United States
Environmental Protection
Office of
Emergency and
Remedial Response
EPA/ROD/R09-89/028
March 1989
Superfund
Record of Decision:
Fairchild Semiconductor
(S San Jose), CA
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/50272-101
REPORT DOCUMENTATION
PAGE
1. REPORT NO.
EPA/ROD/R09-89/028
3. Racipianf a Acotaalon No.
4. TltWMdSuMN*
SUPERFUND RECORD OF DECISION
Fairchild Semiconductor (S: San Jose),
First Remedial Action - Final
S. Report Oat*
03/20/89
CA
7. Auttlor(a)
S. Partorming Organization Rapt. No.
9> PorfonvtinQ OrQaWNZBtion NHIW mo
10. Pro|acVTaak>Work Unit No.
11. ContncKO or Gr«m
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EPA/ROD/R09-89/028
Fairchild Semiconductor (S. San Jose), CA
First Remedial Action - Final
(
j.6. Abstract (Continued)
•',', -"V-
and ground water still contain high concentrations of chemicals. This ROD provides a
final remedy which addresses ons.vte soil and ground water, and offsite ground water
contamination. The primary contaminants of concern affecting the soil and ground water
are VOCs including PCS, TCA, DCE, and xylenes.
The selected remedial action for this site includes onsite soil vapor extraction
(aeration); onsite shallow ground water and offsite ground water from well RW-25
pumping and treatment using air stripping, followed by offsite reinjection of treated
ground water and discharge to surface water after aquifer reuse capacity has been
exhausted; deep ground water from offsite wells RW2 and RW22, followed by discharge of
untreated ground water to surface water via storm drains; conducting laboratory and
field study of biodegradation of onsite chemicals; implementing institutional controls
including deed restrictions to limit ground water and land use; and ground water
monitoring. The estimated present worth cost for this remedial action is $9,393,100
which includes total O&Mcosts of $7,231,700.
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RECORD OF DECISION
Fairchild Semiconductor Corporation
San Jose, California
February 1989
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T^ \RT.K QF CONTENTS
Part 1 - Declaration V
Part 2 - California Regicnal Water Quality Control Board
Staff Report .v
Part 3 - California Regional Water Quality control Board Site
Cleanup Requirements Order
Part 4 - Responsiveness Summary
Part 5 - Administrative Record Index
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PART 1
DECLARATION
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l^CORD OF DECISION
DECLARATION
SITE NAME AND LOCATION:
Fairchild Semiconductor Corporation
San Jose, California
STATEMENT OF BASIS AND PURPOSE
This document serves as EPA concurrence with the remedial
action for the Fairchild Semiconductor Corporation (Fairchild)
site in San Jose., as approved by the California Regional Water
Quality Control Board, San Francisco Bay Region (RWQCB). The
RWQCB approved this remedial action in conformance with §13000
and §13304 of the California Water Code, State of California
Health and Safetr Code §25356.1, CERCLA, as amended by SARA, and
the National Contingency Plan.
This EPA concurrence with the State's selection of remedy is
based upon the RWQCB's Staff Report, the Remedial Action Plan,
the Site Cleanup Requirements Order, the Responsiveness Summary,
and the Administrative Record for this site. The attached index
lists the items comprising the Administrative Record.
DESCRIPTION OF REMEDIAL ACTION
The selected remedy provides fci final cleanup requirements
related to onsite soils and groundwater, and offsite groundwater
contamination. Fairchild has conducted interim remedial ac-
tivities under RWQCB orders since 1982. In 1986, the Company in-
stalled a slurry wall around the entire property and keyed it
into the first competent a^uitard below the site, containing the
highest levels of contamination within the onsite area. The major
components of the final selected remedy include:
o Onsite.soil vapor extraction
o Onsite shallow -groundwater extraction and treatment with
airstripping
o Reinjection of all onsite, and some offsite treated
groundvater
o Offsite deep groundwater extraction and air stripping
with nozzles into storm drains
o Discharge to surface water under NPDES permit of any
treated groundwater remaining after reuse capacity has
been exhausted
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DECLARATION '|L
EPA concurs with the remedy selected by the RWQCB for the
Fairchild site. 1 £
The selected remedy*is protective of.human health and the
environment, attains Federal and state requirements that are ap-
plicable or relevant and appropriate to the remedial action, and
is cost effective. This remedy satisfies the statutory
preference for remedies that reduce toxicity, mobility, and/or
volume as a principal element. It also utilizes permanent solu-
tions to the maximum extent practicable. The 5-year facility
review provision has been included as part of the RWQCB Site
Cleanup Requirements Order.
3. 20. 8
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PART 2
STAFF REPORT
6
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REGIONAL WATER QUALITY CONTROL BOARD
8AN FRANCISCO BAY REGION
INTERNAL MEMO
Steven R. Ritchie, Ex.cutive Officer ElUabeth Cameron.
- ; PBOM Aj.oe. WRCE
DATE: J>nUary 5' "89 SIGNATURE: -
SUBJECT: STAFF REPORT
FINAL CLEANUP PLAN FOR FAIRCHILD SEMICONDUCTOR CORPORATION
SAN JOSE FACILITY
Since 1981, Fairchild Semiconductor Corporation has been Investigating and
cleaning up soil and groundvater pollution at their San Jose facility. Due to
the risk to human health and the environment, the Fairchild-San Jose site was
proposed for inclusion on the federal Superfund list in 1984.
The Regional Board has previously adopted sevoral Orders concerning the pollution
at this sice. In November 1982, the Regional Board issued an NPDES permit for
the discharge of polluted groundwater (Order Ho. 82-61). Site Cleanup
Requirements were adopted in August 1986 (Order No. 86-62), revised in March 1987
(Order No. 87-16), and amended in March 1988 (Order No. '88-46). Regional Board
Order 87-16 required Fairchild to submit a final cleanup plan for the site.
Subsequently, Fairchild submitted a revised Remedial Action Plan (RAP) on October
7, 1988. Regional Board staff have reviewed this RAP and drafted the attached
Site Cleanup Requirements (SCR) for regulating final cleanup of the site and
Waste Discharge Requirements (WDR/NPDES permit) for relnjection or reuse of the
extracted groundwater and/or discharge of the extracted groundwater to Canoas
Creek. This staff report provides background Information on and staff's
rationale for the recommended SCR and NPDES permit.
The Tentative Orders were officially available for public comment from November
8 through December 8, 1988. The SCR and NPDES permit have been revised to
address comments received during the public comment period.
BACKGROUND
-Site Location and Description. Fairehild has owned property at 101 Bernal Road
in San Jose.since 1975 (Figure 1 - Site Location). Fairchild operated a semi-
conductor manufacturing facility at the site from April 1977 until it closed in
October 1983. The facility has been inactive since 1983.
In November and December 1981, Fairchild discovered that an underground organic
solvent waste tank had failed, releasing a mixture of solvents to the «ubsurface.
A public drinking water supply veil. Great Oaks Water Company wall number CO-
13, located approxisuttely 1800 feet down-gradient from the site, was contaminated
by the release, causing a risk to public health. TCA concentrations of 5,700
ppb entered the well while it was being used as * drinking water supply well;
the drinking water standard for TCA is 200 ppb. CO-13 was removed from service
on December 7, 1981, as soon as the contamination was detected, and has since
been destroyed and sealed.
376A <4/75)
ZHOU
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January ~i»7~iui'.i'"5r
fTAJT 1X7 O.T
In 1987, all issued and outstanding shar*s of Pairehild stock vere sold be
Schluaberger Technology Corporation to latlonal Semiconductor Corporation.
Following the sale, Schluaberger retained all environmental liabilities
associated vith its past activities at the site. Schluaberger is currently
managing the cleanup on behalf of Fair child. Schluaberger has entered into a
contract to sell the 22 acre site to the Roll Coapany. Koll plans to develop
the property as a neighborhood shopping center.
Subsurface Investigation. Fairchild has drilled aore than 239 soil borings and
installed over 124 groundvater monitor ing and extraction veils in order to define
and contain soil and groundvater pollution froa their San Jose facility. Three
aquifers, designated the A, B, and C aquifers, have been contaminated vith
organic solvents. The A aquifer is first encountered at depths of 10 to 20 feet
belov the ground surface and a -tends to depths of up to 60 feet. The A aquifer
is not continuous off-site and is currently generally devatered. The B aquifer
is generally located between (Depths of 60 and 120 feet belov ground surface.
The C aquifer is generally found between 150 and 190 feet belov ground surface;,
Only trace levels of cheaicals have ever been detected belov the B aquifer on
site or belov the C aquifer oi ?-site. '
The following chemicals are the priaary pollutants that have been detected is:
soils and groundvater on-site (vithin Fairchild's property boundaries):
1. 1.1-,1-trichloroethane (TCA),
2. 1,1-dichloroethene (DCE).
3. Isopropyl alcohol (1PA),
4. Xylenes,
5. Acetone,
6. l,l,2-trichloro-I,2,2-trlfluoroethane (Freon-113) , and
7. Tetrachloroethene (PCE).
Past and current cheaical concentrations detected in on-site groundvater are
listed in Table 1.
Off-site, cheaicals have been detected In groundvater to a depth of 190 feet
belov ground surface. TCA, DCE, and Ft eon-113 are the cheaicals that have been
detected off-site, vith TCA being detected most frequently and in the highest
concentrations. Off-site cheaical concentrations are listed in Table 2.
Interim Actions. Interim actions taken by Fairchild since the discovery of the
release in 1981 include:
1, SOURCE REMOVAL AND SOIL CLEANUP - Actions taken to prevent further solvent
aigration froa the source area include removal of the defective tanV; and
excavation of 3,389 cubic ya£ds of on-site soil containing an estimated
38,000 pounds of cheaicals. Past and current concentrations detected in
on-site soils are listed in Table 3. Off-site soils were not directly
effected by the Fairchild release, although cheaical residuals aay remain
in soils that have been or are effected by the' groundvater pluae.
2. SOIL-BENTONITE SLURRY WALL • In 1986 Fairehild installed a 3-foot thick
slurry vail around the perimeter of their property. The slurry vail is
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__ January 5, 1989
,r RAIT EXTORT C,
keyed into the^BC aquitard. By installing the slurry vail and establishing
sn inward gradient by pumping small amounts of groundvatar within the
confines of t&a slurry vail, Fairchild has minimized further migration of
. on-site cheaicals into off-site groundvater. 1
3. PILOT STUDIES - Fairchild has conducted on-site pilot studies to determine
the effectiveness of on-site aquifer flushing and in-eitu soil aeration
in cleaning up on-site groundvater and soils. On-site flushing vas
determined to be ineffective in removing cheaicals froa the A aquifer.
In-situ soil aeration is a technique for removing volatile cheaicals by
applying a vacuua on the polluted soils. This technique vas determined
to be effective in removing volatile chemicals froa on-site soils.
4. MIGRATION CONTROL AND GROUNDVATER CLEANUP - Through the use of groundvater
extraction veils, the plume has been under hydraulic control since 1982.
Fairchild's groundvater extraction program has reduced the length of the
pluae froa 4,900 feet in October 1982; to approximately 2400 feet in
September 1988 (Figure 2). The maximum concentration of TCA detected off-
sitt?? has been reduced to 430 ppb (9-12-88 data). As cleanup has
A. progressed, Fairchild has been able to reduce their pumping rate froa a
maximum of 9217 gpm (14,870 AF/yr) in February 1984 to 1042 gpa (1680
AF/yr) as of September 1988. Fairchild's groundvater extraction program
has removed approximately 90,000 pounds of chemicals (75,000 pounds from
on-site groundvaters and 15,000 pounds from off-site groundvaters).
5. CROUNDUATER TREATMENT - Since 1982 Fairchild has been discharging the
extracted groundvater through storm drains to Canoas Creek under an NPDES
permit. Considering that discharge concentrations from most parts of the
plume are veil belov vater quality standards, the original NPDES permit
allowed the bulk of the extracted groundvater to be discharged to Canoas
Creek vithout treatment. Groundvater extracted on-site and from ff-site
veil RV-25 is treated using air stripping prior to discharge.
6. GROUNDWATER CONSERVATION - Groundvater polluted by the Fairchild release
is part of the Santa Teresa groundvater basin. Low rainfall, reduced
efficiency in artificial recharge ponds, and pumping for vater supply and
aquifer remediation have caused declines in the groundvater levels in the
Santa Teresa Basin. Considering these vater level declines, the very lov
" levels of cheaicals in the C aquifer (< S ppb), and that pumping from the
C aquifer for discharge to Canoas Creek may be a vas-te or unreasonable use
of vater, the Regional Board issued Order 88-46 in March 1988. This Order
allowed Fairchild to implement a phased vater conservation program in the
. C aquifer. ;~As a result of this vater conservation program, Fairchild
(..^eliminated all groundvater extraction froa the C aquifer on September 6,
*"7l988.
RISKS POSED BY THE RELEASE
-The 1981 release of contaminants to the subsurface created a significant risk
to human health and the environment. The primary threat vas to the public
through the consumption of drinking vater containing chemicals greatly in excess
of DHS drinking vater action levels. This immediate threat vas eliminated by
removing drinking vater supply veil GO-13 from service and by containing the
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—' January 5.
STAFF
plume so'i^hat other drinking water •upplyr*ells were not contaminated by the
release. ^
Interim e|eanup actions have significantly decreased both the sixe of the plume
and the concentrations within the plume; hontver, some areas of the plume outside
the slurry wall currently contain concentrations of chemicals in excess of DHS
drinking water action levels. A potential threat to the public would exist if
nev drinking water supply wells were installed in these areas. A well permit
must be obtained froa the Santa Clara Valley Vater District (SCVWD) to install
wells in the vicinity of the Fairchild plume. The SCVWD has a policy of advising
against installing wells in areas known to contain chemicals, even when
concentrations are belov health standards.
The slurry wall has ainiaized the migration of chemicals located on-site into
off-site aquifers by minimizing groundvater flow from the on-site aquifers. This
has greatly benefitted the off*site cleanup; however, high concentrations of
chemicals remain in on-site soils and groundvater. Groundwater concentrations
on-site are significantly in exiess of health criteria; consequently, on-site
aquifers cannot currently be used as a source of drinking water. (Current
chemical concentrations on-site and their respective drinking water standards
are listed in Table 1.)
