United States Office of
Environmental Protection Emergency and
Agency Remedial Response
EPA/ROD/R09-93/097
August 1993
v°/EPA Superfund
Record of Decision:
Newmark Groundwater
Contamination, CA
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50272-101
REPORT DOCUMENTATION
PAGE
1. REPORT NO.
EPA/ROD/RO9-93/097
3. Recipient's Accession No.
THIe and Subtitle
SUPERFUND RECORD OF DECISION
Newmark Groundwater Contamination, CA
First Remedial Action
& Report Data
08/04/93
&
7. Authors)
a Performing Organization Rapt. No.
9. Performing Organization Name and Address
10 Project Task/Work Unit No.
11. Contract(C)orGrant(G)No.
(G)
12.
Sponsoring Organization Name and Address
U.S. Environmental Protection Agency
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report & Period Covered
800/800
14.
15. Supplementary Note*
PB94-964516
10. Abatract (Limit: 200 word*)
The Newmark Groundwater Contamination site is a 5-mile area of ground water
contamination in San Bernardino, California. Land use in the area is predominantly
residential and commercial, with a small amount of industrial use. The 110-square mile
aquifer, known as the Bunker Hill Basin, is bounded by the San Bernardino and San
Gabriel mountains to the north, the Crafton Hills and badlands to the southeast, and a
hydrogeologic barrier formed by the San Jacinto fault to the southwest. Water flowing
from all parts of the aquifer joins in a confined "artesian zone" before leaving the
basin, where the Santa Ana crosses the San Jacinto Fault Line. Most of the western
part of the basin is an unconfined aquifer with no substantial barriers to infiltration
from the surface. The estimated half-million residents in nearby communities use an
aquitard contained in the south central portion of the basin to obtain their drinking
water supply. In 1980, State monitoring studies identified contamination by VOCs,
including TCE and PCE, in large portions of ground water in the Bunker Hill Basin.
Fourteen wells, which supply approximately 25% of the city of San Bernardino's drinking
water supply, also were found to be contaminated above State and Federal levels.
Following regional and State investigations, the State constructed four water treatment
systems to protect the water supply, but after years of testing it became apparent that
(See Attached Page)
17. Document Analysis a. Descriptor*
Record of Decision - Newmark Groundwater Contamination, CA
First Remedial Action
Contaminated Medium: gw
Key Contaminants: VOCs (1,2-DCE, PCE, TCE)
b. Identifiers/Open-ended Term*
c. COSATI Field/Group
ia Availability Statement
19. Security Clan (This Report)
None
20. Security Class (This Page)
None
21. No. of Pages
38
22. Price
(See ANSI-Z39.18)
See Jnafruction* on Revere*
OPTIONAL FORM 272 (4-77)
(Formerly MTIS-35)
Department of Commerce
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EPA/ROD/RO9-93/097
Newmark Groundwater Contamination, CA
First Remedial Action
Abstract (Continued)
the solvents still continued to flow southward, threatening other neighboring communities.
In 1986 and 1989, after several State investigations suggested that the widespread
contamination had resulted from numerous, unidentified sources; several plumes were
identified in the Basin, including an eastern Newmark plume and the western Muscoy plume.
In 1990, aerial photographs taken as part of EPA investigations, along with reports of
witnesses, suggested that the primary source of contamination was the result of
intermittent, improper disposal activities from the 1950s to 1970s at a solvent disposal
pit (cat pit) located at the former site of the San Bernardino airport, near the Newmark
wellfield. However, this could not explain the fact that the solvents also were found in
wells scattered throughout the west side of the Shandin Hills, so EPA and the State now
believe that the contamination is not from a single source. Additionally, at one point,
EPA thought the Newmark and Muscoy plumes were distinct, but additional well drilling in
1992 confirmed that ground water flows from the west to east through a previously
undiscovered channel. Based on this information obtained during the RI, the San
Bernardino plume is no longer suspected to be the source of the contamination, and it is
now believed that the principle contaminant source stems from the northwest side of the
Shandin Hills, and most likely contributes to both plumes. Although the actual
contamination source has not been identified yet, several possible sources in the area
that currently are under investigation include Camp Ono, a former army base; an inactive
county landfill; and an area of industrial development. This ROD addresses an interim
remedy for the area of ground water contamination north and east of the Shandin Hills, as
the Newmark OU. A separate action will address the ground water contamination west of the
Shandin Hills, as the Muscoy OU. The primary contaminants of concern affecting the ground
water are VOCs, including 1,2-DCE, PCE, and TCE.
The selected remedial action for this site includes extracting and treating contaminated
ground water onsite, using either granular activated carbon (GAC) filtration, an
innovative modification of liquid phase GAC, known as advanced oxidation, or air
stripping, with vapor phase GAC to control air emissions, as determined during the RD
stage; piping the treated water to the public water supply system for distribution;
providing for a contingent remedy to recharge the treated water into the aquifer through
reinjection, if the public water supply does not accept all or any of the treated water;
and monitoring ground water. The estimated present worth cost for this remedial action is
$49,900,000, which includes an unspecified O&M cost for 33 years.
PERFORMANCE STANDARDS OR GOALS:
Ground water cleanup goals are based on the more stringent of State standards or SDWA
MCLs, and are expected to be met in the final action for this site.
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NEWMARK OPERABLE UNIT
RECORD OF DECISION
PART I: DECLARATION
PART II: DECISION SUMMARY
PART III: RESPONSIVENESS SUMMARY
NEWMARK GROUNDWATER CONTAMINATION SUPERFUND SITE
SAN BERNARDINO, CALIFORNIA
United States Environmental Protection Agency
Region 9 - San Francisco, California
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NEWMARK Record of Decision ii August 3. 1993
TABLE OP CONTENTS
Page No.
Part I. Declaration 1
Part II. Decision Summary 4
1.0 Site Location and Description 4
2.0 Site History ' 7
3.0 Enforcement Activities 10
4.0 Highlights of Community Participation 10
5.0 Scope and Role of the Operable Unit 12
6.0 Summary of Newmark OU Site
Characteristics 13
7.0 Summary of Site Risks 13
8.0 Description of Alternatives 16
9.0 Summary of Comparative Analysis
of Alternatives 18
10.0 Applicable or Relevant and Appropriate
Requirements 22
11.0 The Selected Remedy 31
12.0 Statutory Determinations 33
13.0 Documentation of Significant Changes "34
Part III. Responsiveness Summary 35
Executive Summary 35
Part I - Responses to Written Comments 37
Part II - Responses to Comments and Questions 45
at Public Meeting Held April 14, 1993
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NEWMARK Record of Decision 1 August 3. 1993
RECORD OF DECISION
NEWMARK OPERABLE UNIT INTERIM REMEDY
PART I. DECLARATION
SITE NAME AND LOCATION
Newmark Groundwater Contamination Superfund Site
Newmark Operable Unit
San Bernardino, California
STATEMENT OF BASIS AND PURPOSE
This decision document presents the selected remedial action
for the Newmark Operable Unit, Newmark Groundwater Contamination
Superfund site, chosen in accordance with CERCLA as amended by SARA
and, to the extent practicable, the National Contingency Plan.
This decision is based on the administrative record for this
operable unit.
In a letter to EPA dated July 29, 1993 the State of California
concurred with the selected remedy for the Newmark OU.
ASSESSMENT OF THE SITE
Actual or threatened releases of hazardous substances from
this site, if not addressed by implementing the response action
selected in this ROD, may present an imminent and substantial
endangerment to public health, welfare or the environment.
DESCRIPTION OF THE REMEDY
EPA has selected an interim.remedy for the Newmark plume of
groundwater contamination in the Newmark Groundwater Contamination
Superfund Site. This portion of the site cleanup is referred to as
the Newmark Operable Unit (OU) . The Newmark OU is an interim
action focusing on contamination in the underground water supply in
the Bunker Hill Basin of San Bernardino, north and east of the
Shandin Hills (Figures 1 and 2). The portion of the groundwater
contamination west of the Shandin Hills, called the Muscoy OU, will
be addressed in a separate action. An OU is a discrete action that
comprises an incremental step toward comprehensively addressing
Superfund site problems. The remedy and all of the alternatives
presented in the feasibility study were developed to meet the
following specific objectives for the Newmark OU:
• To inhibit migration of groundwater contamination into
clean portions of the aquifer;
• To limit 'additional contamination from continuing to flow
into the Newmark OU plume area;
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NEWMARK Record of Decision 2 August 3, 1993
• To begin to remove contaminants from the groundwater
plume for eventual restoration of the aquifer to
beneficial uses (This is a long-term project objective
rather than an immediate objective of the interim
action.)
The remedy involves groundwater extraction (pumping) and
treatment of 8,000 gallons per minute (gpm) in the vicinity of 14th
Street, between Arrowhead and Waterman Avenues, at the leading edge
of the contaminant plume, and an additional 4,000 gpm at the
Newmark wellfield (near 48th Street and Little Mountain Drive)
where the contamination enters the eastern part of the valley (Fig.
2). The exact number, location and other design specifics of new
extraction wells will be determined during the remedial design
phase of the project to inhibit the migration of the contaminant
plume most effectively.
