United States
Environmental P~.Jction
Agency
Office of
Emergency and
Remedial Response
EPNROD/R08-92/061
September 1992
PB93-964409
&EPA
Superfund
Record of Decision:
Ogden Defense Depot (Oper-
able Unit 4), UT
EPA Report Collection
Information Resource Center
US EPA Region 3
Philadelphia, PA 19107
u . 5. Envlronmemal ~rotectlon Agency
Region III Hazardous Waste
Technical Information Center
84 1 Chestnut Street ,9th Floor
Philadelphia, PA 19107
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NOTICE
The appendices listed in the index that are not found in this document have been removed at the request of
the issuing agency. They contain material which su~ but adds no further applicable information to
the content of the document. All supplemental material is. however. con1ained in the administrative record
for this site.
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50272.101
REPORT DOCUMENTATION 11. REPORTNO. I ~ 3. Recipient'. Acceaeion No.
PAGE EPA/ROD/R08-92/061
4. TItle and Subtitle 5. Report Date
SUPERFUND RECORD OF DECISION 09/28/92
Ogden Defense Depot (Operable Unit 4), UT
6.
Third Remedial Action - Subsequent to follow
7. Author(.) 8. Perfonning Organization RepL No.
8. Perfonnlng Orgalnlzatlon Name and Add..... 10. ProjectlTaaklWork Unit No.
11. Contract(C) or Gr.nt(G) No.
(C)
(G)
1~ Sponaorlng Organization Name and Addre.. 13. Type of Report & Period Covered
U.S. Environmental Protection Agency 800/000
401 M Street, S.W.
Washington, D.C. 20460 14.
15. Supplemantary Notel
PB93-964409
16. Abetract (Umit: 200 worda)
The 1,100-acre Ogden Defense Depot site has been a key installation in the Department
of Defense (DOD) supply system in Ogden, Weber County, Utah. Land use in the area is
predominantly residential. In the past, both liquid and solid materials have been
buried, burned, or disposed of in several areas at the Defense Distribution Depot,
Ogden, Utah (DDOU). These areas have been divided into four operable units. OU4 is
composed of Burial Sites 4-A through 4-E. From the 1950's to 1975, a records search of
Burial Site 4-A indicated that approximately 14,000 pounds of waste material were
disposed of in this area each month. In addition, approximately 40 gallons of waste
oils per day were collected in drums and disposed of onsite in 4A. Burial Sites 4-B
and 4-E operated as a waste oil/holding/burning pit. From 1969 to 1972, Burial Site
4-C was operated as a sanitary landfill. From the mid-1940's to mid-1960's, methyl
bromide cylinders were reportedly disposed of in Burial Site 4-D; however, during site
investigations, only large quantities of halazone water purification tablets contained
in bottles were encountered. From the mid-1950's to mid-1960's, Burial Site 4-E was
used as an oil holding/burning pit for waste oils and spent solvents, and industrial
wastes produced from various processes on the Depot. This ROD addresses the five
(See Attached Page)
17. Document Analy.l. .. Deaerlplora
Record of Decision - ogden Defense Depot (Operable Unit 4), UT
Third Remedial Action - Subsequent to follow
Contaminated Media: soil, debris, gw
Key Contaminants: VOCs (benzene), other organics (PCBs, pesticides), metals (arsenic,
b. IdentifieralOpen-Ended Terme chromi urn, lead)
c. COSAl1 Reid/Group
1S. Availability Statement 19. Security Cia.. (This Report) 21. No. of Pagea
None 72
20. Security Cia.. (Thia Page) ~ Price
None
272(4-77)
(See ANSI.z38.1S)
See Instructions on Re verse
(Formerty N11~)
Department of Commerce
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EPA/ROD/R08-92/061
Ogden Defense Depot (Operable Unit 4), UT
Third Remedial Action - Subsequent to follow
Abstract (Continued)
burial sites as OU4. DDOU's analysis indicated that the soil in Burial Site 4-E is the
primary source of ground water contamination, whereas Burial Site 4-A is considered a
potential secondary source. OU4 is the third final response action and its goal is to
reduce the principal threat posed by contaminated soil and shallow ground water that may
occur as a result of future exposure of residents or onsite workers. The ROD for OU1 is
under review, OU2 is being implemented, and the ROD for OU3 is being prepared. The
primary contaminants of concern affecting the soil, debris, and ground water are VOCs,
including benzene; other organics, including pesticides and PCBs; and metals, including
arsenic, chromium, and lead.
The selected remedial action for this site includes excavating and transporting offsite
approximately 4,500 cubic yards of contaminated soil, debris, and approximately 400 cubic
yards of water purification tablets for disposal at a RCRA landfill; conducting TCLP
tests to confirm the characteristics of excavated soil and debris and to determine their
suitability for land disposal; treating any soil and debris failing TCLP offsite using
activated carbon, other stabilization/fixation methods, or, for dioxins, incineration;
excavating and removing any contaminated cylinders for offsite treatment and disposal;
backfilling excavated areas with clean fill and soil, with revegetation; extracting and
treating onsite 65 million gallons of contaminated ground water using air stripping to
remove VOCs and carbon adsorption to remove organics followed by reinjection into the
shallow aquifer; monitoring ground water and air emissions; and removing wastes generated
during the treatment process offsite for disposal or incineration. The present worth
cost for this remedial action ranges from $3,800,000 to $4,500,000, which includes an
estimated annual O&M cost of $230,000 for 12 years.
PERFORMANCE STANDARDS OR GOALS:
Chemical-specific soil clean-up goals are based on the TBC remediation criterion for PCBs
of 25 mg/kg (EPA Directive 9355.4-01FS) and the TBC criterion for dioxins of 0.001 mg/l
(General Approach Used by the Dioxin Disposal Advisory Group Regarding Pentachlorophenol
Waste). All remaining goals are based on a future residential exposure scenario and
include benzene 210 mg/kg (cancer risks of 10-5); arsenic 35 mg/kg (cancer risk of 10-4);
and lead 500 mg/kg. Chemical-specific ground water clean-up goals are based on federal
MCLs for benzene 0.005 mg/l; cis-l,2-DCE 0.07 mg/l; vinyl chloride 0.002 mg/l; and PCBs
0.005 mg/l.
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-Cl~:j!
Defense Distribution Depot
Ogden, Utah
--- -- ___0_____0 .-.n.. -
Final
Record ot Decision and
Responsi.veness Summary
tor Operable Unit 4
August 3, 1992
JIM James M Montgomery
.
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FINAL RECORD OF DECISION
AND
RESPONSIVENESS SUMMARY
FOR OPERABLE UNrr 4
DEFENSE DlSl'RIBurIONDEPOT OGDEN, UTAH
This is a primary document of the DDOU RIlFS. It will be available in the Administrative
Record, which is maintained at the:
Weber County Library
2464 Jefferson"Avenue
Ogden, Utah
Hours:
10 am - 9 pm (Monday-Thursday)
10 am - 6 pm (Friday and Saturday)
FFASubmittal Date: August 3, 1992
Actual SubmiU:al Date: August 3, 1992
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Defense Distribution Depot
Ogden, Utah
Operable Unit 4
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Declaration for tile
Record of Decision
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DDOU OPERABLE UNIT 4
DECLARATION
FOR THE
RECORD OF DECISION .
Site Name and Location
Defense Distribution Depot Ogden, Utah
Ogden, Weber County, Utah
Operable Unit 4 - Burial Sites 4-A through 4-E
St.satPYnPnt of Basis and Purpose
This decision document presents the remedial action for Defense Distribution Depot
Ogden, Utah (DDOU) Operabl~ Unit 4 (OU 4), selected 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). This decision is based on the Administrative Record
for DDOU OU 4.
The State of Utah Department of Environmental Quality (UDEQ) and the US
Environmental Protection Agency (EPA) concur on the selected remedy presented in this
Record of Decision (ROD).
As&~ ~ oftbe Site
Actual or threatened releases of hazardous substances from this site, 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.
Dt:-aiption oftbe SeJected ~
Operable Unit 4 consists of five burial areas in the northern portion of DDOU. The remedy
for OU 4 addresses the principal threats posed by contaminated soil in these burial areas,
and ground-water contamination underlying these areas. The remedy will remove these
principal threats by excavating and disposing of the contaminated soil and removing the
ground-water contaminants through treatment. The water purification tablet bottles
encountered in Burial Site 4-D, while not a source of ground-water OT soil contamination,
could be a health risk to future residents. This area will also be excavated to remove this
potential threat.
The selected remedy for DDOU OU 4 will remove these principal threats by the following
actions: .
.
. Excavate and transport approximately 4,500 cubic yards of contaminated soil
. and debris off site for disposal in a RCRA permitted hazardous waste landfill.
.
Excavate and transport approximately 400 cubic yards of water purification
tablets off site for disposal in a RCRA permitted industrial landfill.
.
Extract contaminated ground water, treat by air stripping and carbon
adsorption, and reinject into the shallow aquifer.
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Ground-water monitoring will be conducted to ensure the effectiveness of the ground-water
treatment alternative. "
This alternative will
contaminated shallow
management. "
control potential future exposures and risks associated with
ground water such that the site will not require any long-term
Statutory Determinations
The selected remedy is protective of human health and the environment, complies with
Federal and State requirements that are legally applicable or relevant and appropriate to
the remedial action, and is cost-effective. Because treatment of soils was not found to be
practicable, the disposal of soils off site does not satisfy the statutory preference for
treatment as a principal element. This remedy utilizes permanent solutions and
treatment technologies to the maximum extent practicable for ground-water remediation
and satisfies the statutory preference for remedies that employ.treatment that reduces
toxicity, mobility, or volume as a principal element. In order to ensure that ground-water
treatm"ent continues to provide adequate protection of human health and the environment, a
review will be conducted by DDOU within five years after commencement of the remedial
action.
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UNITED STATES ENVIRONMENTAL
PROTECTION AGENCY
l
IU-V/K f~
// Jack W. McGraw
ACt}NG REGIONAL ADMINISTRATOR
By:
-3-
Date:
«irZŁ<- .
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STATE OF UTAH
DEPARTMENT ot ENVIRONMENTAL QUALITY
. .-:: / I/~':"'" " /
. /...Ji ~
'. ,,,., 1...--' . .
. , II I" ,
By: ' y', /./ !i.;/ /i /1" ~.:;: ~ Date:
I Kenneth t. Aikema ....'
EXECUTIVE DIRECTOR.
UTAH DEPARTMENT OF
ENVIRONMENTAL QUALITY
( - ') .-...
) L (, (
,,"I -,
::-'CI 17'-1~
-4.
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DEFENSE DISTRIBUTION DEPOT OGDEN, UTAH
By:
\ - ... ".
Date:
M. D. Curry, CAPI'., USN
COMMANDING OFFICER
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,
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Defense Distribution Depot
Ogden, Utah
Operable Unit 4
Decision Summary lor tlte
Record 01 Decision
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TABLE OF CONTENTS
1.0 SITE NAME, LOCATION, AND DESCRIPI'ION
2.0 SITE HISTORY AND ENFORCEMENT ACTIVITIES
2.1 History
2.2 Scope and Role of Operable Unit 4
2.3 Enforcement History
2.4 Investigation History ,
2.5 Community Relations History
3.0 SITE CHARACTERIZATION
3.1 Nature and Extent of Contamination
3.1.1 Nature and Extent of Soil Contamination
3.1.2 Nature and Extent of Ground-Water Contamination
3.2 Public Health and Environmental Impacts
3.2.1 Contaminant Identification
3.2.2 Exposure Assessment
3.2.3 Toxicity Assessment
3.2.4 Risk Characterization
3.2.5 Uncertainties
3.2.6 Summary of Site Risks
4.0 ALTERNATIVE.S EVALUATION
.4.1 Development of Preliminary Alternatives
4.2 Initial SCTeening of Preliminary Alternatives
4.3 Description of Alternatives
4.3.1 Alternative 1 - No Action
4.3.2 Alternative 2 - Containment of Contaminated Soil and
Ground-Water Treatment by Air Stripping and GAC
4.3.3 Alternative 3a - Off-Site Soil Disposal and Ground-Water
Treatment by Air Stripping and GAC
4.3.4 Alternative 3b - Off-Site Incineration and Ground-Water
. Treatment by Air Stripping and GAC
4.3.5 Alternative 4a - On-Site Soil Treatment by Dechlorination
and Ground-Water Treatment by Air Stripping and GAC
.4.3.6 Alternative 4b - On-Site Soil Treatment by Incineration and
Ground-Water Treatment by Air Stripping and GAC
4.3.7 Alternative 5 - Containment of Contaminated Soil and
Ground-Water Treatment by UV/Ozone
4.3.8 Alternative 6a - Off-Site Soil Disposal and Ground-Water
Treatment by UV/Ozone
4.3.9 Alternative 6b - Off-Site Soil Incineration and Ground-Water
Treatment by UV/Ozone . .
4.3.10 Alternative 7a - On-Site Soil Treatment by Dechlorination
and Ground-Water TTeatment by UV/Ozone
4.3.11 Alternative 7b - On-Site Soil Treatment by Incineration
. and Growid-Water Treatment by UV/Ozone
4.4 Comparative Analysis of Remediation Alternatives
i
PAGE
1
2
2
3
3
3
4
5
5
5
6
7
8
8
8
9
10
10
10
10
12
15
15
15
18
19
19
a>
a>
21
21
21
22
22
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Table of Contents
5.0 SELECTED REMEDY
25
5.1 Description of the Selected Remedy
5.1.1 Remediation Goals
5.1.2 Costs
5.2 Statutory Determinations
5.2.1 Protection of Human Health and the Environment
5.2.2 Compliance with Applicable OT Relevant ~nd
Appropriate Requirements
5.3 Cost Effectiveness
5.4 Utilization of Permanent Solutions
5.5 Preference fOT Treatment as a Principal Element
5.6 Documentation of No Significant Changes
25
26
28
29
29
29
31
31
32
33
APPENDIX A - SOIL AND GROUND-WATER REMEDIATION CRITERIA
APPENDIX B - PERFORMANCE AND COMPLIANCE MONITORING PLAN
APPENDIX C - FEDERAL AND STATE CHEMICAL AND ACTION-SPECIFIC ARARs
i i
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Table of Contents
LIST OF TABLES
TABLE
NO.
TITLE
PAGE
1
2
3
4
Soil Screening Summary
Ground-Water Screening Summary
Comparative Evaluation of Alternatives
Alternative 3a - Off-Site Landfill Disposal of Soil and Ground-Water
Treatment by Air Stripping/GAC
13
14
16
7:l
LIST OF FIGURES
FIGURE
NO. .
TITLE
FOLLOWING
PAGE NO.
1 .
2
3
Location Map
Isoconcentration Map for Vinyl Chloride in Shallow Ground Water
Isoconcentration Map for cis -1,2-DCE in Shallow Ground Water
1
7
7
iii
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DOOU oPERABLE UNIT 4
DECISION SUMMARY
FOR THE
RECORD OF DECISION
1.0 SITE NAME. LOCATION, AND DESCRIPTION
Defense Distribution Depot Ogden, Utah (DDOU) is located at 1200 South Street and 500
West in the northwest part of the City of Ogden, Weber County, Utah as depicted in Figure 1.
The DDOU facility has been a key installation in the Department of Defense (DOD) supply
system since September 15,1941.
Situated in a semi-TUral setting with the small communities of HaTrisville (population
2,500) 1.5 miles to the north, Fan West (population 1,750) 3 miles to the northwest,
numerous small ranches and a few small businesses located to the west, east, and south,
DDOU covers approximately 1,100 acres within the Great Salt Valley. A residential atea is
located approximately one-quarter mile west of Operable Unit 4 (OU 4), and the Walquist
Junior High School is located approximately one-half mile west of OU 4. Mill and Four
Mile Creeks drain the topographically flat area of the Installation and flow from east to
west.
The Depot is underlain by unconsolidated lacustrine and alluvial deposits of Quaternary
and Recent age. An unused shallow water table aquif~r, ranging in thickness from
approximately 15 to 25 feet, underlies OU 4 in the northern portion of the Depot (Figure 1).
The shallow aquifer is classified by the State of Utah as a Class II Aquifer, a potential
future source of drinking water. Ground-water flow in the shallow aquifer underlying
au 4 is toward the southwest. A deeper, confined aquifer has been encountered at a depth of
approximately 110 to 125 feet below the ground surface at OU 4. Where encountered, this
aquifer exhibits artesian conditions with water levels in the wells rising above the ground
surface. Regional studies indicate that there may be some hydraulic connection between
the shallow and deep aquifers. The strong upward gradient which currently exists could
potentially change in the future as a result of excessive pumping of ground water from the
deeper aquifers. '
In the past, both liquid and solid materials have been disposed of at DDOU. Oily liquid
materials and combustible solvents were burned in pits, and solid materials were buried,
burned, or taken off site for disposal. Several waste disposal areas have been identified on
property. currently or formerly controlled by DDOU. These areas have been divided into
four operable units. This ROD addresses Operable Unit 4.