There are several drinking water supply wells located down-gradient from the
release. If cleanup activities were stopped today and assuming the slurry vail
vas effective in minimizing the concentrations of on-site chemicals migrating
into off-site aquifers, TCA concentrations up to 13 ppb may reach five existing
drinking water supply wells. These concentrations are well belov the DHS
drinking water action level of 200 ppb for TCA.
If cleanup activities were stopped today, chemicals off-site would also spread
through a larger are' of the subsurface. With time, n-site chemicals vould
begin to slowly dgrate through the slurry wall. Dilution and potential
degradation voul'V reduce the concentrations in th< aquifers off-site although
a larger area of the environment would be effected.
Risks te yublic health and the ettvironsH.it. due to air emissions, chemicals
entering surface waters, or exposure to vurface soils are minimal.
DEVELOPMENT OF REMEDIAL ACTION PLAN
Regional Board Order 87-16 required Fairchild to submit a report evaluating the
effectiveness of interim cleanup and analyzing alternatives for final remedia-
tion of the cite. Fairchilu has subsequently submitted and revised a draft
Remedial Action Plan (RA?). Regional Board staff have determined that the
technical information contained in the revised RAP submitted October 7, 1988,
is acceptable for developing a final cleanup plan for the site. In making this
determination, staff did not accept the portions of the RAP addressing: (1)
-Applicable or Relevant and Appropriate Requirements (ARARs), and (2) the NPDES
permit. These areas are addressed in the Addendum to the RAP dated December 16,.
1988, prepared by agency staff, and included as Attachment 1 of this staff
report. Differences between staff's recommended cleanup plan and Fairchild's
recommended cleanup plan are discussed in this staff report.
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_ January 5. 1989
flATF UPOH ^
•i.n*
The Pairchild-San Jose facility la proposed for Inclusion on the federal
Superfund list. Consequently, the adopted BAP and the Regional Board'a actions
in the SCR must fulfill: (1) Che requirements of Che Comprehensive atevironaental
Response, Compensation, and Liability Act (CZRCLA) aa amendad tjy the Superfund
Aaendaent and Reauthorixation Act (SARA). (2) the Rational Contingency Plan (NCP)
requirements for a remedial investigation and feasibility study (II/FS), and (3)
Health and Safety Coda Section 25356.1 requirements for a remedial action plan.
To ensure compliance with these lavs and regulations. EPA and DHS staff have also
reviewed and commented on the RAP.
Hazard Indices. Fairchild evaluated a variety of groundvater cleanup levels
using Hazard Indices (His). Whereas drinking water standards are developed for
each individual chemical, the HI is a method for assessing the public health risk
associated with exposure to multiple chemicals. An HI equal to 1 indicates that
all chemicals are at or below national Kq*l*»™ Contaminant Levels (MCLs) for
drinking water. DHS drinking water action levels fop the chemicals of concern
at the Fairchild site are equal to or more stringent than MCL's. Therefore, DKS
drinking water action levels, rather than MCLs, have'been used in calculating
His for the Fairchild-San Jose site. In the RAP, the HI for non-carcinogenic
compounds is calculated as shown below.
n
S concentration of chemical *i" in the yroundvater
DHS drinking water action level for chemical "i"
Since only TCA and DCE are currently detected in the off-site aquifers, the off-
site HI can be calculated as follows:
cone. of TCA (•ovib) ^ cone of DCE f-ppbV - HI for off-site
200 ppb TCA 6 ppb DCE " aquifer
The values for MCLs or DHS action levels may increase or-decrease based on
information obtained in the future. If these values change, the Hazard Index
must be recalculated to reflect the changed values.
His are usually calculated separately for potential carcinogenic chemicals and
non-carcinogenic chemicals. There are no known potential carcinogenic chemicals
in off-site groundvater s. One potential carcinogen, PCE, has been detected on-
site. -Since only one potential carcinogen has been detected on-site and none
have been detected off-site, Hazard Indices have been calculated only for non-
carcinogenic chemicals. The maximum on-site Hazard Index for the carcinogenic
compound is 21.3 (PCE is present on-site at a maximum concentration of 85 ppl*).
In the RAP, cleanup goals and alternatives are evaluated separately for the on-
site and off-site areas due to the presence of the slurry wall ,«nd the
differences in types, locations, and concentrations of chemicals on-site and off-
site. On-site and off-site cleanup alternatives are summarized in this staff
report. oA more detailed description and evaluation of these alternatives is
included in Fairchild's RAP submitted October 1988.
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January j, .^iiu
1 i
RAFT WOET
.V'.;.
OFF-SITE CLEANUP
••£,-!
Off-lite cleanup levels. Fairehild evaluated alternatives that will mchieve|
cleanup to the following levels off-site: 7 \.,
1. EXISTING CONDITIONS. Thi« cleanup level would allow the lo«« of beneficia^
uaes (as defined in the San Francisco Bay Basin Plan) at the well head anc^
in the off-site aquifers. The maximum HI off-site is approximately 2 in
the B aquifer. Hazard indices in the C aquifer are below 0.025.
2. HAZARD INDEX - 1.0. All off-site aquifers would be cleaned up to at lease
current DHS drinking water action levels. It is estimated that this
cleanup goal could be achieved within 1 year.
3. HAZARD INDEX - 0.25. All off-site aquifers would be cleaned up to a level
at least four tines more stringent than current DHS drinking water action
levels. It is estimated this cleaz>vp goal could be reached in 5 years.
• fi
4. RESTORE TO BACKGROUND. To achieve this cleanup level, concentrations of
all pollutants in all off-site aquifers would be reduced tc^below lab-
oratory detection levels. Fairehild has estimated the length of tine
required for cleanup to this level to be 14 years; however, it may noc be
technically possible to reach this cleanup goal. Because of the potential
technical infeasibility and considering the estimated amount of groundvater
extraction required to achieve this cleanup level (18,000 acre-feet
compared to 2.200 acre-feet to reach an HI of 0.25), detailed cleanup
alternatives were not developed for this cleanup level.
(In response to public comment and staff's subsequent request, Fairehild also
evaluated the time required and amount of groundvater that would be extracted
to achieve a Hazard Index of 0.10.)
Off-site cleanup alternatives. Fairehild developed detailed analyses of 7 off-
site cleanup alternatives. Costs for each off-site alternative are presented
in Table 4.
Alt.l NO FURTHER ACTION. In this alternative, currant groundvater extraction
would be terminated. Groundvater monitoring would be continued to asses?
changes in the extent of and concentrations in the plume. It is anti-
cipated that detectable levels of chemicals could reach existing drinking
water supply wells within six months to 5 years. Concentrations in all
existing drinking water supply wells would reaain well below the DHS
drinking water action level of 200 ppb TCA. Of the five drinking water
supply potentially effected by ti.e Fairehild pluae. Great Oaks well GO-A
would receive the highest TCA concentrations (up to 13 ppb).
Alt.2 GROUNDUATER EXTRACTION AND DISCHARGE TO O&HOAS CREEK. This alternative
is essentially a continuation of the interim off-site grour.* ater
extraction program with the addition of nozzle aeration. Groundvater
would continue to be extracted from the B aquifer with the rate of
extraction decreasing as the plume recedes. The groundvater extracted from
most wells would pass through nozzles to aerate the water and reduce the
concentration of volatile compounds prior to discharge through storm drains
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January 5. 1989
STAFF BXFOKT
5s.
to Canoas Creek. Hozzle treatment should reduce the concentration of
volatile compounds (primarily TCA) by 10-50 percent. Croundvatar from off-
sita well RV-25 would be piped on-»ite and treated using Air stripping
. prior to discharge. ,'•"
Alt.3 CROUNDUATER EXTRACTION, TREATMENT TO 5 PPB, AND DISCHARGE TG^COYOTE CREEK
PERCOLATION PONDS. As In Alt. 2. groundvater extraction froa the B aquifer
would continue. Alt. 2 and 3 differ in that Alt. 3 contains a water
conservation »easure and more effective and costly groundvater treataent.
All extracted groundvater would be treated using air stripping to reduce
concentrations of each volatile organic cheaical to below 5 ppb. The
treated water would then be piped to the Coyote Creek percolation ponds
to provide groundvater recharge.
Alt. 4 GROUNDUATER EXTRACTION, TREATMENT TO 5 PPB. AND RE INJECTION. Groundvater
. extraction and treataent is the saae in this alternative as in Alt. 3.
| The difference is in the method used for water conservation. In this
o alternative, groundvater recharge would be enhanced through the direct
f reinjection of the treated groundvater into the off-site B aquifer.
Alt.5 GROUNDUATER EXTRACTION, TREATMENT TO S PPB, AND DISCHARGE TO CANOAS CREEK.
This alternative is the saae as Alt. 2 except that all groundvater would
be treated using air stripping to meet discharge limits of 5 ppb for each
volatile organic cheaical prior to discharge to Canoas Creek.
Alt.6 GROUNDUATER EXTRACTION AND DISCHARGE TO SANTA TERESA GOLF COURSE IRRIGATION
POND. The groundvater extraction program in this alternative is the same
as that in Alt. 2 through 5. On a seasonal basis, the extracted ground-
water would be piped to the Santa Teresa Coif Course irrigation pond.
Irrigation would consume all extracted groundvater for 9 months each year.
During the other 3 months, the excess groundvater would be discharged after
nozzle aeration to Canoas Creek.
Alt.7 GROUNDUATER EXTRACTION AND DISCHARGE TO CANOAS CREEK WITH OFT-SITE
REINJECTION OF CROUNDVATER TREATED AT THE OH-SITE TREATMENT SYSTEM. This
alternative is identical to Alt. 2 axcept that groundvater froa off-site
«* well RU-25 and groundvater extracted on-site would be treated using air
'v stripping .and then reinjected outside the slurry wall. In Alt. 2, this
'£•' water is treated and then discharged to Canoas Creek.
Vlth the exception of Alt. 1 (No Action), each alternative is capable of
achieving a cleanup level of HI-1.0 or HI-0.25, depending on the'length of time
groundvater extraction continues. Groundvater quality in the C aquifer is
currently well belov an HI of 0.25. Therefore, off-site pumping for any
alternative would be required only in the B aquifer to achieve an HI of 0.25.
In -the £ aquifer, either cleanup goal is expected to be achieved Most quickly
in areas furthest down-gradient froa the original source of pollution. The plume
has therefore been divided into the three zones shown in Figure 3. The estimated
cleanup time for each zone and the total volume of water to be extracted from
the B aquifer are as shown in Table 6. This information is also presented
graphically at the bottom of Figure A.
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RAIT 1XFORT
| OH-SITE CLEANUP '•*?
a • **?
5;
On-site cleanup alternatives. Fairchild developed detailed analyses of 6 on*
cite cleanup alternatives. Costs for oaeb on*site altiraative are •umaarized
' In Table 5. J4
Alt.l NO FURTHER ACTION. In this alternative, the extraction of groundwater from
on-site veil VCC-20(B) would be discontinued and no further soils treataent
would be conducted. Groundvater quality and groundvater level monitoring
would be continued to detect migration of chemicals from within the slurry
wall boundaries.
Alt.2 ACHIEVE AND MAINTAIN AN INWARD HYDRAULIC GRADIENT ACROSS THE SLURRY WALL.
On-site Alt. 2 involves long-term punping of groundvater from within the
slurry wall. If no groundvater is pumped within the slurry wall, ground-
water containing chemicals would slowly migrate through the slurry wall
into off-site aquifers. Pumping with!;} the slurry wall would limit the
migration of on-site eheaicals to olj-site aquifers. The extracted
groundvater would be treated using air Stripping prior to reuse, reinjec-
tion, or discharge to Canoas Creek.
Alt. 3 IN-SITU SOIL AERATION OF THE A AQUIFER AND AB AQUITARD IN AREAS WITH TCA
CONCENTRATIONS GREATER THAN 10 PPM AND IN-SITU SOIL AERATION OF THE B
AQUIFER. . In this alternative, 37 air extraction wells (similar to water
extraction wells but Installed above the water table) would be installed
in on-site soils polluted with greater than 10 ppa TCA. A vacuum vould
be applied to the air extraction veils to draw volatile chemicals out of
the soil. The chemical-laden air would pass through an activated carbon
system prior to being discharged to the atmosphere. Partial devatering
of soils in the B aquifer vould be required for the aeration system to be
effective in deeper soils.
£airchild proposes to operate the in-situ soil aeration system In soils
vith greater than 10 ppm TCA until the chemical removal rave from each air
extraction veil has decreased to 10 percent of the initial removal rate
or the removal rate is declining at a rate of less than 1 percent per day
over a 10 day period. The objective of this alter.acive would be to reduce
on-site chemical concentrations to maintain »u off-site HI of 0.25.
Fairchild anticipates operating the system for 6 months in the A aquifer
and AB aquitard and 1 year in the B aquifer. The system.is expected to
remove 12.000 pounds of chemicals in 6 months, at which time the highest
average TCA concentration in the soil would be approximately 200 ppm. The
expected Hazard Index would be approximately 10.
Alt. 4 IN-SITU SOIL AERATION OF THE A AQUIFER AND THE AB AQUITARD IN AREAS WITH
TCA CONCENTRATIONS GREATER THAN 1 PPM AND IN-SITU SOIL AERATION OF THE B
AQUIFER. This alternative uses the same treatment described in Alt. 3
applied to a larger area of polluted soil. Soils with greater than 1 ppm
TCA would be treated using 61 air extraction wells. The «ystem would be
operated until the chemical removal rate decreases to the point described
in Alt. 3. Fairchild anticipates operating the system for 6 months to
remove ah estimated 12,100 pounds of chemicals. This alternative would
also maintain an off-site HI of 0.25.
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__ January 5. 1989
KAJF UPORT
Alt.5 IN-SITU SOIL AERATION OF THE A AQUIFER, TOSATURATED B AQUIFER. AND THE
AQUITARD IN AREAS VITH TCA CONCENTRATIONS GREATER THAN 10 PPH AND CTQUND- ,,
WATER FLUSHING OF THE SATURATED B AQUIFER TO AN HI-1.0. In this altam*- :
tive, in-situ aoil aeration would be combined with groundwatar flushingif
of the aaturated B aquifer to achieve an HI-1.0 en-cite. Croundwater
flushing would be accomplished by extracting groundvater on-aite and from
two off-site up-gradient wells (as necessary) and reinjecting the combined
flov into the on-aite B aquifer. The water would be treated using air
stripping prior to reinjection into nine on-aite wells. The in-situ soil
aeration system would be operated until TCA concentrations in the soil are
reduced to 10 ppm. It is expected that groundvater flushing at up to 250
gpm would continue for up to 6 years.
