockpile Soils at Alabama Army Ammunition
Plant Stockpile Soils Area OU, December 1991.
7. Supplemental Remedial Investigation/Feasibility Study for Area A, Alabama Army
Ammunition Plant, Final Baseline Risk Assessment, August 1995.
8. Supplemental Remedial Investigation/Feasibility Study for Area A, Alabama Army
Ammunition Plant, Final Feasibility Study, February 1996.
9. Interim ROD for Soils within the Alabama Army Ammunition Plant Study Areas 12
and 30 of the Area A Soils OU.
10. Supplemental Remedial Investigation/Feasibility Study for Area A, Alabama Army
Ammunition Plant, Final Remedial Investigation Report, May 1996.
11. Supplemental Remedial Investigation/Feasibility Study for Area A, Alabama Army
Ammunition Plant, Remedial Investigation Report Addendum, Low-Flow

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             Purge/Sampling of Selected Wells, August 1996.
         12. Final Proposed Plan for Remedial Action of Contaminated Soils at the Alabama Army
             Ammunition Plant Area A, August 1996.

3.0 Highlights of Community Participation

In accordance with the Army's Community Relations Plan  (CRP) for ALAAP, October 1990, all
decision documents were released to the public for review and comment. All documents were
made available to the public at the Earle A. Rainwater Memorial Library, Childersburg, AL.

3.1 Completed Interim Actions

The FS and the Proposed Plan for the Areas 12 and 30 ROD were released to the public on March
31, 1993. The public comment period started on April 1, 1993, and ended on April 30, 1993. The
notice of availability of the Proposed Plan was published in Daily Home, Birmingham News,
Anniston Star, and Montgomery Advertiser on March 30, 1993.

In accordance with the CRP, a public meeting was held at Central Alabama Community College on
April 20, 1993 to inform the public of the preferred alternative and to seek public comments.
At this meeting, representatives from ALAAP, EPA, the Alabama Department of Environmental
Management  (ADEM), the U.S. Army Corps of Engineers  (USAGE), and U.S. Army Environmental Center
(USAEC) were present and answered guestions about the site and the remedial alternatives under
consideration. ALAAP, EPA, ADEM, USAGE, and the USAEC reviewed all written and verbal comments
submitted during the public comment period. Review of these comments caused no significant
changes to the preferred remedy outlined in the Proposed Plan. A response summary to the public
comments received during the public comment period and hearing was included in the
Responsiveness Summary section of the ROD for Areas 12 and 30.

The Proposed Plan identified Alternative ID as the preferred remedy. Alternative ID, which was
described in the FS, consists of excavation of Area A contaminated soils, transportation to
Area B, storage with stockpiled soils, on-site treatment (in Area B) along with the stockpiled
soils, and on-site disposal of treated soils at a designated area in Area B.

3.2 Proposed Final Action

The FS and the Proposed Plan for the final ROD were released to the public on August 16, 1996.
The public comment period started on August 16, 1996, and ended on September 15, 1996. Documents
were made available to the public at the Earle A. Rainwater Memorial Library, Childersburg, AL.
The notice of availability of the Proposed Plan was published in the Daily Home and the
Birmingham News on August 15, 1996.

In accordance with the CRP, a public meeting was held at Central Alabama Community College
on September 10, 1996 to inform the public of the preferred alternative and to seek public
comments. At this meeting, representatives from ALAAP, EPA, the Alabama Department of
Environmental Management  (ADEM), the USAGE, and USAEC were present and answered guestions about
the site and the remedial alternatives under consideration. A response summary to the public
comments received during the public comment period and hearing is included in the Responsiveness
Summary section of this report.

The Proposed Plan identified Alternative 13-6 as the preferred remedy for soils within Study
Area 13 and Alternative 14-3 as the preferred alternative for contaminated soils within Study
Area 14. Alternative 13-6, which is described in the FS, consists of excavation of contaminated
soils and transportation to a hazardous waste landfill for incineration. Alternative 14-3, which
is described in the FS, consists of excavation of all contaminated soils followed by solidifica-

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tion/stabilization of soils prior to on-site disposal. These actions are a final action for all
media within Area A. The Risk Assessment completed for the site, based on data collected after
the completion of all interim response actions, determined that all remaining study areas
qualified for No Further Action.

ALAAP, EPA, ADEM, USAGE, and the USAEC reviewed all written and verbal comments submitted during
the public comment period. Review of these comments caused no significant changes to the
preferred remedy outlined in the Proposed Plan. All questions, either written or verbally
presented in the public meeting have been addressed.

4.0 Scope and Role of the Area A Soil OU

OUs are defined as discrete actions that comprise incremental steps toward the final overall
remedy. These actions may completely address a geographic portion of a site or a specific
problem. OUs may also be interim actions; however, they must be followed by subsequent actions
to address the scope of the problem definitely. This document addresses both completed interim
actions and proposed final actions at the installation.

4.1 Completed Interim Actions

The Stockpile Soils Area OU, the first OU to address contaminated soils at ALAAP Area A,
involved treatment of contaminated soils that were excavated, from Area A and stored in RMCSs
in Area B. The initial removal actions that led to the soils stockpiling were performed based on
findings of the RI/FS of ALAAP completed in 1986. Cleanup activities at Area A included building
decontamination and demolition and contaminated soil excavation and stockpiling. A ROD for
treatment [i.e., incineration followed by solidification/stabilization (if required)] of the
Stockpile Soils Area OU soils was signed on December 31, 1991. In 1990, EPA indicated that
additional investigations needed to be conducted at Area A to ensure that no residual
contamination remained on site; therefore, a supplemental RI was conducted in 1991. An interim
action covering soils of Study Areas 12 and 30 within Area A addressed the contaminated soils
that were identified during the initial supplemental investigation.

The contaminated soils of the Stockpile Soils Area OU as well as soils from Study Areas 12 and
30 within have been remediated. Onsite incineration was the selected remedy in the ROD for the
Stockpile Soils Area OU and for the soils removed from Area 30. The ash from the incinerator
was tested for lead contamination and treated by solidification/stabilization (if required)
prior to final disposal. Soils removed from Study Area 12 during the interim action have also
been solidified.

4.2 Proposed Final Actions at Study Areas 13 and 14

The action proposed in this plan is a final action and is intended to address all remaining
contaminated soils (Study Areas 13 and 14) within Area A. The threats addressed in this final
remedial action are the contaminated soils located at Study Areas 13 and 14. Actual or
threatened release of hazardous substances from these contaminated soils, if not addressed by
implementing the selected early action, may present a current or potential threat to public
health, welfare, and the environment. Following completion of these actions, there will be no
remaining media within Area A requiring action. This action represents the final action to be
completed at the site.

4.3 Proposed No Further Action

The sampling associated with the supplemental investigation provided a completed assessment of
all media as it exists following the completion of all interim response actions. This data set

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was the basis for the completed Risk Assessment for the site. The Risk Assessment has determined
that all remaining Study Areas, with the exception of those presented in Section 4.2 (Study
Areas 13 and 14), qualify for No Further Action.

5.0 Summary of Site Characteristics

Remedial investigations at the site have been completed in several phases. Early investigations
focused on determining the horizontal and vertical extent of contamination within the soils and
groundwater. These initial investigations were the basis for the interim response actions
completed at the site. Following completion of an interim action, samples were once again
collected from the affected study areas to verify that the actions completed were effective.
This verification sampling led to the interim action completed at Study Areas 12 and 30 where
additional contamination was detected. Following the completion of this (Areas 12 and 30)
interim action, samples were once again collected from across the entire installation to
determine if any final actions were required prior to site closure. As a part of this effort,
samples from all site media were collected. Table 2 presents a summary of the average detected
background concentrations of inorganics compared to the average detected concentrations detected
at each Study Area. These supplemental data were the basis for completing the final Baseline
Risk Assessment (BRA) for the site. The final BRA was prepared to assess the impact(s) of the
contaminants at each site on human and environmental concerns and to determine appropriate
remediation levels. The BRA identified Area 13 and 14 as requiring additional remedial actions.
These are the only areas identified as still having contamination present in the soils exceeding
health based cleanup levels. A summary of chemicals of potential concern (COPCs) detected at
each area is presented in Table 3.

The following discussion summarizes the site characteristics for each study area and includes a
description of the fate and transport of site contaminants. This summary is based on the
supplemental data collected following the initial removal actions across all of Area A and the
interim actions completed in Areas 12 and 30. These data are post removal and reflect the
effectiveness of interim response actions completed to date.

5.1 Magazine Area (Study Area 11)

The Magazine Area, located in the north central portion of Area A and consisting of a series of
storage buildings, is the largest study area in ALAAP Area A. The Series 260 Buildings are
designated for storing DNT, the Series 1010 Buildings for storing tetryl, and the Series 811
Buildings for storing TNT.

Soils, groundwater, surface water and sediments were analyzed. Metals concentrations were
detected in all media, and polycyclic aromatic hydrocarbons (PAHs) were also present in the
soil. Minor concentrations of volatile contaminants (trichloroflouormethane) were detected in
soil and sediment samples. The primary migration pathways of contaminants detected in soil are
fugitive dust or particulate emission, contact, and ingestion. In addition, due to the proximity
of a hardwood swamp near Study Area 11, the potential exists for chemicals in soil to migrate to
the swamp via surface runoff during periods of heavy rainfall.

5.2 Old Burning Ground (Study Area 12)

This study area is located in the northern section of Area A and was the primary disposal site
for unacceptable batches of explosives, propellants, and other reactive wastes. Periodic burning
of the study area's vegetation was practiced during plant operation to minimize the danger of
wildfires. This study area also included a former Lead Remelt Facility. Surface water flow in
this area is intermittent and occurs only during heavy rain events. Two interim response actions
have been completed at this site to address explosives and lead contamination.

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Supplemental sampling has been completed in this area to verify the effectiveness of the
completed remedial actions. Organic and metallic chemicals were detected at this study area
during the supplemental sampling. The primary migration pathways of munitions and metals
detected in soil are fugitive dust or particulate emission, contact and ingestion. In addition,
the potential exists for chemicals in soil to migrate via surface runoff during periods of heavy
rainfall. The potential for contaminants to reach groundwater from this area is high due to the
creation of a pond following recent remedial actions, however, contaminant concentrations in the
soil are low, minimizing the actual threat.

5.3 Small Arms Ballistics Range (Study Area 13)

This study area is approximately 3.7 acres, located centrally at the northern boundary of Area
A. This area was covered by gravel during the operational period and was used as a test range
for small arms ballistics. A ballistics laboratory for powder blending and bullet loading was
adjacent to this area during the operational period. Lead-contaminated soils and timbers were
removed in an interim action (1986 to 1987). Currently, no buildings exist on this site.

Groundwater and soil samples have been collected from this area to verify the effectiveness of
the completed remedial actions. The supplemental sampling results indicated the presence of
metals in the groundwater and metals and PAHs in the soil. The primary migration pathways of
PAHs and metals detected in soil are fugitive dust or particulate emission as well as contact
and ingestion. In addition, the potential exists for chemicals in soil to migrate via surface
runoff during periods of heavy rainfall. The amount of PAH contamination reaching groundwater
from this area is expected to be low because of the low concentrations detected in the soils and
the immobile nature of the compounds.

5.4 Cannon Range (Study Area 14)

This study area, used for cannon test firing, is approximately 13 acres located at the northeast
corner of the northern boundary of Area A. Since operations ceased at ALAAP, all buildings have
been removed and the remaining area has not been maintained.

Soil samples were collected from this area during the supplemental investigation. Metals,
phthalates and a single munitions hit were detected at this study area. The primary migration
pathways of contaminants detected in soil are fugitive dust or particulate emission, contact,
and ingestion.

5.5 Old Well (Study Area 15)

The Old Well was a relict hand-dug well, located in the northeast portion of Area A, which
served a farm or residence prior to construction of ALAAP and was reportedly approximately 30 ft
deep and 5 ft in diameter. During the razing of the laboratory building that supported the
explosives manufacturing operations, laboratory reagents, non-sparking paints, 55-gallon (gal)
drums of a tar-like material, fire retardant paint, containers of other unidentifiable
materials, and old tires were reportedly disposed of in this well.

Soil and groundwater samples were collected from this study area. Soil and groundwater samples
contained metals and the phthalates. The well and surrounding soils were removed during an
interim removal action in 1986 to 1987. No follow-up sampling was required during the
supplemental investigation due to the complete removal of the structure and surrounding soils.

5.6 Propellant Shipping Area (Study Area 17)

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The propellant shipping houses are located in the south-central portion of ALAAP. The
shipping house area (Series 229 Buildings) used to store propellant prior to shipment and
consisted of 48 buildings, 13 of which are located on the land previously sold to Kimberly
Clark. The remaining 35 buildings, located within the current ALAAP boundary, comprise
Study Area 17 and are split between Area A and Area B.

The shipping houses (except for the foundations) and contaminated soil were removed during a
removal action completed in 1986 to, 1987. Supplemental sampling was completed in this area to
verify the effectiveness of the completed remedial action. Metals and a single nitroaromatic hit
were detected in this study area. The primary release mechanism for lead at this site would be
through release to the atmosphere as particulate or dust emissions, contact, and ingestion.

5.7 New Trench Area (Study Area 30)

During remedial activities conducted by Roy F. Weston, Inc. (Weston) in 1986 to 1987, Study Area
30 was identified. This area is approximately 2.9 acres located north of Study Area 11. Area 30
was used for disposing of eguipment and other general wastes. Contaminated soil was removed at
the time of discovery.

Nitroaromatic compounds were detected in 3 of the 34 soil samples collected during the
Supplemental Investigation. All three samples, which were collected from the 0- to 3-ft depth,
contained 246-TNT, with one sample containing a high concentration [13,900 parts per million
(ppm)] of this compound. Although the concentration of 246-TNT in the second sample was an order
of magnitude lower (1,400 ppm), the results suggested the presence of an area of high
nitroaromatic contamination. Of the three samples that contained 246-TNT, two also contained
135-TNB. The presence of these contaminants is due to past disposal practices in the area. This
area was the subject of an interim removal action to address the nitroaromatics. Supplemental
sampling was completed following the removal action to verify that the actions completed were
effective.

Metals were detected in the soils following the removal action. The primary migration pathways
of the organics and metals detected in soil are fugitive dust or particulate emission, contact,
and ingestion. In addition, the potential exists for chemicals in soil to migrate via surface
runoff during periods of heavy rainfall. The important fate and transport processes of the
metals in the terrestrial environment are adsorption/desorption, precipitation/dissolution, and
speciation. The rate and extent of these processes are influenced by pH, ionic strength,
inorganic and organic ligands, and redox conditions,

5.8 Disposal Area (Study Area 31)

During removal activities conducted by Weston in 1986 to 1987, Study Area 31 was identified.
This area comprises less than 1 acre and is located north of Study Area 11 and east of Study
Areas 30 and 12. Study Area 31 was used for disposing of eguipment and other general wastes.
Remediation of the area was completed following discovery. Supplemental sampling was completed
to verify the effectiveness of the remedial actions.

No nitroaromatic contamination was detected in any of the soil samples collected as part of
the supplemental investigation. Only metals were detected at this study area. The important
fate and transport processes of the metals in the terrestrial environment are adsorption/
desorption, precipitation/dissolution, and speciation. The rate and extent of these processes
are influenced by pH, ionic strength, inorganic and organic ligands, and redox conditions.

5.9 Rubble Pile (Study Area 29) and Number 2 Rubble Pile (Study Area 32)

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During removal activities conducted by Weston in 1986 to 1987, Study Areas 29 and 32 were
identified. These tracts were suspected to have been localized areas used for the disposal of
equipment and other general wastes. Study Area 29 is located near the Area A northwest boundary,
and Study Area 32 is directly across the road. Contaminated soil was removed from both areas
following discovery. Supplemental sampling was completed to verify the effectiveness of the
removal actions.

Soil and groundwater samples were collected from this study area. Metals were detected in the
soil and groundwater and a single nitroaromatic hit was detected in a groundwater sample. This
compound was not detected during a follow-up sampling.

5.10 Henningsburg Area (Area 33)

During removal activities conducted by Weston in 1986 to 1987, Study Areas 33 was identified.
This area was suspected to have been a localized area used for the disposal of equipment and
other general wastes. Contaminated soil was removed shortly after discovery. Study Area 33 is
located centrally near the Area A east boundary.

Supplemental sampling was completed to verify the effectiveness of the removal actions. Metals
and minor concentrations of volatile compounds were detected.

5.11 229 Area (Study Area 34)

During removal activities conducted by Weston in 1986 to 1987, Study Area 34 was identified.
This area was used for disposing of equipment and other general wastes and is located directly
south of Study Area 17. Contaminated soil was removed following discovery. Supplemental sampling
was completed to verify the effectiveness of the removal action.

Soil and groundwater samples were collected from this area during the supplemental
investigation. Metals were detected in both media. The primary release mechanism for the metals
at this site would be through the atmosphere as particulate or dust emissions, contact, and
ingestion.

6.0 Summary of Site Risks

6.1 Introduction

In 1991 through 1995, a supplemental RI was conducted at the request of EPA Region IV to verify
the effectiveness of the completed interim response actions in Area A. A baseline risk
assessment (RA) was conducted as part of the RI to determine if chemicals detected in unposed
soil and groundwater pose a significant risk to human health and the environment. The
supplemental RI and baseline RA determined that soils at two study areas within Area A (Study
Areas 13 and 14) continue to contain lead and explosives at unacceptable concentration and,
therefore, require further remediation.

All media in all Study Areas were sampled after interim response actions were completed. These
data were used to develop the RA for the site. Risks due to site contamination were estimated
for current and future risks to verify that the remedial actions completed to date were
effective. Feasibility efforts were focused on the remaining site contamination that was not
addressed by the earlier remediation efforts. Identified areas with excessive contamination were
Study Areas 13 and 14. Risks identified are presented in the summary section (Section 6.2). The
methods implemented to estimate the risks are in accordance with the risk assessment guidance
for CERCLA sites and are summarized in Sections 6.3 through 6.7. The reader is urged to review
the complete RA for a detailed understanding of the remedial assessment process as it applies to

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this site.