Operable Unit 4 is composed of Burial Sites 4-A through 4-E. Analysis of soil samples
revealed tbat the soil in Burial Site 4-E is tbe primary source of ground-water
contamination. Burial Site 4-A is considered a potential secondary source. Investigations
in the other burial sites did not reveal any evidence that the materials disposed of at those
locations are contaminating tbe sballow ground water or tbe soil. In general, the
following materials or cbemicals wbich are or may be harmful to bumans and animals
have been, found in Burial Site 4-E soils: volatile organic compounds (VOCs),' semi-
volatile organic compounds (SVOCs), pesticides, polycblorinated bipben'yls (PCBs),
hydrocarbons, dioxins, and furans. The same groups of contaminants have also been
found in soils sampled from Burial Site 4-A. However, fewer compounds within each
group were detected in the Burial Site 4-A soil samples, and their concentrations were
generally lower.
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Scale in Miles
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DEFENSE DISTRIBUTION
.. DEPOT OGDEN BOUNDARY
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Ground-water monitoring results indicate the presence of a VOC contaminant plume that
originates from the vicinity of Burial Site 4-E. The 'most commonly detected compounds
within this plume are vinyl chloride (VCL) and cis-1,2-dichloroethene (cis-1,2-DCE).
These compounds are chemical degradation products of solvents known to have been
disposed of in Burial Site 4-E. Of the compounds detected in ground water beneath au 4,
vinyl chloride, cis-1,2-dichloroethene, trichloroethene (TCE), benzene, and PCBs exceed
their respective maximum contaminant level (MCL). The MCL for vinyl chloride is 2
micrograms per liter (J,J.g!L), while that of cis-1,2-DCE is 70 J,J.g!L. The MCLs for TCE,
benzene, and PCBs 'ire 5 J,J.g!L, 5 1J,g/L, and 0.5 ~, respectively.
2.0 SITE HISTORY AND ENFORCEMENT ACTIVITIES
2.1 HISTORY
Burial Site 4-A. Burial Site 4-A is enclosed by a 320-foot by 220-foot airfield mat fence and
lies near the northern boundary of the Depot (Figure 1). Analysis of aerial photographs
reveal that activity in Burial Site 4-A began during the 1950s and continued through 1975.
Within this area were two east-west, trending burning pits that measured approximately
250 feet long, 20 to 30 feet wide, and 10 feet deep. A records search indicates that solid
materials including wood, crating materials, paper, medical waste, and other debris were
burned in open trenches that were excavated to the water table. Approximately 14,000
pounds of material was disposed of in Burial Site 4-A each month. In addition, used oils
from the motor vehicle maintenance area and greases collected from degreasing
operations were disposed of in Burial Site 4-A. Approximately 40 gallons of waste oils per
day, were collected in drums and disposed of in this way.
Burial Site 4-B. Fluorescent tubes were reportedly buried in Burial Site 4-B. Although site
investigation activities have not confirmed the presence of fluorescent tubes in Burial Site
4-B, debris similar to that encountered in Burial Site 4-E have been observed. This
indicates that the disposal activities at Burial Site 4-B were either disturbed by the oil
holdinglbuming pit (Burial Site 4-E), or were conducted in the same pit. Because
fluorescent tube debris has not been observed in this area, Burial Site 4-B has been included
as part of Burial Site 4-E for cleanup purposes.
Burial Site 4-C. Burial Site 4-C, which lies approximately 50 feet BOuth of Burial Site 4-A
(Figure 1), was operated as a sanitary landfill from 1969 to 1972. Depot records indicate
that cans of jelly and jam and other sanitary waste were buried in four east-west trending
trenches measuring approximately 80 feet in length and 30 feet in width. However,
inspection of an aerial photograph taken in 1971 indicates that these trenches may have
been as long as 200 to 250 feet. Site investigations confirmed the presence of large numbers
of jam and jelly cans in this disposal area.
Burial Site 4-D. Burial Site 4-D is a rectangular area, measuring approximately 50 feet by
40 feet. Although methyl bromide cylinders were reportedly disposed of in Burial Site 4-D,
only large quantities of halazone water purification tablets contained in bottles were
encountered during the site investigation activities. This does not preclude the presence of
methyl bromide cylinders in this location. Activity in Burial Site 4-D is believed to have
begUn during the mid-1940s and continued through the mid-1960s.
Burial Site 4-E. Burial Site 4-E was used as an oil holdinglburning pit for waSte oils and
spent solvents produced from various processes on the Depot from the mid-1950s to the mid-
1960s. Aerial photographs indicate a trench of similar dimensions to those in Burial Site
4-A at this location. A records search indicates that prior to the current disposal practices
employed at DDOU, which were started in the mid-1960s, refuse, waste oils, combustible
solvents, and industrial wastes were disposed of several times a year in the oil
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holding/burning pit located at Burial Site 4-E. Solvents known to have been used at DDOU
include safety solvent FO-128 (containing methylene chloride, tetrachlor~ethene,
petroleum hydrocarbons), trichloroethene (TCE), l,l,l-trichloroethane n,l,l-TCA), ethyl
acetate, toluene, naphthalene, and turpentine. Stoddard solvent, a mixture of C7 through
C 12 hydrocarbons, was also used extensively at the Depot. No records of the volumes of
these materials disposed of in Burial Site 4-E are available. The wastes were set on fire to
provide training for the DDOU fire department as weB as to dispose of the wastes~
2.2 SCOPE AND ROLE OF OPERABLE UNIT 4
Defense Distribution Depot Ogden, Utah, with concurrence from the State of Utah DEQ and
EPA, has elected to divide the contaminated areas of DDOU into four operable units which
have common disposal activities or tYPes of contamination. The remedial actions planned
at these four operable units are, to the extent practicable, independent of one another.
Remedies have already been selected for OU 1 and OU 2. The ROD for OU 1 is under
review, while the remedy for OU 2 is being implemented. The ROD for OU 3 is being
prepared. With respect to OU 4, the role of the remedial action to be undertaken is to reduce
the principal threat posed by contaminated soil and shallow ground water that may occur
.as a result of future exposure of residents or on-Depot workers. The remedy for OU 4 is the
third final response action for this NPL site.
2.3 ENFORCEMENT HISTORY
A records search in 1979 by the US Army Toxic and Hazardous Materials Agency
identified four locations where hazardous materials might have been used, stored, treated,
or disposed of. DDOU was proposed for inclusion on the National Priorities List (NPL) in
1984 and the decision was fmalized in July of 1987. As a result, the Defense Logistics
Agency (DLA) conducted a study to determine the location of any past disposal sites and the
potential for ground-"';ater contamination resulting from those sites. On June 30, 1986,
DDOU entered into a Memorandum of Agreement with the State of Utah Department of
Health
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During the summer and fall of 1988, site characterization activities included a soil-gas
investigation, drilling and sampling of shallow and deep soil borings, installation of
shallow ground-water monitoring wells, and sampling and analysis of all monitoring
wells installed at DDOU. Site characterization included a water well survey and
development of a list of potential human, plant, and animal receptors which was used in
the preparation of an endangerment assessment. In general, results indicated the
presence of VOCs in the soil gas and ground water underlying the site.
Further site characterization activities conducted during November and December of 1989
and January of 1990 included excavation and sampling of test pits, drilling and sampling
of additional shallow soil borings, installation and sampling of several shallow ground-
water monitoring wells, surface soil sampling and analysis, and installation and
sampling of deep ground-water monitoring wells. Results of the site characterization
activities confirmed the presence ofVOCs in the shallow ground water underlying OU 4 as
far as 2,000 feet downgradient of the burial areas. No contamination was detected in
samples from the deep ground-water monitoring wells. .
Additional site characterization activities were conducted in July and August of 1990, with
the installation of more shallow ground-water monitoring wells and soil borings. PCBs,
dioxins, and furans were detected in soil samples from Burial Sites 4-A and 4-E. These
compounds are relatively immobile and generally adsorb strongly to soil particles.
V olatile organic cqmpounds, PCBs, dioxins, and furans were detected in shallow ground-
water samples. An air monitoring survey was conducted in the closest .downwind
building to OU 4. No contaminants were detected in air samples that could be attributed to
contaminants detected in the ground water at OU 4. .
Site characterization activities conducted in . April of 1991 included installation and
sampling of shaHow monitoring wens, soil borings, and sampling of selected shallow
monitoring wells in the vicinity of OU 4. Volatile organic compounds, petroleum
hydrocarbons, dioxins, and furans were detected in the soil samples. The results of this
investigation confirmed the presence, extent, and source of ground-water contamination
at au 4.
2.5 COMMUNITY RELATIONS HISTORY
The Rl/FS Report and the Proposed Plan for au 4 were released to the public on September
27, 1991 and December 6, 1991, respectively. These documents were made available to the
pubHc in both the Administrative Record and an information repository maintained at the
Weber County Library. The notice of availability for these two documents was published
in the Salt Lake Tribune, the Deseret News, and the Ogden Standard Emminer on
December 6, 7, and 8, 1991.
A public comment period (December 6, 1991 through January 6, 1992) and a public meeting
held on December 17, 1991 provided the public with opportunities to comment on the Proposed
Plan. At the public meeting, representatives from DDOU, EPA, and the State of Utah
answered questions. A court reporter prepared a transcript of the meeting, a copy of which
has been placed in the Administrative Record along with all written comments received
during the comment period. In addition, copies of the transcript were sent to all of the
meeting attendees who requested one. A response to the comments received during this
period is included in the Responsiveness Summary, which is part of this ROD. This
decision document presents the selected remedial action for OU 4, chosen in accordance
with CERCLA; as amended by SARA and, to the extent practicable, the NCP. The decision
on the selected remedy for this site is based on the Administrative Record.
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3.0 SITE CHARACTERIZATION
3.1 NATURE AND EXTENT OF CONTAMINATION
This section presents a concise and comprehensive summary of analytical data gathered
during the investigation of OU 4.
3.1.1. Nature and Extent of Soil ContAminAtion
Burial Site 4-A. Results of soil sample analyses indicate that a wide variety of
contaminants are present in the soil and debris within the bum pits at Burial Site 4-A.
Contaminants detected include VOCs, SVOCs, PCBs, pesticides, hydrocarbons, metals,
dioxins, and furans. The only VOCs detected were trans-l,2-DCE at concentrations of up to
0.04 milligrams per kilogram (mg!kg). Semi-volatile organic compounds detected
included naphthalene, phenanthrene, 2-methylphenol, 4-methylphenol, and benzoic acid
were detected at concentrations in the range of 0.4 to 2.2 mg/kg. The pesticides
dichlorodiphenyl-dichloroethane (DDD), dichlorodiphenyldichloroethene (DDE), and
dichlorodiphenyl-trichloroethane (DDT) were detected in samples from Burial Site 4-A
(0.02 to 0.3 mg/kg) as well as in soils where there was no evidence of disturbance or buried
materials in the vicinity of this burial area. PCBs were also detected at concentrations up
to 2.9 mglkg.
Elevated levels of some metals were also detected in Burial Site 4-A soils. Arsenic,
barium, cadmium, chromium, lead, mercury, silver, and zinc exceeded background
concentrations established for the DDOU area. Zinc was detected at the highest
concentration (2,600 mglkg). Analyses of the extract from the Extraction Procedure (EP)
Toxicity test detected only barium but at concentrations less than the EP Toxicity limit of
100 milligrams per liter (mg!L). .
Oil and grease were detected in soil samples at concentrations ranging from 140 to 530
mg/kg. Dioxin and furan isomers were detected at concentrations reported in picograms
per gram (pglg) or parts per trillion. The source of dioxins and furans in the test pits is
most likely a result of combustion of wood and paper products, plastics, and plastic
insulation on electrical wiring disposed of at Burial Site 4-A
Toxicity Characteristics Leaching Procedure (TCLP) analyses indicate that the soil and
debris in Burial Site 4-A do not exhibit the Resource Conservation and Recovery Act
(RCRA) toxicity characteristics, and do not exceed FOOI-FOOS listed waste treatment
standards. The volume of contaminated soil in Burial Site 4-A is estimated at 3,000 cubic
yards based on the known dimensions of the burial site and depth of contamination.
Burial Site 4-C. The material encountered in Burial Site 4-C is consistent with the reported
use of Burial Site 4-C as a sanitary landfill. The VOCs cis-l,2-DCE and 1,1-DCE were
detected in soil samples at concentrations less than 0.01 mg/kg. The only SVOC detected
was di-n-butylphthalate. The pesticides DDE and DDT were detected at concentrations
simila~ to background levels. Barium, cadmium, lead, mercury, silver, and zinc were
detected at concentrations above background levels. Zinc was detected at the highest
concentration (350 mg/kg). Analyses of the extract from the EP Toxicity test detected only
barium but at concentrations below the EP Toxicity limit for barium.
On the basis of the interpretation of the soil and ground-water analytical dat.a obtained
during the site investigations, the soils in this area were not considered to be a source of the
ground-water contamination observed at OU 4.
-5-
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Burial Site 4-D. Test pit excavations at this site revealed large quantities of water
purification tablet bottles located approximately 4 to 6 feet below the ground surface. No
VOCs, BNAEs, PCBs, or pesticides were detected. No methyl bromide cylinders were
observed. despite the reported disposal of these items in Burial Site 4-D. Only arsenic
exceeded its background concentration. EP toxicity analyses detected only barium but at
concentrations weB below its EP Toxicity limit.
On the basis of this information, Burial Site 4-D was not considered a potential source of
cont,aminants found in the ground water beneath au 4. The volume of material
containing water purification tablets is unknown at this time. However, based on the area
of Burial Site 4-D and assuming the bottles are in a two foot thick layer, the volume of
material could be. approximately 400 cubic yards.
Burial Site 4-E. Oil-covered sands and silts were encountered from 6 to 8 f~et and elevated
organic vapor readings were measured in this material. Contaminants detected in the
soil and debris in Burial Site 4-E include benzene, ethylben~ene, tetrachloroethene, cis-1,2-
DCE, toluene, trichloroethene (TCE), m,p-xylene, and b-xylene at concentrations up to 82
mg/kg. The SVOCs naphthalene, 2-methylnaphthalene, phenanthrene, and 1,2,4-
trichlorobenzene were also detected at concentrations in the mg/kg range. The pesticides
DDD and DDE were detected at concentrations similar to those in background samples.
The PCB Arochlor 1260 was also detected at concentrations up to 15 mg/kg.
Background concentrations were exceeded for some metals, namely cadmium, lead,
mercury, nickel, and zinc. Lead was detected at the highest concentration (1,400 mg/kg).
Beryllium was also analyzed because of its association with the fluorescent tubes suspected
of being disposed of in Burial Site 4-B. Although beryllium was detected in two samples, .it
was also detected at similar levels in background soil samples. EP Toxicity analyses
detected only barium but at concentrations less than the EP Toxicity limit.
Petroleum hydrocarbons were analYzed to investigate the observed hydrocarbon staining
of soils. Hydrocarbons were detected at concentrations of up to 43,000 mg/kg.
Dioxin and furan isomers were detected at concentrations in the picogram per gram (pg/g)
01" part per trillion range in Burial Site 4-E samples. These compounds probably
originated as residue from burned debris and chlorinated organics in the bum pit. In
terms of an equivalent concentration of 2, 3, 7, 8 tetrachlorodibenzo-p-dioxin (TCDD), all
the dioxin and furan isomers detected in the most contaminated sample produced a
concentration of 0.067 ~g using the EPA 1987 total equivalency factors.
Some samples bm Burial Site 4-E were analyzed for TCLP toxicity and Fool-F005 listed
waste TCLP extract contaminants. Only ethylbenzene (0.14 mgIL) and xylene
(0.47 mg/L) were detected at concentrations in excess of the TCLP extract limit for this
constituent for F001-FOOS listed wastes. Dioxins and furans were also analyzed in the
TCLP extract but were not detected. The volume of contaminated soil in Burial Site 4-E is
estimated at 1,500 cubic yards based on the kno~ dimensions of the burial site and depth of
contamination. '
3.1.2 Nature and Extent of Ground-Water Conblft'l1wation.
. .
No contaminants were detected in ground-water sampled from monitoring wells installed
in the deep aquifer. A zone of elevated vinyl chloride and cis-l,2-DCE concentrations
appears to be centered around Burial Sites 4-A and 4-E, the major sour.ces of contaminants
in shallow ground water at OU 4. No evidence of a dense non-aqueous phase liquid
(DNAPL) was detected in the shallow aquifer beneath au 4. The nature and extent of
contaminants detected in ground water is discussed below.
