EPA/ROD/R10/94/097
February 1995
EPA Superfund
Record of Decision:
Umatilla Army Depot (Lagoons),
Operable Unit 7, Hermiston, OR
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~
DEFENSE ENVIRONMENTAL
RESTORATION PROGRAM
FINAL RECORD OF DECISION
UMA TILLA DEPOT ft. CTIVITY
.' EXPLOSIVES WASHOUT PLANT
OPERABLE UNIT
June 9, 1994
In accordance with Army Regulation 200-2, this document is intended by the Anny to
comply with the National Environmental Policy Act of 1969 (NEPA).
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Table of Contents
Ust of Figures and Tables 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 00 0 0 0 0 0 0 . . . . . . . 0 II
Acronyms and Abbreviations. 0 . 0 . . 0 . 0 0 . . . . . . . . 0 . . . 0 0 . 0 . 0 . 0 . . . . . 0 . . 0 . 0 III
1.0 Declaration of the Record of Decision 0 0 0 0 . . . . . . 0 . 0 0 . . 0 0 0 0 . . . 0 . . 0
1-1
2.0 Decision Summary 0'" 0 0 . . . . . . 0 . . . . . 0 . . 0 . . . . . 0 . . . . 0 . 0 0 0 . . . . 0 . . 0 2-1
2.1 Site Name, Location, and Description. . . . . . . . . . . . . . . . . . . . . .. 2-1
2.2 Site History and Enforcement Activities. . . . . . . . . . . . . . . . . . . . .. 2-4
2.3 Highlights of Community Participation. . . . . . . . . . . . . . . . . . . . .. 2-6
2.4 Scope and Role of Operable Unit. . . . . . . . . . . . . . . . . . . . . . . . ., 2-6
2.5 Site Characteristics. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-7
2.6 Summary of Site Risks. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-13
2.6.1 Human Health Risks. . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-15
2.6.2 Environmental Evaluation. . . . . . . . . . . . . . . . . . . . . . . . . .. 2-23
2.6.3 Remedial Action Criteria. . . . . . . . . . . . . . . . . . . . . . . . . . ., 2-24
2.7 Description of Alternatives. . . . . . . . . . .. . . . . . . . . . . . . . . . .. 2-26
2.8 SUmmary ofC.:>mparative Analysis of Al~~matives ............. 2-31
2.8.1 Tnreshold Criteria. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-31
2.8.2 Primary Balancing Criteria .......................... 2-32
2.8.3 Modifying Criteria. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-32
2.9 Selected Remedy. . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . .. 2-33
2.10 Statutory Determinations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 2-35
2.10.1 Protection of Human Health and the Environment. . . . . . . . ., 2-35
2.10.2 Compliance with ARARs .......................... 2-35
2.10.3 Cost-Effectiveness............................... 2-37
2.10.4 Utilization of Permanent Solutions and Alternative. . . . . . . .. 2-37
Treatment Technologies I)r Resource Recovery Technologies
to the Maximum Extent Practicable
2.10.5 Preference for Treatment as a Principal Element. . . . . . . . . .. 2-37
2.11 Documentation of Significant Changes. . . . . . . . . . . . . . . . . . . ., 2-38
3.0 Responsiveness Summary. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 . 3-1
Appendix A: Oregon DEQ Letter of Concurrence
Appendix B: References
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List of Figures and Tables
Figure
Page
2-1 Facility Location Map, Umatilla Depot Activity. . . . . . . . . . . . . . . . . . . . . 2-2
2-2 Location of Explosives Washout Plant and Washout Water Sump. . . . . . . . . 2-3
2-3 Explosives Washout Plant: Sample Locations and Analytical Results. . . . . . 2-10
for Wipe Samples
Table
Page
2-1 Chemici1 Analysis Results of Sludge in Washout Water. . . . . . . . . . . . . . . 2-8
Overflow Sump
2-2 Chemical Analysis Results from Standing Water in Washout. . . . . . . . . . . . 2-9
Water Overflow Sump
2-3 Analytical Results of Wipe Samples from Explosives Washout. . . . . . . . . . 2-11
Plant (Bldg. 489)
2-4 Physical and Chemical Properties of the Explosives. . . . . . . . . . . . . . . . . 2-14
2-5 Health Effects Criteria for Contaminants of Concern in the . . . . . . . . . . . . . 2-16
Explosives Washout Plant and Sump
2-6 Potential Carcinogenic and Noncarcinogenic Risks Due to ............ 2-19
Exposure to the Interior Building Surfaces of the Explosives
Washout Plant (Building 489) using Maximum Detected
Concentrations in Wipe Samples
2-7 Potential Carcinogenic and Noncarcinogenic Risks Due to . . . . . . . . '.' . . . 2-20
Exposure to the Interior Building Surfaces of the Explosives .
Washout Plant (Building 489) using 95 Percent UCL on Arithmetic
Mean of Concentrations in Wipe Samples.
2-8 Potential Carcinogenic and Noncarcinogenic Risks Due to .. . . . . . . . . . . . 2-21
Exposure to the Interior Building Surfaces of the Explosives
Washout Plant (Building 489) using 95 Percent UCL of .
Arithmetic Mean of Concentrations other than the Maximum Wipe
Sampks .
2..9 Preliminary Remediation Goals for the Explosives Washout Plant. . . . . . . . 2-22
(Building 489) Interior Building Surfac~s
II
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Acronyms and Abbreviations
AAP
ADA
AMCCOM
APe
ARARs
BACf
BRAC
.C
CAG
CERCLA
CPR
2,4-DNT
2,6-DNT
DNB
DaD
DRMO
oopp Kettle
DRE
EPA
EPIC
FFA
FS
HEAST
HI
Anny Ammunition Plant
Ammunition Demolition Activity
Armament, Munitions, and Chemical Command
Air pollution control
Applicable or Relevant and Appropriate RequirementS
Best available control technology
Base Realignment and Closure
Degrees Celsius
Carcinogen Assessment Group, EP A
Comprehensive Environmental Response,
Compensation, and Liabilitj Act
Code of Federal Regulations
2,4-Dinitrotoluene
2,6- Dinitrotoluene
1,3 -Dinitrobenzene
Department of Defense
Defense Reutilization and Marketing Office
Intermediate processing vessel between the explosive
. settling tank and pelletizer
Destruction and removal efficiency
U.S. Environmental Protection Agency
Environmental Photographic Interpretation Center
Federal Facility Agreement
Feasibility study
Health Effects Assessment Summary Tables
Hazard Index
III
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Acronyms and Abbreviations (continued)
HRS
I
High Melting Explosive (l,3,S,?-tettanitto-l,3,S,?-
tetrazacyclCtane)
Hazard Ranking System
HMX
Intake
ID
IRIS
Induced draft
LDso
Integrated Risk Infonnation System
Lethal dose to SO percent of the study population
LDR
M
Land disposal resttictions
Million
Ma..
~g/g
Maximum contaminant level
~
~g/sq em
mg/kg
MSL
Micrograms per gram (pans per million)
Micrograms per liter (parts per billion)
Micrograms per square centimeter
Milligrams per kilogram (pans per million)
Mean sea level
NAAQS
NB
National Ambient Air Quality Standards
Nitrobenzene
NEPA
NJDEP
National Oil and Hazardous Substances Pollution
Contingency Plan
National Environmental Policy Act
NCP
NPL
O&M
New Jersey Depanment of Environmental ProteCtion
National Priorities List
OAR
OOEQ
Operations and Maintenance
Oregon Administrative Rules
ORNL
Oregon Department of Environmental Quality
Oak Ridge National Laboratory
Iv
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Acronyms and Abbreviations (continued)
..
ORS
OSHA
Oregon Revised Statutes
Occupational Safety and Health Administration
OU
PHRED
Operable Unit
Public Health Risk Evaluation Data Base
ppm
ppb
Pans per million
Pans per billion
QAQ:,
Preliminary remediation goals
Quality Assurance/Quality Control
PRGs
RA
RAB
Risk assessment
RAC
RAG
Restoration Advisory Board (Fonnerly the Technical
Review Committee, TRC)
Remedial action criteria
RAGS
RAOs
Remedial action goal
Risk Assessment Guidance for Superfund
RCRA
RDX
Remedial action objectives
Resource Conservation and Recovery Act
Royal Demolition Explosive (l,3,5-trinitro-l ,3,5-
triazacyc1ohexane)
RID"
RI"
Reference dose
RIlFS
ROD
Remedial investigation
Remedial investigation/feasibility study
Record of Decision
RTECS
SARA
Registry of Toxic Effects of Chemical Substances
Superfund Amendments and Reauthorization Act
SF
Standard cubic feet per minute
Slope Factor (for risk assessment)
scfm
v
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Acronyms and Abbreviations (continued)
.
TBC
TCLP
To be considered
TSD
Toxicity characteristic leaching procedure
Treatment, storage, and disposal
Tetryl
TNB
N, 2,4,6- Tetranitro-N-methylaniline
1,3,5- Trinitrobenzene
TNT
TRC
2,4,6- Trinitrotoluene
UMDA
USATHAMA
Technical Review Committee (now called the
Restoration Advisory Board, RAB)
Umatilla Depot Activity
USAEC
U.S. Army Toxic and Hazardous Materials ngelh':y
U.S. Army Environmental Center (formerly
USA THAMA)
use
U.S. Code (Law)
vi
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1.0 Declaration of the Record of Decision
..
Site Name and Location
U.S. Anny Depot Activity, Umatilla
Explosives Washout Plant Operable Unit
Henniston, Oregon 97838-9544 .
Statement of Basis and Purpose
lIDs decision docwnent presents the selected remedial action for the Explosives Washout
Plant Operable Unit at the U.S. Anny Depot Activity, Umatilla (UMDA), at Hermiston,
Oregon, which has been 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 1986 (SARA), and. to the extent
practicable, the National Oil and Hazardous Substances Pollution Contingency Plan
(NCP). The decision is based on the administrative record for this site. Documents
contained in the administrative record are identified in Section 2.2.
The remedy WC1S selected by the U.S. Anny and the U.S. P.nvironmental Protection
Agency (EPA). The State of Oregon concurs with the selected remedy.
Assessment of the Site
Actual or threatened releases of hazardous substances from this site, if not addressed by
implementing the response action selected in this Record of Decision (ROD), may present
an imminent and substantial endangerment to public health, welfare, or the environment.
Description of the Selected Remedy
The purpose of this Washout Plant operable unit remedy is to eliminate the health and
environmental risks associated with the washout water sump and reduce the potential
safety/health risks associated with the Washout Plant building. The contaminated soils
around the Washout Plant will be remediated under the E~plosives Washout Lagoon
Soils operable unit and are not addressed in this ROD. .
The major components of the selected remedy include the following:
.
Oeanout and disposal of explosive waste sludge and contaminated washout water
from the washout water sump
Decontamination by flaming and landfill disposal of the concrete washout water
sump
Pretreatment of the Washout Plant process equipment (removal of asbestos
insulation, cleanup of pigeon droppings, and solvent flush)
Treannent by solvent wiping of galvanized steel siding and hot gas decontamination
of the aluminum siding, concrete, and process equipment
Removal and disposal of the process equipment
Demolition of the pelletizer building
.
.
.
.
.
1-1
1w.~0U6.FNI AOO.6'94
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'"
Statutory Determinations
The selected remedy is protective of human health and the environment and complies with
federal and state requirementS that are legally applicable or relevant and appropriate to the
remedial action. This remedy utilizes permanent solutions and alternative treatment
technologies to the maximum extent practicable, and satisfies the statutory preference for
remedies that employ treatment that reduces toxicity, mobility, or volume as a principal
element.
Because this remedy will not result in hazardous substances remaining on site above
health-based levels, the five-year review will not apply to this action and the site will not
require any long-term management or review due to total removal/destruction of
contaminantS of concern and hazard.
1-2
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Lead and Support Agency Acceptance 01 the Record 01 Decision
U.S. Army Depot Activity Umatilla
Explosives Washout Plant Operable Unit
SignatUre sheet for the foregoing Record of Decision for the Explosives Washout Plant
Operable Unit final action at the U.S. Anny Depot Activity at Umatilla betWeen the U.S.
Anny and the U.S. Environmental Protection Agency, with concurrence by the State of
Oregon Depanment of Environmental Quality.
~ ~- [J~
LeWIS D. Walker
Deputy Assistant Secretary of the Anny
(Environment. Safety, and Occupational Health)
913l:'/C;1
Dale
1-3
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Lead and Support Agency Acceptance of the Record of Decision
. U.S. Army Depot Activity umatllla
explosives Washout Plant Operable Unit (Cont'd)
;.
.
SignatUre sheet for the foregoing Record of Decision for the Explosives Washout Plant
Operable Unit final action at the U.S. Army Depot Activity at Umatilla betWeen the U.S.
Army and the U.S. Environmental Protection Agency, with concurrence by the State of
Oregon Department of Environmental Quality.
;f{&4Pffi~
Lieutenant Colonel Moses Whiteh 1, Jr.