All the extracted contaminated groundwater shall be treated to
remove VOCs by either of two proven treatment technologies:
granular activated carbon (GAG) filtration or air stripping. EPA
determined during the Feasibility Study (March 1993) that these
treatment technologies are equally effective at removing VOCs and
are similar in cost at this OU. Both technologies have been proven
to be reliable in similar applications. It is acceptable to use
one technology for the northern (Newmark wellfield) facility and
the other at the southern treatment facility. As a result of
comments received during the public comment period, EPA may use a
modification of liquid phase GAC (Advanced Oxidation pretreatment)
if this modification proves to be effective and economical during
design phase testing and analysis. The VOC treatment technology
which best meets the objectives of the remedy for the Newmark OU
will be determined during the remedial design phase, when more
detailed information is available to assess effectiveness and cost.
After treatment, the water shall meet drinking water standards
(maximum contaminant levels or MCLs) for VOCs. If air stripping
treatment is selected, air emissions shall be treated using the
best available control technology (e.g., vapor phase GAC) to ensure
that all air emissions meet applicable or relevant and appropriate
requirements.
The treated water will be piped to the public water supply
system for distribution. Groundwater monitoring wells will be
installed and sampled regularly to help evaluate the effectiveness
of the remedy.
If the public water supply system does not accept any or all
of the treated water (possibly due to water supply needs), any
remaining portion of water will be recharged into the aquifer via
reinjection wells near the edge of the plume. The number, location
and design of the reinjection wells will be determined during the
remedial design phase to best meet the objectives of the remedy and
meet applicable or relevant and appropriate requirements.
The total duration of the Newmark OU interim remedy will be 33
years, with the first three years for design and construction. EPA
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NEWMARK Record of Decision 3 August 3. 1993
will review this action every five years throughout this interim
remedy period and again at the conclusion of this period.
The remedial action for the Newmark OU represents a discrete
element in the overall long-term remediation of groundwater at the
Newmark Groundwater Contamination Superfund Site. The objectives
of this interim action (i.e. inhibiting migration of groundwater
contamination to clean portions of. the aquifer, controlling
additional contamination from entering this portion of the aquifer,
and beginning to remove contaminant mass from the aquifer in the
Newmark Plume) would not be inconsistent with nor preclude
implementation of any final, overall remedial action or actions
selected by EPA in the future for the Newmark Groundwater
Contamination Superfund Project.
EPA is the lead agency for this project and the Department of
Toxic Substances Control of the State of California Environmental
Protection Agency is the support agency.
DECLARATION
This interim action is protective of human health and the
environment, complies with Federal and State applicable or relevant
and appropriate requirements directly associated with this action
and is cost effective. This action utilizes permanent solutions
and alternative treatment (or resource recovery) technologies to
the maximum extent practicable, given the limited scope of the
action. Because this action does not constitute the final remedy
for the site, the statutory preference for remedies that employ
treatment that reduces toxicity, mobility, or volume as a principal
element will be addressed at the time of the final response action.
Subsequent actions are planned to fully address the principal
threats at these sites.
Because this remedy will result in hazardous substances
remaining on-site above health-based levels, EPA shall conduct a
review, pursuant to CERCLA Section 121; 42 U.S.C. Section 9621, at
least once every five years after commencement of remedial action
to ensure that the remedy continues to provide adequate protection
of human health., and the environment.
John C.'Wise / Date
Acting Regional Administrator
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NEWMARK Record of Decision 4 August 3. 1993
PART II- DECISION SUMMARY
This Decision Summary provides an overview of the Nevmark ou
interim remedy, including a description of the nature and extent of
contamination *:o be addressed, and the remedial alternatives, the
comparative analysis of the remedial alternatives, a description of
the selected remedy and the rationale for remedy selection.
1.Q SITE LOCATION AND DESCRIPTION
The Newmark OU is located within the Bunker Hill Basin (also
known as the Upper Santa Ana River Basin) in San Bernardino,
California. The following sections present a basin description,
regulatory history, and a summary of the Remedial Investigation and
Feasibility Study (RI/FS) activities within the Newmark Superfund
Site.
l.l Description of the Bunker Hill Basin
The Newmark Groundwater Contamination affects a large portion
of a 110 square mile aquifer in the San Bernardino Valley of
southern California. (Figure 1). The aquifer, known as the Bunker
Hill Basin, is bounded by the San Bernardino and San Gabriel
Mountains to the north, the Crafton Hills and badlands on the
southeast, and by a hydrogeologic barrier formed by the San Jacinto
fault along the southwest. (Figure 2) Water flowing from all parts
of the aquifer join in a confined 'artesian zone' before leaving
the basin where the Santa Ana River crosses the San Jacinto
faultline.
Coarse erosional material (alluvial and river channel
deposits) have accumulated in the this area of the basin to depths
of 400 to over 1900 feet, atop older formations that act as
barriers to further vertical movement. A fold in one of these
impermeable bottom formations forms the Shandin Hills (formerly
called Bunker Hill in reference to military emplacements from the
WWII era), which force groundwater flowing from the north and west
to flow aroundl either side rather than directly south toward the
Santa Ana River.
Most of the western portion of the basin is an unconfined
aquifer, with no substantial barriers to infiltration from the
surface. In the lowest area of the basin (the south-central
portion around the Santa Ana River), several extensive clay layers
have 'formed an aquitard, overlying and capping the water-bearing
sand and gravel aquifers. This confined portion of the aquifer
produces tremendous supplies of water for nearby communities.
The aquifer receives rainfall and natural runoff from the
surrounding mountains, collected floodwaters from rivers, creeks
and washes, and water imported from outside the region that is
spread over percolation basins. According to the San Bernardino
Municipal Water District, the Bunker Hill Basin is capable of
storing approximately 5 million acre-feet (1.6 trillion gallons)
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EXPLANATION
UNCONSOUDATED DEPOSTTS
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IXRECTXINOF GROUNDWATII
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FIGURE 2 • Altitude ol potenHometrtc surface and direction of ground-water movement, summer 1986.
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NEWMARK Record cf Decision 7 August 3, 1993
and producing 250,000 acre-feet (81 billion gallons) each year.
Nearly a half-million residents of San Bernardino, Riverside and
surrounding communities rely on this portion of the aquifer for at
least part of their water supply.
The Newmark OU lies almost entirely within the city of San
Bernardino. Residential and commercial use predominates throughout
the OU, although some industrial development has been identified.
Very little of the area remains undeveloped.
1.2 Description and Background of the Newmark OU .
The solvents (tetrachloroethene, PCE, and trichloroethene,
TCE) spreading from the Newmark Superfund site threaten
approximately one-half of the Bunker Hill Basin.
The EPA placed the Newroark site on the National Priorities
List (NPL) in March, 1989. At that time,. EPA believed the eastern
(Newmark) plume of contamination to be completely separate from the
western (Muscoy) groundwater contamination. Results of earlier
investigations identified a possible contaminant source (a disposal
pit for waste liquids at a former airport) near the Newmark
wellfield.
The EPA Remedial Investigation (RI) began in late 1990. In
1992 eight sets of monitoring wells were drilled and sampled in the
Newmark OU, and nearby city and state wells were also sampled by
EPA. PCE and TCE were the most prevalent contaminants in all the
contaminated wells. Other VOCs have also been detected in trace
quantities. Results from the RI showed that the originally
suspected source of the Newmark plume was not currently a source of
contamination. Additional well drilling in the summer of 1992
traced groundwater contamination through a previously undiscovered
underground channel flowing from the western (Muscoy) side of the
valley. The Newmark site was officially expanded in September,
1992 to include the Muscoy plume. EPA began additional RI studies
for the Muscoy plume and finished a feasibility study (FS) for the
Newmark OU which evaluated a range of cleanup alternatives for
addressing the.five mile long contaminated groundwater plume. The
RI/FS report for the Newmark OU was finalized in March, 1993.
2.0 SITE HISTORY
In 1980, the California Department of Health Services (DHS)
initiated a monitoring program in San Bernardino to test for the
presence of industrial chemicals in the water from public supply
wells. The results of initial tests and of subsequent testing
revealed the presence of PCE and TCE contamination in large
portions of the groundwater of the Bunker Hill Basin.
Fourteen wells operated by the city of San Bernardino Water
Department in the North San Bernardino / Muscoy area were found to
contain concentrations of PCE and TCE above the state and federal
MCLs of 5 parts per billion (ppb) for both TCE and PCE. The
solvents were found in wells scattered around the north, east and
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NEWMARK Record of Decision 8 August 3, 1993
west sides of the Shandin Hills. (Figure 3) The affected wells had
supplied nearly 25 percent of the water for the city of San
Bernardino. As of 1993, a total of thirteen public water supply
wells have been contaminated by the solvents apparently spreading
from the Newmark plume, and seven water supply wells have been
affected in the area of the Muscoy plume.
Following investigations by the Santa Ana Regional Water
Quality Control Board and California Department of Health Services
(now the California EPA Department of Toxic Substances Control),
the state provided over $6 million to construct three water
treatment systems, with a fourth under construction, to protect the
public water supply. After years of testing it became apparent
that the solvents in the groundwater were continuing to flow south,
threatening many more wells operated by San Bernardino, Riverside
and other communities. The state reguested federal involvement to
address this regional problem.
It should be noted that the cities of San Bernardino,
Riverside and other water agencies in the area closely monitor the
quality of drinking water delivered to residents. The water served
to residents meets all Federal and state drinking water
requirements.
The state investigations published in 1986 and 1989 both
suggested that the widespread contamination in northern San
Bernardino probably resulted from numerous small, unidentified
sources. The Shandin Hills and nearby hill formations were assumed
to separate the eastern (Newmark area) aquifer from the western
(Muscoy area) aquifer, making it unlikely that all 14 wells could
have been contaminated from a single source.