-6-
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Volatile Organic Compounds. The most widespread contaminants detected in the shallow
ground water at au 4 are the vacs vinyl chloride and cis-l,2-dichloroethene. Both
compounds were detected at concentrations in excess of their respective MCL (2 ~ fOT
vinyl chloride and 70 ~ fOT cis-1,2-DCE). The total areal extent of the zone of ground
water containing vinyl chloride at concentrations above 2 ~ is depicted in Figure 2 and
is estimated to be 50 acres. The total volume of ground water within this area is estimated
to be approximately 65 mi1)ion gallons based on the assumption that the entire saturated
- thickness of the aquifer is contaminated within the defined area. The volume of ground
water contaminated by cis-l,2-DCE in excess of its MCL is depicted in Figure 3 anJ is
contained within the vinyl chloride plume.
Trichloroethene concentrations exceeded the MCL of 5 ~ in only one sample (17 ~)
and benzene was detected in two samples at a concentration ex~eding its MCL of 5 ~
(up to 30 ~). ather vacs detected in shallow ground water at au 4 include ethylbenzene
(150 IJ.WL), toluene (34 ~), trans-1,2-dichloroethene (0.7 ~), l,2-dichlorobenzene (up
to 36 ~), 1,4-dichlorobenzene. (up to 31 ~), 1,1-dichloroethane (0.8 ~), and o-xylene
(150 ~/L). All these contaminants were detected within the vinyl chloride plume
described above.
Semi-Volatile Organic Compounds. Although several svacs were detected in sh8Ilow
ground water at au 4, none of the contaminants exceed their respective MCLs. Compounds-
detected include 1,2-dichlorobenzene (up to 30 IJ.WL), 1,3-dichlorobenzene (up to 28 ~),
and 1,4-dichlorobenzene (up to 26 ~). Naphthalene (up to 92 J,Ig/L), phenanthrene (up to
36 J,Ig/L), 1,2,4-trichlorobenzene (up to 26 ~), and 2-methylnaphthalene (up to 150 ~)
were also detected. Pentachlorophenol (40 JLg/L), 2-methylphenol (up to 97 ~L),
4-methylphenol (up to 77J,Ig/L), 2-4 dimethyl phenol (15 ~), and dibenzofuran (12 ~)
were also detected.
PCBs. Polychlorinated biphenyls were detected at levels above the MCL- of 0.5 J.LgIL in
ground water. The concentrations detected (up to 130 ~) are greater than the solubility
limit for PCBs, estimated to be 0.4 J,1g/L to 3.0 J.LgIL for PCB Arochlor 1260. This suggests
that the PCBs may actually be adsorbed on the particulates contained in the ground-water
samples, rather than dissolved in the ground water. This conclusion is supported by the
lack of PCBs in low turbidity samples col1ected during a subsequent sampling round.
Dissolved Metals. Dissolved metals detected in the shallow ground water underlying
au 4 include arsenic, barium, lead, and zinc, but the only metal to exceed its MCL of 0.01
mg/L was cadmium (0.029 mg/L) and only in one sample.
Hydrocarbons. Petroleum hydrocarbons were detected -in ground water at concentrations
of up to 43,000J,1g/L near Burial Site 4-E.
Dioms and F1U'BD8. Dioxins and furans were detected in sediment-laden ground-water
samples at concentrations of up to 0.000085 J.LgIL equivalent concentration of TCDD. The
detecti~m of dioxins and furans in ground-water samples has been attributed to adsorption
of the dioxins and furans to silt particles in the shallow aquifeJ' that weJ'e entrained in the
turbid samples. -
3.2 PUBLIC HEALTH AND ENVIRONMENTAL IMPAcrs
A baseline risk assessment was conducted for au 4 following completion of the site
characterization activities. The purpose of the assessment was to determine the most
significant contaminants present at au 4, the different ways by which people, plants, and
animals would potentially come into contact with the contaminants, and the probability of
-7-
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@
i
;.
8JMM-44
(NA)
.
. Shallow monitoring well location
EXPLANATION
"
Isoconcentration line (~); contour
interval varies; contour lines are
dashed where inferred
Maximum contaminant level
JMM-23 We" number
(23)
Concentration (~IL)
Concentration less than detection limit
shown (~/L)
MCL
DDOU
Defense Distribution Depot Ogden, Utah
«1)
Note: All samples were collected in April 1991
ISOCONCENTRA TlON MAP
FOR VINYL CHLORIDE IN
SHALLOW GROUND WATER
FIGURE 2
-------
@
. i
: ~
j !
i !
: ~
.
JMM-44
NA
o
.
. Shallow monitoring well location
EXPLANATION
"
Isoconcentration line (~); contour
interval varies; contour lines are
dashed where inferred
Maximum contaminant level
JMM-23 Well number
(23)
Concentration (~)
Concentration less than detection limit
shown (J.19/L)
MCL
DDOU
Defense Distribution Depot Ogden. Utah
«1)
Note: All samples were collected in April 1991
ISOCONCENTRA TlON MAP
FOR CIS -1,2. DCE IN
SHALLOW GROUND WATER
FIGURE 3 .
-------
any harmful effects occurring as a result of that contact. Based on the results of the
baseline risk assessment, the media of concern for OU 4 were determined to be the ground
water underlying OU 4 and the soil and debris within Burial Sites 4-A and 4-E. Surface
water was not considered a medium of concern for OU 4. The most recent round of
sampling analytical results indicated that there is not a significant difference between
upstream and downstream contaminant concentrations in surface water. and sediments.
The upstream sampling point was outside the Depot.
3.2.1 Contaminant Identification
The initial step of the risk assessment was the selection of contaminants of concern.
COTltaminants of concern were selected for each potential route of exposure and according
to their potential for causing carcinogenic and non-carcinogenic health effects. The
contaminants of concern were selected on the basis of an index calculated as the product of
their maximum .measured concentrations in the medium of concern and their toxicity.
Toxicity was measured by the slope factor and the reciprocal of the reference dose for
carcinogenic and noncarcinogenic health effects, respectively. Also included as a
criterion was the frequency of detection. The contaminants of concern in soil for au 4 are
PCB Arochlor 1260, naphthalene, benzene, cis-1,2-dichloroethene, tetrachloroethene,
trichloroethene, arsenic, barium, cadmium chromium, lead, mercury, zinc, and TCDD.
The contaminants of concern for shallow ground water are vinyl chloride, benzene, cis-
1,2-DCE, PCB Arochlor 1260, TCDD, and arsenic.
3.2.2 Exposure~t
There are no current exposure pathways that are considered complete at au 4. The only
significant potential future exposures to au 4 contaminants are for off-site and on-site
residents who may use shallow ground water from a well installed in the au 4 ground-
water contaminant plume or on-site residents who may consume crops or livestock exposed
to contaminated ground water through the food chain. Potentially complete future exposure
scenarios for soil include exposure of construction workers to dioxins, furans, and metals
during " excavation activities in soil and debris from Burial Sites 4-A and 4-E. Although
ingestion of soil by future residents, including children, was not quantitatively evaluated,
this exposure scenario could potentially be significant. .
Contaminant concentrations and chronic daily intakes have not been reported here
because the remedy for au 4 has been selected on the basis of ARARs for ground water and
the prevention. of future ground-water contamination for soil, rather than on the results of
the risk assessment. Consequently, these details are not considered relevant to this ROD.
However, the contaminants of concern, maximum concentrations, and associated risks
for soil and ground water at au 4 are presented in Appendix A.
3.2.3 Tcmicity Aa~t
Cancer slope factors have been developed by EPA for estimating excess lifetime cancer
risks associated with exposure to potentially carcinogenic chemicals. Reference doses
have been developed by EP A for indicating the potential for adverse health effects from
exposure to chemicals exhibiting noncarcinogenic effects. Slope factors were . available for
all carcinogens except for PCB. Arochlor 1260 and TCDD, which did not have inhalation
slope factors for use in evaluating the risks associated with construction workers inhaling
contaminated dust. No reference doses were available for lead, PCB Arachlor 1260, and
TCDD. In addition, no inhalation reference doses were available for tetrachloroethene,
trichloroethene, cis-1,2-dichloroethene, naphthalene, arsenic, cadmium, mercury, and
zinc. Reference doses, slope factors, and their sources are not presented in this document
because the selected remedy was not based on the risk assessment results.
-8.
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3.2.4 Risk Characterization
Excess lifetime cancer risks (sometimes referred to as carcinogenic risks) are
determined by multiplying the intake by the cancer slope factor. These risks are
probabilities that are generally expressed in scientific notation (e.g., 1 x 10-6). An excess
lifetime cancer risk of 1 x 10-6 indicates that, as a plausible upper bound, an individual has
a one in one million chance of developing cancer as a result of chronic site-related
exposure to carcinogens over a 70-year lifetime under the specific eTposure conditions at
the site. According to the NCP, the target risk level for a site is 1 x 10-6, although a value in
the range of 1 x 10-4 to 1 x 10-6 is acceptable.
Potential concern for noncarcinogenic effects of a single .contaminant in a single
medium is expressed as the hazard quotient. The hazard quotient is the ratio of the
estimated intake derived from the contaminant concentration in a given medium to the
contaminant's reference dose. By adding the hazard quotients for aU contaminants
within a medium and across an media to which a given population may reasonably be
exposed, a hazard index can be generated. A total hazard index greater than 1 indicates
that there may be a concern for potential health effects, while a total hazard index less than
1 indicates that the concern for potential health effects is low.
The potential carcinogenic risk to future off-site residents who use the shallow ground
water at the western boundary of the Depot for 30 years is on the order of 3 x 10-3, if the center
of the current plume moves close to the boundary. The total hazard index for
noncarcinogenic effects to those future off-site residents under these conditions is on the
order of 70. These are worst case estimates based on all contaminants detected in ground
water. The calculations assume contaminant concentratio~s in excess of MCLs. The
estimated carcinogenic risk to potential future on-site residents is on the order .of 8 x 10-3,
and the total hazard index is estimated as 300. These are significant risks. The potential
carcinogenic and non-carcinogenic risks to future on-depot construction workers. who
become exposed to contaminated soils in Burial Sites 4-A and 4-E over a period of two years
are 1 x 10-5 and 0.1 respectively.
In addition to potential exposure to contaminants in the soil at OU 4, there exists a potential
for future exposure to the contents of the water purification tablet bottles in Burial Site 4-D.
The risk associated with this exposure was evaluated qualitatively because tablets are
contained in sealed glass bottles and are not present in the soil. Because the tablets are
intended to be used with drinking water, health effects would not be expected from low
doses. However, the future health risk due to exposure to the contents of the water
purification tablet bottles could cause illness or death in a child. For this reason, remedial
alternatives developed for OU 4 included the water purification tablet bottles in Burial'Site
4-D to remove this potential exposure pathway. .
No current significant environmental threats appear to be associated with OU 4. The only
area where ecological receptors could possibly come into contact with contaminants is
through the water and sediments of Four Mile Creek. Concentrations of metals in Four
Mile Creek sediments and surface water are similar in samples taken upstream and
downstream of au 4, and the contaminants associated with disposal activities at au 4 have
not been detected in surface water or sediments. It appears that contaminants present at
OU 4 have not affected Four Mile Creek. Therefore, this media was not considered during
development of the remedy for'OU 4.
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3.2.5 Uncertainties
The primary uncertainty associated with the exposure pathway of greatest concern, use of
ground water by future on-site or off-site residents, is whether or not the pathway will
become complete in the future. A second uncertainty is associated with the fact that all of
the estimates of the total hazard index for exposure through ground water are incomplete,
and therefore potentially low due to a lack of reference doses for some compounds.
Additional uncertainty is related to the assumption that on-site contaminant
concentrations will remain constant with time and unknowns associated with dermal
uptake of some contaminants of concern. With respect to exposure to contaminated soil,
there is uncertainty associated with the estimate of dust inhalation and Ingestion rates,
and the bioavailability of contaminants. In addition, the relative risks under the
residential".scenario may be greater than those calculated under the construction worker
scenario. The irrigation exposure scenario considered the uptake of dioxins and furans
into meat ana milk but not into vegetables because biotransfer factors for uptake in
vegetables could not be located.
3.2.6 Sn-.:r'ft"Ulry of Site Risks
There are no current significant risks to human health and the environment from
exposure to soil or ground water at OU 4, nor are significant risks likely to develop in the
future as long as the Depot remains in existence. Under future resident site use conditions,
risks may exceed EPA's point of departure of 10-6 cancer risk or total hazard index of 1. In
addition, Burial Sites 4-A and 4-E are the source of the contamination detected in the
shallow ground water. Consequently, actual or threatened releases of hazardous
substances from this site, if not addressed by implementing the response action selected in
this ROD, may present an imminent and substantial danger to public health, welfare, or
the .environmen t.
4.0 ALTERNATIVES EVALUATION
As part of the DDOU OU 4 feasibility study, five soil and two ground water. remedial
altematives were developed. Under Section 121 of SARA. the selected remedial action
must be protective of human health and the environment, cost effective, and attain Federal
and State applicable or relevant and appropriate requirements (ARARs). The selected
altemative must also use permanent solutions" and altemative treatment or resource
recovery technologies to the maximum extent practicable. Remedies that employ treatment
which permanently and significantly reduces the mobility, toxicity, or volume of
hazardous substances is a statutory preference. This section summarizes how the remedy
selection process for OU 4 addressed these requirements.
4.1 DEVELOPMENT OF PRELIMINARY ALTERNATIVES
The principal threats posed by OU 4 are the potential exposure of future residents or
construction workers to contaminants in Burial Sites 4-A and 4-E, the water purification
tablets in Burial Site 4-D, and ground water contam.inated by VOCs. Therefore, the
primary concem for soil remediation is to remove, reduce or control these principal
threats. Preliminary altematives that represent the range of available remediation
options for soil and ground water were developed starting with the no actIon altemative.
Subsequent altematives represented an increased degree of technical complexitY.
The main featut:es of the preliminary altematives for soil were:
1.
No Action. No remedial action would be taken to reduce the levels of
contamination in the soil at OU 4.
-10-
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2.
Institutional Controls - Legal and administrative actions would be imposed
to limit potential exposure under both current and future use scenarios. For
example, construction or excavation within the contaminated areas would
not be permitted.
3.
Containment - The potential for migration of contaminants from soil to
ground water would be reduced by controlling infiltration through
installation of a cap over the soils and debris in Burial Sites 4-A and 4-E,
and containment by a slurry cut-off wall intercepting the aquitard
underlying the shallow ground-water aquifer at OU 4. A second method of
achieving containment of the contaminated soil and water purification
tablet bottles would be to excavate these materials and place them in an on-
site Resource Conservation and Recovery Act (RCRA) hazardous waste
landfill.
4.
Off-Site Soil Disposal - Contaminated soil and water purification tablet
bottles would be excavated and transported off site for incineration or for
disposal in a RCRA permitted landfill in compliance with land disposal
restrictions.
5.
On-Site Soil Treatment - Contaminated soil would be excavated and treated
on site using chemical or incineration technologies and then returned to the
excavation if the treatment residue is suitable for this mode of disposal. If
not, the residue would be removed, along with the water purification tablets,
to an off-site RCRA permitted landfill.
6.
In-Situ Soil Treatment - Contaminated soil would be immobilized in place
using soil vitrification technology. Water purification tablets would be
excavated and placed in the treatment area.
Removal of the VOCs vinyl chloride and cis-l,2-DCE is the primary concern for ground-
water remediation. If contaminants including PCBs, dioxins, and furans are detected in
the effluent from the treatment process at levels that present a total excess cancer risk
greater than one in one mIlion, they will be removed.
The main features of the preliminary alternatives for ground water were:
1.
No Action - Ground-water monitoring would be continued (this is an
element common to all alternatives), but no remedial actions would be
taken to reduce the levels of contamination in the shallow ground water.
2."
IDstitutional Controls. Legal and administrative actions would be taken,
as necessary, to limit potential exposures under both the current and future
use scenarios. For example, steps would be taken to block out. water rights
for on-Depot--and off-Depot areas downgradient of OU 4 to prevent the
possible future use of shallow ground water.
3.
Containment - Contaminant migration potential would be reduced by
controlling ground-water movement by installing" upgradient subsurface
barriers at the northeast end of the contaminant plume.
-11-
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4,
Granulated Activated Carbon
-------
TABLE 1
SOIL SCREENING SUMMARY
Alternative Eft'ec:tJvenM8 ImpiementabWty QJIIt Selected Commenta
1. No ActIon Poor Excellent Excellent Yes Repre8ents balll!lIne COlli! for comparison.
Doe8 not prevent continuing contamination of shallow ground waler.
I. lnadtudonal Contn18 Poor Excellent Excellent No Afford8 non-lnva8lve exposure control.
Doe8 not prevent continuing contarnJnatlon of shallow ground waler.
S. Containment
. SIIIIT)' Wall and ClIp Fair Good Good No IfIgh maintenance.
Restrlct8 future 81le UBI!.
On,slte Landfill FacWt1 Good Good Good Ye8 Clean cl08ure.
Requlre8 on-going monitoring of land"".
4. OIr-Slte SoU TrMtmen~
I . incineration Excellent Poor Poor Yee EllrnJnatee 80urce, but cost Is high.
....
~ Clean doeure.
.
Acceptable to SlolelEPA because It Is the be8t demonstrftled aV811ftbie
technology (BOAT) for dioxin de8tructlon.