Commander
U.S. Army Depot Activity, Umatilla
f!~9/f
1-4
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Lead and Support Agency Acceptance 01 the Record 01 Decision
U.S. Army Depot Activity Umatilia
explosives Washout Plant Operable Unit (Cont'd)
SignatUre sheet for the foregoing Record of Decision for the Explosives WaShout Plant
Operable Unit final action at the U.S. Army Depot Activity at Umatilla betWeen the U.S.
Army and the U.S. Environmental Protection Agency. with concurrence by the State of
Oregon Depanment of Environmental Quality.
~
~
-H/tfI1Y
Dale
alUck Clarke
Regional Administrator. Region 10
U.S. Environmental Protection Agency
'-5
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Lead and support Agency Acceptance of the Record Of DecIsion
. U.'S. Army Depot Activity Umatlila . .
explosives Washout Plant .Operable Unit (Coord)
"Sigll~tI.JI'C sheet for me foregoing Rccmd of Decision for the Explosives Washout Plant
Qpc:rab1e Umt.final ~on at the u.s. Army Depot Activity at Urnllln11a betwCCl the u.s.
Army and. the u.s. Environmental Prorectiou Agency, with eOI1CUIrencc by the Swc' of
Olqon Depanment ofEnvimDmcntal Quality. .
.1.>JJ.\-\e.~
Fred R~nW11
Dirb..b
0teg0D Depanmem ofEn~ta1 Quality
~Ul 2 6 1994
Dare
. .
Note: 1be Swa of Orecon', Lcm:z' of CoacaII'CDCC is IppCOded co this Record ofDc:c:ision.
. .
,-&
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Lead and Support Agency Acceptance of the Record of Decision
U.S. Anny Depot Activity Umatilla
Explosives Washout Plant Operable Unit (Cont'd)
Signature sheet for the foregoing Record of Decision for the Explosives Washout Plant
Operable Unit final action at the U.S. Army Depot Activity at Umatilla betWeen the U.S.
Army and the U.S. Environmental Protection Agency, with concurrence by the State of
Oregon Department of Environmental Quality.
';)~~l..~
Date
'-7
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2.0 Decision Summary
TIris Decision Sununary provides an overview of the problems posed by the conditions at
the UMDA Explosives Washout Plant (Washout Plant) building and sump, the remedial
alternatives, and the analysis of those options. Following that, it explains the rationale for
the remedy selection and describes how the selected remedy satisfies statutory
requirements.
2.1 Site Name, Location, and Description
The U.S. Anny Depot Activity at Umatilla is located in nonheastem Oregon in Morrow
and Umatilla Counties, approximately five miles west of Hermiston, Oregon, as shown
in Figure 2-1. The installation covers 19,729 acres ofland, of which 17,054 are owned
by the Anny and the remaining 2,675 acres are limited to agricultural use by restrictive
easement. The UMDA Explosives Washout Plant and sump (Site 5) are located in the
center of the UMDA installation, as shown in Figure 2-2.
The Washout Plant building, measuring about 100 feet by 32 feet, is located off Rir'
Road at the top of Coyote Coulee and to the east of the Explosives Washout Lgoc..s
(Site 4). The washout water sump (measuring about 10 feet by 18 feet by 7 feet in depth)
is located on the slope about half-way between the Washout Plant at the top of the Coulee
and the Explosives Washout Lagoons (Washout Lagoons) at the bottom of the coulee.
The poured concrete washout water sump has a total capacity of approximately 5,000
gallons. A sheet metal trough connects the Washout Plant building with the sump and the
sump with the Washout Lagoons. .
The Washout Plant building is constructed of poured concrete floors and structurai steel
and sheet metal siding and roofs. A concrr +e blast wall separates the building into two
smaller buildings, the washout building and recovered explosive pelletizing building.
Both buildings of the Washout Plant contain tanks, piping, and other process equipment
The washout building is in generally good structural condition while the pelletizer
building is in somewhat poorer structural condition. Both buildings could be secured
(locked) to prevent unauthorized access to the contaminated building interiors or process
equipment. The washout water sump is currently .open at the top which allows it to collect
rainwater which becomes contaminated and then overflows carrying contaminants to the
Washout Lagoons.
UMDA was established as an Anny ordnance depot in 1941 for the purpose of storing
and handling munitions. Access is currently restricted to installation personnel,
authorized contractors, and visitors. UMDA was included in the Department of Defense
(DoD) Base Realignment and Oosure (BRAC) program, which requires that the UMDA
conventional ordnance storage mission be transferred to another installation. Under this
program, it is probable that the Anny will eventually vacate the site; ownership could then
be relinquished to another governmental agency or private interests. Light industry is
considered to be the most likely future land use scenario based on the surrounding area,
but wildlife use is also being considered.
Northeastern Oregon, the setting for UMDA, is characterized by a semi-arid, cold desert
climate, an average ahnual precipitation of 8 to 9 inches, and a potential annual evapo-
2-1
"'.67062.Q.QU6.FNI ROD.&'9I
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I
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, .... EXPLOSIVE j
WASHOUT !
YATER SUMP
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UMAllUA Washout Plant ROD
DI\1[:
JAN. 1994
Figure 2-2: Location of explosive. Washout
Plant and Washout Water Sump
StM.[:
AS SHOWN
DIIC. HO.:
67062-044
1w.67C62-Q.O 1<.."" q()[).&91
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transpiration rate of 32 inches. The installation is located on a regional plateau of low
relief that consists of relatively penneable glaciofluvial sand and gravel overlying
Columbia River Basalt.
Ground water occurs primarily in tWo settings: in an unconfined aquifer within the
overlying deposits and weathered basalts. and in a vertical sequence of semi-confined and
confmed aquifers within the basalt. The depth to the unconfmed aquifer beneath the
Washout Plant is approximately 100 ft below grade. Ground water generally flows to
the nonh and northwest. but flow directions vary throughout the year since regional flow
gradients in the uppennost aquifer are influenced by irrigation. pumping, and leakage
from irrigation canals.
The Columbia River. approximately 3 miles to the north of the UMDA boundary, flows
from east to west; the Umatilla River. approximately 1 to 2 miles to the east. flows from
south to north. No natural streams occur within UMDA; the facility is characterized by
areas of closed drainage.
The region SUITOunding UMDA is primarily used for irriJ!;ated agriculture. The population
centers closest to UMDA are Hermiston (population 10.075), approximately 5 miles east;
Umatilla (population 3.032), approximately 3 miles northeast; and Irrigon (population
820). 2 miles northwest The total populations of Umatilla and Morrow Counties are
approximately 59.000 and 7,650. respectively.
Approximately 1,470 wells have been identified within a 4-mile radius ofUMDA. the
majority of which are used for domestic and irrigation water. Three municipal water
systems (Hermiston. Umatilla. and Irrigon) draw from ground water within a 4-mile
radius of UMDA. The Columbia River is a :najor source of potable and irrigation water,
and is also used for recreation. fishing, and the generation of hydroelectric power. The
principal use of the Umatilla River is irrigation.
2.2 Site History and Enforcement Activities
From the 1950s until 1965, UMDA operated an on-site Explosives Washout Plant similar
to that at other Anny installations. The plant processed munitions to remove and recover
explosives using a pressurized hot water system. The principal explosives consisted of
the following:
.
2.4,6-trinitrotoluene (TNT)
l,3,5-trinitro-l,3,5-triazacyclohexane (commonly referred to as Royal Demolition
Explosive or RDX).
.
.
1,3,5,7-tetranitro-l,3,5,7-tetrazacyclo-octane (commonly referred to as High
Melting Explosive or HMX) .
N,2,4,6-tetranitro-N-methylaniline (Tetryl)
.
2-4
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In addition, the munitions contained small quantities of 2,4-dinitrotoluene (2,4-DNT),
2,6-dinitrotoluene (2,6-DNT), 1,3,5-trinitrobenzene (TNB), 1,3-dinitrobenzene (DNB),
and nitrobenzene (NB), occurring as either impurities or degradation products of TNT.
Operation of the plant included periodic flushing and draining of the explosives washout
system. The wash water produced was discharged via an open metal trough through the
washout water sump to the two infiltration lagoons located to the northwest of the plant
The lagoons were constructed in the 19505 and used until 1965, when plant operations
and all discharges to the lagoons ended.
An initial installation assessment was perfonned in 1978 and 1979 to evaluate
environmental quality at UMDA with regard to the past use, storage, treatment, and
disposal of toxic and hazardous materials. Based on image analysis provided by EP A's
Environmental Photographic Interpretation Center (EPIC) as part of the assessment, the
Explosives Washout Lagoons (Site 4) were characterized as a potentially hazardous site.
In 1981, Battelle conducted an Environmental Contamination Survey and Assessment at
UMDA and identified what appeared to be a 45-acre plume of RDX in the shallow aquifer
underneath the lagoons. Battelle concluded that discharges to the lagoons had caused
contamination of the alluvial aquifer. Subsequent investigations confirmed the presence
of explosives in the soil and ground water.
In 1984, the Explosives Washout Lagoons were evaluated using EPA's Hazard Ranking
System (HRS) and received a score in excess of 28.5. As a result, the lagoons were
proposed for inclusion on the National Priorities List (NPL) in 49 Fed. Reg. 40320
(October 15, 1984) They were formally listed on the NPL in 49 Fed. Reg. 27620 (July
22, 1987) based on the HRS score and the results of the installation Resource
Conservation and Recovery Act (RCRA) facility assessment The Washout Plant was
included as Site 5 in the RCRA facility assessment
On October 31,1989, a Federal Facility Agreement (FFA) was executed by UMDA, the
Army, EP A Region X, and the oregon Department of Environmental Quality (ODEQ)
(USEPA et al, 1989). The FFA identifies the Army as the lead agency for initiating
response actions at UMDA. One of the purposes of the FF A was to establish a
framework for developing and implementing appropriate response actions at UMDA in
accordance with CERCLA, the NCP, and Superfund guidance and policy. Investigation'
and remediation of the lagoons and the Washout Plant were tasks identified within this
framework. A remedial investigation and feasibility stUdy (RI/FS) of the entire UMDA
ins~on, including the lagoons and the Washout Plant sites; was initiated in 1990 to
determine the nature and extent of contamination and to identify alternatives available to
clean up the facility.
The RI and Human Health Baseline Risk Assessment for UMDA were completed in
August 1992. An additional ris~ assessment was perfonned for the interior of the
-Washout Plant in 1993. For purposes of the FS, the Washout Lagoons Soils and
Washout Plant were each designated as separate operable units. The Washout Lagoons
Soils Operable Unit reached a Record of Decision in 1992, which specified excavation
and composting of all soils with TNT or RDX greater than 30 parts per million. The
feasibility stUdy for the Washout Plant was completed in December 1993, and the
proposed plan was completed in February 1994.
2-5
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2.3 Highlights of Community Participation
In 1988. UMDA assembled a Technical Review Conunittee (TRC) composed of elected
and appointed officials and interested citizens from the surrounding communities.
Quanerly meetings provide an opportunity for UMDA to brief the TRC on installation
environmental restoration projectS and to solicit input from the TRC. One TRC meeting
was held in January 1993 during preparation of the feasibility study for the Explosives
Washout Plant Operable Unit. In that meeting. the TRC was infonned as to the scope and
methodology of the Washout Plant remedial alternatives. Approximately 20 TRC
meetings have been held during the RIIFS of the Washout Plant and Washout Lagoons.
In December 1993. the TRC was changed to a Restoration Advisory Board (RAB) with
similar functions. Two RAB meetings have been held since.
The feasibility study and proposed plan for the Explosives Washout Plant Operable Unit
were made available to the public on February 15. 1994. at the following information
repositories: UMDA Building 32. Hermiston. Oregon; the Hermiston Public Library.
Hermiston. Oregon; and the EPA offices in Ponland, Oregon. The notice of availability
of the proposed plan was published in the Hermiston Herald. the Tri-City Herald. and the
East Oregonian on February 15. 1994. The public comment period ended on March 17.
1994.
A public meeting was held at the Armand Larive Junior High School. Hermiston.
Oregon, on March 2. 1994. to inform the public of the preferred alternative and to seek
public commentS. At this meeting. representatives from UMDA. the U.S. Army
Environmental Center (USAEC). EPA. ODEQ. and Arthur D. Little. Inc. (an
environmental consultant to USAEC) were available to answer questions about the site
and remedial alternatives under consideration. A response to commentS received at the
meeting and during the 3O-day commentperiod is included in the Responsiveness
Summary appended to this ROD.
2.4 Scope and Role of Operable Unit
Operable unitS are discrete actions that constitute incremental steps toward the final .
overall remedy. Operable ,units can be actions that completely address a geographic
portion of a site or specific problems. or can be one of many actions that will be taken at
the site.
The Washout Plant Operable Unit consistS of two major explosive contaminated items.
the Washout Plant building and the washout water sump (and trough).
Some of the soil around the Washout Plant and under the washout water trough has also
been found to be contaminated with explosives as the result of outdoor storage of old
plant equipment, explosives tracked out oCthe building on employees' shoes and leakage
or overflow from the washout water trough. This contaminated soil will not be treated as
part of this operable unit but will be remediated as part of the Explosive Washout
Lagoons Soil Operable Unit The estimated quantity of this soil is approximately 500
cubic yards. which will not significantly increase the amount of soil already included
within the Washout Lagoons Soil Operable Unit (4.800 cubic yards).