Continued monitoring of existing water supply wells and
monitoring wells constructed by the state established a record of
contamination relatively uniform in composition and concentration
throughout the area north and east of the Shandin Hills. This
pattern strongly suggested a single plume in this area.
Aerial photographic analysis was completed . by EPA's
Environmental "Monitoring Systems Laboratory in September, 1990.
This analysis, along with interviews of witnesses, suggested that
the primary source of contamination was a suspected solvent
disposal pit ('cat pit') on the former site of the private San
Bernardino Airport. This activity occurred from the late 1950's
intermittently through the early 1970's. Several minor activities
in different parts of the airport site were also identified as
potential waste releases. No other sources could be identified
between the disposal site and the closest uncontaminated wells
upgradient. The plume from this single source would extend over
four miles. The waste disposal pit was also within several hundred
feet of the Newmark wellfield (four City of San Bernardino Water
Department wells) . These wells exhibited the highest concentration
of contaminants measured in any wells in the area, nearly 200 fJ.g/1.
(parts per billion) of PCE.
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FIGURE 3: LOCATION OF PUBLIC WATER SUPPLY WELLS AND IDENTIFIED CONTAMINANT PLUMES
IN THE BUNKER HILL GROUNDWATER BASIN
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NEWMARK Record of Decision 10 August 3, 1993
In 1984-85, the area near the "cat pit", which was later
identified as the probable contaminant source, was developed into
a residential community.
Based on information obtained during the Remedial
Investigation, the San Bernardino Airport site is no longer
suspected to be the source of the Newmark Plume. It is now
believed that the principle source (or sources) lies on the west
side of the Shandin Hills and likely contributes to both the
Newmark and Muscoy Plumes.
While ongoing investigations attempt to identify the source,
EPA determined that the Newmark plume could be addressed as an
interim action (the Newmark OU).
3.0 ENFORCEMENT ACTIVITIES
The results of the Remedial Investigation and other
investigations undertaken by EPA and state agencies indicate that
the project lead for the Newmark OU will remain with EPA until a
probable source is located.
Considerable effort was expended on a PRP search while the San
Bernardino Airport site was suspected to be the source of the
contamination. Results of the Remedial Investigation traced the
source more than one mile upgradient of the suspected source. No
residual contamination was found in the unsaturated zone or the
upper portion of the aquifer immediately beneath former disposal
pits. The airport site is no longer considered a likely source of
the contamination.
The focus of the ongoing PRP search will be potential sources
located to the northwest of the Shandin Hills. These potential
sources include Camp Ono (a WWII-era army base decommissioned in
1947 and subsequently developed for residential and
commercial/industrial use), a closed county landfill, and an area
of industrial,development. The Department of Defense was sent a
copy of the Newmark Proposed Plan at the start of the public
comment period, along with an information request letter concerning
the operations at the former Camp Ono.
4.0 HIGHLIGHTS OF COMMUNITY PARTICIPATION
EPA's preferred alternative, as well as four other
alternatives were described in EPA's Proposed Plan for the Newmark
OU (March 1993) . The Proposed Plan was in the form of a fact sheet
and was distributed to all parties on EPA's mailing list for the
Newmark project. The original 30 day public comment period was
extended to 6 weeks (45 days) after EPA received requests for
extensions from members of the public. The public comment period
closed on May 5, 1993. EPA received approximately 50 comments.
These comments and EPA's responses to these comments are summarized
in Part III (the Responsiveness Summary) of this ROD.
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NEWMARK Record of Decision 11 August 3, 1993
A press release to announce the release of the Proposed Plan
was issued March 17, 1993. Notice of the public meeting as well as
the availability of the Proposed Plan was published in the Inland
Empire Sun on March 18, 1993. In addition, several newspaper
articles were written about the remedial investigation, the
feasibility study and the Proposed Plan for the Newmark OU
including: Inland Empire Sun - March 18, 1993; Riverside Press-
Enterprise - March 18, 1993. A map of the Newmark OU was provided
in the Proposed Plan and the various newspaper articles published
maps and described the area that would be impacted by the Newmark
OU. " . . .
A public meeting was held in the City of San Bernardino
Council Chambers on April 14, 1993, to discuss EPA's preferred
alternative and the other alternatives. At this meeting EPA gave
a brief presentation regarding the Proposed Plan, answered
questions, and accepted comments from members of the public. This
meeting was broadcast live on the local cable channel.
EPA expended considerable effort developing strong community
relations. A Technical Advisory Committee has been successful in
maintaining close communication with local and state agencies. For
communication with the local community, three principle mechanisms
have been employed: formal presentations (open houses, meetings
with organizations and fact sheet distribution), contact with the
print and electronic media and informal discussions with home-
owners ' associations and individuals.
The San Bernardino and Riverside papers have published a
number of positive and well-researched articles about the project.
Major television networks broadcast reports of the drilling
operation in February, 1992. The Project Manager participated in
a 90 minute call-in talk show on the public television station in
August, 1992.
Invitations were accepted to speak at a city-wide Neighborhood
Watch meeting and at a San Bernardino "town-hall" meeting sponsored
by the California Water Education Foundation. Two open house
meetings were held to introduce the field work in February, 1992,
and another open house was held on-site for the community and press
shortly after drilling began. Three fact sheets in addition to the
Proposed Plan have been distributed.
Three different home-owners' associations accepted EPA's offer
for informal discussions of the project. Drilling around these
communities was greatly facilitated by open communication.
Presentations were made to the staff and teachers at a local
school, and the Project Manager taught the 5th grade class about
groundwater and chemical pollution as it relates to the Newmark
site.
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NEWMARK Record of Decision 12 August 3, 1993
5.0 SCOPE AND ROLE OF THE OPERABLE UNIT
The interim remedial action for the Newmark OU represents a
discrete element in the overall long-term remediation of
groundwater in the San Bernardino area. Since the source has not
been identified, the final overall plan for the remediation of the
entire Newmark Groundwater Contamination Site has not yet been
determined. The Newmark plume constitutes a major portion of the
contaminated aquifer and this remedy will be a significant step
toward eventual remediation. EPA does not.expect these objectives
to be inconsistent with, nor preclude, any final action for the
entire site.
The objectives of the Newmark OU are:
• To inhibit migration of groundwater contamination into
clean portions of the aquifer;
• To limit additional contamination from continuing to flow
into the Newmark OU plume area;
• To begin to remove contaminants from the groundwater
plume for eventual restoration of the aquifer to
beneficial uses (This is a long-term project objective
rather than an immediate objective of the interim
action.)
The analysis of the no-action option indicates that unless
this action is implemented, the contamination will continue to
spread to clean areas of the aquifer which are currently used as
important sources of drinking water.
EPA is currently using the results of the Newmark OU remedial
investigation in basinwide feasibility studies to address VOC
contamination in the Muscoy. OU and to investigate potential
sources. As part of the Muscoy OU FS, EPA is revising and
recalibrating .the groundwater flow model for the entire site to
incorporate the most recent data. When sufficient information is
available on the contaminant source and transport from the source,
EPA will review and evaluate various groundwater remediation
options for the complete site. It is expected that the Newmark OU
remedy will constitute an integral part of the complete remedy.
EPA will continue to monitor aquifer behavior and contaminant
transport as part of this interim action. The information gathered
will be important in the analysis of a remedy for the entire
Newmark site.
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NEWMARK Record of Decision 13 August 3, 1993
6.0 SUMMARY OF NEWMARK OU SITE CHARACTERISTICS
Results of EPA's Remedial Investigation provided critical
understanding in three general areas: groundwater flow
characteristics, contaminant identification and concentration, and
potential for exposure through the unsaturated zone.
The result that was least expected was that a significant flow
of contaminated groundwater was entering the eastern (Newmark OU)
side of the basin from the western portion (Muscoy OU) . Most
recharge to the Newmark OU part, of the Bunker Hill. Basin does
originate along the San Bernardino Mountains to the north, and this
source is not contaminated. Another important observation was that
clay or silt layers that would inhibit vertical contaminant
migration were not present in the monitoring well drilled near the
leading edge of the plume. The contaminants cannot be expected to
remain in an isolated vertical layer. A groundwater flow model was
successfully developed to describe the aquifer behavior.
The contaminants identified were predominantly chlorinated
solvents. Tetrachloroethene (PCE) was found in all contaminated
wells at concentrations less than 40 parts per billion (ppb) .
Trichloroethene (TCE) was the next most common contaminant, and
never exceeded 10 ppb. Other related solvents were identified at
concentrations below drinking water standards. Chlorof luorocarbons
(freons) were also observed. Monitoring wells were constructed to
collect samples at two or more depths at each well location.
Generally, the highest concentrations of contaminants were found in
the deeper wells. Typically, a well near bedrock (about 500 feet
deep) would have PCE levels of 10 to 20 ppb while the well in the
upper part of the aquifer would have PCE less than 2 ppb.
Monitoring well data compared quite closely with data from nearby
water production wells.
Subsurface soil samples at the originally suspected source had
no detectable levels of contaminants. Air samples from homes.
directly above the contaminant plume had no more volatile chemicals
than samples from homes outside the plume area. Levels were not
different from, values observed in homes throughout the Los Angeles
metropolitan area. These results confirmed that volatilization
from the subsurface does not provide a measurable exposure pathway.
