Superfund Record of Decision Louisiana Army Ammunition Plant Soil Source OU Doyline LA


                                    EPA/ROD/R06-97/118
                                    1997
EPA Superfund
     Record of Decision:
     LOUISIANA ARMY AMMUNITION PLANT
     EPA ID: LA0213820533
     OU02
     DOYLINE, LA
     03/04/1997

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                                      Final Record of Decision (ROD)  for
                                       Louisiana Army Ammunition Plant
                                           (IiAAP)  Soil/Source)  Area
                                              Operable Unit (OU)
                                                Prepared for:
                                        U.S.  Army Environmental Center
                                      Installation Restoration Division
                                 Aberdeen Proving Ground,  Maryland 21010-5401

                                                 Prepared by:
                                  Environmental Science & Engineering, Inc.
                                             St. Louis, Missouri

                                              September 17,  1996

                                        ESE  Project No. 490-2025-1100

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Louisiana Army Ammunition Plant Soil/Source Operable Unit ROD

DECLARATION

Selected Remedial Alternative for the Soil/Source Operable Unit
Louisiana Army Ammunition Plant
Shreveport, Louisiana

Site Name and Location

This Record of Decision (ROD) has been prepared for the Louisiana Army Ammunition Plant (LAAP)
Soil/Source Operable Unit (OU). Seven study areas are included as part of the Soil/Source OU:
Area P, Burning Ground #5 (BG-5), Landfill #3 (LF-3), Oily Waste Landfarm (OWL), Burning Ground
#8 Landfill (BG-8 Landfill), BG-8 Lagoon, and Manufacturing Area M-4 (M-4) Lagoon. The content
of this ROD is based on recommendations in the U.S. Environmental Protection Agency (USEPA)'s
Interim Final Guidance on Preparing Superfund Decision Documents (USEPA, 1989).

The Army, in consultation with the USEPA and the Louisiana Department of Environmental Quality
(LDEQ), has split the shallow groundwater at the seven study areas into a separate operable
unit. At seven study areas, there are now two operable units: the Soil/Source OU and the
Groundwater OU. This ROD addresses only the Soil/Source OU at the seven study areas. Remedy
selection for the shallow groundwater at LAAP will be addressed at a later date under a separate
ROD. Groundwater will be discussed in this document only with respect to the potential effect
of the constituents in the Soil/Source OU to the guality of the shallow groundwater.

Statement and Basis of Purpose

This ROD presents the selected remedial action for the LAAP Soil/Source OU, chosen in accordance
with the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA),
as amended by the Superfund Amendments and Reauthorization Act of 1996 (SARA), and the National
Oil and Hazardous Substances Pollution Contingency Plan (NCP). This ROD explains the factual and
legal basis for selecting the response actions for the Soil/Source OU. The information
supporting this remedial action decision is contained in the Administrative Record for the
Soil/Source OU.

Description of the Selected Remedy

The selected remedy for the Soil/Source OU is No Further Action for each of the seven study
areas. An Interim Remedial Action (IRA) was conducted at one of the study areas, Area P, from
1987 through 1990, with approval from the USEPA and LDEQ. This action took place during the
performance of the Supplemental Remedial Investigation conducted in 1990 and 1991. The

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                                     Table of Contents

Section                                                                                     Page

1.0 Site Name,  Location,  and Description 	   1
    1.1   LAAP Surface Water 	   1
    1.2   Hydrogeological Summary 	   2

2 . 0 Site History and Enforcement Actions 	   6

3.0 Highlights of Community Participation 	   8

4 . 0 Scope and Role of Response Action 	   9

5 . 0 Summary of Site Characteristics 	  10
    5.1   Area P 	  10
    5.2   BG-8 Landfill/Lagoon 	  11
    5.3   BG-5 	  12
    5.4   LF-3 	  12
    5.5   OWL 	  13
    5.6   M-4 Lagoon 	  13

6.0 Summary or Site Risks 	  15
    6.1   Identification of Constituents of Concern 	  15
    6.2   Exposure Assessment 	  15
    6.3   Toxicity Assessment 	  17
    6.4   Risk Characterization 	  26
    6.5   Ecological Risk Summary 	  35

7.0 Description of the No Further Action Alternative 	  36

8.0 Documentation of Significant Charges 	  38

9. 0 References	  39

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                                        Table of Contents  (continued)
List of Tables
Table 6-1    Chemicals of Concern in Soil by Study Area

Table 6-2    Formulas and Factors Used in the Exposure Pathways Evaluated
             in the BRA

Table 6-3    Formulas and Factors Used in the Exposure Pathways Evaluated
             in the Expanded RA

Table 6-4    Chronic Toxicity Values for Potential Non-carcinogenic Effects of
             the Soil COCs

Table 6-5    Toxicity Values for Potential Carcinogenic Effects of the Soil
             COCs

Table 6-6    BRA Summary - Exposure of Human and Ecological Receptors
             to Soil COCs

Table 6-7    Expanded RA Summary - Exposure of Humans to Soil
             Constituents
Page

  16


  18


  23


  27


  28


  31


  33
             List of Figures

Figure 1-1   Site Locations, Louisiana Army Ammunition Plant
             List of Appendices

Appendix A   Responsiveness Summary

Appendix B   Administrative Record Index

Appendix C   Letters of Support Agency Concurrence

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                                        Table of Contents  (continued)

             List of Acronyms and Abbreviations

BDL          below detection limit
BRA          Baseline Risk Assessment
CERCLA       Comprehensive Environmental Response,  Compensation, and Liability Act
COCs         constituents of concern
CSF          carcinogenic slope factor
DA           Department of the Army
EQ           ecotoxicity quotient
FS           Feasibility Study
HI           hazard index
HMX          High Melting Explosive, cyclotetramethylenetetranitramine,  octahydro-1,3,5,7-
             tetranitro-1,3,5,7-tetrazocine
HQ           hazard quotient
IEUBK        Integrated Exposure Uptake Biokinetic
IOC          Industrial Operations Command
IRA          Interim Remedial Action
LAAP         Louisiana Army Ammunition Plant
LDEQ         Louisiana Department of Environmental Quality
LOAEL        lowest observed adverse effect level
MF           modifying factor
NCP          National Contingency Plan
NOAEL        no observed adverse effect level
OU           Operable Unit
OWL          Oily Waste Landfarm
PCE          tetrachloroethene
RAGS         Risk Assessment Guidance for Superfund
RDX          Research and Development Explosive, cyclonite hexahydro-1,3,5-trinitro-
             1,3,5-triazine
RfDs         reference doses
RI           Remedial Investigation
ROD          Record of Decision
SARA         Superfund Amendments and Reauthorization Act
Tetryl       N-Methyl-N,2,4,6-tetranitroaniline
TRCLE        trichloroethylene
UF           uncertainty factor
USAEC        U.S. Army Environmental Center
USEPA        U.S. Environmental Protection Agency
VOCs         volatile organic compounds

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1.0 Site Name, Location, and Description

Louisiana Army Ammunition Plant (LAAP) is located approximately 22 miles east of Shreveport,
Louisiana, adjacent to the community of Doyline, on State Highway 164. LAAP lies within Bossier
and Webster Parishes and consists of 14,974 acres of land measuring 9 miles east to west and 3
miles north to south. The site is bounded on the north by Interstate 20 and U.S. Highway 80.
Seventy-four acres are administrative and residential land; 2,970 acres are devoted to
production lines and mission support facilities, and 11,930 acres are woodlands. Nearly all
undeveloped areas at LAAP are covered by pines and hardwoods. The area surrounding LAAP is
primarily rural with scattered small towns.

Seven study areas are included as part of the Soil/Source Operable Unit 1 (OU): Area P, Burning
Ground #5 (BG-5), Landfill #3 (LF-3), Oily Waste Landfarm (OWL), Burning Ground #8 Landfill
(BG-8 Landfill), BG-8 Lagoon, and Manufacturing Area M-4 (M-4) Lagoon. The BG-8 Landfill and
BG-8 Lagoon were combined into one study area (BG-8 Landfill/Lagoon) since they are contiguous,
lie on the same hydrogeologic unit, and are similar in types of chemicals present. The seven
study areas of concern are shown on Figure 1-1.

LAAP was added to the National Priorities List (NPL) list in March 1989 due to the potential
risk to human health and the environment posed by Area P. However, the site listing on the NPL
encompasses the entire installation.

1.1 LAAP Surface Water

LAAP is located in the Red River Basin. Surface water within LAAP leaves via two bayous and
two creeks (see Figure 1-1). These waterways are Clark Bayou, which forms the western boundary
of LAAP; Bayou Dorcheat, which forms the eastern boundary of LAAP; Caney Creek, located 1 to 2
miles east of Clark Bayou; and Boone Creek, which drains the central portion of LAAP. An
unnamed ditch originates on LAAP and flows south, then west to join Caney Creek near the
southern LAAP boundary. All of these waterways discharge into Lake Bistineau, located southeast
of LAAP.

Four of the Remedial Investigation (RI) study areas drain into Boone Creek. These are BG-5,
OWL, LF-3, and BG-8 Landfill Lagoon. The two remaining study areas, Area P and M-4 Lagoon,
drain into Caney Creek, which then discharges into Clarke Bayou. The M-4 Lagoon drains directly
to Caney Creek and Area P drains into Caney Creek via the unnamed ditch.

1 Bold indicates words that are defined in the Glossary of Terms located after Section 8.0
of the ROD

1.2 Hydrogeological Summary

Two aguifers are present below the LAAP installation: the Terrace/Sparta Sand aguifer and the
Wilcox-Carrizo Sand aguifer. The closest aguifer to the ground surface at the LAAP installation
is the Terrace/Sparta Sand aguifer, which covers the entire LAAP installation area. This
aguifer is made up of two hydrogeologic units, the Terrace and the Sparta Sand formations.
Because groundwater can flow between the Terrace and Sparta Sand formations in many places, they
are referred to together as the Terrace/Sparta Sand aguifer. The combined Terrace/Sparta Sand
aguifer makes up the shallow groundwater at LAAP. The shallow groundwater discharges to surface
water on LAAP, specifically into Boone and Caney Creeks.

The Terrace portion of the aguifer ranges in thickness from zero (ground surface) to an average
of 50 feet below ground surface at LAAP. The groundwater in the Terrace portion is typically
found within 25 feet of the ground surface. The direction of groundwater flow in the Terrace

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portion is controlled primarily by topography and surface water drainage. LAAP has no water
wells drawing from this aguifer. Although some private home wells in nearby Doyline use the
Terrace portion of the aguifer, the soil/sources at the seven study areas have not affected
these wells. In addition, one of the Village supply wells (located north of LAAP) draws water
from this portion of the aguifer. The soil/sources at the seven study areas have also not
affected this well. There are no known private wells in the Village.

The Sparta Sand portion of the aguifer is found below the Terrace portion only under the eastern
one-half to two-thirds of the LAAP installation. The Sparta Sand portion is found at a depth of
40 to 50 feet below ground surface and ranges in thickness from 100 feet (eastern end of LAAP)
to 0 feet (western end). The direction of groundwater flow in the Sparta Sand portion generally
appears to follow the northeasterly dip of the formation. The Sparta Sand portion is the
principal source of drinking water for the town of Minden, northeast of the plant's eastern
boundary. However, Bayou Dorcheat, which is located between Minden and the plant boundary,
serves as a recharge zone to the Terrace/Sparta Sand aguifer and, therefore, should be a
hydraulic barrier between the installation and Minden (Water Supply Evaluation, Gravel Quarry
Intake, Louisiana Army Ammunition Plant, U.S. Army Corps of Engineers, Fort Worth District, July
1996).