No facility currently permitted for dioxin destruction.
. Landfill Good Good Good Yes Ellmlnate8 80Urce.
Dependent on RCRA cla8s\1lcatlon of 80il.
Clean cl08ure.
8. On-S\te SOU Tnatment
. Deddorbultlon Good Fair Fair Yee Requlre8 treatabl!lty le8te and Ie an Innovative technology.
No air ernJeslone.
Clean cloeure.
. Inclneratlon Good Poor Fair Yes Implementation may be dUficult due to air emi8slons and dioxlnJfurftn
content.
Clean cloeure.
No facility t:urrenlly. available for dioxin de8tructlon.
8. In-Sltu Soli n-tmen~
Vltriftcatlon Fair Fair Fair No Some que8t1on8 regarding overall effectlvene88 of vitrlficfttion pWt"ess
and migration of contamlnant8 Into partially vitrified soll9.
Preconditioning of 80118 required.
-------
TABLE 2
GROUNO-WATERSCREENlNG SUMMARY
Alternative Elrec:tlveneu ImplementabWty Co6t Selected Comments
.. No Aedon Poor Excellent Excellent Ycs Represents baseline case for comparison.
I. Irwdtudonal CordrcJI Poor Excellent Excellent No AlTords exposure control.
May be required based on future land usc.
Does not eliminate problem.
3. Containment Fair Good Good No Technically difficult and costly comparcd to cquolly
effective options.
Does not reduce contaminants to bclow MCL.'I.
.e. CAC Good Good Fair No High costs.
High consumption of GAC without prc.trentmcnl.
I. AIr Bkfw-'GAC Excellent Good Fair Ycs Uscs proven technology for ground watcr.
, Provides reduction In mobility, toxicity and volumc of
.... contaminated ground water. Efficient use of technologies
~
. to reduce treatment cosls.
.. 8team8b.~ Excellent Fair Fair No Steam stripping systems not as rcadily availablc 09 air
stripping IIYlltems.
Would require major enginecring dcsign crfort.
Costs higher than air stripping with minor bencfits.
'I. UVlOzone Good Good Fair Yes Unprovcn technology will requirc trcatability h,.ting.
offers no significant advantage ovcr proven technoloKics.
Wide range of contaminants may make technical
Implementation difficult.
Presence of 011 and grease minimlzcs crfcctivcness.
No permitting necesllary for air emissions.
Innovative technology warrants furthcr co'n.idcratinn.
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Alternative 6a
- Off-Site Soil Disposal and Ground-Water Treatment by
UV/Ozone.
Alteruative 6b
- Off-Site Soil Incineration and Ground-Water Treatment by
UV /Ozone.
Alternative 7a
- On-Site Soil Treatment by Dechlorination and Ground-Water
Treatment by UV/Ozone.
Alteruative 7b
- On-Site Soil Treatment by Incineration and Ground-Water
Treatment by UV/Ozone.
4.3 DESCRIPrlON OF ALTERNATIVES
4.3.1. Alternative 1 - No Action
The only activity that would occur under the no action alternative is monitoring of ground-
water quality. Annual ground-water samples would be collected from 10 wells at OU 4 and
analyzed for VOCs, PCBs, and total hydrocarbons for a period of at least 20 years. Samples
from three of the 10 wells would also be analyzed for dioxins and furans. Alternative 1.
does not reduce the principal threats to human health and the environment at OU 4. The no
action alternative is not required to comply with ARARs. The indirect, capital, operating
and maintenance costs associated with this alternative are presented in Table 3, as are
estimates of present net worth costs. Based on a 20 year monitoring period and a statutory
review every five years, the present net worth of this alternative is $286,000.
4.3.2. Alternative 2 - ContR.lynnpnt of ContsnmnJlted Soil and Ground-Water Treatment
by AU- Stripping and GAC
Approximately 4,500 cubic yards of contaminated soil in Burial Sites 4-A and 4-E, and;
water purification tablets from Burial Site 4-D, would be excavated and placed in anon-~
RCRA hazardous wasteJandfill~ Excavation would continue until soils remaining 00 site
contain less than 25 mglkg of PCBs as recommended by EPA Directive 9355.4-01FS, less
than 1 ~g total equivalent 2,3,7,8, tetrachlorodibenzo-p-dioxin as recommended by the
Dioxin Disposal Advisory Group, and pres~nt a health risk of less than one in ten
thousand, with a target of one in one million. .If methyl bromide cylinders were
encountered in Burial Site 4-D, they would be removed, treated, and disposed of by a
commercial operator. The excavations would be backfilled with clean fill, topsoiled and
revegetated. This remedial action would be completed within 15 to 24 months after the ROD
is signed.
Land disposal would comply with the RCRA land disposal restrictions (40 CFR Part 268)
for FOOl through FOOSlisted wastes, the requirements of 40 CFR Part 761 for PCBs and the
requirements of Utah.Administrative Code (UAC) Rule 450 that are considered relevant
and appropriate. During excavation of the soils, TCLP tests would be performed
periodically to confirm the characteristics of the waste and compliance with land disposal
restrictions. If soils fail the treatment standard for FOOl through FOO5 listed wastes, they
will be treated to achieve compliance by aeration or stabilizationlfixation prior to land
disposal. The RCRA listing for dioxin wastes or treatment residue would not apply to the
soils in OU 4 because the dioxin and furan contamination did not originate from any of the
sources listed in 40 CFR Part 261. However, it is relevant and appropriate to adopt the
treatment standards for dioxin and furan listed wastes because these soils contain dioxins
and furans. The soil and debris would be monitored to ensure that dioxin and furan
concentrations in the TCLP extract are less than 1 ~g for each of the tetra, penta, and
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TABLE S
COMPARATIVE EVALUATION OF AI.TERNATIVES
Evaluation AI~...atl... 1 Altftnatl... S AJb!rn8t1VI!I Sa Altlnuod... .. AI~...adVll4. AI~madve4b Altemadve II Altemadve Sa Allrmlldve 6b Allrmadve'1a Allrmadve'1b
CrIteria l'IoAdlon On.8I~ Otr.8Ite orr.8I~ ,On.SlLe On.Slte On-Slte OIl'.lIte OIl'.Slte On.Slte On.Slte
Coatalnmentl Landfill/Air Inc:lnerattonl Deeh1orlnattonl Inc:lneratton! Containment! Landfllli Incineration! Dechlorination Indneradon
Air Btrlppln. Btrlppin. Air Strippln. Air Strippln. Air Strippln" UVIOzono UVlOzone UVlOzone UVlOzone UVIOr.one
OAC mc mc CAC mc
'J1Ireahoid CrIteria
I. Prote.Uyeno.. 4 . . . . . . . . . .
I. ARARa 4 . . . . . . . . . .
Balaac:ID. Ctt~rla
S, Lonl.T.rm EIT..Uyonea. 4 0 0 . . . 0 0 . . .
4. Reol...Uon of MTV 4 0 0 . . . 0 0 . . .
S. Short.Torm EITecUy.ne.. . 0 0 0 0 0 0 0 0 0 0
8. Implomontabllily . 4 . 4 0 0 l!. 0 l!. 0 0
7. eo.t:
,
....
Q) In 011...., Cool8 " r.mo,ooo $340,000 $340,000 S640,OOO $490,000 $285,000 $345,000 $345,000 $.'>45.000 $oI!lS.IU'
.
Capital Coote " '1,380,000 82,3JO,ooo . 818,r,oo,ooo 85,000,000 85..'m,OOO .. ,530,000 $2,350,000 816,700,000 $5,200,000 $5,450,000
Operation anol Malntenan.. fM),r,oo 82114,000 SZS.ooo 8229,000 8229,000 8229,000 $241,000 $218,000 $216,000 $216,000 $:i16,OIlO
11- Yoar Pre...nt Worth 8113,000 83,000,000 "1,IlOO,000 818,000,000 sIJ,800.ooo $7,000,000 $.1,100,000 $3,900,000 $18,000,000 $6,9IM',IU' $1,IIM','U'
IO-Year Pr_n' WOI'th '188,000 83,IlOO,000 $4,500,000 819,000,000 S7 ,500.000 S7 ,800,000 $3,900,000 "',600,000 819,000,000 '7,600,000 $1,81JU,IMJO
2O-Year Pr_n' Worth ",000
. Moot. n-ilorion
0 ParU.lly mool8 .rllorlon
4 0.-'110' meet nilorlon
-------
hexa-dioxin and furan isomers prior to land disposal as recommended for dioxin listed
wastes in 40 CFR 268. The construction and operation of the landfiU would comply with 40
CFR Part 264 and the equivalent State regulations defined in Utah Administrative Code
(UAC) Rule 450. Closure and post closure would bein accordance with the requirements of
40 CFR Part 264 and the equivalent State regulation (UAC Rule 450). All activities carned
out as part of the remedial action would comply with the requirements of the Occupational
Safety and Health Act (29 CFR 1910) and the equivalent State regulation in UAC Rule 500.
Ground water in the Class II shallow aquifer at au 4 would be extracted through a
sufficient number of extraction wells to achieve a flow rate of up to 150 gallons per minute.
The ground water would then be pumped to an air stripper to remove vinyl chloride, cis-l,2-
DCE, benzene, and TCE to levels below their MCLs. If PCB concentrations in the effluent
exceed the MCL for PCBs of 0.5 ~, or if dioxins and furans exceed the proposed MCL for
dioxins and furans of 5 x 10-5 11g/L, a GAC unit would be added for removal of these
contaminants. Treated ground water would be reinjected into the aquifer around the
perimeter of the contaminant plume using injection wells or infiltration galleries. The
extraction and reinjection system would comply with the Federal underground injection
regulations (40 CFR Parts 144-147) and the State well drilling standards ofUAC Rule 625-
4.
Ground-water remediation would eventually reduce the health-based risks to one in ten
thousand with a target level of one in one million and' achieve MCLs which are considered
to be ARARs within the area of attainment defin,ed by the 2 11g/L vinyl chloride
concentration contour. The time frame required for compliance with ground-water
cleanup criteria is estimated to be a minimum of five years, assuming treatment of a
minimum of five pore volumes (approximately 330 million gallons) will be necessary to
attain ARARs. However, the ability of the pump and treat approach to achieve very low
residuals (less than 2 J,LgIL for vinyl chloride) in ground water may be limited, as
evidenced by EPA experience with other sites where standard extraction systems are often
not suitable for removing all of the contaminants present in the aquifer material. .
The air stripper vapor emissions are expected to be less than the Utah ARAR for air
emissions which is 1.5 tons of total VOCs per year
-------
The indirect, capital, and operation and maintenance costs associated with this
alternative are presented in Table 3. Due to the uncertainty associated with the ground-
water remediation time frame, the present worth cost of this alternative has been assessed
based on both 5-year and lO-year ground-water remediation time frames. The costs have
been estimated at $3.0 million and $3.9 million, respectively.
4.3.3. Alternative Sa - Off-Site Soil Disposal and Ground-Water Treatment by Air
StI: ippAdg and GAC
Approximately 4,500 cubic yards of contaminated soil in Burial Sites 4-A and 4-E would be
excavated and transported off-site for placement in a RCRA hazardous waste landfill.
Water purification tablets from Burial Site 4-D would be transported off-site for placement
in a RCM industrial landfill because this material is neither. a RCRA listed hazardous or
characteristic waste. Excavation would continue until soils remaining on site contain
less than 25 mg/kg of PCBs as recommended by EPA Directive 9355.4-01FS, less than 1
J,Lg/kg total equivalent 2,3,7,8, tetrachlorodibenzo-p-dioxin as recommended by the. Dioxin
Disposal Advisory Group, and present a health risk of less than one in ten thousand, with a
target of one in one million. If methyl bromide cylinders are encountered in Burial Site
4-D, they will be removed, treated, and disposed of by a commercial operator. The
excavations would be backfilled with clean fill, topsoiled, and revegetated. This remedial
action would be completed within 15 to 24 months after the ROD is signed, and would result
in clean closure of the site. .
Land disposal of material from Burial Sites 4-A and 4-E would comply with the RCRA land
. disposal restrictions (40 CFR Part 268) for FOOl through F005 listed wastes, tbe
requirements of 40 CFR Part 761 for PCBs, and the requirements ofUAC Rule 450 that are
. considered applicable. During excavation of tbe soils, TCLP testa will be performed
periodically to confirm the characteristics of the waste and compliance with land disposal
restrictions for FOOl through FOO5 listed wastes. If tTeatment is required to achieve
compliance with treatment standards, this would be carried out by the receiving facility.
The soil and debris would also be sampled to ensure that dioxin and furan concentrations
in the TCLP extract are less than 1 JJg/kg for each of the tetra, penta, and hexa-dioxin and
furan isomers prior to land disposal that is required for dioxin wastes under 40 CFR Part
268. If soils fail this criteria, the failing material would be transported to a commercial
incineration facility for tTeatment in compliance with 40 CFR Part 264, Subpart 0, prior to
landfill disposal. While no incineration facilities are currently permitted for destruction
of material containing dioxins and furans, storage of material at the facility can be
undertaken until permitting. is completed. Land disposal of the water purification tablets
would be in compliance with 40 CFR Part 24L
Transportation of material off site would comply with the requirements of 40 CFR Part 263,
49 CFR Parts 107, 171 thrOugh 177. Operation of the RCRA hazardous waste and industrial
landfills would comply with 40 CFR Part 264 and the State equivalent regulations defined
in UAC Rule 460 which are considered applicable. Land diliposal of the water purification
tablets from Burial Site 4-D wOuld be comply with the reqairements of 40 CFR 241, Title 19:
Chapter 6 of the Utah Code Annotated. and UAC Rule 450-301. The time frame for this
remedial action would be in the order of a few weeks to a few months after co~encement
of the remedial action and would be complete within 15 to 24 months after the ROD is
signed. . .
Ground water would be pumped to an air stripper to remove VOCs, and to a GAC unit, if
necessary, for removal of PCBs, dioxins, and furans as described for Alternative 2. The
implementation of this ground-water remediation alternative would eventually reduce the
health-based risks to between one in ten thousand and one in one million. Compliance
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with ground-water and air emissions ARARs has been discussed under Alternative 2.
The indirect, capital, operating and maintenance costs associated with this alternative are
presented in Table 3. Due to the uncertainty associated with the ground-water remediation
time frame, the present worth of this alternative has been estimated based on both a 5-year
and lO-year ground-water remediation time frame at $3.8 million and $4.5 million,
respectively. .
.;"
4.3.4. Alternative 3b. Off.Site Soil Incineration and Ground.Water Treatment by Air
Stripping and GAC
Contaminated soil in Burial Sites 4-A and 4-E would be excavated as described under
Alternative 3a and transported to an off-site facility for incineration. Water purification
tablets from Burial Site 4-D would'be excavated and transported to an off. site facility for
placement in a RCRA industrial landfill as described under Alternative 3a. The
incinerator would be permitted for dioxin and furan destruction and achieve 99.9999
percent destruction and removal efficiency. It is not applicable to classify these soils as
RCRA dioxin-listed wastes or treatment residues because the dioxin and furan
contamination did not originate from any of the sources listed in 40 CFR Part 261.
Although it is relevant and appropriate to use the best available demonstrated technology
(BDAT) for the destruction of dioxins, which is incineration, it is not relevant and
appropriate to use the 99.9999 percent treatment standard for soils that contain FOOl through
F005 listed wastes. However, because no incineration facilities are currently permitted to
receive and destroy dioxin and furan containing material, incineration cannot be
implemented at this time, nor can a time frame for this alternative be assessed.
Ground water would be treated as described for Alternative 2. The indirect, capital,
operating and maintenance costs associated with this alternative are presented in Table 3.
Due to the uncertainty associated with the ground-water remediation time frame, the
present worth of this alternative has been estimated based on both a 5-year and 10-year
ground-water remediation time frame at $18 million and $19 million, respectively.
4.3.5. Alternative 4a . On.Site Soil Treatment by DechloriDation and Ground-Water
Treatment by Air Stripping and GAC
Contaminated soil in Burial Sites 4-A and 4-E would be excavated as described under
Alternative 2 and treated on site using the Alkaline Polyethlene Glycol (APEG)
dechlorination treatment technology. Water purification tablets from Burial Site 4-D
would be excavated and transported off site for placement in a RCRA industrial landfill,
as described under Alternative 3a. The treated soil would be returned to the excavation.
Residues from the dechlorination unit would be required to comply with land disposal
restrictions (40 CFR 268) for FOOl through Foo5 listed wastes, dioxins, and furans prior to
placement in the excavation. The treated residue may be disposed of on site after passing
the TCLP treatment standards for FOOl through F005 listed wastes and dioxins and
delisting as a hazardous waste. The excavations would be backfilled with clean fill if
necessary, topsoiled and revegetated. This remedial action woiud be completed within two
to three years after the ROD is signed.
Ground' water would be treated as described for Alternative 2. The indirect, capital, .
operating. and maintenance costs associated with this alternative are presented in Table 3.