Alt.6 IN-SITU SOIL AERATION OF THE A AQUIFER, THE UNSATURATED B AQUIFER, AND THE
AB AQUITARD IN AREAS WITH TCA CONCENTRATIONS GREATER THAN 1 PPM AND
CROUNDWATER FLUSHING OF THE SATURATED B AQUIFER TO AN HI-0.'
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-' , JLi-'iiu
RAFF REPORT
4. The plan effectively reduces chemical concentration* on-*it» to *j level that
will ensure compliance with the off-site cleanup goal of '2tl«0.2Sft;'
•*? ^
5. The plan effectively removes chemicals from off-site aquifer*. |/
STAFF CONCERNS WITH FAIRCHILD'S PROPOSED PL/U
The cleanup plan proposed by Fairchild does not completely satisfy staff
concerns.
1. Groundvater Conservation. Fairchild's plan relies on the sequential shut
down of extraction wells as the boundaries of the plume recedes for
groundwater conservation. (Reuse measures may also be employed, but final
measures have not yet been presented to staff.) Regional Board staff agree
that groundwater conservation measures are limited for the Fairchild cleanup.
Groundwater extraction is expected to continue for 5 y»irs; however, the bulk
of the extraction (560 gpm out of a total anticipated -extraction of 610 gpa)
is expected to be curtailed in 2 years. Fair child anticipates that it would
take 9 to 16 months to implement treatment and re Inject'.on/reuse alternatives
for conserving groundwater. Therefore, permanent reuse measures appear
unwarranted for the groundwater that will only be extracted for 2 years.
Intermittent reuse (e.g., for construction purposes or local irrigation) may
be possible.
Groundwater, will be extracted from off-site well RV-25 and possibly from on-
site wells'for the entire 5 years. Regional Board staff believe reinjection/
reuse facilities are warranted for this part of the extraction and have
incorporated a partial reinjection element into staff's proposed plan
(described below). Fairchild opposes partial reinjection because of: (1)
potential clogging of reinjection wells, (2) potential migration of pollutants
into new areas of the aquifer, and (3) cost. Regional Board staff dr not
expect (1) and (2) to be significant problems due to the low flow rs.ce and
the low concentrations of chemicals that would be injected. Furthermore,
these concerns can be evaluated in a short term study. The increase in cost
($419,700) to reinject this amount of water (480 acre-feet) is not significant
compared to the anticipated total cost of cleanup of $38,000,000-
2. On-site Groundvater Cleanup Levels. Fairchild's proper id plep for on-site
cleanup would result in an estimated HI of 10 in on-site aquifers. Regional
Board staff believe lower levels are warranted and feasible. In addition to
the potential for off-site migration of chemicals within the slurry wall,
groundwater contained within the boundaries of the slurry wall i* a potential
•ource of drinking water. MCLs must be achieved or potential sources of
drinking water. (Exceptions to attaining MCLs #re discussed on p*ge 16.)
Fairchild'* recommended plan would establish on-efti ci&3aup levels to
maintain an HI of 0.25 outside the slurry wall. Considering that slurry walls
have only been constructed during the past 50 years (a short time compared
to the length of time off-cite aquifer protection wouldbe required) , reliance
on the »lurry wall for containment of chemical* should be minimized. Regional
Board staff are also concerned that use of the slurry wall as a permanent
cleanup technique to contain on-site chemicals effectively creates a 22-acre
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, , . ,, — January 5. 1989
' •••••'•'•', •••}••, •. •.•/.. <•:!*'''i'. J1;-/! ''
RAJ? ixpoM
hazardous'waste disposal area. Every reasonable effort should be made'-tto
reaove chemicals from on-site soils and groundvater and to restore on-site
aquifers to drinking water quality. \:
3. Operation of the In-situ Soil Aeration System. Fairchild proposes to operate
the in-situ soil aeration system in soils with greater than 10 ppa TCA until
the chemical removal rate from each air extraction well has decreased to 10
percent of the initial removal rate or the removal rate is declining at a
rate of less than 1 percent per day over a 10 day period. The system would
be operated for an estimated 6 months. If this criteria is used for
terminating operation of the in-situ aeration system, the actual concentra-
tions of chemicals remaining in the soil will not be known. In the cleanup
plan developed by Regional Board staff (discussed below), an actual soil
cleanup goal is established.
Regional Board believe that in-situ aeration is feasible and .warranted in
soils with greater than 1 ppm TCA, rather than only in soils with greater than
10 ppa TCA as proposed by Fairchild. The pilot in-situ aeration system
operated in 1987 effectively removed an average of 8 pounds of chemicals per
day from an air extraction well located near the 1 ppa TCA boundary.
Additionally, Fairchild acknowledges that the most critical parameter
affecting groundvater concentration levels on-site is the total chemical mass
remaining when cleanup activities cease. Regional Board staff also believe
the in-situ soil aeration system should be operated for longer than 6 months
if the additional operation will facilitate achieving and maintaining drinking
water action levels on-site.
STAFF'S RECOMMENDED FINAL CLEANUP PLAN
Regional Board staff have developed a final cleanup plan that addresses the
concerns discussed above. The plans recommended by Regional Board staff and by
Fairchild contain many common elements. Both recommend: (1) continued ground-
water extraction off-site until an HI of 0.2S is achieved, (2) the addition of
nozzle aeration for off-site discharge to Canoas Creek, (3) the use of in-situ
soil aeration for cleaning up on-site soils, and (4) a biodegradation study for
the on-site area. Specific elements of the staff's proposed plan are discussed
below.
Development of the proposed plan was based on the RAP and on the Regional Board's
evaluation of seven years of water and soil quality data.- Samples have been
collected and analyzed by the Regional Board to confirm the -validity of data
generated by the discharger. Some of the data were also reviewed by EPA and
found to be acceptable for limited purposes. The quality of the available data
has been taken into consideration in developing the proposed final plan.
The possibility, exists that the final remediation plan will be more effic.'-vit
and rapid than expected. If that is the case, additional cleanup may be
appropriate for Regional Board consideration at a later date to comply with the
State Board policy to maintain the high quality of waters In the State of
California.
OFF-SITE CT.FAKyp Regional Board staff recommend that Alternative 7 (Croundvater
Extraction and Discharge to Canoas Creek with Off-site Reinjection of Groundvater
11 .-:-
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January j, „. 4i
RAVT 11XHLT
Treated at the On-site Treatment System) be implemented for off-site cleanup to
an HI of 0.25. This cleanup plan would entail the following: ';>
1. ffroundvater Extraction. Groundwater would continue to be extracted froa off-
site B aquifer wells RV-2, RW-22, and RW-25 at en initial eombixttd rate of
roughly 610 gpa (984 AT/yr). It is expected that wells BV-2 sad 3JJ-22 would
only be needed for 2 years, after which time off-site extraction would be
limited to well RV-25.
It is not certain that, once extraction from B.V-2 end RW-22 is curtailed,
extraction from RV-25 will effectively remove chemicals froa all parts of the
plume containing chemicals above a Hazard Index of 0.25. Therefore,
piezometers may be required to determine capture cones for off-site cleanup.
Additional extraction wells may be required in the future to ensure that
chemical concentrations throughout the plume are reduced to achieve an HI of
0.25.
Jt
V-
Additional monitoring wells are also proposed to determine plume boundaries
in the area bounded by the following streets: Bernal R*ad, Via del Oro, Great
Oaks Blvd. and Santa Teresa Blvd. (See Figure 2.) *'
2. Groundvater Treatment and Disposal. Groundwater extracted from RW-25
(approximately 50 gpm) would be piped on-site for air stripping treatment
prior to reinjection off-site. Existing wells located outside the slurry
wall would be used for reinjection. Groundvater from other off-site wells
(approximately 560 gpa) would to be discharged after nozzle aeration to Canoas
Creek. Treatment levels required for discharge will be regulated under an
NPDES permit. This permit is discussed on page 14.
3. Final Groundvager Cleanup Level. Cleanup activities would continue until an
HI of 0.25 has been achieved off-site. This is expected to take 2 years
except for the part of the plume controlled by RV-25. Groundvater would be
extracted from this well for an estimated 5 years. Extraction wells voulc"
be sequentially shut down as cleanup goals are achieved in each part of the
plume.
There is a difficulty with relying solely on achieving an HI *»C 0.25 for
determining final cleanup. Based on the current ratio of TCA to X2, DCE must
be reduced to 0.75 ppb and TCA must be reduced to 25 ppb to ,-^ach an HI of
0.25; however, DCE cannot be detected below approximately 1 ppb with current
laboratory detection limits. If it is assumed that a chemical is not present
when it cannot be detected by laboratory analysis, Fairchild would only be
required to reduce DCE concentrations to below 1 ppb and TCA concentrations
to below 50 ppb to achieve an HI of 0.25. Therefore, a second cleanup
criterion is proposed to require that, if DCE is Deduced to below laboratory
detection limits, cleanup must continue until TCA concentrations have been
reduced to 25 ppb.
A.~pff-site Soil Pollution. As aoil pollution has not been detected off-site,
no soil cleanup levels will be established for the off-site areas. Soil
borings may be required to establish that soil pollution above 1 ppm does not
remain after off-site aquifers are cleaned up.
12
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January 5. 1989
STAFF VFOftT ' ' ••&.
5. Croundvater Conservation. Water conservation would be addresi«d in part by
the reinjection of groundvater from all on-aita wells and off^site well RV-
25(B). Additionally, the HPDES permit would be issued on the ejeodition that
Fairchild develop an acceptable plan by January 27, 1989 for reusing extracted
groundvater. This requirement is discussed in more detail later in this
report.
ON-SITE CTJrAMUT* Regional Board staff recommend that the Biode gradation Study
and a modified version of Alt. 4 (In-situ Aeration of the A Aquifer and the AB
Aquitard in Areas with TCA Concentrations Greater than 1 ppm and In-situ Soil
Aeration of the B Aquifer) be implemented for on-site cleanup. This cleanup plan
would entail the following:
1. Croundvater Cleanup Level. Pumping from on-site aquifers would continue
until drinking water action levels (or other drinking water criteria for
chemicals for which action levels have not been established) are achieved for
each chemical unless Fairchild demonstrates that this is technically
infeasible. The current drinking water action levels or other pertinent
criteria are listed in Table 1. At a minimum, pumpit:3 from on-site aquifers
would continue as long as significant levels of chemicals are being removed
via on-site groundvater extraction. Currently, on-site extraction removes
approximately 80 pounds of chemicals per year, compared to approximately 25
pounds per year from off-site extraction.
If drinking water action levels cannot be achieved through in-situ soil
aeration and continued extraction of on-site groundvater, Fairchild will be
required to~ re-evaluate groundvater flushing of the on-site B aquifer to
achieve drinking vater action levels. Staff believe the effectiveness of in-
situ soil aeration in removing chemicals from the devatered portions of the
B aquifer should be established and the results of the biodegradation study
should be evaluated prior to requiring on-site groundvater flushing. When
this information is available, Fairchild will be required to submit a report
evaluating the feasibility of achieving this cleanup level and evaluating
groundvater flushing if drinking water action levels have not been achieved
on-site.
2. Soil Treatment. In-situ soil aeration would be required in dewatered portions
of the B aquifer and in areas of the A aquifer and AB aquitard containing
... greater than 1 ppm TCA. Staff believe this can be accomplished without
installing all of the 61 air extraction wells proposed by Fairchild in Alt.
4. Fairchild has already installed and started operation of an air extraction
well system consisting of 37 extraction wells that effect the A and B aquifers
and the AB aquitard. Regional Board staff recommend this system be operated
for 1 month to initiate soil cleanup and determine the effect of the current
system on soils in the 1 ppm TCA area. At the and of 1 month, Fairchild would
aubmit a report documenting the effect of the current system es £be 1 ppm area
and proposing a final design for the aeration ays tern to clean «m> aoils with
greater than 1 ppm TCA.
3. Soil Cleanup Coal. There is significant uncertainty regarding long-term
operation of in-situ aeration systems; therefore, Regional Board staff have
proposed that a soil cleanup goal be established rather than a soil cleanup
level. A soil cleanup goal of 1 ppm each for TCA, DCE, PCE, Freon-113, and
13 • n
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January 5. 1989
ft?
xylenes is established for on- site soils. A different »ril cleanup '.•*f»l may
be acceptable if Fairchild demonstrates to the satisfaction of the 1 tgional
Board that higher levels of chemicals can remain in n£;-«it« moils Mthout
effecting groundwater concentrations in on- site aquifevs. A, different soil
cleanup level may also be acceptable if Fairchild lemons trates to the
satisfaction of the Regional Board that it is infeaaible to ach5ave the
cleanup goal of 1 ppn and that public health and safety vill be protected.
Mo cleanup goals for acetone and IPX are proposed due to the low rate of
migration of these chemicals from soils into groundvater. their potential for
biodegradation, and the lower toxicity of these chemicals.
6. Integrity of the Slurry Vail . Fairchild' s analysis of the slurry wall has
determined that no loss of fine-grained soils from the slurry wall is expected
to occur if a head differential across the Blurry wall of less than 24 feet
is maintained. Fairchild has estimated tha*' this head differential provides
a factor of safety of 4 with respect to decruxsed effectiveness of the slurry
wall from loss of fines. The current head differential ac;?ss the slurry wall
is 19 feet on the up- gradient side of the slurry wall. * •« part of the final
cleanup plan, Fairchild will be required to ubmit a plan containing measures
that will be implemented to insure the continued integrity of the slurry wall
if drinking water standards are not achieved in on- site aquifers.
7. Biodegradation Study. The Biodegradation Study would also be a component of
on- site cleanup.
8. Deed Restriction. Fairchild would be required to file a deed restriction
prohibiting use of on- site groundwater for drinking water and limiting other
subsurface activities in order to protect and maintain the integrity of the
slurry wall. The deed restriction would remain ih-place until DHS drinking
water action levels are achieved on-site.