The Cane River formation lies below the Terrace/Sparta Sand aguifer and is considered to be a
confining unit. A confining unit is a geologic unit made up of soils and clays that are so
tight that water travels through it very slowly. Because there is so little water in the Cane
River Formation, it is not an aguifer and cannot be used as a water source. The Cane River
Formation consists of silty clay which turns to shale as depth increases. This type of silty
clay and shale restricts water movement to 10 -7 to 10 -10 centimeters per second. Therefore,
the Cane River formation is an effective barrier to groundwater flow between the Terrace/Sparta
Sand aguifer and the Wilcox-Carrizo Sand aguifer, which lies directly below it. The Cane River
Formation is present below each of the seven LAAP study areas and at the LAAP water supply
wells, but diminishes west of Caney Creek. This formation is encountered at a depth of 30 to 70
feet below ground surface in the vicinity of the LAAP study areas and ranges from less than 50
to 200 feet in thickness. The LAAP water supply wells and the remaining Village supply wells
draw from the Wilcox-Carrizo Sand aguifer. These wells have not been affected by the
soil/source areas on LAAP.

Detailed information concerning the hydrogeology of LAAP is contained in the RI Report.

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Since 1941, seven land tracts of various sizes have been sold, decreasing the size of the
installation by 894 acres to its current size of 14,974 acres. In 1963, approximately 158 acres
were sold to Louisiana Polytechnic Institute and approximately 591 acres were sold to the
Bossier Parish School Board. Both parcels of land were sold with deed restrictions for
educational use only. Other land parcels sold from the installation include property on its
northwest corner currently being used as a rifle range; a portion along the eastern boundary
sold to a sand and gravel company; a 138-acre parcel that is used for hunting; and two small
tracts of land that are used for retail businesses.

Currently, LAAP is a government-owned, contractor-operated industrial installation under
contractual agreement with Thiokol Corporation to manufacture ammunition metal parts and load-
assemble-pack ammunition items. The primary functions of LAAP as an Industrial Operations
Command (IOC) installation are as follows:

• Loading, assembling, and packing of ammunition items;
• Manufacture of ammunition metal parts;
• Operation and maintenance of active facilities in support of current production
operations; and
• Maintenance and/or layaway of standby facilities (including any machinery and
package lines and production eguipment packages received from industry or other
government installations.

The current working population of LAAP is less than 100, which includes military personnel,
contractor personnel, and civil service workers. Historically, the number of workers at the
installation has exceeded 7,000 during high production periods.

A series of investigations and studies have taken place at LAAP to evaluate the potential for
and extent of contamination from waste management activities at the installation. The
investigations addressed in this ROD began with an initial records search in 1978 and ended with
the comprehensive RI performed in 1991. In 1987, with approval from USEPA and LDEQ, the Army
initiated an IRA at Area P.

In addition to the investigations conducted for the seven soil/source areas, there are currently
several other areas at LAAP that are also being investigated. These areas include ten
manufacturing areas, three test areas, and the Groundwater Operable Unit. These areas are not
discussed in this ROD.

As part of the studies conducted at LAAP, two risk assessments, a Baseline Risk Assessment (BRA)
and an expanded risk assessment, were conducted to evaluate the potential effects of the study
areas on human health and the environment. The expanded risk assessment was performed as part
of the Feasibility Study (FS) and was conducted using the same process as the BRA. However, it
presented additional exposure scenarios. The results of these risk assessments are presented in
detail in Section 6.0.

The final FS for LAAP was completed in September 1993, prior to the site being divided into
separate Soil/Source and Groundwater OUs. The BRA determined that the soil/sources at the seven
study areas did not pose an unacceptable risk to human health and the environment. Therefore,
the FS only considered the No Further Action alternative for the soil/source portion of the
site. The FS also presented remediation goals and remediation alternatives for groundwater.

In February 1995, the Department of the Army (DA), USEPA, and LDEQ agreed to divide LAAP into
two separate OUs, the Soil/Source OU and the Groundwater OU. The Final Proposed Remedial Action
Plan (Proposed Plan), completed December 15, 1995, and this ROD present the decision summary for
the Soil/Source OU.
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3.0 Highlights of Community Participation

The RI and BRA for the Soil/Source OU became final in February 1992. The FS became final in
September 1993. These documents are available to the public as part of the Administrative
Record and in the information repositories maintained at the LAAP installation. The
Administrative Record File is also available for review at USEPA and LDEQ offices,

The Proposed Plan was released to the public in January 1996. This document is also available
in the Administrative Record located in the information repositories listed above. The notice
of availability of these documents was published on January 9, 1996. A public comment period
was held from January 8, 1996 to February 6, 1996.

In addition, a public availability session and meeting was held on January 25, 1996. At this
meeting, representatives from the U.S. Army Environmental Center (USAEC), U.S. Environmental
Protection Agency (USEPA), and LDEQ addressed guestions and received comments about the remedial
alternatives under consideration. A response to the comments received during the public comment
period is included in the Responsiveness Summary, which is Appendix A of this ROD.

This ROD presents the selected remedial action for the Soil/Source OU. The selected remedy
presented in this ROD was chosen in accordance with CERCLA, as amended by SARA, and the NCP.
The decision for the Soil/Source OU is based on the Administrative Record.

4.0 Scope and Role of Response Action

This ROD addresses the final remedy for the Soil/Source OU consisting of soil/source areas at
seven study areas: Area P, BG-5, LF-3, OWL, BG-8 Landfill/Lagoon, and M-4 Lagoon.

The objectives of remedial actions for the Soil/Source OU include the protection of the
groundwater and prevention of direct contact with Area P soils. The IRA at Area P addressed
these objectives by removing chemical constituents from the soils, lagoon water, and wastewater.
The studies undertaken at LAAP have shown that no potential human health or environmental
risks are associated with the soils/sources at the other six study areas; therefore, there are
no remedial action objectives associated with the other study areas.

In keeping with the overall response strategy, the recommended remedial action for the
Soil/Source OU at LAAP is No Further Action. This consists of taking no further action
regarding the study area soil/source areas beyond the completed IRA.

5.0 Summary of Site Characteristics

5.1 Area P

The chemical source areas within Area P (see Figure 1-1) consist of the former pink water
lagoons. These 16 lagoons were active from the early 1940s until March 1981. Area P was also
used as a waste burning ground for a number of years. Numerous investigations have been
performed in Area P. These investigations were designed to determine if specific chemicals
remained in the soil and/or groundwater after the past burning and pink water operations that
were conducted in Area P.
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The soils investigations at Area P included the following:
• In 1978, eighty-six soil, sediment/sludge and surface soil samples were collected.
These samples were analyzed for Research and Development Explosive, cyclonite
hexahydro-1,3,5- trinitro-1,3,5-triazine (RDX) and High Melting Explosive,
cyclotetramethylenetetranitramine, octahydro-1,3,5,7-tetranitro-l,3,5,7-tetrazocine
(HMX) .
• In 1986, three additional samples were collected from one soil boring-one from the
ground surface; one between 10 and 20 feet; and one from the top few feet of the
Cane River Formation.

As approved by USEPA and LDEQ, an IRA was conducted from 1987 through 1990. This action took
place during the performance of the Supplemental RI field investigation conducted in 1990 and
1991. The purpose of the IRA was to protect the shallow groundwater at Area P by removing soil
containing more than 100 milligrams per kilogram (mg/kg) of HMX and RDX. The IRA activities
began with the collection of 24 soil and sediment samples from 19 locations. The next step of
the IRA consisted of excavation and treatment of lagoon sediment and soil by incineration, and
treatment of lagoon water and wastewater generated during the IRA activities prior to discharge.

Three hundred forty-five (345) soil samples were collected from the excavated areas at Area P to
confirm that the soil with HMX and RDX concentrations above 100 mg/kg had been removed. The soil
that remained was analyzed and found to contain concentrations of HMX and RDX ranging from
non-detectable levels to 91 mg/kg. Of the 345 samples collected, 267 had non-detectable levels
of explosive chemicals.

After the excavated soil was incinerated, the treated soil was returned to the excavated lagoons
to fill in the excavation. The filled lagoons were then covered with a cap. The cap was
constructed with clay 2 feet thick followed by 4 inches of topsoil planted with bermuda grass.
A four-strand barbed wire fence. 4 feet in height, was installed around the cap and the area
was posted with signs reading "Area P Decontamination Area."

5.2 BG-8 Landfill/Lagoon

The BG-8 Landfill (see Figure 1-1) is a 60-acre area that was used as a burning ground for
primarily non-explosive material from the 1950s until some time in the 1970s, and for disposal
of sanitary wastes (i.e., domestic sewage) and industrial wastes (waste residue from industrial
processes such as used oils, wastewater treatment sludges, etc.). Landfilling was conducted
from 1970 through December 1987 when operation ceased. The landfill was closed in 1988 per
closure reguirements issued to LAAP by the LDEQ Solid Waste Division. According to the closure
reguirements, the BG-8 Landfill was covered with "a compacted clay cap to a depth of 24 inches."
The closure reguirements also specified that the cap should be capable of supporting vegetation.
The site supports a well-established grass cover and no evidence of prior activities remain.

The BG-8 Lagoons did not have liners and were located east of the landfill. These lagoons were
used for the disposal of pink water waste in the late 1960s and 1970s. The lagoons were filled
with soil in 1977. The former BG-8 Lagoon area was most recently used to landfarm sludge from
the onsite wastewater treatment plant until 1984. Details of the BG-8 Lagoons are unknown, and
no records of the closure activities were kept. Chemicals such as RDX and HMX and volatile
organic compounds (VOCs) (xylene, toluene, methylbenzene) were detected in both surface and
subsurface soils at the BG-8 Landfill/Lagoon study areas.

Soil samples were collected from BG-8 Landfill/Lagoon during four investigations conducted
between 1982 and 1990. A total of 104 soil samples were collected from 33 locations at depths
of 0, 5, 10, and 15 feet. These samples were primarily collected from the former burning ground
and lagoon areas. Soil samples were located in areas most likely to contain the highest
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concentrations of RDX, HMX, and VOCs. These areas were primarily the former burning ground and
lagoon areas. Thus, those areas most likely to pose potential unacceptable risks and contribute
site-related constituents to the groundwater were characterized.

Concentrations of RDX and HMX in BG-8 Landfill/Lagoon surface soil samples ranged from
non-detect to 48.32 mg/kg with RDX (48.32 mg/kg) present at the highest concentrations. Lead
was also present in soil samples at concentrations ranging from 12.21 mg/kg to 48.32 mg/kg.
Concentrations of constituents dropped significantly with depth. The only explosive chemical
detected at the 5-foot interval was HMX at 1.3 mg/kg. No explosive chemicals or metals were
detected at either the 10-foot or 15-foot intervals.

