United States
Environmental Protection
Agency
Office of
Emergency and
Remedial Response
EPA/ROD/R09-89/040
September 1989
&EPA
Superfund
Record of Decision
Purity Oil Sales, CA
-------
50272-101
REPORT DOCUMENTATION i. REPORT Na
PAGE EPA/ROD/R09-89/040
4. Title and Subtil)*
SUPERFUND RECORD OF DECISION
Purity Oil Sales, CA
First Remedial Action
7. Author(s)
9. Performing Organization Name and Addreae
12. Sponsoring Organization Nama and Address
U.S. Environmental Protection Agency
•401 M Street, S.W.
Washington, D.C. 20460 ' .
2. 3. Recipient- e AccaaaJon No.
5. Report Date
09/26/89
6.
8. Performing Organization Rept No.
10. Pro|ect/Taak/Work Unit No.
11. Contract(C) or Grant(C) No.
(C)
(C)
13. Type of Report & Period Covered
800/OGO
14.
15. Supplementary Notea
16. Abet/act (Limit: 200 word*)
The seven-acre Purity Oil Sales site is in Fresno County, California, one-half mile south
of the Fresno city limits. The site is located in a predominantly industrial area,"
however, there are adjacent residential properties, including three houses and a trailer
park. The ground water aquifer in the Fresno area has been designated as a sole-source
aquifer. The shallow aquifer underlying the site is probably hydrogeologically connected
with deeper aquifer zones providing domestic water supply for Fresno and the surrounding
area. The Purity site operated as a used oil recycling facility from 1934 to the early
1970s. In 1976 a fire destroyed the main warehouse building. Equipment remaining, with
the exception of seven steel above-ground storage tanks, was removed from the site, and th
area was partially regraded. One of the remaining storage tanks is lined with asbestos.
Waste pits filled with soil, debris, and rubble, cover most of the site. The State
conducted a remedial investigation in 1982 during which time the EPA Emergency Response
Team removed 1,800 cubic yards of hazardous oily and tarry materials from the site. This
first of two planned operable units addresses the cleanup of the ground water and the
removal and offsite disposal of storage tanks and tank contents. A future Record of
Decision (ROD) will address contaminated soil. The primary contaminants of concern
affecting ground water are VOCs including benzene and TCE; and metals. Contaminants of
concern in the tank sludge are VOCs including benzene, toluene and xylenes; other organics
including PCBs, PAHs, pesticides, and phenols; and metals (Continued on next page)
17. Document Anatyaia a. Descriptor*
Record of Decision - Purity Oil Sales, CA
First Remedial Action
Contaminated Media: tank sludge, gw
Key Contaminants: VOCs (benzene, TCE, toluene,
pesticides, phenols), metals (lead>
b. Identifiers/Open-Ended Terms
c. COSATt FMd/Group
18. Avaiiabilty Statement
»•
xylene) , other organics (PAHs, PCBs,
a
1». Security Class (This Report) 21. No. of Page*
None 58
20. Security Class (Thto Psg*>) 22. Price
None
(See ANSI-Z39.18)
SM (rutructfon* on Rewane)
OPTIONAL FORM 272 (4-77)
(Formerly NT1S-15)
Department of Commerce '
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DO NOT PRINT THESE INSTRUCTIONS AS A PAGE IN A REPORT
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1. Report Number. Each individually bound report shall carry a unique alphanumeric designation assigned by the performing orga-
nization or provided by the sponsoring organization in accordance with American National Standard ANSI Z39.23-1974, Technical
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uppercase letters, Arabic numerals, slashes, and hyphens only, as In the following examples: FASEB/NS-75/87 and FAA/
RD-75/09.
2. Leave blank.
3. Recipient's Accession Number. Reserved for use by each report recipient
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8. Performing organization Report Number. Insert if performing organizaton wishes to assign this number.
9. Performing Organization Name and Mailing Address. Give name, street, city, state, and ZIP code. List no more than two levels of
an organizational hierachy. Display the name of the organization exactly as it should appear In Government Indexes such as
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10. Project/Task/Work Unit Number. Use the project, task and work unit numbers under which the report was prepared.
11. Contract/Grant Number. Insert contract or grant number under which report was prepared.
12. Sponsoring Agency Name and Mailing Address. Include ZIP code. Cite main sponsors.
13. Type of Report and Period Covered. State interim, final, etc., and, if applicable, inclusive dates.
14. Performing Organization Code. Leave blank.
15. Supplementary Notes. Enter information not Included elsewhere but useful, such as: Prepared in cooperation with ... Translation
of... Presented at conference of... To be published in... When a report Is revised, include a statement whether the new
report supersedes or supplements the older report
16. Abstract. Include a brief (200 words or less) factual summary of the most significant Information contained In the report. If the
report contains a significant bibliography or literature survey, mention It here.
17. Document Analysis, (a). Descriptors. Select from the Thesaurus of Engineering and Scientific Terms the proper authorized terms
that identify the major concept of the research and are sufficiently specific and precise to be used as Index entries for cataloging.
(b). Identifiers and Open-Ended Terms. Use Identifiers for project names, code names, equipment designators, etc. Use open-
ended terms written In descriptor form for those subjects for which no descriptor exists.
(c). COSATJ Field/Group. Field and Group assignments are to be taken form the 1964 COSATJ Subject Category List. Since the
majority of documents are multldisclpllnary in nature, the primary Reid/Group assignments) will be the specific discipline,
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18. Distribution Statement Denote public releasability, for example "Release unlimited", or limitation for reasons other than
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GPO 19830-381-526(8393.) OPTIONAL FORM 272 BACK
(4-77)
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EPA/ROD/R09-89/040
Purity Oil Sales, CA
16. Abstract (Continued)
including lead.
The selected remedial action for this site includes of ground water pumping and onsite
treatment with greensand to remove metals and air stripping to remove VOCs; disposal of
treated ground water by either reinjection into the aquifer, disposal in a canal or
disposal in local infiltration basins; provision of an alternate water supply to affected
private well owners; creation of a ground water management zone to maintain ground water
levels; ground water monitoring; removal, onsite solidification, (if necessary), and
offsite disposal of 22,500 gallons of contaminated sludge from the seven onsite steel
tanks; and cleaning, dismantling, and offsite disposal of the tanks including appropriate
offsite disposal of the asbestos walled tank. In addition, treatability studies will be
conducted on the site soil to determine the effectiveness of several emerging treatment
technologies. -The estimated present worth cost for this remedial action is $11,660,000,
which includes a total cost of $500,000 for removal of_the steel tanks. A present worth
O&M cost of $6,960,000 is included in the total present worth estimate.
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RECORD OF DECISION
FOR THE
PURITY OIL SALES, INC.
SUPERFUND SITE,
GROUNDWATER AND TANKS
OPERABLE UNIT
Prepared by
The U.S. Environmental Protection Agency
Region DC
San Francisco, California
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RECORD OF DECISION
FOR THE
PURITY OIL SALES
SUPERFUND SITE,
GROUNDWATER AND TANKS
OPERABLE UNIT
PREPARED BY
THE U.S. ENVIRONMENTAL PROTECTION AGENCY
REGION IX
SAN FRANCISCO, CALIFORNIA
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TABLE OF CONTENTS
PURITY RECORD OF DECISION
Groundwater and Tanks Operable Unit
Section Page
Declaration for the Record of Decision i
Decision Summary 1
I. Site Name, Location and Description l
II. Site History and Enforcement Activities 4
III. Community Relations 7
IV. Scope and Role of the Operable Unit 8
V. Site Characterization 9
A. Contaminated Surface Soils 9
B. Buried Wastes and Contaminated Subsurface Soils. . 9
C. Onsite Steel Tanks 11
D. North Central Canal Water and Sediment 15
E. Groundwater 15
F. Air 23
VI. Risk Assessment Summary 23
A. Chemicals of Concern 23
B. Exposure Pathways 23
C. Risk Characterization 25
VII. Changes to the Proposed Plan 26
VIII. Groundwater Alternatives 26
A. Alternative Wl 28
B. Alternatives W2 and W3 28
C. Implementation Elements for Alternative W3 .... 34
IX. Tank Removal Alternatives 38
X. Applicable Or Relevant and Appropriate Requirements
(ARARS) Analysis '" 39
XI. Comparative Analysis of Alternatives 39
A. Short-term Effectiveness 39
B. Long-term Effectiveness 47
C. Reduction in Toxicity, Mobility and Volume. . . .47
D. Implementability 48
E. Compliance with ARARS 48
F. Costs 49
G. Overall Protection 49
H. State and Community Acceptance 49
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DECLARATION FDR THE RECORD OF DECISION
SITE NAME AND LOCATION
The Purity Oil Sales (Purity) site is located in Malaga, Califor-
nia, one-half mile south of the City of Fresno, in California's
Central Valley.
STATEMENT OF BASIS AND PURPOSE
This decision document represents the selected remedial action for
the Purity site groundwater and tanks operable unit, developed in
accordance with the Comprehensive Environmental Response, Compen-
sation and Liability Act of 1980, as amended, and the National
Contingency Plan. This decision is based on the administrative
record for this site. (The attached index identifies the items
which comprise the administrative record upon which the selection
of the remedial action is based). The State of California has
concurred on the selected remedy.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from the
site, if not addressed by implementing the response action
selected in this ROD, may present an imminent and substantial en-
dangerment to public health, welfare or the environment.
DESCRIPTION OF THE SELECTED REMEDY
This Record of Decision (ROD) for the Purity site includes the
following actions to address contaminated groundwater and tanks:
o Water treatment to remove volatile organic compounds (VOCs),
iron and manganese from the groundwater, including:
- Extraction of contaminated groundwater to attain federal and
state drinking water standards in the aquifer
Treatment of contaminated groundwater using greensand and
air stripping. Carbon adsorption will be used to control
air emissions, if needed
Disposal of treated and tested groundwater by use of one or
more of the following methods: reinjection into the
aquifer, disposal in the North Central Canal or disposal in
local infiltration basins
Groundwater monitoring to verify contaminant clean-up
Provision of an alternate water supply to affected private
well owners located northwest of the site
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XII. The Selected Remedy 50
A. Groundwater Treatment 50
B. Removal of Steel Tanks 50
XIII. Statutory Determinations 50
A. Protectiveness 51
B. Environmental Impacts 51
C. Compliance with ARARS 51
D. Cost-effectiveness 51
E. Use of Permanent Solutions and Alternative
Technologies to the Maximum Extent Practicable . 51
F. The Preference for Treatment 52
XIV. Attachments
A. The Administrative Record Index
B. The Responsiveness Summary
Table 1 - Soil Cleanup Goals 10
Table 2 - Estimates of Tank and Waste Volumes 13
Table 3 - Tank Characteristics and Conditions 14
Table 4 - Groundwater Cleanup Goals 17
Table 5 - Contaminants of Concern 24
Table 6 - ARARs Analysis 40
Figures
Figure 1 - Site Location Map 2
Figure 2 - Vicinity Land Uses 3
Figure 3 - Site Layout, 1942-1973 5
Figure 4 - Tank Locations 12
Figure 5 - Rounds 1 and 2 Concentrations of VOC's 18
Figure 6 - Groundwater Sampling Results, Round 3 19
Figure 7 - Rounds 1 and 2 Concentrations of Iron 20
Figure 8 - Rounds 1 and 2 Concentrations of Manganese. ... 21
Figure 9 - Location of Private and Municipal Wells 22
Figure 10 - Proposed Cleanup Target Areas 27
Figure 11 - Proposed Extraction Wells and Zones of Capture
for Alternative W2 29
Figure 12 - Proposed Extraction Wells and Zones of Capture
for Alternative W3 30
Figure 13 - Water Treatment Process Diagram 32
Figure 14 - Possible Monitoring Well Locations 35
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Creation of a groundwater management zone extending 1-2
miles from the cleanup target area, to control pumping to
maintain groundwater levels at the desired configuration
o Tank Removal
Removal and off-site disposal of contaminated wastes in the
seven onsite steel tanks
Solidification of wastes, if needed, prior to offsite dis-
posal
Cleaning, dismantling and off-site disposal of tanks
DECLARATION
The selected remedy is protective of human health and the eviron-
ment, attains federal and state requirements that are applicable
or relevant and appropriate to this remedial action and is cost-
effective. The remedy satisfies the statutory preference for
remedies that employ treatment that reduces toxicity, mobility or
volume as a principal element and utilizes permanent solutions to
the maximum extent practicable.