7.0 SUMMARY OF SITE RISKS
Baseline risk assessments are conducted at Superfund sites to
fulfill one of the requirements of the National Oil and Hazardous
Substances Pollution Contingency Plan (NCP). The NCP (40 CFR Part
300) requires development of a baseline risk assessment at sites
listed on the National Priorities List (NPL) under CERCLA. The
CERCLA process for baseline risk assessments is intended to address
both human health and the environment. However, due to the nature
of the contamination at the site and the highly urbanized setting
of the Newmark OU, the focus of the baseline risk assessment was on
human health issues, rather than environmental issues.
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NEWMARK Record of Decision 14 August 3, 1993
The objective of the baseline risk assessment for the Newmark
OU was to evaluate the human health and environmental risks posed
by the contaminated groundwater if it were to be used as a source
of drinking water without treatment. The baseline risk assessment
incorporated the water quality information generated during the RI
field investigation and sampling program to estimate current and
future human health and environmental risks.
The risk assessment was conducted in accordance with EPA
guidance including: Guidance for Conducting Remedial Investigation
and Feasibility Studies under CERCLA (USEPA, 1988), Risk Assessment
Guidance for Superfund. Vol. I Health Evaluation Manual (Part AV
and Vol. 2 Ecological Assessment (USEPA, 1989), The Exposure
Factors Handbook (USEPA, 1989), and Risk Assessment Guidance for
Superfund Human Health Risk Assessment. USEPA Region IX
Recommendations (USEPA, 1989).
A risk assessment involves the qualitative and quantitative
characterization of potential health effects of specific chemicals
on individuals or populations. The risk assessment process
comprises four basic steps: 1) hazard identification, 2) dose-
response assessment, 3) exposure assessment, and 4) risk
characterization. The purpose of each element is as follows:
• Hazard identification characterizes the potential threat
to human health and the environment posed by the detected
constituents.
• Dose response assessment critically examines the
toxicological data used to determine the relationship
between the experimentally administered animal dose and
the predicted response (e.g., cancer incidence) in a
receptor.
• Exposure assessment estimates the magnitude, frequency,
and duration of human exposures to chemicals..
Risk characterization estimates the incidence. of or
potential for an adverse health or environmental effect
under the conditions of exposure defined in the exposure
assessment.
Human Health Risk Assessment
Risk assessments estimate the possibility that additional
occurrences of cancer will result from exposure to contamination.
The background probability of developing cancer from all causes in
California is approximately one in four (or 250,000 in a million).
An excess cancer risk of 1 in a million means that a person exposed
to a certain level of contamination would increase the risk of
developing cancer from 250,000 in a million to 250,001 in a million
as a result of the exposure. EPA considers excess cancer risks
greater than 100 in a million to be unacceptable.
In preparing risk assessments, EPA uses very conservative
assumptions that weigh in favor of protecting public health. For
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NEWMARK Record of Decision 15 August 3. 1993
example, EPA may assume that individuals consume two liters of
drinking water from wells situated within a contaminant plume every
day for a 30-year period, even though typical exposure to the
chemical would be far less.
EPA included two potential exposure routes (ways the
contamination gets into the body) in the risk assessment:
• drinking the groundwater during residential use; and
• inhaling the chemicals in groundwater as vapors .during
showering.
Skin contact with contaminated water was also considered but
EPA found that it didn't pose a significant risk. Results of the
RI indicated that direct exposure to volatile organic compounds
(VOCs) from the soil or water 100 feet below ground was
insignificant at this site.
Chemicals of potential concern in the Newmark OU used in the
risk assessment calculations included: PCE, TCE, cis 1,2-
dichloroethene (DCE), and six other VOCs detected in at least one
well. EPA will continue to monitor the groundwater in the Newmark
OU for any changes that would affect the risk analysis.
The results of the risk assessment indicated that the current
contaminant levels in the aquifer of the Newmark OU would not meet
state or Federal drinking water standards if this water were to be
delivered directly to local residents, without being treated.
However, the levels are currently below the concentrations that
would pose an unacceptable risk to human health, as defined by
CERCLA. If the groundwater were used as a drinking water source
without treatment, the chance of developing cancer during a
lifetime would increase by as much as 20 in a million. EPA is
taking an action at the Newmark OU in order to meet the drinking
water standards (MCLs) even though the .risk levels do not exceed
100 in a million. . " .
The baseline risk assessment for the Newmark OU is presented
in the Remedial Investigation and Feasibility Study Report for the
Newmark.OU (March 1993).
Environmental Risk Assessment
Given the present developed condition of the site and the
major' exposure pathway consideration of contaminated groundwater,
there was no expectation for significant impact to potential
environmental receptors. Urbanization has already replaced habitat
potential; therefore, no significant number of receptors appeared
to be present. There appeared to be no apparent mechanism for
exposure to environmental receptors from contaminated groundwater.
Also, there was no indication that future site plans would
reinstate habitat and thereby recreate a potential for
environmental receptors in the future.
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NEWMARK Record of Decision 16 August 3, 1993
8.0 DESCRIPTION OF ALTERNATIVES
Development of Alternatives to Meet Project Objectives
Before developing a range of cleanup alternatives for
evaluation, EPA identified the objectives of the interim cleanup
for the Newmark OU. All of the alternatives were screened for: 1)
effectiveness at protecting public health and the environment, 2)
technical feasibility (implementability), and 3) cost. In
addition, the alternatives were developed to meet the specific
cleanup objectives for the Newmark OU described previously.
IUP Alternatives
Based on the results of the RI, EPA identified five cleanup
alternatives for addressing groundwater contamination of the
Newmark OU. Detailed descriptions of these alternatives are
provided in the Newmark OU RI/FS Report (March 1993) . Rather than
including all potential combinations of extraction locations and
amounts, the initial screening process identified the most
efficient extraction scenario that would meet the stated
objectives. The five alternatives were evaluated based on nine
specific criteria: 1) Overall Protection of Human Health and the
Environment, 2) Compliance with Applicable or Relevant and
Appropriate Requirements (ARARs), 3) Long-term Effectiveness and
Permanence, 4) Reduction of Toxicity, Mobility or Volume through
Treatment, 5) Short-term Effectiveness, 6) Implementability, 7)
Cost, 8) State Acceptance, and 9) Community Acceptance.
With the exception of the Alternative 1 - No Action, all of
the alternatives involve the extraction of 4,000 gallons per minute
(gpm) of groundwater near the Newmark wellfield and 8,000 gpm of
groundwater near the leading edge of the plume (approximately at
14th Street between Arrowhead and Waterman Avenues) for a period of
30 years. Individual wells would pump from 800 to 2,000 gpm, the
range for a typical city drinking water well..
A computer model was used to determine that these extraction
rates would result in effective inhibition of plume migration and
optimal contamination removal for this interim action. With the
exception of Alternative 1 - No Action, all of the alternatives
would involve the construction and operation of a VOC treatment
system, construction and sampling of additional monitoring wells,
and analysis of any changes in the current operations of nearby
public water supply wells.
During the first three years after the ROD is signed, the
remedy would go through the remedial design and initial
implementation stages. EPA must plan, build the equipment and test
it to make sure it functions properly.
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NEWMARK Record of Decision 17 August 3. 1993
ALTERNATIVE 1: No Action
This alternative serves as a baseline to compare other
alternatives. This alternative is evaluated to determine the risks
that would be posed to public health and the environment if no
action were taken to treat or contain the contamination. The No
Action Alternative would involve only groundwater monitoring; no
additional cleanup activities would be conducted. The cost of
constructing the necessary monitoring wells and sampling them over
30 years would be approximately $3.5 million (present net worth).
ALTERNATIVE 2: Extract/Treat(Granular Activated Carbon)/Public
Water System
Extraction
Alternative 2 involves the extraction of 8,000 gpm of
contaminated groundwater placed at the leading edge of the Newmark
plume and extraction of 4,000 gpm within the plume near the Newmark
wellfield. The extraction wells would be located to inhibit most
effectively the migration of the contaminant plume.
Treatment
The extracted groundwater would be transmitted via underground
piping to Granular Activated Carbon (GAC) treatment plants (two
separate treatment plants, one for each set of extraction wells).
(Note that Alternative 3, involving treatment by air stripping, is
considered by EPA to be equivalent to Alternative 2, and may be
substituted for all or part of Alternative 2 during the design
phase of the project.)
Final Use of Treated Water
The treated water would meet all legal requirements for
drinking water and would be piped to the public supply system for
distribution. Groundwater monitoring wells would be installed to
evaluate the effectiveness of the remedial action. Following.
approximately 2 to 3 years for design and construction,' this system
would operate for 30 years. Operation of nearby public water
supply wells is not expected to interfere with this remedy,
although any significant changes in operations would be analyzed to
determine the effect on this cleanup action. EPA will conduct a
review of the project effectiveness every five years.
ALTERNATIVE 3: Extract/Treat(Air Stripping with Emission
Control)/Public Water System
Alternative 3 involves the same extraction system, final
distribution and monitoring design as Alternative 2. Alternative
3 differs from Alternative 2 in the treatment of the extracted
groundwater to remove VOCs to meet drinking water standards. In
Alternative 3, the extracted contaminated water would be treated by
air stripping with emission control to meet the South Coast Air
Quality Management District's requirement for best available
control technology. Currently, vapor-phase granular activated
carbon meets this requirement, and EPA used this technology for
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NEWMARK Record of Decision 18 August 3, 1993
cost and .effectiveness analysis. New emissions control
technologies developed prior to the final design could be
considered if they meet the air quality requirement. Air stripping
is essentially equal to GAC (Alternative 2) in effectiveness,
technical feasibility and the remaining criteria.