Due to the uncertainty associated with the ground-water remediation time frame, the
present worth value of this alternative has been assessed based on a 5-year and 10.year
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ground-water remediation time frame. The present worth has been estimated at $6.8
million and $7.6 million, respectively.
4.3.6. Alternative 4b - On-Site Soil Treatment by Incineration and Ground-Water
TreshnPnt by Air Stripping and GAC
Contaminated soil in Burial Sites 4-A and 4-E would be excavated and treated in an on site
incinerator prior to replacement in the excavation. This unit would be mobilized, operated,
and closed in accordance with the requirements of 40 CFR Part 264, Subpart 0 which is
considered relevant and appropriate. Subject to satisfactory treatability study results,
incineration would comply with ARARs for soil treatment. Residues from inciner~tion
would be required to comply with land disposal restrictions (40 CFR 268). The treated
residue may be disposed of on site after passing the TCLP treatment standards and
delisting as a hazardous waste. The incinerator must comply with the technical
requirements of the State of Utah clean air regulations (UAC Rule 446-12) and the 99.9999
percent destruction and removal efficiency requirements of RCRA (40 CFR Part 268).
However, as no mobile incineration facilities have been permitted for dioxin and furan
destruction, this alternative cannot be implemented, nor can a time frame be assessed.
The water purification tablets from Burial Site 4-D would be excavated and transported to
an off site RCRA industrial landfill as described under Alternative 3a.
Ground water would be treated as described under Alternative 2. The indirect, capital,
operating and maintenance costs associated with this alternative are presented in Table 3.
Due to the uncertainty associated with the ground-water remediation time frame, the
present worth value of this alternative has been assessed based on a 5-year and 10-year
ground-water remediation time frame. The present worth has been estimated at $7.0
million and $7.8 million respectively.
4.3."1. Altemative 6 - Conmin_t of ContA'ft'IinRtedSoil and GrouDd-Water Treatmen~
by UV/Ozone
Contaminated soil in Burial Sites 4-A and 4-E, and water purification tablets from Burial
Site 4-D, would be excavated and placed in an on-site landfill as described for
Alternative 2. Compliance with ARARs for soils are diseussed in Alternative 2. This
remedial action would be completed within 15 to 24 months after the ROD is signed.
Ground water would be extracted as described under Alternative 2 and pumped to an on-site
UV/ozone treatment facility. Treated ground water would be reinjected around the
perimeter of the contaminant plume using injection wens or infiltration galleries. Any
sludge generated by the UV/Ozone process would be treated in a similar manner ~ that
described for waste from the ground-water treatment process under Alternative 2. The
advantage of UV/Ozone technology over air stripping and GAC treatment is. that the
contaminants would be destroyed rather than transferred to another medium and there.
would be no air emission. that would trigger ARARs. However, the wide range of
contaminants present in the ground water may make technical implementation of this
. technology difficult and the presence of oil and grease in the ground water at OU 4 may
minimize. the efficiency of the process. In addition, it would be necessary to carry out a
treatability.study to determine destruction efficiency of the UV/Ozone system. Alternative
5 would comply with ground-water ARARa, assuming MCLs could be achieved and
maintained. The extraction and reinjection system would comply with the Federal
underground injection regulations (40 CFR Parts 144-147) and the State well drilling
. standards of UAC Rule 625-4.
Ground-water remediation would eventual1y reduce the health-based risks to one in ten
thousand with a target level of one in 1)ne miUion and achieve MCLs that ate considered. to
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be ARARs. The time frame required for compiiance with ground-water cleanup criteria is
estimated to be a minimum of five years, assuming treatment of a' minimum of five pore
volumes (approximately 330 million gallons) wHl be necessary to attain ARARs.
However, the ability of the pump and treat approach to achieve very low residuals (less than
2 J.,Lg/L for vinyl chloride) in ground water may be limited.
The indirect, capital, operating and maintenance costs associated with this alternative are
presented in Table 3. It should be noted that pretreatment of ground water may be required,
which could add significant costs to this alternative. However, without a treatability study
and a pilot scale plant those costs cannot be adequately determined. Due to. the uncertainty
associated with the ground-water remediation time frame, the present worth of this
alternative has been estimated based on a 5-year and 10-year ground-water remediation
time frame at $3.1 million and $3.9 million, respectively.
4.3.8. Alternative 6a - Off-Site Soil Disposal and Ground-Water Trt>.tmP.nt by UV/Ozone
Contaminated soil in Burial Sites 4-A and 4-E would be excavated and transported to an
off-site facility for placement in a RCRA hazardous waste landfill and water purification
tablets from Burial Site 4-D would be excavated and transported to a RCRA industrial
landfill for disposal, as described in Alternative 3a. Ground water would be extracted and
pumped, to an on-site UV/ozone treatment facility as described in Alternative 5.
Compliance with ARARs for soil is discussed in Alternative 3a. Compliance with ground-
water ARARs is discussed in Alternative 5.
The indirect, capital, operating and maintenance costs associated with this alternative are
presented in Table 3. Due to the uncertainty associated with the ground-water remediation
time frame, the present worth of this alternative has been estimated based on a 5-year and
10-year ground-water remediation time frame at $3.9 million and $4.6 million,
respective)y.
4.3.9. Alternative 6b - Off-Site Soil Incineration and Ground-Water Treatment by
UV/Ozone
Contaminated soil in Burial Sites 4-A and 4-E would be excavated and transported to an
off-site facility for incineration, as described in Alternative 3b. Water purification tablets
from Burial Site 4-D would be excavated and transported to an off-site facility for disposal
in a RCRA industrial landfill, as described in Alternative 3a. Ground water would be
extracted and pumped to an on-site UV/ozonetreatment facility, as described.in
Alternative 5. Compliance with ARARs for soil was discussed in Alternative 3b and for
ground water it was discussed in Alternative 5.
The indirect, capital, operating and maintenance costs associated with this alternative are
presented in Table 3. Due to the uncertainty associated with the ground-water remediation
time frame, the present worth of this alternative has been estimated based on a 5 year and
10-year ground-water remediation time frame at $18 million and $19 million,
respectively.
4.3.1~. Altemative 7a - On-Site Son Treatment by DechloriDation and Ground-Water
Treatment by UVIOzone
Contaminated soil in Burial Sites 4-A and 4-E would be excavated and treated on site using
dechlorination, as described in Alternative 4a. The treated soil would be returned to the
excavation. Ground water would be pumped to an on-site UV/ozone treatment facility and
the treated ground water would be reinjected around the perimeter of the contaminant
plume using injection wells or infiltration galleries, as described in Alternative 5. The
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compliance of the dechlorination treatment technology with ~s is discussed in
Alternative 4a. Compliance of the UV/Ozone gTound-water treatment system with ARARs
is discussed in Alternative 5.
The indirect, capital, operating and maintenance costs associated with this alternative are
presented in Table 3. Due to the uncertainty associated with the ground-water remediation
time frame. the preserit worth of this alternative has been estimated based on a 5-year and
lO-year gTound-water remediation time frame at $6.9 million and $7.6 million,
respectively.
4.3.11. Alternative 7b - On-Site Soil Treatment by Incineration and Ground-Water
TreatmeDt by UV/Ozone .
Contaminated soil in Burial Sites 4-A and 4-E would be excavated and treated in an on site
incinerator prior to replacement in the excavation, as described iri Alternative 4b. The
treated soil would be returned to the excavation. The water purification tablets from Burial
Site 4-D would be excavated and transported to an off site RCRA industrial landfill, as
described 1.1nder Alternative 3a. However, as no mobile incineration facilities have been
pennitted for dioxin and furan destniction, this alternative cannot be implemented, nor
can a time frame be assessed.
Ground water would be pumped to an on-site UV/ozone treatment facility and the treated
gTound water would be reinjected around the perimeter of the contaminant plume using
injection wells or infiltration galleries, as described in Alternative 5. Compliance with
gTound-water ARARs will be achieved and is also discussed in Alternative 5.
The indirect, capital, operating and maintenance costs associated with this alternative are
presented in Table 3. Due.to the uncertainty associated.with the ground-water remediation
time frame, the present worth of this alternative has been estimated. based on a 5-year and
lO-year gTound-water remediation time frame at $7.1 million and $7.8 million
respectively. .
4.4 COMPARATIVE ANALYSIS OF REMEDIATION ALTERNATIVES
During the detailed analysis for OU 4, each alternative was assessed against the nine
evaluation criteria defined under CERCLA. These .criteria have been developed to address
the technical and policy considerations that have proven important for selecting among
remedial alternatives and serve as the basis for the detailed analysis and the subsequent
selectio.n of an appropriate remedial action. In assessing alternatives, all must meet
criteria numbers 1 and 2, which are the threshold criteria. Those alternatives satisfying
the threshold criteria are compared using the five balancing criteria. The final two
modifying criteria can change the preferred alternative selected as Ii result of applying the
balancing criteria. The evaluation criteria are:
,",1"P!IIhnld Criteria
1.
Overall Protection of Human Health aDd the Environment - The
assessment against this criterion describes how the alternative, as a 'whole,
achieves and maintains protection of human health and the environment.
2.
Compliance with ARABs - The assessment against this criterion describes
how the alternative complies with ARARs or, if a waiver is required, how it
is justified. The assessment also addresses other information from
advisories, criteria, and guidance documents that the parties have agreed is
"to be considered."
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R:llRncinv Criteria
3.
Long-term Effectiveness and Permanence - The assessment of
alternatives against this criterion evaluates the long-term effectiveness of
each alternative in protecting human health and the environment after the
response objectives have been met.
4.
Reduction of Mobility, Toxicity, and Volume Through Treatment - The
assessment against this criterion evaluates the anticipated performance of
the specific treatment technologies an alternative may employ.
5.
Short-term Effectiveness - The assessment against this criterion examines
the effectiveness of alternatives in protecting. human health and the
environment during the construction and implementation of a remedy and
until the response objectives have been met.
6. .
Implementability - The assessment against this criterion evaluates the
technical and administrative feasibility of the alternatives and the
availability of the goods and services needed to implement them.
7.
Cost - The assessment against this criterion evaluates the capital, indirect,
and operation and maintenance costs of each alternative. Cost can only be
a deciding factor for alternatives equally protective of human health and
the environment.
Modifvin~ CritP.ria
8.
State Accep~ce - This criterion reflects the State's preferences among or
concerns. about alternatives. .
9.
Community Accepiance - This criterion reflects the community's
preferences among or concerns about alternatives.
The results of the assessment of alternatives against the nine criteria were arrayed in
Table 3 to compare the alternatives and identify the key tradeoffs among them. A
comparative analysis of alternatives was then conducted to evaluate the alternatives with
respect to their relative performance according to the threshold and balancing criteria.
The objective of the comparison is to assess the relative advantages and disadvantages
among the alternatives. The results of this comparison are presented below.
Overall Protection ofBuman Health and the Environment. Assuming that present land
practices at DDOU remain unchanged, all the remedial alternatives presented in this
detailed analysis would be equally protective of human health and the environment
because there are currently no exposure pathways to contaminated soil or ground water at
au 4. . Under all remedial alternatives and present land use practices, the risk to human
health due to exposure to soil contaminated with PCBs, dioxins, and furans is less than
one in one million. Under Alternative 1, the no action altemative, lack of action may
result in off-site migration of contaminated ground water. While there is cur:rently no
domestic or on-Depot use of the shallow ground-water aquifer in the vicinity of au 4, the
future risk to the public would increase under these conditions. All other alternatives
would prevent off-Depot migration of the ground water and would reduce risks associated
with potential future use of on-Depot shallow ground water. Therefore, Alternative 1 fails
to meet the criterion, and Alternatives 2 through 7 comply with it.
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Compliance with.ARARs. Alterna6ves 2 through 7 would comply with ARARs relating to
soil treatment and disposal. However, failure to remove the source under Alternative 1
would not comply with UAC Rule 450-101. Alternatives that use landfilling of dioxin and
furan contaminated soils (Alternatives 2, 3a, 5, and 6a) would comply with ARARs if soils
pass the TCLP treatment standards for dioxins and furans and those for FOOl through F005
listed wastes. If soils fail the TCLP, they would be treated to achieve compliance with
ARARs. The no action alternative (Alternative 1) would fail to meet ARARs for ground
water. All other alternatives would result in compliance with ARARs for ground water,
given the limitations of pump and treat technology. The time frame for compliance with
ground-water ARARs may be greater than 10 years and would depend on actual response of
the aquifer during remediation. If the treatment method fails to achieve or maintain
MCLs in the ground water, the treatment method and cleanup levels should be reviewed
and revised if necessary. Alternatives 4a, 4b, 7a, 7b and the incineration option in
Alternatives 3b and 6b would provide the greatest degree of compliance due to the complete
removal and destruction of the source and remediation of the aquifer that would be
achieved.
Long-Term Effectiveness and Permanence. The no action alternative would provide the
least compliance with this criterion. The permanence of landfilling of contaminated soils
under Alternatives 2, 3a, 5, and 6a would rate lower than the complete destruction of
contaminants achieved through treatment in Alternatives 4a, 4b, 7a, and 7b and the
incineration option in Alternatives 3b and 6b. Therefore, Alternatives 48, 4b, 7a, and Th
and the incineration option in Alternatives 3b and 6b would rate highest under this
criterion. .
Reduction in Mobility, Toxicity, and Volume Through Treatment. Alternative 1 rates
lowest against this criterion because no action would be taken to remediate contaminated
soil and ground water. The lack of treatment to reduce toxicity, mobility, or volume under
the landfilling options in Alternatives 2, 3a, 5, and 6a would result in a lower rating than
alternatives that use treatment. Alternatives 4a, 4b, 7a, and Th, and the incineration option
in Alternatives 3b and 6b, therefore rate higher due to the complete destruction of
contaminants in the soil that. would occur under those alternatives. However, treatability
studies would be required to confirm the efficiency of the dechlorination, on-site
incineration, and UV/Ozone technologies.
Short-Term Effectiveness. With the excepti9n of the no action alternative, all of the
alternatives compare equally under this criterion. As no action would be taken under
Alternative 1, there are no short term risks. All other alternatives involve similar risks
created by the methods used to extract and treat the contaminated soil and ground water.
Therefore Alternatives 2 through 7 rate lower than Alternative 1 under this criterion.
Implementability. Technically, the no action alternative would be the easiest alternative
to implement but would not be implementable adIDinistratively due to the need to meet
ground-water MCLs. On-site landfi11ing of soils and debris under Alternatives 2 and 5
would be difficult to implement due to the long-term administrative requirements
associated with such a facility. The incineration alternatives for soil destruction under
Alternatives 3b; 4b, 6b, and 7b would require compliance with technical permitting
requirements of RCRA and State and Federal air emission regulations. However, no
incineration facilities have been permitted for dioxin and furan destruction in the United
States, thereby preventing the implementation of any of the incineration alternatives at
this time. Dechlorination would require a treatability study to confirm the ability of this
technology to treat PCB, dioxin, and fuTan-contaminated soils and wastes from OU 4.
UV/Ozone treatment of ground water under Alternatives 5, 6a, 6b, 7a, and 7b may be the
easiest to implement administratively due to the lack of treatment by-products and air
. emissions, when compared to air stripping and GAC treatment. However, as an
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innovative technology, technical implementability would have to be proven by a
treatability study and the presence of oil and grease in the OU 4 ground water may
minimize the efficiency of the oxidation process. Assuming treatability studies are
successful, Alternatives 3b and 6b rate lowest for this criterion, followed by Alternatives 2,
4b, 5, and 7b. Landfill disposal under Alternative 6a is rated sJightly higher, while
landfill disposal under Alternative 3a rates highest with respect to implementability.
Cost. The indirect, capital, operation and maintenance costs, and net present worths of
remediation alternatives are presented in Table 3. The no action alternative (Alternative
1) h&~ the lowest cost of all the alternatives considered, with a present worth of $287,000 for a
20-year monitoring period. Alternatives 2 and 5 (on-site soil landfi11ing with air
strippinw'GAC or UV/Ozone, respectively) both have lO-year present worths of about $3.9
miJlion. The dechlorination soil treatment options in Alternatives 4a and 7a have a 10
year present worth of about $7.6 million, followed by the on-site soil incineration treatment
options of Alternatives 4b and 7b at about $7.8 million. Alternatives 3a and 6a, both of
which employ off-site soil landfiUing as treatment, have 10-year present worths of $4.5
million and $4.6 miUion, respectively. The off-site incineration options of Alternatives 3b
and 6b have 10-year present worth of $19 million each.
State Acceptance. The State has been involved in each step of the RIlFS process and the
presentation of a preferred alternative in the Proposed Plan. Therefore, this criteria has
been addressed in the development of a remedy for OU 4. The State is supportive of the
selected remedy but had a preference for off-site incineration of all soil and debris.
However, as stated' under the description of alternatives that employ incineration, this is
not currently implementable. .