5.3 BG-5

Open burning of explosives has been conducted at BG-5 (see Figure 1-1) since approximately
1947. By 1955, the burning ground consisted of at least six burning cages and several
detonation areas encompassing approximately 4.5 acres. In 1966, this study area consisted of
three raised earthen berms sloping toward a concrete basin on the western side of the site.
Rain falling on the burn pads flowed to the basin. The rainwater that had collected in the
concrete basin was treated in a wastewater treatment system on the installation, then
discharged. This basin was taken out of service, dismantled, and removed in 1983. Because BG-5
is still active, there is only sparse vegetation at the study area. A portion of the study area
slopes to a sand pit and some detonation depressions are visible.

Underground detonation of explosive wastes has been conducted since 1986. RDX; HMX;
N-methyl-N,2,4, 6-tetranitroaniline (tetryl); 2,4,6-trinitrotoluene; 1,3,5-trinitrobenzene;
2,4-dinitrotoluene; and 2,6-dinitrotoluene were detected in both the surface and subsurface
soils at BG-5. Soil samples were collected from BG-5 during three investigations conducted
between 1982 and 1989. A total of 57 soil samples were collected from 20 locations at a maximum
depth of 14 feet. These samples were collected from the area of the former burning ground.
Soil samples were located in areas most likely to contain the highest concentrations of RDX,
HMX, and other explosive chemicals. These area were primarily the former and existing burning
grounds. Thus, those areas most likely to pose potential unacceptable risks and contribute
site-related constituents to the groundwater were characterized. Concentrations of explosive
chemicals detected in BG-5 sod samples ranged from 0.6 to 100 mg/kg with RDX present at the
highest concentrations.

5.4 LF-3

LF-3 consists of nine former pink water lagoons covering an area of approximately 7.5 acres that
were used in the 1950s and 1960s (see Figure 1-1). The disposal of pink water at LF-3 was
stopped in the late 1960s. The lagoons were then used as landfills for non-explosive material
including building debris. The landfill operations were discontinued approximately in the
1970s. The LF-3 study area was then abandoned with no formal closure. Currently, large trees
are present in the area of the former lagoons. Soil samples were collected from Landfill 3
during three investigations conducted between 1982 and 1989. A total of 44 soil samples were
collected from 14 locations at a maximum depth of 40 feet at Study Area LF-3. Twelve of the
sample locations were within the perimeter of the LF-3 Study Area, and two of the locations were
outside of the study area to the north. Thus, those areas most likely to pose potential
unacceptable risks and contribute site-related constituents to the groundwater were
characterized. No explosive chemicals were detected in soil samples from LF-3.

5.5 OWL
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The production of 155-ntm ammunition metal parts at the Y-line production facility located
adjacent to the OWL began in 1952 (see Figure 1-1). From early 1960 to late 1975, a series of
three pits were used for the treatment of oily residues generated from the production process.
These pits encompassed an area of approximately 4 acres. These residues were allowed to settle
in the oil pits after settling agents had been added. The waters resulting from the settling
process were allowed to flow over-land and enter Boone Creek. The settled residues (sludge)
were collected and worked into the soil in the surrounding area. In 1975, the pits were filled
in with clean dirt. The OWL is barely discernable from the surrounding area as there is no
surface expression of the former pits and the area is becoming overgrown with shrubs and brush.

As a result of the use of the three pits and sludge disposal (landfarming) activities, the
surface and subsurface soils were suspected to contain metals. Soil samples were collected at
the OWL during two investigations conducted in 1989 and 1990. A total of 76 soil samples were
collected from 21 locations at a maximum depth of 15 feet. Fourteen of these sample locations
were situated within the former landfarm area of OWL, and 10 of these locations were situated
directly east of the landfarm area. These were the areas most likely to contain the highest
concentrations of VOCs and metals. These areas were primarily the former and existing burning
grounds. Thus, those areas most likely to pose potential unacceptable risks and contribute
site-related constituents to the groundwater were characterized. Concentrations of arsenic and
lead in OWL soil samples ranged from 1.2 mg/kg to 18 mg/kg with lead being present at the
highest concentrations. No VOCs were detected in OWL soil samples.

5.6 M4 Lagoon

The 0.2-acre M-4 Lagoon area (see Figure 1-1) was used from the 1960s until the early 1990s for
the manufacture of ammunition metal parts, including the machining and metal plating of grenade
components. The unlined lagoon was used from 1962 to 1964 to receive treated wastewater from
the electroplating operation. This wastewater contained cyanide, cadmium, chromium, and zinc.
As a result of past industrial activities, subsurface soils around the lagoon contain cyanide in
concentrations ranging from non-detect to 1.91 mg/kg. However, cyanide was only detected in
two of the eight borings sampled. The lagoon is still present and continually contains water.

Two surface water and five sediment samples were collected from the interior of the Lagoon
In 1986. These samples were analyzed for the presence of metals. Metals were not detected in
the surface water or the sediment in the M-4 Lagoon. Additional soil samples were subseguently
collected at the M-4 Lagoon study area during an investigation conducted in 1989. During the
1989 investigation, a total of 24 soil samples were collected from eight soil borings at a
maximum depth of 15 feet. These sample locations were situated primarily north and east of the
M-4 Lagoon. Samples were collected from areas most likely to contain the highest concentrations
of cyanide and metals in order to characterize those areas most likely to pose potential
unacceptable risks and contribute site-related constituents to the groundwater. Samples
collected from the sludge present in the M-4 Lagoon were analyzed for the following inorganic
constituents: cyanide, arsenic, barium, cadmium, chromium, lead, and mercury. The only
constituent detected in significant concentrations was cyanide (1.82 to 4.85 mg/kg detected).
No metals or cyanide were detected in M-4 Lagoon soil samples.

6.0 Summary of Site Risks

In order to characterize the potential current and future threats to human health and the
environment that may be posed by the COCs at the Soil/Source OU, two risk assessments were
conducted in accordance with USEPA's Risk Assessment Guidance for Superfund (RAGS) : Volumes I -
Human Health Evaluation Manual (Part A) and Volume II - Environmental Evaluation Manual. These
two risk assessments were the BRA and the expanded risk assessment. The expanded risk assessment
was performed as part of the FS to address exposure scenarios not originally addressed in the
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BRA conducted as part of the RI. The expanded risk assessment was conducted using the same
process as the BRA.

Both the BRA and the expanded risk assessment evaluated each of the seven study areas to
determine if they pose the potential for current or future health risks to humans or adverse
effects on the environment. The BRA considered current worker exposure and future unrestricted
land use (i.e., residential use) of the seven study areas in accordance with USEPA's RAGS. The
expanded risk assessment, performed as part of the FS, was also conducted in accordance with
RAGS. The expanded risk assessment considered future worker and future recreational exposure
scenarios.

6.1 Identification of Constituents of Concern

Constituents of concern (COCs) were identified in order to streamline the risk assessment
process by identifying chemicals that contribute most significantly to overall potential risk.
COCs were evaluated separately for air, soil, groundwater, surface water, and sediment.
Explosives, VOCs, and metals were identified as COCs based on methods presented in the RAGS and
discussed in detail in the BRA for LAAP (ESE, 1992). These chemicals represent the most mobile,
toxic, and freguently detected chemicals at LAAP. The COCs identified in the soil/source areas
in the LAAP study areas are presented in Table 6-1.

6.2 Exposure Assessment

The BRA interpreted the RI data in order to (1) identify those exposure pathways that may pose
a current or future potential risk to human health and the environment, and (2) determine the
degree of this potential risk. An exposure pathway is the route that a chemical or physical
agent takes from a source to an exposed population or individual (receptor). The BRA evaluated
each human exposure pathway for completeness and determined that there were two significant
exposure scenarios. The significant human exposure scenarios for the soil/source areas
addressed in the BRA included:
• Current worker exposure to soil; and
• Future residential exposure to soil.
-------
Table 6-1. Chemicals of Concern in Soil by Study Area

Site Chemicals of Concern
Area P 1,3-Dinitrobenzene RDX
2,4-Dinitrotoluene Tetryl
2,6-Dinitrotoluene 1,3,5-Trinitrobenzene
HMX 2,4,6-Trinitrotoluene
Nitrobenzene

BG-5 1,3-Dinitrobenzene* RDX*
2,4-Dinitrotoluene Tetryl
2,6-Dinitrotoluene 1,3,5-Trinitrobenzene*
HMX 2,4,6-Trinitrotoluene*

BG-8 1,1-Dichloroethene Nitrobenzene
1,3-Dinitrobenzene* RDX
2,4-Dinitrotoluene Tetryl
2,6-Dinitrotoluene 1,3,5-Trinitrobenzene*
HMX 2,4,6-Trinitrotoluene*
Lead

LF-3 1,3-Dinitrobenzene RDX
2,4-Dinitrotoluene Tetryl
2,6-Dinitrotoluene 1,3,5-Trinitrobenzene*
HMX

M-4 Lagoon No COCs in soil

OWL No COCs in soil

* Indicates those constituents which contributed most significantly to the overall site risk
associated with surface soils.

HMX = High Melting Explosive, cyclotetramethylenetetranitramine, octahydro-1,3,5,7-
tetranitro-1,3,5,7-tetrazocine.
RDX = Research and Demolition Explosive, cyclonite hexahydro-1,3,5-trinitro-l,3,5-triazine.
tetryl = N-methyl-N,2,4,6-tetranitroaniline.

Source: ESE, 1996.
-------
The primary human exposure pathways evaluated for two human exposure scenarios (current worker
and future residential) considered in the BRA are as follows:

• Direct skin contact and unintentional eating of COCs in surface soil, and
• Inhaling of COCs in dust generated from surface soil.

Other exposure pathways, such as eating fish, game and plants, were evaluated and determined to
be potentially complete at LAAP. However, as these pathways do not contribute significantly to
the overall amount of chemicals that would be taken in at the individual study areas, eating of
fish, game and plants were screened out during the exposure assessment and were not evaluated
further in the BRA. The exposure formulas and exposure factors used to calculate chemical
intakes in the BRA are presented in Table 6-2.

Currently, no activities occur at the BG-8 Landfill/Lagoon or OWL; therefore, current worker
exposure to soil was guantitatively evaluated for Area P, BG-5, and LF-3 only. Future
residential exposure to soil was guantitatively evaluated for Area P, BG-5, BG-8
Landfill/Lagoon, LF-3, and OWL. Exposure to soil at the M-4 Lagoon was not evaluated since
surface soil is not a concern at this study area.

Since residential and agricultural use of LAAP is not likely, a separate, expanded risk
assessment was performed as part of the FS Report. This expanded risk assessment was conducted
using more likely exposure scenarios than the BRA. Since the installation will continue to be
used for munitions production, access to LAAP will remain restricted for safety and national
security reasons. Only workers and other authorized personnel can enter the installation
through security checkpoints, because the installation is completely fenced. Therefore, current
onsite worker exposure, future worker exposure, and future recreational exposure just outside
the installation boundaries are the most likely human exposure scenarios that would occur at the
installation. The exposure formulas and exposure factors used to calculate chemical intakes in
the expanded risk assessment are presented in Table 6-3.