Alternative 4: Extract/Treat (Advanced Oxidation - Peroxide/Ozone)/
Public Water System
Alternative 4 involves the same extraction, end use and
monitoring design as Alternative 2. The extracted water would be
treated for VOCs using an advanced oxidation process that uses
peroxide and ozone to destroy (oxidize) the contaminants (rather
than transferring the contaminants to a carbon filter). The
advanced oxidation process was the primary treatment method for
this alternative. The treated water would meet all legal
requirements for a drinking water supply and would be piped to a
public distribution system. Groundwater monitoring wells would be
installed to evaluate the effectiveness of the action.
ALTERNATIVE 5: Extract/Treat (GAC or Air Stripping)/Return to the
Aquifer via Reinjection).
Alternative 5 involves the same extraction, treatment and
monitoring designs as Alternative 2 (including the option to use
either GAC or air stripping to treat the extracted water for VOCs).
The water would be returned to the aquifer in reinjection wells
downgradient from the extraction wells. The treated water would
meet drinking water standards before being returned to the aquifer.
9.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES
A comparative analysis of the alternatives against the nine
evaluation criteria is presented in this, section.
No Action versus the Nine Criteria, clearly, Alternative 1 would
not be effective in the short- and long-term in protecting human
health and the environment as it does not provide for removing any
contaminants from the aquifer, for inhibiting further downgradient
contaminant plume migration, or for reducing the toxicity, mobility
and volume of contaminants through treatment. Implementing the
no-action alternative would be simple and inexpensive since it
involves only groundwater monitoring. As indicated by the baseline
risk assessment presented in the RI Report, Alternative 1 could
pose both carcinogenic and non-carcinogenic risk if a person were
exposed to the groundwater from the upper zone of the aquifer,
although these risks are below the 100 in a million excess risk
level (10~4) which EPA considers generally unacceptable. The
current contaminant level would not meet state or federal drinking
water standards if this water were to be delivered directly to
local residents without treatment. Loss of a valuable water
resource from continued degradation of the aquifer is a major
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NEWMARK Record of Decision 19 August 3. 1993
concern for the State and the public.
Overall Protection of Human Health and the Environment, Short Term
Effectiveness and Long Term Effectiveness.
Alternatives 2, 3,4 and 5 have the same effectiveness in the short
and long term in reducing the risk to human health and the
environment by removing contaminants from the aquifer; by
inhibiting further downgradient contaminant migration; and by
reducing the toxicity, mobility and volume of contaminants in the
aquifer. .
Reduction of Toxicity, Mobility and Volume through Treatment. The
VOC treatment technologies used in Alternatives 2, 3 and 5 (either
air stripping with emission control (e.g., vapor-phase GAC
adsorption) or liquid phase GAC adsorption) are technically
feasible and effective in meeting ARARs for VOCs in the extracted
and treated groundwater. Treatment of the extracted contaminated
groundwater via air stripping with vapor-phase GAC adsorption or
liquid phase GAC adsorption would reduce substantially the toxicity
and mobility of contaminants in the aqueous phase. The adsorption
of contaminants onto the GAC would reduce the volume of
contaminated media. However, a substantially larger quantity of
contaminated GAC media would be generated with either air stripping
with vapor-phase GAC or liquid-phase GAC systems compared to
perozone oxidation (which is a destructive technology) followed by
either air stripping with vapor-phase GAC adsorption or liquid-
phase GAC. This contaminated GAC would require disposal or
regeneration. During the design phase, an alternative emission
control technology will be tested to eliminate the need for vapor-
phase GAC while meeting the Best Available Control Technology
requirement.
Treatment of the extracted contaminated groundwater via
perozone oxidation in Alternative 4 would destroy greater than 90
percent of the VOCs, and generate a. smaller, quantity of
contaminated GAC media compared .to the. conventional technologies
alone. VOC treatment using perozone oxidation has only been tested
and applied in pilot-scale/limited applications, and limited O&M
data are available. Concern has been expressed over the
reliability of this innovative technology at large-scale
application for drinking water supply treatment. Incomplete
oxidation can lead to the formation of by-products such as
formaldehyde which would also need to addressed. Coupled with the
uncertainties associated with design, capital and operational costs
and d-ay-to-day reliability at a large scale, and finally the fact
that a municipality will be receiving this water, all combine to
make Alternative 4 less preferable than Alternatives 2, 3 and 5
which propose using liquid phase GAC or air stripping for VOC
treatment.
As a result of comments received during the public comment
period, EPA further evaluated the use of an advanced oxidation
system as pretreatment for liquid-phase GAC. Additional research
on perozone use and revised cost estimates based on a bench scale
treatability study can be found in the following technical
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NEWMARK Record of Decision 20 . August 3, 1993
memorandum: Analysis of "Hybrid" Advanced Oxidation Pretreatment/
Activated Carbon Alternative for the Newmark Operable Unit (June
25, 1993) included in the Administrative Record for the Newmark OU.
Pretreatment with a destructive technology has the theoretical
advantage of reducing contaminant mass while enhancing the
operation of a reliable conventional technology. EPA may use this
modification of liquid phase GAC if this modification proves to be
effective and economical during design phase testing and analysis.
Compliance with ARARs. As discussed in the ARARs section (Section
10) of this ROD, since this remedial action is an interim action,
there are no chemical-specific ARARs for aquifer cleanup for any of
the alternatives. For Alternatives 2 through 5, the chemical-
specific ARARs for the treated water from the VOC treatment plant
at this site are Federal MCLs and more stringent State MCLs for
VOCs. Alternatives 2, 3, and 5 are expected to meet these ARARs
for the treated water. There is some uncertainty regarding the
ability of Alternative 4 to meet these ARARs because perozone has
not been used to treat such high concentrations of VOCs at such
high flow rates. Therefore, there is the potential for not meeting
MCLs unless the air stripping or liquid-phase GAC unit following
the perozone system is a redundant treatment system (which would
add substantially to the cost).
For the Alternatives that involve distribution of the treated
water to a public water supply system (Alternatives 2, 3 and 4),
secondary drinking water standards are ARARs. For water that will
be served at the tap, all legal requirements will have to be met.
In Alternative 5, the treated water will meet MCLs for VOCs prior
to return to the aquifer at an on-site location.
Implementability. Technically and administratively, Alternatives
2, 3, and 5 could be implemented. The technologies considered for
groundwater monitoring, extraction, and conveyance are proven and
have been applied extensively. For Alternative 5, the availability
of an appropriate on-site location for reinjection of extracted and
treated groundwater would need to bie addressed.
State and Public Acceptance. Based on comments received during the
public comment period, the public generally expressed support for
Alternatives 2 through 5, although strong reservations were
expressed about alternative 4. EPA received comments from the
City of San Bernardino Water Department, two other water agencies
in the area, and members of the San Bernardino community
specifically in support of Alternatives 2 and 3. Comments received
during the public comment period along with EPA responses are
presented in Part III of this ROD, the Responsiveness Summary. In
a letter dated July 29, 1993, the State (Cal-EPA) concurred with
EPA's selected remedy for the Newmark OU.
Cost. The estimated total present worth of Alternatives 2, 3 and
5 ranges from $47,900,000 to $49,900,000. The total present worth
cost for Alternative 4 is $61,000,000. For alternatives 2, 3 and
4, some of these costs are expected to be offset by the water
supply agencies which accept the treated water. These overall
project costs do not take into account the value of utilizing the
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NEWMARK Record of Decision 21 August 3. 1993
groundwater resource directly as opposed to recharging the water to
the aquifer to be eventually pumped to the surface again prior to
use (Alternative 5).
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NEWMARK Record of Decision 22 August 3. 1993
10.0 APPLICABLE OR RELEVANT AND APPROPRIATE REQUIREMENTS
This section discusses Applicable or Relevant and Appropriate
requirements, (ARARs) for the Newmark OU. Under Section 121(d)(1)
of the Comprehensive Environmental Response, Compensation and
Liability Act of 1980 as amended by the Superfund Amendments and
Reauthorization Act of 1986 (collectively, CERCLA), 42 U.S.C. §
9621(d) remedial actions must attain a level or standard of control
of hazardous substances which complies with ARARs of Federal
environmental laws and more stringent state environmental and
facility siting laws. Only state requirements that are more
stringent than Federal ARARs, and are legally enforceable and
consistently enforced may be ARARs.
Pursuant to Section 121(d) of CERCLA, the on-site portion of
a remedial action selected for a Superfund site must comply with
all ARARs. Any portion of a remedial action which takes place off-
site must comply with all laws legally applicable at the time of
the off-site activity occurs, both administrative and substantive.
An ARAR may be either "applicable", or "relevant and
appropriate", but not both. According to the National Oil and
Hazardous Substances Pollution Contingency Plan (NCP) (40 CFR Part
300) , "applicable" and "relevant and appropriate" are defined as
follows:
• Applicable requirements are those cleanup standards,
standards of control, or other substantive environmental
protection requirements, criteria, or limitations
promulgated under Federal or state environmental or
facility siting laws that specifically address a
hazardous substance, pollutant, contaminant, remedial
action, location, or other circumstance found at a CERCLA
site. Only those state standards that are identified by
a state in a timely manner and that are more stringent
than Federal requirements may be applicable.
"Applicability" implies that.the remedial .action or the
circumstances at the site satisfy all of the
jurisdictional prerequisites of a requirement.