6.2 Health Risks

The methods used in assessing the risks associated with reasonable maximum exposure (RME) to the
site contaminants are those presented in EPA's Risk Assessment Guidance for Superfund (RAGS),
Human Health Evaluation Manual (1989a); RAGS Supplemental Guidance, Standard Default Exposure
Factors (1991); and other EPA guidance. According to RAGS, actions at Superfund sites should be
based on an estimate of the RME expected to occur under both current and future land-use
conditions. The RME is defined in RAGS as "the highest exposure that is reasonably expected to
occur at a site." The intent of the RME is to estimate a conservative exposure case (i.e., well
above the average case) (EPA, 1989a).

Based on RAGS, RME human health risks were determined for each exposure pathway at each study
area and receptor location (Sec. 6.2.5) based on RME concentrations and factors [Sec. 3.0 and
App. C of the RA (ESE, 1995)]. Because of the uncertainty associated with any estimate of
exposure concentration, the upper confidence limit [i.e., the 95 percent upper confidence limit
(MCL 95)] on the mean is the preferred exposure concentration to use in determining potential
health risks. However, according to RAGS, if there is great variability in measured or modeled
concentration values, the MCL 95 may be high, and could exceed the maximum detected value. In
this case, the maximum detected or modeled concentration was used as the exposure concentration.
Exposure factor values (i.e., contact rate, body weight, averaging time, exposure duration) used
in calculating chemical intakes were the 95th percentile values when available; otherwise, the
90th percentile was used. A majority of the exposure factors were provided in RAGs while several
were site-specific factors obtained from site information (e.g., climactic conditions conducive
to dermal exposure).

The health risks were evaluated separately for carcinogenic and noncarcinogenic effects, with
potential carcinogens evaluated for their carcinogenic and noncarcinogenic effects, where a
specific carcinogen has published noncarcinogen criteria.

Risk estimates relevant to aquifer uses are presented for hypothetical future unposed exposure
pathways. Worker exposure to contaminated groundwater exceeding MCLs was not evaluated under the
current use exposure scenario since these individuals are not currently using groundwater. Risk
estimates relevant to direct contact and incidental ingestion of surface soil and dust are
presented for both current and hypothetical future onsite exposure scenarios. Current unposed
risks are evaluated based on a worker and recreational hunter exposure scenario, while the
future unposed risks are evaluated based on a hypothetical future residential exposure scenario.
The RA was conducted in five sequential steps, each of which are summarized below.

Ecological risks, risks to aquatic and terrestrial wildlife, were also evaluated. Ecological
risks were assessed for aquatic receptors (e.g., fish and invertebrates) and terrestrial
receptors (e.g., plants and animals).

6.2.1 Media of Concern

The risk assessment process outlined in the RA (ESE, 1996) involves a consideration of chemicals
of potential concern (COPCs) for each medium (e.g., soil, groundwater, surface water, and
sediment) and routes of current and future exposure for human and nonhuman populations.

6.2.2 COPCs

During the initial steps of the RA, COPCs for human and nonhuman receptors were developed based
on the information contained in the Supplemental RI (ESE, 1996). COPCs are those chemicals

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detected at the site that may pose health concerns to human health and/or environment, and are
included for further quantitative risk evaluation. COPCs were selected based on a detailed
evaluation of the analytical and historical data according to procedures outlined in EPA's risk
assessment guidance  (EPA, 1989a) which selects COPCs based on potential toxicity to humans and
wildlife and discounts chemicals that are associated with the natural concentrations of metals
and inorganics present in site-specific background soil. The data considered in the RA were
taken from several ESE sampling events (1979 to 1995) to include supplemental sampling that
occurred as part of the interim response actions at areas where removal actions occurred. COPCs
were developed and evaluated separately for all environmental media. The final list of COPCs for
the ALAAP RA include the following:
    Volatile Organic Compounds
    Acetone
    Methyl butyl ketone
    1,1,2,2,-Tetrachloroethane
(VOCs)
     Bromomethane
     Methyl isobutyl  ketone
     Trichloroethene
    Semivolatile Organic Compounds  (SVOCs)
    Miscellaneous
    Bis(2-ethylhexyl)phthalate
    Di-n-butyl phthalate
     Carbazole
     Diethyl  phthalate
    Polycyclic Aromatic Hydrocarbons  (PAHs)
    Acenaphthene                    Acenaphthylene
    Benz(a)anthracene               Benzo(a)pyrene
    Benzo(k)fluoranthene            Chrysene
    Benzo(ghi)perylene              Indeno(1,2,3-cd)pyrene
    Fluorene                        Pyrene
    Benzo(b)naphtho
     (1,2-D)thiophene
    Munitions/Nitroaromatic Chemicals
    1,3-Dinitrobenzene
    N-Nitrosodiphenylamine

    Inorganic Chemicals
    Aluminum
    Beryllium
    Cobalt
    Lead
    Nickel
     2,4-Dinitrotoluene
     1,3,5-Trinitrobenzene
Arsenic
Cadmium
Copper
Manganese
Vanadium
Barium
Chromium
Iron
Mercury
Thallium
  Chloroform
  Methylene Chloride
  Trichlorofluoromethane
  Dibenzofuran
  1,2,4-Trichlorobenzene
                                Anthracene
                                Benzo(b)fluoranthene
                                Fluoranthene
                                Naphthalene
                                Phenanthrene
 2,6-Dinitrotoluene
2,4,6-Trinitrotoluene
Table 2 provides a summary of COPCs detected in each medium at each study area at the site.

6.2.3 Exposure Assessment
Exposure is defined as the contact of an organism with a chemical or a physical agent. The
exposure assessment is the determination or estimation of the magnitude, frequency, duration,
and route of exposure. An exposure assessment provides a systematic analysis of the potential
mechanism by which a receptor may be exposed to chemical or physical agents at or originating
from a site. The objectives of an exposure assessment are to:

       •      Define exposure pathways;
       •      Identify potentially exposed population(s);  and
       •      Measure or estimate the magnitude,  duration,  and frequency of exposure for each

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receptor (or receptor group).

Factors influencing contaminant migration are also considered during an exposure pathway
assessment.

6.2.3.1 Potentially Exposed Human Populations

Currently, operations at the site are completely inactive, no military activity is ongoing.
Under future projected land use conditions, the current owner (Woodlander, Inc.) plans to use
the site for hunting purposes. The types of activities expected include wildlife management for
future hunting purposes by planting grass for deer and building bird feeding areas. These
activities will be carried out by a wildlife biologist employed by the current owner. No
residential communities exist nor are planned at the boundary or downgradient of Area A.

The 1986 RI report (ESE, 1986) contains information regarding the residential areas, municipal
water service, and water sources near [within 1.6 to 3.2 kilometers (km)] ALAAP. County tax
records indicate that the density of residences is low near ALAAP. A total of 140 residences or
structures was identified within an area of approximately 47 sguare kilometers (km) adjacent to
ALAAP boundaries. Housing density ranged from 0 to 57 residences per section (2.6 km 2). Most
residences were concentrated in the communities of Kymulga, southeast of ALAAP, and Laniers,
north of the site.

6.2.3.2 Current Land Use

Portions of ALAAP are developed to be released as excess property, which reguires certification
that the released property is free of contamination and may be released for unrestricted land
use. Parcels of the site have already been approved for property transaction, upon confirmation
of the absence of contamination. Area A is one such parcel having been auctioned to private
owners. No restrictions were placed on the deed and the Army retains responsibility for all
cleanup operations resulting from past Army use of the property.

The future land use, as currently stated by the landowner (Woodlander, Inc.), will be primarily
recreational hunting. However, the remedial project manager (RPM) indicated that, at one time, a
chemical manufacturing firm had negotiated to rent Study Area 11 for special chemical storage
purposes. A similar future use is possible for this study area. Chemical exposure under this
type of use will be primarily to the worker. No plans exist for the site to be used for
residential purposes in the near future. However, due to the unrestricted land use designation
on the property, a conservative approach to risk estimation is taken by considering future
residential exposure to children and adults.

6.2.3.3 Human Subpopulations of Potential Concern

Currently, no identifiable human population of potential concern exists at Area A. Under the
future land use conditions, the property and wildlife maintenance workers and hunters visiting
the area are the potential receptors of concern. No residential receptors are currently in the
area, nor are they likely in the foreseeable future. However, since unrestricted land use is
permitted, a projected residential exposure is considered in the RA to represent a worst-case
exposure and impact scenario. Currently, no sensitive human subpopulation lives within the area,
but risks to a child in a residential exposure scenario are evaluated to cover worst-case
conditions. The human exposure pathways used in the RA follow methods outlined by EPA (1989a).

6.2.3.4 Potentially Exposed Wildlife

Because of the degree and type of management within Area A, the availability of well-developed,

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distinct communities is low. Therefore, many of the resources across the site are fairly uniform
and do not represent distinct habitat types that support unique wildlife populations. Much of
the region surrounding ALAAP is managed for forest resources at a level exceeding the management
observed at ALAAP. Practices such as controlled burning to reduce understory and groundcover
vegetation have been absent in recent decades at ALAAP. This has allowed the growth of dense
thickets of briars, blackberry, honeysuckle, and other herbaceous vegetation favoring wildlife
species such as gray catbird (Dumetella carolinensis), northern mockingbird (Mimus polyglottos),
Carolina wren (Thryothorus ludovicianus), and rufous-sided towhee (Pipilo erythropthalmus).

Although much of Area A is uniform in wildlife resources, significant differences are apparent
when comparing the wooded and logged areas with areas that have received recent remedial
activity. The wooded and logged areas continue to support vegetation associated with pine and
mixed pine hardwood communities. The areas that have been remediated, however, represent earlier
successional systems ranging from bare soil to old field vegetation with no canopy cover, little
shrub cover, and sparse to moderate herbaceous cover.

Most of the avian species observed across the site are permanent residents. However, others like
the acadian flycatcher (Empidonax virescens), blue-gray gnatcatcher (Polioptila caerulea),
chimney swift (Chaetura pelagica), eastern kingbird (Tyrannus), summer tanager (Piranga rubra),
and swallow are summer breeding species that had not yet migrated south during the late Septem-
ber bird survey. Several more breeding birds can be expected to use site resources during the
spring and summer seasons.

The only wintering nonresident birds observed were the northern harrier (Circus cyaneus) and
house wren (Troglodytes). Several more winter residents can be expected to be present for
portions of the fall and winter. The oak-dominated swamp in Study Area 11 is known to support
several wood ducks (Aix sponsa) during late fall and early winter.

Although some standing water is intermittently present at some study areas in Area A, no
significant permanent aguatic resources are supported within known areas of contamination.
Although the hardwood swamp within Study Area 11 represents a sensitive habitat, the swamp is
removed from the igloo area where localized soil contamination was observed in the 1980 samples.
Surface water runoff may carry small quantities of contaminants toward the swamp, but the
watershed is large relative to the known areas of contamination. Therefore, concentrations of
contaminants would be expected to be low in the wetland.

6.2.3.5 Representative Wildlife Receptors

Due to the number and diversity of nonhuman receptors at a site, it is not feasible to evaluate
each species present. EPA guidance indicates that biological receptors (ecosystem components
expected to reflect adverse effects of pollutant stress) and endpoints (type of actual or
potential impact due to contaminant exposure by a receptor) be selected to represent indicators
of any potential adverse effects to all ecosystem components (EPA, 1988). Initial screening was
done to identify receptors present at the site. EPA guidance also indicates that consideration
be given to rare, threatened, and endangered species, and to species of commercial or sport
value (EPA, 1989a). Sensitive populations or subpopulations that could be more adversely
affected by the contaminants of concern, such as juveniles and species with predicted
higher-than-average exposure rates, should also be considered.

A survey was completed as part of the RI process (ESE, 1990) to determine if threatened or
endangered species were present onsite. Particular emphasis was placed on assessing red-cockaded
woodpecker resources. It was determined at that time that red-cockaded woodpeckers do not reside
at the ALAAP property nor are they likely to forage there. The only other listed wildlife
species likely to occur at the site is the bald eagle, which might overwinter along the river,

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but is not likely to forage in Area A. Inventories were conducted during the spring flowering
period to determine if federally listed plant species occurred onsite (ESE, 1990).  None of the
listed species was located and little habitat that could support these species was identified
onsite. As a result of these survey efforts, it has been assumed for the purposes of the RA that
threatened or endangered species do not occur onsite and do not reguire further evaluation.

Species were selected as indicator organisms at the different study areas based on the results
of field investigations and the likelihood of each species being distributed in the habitat at
each study area. Indicator organisms selected for each study area include:

    Study Area 11    Peromyscus mice, Raccoon, Whitetail Deer, Blackberry, Daphnia,
                     Scenedesmus, Chironomis
    Study Area 12    Peromyscus mice, Bobwhite, Whitetail Deer, Blackberry
    Study Area 13    Whitetail Deer, Slender Bush Clover, Daphnia, Scenedesmus, Chironomis
    Study Area 14    Whitetail Deer, Slender Bush Clover
    Study Area 17    Whitetail Deer, Blackberry
    Study Area 29    Whitetail Deer, Blackberry
    Study Area 30    Peromyscus mice, Bobwhite, Whitetail Deer, Blackberry
    Study Area 31    Peromyscus mice, Whitetail Deer, Blackberry
    Study Area 32    Whitetail Deer, Slender Bush Clover
    Study Area 33    Peromyscus mice, Raccoon, Whitetail Deer, Blackberry
    Study Area 34    Whitetail Deer, Blackberry

6.2.3.6 Identification of Exposure Pathways

An exposure pathway describes the course a chemical or physical agent takes from the source to
the exposed receptor. An exposure pathway analysis links the sources, locations, and types of
releases with population locations and physical activity patterns to determine the significant
human and nonhuman exposure pathways.

For an exposure pathway to be complete, the following four components are essential:

       •      A source or a release from a source,
       •      A probable environmental migration pathway (e.g.,  leaching,  volatilization,  or
              partitioning from one medium to another)  of a site-related chemical or physical
              agent,
       •      An exposure point where receptors may come in contact with a site-related chemical
              or physical agents,  and
       •      A route by which potential receptors  may be exposed to a site-related chemical or
              physical agent (i.e.,  inhalation,  direct dermal contact,  or incidental ingestion).

If any of the four components are missing, the exposure pathway is incomplete and does not
suggest exposure from the site.

As reguired by EPA Superfund guidance, the exposure pathways for Area A were analyzed based
on current and future unrestricted use of the site.

6.2.3.7 Identification of Potential Human Exposure Pathways by Study Area

Exposure scenarios at each study area were identified based on the type of activities carried
out in the area. Each area was evaluated separately to identify the potential exposure and the
areas of contamination needing remediation. Significant complete exposure pathways were selected
based on the type of contamination onsite and the environmental medium contaminated, as well as
the activities of the hypothetical human population at the site.

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The human exposure scenarios evaluated in the RA include

Current Hunter Ingestion, dermal, and inhalation exposure to
surface soil.

Current Residential Ingestion of venison from deer harvested unposed.

Future Residential Ingestion, dermal, and inhalation (dust and
vapors) exposure to surface soil, groundwater,
surface water, and sediment.
Future Worker Ingestion, dermal, and inhalation exposure to
surface soil and groundwater.

6.2.3.8 Identification of Potential Ecological Exposure Pathways

Animals may be present in or on the soil and, depending on their physiological capabilities and
behavior, may migrate or burrow between various contaminated soil, layers. They may also migrate
between various contaminated areas. In Area A, limited contact with surface water may provide an
exposure pathway to terrestrial organisms. Terrestrial animals would likely be exposed on an
intermittent basis due to the limited extent of the water and its ephemeral nature. Exposure to
soil can occur through ingestion, dermal contact, inhalation of dust, and ingestion of food
living/growing in soil. Terrestrial plants can be exposed to contaminants in soil via root
exposure or deposition of contaminated dust onto leaves.

Aguatic species inhabiting surface water would be exposed via uptake across cellular membranes
(algae) and digestive and/or gill surfaces (invertebrates).

Sediments, particularly fine-grained sediments in depositional environments, often act as a sink
for contaminants. These bottom sediments may provide an exposure pathway to terrestrial animals
in Area A, especially since these are generally exposed (e.g., not covered by water). Benthic-
dwelling organisms would have constant exposure. Potential exposure pathways via bottom
sediments may include ingestion/dermal intake of contaminated sediments or consumption of
contaminated prey or food items.

6.2.3.9 Quantification of Exposure

Quantifying the magnitude of exposure and assessing the freguency and duration of exposure to
the population involves two stages: exposure point concentration estimation and pathway-specific
intake estimation.

Exposure point concentrations are the contaminant concentrations that a receptor may come in
contact with at a site. The monitoring data for Area A were collected over a period of time and
illustrate the potential environmental migration and degradation of the chemicals. The site was
operational during the 1940s, and essentially no manufacturing-related activity has occurred
since 1945. Most of the sampling was done in 1989, 1991, 1994, and 1995, and the exposure
concentrations were calculated using the site monitoring data. Exposure point concentrations
were calculated following the statistical methods described in the Baseline Risk Assessment
(ESE, 1995).

Pathway-specific intake is an estimation of how much chemical enters a receptors body and is a
function of exposure freguency, duration and receptor-specific factors such as inhalation rates,
body weight, skin surface area, etc. The exposure factors used in calculating intakes are
presented in Appendix C and Section 3.0 of the RA.

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6.2.4 Toxicity Assessment

The objective of the toxicity assessment is to characterize the nature of the health effects to
human and wildlife receptors associated with the COPCs identified at ALAAP. The characterization
includes a qualitative evaluation of the available pharmacokinetic and health effects data and a
quantitative evaluation of the available dose-response information to provide values for
estimatinq acceptable intake levels and quantifyinq risks.

6.2.4.1 Human Toxicity Assessment

Cancer slope factors (CSFs) have been developed by EPA's Carcinoqenic Assessment Group for
estimatinq lifetime cancer risks associated with exposure to potentially carcinoqenic chemicals.
CSFs, which are expressed in units of milliqrams per kiloqram per day (mq/kq-day) -1, are
multiplied by the estimated intake of a potential carcinoqen, in mq/kq-day, to provide an upper-
bound estimate of the excess lifetime cancer risk associated with exposure at that intake level.
The term "upper-bound" reflects the conservative estimate of the risks calculated from the CSF.
Use of this approach makes underestimation of the actual cancer risk hiqhly unlikely. CSFs are
derived from the results of human epidemioloqical studies or chronic animal bioassays to which
animal-to-human extrapolation and uncertainty factors have been applied.