Community Acceptance. Community. acceptance is implicitly analyzed for the selected
remedy in the Responsiveness Summary at the end of this document. All comments
received during the public comment period have been addressed and the alternatives
altered, if necessary. Only one comment was received from the public that indicated a
preference for on-site treatment rather than off-site disposal. Therefore, public concerns
regarding the selection of a remedy for OU 4 have been addressed.
5.0 SELECTED REMEDY
The selected remedy for DDOU Operable Unit 4 is Alternative 3a, off-site landfill disposal
of soil and debris and on-site ground-water treatment using air stripping and GAC, if
necessary. This remedy was presented as the preferred alternative in the Proposed Plan
for OU 4. A detailed description of the selected alternative, including the remediation
goals, cleanup levels, and the costs associated with each component of the remedy is
presented in the following discussion.
5.1 DESCRIPTION OF THE SELECTED REMEDY
Under this alternative, contaminated soil in Burial Sites 4-A and 4-E will be excavated
and placed in an off-site ReRA hazardous waste landfill. Water purification tablets from
Burial" Site 4-D win be placed in an off-site RCRA industrial landfill. ....A"~
operator will remove, treat, .and .dispose ~f,.methy1'bromi1le. ey1maen~"~"!81Iie
encountereti. During excavation of the soil and debris, TCLP tests will be performed
periodicaHy (with a frequency to be determined during the remedial design) to confirm the
characteristics of the waste and itS suitability for .land disposal. If a soil sample fails the
TCLP criteria for FOOl through FOOS listed wastes, the soil volume represented by this
sample will be treated by the receiving facility using granulated activated carbon or other
stabilization/fixation methods to achieve compliance. If treatment is unsuccessful in
. achieving treatment standards for land disposal of dioxins, the failing material will be
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transported to a commercial incineration facility for thermal treatment. While no
facilities are cutTently permitted for dioxin destruction, storage of material at the facility
can be undertaken until permitting is completed. Based on TCLP analyses carned out on
soils from Burial Sites 4.A and 4-E, it is unlikely that incineration wi]} be necessary.
Ground water will be remediated using a we]} extraction, treatment, and reinjection
system. Ground water will enter an air stripper tower treatment system to remove vinyl
chloride, cis-1,2-DCE and other vacs present in ground water at au 4. The air stripper
. will reduce vinyl chloride concentrations to less than 2 IJ.g/L and cis-1,2-DCE
concentrations to a practicably attainable level that is less than the MCL of 70 1J,g/L. If PCB
concentrations in the effluent from the air stripper exceed the MCL of 0.5 JJ,g!L, or if dioxin
and furan isomers exceed the proposed MCL of 3 x 10-5 ~ for total equivalent TCDD, a
GAC treatment unit wi]} be added to reduce contaminant concentrations to these levels.
Air emissions from the air stripper tower wi]} be monitored to ensure compliance with Utah
air quality regulations of 1.5 tons of total vacs per year and the NESHAPs requirements
for vinyl chloride of 10 parts per million. If emission levels threaten or exceed these
criteria, air emission controls such as GAC or some other effective technology wi]} be
employed. Wastes from the ground-water treatment process, including silt collected by
gravity separation in the air stripper or pretreatment units, will be transported off-site for
incineration or land disposal, depending on how the wastes are classified under RCRA as
described in Section 4.3.2. Treated ground water will be reinjected into the shallow
aquifer using injection wells or infiltration galleries.
The ground-water treatment system wi]} be operated either continuously, by pulsing the
system, turning off individual wells, or pumping alternate wells to vary ground-water
flow patterns. Such measures wi]} be taken to reduce the remediation time frame where
practicable, while ensuring compliance with ground-water and air emissions ARARs.
The ground-water treatment system will be operated until the remediation goals for
ground water outlined below have been met and maintained for one year in all compliance
monitoring wells. When contaminants have been maintained below MCLs for one year,
the treatment system will be shut down and compliance monitoring will continue until the
next scheduled statutory five year review. If remediation goals are exceeded during this
time in any compliance monitoring well, ground-water treatment will recommence and
this procedure wi]} be .repeated. If compliance is maintained until the next scheduled
statutory review the remedy will be considered complete. The Performance and
Compliance Monitoring Plan is presented in Appendix B of this document.
During constTU:ction of the extraction and reinjection wells, well tests will be conducted on
each we]} to determine the yield that can be expected during production. The number,
spacing, and pumping rate of wells will be adjusted according to the results of these tests.
The process components of this alternative and pertinent information and assumptions on
sizing, concentrations, flow rates, etc., are presented in Table 4. It should be noted that
some changes may be made to this remedy as a result of the remedial design and
construction process.
5.1.1. Remediation Goals
The point .of compliance for soil wi]} be defined by the cleanup criteria described below.
The first of these criteria consists of removing all debris and visually contamInated soil
from Burial Sites 4-A and 4-E, and removal of water purification tablets from Burial Site
4-D. Visually contaminated soil is defined as any soil containing manufactured or
processed material, plant or animal matter, or unnatural discoloration. Samples will
then be collected from the soil in the walls and bottom of the excavation and analyzed for
vacs, PCBs, metals, dioxins, and furans. These sample results will be used to confirm
that the soils remaining in the excavation:
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TABLE 4
ALTERNATIVE 3a - OFF.SITE LANDFILL DISPOSAL OF SOIl. AND
GROUND-WATER TREATMENT BY AIR STRIPPING/GAC
, Ground Water
SoU
Exposure Control
EqJo&ure Control
Eliminate exposure pathway. through remediation
Eliminate exposure pathways by removing backfilled soil and debris
Extraction. Ealnlctlon Well.
Euractlon - Eacavation
System of 30 weUs, each 30-feet deep, 4-inch diameter
Individual wen Oow raw .. 6 gpm, oil/water separators where necessary
. Excavate approximately 4,500 cubic yards of contaminated soil
Transport soil and debris from Burial Site 4-A and 4-E off-site to RcnA
hazardous waste landfill
Transport water purification tablets off site to RCRA indushiallandf'ill
Backfill excavation with clean soil
Regrade and revegetate excavation site
1reahnent.AJrSbipp~
,
~
...:I
,
Flow rate =160 gpm
Surge Tank.. 6,000 ganons
InOuent water temperature - 60" F
InOuent vinyl chloride concentration - <2,000 J1g/L
~muent vinyl chloride concentration - < 2 J1g/L
InOuent cis-l,2-DCE - 20,000 f.Ii/L
Emuent ci.-l,2-DCE S 70 f.Ii/L
Vapor pha.e control. .. None (GAC only if emission. exceed Utah Clean Air
Regulations or the 40 CFR 61 vinyl chloride concentration of 10 ppm)
Treatment
RCRA permitted landfill (if necessary for FOOl through F005 listed wastes)
Incinerator (if necessary for dioxins and furans)
Dispo8aI
DIsposaI- Re~tlon Into SbaUow Aquller
RCRA hazardous waste landfill for soils and debris from Burial Sites 4-A
and 4-E
RGRA industrial waste landfill for water purification tablet boules
System of 30 i.uection wens, each 10-feet deep, 4-inch diameter
Individual wen now rate. I! 6 gpm
SoU DIsposaIII'reahnent Costs
Ground-Water Treatment Coetl (Include8 AIr Stripping and
Carbon Ad8orpdon) .
Assumes disposal of all soil and debris in a RCRA hazardous waste
landfill without treatment
Indirect .. $190,000 . Capital .. $867,000
Annual O&M .. $229,000
Indirect.. $150,000
Capital.. $1,328,000
Annual O&M .. $0
Indirect costs include administration, engineering, and design
Indirect costs include soil analysis necessary for landfill disposal
O&M coats include monitoring program cost.
Capital costs include excavation/transport/disposal
Total Costs:
Indirec& - tMO,ooo
Capital .. $2,195,000
Annual O&M - $229,000
Present Worlh Cost .. $1,600,000
(10 yn + 2 yn post-remediation monitoring)
-------
1.
Do not contain more than 25 mg/kg of PCBs as recommended in EPA
Directive 9355.4-0 IFS.
2.
Do not contain dioxin and furan concentrations of more than I J.1gIkg total
equivalent TCDD as recommended by the Dioxin Advisory Group.
3.
Do not contain other contaminants that would present an unacceptable
future health risk. Excavation will continue until a total carcinogenic
health risk of less than one ~.1 ten thousand is achieved in the soils
remaining in the excavation. In addition, a target cleanup level of one in
one miHion has been adopted for au 4 and will be achieved wherever
practicable. Similarly, excavation win continue until the hazard index for
noncarcinogenic contaminants remaining in the soil is less than one.
Contaminant concentrations associated with these risk levels are presented
in Table A-2 in Appendix A, assuming a future resident exposure scenario.
Risk based cleanup levels are only defined (or those contaminants that do
not have specific, defined cleanup levels.
Health based cleanup criteria have been included as remediation goals to ensure that the
remedy complies with the NCP recommendation that an excess health based risk of
between one in ten thousand and one in one million should be achieved by the remedy, with
a risk of one in one million as the goal of the remediation. Confinnation samples win be
taken from soils remaining in the excavation to verify compliance with the cleanup
criteria. Excavated soil and debris will be periodically tested using appropriate analyses
including the Toxic Characteristics Leaching Procedure (TCLP). This test will ensure
proper characterization of the material so that the landfill receiving it can detennine if
treatment will be necessary prior to landfill disposal and confirm that the waste has been
correctly characterized. The existing frequency will be specified in the remedial design.
Ground water wi11 be treated until contaminant concentrations are below their MCLs.
Contaminants of concern for ground-water remediation and their associated MCLs are
listed in Table A-I in Appendix A The point of compliance for ground-water cleanup is
defined by the area within the 2 J,IgIL contour for vinyl chloride.
A Performance and Compliance Monitoring Plan for soil and ground water remediation
at au 4 is presented in Appendix B. This plan summarizes the remediation goals, areas of
attainment, restoration time frame, and the performance standards for soil and ground-
water remediation.
5.1.2. Costs
The costs associated with remediation of au 4 using Alternative 3a are listed in Table 4.
The total capital cost of the project is estimated at approximately $2.2 million. This
includes costs of installing a ground-water extraction and injection system, storage tank,
an air. stripping system equipped with GAC if necessary, ground-water monitoring,
excavation, soil disposal at.a ReRA hazardous waste landfill, and reclamation of the site.
Indirect costs for administration, engineering, and design. seTVices were estimated to be
approximately $340,000, while annual operation and maintenance costs are estimated at
$230,000. The present worth cost of the project, using a five percent discount value, is
estimated at $4.5 million, based on a 12 year duration of treatment and monitoring.
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5.2 STATUTORY DETERMINATIONS
The selected Temedy fOT DDOU OpeTable Unit 4 meets the statutory requiTements of
Section 121 of CERCLA as amended by SARA. These statutory requiTements include
pTotection of human health and the environment, compliance with ARARs, cost
effectiveness, utilization of permanent solutions and alternative treatment technologies to
the maximum extent practicable, and preference fOT treatment as a principal element. The
manner in which the selected remedy for DDOU OU 4 meets each of these requirements is
presented in the following discussion.
5.2.1. Protection of Human Health and the Environment
The selected remedy for DDOU OU 4 protects human health and the environment through
the following engineering controls:
.
Excavation and removal of all backfilled soil and debris in Burial Sites.
4-A and 4-E to c9mply with the cleanup criteria defined in Section 5.1.1. and
Temoval of the water purification tablet bottles in Burial Site 4-D.
.
Extraction and treatment of all gTound water until contaminant
concentrations are below their MCLs, and total excess cancer risks are less
than one in ten thousand with a target of one in one million.
Removal of the soil and debris in Burial Sites 4-A and 4-E will eliminate the source of
organic contamination in the ground water and remove the potential for exposure to these
contaminants in soil. Removal of the water purification tablet bottles in Burial Site 4-D
will remove a potential future exposure pathway to the contents of these bottles. Treatment
of contaminated ground water at au 4 to a level below the MCLs will result in a reduction
in the cancer risk to potential future ground-water users by approximately two orders of
magnitude. The selected remedy for soil and ground water at OU 4 will not pose an
unacceptable short-term risk to human health, the environment, or endangered species
and their habitats, nor will the site present any unacceptable risks afl;er completion of the
remedy. The selected remedy will al80 minimize cross-media impacts through the use of
air emission controls if necessary. This latter point will be achieved by ensuring
compliance with Utah air quality regulations and Federal requirements for vinyl chloride
defined by NESHAPS.
5.2.2. Compliance with Applicable or Re1ewnt and Appropriate Requirements
Section 121(d)(1) of CERCLA as amended by SARA, requires that remedial actions must
attain a degree of cleanup which assures protection of human health and the environment.
In addition,remedial actions that leave any hazardous substances, pollutants, or
. contaminants on site must, upon completion, meet 8, level or standard which at least
attains legally applicable or relevant and appropriate standards, requirements,
limitations, or criteria that are "applicable or relevant and appropriate requirements"
(ARARs) under the circumstances of the release. ARARs include Federal standards,
requirements, c1jteria, and limitations and any promulgated standards, requirements,
criteria or .limitations under 'State environmental or facility siting regulations that are
-more stringent than Federal standards. .
"Applicable" requirements are those cleanup standards, standaTds of control, and other
substantive environmental protection requirements, criteria, or limitations promulgated
under Federal or State law that specifically address a hazardous substance, pollutant or
contaminant, remedial action, location, or other circumstance at a remedial action site.
"Relevant and appropriate" requirements are cleanup standards, standards of control,
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and other substantive environmental protection requirements, criteria, or limitations
promulgated under Federal or State law that, while not "applicable" to a hazardous
substance, pollutant or contaminant, remedial action, location, or other circumstance at a
remedial action site, address problems or situations sufficiently similar to those
encountered at the site that their use is well-suited to the particular site.
In determining which requirements are relevant and appropriate, the criteria differ
depending on the type of requirement under consideration, i.e., chemical-specific,
location-specific, or action-specific. According to the NCP, chemical-specific ARARs are
usually health or risk-based numerical values which establish the acceptable amount or
concentration of a chemical that may remain in, or be discharged to, the ambient
environment. Location-specific ARARs generally are restrictions placed upon the
concentration of hazardous substances or the conduct of activities solely because they are in
special locations. Some examples of special locations include floodplains, wetlands,
historic places; and sensitive ecosystems or habitats. Action-specific ARARs are usually
technology- or activity-based requirements or limitations on actions taken with respect to
hazardous wastes, or requirements to conduct certain actions to address particular
circumstances at a site. Remedial alternatives which involved, for example, closure or
discharge of dredged or fin material may be subject to ARARs of RCRA and the Clean
Water Act.
The remedial action proposed, the hazardous substances present at the site, the physical
characteristics of the site, and the potential receptor population, were an considered when
determining which requirements are applicable or relevant and appropriate to the selected
remedy for au 4. Federal and State laws, standards, requirements, criteria, and
limitations were reviewed for possible applicability to au 4. The only State regulations
identified that required more stringent requirements than equivalent Federal regulations
were the source control regulations in Utah Administrative Code WAC) Rule 450-101, and
the spill reporting requirements in UAC Rule 450-9.
Through careful t:eview of an applicable or relevant and appropriate public health and
environmental requirements of Federal or State laws, it has been determined that the
remedy selected for OU 4 will meet these ARARs. Therefore, no SARA Section 121(d)(4)
waiver will be necessary. A brief discussion of how the selected remedy for OU 4 satisfies
the principal ARARs associated with the site is presented below.
Chemical-Specific Requirements. Chemical-specific ARARs set health- or risk-based
concentration limits in various environmental media. Ground-water quality ARARs for
au 4 are based on the Safe Drinking Water Act maximum contaminant level (MCL), the
maximum permissible level of a contaminant in water that is delivered to any user of a
public water system. MCLs are generally relevant and appropriate as cleanup standards
for contaminated ground water that is or may be used for drinking. Other applicable
requirements include RCRA land disposal restrictions, the Solid Waste Disposal Act, the
Clean Air Act, the Occupational Safety and Health Administration (OSHA) regulations,
and the Department of Transportation (DOT) hazardous material transportation
regulations. The State of Utah public drinking water regulations are also relevant and
appropriate to the OU 4 selected remedy. In addition, the Utah ground-water quality
protection regulations are applicable to the site. Potential Federal and State chemical-
specific ARARs are presented in Tables C-l and C-2 of Appendix C. .
Location-Specific Requirements. Location-specific ARARs set restrictions on
remediation activities, depending on the location of a site or its immediate environs. The
only location-specific ARAR associated with the selected remedy for au 4 is the EPA
ground-water protection strategy that establishes a ground-water classification system for
protecting ground water based on its value to society, use, and vulnerability. This strategy
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contributes to application of the National Primary Drinking Water Standards as ARARs
for the selected remedy. As OU 4 is not located in a wetlands area or floodplain, is not a
historic place, and the remedy wil1 not affect any historic place, endangered species, or
habitats, regulations pertaining to these concerns are not ARARs.