Because of the anticipated length of time to achieve the cleanup
goals, and the uncertainty as to whether the cleanup goals can be
achieved, both the technologies and the cleanup goals will be
reassessed every 5 years. The State of California has written a
letter of concurrence on this ROD.
Daniel W» McGovern Date
Regional Administrator
11
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DECISION SUMMARY
I. SITE NAME. LOCATION AND DESCRIPTION
The 7 acre Purity site is located about one-half mile south of
the city limits of Fresno (Figure 1). The site is located in
the center of California's San Joaquin Valley. The Purity site
operated as a used oil recycling facility from 1934 co the
early 1970's.
The site is located in a predominantly industrial area, but has
some adjacent residential properties. Properties immediately
adjacent to the site include railroad tracks, a scrap metal
yard, a residential trailer park, a small market, a propane
distributor, a small farm, several residences, and a used auto
salvage yard (Figure 2). It is estimated that the auto salvage
yard has 72 employees and is visited by 22,000 customers each
month. Approximately 180 residents live in the trailer park.
The trailer park has about 50 trailers and 10 cabins. Some
trailers are located immediately adjacent to the site fence.
The small market has a backyard and residential apartment. Im-
mediately southeast of the site are three houses with two or
three people living in each house.
Under the Fresno County General Plan, the Purity site is in a
zone defined as heavy industrial and is intended to provide for
all manufacturing uses, including the heaviest and most inten-
sive types. Fresno County is proposing to create an enterprise
zone within the next 15 years, encompassing the Purity site and
surrounding land. Future industrial-commercial development
around the site could be extensive under this program.
About one-half mile to the west and southwest of the site are
fields of oats, alfalfa, cotton, fruit trees, and grapes. The
town of Malaga, which has a medium density residential area,
surrounds the site at distances of about one-half mile and
more.
The Purity Oil site is located in the San Joaquin River
drainage basin. The San Joaquin River is approximately 12
miles north of the Purity site. There are no natural water-
courses in the vicinity of the Purity site. Several irrigation
canals flow in the region, including the North Central Canal
along the southern site boundary.— The North Central Canal is a
lateral of the Central Canal. The Central Canal eventually
dead-ends approximately 10 miles from the Purity site and has
no outlet to any surface drainage course.
The groundwater aquifer in the Fresno area has been designated
as a sole-source aquifer by EPA under the Safe Drinking Water
Act. The Fresno sole-source aquifer is bounded by the San Joa-
quin River to the north, Friant-Kern Canal to the east, Fresno
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• FRESNO
mile
RDD63320.RI
FIGURE 1
SITE LOCATION MAP
REMEDIAL INVESTIGATION REPORT
PURITY OIL SALES SITE
FRESNO, CALIFORNIA
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CHEMICAL
MANUFACTURING—
COTTON COMPRESSOR
CONSTRUQTION
STORAGE
ARD '
MANUFACTURING
-
-..
FIGURE 2
VICINITY LAND USES
REMEDIAL INVhSIK.AIION HEHUIIT
PUHITY Oil SALES SUE
FRESNO. CALIFORNIA
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Slough to the west, and the Fresno County line to the south,
and includes the Purity site within its boundaries.
The aquifer in the vicinity of the site is unconfined to depths
of several hundred feet. Because there is no confining clay
zone layer to restrict vertical groundwater flow, the shallow
aquifer underlying the Purity site is probably hydrogeologi-
cally connected with deeper aquifer zones which provide domes-
tic water supply for the City of Fresno and surrounding area.
Depth to groundwater at the site is between 40 and 50 feet.
The present direction of groundwater flow is toward Fresno (the
northwest).
The Purity site is located in a non-attainment area for the
following air quality standards: ozone, CO and PM-10. As in-
dividual constituents, the area is attainment for N02, S02 and
HC.
Since the area surrounding the Purity site is primarily in-
dustrial, neither the site nor the surrounding areas provide
habitat or sustain any rare or endangered species of plant or
animal. There are no signs of any significant wildlife or
vegetation, or any habitat on the site itself, other than scrub
grasses.
Seven steel tanks are present onsite at above-ground locations.
The tanks are believed to have been used to store oil prior to
reprocessing, and during the acidification process. One of the
tanks has an exterior asbestos coating. Waste pits up to ten
feet deep cover most of the site, but have been filled since
the early 1970's with soil, debris and rubble. The site is
mostly flat with the western two-thirds of the site 3-5 feet
above the surrounding land due to the presence of the fill
material.
II. SITE HISTORY AND ENFORCEMENT ACTIVITIES
Beginning in 1934, used oil was recycled at the Purity site.
The used oil was taken to the site from businesses such as
service stations, car dealers, truck stops, electrical trans-
former yards and military facilities. The used oil was refined
using a number of treatment processes including clarification,
chemical addition, dehydration, distillation and filtration.
The oil and by-products from the__refining process were col-
lected and stored in sumps and storage tanks and were disposed
of onsite in sludge pits. A composite sketch of the ap-
proximate locations of the buildings, storage areas, and waste
disposal areas from 1942 to 1973 is shown in Figure 3.
The original owners of the recycling facility were William
Dickey and Ray Turner, who operated the facility from 1934 to
1948. In 1948, William Siegfried and Robert Hall purchased the
site as Paraco Oil, Inc. The site and facilities were sold to
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Horizontal Tank*
Horizontal Tank
Impoundment
Double - Biy Warehouse
Tank*
3. May 19. 1942
Approximate Scale 1:5200
Double - Bay
Warehouse
Pit
C. 1957 to 1967
Present In 1957 and 1961 Photographs
J888o
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Michael Marcus of Purity Oil Sales, Inc., in 1965. In June
1973, Purity Oil began complying with a court order to empty
and backfill the waste pits. Although the waste pits were
backfilled by January 1975, there is no evidence that the pits
were emptied. In January 1974, the maintenance foreman at
Purity Oil Sales, Odis Johnson, arranged to purchase the
facilities and lease the property from Michael Marcus. In
March 1975, Odis Johnson informed the Fresno County Health
Department that he was selling the equipment and would not
operate the facilities. Also in 1975, Michael Marcus filed for
bankruptcy, and the site was held by the State of California
for nonpayment of taxes.
A fire at the site in 1976 destroyed the main warehouse build-
ing and adjacent equipment. The remaining equipment was
removed from the site, and the area was partially regraded.
Several steel tanks were all that remained. In 1979, the State
of California sold the property to William Enns. In 1980, the
Department of Health Services (DHS), informed William Enns of a
serious hazardous waste problem on his property and requested a
cleanup plan. Enns went to court requesting recession of the
sale. In 1982, the recession was granted and the site was
returned to the custody of the State of California.
The Central Valley Regional Water Quality Control Board (RWQCB)
obtained surface-water samples from the North Central Canal in
1980. One year later, the RWQCB also conducted groundwater
sampling from private wells near the site. In February 1982,
the EPA Emergency Response Team, DHS, and RWQCB carried out a
joint site investigation that included surface and subsurface
soil sampling, monitoring well installation, and groundwater
sampling. Air quality data were also obtained to monitor the
release of vapors during sampling and drilling. This inves-
tigation indicated that the onsite soil and groundwater con-
tained volatile organic compounds, semi-volatile organic com-
pounds and inorganic compounds which may pose a threat to human
health and the environment. The site was included on the EPA
National Priority List in December 1982.
DHS was designated the lead agency for the site and in 1983,
retained Harding Lawson Associates (HLA) to perform the
Remedial Investigation. Field explorations and chemical test-
ing performed by HLA were comple.ted in September 1984. A
Remedial Investigation Report was issued on May 12, 1986.
During HLA's Remedial Investigation, the EPA Emergency Response
Team removed about 1,800 cubic yards of hazardous oily/tarry
materials from the site.
In January 1986, EPA assumed the lead for the site and retained
CH2M HILL to expand the Remedial Investigation work performed
by HLA to include additional soil and groundwater studies. The
purpose of this supplemental work was to complete the evalua-
tion of the nature and extent of the soil and groundwater con-
tamination onsite and in the site vicinity, to characterize
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pathways of contaminant migration offsite, and to determine
risks to human health and the environment fro;.i the con-
taminants. New data were collected to fill gaps in the chemi-
cal data for the onsite soils and to provide new information on
the nature and extent of the groundwater contamination. The
Remedial Investigation (RI) Report prepared by CH2M HILL was
submitted to EPA in October 1988. The data collected by CH2M
HILL were validated using EPA approved methods. The Public
Health Evaluation was issued by EPA in March 1989. EPA
released a Feasibility Study in April 1989 to present alterna-
tives for cleaning up the site. The Proposed Plan for tr.~ site
was circulated for public review and comment period in April
1989, and a public meeting was held April 26.
Currently, renewed efforts are underway to determine whether
viable Potentially Responsible Parties (PRP's) exist and who
they are. Information requests authorized under the Resource
Conservation and Recovery Acf(RCRA) and the Comprehensive En-
vironmental Response, Compensation and Liability Act (CERCLA),
RCRA § 3007/CERCLA § 104(e), were issued to some PRP's in 1983.
Responses were received and a PRP search report was issued in
1985. However, these documents were inconclusive. Based on
current investigative work, additional 104(e) letters, general
notice letters and special notice letters authorized under
CERCLA, will be issued. The special notice letters will re-
quire the PRP's to submit a good faith offer to undertake
design and construction of the remedial actions prescribed by
the ROD.
III. COMMUNITY RELATIONS
The following is a summary of community relations activities
required under Sections 113 (k)(2)(i-v) and 117 of CERCLA and
conducted by DHS and EPA for the Purity site. All DHS and EPA
fact sheets were printed and distributed in Spanish and
English. A Spanish interpreter was provided at community meet-
ings.