Reference doses (RfDs) have been developed by EPA for indicatinq the potential for adverse
health effects from exposure to chemicals exhibitinq noncarcinoqenic effects. RfDs, which are
expressed in units of mq/kq-day, are estimates of lifetime daily exposure levels for humans,
includinq sensitive individuals. Estimated intakes of chemicals from environmental media (e.g.,
the amount of a chemical inqested from contaminated drinkinq water) can be compared to the
RfD. RfDs are derived from human epidemioloqical studies or animal studies to which uncertainty
factors have been applied (e.g., to account for the use of animal data to predict effects on
humans). These uncertainty factors help ensure that the RfDs will not underestimate the
potential for adverse noncarcinoqenic effects to occur.

Tables 3 and 4 provide a summary of the available noncarcinoqenic and carcinoqenic chronic
dose-response information for both the oral and inhalation exposure routes for each chemical of
concern (COG). When insufficient data are available to determine dose-response values for human
risk characterization, health-based values are developed usinq the available requlatory
references and resources for human health dose-response values.

6.2.4.2 Chemicals Havinq No EPA Human Toxicity Values

Noncarcinoqenic effects were evaluated for all of the COPCs identified at Area A, includinq
potentially carcinoqenic chemicals. EPA has developed toxicity values for most, but not all, of
the compounds identified at Area A.

An RfD has not been developed for any of the potentially carcinoqenic PAHs. For comparative
purposes, the oral RfD for the PAH pyrene (0.03 mq/kq/day) was used to evaluate potential
noncarcinoqenic hazards associated with exposure to the carcinoqenic PAHs detected at the site.
This surroqate approach is outlined in EPA Reqion IV quidance (EPA, 1995).

With respect to the inorqanic COPCs, no RfDs, are available for metallic thallium. The oral RfD
for thallium chloride (the most toxic thallium salt) is used to evaluate this metal. Also, no
RfDs are available for the heavy metal lead. Due to the hiqh toxicity of lead in children, EPA
recommends usinq the Inteqrated Exposure Uptake Biokinetic (IEUBK) Model (EPA, 1994b) on a
site-by-site basis to evaluate blood-lead (PbB) levels instead of the RfD approach. In addition,
a soil screeninq level of 400 mq/kq (EPA, 1994a) is available to evaluate soil lead and an

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action level of 15 Ig/L is available to screen lead in groundwater (EPA, 1994b).

The macro- and micro-nutrients calcium, magnesium, potassium, sodium, zinc, and iron were
regularly selected as COPCs at many of the study areas because their soil concentrations
exceeded background soil concentrations and no RfDs or CSFs were available to evaluate them
further in the screening process. These inorganics are reguired for normal cellular function in
mammals and for skeletal integrity. To determine if soil concentrations of calcium; magnesium,
sodium, iron, zinc, and potassium present at the site are sufficient to provide reguired
guantities of these chemicals, daily intakes (from soil ingestion) were compared to the U.S.
Department of Agriculture's (USDA's) recommended daily allowance (RDA). The ratio of daily
intake to the RDA is less than 10 for adults and children at each study area where calcium,
magnesium, sodium, zinc, or potassium were identified as COPCs. This means that soil ingestion
alone will not supply these people with enough calcium, magnesium, or potassium to meet their
daily reguirements. It can be assumed from this analysis that the concentrations of these
macronutrients in the soils are at insufficient levels to be toxic to humans. Therefore, they
were not considered further in the BRA. Iron did exceed 10 times the nutritionally essential
levels at some study areas, and was therefore retained for further analysis.

Of the inorganic COPCs at Area A, lead is currently classified as a Group B2 suspect human
carcinogen. However, no CSF values are available for this metal, and the potential
carcinogenicity associated with exposure to this metal cannot be evaluated. Only the potential
noncarcinogenic hazards associated with exposure to lead were evaluated.

6.2.4.3 Evaluating Toxicity to Ecological Receptors

Risks to ecological receptors are guantitatively evaluated by comparing the chemical intake (for
terrestrial receptors) or exposure concentration (for aguatic receptors) to a toxicity reference
value (TRV) for that chemical in the specific receptor. TRVs ecotoxicity data for terrestrial
and aguatic organisms are discussed in the toxicity profiles for the major COPCs in Appendix E
of the RA (ESE, 1995). Ecotoxicity benchmark values were chosen from the scientific literature
for each COPC for comparison with estimated site exposures. Selected benchmarks for the COPCs at
Area A were obtained from the available literature and were chosen based on the following
considerations:

• Including acute and chronic effects,
• Choosing results of tests using organisms as closely related taxonomically to
representative receptors as possible,
• Choosing tests with ecologically relevant endpoints, and
• Choosing tests conducted with an ecologically relevant exposure pathway.

The preferred value that was sought was a chronic no-observed-adverse-effect level (NOAEL). This
NOAEL value was then adjusted for extrapolation of toxicity data between species. When no NOAEL
value was available for a chemical in the literature, other values such as lethal doses for 50
percent of an exposed group (LD 50 S) were used to derive a TRV. The toxicity data were adjusted
to account for extrapolation uncertainties according to guidance provided by the U.S. Army
(USAERDEC, 1994). The TRVs used in the RA of wildlife are presented in the RA (Tables 4.4-1
through 4.4-5).

TRVs are derived from raw ecological benchmarks using the following eguation:

6.2.5 Risk Characterization

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The objective of the risk characterization is to assess current and future risks to human health
and the environment from site contamination by integrating the information derived in the
exposure and toxicity assessments (Sections 3.0 and 4.0). The methods used for risk calculations
are those outlined by EPA regionwide, EPA Region IV guidance, and other relevant guidance [Oak
Ridge National Laboratory (ORNL), 1986] pertaining to human and ecological risk
characterization.

6.2.5.1 Site-Specific Human Risk Characterization

The carcinogenic risks and His were calculated for all Study Areas. Because the activities
performed at each of the study areas differ and the areas are not in close proximity to each
other, the risks were presented separately for each area. Characterizing each study area
separately allows for prioritization of remedial activities that may be reguired.

The potential site risks were compared to EPA's risk range of 1 in 1,000,000 to 1 in 10,000 (10
-6 to 10 -4), this range is generally considered to be represent as the acceptable health risk
range [40 Code of Federal Regulations (CFR) 300, 430:62]. EPA uses the 10 -6 to 10 -4 risk range
as a "target range" within which EPA strives to manage risk as part of Superfund cleanup.
Therefore, the risk results for this study are summarized to highlight those individual
chemicals and media that exceed the lower bound of the risk range, 10 -6 . The 10 -6 risk level
serves as a starting point, or point-of-departure to provide focus on those chemicals that may
reguire further evaluation as part of subseguent studies (i.e., feasibility studies) if the
cumulative site risk exceeds 10 -4. When a cumulative carcinogenic risk to an individual under
the assumed exposure conditions at the site exceeds 1 in 10,000 (10 -4), CERCLA generally
reguires remedial action at the site (EPA, 1991).

If the cumulative risk is less than 10 -4, action generally is not reguired but may be warranted
if a risk-based chemical-specific standard [e.g., maximum contaminant level (MCL)] is violated,
a HI exceeds 1, ecological impacts are posed, or a risk manager indicates that a lower risk
level must be achieved due to site-specific reasons.

Table 5 presents a summary of the human exposure pathways and chemicals that contribute to a
total risk of 1 x 10 -6, and an HI > 1. As noted, none of the current exposure pathways exceeded
carcinogenic or noncarcinogenic target risk levels. The chemical specific HI and risk results
for all COPCs and all exposure scenarios are presented in App. G of the RA (ESE, 1995).

Only two study areas, Study Areas 13 an 14, presented unacceptable human health risks which
are to be addressed in the recommended remedial actions. A description of the risk associated
with these sites is presented in the following paragraphs.

Study Area 13

Hunter and Current Resident - The cumulative His for the adult hunter exposed to site soils and
the current resident exposed to affected venison caught by the hunter are below the target HI of
1, indicating that this area does not pose adverse human health effects to a hunter or current
resident based on the exposure information evaluated.

The cumulative risks for the hunter and current resident exposure scenarios, 7E-06 and 6E-07,
respectively, are within or below EPA's acceptable risk range based on the exposure information
evaluated.

Future Resident and Worker-Future adult and child residents have a potential for adverse health
effects predominantly as a result of exposure to manganese in groundwater [approximately 83
percent contribution to the hazard index (HI)] (Apps. D and G). The cumulative His for a future

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residential and adult are 66 and 120, respectively, and the future worker HI is 24. Lesser
contributors to the HI include cadmium, aluminum, chromium, barium, and vanadium for adult and
child residents and nickel and cobalt for child residents. Future workers have a potential for
adverse health effects largely (around 83 percent of HI) as a result of exposure to manganese in
groundwater. Other chemicals that contributed to the HI to a smaller extent are cadmium,
aluminum, and chromium. The exposure concentration for lead in the groundwater at Study Area 13
is 748 Ig/L, which exceeds EPA's action level of 15 Ig/L.

The cumulative risk for the future residential exposure scenario of 2E-04 exceeds EPA's
upperbound of the acceptable risk range. This risk is explained primarily by exposure to
benzo(a)pyrene in soil, which contributed approximately 71 percent to the risk (Apps. D and G).
Chemicals contributing to a lesser extent to the soil risk are benzo(b)fluoranthene,
benz(a)anthracene, indeno(1,2,3-cd)pyrene, beryllium, and benzo(k)fluoranthene. The cumulative
risk for the future worker exposure scenario of 3E-05 is within EPA's acceptable risk range
based on the exposure information evaluated.

Chemicals contributing to a majority of the risk in groundwater include manganese, aluminum,
cadmium, chromium, lead, and barium. The elevated metals concentrations were detected in well
P-86, which was installed in spring 1995 and has only been sampled once. This well is
approximately 1,200 ft from the operational boundary of the study area in the undeveloped
portion of the site and is completed into soils contained in the Chewlacla soils group.
Manganese, aluminum, chromium, lead, and barium were detected in every surficial soil sample
collected from this soil group and in every sample collected with depth (except barium and
chromium, which were BDL in two samples), including samples collected at 50 ft-bgs (in the soil
boring for well P-86). As such, it is inferred that the concentrations detected in the
unfiltered samples are a result of sample turbidity, reflecting the local soil group, which has
been shown to contain these metals.

The single hit of cadmium was detected only in the unfiltered sample. Although this compound
was not detected as freguently in the soil, its occurrence is still assumed to be related to the
silty nature of the water sample from a well that has been purged and sampled only once.

To continue to assess the relationship between groundwater sample turbidity and metals content,
a decision was made to conduct a low flow purge/sampling of selected wells within Area A. ADEM
developed a list of wells where groundwater concentrations of certain metals (lead, beryllium,
cadmium, chromium, and manganese) had exceeded Alabama maximum contaminant levels (MCLs) or
health based action levels during recent sampling events. The wells selected were P-75 (Study
Area 11), P-80 (A-B Divide), P-82 (Study Area 34), P-86 (Study Area 13), P-88 (Study Area 121)
and P-89 (Study Area 13).

Low flow purging involved setting a small submersible pump to the screen depth in the well. The
well would then be pumped at a low pumping rate [typically 0.5 to 1 gallon per minute (gpm)].
Discharge water was monitored at 5-minute intervals for pH, conductivity, and temperature to
determine when water was being produced directly from the aguifer. Purging continued until the
measured parameters were within 5 percent of preceding readings for 3 monitoring periods. As
the pump was made of stainless steel and Teflon (R), a groundwater sample could be collected
from the pump discharge at the end of the purge cycle. The advantage to this method is that
sediments within the well and those within the sand pack were not disturbed during purging and
sampling, which in the past had led to a turbid sample. To measure the degree of turbidity
associated with each sample, total suspended solids (TSS) were measured from each sample in the
lab.

Sample analysis showed the expected reduction in the metals concentrations. Cadmium, beryllium,
and lead were not detected in any of the samples collected. Chromium was detected in two of the

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samples at concentrations well below the 100 Ig/L ADEM MCL. Manganese, which is the most soluble
of the metals of concern, was detected in each of the samples at concentrations below any health
action level: A complete presentation of the analytical results from this sampling episode can
be found in the RI addendum.

Study Area 14

The cumulative risks for the hunter and current resident exposure scenarios, 3E-08 and 2E-08,
respectively, are below EPA's acceptable risk range based on the exposure information evaluated.

Future Resident and Worker - The cumulative His for the future resident and worker scenario are
below 1, indicating that these receptors are not expected to have an increased potential for
(noncarcinogenic) adverse health effects as a result of exposure to chemicals in soil at this
study area. However, the exposure concentration for lead in Study Area 14 soil is 13,500
milligrams per kilogram (mg/kg), which exceeds EPA's guidance levels of 400 mg/kg for
residential exposure and 1,000 mg/kg for worker exposure.

The cumulative risks for the future resident and worker exposure scenarios, 1E-06 and 2E-07,
respectively, are within or below EPA's acceptable risk range based on the exposure information
evaluated.

6.2.5.2 Ecological Risk Summary

Methods are still being developed to guantify risks to aguatic and terrestrial ecosystems.
Variability in population dynamics and other parameters is often great even under natural
conditions. However, comparisons of ecotoxicological benchmarks and potential exposure
concentrations can be made to screen for potential problems. Ecologists then evaluate the
results of those comparisons to estimate the potential for adverse effects to the natural
systems. One important difference between ecological and human health evaluations is that the
emphasis is placed on populations, communities, and ecosystems in nonhuman systems (unless the
site evaluation must include one or more rare or endangered species). Therefore, the potential
effects predicted for individuals must then be extrapolated to populations and communities to
evaluate the potential for measurable adverse impacts to the ecosystem.

For the RA, soil exposure point concentrations were converted to daily intakes benchmarks for
terrestrial animals, which were then compared directly to the ecological TRVs. The TRVs for
terrestrial plants were compared directly to MCL 95 or maximum concentrations at each study area
as were benchmarks for aguatic receptors. Concentrations of contaminants in the sediments were
converted to porewater concentrations via standard eguilibrium partitioning methods. Porewater
concentrations were then compared to toxicity information for chironomids, when available, or to
ambient water guality criteria (AWQC) for the protection of freshwater aguatic life or other
appropriate freshwater aguatic life benchmarks when chironomid data were unavailable.

To determine if the potential exists for adverse ecological impacts, potential exposure
concentrations of a chemical are compared to the ecotoxicity benchmarks for that chemical in the
specified medium to produce an ecotoxicity guotient (EQ). Similar to human His, EQs less than
1.0 suggest that the benchmark effect is unlikely to occur in the individual organism. EQs
greater than 1.0 can indicate the potential for adverse impacts to the individual organism and
reguire further evaluation. Although the guotient method does not provide an estimate of

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uncertainty and is not an estimation of risk, it is a commonly used method for screening
ecological effects resulting from exposure to hazardous chemicals (EPA, 1989b).

According to U.S. Army ecological risk assessment guidance (Wentsel et al., 1994), in general,
EQs exceeding 1 indicate a potential risk; however, since EQs merely provide point estimates,
effects probabilities cannot easily be specified. The following interpretation of EQs was
suggested in the Army guidance: chemicals with EQs between 1 and 10 have "some small potential"
for adverse effects, between 10 and 100 have "significant potential" for adverse effects, and
greater than 100 have "expected" adverse effects. This interpretation can be used as a rule of
thumb for evaluating EQs. A summary of the EQs exceeding 1 is presented in Table 6. A summary of
a summary of all EQs for all media can be located in the RA in Tables 5.4-1, 5,4-2, and 5.4-3.

6.2.5.3 Summary of Human and Ecological Risks

As shown in Table 5 and 6, the chemicals contributing to risk more than 1 x 10 -6, His more than
1, and EQs more than 1 are primarily metals. These chemicals that are the primary risk
contributors are referred to as the final COCs. Historical data inicated isolated detections of
munitions in groundwater above risk and HI levels, however, no munition compounds contributed
to His or EQs more than 1. Although, the primary chemicals associated with the manufacture of
munitions are nitroaromatics (e.g., TNT, 24DNT, 26TNT) none of these compounds resulted in
excess health risks. Only one organic compound, benzo(a)pyrene, resulted in excess risks at one
area, Study Area 13 soil. The presence of benzo(a)pyrene is most likely from past controlled
burns in the area. Except for lead, which may be associated with ballistics and cannons, the
inorganic COPCs are distributed across all areas in Area A at similar concentration ranges in
soil and groundwater, indicating that the inorganics are not unigue to the munitions operations
of a particular area. Therefore, with the exception of lead, the inorganics are not site-related
and represent the metals typically identified in natural background soils in the region.

As with soil, the presence of metals/inorganic compounds in gourndwater have been demonstrated
by RI field studies and comparison to site-specific background, to be representative of
concentrations expected in regional groundwater. Therefore, inorganics, with the exception of
lead, were determined not to be site-related.

In summary, the human and ecological RA indicated that the COCs reguiring evaluation in
the FS are lead in soil.

6.2.6 Uncertainty Analysis

The risk measures used in Superfund site RAs are not fully probabilistic estimates of risk but
are conditional estimates given a set of assumptions about exposure and toxicity. It is
important to specify the assumptions and uncertainties inherent in the RA fully to place the
risk estimates in proper perspective (EPA, 1989a). A gualitative analysis of each human and
ecological RA component is often sufficient and is presented in Tables 7 and 8.

7.0 Description of Remedial Alternatives

Two interim response actions were completed at the site prior to the issuance of this document.
The first action, completed in 1986 to 1987 was accomplished without the issuance of an interim
ROD. This action was initiated prior to the site being included on the NPL in July 1987. In
this action, soils considered to be contaminated were excavated from within Area A and
transported to Area B without treatment. These soils subseguently became the Stockpile Soils OU
within Area B of the Installation. A ROD for the Stockpile Soils OU was issued in December 1991
and recommended incineration as the preferred alternative.

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During the initial stages of the supplemental investigations, it was determined that soils in
Study Areas 12 and 30 contained lead and explosives at unacceptable concentrations. An interim
ROD for soils in Study Areas 12 and 30 was submitted in April 1994 which recommended
incineration as the preferred alternative.