HPDES PERMIT
The proposed VDR/NPDES permit establishes effluent requirements for re inject Ion
into the off -site B aquifer, reuse, and direct discharge v,d storm drains leading
to Canoas Creek.
Discharges to storm drains- leading to Canoas Creek mu* t meet best available
technology economically achievable (BAT) effluent requirements. Based on draft
EPA and State Board guidance and past HPDES permits issued by the Regional Board,
air stripping or carbon absorption is usually considered BAT for discharges of
groundvater to surface waters. Air stripping will be required for groundvater
extracted froa on-site wells and from off -site well WJ-25. BAT affluent limits
of 5 ppb for each volatile organic chemical vill be established. These same
limits must also be met prior to reuse of groundwater extracted from these areas .
If the groundvater is reinjected, the discharge must «eet a Hazard Index of 0.25
and be of better or equal quality than existing aquifer conditions. Treatment
belov S ppb for each volatile organic chemical to meet aquifer conditions would
not be required.
Groundvater will also be extracted froa off-site wells RW-2 and RW-22 until a
Hazard Index of 0.25 is established in that part of the plume (Zone 2 in Figure
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;^ '^V _ • January 5, 1989
flAJT UPORT
3.) Considering the low levels of chemicals currently extracted from these wells
(less than 30 ppb in 1988). that extraction is only expected to be required for
up to 2 years, the cost of designing and constructing an acceptable air stripping
treatment systea, and the time required to install the treatment systea
(estiaated to be 11 months), air stripping will not be required for discharge
to Canoas Creek or prior to reuse.
Nozzle aeration has been determined to be a low-cost, easily implemented
mitigation measure that will be required for discharge to the storm drain of
groundvater extracted froa Rtf-2 and RV-22. Nozzle aeration is expected to remove
10 to 50 percent of the volatile chemicals in the discharge.
Until the nozzle mitigation measure can be installed, untreated groundvater from
wells RV-2 and RV-22 will continue to be discharged to storm drains leading to
Canoas Creek. Groundvater extracted from RW-25 and from on-site will continue
to be treated using the existing air stripping system until the nev air stripping ,
system can be put in operation. (The existing system will not meet the effluent;
requirements of the new permit.) It is expected to take up to 9 months for theft
nozzles and the nev air stripper to be operational. •-'
Short term discharges resulting,, from monitoring well sample collection and
aquifer testing in Zone 1 (see Figure 3) shall be treated using air stripping
prior to discharge. Prior to operation of .the nev treatment system, the purge
water from this area will be collected and either treated with the existing
treatment system on site or diluted to meet a Hazard Index of 0.25 prior to
discharge. Monitoring well purge water from all parts of the plume must be
treated or diluted to meet an HI of 0.25 prior to discharge.
Fairchild has objected to the proposed NPDES permit conditions. They consider
the additional costs for air stripping of the groundvater extracted from on-site
wells and from off-site well RW-25 to meet effluent limitations of 5 ppb to be
excessive. Instead, Fairchild has proposed the use of nozzle aertion for this
discharge. Regional Board staff have evaluated costs for air stripping and
determined that it is not excessive for BAT.
Fairchild has also*"objected to moving the compliance point froa Canoas Creek,
es established in the 1982 permit, to a point prior to discharge into the storm
drain. The compliance point was changed primarily to accomplish compliance
monitoring before other storm drain discharges mingle with the Fairchild dis-
charge.
OBJECTIVES OF STAFF'S PROPOSED CLEANUP PLAN ~
The proposed final cleanup plan would meet the following objectives:
Overall protection of human health and the environment
The'proposed final cleanup plan protects human health and the environment by
requiring on-site aquifers to be cleaned up to drinking water action levels and
by requiring off-site aquifers to be cleaned up to a level at least 4 times more
stringent than drinking water action levels. The plan therefore prevents
migration of chemicals above cleanup levels into drinking water supply wells.
Human health is also protected by requiring a deed restriction to prohibit use
15
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anuatj
of on-site groundwater until health standards are achieved. Until cleanup levels.
are achieved in off-«ite aquifer*, vella could potentially be drilled in «*•«*•
of the plune containing chemical concentrations in excess of drinking water
criteria. However, a* part of their permitting process, the SCVWD would advise.•
the potential well owner of the risks associated with such well installation
The proposed plan protects human health and the environment by preventing further
vertical or horizontal migration of chemical concentrations above cleanup levels
in the aquifers.
As required by the HPDCS permit, groundvater containing high concentrations of
chemicals is treated to levels below health standards, water quality standards
and cleanup levels prior to being reused, reinjected, or discharged to surface
waters. Beneficial uses of the receiving bodies, as defined in the San Francisco
Kay Basin Plan, are protected. There will be some discharge of chemicals to the
atmosphere from air stripping, in*situ soil aeration, and volatilization upon
discharge to surface waters; however, concentrations at exposure po'nts will be
below background air levels for these chemicals (primarily TCA). Air emissions
from the air stripper and the in-situ aeration system will also b«. controlled-
by the Bay Area Air Quality Management District (BAAQMD). By at.opping the^
migration of chemicals from soil, and groundvater and treating portions of the|
extracted groundvater and air, potential threats to the environment xe reduced."
Compliance with ARARs
Regional Board staff expect the proposed final cleanup plan will meet all ARARs.
A major requirement for meeting ARARs is achieving MCLs in aquifers that are an
actual or potential source of drinking water. The numerical limits that apply
to chemicals detected in the groundvater are listed in Table 1. This requirement
will be met for off-site aquifers. The proposed order also requires that MCLs
be achieved in on-site aquifers. In order to waive this requirement, Fairchild
must demonstrate to the satisfaction of the Regional Board that it is technically
impractical from an engineering perspective that on-site aquifers be cleaned up
up to drinking water standards. Technical infeasibility, not cost, would be the
major factor considered in waiving this ARAR. To date, Fairchild has not
demonstrated technical infeasibility. If it is determined that drinking water
standards cannot be achieved on-site using information obtained from implement'
tion of the final cleanup plan, the order would have to be modified to waive che
requirement. Even if MCLs are waived as a requirement in a modification to che
proposed order, the final cleanup plan must still be protective of human health
and the environment.
State Board Resolution 68-16 "Statement of Policy with Respect to Maintaining
High Quality of Waters in California," is also an ARAR. This policy requires
that any change in water quality must be consistent with maximum public benefit
and not unreasonably affect beneficial uses. Fairchild estimated the amount of
groundvater that would need to be extracted to achieve an off •site bazaru index
of from 1.0 to 0.0. (Mote that costs required for off-site cleanup should be
roughly proportional to the amount of groundvater extracted.) To reach an HI
of 1.0 could be accomplished in 1 year by extracting 1000 acre-feet of water.
An HI of 0.25 would require an estimated 5 years and 2,200 acre-feet of water.
To reach an HI of 0 (which would require all pollutants to be below laboratory
detection levels) would require the extraction of nearly 9 times more groundvater
16
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, -.,.•••••/<• . . . : January 5, 1989
*4\y$)^4£' •"••'•'tV.^^i^f^;; •'
SXaJF 1IPOKX <"'" ."'"' -;.
«.j
than to reach an HI of 0.25 (18,000 acra-faat compared to£2,200 acre-feet). If
feasible, it would require an estimated 14 years to achieve an HI of 0.
Regional Board ataff believe that the proposed cleanup level of HI-O.25 provides
the best balance of all concerns including cost, technical feasibility, ground-
water conservation, and the requirements of State Board Resolution 68-16 for
maintaining the high quality of the waters of the State.
The proposed cleanup level of aweting drinking water standards on-site is also
consistent with State Board Resolution 68-16 considering the limitations of
technical feasibility and that beneficial uses of the aquifers will be protected.
If new information indicates on-site and/or off-site cleanup levels cannot be
reasonably attained or can be reasonably surpassed, the Board will decide if
further final cleanup actions beyond those completed to attain cleanup levels
shall be Implemented at this site based, to a significant degree, on the informa-
tion developed from implementation of the finei cleanup plan. If changes in
health criteria, administrative requirements, site conditions, or remediation
efficiency occur, Fairchild must submit an evaluation of the effects of these
changes on cleanup levels.
Reduction of toxicicv. mobility, or volume
The proposed final cleanup plan focuses on treatment of the groundvater to
specified cleanup levels. This will reduce the toxicity of the chemicals by
reducing their, .concentrations. Mobility is reduced by use of the groundvater
extraction system, preventing the further spread of the plumes. Also, by
extracting and treating the groundvater. the volume of the plumes will be
reduced. Use of the innovative technology, in-situ soil aeration, also reduces
the toxicity of chemicals by reducing their concentrations. A major factor in
the migration of chemicals through soils to the groundvater is their concentra-
tion; therefore, by reducing chemical concentrations in the soil, their mobility
is also reduced.
Short tern effectiveness
Fairchild's interim cleanup actions largely achieved short term protection. With
the requirement of the on-site deed restriction, the proposed plan is fully
effective in the short term.
~ ".. . ~ ' Leny tern effectiveness and permanence
^The recommended final cleanup plan provides long-term effectiveness and
permanence by removing chemicals from off-site aquifers until an HI of 0.25 is
achieved. Requiring on-site aquifers to be cleaned up to drinking water action
levels and treating on-site soils using in-situ soil aeration also provides long-
term effectiveness and permanence by removing chemicals from on-site coils and
groundvater and by minimizing reliance on the slurry wall. for protecting of f -
site aquifers. . ...
Implementabllitv
17
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January 5, 1989
RAFT MOW i
The off-site plan should be fully implement! ji] within 9 months from adoption of
the Order. The major portions of the on-siU; plan should also be Implemented
within 9 months from adoption of the Order. #•
gost; -
The proposed final cleanup plan is cost effective based on an evaluation of costs
for the entire cleanup, including groundwater and soil remediation, reclamation,
and soil and groundwater treatment.
EPA and other agency acceptance
EPA and DHS staff have been actively involved in the review of the RAP and are
in substantive agreement with the RVQCB staff preferred alternative.
Croundvif.ter conservation -t
The proposed plan requires grouse water conservation to the maxianor extent
feasible. This is discussed in mo e detail below.
Acceptance
The public has had several opportunities to provide input on activities connected
with the Fairchild site.
1. The State Board held a public workshop on February 5, 1988, to discuss
groundvater extraction by IBM and Fairchild. Another State Board workshop
(which was also open to the public) was held in June to discuss a proposed
State Board order requiring reuse of groundwater extracted during the IBM and
Fairchild cleanup operations. This order was adopted at the State Board
meeting on July 21, 1988.
2. In March of this year, the Regional Board at a Public Hearing adopted Order
88*46 requiring Fairchild to submit a water conservation plan. A fact sheet
was circulated to inform the public about the Order and public input was
solicited and considered.
3. DHS released their apidemiological studies concerning the affects on the
community from the consumption of water contaminated by the Fairchild release.
Open forums were held on. May 25 and June 28 to discuss their studies.
A. The Tentative Orders and the BAP were available for public review end comment
from Novmeber 8 through Decem er 8, 1988. Public comment was aL:-o received
at the November 16 Regional Board meeting and at a public meeting held the
evening of November 17, 1988, in San Jose. Additional public comment will
also be accepted at the January 19, 195° Regional Board meeting when the fiz.-.l
orders will be adopted.
Public concerns expressed as a result of these activities have b*en addressed
to the extent feasible in the proposed final cleanup plan. A responsiveness
summary has been prepared addressing comments received.
18
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January 5, 1989
KAFF 1ZFO&T
UKRESOLVED ISSUES
Regional Board staff aspect several areas of the proposed orders and final
cleanup plan Co be conceited. Major issues Include groundvatar rouse, on-site
groundvater cleanup levels, on-sita soil cleanup goals, and operation of the in*
situ soil aeration system. As previously discussed, conditions in the NPDES
perait nay also be contested.
1. Croundvater Reuse. On July 21, 1988, the State Board adopted Resolution 88-
88 which requires that Fair child and IBM develop a plan that results in the
beneficial use of or treatment and recharge of a significant amount of their
extracted groundvater. If use or recharge of significant aaounts is not
proposed. Fairchild (and IBM) shall fully justify reasons for not using or
recharging the groundvater. The justification mist also demonstrate why
continued pumping is necessary from the standpoints of public health,
protection of potential and present beneficial uses, maintaining high quality
water, and providing the maximum benefit to the people of the State.
The staff's recommended cleanup plan was developed considering groundvater
conservation and the requirements of the State Board's Resolution. A aajor
factor effecting Fairchild's ability to reuse the extracted groundvater is
the length of time that extraction will continue. In order to conserve water,
groundvater extraction wells will be shut dovn sequentially as cleanup levels
are achieved in different portions of the aquifer. Extraction froa two off-
site wells (RW-19 and RW-27) with concentrations currently below an HI of 0.25
will be terminated as soon as the final Order is adopted, decreasing
Fairchild '"s extraction by up to 500 gpm.
Fairchild will be required to reuse or reinject all of the water that will
be extracted from on-site and from off-site well RV-25 (resulting in the
recharge of 480 acre-feet of water). This should result in 100 percent
conservation for the last three years required for cleanup.
Assuming an off-site cleanup level of HI-0.25, two of the other three off-
site extraction wells should be shut down after two more years of pumping.
Groundvater reuse or reinjeetion froa these two wells is limited due to the
9 to 16 months that would be required to construct any necessary treatment
and/or distribution systems, obtain permits, otc.
The proposed SCR requires Fairchild to develop a groundvater conservation
plan. This plan must contain the partial reinjeetion measure described-above
plus additional measures for reuse of extracted groundvater. The proposed
order establishes a goal of 100 percent reuse; hovever, considering the short
term nature (2 years) of the bulk of Fairchild'> off-site extraction and that
•ost potential users need water only on an intermittent basis, Fairchild's
ability to implement a program for reusing a significant portion of their
extracted groundvater will be limited.