6.3 Toxicity Assessment

The purpose of the toxicity assessment is to identify acceptable levels of COCs in the
environment. Available toxicity factors of carcinogenic and non-carcinogenic COCs are discussed
and presented in the BRA Report. The COCs selected for the risk assessment for the site have a
wide range of carcinogenic and non-carcinogenic effects associated with them. The reference
dose (RfD) values and carcinogenic slope factors (CSF) were key dose-response variables used in
the BRA. The RfD, expressed in units of milligrams per kilogram per day (mg/kg/day) for a
specific chemical is an estimated daily intake rate that appears to pose no risk over a lifetime
of exposure. The RfD value is used to assess non-carcinogenic effects. The RfDs for the COCs at
the Soil/Source OU are shown in Table 6-4. The CSF, expressed in units of (mg/kg/day) -1
provides a conservative estimate of the probability of cancer development from a lifetime of
exposure to a particular level of a potential carcinogen. The CSFs for potential carcinogens
present at the Soil/Source OU are presented in Table 6-5.
-------
Table 6-2. Formulas and Factors Used in the Exposure Pathways Evaluated in the BRA (Page 1 of 5)

INGESTION OF SOIL

For adult and child exposure:

I = CS * IR * CF * FI * BF * EF * ED
BW * AT

Where: I = intake; the amount of chemical at the exchange boundary (mg/kg-body weight/day)
CS = chemical concentration in soil [lesser of the maximum detected concentration and the 95
percent upper confident limit (UCL 95) of the mean concentration; mg/kg]
IR = soil ingestion rate (mg/day)
CF = conversion factor for soil (10 -6 kg/mg)
FI = fraction of soil ingested from contaminated source (unitless)
= 1.0 (assumes 100% of ingested soil is from contaminated area)
BF = bioavailability factor; the amount of a chemical that is available for absorption through the
gastrointestinal lining (unitless)
=0.1 for lead (EPA, Health Effects Assessment for Lead, 1984)
= 1.0 default value for all chemicals except lead
EF = exposure freguency (days/year)
ED = exposure duration (years)
BW = body weight (kg)
AT = averaging time (period over which the exposure is averaged; days)

Current Worker:
IR = 30 mg/day [standard default for industrial exposure (EPA, 1991)]
EF = 200 days/year for BG-5 and M-4 [percentage of dry days per year (305/365) multiplied by
the number of days per year working in the area (240) (Burroughs, 1991)}
= 5 days/year for LF-3 [the grass around the flow eguilibration tank is cut approximately
one time per month from April through August (Burroughs, 1991)]
ED = 25 years [default value for industrial exposure (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1998)
= 70 years * 365 days year for carcinogenic effects (EPA, 1989)
-------
Future Residential (Adult):
IR = 100 ing/day [default value for adult residential exposure (EPA, 1991)]
EF = 350 days/year [default value for residential exposure (EPA, 1991)]
ED = 30 years [default for residential exposure (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)

Future Residential (Child):
IR = 200 ing/day (default value for child residential exposure (EPA, 1991)]
EF = 350 days/year (default value for residential exposure (EPA, 1991)]
ED = 6 years [assumes exposure for children age = 1 to 6 years, inclusive, in rural/residential
areas (EPA, 1991)]
BW = 15 kg [average (male and female) of 50th percentile values for age = 1 to 6 years (EPA.
1985)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
-------
Table 6-2. Formulas and Factors Used In the Exposure Pathways Evaluated in ERA (Page 2 of 5)

INGESTION OF SOIL (cont.)

For lifetime exposure:

i IR ED BW
1 200 6 15
2 100 24 70

Y c = CS * CF * FI * BF * EF / AT

Where: I = intake; the amount of chemical at the exchange boundary (mg/kg-body weight/day)
CS = chemical concentration in soil [lesser of the maximum detected concentration and the 95
percent upper confident limit (UCL 95) of the mean concentration; mg/kg]
IR = soil ingestion rate (mg/day)
CF = conversion factor for soil (10 -4 kg/mg)
FI = fraction of soil ingested from contaminated source (unitless)
= 1.0 (assumes 100% of ingested soil is from contaminated area)
BF = bioavailability factor, the amount of a chemical that is available for absorption through the
gastrointestinal lining (unitless)
=0.1 for lead (EPA, Health Effects Assessment for Lead, 1984)
= 1.0 default value for all chemicals except lead
EF = exposure freguency (days/year)
ED = exposure duration (years)
BW = body weight (kg)
AT = averaging time (period over which the exposure is averaged; days)

Future Residential (Lifetime):
EF = 350 days/year [default value for residential exposure (EPA, 1991)]
AT = 70 years * 365 days/year for carcinogenic effects (EPA, 1989)

DIRECT CONTACT WITH SOIL

I = CS * CF * SA * AF * ABS * EF * ED
BW * AT
-------
Table 6-2. Formulas and Factors Used in the Exposure Pathways Evaluated in the BRA (Page 3 of 5)

Where: I = intake, the amount of chemical at the exchange boundary (mg/kg-body weight/day)
CS = chemical concentration in soil [lesser of the maximum detected concentration and the 95
percent upper confident limit (UCL 95) of the mean concentration; mg/kg]
CF = conversion factor for soil (10 -6 kg/mg)
SA = skin surface area available for contact (cm 2/event) [All surface area values am 50
percentile values from EPA, 1985. 50 percentile values are used because surface area is
related to body weight, and average body weights over the ED were used in the exposure
calculations.]
AF = soil-to-skin adherence factor (mg/cm 2)
=2.11 mg/cm 2 [value for kaolin clay on hands (EPA, Superfund Exposure Assessment
Manual, 1988); used because site soils consist predominantly of clay with some sand
(ESE, 1990), and clay has a higher AF than sand or potting soil]

DIRECT CONTACT WITH SOIL (cont.)

ABS = chemical-specific skin absorption factor (unitless)
= 0.25 for volatile organic chemicals (Ryan et al., 1987)
= 0.10 for semivolatile organic chemicals, other than PCBs (Ryan et al., 1987)
=0.05 for PCBs (Ryan et al., 1987)
= 0.01 for inorganics, other than chromium VI (Ryan et al., 1987)
=0.15 for chromium VI (Hawley, 1985)
EF = exposure freguency (days/year)
ED = exposure duration (years)
BW = body weight(kg)
AT = averaging time (period over which the exposure is averaged; days)
-------
Current Worker:
SA = 1,506 cm 2 [Based on average adult (male and female) surface areas (m2) for hands and
Ehead multiplied by a conversion factor of 10,000 cm 2/m 2. According to Standard
Operating Procedures, base personnel are reguired to wear long pants, a long-sleeved
shirt, and gloves while working (Thiokol, 1990). For conservativeness, it is assumed that
workers will remove their gloves occasionally during breaks.)
EF = 200 days/year for BG-5 and M-4 [percentage of dry days per year (305/365) multiplied
by the number of days per year working in the area (240) (Burroughs, 1991)]
= 5 days/year for LF-3 [the grass around the flow eguilibration tank is cut approximately
one time per month from April through August (Burroughs, 1991)]
ED = 25 years [default value for industrial exposure (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
-------
Table 6-2. Formulas and Factors Used in the Exposure Pathways Evaluated in the BRA (Page 4 of 5)

AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 years * 365 days/year for carcinogenic effects (EPA, 1989)

Future Residential (Adult and Lifetime):
SA = 5,314 cm2 [Based on average adult (male and female) body part surface areas (m2)
multiplied by a conversion factor of 10,000 cm 2/m 2. Assumes 112 days/year partially
clothed (exposure of bands, arms, feet, legs, and Ehead assumed to apply 5 days/week
when average maximum monthly air temperature exceeds 805F {5/7 x 157 = 112
days/year}) and remainder of time spent fully clothed (exposure limited to hands,
forearms, and Ehead).]

Future Residential (Adult and Lifetime), Cont.:
EF = 350 days/year [default value for residential exposure (EPA, 1991)]
ED = 30 years [default for residential exposure (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 years * 365 days/year for carcinogenic effects (EPA, 1989)

DIRECT CONTACT WITH SOIL (cont.)

Future Residential (Child):
SA = 2,494 cm 2 [Based on average (male and female) mean percentage of total body surface
area by part (m 2) over the age range multiplied by the average (male and female) such
percentile total body surface are over that age range. The final values were multiplied by
a conversion factor Of 10,000 CM 2/M 2. Assumes 112 days/year partially clothed (exposure
of hands, arms, feet, legs, and Ehead assumed to apply 5 days/week when average
maximum monthly air temperature exceeds 805F {5/7 x 157 = 112 days/year}) and
remainder of time spent fully clothed (exposure limited to hands, forearms, and Ehead).]
EF = 350 days/year [default value for residential exposure (EPA, 1991)]
ED =6 years [assumes exposure for children age = 1 to 6 years, inclusive, in rural/residential
areas (EPA, 1991)]
BW = 15 kg [average (male and female) of 50th percentile values for age = 1 to 6 years (EPA,
1985)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
-------
Table 6-2. Formulas and Factors Used in the Exposure Pathways Evaluated in the BRA (Page 5 of 5)

INHALATION OF SOIL PARTICULATES

1= CS * RFC * IR * CF * EF * ED
BW * AT

Where: I = intake; the amount of chemical at the exchange boundary (mg/kg-body weight L/day)
CS = chemical concentration in soil [Lesser of the maximum detected concentration and the 95
percent upper confident limit (UCL 95) of the mean concentration; mg/kg]
RFC = respirable particulate (PM 10) concentration in air (mg/m 3)
= 59.5 Ig/m 3 [Maximum 24-hour average total suspended particulate concentration detected
at 2 air sampling stations at LAAP for the period 10/1/86 to 4/30/87 (Thiokol, 1987).
Generally, only particles with a diameter less than 10 Im may be available for absorption
through the alveolar membranes. Although the value provided by Thiokol (1987) is for
total suspended particulates, which includes particulates of all sizes, this number will be
used to provide a very conservative value for absorbable inhaled particulates.]
IR = ambient air inhalation rate (m 3/day)
CF = conversion factor for soil (10 -4 kg/mg)
EF = exposure freguency (days/year)
ED = exposure duration (years)
BW = body weight (kg)
AT = averaging time (period over which the exposure is averaged; days)
-------
INHALATION OF SOIL PARTICULATES (cont.)