Date Activities
August 1983- DHS and EPA community relations (CR) repre-
March 1984 sentatives conducted community assessment in-
terviews with interested community members in
the Malaga area ajid completed the Community
Relations Plan.
March 1984 DHS held a community meeting to discuss site
background and health survey results.
August 1984 DHS distributed a fact sheet providing a
brief status report on site activities.
April 1987 Information repositories were established.
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June 1987
March 1988
February 1989
April 1989
April 26, 1989
September 1989
Notice was given to site neighbors requesting
permission to conduct sampling activities on
neighborhood property.
EPA distributed a fact sheet detailing site
history, the Superfund process, current site
activities and opportunities for community
involvement.
A letter was distributed to the Tall Trees
Mobile Home Park residents notifying them of
the potential health hazards of trespassing
onto the site.
EPA distributed a fact sheet detailing the
results of the Remedial Investigation.
EPA distributed a fact sheet explaining the
contents of the Feasibility Study and outlin-
ing the Proposed Plan. The upcoming comment
period and community meeting were also an-
nounced.
EPA held a community meeting to explain the
Feasibility Study report and to receive
public comment on EPA's Proposed Plan for
addressing the soil and groundwater
contamination at the site.
Notice of this ROD, or Final Plan for the
groundwater and tanks operable unit, will be
published and made available to the public
before commencement of the remedial action.
IV. SCOPE AM) ROLE OF THE OPERABLE UNIT
This groundwater and tanks operable unit (OU) will be supple-
mented later by a soils operable unit ROD, to ultimately affect
cleanup of the entire Purity site. The groundwater OU ROD will
enable design and cleanup of the contaminated aquifer and
removal of the tanks to proceed as quickly as possible. This
will reduce the possibility of groundwater contamination
spreading, and prevent the contirmed use of contaminated water
by private well owners. Removal of the tanks will eliminate a
nuisance and potential health hazard from the site.
Treatability studies will be conducted on the site soils, to
determine the effectiveness of several emerging treatment tech-
nologies. Following treatability studies, a ROD for the soils
OU will be prepared. The soils OU ROD will address the con-
tinuing source of groundwater contamination from the site and
will therefore augment this groundwater ROD.
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V. SITE CHARACTERIZATION
The following section briefly describes soil and groundwater
contamination at the Purity site. Although soils cleanup al-
ternatives will not be addressed in this ROD, this section will
briefly describe the nature of the soil contamination. This
soil information is relevant since the contaminated soils are a
source of groundwater contamination, and in order for the
proposed groundwater remedy to be effective, the source will
need to be remediated.
CONTAMINATED SURFACE SOILS
The contaminated surface soils extend vertically to a depth of
approximately two feet and are defined as the eastern 2.5 acres
of the site where the plant facility was located. Waste pits
were not located in this area. These surface soils are con-
taminated with organic compounds, pesticides, oil and grease,
and a variety of metals. Some of the areas of surface con-
tamination were cleaned up by EPA in 1985, as part of a Removal
Action.
The levels of organic compounds in the surface soils are
generally below the California Total Threshold Limit Concentra-
tions (TTLC) values for definition as a state hazardous waste.
The level of pesticides exceed the California TTLC at one loca-
tion. All metals except lead were below the California TTLC.
Lead concentrations in the surface soils ranged from 330 to
5,680 mg/kg, with only one sample exceeding the California TTLC
value of 1,000 mg/kg. Based on testing done to date, the sur-
face soils have not been determined to be Resource Conservation
and Recovery Act (RCRA) characteristic or listed wastes.
Risk based cleanup goals for lead, aldrin, dieldrin, heptachlor
epoxide, and PCB concentrations in the surface soils were ex-
ceeded. These concentrations are presented in Table 1. Addi-
tional cleanup goals based on groundwater protection and con-
stituent solubility will be developed in consultation with the
Regional Water Quality Control Board and included in the soils
ROD.
BURIED WASTES AND CONTAMINATED SUBSURFACE SOILS
The buried wastes and contaminated^ subsurface soils are located
on the western 4.5 acres of the site and contain demolition
debris, soil and oily waste pits. The buried wastes are verti-
cally identified as four mixed layers (Layers A, B, C and D).
The top two layers (Layers A and B) contain approximately
55,000 cubic yards of material and vary in depth from 2 to 14
feet below the present ground surface. This waste zone con-
tains construction debris, steel pipes, soil and oily sludge.
The sludge contains a variety of organic contaminants including
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T.bl. 1
SOIL CLFANUP GOALS
PURITY OIL SITE
(»g'kg)
Cleanup Coal
(atebllahed bjr Reference
Dot* lull nun Alloveble
CnDDOund
1 NORCAN 1C CONS 1 1 TIIF.W T
Bur lure
Rerrlllum
Cadmlim
Chromium
l.ead
Hercury
Silver
Zinc
PRCAHICS
Phenol
Aldiln
Dleldrln
H»ptarhlor Cipoilde
PCB
Hailiaun Soil
Cnnrenl rat Ion
Detected'
1,7*0.0
1.50
71.0*
11.0
34,000.0
0.90
II. 0
5,800.0
iO.OO
0.100
0.15
l.»
11.00
Average Soil
Concent rat Ion
Detected'
125. 0
o.io;
«.*25
13. «0
1,348. 10
O.lti
9.051
119.*
11.00
».o;§
O.IJ9
o.ia;
4.0*5
tupoauta
Cleanup Coll Eetabllfhed b* a 10"* Cancer tiak--Kuoau» Proa Inaeetlon
Mailman ExDOfure Mo.t Probable Kiwoeuc* Child"
Rraldrntal o>:cuoat lonal Treapaeaera Realdentlal Occupational TraiDaaaara Reaidentlal
j.500
J50
15
150
;o
100
150
10,500
i.ooo
0.030
0.0*«
0.093
0.101 0.201 -- 1.14* 1.011
lion Inieatlon
Adult
Reeldentlal and
Occupational
35.000
3.500
350
3,500
980
1,400
2.100
147,000
28,000
--
--
--
*8aerd on a 10-kg child Ingratlng 0.2 g/da* of aurface aoll.
''laard on a 70-kg adult ingeatlng O.I g/day of aurface aotl or deep aoll
'Surface eamplea and ehallov borlnga vlthln the alte boundrlea onlf.
'single trat on HLA boring. Next hlgheat value 17
RDDfP.90/017.50
-------
benzene, toluene, xyiene, polyaromatic hydrocarbons, phenols,
chlorinated ethenes and ethanes, and chlorobenzene. Lead con-
centrations exceed the California TTLC value for disposal as a
hazardous waste in all onsite borings where oily sludge was en-
countered. The levels of other constituents detected did not
exceed TTLC values.
The bottom two layers (Layers C and D) contain approximately
117,000 cubic yards of materials and vary in depth from ap-
proximately 10 to 40 feet below the ground surface. These
soils also contain a variety of organic contaminants, but their
concentrations decrease rapidly below Layers A and B. Lead
concentrations in three samples from the bottom two layers of
soils exceeded the California TTLC value.
Based on testing done to date, the buried wastes and subsurface
soils have not been determined to be RCRA characteristic or
listed waste. Additional testing is being done on these wastes
to determine whether they will be RCRA characteristic wastes
based on the TCLP test and to determine possible land ban ap-
plicability. Lead was the only constituent that exceeded risk
based cleanup goals in layers A, B, C, and D for buried wastes.
Cleanup goals to protect groundwater quality based on con-
stituent solubility will be developed for buried wastes in con-
sultation with the RWQCB, for the soils ROD.
ONSITE STEEL TANKS
Seven above-ground steel tanks are present onsite at locations
shown in Figure 4. Table 2 shows the estimated tank and waste
volumes, and Table 3 describes their condition. They contain
up to two feet of tar, wood and contaminated soil. One tank
has an asbestos coating. Although the tanks are not leaking
severely, the steel on all of the tanks is rusting. Slight
seepage can be observed from several of the tanks during ex-
tended warm weather periods. All tanks contain oily sludge,
and in several the oily sludge is combined with soil. No flow-
able oil or water phases were found in the tanks.
The contaminants identified in the samples taken from the tanks
were similar to the contaminants in the buried wastes, although
relative values were higher in the tanks for most compounds.
Of the inorganic constituents, samples from five tanks (Nos. 1,
3,5,6 and 7) exceeded the TTLC values for lead for designa-
tion as a state hazardous waste. Lead concentrations in Tanks
5 and 7 exceeded the Extraction Procedure (EP) toxicity value
for definition as a RCRA characteristic hazardous waste, as
well, zinc concentrations in Tank No. 4 exceeded the TTLC
value.
Of the organics, PCB concentrations above the TTLC value were
detected in samples from Tank No. 5. 4,4-DDD levels exceeding
11
-------
CENTRAL CANAL
DATE OF.-WHOTOOfi
a
FIGURE 4
TANK LOCATIONS
REMEDIAL INVESTIGATION REPORT
PURITY OIL SALES SITE
FRESNO. CALIFORNIA
-------
Table 2
ESTIMATES OF TANK AND WASTE VOLUMES
Steel
Tank
Area
Number
Tl
T2
T3
T4
T5
T6
T7
Estimated
Tank Volume
(aallons)
44,000
110,000
i
53,000
10,000
5,000
16,000
11,500
Estimated
Waste Volume
(aallons)
2,500
9,200
5,500
2,000
300
1,500
1 ,500
Waste Type
Thick oily sludge
Oily sludge
(3,700 gal)
Thick sludge
(5,500 gal)
Thick sludge
Thick sludge
Oily sludge
Thick sludge
Oily sludge
Scrap
Surface
(ft^)
1 ,440
2,600
1,660
690
350
900
700
13
-------
Table 3
TANK CHARACTERISTICS AND CONDITIONS
Tank
Number
Tl
T2
T3
T4
T5
T6
T7
Diameter Height
(ft) (ft) Shape Construction
22 15 Cylinder
35 15 Cylinder
30 10 Cylinder
15 8 Square
i
9 10 Cylinder
15 17 Cylinder
w/ bottom
cone
13 14 Cylinder
w/ bottom
cone
Welded
steel
Welded
steel
Welded
steel
Riveted
steel
Welded
steel
Welded
steel
Welded
steel
Foundation
Concrete
Concrete
Soil
Wood
(tank on
side)
I-beam
legs
I-beam
legs
(tank on
side)
Top
Open,
no roof
Open,
partial
wooden
roof
Open,
no roof
18-inch
manhole
on top
Open
18-inch
access
portal
18-inch
access
portal
Condition
Poor; battered;
evidence of
leakage
Poor; partially
collapsed; open
hole near base
Poor; partially
collapsed
Poor; exterior
coating of fib-
rous material
partially
stripped
Poor ; tank
lying on side;
hole in bottom
Poor; partial
scaffolding;
evidence of
leakage from
bottom port
Poor ; tank
lying on side;
partially
collapsed;
evidence of
sludge loss
from top
opening
14
-------
the TTLC value in Tanks No. 2 and 4, were also detected. Risk:
based cleanup goals were not established for the tanks, since
they were assumed to be temporary structures.