Supplemental investigations were completed following the second remedial action. This
investigation included collecting samples from all media within all study areas to determine the
contamination status of the site following the completion of interim response actions. These
investigations determined that soils within Study Areas 13 and 14 contained PAHs and lead at
unacceptable concentrations. The RA completed for the site, based on data collected after the
completion of all interim response actions, determined that all remaining study areas gualified
for No Further Action. The remainder of this section details alternatives presented to complete
the final remedial action.

The following is a brief description of final remedial alternatives developed for Study Areas 13
and 14.

7.1 Study Area 13 Alternatives

7.1.1 No Action (Alternative 13-1)

No action is taken to reduce constituent concentrations in soil media. The no action
alternative is used as a baseline for comparison with the other soil media alternatives. This
alternative was retained for detailed analysis.

7.1.2 In Situ Bioremediation (Alternative 13-2)

Bioremediation is a preferred means of cleanup for soils containing organic pollutants because
it can provide a final solution through complete decomposition of the target compounds to
acceptable residual levels. Bioremediation is often a very cost-effective method for remediation
of various amounts of contaminated soils. The in situ bioremediation alternative uses organic
amendments to increase the ability of the soil matrix to provide water and nutrients to target
compound-degrading microorganisms, and transiently bind pollutants, thereby reducing the acute
toxicity of the soils agueous phase, which allows microorganisms to survive in soils containing
high concentrations of toxicants. The bioremediation process consists of nutrient addition to
the soil matrix, distribution of nutrients throughout the matrix, and monitoring of the active
microbial population until the bioremediation process is complete. This alternative was
retained for detailed analysis.

7.1.3 Excavation, Solvent Extraction, and Disposal (Onsite) (Alternative 13-3)

This alternative uses a specialized solvent system to treat the BAP-contaminated soils. The
solvent is a mixture of polar and nonpolar components that break emulsions of oil, water, and
inorganic constituents. The treatment process consists of three unit operations: pre-treatment,
extraction, and solvent fractionation. The process can extract organics from wastes with
concentrations as high as 40 percent by weight and discharge a relatively nonhazardous stream of
inorganics with less than 0.1 percent organics. Any recovered water containing dissolved
organics in the low parts per million range can be biologically treated prior to disposal. The
organic-phase-containing solvent and the contaminants from the extraction stage are distilled in
a fractionation train. The solvent system is recovered at a temperature of less than 50 degrees
Centigrade and is recycled to the process. The contaminants are collected for further disposal
or reuse. This alternative was not retained for detailed analysis.

7.1.4 Excavation, Thermal Desorption, and disposal (Onsite) (Alternative 13-4)

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This alternative applies thermal technology to treat BAP-contaminated soils. Contaminated soil
is fed into a thermal treatment unit with a front end loader. Large rocks and debris are
initially screened off. Contaminated soil is heated in the primary treatment unit (counter flow
rotary kiln) and process gas temperatures rise. The process gas combines with evaporated soil
mixture and volatilized hydrocarbons. Maximum soil temperatures of 900!F occur prior to soil
discharges into a cooling chamber for rehydration and fugitive dust control. The process gas
stream is filtered in a baghouse and then combusted in the, secondary treatment unit (thermal
oxidizer). Baghouse fines are kept hot and combined with the treated soil. This alternative
was not retained for detailed analysis.

7.1.5 Excavation, Slurry Phase Bioremediation, and Disposal (Onsite) (Alternative 13-5)

This alternative uses a bioslurry reactor, similar to conventional suspended growth processes,
such as activated sludge treatment, to treat BAP-contaminated soil. The process treats waste in
the form of a slurry or sludge. Soils are mixed with water to form a slurry of approximately 20
percent solids prior to treatment. Waste is placed into the bioreactor and air is introduced
for mixing and aeration. A nutrient and inoculum solution is added to the bioreactor as needed.
Mechanical mixing devices are often reguired to ensure a homogeneous mixture in the reactor
vessel. The contaminants are biologically degraded as they move to the agueous phase through
biological or chemical/physical action. The treated solids reguire dewatering prior to final
disposal of the material. This alternative was not retained for detailed analysis.

7.1.6 Excavation and Disposal (Offsite) (Alternative 13-6)

This alternative includes the excavation of all BAP-contaminated soils, staging of soils, and
loading of trucks for transportation to the Chemical Waste Management hazardous waste
incineration facility in Port Arthur, Texas, via the Emelle, Alabama, facility for treatment and
disposal. A single truck with a 22-ton payload would be reguired to transport the estimated
11.85 yd3 of contaminated soils. Once at the facility, the waste would be incinerated and a
TCLP test would be conducted prior to disposal in the landfill. This alternative was retained
for detailed analysis.

7.2 Study Area 14 Alternatives

7.2.1 No Action (Alternative 14-1)

No action is taken to reduce constituent concentrations in soil media. The no action
alternative is used as a baseline for comparison with the other soil media alternatives.

7.2.2 In Situ Bioremediation (Electrokinetic) (Alternative 14-2)

This alternative uses in situ bioremediation to treat metals-contaminated soil. The innovative
technology of bio-electrokinetics is based on the principle of accelerated movement of
groundwater in subsurface sands, silts, and clay. Increased groundwater flow is induced by
application of a direct current over graphite electrodes immersed in the soil media. The
groundwater in the immediate vicinity of the electrodes is electrolyzed. Hydrogen ions are
generated at the anode and hydroxyl ions are generated at the cathode. A clay-derived acid is
formed at the anode. The clay-derived acid provides the transport mechanism for movement of
contaminants. The movement of the concentrated acid is by the advection of pore fluid due to
prevailing electro-osmotic flow, and the internally or externally applied hydraulic potential
differences, diffusion from concentration gradients, and ion migration due to electrical
gradients. (Remediation of Hazardous Waste Contaminated Soils, 1994). This alternative was not
retained for detailed analysis.

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7.2.3 Excavation, Solidification/Stabilization, and Disposal (Onsite) (Alternative 14-3)

This alternative includes the excavation of all contaminated soils. Following excavation, soils
will be screened and solidified/stabilized prior to on-site disposal. Solidification/
stabilization of lead-contaminated soils from Study Area 14 (Cannon Range) would be accomplished
using a mobile mixing plant (pug mill) to handle, meter, and mix the reagents with the
contaminated soils. A typical mobile mixing plant consists of a silo for storage of the cement,
a weight batcher to control the cement feed, and a ribbon blender for mixing the reagents and
the waste. A typical mobile mixing plant is capable of solidifying/stabilizing waste materials
at a rate of 50 to 75 yd3per hour. Front-end loaders would be used to load the pre-staged
contaminated soils into a feed hopper.

The solidification/stabilization technigue selected for the lead-contaminated soils found in
Study Area 14, is a pozzolan-Portland cement system. The process is generally the least
expensive, most adaptable, and most versatile of the solidification processes and is compatible
with the waste constituents in Study Area 14 soils. The process is expected to reguire
additional curing time due to the clayey nature of soils found within Area A of ALAAP. This
system uses Portland cement and pozzolan (fine-grained, reactive silica) to bind the
contaminated soils into a solidified matrix. Free calcium hydroxide in the cement is bound to
the waste, thus improving the strength and chemical resistivity of the final product. Other
materials may be added to change the physical characteristics of the final product, such as the
solubility of wastes, setting time, and, final strength. TCLP analyses would be conducted on
the solidified material to verify that the matrix meets TCLP criteria. This alternative was
retained for detailed analysis.

7.2.4 Excavation, Detoxification, and Disposal (Onsite) (Alternative 14-4)

This alternative includes excavation of all contaminated soils within Study Area 14. Once
excavated, the soils will be classified (screened) to remove solid debris in preparation for
treatment. This alternative uses the synergetic application of specific inorganic and organic
reagents that readily percolate through the contaminated soils. The reagents react with the
metals in the soils. The redox reaction reduces the valence of the metals to the lowest state
and renders the metals insoluble as stable organometallic complexes. The resulting precipitate
is essentially insoluble and tends to increase its insolubility with time. This alternative was
not retained for detailed analysis.

7.2.5 Excavation, Acid Extraction, and Disposal (Onsite) (Alternative 14-5)

This alternative includes excavation of all contaminated soils within Study Area 14. Once
excavated, the soils will be classified (screened) to remove solid debris in preparation for
treatment. This alternative involves soil washing, leaching, mixing, centrifugation, additional
leaching in a horizontal washer and metal recovery via ion exchange. The process is continued
until desired constituent concentrations are obtained. The treated soils are reblended and
neutralized before discharge for onsite disposal. This alternative was not retained for
detailed analysis.

7.2.6 Excavation and Disposal (Offsite) (Alternative 14-6)

This alternative includes the excavation of all contaminated soils, staging of soils, and
loading of trucks for transportation to the Chemical Waste Management hazardous waste landfill
facility in Emelle, Alabama, for treatment and disposal. A total of three trucks with 22-ton
payloads would be reguired to transport the estimated 46.3 yd3, of contaminated soils. Once at
the facility, the waste would be solidified/stabilized and a TCLP test would be conducted prior
to disposal in the landfill. This alternative was retained for detailed analysis.

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8.0 Summary of the Comparative Analysis of Alternatives

Two interim response actions were completed at the site prior to issuing this document. The
first action, completed in 1986 to 1987 was accomplished without the issuance of an interim ROD.
This action was initiated prior to the site being placed on the NPL in July 1987. In this
action, soils considered to be contaminated were excavated from within Area A and transported to
Area B without any treatment being completed. These soils subseguently became the Stockpile
Soils OU within Area B of the Installation. A ROD for the Stockpile Soils OU was issued in
December 1991 and recommended incineration as the preferred alternative.

During the initial stages of the supplemental investigations, it was determined that soils in
Study Areas 12 and 30 contained lead and explosives at unacceptable concentrations. An interim
ROD for soils in Study Areas 12 and 30 was submitted in April 1994, which recommended
incineration as the preferred alternative.

Supplemental investigations were completed following the second remedial action. This
investigation included collecting samples from all media within all study areas to determine the
contamination status of the site following the completion of the interim response actions.
These investigations determined that Soils within Study Areas 13 and 14 contained PAHs and lead
at unacceptable concentrations. The RA completed for the site, based on data collected after
the completion of all interim response actions, determined that all remaining study areas
gualified for No Further Action.

Presented within each of the completed interim RODs is the detailed Summary of Comparative
Analysis of Alternatives selecting the final alternative for each interim action. The remainder
of this section details alternatives presented to complete this final remedial action.

8.1 Threshold Criteria

8.1.1 Overall Protection of Human Health and the Environment

Upon completion of Alternatives 13-2, 13-6, 14-3, and 14-6, the contaminant concentrations in
the soils in Study Areas 13 and 14 within Area A would be reduced to levels that are protective
of human health and the environment through excavation, treatment, and disposal outside of
Area A of contaminated soils from the Study Areas. Alternative 13-1 and 14-1 would not be
protective of human health or the environment since contaminants would be left in the soils and
risks to the community, workers, and the environment would remain.
8.1.2 Compliance with ARARs

No federal or state chemical-specific ARARs regulate implementation of any of the alternatives.
Soils will be remediated according to health-based cleanup levels determined to be protective to
human health and the environment. Completion of Alternatives 13-2, 13-6, 14-3, and 14-6 would
achieve the health- and risk-based cleanup levels.

With Alternatives 13-1 and 14-1, the contaminated soils would be left onsite, untreated, and
would not achieve the remediation levels since the contamination would not be removed or
destroyed.

The following location-specific ARARs may be applicable within ALAAP:

• Within 100-year floodplain: Resource Conservation and Recovery Act (RCRA): 40 CFR
264.18(b)--Facility must be designed, constructed, operated, and maintained to
avoid washout by a 100-year flood.

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              Within floodplain:   Executive Order 11988;  40 CFR 6,  App.  A:   Floodplain Management
              --Requires actions  to avoid adverse effects,  minimize floodplain destruction,
              restore and preserve natural and beneficial values,  and minimize impact of floods on
             human safety, health, and welfare.
              Wetland:   Executive Order 11990; 40 CFR 6,  App.  A:   Protection of Wetlands—Requires
              action to avoid adverse impact,  minimize potential  harm,  and to preserve and enhance
              wetlands  to the extent possible.
       •      Within an area affectinq stream or river:   Fish and Wildlife Coordination Act [16
              United States Code   (USC)  661 et seq.]--Must take action to protect affected fish or
              wildlife  resources, and prohibits diversion,  channelinq,  or other activity that
              modifies  a stream or river and affects fish or wildlife.   40 CFR Part 230--Section
              404(b)(1)  Guidelines For Specification of Disposal  Sites For Dredqed Or Fill
              Material--The purpose of these Guidelines is to restore and maintain the chemical,
              physical,  and bioloqical inteqrity of waters of the United States throuqh the
              control of discharqes of dredqed or fill material.
       •      Critical  habitat upon which endanqered or threatened species depends:  Endanqered
              Species Act of 1973 (16 USC 1531 et seq.);  50 CFR 402—Requires action to conserve
              endanqered or threatened species.  Must not destroy or adversely modify critical
              habitat.
              Aquatic Systems:  Section 404 of the Clean Water Act—Dredqe and Fill Standards
              --requlates the discharqe of dredqed or fill material into waters of the U.S.
              This proqram is implemented throuqh requlations set forth at 33 CFR Parts 320 and
              330 and 40 CFR Part 230.   These requlatory requirements ensure that proposed
              discharqes are evaluated with respect to impacts on the aquatic ecosystem.

However, none of the location-specific ARARs are expected to apply to implementinq any of the
alternatives beinq evaluated since all activities associated with the Area.  A remediation would
be conducted in areas located away from sensitive environment  (i.e., the river, 100-year
floodplain, or critical habitat).

The followinq action-specific ARARS may apply to implementinq of these alternatives, excludinq
Alternatives 13-1 and 14-1  (No Action):

       Clean Air Act (CAA) :
              40 CFR Part 50:  National Primary and Secondary Ambient Air Quality
              Standards—Establishes standards for ambient air quality to protect public health
              and welfare.
              40 CFR Part 61:  National Emission Standards for Hazardous Air
              Pollutants—Sets emission standards for desiqnated hazardous pollutants.

       RCRA
              40 CFR Part 261:   Identification and Listinq of Hazardous Waste—Provides
              quidelines for classifyinq wastes as hazardous waste.
              40 CFR Part 262:   Standards Applicable to Generators of Hazardous
              Waste—Establishes  standards for qenerators of hazardous waste.
              40 CFR Part 264:   Standards for Owners and Operators of Hazardous Waste
              Treatment, Storaqe, and Disposal Facilities—Establishes minimum national
              standards which define the acceptable manaqement of hazardous waste for
              owners and operators of facilities which treat, store, or dispose of hazardous
              waste.

       Alabama Administrative Code (AAC)
              Chapters 13-1 throuqh 13-7:  Alabama Solid Waste Manaqement
              Requlations—Establishes minimum criteria for the processinq, recyclinq and

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disposal of solid wastes and the design, location, and operation of solid waste
disposal facilities.
Chapters 335-3-1 through 335-3-14: Alabama Air Pollution Control Rules and
Regulations—Sets emission standards and establishes permitting reguirements
for air pollutants.
Chapter 335-14-5.15(4) (a)l: Performance Standards for Incinerators — Provides
standards for the performance of incinerators. Incinerators treating hazardous
wastes must provide at least 99.99 percent destruction efficiency for each
principal organic hazardous constituent.

• Code of Alabama
Title 22, Chapter 27: Alabama Solid Waste Act—Establishes a statewide
program to provide for the safe management of nonhazardous wastes.
Title 22, Chapter 28: Alabama Air Pollution Control Act of 1971—Provides for
a coordinated statewide program of air pollution prevention, abatement, and
control.
Title 22, Chapter 30: Alabama Hazardous Waste Management and
Minimization Act-Establishes a statewide program to provide for the safe
management of hazardous wastes, including hazardous waste generation,
transportation, and land disposal.

ADEM
Chapter 14-1: Alabama Hazardous Waste Management
Regulations—Establishes standards that define the acceptable management of
hazardous waste for owners and operators of facilities that treat, store, or
dispose of hazardous waste.

8.2 Primary Balancing Criteria

8.2.1 Short-Term Effectiveness

Upon completion of remedial activities, Alternatives 13-2, 13-6, 14-2, and 14-6 would satisfy
the remedial action objectives. Residual soil concentrations in Study Areas 13 and 14 within
Area A would be below the remediation levels. No significant risks to the community, the
workers implementing remedial actions; or the environment are expected during implementation of
these four alternatives, provided that proper safety precautions are taken. During the
excavation phase of these alternatives, appropriate precautions, such as the construction of
surface runoff controls and the proper containment and covering of excavated soils, would reduce
impacts to the environment. During the transportation phase, appropriate RCRA and DOT
guidelines for transporting hazardous wastes would be followed to reduce impacts to the
environment and the community. Primary risks to workers would be reduced by wearing protective
clothing, designating exclusion zones for excavation areas, and adhering to proper
decontamination procedures.

It is expected that each of these alternatives could be completed in less than 6 weeks. Based on
a comparison of these three alternatives, no difference exists in their short-term
effectiveness. Alternative 13-1 and 14-1 would present unacceptable risks to human health and
the environment since no remediation of the contaminated soils would occur; therefore, this
alternative would not be effective in the short term.

8.2.2 Long-Term Effectiveness and Permanence

Alternatives 13-2, 13-6, 14-3 and 14-6 would be effective in reducing the long-term risk of
exposure at Study Areas 13 and 14 within Area A. With these alternatives, the magnitude of

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residual risks will be removed as all of the contaminants are excavated and removed from Study
Areas 13 and 14 within Area A.  No treatment residuals or untreated wastes would remain in
Study Areas 13 and 14 within Area A following completion of this interim action.  Alternatives
13-1 and 14-1 would not be effective in the long term since the contamination sources would
remain intact, yielding no reduction in the unacceptable pathways or associated risks.

8.2.3  Reduction of Contaminant MTV

Alternatives 13-2, 13-6, 14-3, and 14-6 would reduce onsite MTV within Study Areas 13 and 14
within Area A.  Treatment of the contaminated soils would result in a significant decrease in
toxicity and a slight decrease in volume of material.  Because the contaminants in the soils
would not be destroyed, removed, or treated under Alternatives 13-1 and 14-1, the MTV of the
contaminants would remain unchanged.