Another issue effecting groundvater reuse concerns EPA's interpretation of
the Resource Conservation and Recovery Act (RCRA). The tank that failed
released a RCRA hazardous waste into the subsurface. It is EPA's position
that the polluted groundvater resulting from this release contains a RCRA
hazardous waste, and, consequently, the groundvater must be disposed of in
19
-------
January 5, 1989
STAJT EXPORT
accordance with RCRA regulations. If the groundwater is discharged to surface ^
waters (e.g., Canoas Creek) under an HPDES permit, it is exempt from RCRA. s||
However, if the groundwater is not discharged to the creek, it may have to |.
be disposed of or reused, if possible, in accordance with RCRA. This could ;^
prohibit using the extracted groundwater for irrigation, construction, or i|
other purposes, even though the groundwater meets drinking water standards. |
Fairchild has contacted two potential users that appear interested in reusing
the groundwater. One potential user, Live Oaks Farm, is currently using 600
gpm on an intermittent basis. This use of the water may have to be curtailed
pending resolution of this issue. The other interested party is CalTrans.
CalTrans may be able to use up to 50 gpm. Fairchild has indicated reuse by
Caltrans is dependent on resolution of the RCRA issue.
Fairchild is expected to contest the part of the order requiring partial
reinjection. Other parties have commented on this and other issues associated
with groundwater conservation. ;
2. On-site Groundvater Cleanup Levels. Fairchild has objected to the proposed
cleanup requirement of meeting drinking water standards on-site. F*irchil«.
maintains that drinking water standards should not apply to the small amour
of groundwater within the slurry wall and that this groundwater is teydrauli-
cally disconnected from other aquifers. Additional information concerning
this issue is available in the responsiveness summary.
Other parties have commented on the potential effect of the proposed cleanup
plan on dovngradient drinking water supply wells. As previously discussed,
the concentrations expected to reach these wells are well below the drinking
water action level of 200 ppb for TCA. The Regional Board also considered
potential migration of chemicals into GO-4 when Order 88-46 was adopted. This
Order allows up to 5 ppb TCA to migrate into compliance wells located within
approximately 400 feet of GO-4.
Unresolved issues associated with on-site soil goals and operation of the
aeration system are connected to the differences between Fairchild's proposed
plan and the final cleanup plan proposed by Regional Board staff.
KOLL COMPANY DEVELOPMENT
The Koll Company has proposed developing a shopping center on the property. Any
development must not interfere with soil and groundwater cleanup and monitoring
activities. Regional Board staff have met with Koll to discuss these conditions
and to advise Koll that, as a property owner, they may be held liable for pist
and/or future discharges of pollutants. Fairchild is working with Koll to ins ore
that cleanup activities and shopping center construction are eorpatible.
PUBLIC INVOLVEMENT
Community involvement has been actively encouraged by the Regional Board. All
Regional Board and State Board orders which called for, modified, or effected
the cleanup plans have been adopted at public hearings (Regional Board in August
1986. March 1987, and March 1988; State Board in February and June 1988).
Additionally, DHS released their epidemiological studies concerning the effects
20
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_ January 5, 1989
STAFF UPQRT
on the community froa the consumption of mt«r contaminated by the Fairchild
release. Open foxvas were held on May 25 fitid June 28 to discuss these studies.
Public input vas requested for all of these activities and has been incorporated
into the proposed orders to the extent feasible.
In preparation for adoption of the final Remedial Action Plan, the Regional Board
has also taken or vill take the following actions to involve the public in
determining acceptable alternatives and in the final decision-making:
1. Staff sent out three fact sheets discussing the RAP and the proposed final
cleanup plan. Persons receiving these fact sheets included adjacent
neighbors, local government officials both appointed and elected, the water
utilities using the groundvater, and those interested individuals that
responded to several newspaper advertisements announcing the RAP process and
decision-aaking.
2. The tentative orders for final cleanup have been circulated to concerned
agencies, governaent off icials,, and citizens groups.
'• . ^
3. Prior(to official release of the proposed final cleanup plan. Regional Board
staff'off erred to discuss the proposed plan with local officials and concerned
environmental groups.
4. Initial testimony was received at the November 16, 1988, Regional Board
meeting.
5. The Regional Board staff held an evening public workshop on November 17, 1988,
in the vicinity of the Fairchild site.
6. The Administrative Record has been available to the public since the announce-
ment of- the tentative cleanup plan. The draft and revised versions of the
cleanup plan have been available to the public in the Santa Teresa Public
Library in the vicinity of Fairchild since September 1987 and in other
libraries since the announcement of the tentative cleanup plan. Additionally,
all reports (including all drafts of the RAP), correspondence, and other
submittals contained in Regional Board files, are available to the public
during normal business hours and have been available as submitted since the
initial discovery and Regional Board actions.
7. Comments were be accepted on the RAP and the proposed orders from November
8 until- December 8, 1988. A responsiveness summary was prepared and
circulated to parties expressing significant concerns.
8. The Final Remedial Action Plan vill be adopted by the Regional Board in a
public "hearing where final comments on the Plan aay be offered by the
interested public.
ADVERSE IMPACTS RESULTING FROM IMPLEMENTATION OF THE PROPOSED FINAL CLEANUP PLAN
Implementation of the proposed final cleanup plan will impact the public and
environment as described below.
21
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January 5, 1989
One iapact will be to residential |£»ads an£ property. Pipes and nozzles will
need to be installed in and adjaeemvto Via d*l Oro between Great Oaks Boulevard
and San Ignacio Avenue (near extract^ an welttM-2). Additional awnitoring wells
and/or piezometers will be instal' «d on private property oece property owners
grant access. This proposed off-s|:.ie construction aay interfere with traffic
flow and residents in the area. This interference would laet for the construc-
tion tiae necessary for each treataent unit and pipe to be installed, which
should be a •••» <•»«•» of a few aonths. This iapact is not considered to be
signifeant. ,
A second iapact will be redistribution of chemicals froa the groundvater to the
air, surface waters, and possibly landfills. The proposed nozzle treataent and
air stripping treataent without activated carbon air treataent would transfer
dilute concentrations of cheai<*als froa the groundwater to the air. Spent
activated carbon used with the in-situ soil aeration systea and, if required by
the Bay Area Air Quality (tanageacnt District, with the air stripping systea would
be distributed to eithe. landfills or to incinerators for chemical breakdown.
Concentrations of chemis-ils below laboratory detection liaits froa Guadalupe
River aay recharge aquix trs and aay flow into the southern portion of the San
Francisco Bay. These Affects will not have a significant iapact on public
health.
A third iapact would be that low cheaical concentrations will reaain in the
aquifer and affect water supply wells. Cheaical concentrations in down-gradient
water supply well GO-4 are expected to reach up to 5 ppb TCA. The minimal
increases allowed should not iapact beneficial uses and will still be protective
of human health. Cheaical concentrations are not expected to be detected in
other drinking water supply wells. Regional Board staff do not consider these
effects to be significant.
RECOMMENDATION
1. The draft RAF as described in this report and aaended by the addendum attached
to this report and the Tentative Orders should be found generally acceptable
based on the Health and Safety Code Sec~ijn 25356.1.
2. The draft RAF as aaended by toe adflindua attached to this report and the
Tentative Orders should be considered to aeet Section 121 of CERCLA as an
equivalent to a feasibility study and found to be protective of human health
and the environment, attain ARARs, be cost affective, utilize permanent
solutions and alternative treataent technologies and resource recovery
technologies to the aaxiau^ extent possible, reduce toxicity, mobility, and
volume of pollutam «, and address the concerns of the public.
22
-------
ItAJF.lZPORT
January 5, 1989
Concur:
Concur:
:
Vil Bruhns, "Section Leader XcVStcve Morse, Division Chief '4-
Attachaentc: AGENCY ADDENDUM DATED DECEMBER 16. 1988
Figure 1 - SITE LOCATION
Figure 2- B AQUIFER TCA CONCENTRATIONS
Figure 3 - GROUNDUATER REMEDIATION ZONES
Figure A - OFF- SITE IMPLEMENTATION SCHEDULE
Table 1 - CHEMICAL CONCENTRATIONS IN AND DRINKING WATER CRITERIA FOR ON -SITE
CROUNDVATER
Table 2 - OFF- SITE CHEMICAL CONCENTRATIONS AND DRINKING WATER STANDARDS
Table 3 - MAXIMUM SOIL CHEMICAL CONCENTRATIONS ' •
Table A - OFF- SITE COSTS •£ _h
Table 5 - ON- SITE COSTS :
Table 6 - OFF- SITE CLEANUP TIMES
23
-------
!i
Figure 1
Site Location
-------
-------
January 5. 1989
RATF BIPOftT
TABLE 4
COST SUMMARY FOR OFF-SITE CLEANUP ALTERNATIVES
Alt HI Capital Costs
1
2
2
3
3
4
4
5
5
6
6
7
7
...
1.0
0.25
1.0
0.25
1.0
0.25
1.0
0.25
1.0
0.25
1.0
0.25
$ 227.500
227,500
227,500
2,802,200*
2.802,200*
1,981,400
1,981,400
1,200,200
1,200,200
1,602,400*
1,602,400*
" " 457 , 200
457 . 200
Total
06M Costs
$ 745,400
2.329.800
4.124.800
3,057,800*
6 , 394 , 100*
2,512,900
5.191.800
2.596,400
5,292,700
2,916.200*
5,694,000*
2,367,800
4,314,800
Total Cost
$ 972,900
2,557.300
4.352.300
5,860.000*
9.196,300*
4.494,300
7,173,200
3,796,600
6.492,900
4,518,600*
7,296,400*
2,825,000
4,772,000
Present
Worth Costs
$ 690.400
1.825.400
3.037,300
5.027.100*
7.227,600*
3.745.7QO
5,589,000
3,040,400
4 , 907 , 500
3,705,100*
5,535,800*
2,089,600
3.411,000
* assumes pipeline easeaents can be negotiated (land would not have to be
purchased)
TABLE 5
COST SUMMARY FOR ON-SITE CLEANUP ALTERNATIVES
Alt *
1
2
3
4
5
6'
Capital Costs
$ o
318,800
2.202.800
3,532,500
2,941,300
4,198.100
Total
O&M Costs
$ 332.500
4,877,000
2,436,500
2.916,900
6,207,300
11,237,600
- Total Cost
$ 332 ,500
5,195,800
4,639,300
6.449,400
9.148,600
15.435,700
Present
Worth Costs
$ 155.600
1,940,700
4,221,000
5,982 100
7.642.300
11,868,900
-------
Pigur« 3
GROONDHATBR REKE01ATIOII ZONKS
-------
%^
f
ll
ll
TASK
M.TBNMTIVI
ATNM tCMRNNJI
ALTERNATIVE No. I
HO FURTHER ACtlQM
ALTERNATIVE Ma. 1
DISCHARGE TO CANQAS CREty
ALTERNATIVE No. 3
PiPUJNf. TO COYOTE CRta
INSTALLATION OT PIPE •«
MSTALLATION OF MR STRPPMG TOWER •••
ALTERNATIVE Ma. 4
EXTRACTION. TREATMtN,T AMD REIN^CTTQH
INSTALLATION OF PIPE ••
INSTALLATION OF MR STRIPPING TOWER M*
ALTERNATIVE Mo. 5
TREAT AND DISCHARGE TO CANOAS CRttK
MSTALLATION OF PIPE ••
MSTALLATION OF MR STRIPPING TOWER •*•
ALTEKHMTVE Ma. 8
PIPtJJNi: TO COLT COURg
MSTALLATION OF PIPE »•
ALTERNATIVE No. 7
INSTALLATION OF MR»HMO
ALTERNATIVCS 2 TMROUCH 7
YEAR 1
t« MONTHS
a MONTHS
14 MONTHS
t MONTHS
CASE 1: Ml » 1.0
CASE J: Ml - O.JS
m
YEAR 2
YEAR 3
w//////////m
YEAR 4
YEAR 5
T':y*
MIOEfc.
IMPLEMENTATION OP THE ALTERNATIVE CAN BEOM
»• MSTALLATION WCLUOES DESIGN OF PIPING SYSTEM. LA»O ACQUISITION (PERMITS. PURCHASING
OT EASEMENT). THENCMING. PIPE INSTALLATION AND JACKING UNDER ROADWAYS. RAILROADS.
AMD HIGHWAYS, AS APPLICABLE.
* INSTALLATION .INCLUDES DESIGN. ACQUISITION Of PERMITS. AK CONST
.«•« MVIAULATKM DOCS MOT RCOMIRt TIME TO NEGOTIATE rOR LAND USE.
TM OF TOWER.
REMEDIATION ALTERNATIVE MPUEMEMTATKM
TIME SCHEDULE
Figure 4
-------
January 5. 1989
RAFF.U70RT
TABLE 1
CHEMICAL CONCENTRATIONS IN ON-SITE CROUNDUATER
1982 Maxima
Chemical Concentration (pob)
1987 Maxlama
Concentration (potO
DHS Drinking Water
Aerion Level1
TCA
Xylenes
Acetone
IPA
Freon-113
DCE
PCE
1,900.000
76,000,000
99,000,000
45,000,000
46.000
53,000
2,700
100.000
16,000
88,000
5,700
12
14,000
330
200
6202
(3.500)3
(450)'
18,000
6
2*
1 Except as noted, on-site groundvater cleanup levels are listed at DHS drinking
water action levels as of the adoption of the Order. If DHS drinking water
action levels change, on-site groundvater cleanup levels will change accordingly.
If the MCL for any chemical becomes aore stringent than the DHS drinking water
action'level, then the MCL shall be the cleanup level for that cheaical.
2 Value is fpr a single isomer or sun of the three.
'v^'"
a MCLs and DHS Drinking Vater Action Levels have not been established these
chemicals. The value for acetone is established based on the oral reference dose
(Rfd) in the Integrated Risk Management Information System (IRIS). The value
for IFA is based on the DHS -Site Specific Remediation Criterion for IPA.
* The value for PCE is the proposed State MCL. If the final MCL is not the
proopsed value of 2 ppb, the final cleanup goal shall be modified accordingly.
-------
January 5, 1989
RAFF 1ZPOB.T
TABLE 2
OFF-SITE CHEMICAL CONCENTRATIONS AND DRINKING WATER STANDARDS
Chemical
TCA
DCE
1982 Maximum
Concentration
7.500 ppb
38 ppb
Currant Maximum
Concentration1
430 ppb
31 ppb
DHS Drinking Vater
Aetipn Level*
200 ppb
6 ppb
1 Well 128(B) data collected 9-12-88
2 Current DHS drinking water action levels are at least as stringent as current
Maximum Contaminant Levels (HCLs).