NORTH CENTRAL CANAL WATER AND SEDIMENT
Pesticides were detected in sediment samples taken from the
North Central Canal near the site, but were below California
TTLC values and may be due to local agricultural practices
rather than site contamination. Lead concentrations in samples
taken from locations along the canal slopes above the water
surface ranged from 1,200 mg/kg to 13,200 mg/kg and exceeded
the California TTLC. All of the metals concentrations in the
canal bottom sediments were below the California TTLC. Exist-
ing data indicate the quality of the canal water remains essen-
tially constant for constituents analyzed upstream and
downstream of the site. The canal sediments will be remediated
along with the site soils and wastes.
GROUNDWATER
The water-bearing sediments in the Fresno area consist of in-
terbedded lenses and layers of materials ranging from clays to
gravels. Silty sands, silts and sands are the predominant soil
types encountered beneath the site. As previously stated, the
groundwater aquifer in the site vicinity is unconfined to
depths of several hundred feet and flows in a northwesterly
direction, with depth to groundwater between 40-50 feet.
The groundwater beneath the site is contaminated by a variety
of organic and inorganic constituents. The contaminated plume
extends at least to an irrigation well located approximately
2,800 feet downgradient of the site. It appears likely that
the contamination extends between 2,800 and 5,600 feet
downgradient of the site, although it is possible that the ir-
rigation well has limited the quantity of contaminants moving
past 2,800 feet.
It is estimated that the vertical extent of groundwater con-
tamination extends to depths of 90 to 130 feet. At the
downgradient edge of the plume, the vertical extent has not
been defined. Additional well installation and sampling is
planned for the near future to further define the downgradient
edge of the plume. This information will be used during the
remedial design phase.
Groundwater contaminants requiring remediation include volatile
organic compounds (VOCs), iron and manganese. Total VOC con-
centrations were detected at levels as high as 620 ppb in the
onsite monitoring wells and 14 ppb in downgradient private
wells. The volatile contaminants consist primarily of the
dichloroethene (DCE) and dichloroethane (DCA) compounds. 1,2-
DCA is the most widespread of the VOCs.
15
-------
No municipal water supplies have been affected thus far by
site-related contaminants. 1,2-DCA was detected above the
State of California maximum contaminant level (MCL) of 0.5 ppb
in several of the downgradient private wells as far as 2,800
feet from the site. The state MCL is considered an ARAR for
site remedial action. The federal MCL drinking water standard
of 5 ppb was not exceeded in private wells. Table 4 indicates
which constituents detected in the groundwater exceeded federal
and/or state standards and action levels. These standards and
action levels are the cleanup goals for the site. Figures 5
and 6 show results from rounds l, 2 and 3 of VOC sampling.
Naturally occurring iron and manganese appear to be going into
solution and contaminating the groundwater beneath the site.
This is due to the acidic nature of the site wastes and the
reducing environment beneath the site. These contaminants were
detected at concentrations greater than secondary MCLs in three
rounds of sampling, as shown in Figures 6, 7 and 8.
In general, the pH of groundwater upgradient and downgradient
of the site is greater than it is beneath the site. The
average pH upgradient and downgradient of the site was greater
than 7.0, but beneath the site it was generally less than 7.0.
A pH of 6.0 was detected in several of the shallow onsite
wells.
The Purity Oil site is located in the northwest corner of the
Malaga County Water District and is served by District water
supplies. The private wells and municipal wells in the site
area are shown in Figure 9. The Malaga and Calwa County Water
Districts have domestic water supply wells located to the
southeast, east and northeast of the site. These wells are not
downgradient of the site and do not appear to influence
groundwater flow at the site. The depth of these municipal
wells ranges from 200 to 500 feet.
The nearest downgradient City of Fresno municipal well (Well
PW40) is located approximately one and three quarter miles
northwest of the site. Analyses conducted during October 1984
and June 1988 did not show site-related contamination in this
well. The Fresno city well is approximately 500 feet deep.
A number of properties in an area west and north of the site
(downgradient) are not supplied with municipal water. Unless
water is imported, privately owned wells are the sole source of
water in this area. Some of these wells have been affected by
contaminants from the Purity site. The majority of these
private wells are used by service-related industries, that do
not use large volumes of water for processing. Most private
wells in the vicinity of the site are screened to depths of 60
to 160 feet. An irrigation well located at the corner of North
Avenue and Cedar Avenue (Well PW39 on Figure 9) probably pumps
the most water of any of the production wells near the site.
16
-------
Table 4
Contaminants Exceeding
Groundwater Cleanup Goals*
(in parts per billion)
Compound.
Inorganics
Iron
Manganese
Maximum
Concentration Detected
1,540
2,520
Federal MCL's
Primary Secondary
300
50
State
Action L
Taste
Toxicity & Odor
State MCL's
Volatile Organics
Trichloroethylene 8
i
1,2-Dichloroethane 8
l ,l-Dichloroethane 53
1,1-Dichloroethene 12
Benzene 16.9
Vinyl Chloride 3
Carbon Tetrachloride 13
Cis-l,2-DCE 220
Trans-1,2-DCE 19
5
5
7
5
2
5
70 (proposed)
100 (proposed)
6
10
5
. 5
6
1
. 6
.5
* Based on additional sampling conducted during remedial design and any changes to
action levels, information in this table is subject t;o change. Contaminants may
added or deleted or clean up goals revised.
Goals cited from "Region IX EPA Drinkj
Drinking Water Branch. June. 1989).
Water Standards and Health Advisory
standards/
need to be
(EPA.
-------
: too o too 440 rtiT ' *
' | ««f'^»il^««
-------
ONI* out ro p
NO N..t nr ircitn
OROUNDWATER SAMPLING RESULTS
ROUND 3. JUNE 1980
VOLATILE3. SEMIVOLATILC8.
IRON AND MANGANESE
V OH S*tiS »tU
KO. CAlttOANIA
-------
'U
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1
MONTH AVCNUC
inzza 'B
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W^N '4''''>"v^-vy': ~'! ;-f " .'"T'fe ';i!^' -4"'K.-
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UNllT Oil. B»HS Bill
MI3NO. CAtirONNi*
-------
NORTH AVINUB
ROUNDS I AND 2
CONCENTRATIONS OF MANGANESE
-------
or CITY or FRESNO WAtER LINES
A
10
AAA
1000
AAA
17 16 15
1000 FEET
LEGEND
A PRIVATE WELLS
• MUNICIPAL WEi.l S
32
34A
k35
36A
9A
36BA £
36CA 37
APPRO*. BOUNOAHY OF CALWA COUNTY WAIEB OISIBICT
- GROUNDWATER
INVESTIGATION AREA
OF HAIAOA COUNTY
WATER DISTRICT
II'
FIGURE 9
OFFSITE GROUNDWATER
INVESTIGATION AREA AND
LOCATIONS OF PRIVATE
AND MUNICIPAL WELLS
REMEDIAL INVESTIGATION REPORT
PURITY OIL SALES SITE
FRESNO. CALIFORNIA
-------
No exceedances of federal or state ambient air quality stan-
dards for site related constituents were detected at the Purity
site as long as the surface of the site remained undisturbed.
When surface-waste seeps were disturbed or subsurface wastes
were exposed, elevated levels of atmospheric contaminants were
emitted. The contaminants emitted when wastes were exposed in-
cluded compounds such as benzene and sulfer dioxide which could
result in potential adverse health effects. Additional air
quality analysis will be conducted for the soils operable unit
remedy.
VI. RISK AS-SF.SSMFMT SUMMARY
A baseline risk assessment was prepared for the Purity site
that identified and evaluated potential human health and en-
vironmental threats if no remedial action were taken.
CHEMICALS OF CONCERN
The contamination at Purity consists mainly of volatile
chlorinated hydrocarbons. Semivolatile organics, pesticides,
and high levels of metals have also been detected. The par-
ticular chemicals of concern identified in the risk assessment
are listed in Table 5. The toxicity profiles of the chemicals
of concern are included in the Public Health Evaluation (CH2M
Hill, 1989).
Acute toxic effects of 1,2-Dichloroethane, the primary
groundwater contaminant include central nervous system depres-
sion, lung irritation, and injury to liver, kidney and
adrenals. Deaths in humans exposed to high levels of 1,2-DCA
by ingestion or inhalation may result from circulatory and
respiratory failure. Chronic exposure can cause liver
degeneration and kidney damage in laboratory animals. Eye
damage has been observed in dogs injected with 1,2-DCA.
Repeated exposures have been associated with anorexia, nausea,
liver and kidney dysfunction and neurological disorders in
workers. 1,2-DCA is carcinogenic in mice and rats exposed
orally. It is mutagenic in some tests in bacteria, barley and
fruit flies.
EXPOSURE PATHWAYS
The exposure pathways of concern that were evaluated for poten-
tial health risks can be divided into four major categories:
o Contaminated groundwater use by downgradient residents or
workers (both current and future)
23
-------
Table 5
CONTAMINANTS OF CONCERN AT THE
PURITY OIL SITE
Mercury
4-Methyl-2-pentanone
2-Methyl phenol
4-Methyl phenol
Napthalene
N-nitrosodiphenylamine
PAHs?
PCBs15
Pheno1
Selenium
Silver
Styrene
Tetrachloroethene
Toluene
1,1,1-Trichloroethane
1,1,2-Trichloroethane
Trichloroethene
Vanadium
Vinyl chloride
Xylenes
Zinc
Acetone
Aldrin
Antimony
Arsenic
Barium
Benzene
Benzoic acid
Beryllium
Beta-BHC
Bis (2-ethylhexyl) phthalate
2-Butanone
Cadmium
Carbon disulfide
Carbon tetrachloride
Chlorobenzene
Chloroform
Chromium
Cyanide
4,4-DDD
4,4-DDE
4, 4-DDT
Di-n-butyl phthalate
l ,1-Dichloroethane
1,1-Dichloroethene
1,2-Dichloroethane
Dieldrin
Diethyl phthalate
Endosulfan
Ethylbenzene
Gamma-BHC (Lindane)
Heptachlor
Heptachlor epoxide
Lead
Methylene chloride
N-nitrosodiphenylamine
which are considered carcinogenic are assessed as a
group (Benzo[a]anthracene,~Benzo[k]fluoranthene and
Chrysene).
bPCBs are assessed as a group (Arochlor 1248, Aroclor 1254,
Aroclor 1260) .