8.2.4  Implementability

All retained alternatives are technically and administratively feasible.  Alternatives 13-2,
13-6, 14-3, and 14-6 are all implementable, with reguired labor, eguipment, and materials
available from various suppliers near ALAAP.  Alternative 13-2 and 14-3 would reguire
treatability tests. No remedial actions would be implemented for Alternative 13-1 and 14-1.

8.2.5  Cost

The total present-worth costs of remediation, based on 1996 unit costs are $48,420 for
Alternative 13-2; $40,351 for Alternative 13-6; $10,387 for alternative 14-3; and $38,938 for
Alternative 14-6.  These costs include construction costs, O&M costs (alternatives 13-2 and 14-3
only), engineering, and contingency fees.  No cost is associated with Alternatives 13-1 and
14-1.

8.3  Modifying Criteria

8.3.1  ADEM/EPA Acceptance

EPA and ADEM have concurred with the choice of Alternatives 13-6 and 14-3.

8.3.2  Community Acceptance

In accordance with the Army's CRP for ALAAP, October 1990, the FS and the Proposed Plan for this
ROD were released to the public on August 16, 1996.  The public comment period began August 16,
1996, and ended September 15, 1996.  Documents were made available to the public at the Earle A.
Rainwater Memorial Library, Childersburg, Alabama.  The notice of availability of the Proposed
Plan was published in the Daily Home and the Birmingham News on August 15, 1996.

In accordance with the CRP, a public meeting was held at Central Alabama Community College on
September 10, 1996, to inform the public of the preferred alternative and to seek public
comments.  At this meeting, representatives from ALAAP, EPA, ADEM, USAGE, and USAEC were present
and answered guestions about the site and the remedial alternatives under consideration.  No
comments in opposition to the preferred alternative were voiced at the meeting or presented
during the public comment period.

A response summary to the public comments received during the public comment period and hearing
is included in the Responsiveness Summary section of this report.

9.0  Selected Remedy and Remediation Levels

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9.1 Completed 1986 to 1987 Interim Action

The 1986 to 1997 interim action was a removal action only, completed without the issuance of an
interim ROD. This action was initiated prior to the site being included in the NPL in July,
1987. Soils were treated at a later date under an interim ROD in Area B of ALAAP. The selected
alternative called for implementing an interim response action to protect human health and the
environment from the contaminated soil in Study Areas 11, 12, 13, 15, 17, 29, 30, 31, 32, 33,
and 34 within Area A at ALAAP. This action was an interim action for only the contaminated
soils in the identified Study Areas within Area A.

Based on the CERCLA reguirements and a screening of the alternatives, ALAAP, in consultation
with EPA and ADEM, had determined that the selected alternative was the most appropriate remedy
for soils in Study Areas 11, 12, 13, 15, 17, 29, 30, 31, 32, 33, and 34 within Area A at ALAAP.

The interim remedy for soils in Study Areas 11, 12, 13, 15, 17, 29, 30, 31, 32, 33, and 34
within Area A at ALAAP for source control included:

• Excavation of approximately 21,400 yd3 of lead- and explosives-contaminated soils
from Study Areas 11, 12, 13, 15, 17, 29, 30, 31, 32, 33, and 34 within Area A
• Transportation of contaminated soils to Area B for final treatment
• Onsite treatment (in Area B) by incineration followed by solidification/stabilization (of
lead contaminated soils when reguired) or solidification only (if applicable) of
lead-contaminated soils.
• Onsite disposal of treated soil at a designated area in Area B

The remediation level [in micrograms per gram (Ig/g)] for excavation of contaminated soil at
Study Areas 11, 12, 13, 15, 17, 29, 30, 31, 32, 33, and 34 within Area A were calculated using
the preliminary pollutant limit value (PPLV) approach developed by the U.S. Army Medical
Bioengineering Research and Development Laboratory (Rosenblatt and Small, 1981). The PPLV
approach involves the development of health-based cleanup goals based on risk assessment
procedures. The PPLVs used as cleanup goals within Area A were as follows:
2,4-DNT
2 , 6-DNT
2,4, 6-TNT
1,3-DNB
1,3,5-TNB
Tetryl
Lead
0.42
0.40
1.92
1.1
5.5
1.7
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Lead-contaminated materials that result in a TCLP extract in excess of 5 mg/L are considered
hazardous under RCRA. Explosives-contaminated material that is ignitable or reactive is
considered hazardous waste under RCRA.

Implementing the selected interim action resulted in the removal from Study Areas 11, 12, 13,
15, 17, 29, 30, 31, 32, 33 and 34 within Area A of all identified contaminated soils at
concentrations above the remediation levels as presented, resulting from DOD operations.

Excavated soils were stockpiled in Area B of ALAAP within a building and on a concrete pad
covered with a membrane liner. An FS was completed for the stockpile soils, now within Area B,
in October 1991. A ROD for the Stockpile Soils Area OU (part of Area B) was issued in December
1991 and recommended incineration as the preferred alternative. The incineration of Stockpile
Soils commenced in May 1994 and was completed in August 1994.

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Implementing the selected remedy met the following standards for treating the COCs in the
excavated soils from soils in Study Areas 11, 12, 13, 15, 17, 29, 30, 31, 32, 33,  and 34 within
Area A:

•      Explosives--The ash generated from the incineration of explosives-contaminated soil was
       tested for destruction of explosives,  as reguired by RCRA.
•      Lead-Concentration of less than 5 mg/L in the TCLP extract,  as reguired by RCRA.
•      Particulate Emissions—Routine analysis of stack gases was performed to ensure processes
       were operating efficiently and within acceptable air emissions standards for the  State of
       Alabama.
•      Confirmatory sampling along with remediation was conducted to include broad scan  analyses,
       following the remediation to ensure that all contaminants of concern resulting from DOD
       operations that would pose a risk to public health or the environment had been addressed.

9.2  Completed 1994 Interim Action

The selected alternative called for implementing an interim response action to protect human
health and the environment from the contaminated soil in Study Areas 12 and 30 within the Area A
Soil OU at ALAAP.  This action was an interim action for only the contaminated soils in Study
Areas 12 and 30 within Area A.

Based on the CERCLA reguirements and the detailed analysis of the alternatives, ALAAP, in
consultation with EPA and ADEM, had determined that the selected alternative was the most
appropriate remedy for soils in Study Areas 12 and 30 within Area A.

The interim remedy for soils in Study Areas 12 and 30 within Area A for source control included:

•      Excavating approximately 3,800 yd3 of lead-contaminated soils from Study Area 12  and 5 yd3
       of explosives-contaminated soils from Study Area 30
•      Transporting contaminated soils to Area B for final treatment
•      Onsite treatment (in Area B)  by incineration followed by solidification/stabilization (of
       lead contaminated soils when reguired)  or solidification only (if applicable)  of  lead
       contaminated soils.
•      Onsite disposal of treated soil at a designated area in Area B.

The remediation level for excavation of 2,4,6-TNT-contaminated soil at Study Area 30 in Area A
was 21 mg/kg, a health-based level developed using EPA RA methodology.  The remediation level for
excavation of lead-contaminated soil at Study Area 12 in Area A was 400 mg/kg, the guidance
level established by EPA.

Lead-contaminated materials that result in a TCLP extract in excess of 5 mg/L are considered
hazardous under RCRA.  Explosives-contaminated material that is ignitable or reactive is
considered hazardous waste under RCRA.

Implementing the selected interim action resulted in the removal of all contaminated soils at
concentrations above the remediation levels of 21 mg/kg for 246TNT and 400 mg/kg for lead
resulting from DOD operations from Study Areas 12 and 30 within Area A.  Implementing the
selected remedy also met the following standards for treating the COCs in the excavated soils
from soils in Study Areas 12 and 30 within Area A:

•      Explosives--The ash generated from the incineration of explosives-contaminated soil
       was tested for destruction of explosives,  as reguired by RCRA.
•      Lead-Concentration of less than 5 mg/L in the TCLP extract,  as reguired by RCRA.
•      Particulate Emissions—Routine analysis of stack gases was performed to ensure processes

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       were operating efficiently and within acceptable air emissions standards for the state of
       Alabama.
•      Confirmatory sampling along with remediation was conducted to include broad scan
       analyses,  following the remediation to ensure that all contaminants of concern resulting
       from DOD operations that would pose a risk to public health or the environment had been
       addressed.

9.3  Proposed Final Action

The selected alternatives (Alternative 13-6 and 14-3) reguire implementing a remedial action to
protect human health and the environment from the contaminated soil in Study Areas 13 and 14
within the Area A at ALAAP.   This action is a final action for the contaminated soils in all
Study Areas within Area A.  Interim actions completed have been shown to be sufficient.  The
Risk Assessment completed for the site, based on data collected after the completion of all
interim response actions, determined that all remaining study areas gualified for No Further
Action.

Based on the CERCLA reguirements and the detailed analysis of the alternatives, ALAAP, in
consultation with EPA and ADEM, has determined that Alternatives 13-6 and 14-3 are the most
appropriate remedies for soils in Area A.

The final remedy for soils in Study Areas 13 and 14 within Area A for source control includes:

•      Excavation of approximately 12 yd3 of PAH-contaminated soils from Study Area 13 and 46 yd3
       of lead-contaminated soils from Study Area 14
•      Transporting contaminated soils from Study Area 13 to a waste incineration facility in
       Port Arthur,  Texas
•      Onsite solidification of soils from Study Area 14
•      Onsite disposal of treated soil from Study Area 14 at designated area in Area B

Since the selected alternatives can be completed in a short time period, no periodic O&M costs
associated with the incinerator are expected.  The following are the costs for the selected
remedies for Study Areas 13 and 14.

Study Area 13

   Estimated Construction Cost                               $40,351
   Estimated O&M Cost                                        None
   Estimated Total Present—Worth Cost, including
        Engineering and Contingency                          $40,351

Study Area 14

   Estimated Construction Cost                               $10,387
   Estimated O&M Cost                                        None
   Estimated Total Present—Worth Cost, including
        Engineering and Contingency                          $10,387

The remediation level for excavation of benzo(a)pyrene-contaminated soil at Study Area 13 in
Area A is 7 mg/kg.  The remediation level for excavation of lead-contaminated soil at Study
Area 13 in Area A is 400 mg/kg.

Implementing the selected interim action will result in the removal of all contaminated soils at
concentrations above the remediation levels from Study Areas 13 and 14 within Area A.  The Risk

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Assessment completed for the site, based on data collected after the completion of all interim
response actions, determined that all remaining study areas qualified for No Further Action.
The completion of this final action along with the completed interim actions will result in no
further risk present within any media in any study area.

10.0 Statutory Determinations

Remedial investigations have progressed at the site since 1980, and two interim response actions
were completed. At the completion of all interim response actions, a supplemental investigation
was performed to determine the contamination status of all media (soil, groundwater, surface
waters, sediments) at the site following remediation. Samples were collected from all study
areas, including those that had undergone interim removal actions. A Final Remedial
Investigation Report and Risk Assessment were completed using the data collected during the
supplemental investigation along with previously collected data. Based on this complete data
set of the site as it exists now, the Risk Assessment determined that the only sites that
continue to present an unacceptable human health risk were Study Areas 13 and 14, and that no
study areas within Area A present an unacceptable ecological risk. Interim response actions
completed at other study areas were determined to be sufficient to be protective of human
health, welfare, and the environment.

This final remedial action (Study Areas 13 and 14) is being taken to protect human health and
the environment from unacceptable risks. This action is the final action for all media within
Area A. All other study areas within Area A have been approved for No Further Action.

10.1 Completed 1986 to 1987 Interim Action

The 1986 to 1987 interim action was a removal action only, completed without the issuance of an
interim ROD. This action was initiated prior to the site being included in the NPL in July
1987. Soils were treated at a later date under an interim ROD in Area B of ALAAP. The completed
interim alternative called for implementing an interim response action to protect human health
and the environment from the contaminated soil in Study Areas 11, 12, 13, 15, 17, 29, 30, 31,
32, 33, and 34 within Area A. This action was an interim action for only the contaminated soils
in the identified study areas within Area A.

The completed interim alternative satisfied the requirements under Sec. 121 of CERCLA to:

• Protect human health and the environment,
Comply with ARARs,
• Be cost effective,
• Use permanent solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable, and
• Satisfy the preference for treatment as a principal element.

10.1.1 Protection of Human Health and the Environment

The completed interim alternative protects human health and the environment through excavation,
treatment, and disposal of contaminated soils from Study Areas 11, 12, 13, 15, 17, 29, 30, 31,
32, 33, and 34 within Area A.

During remediation activities, adequate protection was provided to the community by reducing the
short-term risks posed by air emissions from the thermal treatment unit and reducing dust
potentially generated during material excavation and handling activities. In addition, workers
were provided with personal protection equipment during all phases of remediation activities.

-------
Long-term protection to human health and the environment was provided by leaving no residual
risk from the DOD-related contaminants and reducing or eliminating the impact on the
environment.

Controls employed in the alternative were adeguate and reliable. This completed interim
alternative had no unacceptable short-term or long-term impacts on human health or the
environment.

10.1.2 Compliance with ARARs

The completed interim alternative complied with all ARARs. All the COCs in soils of Study
Areas 11, 12, 13, 15, 17, 29, 30, 31, 32, 33, and 34 within Area A at ALAAP had met reguired
regulatory treatment/disposal standards prior to disposal.

No federal or state chemical-specific ARARS prevented implementing the completed interim
alternative. Soils were removed based on health-based cleanup levels determined to be
protective to human health and the environment.

No location-specific ARARS prevented the use of the completed interim alternative. All
activities associated with implementing this alternative were conducted away from sensitive
environments (i.e., river or 100-year floodplain).

The following action-specific ARARS will be met with implementation of this alternative:

• Workers were provided with personal protection eguipment (PPE) during all phases of the
completed interim remedy, in compliance with the Occupational Safety and Health Act (OSHA)
(29 USC ss. 651-678). Adeguate protection was provided to the community by reducing dust
potentially generated during material excavation and handling activities.

If the excavated soils were determined to be a hazardous waste, the following action-specific
ARARS would be applicable:

• Wastes will be properly classified under guidelines for RCRA (40 CFR Part 261:
Identification and Listing of Hazardous Waste and 40 CFR Part 262: Standards Applicable
to Generators of Hazardous Waste) and the State of Alabama (Code of Alabama, Title 22,
Chapter 30: Alabama Hazardous Waste Management and Minimization Act and ADEM Chapter
14-1: Alabama Hazardous Waste Management Regulations).

10.1.3 Cost Effectiveness

The completed interim remedies for soils in Study Areas 11, 12, 13, 15, 17, 29, 30, 31, 32, 33,
and 34 within Area A had been determined to provide overall effectiveness proportionate to its
costs.

10.1.4 Use of Permanent Solutions and Alternative Treatment Technologies or Resource
Recovery Technologies to the Maximum Extent Practicable

The selected interim action was not designed or intended to be a final action for all soils
within Area A but rather was intended to address only the soils within Study Areas 11, 12, 13,
15, 17, 29, 30, 31, 32, 33, and 34 within Area A. As such, the alternative meets the statutory
reguirements to use permanent solutions and treatment technologies to the maximum extent
practicable to achieve remediation goals at only these two study areas. The criteria used in
selecting the alternative include:

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• Short-term Effectiveness—The completed interim alternative did not involve off-facility
transportation of contaminated soils, thereby eliminating the risks to the community due
to spillage and dust emissions. The community, workers, and environment were protected
during remedial actions by implementing appropriate protective measures. Long-Term
Effectiveness and Permanence—The completed interim alternative provided for remediation
of contaminated soils from Study Areas 11, 12, 13, 15, 17, 29, 30, 31, 32, 33, and 34
within Area A. Direct exposure pathways were eliminated until the soils could be
remediated. Upon treatment, the magnitude of residual risks were removed as all of the
contaminants were treated and disposed of in accordance with applicable regulations.
• Reduction of Contaminant MTV—Contaminant mobility was significantly decreased due to the
placement of the contaminants in lined storage buildings. Contaminant toxicity and soil
volume was reduced upon final treatment.
• Implementability--All elements of the completed, interim alternatives were performed on
site. Reguired labor, eguipment, and materials were available from various suppliers
near ALAAP.
• Cost—The completed interim remedies for soils in Study Areas 11, 12, 13, 15, 17, 29, 30,
31, 32, 33, and 34 within Area A were determined to provide overall effectiveness
proportionate to its cost.

10.1.5 Preference for Treatment as a Principal Element

The completed interim action used removal only. Treatment was completed within Area B under a
separate interim ROD.

10.2 Completed Interim Action for Study Areas 12 and 30

The completed interim alternative called for implementing an interim response action to protect
human health and the environment from the contaminated soil in Study Areas 12 and 30 within
Area A at ALAAP. This action was an interim action for only the contaminated soils in Study
Areas 12 and 30 within Area A.

The completed interim alternative satisfied the reguirements under Sec. 121 of CERCLA to:

• Protect human health and the environment
Comply with ARARs
• Be cost effective
• Use permanent solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable
• Satisfy the preference for treatment as a principal element.

10.2.1 Protection of Human Health and the Environment

The completed interim alternative protected human health and the environment through
excavation, treatment, and disposal of contaminated soils from Study Areas 12 and 30 within
Area A.

During remediation activities, adeguate protection was provided to the community by reducing the
short-term risks posed by air emissions from the thermal treatment unit and reducing dust
potentially generated during material excavation and handling activities. In addition, workers
were provided with personal protection eguipment during all phases of remediation activities.

Long-term protection to human health and the environment was provided by leaving no residual
risk from the DOD-related contaminants and reducing or eliminating the impact on the
environment.

-------
Controls employed in the alternative were adequate and reliable.  This alternative had no
unacceptable short-term or long-term impacts on human health or the environment.

10.2.2  Compliance with ARARs

The completed interim alternative complied with all ARARs.  All the COCs in soils of Study
Areas 12 and 30 within Area A (i.e., explosives and lead) met required regulatory
treatment/disposal standards prior to disposal.

No federal or state chemical-specific ARARS prevented implementing the completed interim
alternative.  Soils were removed based on health-based cleanup levels determined to be
protective to human health and the environment.  Lead-contaminated soils were remediated to
achieve the health-based soil lead concentration of 500 mg/kg (based on blood-lead uptake levels
in children).  Soils contaminated with 246TNT were remediated to achieve the health-based soil
246TNT concentration of 21 mg/kg  (based on the resultant risk for adult residents and the
contributing HI due to exposure concentration for child residents).