TABLE 3
MAXIMUM SOIL CHEMICAL CONCENTRATIONS
Chemical
TCA
Xylenes
Acetone
1PA
Freon-113
DCE
PCE
1982 Mflxirn**^
Concentration
Concentration Boring
(*BWJ i w
7,900
5,600
12; 000 ,
30.000
0.27
160
160
Caisson 149
Caisson 31
- Caisson-67 .
Caisson 67
B-103
B-113
B-101
1988 Maxim"™. Concentration
Depth
(ftl
34.0
32.0
38.0
38.0
38.0
31
31
Concentration
8.200
3,700
1,300
1.4001
0.12
63
10
Boring
SB-240
SB-241
SB-263
SB- 205
SB-249
SB-240
SB-242
Depth
• 4
63
40
40
52
51
64
This concentration was detected in 1987, not 1988.
-------
HI-0.25
January 5, 1989
flaTF UNIT
''•>_
6 - OFF-SITE CLEANUP TIKES
Off-.!« . M-«« ««», TU.
100°
-------
December 16, 1988
TO TO nun IBFO&T
AGENCY ADDENDUM FOR
REMEDIAL ACTION PLAN - FAIRCHILD SEMICONDUCTOR CORPORATION
On October 7, 1988, Fairchild submitted a revised Remedial Action
Plan (RAP) describing interim remedial activities, evaluating final
cleanup levels and alternatives, and proposing a recommended final
cleanup plan for their San Jose site. Regional Board staff have
determined that the technical information contained in the RAP is
acceptable for developing a final cleanup plan; however, Regional
Board and other agency staff do not accept all interpretations and
recommendations contained in the RAP. The RAP submitted October
1988 as modified by this Addendum, the staff report, the Site
Cleanup Requirements for the site, and the NPDES permit satisfy the
requirements of the Health and Safety Code for a final remedial
action plan and the NCP requirements for a remedial investigation
and feasibility study.
I. NPDES PERMIT. Fairchild obtained an NPDES permit in 1982 for
the discharge of polluted groundvater to surface water. Prior
to its expiration, Fairchild applied for a renewed NPDES
permit from the Regional "Board. Fairchild will receive a
renewed NPDES permit as part of their final cleanup plan.
Fairchild1 s discharge can be divided into flows from two areas
as shown in the attached figure: (1) groundwater extracted
from Zone 3 (which includes off-site well RH-25 and pumping
fi'om within the slurry vail), and (2) groundwater extracted
from Zone 2 (which includes off-site veils RW-22 and RW-2).
If the final cleanup plan is adopted as proposed, there will
be no extraction from Zone 1. Groundwater containing high
chemical concentrations vill be extracted from Zone 3 at a
rate of up to 100 gpm. Groundvater extracted from Zone 2, up
to 1100 gpm, vill contain a maximum of 50 ppb TCA.
Fairchild maintains that the nev NPDES permit should contain
conditions essentially the same as those established in their
1982 permit (see RAP pgs 75-78, 114-116, and 174-175).
Fairchild's proposal vould allow all extracted groundwater to
be discharged to Canoas Creek after nozzle treatment at permit
limits of up to 5 ppm TCA.
NPDES permit conditions for the disposal of polluted ground-
vater must be established using Best Available Treatment
Economically Achievable (BAT) based on Best Professional
Judgment (BPJ).. Regional Board staff maintain that Fair-
child's proposal does not meet BAT/BPJ requirements. Staff's
proposed BAT/BPJ permit requirements and monitoring require-
ments for the Fairchild-San Jose site are as follows:
A. Effluent Limitations. BAT/BPJ effluent limitations for
the water extracted Zrom Zone 3 vould require air
stripping to 5 ppb for most volatile organic compounds.
-------
—December 16, 1988
AGENCY ADDENDUM
Groundvater extracted from Zone 2 will only be extracted
for an estimated 2 years. It would talc* approximately
one year to obtain the necessary permits and easements,
and design and construct an off-site treatment system at
a cost of approximately $2 million. Requiring air
stripping treatment for this discharge would cost about
$10,000 per pound of chemicals removed. The groundvater
currently contains chemical concentrations well below
drinking water standards and water quality criteria.
Therefore, Regional Board staff propose allowing
groundvater extracted from Zone 2 to be discharged after
nozzle treatment to Canoas Creek. Effluent limitations
will be proposed at current groundwater concentrations.
B. Nozzle Treatment. Pairchild has proposed that nozzle
treatment is BAT/BPJ for the polluted groundwater. The
nozzle system proposed by Fairchild would have an,
estimated removal efficiency of 10 to 50 percent. The
flow would be discharged through nozzles directly into
the storm drain, making monitoring after treatment
dificult or impossible. Due to the uncertainties in
treatment efficiency and the difficulty monitoring
directly after the nozzles, Pairchild proposes that no
treatment efficiency be required.
Regional Board staff maintain that these limitations
preclude the designation of nozzle treatment as BAT/BPJ
and that the system proposed by Pairchild is not a fully
developed treatment system. As there may be some benefit
to aerating the groundwater through nozzles prior to
discharge, Regional Board staff have included the use of
nozzles as a mitigation measure to allow an exemption to
Basin Plan prohibitions and to decrease chemical
concentrations entering surface waters.
C. Compliance Point. Pairchild has proposed that the
monitoring point for determining compliance with permit
restrictions be reestablished at the same point as in
their 1982 permit. This location is approximately 20
feet downstream from where the storm drain containing
Pairchild's groundwater discharges to Canoas CreeV.
Regional Board staff strongly object to this complianue
point because: (1) Pairchild'• discharge may mingle with
other flows in the storm drain prior to discharging to
Canoas Creek, (2) the compliance point should be
established at a point where Pairchild maintains control
of the discharge, and (3) it is very difficult to collect
an unaerated sample at this point, causing the concentra-
tion of volatile compounds to be reduced when a sample
is collected.
-------
—December 16, 1988
J • ••,-) ,<; .'
' " 1 1
AGENCY ADDENDUM
Regional Board staff propose the compliance point be
established after the air stripping system for ground-
water extracted from Zone 3 and prior to Discharge into
the storm drain for groundvater extracted/ froa Zone 2.
II. APPLICANT -^ Qp RTiTJ^ANT AND APPROPRIATE REQUIREMENTS. Cleanup
at a Superfund site Bust comply with legally applicable or
relevant and appropriate requirements (ARARs) . Regional
Board, EPA, and DBS staff disagree with several of Fairchild's
conclusions regarding ARARs. ARARs for the site consist of
the ARARs identified in pages 102-118 of Fairchild's RAP with
the following modifications.
A. On-site Groundwater as a Potential Source of Drinking
yater. Maximum Contaminant Levels (MCLs) established
under the federal Safe Drinking Water Act (SDWA) must be
achieved for potential sources of;>drinking water. Under
State Board Resolution 88-63, a "Adoption of Policy
Entitled 'Sources of Drinking Water,1" groundwater
contained within the boundaries of the slurry wall (on-
site) meets the definition of drinking water and is
therefore a potential source of drinking water. EPA's
"Guidelines for Groundwater Classification under the EPA
Groundwater Protection Strategy," Final Draft, December
1986, also establishes on-site groundwaters as a
potential source of drinking water. Therefore, unless
the requirements for waiving an ARAR are met (e.g.,
achieving MCL's is technically impracticable from an
engineering perspective) , MCLs must be achieved in on-
site groundwaters.
Fairchild maintains that MCLs should not be established
as the on-site cleanup level because: (1) State Board
Resolution 88-63 is not an ARAR, and (2) the on-site
groundwater is hydraulically disconnected, from the
aquifer system by the slurry wall.
Regional Board staff maintain that State Board Resolution
88-63 is an ARAR and MCLs are required on-site.
Furthermore, staff questions whether slurry walls have
been proven to provide permanent containment. Staff are
also very concerned with the precedent established by
allowing a slurry wall to determine that an aquifer that
was previously a potential source of drinking water is
no longer a potential source of drinking water. By
proposing the slurry wall as a permanent cleanup solution
and leaving chemical concentration above drinking water
standards on-site, Fairchild is in effect creating a 22
acre hazardous waste disposal area.
B. SWRCB Resolution 68-16. The RAP states that State Board
Resolution 68-16, "Statement of Policy with Respect to
-------
December 16, 1988
AGENCY ADDENXXnt ,j$r
Maintaining High Quality of Wats.f* in California" may not
be an ARAR since "it is not clea; whether th« policy has
been * promulgated." Regional ;r>oard position is that
State Board Resolutions 'are l«*|lly enforceable ARARs.
C. SWRCS Resolution 68-1$ and Water Code Sections 100 and
22£. California Water Code Sections 100 and 275 prohibit
the unreasonable use of water. Fairchild maintains that
these Water Code sections and Resolution 68-16 are in
conflict because restoring the aquifers to background
conditions vould require the pumping of large quantities
of water. Staff's positions is that the requirements of
Resolution 68-16 and Water Code Sections 100 and 275
could both be fulfilled if the extracted groundvater vas
reused or reinjected.
si
D. Subchaotcr 15. Fairrfiild maintains that Title 23,
Chapter 3, Subchapter 15 is not an ARAR for the site.
Staff maintains that, if wastes are left on-site that
need to be contained <&« in Fairchild's proposed plan),
the cleanup is subject to Subchapter 15 unless "remedial
actions intended to contain such wastes at the place of
release shall implement applicable provisions of this
subchapter to the extent feasible" (Section 2511).
E. SCRA. Pollution at the Fairchild-San Jose site was
caused by the failure of a tank containing a hazardous
waste regulated by the Resource Conservation and Recovery
Act (RCRA). Contrary to Fairchild's interpretation
presented in the RAP, current EPA policy is that ground-
water contaminated with a hazardous waste is subject to
regulation by RCRA.
F. Reinfection. Under EPA's current interpretation of
groundvater polluted by a RCRA hazardous waste, reinjec-
tion of extracted groundwater *;xild be subject to the
re injection requirements of tb« Safe Drinking Water Act
(SDWA). According to discussions with EPA staff, these
requirements for Superfund activities are limited to
reporting requirements.
-------
3
j
\
o .tf
GROUNDIMTBII REHBDIATIOH BOW
-------
PART 3
-------
CALIFORNIA REGIONAL. WATER QUALITY CONTROL BOARD /te
SAN FRANCISCO BAY REGION **'.
ORDER NO. 89-16
SITE CLEANUP REQUIREMENTS FOR:
FAIRCHILD SEMICONDUCTOR CORPORATION AND SCHLOMBERCER TECHNOLOGY CORPORATION
SAN JOSE
SANTA CLARA COUNTY
The California Regional Water Quality Control Board, San Francisco Bay Region
(hereinafter called the Regional Board), finds that:
1. Site Location. Fairchild Semiconductor Corporation and Schlumberger
Technology Corporation, hereinafter called the dischargers, owned : and
operated a semiconductor manufacturing facility at 101 Bernal Road in^the
City of San Jose. The dischargers operated the facility from April .^977
until the facility was closed in October 1983. The facility has been
inactive since 1983.
2. Property Transfer. In 1987, all issued and outstanding shares of Fairchild
stock were sold by Schlumberger Technology Corporation ("Schlumberger")
to National Semiconductor Corporation. Following the sale, Schlumberger
retained the site of Fairchild's former San Jose Facility. However,
Fairchild retained all environmental liabilities associated with its past
activities at the site. Schlumberger is currently managing the cleanup
on behalf of Fairchild. Schlumberger has entered into a contract to sell
the 22 acre site to the Roll Company. Koll plans to develop the property
as a neighborhood, shopping center.
3. Regional Board Orders. The Regional Board adopted Waste Discharge Require-
ments in Order No. 86-62 on August 20, 1986 for the dischargers' interim
site cleanup. Order No. 87-16, adopted March 18, 1987, rescinded Order
No. 86-62 and prescribed site cleanup requirements for the dischargers'
interim cleanup. Order No. 87-16 was amended on March 16, 1988 by Regional
Board Order No. 88-46. Orders 88-46 and 87-16 are rescinded by this Order.
This Order sets tasks and submittal dates for final site remediation -to
be consistent with the Health and Safety Code and the National Contingency
Plan. "....,„ .-
4. Lead Agency Designation. The dischargers' San Jose site is proposed for,
inclusion on the National Priorities- List (NPL) under the Comprehensive
Environmental Response, Compensation, and Liability Act of 1980 (CERCLA).
The site is also included on the California Expenditure Plan for the
Hazardous Waste Cleanup Bond Act of 1984. Pursuant to the South Bay Multi-
Site Cooperative Agreement and the South Bay Ground Water Contamination
Enforcement Agreement, entered into on May 2, 1985 (as-subsequently
amended) by the Regional Board, the Environmental Protection Agency (EPA),
and the Department of Health Services (DHS), the Regional Board has been
acting as the lead agency overseeing cleanup of the site. The Regional
Board will continue to regulate the dischargers' remediation and enforce
-------
SITE CLEANUP REQUIREMENTS - FAIRCHILD-SAN JOSZ FINAL CLEANUP
under CERCLA as amended by Che Superfund Amendment and Reauchorizatioti Act
of 1986 (SARA). r,
5. Potential Responsible Parties. Pursuant to Health and Safety Code
25356. l(d) and 25356. l(c), the dischargers are the only identified or>known
responsible parties associated with the release of pollutants to the; sub-
surface .
6. Pollutants Detected. In November 1981, the dischargers discovered that
an underground organic solvent tank had failed, releasing a mixture of
solvents including 1,1,1-trichloroethane (TCA) , 1,1-dichloroethene (DCE) .
tetrachloroethene (PCE) , isopropyl alcohol (IPA) , xylenes, acetone, and
l,l,2-triehloro-l,2,2-trifluoroethane (Freon-113) to the subsurface. All
of these chemicals have been detected in soils and groundwater within the
dischargers' property boundaries. TCA, DCE, and Freon-113 have also been
detected off -site. TCA is the pollutant that has been detected most
frequently and in the highest concentrations.