2-6
-------
Although ground water in the vicinity of the Washout Plant has explosives
contamination, it is thought to be due to disposal of wastewater in the Washout Lagoons.
Thus, ground water remediation is not addressed in this ROD, since this remedy is
intended to address exposure to the Washout Plant building and washout water sump.
Ground water in the vicinity of the Washout Plant and lagoons is a separate operable unit
with a separate FS, proposed plan, and ROD.
2.5 Site Characteristics
The original source of contamination at the Explosives Washout Plant Operable Unit was
the spillage of explosives inside and around the plant and disposal of explosives-
contaminated wash water through the trough and sump to the lagoons. No other
contamination sources are suspected based on records of past activities. The type of
contamination is explosives compounds (primarily TNT and RDX), and their
manufacturing by-products and environmental breakdown products.
Presently, the primary source of any further soil or ground water contaminatio&1 from this
site is the washout water sump. Rainwater, which can enter the open top sump directly or
by way of the open washout water trough, becomes contaminated with explosives from
the sludge in the sump and then overflows to the Washout Lagoons. The sludge in the
sump also contains sufficient explosive (up to 70 percent by weight. TNT) to
be detonated (Anhur D. Little, 1987b). thus posing a safety hazard Table 2-1 presents
the analyses results for samples of sludge from the sump,.and Table 2-2 presents
analyses results of water samples from the sump.
Some of the soil around the Washout Plant and washout water sump has become
contaminated with explosives. but this soil will be treated by a composting process along
with the soil from the washout lagoons under the Explosives Washout Lagoons Soils
Operable Unit to meet the remedial action criteria of 30 ppm or less of TNT and RDX
(U .S. Army IR Program. 1992).
Ten wipe samples were taken from the inside surfaces of the Washout Plant building
during the remedial investigation (Dames and Moore, 1992b). Four explosives (TN[,
HMX. RDX. and TNB) were found to be present at concentrations ranging from less
. than 0.02 J.1g/sq em to 17.6 J.1g1sq em. Locations of the wipe samples are described below
and shown in Figure 2-3. The analytical ~sults are summarized in Table 2-3.
.
PS-l: Sample collected on the floor below the easternmost washout tank near the
drainage valve. Possible spillage of contaminated water or water seepage from the
drainage holes may have occurred here when the valves were changed or cleaned. or
when the valve bladders were clogged.
P5-2: Sample collected from the side of the washout tank below possible overflow
area. Slight staining was observed on the metal tank wall in this area.
.
.
P5-3: Sample collected on the floor below the westernmost washout tank near the
drainage valve in a slight depression in the floor. This sample was collected for the
same reason described for P5-1.
2.7
-------
Table 2.1: Chemical Analysis Results of Sludge In Washout Water Overflow Sump
Sample. Sample Comparison
. D4-1 D4.2 Criteria
(~gIg). (~g/g). (~g/g).
Explosives
1,3,5- TNB 210 370 NSA
1,3-DNB LT50 LT50 NSA
2,4,6- TNT 400000 710000 NSA
2,4-DNT LT42 780 NSA
HMX 150 LT67 NSA
Nitrobenzene L T 240 LT 240 NSA
RDX 1800 870 NSA
N
. 402,000
Q) Total Explosives 712,000
Other Inorganlcs
Nitrate/Nitrite 18 3.33 9.9
LT = Less Than .
* 1~g/g = 1 ppm by wt
NSA = No Standard Available in Media Analyzed
I
f
~
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Table 2-2: Chemical Analysis Results from Standing Water In Washout Water Overflow Sump
Sample Sample Comparison
W4-1 W4-2 Criteria
(~gJL)* (~g/L)* (~gJL)*
Explosives
1.3.5- TNB L T 0.626 1.18 NSA
2.4.6- TNT 5.67 8.35 NSA
HMX 8.87C 7.78C NSA
RDX 81.0C 16.1 C NSA
. Total Explosives 99.5 33.4
Othe.r Inorganlcs
N Nitrate/Nittite 280 550 NSA
.
CD
L T = Less Than
NSA = No Standard Available C = Confmned Result in
in Media Analyzed Second HPLC Column
. 1 ~g/L = 1ppb by wI.
Source: Remedial Investigation Report. Umatilla Depot Activity (Dames & Moore. 1992b)
i
i
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N
.
...
o
J
,
i
~
I
,i
&.9
-~
!o
0.
~ E
~J
"09
1;;
d
t
.... ,,'1'0.024
ne .. U~OI.
"" .. ...
"I . 1."
IDI .. 17.1
P~-6
(on ceiling
beam
- ... U~UI
P!i-4
(In trough
bela. .an)
Drying O.en
Chute 'rom
Penet Water
Separator
Penet/water
Scr.en Sepalatar
Chute to
Drying Oven
o
~-o
ZfT'I
Or
r
o~
~
Z 0.304
~
\::Y
P~-7 ,,: ~'=.
(an tap 01 .... - ,"'-
Shaker/Oven)- - ,......
~ PS-8 (an llaor)
- .. LTO"
M'" '.J
.... .. "'0.0»
MIl .. oael
PS-9
(dulty
caiUn,
beam)
011 ... O.aJ3
net .. 0.)4'
I11III .. 0,111
.. .. 0011
_... "TOM'
,., .. ..os
.. .. L1O.CW
.. .. l10,O:H
Q
SECOND
FLOOR
Saurce: Final RI Report (Dam.. and Moore. 1992b)
rl1\.(:
Ri.., to
Penetizing Plant
WASHOUT
APPARATUS TANK
FIRST
FLOOR
Riser from
Washout Tank
WER
Proce.. Equipment
Ventilation
System (Oucon Spray Scrubber)
..It,
JAN 1994
UMATILl.J\ Washout Plant
_. "'67062-013
~ Wipe Sample Lacatianl (ug/lq.cm.)
CRL TNT 0.023 uv/cm I
CRl ROX 0.029 ug/cm I
W1J
KML'
None
f'NI .. ,",,0.014
M .. 0.13'
.... ... 1.100»
IIJI-a.-
Washda.n and
Ov.rflo. Runoff! rough
P!i-J
(Belo. tank
an lloor)
@
VENT
"8 - lfa.OJ4I
,NY .. 0)01
.. - 0048
IIJI - O_I~I
CRl - C.rtified Reporting limit
l T = Leal Than
CRL THB 0.024 uv/cm I
CRL HIIX 0.033 uV/cm I
FlCURE 2-J: EXPLOSIVE WASHOUt PLAN!
-------
Table 2-3: Analytical Results 01 Wipe Samples From Explosives Washout Plant (Bldg. 489)
Sample No. . P5.1 P5.2 P5.3 P5.4 P5.5 P5.6 P5.7 P5-8 P5.9 P5.10
Location Floor near Side of Floor Under Washout Inside Top 0' Top 0' Floor near Top 0' Pelletlzer
Washout Washout Washout Water Washout Pelletizer Shaker Shaker Pelletizer Bldg.
Tank Tank Tank Overflow Tank Bldg. Oven Oven Bldg. Beam Vent
~gIsa. an Exolaslve Trough Beam
1, 3, 5 . TNB L T 0.024 LT. 0.024 L T 0.024 L T 0.024 LT 0.024 L T 0.024 LT. 0.024 L T 0.024 0.032 LT 0.024-
2,4.6 - TNT 0.256 LT 0.023 0.132 0.029 0.207 ~.400 0.304 2.700 0.349 0.030
HMX 0.049 L T 0.033 L T 0.033 L T 0.033 0.048 1.840 LT 0.033 L T 0.033 0.271 L T 0.033
RDX 0.304 0.338 0.084 LT. 0.029 0.151 17.600 LT 0.029 0.057 0.064 L T 0.029
L T = Lese than
N
.
...
...
Source: Final RI Report (Dames & Moore, 1992b)
f
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.
P5-4: Sample collected in the drainage trough below the south wall separating the
washout building from the pelletizer building. All drainage from the washout room
should have flowed through this trough.
P5-5: Sample collected from the comer of the hopper in the easternmost washout
tank. A fonner UMDA employee stated that residues that collected here were difficult
to remove by steam cleaning.
.
.
P5-6: Sample collected on a ceiling beam on the lower level of thepelletiiing
building. Pellet drying took place in this area, and a fonner UMDA employee
reponed that the room had been dusty during washout operations. The sample
location on the beam was discolored and dusty.
P5-7: Sample collected on top of the housing for the shaker dryer on the lower level
of the pelletizing building. This sample was collected near the drop chute leading
from the pellet water separator located on the second floor.
.
.
P5-8: Sample collected on the floor on the lower level of the pelletizing building.
This sample was collected near the drop chute that led from the pellet water separator
(second floor) to the shaker (ground floor). The drop chute consists of sheet metal
connected to the shaker dryer by a flexible seal. A fonner UMDA employee observed
what he believed to be pelletized Composition B explosives on the floor in this area.
P5-9: Sample collected on a ceiling beam on the upper level of the pelletizing
building. Pelletizing and water separation occurred on this level, and the room was
reponed to have been very dusty during operations.
.
.
P5-1O: Sample collected in a dust vent above the pelletizer.
All 10 of the wipe samples were detennined to contain one or more of the following
explosives (Table 2-3):
.
2,4,6- TNT
I,3,5-TNB
.HMX
RDX
.
.
.
Sample P5-9, collected on a ceiling beam on the upper level of the pelletizing building,
was the only sample to contain all four explosives. Pelletizing and water separation
occurred on this level, and the room was reponed to have been very. dusty during
operations. Wipe sample P5-6, also collected on top of a ceiling beam in the lower level
of the pelletizing building, contained the highest concenttations of three of the explosives.
The high concentration was likely due to the beam being very dusty and never (or rarely)
being cleaned. Pellet drying took place in this area, and the room was also reponed to
have been dusty during pelletizing operations.
During the RI, sampling was conducted for explosives on the exposed surfaces in the
Washout Plant, and contamination by several explosives was verified. An additional area
where larger concentrations of the explosives may possibly be found is inside the process
equipment and piping. The process equipment was steam cleaned following the close of
2-12
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the washout operations, but some explosives, possible at reactive levels, may remain in
the joints, corners, etc., of this equipment. To date no investigation has been perfonned
to detennine the extent of contamination remaining within the process equipment. The
assumption will have to be made, therefore, that the equipment is contaminated internally.
Since there is no potential hwnan health exposure pathway for this internal explosive
contamination, it is considered a potential explosion health or safety issue rather than a
toxicity or environmental contamination exposure issue.
Physical and chemical properties of the explosives are provided in Table 2-4. In general,
the explosives can be characterized as having relatively low aqueous solubility and low
volatility. Health effects criteria for the explosives, including carcinogenic data from EPA
databases. are presented in Section 2.6.
Potential routes for migration of the explosives include the following:
Air
If the washout water sump is left uncovered in place and/or the washout water trough il)
left ~ place, rainwater will continue to enter the sump and convey dissolved explosives to
the Washout Lagoons. Airborne transport of contmunated soil might then possibly
occur. Passive transport of the explosives from the sump (or lagoons) is very unlikely
because of the low volatility of the explosives.
There is little or no potential for air transport of the explosives on the inside building
smfaces or residual explosives contained within the process equipment inside the
Washout Plant. .
Surface Water
There is no potential for surface water transport of the explosives to the environment
from within the Washout Plant building or process equipment as long as the building is
maintained. In the case of the washout water sump. even if rainwater did continue to
flow through the washout water sump to the Washout Lagoons and convey further.
contamination to the lagoons. the lagoons are not located within a floodplain and there
would be no likelihood of surface water runoff from the lagoons. The low precipitation
rate and high soil permeability also make it highly unlikely that there could be any runoff
from the lagoons to contaminate surface waters.
Subsurface
Inflltration of precipitation and the overflow of water from th~ sump to the lagoons does
provide a potential subsurface pathway for migration. However. the rate of transport is
expected to be low due to the low precipitation and high evaporation rates in the region.
2.6 Summary of Site Risks
This section. summarizes the human health risks and environmental impacts associated
with exposure'to site contaminants and provides potential remedial action criteria.
2-13
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Table 2-4:
Physical and Chemical Properties of the explosives
N
.
~
..