No location-specific ARARS prevented the use of the completed interim alternative.  All
activities associated with implementing this alternative were conducted away from sensitive
environments (i.e., river or 100-year floodplain).

The following action-specific ARARS were met with implementation of this alternative:

•      Incinerator ash was routinely tested for destruction of explosives,  as required by RCRA
       (40 CFR Part 264:   Standards for Owners and Operators of Hazardous Waste Treatment,
       Storage,  and Disposal Facilities)  and the state of Alabama [Alabama Administrative Code
       Chapter 335-14-5.15(4)(a)l:  Performance Standards for Incinerators)
•      TCLP extract analysis on incinerator ash was performed to ensure lead concentrations in
       the treated soil were less than 5 mg/L prior to disposal, as  required by RCRA (40 CFR
       Part 264:  Standards for Owners and Operators of Hazardous Waste Treatment, Storage, and
       Disposal Facilities).  Incinerator ash that did not pass TCLP was solidified/stabilized
       prior to disposal.
•      Incinerator ash and solidified/stabilized material (if required)  was disposed of onsite in
       Area B  in accordance with RCRA (40 CFR Part 264:  Standards for Owners and Operators of
       Hazardous Waste Treatment, Storage,  and Disposal Facilities)  and the State of Alabama
       (Code of Alabama,  Title 22, Chapter 27:  Alabama Solid Waste  Act and Alabama
       Administrative Code Chapters 13-1 through 13-7:  Alabama Solid Waste Management
       Regulations).
•      Routine analysis of stack gases was performed to ensure incinerator processes were
       operating efficiently and within acceptable air emissions standards,  as required by the
       CAA  (40 CFR Part 50:   National Primary and Secondary Ambient  Air Quality Standards and 40
       CFR Part 61:  National Emission Standards for Hazardous Air Pollutants)  and the State of
       Alabama  (Code of Alabama,  Title 22,  Chapter 28:  Alabama Air  Pollution Control Act of 1971
       and Alabama Administrative Code Chapters 335-3-1 through 335-3-14:  Alabama Air Pollution
       Control Rules and Regulations).
•      Workers were provided with PPE during all phases of the completed interim remedy, in
       compliance with OSHA (29 USC ss.  651-678) .  Adequate protection was provided to the
       community by reducing risks posed by air emissions from the thermal treatment unit and
       reducing dust potentially generated during material excavation and handling activities.

If excavated soils were determined to be a hazardous waste, the following action-specific ARARS
were applicable:

•      Wastes  were properly classified under guidelines for RCRA  (40 CFR Part 261: Identification

-------
and Listing of Hazardous Waste and 40 CFR Part 262: Standards Applicable to Generators of
Hazardous Waste) and the State of Alabama (Code of Alabama, Title 22, Chapter 30: Alabama
Hazardous Waste Management and Minimization Act and ADEM Chapter 14-1: Alabama Hazardous
Waste Management Regulations).

10.2.3 Cost Effectiveness

The completed interim remedy for soils in Study Areas 12 and 30 within the Area A have been
determined to provide overall effectiveness proportionate to its costs. Although this
alternative was more expensive than other alternatives screened, it took advantage of the
special eguipment, operators, site preparation, and treatment system mobilization already in
place for treatment of the Stockpile Soils Area OU.

10.2.4 Use of Permanent Solutions and Alternative Treatment Technologies or Resource
Recovery Technologies to the Maximum Extent Practicable

The completed interim action was not designed or intended to be a final action for all soils
within Area A but rather was intended to address only the soils within Study Areas 12 and 30.
As such, the alternative met the statutory reguirements to use permanent solutions and treatment
technologies to the maximum extent practicable to achieve remediation goals at only these two
study areas. The criteria used in selecting the alternative included:

• Short-term Effectiveness--The completed interim alternative did not involve off-facility
transportation of contaminated soils, thereby eliminating the risks to the community due
to spillage and dust emissions. The community, workers, and environment were protected
during remedial actions by implementing appropriate protective measures.
• Long-Term Effectiveness and Permanence--The completed interim alternative provided for
remediation of contaminated soils from Study Areas 12 and 30 within Area A. Direct
exposure pathways were eliminated until the soils could be remediated with the Stockpile
Soils Area OU. Upon treatment, the magnitude of residual risks was removed as all of the
contaminants were treated and disposed of in accordance with applicable regulations.
• Reduction of Contaminant MTV—Contaminant mobility was significantly decreased due to the
placement of the contaminants in lined storage buildings. Contaminant toxicity and soil
volume was reduced upon treatment along with the Stockpile Soils Area OU.
• Implementability--All elements of the completed interim alternative were performed onsite.
Reguired labor, eguipment, and materials were available from various suppliers near ALAAP.
Treatment of contaminated soil did not reguire any additional special eguipment or system
mobilization since these components were already be in place for the Stockpile Soils Area
OU.
• Cost—Although the completed interim remedy was more expensive, it took advantage of
special eguipment and thermal treatment system mobilization costs that were incurred
during treatment of the Stockpile Soils Area OU.

10.2.5 Preference for Treatment as a Principal Element

The completed interim action used treatment for the soils of Study Areas 12 and 30 within the
Area A Soils OU. Any additional reguired actions for these two Study Areas as well as for all
the soils of Area A are addressed (Section 10.3) in this final Decision Document for Area A.

10.3 Proposed Final Action

The selected alternative satisfies the reguirements under Sec. 121 of CERCLA to:

• Protect human health and the environment

-------
Comply with ARARs
• Be cost effective
• Use permanent solutions and alternative treatment technologies or resource recovery
technologies to the maximum extent practicable
• Satisfy the preference for treatment as a principal element.

The RA completed for the site, based on data collected after the completion of all interim
removal actions, determined that all remaining study areas gualified for No Further Action.

10.3.1 Protection of Human Health and the Environment

The selected alternative protects human health and the environment through excavation,
treatment, and disposal of contaminated soils from Study Areas 13 and 14 within the Area A. The
Risk Assessment completed for the site, based on data collected after the completion of all
interim removal actions, determined that all remaining study areas gualified for No Further
Action.

During removal activities, adeguate protection will be provided to the community by reducing the
short-term risks posed by air emissions from the thermal treatment unit and reducing dust
potentially generated during material excavation and handling activities. In addition, workers
will be provided with PPE during all phases of remediation activities.

Long-term protection to human health and the environment will be provided by leaving no
residual risk from the DOD-related contaminants and reducing or eliminating the impact on the
environment.

Controls employed in the alternative are adeguate and reliable. This alternative has no
unacceptable short-term or long-term impacts on human health or the environment.

10.3.2 Compliance with ARARs

The selected alternative complies with all ARARs. All the COCs in soils of Study Areas 13 and
14 within Area A are expected to meet reguired regulatory treatment/disposal standards prior to
disposal. The Risk Assessment completed for the site, based on data collected after the
completion of all interim response actions, determined that all remaining study areas gualified
for No Further Action.

No federal or state chemical-specific ARARS prevent implementation of the selected alternative.
Soils will be remediated based on health-based cleanup levels determined to be protective of
human health and the environment. Lead-contaminated soils will be remediated to achieve the
health-based soil lead concentration established by EPA (EPA, 1994a) of 400 mg/kg (based on
blood-lead uptake levels in children). Soils contaminated with BAP will be remediated to
achieve the health-based soil concentration of 7 mg/kg. This concentration of 7 mg/kg was
developed using EPA risk assessment guidance for developing preliminary remedial goals (EPA,
1991), referred to as remedial goal options (RGOs) by EPA Region IV. The RGO of 7 mg/kg was
based on a future residential exposure using standard default exposure assumptions.

No location-specific ARARS prevent the use of the selected alternative. All activities
associated with implementing this alternative will be conducted away from sensitive environments
(i.e., river or 100-year floodplain).

The following action-specific ARARS will be met with implementation of this alternative:

• Incinerator ash will be routinely tested for destruction of explosives, as reguired by

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RCRA (40 CFR Part 264: Standards for Owners and Operators of Hazardous Waste Treatment,
Storage, and Disposal Facilities) and the State of Alabama (AAC Chapter
335-14-5.15(4) (a)l: Performance Standards for Incinerators).
• Solidified/stabilized material (if required) will be disposed of onsite in Area B in
accordance with RCRA (40 CFR Part 264: Standards for Owners and Operators of Hazardous
Waste Treatment, Storage, and Disposal Facilities) and the State of Alabama (Code of
Alabama, Title 22, Chapter 27: Alabama Solid Waste Act and Alabama Administrative Code
Chapters 13-1 through 13-7: Alabama Solid Waste Management Regulations).
• Workers will be provided with PPE during all phases of the selected remedy, in compliance
with OSHA (29 USC ss. 651-678). Adequate protection will be provided to the community by
reducing risks posed by air emissions from the thermal treatment unit and reducing dust
potentially generated during material excavation and handling activities.

If the excavated soils are determined to be a hazardous waste, the following action-specific
ARARS would be applicable:

10.3.3 Cost Effectiveness

The selected remedies for soils in Study Areas 13 and 14 within Area A have been determined to
provide overall effectiveness proportionate to its costs.

The Risk Assessment completed for the site, based on data collected after the completion of all
interim response actions, determined that all remaining study areas qualified for No Further
Action.

10.3.4 Use of Permanent Solutions and Alternative Treatment Technologies or Resource
Recovery Technologies to the Maximum Extent Practicable

The selected interim action is designed and intended to be a final action for all soils within
Area A. As such, the alternative meets the statutory requirements to use permanent solutions
and treatment technologies to the maximum extent practicable to achieve remediation goals at
only these two study areas. The criteria used in selecting the alternative include:

• Short-term Effectiveness--The selected alternative does not involve off-facility
transportation of contaminated soils, thereby eliminating the risks to the community due
to spillage and dust emissions. The community, workers, and environment will be
protected during remedial actions by implementing appropriate protective measures.
• Long-Term Effectiveness, and Permanence--The selected alternative provides for remediation
of contaminated soils from Study Areas 13 and 14 within Area A. Direct exposure pathways
would be eliminated.
• Reduction of Contaminant MTV—Contaminant mobility would be significantly decreased due
disposal and solidification of the soils. Contaminant toxicity and soil volume would be
reduced upon treatment.
• Implementability--Required labor, equipment, and materials are available from various
suppliers near ALAAP. Treatment of contaminated soil will not require any additional
special equipment or system mobilization since these components will already be in place.

• Cost—The alternatives selected are the most cost effective available.

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The preferred alternatives were selected based on the cost of implementation. Several
alternatives screened were effective and permanent, each reducing contaminant MTV. Screened
alternatives which were considered final options were each easily implementable. When these
factors were weighed, the lower cost alternatives were selected as the preferred alternatives.

The Risk Assessment completed for the site, based on data collected after the completion of all
interim response actions, determined that all remaining study areas qualified for No Further
Action.

10.3.5 Preference for Treatment as a Principal Element

The selected action uses treatment for the soils of Study Areas 13 and 14 within Area A. The
Risk Assessment completed for the site, based on data collected after the completion of all
interim response actions, determined that all remaining study areas qualified for No Further
Action.

11.0 Documentation of Significant Changes

The selected alternatives (Alternative 13-6 and 14-3) are the preferred alternatives presented
in the Proposed Plan.

12.0 References

Environmental Science & Engineering, Inc. (ESE). 1981. Environmental Survey of Alabama
Army Ammunition Plant. Prepared for U.S. Army Toxic and Hazardous Materials
Agency (USATHAMA), Aberdeen Proving Ground, MD. Gainesville, FL.

Environmental Science & Engineering, Inc. (ESE). 1986. Alabama Army Ammunition Plant
Endangerment Assessment. Prepared for U.S. Army Toxic and Hazardous Materials
Agency (USATHAMA), Aberdeen Proving Ground, MD. Gainesville, FL.

Environmental Science & Engineering, Inc. (ESE). 1990. Supplemental Remedial
Investigation/Feasibility Study for Area B, Alabama Army Ammunition Plant
Endangerment Assessment. Prepared for U.S. Army Toxic and Hazardous Materials
Agency (USATHAMA), Aberdeen Proving Ground, MD. Gainesville, FL.

Environmental Science & Engineering, Inc. (ESE). 1995. Supplemental Remedial
Investigation for Soils/Feasibility Study for Area A, Alabama Army Ammunition Plant
Final Remedial Investigation. Prepared for U.S. Army Environmental Center (USAEC),
Aberdeen Proving Ground, MD. Gainesville, FL.

Environmental Science & Engineering, Inc. (ESE). 1996. Final Proposed Plan for Area A.
Remedial Action of Contaminated Soils at the Alabama Army Ammunition Plant.
August 1996. Prepared for U.S. Army Environmental Center (USAEC).

Integrated Risk Information System (IRIS). 1995. U.S. Environmental Protection Agency
(EPA). Micromedex TOMES PLUS(R) System CD/ROM, Version 25, Expires 7/31/95.
Managed by Micromedex, Inc., Denver, CO.

Oak Ridge National Laboratory (ORNL). 1986. A Review and Analysis of Parameters for
Assessing Transport of Environmentally Released Radionuclides through Agriculture.
Prepared for U.S. Department of Energy. Health and Safety Research Division, Oak
Ridge, TN. ORNL-5786.

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Rosenblatt, D.H. and Small, M.J. 1981. Preliminary Pollutant Limit Values for AAA.P.
Technical Report 8105, AD A104203. USAMBRDL, Fort Detrick, Frederick, MD.

Shaw, C.E., Jr. 1970. Age and Stratigraphic Relations of the Talladega Slate: Evidence of
Pre-middleordovivian Tectonism in Central Alabama. Southeastern Geology 11:253-267.

Shaw, C.E., Jr. 1973. Stratigraphy Structure and Tectonics of Rocks Adjacent to the
Piedmont Physiographic Front in Talladega County, Alabama. In: Talladega
Metamorphic Front—A Guidebook to the Eleventh Annual Field Trip of the Alabama
Geological Society. Carrington, T.J., Ed. Alabama Geological Society.

U.S. Environmental Protection Agency (EPA) . 1988. Review of Ecological Risk Assessment
Methods. Prepared by ICF Inc. Washington, DC. EPA 230-10-88-041.

U.S. Environmental Protection Agency (EPA). 1989a. Risk Assessment Guidance for
Superfund (RAGS). Volume 1: Human Health Evaluation Manual, Part A. Office of
Emergency and Remedial Response, Washington, DC. EPA/540/1-89/002.

U.S. Environmental Protection Agency (EPA). 1989b. Drinking Water Health Advisory for
1,2,4-Trichlorobenzene. Office of Water, Washington, DC.

U.S. Environmental Protection Agency (EPA) . 1991. Risk Assessment Guidance for
Superfund (RAGS). Volume 1: Human Health Evaluation Manual, Supplemental
Guidance (Standard Default Exposure Factors). Interim Final. Office of Emergency and
Remedial Response, Washington, DC. OSWER Directive 9285.6-03.

U.S. Environmental Protection Agency (EPA). 1994a. Health Effects Assessment Summary
Tables (HEAST). Annual Update FY 1994. Office of Research and Development and
Office of Emergency and Remedial Response, Washington, DC. EPA 540/R-94/020.
NTIS No. PB94-921199.

U.S. Environmental Protection Agency (EPA). 1995. Risk-Based Concentration Table,
January - June 1995. Technical Support Section, Region III, Philadelphia, PA. March 7, 1995.

Wentsel, R.S. et al. 1994. Procedural Guidelines for Ecological Risk Assessments at U.S.
Army Sites. Volume 1. U.S. Army Edgewood Research, Development and Engineering
Center, Aberdeen Proving Ground, MD.

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                                Responsiveness Summary

1.0  Overview

The public reaction to the selected final remedy is primarily acceptance.  All public comments
have been addressed, and the public appears to have no concern about implementing the selected
remedy.  Continued community relations activities will be held to maintain public awareness of
the status of remedial activities at ALAAP.

2.0  Background On Community Involvement

General community interest in the ALAAP site has historically not been great.  Since the site
was declared excess to Army needs in 1973, more interest has come from private groups or
industry hoping to develop portions of the site.  The southern part of the site (i.e.,  the
former nitrocellulose manufacturing area) was sold to the Kimberly Clark Corporation in the late
1970s, and a paper products plant was constructed.  In the mid-1980s, in response to interest in
purchasing the eastern part of ALAAP (Area A),  this section was remediated by the Army and the
contaminated soil was stockpiled in the western portion of ALAAP (Area 13),  creating the
Stockpile Soils Area OU.

In 1990, EPA indicated that additional investigations were reguired at Area A to ensure that no
residual contamination remained following the initial remedial actions.  Area A was conveyed to
private buyers in August 1990, with the provision that additional investigations and any
reguired cleanups would be performed by the Army.

In 1991, a supplemental RI was begun to verify the effectiveness of the completed remedial
actions in Area A.  The supplemental RI initially determined that soils at two study areas
within Area A (Study Areas 12 and 30) continued to contain lead and explosives at unacceptable
concentrations.   The supplemental RI/FS concluded that approximately 2,200 yd3 of lead-
contaminated soil from Study Area 12 and approximately 5 yd3 of explosives-contaminated soil
from Study Area 30 reguired further remediation.

A ROD for the Stockpile Soils OU was issued in December 1991 and recommended incineration
as the preferred alternative.  The incineration of the Stockpile Soils began in May 1994 and was
complete in August 1994.

An interim ROD for the Area A Soil OU  (Study Areas 12 and 30) was submitted in April 1994.
During the latter half of 1994, Study Area 12 soils (2,179 yd3) were excavated, stabilized, and
placed on the onsite backfill area in Area B.  Explosives-contaminated soils from Study Area 30
(5 yd3) were excavated, incinerated, and placed in the onsite backfill area in Area B.

Notice of the public comment period and meeting for the Area A Final Proposed Plan was placed
in two local newspapers on August 15 and September 10, 1996, and the public comment period
extended from August 16 through September 15, 1996.  No written public comments were
received.  The public meeting was held on September 10, 1996, at the Central Alabama
Community College, located about 5 miles from the ALAAP site.  The guestions asked were
mainly to obtain more detailed information on the identified contamination and the proposed
remedy.