. Relevant and appropriate requirements are those cleanup
standards, standard of control, and other substantive
environmental protection requirements, criteria, or
limitations promulgated under Federal environmental or
State environmental or facility siting laws that, while
not "applicable" to a hazardous substance, pollutant,
contaminant, remedial action, location, or other
circumstance at a CERCLA site, address problems or
situations sufficiently similar to those encountered at
the CERCLA site that their use is well suited to the
particular site. Only those state standards that are
identified in a timely manner and that are more stringent
than Federal requirements may be relevant and
appropriate.
Chemical-Specific ARARs. Chemical-specific ARARs are health- or
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Record of Decision 23 August 3, 1993
risk-based concentration limits, numerical values, or methodologies
for various environmental media (i.e., groundwater, surface water,
air, and soil) that are established for a specific chemical that
may be present in a specific media at the site, or that may be
discharged to the site during remedial activities. These ARARs set
limits on concentrations of specific hazardous substances,
pollutants, and contaminants in the environment. Examples of this
type of ARAR are ambient water quality criteria and drinking water
standards.
Location-Specific ARARs. Location-specific requirements set
restrictions on certain types of activities based on site
characteristics. Federal and state location-specific ARARs are
restrictions placed on the concentration of a contaminant or the
activities to be conducted because they are in a specific location.
Examples of special locations possibly requiring ARARs may include
flood plains, wetlands, historic places, and sensitive ecosystems
or habitats.
Action-Specific ARARs. Action-specific requirements are
technology- or activity-based requirements which are triggered by
the type of remedial activities under consideration. Examples are
Resource, Conservation and Recovery Act (RCRA) regulations for
waste treatment, storage or disposal.
Neither CERCLA nor the National Oil and Hazardous Substances
Pollution Contingency Plan (NCP) (400 C.F.R. Part 300) provides
across-the-board standards for determining whether a particular
remedy will result in an adequate cleanup at a particular site.
Rather, the process recognizes that each site will have unique
characteristics that must be evaluated and compared to those
requirements that apply under the given circumstances. Therefore,
ARARs are identified on a site-specific basis from information
about specific chemicals at the site, specific features of the site
location, and actions that are being considered as remedies.
The following section .outlines: the Applicable or"Relevant and
Appropriate Requirements (ARARs) that apply to. this site.
10.1 Chemical-Specific ARARs
10.1.1 Federal Drinking Water Standards
Section 1412 of the Safe Drinking Water Act (SDWA) . 42 U.S.C.
S300Q-1. "National Water Regulations"; National Primary Drinking
Water- Regulations. 40 CFR Part 141.
EPA has established Maximum Contaminant Levels (MCLs) (40 CFR
Part 141) under the Safe Drinking Water Act (SDWA) to protect
public health from contaminants that may be found in drinking water
sources. These requirements are applicable at the tap for water
provided directly to 25 or more people or which will be supplied to
15 or more service connections. The MCLs are applicable to any
water that would be served as drinking water. Under NCP Section
300.430(f) (5), remedial actions must generally attain MCLs and non-
zero Maximum Contaminant Level Goals (MCLGs) for remedial actions
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NEWMARK Record of Decision 24 August 3, 1993
where the groundwater is currently or potentially a source of
drinking water.
The groundwater at the Newmark OU is a potential source of
drinking water. However, since the Newmark OU remedial action is an
interim action, chemical-specific cleanup requirements for the
aquifer such as attaining MCLs and non-zero MCLGs, which would be
ARARs for a final remedy, are not ARARs for this interim action.
(See NCP, 55 Fed. Reg. 8755.) Nevertheless, EPA has determined
that for the treatment plant effluent from the Newmark OU, the
Federal Maximum Contaminant Levels (MCLs) for VOCs and any more
stringent State of California MCLs for VOCs are relevant and
appropriate and must be attained regardless of the end use or
discharge method for the treated water.
For the treated water which will be put into the public water
supply, all legal requirements for drinking water in existence at
the time that the water is served will have to be met because EPA
considers serving of the water to the public (at the tap) to be
off-site. Since these are not ARARs, these requirements are not
"frozen" as of the date of the ROD. Rather, they can change over
time as new laws and regulations applicable to drinking water
change. See NCP, 55 Fed. Reg. 8758 (March 8, 1990).
10.1.2 State Drinking Water Standards
California Safe Drinking Water Act. Health and Safety Code.
Division 5. Part 1. Chapter 7. §4010 et sea.. California Domestic
Water Quality Monitoring regulations, CCR Title 22, Division 4.
Chapter 15. S64401 et sea.
California has also established drinking water standards for
sources of public drinking water, under the California Safe
Drinking Water Act of 1976, Health and Safety Code Sections
4010.l(b) and 4026(c). California has promulgated MCLs for primary
VOCs. Several of the State MCLs are.more stringent than Federal
MCLs. In these cases, EPA has determined that the more stringent
State MCLs for VOCs are relevant and appropriate for the treatment
plant effluent from the Newmark OU interim remedy. The VOCs for
which there are more stringent State standards include: benzene;
carbon tetrachloride; 1,2-dichloroethane (1,2-DCA); 1,1-
dichloroethene (1,1-DCE); cis-l,2-DCE; trans-1,2-DCE; and xylene.
There are also some chemicals where State MCLs exist but there are
no Federal MCLs. EPA has determined that these State MCLs are
relevant and appropriate for the treated water prior to discharge
or delivery to the water purveyor. The VOCs for which there are no
Federal MCLs but for which State MCLs exist include: 1,1-DCA;
1,1,2,2-tetrachloroethane; and 1,1,2-trichloroethane.
Water served as drinking water is required to meet MCLs at the
tap, not MCLGs. Therefore, EPA would generally not expect a future
change in an MCLG to affect the use of treated groundwater as a
drinking water source. The cumulative hazard index is also not an
ARAR. However, EPA does retain the authority to require changes in
the remedy if necessary to protect human health and the
environment, including changes to previously selected ARARS. See
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NEWMARK Record of Decision 25 August 3, 1993
40 C.F.R. Sections 300.430 ( f) (1) (ii) (B) (1) and
300.430(f)(5)(iii)(C). If EPA receives new information indicating
the remedy is not protective of public health and the environment,
EPA would review the remedy and make any changes necessary to
ensure protectiveness.
EPA has also determined that the monitoring requirements found
in CCR Title 22 Sections 64421-64445.2 are relevant and appropriate
for any treated water which will be delivered to a public water
distribution system. However, the selection of these sections as
ARARs involves only the requirements that specific monitoring be
performed. It would not include any administrative requirements
(such as reporting requirements) and would also not include meeting
substantive standards set within these sections since no such
standards have been identified by the State as being more stringent
than Federal requirements. For the off-site portion of this
remedy, including serving of the treated water, all applicable
requirements would have to be satisfied including the monitoring
requirements in CCR Title 22 Sections 64421-64445.2.
Accordingly, the chemical-specific standards for the
groundwater extracted and treated under the Newmark OU interim
remedy are the current Federal or State MCLs for VOCs, whichever is
more stringent.
10.2 Location-Specific ARARs
No special characteristics exist in the Newmark OU to warrant
location-specific requirements. Therefore, EPA has determined that
there are no location-specific ARARs for the Newmark OU.
10.3 Action-Specific ARARs
10.3.1 Clean Air Act. 42 U.S.C. S7401 et sea.
Rules and Regulations of the South Coast .Air Quality Management
District . , ' . '
The Newmark OU alternative treatment of VOCs by air stripping,
whereby the v'olatiles are emitted to the atmosphere, triggers
action- specific ARARs with respect to air quality.
The Clean Air Act regulates air emissions to protect human
health and the environment, and is the enabling statute for air
quality programs and standards. The substantive requirements of
programs provided under the Clean Air Act are implemented primarily
through Air Pollution Control Districts. The South Coast Air
Quality Management District (SCAQMD) is the district regulating air
quality in the San Bernardino area.
The SCAQMD has adopted rules that limit air emissions of
identified toxics and contaminants. The SCAQMD Regulation XIV,
comprising Rules 1401, on new source review of carcinogenic air
contaminants is applicable for the Newmark OU. SCAQMD Rule 1401
also requires that best available control technology (T-BACT) be
employed for new stationary operating equipment, so the cumulative
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NEWMARK Record of Decision 26 August 3. 1993
carcinogenic impact from air toxics does not exceed the maximum
individual cancer risk limit of ten in one million (1 x 10"5) . EPA
has determined that this T-BACT rule is applicable for the Newmark
OU because compounds such as PCE and TCE are present in
groundwater, and release of these compounds to the atmosphere may
pose health risks exceeding SCAQMD requirements.
The substantive portions of SCAQMD Regulation XIII, comprising
Rules 1301 through 1313, on new source review are also ARARs for
the Newmark OU.
The SCAQMD also has rules to limit the visible emissions from
a point source (Rule 401), which prohibits discharge of material
that is odorous or causes injury, nuisance or annoyance to the
public (Rule 402), and limits down-wind particulate concentrations
(Rule 403) . EPA has determined that these rules are also ARARs for
the Newmark OU interim remedy.