I DNO" 1
. I I I I I i
TNT 2,ot.DNT 2,6.PNT TNB RDX IIMX T;tl}l
CAS Reeistry No. .. 118.96.7 \21.14.2 606.20.2 ".35-4 99.6.5.0 I,U2.4 2691...1.0 419-45.S
Empirical Formula " C7"~N]06 C,U6N,04; C,"6N204 C6H]N]06 C6H4N204 C]"6N,.O,. C4HANSOA c,lI~N~08
Molecular Weicht 227.1S I 82. IS .1821S 213.12 168.12 222.15 296.20 2B1, \1
Dcnsity (clcm3) 165 1.521 1.538 1.63 1.575 1.83 1.90(CI form) 1.13
Meltine Point (0C) 80.75 72 66 m 90 205 2B6 129.5
Vapor rressurc (mm He, 250C) 5.5..10.6 2.11110.4 5.67110.4 3.03lUr' 1.3..10.4 4.03110.9' 3.33110.14 5.69xIO.9
Aqueous Solubility (mc/L. 2.50C) ISO 210 206 385 533 60 5 80
Henry's Constant (atm.m3/mole. 2.50C) I.IOx10.8 1.86110.7 4.86110.7 UIIIO.9 .5.44x10.8 1.96110.11 2.6OxlO'1S 2.69xlO'"
LoC Ko\Y 2.00 1.98 1.89 1.18 1.49 0.87 0.26 \.65
K (mile) 1.00 0.68 0.21 2.23 0.45 0.21 0.44 0.7.\
R 4.46 3.34 1.72 8.71 2.5.5 1.73 2.51 3.46
Bio.concentnllon (actor (BCF) (fish) . 8.9.5 10.6 9.82 2.65 4.70 \.SO 0.49 6.31
Source: CHzM Hill. 1992. Table 2.3
~
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2.6.1 Human Health Risks
A baseline risk assessment was conducted by the Anny to estimate the risk posed to
human health by the Washout Plant building should it remain in its current state with no
remediation. The risk assessment consisted of an exposure assessment, toxicity
assessment, and human health risk characterization. The exposure assessment detailed the
exposure pathways (such as dust inhalation) that exist at the site for various receptors.
The toxicity assessment documented the adverse effects that can be caused in a receptor
as a result of exposure to a site contaminant.
The health risk evaluation used both the exposure concenttations and the toxicity data to
determine a Hazard Index (HI) for potential noncarcinogenic effects and a cancer risk
level for potential carcinogenic contaminants. In general, an ill of less than or equal to 1
indicates that even the most sensitive population is not likely to experience adverse health
effects. If it is above one, there might be a concern for adverse health effects. The degree
of concern typically correlates with the magnitude of the index if it is above one. The
cancer risk level is the additional chance that an exposed individual will develop cancer
over the course of a lifetime. It is expressed as a probability such as I x lQ-6 (1 in :-
million).
Risk assessments involve calculations based on a number of factors, some of which are
uncertain. First, the health effects criteria of specific chemicals are often based on limited
laboratory studies on animal species that are then extrapolated to humans. Further, the
exposure scenario requires estimation of the duration and frequency of exposure, the
identity of the exposed individual, and the contaminant concentration at the point of
exposure. If the value of the factor required for the risk assessment is uncertain, a -
conservative estimate is used so that a health-based exposure level or concenttation can be
calculated. For example, in order to calculate a reference dose for humans, toxicity
assessments divide doses observed to cause health effects in animals by an uncertainty
factor to account for species differences and human population variability. The
uncertainty factors for the explosives of concern are given in Table 2-5. In the case of
uncertainties associated with exposure scenarios, the most conservative plausible scenario
is selected. For example, in the New Jersey Department of Environmental Protection
(NJDEP) method (1992) for calculating human uptake of contaminants from surfaces by
a combination of three exposure pathways (dermal contact, dust inhalation and dust
ingestion), the same lifetime dosage (50% of the total weight of contaminant) of uptake is
assumed whether it is residential or industrial exposure. Since the number of hours
assumed for industrial exposure is much less than the number of hours for residential
exposure, the estimated uptake per hour for industrial exposure is greater, thereby posing
greater carcinogenic, -and non-carcinogenic risks. Therefore, industrial exposure was
assumed as the most conservative scenario for the risk assessment for this site.
Contaminants of concern in the UMDA Explosives Washout Plant Operable Unit were
identified as those explosives detected in the sump or on the building surfaces during the
site investigations. They were: -
. TNB
. TNT
. 2,4-DNT
. HMX
. RDX
2-15
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II)
.
~
en
rrable 2-5: Heelth Effects Criteria for Contaminants of Concern In the Explosives Washout Plant and Sump
Contaminant of Slope Factor Source Weight of CencerType Reference Source Critical Effect Uncertainty Confidence
Concern (mg/kg-d8y) Evidence DO.. (mg/kg- Factor Level
Class. day)
1,3,5- Increased
Trinitrobenzene 5.00E-05 IRIS splenic weight
10,000 Low
1:4;6- Unnarybladder Liver effects
Trinitrotoluene papillomas
0.030 IRIS C 5.00E-04 IRIS 1,000 Medium
Hepauc lesions
HMX 5.00E-02 IRIS 1,000 Low
Hepatocellular Inflammation 01
carcinomas and prostate
RDX 0.110 HEAST C adenomas 3.00E-03 IRIS 100 HiRh
Hepatocellular Hepatocellu lar
carcinomas, alterations
2,4- mammary, and USEPA,
Dinitrotoluene 0.680 IRIS 82 renal 2.00 E-03 1992 100 ---
Sources: IRIS (Integrated Risk Information System) (USEPA, 1991c)
HEAST (Health Effects Assessment Summary Tables) (USEPA, 1991 a)
Drinking Water Health Advisory for 2,4- and 2,6-Dlnltrotoluene (USEPA. 1992)
I
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The populations at risk of exposure to these explosives were idennfied by considering
both current and future use scenarios. Currently, public access to the UMDA facility is
restricted, and there is little incentive or opponunity for trespassers to approach the
Washout Plant area, so public exposure is unlikely. There are no operations being
conducted in the Washout Plant area other than remediation, so unplanned exposure of
installation personnel is also unlikely. Therefore, the potential for current exposure was
judged to be low and risks associated with current exposure scenarios were not
evaluated.
The probability of future exposure to human receptors from the Washout Plant and sump
was considered high, however, since it is likely that DoD will eventually vacate UMDA.
A light industtialland use scenario is considered the most probable scenario for future
use of UMDA based on site topography and the availability of utilities and resources. The
exposed population would consist of adult industrial workers. Future residential use is
also possible, although it is not probable, but was not evaluated in the risk assessment
because the industrial scenario is more conservative.
Three exposure pathways for contaminated surfaces were identified for the inuustIidl use
scenario of the Washout Plant building:
Incidental ingestion of contaminated dust
Inhalation of contaminated airborne dust
Dermal absorption of explosives from direct contact with surfaces
The probability of significant exposures by other pathways was considered low. Risks
associated with the contaminated soil were assessed in greater detail during the study
(feasibility study) of the Explosives Was' ')ut Lagoons Soils Operable Unit.
.
.
.
The concentrations of explosives on the accessible building surfaces as detennined during
the remedial investigation (Dames & Moore, 1992b) were used for purposes of
calculating risk for potential human exposure. The risk(s) for potential human exposure
to explosives in the sludge (and water) in the washout water sump were not calculated
because the concentrations of explosives were so high in the sludge (fable 2-1) that the
sludge not only poses a human toxicity hazard (more than four orders of magnitude
greater than the remedial action level of 30 ppm required for the Washout Lagoon Soils),
but also presents an explosion hazard. Therefore, the sump and sump contents will
require remediation to remove this safety and potential human health hazard.
Also, there is a potential for reactive quantities of explosives remaining within the process
equipment in the Washout Plant. Although this does not pose a human toxicity health
risk, per se, because it is contained within the interior ()f the equipment, it does pose a
potential safety hazard. Because of this safety hazard, the selected.remuiy will include
cleanout and removal of the process equipment from the Washout Plant.
In the absence of standard EP A methods for estimating human contaminant uptake from
building interior surfaces, a method developed by the New Jersey Department of
Environmental Protection was used. This method considers the exposure pathways
previously listed, and utilizes assumptions used by EP A to develop remediation goals for
PCB contaminated surfaces. The method assumes that an occupant would absorb 50%
of the total contamination existing in the building during the occupant's total exposme,
2-17
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whether as residential or light industrial use. The amount of contamination was
calculated from the area of the interior surfaces and the following three measures of the
reasonable maximum exposure concentration:
- upper 95% confidence limit on the mean of all measured surface concentrations,
- upper 95% confidence limit on the mean of measured surface concentrations
except the maximum.
- the maximum measured concentration
These three measures were used since the maximum detected concentration was much
higher than the other resultS and could inappropriately skew the average. It also occurred
in a high, inaccessible location in the building. An average daily uptake factor was
calculated by dividing this total uptake by the averaging time and the average weight of a
receptor. The averaging time was assumed to be 25 years for noncarcinogens and 70
years for carcinogens. in accordance with the EP A default values for light industrial use.
Light industrial ~se is the most likely future use for the building. Since the only
difference in this procedure for residential use is dividing by a 30 year averaging time for
noncarcinogens instead of 25 years, in this case the light industrial scenario provides a
higher, more conservative average daily intake.
The basic toxicity information and health effectS criteria for the explosives, including
carcinogenic data from EPA databases were previously presented in Table 2-5. All of the .
explosives are potentially toxic. In addition, both TNT and RDX are classified as
potential human carcinogens (Group C), and 2,4-DNT is classified as a probable human
carcinogen (Group B).
Because of the lack oftoxicity data for TNB, EP A derived a reference dose (RID) by
analogy to DNB. This analogy is considered appropriate and acceptable because of their
structural similarity and the fact that TNB is less toxic on an acute basis than DNB. To
account for the derivation by analogy, the RID for TNB incorporates an additional
uncertainty factor of 10. The Anny has initiated TNB-specific toxicity studies designed to
reduce this uncenainty and provide a more definitive estimate of the RID.
Using the Table 2-5 data and the calculated intake factorS for a combination of the three
significant exposure pathways cited above, excess cancer risks and noncancer hazard
indices were calculated by the NIDEP method (1992) using the three different methods of
averaging surface explosive concentrations noted above (fables 2-6, 2-7, and 2-8). The
risks calculated in Tables 2-6, 2-7, and 2-8 are based on accessible surfaces - those
surfaces up to a height of 6 feet above the floor. Surface areas over 6 feet above the floor
are considered to be (normally) inaccessible and to present approximately one-half the
risk of accessible surfaces for the same concentrations of contaminantS.
Based on a carcinogenic risk of 1 x 10-5 and an III of 1, preliminary remediation goals
(pRGs) were calculated as presented in Table 2-9. It should be noted that only one wipe
sample taken during the RI, P5-6, exceeded the PRGs and this was a sample from a very
inaccessible location (top of a beam in the pelletizer building) which exceed~ the
allowable RDX concentration. For this reason, the 95% UCL arithmetic mean witJwut the
2-18
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Table 2-6: Potential Carcinogenic and Noncarcinogenic Risks Due to Exposure
to the Interior Building Surfaces of the Explosives Washout Plant
(Building 489) using Maximum Detec~ed Concentrations In Wipe
Samples
Maximum
Surface
Explosive Carcinogenic Slope Factor Carcinogenic
Concentration Intake 1 (mglkg/day) Risk
Analyte (~/cm2) (mg/kg/day)
135TNB 0.03 * .* *
246 TNT 8.40 2. I 8E-04 3.0E-02 7E-06
HMX 1.84 * * *
RDX 17.60 4.56E-04 1.1E-Ol 5E-05
Toad 6E-OS
Maximum
Surface
Explosive NoncarcInogenic Reference Noncarcln~genlc
Concentration Intake Dose (Hazard Index)
Analyte (~/cm2) (mg/kg/day) (mg/kglday) Risk
135TNB 0.03 3.48E-06 5.0E-05 7E+02
246TNT 8.40 9.07E-04 5.0E-04 2E+OO
HMX 1.84 1.99E-04 .5.0E-02 4E-03
RDX 17.60 1. 90E-03 5.0E-03 6E-Ol
3E+OO
Total
* Not calculated beciuse contaminant is not considered a carcinogen or slope factor is not
available .
Source: Dames & Moore (1994)
2-19
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Table 2-7: Potential Carcinogenic and Noncarcinogenic Risks Due to Exposure
to the Interior Building Surfaces of the Explosives Washout Plant
(Building 489) using 95 Percent UCL of Arithmetic Mean of
Concentrations In Wipe Samples
Average
Surface
Explosive Carcinogenic
Concentration Intake Slope Factor Carcinogenic
Analyte (~/cm2) (mglkg/day) 1/( mg/kg/day) Risk
135TNB 0.026 * * *
246TNT 2.770 7.I7E-05 3.0E-02 2E-06
HMX 0.569 * * *
RDX 5.070 1.3IE-04 1.IE-OI IE-05
Total
2E-05
Average Non-
Surface Non
Explosive Carcinogenic Reference Carcinogenic
Concentration Intr.ke Dose (Hazard
Analyte w.g/cm2) (mglkglday) (mglkglday) Index) Risk
135TNB 0.026 2.84E-06 5.0E-05 6E-02
246TNT 2.770 2.99E-04 5.0E-04 6E-OI
HMX 0.569 6. 15E-05 5.0E-02 1E-03
RDX 5.070 5.48E-04 3.0E-03 2E-O I
Total u:or
* Not calculated because contaminant is not considered a carcinogen or slope factor is
not available.