Current Worker:
IR = 20 m 3/day [standard default for industrial exposure (EPA, 1991)]
EF = 120 days/year for Area P [percentage of dry days per year (305/365) multiplied by the
percent days per year working in the area (240 x 3/5) (Burroughs, 1991). Access to Area
P is restricted, and no exposure to soils inside this fenced area is expected; however,
persons working at the nearby maintenance shed may be exposed to airborne particulates
migrating from the contaminated area.]
= 200 days/year for BG-5 and M-4 [percentage of dry days per year (305/365) multiplied
by the number of days per year working in the area (240) (Burroughs, 1991)]
= 5 days/year for LF-3 [the grass; around the flow eguilibration tank is cut approximately
one time per month from April through August (Burroughs, 1991)]
ED = 25 years [default value for industrial exposure (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 years * 365 days/year for carcinogenic effects (EPA, 1989)

Future Residential (Adult and Lifetime):
IR = 15 m 3/day (default value for adult residential exposure (EPA, 1991)]
EF = 350 days/year [default value for residential exposure (EPA, 1991)]
ED = 30 years [default for residential exposure (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 years * 365 days/year for carcinogenic effects (EPA, 1989)

Future Residential (Child):
IR = 19 m 3/day (reasonably conservative inhalation rate for a child based on the adult IR value
and the child:adult ratio for ambient air intake (25.4 m 3/day {based on the child MLE
value and the adult RME:MLE ratio in EPA, 1985} « 20 m 3/day {conservative inhalation
rate for total indoor and outdoor residential exposure in EPA, 1991}).]
EF = 350 days/year [default value for residential exposure (EPA, 1991)]
ED =6 years [assumes exposure for children age = 1 to 6 years, inclusive, in rural/residential
areas (EPA, 1991)]
BW = 15 kg [average (male and female) of 5th percentile values for age = 1 to 6 years (EPA,
1985)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
Source: ESE, 1996.
-------
Table 6-3. Formulas and Factors Used in the Exposure Pathways Evaluated in the Expanded RA (Page 1 of 3)

INGESTION OF SOIL

I = CS * IR * CF * FI * EF * ED
BW * AT
Where:
I = intake; the amount of chemical at the exchange boundary (mg/kg-body weight/day)
CS = chemical concentration in soil [lesser of the maximum detected concentration and the 95
percent upper confident limit (UCL 95) of the mean concentration; mg/kg]
IR = soil ingestion rate (mg/day)
CF = conversion factor for soil (10 -6 kg/mg)
FI = fraction of soil ingested from contaminated source (unitless)
= 1.0 (assumes 100% of ingested soil is from contaminated area)
EF = exposure freguency (days/year)
ED = exposure duration (years)
BW = body weight (kg)
AT = averaging time (period over which the exposure is averaged; days)

Current and Future Worker (RME):
IR = 50 mg/day [standard default for industrial exposure (EPA, 1991)]
EF = 250 days/year [standard default for industrial exposure (EPA, 1991)]
ED = 25 years [national 95 th percentile time at one workplace (EPA. 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 years * 365 days/year for carcinogenic effects (EPA, 1989)

Current and Future Worker (CT):
IR = 50 mg/day [standard default for industrial exposure (EPA, 1991)]
EF = 250 days/year [standard default for industrial exposure (EPA, 1991)]
ED =9 year [national 50 th percentile time at one workplace (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 years * 365 days/year for carcinogenic effects (EPA, 1989)
-------
DIRECT CONTACT WITH SOIL
I =
CS * CF * SA * AF * ABS * EF * ED
BW * AT
Where:

I = intake; the amount of chemical at the exchange boundary (mg/kg-body weight/day)
CS = chemical concentration in soil [lesser of the maximum detected concentration and the 95
percent upper confident limit (UCL 95) of the mean concentration; mg/kg]
CF = conversion factor for soil (10 -6 kg/mg)
SA = skin surface area available for contact (cm 2/event) [All surface area values are 50 th
percentile values from EPA, 1985. 50 th percentile values are used because surface am is
related to body weight, and average body weights over the ED were used in the exposure
calculations.]
AF = soil-to-skin adherence factor (mg/cm#)

Table 6-3. Formulas and Factors Used in the Exposures Pathways Evaluated in the Expanded RA (Page 2 of 3)

DIRECT CONTACT WITH SOIL (cont.)
ABS = chemical-specific skin absorption factor (unitless)
= 0.23 for volatile organic chemicals (Ryan et al., 1987)
= 0.10 for semivolatile organic chemicals, other than PCBs (Ryan et al. , 1987)
=0.05 tor PCBs (Ryan et al., 1987)
= 0.01 for inorganics, other than chromium VI (Ryan et al., 1987)
=0.15 for chromium VI (Hawley, 1985)
EF = exposure freguency (days/year)
ED = exposure duration (years)
BW = body weight (kg)
AT = averaging time (period over which the exposure is averaged; days)
-------
Current and Future Worker (RME):
SA = 1,506 cm# [Based on average adult (male and female) surface areas (m 2) for hands and
Ehead multiplied by a conversion factor of 10,000 cm#/m#. According to Standard
Operating Procedures, base personnel am reguired to wear long pants, a long-sleeved
shirt, and gloves while working (Thiokol, 1990). For conservativeness, it is assumed
that workers will remove their gloves occasionally during breaks.]
EF = 250 days/year [standard default for industrial exposure (EPA, 1991)]
ED = 25 years [national 95 th percentile time at one workplace (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
AT = E3) * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 years * 365 days/year for carcinogenic effects (EPA, 1989)

Current and Future Worker (CT):
SA = 1,506 cm# (Based on average adult (male and female) surface areas (m#) for hands and
E head multiplied by a conversion factor of 10,000 cm#/m#. According to Standard
Operating Procedures, base personnel am reguired to wear long pants, a long-sleeved
shirt, and gloves while working (Thiokol, 1990). For conservativeness, it is assumed
that workers will remove their gloves occasionally during breaks.)
EF = 250 days/year [standard default for industrial exposure (EPA, 1991)]
ED =9 years [national 50th percentile time at one workplace (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA. 1991))
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 year * 365 days/year for carcinogenic effects (EPA, 1989)

INHALATION OF SOIL PARTICULATES

CS * RPC * IR * CF * EF * ED
I = BW * AT
Where:
I = intake, the amount of chemical at the exchange boundary (mg/kg-body weight/day)
CS = chemical concentration in soil [lesser of the maximum detected concentration and the 95
percent upper confident limit (UCL 95) of the mean concentration; mg/kg]
-------
Table 6-3. Formulas and Factors Used in the Exposure Pathways Evaluated in the Expanded RA (Page 3 of 3)

INHALATION OF SOIL PARTICULATES (cont.)

RFC = respirable particulate (PM 10) concentration in air (mg/m 3)
= 59.5 Ig/m 3 [Maximum 24-hour average total suspended particulate concentration detected
at 2 air sampling stations at LAAP for the period 10/1/86 to 4/30/87 (Thiokol, 1987) .
Generally, only particles with a diameter less than 10 Im may be available for absorption
through the alveolar membranes. Although the value provided by Thiokol (1987) is for
total suspended particulates, which includes particulates of all sizes, this number will be
used to provide a very conservative value for absorbable inhaled particulates.]
IR = ambient air inhalation rate (m 3/day)
CF = conversion factor for soil (10 -4kg/mg)
EF = exposure freguency (days/year)
ED = exposure duration (days/year)
BW = body weight (kg)
AT = averaging time (period over which the exposure is averaged; days)

Current and Future Worker (RME):
IR = 20 m 3/day [standard default for industrial exposure (EPA, 1991)]
EF = 250 days/year [standard default for industrial exposure (EPA, 1991)]
ED = 25 years [national 95 th percentile time at one workplace (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA. 1991)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 years * 365 days/year for carcinogenic effects (EPA, 1989)

Current and Future Worker (CT):
IR = 20 m 3/day (standard default for industrial exposure (EPA, 1991)]
EF = 250 days/year [standard default for industrial exposure (EPA, 1991)]
ED =9 years [national 50 th percentile time at one workplace (EPA, 1991)]
BW = 70 kg [default value for adult body weight (EPA, 1991)]
AT = ED * 365 days/year for non-carcinogenic effects (EPA, 1989)
= 70 years * 365 days/year or carcinogenic effects (EPA. 1989)
NOTE:
RME =reasonable maximum exposure.
CT =central tendency.

Source: ESE, 1996.
-------
6.4 Risk Characterization

Existing data were used for the BRA to determine whether COCs detected at LAAP may pose a
potential risk to human health and the environment. If data were not available, then suitable
environmental models were used to predict exposures. Potential risks to human health were then
evaluated with respect to carcinogenic and non-carcinogenic effects.

The potential risks associated with exposure to individual carcinogens are calculated by
multiplying the chemical intake by the CSF as follows:

Risk = I * CSF

where: Risk = probability for an individual developing cancer under the assumed
exposure conditions (unitless);
I = daily chemical intake averaged over a lifetime of 70 years
(mg/kg/day) ; and
CSF = carcinogenic slope factor, expressed in (mg/kg/day) -1.

The combined risk from exposure to multiple chemicals is evaluated by addition of resultant
risks from different chemicals as follows:

where: Risk T = the sum of individual chemical risks, unitless probability; and
Risk i = the risk estimate for the i th chemical.

Risks are also added across exposure pathways if the exposures are to the same individual (e.g,
a worker could be exposed to soil by oral, dermal, and, if relevant, inhalation).

Risk soil = Risk oral + Risk dermal + Risk inhalation

USEPA's acceptable increased cancer risk range is 1.0x10 -6 to 1.0x10 -4 (one individual in
1,000,000 to one individual in 10,000) as established in the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP). The number l.Oxl -4 corresponds to a probability
of one additional individual in 10,000 developing cancer from a lifetime (70 years) of
exposure to chemicals on the installation. This additional cancer risk is a risk in excess of
the natural incidence of cancer in the United States of two to three individuals in ten.#

Non-carcinogenic health risks are estimated by comparing actual or expected exposure levels to
acceptable concentrations to produce a hazard guotient (HQ) as follows:

HQ = I
RaD (5-3)

where: I = intake of chemical (mg/kg/day); and
RfD = reference dose of chemical (mg/kg/day).

The combined hazard from exposure to multiple chemicals is evaluated by addition of resultant
HQs to produce a hazard index (HI) as follows:

HI =11+ I 2 + ... + I i (5-4)
RaD 1 RaD 2 RaD i
-------
where: I i = Intake for the i th chemical (mg/kg/day); and
RaD i = reference dose for the i th chemical (mg/kg/day).

Similar to cancer risks, HQs may also be added across exposure pathways if the exposures are to
the same individual.

HI soil = HQ oral + HQ dermal + HI inhalation
An HQ or HI exceeding 1.0 indicates a potential unacceptable risk and a possible concern for
potential toxic effects.

Potential, risks to ecological receptors are evaluated by comparing actual or expected chemical
intakes (for terrestrial animals) or exposure point concentrations (for direct exposure of
plants or aguatic life) to acceptable intakes/concentrations to produce an ecotoxicity guotient
(EQ) as follows:

EQ = I or EC
TBC I TBC C

where: EC = exposure point concentration (mg/kg or mg/L),
I = intake of chemical (mg/kg/day);
TBC C = chemical concentration to be considered as "safe" (mg/kg or mg/L); and
TBC I = intake to be considered as a "safe dose" (mg/kg/day).

2 Letter dated May 22, 1995 from Ms. Cathy Gilmore, USEPA Region VI, to Mr. Doyle
Williams, LAAP.

As in the case of His, EQs in excess of 1.0 represent potential unacceptable risks to the
environment (e.g., land plants, water plants, and animals).

Potential increased carcinogenic risks associated with current worker sod exposure did not
exceed USEPA's acceptable risk range of 1.0x10 -6 to 10 -4 at any of the study areas evaluated.
Also, His associated with soil exposure did not exceed the target HI of 1. Therefore, current
worker exposure to soils at Area P, BG-5, and LF-3 are not expected to result in any
unacceptable cancer risk or hazard.

Potential increased carcinogenic risks associated with future residential sod exposure did not
exceed USEPA's acceptable risk range at any of the study areas. However, residential exposure
to soil at BG-5, BG-8 Landfill/Lagoon, and LF-3 may result in His exceeding the target HI of 1
(His ranged from 1 to 3). While future residential exposure to soils at these study areas may
not result in severe hazards, it may reduce the margin of safety incorporated in the exposure
evaluations.