10.3.2 Water Quality Standards for Reinjection and Discharges of
Treated Water to Surface Waters or Land
Federal Standards
The Safe Drinking Water Act provides Federal authority over
injection wells. The Federal Underground Injection Control Plan is
codified in Part 144 of 40 C.F.R and prohibits injection wells such
as those that would be located at the Site from (1) causing a
violation of primary MCLs in the receiving waters and (2) adversely
affecting the health of persons. 40 C.F.R. §144.12. Section
144.13 of the Federal Underground Injection Control Plan provides
that contaminated ground water that has been treated may be
reinjected into the formation from which it is withdrawn if such
injection is conducted pursuant to a CERCLA cleanup and is approved
by EPA. 40 C.F.R. §144.13. These regulations are applicable to
any Newmark OU treated water that is reinjected into the aquifer.
The Resource Conservation and Recovery Act .(RCRA) Section 3020
is also an action-specific ARAR. This section of RCRA provides
that the ban on the disposal of hazardous waste into a formation
which contains an underground source of drinking water (set forth
in Section 3020(a)) shall not apply to the injection of
contaminated groundwater into the aquifer if: (i) such injection is
part of a response action under CERCLA; (ii) such contaminated
groundwater is treated to substantially reduce hazardous
constituents prior to such injection; and (iii) such response
action will, upon completion, be sufficient to protect human health
and the environment. RCRA Section 3020(b).
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NEWMARK Record of Decision 27 . August 3. 1993
State Standards
Rein-jection to Groundwater
For any reinjection to the basin, including spreading, or
discharges to surface water or land that occur on-site, the
reinjected or discharged water must meet all action-specific ARARs
for such reinjection or discharge. The ARAR applicable to the
reinjected water (Alternative 5) is:
• The Santa Ana Regional Water Quality Control Board's
Water Quality Control Plan for the Santa Ana River (and
specific Bunker Hill Sub-basins), which incorporates
State Water Resources Control Board Resolution No. 68-16,
"Statement of Policy with Respect to Maintaining High
Quality of Waters in California." Resolution No. 68-16
requires maintenance of existing State water quality
unless it is demonstrated that a change will benefit the
people of California, will not unreasonably affect
present or potential uses, and will not result in water
quality less than that prescribed by other State
policies.
Temporary Discharges to Surface Water
EPA anticipates that there may be short-term discharges of
treated water to the flood control channel or storm drains during
the initial operation of the VOC treatment plant and on certain
other limited occasions. The ARAR for any treated water that is
discharged, on a short term basis, to surface waters is the
National Pollutant Discharge Elimination System (NPDES) Program
which is implemented by the SARWQCB. In establishing effluent
limitations for such discharges, the SARWQCB considers the Water
Quality Control Plan for the Santa Ana River Basin, Bunker Hill
Sub-basins (the "Basin Plan"), which incorporates Resolution 68-16,
the Inland Surface Water Plan and Temperature Plan for Surface
Waters, and the best available technology economically achievable
(BAT). See. Cal. Water Code § 13263.
Since the RWQCB did not identify specific substantive
discharge requirements or technology standards for such temporary
discharges, EPA has reviewed the Basin Plan (with related
documents) and considered BAT and has made certain determinations
for the short-term discharges to surface waters. In order to
comply with this ARAR, any groundwater that will be discharged, on
a short-term basis, to surface waters on-site must be treated to
meet Federal MCLs or State MCLs for VOCs, whichever is more
stringent.
10.3.3 Secondary Drinking Water Quality Standards
The State of California's Secondary Drinking Water Standards
(SOWS) which are more stringent than the Federal Secondary Drinking
Water Standards shall be ARARs for the Newmark OU if the final use
option involves serving treated groundwater as drinking water. 22
CCR §64471. The-.Calif ornia SOWS are selected as ARARs because they
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NEWMARK Record of Decision 28 August 3, 1993
are promulgated State standards and are relevant and appropriate to
the action of supplying the treated water to a public water
supplier. Although California SDWS are not applicable to non-
public water system suppliers, the California SDWS are relevant and
appropriate since the treated water under this action would be put
into the public drinking water system. Since the Federal SWDS are
not enforceable limits and are intended as guidelines only, they
are not ARARs for this action. Furthermore, since the State SDWS
are more stringent than the Federal SDWS, EPA has not selected the
Federal SDWS as requirements for this action. In summary, if the
treated water is to be served as drinking water, the treated water
at the point of delivery must meet the California SDWS. If the
treated water is recharged or (temporarily) discharged to the flood
control channel, the water will not be required to meet State SDWS.
The Safe Drinking Water Act provides Federal authority over
injection wells. The Federal Underground Injection Control Plan is
codified in Part 144 of 40 C.F.R and prohibits injection wells such
as those that would be located at the Site from (1) causing a
violation of primary MCLs in the receiving waters and (2) adversely
affecting the health of persons. 40 C.F.R. §144.12. Section
144.13 of the Federal Underground Injection Control Plan provides
that contaminated ground water that has been treated may be
reinjected into the formation from which it is withdrawn if such
injection is conducted pursuant to a CERCLA cleanup and is approved
by EPA. 40 C.F.R. §144.13. These regulations are applicable to
any Newmark OU treated water that is reinjected into the
groundwater on the Newmark site.
10.3.4 Resource Conservation and Recovery Act (RCRA) and Hazardous
Solid Waste Amendment (HSWA) Standards. 42 U.S.C. SS6901-6987.
RCRA, passed by Congress in 1976 and amended by the Hazardous
and Solid Waste Amendments of 1984, contains several provisions
that are ARARs for the Newmark OU. The State of California has
been authorized to enforce its own hazardous waste regulations
(California Hazardous Waste Control Act) in lieu of the Federal
RCRA Program administered by the EPA. Therefore, State regulations
in the California Code of Regulations (CCR), Title 22, Division
4.5, Environmental Health Standards for the management of Hazardous
Wastes (hereinafter the State HWCA Regulations), are now cited as
ARARs instead of the Federal RCRA Regulations.
Since the source of the contaminants in the groundwater is
unclear, the contaminated groundwater is not a listed RCRA waste.
However, the contaminants are sufficiently similar to RCRA wastes
that EPA has determined that portions of the State's HWCA
Regulations are relevant and appropriate. Specifically, the
substantive requirements of the following general hazardous waste
facility standards are relevant and appropriate to the VOC
treatment plant for Alternatives 2 through 5: Section 66264.14
(security requirements), Section 66264.15 (location standards) and
Section 66264.25 (precipitation standards).
In addition, an air stripper or GAC contactor would qualify as
a RCRA miscellaneous unit if the contaminated water constitutes
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NEWMARK Record of Decision 29 August 3. 1993
RCRA hazardous waste. EPA has determined that the substantive
requirements for miscellaneous units set forth in Sections
66264.601 -.603 and related substantive closure requirements set
forth in 66264.ill-.115 are relevant and appropriate for the air
stripper or GAC contactor. The miscellaneous unit and related
closure requirements are relevant and appropriate because the water
is similar to RCRA hazardous .waste, the air stripper or GAC
contactor appear to qualify as a miscellaneous unit, and the air
stripper or GAC contactor should be designed, operated, maintained
and closed in a manner that will ensure the protection of human
health or the environment.
The land disposal restrictions (LDR), 22 CCR Section 66268 are
relevant and appropriate to discharges of contaminated or treated
groundwater to land. The remedial alternatives presented do not
include land disposal of untreated groundwater. Because of the
uncertainty in the levels of contamination and volumes of water to
be derived from monitoring and extraction wells at this site, these
waters must be treated to meet Federal and State MCLs for VOCs,
whichever is more stringent, prior to discharge to land. By
meeting the Federal and State MCLs for VOCs before reinjection,
Alternative 5 will satisfy the RCRA LDRs.
The container storage requirements in 22 CCR Sections
66264.170 -.178 are relevant and appropriate for the storage of
contaminated groundwater over 90 days.
On-site storage or disposal of the spent carbon from the
treatment system could trigger the State HWCA requirements for
storage and disposal if the spent carbon contains sufficient
quantities of hazardous constituents that cause the spent carbon to
be classified as a characteristic hazardous waste. If the spent
carbon is determined to be a hazardous waste under HWCA (Sections
66261 and 66262), the requirements for handling such waste set
forth in Sections 66262 and 66268 are applicable.
Certain other portions of the: State's HWCA's regulations are
considered to be relevant but not appropriate to the VOC treatment
plant. EPA has determined that the substantive requirements of
Section 66264.15 (general inspection requirements), Section
66264.15 (personnel training) and Sections 66264.30-66264.56
(Preparedness and Prevention and Contingency Plan and Emergency
Procedures) are relevant but not appropriate requirements for this
treatment system. EPA has made this determination because the
treatment plant will be required to have health and safety plans
and -"operation and maintenance plans under CERCLA that are
substantively equivalent to the requirements of Sections 66264.15,
66264.30-66264.56.
10.3.5 California Water Well Standards.
Substantive standards for construction of public water supply
wells have been published by the State as the California Water Well
Standards. While these standards have not been specifically
promulgated as an enforceable regulation and are therefore not
ARARs, all groundwater facilities designed, located and constructed
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NEWMARK Record of Decision 30 August 3, 1993
to produce drinking water must be constructed in accordance with
these standards. Since the remedy involves delivery of the treated
water to the public supply system, EPA has determined that the
action will comply with substantive Water Well Standards for
construction of water supply wells, such as sealing the upper
annular space to prevent surface contaminants from entering the
water supply. Standards for location of the extraction wells are
not appropriate, since the effectiveness of the remedy is dependent
upon the well locations. Additionally, wells constructed solely
for treatment and reinjection with no delivery to the public supply
system would not be subject to these water well construction
standards.