Source: Dames & Moore (1994)
2-20
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Table 2- 8: Potential Carcinogenic and Noncarcinogenic Risks Due to Exposure
to the Interior Building Surfaces of the Explosives Washout Plant
(Building 489) using 95 Percent UCL of Arithmetic Mean of
Concentrations other than the Maximum In Wipe Samples
Average Carcinogenic Slope Factor
Surface Intake Carcinogenic
Explosive (mglkg/day) 1/( mglkg/day} Risk
Analyte Concentra-
tlon
W-glcm2}
135TNB 0.024 * * *
246TNT 0.977 2.53E-05 3.0E-02 8E-07
HMX 0.111 * * *
RDX 0.195 5.05E-06 1.1E-Ol 6E-07
Total
1 E-06
Average Non-
Surface Non- Carcinogenic
Explosive. Carcinogenic Reference (Hazard
Concentration Intak~ Dose Index)
Analyte (p.gIcm2) (mglkglday) (m't'kglday) Risk
135TNB 0.024 2. 59E-06 5.0E-05 SE-02
246TNT 0.977 1.06E-04 5.0E-04 1£-01
HMX 0.111 1.20E-05 5.0E-02 2E-04
RDX 0.195 2. llE-05 3.0E-03 1£-03
3E-Ol
Total
* Not calculated because contaminant is not considered a carcinogen or slope factor is
not available. .
Source: Dames & Moore (1994)
2.21
,
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Table 2-9: Preliminary Remediation Goals for the Explosives Washout Plant
(Building 489) Interior Building Surfaces
Accessible Surfaces (below 6 feet)
Analyte Carcinogenic PRG Average. NoncarclnogenlcPRG
(1 E-oS Risk Level) Surface (Hazard Index of 1)
(mg/m2) (J19!cm2) Contamination.. (mg/m2) (~cm2)
w.g/cm2)
135TNB * * 0.024 4.63 0.46
246TNT 128 12.8 0.977 46.3 4.63
HMX * * 0.111 4632 463
RDX 35 3.5 .0.195 278 27.8
Inaccessible Surfaces (above 6 feet)
Analyte Carcinogenic PRG Average NoncarclnogenlcPRG
(1 E-OS Risk Level) Surface (Hazard Index of 1)
(mg/m2) (J,Lg/cm2) Contamination.. (mg/m2) ~cm2}
w.gIcm2)
135TNB * * N/A 9.26 0.92
246TNT 256 25.6 N/A 92.6 9.26
HMX * * N/A 9264 926
RDX 70 7 N/A 556 55.6
. Not calcuJated because contaminant is not considered a carcinogen or slope factor is not available.
.. 95% UCL of Arithmetic Mean Excluding Maximum Wipe Sample of Washout Plant Surfaces
N/A = Not Available
Source: Dames & Moore (1994)
2-22
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maximum concentrations is shown in Table 2-9 for comparison with the PRGs since it
better represents the present level of contamination in the washout building of the
Washout Plant.
The NCP states that the acceptable risk range for carcinogens is 1 x 1 Q-4 to 1 x 10-6 [40
CFR 300.430(e)(2)(i)(A)(2)] For systemic toxicants (Le., constituents having a
noncancer health effect), the NCP states the following:
For systemic toxicants, acceptable exposure levels shall represent concentration
levels to which human populations, including sensitive subgroups, may be
exposed without adverse effect during a lifetime or pan of a lifetime,
incorporating an adequate margin of safety. (40 CFR 300.430(e)(2)(i)(A)(l)]
As discussed earlier. acceptable exposure levels are usually evaluated in terms of the HI;
an In of less than or equal to one generally represents an acceptable exposure. However.
the NCP fmther states that remedial action objectives must consider "factors related to
uncertainty." [40 CFR 300A30(e)(2)(i)(A)(4)] There:ore, the calculated HIs must be
considered within the context of the uncertainty factor, a conservatism that is built into the
EPA-derived RID. For example, if the uncenainty factor is several orders of magnitude
greater than the calculated Ill, an III somewhat greater than 1 may be acceptable.
The potential safety risks of the washout water sump and process equipment interiors are
unacceptable based on Army explosive safety regulations. The potential health toxicity
risks associated with the washout water sump also clearly exceed the acceptable
carcinogenic and noncarcinogenic levels because the measured concentrations of
explosives in the sludge in the sump (Le., 40% and 70% TNT by wt.) greatly exceed the
30 ppm TNT cleanup level selected for soil h the Washout Lagoons Soils ROD (U.S.
Army IR Program, 1992). In addition. because of the long-term exposure of the concrete
sump to such high concentrations of explosives in the sludge, it is expected (but not
confinned) that the interior surfaces of the sump will also not meet the PRGs.
Therefore, in the event of likely future land use changes brought about by UMDA's
inclusion in the BRAC program. actual or threatened releases of hazardous substances
from the site (particularly the sump and possibly the process equipment interior). if not
addressed by implementing the response action selected in this ROD. may present an
imminent and substantial endangerment to public health. welfare. or the environment
2.6.2 Environmental Evaluation
The main potential for fmther release of the explosives to the environment would be if the
washout water sump were not remediated. In this case. fmther release of explosives from
this operable unit (Explosives Washout Plant) to the Explosives Washout Lagoons
Operable Unit would occur.
An ecological assessment that included the Washout Lagoons near the Washout Plant was
performed as part of the installation-wide RIlFS. Qualitative ecological observations and
literature information were included in the feasibility study for the Explosives Washout
Lagoons Soils Operable Unit Although the UMDA installation is part of the critical
winter range and habitat for several threatened and endangered avian species, none of
these are now directly affected by the Washout Plant, nor are they likely to be in the
future.
2-23
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Although there are a number of wetlands near UMDA, none of these occur within the
UMDA boundaries. Information available also indicates that UMDA is not located within
100 or 500 year floodplains.
There are tWo known historic buildings at UMDA, the headquarters building and the
firehouse building. There are also tWo potential archeological resources at UMDA that
have been tentatively identified as a portion of the Oregon Trail and a prehistoric site.
However, none of the activities at the Explosives Washout Plant would affect these
locations.
Finally there are no wildness areas, wildness areas, wildlife refuges or scenic rivers
located within the boundaries of UMDA.
2.6.3 Remedial Action Criteria
Neither state nor federal regulations contain chemical-specific soil cleanup standards for
the contaminants of concern. However, both authorities provide a framework for
developing risk-based remedial action criteria. The State of Oregon requires cleanup to
background or, if that is not feasible, the lowest levels that are protective of human health
and the environment where feasible. The Oregon E!'Ivironmental Oeanup Law process is
as follows:
.
In the event of a release of a hazardous substance, the environment shall be restored
to background level (i.e., the concentration naturally occurring prior to nay release
from the facility (OAR 340-122-040(2)(a)] where feasible.
.
When attaining background is not feasible, the acceptable cleanup level for the
environment shall be the lowest concentration level that satisfies both the "proteetion"
and feasibility" requirements in OAR 340-122-090(1). The party responsible for the
contaminated site is responsible for demonstrating the non-feasibility of attaining
background.
The NCP provides guidelines in terms of acceptable carcinogenic and non-carcinogenic
risk. Therefore, the health criteria cited in Table 2-5, such as slope factors and references
doses, become "to-be-considered" (TBC) criteria for protectiveness.
The potential risk-based preliminary remediation goals were previously presented in
Table 2-9. These risk-based PROs should be readily achievable for the Washout Plant
. building surfaces by any of the remediation alternatives listed below that involve the
pretteattnentsteps. -
. Under RCRA (40 CFR 261), wastewater treattnent sludge from the manufacturing and
processing of explosives is considered a listed waste due to explosive reactivity and is
assigned EP A Hazardous Waste Number K044. Red/pink water from TNT operations is
also considered a listed waste due to explosive reactivity and is assigned EP A Hazardous
Waste Number K047. However, EPA's background listing document supporting these
designations explicitly lists wastes derived from the manufacturing, loading, assembling,
and packing of explosives, not removal from munitions. Therefore, neither the
contamination on the building surfaces nor in the process equipment, nor the sludge or'
water in the washout water sump are specific listed wastes. Furthermore, the RCRA
reactivity criteria, for which the K044 and K047 wastes and reactivity are.not applicable
2-24
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or appropriate in regard to the building surfaces, but may be classified as TBC guidance.
At present, there are no chemical-specific federal or state regulations that specify action or
cleanup levels for explosives-contaminated surfaces. It was for the above reasons that
risk-based PRGs were developed for the Washout Plant building surfaces.
The sludge in the sump does exceed 10% total explosives and is considered detonable or
reactive. However, these materials were generated prior to the effective date of RCRA.
The RCRA regulations governing transportation, storage, treatment and disposal of these
materials are relevant and appropriate for the material as it exists in the sump, and
applicable if the material is removed from the sump and actively managed.
The RCRA reactivity criteria would be appropriate to disposal of possible residual
explosives remaining within the process equipment and tWo of the waste materials
generated during remediation. These are:
.
spent solvent from process equipment washout
solvent wet cloths used for solvent wiping of building or equipment surfaces.
.
These tWo wastes would also be considered FOOI-FOO5listed wastes, as spent solvents
or wipes containing spent solvents. The above three items would be treated/disposed of
by burning and incineration to comply with the regulations for disposal of reactive or
spent solvent wastes.
Location-specific ARARs would include the Endangered Species Act to proteCt rare and
endangered species, the Clean Water Act for protection of wetlands, the National Historic
Preservation Act, and the Archaeological Resources Protection Act. Although areas of
the UMDA installation provide critical habitat for threatened or endangered species, no
activities at the Explosives Washout Plant are expected to impact those habitats. No
archaeological or historic resources are known to exist in vicinity of the Washout Plant or
to be affected by the remedial action. The Washout Plant Operable Unit is not located
within or near a wetland or floodplain.
.fi.
" .
,.~ .
»
Action-specific ARARs are usually technology- or activity-based requirements or
limitations on actions taken with respect to hazardous wastes. These requirements are
triggered by the particular remedial activities that are selected to accomplish a remedy.
The only activity expected to trigger a possible ARAR is the hot gas decontamination
process which may require air monitoring. '
DoD explosives decontamination regulations in Technical Bulletin 7()()-4 specify that
explosives-contaminated equipment be thoroughly decontaminated of explosives,
preferably by thennal means, prior to releasing such equipment from Government
control. Whereas reactive of detonable quantities of explosives are known or suspected
to exist in the washout water sump and Washout Plant process equipment, this
requirement would apply to the washout water sump, the process equipment and surfaces
receiving spills of explosive. The thorough decontamination of the equipment is usually
assured by a heat treatment regimen of time at temperature and/or wipe testing with an
indicator reagent (such as Webster's reagent) to verify there are no detectable residual
explosives. Thennal decontamination of highly contaminated equipment (with reactive
quantities of explosives) down to below detection level by indicator wipe testing (1-10
ug/sq em) should also meet RCRA requirements for thermal destruction of explosives,
2-25
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State of Oregon requirements for cleanup to lowest levels protective of human health and
the environment, and the risk-based PRGs.
On-site CERCLA response actions must only comply with the substantive requirements
of regulations and not the administrative requirements [CERCLA ~ 121(e»). Therefore,
in the event that the remedial alternatives for the Explosives Washout Plant are considered
to take place within the confines of the CERCLA unit (Le., on UMDA), the Army will
not be required to obtain permits, but will have to comply with the substantive
requirements of any statutes or regulations determined to be ARARs.
2.7 Description of Alternatives
After screening numerous potential remedial responses in the feasibility study (Anhur D.
Little, 1993), five major remedial alternatives (including no action) were developed for
the Explosives Washout Plant Operable Unit. Variations of two of these alternatives were
also evaluated, resulting in a total of seven remedial alternatives which are described as
follows:
Alternative 1:
Alternative 2:
Alternative 3:
Alternative 4A:
Alternative 4B:
Alternative 5A:
Alternative 5B:
No Action (Required by law to be considered)
Sump Clean-out/Conttolled Access (Institutional Conttol)
Hydroblasting, Inspection, Demolition, and Disposal
Hot Gas Decontamination, Total Demolition, and Disposal
Hot Gas Decontamination, Partial Demolition, and Disposal
Building Demolition, Inspection, and Disposal of Contaminated
Materials .
Building Demolition, Inspection, Incineration of Concrete Rubble, and
Disposal of Materials
All of the remedial alternatives that were developed and compared in the feasibility study
(except Alternative 1) comply with both the NCP requirements and ArmylDoD safety and
hygiene regulations. For the alternatives that involve actually cleaning the building (those
other than Alternatives 1 and 2), the possible detonable quantities of explosives in the
process equipment and the asbestos and pigeon droppings would be cleaned up during a
"pretreattnent step" (discussed below) and would include building demolition and
disposal steps.
The pretteattnent operations would include:
.
Removal of pigeon droppings and asbestOs from the Washout Plant
Removal of the sludge from the washo!Jt water sump and burning the sludge in the
TNT bum trays at UMDA (as done in the past under a state permit)
.
.
Removal of contaminated water from the washout water sump and adding it to the
compost piles being used for treattnent of the Washout Lagoon Soils
Treatment of the washout water sump for residual explosive by flaming (flaming is
routinely used by the Army for decontamination of explosives and flaming is listed
.