The potential risks associated with the COCs at each study area, as calculated in the BRA, are
summarized in Table 6-6.
-------
Table 6-4. Chronic Toxicity Values for Potential Non-carcinogenic Effects of the Soil COCs
Exposure Pathway/ Chronic RfD
Chemical of Concern (mg/kg/day)
Oral Exposure

1,1-Dichloroethene

1,3-Dinitrobenzene

2,4-Dinitrotoluene

2,6 Dinitrotoluene
HMX

Lead
Nitrobenzene
9 X 10 -3

1 x 10 -4

2 x 10 -3

1 x 10 -3

5 x 10 -2

ND *
5 x 10 -4
RDX 3x3-3

Tetryl 1 x 10 -2

1,3,5-Trinitrobenzene 5 x 10 -3

2,4,6-Trinitrotoluene 5 x 10 -4
Confidence
Level
Medium
Low
High
Low

Low

High

Low

Medium
Critical
Effect
Liver effects

Increased spleen
weight
Nervous system
and blood effects
Nervous system.
blood, and kidney
effects
Liver effects
Adrenal gland,
blood, kidney,
and liver effects
Prostate gland
inflammation
Liver, kidney,
and spleen effects
Increased spleen
weight
Liver effects
RfD Basis/
RfD Source
Drinking Water Study/
IRIS, 1994
Drinking Water Study/
IRIS,1994
Diet (Food) Study/
IRIS, 1994
Diet (Food Study/
HEAST, 1994

Diet (Food) Study/
IRIS, 1994

Inhalation Study/
IRIS, 1994

Diet (Food) Study/
IRIS, 1994
Oral (Gavage) Study/
HEAST, 1994
Drinking Water Study/
IRIS, 1994
Diet (Food) Study/
IRIS. 1994
Uncertainty and
Modifying Factors
UF = 1,000 (A,H,L)
MF = 1
UF = 3,000 (A,H,R,S)
MF = 1
UF = 100 (A, H)
MF = 1
UF = 3,000 (A,H,R,S)
MF = 1

UF = 1,000 (A,H.S)
MF = 1

UF = 10,000 (A,H,L,S)
MF = 1

UF = 100 (A.H)
MF = 1
UF = 10,000 (A,H,L,S)
MF = 1
UF = 10,000 (A,H,S,X)
MF = 1

UF = 1,000 (A,H,L)
MF = 1
-------
Inhalation Exposure
All Chemicals
ND
Notes: -- = not applicable.
ND = not determined.
RfD = reference dose; dose of a chemical that is
not expected to result in an adverse effect
with a lifetime exposure.
UF = uncertainty factor.
MF = modifying factor.
IRIS = EPA's Integrated Risk Information System.
LOAEL = the lowest dose level at which an adverse
effect was observed.
NOAEL = the highest dose level at which no adverse
effects was observed.
mg/kg/day = milligrams per kilogram per day.
Uncertainty adjustments:
A = extrapolation from an animal study to
human effects.
H = variation in human sensitivity.
L = extrapolation from a LOAEL to a NOAEL.
R = lack of sub-chronic and reproductive toxicity
data.
S = extrapolation from a sub-chronic to a
chronic NOAEL.
X = derivation of an RfD based on a study on a
structurally similar chemical (1,3-
dinitrobenzene).
* By comparison to most other environmental toxicants, the degree of uncertainty about the health effects of lead is guite
low. It appears that some of these effects, particularly changes in the levels of certain blood enzymes and in aspects of
children's neurobehavioral development, may occur at blood lead levels so low as to be essentially without a threshold. EPA's
RfD Work Group considers it inappropriate to develop RfD for inorganic lead. EPA prefers to use the Integrated Exposure
Uptake Biokinetic (IEUBK) Model (EPA, 1991) to evaluated total lead exposure on a site-specific basis.
Source: ESE, 1996.
-------
Table 6-5. Toxicity Values for Potential Carcinogenic Effects of the Soil COCs
Weight-of-
CSF
(mg/kg/day) -1
Exposure Pathway/ Chemical of
Concern
Oral Exposure
1,1-Dichloroethene
2,4-Dinitrotoluene/
2,6-Dinitrotoluene
Lead

RDX

2,4,6-Trinitrotoluene

Inhalation Exposure
1,1-Dichloroethene
2,4-Dinitrotoluene/
2,6-DNT
Lead
RDX
2,4,6-Trinitrotoluene
Evidence
Classification
Type of
Cancer*
6.0 x 10 -3

6.8 x 10 -1 (a)

NSF (b)

1.1 x 10 -1

3.0 x 10 -#

1.8 X 10 -1

NSF
NSF (b)
NSF
NSF
C

B2
B2
C
C
CSF Basis/CSF Source
Drinking Water Study /
IRIS, 1994
Drinking Water Study /
IRIS, 1994
Drinking Water Study /
IRIS, 1994
Drinking Water Study /
IRIS, 1994
Drinking Water Study /
IRIS, 1994
Inhalation Study
IRIS, 1994

NSF/NSF
NSF/NSF
NSF/NSF
NSF/NSF
IRIS = EPA's Integrated Risk Information System.
NSF = No CSF is available.
= Not categorized by EPA as a Group A human carcinogen.
mg/kg/day = Milligrams per kilogram per day.

CSF: The probability of a response per unit intake of a chemical over a lifetime. CSF is used to estimate an upperbound
probability of an individual developing cancer as a result of an exposure to a particular level of a chemical.
Weight-of-evidence classification: An EPA classification system for characterizing the extent to which the available data
indicate that a chemical is a human carcinogen.
-------
A = Known human carcinogen; sufficient evidence from epidemiologic studies to support a causal association between chemical
exposure and cancer in humans.
B2 = Probable human carcinogen; sufficient evidence of carcinogenicity in animal studies but inadeguate or no evidence in
humans.
C = Possible human carcinogen; limited evidence of carcinogenicity in animal studies and no evidence in humans.
(a) CSF is based on a mixture of 2,4- and 2,6-dinitrotoluene.
(b) By comparison to most other environmental toxicants the degree of uncertainty about the health effects of lead is guite
low. It appears that some of these effects, particularly changes in the levels of certain blood enzymes; and in aspects of
children's neurobehavioral development, may occur at blood lead levels so low as to be essentially without a threshold. EPA
prefers to use the Integrated Exposure Uptake Biokinetic (IEUBK) Model (EPA, 1991) to evaluate total lead exposure on a
site-specific basis.

* In accordance with Risk Assessment Guidance for Superfund, types of cancer are only presented for
EPA Group A (known human) carcinogens. None of the soil COCs at LAAP am Group A
carcinogens.

Source: ESE, 1996.
-------
The risk results of the current worker scenario indicate that the total potential risk
associated with potential worker exposure to carcinogenic COCs in soil is within USEPA's
acceptable risk range of 1.0x10 -6 to 1.0x10 -4 for each of the seven study area evaluated. In
addition, the total His for non-carcinogenic COCs at each study area was less than one.

The current and future worker and future recreational scenarios were evaluated in the expanded
risk assessment. The soil exposure assumptions used for the BRA were also used for these
scenarios. Based on the results of the expanded risk assessment, there were no predicted
unacceptable risks from soils. The results of the expanded risk assessment are summarized in
Table 6-7.

6.5 Ecological Risk Summary

The potential for adverse effects to land animals, as well as sensitive ecological habitats, was
also investigated during the BRA and the expanded risk assessment. The potential for
accumulation within the food chain (bioaccumulation) was evaluated by comparing results from the
RI to reference values obtained from published literature.

The BRA guantified risks from the soils in the Soil/Source OU to large and small animals under
current and future exposure scenarios. The principal ecological exposure pathways evaluated
under current use scenarios in the BRA included:

• Exposure of land animals to COCs as a result of direct contact (incidental ingestion
and skin contact) with surface soil and food; and
• Exposure of land animals to COCs as a result of inhalation of dusts.

The principal ecological exposure pathways evaluated for future use scenarios in the BRA
included agricultural use (production of cattle, poultry, and crops). In addition, the use of
shallow groundwater for production of livestock and crops was also evaluated in the BRA under
the future use scenario. This exposure pathway will be discussed further in the ROD for the
groundwater OU.

The expanded risk assessment evaluated risks posed to ecological receptors by discharge of the
shallow groundwater to surface water at the seven study areas. The expanded risk assessment did
not evaluate additional exposure scenarios involving exposure of ecological receptors to soil.
The ecological risk results will be discussed in the ROD for the Groundwater OU.

No unacceptable ecological risks from soils were predicted in the BRA or the expanded risk
assessment.

7.0 Description of the No Further Action Alternative

Based on the careful consideration of the technical, environmental, institutional, public
health, and cost criteria as presented in Section 6.0, and in keeping with the overall response
strategy, the recommended remedial action alternative for the LAAP Soil/Source Operable Unit is
No Further Action.

As approved by USEPA and LDEQ, an IRA was conducted from 1987 through 1990. The IRA activities
included excavation and treatment of lagoon sediments and soils by incineration, and capping of
-------
the lagoons. No explosive chemicals above 100 mg/kg were detected in any soil samples collected
at Area P after completion of the IRA. The cost of the IRA was approximately $30,000,000.

CERCLA, as amended by SARA, suggests that a remedial action should be selected "that is
protective of human health and the environment, that is cost effective, and that utilizes
permanent solutions and alternative treatment technologies or resource recovery technologies to
the maximum extent practicable." However, the NCP recognizes that there are situations where no
further action is appropriate. The NCP states no-action alternative may be appropriate where a
removal or remedial action has already occurred at a site" (55FR8715). The study areas are not
close to population centers and the projected future industrial land use of the installation
reduces the likelihood of exposure to soil/source areas.

The results of the BRA indicated that, for the future residential use scenario, soil at BG-5,
BG-8 Landfill/Lagoon, and LF-3 may pose slightly elevated non-carcinogenic risks (His of 1 to
3). An expanded risk assessment was conducted as part of the FS to reflect the fact that LAAP
will remain industrial and will not be used for residential or agricultural use (refer to
Section 4.0 of this document for a description of the expanded risk assessment). This expanded
risk assessment showed that under a worker exposure scenario, potential risks to human health
are within the acceptable range.

Existing Army regulations and protocol make the sale of the LAAP property unlikely (refer to
Section 2.0 of the FS, Future Use of LAAP). Furthermore, CERCLA Section 120(h)(3)(B) reguires
that if the property is sold or transferred, each deed must contain language stating that action
to protect human health and the environment has been taken before the date of property transfer.
In addition, Louisiana State Statute (LSA) R.S. 30:2039 reguires that a notice of hazardous
waste shall be recorded into the mortgage and conveyance records of each parish where the
property is located. The Army will retain control of LAAP, and access to the installation will
remain restricted in the future.

Given the installation-specific conditions discussed above, combined with the numerous
regulations governing the transfer of LAAP property, No Further Action would be protective of
human health and the environment. Therefore, No Further Action is the recommended remedial
alternative for the LAAP Soil/Source OU.

The objectives of remedial actions for the Soil/Source OU include the protection of the
groundwater and prevention of direct contact with Area P soils. The IRA at Area P addressed
these objectives by removing chemical constituents from the soils, lagoon water, and wastewater.
The studies undertaken at LAAP have shown that no potential human health or environmental risks
are associated with the soils/sources at the other six study areas; therefore, there are no
remedial action objectives associated with other study areas.