Action-Specific Requirements. Performance, design, or other action-specific
requirements set controls or restrictions on certain kinds of remedial activities related to
management of hazardous substances, pollutants, and contaminants. Federal action-
specific ARARs that are relevant to the remediation activities at OU 4 include Federal
UndergTound Injection Control Regulations, RCRA Land Disposal and Closure
Regulations, the Solid Waste Disposal Act, and the Occupational Safety and Health Act
(OSHA). State. requirements include the Utah State Engineer's regulations for well
construction and pumping activities, the Utah Corrective Action Cleanup Standards Policy
for cleanup levels, and the Utah Air Quality Regulations. Potential Federal and State
action-specific ARARs are presented in Tables C-3 and C-4 of Appendix C. .
To Be Considered Requirements. In implementing the selected remedy for OU 4, DDOU
has &gTeed to consider requirements that are not legally binding. The only requirements
to be considered (TBC) for the selected remedy at DDOU OU 4 were the adoption of the
recommendations of the Dioxin Disposal Adversary Group regarding pentachlorophenol
waste and dioxin and furan contamination and the recommended cleanup level for PCBs
on industrial sites presented in EPA Directive 9355.4-01FS. These TBCs are included in
the Federal chemical-specific ARARs presented in Table C-l.
5.3 COSTEFFECTIVENESS
Overall cost-effectiveness can be defined as the reduction in threat to human health and the
environment per dollars expended on a remedy. The selected remedy for DDOU OU 4 is
the most cost-effective alternative because it provides the maximum effectiveness
proportional to cost of any of the alternatives analyzed. The selected remedy is an order of
magnitude less in costs than the off-site incineration alternative, and provides a gTeater
degree of protectiveness of human health and the environment when compared to the on-
site remediation alternatives. The selected remedy will also be protective in the long term
because it removes the source of ground-water contaminants from the site, and allows
clean closure of the site in a cost effective manner.
5.4 UTILIZATION OF PERMANENT SOLUTIONS
This section briefly describes the rationale for the selected remedy and explains how the
remedy provides the best balance of tradeoffs among all the alternatives with respect to the
five balancing criteria described in Section 4.4.
EPA, the State of Utah, and DDOU have determined that the selected remedy represents the
maximum extent to which permanent solutions. and treatment technologies can be utilized
in a cost effective manner for the final source control and ground-water remediation at
OU 4. While the selected alternative does not provide the highest degree of protectiveness
afforded by alternative. that use incineration of soils, it will significantly reduce the
inherent. hazards posed by contaminated soils and their potential to act as a continuing
source of ground-water contamination. In addition, at this time there are no incineration
facilities in the United States that are permitted to receive and incinerate dioxin
contaminated material. This limitation prevents implementation of incineration
alternatives for OU 4. Therefore, Alternatives 3b, 4b, 6b, and 7b could not be implemented.
The greatest degree of reduction in mobility, toxicity, and volume would be achieved by
alternatives that used dechlorination or incineration of soils. However, because the soils
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from Burial Sites 4-A and 4-E and the water purification tablets can be land disposed in
compliance with RCRA, mobility wi11 be control1ed but toxicity .and volume wi1l be
unaffected under the selected alternative. Because the selected remedy does not destroy the
contaminants in soil or ground water, it does not rate as high against this criteria as
alternatives that use dechlorination for soil treatment or UV/Ozone for ground-water
treatment. However, the presence of oil and grease in OU 4 ground water may minimize
the effectiveness of UV/Ozone to reduce mobility, toxicity, and volume. .
The short term effect associated with soil remediation under each alternative is the
potential exposure of workers and t.~arby residents to contaminated dust. This can be
controlled by the use of appropriate protective equipment and dust control measures. There
is also a short term exposure generated by alternatives that use air strippers and GAC for
ground-water treatment and incineration of soils. This exposure potential will be
controlled by compliance with State and Federal air emission regulations. Alternatives
that employ UV/Ozone would not have this short term exposure potential. Therefore, the
selected alternative is rated higher than alternatives that employ incineration but lower
than those that use UV/Ozone under this criterion.
Because the soils in Burial Sites 4-A and 4-E contain dioxins and furans, alternatives that
employ incineration of soils are impossible to implement, as described above. The
administrative and technical implementability of constructing, operating, and
maintaining an on-site RCRA hazardous waste landfil1 was considered less satisf~ctory
than using an existing commercial facility off site. Dechlorination is an innovative
technology that would require treatability testing to determine its effectiveness on the
range of contaminants found at OU 4, and the suitability of the treated soils for
replacement in the excavation on site. If treatability tests were not satisfactory, or treated
soils could not be backfilled on site, the alternative would not achieve any greater
reduction in mobility, toxicity, or ~olume, or long term effectiveness than the selected
alternative. Similarly, the air stripping and GAC treatment system for ground water in
the selected alternative are proven technologies that are technically implementable,
commercially available, and administratively implementable. The technical
implementability of the UV /Ozone technology would be subject tp the results of a treatability
study which makes this system less implementable than the air stripping and GAC system
used in the selected alternative.
The cost of alternatives that employed off-site incineration were significantly greater than
alternatives that employed on-site solutions or off-site landfilling. In addition,
alternatives that employed on-site or off-site landfiUing were less expensive than those
that employed on-site treatment. .
Of those alternatives that were carried through the detailed analysis, the selected remedy
provides the best balance of tradeoft's in terms of the balancing criteria listed above. The
major tradeoft"s that provide the basis for this selection decision are implementability, long
term effectiveness, and cost. The selected remedy can be implemented more quickly, with
less difficulty, and at less cost than the other treatment alternatives while providing the
same degree of protectiveness. . Therefore, Alternative 3a was selected as the most
appropriate solution forremediating the cO':!taminated soils and ground water at OU 4.
5.5 PREFERENCE FOR TREATMENT AS A PRINCIPAL ELEMENT
The selected remedy does not use treatment for remediating soils. The potential for
employing treatment as a principal element of source area remediation is limited by
administrative restrictions associated with the presence of dioxins in the contaminated
soils and debris, and the lack of a proven technology for treating the range of
contaminants encountered at OU 4. The selected remedy does however employ treatment
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as a principal element for remediation of contaminated ground water. Ground water will
be treated through an air stripping system that may include GAC for adsorption of organics
that cannot be removed by air stripping. .
5.6 DOCUMENTATION OF NO SIGNIFICANT CHANGES
The Proposed Plan for DDOU OU 4 was released for public comment in December 1991.
The Proposed Plan identified Alternative 3a, OfT-Site Landfill Disposal of Soil and
Ground-Water Treatment by Air Stripping/GAC, as the preferred alternative. All written
and verbal comments submitted during the comment period were reviewed. The
conclusion of this review was that no significant changes to the remedy, as identified in
the Proposed Plan, were nec;essary. .
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APPENDIX A
SOIL AND .GROUND-WATER
REMEDIATION CRITERIA
-------
APPENDIX A
son. AND GROUND-WATER REMEDIATION CRITERIA
This appendix describes the remediation criteria for soil and ground water at Operable
Unit 4 (CU 4). Criteria for ground-water contaminants must be met in each compliance
monitoring well. Confirmational soil samples will be collected after removing debris and
visibly contaminated soil from Burial Sites 4-A and 4-E. Results of these sample analyses
will be used to confirm that all material contaminated above the cleanup levels has been
removed from the excavation.
Ground.Water Remediation Criteria
Contaminants of concern for ground-water remediation for OU 4 include benzene, cis-I,2-
dichloroethene (cis-I,2-DCE), vinyl chloride, polychlorinated biphenyls (PCBs). and
TCDD. The remediation criteria for these compounds are their respective drinking water
maximum contaminant levels (MCLs) of 5, 70, 2, 0.5 and 0.00003 IJg/L.
Table A-I summarizes the cleanup criteria for each contaminant of concern in ground
water, the potential cancer risk and ha;ard quotient associated with each contaminant at
current concentrations, and the potential cancer risk and hazard quotient associated with
each contaminant at the cleanup concentrations. These risks have been estimated
assuming future use of the ground water as a residential source of drinking and shower
water.
Soil Remediation Criteria
Contaminants of concern for soil remediation include arsenic, lead, PCBs, dioxins,
furans, benzene, cis-l,2-DCE, and vinyl chloride. The "to be considered" (TBC)
remediation criterion for PCBs of 25 mgIkg is based on EPA Directive 9355.4-01FS, "A
Guide- on Remedial Actions at Superfund Sites with PCB Contamination." The TBC
cri~rion for dioxins and furans of 0.001 mg/kg was derived from the "General Approach
Used by the Dioxin Disposal Advisory Group (DDAG) Regarding Pentachlorophenol
Waste (also PCBs)" by P. des Rosiers, November 1988. Remediation criteria for benzene
and vinyl chloride of210 and 3.2 mg/kg, respectively, correspond to cancer risks of 1 x 10-5
under a future residential soil ingestion scenario. The remediation criterion for cis-l,2-
DCE is 700 rng/kg, which corresponds to a hazard quotient of 0.1 under this scenario. The
A-I
-------
TABLE A-I
GROUND-WATER REMEDIATION CRITERIA
BASED ON A FUTURE RESIDENTIAL EXPOSURE SCENARIO
Concentration in Clean-Up
~i8 Level(a) Clean-Up
Chemical Base RiskIHQ (J.1CIL) RiskIHQ
Benzene 13/RME 2 x 1O-5/-(b) 5 7 x 1O-6/--(b)
cis-l,2 -Dich loroethene 15,600/RME . NC/90 70 NC/OA
Vinyl chloride 1501RME 8 x 10-31200 2 1 x 10-4f2
PCBs 110(c)/RME 2 x 1O-2/--(b) 0.5 9 x 1O-5/--(b)
2,3,7,8-TCDD equivalents 0.OO003(c)/RME 6 x 1O-5/-(b) 0.00003 6 x 1O-5/-(b) .
(a)
(b)
(c)
All cleanup levels are MCLs
No reference dose available to calculate the hazard quotient
Concentration reflects turbid samples
H Q Hazard quotient
NC Noncarcinogen
RME Reasonable maximum exposure concentration cotTesponding to the 95 percent
confidence interval of the mean
A-2
-------
criterion for arsenic of 35 mg/kg corresponds to a cancer risk of 1 x 10-4. An arsenic
concentration that corresponds to a potential cancer risk of 1 x 10-5 (3.5 mg/kg) is not
practical at OU 4 because that concentration would be below naturally occurring
background concentrations present at DDOU, whereas, the proposed criterion can be
clearly distinguished from background levels. There is no reference dose or slope factor
for lead, so a cleanup criterion corresponding to a hazard quotient of 0.1 or a cancer risk of
1 x 10-5 cannot be established. The criterion for lead of 500 mglkg is a typical remediation
criterion for residential soils at CERCLA sites.
Risks for soil contaminants were calculated under a residential ingestion scenario where
a person was assumed to be exposed as a 15 kg child ingesting 200 mg of soil per day for six
years, and also as a 70 kg adult ingesting 100 mg of soil per day for 24 years. (This
scenario was developed for the establishment of remediation criteria. It was not part of the
baseline risk assessment for OU 4, and therefore results of this scenario were not included
in Section 3.2 of the Decision Summary of this ROD.) Table A-2 summarizes the
remediation criteria, baseline risks, and post-remediation risks.
It should be noted that most of the remediation criteria for the contaminants of concern
exceed the baseline concentrations detected in soil samples collected from Burial Sites 4-A
and 4-E. While there is no risk-based reason for remediating the soil at au 4, remediation
criteria are necessary should hot spots be encountered where contaminant concentrations
exceed previously detected concentrations.
A-3
-------
TABLE A-2
son. REMEDIATION CRITERIA
BASED ON A FUTURE RESIDENTIAL EXPOSURE SCENARIO
Concentration Clean-Up
in Level Clean-Up
Chemical mg/kg/Basi8 Base RiskIHQ . (mg/kg) Risk'HQ
Benzene 6.3/RME 3x 1O-7/..(a) 210 1 x 1O-5/_-
-------
APPENDIX B
PERFORMANCE AND COMPLIANCE
MONITORING PLAN
-------
APPENDJXB
PERFORMANCE AND COMPLIANCE MONITORING PLAN
PERFORMANCE AND COMPLIANCE MONITORING FOR REMOVAL OF OU 4 SOn.
AND DEBRIS
Remediation Goals
Remediation goals for soil are defined in Section 5.1.1 of the ROD.
Area of Att.JI1-rnnent
The area of attainment for remediation goals is the soil and debris in Burial Sites 4-A, 4-D,
and 4-E. The volume of soil and debris requiring remediation is therefore 4,500 to 5,000
cubic yards. This estimate assumes the one or two feet of clean fill overlying the
contaminated material in each burial area will be replaced in the excavation. Volume
estimates may be revised during the RD/RA based on soil sampling results.
Restoration Time Frame
The restoration time frame for this action is estimated to be approximately six months after
commencement of work on site, and will be completed within 15 months to 24 months after
the ROD is signed.
Performance Standards
Specific performance standards used to ensure attainment of the remediation goals for soil
are:. .
.
Reduce contaminant concentrations in soils within the area of attainment to
comply with the remediation goals specified in Section 5.1.1 of the ROD
.
Meet aU ARARs identified in the ROD for soil
.
The soil will be remediated in a timely manner in compliance with the selected
remedy presented in the ROD to achieve remediation goals as soon as
practicable.
Completion ofF~
Remediation shall be considered complete after the soil remediation goals have been
attained in all samples taken from the perimeter of the excavation. Samples to be used for
compliance monitoring win be specified' during Remedial Design (RD) in the
Performance and Compliance Sampling Program. Sample locations will be approved by
EPA and UDEQ during the RD. The number and location of samples to be taken may be
modified. during remediation to ensure compliance with remediation goals. The
frequency of sampling will be determined during the RD. Any statistical .methods to
average soil concentrations areally or vertically shall be specified during the RD. The
guidance entitled "Methods for Evaluating the Attainment of Cleanup Standards-
Vol urn e 1. Soils and Solid Media" (EP A 230/02-89-042) will be consulted when
establishing the Performance and Compliance Sampling Program.
B-1.
-------
P"2rformance and Compliance Monitoring Program
A Penonnance and Compiiance Monitorjng Program will be implemented during the
remedial action to monitor penonnance and compliance with remediation goals. This
program will be developed during the RD and will include locations of penonnance
monitoring points within Burial Sites 4-A and 4-E, frequency of monitoring, analytical
parameters, sampling methods, analytical methods, and statistical methods for
evaluating data. The Performance and Compliance Monitoring Program will be
included as part of the remedial design but may be modified during the remedial action to
account for changed conditions.
PERFORMANCE AND COMPLIANCE MONITORING FOR REMEDIATION OF
SHALLOW GROUND WATER
Remediation Goals
Remediation goals for shallow ground water are defined in Section 5.1.1 of the ROD.
Area of Att.sll;nment
The area of attainment for remediation goals is defined as the volume of ground water
containing vinyl chloride above its MCL of 2 J,Lg/L and includes ground water
contaminated by cis-1,2-DCE, benzene, TCE, and PCBs at concentrations greater than
their MCLs of 70 J.1.g/L, 5 J,LgIL, 5 J,LgIL, and 0.5 J,LgIL, respectively. The volume of
contaminated ground water within this plume is estimated at 65 million gallons.
Restoration Time frame
The restoration time frame for this action is estimated to be approximately five years after
commencement of work on site.
PerfonDBDce Standards
Specific perfonnance standards used to ensure attainment of the remediation goals for
ground water are:.
.
Reduce contaminant concentrations in ground water within the area of
attainment to comply with the remediation goals specified in Section 5.1.1 of the
. ROD
.
Meet all ARARs identified in the ROD for ground water
.
The ground water will be remediated in a timely manner, in compliance with
the selected remedy presented in the ROD, to achieve remediation goals as' soon
as practicable.
CompJetioD ofF-w-liatinn
As described in Section 5.1 of the ROD, remediation of the ground water in the shallow
aquifer will be considered complete when contaminant concentrations are maintained
below MCLs for a period of one.year, whereupon the treatment system can be turned off.
Monitoring of compliance wells will continue until the next statutory five year review. If
. MCLs are exceeded within this time, ground-water treatment will recommence.
Compliance monitoring well locations will be specified during RD in the Perfonnanc:e
B-2
-------
and Compliance Monitoring" Plan and will be approved by EPA and UDEQ. The frequency
of sampiing may be modified during remediation to ensure compliance with remediation
goals. .
Performance and Compliance Monitoring Program
A Performance and Compliance Monitoring Program wil1 be implemented during the
remedial action to monitor performance and compliance with remediation goals. This
program wil1 be developed during the RD and wil1 include locations of performance
monitoring points within the vinyl chloride plume, frequency of monitoring, analytical
parameters, sampling methods, analytical methods, and statistical methods for
evaluating data. The Performance and Compliance Monitoring Program will be
designed to provide information that can be used to evaluate the effectiveness of the selected
remedy with respect to the following:
.