24
-------
o Direct contact with contaminated site soils by
trespassers and future onsite workers or residents
o Direct contact with contaminated canal water and sedi-
ments by trespassers, farm workers, and irrigation dis-
trict workers
o inhalation of site dusts by current near-site residents
or workers, and future onsite residents or workers
RISK CHARACTERIZATION
From these exposure pathways, the following conclusions were
reached regarding potential health issues:
o For adults and children exposed to noncarcinogens in
the groundwater, the reference dose (the exposure level
that would not be expected to cause adverse effects
when exposure occurs for a significant portion of the
life-span) is not exceeded for any contaminant.
o For residential and occupational groundwater users, ex-
cess cancer risks ranged from 8 x 1Q to 4 x 10 for
the worst-case exposure and 2 x 10 8 to 8 x 10~5 for
the most probable exposure. (EPA selects site remedies
from within a 10~4 to 10 risk range, with a general
goal of achieving a 10 level of protection).
o For adult and child residents, and occupational
workers, direct contact with surface soils, canal sedi-
ments and buried wastes exceeds the reference dose for
lead under the worst-case exposure scenario.
o For residential and occupational exposure to these con-
taminated soils, the excess cancer risks range from l x
10~g to 7 x 10_ for the worst-case exposure, and 6 x
10~8 to 4 x 10~6 for the most probable exposure.
o For residential and occupational site users, no
reference dose was exceeded for exposure to noncar-
cinogens via inhalation. Adult residential exposure
cancer risks ranged from 2_x 10~9 to 2 x 10 for the
worst case, and from 3 x 10"1 to 4 x 10 for most
probable case. For occupational exposure the cancer
risk ranged from 8 x 10" to 4 x 1Q~ for the worst
case, and from 8 x 10 ** to 6 x 10 for the most prob-
able case.
The two major public health concerns associated with the no-
action alternative are the presence of a complete groundwater
exposure pathway which could bring residents or local workers
into contact with contaminants released from the site; and
25
-------
-the potential for adverse health effects if people
(especially children) come into contact with lead-
contaminated onsite soil and canal sediment.
VII. CHANGES TO THE PROPOSED PLAN
The Proposed Plan for groundwater was for a seven extraction
well system capable of pumping 700 gallons per minute (gpm).
The intent of the original plan was to aggressively cleanup
the plume area that exceeded the federal MCL of 5 ppb for
1,2-DCA, and contain the plume area that had lower con-
taminant concentrations.
The remedy selected for this ROD is a 10 extraction well sys-
tem capable of pumping 1,450 gpm. This change was made be-
cause the state recently promulgated an enforceable MCL stan-
dard for 1,2 DCA of .5 ppb which was identified as an ARAR
for the site. In order to meet this ARAR, the plume area re-
quiring cleanup was expanded. The selected remedy will be
the most cost-effective and efficient alternative in meeting
ARARs and protecting public health.
The Proposed Plan for soils involved treatment of 55,000
cubic yards of soil followed by redisposal onsite and cap-
ping. The specific treatment method to be used was to be
based on the results of treatability studies. Due to policy
and guidance developments that encourage completion of
treatability studies prior to remedy selection, remedy selec-
tion for the Purity site soils will not be made in this ROD.
Treatability studies are currently being initiated. Results
should be available in mid-1990, after which time a soils ROD
will be prepared. Additional opportunity for public comment
and review of treatability study data will be provided prior
to issuance of the soils ROD.
VIII. GROUNDWATER ALTERNATIVES
The following section briefly describes the alternatives that
were considered for groundwater cleanup. Alternative W3 is
the selected remedy.
The groundwater alternatives are described in the Feasibility
Study in terms of two general areas of contamination: 1) the
groundwater beneath and immediately downgradient of the site
(defined as the MCL target area), and 2) groundwater in the
MCL area plus groundwater in the private well area extending
approximately 800 feet north of North Avenue (defined as the
State action level (SAL) area). These areas are depicted in
Figure 10. This definition of target areas was originally
designed before the state action level for 1,2-DCA was re-
placed by a state MCL. Therefore, these two areas will now
be described as the federal MCL area and the state MCL area.
26
-------
FIGURE 10
PROPOSED
CLEANUP TARGET AREAS
FEASIBILITY STUDY REPORT
PURITY OIL SALES SITE
. FRESNO. CALIFORNIA
GETfVREA
AlEA)
MCL ° MAXIH )M CONTAMINANT LEVEL
V
. -
- ' XL. A
•U-V*. -^^i
j • f;. »- * . ^ J • * . • -. • » . •* \i
JJL.-JL —•»«-^--'"' •»-'' ..^'^jft
* •••f-^- »
-------
ALTERNATIVE Wl — NO ACTION
The existing groundwater conditions would not be remediated.
This alternative is used as a baseline for comparison to
other alternatives and would have the same health effects as
those described in the Public Health Evaluation. The cost
for this alternative would be zero.
ALTERNATIVES W2 and W3 — GRQUNDWATER EXTRACTION: ONSITE TREAT -
DISPOSAL
Remedial actions under both Alternatives W2 and W3 would in-
clude the following:
o Groundwater extraction
o Onsite treatment
o Disposal of treated water
o Alternate water supply
o Institutional controls
Under alternative W2 , it is estimated that six extraction
wells would pump 450 gpm of groundwater from the federal MCL
area to the site, for removal of organic contaminants, iron
and manganese. For W3 , it is estimated that ten wells will
pump 1,450 gpm. These pumping rates and the number of wells
where estimated for the Feasibility Study (FS) based on
available data, and could be higher or lower depending on
results of the remedial design and on existing conditions
when extraction wells are installed and tested.
Using the FS estimates, under W2 one extraction well would
pump 250 gpm, three wells would pump 50 gpm, and two wells
would pump 25 gpm. For W3 , five wells will pump 250 gpm,
three wells will pump 50 gpm and two wells will pump 25 gpm.
The approximate extraction well locations for W2 and W3 are
shown in Figures 11 and 12 respectively. The final design
criteria, pumping rates and location of the wells will be
determined during remedial design.
In both cases, treated groundwater would either be discharged
to the North Central Canal, reinjected into the groundwater
with injection wells, or discharged to offsite infiltration
basins.
Under both alternatives, the groundwater treatment processes
at the site include flow equalization, greensand, air strip-
ping and possibly vapor-phase carbon adsorption. Air strip-
ping would be used to remove all of the volatile organic com-
pounds (VOCs) detected at the site. A vapor-phase granular
activated carbon system would be used to remove VOCs released
28
-------
FWUHE 11
PROPOSED EXTRACTION WELLS
AND PREDICTED ZONES OF
CAPTURE FOR W2
FEASIBILITY STUDY REPORT
PURITY OIL SALES SITE
FRESNO, CALIFORNIA
"1
*»—
»
1
•><5- k
-------
FIGURE 12
PROPOSED EXTRACTION WELLS
AND PREDICTED ZONES OF
CAPTURE FOR W3
FEASIBILITY STUDY REPORT
PURITY OIL SALES SITE
FRESNO. CALIFORNIA
"1
1
I FLOW PATHS*
ZOMES OF CAPTURE FOR
».. EX.TKACTION WELLS
> \
LINIS OF EQUAL
QROUNOWATER ELEVATION
-------
in the stripping tower, if needed to meet emissions require-
ments. A flow diagram of the treatment process is shown in
Figure 13. Groundwater extraction and treatment might con-
tinue for 10 to 20 years, under both options.
The greensand filtration process would be used to remove iron
and manganese. This process removes iron and manganese by
adding potassium permanganate that oxidizes the soluble iron
and manganese to an insoluble state and removes the
precipitate by filtration. A downflow pressure filter would
be used. Based on a conceptual evaluation of the system,
three filters may be required for Alternative W2. Each fil-
ter would have a diameter of 7 feet and would be 10 feet
high. For W3, two rectangular filters would be required,
each 8 feet by 20 feet and would be 10 feet high. In both
cases, the filter beds would be 5 to 6 feet deep. The fil-
ters would be backwashed once per week at arate of 15 gpm for
W2 and 45 gpm for W3. The backwash water would be discharged
to a public waste water treatment plant, disposed of offsite
or placed in onsite evaporation basins.
The air stripping tower for W2 would have a diameter of 5
feet and a packing height of 12 feet. For W3 , the tower
diameter would be 10 feet with a packing height of 16 feet.
Only one unit would be required in each case. The loading
rate on the stripping tower would be approximately two pounds
of VOCs per day for W2 and 8 pounds for W3. The air from the
stripping tower may be discharged to a vapor-phase carbon ad-
sorption unit, for capture of the VOCs. For W2, one carbon
adsorption unit having a 10-foot diameter would be required.
The unit would require 17,600 pounds of carbon each year.
For W3, three units, each having a 10-foot diameter, would be
required and would use 64,300 pounds of carbon per year.The
carbon unit would be used if necessary to meet air quality
standards and the EPA air stripper policy.
The need for carbon filtration will be determined based on
additional ambient air quality and meteorological data
gathered during design, and subsequent modelling efforts. If
needed, the carbon system would be designed for temporary use
at startup until meteorological and emission conditions can
be monitored. Coordination with the EPA Air Management Divi-
sion and the Fresno Air Pollution Control District will take
place on this issue.
These groundwater treatment processes do not remove phenol.
State action levels for phenol are based on aesthetics and
are established for the purpose of controlling taste and odor
in chlorinated water supplies. Existing groundwater data in-
dicate the possible presence of phenol, but the data are in-
conclusive as to the existence, extent and source of the con-
tamination. Removal of phenol would require that a liquid-
31
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BACKWASH
i WAS IF WATER
(TO M)TW OR
LANDFILL)
CROUNOWATFH
((ROM WELLS)
I
I
~-/\ r\
fff*>
ING
$•
— DISTRIBUTOR
AIR STRIPPING
COLUMN
1
AIR
DISCHARGE
VAPOR
PHASE
CAC. IF
NECESSARY
1
BLOWER
HEATER
EQUALIZATION
TANK
BACKWASH
SUPPLY
.1
r
TREATED
WATER
(MCL'S)
AQUEOUS
PHASE CAC
(POLISHING)
FOR PHENOL
REMOVAL. IF
NECESSARY
I
I
TREATED
WATER
(SAL'S)
FIGURE 13
WATER TREATMENT
PROCESS DIAGRAM
HIHHi.VV.'O HI
on SAU;S sin
(HI SNO. CAIirORNIA
-------
phase activated carbon process be added to the alternatives.
Further groundwater sampling will be performed to better
define the extent of the phenol contamination before includ-
ing the activated carbon in the groundvater treatment
process. Removal of phenol from the treated water may be
needed to meet state Waste Discharge Requirements, depending
on the final disposal option selected. The cost of adding an
activated carbon process to remove phenol was included in the
cost sensitivity analysis in Chapter 4 of the Feasibility
Study.
The treated groundwater would either be discharged to the
North Central Canal at a location adjacent to the site, rein-
jected into the groundwater by injection wells, or discharged
to infiltration basins. Discharge to the North Central Canal
would require construction of a short outfall pipe to the
canal. Reinjection of the groundwater would require ap-
proximately four reinjection wells for Alternative W2 and 10
wells for W3. The depths of the wells would be approximately
100 feet, or deeper. The exact location, number and pumping
rates of the wells will be determined during remedial design.
Discharge to infiltration basins would require approximately
7 acres of land for W2 and 23 acres for W3. Sufficient land
is available within approximately 0.5 to 1 mile of the site
for construction of the infiltration basins. The specific
disposal option(s) selected will be based on technical,
regulatory and cost criteria and will be made in consultation
with state and local agencies. As part of the disposal of
treated water, recharge to the local aquifer will be maxi-
mized as much as possible.