7. Hydroeeologv. Three aquifers, designated the A, B, and Cj aquifers, have
been polluted by the release. The A aquifer varies frots- 10 to 40 feet
thick and is first encountered at depths of 10 to 20 feet below the ground
surface. The A aquifer is not continuous off -site (outside Faircbild's
property boundaries) and is currently generally dewatered. . The B aquifer
is generally located between depths of 60 and 120 feel: below ground
surface. The C aquifer is generally found between 150 and 190 feet below
ground surface. Only trace levels of pollutants have ever been detected
below the B aquifer on-site or below the C aquifer off -site.
8. Interim Actions. The dischargers have been extracting groundwater from
the Santa Teresa Basin as part of its interim cleanup program since January
1982. Other interim actions taken by the dischargers include removing the
defective tank, excavating 3,389 cubic yards of soil, installing a slurry
wall around the perimeter of the property, sealing potential conduits, and
conducting pilot studies for on-site aquifer flushing and in- situ soil
vapor extraction.
The dischargers' interim actions have brought the plume under hydraulic
control, significantly reduced the size of the plume, and significantly
reduced solvent concentrations within the plume . The length of the pluEfv
has been reduced from a maximum of 4,900 feet in October 1982 to approxi-
mately 2400 feet. The maximum concentration of TCA detected off -site has
been reduced to 430 ppb (9-12-88 data) from 5600 ppb in November 1982.
TCA concentrations in the C aquifer are below 5 ppb .
9. NPDES Discharge . The extracted groundwater has been discharged under an
NPDES Permit, Regional Board Order No. 82-61, with and without treatment
'to storm -drains leading to Canoas Creek. Canoas Creek is tributary to the
Guadalupe River which flows into south San Francisco Bay. The Regional
Board will reissue a NPDES permit as part of this cleanup plan. Un'dsr the
. new permit, volatile organic chemical concentrations of up to 100 ppb each
chemical may enter Canoas Creek during the next two years. At the end of
two years , discharge of most volatile organic chemicals to Canoas Creek
must not exceed 5 ppb for each chemical.
Recharge from Canoas Creek may occur to a slight degree. The Guadalupe
River provides significant recharge to shallow groundwater aquifers along
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SITE CLEANUP REQUIREMENTS -, FAIRCHILD-SAN JOSE FINAL CLEANUP
dts length. No additional investigation of Canoas Creek recharge is
planned due to the very low concentrations of chemicals currently being
discharged into the creek by thegdischargers and the insignificance of
recharge in Canoas Creek. :|',|
j > V-
10. The Slurry Vail. In 1986. the dischargers installed a 3-foot thick slurry
wall around the perimeter of theirvproperty. The slurry wall is keyed into
tbo BC aquitard and encloses approximately 22 acres. If a head differen-
tial across the slurry wall of less than 24 feet is maintained, no loss
of fine-grained soils from the slurry wall is expected to occur. The
dischargers have determined that this head differential provides a factor
of safety of 4 with respect to decreased effectiveness of the slurry wall
from loss of fines. The current head differential across the slurry wall
is 19 feet on the up-gradient side of the slurry wall and less than 2 feet
on the down-gradient side.
11. Groundvater Overdraft. As a result of aquifer cleanup, low rainfall,
reduced active recharge efficiency, and increased groundwater extraction
for water supply purpose^, groundwater elevations have declined throughout
the Santa Teresa Basintsince 1981. In March 1988, the Regional Board
adopted Order No. 88-45.' requiring the dischargers to develop a water
conservation program for the C aquifer. As a result of the water
conservation program and the effectiveness of interim cleanup, the
dischargers terminated .groundwater extraction from the C aquifer on
September 6, 1988.
12. Draft Remedial Action Plan. The dischargers have submitted a remedial
action plan as required by Regional Board Order 87-16. The technical
information contained in the remedial action plan (RAP) is consistent with
the Health and Safety Code requirements for a final remedial action plan
and the National Contingency Plan (NCP) requirements for a remedial
investigation and feasibility study (RI/FS). The RAP contains an
evaluation of interim cleanup actions, an evaluation of groundwater conser-
vation measures, an evaluation of final cleanup alternatives, proposed
cleanup levels, a recommended final cleanup plan, and a public health
evaluation.
DHS and EPA have reviewed and commented on the draft RAP submitted by the
LT^.dischargers. The initial draft RAP has been available for public review
, -.since September 1, 1987.
•*i
Regional Board staff have determined that the technical information
contained in the revised RAP submitted October 7, 1988, is acceptable for
developing a final cleanup plan for the site. In making this determina-
tion, staff did not accept the portions of the RAF addressing: (1)
Applicable^or Relevant and-Appropriate Requirements (ARARs), and (2) the
NPDES permit. These areas'are addressed in the Addendum to the RAP dated
December 16, 1988, prepared by agency staff. The RAP submitted October
,7^5,4988 as modified by the Addendum, the -staff report, this Order, and
Order No. 89-15 (NPDES Permit No. CA 0028185) satisfy the requirements of
the Health and Safety Code for a final remedial action plan and the NCP
requirements for a remedial investigation and feasibility study.
13. Cleanup Alternatives. In the RAP, the dischargers evaluated cleanup levels
and alternatives separately for the on-site and off-site areas. The
dischargers evaluated seven alternatives for off-site cleanup and six
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SITE CLEANUP REQUIREMENTS - FAIRCHILD-SAN JOSE FINAL CLEANUP
alternatives for on-s.'te cleanup. A complete description of these alterna-
;••' tives is contained in fche RAP dated October 7, 1988. The alternatives were
• evaluated based on tenicriteria: (1) overall protection of human health
'- and the environment; v2) compliance with all federal and state applicable
or relevant and appicpriate requirements (ARARs); (3) reduction of
• toxicity, mobility or irjlume; (4) short term effectiveness; (5) long term
! effectiveness; (6) Uplementability; (7) cost; (8) State and EPA
acceptance; (9) ground ater conservation; and (10) community acceptance.
14. Hazard Indices. The dischargers evaluated off-site groundwater cleanup
levels using Hazard Indices (His). The HI is a method for assessing the
public health risk associated with exposure to multiple chemicals. A HI
equal to 1 indicates that all chemicals of interest are present at or below
their relevant drinking water criteria. Hazard Indices are usually calcu-
lated separately for carcinogenic and non-carcinogenic chemicals. For the
Fairchild site, Hazard Indices were only calculated for non-carcinogenic
chemicals because there are no known potential carcinogenic chemicals in
off-site gro mdwaters and only one potential carcinogen, PCE, has been
detected on:site. PCE is present in on-site groundwater at a concentration
of up to 85 ipb, which is equivalent to a carcinogenic Hazard Index of
21.3. DHS an
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SITE CLEANUP REQUIREMENTS - iPARCHILb^iSANi'JOSE FINAL CLEANUP
•r
ppm and that public health and the environment will be protected.
Information obtained from chemical desorption tests conducted o.^on-
site soils will be considered in determining if a differentf|j£oil
cleanup level should be established. V;
d. Treatment by air stripping and reinjection of groundwater extracted
on-site and from off-site well RW-25. If reinjection or reuse is
attempted and determined to be infeasible by the Regional Beard,
the water will be treated using air stripping and discharged into
storm drains leading to Canoas Creek.
e. Nozzle aeration of groundwater extracted from off-site wells except
well RW-25 and then discharge into storm drains leading to Canoas
Creek.
f. A goal of 100 percent for reusing off-site groundwater. Considering
the short term nature (approximately 2 years) of the bulk of the
dischargers' off-site extraction, the time required to construct
necessary reuse facilities, and that most potential users need water
only on an intermittent basis, the dischargers' ability to implement
a program for reusing a significant portion of their extracted
groundwater will be limited.
g. A laboratory and field study of biodegradation of on-site chemicals.
h. A re-evaluation of the feasibility and effectiveness of. on-site
groundwater flushing. This evaluation will be required in the five-
year remedial program evaluation required under Provision 2.h of this
Order if the . cleanup efforts described above cannot reduce
concentrations in on-site groundwater to safe drinking water levels.
i. A deed restriction. The dischargers shall be required to file a deed
restriction prohibiting use of on-site groundwater for drinking water
and limiting other subsurface activities in order to protect and
maintain the integrity of the slurry wall. The deed restriction
shall remain in place until safe drinking water levels are achieved
on-site.
j. Additional monitoring wells. Additional monitoring wells will be
required to define the boundaries of the plume in the area bordered
by Bernal Road, Via del Oro, Great Oaks Boulevard,'and Santa Teresa
Boulevard. Piezometers may also be required to determine extraction
well capture zones. _
k. Long-term monitoring (for approximately 30 years) .after cleanup
levels are achieved. . "
16. Final Cleanup Levels. The cleanup level for off-site aquifers is HI-0.25
as clarified in Specification B.3 and in Table 1 of the groundwater self-
• monitoring plan attached to this Order. The cleanup goal for the on-site
aquifers is the DHS drinking water action level or Maximum Contaminant
Level (MCL), whichever is more stringent, f or eacK "of the following
chemicals: TCA, DCE, Freon-113, and xylenes. The cleanup goal for PCE
is 2 ppb based on the proposed State MCL. No action levels or MCLs have
been established for acetone or IPA. The final cleanup goal for acetone,
based on the oral reference dose in the Integrated Risk Management System
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SITE CLEANUP REQUIREMENTS - FAIRCHILD-SAN JOSE FINAL CLEANUP
^ (IRIS) Is 3500 ppb. The final cleanup goal for IPA is 3|250 ppb. This
,,value is based on the DHS Site Specific Remediation Criterion for IPA, as
explained in Table 2 of the Groundvater Self-Monitoring Elan attached to
this Order. These cleanup levels and goals are at or belovi, drinking water
.health criteria, action levels, and standards and will assume preservation
of beneficial uses by maximizing the quality of groundvater to the maximum
extent feasible. <
The soil remediation goal is 1 ppm each for TCA, DCE, PCE, Freon-113, and
xylenes. A goal is set due to the technical uncertainties associated with
remediation of soil by means other than excavation and disposal which is
no longer feasible due to prohibitive cost and is not the preferred
remediation method as it does not treat the soil or reduce the volume of
chemicals. This goal will be re-evaluated based on the results of in-situ
soil aeration and chemical desorption test results for the soil and
evaluation of cleanup efforts.
17. Future Changes to Cleanup Levels. The discharge?:*, are expected to achieve
the cleanup goals of this final cleanup plan within 5 years. If new
information indicates cleanup levels cannot be reasonably .attained or can
be reasonably surpassed, the Regional Board will decide if further final
cleanup actions beyond those completed shall be fnplemented at this site,
based to a significant degree on the information developed pursuant to this
Order. If changes in health criteria, administrative requirements, site
conditions, or remediation efficiency occur, the dischargers will submit
an evaluation of the effects of these changes on cleanup levels specified
in Specification B.3, B.A, and B.6 and on Tables 1 and 2 of the groundwater
self-monitoring plan attached to this Order.
The Regional Board recognizes that the dischargers have already performed
extensive investigative and remedial work on-site and off-site and that
the dischargers are being ordered hereby to perform substantial additional
remedial tasl.... It is in the public interest to have the discharger?
undertake such remedial actions promptly and without prolonged litigation
or the expenditure of public funds. The Regional Board recognizes that
an important element in encouraging the dischargers to invest substantial
resources in undertaking such remedial actions is to provide the
dischargers with reasonable assurances that the remedial actions called
for in this Order will be the final remedial actions required to be
undertaken by the dischargers. On the other hand, the Regional Board also
recognizes its responsibility to protect water quality, public health, and
the environment and that future developments could indicate that some
additional remedial actions may be necessary. The Regional Board has
considered and balanced these important considerations, and has determined
that the remedial actions ordered herein repres mt the Regional Board's
best, current Judgment of the remedial act*
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SITE CLEANUP REQUIREMENTS - FAIRCHILD-SAN JOSE FINAL CLEANUP
evaluated, by the Regional Board in issuing this Order in determining
whether such :addit£onal remedial actions are appropriate and necessary.
18. Groundwater Conservation. On July 21, 1988, the State Board adopted
Resolution, No. 88-88. which required that Fairchild and IBM remediation
plans must result in beneficial use of or recharge to the Santa Teresa
Basin of a significant amount of extracted groundwater. If use or recharge
of significant amounts is not proposed for the period after January 31,
1989, the dischargers must fully justify reasons for not using or
recharging the groundwater. The Justification must also demonstrate why
continued pumping is necessary from the standpoints of public health,
protection of potential and present beneficial uses, maintaining high
quality water, and providing the maximum benefit to the people of the
State.
The dischargers currently propose to treat the bulk of off-site groundwater
by nozzles with no additional use prior to discharge to storm drains
leading to Canoas Creek; however, the dischargers are evaluating the
feasibility of reusing the groundwater resulting from the cleanup
activities.. If an opportunity for additional reuse occurs, the dischargers
will evaluate that potential reuse based on the conditions set forth under
the California Water Code Section 13550.
The Regional Board intends to strongly encourage, and require to the extent
allowed by law, the maximum reuse of extracted groundwater feasible either
by the dischargers or other public or private water users. This Order
requires groundwater conservation and reuse measures to be consistent with
State Board Order 88-88. These measures include reinjection or reuse of
groundwater extracted from on-site wells and from off-site well RW-25, if
feasible, and requiring the dischargers to submit a plan for reusing
extracted groundwater, with a reuse goal of 100 percent. Due to factors
beyond the dischargers' control, the dischargers may be unable to attain
... the 100% reuse goal established by this Order. The dischargers will not
be found to be in violation of this Order if documented factors beyond the
: control of the dischargers prevent the dischargers from attaining 100%
reuse, provided that the dischargers made a good faith effort to attain
that goal.
19. Evaluation of Final Plan. In accordance with the Health and Safety Code
Section 25356.1, Section 121 of CERCLA, the final remedial action plan
(including the RAP submitted by the dischargers on October 7, 1988, the
Addendum dated December 16, 1988, this Order, and Order No. 89-15 (NPDES
Permit No. CA 0028185) is equivalent to a feasibility study; satisfies the
requirements of the California Water Code Section 13304 and is protective
of human health and the environment; attains Applicable or Relevant and
Appropriate Requirements (ARARs); utilizes permanent solutions and
alternative treatment technologies and resource recovery technologies to
,. the maximum extent possible for short term effectiveness; is implementable;
is cost effective; is acceptable based on State regulations, policies, and
guidance; reduces toxicity, mobility, and volume of pollutants; and
addresses public concerns.