2-26
1w.67062-62.DU6.FinaI ROO.&'94
-------
.
as a decontamination method in EPN600f2-85~28 March 1985 "Guide for
Decontaminating Buildings, Structures & Equipment at Superfund Sites"
Rinsing out the process equipment with a solvent (such as alcohol), as a safety
precaution, to reduce the levels of explosives within the equipment to below
detonable quantities
.
Solvent wiping and removal of electtical wiring and controls from the Washout Plant
Solvent-wipe cleaning of the interior galvanized steel buildings walls below 6 f~t.
and wipe testing above 6 feet. in the washout building
.
.
Solvent wipe cleaning of the pelletizer building (corrugated aluminum) interior walls
and roof (in Alternatives 3, SA, and 5B)
A brief description of each of the remedial alternatives follows.
Alternative 1: NO ACTION
. Capital Cost: None
. _.'
,
Operating and Maintenance COst: None
i.
Net Present Value: None
Months to Implement: None
Both CERCLA and Oregon DEQ regula..."ns require that the "No Action" alternative be
evaluated for every site to establish a baseline for comparison. Under this alternative, the
Anny would take no further action at the site to prevent exposure to the explosives in the
Washout Plant or the associated washout water sump. The existing public access
restrictions would continue only as long as the Anny maintains control over UMDA.
Alternative 2: SUMP CLEAN-OUT/CONTROLLED ACCESS
Remedial Action Design and Planning: $90,000
Initial COst: $55,000
Maintenance and Security Cost: $7,800 per year for 30 years
Net Present Value: . $220,000 (total cost In today's dollars for current
and future capital and operating costs for a period of 30 years)
Months to Implement: Remedial Action Design and Planning = 6 months;
COnstruction = 2 months; Maintenance and Security = 360 months
2.27
-------
This alternative is the minimum action necessary to comply with the risk-based and Anny
safety-based cleanup requirements as long as the Anny retains control of the Washout
Plant One of the other alternatives (Alternatives 3 through 5B) would be required in
order to comply with Army safety requirements if the access restrictions cannot be
maintained on the propeny. In Alternative 2, the water and sludge would be removed
from the washout water sump and disposed of. The empty concrete sump would be
flamed out to destroy any residual explosives and the concrete sump landfllled at UMDA.
The soil beneath and around the sump would be analyzed for explosive contaminants and
removed, as necessary, for treatment under the Washout Lagoons Soil operable unit and
the hole created by removal of the sump filled with clean soil.
The building would be locked and maintained for an indefinite period of time, perhaps up
to 30 years, with a review of the site health and environmental safety risks every 5 years.
Permanent access restrictions would prevent the imminent and substantial endangerment
from explosives, but Army regulations would not permit release of the property without
complete deeontaminatioJ'l.
Alternative 3: HYDROBLASTING, INSPECTION, DEMOLITION,
AND DISPOSAL
Remedial Action Design and Planning: $170,000
Capital Cost:
$150,000
Treatment Operating Cost (Including pretreatment):
$570,000
Net Present Value: $890,000
Months to Implement: Remedial Action Design and Planning = 7 months;
Design/Construction = 2 months; Treatment Operations = 2 months
In this cleanup alternative (hydroblasting), a high pressure water stream would be
directed at the surfaces to be decontaminated. The high p-essure water stream (containing
abrasive grit in this application) would be used to remove.(explosive) contamination and
paint from the surfaces of equipment as well as about one-half inch depth of concrete
from all the concrete surfaces of the building. The water from the hydroblasting operation
would be treated and discharged to the ground at UMDA; the combination of wet grit,
paint, concrete dust, and explosive contaminants from hydroblasting would be sent off
site for disposal by incineration, blending with cement, and subsequent landf1lling as a
nonhazardous waste. The equipment from the building would be inspected for residual
explosive and landfilled, as a nonhazardous waste, at UMDA or off site. The building
would be demolished, the metal siding disposed of as scrap metal, and the concrete
rubble landfilled, as a nonhazardous waste, 3,t UMDA.
2-28
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Alternative 4A: HOT GAS DECONTAMINATION, TOTAL
DEMOLITION, AND DISPOSAL
Remedial Action Design and Planning: $150,000
capital Cost: $410,000
Treatment Operating Cost (Including pretreatment):
$660,000
Net Present Value: $1,220,000
Months to Implement: Remedial Action Design and Planning = 8 months;
Design/Construction = 8 months; Treatment Operations = 4 months
In the hot gas decontamination process, hot gas is used to vaporize and release the
(explosive) contamin::~ts from the non-porous surface of equipment and! or from the
surface or subswrface of porous materials, such as concrete. The hot gas from the
building (or equipment enclosure) then passes through an afterburner (toxic fume
combustor) where the contaminants removed from the building (or equipment) are
destroyed. The hot gas supplied to the building (or equipment enclosure) would either be
generated by a separate burner or by recycling hot gas from the afterburner.
The hot gas decontamination process has been demonstrated and shown to be effective in
the removal of TNT from concrete (both surface and internal) to below deteetable levels at
the Comhusker Army Ammunition Plant (AAP) in Nebraska (Anhur D. Little, 1987a)
and in the removal of TNT, ammonium picrate, and smokeless powder from equipment
to below detectable levels at the Hawthorne AAP in Nevada. .
In this alternative, solvent wiping would be used during the pretreannent steps to
decontaminate the galvanized steel siding in the washout building and the hot gas
decontamination process would be used (after the general pretreatment steps) to
decontaminate aluminum siding in the pelletizer building, the process equipment, and
concrete floors and blast wall in both buildings. Following hot gas decontamination, Jhe
process equipment would be removed from the Washout Plant, transferred to another
government facility or cut up, and disposed of as scrap metal. After complete building
demolition, the concrete rubble would be disposed in a nonhazardous waste landfill on
site and the sheet metal and strUcwral steel disposed of as scrap metal.
Alternative 48: HOT GAS DECONTAMINATION, PARTIAL
DEMOLITION, AND DISPOSAL
Remedial Action Design and Planning: $150,000
capital Cost:
$410,000
Treatment Operating Cost (Including pretreatment):
$560,000
2-29
-------
'"
Net Present Value: $1,120,000
Months to Implement: Remedial Action Design and Planning = 8 months;
Design/Construction = 8 months; Treatment Operations = 4 months
This alternative would be identical to Alternative 4A, except that the washout building of
the Washout Plant would not be demolished, but instead would be retained for
future use.
Alternative 5A BUILDING DEMOLITION. INSPECTION. AND
DISPOSAL OF CONT AMINATED MATERIALS
Remedial Action Design and Planning: $240.000
Capital Cost: None
Treatment Operating Cost (Including pretreatment):
$570,000
Net Present Value: $820,000
Months to Implement: Remedial Action Design and Planning = 10 months;
Design/Construction = 1 month; Treatment Operations = 2 months
In this alternative, the Washout Plant would be demolished after the pretreatment
operations, so no remediation (cleanup) of 'he concrete would have taken place before (or
after) the demolition. As part of the pretreatment operations, the interior of the process
equipment would have been flushed (with a solvent such as alcohol) to remove any large
quantity of explosives, but small quantities of explosive might still remain inside the
equipment.
For reasons of safety, the Washout Plant concrete floor would be broken up by blasting
(using blasting mats) rather than by jackhammer after demolition of the building, The
contaminated process equipment and concrete rubble would be disposed of in an off-site
hazardous waste landfill after the process tanks had been cut open to verify they..
contained no reactive quantity of residual explosives. Besides assuring that the residual
explosives are non-reactive, LDRs also require that the residue pass the TCLP test for
2,4-DNT before being landfilled off site.
The structural steel and metal siding and roofing (which were cleaned up during
pretreatment operations) would be disposed of as scrap metal.
Alternative 58: BUILDING DEMOLITION. CONCRETE TREATMENT.
INSPECTION AND DISPOSAL OF MATERIALS
Remedial Action Design and Planning: $180,000
Capital Cost: None
2-30
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Treatment Operating Cost (Including pretreatment):
$1,000,000
Net Present Value:
$1,180,000
Months to Implement: Remedial Action Design and Planning =
10 months; Design/Construction = 2 months; Treatment Operations = 6 to 9
months
Alternative 5B would be the same as Alternative 5A except that the concrete rubble from
the demolition of the buildings would be burned in a rotary kiln incinerator brought on
site at UMDA so the decontaminated concrete rubble could then be landfilled in a
nonhazardous waste landfill on site at UMDA.
2.8 Summary 01 Comparative Analysis of Alternatives
This section summarizes L~e relative perfonnance of pach of the seven alternatives with
respect to the nine ~RCLA evaluation criteria.
2.8.1
Threshold Criteria
Overall protection 01 human health and the environment. The primary objective
of this remedial action is to reduce the potential risk to human health by explosives in the
washout water sump, possible residual explosive within the process equipment, and
explosive contamination of the interior building surfaces.
There is, currently, no risk to the environment and minimal risk to human health due to
the Washout Plant building because of the containment of the explosive contamination
within the building (and process equipment) and limited access to the building. In
contrast, the washout water sump poses both an environmental and human health hazard,
making Alternative 1 unacceptable. All of the remaining alternatives (2, 3, 4A, 4B, 5A
and 5B) would be protective of human health and the environment, both in regard to the
Washout Plant and the associated washout water sump.
'''''
~,
Compliance with ARARs. All of the alternatives (except No Action) are considered to .
comply with the ARARs. Disposal of the sump sludge by drying and burning the sludge
in the bum pans of the ADA would comply with Army safety regulations and RCRA
requirements for deactivation of reactive characteristic wastes prior'to disposal.
Decontamination of the empty sump by flaming prior to disposal would again comply
with Army safety regulations and RCRA LDRs as well as with Oregon's requirement for
cleanup to background (non-detection) where practical.
Oeanup of the interior walls of the Washout Plant by solvent wiping wo~d meet
Oregons requirement for cleanup to background or, at least, to levelsprotectiv~ of human
health (and the environment) and EPA's requirement for reducing human health risks to
acceptable levels in the case of building re\)se. Solvent washing of the process equipment
interior should meet the RCRA requirement by removing and treating reactive
characteristic materials (explosives) from the equipment, but it would not necessarily
meet Army safety requirements or guarantee that no reactive material would remain. Of
all the alternatives, however, only Alternatives 4A and 4B would assure that Army safety
2.31
-------
regulations were met (i.e., no reactive material remained within the equipment) and non-
detectable levels of explosives were achieved in regard to the process equipment.
2.8.2
Primary Balancing Criteria
Long-term effectiveness. Of all the alternatives, the greatest long-tenn effectiveness
is offered by Alternatives 4A and 48. All of the remaining alternatives except Alternative
I (which has no long-tenn effectiveness) have adequate long-tenn effectiveness and
pennanence.
Reductlon In toxIcity, mobility, or volume of contamInants through treatment.
Alternatives 4A and 48 would reduce tOxicity, mobility, and volume of contaminants to
the greatest extent through the hot gas treatment process. Alternatives 3, 5A and 58, .
would somewhat reduce toxicity in regard to the equipment, and Alternatives 3 and 58
would reduce the toxicity of the concrete rubble from the building. Alternatives 3 and 58
would also reduce the volume of contaminated material. All the alternatives (except
Alternative 1) would reduce mobility of the explosive contaminants through treatment of
the sump and its contents. Alternative 1 provides no reduction in toxicity, mobility, or
volume of contaminated materials.
Short-term effectIveness. All the remedial alternatives can be implemented in tWo
years or less. 8ecause the risks during implementation would be very low, there is no
significant difference among these remedial alternatives in tennS of short-tenn
effectiveness. There is, however, slightly less short-term risk associated with
Alternative 2 than with ~e other remedial alternatives because there would be no
remediation activities associated with the building that could possibly result in any
release. .
Implementablllty. All of the alternatives are readily implementable from an
administrative and technical standpoint In tennS of materials and services, however,
Alternatives 4A and 48 would require additional time for construction and demonstration
of the hot gas decontamination system.
Cost. The least costly (but effective) remedial alternative is Sump CleanoutlControlled
Access, with net present value (the value of money tOday spent over a period of time in
the future), using a 5 percent annual interest rate, of approximately $220,000.
Alternatives 3 and 5A would have a net present value (cost) of about $890,00 and
$820,000 respectively, while Alternatives 4A. 48, and 58 would have a net present
. value cost of over $1 million each.
2.8.3 . Modifying Criteria
State acceptance. The State of Oregon concurS with the Army and EPA in the
selection of Alternative 48. In addition, the state is satisfied that the state's remedial
action process was followed in evaluating remedial action alternatives for the Explosives
Washout Plant Operable Unit.
Public acceptance. 8ased on the absence of any significant negative comments from
the public, it is assumed the public supports the selection of Alternative 48.
2-32
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2.9 Selected Remedy
The selected remedy to clean up the Washout Plant and washout water sump is
Alternative 4B, in which the washout water sump would be remediated by cleanout and
disposal of the standing water and sludge followed by remote flaming of the sump. The
Washout Plant process equipment would be decontaminated by the hot gas process
before removal from the Washout Plant building. The Washout Plant buildings would be
remediated by hot gas decontamination of the concrete and aluminum siding and solvent
wiping of any contaminated galvanized metal siding surfaces.