3.0  Summary of Public Comment and Agency Response

At the public meeting held on September 10, 1996, the public was given the opportunity to
comment and ask guestions about the Proposed Plan.  All guestions were addressed at the meeting.
A transcript of the meeting is available in the Record Archive at the Earle A. Rainwater

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Memorial Library, Childersburg, Alabama.

4.0  Remaining Concerns

All of the public comments have been adequately addressed.  The public appears to have no
concerns about implementing the selected remedy.

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Table 1.  ALAAP STUDY AREAS
          Study Area                    Description
             11            Magazine Area
             12            Old Burning Ground
             13            Small Arms Ballistics Range
             14            Cannon Range
             15            Old Well
             17            Propellant Shipping Area (Eastern Portion)
             29            Rubble Pile
             30            New Trench Area
             31            Disposal Area
             32            No. 2 Rubble Pile
             33            Henningburg Area
             34            229 Area

          Source: ESE, 1994

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Table 2.   Summary of Chemicals of Potential Concern  (COPCs) at AAAP Area A  (Page 1 of 3)

                                      Study Area 11     Study Area 12     Study Area 13     Study Area 14
Chemicals of Potential Concern        GW  SE  SO  SW    GW  SE  SO  SW    GW  SE  SO  SW    GW  SE  SO  SW

Volatile Organic Compounds  (VOCs)
  Acetone                                               GW
  Bromomethane                            SE
  Chloroform
  Methyl butyl ketone                             SW
  Methylene chloride
  Methyl isobutyl ketone
  Tetrachloroethane, 1,1,2,2-             SE
  Trichloroethene
  Trichlorofluoromethane                  SE      SW

Semivolatile Organic Compounds (SVOCs)
  Benzo(b)naphtho(1,2-D)thiophene                                             SE  SO
  Bis(2-ethylhexyl)phthalate          GW  SE  SO  SW    GW      SO        GW  SE  SO                SO
  Carbazole                                                                       SO
  Dibenzofuran                                                                    SO
  Diethyl phthalate                                                           SE  SO
  Di-n-butyl phthalate                        SO                SO            SE  SO                SO
  Trichlorobenzene, 1,2,4-

-------
Polycyclic Aromatic Hydrocarbons  (PAHs)
  Acenaphthene
  Acenaphthylene                              SO
  Anthracene                                  SO
  Benz(a)anthracene                           SO
  Benzo(a)pyrene                              SO
  Benzo(b)fluoranthene                        SO
  Benzo(ghi)perylene                          SO
  Benzo(k)fluoranthene                        SO
  Chrysene
  Fluoranthene                                SO
  Fluorene
  Indeno(1,2,3-cd)pyrene                      SO
  Naphthalene                                 SO
  Phenanthrene                                SO
  Pyrene                                      SO

Nitroaromatic Chemicals
  Dinitrobenzene, m-
  Dinitrotoluene, 2,4-
  Dinitrotoluene, 2,6-
  Nitrosodiphenylamine, N-
  Trinitrobenzene, 1,3,5-
  Trinitrotoluene, 2,4,6-
                  GW
                  GW
                  GW
                          SO
                          SO
                      SO
                          SO
                          SO
                        GW
                        GW
                        GW
                                        SO

                                        SO
                                        SO
                                        SO
                                        SO
                                        SO
                                        SO
                                        SO
                                        SO
                                        SO
                                        so
                                        so
                                        so
                                        so
                                        SE  SO
                                                          so
Inorganic Chemicals
  Aluminum
  Arsenic
  Barium
  Beryllium
  Cadmium
  Chromium
  Cobalt
  Copper
  Iron
  Lead
  Manganese
  Mercury
  Nickel
  Thallium
  Vanadium
GW
GW
GW
GW
GW
GW
GW
GW
GW
GW

GW
    SE
    SE
    SE
        SO
        SO
    SE SO
SE
SE
SE
SE
SE
SE
SE
    SO
        SW
        SW
        SW
SW

SW
SW
GW
GW
GW
GW
GW
GW
GW
GW
GW
GW
GW
GW
GW
SO


SO

SO

SO

SO
SO
                                              SO
GW

GW

GW
GW
GW
GW
GW
GW
GW
GW
GW

GW
                                    SE
                                            SO
                                        SO
                                        SO
                                    SW
SO

SO


SO

-------
Table 2.   Summary of Chemicals of Potential Concern  (COPCs) at AAAP Area A  (Page 2 of 3)

                                      Study Area 15     Study Area 17     Study Area 29     Study Area 30
Chemicals of Potential Concern        GW  SE  SO  SW    GW  SE  SO  SW    GW  SE  SO  SW    GW  SE  SO  SW

Volatile Organic Compounds  (VOCs)
  Acetone                             GW
  Bromomethane
  Chloroform
  Methyl butyl ketone
  Methylene chloride                  GW
  Methyl isobutyl ketone              GW
  Tetrachloroethane, 1,1,2,2-
  Trichloroethene
  Trichlorofluoromethane                                        SO                SO                SO

Semivolatile Organic Compounds (SVOCs)
  Benzo(b)naphtho(1,2-D)thiophene
  Bis(2-ethylhexyl)phthalate          GW                        SO
  Carbazole
  Dibenzofuran
  Diethyl phthalate
  Di-n-butyl phthalate                                          SO                SO
  Trichlorobenzene, 1,2,4-

-------
Polycyclic Aromatic Hydrocarbons  (PAHs)
  Acenaphthene
  Acenaphthylene
  Anthracene
  Benz(a)anthracene
  Benzo(a)pyrene
  Benzo(b)fluoranthene
  Benzo(ghi)perylene
  Benzo(k)fluoranthene
  Chrysene
  Fluoranthene
  Fluorene
  Indeno(1,2,3-cd)pyrene
  Naphthalene
  Phenanthrene
  Pyrene

Nitroaromatic Chemicals
  Dinitrobenzene, m-
  Dinitrotoluene, 2,4-
  Dinitrotoluene, 2,6-
  Nitrosodiphenylamine, N-
  Trinitrobenzene, 1,3,5-
  Trinitrotoluene, 2,4,6-
Inorganic Chemicals
  Aluminum
  Arsenic
  Barium
  Beryllium
  Cadmium
  Chromium
  Cobalt
  Copper
  Iron
  Lead
  Manganese
  Mercury
  Nickel
  Thallium
  Vanadium
GW
GW
GW
GW

GW

GW
GW

GW

GW
                          SO
                          SO
                          SO
                                    GW
                                                              SO
                                                              SO
SO

SO
SO
SO

SO


SO
GW

GW
GW
                          SO
                          SO
                          SO

                          SO
                                    SO

-------
Table 2.   Summary of Chemicals of Potential Concern  (COPCs) at AAAP Area A  (Page 3 of 3)

                                      Study Area 31     Study Area 32     Study Area 33     Study Area 34       A/B
DIVIDE
Chemicals of Potential Concern        GW  SE  SO  SW    GW  SE  SO  SW    GW  SE  SO  SW    GW  SE  SO  SW    GW  SE  SO  SW

Volatile Organic Compounds  (VOCs)
  Acetone
  Bromomethane
  Chloroform                                                                                GW                GW
  Methyl butyl ketone
  Methylene chloride
  Methyl isobutyl ketone
  Tetrachloroethane, 1,1,2,2-
  Trichloroethene                                                                                             GW
  Trichlorofluoromethane                      SO                SO                SO                SO

Semivolatile Organic Compounds (SVOCs)
  Benzo(b)naphtho(1,2-D)thiophene
  Bis(2-ethylhexyl)phthalate                                    SO                SO        GW      SO        GW
  Carbazole
  Dibenzofuran
  Diethyl phthalate
  Di-n-butyl phthalate                                          SO
  Trichlorobenzene, 1,2,4-                                                        SO

-------
Polycyclic Aromatic Hydrocarbons  (PAHs)
  Acenaphthene
  Acenaphthylene
  Anthracene
  Benz(a)anthracene
  Benzo(a)pyrene
  Benzo(b)fluoranthene
  Benzo(ghi)perylene
  Benzo(k)fluoranthene
  Chrysene
  Fluoranthene
  Fluorene
  Indeno(1,2,3-cd)pyrene
  Naphthalene
  Phenanthrene
  Pyrene

Nitroaromatic Chemicals
  Dinitrobenzene, m-
  Dinitrotoluene, 2,4-                                  GW
  Dinitrotoluene, 2,6-
  Nitrosodiphenylamine, N-
  Trinitrobenzene, 1,3,5-
  Trinitrotoluene, 2,4,6-

-------
Inorganic Chemicals
  Aluminum
  Arsenic
  Barium
  Beryllium
  Cadmium
  Chromium
  Cobalt
  Copper
  Iron
  Lead
  Manganese
  Mercury
  Nickel
  Thallium
  Vanadium
          GW

          GW
                  SO
SO

SO

SO


SO
GW
                                                                SO
GW

GW
GW

GW
GW
GW
GW
GW
GW
GW
GW

GW
GW

GW
GW

GW

GW
GW
GW
GW

GW

GW
Note:
  GW = groundwater
  SE = sediment
  SO = soil
  SW = surface water
Source:  ESE (1995)

-------
Table 3.   Chronic Oral and Inhalation RfDs for the COPCs at ALAAP Area A  (Page 1 of 4)

Chemical                         Oral RfD  (UF)*        Oral Target Organ/System        Inhal RfD  (UF)**
IOCS
  Aluminum
  Arsenic
  Barium
  Beryllium
  Cadmium (aqueous matrix)
  Chromium,  total 11
  Cobalt
  Copper
  Iron
  Lead
  Manganese (agueous matrix)
  Manganese (solid matrix)
  Mercury
  Nickel
  Selenium
  Silver
  Thallium
  Vanadium
  Zinc

Munitions/Nitroaromatics
  Dinitrobenzene, 1,3-
  Dinitrotoluene, 2,4-
  Dinitrotoluene, 2,6-
  Nitrosodiphenylamine, N-
  Trinitrobenzene, 1,3,5-
  Trinitrotoluene, 2,4,6-
l.OE+00
3.0E-04
7.0E-02
5.0E-03
5.0E-04
5.0E-03
6.0E-02
3.7E-02
— 14
5.0E-03
1.4E-01
3.0E-04
2.0F-02
5.0E-03
5.0E-03
8.0E-05
7.90E-03
3.0E-01
l.OE-04
2.0E-03
l.OE-03
5.0E-02
5.0E-05
5.0E-04
## (na)
(3)
(3)
(100)
(10)
(500)
** (na)
13 (2)

(1)
(1)
# (1,000)
15 (300)
(3)
16 (3)
17 (3,000)
# (100)
(3)
(3,000)
(100)
# (3,000)
Nl (100)
(10,000)
(1,000)
na
Skin
Cardiovascular
Decreased body weight
NOAEL
NOAEL
na
Gastrointestinal
CNS
CNS
Kidney
Whole body, major organs
Whole body
Skin
Blood, liver
na
Blood
Spleen
CNS, blood
CNS, blood, kidney
Bladder
Spleen
Liver
1.4E-04 # (1,000)
nd 12
                                                        Inhal Target Organ/System
Fetotoxicity
1.4E-05 (1,000)
8.6E-05 # (30)
CNS
CNS

-------
Table 3.   Chronic Oral and Inhalation RfDs for  the COPCs  at ALAAP Area A (Page 2 of 4)

Chemical                            Oral RfD  (UF)*         Oral  Target  Organ/System
PAHs
  Acenaphthene
  Acenaphthylene
  Anthracene
  Benz(a)anthracene
  Benzo(b)fluoranthene
  Benzo(b)naphtho[1,2-D]thiophene
  Benzo(k)fluoranthene
  Benzo(ghi)perylene
  Benzo(a)pyrene
  Chrysene
  Fluoranthene
  Fluorene
  Indeno(1,2,3-cd)pyrene
  Naphthalene
  Phenanthrene
  Pyrene

SVOCS, misc.
  Bis(2-ethylhexyl) phthalate
  Carbazole
  Di-n-butyl phthalate
  Dibenzofuran
  Diethyl phthalate
  Trichlorobenzene,  1,2,4-
                                                       Inhal RfD  (UF) '
                                                          Inhal  Target  Organ/System
6.
3.
3.
3.
3.
3.
3.
3.
3.
3.
4.
4.
3.
4.
3.
3.
, OE-02
, OE-02
. OE-01
, OE-02
, OE-02
, OE-02
, OE-02
, OE-02
, OE-02
, OE-02
, OE-02
, OE-02
, OE-02
, OE-02
, OE-02
, OE-02
(3,
HI
(3,
HI
HI
HI
HI
HI
HI
HI
(3,
(3,
HI
(1,
HI
(3,
000)
(3,000)
000)
(3,000)
(3,000)
(3,000)
(3,000)
(3,000)
(3,000)
(3,000)
000)
000)
(3,000)
000)
(3,000)
000)
Liver
Kidney
NOAEL
Kidney
Kidney
Kidney
Kidney
Kidney
Kidney
Kidney
Kidney, liver, blood
Blood
Kidney
NOAEL
Kidney
Kidney
 2.OE-02  (1,000)
 5.OE-02  SI  (100,000)
 1.OE-01  (1,000)
 4.0E-03  ##  (na)
B.OE-01  (1,000)
 1.OE-02  (1,000)
 Liver, kidney
 na
 Whole body
 na
Whole body
 Adrenal
5.7E-02 # (1,000)
Liver
VOCs, misc.
  Acetone
  Bromomethane
  Chloroform
 1.OE-01  (1,000)
 1.4E-03  (1,000)
 1.OE-02  (1,000)
 Liver, kidney
 Forestomach, kidney
 Liver
1.4E-03 (100)
Heart, gastrointestinal

-------
Table 3.   Chronic Oral and Inhalation RfDs for the COPCs at ALAAP Area A  (Page 3 of 4)

Chemical                            Oral RfD  (UF)*        Oral Target Organ/System
VOCs, misc., cont.
  Methylene chloride
  Methyl butyl ketone
  Methyl isobutyl ketone
  Tetrachloroethane, 1,1,2,2-
  Trichloroethene
  Trichlorofluoromethane
6.0E-02 (100)
2.6E-02 VI
8.0E-02 # (1,000)
3.2E-03 V2 (100,000)
6.0e-03 ## (na)
3.0E-01 (1,000)
Liver
na
Kidney, liver
Liver
Liver
Whole body
Inhal RfD (UF)**


8.6E-01 # (100)

2.0E-02 # (1,000)


2.0E-01 # (10,000)
Inhal Target Organ/System


Liver

Kidney,  liver


Kidney,  lungs
Note:              RfD = reference dose  [mg/kg/d].
                    UF = uncertainty factor.
                    MF = modifying factor.
                 inhal = inhalation.
                    na = not applicable/unknown.
                    nd = not determined.
                   MCL = EPA maximum contaminant  level.
                 LOAEL = lowest-observed-adverse-effect level.
                 NOAEL = no-observed-adverse-effect level.
                 LD 50 = dose resulting in death  in 50 percent of a study population.
                   CNS = central nervous system.
             mg/kg/day = milligrams per kilogram  per day.
                  mg/L = milligrams per liter.
                  Ig/L = micrograms per liter.
                 L/day = liters per day.

    (HI)  No RfD is available for this PAH; the lowest non-naphthalene value  (pyrene) is used for  comparison,  only.
    (II)  All values are for hexavalent chromium,  a less conservative oral RfD of  l.OE+00 mg/kg/day  for  trivalent  chromium is  also  available.
    (12)  Inhalation RfD for chromium has been withdrawn from IRIS pending further EPA review.
    (13)  Oral RfD for copper based on the MCL of  1.3 mg/L  (56 FR 26460) and  assumes that a healthy  70 kilogram adult  consumes 2  L/day water.

-------
Table 3.  Chronic Oral and Inhalation RfDs for the COPCs at ALAAP Area A  (Continued, Page 4 of 4)

  (14)   EPA prefers to use a biokinetic uptake model to evaluate lead exposure rather than the reference dose method  (EPA,  1991e).
  (15)   Oral RfD for soluble nickel salts.
  (16)   Oral RfD for silver based on aesthetic endpoint (argyria).
  (17)   No oral RfD is available for metallic thallium; the listed value for thallium chloride is from HEAST  (EPA,  1994).
  (Nl)   Oral RfD for N-nitrosodiphenylamine based on a chronic oral LOAEL for rats of 50 mg/kg/day  (ATSDR, 1987) and  an  uncertainty  factor  of  1,000
        (10 for sensitive human subpopulations, 10 for animal-to-human extrapolation, and 10 for LOAEL-to-NOAEL extrapolation).
  (SI)   Oral RfD for carbazole based on an acute oral LD 50 for rats of >5,000 mg/kg  (HSDB, 1995),  an uncertainty factor of 10,000  (10  for  sensitive
        human subpopulations, 10 for animal-to-human extrapolation, 10 for acute-to-chronic extrapolation, and 10 for LD 50-to-NOAEL extrapolation),  and
        a modifying factor of 10 (accounts for the lethal endpoint of the study).
  (VI)   Oral RfD for methyl butyl ketone based on an acute oral LD 50 for rats of 2,590 mg/kg/day  (RTECS, 1995), an uncertainty  factor  of 10,000  (10  for
        sensitive human subpopulations, 10 for animal-to-human extrapolation, 10 for acute-to-chronic extrapolation,  and 10 for  LD 50-to-NOAEL
        extrapolation),  and a modifying factor of 10 (accounts for the lethal endpoint of the study).
  (V2)   Oral RfD for 1,1,2,2-tetrachloroethane based on an interim oral LOAEL for rats of 3.2 mg/kg/day  (ATSDR, 1988) and an uncertainty factor of
        1,000 (10 for sensitive human subpopulations, 10 for animal-to-human extrapolation, and 10  for LOAEL-to-NOAEL extrapolation).

  *A11 oral RfDs are available in IRIS  (1995), unless otherwise noted.
  **RfDs are based on the inhalation RfC available in IRIS (1995) and assume that a healthy 70-kilogram adult inhales 20 m3/day  air,  unless
  otherwise noted.
  #Value available in HEAST, 1994 Annual Update (EPA, 1994) .
  ##Provisional value available from EPA's Environmental Criteria and Assessment Office  (ECAO) and  presented in EPA Region  Ill's  Risk-Based
  Concentration Table, January - June 1995 (EPA, 1995).

  Source:   ESE.