Horizontal and vertical extent of the plume
.
Contaminant concentration gradients
.
Rate and direction of contaminant migration
.
Changes in contaminant concentrations or distribution over time
.
Containment of the plume
.
Concentrations of contaminants in the treatment system influent and effluent.
The Performance and Compliance Monitoring Program may be modified during the
remedial action to account for changed conditions.
, .
,
B-3
-------
APPENDIX C
FEDERAL AND STATE CHEMICAL AND
ACTION-SPECIFIC ARARs
-------
TABLE C-l
IDENTIFICATION OF FEDERAL CHEMICAL-SPECIFIC AltARs
Applicable!
Relevant
Standard, Requirement, and
Criteria, or Limitation Citation Description Appropriate Comment
Solid Waste Disposal Act 42 USC Sec. 6901-6987
Identification and 40CFR Part 261 Defines those solid wastes No/Ves Identifies wastes that are subjeclto
Listing of Hazardous which are subject io land disposal restrictions under 40
Waste regulation as hazardous CFR 268.
wastes under 40 CFR Parts
262-265, 268, and Parts 270,
(') 271, 124.
,
~
Safe Drinking Water Act 42 USC Sec. 300g
Nationa1 Primary 40 CFR Part 141 Establishes health-based No/Ves Remedial Action Objectives:
Drinking Water standards for public water Vinyl Chloride - 2 ~g/L,
Standards systems (maxi.mum Benzene - 5 ~g/L
contaminant levels). cis-l,2-DCE - 70 ~Ig/L
PCBs - 0.5 ~g/L
TCE - 5 ~/L
National Primary 40CFR Part 142 Establishes. regulations for No/Ves Provides regulatory requirements for
Drinking Water the imp1ementation and exemptions and variance from MCLs
Regu1ations enforcement of 40 CFR Part for synthetic organic chemicals (40
Implementation 141. CFR Part 142.62)
-------
TABLE C-l
IDENTIFICATION OF FEDERAL CHEMICAL-SPECIFIC AltARs
(CONTINUED)
ApplicableJ
Relevant
Standard, Requirement, and
Criteria, or Limitation. Citation Description Appropriate Comment
National Secondary 40 cm Part 143 Establishes welfare-based No/No Ground water will not be used as 11
Drinking Water standards for public water public water system. These criteria
Standards systems (secondary are set primarily for aesthetic and
maximum contaminant taste purposes.
levels).
() Maximum Contaminant Pub. L. No. 99-339, 100 Establishes drinking water No/Yes Relevant and appropriate for
to:> Level Goals Stal 642 (1986) quality goals set at levels of c~ntaminants in ground water at
no known or anticipated OU4.
adverse health effects, with
an adequate margin of
safety.
Clean Water Act 33 USC Sec. 1251-1376
Water Quality Criteria 40 CFR Part 131 Sets criteria for water quality No/Yes Relevant and appropriate to ground-
Quality Criteria for based on toxicity to aquatic water treatment at OU 4.
Water, 1986 organisms and human
health.
Clean Air Act 42 USC Sec. 7401-7642
National Primary and
Secondary Ambient Air
Quality Standards
40 cm Part 50
Establishes standards for
ambient air quality to protect
public health and welfare
(including standards for
particulate matter and lead).
No/Yes
Relevant and appropriate to any on-
site activity which might result in air
emissions during remedial actions at
OU4.
-------
TABLE C-)
IDENfIFICATION OF FEDERAL CHEMICAL-SPECIFIC ARARs
(CONTINUED)
Standard, Requirement,
CrIteria, 01' Limitation Citation Description
National Emission 40 cm Part 61 Sets emission standards for
Standards for Hazardous designated hazardous
Pollutants pollutants.
Occupational Safety and 20 use Sec. 651-678 Regulates worker health and
Health Act safety. . .
o
i" D.O.T. Hazardous Material 49 cm Parts 107, Regulates transportation of
Transportation RellUlatioD8 171- 177 hazardous. materials.
Applicable!
Relevant
and
Appropriate
Comment
Resource Conservation and
RecovEr)' Act
Section 3004(m)
Waives prohibition of limd
disposal of a particular
hazardous waste if levels or
methods of treatment
substantially reduce toxicity
or likelihood of migration of
hazardous constituents to
minimize short and long-
lenn threats to human health
and the environment.
No/Yes
Ye s/ - u
Y es/---
No/Yes
Relevant and appropriate to ground-
water treatment facility air emissions
of vinyl chloride.
Applicable to any remedial action
activity.
Applicable to remedial actions
involving off-Oepot movement of
hazardous materials during
remediation.
Appropriate for remedial alternatives
involving landfilling of
contaminated soil.
-------
TABLE C-t
IDENfIFICATION OF FEDERAL CHEMlCAL-SPECIFIC ARARs
. (CONTINUED)
Standard. Requirement,
Criteria, or LImItation
Citation
Description
Applicable!
Relevant
and
Appropriate
Comment
General Approach Used by
the Dioxin Disposal
Advisory Group IDDAG)
Regarding Pentachloro-
phenol Waste (aI8oPCB8),
des RosIen (1988)
Q
,f..
A Guide on Remedial
Actiona at 8uperl\md 81te8
with PCB C'AJntamination
Recommends a site
evaluation method, cleanup
levels, and treatment
standards for sites known to
be PCB, copper wire/core
reclamation, or PCP wood
treating sites.
EPA Directive
9355.4-0tFS
Summarizes pertinent
considerations in the
development, evaluation,
and selection of remedial
actions. Provides a general
framework for determining
cleanup levels.
No/No
N o/N 0
"To be consid~red." Site evaluation
method, .cleanup levels, and treatment
standards for dioxins and furans.
"To be considered." Suggests cleanup
levels for PCBs on an industrial or
residential site.
-------
TABLE C-2
IDENTIFICATION OF STATE CHEMICAL-SPECWIC AlWIS
Applicablel
Relevant
Standard, Requirement, and
Criteria, or LbnItadon Citation Description Appropriate Comment
Utah Public DrlnkiD, Water Utah Admin. Code Establishes maximum NolYes Requirements are relevant and.
Regulations (U.A_C.) R449 contaminant levels for appropriate to OU 4. Some MCLs
inorganic and organic established for contnminants not
chemicals. Federally regulated (i.e.
Sulphates and total dissolved
solids).
(') Utah Ground-Water QualIty Utah Admin. Code Establishes groundwater Yes/--- Slandards are identical to Utah
b1
Protection RegulatioD8 (U.A.C.) R448-6 quality standards for the Public Drinking Water
different groundwater Regulations but con lain MCLs
aquifer classes- for volatile organics.
Division of Solid and U.A.C. R450-101 Corrective action clean-up Yes/--- Lists general criteria to be
Hazardous Waste, standards policy - RCRA, considered in establishing
Departmentd UST, and CERCLA sites. clean-up standards. Refer to
Environmental Quality Safe Drinking Water Act and
Clean Air Act. Requires
removal or control of the source.
Department 01 AgrIculture U.A.C. Rule R68-07 Pesticide control--safe and No/Yes See particularly R68-07-1O,
appropriate use of pesticides. U.A.C., regarding storage,
transport and disposal, and IUi8-
07-11, U.A.C., regarding other
unlawful acts.
-------
TABLE C-2
IDENTIFICATION OF STATE CHEMICAL-SPECIFIC ARARS
(CONTINUED)
Standard., RequIrement,
Criteria, or Umltation
Citation
Description
Applicable/
Relevant
and
Appropriate
Comment
Division 01 Water Quality,
Department of
Environmental Quality
(')
c!n
Rule R448-1 U.A.C.
Definitions for Water
Pollution Rules and General
Requirements.
Yes/---
Yes/n-
These rules are specific to Utah
waters, though they are derived
in part by using Federal criteria.
See particularly the anti-
degradation policy in U.A.C.
R448-2-3. .
Rule R448-2 U.A.C.
Standards of Quality for
Waters of the State.
-------
TABLE C-3
IDENTIFICATION OF FEDERAL ACTlON.SPECIFIC ARARs
Standard. Requirement,
Criteria, or Umltatton
Citation
National Emission
Standardl for Hazardous
AIr PoUutBntB
40CFRParl.61
80Ud Waste Dispo&aI Ad
42 use Sec. 6901-6987
o
.
~
Guidelines for the Land
Disposal of Solid Wastes
40 CFR Part 241
Criteria for
Classification of Solid
Waste Disposal
Facilities and Pradices
40 CFR Part 257
Description
Designates substances as
hazardous air pollutants and
establishes emission
standards.
Establishes requirements
and procedures for land
disposal of solid wastes.
Establishes criteria for use
in determining which solid
waste disposal facilities and
practices pose a reasonable
probabilily of adverse efTecls
on health or the
environment.
Applicabl6'
Relevant
and
Appropriate
No/Ves
Yes/---
Yes/---
Comment
Relevant and appropriate to vinyl
chloride emissions from on-site
ground-water treatment facilities.
Applicable to remedial alternatives
involving landfill storage of non-
hazardous contaminated soils or
debris such as water purification
tablets. Not applicable or relevantancl
appropriate for hazardous soils.
Applicable to remedial alternatives
involving ofT-site landfilling of
contaminated soils.
-------
TABLE C-3
IDENTIFICATION OF FEDERAL ACTION-SPECIFIC AIW1s
(CONTINUED)
Applicable!
Relevant
Standard, Requirement, and
CrIteria, or LImItation Citation De8cription Applupl1ate Comment
Standards Applicable to 40 CFR Part 262 Establishes standards for Y es/- - Applicable to remedial allernalives
Generators of Hazardous generators of hazardous involving landfilling of hazardous
Waste waste. contaminated soils and debris. Nol
applicable landfilling of hazardous
soils.
~ Standards Applicable to 40 CFR Part.263 Establishes standards which Yes/m Transport of hazardous malerials ofT-
Transporters of apply to persons transporting site may occur during some remedial
Hazardous Waste hazardous waste within the alternatives.
U.S. if the transportation
requires a manifest under 40
CFR Part 262.
Standards for Owners 40 CFR Part 264 Establishes minimum Yes/Yes See discussion of specific subparls.
and Operators of . national standards which
Hazardous Waste define the acceptable
Treatment, Storage, and management of hazardous
Disposal Facilities waste for owners and
operators of facilities which
treat, store, or dispose of
hazardous waste.
. General Facility Subpart B Y est --- Applicable lo ofT-sile landfills.
Standards
-------
TABLE C-3
IDENTIFICATION OF FEDERAL ACTION-SI)ECIFIC ARARs
(CONTINUED)
Applicable!
Relevant
Standard. Requirement, and
Criteria, ... LimItation Citation . Description Appropriate Comment
. Preparedness and Subpart C Yes/--- Applicable to ofT-site landfills.
Prevention
. Contingency Plan Subpart D Yes/--- Applicable lo ofT.sile landfills.
and Emergency
Procedures
(')
,
CD Manifest System, Subpart E Yes/n- Applicable to allernatives involving
.
Record Keeping, and GAC media management and
Reporting disposal, and ofT-site landfill.
. Releases from Solid Subpart F Yes/---. Applicable to off-sile landfill.
Waste Management
Units
. Closure and Post- Subpart G Yes/--- Applicable to ofT-site landfill.
Closure
. Financial Subpart H Ye.s/--- Applicable lo ofT-sile landfiU.
Requirements
. Use and Manage- Subpart.I Yes/--- Applicable lo off-sile landfill. .
ment of Containers
-------
TABLE C-3
IDENTIFICATION OF FEDERAL ACTION-SPECIFIC ARARs
(CONTINUED)
Applicable!
Relevant
Standard, Requirement, and
Criteria, or Limitation Citation Description Appropriate Comment
. Waste Piles' Subpart L N o/Y e ~ Relevant and appropriate to materials
handling operations on site.
. Landfills Subpart N Yes/--- Applicable to off-site landfills.
. Incinerators Subpart 0 Yes/--- Applicable to off-site incineration if
~ necessary for treatment of some soils.
....
0
Interim Standards for 40 CFR Part 267 Establishes minimum No/Yes Remedies should be consistent with the
Owners and Operators of national standards that more stringent Part 264 standards as
New Hazardous Waste define acceptable these represent the ultimate RcnA
Land Disposal Facilities management of hazardous compliance standards and are
waste for new land disposal consistent with CERCLA's goal of
facilities. long-term protection of public health
and welfare and the environment.
Land Disposal 40 CFR Part 268 Identifies hazardous wastes Yes/Yes Applicable to soils containing
Restrictions that are restricted from land FOOI-F005 solvents disposed of off site.
disposal. Relevant and appropriate for on-site
disposal acbvities.
-------
TABLE C-3
IDENTIFICATION OF FEDERAL ACTION-SPECIFIC ARARs
(CONTINUED)
Applicable!
Relevant
Standard, Requirement, and
Criteria, 01' LImItation Citation Description Appropriate Comment
Safe Drinking Water Act 42 USC Sec. 300g
40 CFR Part 136 Sets approyed test methods for No/Yes Relevant and appropriate Lo ground-
waste constituent water treatment.
monitoring.
V' Underground Injection 40 CFR Parts 144-47 Provides for protection of No/Yes Relevant and appropriate to ground.
....
.... Control Regulation8 underground sources of water treatment involving
drinking water. reinjection.
Tmic Substances Control Ad 15 use Sec. 2601-2629
PCB Requirements 40 CFR Part 761 Establishes storage and N o/Y e s Relevant and appropriate as PCB
disposal requirements for concentrations are less than 50 ppm.
PCBs.
Occupational8Bfety and 20 use Sec. 651-678
Health Ad 29CFR Part 1910 Regulates worker health and Yes/.. Applicable to all remedial activiLies.
safety.
D.O.T. Hazardous Material 49 CFR Parts 107,171- Regulates transportation of Yes/.. Applicable to off-site disposal of
'I'ran8portatlon Regulation. IT1 hazardous materials. wastes.
-------
TABLE C-3
IDENTIFICATION OF FEDERAL ACTION-SPECIFIC AJW{s
(CONTINUED)
Standard, RequIrement,
Criteria, or UmltatiOD
Citation
Description
Applicable!
Relevant
and
Appropriate
Comment
Re8ouroe CoDsenration and
Recovery Act
~
~
Section 3020
Interim controls of
hazardous waste injeclion.
Yes/---
Applicable to on-site reinjection of
contaminated ground water treated
under a CERCLA response action.
-------
"
TABLE C-4
IDENTIFICATION OF STATE ACTION-SP"~CIFIC ARAUs
Applicable!
Department, Divlsipn Uelevant and
or Commiision Statute SuIVoct Appiupl-iate Remarks
State Engineer, U.A.C. Rule R625-4 Well drilling standards Yes/--- Includes such requirements as
DepeJtment oINatund -standards for drilling performance standards for
Re8ource8 and abandonment of casing joints, requirements for
wells. abandoning a well, etc.
Indusbial Commls810n U.A.C. Rule R500 Utah Occupational Safety Yes/--- These rules are identical to
and Health Standards. Federal OSHA regulations.
9 DivIsion of Solid and Title 19, Chapter 6, Solid Waste. Not yet N o/Y e s These rules govern solid waste
t; HazardOWI Waste, U.C.A. codified; copy available landfills.
DeputmeDt 01 from the Division of Solid
. Environmental Quality and Hazardous Waste.
U.A.C. Rule R450 Solid and Hazardous Yes/---
Waste.
R450-9, regarding spill reporting
requirements, has no
corresponding Federal
provisions.
U.A.C. Rule R450-101
Corrective Action Clean-
up Standards Policy -
RCRA, .UST, and
CERCLA sites.
Yes/---
Lists general criteria to be
considered in establishing
clean-up standards including
compliance with MCLs in Safe
Drink:ng Water Act and Clean
Air Act. Requires removnl or
control of the source.
-------
TABLE C-4
IDENTIFICATION OF STATE ACTION-SPECIFIC ARAlts
(CONTINUED)
Department, Division
or Commission
Statute
SuIVed
ApplicableJ
Relevant and
App-opriate
Itemarks
Division otWater Quality,
Depmtmentol
Environmental Quality
~
....
"..
Division of Air Quality,
Dq.u tuhmtol
Enviromnental Quality
U.AC. Rule R446-3
U.AC. Rule 448-7
U.AC. Rule 448-6
U.AC. Rule R446-1
Sewers and wastewater
treatment works.
N o/Y e s
Construction and performance
requirements.
See particularly R448-7-9
specifying technical
requirements.
There is no corresponding
federal program.
Requires application of best
available control technology for
any source, lists criteria to be
consid~red in establishing
visibility standards, sets visible
emission standards, rebrulates
fugitive dust emissions, allows
the State to require temporary
closure of air pollution sources in
the event of an air pollution
emergency episode, and includes
a limit of 1.5 tons of annual
emissions of VOCs without
obtaining a permit.
Underground injection
control.
Yes/---
Groundwater Quality
Protection.
Yes/ n-
Utah Air Conservation
Rules.
N o/Ye s
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