For both W2 and W3, an alternate water supply would be
provided for the water users located in the area northwest of
the site, east of Highway 99, and south of North Avenue. The
Malaga County Water District serves the area immediately
north of the Purity Oil site, and connection to its system
would be technically feasible. Use of individual carbon
filtration systems for each well and bottled water would also
be investigated, in lieu of an underground water pipe system.
Groundwater monitoring and institutional controls would be
implemented for either alternative. Approximately three ad-
ditional monitoring wells would be installed in the vicinity
of the site for W2 and 12 for W3. The exact location of the
wells would be established during"remedial design. Ap-
proximately 20 monitoring wells would be sampled quarterly
for indicator constituents for W2 and 40 for W3, with a more
extensive suite of contaminants tested for annually. A
groundwater management zone would be created to control pump-
ing to maintain groundwater levels at the desired configura-
tion. Creation of the groundwater management zone will be
one of the first tasks during remedial design. Prior to in-
itiation of remedial action, the management zone must be in
place to ensure that the remedial action will be effective.
33
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IMPLEMENTATION ELEMENTS FOR ALTERNATIVE W3
The following discussion provides more detailed information
on project elements for the selected alternative, W3, that
were briefly described in the previous sections.
Monitoring Requirements for W3
When remedial design begins, 1- to 2-week pilot pumping tests
will be conducted on several of the monitoring and/or private
wells. Based on these tests, the number, locations, and
pumping rates of the extraction wells will be selected.
The effectiveness of the remedial action in creating a
hydraulic zone of capture will be demonstrated by monitoring
the water levels in strategically located wells. The exist-
ing monitoring wells and private wells may assist in defining
the hydraulic zone of capture, but it will be necessary to
construct additional wells to demonstrate the system's effec-
tiveness .
After the new monitoring wells have been installed, monitor-
ing of the groundwater quality and hydraulic capture zone
will be necessary. If the data show that the hydraulic cap-
ture zone is insufficient, additional extraction wells may
have to be installed or the pumping rates adjusted. Also,
prior to implementing the extraction alternative, additional
monitoring wells will be installed near the private wells
north of North Avenue to better define the extent of con-
tamination in this area.
It is difficult to forecast the total number of additional
monitoring wells that win be required for monitoring the ex-
traction well field. For the purpose of estimating costs, it
was assumed that a total of 12 additional monitoring wells
will be required for W3. Some of the 12 monitoring wells
might be installed as part of the planned additional inves-
tigation of the downgradient extent of the plume.
Potential locations for these monitoring wells are shown in
Figure 14. The monitoring well locations will be chosen at
critical points to allow monitoring of the hydraulic gradient
toward the well field and to determine if contaminants be-
tween wells are migrating toward" the wells. The likely areas
for the development of stagnation points are between the ex-
traction wells. The long-term operation of the well field
will likely be based on maintaining the hydraulic gradient
toward the well field.
Groundwater levels will be monitored frequently, at least
weekly during startup and monthly thereafter. At least 60
wells will be monitored for groundwater levels under W3.
Groundwater quality can be monitored less frequently. For
the purpose of estimating costs, it is assumed that indicator
34
-------
FIGURE u
POSSIBLE MONITORING WELL
LOCATIONS
FEASIBILITY STUDY REPOMT
PURITY OIL SALES SITE
FRESNO. CALIFORNIA
J
-------
constituents win be analyzed quarterly, with a more exten-
sive suite of constituents analyzed annually. It was assumed
that 40 wells win be monitored for water quality under W3.
The extraction wells can be shut off sequentially if the
monitoring data indicate that levels of contamination have
been reduced to below the cleanup goals. Monitoring should
be performed at least one year after the system is shut off
to see if contaminant levels increase as a result of chang-
ing groundwater levels.
Once the offsite contamination has been reduced to levels es-
tablished by EPA and the state, an assessment will be made to
determine if the site is still a source of groundwater con-
tamination. This will require additional field investig-
ations including groundwater and soil sampling. If the site
continues to be a source of groundwater contamination, a
source control pumping alternative will be implemented until
the concentration of contaminants discharging from the site
is reduced to levels established by EPA and the state.
However, remediation of site soils should prevent this from
happening.
Coordination Requirements for W3
The groundwater cleanup will involve management of the
groundwater levels to allow collection of contaminants and
flushing of the aquifer. A properly controlled and monitored
system of wells can effectively contain contaminants.
However, if uncontrolled pumping of nearby large wells (such
as the irrigation well) were allowed to occur, the effective-
ness of the remedial actions may be seriously reduced.
Therefore, management of groundwater levels must include
provisions for managing and controlling the groundwater con-
ditions in the nearby area. This may include creation of a
groundwater management zone that would extend some distance
(1 to 2 miles) from the cleanup area. Within such a manage-
ment zone, pumping would be controlled to maintain
groundwater levels at the desired configuration. Such con-
trol would include large municipal and private wells in addi-
tion to aquifer remediation wells that may be installed at
other nearby hazardous waste sites. It will also be impor-
tant to coordinate disposal of the discharge water with the
local water agencies both before and during project implemen-
tation.
Groundwater Disposal Alternatives for W3
Three alternatives have been identified for disposing of
treated groundwater from the Purity Oil site: 1) discharge
to the Fresno Irrigation District's (FID) canal located ad-
jacent to the site, 2) discharge to infiltration basins, and
3) reinjection of treated groundwater into the same aquifer
it is being extracted from. Each alternative has different
implementation requirements and costs.
36
-------
Extraction of the groundwater for W3 will require disposal cf
approximately 1,450 gpm of treated groundwater. The three
groundwater disposal alternatives are discussed below.
1. Disposal in North Central Canal
In this disposal alternative, the groundwater would be
treated and discharged to the North Central Canal at a loca-
tion near the Purity site. From the Purity site, the canal
flows in a westerly direction for approximately 5 miles
before discharging into the Central Canal. The Central Canal
eventually dead-ends approximately 10 miles from the Purity
site and has no outlet to any surface drainage course.
The maximum flow in the North Central Canal during the ir-
rigation season is approximately 26 cubic feet per second
(cfs). The volume of treated groundwater discharged to the
canal would be approximately 3 cfs, resulting in a dilution
ratio of 9:1. Preliminary discussions with the FID indicate
that they preferred the canal to be dry during nonirrigation
months (generally November through February) to reduce weed
and algae growth and allow for maintenance of the canal.
However, maintenance of the canal might still be possible if
treated groundwater is discharged to the canal during the
nonirrigation season. Additional discussion with the FID will
be needed to address canal maintenance.
An infiltration test was performed in the canal prior to the
1988 irrigation season as part of the remedial investigation.
The test results indicated the infiltration rate is 0.038
gpm/foot of canal length or less, adjacent to the site.
Based on an infiltration rate of 0.038 gpm and a groundwater
discharge rate of 1,450 gpm (W3), it is likely that all of
the treated groundwater would infiltrate into the North
Central Canal and the Central Canal during the nonirrigation
season. During the irrigation season the treated groundwater
would be used to irrigate cropland. Prior to implementing
this alternative, the California Regional Water Quality Con-
trol Board will issue Waste Discharge Requirements which
would specify the quality of water that can be placed in the
canal and would include monitoring requirements.
2. Disposal in Infiltration Basins
In this alternative, the treated groundwater would be dis-
charged to infiltration basins located in the site vicinity,
managed by the Fresno Metropolitan Flood Control District.
In the Fresno area, approximately 70 to 100 feet of water per
year can be delivered to infiltration basins. Based on
groundwater extraction and a treatment rate of 1,450 gpm, 20
acres of land would be required for this alternative. The
infiltration area would be divided into two separate basins
to permit periodic maintenance. Excavation to approximately
4 feet would provide capacity for all the treated water and
some freeboard.
37
-------
Treated groundwater would be pumped from the treatment
facilities to the infiltration basins. Under the above ex-
traction rate, the land requirements would dictate that the
infiltration basins be located on agricultural land away from
the site. Land may be available through the Fresno
Metropolitan Flood Control District, within approximately 1
mile both west and south of the site. A pipeline would be
constructed from the site to the basin. Waste Discharge Re-
quirements, including monitoring provisions, would be re-
quired from the RWQCB. Coordination with the Flood Control
District regarding their concerns and requirements would be
needed during the design phase.
3. Disposal in Injection Wells
In this alternative treated groundwater would be injected
into the same aquifer from which it was extracted. For pur-
poses of the Feasibility Study, it was assumed that the wells
would be within 1,000 feet of the site to minimize piping
costs. No specific locations were identified. Injection
well placement would need to be designed to not adversely af-
fect, and possibly to enhance, the zone of capture for the
extraction well system. If reinjection is selected as a
groundwater disposal option, the size and location of the
wells will need to be determined during remedial design.
Based on groundwater extraction and treatment at a rate of
1,450 gpm, it was estimated that up to 10 .injection wells
would be needed. The injection wells would be gravel packed
and screened in a manner similar to a domestic water supply
well. The diameter of the injection wells would be at least
12 inches, and the depth of the wells would be approximately
100 feet or deeper. The quality of the reinjected water
would have to meet federal and state drinking water stan-
dards. Reinjection wells would need to comply with the
RWQCB's Waste Discharge Requirements, consistent with the
Basin Plan water quality objectives.
IX. TANK REMOVAL ALTERNATIVES
In the Feasibility Study, two alternatives were presented for
tank cleanup. In one alternative, the contaminated wastes in
the seven onsite steel tanks would be removed from the tanks
and transported to a RCRA landfill for disposal. The waste
would be removed using a backhoe or a crane with a bucket and
placed in 55-gallon drums. Solidification of a portion of
the wastes may be necessary. The seven tanks would be
scraped by hand to remove any remaining loose, tarry sludge.
The asbestos coating on Tank 5 would be removed and packaged
for offsite disposal. The steel tanks would be dismantled
and transported to an approved offsite landfill or scrap
yard. This is the selected remedy for tank cleanup.
38
-------
In the other alternative, if site soils were going to be
treated or contained on-site, the contaminated wastes in the
tanks would be removed, stored onsite in drums and treated or
contained with contaminated soils. The seven tanks would
then be handled as in the 1st alternative.
Since a soil remedy is not being'selected in this ROD, the
tank wastes will be disposed of at an appropriate off-site
facility rather than be drummed on-site. This will avoid on-
site storage of hazardous waste until remediation of site
soils is undertaken.
X. ARARS ANALYSIS
A detailed analysis and discussion of the identified ARARs
for the groundwater and tank alternatives is presented in
Table 6. It should be noted that for the most part only the
substantive requirements of ARAR-s apply to onsite actions and
onsite is defined to be the areal extent of contamination and
all suitable areas in reasonable proximity to the contamina-
tion necessary for implementation of the response action,
rather than the legal property boundaries of the site.
XI. COMPARATIVE ANALYSIS OF ALTERNATIVES
This section of the ROD evaluates the performance of the al-
ternatives in relation to: short-term effectiveness; long-
term effectiveness; reduction of toxicity, mobility and
volume; implementability; ARARs; cost; overall protection of
public health, and; state and community acceptance. The pur-
pose of this comparative analysis is to identify the ad-
vantages and disadvantages of each alternative relative to
one another to identify key tradeoffs.