-------
Table 4. CSFs and WoEs for the Known/Potential Carcinogenic COPCs at ALAAP Area A,  (Page  1  of  2)

Chemical                          Oral CSF*     Oral WoE*     Inhal CSF**      Inhal WoE*
IOCS
  Arsenic
  Beryllium
  Chromium, total HI
  Lead
  Nickel

Munitions/Nitroaromatics
  Dinitrotoluene, 2,4-
  Dinitrotoluene, 2,6-
  Nitrosodiphenylamine, N-
  Trinitrotoluene, 2,4,6-

PAHs
  Benz(a)anthracene
  Benzo(b)fluoranthene
  Benzo(k)fluoranthene
  Benzo(a)pyrene
  Chrysene
  Indeno(1,2,3-cd)pyrene

SVOCS, misc.
  Bis(2-ethylhexyl)phthalate

VOCS, misc.
  Chloroform
  Methylene chloride
  Tetrachloroethane, 1,1,2,2-
  Trichloroethene
1
4



6
6
4
3
7
7
7
7
7
7
.5E+00
.3E+00
nc
nd 12
nc
. 8E-01
. 8E-01
. 9E-03
. OE-02
.3E-01
.3E-01
.3E-02
.3E+00
.3E-03
.3E-01





Nl
Nl


HI
HI
HI

HI
HI
A
B2

B2

B2
B2
B2
C
B2
B2
B2
B2
B2
B2
1
8
4.

8




6
6
6
6
6
6
.5E+01
.4E+00
1E+01
nd 12
.4E-01
nd N2
nd N2
nd N2
nd N3
.1E-01
.1E-01
.1E-02
.1E+00
.1E-03
.1E-01
#
#
#

13
,#
,#
,#

HI
HI
HI

HI
HI
A
B2
A
B2
A
B2
B2
B2
C
B2
B2
B2
B2
B2
B2
1.4E-02           B2
6.1E-03           B2
7.5E-03           B2
2.0E-01           C
1.1E-02 VI,##     B2
                               nd SI
8.1E-02 #
1.6E-03
2.0E-01
6.0E-03 VI,##
                                                  B2
B2
B2
C
B2
Note:                 CSF = cancer slope factor  [(mg/kg/day)-1].
                      WoE = weight of evidence for ranking  as  a human carcinogen.
                    inhal = inhalation.
                       nd = not determined.
                mg/kg/day = milligrams per kilogram per day.
                     mg/L = milligrams per liter.
                     Ig/L = micrograms per liter.
                    L/day = liters per day.

(HI)  CSF for this potentially carcinogenic PAH  is an interim  value from EPA ECAO  and  listed  in
       EPA Region Ill's Risk-Based Concentration Table, January to June 1995 (EPA, 1995).  The
       value is based on the CSF for benzo(a)pyrene and the following Toxicity Eguivalency
       Factors: benz(a)anthracene, 0.1; benzo(b)fluoranthene,   0.1; benzo(k)fluoranthene, 0.01;
       chrysene, 0.001;  dibenz(ah)anthracene,  1.0; and indeno(1,2,3-cd)pyrene,  0.1.

-------
Table 4.  CSFs and WoEs for the Known/Potential Carcinogenic COPCs at ALAAP Area A
         (Continued, Page 2 of. 2)

(II)  All values are for hexavalent chromium; a less conservative oral RfD of 1E+00 mg/kg/day
      for trivalent chromium is also available.
(12)  Although EPA has classified lead as a Group B2 suspect human carcinogen via ingestion and
      inhalation, no CSF has been developed for either of these exposure pathways.
(13)  Inhalation CSF for nickel refinery dust.
(Nl)  No oral CSF is available for this munitions compound alone; the listed value is for
      2,4-dinitrotoluene/2,6-dinitrotoluene mixture.
(N2)  Although EPA has classified this chemical as a Group B2 suspect human carcinogen via
      inhalation, no CSF has been developed for this exposure pathway.
(N3)  Although EPA has classified this chemical as a Group C possible human carcinogen via
      inhalation,  no CSF has been developed for this exposure pathway.
(SI)  Although EPA has classified, this SVOC as a Group B2 suspect human carcinogen via
      inhalation, no CSF has been developed for this exposure pathway.
(VI)  CSFs and WoEs for this VOC have been withdrawn from IRIS pending further review.

*A11 oral CSFs and WoEs are available in IRIS  (1995), unless otherwise noted.
**Inhalation CSFs are based on the inhalation UR available in IRIS (1995) and assume that a
healthy 70-kilogram adult inhales 20 m3/day air, unless otherwise noted.
#Value available in HEAST, 1994 Annual Update  (EPA, 1994).
##Provisional value available from EPA' s Environmental Criteria and Assessment Office (ECAO) and
presented in EPA Region Ill's Risk-Based Concentration Table, January - June 1995 (EPA,  1995).

Source:  ESE.

-------
Table 5.  Summary of Media and Chemicals of Concern  (COCs) Exceeding Human  Health Risks  of 10-6 and Hazard  Indices (His)  of 0.1 (Page 1 of 5)
                                                     Noncarcinogenic
                                                    Hazard  Index  (HI)
                                      Carcinogenic
Area Scenario Media
11 Future Groundwater
Resident
Soil
Surface
Water
Future Groundwater
Worker
Soil
Hunter Soil
12 Future Groundwater
Resident
Soil
Future Groundwater
Worker
Soil
Hunter Soil
13 Future Groundwater
Risk Adult
2 x 10-6 54
2 x 10-5 <0.1
1 x 10-6 0.2
<1 x 10-6 19
5 x 10-6 <0.1
1 x 10-6 <0.1
3 x 10-4 6
9 x 10-6 <0.1
7 x 10-5 2.1
4 x 10-6 <0.1
1 x 10-6 <0.1
3 x 10-6 66
Child
99 C:
NC:
0.3 C:
NC:
0.6 C:
NC:
NA c NC:
NA C:
NA C:
11 C:
NC:
0.2 C:
NC:
NA C:
NC:
NA C:
NA C:
120 C:
Chemicals of Concern (COCs) a
B2EHP
Mn, Al, V, Co, Cr, Cu, Ni, Pb b
Be, BAP, Cr
No individual chemicals exceed 0.1
As
Mn
Mn, Al, V, Pb b
Cr, Be
No individual chemicals exceed 10-6
Be, As, B2EHP, 26DNT, 24DNT
Mn, Cd, As, Al, Cr d
Cr
Cr d
Be, As
Mn
Cr
Cr
B2EHP, 24DNT
Risk
NC (A&C)
C
NC (C)

NC (A)
C
C
NC (A&C)

NC (A)


NC (A&C)
       Resident
NC:  Mn, Cd, Al, Cr, Ba, V, Ni d, Pb b

-------
Table 5.  Summary of Media and Chemicals of Concern (COCs) Exceeding Human Health Risks of 10-6 and Hazard
          Indices (His)  of 0.1 (Page 2 of 5)
                                                     Noncarcinogenic
                                                    Hazard Index (HI)
                                      Carcinogenic
 Area    Scenario       Media           Risk        Adult       Child         Chemicals of Concern (COCs) a
Risk
 13
 14
 15
 17
 29
Future
Resident
(Cont.)
Future
Worker


Hunter
Future
Resident
Future
Worker
Future
Resident
Future
Worker
Future
Resident
Future
Worker
Future
Resident
Soil 2 x 100-4 <0.1 <0.1 C:


Groundwater <1 x 10-6 24 NA NC:

Soil 3 x 10-5 <0.1 NA C:

Soil 7 x 10-6 <0.1 NA C:
Soil 1 x 10-6 <0.1 <0.1 C:
NC:
Soil <1 x 10-6 <0.1 NA NC:

Groundwater 1 x 10-6 11 21 C:
NC:
Groundwater <1 x 10-6 4 NA NC:

Soil 2 x 10-5 <0.1 0.4 C:
NC:
Soil 2 x 10-6 <0.1 NA C:

Groundwater 1 x 10-6 0.6 1.2 C:
NC:
BAP, BBFANT, BAANTR, ICDPYR,
Be , BKFANT

Mn, Cd, Al, Cr, Pb b

BAP, BBFANT, BAANTR, ICDPYR,
Be
BAP
No individual chemicals exceed 10-6
Pb c
Pb f

No individual chemicals exceed 10-6
Mn, Al, Cr d, Ni d, V d
Mn

Be
Al d, Ba d
Be

24DNT
Mn, Al d
C


NC (A)




NC (A&C)

NC(A)

NC (A&C)

NC(A)





NC(C)

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Table 5.  Summary of Media and Chemicals of Concern  (COCs) Exceeding Human Health Risks of 10-6 and Hazard
          Indices (His)  of 0.1 (Page 3 of 5)
                                                     Noncarcinogenic
                                                    Hazard Index  (HI)
                                      Carcinogenic
Area
29
( cont )
30

31

32



34

Scenario Media Risk Adult
Future Groundwater <1 x 10-6 0.2
Worker
Future Soil 6 x 10-6 <0 . 1
Resident
Future Soil 3 x 10-6 <0 . 1
Worker
Future Soil 6 x 10-6 <0 . 1
Resident
Future Soil 3 x 10-6 <0 . 1
Worker
Future Groundwater 1 X 10-6 0.6
Resident
Soil 1 x 10-5 <0.1
Future Groundwater <1 x 10-6 0.2
Worker
Soil 1 x 10-6 <0.1
Future Groundwater 6 x 10-4 42
Resident
Future Groundwater 2 x 10-4 15
Worker
Child
NA NC:
0.2 C:
NC:
NA C:
0.1 C:
NC:
NA C:
1.2 C:
NC:
0.2 C:
NC:
NA NC:
NA C:
76 C:
NC:
NA C:
NC:
Chemicals of Concern (COCs) a
Mn
Cr
135TNB
Cr
Cr
No individual chemicals exceed 0.1
Cr
24DNT
Mn, Al d
Be
V d
Mn
Be
Be, B2EHP, CHCL3
Mn, Al, V, Cr, Ni, Ba d, Cu d, Be d
Be
Mn, Al, V, Cr
Risk
NC (A)




NC (C)



C
NC(A&
C
NC (A)

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Table 5.  Summary of Media and Chemicals of Concern  (COCs) Exceeding Human Health Risks of 10-6 and Hazard
          Indices (His) of 0.1 (Page 4 of 5)
                                                     Noncarcinogenic
                                                    Hazard Index  (HI)
                                      Carcinogenic
 Area    Scenario
 A/B    Future
 Divide Resident

        Future
        Worker
Media           Risk        Adult       Child         Chemicals of Concern  (COCs) a

Groundwater   5 x 10-4        16          28      C:   Be, CHCL3, B2EHP
                                                  NC:  Mn, Al, Ni d, V d, Cr d,  Pb b

Groundwater   1 x 10-4       5.6          NA      C:   Be
                                                  NC:  Mn, Al, Pb b
Risk

C
NC(ASC)

C
NC (A)
Notes:

This table only includes media for scenarios at areas with risks greater than or egual to  (1 x  10-6, with hazard  indices  (His)  0.1,
or where lead was a concern  (see footnotes b, e, and f).
      C = carcinogenic risk
     NC = noncarcinogenic risk
  NC(A) = noncarcinogenic risk to adults
  NC(C) = noncarcinogenic risk to children
NC(ASC) = noncarcinogenic risk to adults and children
 135TNB = 1,3,5-trinitrobenzene
  24DNT = 2,4-dinitrotoluene
  26DNT = 2,6-dinitrotoluene
     Al = aluminum
     As = arsenic
  B2EHP = bis(2-ethylhexyl)phthalate
     Ba = barium
 BAANTR = benz(a)anthracene
    BAP = benzo(a)pyrene
 BBFANT = benzo(b)fluoranthene

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Table 5.  Summary of Media and Chemicals of Concern (COCs) Exceeding Human Health Risks of 10-6 and Hazard
          Indices (His) of 0.1 (Page 5 of 5)

Notes (Continued):

     Be = beryllium
 BKFAMT = benzo(k)fluoranthene
     Cd = cadmium
  CHCL3 = chloroform
     Co = cobalt
     Cr = chromium
     Cu = copper
 ICDPYR = indeno(1,2,3-cd)pyrene
     Mn = manganese
     Ni = nickel
     Pb = lead
      V = vanadium

a Chemicals of concern (COCs) are those analytes with carcinogenic risks exceeding 1 x 10-6 or noncarcinogenic hazard indices  (His)
exceeding 0.1.  Carcinogenic COCs are in descending order from highest risk to lowest risk; noncarcinogenic COCs are in descending
order from highest HI to lowest HI.  The first chemicals listed in the COCs column contributed to over 70% of the risk or over 80%  of
the HI.

b Concentration of lead in groundwater exceeds the U.S. Environmental Protection Agency (EPA) action level of 15 micrograms per liter
(Ig/L).

c NA = not applicable.

d Exceeded HI of 0.1 for children only.  If analyte does not have this footnote, the HI exceeded 0.1 for both adults and children.

e Concentration of lead in soil exceeds the EPA health-based guidance level of 400 milligrams per kilogram (mg/kg) for residential
exposure.

f Concentration of lead in soil exceeds the EPA guidance level of 1,000 mg/kg for worker exposure.

Source:   ESE  (1995)

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Table 6.  Summary of Media and Chemicals  of Concern (COCs)  Exceeding Terrestrial and Aquatic
          Ecological Ecotoxicity Quotients  (EQs)
Area    Scenario

11      Mammal
           (Raccoon)
           (Peromyscus Mouse)
           (Whitetailed Deer)
        Plant
           (Blackberry)
        Aquatic Organism
           (Daphnia)
Media
Soil
Soil
Soil
Soil
Surface Water
Ba (9.9)
Ba (4.9)
Ba (1.6)
V (5.0)
Al (1.3)
Chemical(s) of Concern
[COC(s)]  a and EQs
                 Ba  (9.9), Cr  (1.4),  Pb  (4.3), V (48)
12      Bird
           (Bobwhite)
        Mammal
           (Peromyscus Mouse)
           (Whitetailed Deer)
Soil

Soil
Soil
Ba  (10), Cr  (2.7)

Ba  (3.7), Cr  (1.4), Pb  (1.3)
Ba  (1.2)
14      Mammal
           (Whitetail Deer)
        Plant
           (Slender Bush Clover)
Soil

Soil
Pb  (160)

Pb  (57), Cu  (5.0)
17      Mammal
           (Whitetailed Deer)
        Plant
           (Blackberry)
Soil

Soil
Ba  (4.2)

Al  (430)
30      Bird
           (Bobwhite)
        Mammal
           (Peromyscus Mouse)
Soil

Soil
Cr  (2.0), Cu  (1.2)

Cr  (1.0)
32      Mammal
           (Whitetailed Deer)
        Plant
           (Slender Bush Clover)
Soil

Soil
V  (12)

V  (7.5)
Notes:  a Chemicals of concern  (COCs)  are  those  analytes with ecotoxicity quotients  (EQs)
exceeding 1.
                  Al = aluminum
                  Cr = chromium
                  Cu = copper
                  Pb = lead
                   V = vanadium
Source:  ESE, 1995.

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Table 7.   Uncertainties in the Human Risk Assessment Process

RA Component           Potential for Uncertainty
    Hazard
Identification
Initial section of COCs
Tentatively identified compounds (TICs)
Chemical monitoring data
Current and future land uses
                  * Selection of toxicity values
                  * Factors used in derivation of reference doses (RfDs),  including
   Toxicity         interspecies extrapolation
  Assessment      * Weight-of-evidence for human carcinogenicity
                  * Derivation of carcinogenic slope factors (CSFs)
                  * Extrapolation of less-than-lifetime exposure to lifetime cancer risks
                   Interaction of multiple substances
                  * Selection of site-specific exposure pathways
   Exposure       * Estimation of exposure concentrations without monitoring data
  Assessment      * Estimation of exposure to multiple substances
                  * Estimation of exposure parameters
                  * Use of modeled values for future exposure conditions
     Risk
Characterization

Source:  ESE.
Addition of risks across multiple exposure pathways
Addition of risks from multiple substances

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Table 8.   Uncertainties in the Ecological Risk Assessment Process
ERA Component
            Potential  for Uncertainty
   COPC
Selection
  Chemical monitoring data collected over time,  analyzed by different
  laboratories,  and evaluated using varying guality assurance  methodology
  Presence of tentatively identified compounds  (TICs)
  Current and future land uses
  Lack of site-specific background data
                  * Selection of terrestrial and aguatic indicator species
                  * Selection of site-specific exposure pathways
   Exposure       * Estimation of surface water and sediment concentrations without
  Assessment        monitoring data
                  * Estimation of exposure to multiple substances
                  * Estimation of exposure parameters
   Toxicity
  Assessment
     Risk
Characterization
*  Selection of benchmark values
*  Uncertainty factors  used in derivation of toxicity reference values
  (TRVs),  including interspecies  extrapolation
*  Interaction of multiple substances

*  Evaluation of risks  from multiple exposure pathways
*  Addition of risks from multiple substances
Use of generalized ambient water guality criteria (AWQCs)  and water
  guality standards (WQSs)  to evaluate risks to aguatic life
Source:  ESE.

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                                   Figures

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4WD-FFB

Certified Mail
Return Receipt Requested

Mr. Randy Nida
U.S. Army Industrial Operations Command
Building 390, 4th Floor, NW Wing
AMSID-EQE
Rock Island, Illinois 61299-6000

SUBJ:  Concurrence with Final Record of Decision for Operable Unit 5
       Alabama Army Ammunition Plant (AAAP),  Childersburg, Alabama

Dear Mr. Nida:

   The U.S. Environmental Protection Agency  (EPA) Region IV has reviewed the above referenced
decision document and concurs with the Final Record of Decision (ROD) for Operable Unit 5, Areas
A Soil and Groundwater,  as supported by the Remedial Investigation and Baseline Risk Assessment
Reports.

   The selected remedies ares Alternative 13-6 for Study Area 13,  Alternative 14-3 for Study
Area 14, and No Further Action for all remaining Study Areas and groundwater.  EPA concurs
with the selected remedy as detailed in the ROD.

   This action is protective of human health and the environment,  complies with Federal and
State requirements that are legally applicable or relevant and appropriate to the remedial
action and is cost effective.



cc:    Richard Isaac, U.S. Army Environmental Center
       Kenneth Gray, U.S. Army Corps of Engineers
       C.H. Cox, Alabama Department of Environmental Management

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