If in the unlikely event the property was to be transferred in the future, and a worker exposure
scenario would no longer be appropriate, then the Army would readdress potential risks based on
the use scenario.

8.0 Documentation of Significant Charges

The Proposed Plan for the LAAP Soil/Source OU was released for public comment on January 8,
1996. The Proposed Plan identified No Further Action as the Preferred Alternative. The DA
has reviewed all written and verbal comments submitted during the public comment period. Upon
review of these comments, it was determined that no significant changes to the remedy, as it was
originally identified in the Proposed Plan, were necessary.
-------
9.0 References

Burroughs, D. July 23, 1991. Personal Communication with Claire Marcussen, Environmental Science
& Engineering, Inc., Gainesville, FL, re: Worker exposure at the LAAP study areas. Thiokol
Corporation, Louisiana Division.

Hawley, J.D. 1985. Assessment of health risks from exposure to contaminated soil. Risk Anal.
5(4) :289-302.

Ryan, E.A., Hawkins, E.T., Magee, B., and Santos, S.L. 1987. Assessing risk from dermal exposure
at hazardous waste sites. In: Proceedings of the 8th National Superfund Conference. Hazardous
Materials Control Research Institute, Silver Spring, MD.

Thiokol Corporation. 1987. Ambient Air Quality Assessment for Louisiana Army Ammunition Plant
(LAAP). Preliminary Report Number 43-21-0527-87. Louisiana Division, Shreveport, LA.

Thiokol Corporation. 1990. Standard Operating Procedures. Revision Number 1. SOP Number
LP-OOOO-H-03. Louisiana Division, Shreveport, LA.

U.S. Environmental Protection Agency (USEPA) . 1984. Health Effects Assessment for Lead.
Environmental Criteria and Assessment Office, Cincinnati, OH. PB86-134665. EPA/540/1-86/055.

U.S. Environmental Protection Agency (USEPA). 1985. Development of Statistical Distributions or
Ranges of Standard Factors Used in Exposure Assessments. Office of Health and Environmental
Assessment, Office of Research and Development, Washington, DC. EPA/600/8-85/010.

U.S. Environmental Protection Agency (USEPA). 1988. Superfund Exposure Assessment Manual (SEAM).
Office of Remedial Response, Washington, DC. EPA/540/1-88/001.

U.S. Environmental Protection Agency (USEPA). 1989. 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 (USEPA). 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.
-------
GLOSSARY OF TERMS

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

Aquifer: A layer of soil or rock that can supply usable quantities of qroundwater. Aquifers can
be used as a source of water for drinkinq, irriqation, and industrial purposes.

Risk Assessment: The process whereby risks to human health and the environment are
quantitatively evaluated. This information is used to determine whether remedial actions are
necessary. The risk assessment is conducted durinq the RI/FS.

Berm: A narrow barrier used to keep liquids from flowinq into or out of an enclosure.

Carcinoqenic: Term used to describe chemicals or substances that are known or suspected to
cause cancer in humans based on observed health effects in humans or existinq data from animal
laboratory tests.

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

Constituents of Concern (COCs): Site-related chemicals that pose critical health concerns to
environmental receptors because of their toxicity and potential for exposure. Althouqh many
chemicals at a site may pose a risk to human health and the environment, COCs represent those
constituents that contribute the majority of risk.

Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA): A federal law
enacted in 1980 and subsequently modified by the Superfund Amendments and Reauthorization Act of
1996 (SARA). This act resulted in the creation of a trust fund, commonly known as "Superfund,"
which provides money to investiqate and clean up abandoned or uncontrolled hazardous waste
sites. In the case of federal facilities such as LAAP, the Army is responsible for financinq the
investiqation and cleanup activities.

Ecotoxicity Quotient (EQ): A value used to evaluate the potential for adverse effects on
environmental receptors. The EQ relates concentrations of chemicals of concern in the
environment to establish benchmark concentrations.

Explosive Chemicals: Chemicals which are used to manufacture explosive devices such as
bombs and mines.

Exposure Pathways: The routes by which chemicals reach receptors. These routes may include
(for example) the route of transport from the soil to the surface water to recreational use by
people, and thus exposure to the chemical.

Feasibility Study (FS): A study that supports the selection of a remedial action at an NPL site.
The FS identifies, develops, and evaluates several alternatives for addressinq contamination.

Geoloqic Unit: A rock/soil mass classified as a qroup based on shared characteristics of the
rocks and soils.

Groundwater: Water that is present in the open spaces between soil particles (silt, sand,
qravel) and/or rock fractures below the qround surface.
-------
Hazard Index (HI): An indicator of the potential for a hazardous substance to cause noncancerous
health effects in humans. The HI is calculated by dividing worst-case human exposure estimates
to a particular substance by exposure levels that USEPA has determined to be acceptable. If the
result of this calculation is greater than 1.0, there may be concern for potential non-cancer
effects. As a rule, the greater the value above 1.0, the greater the level of concern.
Hydrogeology: The study of groundwater and aquifers.

Hydrogeologic Unit: A geologic unit that contains groundwater.

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

Interim Remedial Action (IRA): Removal or remedial actions that are taken to respond to an
immediate site threat or to take advantage of an opportunity to significantly reduce risk
guickly.

Landfarm: A common method of treating soils and sludges where the soil/sludge is spread out in
an open area in order to allow air and sunlight to reach the soil/sludge. This method allows
naturally occurring degradation processes (such as biodegradation) to occur more easily.

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

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

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

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

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

Pink Water: Pink water is the waste water created as a result of explosive manufacturing
operations. The water is pink or red, and the color is caused by the presence of explosive
chemical.

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

Receptor: A human, animal, or plant that could potentially receive exposure to chemicals
resulting from the chemicals migration from hazardous waste sites.

Record of Decision (ROD): A legal document that describes in detail the remedy selected for an
entire NPL site or a particular operable unit. The ROD summarizes the results of the RI/FS and
includes a formal response to comments supplied by the public.
-------
Reference Dose (RfD): The daily acceptable level of constituents of concern intake. This
number is used to estimate potential for non-carcinogenic effects.

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

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

Responsiveness Summary: Comments presented during the public meeting and received during the
public comment period that are considered and addressed by the Army.

Risk Assessment Guidance for Superfund (RAGS): A document produced by the USEPA as a guide for
conducting risk assessments under Superfund.

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

Source Areas: The areas where waste was once handled (treated, stored, disposed of, etc.) which
later acts as a source for contaminants.

Superfund Amendments and Reauthorization Act of 1986 (SARA): This act modified CERCLA and
resulted in the creation of a trust fund commonly known as "Superfund" which provides money to
investigate and cleanup abandoned or uncontrolled hazardous waste sites.

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

Volatile Organic Compounds (VOCs): Organic liguids that readily evaporate under atmospheric
conditions and exhibit varying degrees of solubility in water. Examples of VOCs detected at LAAP
include trichloroethylene (TRCLE) and tetrachloroethene (PCE).
-------
Appendix A
Responsiveness Summary

LAAP SOILS/SOURCE OPERABLE UNIT RESPONSIVENESS SUMMARY

Summary of Comments Received During the Louisiana Army Ammunition Plant Soil/Source Area Operable Unit Public
Meeting Held on January 25, 1996

A number of comments were received from the community during the public meeting for the LAAP Soil/Source OU,
held on January 25, 1996. With one exception the comments were received during the availability session prior
to the start of the meeting. Comments received during the availability session were written on notecards. The
one oral guestion received during the public meeting was transcribed by the court recorder.
The following is a summary of the guestions and responses.
and
Comment 1 What are the standards for chemicals in groundwater?

Response: The federal government publishes standards for the maximum allowable levels of certain
chemicals in drinking water. These standards are called Maximum Contaminant Levels (MCLs)
generally apply to underground sources of drinking water. There are no MCLs for explosive
compounds in groundwater. Therefore, cleanup standards for explosive compounds in the
groundwater at LAAP will be determined on the basis of a risk assessment, as appropriate.

Comment 2 What type(s) of chemicals are in the explosives?

Response: The primary explosive compounds used at LAAP were TNT, RDX, and HMX which stand for
trinitrotoluene, Research and Development Explosive, and High/Melting Explosive, respectively.
The actual chemical names for RDX and HMX are cyclotrimethylenetrinitramine and
cyclotetramethylenetetranitramine. There are also several by-products of TNT present in the
soils at LAAP. These compounds belong to a family of chemicals referred to as nitroaromatics. A
more complete discussion of these chemicals is available in the RI Report published by ESE.

Comment 3 (What are the) concentrations of explosives in Area P groundwater?

Response: The concentrations of explosive compounds in the groundwater at Area P have varied over the 12
years that data have been collected. In 1990, concentrations of RDX ranged from below detection
limits (BDL) to 19 milligrams per liter (mg/L). HMX ranged from BDL to 1.02 mg/L. TNT ranged
from BDL to 16.4 mg/L. A more complete history of the concentrations of explosive compounds in
the groundwater is available in Section 6.0 of the RI Report.

Comment 4 Is groundwater (contaminated) leaving the plant boundary?

Response: There are currently no data showing that contaminated groundwater is leaving the plant
boundary. However, further evaluation is needed before the Army can state conclusively that
chemically affected groundwater is or is not leaving the plant boundary. For this reason, the
investigation at LAAP has been split into two Operable Units (OUs) consisting of the
Soil/Source OU and the Groundwater OU. This split will allow the Army to pursue final action
regarding the soil without waiting for the groundwater issues to be resolved. The Army is
currently in the process of identifying information needs and issues with respect to the
Groundwater OU so these issues can be addressed.
-------
Appendix B

Administrative Record Index

EPA ADMINISTRATIVE RECORD
LOUISIANA ARMY AMMUNITION PLANT
Shreveport, Louisiana

April 1996
Doc
No. Date

1 May 1978
September 1979
- March 1980
March
1982
Author

Dept. of the Army,
Office of the Project
Manager for Chemical
Demilitarization and
Installation
Restoration, Aberdeen
Proving Ground, MD

United States Army
Environmental Hygiene
Agency, Aberdeen
Proving Ground, MD
Envirodyne Engineers,
Inc.
12161 Lackland Road
St. Louis, MO 63141
Recipient(s)

LAAP
Title/Description

Installation Assessment of
Louisiana Army Ammunition Plant
(LAAP), Record Evaluation Report
No. 120
Pages

108
Commander, U.S. Army
Materiel Development and
Readiness Command

HODA (DAEN-MPO-U)
HGDA (DAEN-ZCE)
Superintendent, Academy
of Health Sciences
(HSA-IPM).