All the pretreatment stg>s, as described in Section 2.7 (including remediation of the
washout water sump), would be carried out prior to hot gas treatment, including a solvent
wash of the interior of the process equipment for reasons of safety. The interior surfaces
of the Washout Plant building will be treated thennally or by solvent wiping until no
detectable explosives remain on the surfaces.
The hot gas process was selected for the Washout Plant operable unit because it offers the
greatest reduction in toxicity, mobility, and volume of explosive contaminants, l')ng-tenn
effectiveness, compliance with ARARs, and protection of human health and the
environment It also utilizes permanent solutions and alternative (innovative) treatment
technologies to the maximum extent possible. Finally, it makes maximum use of
recovery/recycle of materials by allowing reuse of the main building for future operations
and allows the cleaned up process equipment to be recycled as equipment or scrap metal.
The estimated present worth cost of Alternative 4B is about $1,120,000. The
pretreatment steps all involve proven technology. The hot gas decontamination process is
a relatively new innovative technology that offers the greatest degree of equipment
decontamination (to below the PRGs), and a potential for recycle of scrap metal. The
esrimated volume of process equipment to be treated by the hot gas process is about
3,400 cubic feet. The building surface area requiring solvent wiping during pretreatment
is estimated at 5,000 to 6,000 square feet.
The major components of the selected remedy include the following:
.
Pump out wet explosive sludge from the washout water sump and move it to the.
bum trays in the Ammunition Demolition Area (ADA) area to dry and be burned
.
Pump out contaminated water from the washout water sump and add it to the
compost piles being operated under the Explosives Washout Lagoon Soils Operable
Unit
.
Excavate and flame (by remote operation) the empty washout water sump
Test the soil under the sump, remove any contaminated soil for treatment under the
Washout Lagoon Soils Operable Unit
.
.
Landfill the decontaminated concrete sump (after wipe testing) and refill the hole left
by the sump with clean soil.
2-33
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.
Additional Pretreatment Steps
Remove and dispose of asbestos insulation from piping and process equipment
in an approved off-site landfill
Scrape and vacuum pigeon droppings from the floors for disposal in the on-site
landfill.
Remove electrical wiring and controls from Washout Plant (after solvent wiping)
for disposal as scrap materials
Rinse out process equipment with solvent (such as alcohol), as a safety
precaution, and send waste solvent off site to disposal (by incineration)
Solvent wipe any building surfaces (such as the galvanized steel siding and roof
of the washout building) that indicate explosive conwnination by coloration
and/or reagent wipe test and dispose of the solvent wipes in an off-site
hazardous waste incinerator.
Although all of the internal surfaces of the washout building of the Washout Plant that
were wipe sampled met the PROs for this ROD, it is assumed in all the alternatives in this
ROD (excepfAlternat;ves 1 and 2) that the washout building walls will be solvent-wipe
cleaned (and w~~ tested) up to a height of 6 ft. above the floor. The washout building
walls above 6 ft will be spot tested by wipe sampling and, if any explosive is detected,
also solvent-wipe cleaned. The walls in the pelletizer building will not be wipe-cleaned,
but will be wipe tested after hot gas deconwnination.
Following the pretreatment steps, the tlot gas deconwnination system would be set up
with the hot gas temperature enclosure (oven) inside the Washout Plant washout building
and the burners and controls outside the Washout Plant. The process equipment and
piping in the washout building would be disassembled and treated, in a series of runs, in
the hot gas temperature enclosure to ensure no reactive explosives remain and Army
requirements for thermal treatment of explosives conwninated equipment are met The
hot gas from the hot gas treatment system will be passed through an afterburner to ensure
destruction of any of the vaporized contaminants before the gas is discharged to the
atmOsphere. After the hot gas treatment of the process equipment in the washout
building, the concrete floor and blast wall in the washout building would also be treated
by the hot gas process. Finally, the hot gas process would be used to decontaminate the
entire pelletizer building including the aluminum siding and process equipment (which
was left in place). Following hot gas treatment, the process equipment could be
transferred to another government facility, sold, or disposed of as scrap metal.
The conugated galvanized steel siding in the washout building would be decontaminated
by solvent wiping (during pretreatment) rather than by hot gas decontamination because
the hot gas treatment of this siding would result in severe damage to the siding. (The zinc
coating would melt at the hot gas temperatures and there could be zinc vapor emissions.)
Because this selected remedy will not result in hazardous substances remaining on-site
above health-based levels, the five-year review will not apply to this action and the site
will not require any long-tenn management or review due to .the total remova1ldestruction
of contaminants of concern and hazard. .
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2.10
Statutory Determinations
The selected remedy satisfies the requirements under Section 121 of CERCLA to:
.
Protect human health and the environment
Comply with ARARs
Be cost effective
Utilize pennanent solutions and alternative treatment technologies or reso~e
recovery technologies to the maximum extent practicable
Satisfy the preference for treannent as a principal element
.
.
.
.
2.10.1 Protection of Human Health and the Environment
The selected remedy, Alternative 4B, will reduce the safety and health risks to any future
users of the Washout Plant
.
The safety risks of reactive materials (the explosives) from the sump and process
equipment will be eliminated.
The health and environmental risks from the washout water sump and its conte .ts
will be eliminated.
The health risks associated with the Washout Plant interior surfaces will be reduced
to acceptable limits by reducing the residual concentrations to below the PRGs.
Environmental protection is achieved by eliminating the washout water sump as a
potential source of environmental release of con~ants.
No unacceptable short-term risks or cross-media impacts will be caused by implementing
Alternative 4B. During remediation, adequate protection will be provided to the
community and the environment by contrC'Uing dust generated during materials handling
operations and emission monitoring durUlg the hot gas decontamination process. In
addition, workers will be provided with personal protective equipment and air monitoring
during all phases of remediation.
.
.
.
2.10.2 Compliance with ARARs .
The discussion below addresses compliance of the selected remedy with chemical-
specific, location-specific, and action-specific ARARs.
Chemlcal-specfflc ARARs. The major chemical-specific ARARs are to deactivate any
reactive explosives in the washout plant and sump, and the State's requirement to reduce
the explosives concentrations to background or non-detectable levels. The combination
of sludge disposal, surface flaming of the sump, solvent wiping of the washout building
siding and hot gas decontamination of the process equipment and pelletizer building will
achieve these goals. These procedures will also achieve the DoD requirement to treat or
clean explosives-contaminated equipment prior to unrestricted disposal. DoD explosives
decontamination regulations in Technical Bulletin 700-4 specify that explosives-
contaminated equipment be thoroughly decontaminated of explosives, preferably by
thermal.means, prior to releasing such equipment from Government control.
Thermal decontamination of highly contaminated equipment (with reactive quantities of
explosives) by hot gas treatment or surface flaming down to below detection level by
indicator wipe testing (1 to 10 ug/sq em) should also meet RCRA requirements for
2.35
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destruction of explosives, State of Oregon requirements for cleanup to the lowest le.vels
protective of human health and the environment, and the risk-based PROs.
The regulations regarding K044 and K047 wastes and reactivity are not applicable or
appropriate in regard to Washout Plant building surfaces but may be classified as TBC
guidance. At present, there are no chemical-specific federal or state regulations that
. specify action or cleanup levels for explosive-contaminated surfaces. It was for the above
reasons that risk-based PROs were developed for the Washout Plant building surfaces.
The selected (multistep) remedy should actually exceed these PROs sufficiently to meet
DoD and Oregon StatP. requirements of decontamination to non-detectable levels.
The RCRA reactivity and/or ignitability criteria would however, be either applicable or
relevant and appropriate, however, to disposal of four of the waste materials that might
be generated dming remediation. These are:
.
possible residual explosives remaining within process equipment
.
the sludge in t1&.; washout water sump
spent solvent from process equipment washout
.
.
solvent wet cloths used for solvent wiping of the building or equipment surfaces
The above four items would be disposed of by burning or incineration to comply with the
land disposal regulations for disposal of characteristic reactive or ignitable, or listed spent
solvent wastes.
The sludge from the washout water sump and any solid explosive residue removed from
the interior of the process equipment would be disposed of by burning in the burn trays
of the ADA. The waste solvent and solvent wet rags would be sent to an off-site
hazardous waste incinerator for disposal.
Since the selected remedy is expected to achieve cleanup to non-detectable (i.e..
background) levels of explosives in the sump, washout plant buildings and process
equipment, it should thereby meet DEQs requiremeni for. cleanup to background levels.
LocsUon-specNlc ARARs. No location-specific ARARs are triggered for this
alternative. Although areas of the UMDA installation provide critical habitat for
threatened or endangered species, no activities at the Explosives Washout Plant are
expected to impact those habitats. No archaeological or historic resources are known to
exist in vicinity of the washout plant or to be affected by the remedial action. The
washout plant operable unit is not located within or near a wetland or floodplain.
Action-specific ARARs. Action-specific ARARs are usually technology- or activity-
based requirements or limitations on actions taken with respect to hazardous wastes.
Testing or monitoring of the off-gas from the hot gas system afterburner will be required
by the state or EP A. Open burning in the ADA burn trays such as used for deactivation of
the sump sludge would normally be a state permined operation. Currently, a state air
contaminant discharge permit allows open burning and open detonation of explosive
materials in the ADA. Although the permit may not still be in force at the time of the
2-36
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Washout Plant remediation, the conditions of the pennit would still be met during
remediation. These open burning/open detonation activities are listed in UMDA's RCRA
pan B pennit application and are currently being carried out under interim status.
OSHA safety requirements will have to be observed during removal of the asbestos from
the Washout Plant equipment and piping by a licensed contraCtor as well as during the
handling of solvents used for rinsing out the process equipment and performing the
solvent wiping of surfaces. All the hazardous waste operations requirements of 29 CFR
1910.120 will also have to be met during site remediation. .
The asbestos waste, waste solvent and solvent wet rags must be handled on-site in
compliance with RCRA regulations and disposed of off-site in RCRA permined facilities.
Finally, Anny safety approval will be required for the plans for decontaminating the
washout water sump by remote flaming arid Anny safety requirements will have to be
met during disassembly of the equipment and piping and during its decontamination by
the hot gas pror"ss.
2.10.3 Cost-Effectiveness
Although it is more costly than several of the other alternatives, the Hot Gas
Decontamination Alternative is the only alternative that assures compliance with
Department of the Anny explosives decontamination regulations and ARARs while also
preserving the value of the washout building for future use under the BRAC Program. It
also provides the greatest overall proteCtion of human health and the environment,
compliance with ARARs, long-term effectiveness, and the reduction of toxicity, mobility,
and volume of all the alternatives. .
2.10.4 Utilization of Permanent Solutions and Alternative Treatment
Technologies or Resource Recovery Technologies to the Maximum
Extent Practicable
The selected remedy of hot gastreannent of the pelletizer building, process equipment
and concrete portion of the washout building of the Washout Plant meets the statutory
requirements to utilize permanent solutions (because of complete destrUction of the
explosive contaminants) and alternative (innovative; more efficient) treatment
teChnologies to the maximum extent practical. An analogous treatment technology,
flaming, will provide for permanent decontamination of the washout water sump.
This remedy also provides for the maximum use and recycle of materials through reuse of
the washout building of the Washout Plant for other activities and reclaim of process
equipment for reuse or recycle as scrap metal.
The suppon of the state and community in the evaluation process and the selection of
Alternative 4B, Hot Gas Decontamination, further justify the selection of this alternative. .
2.10.5 Preference for Treatment as a ~rlnclpal Element
The statutory preference for treannent is satisfied by using the hot gas decontamination
process as the primary means for addressing and destroying the explosives contaminants
in the Washout Plant building and flaming for the decontamination of the washout water
sump. .
2-37
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2.11
Documentation of Significant Changes
The selected remedy was the preferred alternative presented in the Proposed Plan. No
changes have been made.
2-38
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3.0 Responsiveness Summary
The final component of the ROD is the Responsiveness S umrnary, which serves two
purposes. First, it provides the agency decision makers with infonnation about
community preferences regarding the remedial alternatives and general concerns about the
site. Second, it demonstrates to members of the public how their comments were taken
into account as pan of the decision-making process.
Historically, community interest in the UMDA installation has centered on the impacts of
installation operations on the local economy. Interest in the environmental impacts of
UMDA activities has typically been low. Only the proposed chemical demilitarization
program, which is separate from CERCLA remediation programs, has drawn substantial
comment and concern.
As pan of the installation's community relations program, UMDA assembled in 1988 a
Technical Review Connninee (lRC) composed of elected and appointed officials and
interested citizens from the surrounding communities. Quanerly meetings provide an
opportunity for UMDA to brief the TRC on installation environmental restoration projects
and to solicit input from t.~e TRC. Approximately 20 TRC meetings have been held since
the TRC was creatw. A TRC meeting was held on January 27, 1993, during preparation
of the feasibility study for the Explosives Vl ashout Plant Operable Unit. In that meeting,
the TRC was briefed on the scope and methodology of the remedial alternatives
considered in the feasibility study. In December 1993, the TRC was changed to a
Restoration Advisory Board (RAB) with similar functions. Two RAB meetings have
been held since then.