SHORT-TERM EFFECTIVENESS
Alternatives W2 and W3 would provide similar protection to
the community and the workers during construction. Alterna-
tive W2 would require approximately 20 months to construct,
and Alternative W3 would require approximately 24 months.
Each of the alternatives would require groundwater treatment
for approximately 10 to 20 years.
Alternatives W2 and W3 would have_similar minor short-term
environmental impacts which could" be mitigated. These im-
pacts entail noise, dust and traffic disruption commonly as-
sociated with similar construction projects. These impacts
would not be significant and could be mitigated to minimize
disruption.
The short-term construction impacts of tank removal would be
similar whether the wastes were stored on-site or disposed of
offsite. Short-term impacts of off-site disposal include
39
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Table 6
ARARs ANALYSIS
GROUNDWATER ALTERNATIVES AND TANK REMOVAL
R EMO VAL — GROUNOWATER
Extraction
Action
I. Cal. Water Code
O §§ 13750-13755
II. Fresno County Well
Construction Ordinance
o 470-A-39
i
III. Safe Drinking Water
Act (SDWA)
o 42 U.S.C. § 300(f)
et seg
O 40 C.F.R. § 142
IV. California Safe Drinking
Water Act
o Cal. Health and Safety
code § 4010-4037
o Cal. Admin. Code,
title 22 §§ 64401 e_t sea
V. Department of Health
Services (DHS) Action
r.ovei.s for Public Drinking
.•;.I'
-------
Table 6
(Continued)
TREATMENT—GROUNDWATER
Air Stripping
Action
I. Resource Conservation
and Recovery Act as
amended (RCRA)
O 42 U.S.C. § 9601 fit seq
o 52 FR 3748 (Feb 5, 1987)
II. Clean Air Act (CAA)
O 42 U.S.C. SS 7401-7642
O 40 C.F.R. SS 50-99
o CAA § 101
Comments
The proposed standard for VO emissions from "product
accumulator vessels" and leak detection programs, if
finalized, will be relevant and appropriate to certain air
stripping processes. This proposed standard is currently to
be considered.
The substantive provisions of these regulations may be appli-
cable to the air stripping tower. These regulations cover
design standards, permitting requirements, modelling, control
technology, air quality standards and hazardous constituents.
III. Mulford-Carrell Air
Resources Act (CARA)
o Cal. Health & Safety
Code SS 3900-44563 '
o Fresno County Air
Pollution Control
District, Regulation
IV Prohibitory Rules
CARA meets the requirements of the federal CAA for state
primacy. CARA is regulated by the Air Resources Board and
enforced by the Fresno Air Pollution Control District.
In addition, CARA establishes specific requirements, some
of which are more stringent than the federal standards
for a number of pollutant sources including toxic air con-
taminants. These regulations may be applicable to the
air stripping tower.
Carbon Adsorption and Greensand--ARARs pertain to management and disposal of wastes generated in
carbon and greensand processes.
Action
I. Resource Conservation and
Recovery Act (as amended)
(RCRA)
O 42 U.S.C. § 6901
et seq
O 40 C.F.R. §§ 261, 263,
264
Comments
If carbon or greensand wastes are taken offsite or managed
onsite, RCRA requirements would be applicable if these wastes
are designated as RCRA hazardous wastes. These regulations
govern identification, generation, transport and disposal
of hazardous waste.
41
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TREATMENT--GROUNDWATER
Table 6
(Continued)
Carbon Adsorption and Greensand (Continued)
Action
II. (California) Hazardous
Waste Control Act (HWCA)
o Cal. Health & Safety Code
§§ 25100-25395
o Cal. Admin. Code title 22,
Chapter 30
III. (California) Porter-
Cologne Water Quality
Control Act
o Cal Water Code § 13240
o Cal. Admin. Code, title 23,
§ 2520
IV. Clean Water Act (CWA)
O 33 U.S.C. §§ 1251-13')6
o 40 C.F.R. § 403
Comments
The HWCA defines and controls hazardous wastes from generation
to disposal. More stringent state regulations would be
applicable to carbon or greensand wastes if they are state
hazardous wastes.
The water quality objectives in the Basin Plan may be
applicable to discharges (e.g., backwash water) from the
greensand treatment process. Subchapter 15 requirements
of title 23 are to be considered.
For disposal to a POTW, the NPDES pretreatment requirements
of the CWA may apply. NPDES requirements are administered
under the Porter Cologne Act. The POTW would issue a permit
for this discharge.
DISPOSAL--GROUNDWATER
Reinjection
Action
I. Safe Drinking Water Act
(SDWA)
o 42 U.S.C. § 300(f) e_t sea
O 40 C.F.R. §§ 144, 146
Comments
EPA administers the program for Class I, III, IV, and V wells
in California. Reinjection at the Purity site would
constitute a Class V well, which currently is not covered
under the UIC permitting program but is subject to the
inventory provision of the UIC program. The inventory
requirement is relevant and appropriate due to the technical
value of the report information. The construction, operation
and maintenance requirements for UIC wells are to be con-
s idered.
42
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DISPOSAL—GROUNDWATER
Table 6
(Continued)
II.
Ill
IV.
V.
VI.
Action
Cal. Water Code
O §§ 13750-13755
Fresno County Ordinance
o 470-A-39
Safe Drinking Water Act
(SDWA)
O 42 U.S.C. 300(f) fit seg
O 40 C.F.R. § 142
Department of Health
(DHS) Action Levels for
Public Drinking Water
Supplies (January 1987)
Comments
The reporting requirement concerning well construction would
be relevant and appropriate as it is one of the state's
mechanisms for protection of water quality. Reports concern-
ing construction, alteration or destruction of wells are filed
with the Department of Water Resources.
This ordinance regulates the construction, alteration and
abandonment of wells in Fresno County. The ordinance, being
derived under state law, is applicable as a mechanism for
protection of water quality.
The primary maximum contaminant levels (MCLs) of the SDWA are
relevant and appropriate where groundwater may be a potential
source of drinking water, whether or not it is considered a
"community" supply. Federal MCLs would be relevant and
appropriate requirements for reinjected water.
Health-based numeric guidelines set by DHS for the protection
of public drinking water supplies through nonpromulgated
standards are the levels at which DHS requires water
purveyors to take corrective action. These guidelines are
to be considered.
California Safe Drinking This Act provides for primacy of California with Federal SDWA
Water Act and requires California to set maximum contaminant levels
o Cal. Health and Safety Code equal to or more stringent than Federal. California MCL's
§§ 4010-4037 relevant and appropriate requirements.
o Cal. Admin. Code, title 22
§§ 64401 et sea
are
43
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DISPOSAL—GROUNDWATER
Reiniection (Continued)
Table 6
(Continued)
VII California Porter-
Cologne Water Quality
Control Act
o Cal. Water Code § 13240
Requirements of the RWQCB Basin Plan 5(d) are applicable to
reinjected water. Substantive and/or administrative requir-
ments may apply depending on whether the wells are on or off-
site.
North Central Canal/Infiltration Basin--Discharges of treated water to the North Central
Canal or an infiltration basin would be required to meet the substantive and administrative
requirements of applicable regulations.
Action
California Porter-
Cologne Water Quality
Control Act
o Cal. Water Code § 13260
ALTERNATIVE DRINKING WATER SOURCE
Public Drinking Water Supply
Action
I. Safe Drinking Water Act
(SDWA)
O 42 U.S.C. §300 (f) ££
o 40 C.F.R. §142
II. Department of Health
Services (DHS) Action
Levels for Public
Drinking Water Supplies
(January 1987)
Comments
The North Central Canal is located in the Central Valley
RWQCB Basin Planing Area 5(D). Requirements of that
Water Quality Control Plan are applicable to discharges
from the treatment system and would be regulated by the
RWQCB through Waste Discharge Requirements.
Comments
The primary maximum contaminant levels (MCLs) of the SDWA are
applicable requirements.
Health-based numeric guidelines set by DHS for the protection
of public drinking water supplies through nonpromulgated
standards are the level at which DHS requires water purveyors
to take corrective action. These guidelines are to be
considered.
44
-------
Table 6
(continued)
ALTERNATIVE DRINKING WATER SOURCE
Public Drinking Water Supply (Continued)
Action
Comments
III. California Safe Drinking This Act Provides for primacy of California with Federal SDWA
Water Act and requires California to set maximum contaminant levels
o Cal. Health and Safety Code equal to or more stringent than Federal. These requirements
§§ 4010-4037 are applicable.
o Cal. Admin. Code, title 22
S 66401 fit seq
INSTITUTIONAL CONTROLS
Monitoring Wells
Action
I. Cal. Water Code
O SS 13750-13755
II. Fresno County Ordinance
O 470-A-39
REMOVAL—TANKS
Action
I. Resource Conservation
and Recovery Act, as
amended (RCRA)
o 42 U.S.C. § 6901 e_t sea
O 40 C.F.R. §§ 261, 263
264, 268
Comments
The reporting requirement concerning well construction would
be relevant and appropriate as it is one of the State's
mechanisms for protection of water quality.
The ordinance regulates the construction, alteration and
abandonment of wells in Fresno County. The ordinance, which
is derived under the Cal. Water Code, is applicable as a
mechanism for protection of water quality.
Comments
If wastes are taken offsite or managed onsite RCRA require-
ments would be applicable, if wastes were RCRA hazardous
wastes. Land disposal restrictions for TCLP are unknown at
this time but may impact disposal. These requirements aovern
identification, generation, transport and disposal of hazard-
ous wastes.
45
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Table 6
(Continued)
REMOVAL—TANKS (Continued)
Action
II. Mulford-Carrell Air
Resources Act (CARA)
o Cal. Health & Safety
Code §§ 3900-44563
o Fresno County Air
Pollution Control
District, Regulation
IV Prohibitory Rules
Commentg
CARA meets the requirements of the federal CAA for state
primacy. In addition, CARA establishes specific requirements,
some of which are more stringent than the federal standards,
for toxic air contaminants. These regulations are aplicable.
Before tank removal the Fresno Air Pollution Control District
should be contacted regarding whether any actions related
to the tank removal would fall under any federal or state
air quality regulations.
III. (California) Hazardous The HWCA defines and controls hazardous wastes from genera-
Waste Control Act (HWCA) tion to disposal. The Act provides no RCRA-type exemption
o Cal. Health and Safety Code for CERCLA sites. Therefore, more stringent regulations
§§ 25100-25395 would be applicable to tank removal actions.
o 22 CCR Chapter 30
GENERAL ACTIONS
i
Occupational Safety and
Health Administration
(OSHA)
o 19 C.F.R. § 1910
OSHA requiiements are applicable to worker exposures during
response actions at CERCLA sites, except in states that
enforce equivalent or more stringent requirements. Cali-
fornia no longer has such a program for nongovernment
employee workplace exposures.
46
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potential transportation hazards. Short-term impacts of on-
site storage would be due to any accidential release or pos-
sible exposure to trespassers.