10.4 Summary of ARARs for the Newmark OU.Interim Remedy
EPA has determined a number of chemical-, and action-specific
ARARs for the Newmark OU interim remedy. All of the alternatives
that involve groundwater extraction and treatment could achieve the
chemical-specific treatment standards for the groundwater at the
point of delivery. However, Alternative 4 which uses an advanced
oxidation process is a less certain technology than liquid-phase
GAC adsorption or air stripping for such a large volume of water
and therefore is somewhat less likely to achieve the chemical-
specific ARARs.
Requirements of nonenvironmental laws, such as California OSHA
regulations (8 CCR 5192) are not considered as ARARs and all such
requirements applicable at the time of the activity would have to
be satisfied.
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NEWMARK Record of Decision 31 August 3, 1993
11.0 THE SELECTED REMEDY
Based upon consideration of the requirements of CERCLA, the
detailed analysis of the alternatives, and public comments, EPA has
determined that Alternative 2: Extraction, Treatment of VOCs by
liquid phase GAC (or air stripping with Best Available Control
Technology for emissions), and Conveyance to a public water
distribution system, in combination with Alternative 5 (as a
contingency): Extraction, Treatment of VOCs, and Recharge to the
aquifer, is the most appropriate interim remedy for the Newmark OU.
Alternative 2 involves grbundwater extraction (pumping) of
8,000 gallons per minute (gpm) in the vicinity of 14th Street,
between Arrowhead and Waterman Avenues, at the leading edge of the
contaminant plume, and an additional 4,000 gpm at the Newmark
wellfield (near 48th Street and Little Mountain Drive) where the
contamination enters the eastern part of the valley. Various
locations and scenarios for extraction wells and rates of
extraction are proposed in the FS report for the Newmark OU;
however, all design decisions for this interim remedy will be made
during the remedial design phase. During the remedial design phase
the locations proposed for extraction wells and scenarios for rates
of extraction per individual well may be selected or new ones may
be selected. The exact number, location and other design specifics
of new extraction wells will be determined during the remedial
design phase of the project to inhibit the migration of the
contaminant plume most effectively. Wherever appropriate, existing
water production wells will be utilized for the remedy, and new
wells will be constructed as necessary, as discussed in the Newmark
OU FS Report.
All the extracted contaminated groundwater shall be treated to
remove VOCs by either of two proven treatment technologies:
granular activated carbon (GAC) filtration or air stripping. EPA
determined during the Feasibility Study (March 1993) that these
treatment technologies are equally effective.at removing VOCs and
are similar in cost at this OU. Both technologies have been proven
to be reliable in similar applications. It is acceptable to use
one technology for the northern (Newmark wellfield) facility and
the other at the southern treatment .facility. Existing treatment
facilities (e.g., the air stripping towers at the Newmark
wellfield) may be modified and incorporated into the remedy as
appropriate. As a result of comments received during the public
comment period, EPA may use a modification of liquid phase GAC
(Advanced Oxidation pretreatment) if this modification proves to be
effective and economical during design phase testing and analysis.
The VOC treatment technology which best meets the objectives of the
remedy for the Newmark OU will be determined during the remedial
design phase, when more detailed information is available to assess
effectiveness and cost.
The treated water exiting the treatment plant shall meet all
MCLs and secondary drinking water standards. If air stripping
treatment is selected, air emissions shall be treated using the
best available control technology (e.g., vapor phase GAC or an
acceptable innovative technology) to ensure that all air emissions
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NEWMARK Record of Decision 32 August 3, 1993
meet ARARs.
The treated water will be piped to the public water supply
system for distribution. Groundwater monitoring wells will be
installed and sampled regularly to help evaluate the effectiveness
of the remedy. More specifically, groundwater monitoring will be
conducted no less frequently than quarterly to obtain information
needed to: 1) evaluate influent and effluent water quality, 2)
determine and evaluate the capture zone of the extraction wells, 3)
evaluate the vertical and lateral (including downgradient)
migration of contaminants, 4) (if the contingency alternative is
implemented) to evaluate the effectiveness of the recharge well
system and its impact on the remedy and 5) to monitor any other
factors associated with the effectiveness of the interim remedy
determined to be necessary during remedial design. Monitoring
frequency may be decreased to less than quarterly if EPA determines
that conditions warrant such a decrease.
EPA has selected Alternative 5 as a contingency if the public
water supply system does not accept any or all of the treated water
(possibly due to water supply needs). Any remaining portion of
water will be recharged into the aquifer via reinjection wells near
the edge of the plume. The number, location and design of the
reinjection wells will be determined during the remedial design
phase to best meet the objectives of the remedy and meet applicable
or relevant and appropriate requirements. With the exception of the
need to meet secondary MCLs and final use of the treated water,
Alternative 5 is identical to Alternative 2 above.
The total duration of the Newmark OU interim remedy will be 33
years, with the first three years for design and construction. EPA
will review this action every five years throughout this interim
remedy period and again at the conclusion of this period.
The VOC treatment plant of the Newmark OU interim remedy
(whether it be Alternative 2, Alternative 5 or a combination.
thereof) shall be designed and operated so as to ' prevent the
unknowing entry, and minimize the possible effect of unauthorized
entry, of persons or livestock into the active portion of the
facility. A perimeter fence shall be erected around the VOC
treatment plant if an adequate fence or other existing security
system is not already in place at the plant site. This fence
should be in place prior to initiation of the remedial action and
should remain in place throughout the duration of the remedy. The
VOC treatment plant shall also be designed and operated so as to
prevent releases of contaminated groundwater from the plant.
The selected remedy for the Newmark OU meets all of EPA's nine
evaluation criteria. The selected remedy is equally effective as
the other alternatives in the short-term and long term reduction of
risk to human health and the environment by removing contaminants
from the aquifer, by inhibiting further downgradient migration of
the contaminant plume, and by reducing the toxicity, mobility and
volume of contaminants in the aquifer.
The VOC treatment technologies selected (liquid phase GAC or
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NEWMARK Record of Decision 33 August 3. 1993
air stripping with best available control technology for emissions)
are technically feasible and proven effective at meeting ARARs for
VOCs in the treated groundwater.
Alternative 2, in combination with Alternative 5, could be
implemented, both technically and administratively.
In a letter dated July 29, 1993, the State concurred with
EPA's selected remedy. EPA received several public comments during
the public comment period, the majority of which expressed support
for EPA's preferred alternative,. These comments, along with EPA's
responses are presented in Part III of this ROD, the Responsiveness
Summary.
The selected remedy is protective of human health and the
environment, meets ARARs, and provides beneficial uses
(distribution to a public water supply and/or recharge) for the
treated water. The selected remedy is cost-effective. The
estimated cost of Alternative 2 has a total present worth of
$49,900,000, which is in the middle of the range for all five
alternatives. The estimated total cost of Alternative 5 .is
$48,100,000.
12.0 STATUTORY DETERMINATIONS
As required under Section 121 of CERCLA, the selected interim
remedial action is protective of human health and the environment,
complies with Federal and State requirements that are legally
applicable or relevant and appropriate to the interim remedial
action, and is cost effective. The selected remedy utilizes
permanent solutions and alternative treatment technologies to the
maximum extent practicable and satisfies the statutory preference
for remedies that employ treatment to reduce toxicity, mobility,
and volume as a principal element.
The selected interim remedial action is protective of human
health and the environment in that it removes significant VOG
contaminant mass from the upper zones of the aquifer and inhibiting
further downgradient and vertical migration of contaminated
groundwater.
The VOC treatment technologies selected (liquid phase GAC or
air stripping with best available control technology for emissions)
are technically feasible and proven effective at meeting ARARs for
VOCs in the treated groundwater and the air.
The selected remedy permanently and significantly reduces the
toxicity, mobility and volume of hazardous substances in the
aquifer as well as the extracted groundwater.
Because this remedy will result in hazardous substances
remaining on-site above health-based levels, EPA shall conduct a
review, pursuant to CERCLA Section 121, 42 U.S.C. Section 9621, at
least once every five years after commencement of remedial action
to ensure that the remedy continues to provide adequate protection
of human health .and the environment.
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NEWMARK Record of Decision 34 August 3, 1993
13.0 DOCUMENTATION OF SIGNIFICANT CHANGES
The only significant change to the Newmark OU interim remedy
proposed in the Proposed Plan fact sheet dated March, 1993,
involves the possible use of a modification to the liquid phase GAC
treatment technology.
As a result of comments received during the public comment
period, EPA further evaluated the use of an advanced oxidation
system as pretreatment for liquid-phase GAC. Additional research
on system effectiveness and revised cost estimates based vendor
reports can be found in the following technical memorandum:
Analysis of "Hybrid" Advanced Oxidation Pretreatroent / Activated
Carbon Alternative for the Newmark Operable Unit (June 25, 1993)
included in the Administrative Record for the Newmark OU.
Pretreatment with a destructive technology has the theoretical
advantage of reducing contaminant mass while enhancing the
operation of a reliable conventional technology. EPA may use this
modification of liquid phase GAC if this modification proves to be
effective and economical during design phase testing and analysis.
The impact of this potential change is that the reliability of
the conventional liquid phase GAC technology is retained and some
desirable destruction of contaminants is realized. Since this
option would only be a modification of the conventional technology,
the advanced oxidation system would not need to be designed to
achieve full treatment of the VOCs, reducing the cost of the
innovative component of the treatment. The cost of operation of
the liquid phase GAC would also be reduced, offsetting a portion of
the increased capital costs.
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