The feasibility study and proposed plan for the Explosives Washout Plant Operable Unit
were made available to the public on February 15, 1994, at the following information
repositories: UMDA Building 32, Hermistol1, Oregon; the Hermiston Public Library,
Henniston, Oregon; and the EP A office in Portland, Oregon. The documents constituting
the administrative record for this site were made available at the office of the BRAC
Environmental Coordinator, Umatilla Depot Activity, Building 32, Hermiston, Oregon
97838.
Notice of the public comment period, public meeting, and availability of the proposed
plan for the Washout Plant was published in the l~gal announcement section of
Hermiston Herald, the Tri-City Herald, and the East Oregonian on February 15, 1994.
A public meeting was held at the Armand Larive Junior High School, Hermiston,
Oregon, on March 2, 1994, to inform the public of the preferred alternative and to seek
public comments. At this meeting, representatives from UMDA, USAEC, EPA, ODEQ,
and Arthur D. Little presented the proposed remedy and were available to answer
questions regarding the preferred alternative. Six persons from the public and media
attended the meeting. Questions asked during the infonnal question and answer period
requested more detail regarding enclosing the Washout Plant during remediation (not
required) and the effect of the hot gas decontaminatiOI1 process on the structural integrity
of the buildings (only a minor effect). The public comment period ended on March 17,
1994.. .
Two written comments were received during the public comment period following the
March 2, 1994, public meeting. These comments and the Army responses have been
included as attachments to this Responsiveness Summary.
3-1
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Comment No.1
I am very concerned about the Anny's plan to incinerate weapons at the Umatilla Anny
Depot. Incineration is not safe. What we burn is not filtered out 100% and more and
more is being discovered every year about the health risks involved in incineration.
Army Response
Thank you for your interest in the cleanup plans for Umatilla Depot Activity. The
cleanup plans that are currently under consideration and were discussed at the March 2,
1994, Public Meeting were directed to the cleanup of contaminated soil, ground watt'"
and buildings and do not involve chemical or conventional weapons. In addition,
incineration usually refers to burning solid or liquid materials, neither of which is
. proposed for UMDA for any of the re~tion (cleanup) sites that were discussed
during the March 2, 1994, presentation at the Annand Larive Junior High School. .
Mterburners and/or scrubrers are often used following an incinerator as an air pollution
(or safety) control devices to make sure no unburnt materials, dust, or acid gases from
the incinerator escape to the environment.
In the hot gas process proposed for the Washout Plant at UMDA, hot air (or combustion
gases) would be passed through an insulated section of the building or insulated
enclosure containing explosive contaminated equipment to break down and vaporize the
residual explosives (any explosives left behind after othe~ cleanup methods, such as
solvent washing, were used). The hot gases would then be passed through an
afterburner at 1,800.P to make sure any explosive breakdown products are thoroughly
destroyed. This hot gas process has been tested at two Anny ammunition plants. Test
results showed no acid gas or dust emission that would require a scrubber. The only
fully accepted method for destroying explosives in contaminated equipment where
residual explosives may be caught in cracks or crevices, and where the explosives cannot
be safely removed by any other means, thus posing potential for explosion is by heating.
At many existing explosive production plants, explosive contaminated equipment is
heated in ovens, to destroy residual explosives, without air pollution control systems
such as afterburners. However, it is likely that in the future, air pollution controls (such
as afterburners) will be required by the EPA.
3-2
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Comment No.2
We agree that it is necessary to cleanup specific areas at the UMDA due to contamination
problems. We can not suppon any project that uses incineration as a disposal method or
cleanup method. Incineration changes one fonn of contamination into another by
releasing emissions through the smokestack.
Why was there no public notice about membership on this commission? An
announcement at the March 2, 1994, Public Meeting is not an acceptable method of
notifying the public about commission membership applications.
Army Response
Thank you for your interest in the cleanup plans for Umatilla Depot' Activity.
Incineration usually refers to burning solid or liquid materials, neither of which is
proposed for UMDA for any of the remediation (cleanup) sites that were discussed
during the March 2, 1994, presentation at the Armand Larive Junior High Scl'oool.
Afterburners and/or scrubbers are often used following an incinerator as an air pollution
(or safety) control devices to make sure no unburnt materials, dust, or acid gases from
the incinerator escape to the environment.
In the hot gas process proposed for the Washout Plant at UMDA, hot air (or combustion
gases) would be passed through an insulated section of the building or insulated
enclosure containing explosive contaminated equipment to break down and vaporize the
residual explosives (any explosives left behind after other cleanup methods, such as
solvent washing, were used). The hot gases would then be passed through an '
afterburner at 1,800.F to make sure any explosive breakdown products are thoroughly
destroyed. This hot gas process has been tested at two Anny ammunition plants. Test
results showed no acid gas or dust emission that would require a scrubber. The only
fully accepted method for destroying explosives in contaminated equipment where
residual explosives may be caught in cracks or crevices, and where the explosives cannot
be safely removed by any other means,thus posing potential for explosion is by heating.
At many existing explosive production plants, explosive contaminated equipment is
heated in ovens, to destroy residual explosives, without air pollution control systems .
such as afterburners. However, it is likely that in the future, air pollution controls (such
as afterburners) will be required by the EPA.
Gt,lidance on forming Restoration Advisory Boards (RABs) is still being developed
within the Anny. Current draft guidance provides options for soliciting membership.
One such option, issuing a news release, was used at the Umatilla Depot A news release
was issued on December 9, 1993 to the Hermiston Herald, East Oregonian, and Tn-City
Herald, and various local radio and TV stations. The release indicated that the Umatilla
Depot was forming a RAB from the existing Technical Review Committee (TRC), and
that interested persons wishing to join the RAB should attend the TRC meeting on
December 15, 1993. Only the East Oregonian printed the meeting notice, and did not
note the open membership to the RAB.
3-3
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In order to ensure that an invitation to the RAB is published. a paid advertisement will be
placed in the Hermiston Herald, East Oregonian, and Tri-City Herald in April 1994.
Anyone who responds will be given a fact sheet and RAB membership application.
Membership applications will be accepted through May 31, 1994.
3-4
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.
Ap.pendlx A
Oregon DEQ Letter of Concurrence
".670Ei;U2.0U6.FnaI AOO.&'94
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July 26, 1994
DEPART~'IENT 0
r:'-.iVIRONYrE!\'T,-\
QUAlITY
Mr. Chuck Clarke
Regional Administrator, Region 10
U. S. Environmental Protection Agency
, 200 Sixth A venue
Seattle, WA 98101
Re:
Umatilla Depot Activity
explosiVes Washout Plant
Operable Unit
Record of Decision
Dear Mr. Clarke;
The Oregon Department of Environmental Quality (DEQ) has reviewed the final Record of
Decision. for the Explosives Washout Plant Operable Unit at the U.S. Army's Umatilla Depot
Activity (UMCA). I am pleased to advise you that DEQ concurs with the remedy
recommended by EPA and the Army- The major components of thet remedy include:
.
Removal, treatment and disposal of explosives-contaminated waStewater and sludge
from the concrete sump: .
.
Decontamination by flaming, demolition a"d landfill disposal of the concrete sump;
.
Pretreatment of the Washout Plant process equipment (removal of asbestos, cleanup
of pigeon droppings, and solvent flush): .
.
Treatment by solvent wiping of gajvanized steel siding, and by hot gas decontamination
of the aluminum siding, concrete and process equipment;
.
Removal and recycling/disposal of the process equipment; and,
.
Demolition of the pelletizer building.
I find that this remedy is protective, snd to the maximum eXtent practicabJe is .cost effective.
uses permanent solUtions and alternative technologies, is effective and implemenuble.
Accordingly, it satisfies the requirementS of ORS 465.315, and OAR 340-122.'()40and 090.
8!
~'. .:
...
811 SW Sixth Avenue
Portl.utd, OR 972()4.13':I(1
(503) 229.5696
TOD (50.3) 229-6993 r.-
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Chuck Clarke
Page 2
It is understood that placement of any demolition wastes from this operable unit into the
Depot's Active landfill is subject to the requirements of the permit for the landfill, previously
issued by this Department.
If you have any questions concerning this maner, please contact Bill Dana of DEa's Waste
Management and Cleanup Division at (503) 229-6530.
Sincerely.
~~~
Fred Hansen
Director
BD:m
SITE\SM5939.
cc: Lewis.D. Walker. DOD
lTC. Moses Whitehurst, Jr.,
Harrv Craig, EPA-oOO
Jeff Rodin. EPA, Seattle
Bill Dana, DEQlWMCD
. Stepl1anie Hallock, DEOIERO
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Appendix B
References
-------
The following references are included with this ROD as a convenience to the reader and
only constitute a partial list of the documents used in the preparation of the ROD. A
complete listing of the documents used in the preparation of this ROD and other official
repons and records pertaining to this operable unit are contained in the administrative
record for this operable unit. The administrative record is available for review at the
office of the BRAC Environmental Coordinator, Umatilla Depot Activity, Building 32,
Hermiston Oregon, Monday through Thursday, 8 AM - 4 PM (503) 564-5294.
1. Arthur D. Little, Inc. 1993. Final Feasibility Srudy for the Explosives WashoUt Plant
- Building 489 (OU-6) at the Umatilla Depot Activity (UMDA). Prepared for U.S.
Army Environmental Center, ContraCt DAAAI5-91-D-OOI6, Delivery Order No.2.
December.
2. Anhur D. Little 1987a. Pilot Plant Testing of Caustic Spray/Hot Gas Building
Decontamination Process. Prepared for U.S. Army Toxic and Hazardous Materials
Agency, ContraCt No. DAAKI1-85-D-0008, Task Order No.5. August 1987.
3. Anhur D. Little, Inc. 1987b. Testing to Determine Relationship Between Explosive
Contaminated Sludge Components and Reacrivity. Prepared for the U.S. Army
Toxic and Hazardous Materials Agency. Repon No. AMXTH- TE-CR-86096,
January 1987.
4. CH2M Hill and Morrison Knudsen Environmental Services. 1992. Feasibility Study
for the Explosives WashoUt Lagoons (Site 4) Soils Operable Unit, Umatilla Depot.
Activity, Hermiston OR. Prepared for the U.S. Army Toxic and Hazardous
Materials Agency, ContraCt DE-Aa>6-76RL 01830. April 1992.
5. Dames & Moore. 1990. Final Enhanced Preliminary Assessment for Umatilla Depot
Activity. Volumes 1 and 2. Prepared for the U.S. Army Toxic and Hazardous
Materials Agency, Contract No. DAAAI5-88-D-0008, Delivery Order No.3.
April 1990. .
6. Dames & Moore. 1992a. Final Human Health Baseline Risk Assessmentfor the
Umatilla Depot Activity Hermiston, Oregon. Prepared for U.S. Army Toxic and
. Hazardous Materials Agency, ContraCt No. DAAAI5-88-D-0008, Delivery Order
No.3. August 1992.
. 7. Dames & Moore. 1992b. Final Remedial Investigation ReporrfoT: the UmatilLa Depot
Activity Hermiston, Oregon. Volumes J through 6. Prepared for the U.S. Army
Toxic and Hazardous Materials Agency, Contract No. DAAAI5-88-D-0008,
Delivery Order No.3. August 1992. .
8. Dames & Moore. 1994. Addendum to the Hwnan Health Baseline Risk Assessment
Explosives WashoUt Plant Umatilla Depot Activity, Hermiston OR. Prepared for
U.S. Army Environmental Center, Aberdeen Proving Ground, MD, Contract No.
DAAA 15-88-D-0008, Delivery Order 3. February 1994.
9. New Jersey Department of Environmental ProteCtion. 1992. Technical Basis and .
Backgroundfor Cleanup Standards for Contaminated Sites, NJAC 7:26D.
B-'
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10. Oak Ridge National Laboratory (ORNL). 1991. Assessment of Applicable or
Relevant and Appropriate Requirements (ARARs)for Umatilla Depot Activity,
Explosive Washout Lagoons, Oregon. Prepared by the Health and Safety Research
Division of ORNL for the U.S. Anny Toxic and Hazardous Materials Agency. May
1991.
11. U.S. Army Installation Restoration Program, 1992. Record of Decision Umatilla
Depot Activity Explosives Washout Lagoons Soils Operable Unit (Sept. 1992)
12. U.S. Environmental Protection Agency. 1992. Drinking Water Health Advisory for
. 2,4-and 2,6-Dinitrotoluene, Health and Ecological Criteria Division, Office of
Science and Technology, Office of Water, Washington, D.C., April 1992.
13. U.S. Environmental Protection Agency. 1991a. Health Effects Assessment
Summary Tables, First Quaner FY 1991, OERR 9200.6-303-(91-1),
Washington, D.C.
14. U.S. Environmental Protection Agency 1991 c. Integrated Risk I nformatL . t System,
Online, Office 0/ Health and Environmental Assessment, Environmental Criteria and
Assessment Office, Cincinnati, Ohio. September, 1991.
15. U.S. Environmental Protection Agency 1989. Interagency Agreement BetWeen the
U.5. Environmental Protection Agency, Region X, the Oregon Department 0/
Environmental Quality, the U. S. Army, and the U.5. Army Depot Activity
Umatilla. October 31,1989.
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