LONG-TERM EFFECTIVENESS
In Alternative W2, only groundwater in the federal MCL area
would be extracted and treated to remove organics, iron and
manganese. Concentrations of 1,2-dichloroethane would continue
to exceed the state MCL. Although the manganese levels would
continue to exceed the EPA secondary MCLs in the state MCL
area, they are not an identified public health risk.
In Alternative W2, the risk from ingestion of the groundwater
in the state MCL area would be mitigated by providing an alter-
nate water supply to the currently affected private well users.
However, the untreated groundwater in the state MCL area would
continue to move downgradient toward currently unaffected
private and municipal wells. In Alternative W3, the
groundwater in the state MCL area would be extracted and
treated for removal of volatile organic compounds, iron and
manganese. The future risk to downgradient water users would
be controlled. In Alternative W3, the water users in the state
MCL area would also be supplied with an alternate water source
until remediation is achieved.
The types of long-term controls would be similar for Alterna-
tives W2 and W3 and would include continued operation of the
groundwater treatment facilities, monitoring of the groundwater
and creation of a groundwater management zone to control pump-
ing. Alternative W2 would require periodic sampling of ap-
proximately 20 monitoring wells, and Alternative W3 would re-
quire sampling of approximately 40 monitoring wells. The need
for long-term institutional controls would be greater under W2,
since use of the unremediated portions of the plume would have
to be controlled to prevent exposure.
Both of the tank removal alternatives provide an effective
long-term solution to the tank problem. Due to the relatively
small volume of wastes (121.3 cy) an off-site disposal facility
could effectively manage these wastes. Consolidation of these
wastes with on-site soils would also be an effective long-term
solution.
REDUCTION OF TOXICITY. MOBILITY OR VOLUME
In Alternative W2, 450 gpm of groundwater would be extracted
from the federal MCL area and treated. In Alternative W3,
1,450 gpm of groundwater from the entire plume area would be
extracted and treated. The treatment facilities for each al-
ternative would remove approximately 99 percent of the organics
and 90 percent of the iron and manganese.
47
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Alternative W2 would reduce the toxicity, mobility or volume of
contaminants in the groundwater where concentrations exceed the
federal MCLs. Alternative W2 would not affect the toxicity,
mobility or volume of the contaminants beyond the federal MCL
area, where concentrations exceed the state MCL for 1,2-DCA.
Alternative W3 would provide a greater reduction in the
toxicity, mobility and volume of contaminants, that are
chemical-specific ARARs for the site.
For the tanks, the selected remedy, off-site disposal of waste
would not reduce the toxicity, mobility or volume (TMV) of the
contaminants. Storage on-site and eventual treatment would
achieve TMV reduction. However, this is weighted against the
risk of on-site storage of hazardous waste until treatment can
occur.
. T T Y
The technical and administrative feasibility of implementing
Alternatives W2 and W3 would be similar. Alternative W3 would
be slightly more difficult to implement because more extraction
wells and related piping would be required. The additional
wells would require additional remedial design studies and ad-
ditional construction. Since more extraction wells are re-
quired in Alternative W3 , obtaining access to private property
to install the wells and crossing the railroad right of way
would be more involved.
The technical and administrative requirements for implementing
the water disposal options would be similar for Alternatives W2
and W3 . Depending upon the disposal option selected, each al-
ternative would need to meet the same requirements. However,
the disposal options for Alternative W3 would be slightly more
difficult to implement since the volume of groundwater treated
would be larger. Services and materials would be available to
implement the disposal options for both of the alternatives.
Both tank alternatives would be feasible. On-site storage
would require compliance with substantive requirements govern-
ing proper storage of hazardous waste and off-site disposal
will require acceptance of waste by the permitted facility. If
required by land ban, the waste may need pretreatment by
solidification, prior to disposal.
COMPLIANCE WITH ARARs
Alternative W2 would not comply with all chemical-specific
ARARs. Since this alternative was developed, the State of
California has promulgated an MCL for 1,2-DCA of 0.5 ppb.
Therefore, W2 would not comply with this new drinking water
standard ARAR. Alternative W2 would also not comply with all
state action levels if they are TBC ARARs for the site. Alter-
native W3 would comply with all chemical-, location-, and
action-specific ARARs and would comply with state action
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levels, except for phenol. Both tank removal alternatives would
be designed to meet ARARs for generation, transportation and
disposal of hazardous waste.
The present worth capital, operation and maintenance cost •• f W3
($11,160,000) is approximately twice the cost of W2
($6,420,000), while the flow rate for the W3 area (1,450 gpm)
is approximately three times the W2 area (450 gpm). The O&M
costs follow the same pattern, at $3,620,000 for W2 and
$6,960,000 for W3. Cost of removing the steel tanks is es-
timated to be approximately $500,000. Offsite disposal of tank
wastes would likely be less costly than onsite storage in a
RCRA consistent manner.
OVERALL PROTECTION
Alternative W2 would provide a high degree of overall protec-
tion, but some risks would remain. Extraction and treatment of
the groundwater in the federal MCL area would address the risks
from ingestion of contaminated groundwater in that area. Con-
nection of the water users located northwest of the site to an
alternate water supply would mitigate the risks from ingestion
of the groundwater in the private wells north of the federal
MCL area. The risk of the contaminated groundwater in the
state MCL area migrating to the northwest would remain.
Alternative W3 would provide a higher degree of overall protec-
tion. Extraction and treatment of the groundwater in the state
MCL area would address the risks of ingestion of contaminated
groundwater for the entire plume area. Connection of the water
users located northwest of the site to an alternate water
supply would address the risk of ingestion of the groundwater
during implementation of the alternative. Alternative W3 would
also inhibit migration of the contaminants to the northwest.
Removal of the steel tanks, and disposal of the tank wastes
would eliminate a public health hazard and nuisance. In the
short-term greater protection will be achieved by disposing of
tank wastes off-site, rather than awaiting soil remediation for
their disposition.
STATE AND COMMUNITY ACCEPTANCE
Both the State of California Department of Health Services and
the Central Valley Regional Water Quality Control Board have
submitted letters to EPA supporting the remedies selected in
this ROD. Significant community input was not received during
the public comment period. Opposition was not raised by com-
munity members to implementation of the proposed groundwater
and tank cleanup alternatives. Concerns were raised that
whatever remedy was selected should be protective of the com-
munity, both in the short-term and long-term and that the com-
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munity should be kept informed on an ongoing basis of project
developments. Public and state comment on the Feasibility
Study and Proposed Plan are included in the Responsiveness Sum-
mary.
XII. THE SELECTED REMEDY
GROUNDWATER TREATMENT
The selected remedy (W3) for treating groundwater will use ex-
traction and air stripping to meet drinking water standards for
VOCs. Also, to meet secondary drinking water standards (taste
and odor), a filtration process known as greensand would be
used to remove iron and manganese from the water. The private
well users located northwest of the site, whose wells have been
affected, would be provided with an alternate water supply.
Institutional methods to control pumping will be implemented,
and groundwater quality will be monitored over time to ensure
that the remedy is effective. The effectiveness of this remedy
is dependent on a soil cleanup remedy to be proposed in a
forthcoming ROD.
Three different disposal options for the treated groundwater
are being considered: reinjecting the treated water into the
groundwater; discharging the water to the North Central Canal;
or pumping the treated water to nearby infiltration basins.
Coordination with state and local water agencies will take
place to ensure that the selected disposal method(s) are con-
sistent with local water management goals.
The entire clean-up operation is expected to take between 10
and 20 years to complete. The total cost would be ap-
proximately $11 million.
REMOVAL OF STEEL TANKS
The seven large, above-ground steel tanks currently on the site
will be removed. The contaminated waste in the tanks will
first be removed and disposed of at an EPA-approved hazardous
waste facility, with prior treatment by solidification, if
necessary. The tanks would then be cleaned, dismantled and
transported off-site to an approved landfill or scrapyard, as
appropriate. The total cost for this action is approximately
$500,000.
XIII. STATUTORY DETERMINATIONS
PROTECTIVENESS
The goal of the selected remedy for groundwater is to clean up
the aquifer to achieve federal and state drinking water stan-
dards and state action levels. Until cleanup is achieved,
users of private wells affected by site contaminants will b^
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provided with an alternate water supply. The air stripper will
be supplied with a carbon adsorption system, if needed, to con-
trol VOC discharges to the atmosphere. Extracted water will be
treated to meet whatever federal and state standards govern the
particular type of discharge. A monitoring network will assume
that groundwater cleanup goals are met in the long-term. There-
fore, protection of human health and the environment will be
achieved. Removal of the above-ground tanks will eliminate a
public health hazard and nuisance at the site.
It is not expected that any unacceptable short-term or cross-
media impacts will be caused by implementation of this remedy.
Dust and noise control measures would be implemented during
construction of the groundwater treatment facilities and tank
removal activities.
ENVIRONMENTAL IMPACTS
No significant environmental impacts are expected during con-
struction of this alternative. The only construction includes
the groundwater treatment facilities, monitoring and extraction
wells, associated piping, alternate water supply facilities and
tank removal. Dust control measures would be implemented
during construction. Air emissions from the groundwater treat-
ment process would be discharged through an activated carbon
process if needed, to reduce volatile organic compounds dis-
charged to the atmosphere. Reinjection of the treated water or
disposal within the extraction area would help mitigate the im-
pact of watertable drawdown.
COMPLIANCE WITH ARARS
Alternative W3 would comply with all chemical-, location-, and
action-specific ARARs identified for the site, except the SAL
for phenol. If phenol is determined to be site related, based
on additional sampling, addition of an aqueous-phase carbon ad-
sorption system may be required if the phenol SAL was con-
sidered to be an ARAR.
COST-EFFECTIVENESS
No other alternative to pumping and treating groundwater
provides long-term protectiveness. The selected remedy at
$11,160,000 is required to meet ARARs for groundwater cleanup.
USE OF PERMANENT SOLUTIONS AND ALTERNATIVE TECHNOLOGIES TO THE
MAXIMUM EXTENT PRACTICABLE
The remedy represents the maximum extent to which permanent
solutions and treatment can be practicably utilized. The
proposed air stripping/greensand system employs treatment that
will result in a permanent solution to the VOC, iron and man-
ganese groundwater problems, if used in conjunction with a soil
remedy.
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Offsite disposal of tank waste will result in the need for
long-term management at the receiving facility and would there-
fore not be considered use of a permanent solution to the maxi-
mum extent possible. However, the tank wastes constitute an
only relatively small volume (121.3 cy) of the over 100,000 cy
of site soils for which a permanent remedy is being evaluated
through treatability studies.
THE PREFERENCE FOR TREATMENT
The SARA preference for treatment is met by the greensand/air
stripping groundwater treatment alternative. VOC's, iron and
manganese would be removed from the groundwater with the goal
of restoring the aquifer to drinking water standards and action
levels. Used in conjunction with a source control remedy, this
would eliminate the principal groundwater threat at the site.
Offsite disposal of tank waste would not meet the SARA
preference for treatment. The SARA preference for treatment
for the rest of the site soils and waste will be addressed in
the future soils ROD.
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