LAAP
P.O. Box 30058
Shreveport, LA 71130

Commander, U.S. Army
Toxic and Hazardous
Materials Agency
(USATHAMA)
Aberdeen Proving Ground, MD
Geohydrologic Consultation No. 31-
24-0152-80, LAAP, Shreveport.
Louisiana
26
LAAP, Geotechnical Report
Interim Report Number 2
197
-------
May 15, 1982
Envirodyne Engineers,
Inc.
LAAP

Commander, USATHAMA
LAAP,
Contamination Analysis Report
343
September 30,
1982
October 15,
1982
June 1986
Envirodyne Engineers,
Inc.
Envirodyne Engineers,
A.T. Kearney, Inc.
Alexandria, VA and

Harding Lawson
Associates, Houston.
Texas
LAAP

Commander, USATHAMA

LAAP

Commander, USATHAMA

EPA Region VI
LAAP, 145
Final Report
Analysis of Alternative Measures 20
Preliminary Assessment 131
LAAP
Shreveport, Louisiana
LAO 21382053
December 19,
1986
Environmental Science
& Engineering, Inc.
(ESE)
USATHAMA, Assessments
Division, Aberdeen
Proving Ground, MD
Remedial Investigation at LAAP,
Final Report A011
Volume II--Appendices
Part A
182
9 December 19,
1986
ESE
USATHANA
Remedial Investigation at LAAP,
Final Report A011
Volume II--Appendices
Part B
240
10 January 30,
1987

11 August 1987

12 May 1978
ESE

U.S. Army

IT
USATHANA

Public

USATHAMA
Remedial Investigation at LAAP,
Final Report A011

Public Notice of Interim Response

Interim Response Action (IRA)
Remedial Investigation (RI), Area
P Lagoons
175
-------
13 August 1987

14 August 1987

15 October 1987

16 December 1987

17 December 1987
18 December 4,
1987
19 December 7,
1987
20 December 1987
21 February 1988
IT
International
Technology
Corporation (IT)

IT
IT
LDEQ and U.S. Army
IT
IT
IT
IT
USATHAMA
USATHAMA
LAAP
USATHAMA
Internal
Louisiana Department of
Environmental Quality
(LDEQ) and

U.S. Environmental
Protection Agency (EPA)
Region VI

LDEQ and EPA Region VI
LDEQ and EPA Region VI
LAAP
Feasibility Study, Final Sampling
and Analysis Plan

Interim Response Action (IRA),
Feasibility Study, Area P Lagoons
Public Involvement and Response
Plan, Interim Response Action -
Area P Lagoons

Interim Response Action (IRA)
Decisions Memorandum, Area P
Lagoons

Decision Memorandum for Interim
Response action at Area P

Installation Restoration
Incineration Program Description
Interim Response Action, Part 1,
Remedial Action Plan
Installation Restoration
Incineration Program Description
Interim Response Action, Part 2,
Incineration Plan

Installation Restoration
Incineration Program Description
Interim Response Action, Part 3,
Trial Burn Data

Public Involvement and Response
Plan, Interim Response Action,
Area P Lagoons
170
36
145
155
154
35
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22 April 11, 1988

23 June 8, 1988

24 June 8, 1988
25 June 8, 1988
26 June 8, 1988
27 July 26, 1988
28 September 1988
29 September 1988
LDEQ

IT, LAAP

IT, LAAP
LAAP

LDEQ

LDEQ
IT, LAAP
LDEQ
IT, LAAP
Office of Health
Assessment, Agency
for Toxic Substances
and Disease Registry
(ATSDR)

IT
Weston, Inc.
LDEQ
LAAP
LAAP
USATHAMA
Demand for Action

Remedial Design/Remedial Action
(RD/RA) , Volume I: Work Plan,
Interim Remedial Action at LAAP
Area P Lagoons

RD/RA Work Plan, Volume II:
Appendix A, Safety, Health and
Emergency Response Plan, Interim
Remedial Action at LAAP Area P
Lagoons

RD/RA Work Plan, Volume III:
Appendix B, Spill Prevention,
Control, and Countermeasure Plan,
Interim Remedial Action at LAAP
Area P Lagoons

RD/RA Work Plan, Volume IV:
Appendix C, Quality Assurance
Project Plan, Interim Remedial
Action at LAAP Area P Lagoons

Preliminary Health Assessment
Revised Public Involvement and
Response Plan, Interim Response
Action, Area P Lagoons

Task Order - 8, Field
Demonstration - Composting of
Explosives - Contaminated
Sediments at LAAP
10

25
350
35
300
35
40
-------
30 October 1988
31 January 1989
32 January 31,
1989

33 February 10,
1989
34 February 21,
1989
35 April 1989

36 July 1989

37 October 1989

38 May 1990

39 May 1990

40 May 1990
IT
LDEQ
EPA, LAAP, LDEQ
Weston
Hunter/ESE
LAAP
ESE
ESE
LAAP
Commander, LAAP
Robin Lyn Stein LAAP
USATHAMA

EPA, U.S. Army, LDEQ Internal
Public
USATHAMA
USATHAMA
USATHAMA
USATHAMA
USATHAMA
Evolutionary Enhancements to the 35
HTTS-1

Letter granting permission to 2
incinerate soil

Post Remedial Investigation, 9
Resampling Effort

Federal Facility Agreement (FFA) 83
between the U.S. EPA, U.S. Army,
and LDEQ

News Release regarding EPA, U.S. 4
Army, and LDEQ signing a Federal
Facility Agreement for federal
Superfund cleanup activities at
LAAP

Delivery Order 8, LAAP, Updated 600
Remedial Investigation (Two
volumes)

Public Involvement and Response 130
Plan for LAAP

Proposal to Revise the Excavation 45
Criteria for the LAAP Area P
Interim Response Action

Feasibility Study, Final Sampling 120
and Analysis Plan, Data Item A004

Feasibility Study, Final Sampling 125
and Analysis Plan, Volume 2,
Quality Assurance Project Plan,
Data Item A006
ESE
USATHAMA
Feasibility Study, Final Health
and Safety Plan, Data Item A009
100
-------
41 May 1990
42 August 2, 1990
43 January 10,
44 July 3, 1991
45 September 1991

46 February 1992

47 February 1992
ESE
USAGE, Fort Worth
District and Toxic
and Hazardous
Materials Agency

Engineering
Technologies
Associates, Inc.
Chemical Hazard
Evaluation Program,
Health and Safety
Research Division,
Oak Ridge National
Laboratory

ESE
ESE
ESE
48 September 1992 USATHAMA

49 September 1992 IT
USATHAMA
Commander, LAAP
USATHAMA
USATHAMA
USATHAMA
USATHAMA
USATHAMA
LAPP
USATHAMA
Feasibility Study, Final 165
Feasibility Study Work Plan, Data
Item A005

Closure Plan for the Interim 45
Response Action at the Area P
Lagoons
Technical Support Services for 145
Installation Restoration Program,
Contract DAAA15-89-D-0009, Task 2
- Prepare Ground Water Model for
Selected Sites at the Louisiana
Army Ammunition Plant - Final
Report
Assessment of Applicable or
Relevant and Appropriate
Reguirements (ARARs) for LAAP
Maintenance Plan, LAAP, Former
Area P Lagoons

Final Report on Decontamination
Operations (Area P)
100
LAAP Proposed Basis for the 12
Feasibility Study

Feasibility Study, LAAP, Final 1700
Comprehensive Remedial
Investigation, Vol. 1 through 7

Feasibility Study, LAAP, Final 300
Comprehensive Risk Assessment,
Volumes 1 and 2
14
94
-------
50 October 1992
51 January 1993
52 January 1993
Department of the
Army
Woodward/Clyde
Federal Facilities
Woodward/Clyde
Federal Facilities
United States Army
Materiel Command,
Alexandria, Virginia
U.S. Army Environmental
Command (USAEC)
USAEC
53 October 1993
54 February 1994
55 February 1994
56 February 1994
USAEC
Science Applications
International
Corporation (SAIC)
SAIC
SAIC
57 February 1994 SAIC

58 February 1994 SAIC
ESE
U.S. Army Environmental
Command (USAEC)
(formerly USATHAMA)
USAEC
USAEC
USAEC
USAEC
Environmental Assessment, Proposed
Inactivation of the LAAP
Shreveport, Louisiana and of the
Scranton Army Ammunition Plant,
Scranton, Pennsylvania

Final Technical Work Plan, LAAP
Drinking Water Monitoring,
Volume I

Final Technical Remedial
Investigation Work Plan,
Management and Resource
Utilization Plan, LAAP
(Volumes II, III, IV)

Revised Final Feasibility Study
Report for LAAP, Shreveport,
Louisiana

Final Data Management Plan, Five-
Year Review of Interim Remedial
Action at Former Area P Lagoons,
LAAP, Shreveport, Louisiana

Final Accident Prevention Health
and Safety Plan (Five-Year Review
of Interim...)

Final Quality Assurance Project
Plan (Five-Year Review of
Interim...)

Final Project Management Plan
(Five-Year Review of Interim...)

Final Field Sampling Design Plan
(Five-Year Review of Interim...)
130
29
600
325
30
80
100
35
145
-------
59 May 1994

60 May 1994

61 May 1994

62 March 1995

63 May 8, 1995

64 September 1995
65 December 5,
1995

66 December 1995
Woodward-Clyde
Federal Services,
Inc.

ESE
Geophex
EPA
ESE
Geophex, Ltd.
ESE
SAIC
USAEC
USAEC
USAEC
LAAP
USAEC
USAEC
USAEC
USAEC
67 Undated
brochures
USATHAMA
Public
Final, LAAP Drinking Water 25
Monitoring Report
Final Proposed Remedial Action 90
Plan

Final Technical Work Plan Addenda 17
for Drinking Water Monitor and
Monitor Well Abandonment at LAAP

Letter reguesting a single 1
groundwater unit for all of LAAP

Draft Soil/Source Operable Unit, 50
Proposed Remedial Action Plan

Final Report for Drinking Water 30
Monitoring and Monitor Well
Abandonment

Final Soil/Source Operable Unit, 30
Proposed Remedial Action Plan

Final Five-Year Review Report, 165
Five-year Review of Interim
Remedial Action at Former Area P
Lagoons

Notice of Public Hearing 4
-------
EPA ADMINISTRATIVE RECORD
LOUISIANA ARMY AMMUNITION PLANT
Shreveport, Louisiana

April 1996

Administrative Record Guidance Index
(EPA Guidance Documents are available for review at EPA Region 6, Ft. Worth, Texas)
Title Author Date
Remedial Action of Waste Disposal EPA 00/00/85
Sites (Revised), EPA/625/6-85/006

Guidance for Conducting Remedial EPA 00/00/88
Investigations and Feasibility
Studies Under CERCLA, EPA/540/6-89/004

Remedial Action Costing Procedure EPA 00/00/88
Manual, EPA/600/8-87-049

CERCLA Compliance with Other Laws EPA 08/00/88
Manual: Draft Guidance,
EPA/540/G-89/006

Guidance on Preparing Superfund EPA 10/00/88
Decision Documents: the Proposed
Plan, the Record of Decision,
Explanation of Significant
Differences, the Record of
Decision Amendment (Interim
Final)

Risk Assessment Guidance for Superfund: EPA 00/00/89
Volume I. Human Health Evaluation
Manual, Part A, Interim Final, OSWER
Directive 9285.7-01

Guidance for Conducting EPA 07/00/89
Remedial Investigations and
Feasibility Studies Under
CERCLA (Interim Final)

Role of Baseline Risk Assessment in EPA 00/00/91
Superfund Remedy Selection Decisions,
OSWER Directive 9355.0-30

Superfund Exposure Factors Handbook EPA 00/00/89

Water Well Regulations Louisiana DOT 00/00/85
-------
Appendix C

Letters of Support Agency Concurrence

(to be added)
-------