20. State Board Resolution 68-16. On October 28, 1968, the State Board adopted
Resolution No. 68-16, "Statement of Policy with Respect to Maintaining High
Quality Waters in California". This policy calls for maintaining the
existing high quality of State waters unless it is demonstrated that any
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SITE CLEANUP REQUIREMENTS '- FAIRCHILD-SAN JOSE FINAL CLEANUP
change vr^ld be consistent with the maximum public benefit and not un-
reasonably^ affect beneficial uses. This is based on a Legislative finding,
coiptained;ein Section 13000, California Water Code, which states in part
that it iSi State policy that "waters of the State shall be regulated to
attain the highest water quality which is reasonable.* The original
discharge "(of wastes to the groundwater at this site was in violation of
this policy; therefore, the groundwater needs to be restored to its
original bigh quality to the extent reasonable. Based on available
information, as found in the dischargers' technical reports "Remedial
Action Plan, Fairchild Semiconductor Corporation, San Jose Facility" dated
September 1987 and revised Hay 1988 and October 1988, the change in water
quality does not unreasonably affect beneficial uses and is consistent with
the maximum public benefit as defined in State Board Resolution No. 68-16.
This limited degradation would not exceed any established water quality
policies; the remediation water quality levels proposed for off-site are
well below current applicable health criteria; and the levels do restore
the quality of the groundwater to the extent reasonable given technical
And economic constraints. These constraints include the high additional
"incremental costs for removal of small amounts of additional pollutants
end the need to minimize the removal of groundwater to achieve acceptable
cleanup levels.
21. Water Supply Veils. Great Oaks Water Supply Company drinking water supply
well GO-13 was contaminated with pollutants from the dischargers' release.
GO-13 was removed from service in December 1981 and has since been
destroyed and sealed. As a result of interim cleanup, groundwater in Great
Oaks well GO-A, a drinking water supply well located down-gradient from
the site, has remained free of detectable concentrations of volatile
organic chemicals.. TCA concentrations of up to 5 ppb may reach the B
aquifer in the vicinity of GO-4 and lower concentrations may reach the B
aquifer in the vicinity of other down-gradient Great Oaks wells after the
dischargers have obtained an HI of 0.25 in off-site aquifers and discon-
tinues groundwaf : extraction. (The DHS drinking water action level for
TCA is 200 ppb.)
22. Pumping and recharge -activities within the Santa Teresa Groundwater Basin
by others affect vertical and lateral hydraulic gradients and may impact
plumf Fiigratirn control at the Fairchild site and off-site. Furthermore,
the overal1 imbalance in the hydrologic budget for the Santa Teresa
Groundwater Basin is beyond the sole control of the dischargers.
23. The final remediation plan is conceptual and provides a basis for remedial
~ -design.
24. Development of this final cleanup plan was based on the Regional Board's
evaluation of seven years of water and soil quality data. Samples have
been collected and analyzed by the Regional Board to confirm the validity
ol data generated by the dischargers. Some of the data was reviewed by
EPA and found to be acceptable for limited purposes. The quality of this
data has been taken into consideration in developing the final cleanup
plan.
25. The Regional Board adopted a revised Water Quality Control Plan for the
San Francisco Bay Basin (Basin Plan) on December 16, 1986. The Basin Plan
contains water quality objectives and beneficial uses for South San
Francisco Bay and contiguous surface and groundwaters.
8
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SITE CLEANUP REQUIREMENTS - FAIRCHILD-SAN JOSE FINAL CLEANUP
26. The existing and jjptential beneficial uses of the groundwater underlying
and adjacent to the facility include: ^"'
':''•' ' y'-i"
a. Industrial process water supply ^
b. Industrial service water supply ~ ',$
c. Municipal and domestic water supply ;|
d. Agricultural vater supply ^
27. The dischargers have caused or permitted, and threaten to cause or permit,
waste to be discharged or deposited where it is or probably will be dis-
charged to waters of the State and creates or threatens to create a
condition of pollution or nuisance. On-site and off-site final containment
and remediation measures need to be implemented to alleviate the threat
to the environment posed by the plume of pollutants.
28. This action is an order to enforce the laws and regulations administered
by the Regional Board. This action is categorically exeapt .from the
provisions of the CEQA pursuant to Section 15321 of the Resources Agency
Guidelines. /. t,
29. The Regional Board has notified the dischargers and interested agencies
and persons of its intent under California Vater Code Section &3304 and
California Health and Safety Code Section 25356.l(d) to prescribe Site
Cleanup Requirements and to issue a remedial action plan for tie discharge
and has provided them with the opportunity for a public hearing and an
opportunity to submit their written views and recommendations. .
30. The Regional Board, in a public meeting, heard and considered all comments
pertaining to the discharge.
IT IS HEREBY ORDERED, pursuant to Section 13304 of the California Water Code and
Section 25356.1 of the California Health and Safety Code, that the dischargers
shall cleanup and abate the effects described in the above findings as follows:
A. PROHIBITIONS
1. The discharge of wastes or hazardous materials in a manner which will
degrade water quality or adversely affect the beneficial uses of the
waters of the State is prohibited. *.,
2. Further significant migration of chemicals above cleanup levels as
described in.Specification B.3 and B.4 through subsurface transport
to waters of the State is prohibited.
3. Activities associated with the subsurface investigation and cleanup
which will cause significant adverse migration of chemicals are pro-
hibited.
B. SPECIFICATIONS
1. The storage, handling, treatment or disposal of soil or groundwater
containing chemicals shall not create a nuisance as defined in
Section 13050(m) of the California Vater Code.
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SITE CLEANUP REQUIREMENTS - FAIRCHILD-SAN JOSE FINAL CLEANUP
2. The dischargers shall conduct monitoring activities as needed to
dffine and detect changes in the locakoiydrogeologic conditions and
^the lateral and vertical extent of sii. and groundwater containing
'chemicals. Should monitoring resales show evidence of plume
migration above cleanup levels as described in Specification B.3.
and, during remedial action, above 0.$ ppb DCE in Zones 2 and 3 as
shown in Figure 1 of the Self-Monitorii £ Plan attached to this Order,
additional plume characterization may se required.
3. Final cleanup levels for chemical concentrations in off-site veils
containing chemicals from the dischargers' facility shall be equal
to or less than an HI of 0.25.
The HI is calculated as shown:
n
concentration of chemical "i*
safe drinking water level for chemical "i"
i-1 •
At the time of this Order, EHS Drinking Water Action Levels are the
most stringent safe drinking water criteria for chemicals detected
off-site. DHS Action Levels shall be used to calculate the off-site
HI unless Maximum Contaminant Levels (HCLs) or other final, duly-
promulgated drinking water standards become the most stringent safe
drinking water level.
4. Final groundwater cleanup goals in on-site aquifers shall be equal
to or less than the DHS drinking water action level or Maximum
Contaminant Level, whichever is more stringent, for each of the fol-
lowing chemicals: TCA, DCE, PCE, Freon-113, and xylenes. No action
levels or MCLs have been established for acetone or IPA. The final
cleanup goal for acetone, based on the oral reference does in the
Integrated Risk Management System (IRIS) is 3500 ppb. The final
cleanup goal for IPA, based on the DHS Site Specific Remediation
Criterion for IPA as explained in Table 2 of the Groundwater Self-
Monitoring Plan attached to this Order, is 2,250 ppb.
5. Final chemical concentrations shall r,c be found to exceed the
ptfpropriate cleanup level based on f'ne moving annual average of
analytical results as determined at the end of each quarter.
The moving annual average shall be calculated each quarter for each
well using the 4 most recent quarterly sampling"results. If the
moving annual average for ary well in any quarter increases by 50%
or more relative percent dif .erence (RPD) from the previous quarter,
which will be considered a baseline quarter, then the dischargers
shall inform the Regional Board by telephone of such an increase as
soon as the dischargers or the dischargers' agent have written
laboratory results indicating such an increase. The dischargers
shall confirm this notification in writing within two weeks of the
telephone notification. As part of the quarterly monitoring report
for the quarter in which the concentration increase occurred, the
dischargers shall submit to the Regional Board a technical report
acceptable to the Executive Officer containing an evaluation of the
occurrence and proposal for corrective action. The report shall
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SITE CLEANUP REQUIREMENTS - FAIRCHILD-SAN JOSE FINAL CLEANUP
include a proposalffor increased monitoring and an evaluation of the
costs'! benefits atuij drawbacks of modifying active hydraulic cleanup
and ^containment measures in comparison with a continued monitoring
alternative. * ^
jit- ' •"•••
iff* '• '
The quarter prior £o the quarter in which an RPD of 50% or greater
was detected shall be established as the baseline quarter. The
moving annual average for the baseline quarter shall be established
as the baseline average. If the second quarterly average following
the baseline quarter is still 50% or more RPD above the baseline
average and the dischargers have not implemented a corrective action
program, and the concentrations are above final cleanup levels, then
a threatened violation is present and the dischargers shall inform
the Regional Board of the causes of this threatened violation. If
the third quarterly average is an increase of 50% or more RPD from
the baseline average and concentrations are above final cleanup
levels then the dischargers shall be considered to be in violation
of this order and shall inform the Regional Board of how and when
the dischargers will regain compliance.
6>. The dischargers shall cleanup soil to a goal of 1 ppm for each of
# the following chemicals: TCA, DCE, xylenes, Freon-113, and PCE.
This goal may be modified by the Executive Officer if the dischargers
demonstrate with site specific data that higher levels of chemicals
in the soil will not threaten the quality of waters of the State or
that cleanup to this level is infeasible and human health and the
environment are protected.
7. The dischargers shall optimize, with a goal of 100%, their use of
the groundwater extracted from their groundwater cleanup activities
to aid the cleanup and minimize water level declines. The dischargers
shall not be found to be in violation of this Order if documented
factors beyond the dischargers' control prevent the dischargers from
.attaining 100% reuse, provided thrt the dischargers have made a good
'"faith effort to attain that- goal. Factors effecting the dischargers'
ability to achieve the reuse goal include but are not limited to:
(1) 'whether the extracted groundwater must be disposed of in
accordance with Resource, Conservation, and Recovery Act (RCRA)
regulations, and (2) cooperation from local water suppliers in
reusing the water. -
8. Off-site compliance points shall be established at all monitoring
wells which at any time are outside the 0.25 HI plume boundary.
After on-site activities except for monitoring are completed, on-
site compliance points shall be established at all wells which are
or will be within the boundaries of the slurry wall. Notwithstanding
this specification, the dischargers may seal monitoring wells outside
the 0.25 HI plume boundary upon approval of the Executive Officer.
9. The dischargers shall maintain extraction wells VCC-20, RW-2, RW-
22, and RU-25 in operable condition until the cleanup levels are
attained throughout the entire plume area.
10. The dischargers shall implement the final cleanup plan described in
Findings 12, 13, 14, 15, and 16, as modified by this Order.
11
-------
c.
~~2v:
'• £.
2.
the
-"»*.tCW
now
*- «»^,
ty
~u«ntifv j c«e - *'t-«ole .. ""•'ts PBTTP.,
J ««« /n *• t3,UM«« « *e «2S- s-">«t €
«*sic 3. ' **is. 1990 tth«
!echnicai J^cnHanu-r^
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SITE CLEANUP REQUIREMENTS - FAIRCHILD-SAN JOSE FINAL CLEANUP
t '
effect of: relnjection on ? the plume boundaries, and
presenting the results frpm the well clogging study.
This technical report may&be submitted as part of the
quarterly^ monitor ing repojt that is due May 15, 1990.
If re injection is determined to be infeasible, such
determination shall be made by the Regional Board.
b. IN-SITU SOIL AERATION :?f
i.
1) COMPLETION DATE: March 1, 1989
TASK 4: IN-SITU SOIL AERATION SYSTEM INTERIM DESIGN
REPORT. Submit a technical report acceptable to the
Executive Officer documenting the construction and
operation of the in-situ soil aeration system for
treating soils with TCA concentrations greater than 10
ppm. The report shall contain soil boring logs, well
construction details, results from soil chemical testing,
and air monitoring results (laboratory chemical analyses ,
OVA monitoring,: and flow measurements). The report
shall also document construction and operation of any
necessary additional on-site groundwater extraction well
or wells.
2) COMPLETION DATE: August 15, 1989
TASK 5: MODIFICATIONS TO IN-SITU SOIL AERATION SYSTEM.
Submit a technical report acceptable to the Executive
Officer evaluating the effectiveness of the existing
system in removing volatile chemicals from soils
containing greater than 1 ppm TCA and proposing any
modifications needed to cleanup soils containing greater
than 1 ppm TCA. The report may be submitted as part of
the quarterly status report that.-is due August 15, 1989.
3) COMPLETION DATE: November 15, 1989 .
TASK 6: IN-SITU SOIL AERATION SYSTEM FINAL DESIGN
REPORT. Submit a technical report acceptable^ to the
Executive Officer documenting the completion" of any
modifications to the in-situ soil aeration system
identified in Task 5. This technical report may be
submitted as part of the quarterly monitoring report due
on"November 15, 1989.
4) COMPLETION DATE:. 45 days prior to expected termination
of the in-situ aeration system
TASK 7: PROPOSAL TO TERMINATE OPERATION OF THE IN-SITU
SOIL AERATION SYSTEM. Submit a technical report
acceptable to the Executive Officer containing a proposal
for terminating operation of the in-situ soil aeration
system and the criteria used to justify termination of
system operation. The proposal shall include cycling
of the system to determine if concentrations increase
after the system is temporarily shut down< and then reac-
13
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SITE CLEANUP REQUIREMENTS '- FAIRCBILO-SAN JOSE FINAL CLEANUP
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SITE CLEANUP REQUIREMENTS - PAIRCHILD-SAN JOSE FINAL CLEANUP
";'*.' '
TASK 12: RESULT^ OF DESORPTION TESTING. Submit a
technical report 'acceptable to the Executive Officer
containing the results from the desorption testing. This
report may be submitted as part of the quarterly status
report due August its, 1989. '
e. ADDITIONAL OFF-SITE INFORMATION
1) COMPLETION DATE: May 1, 1989
TASK 13: PROPOSAL FOR NEV MONITORING WZLLS. Submit a
technical report acceptable to the Executive Officer
containing a proposal for determining the boundaries of
the plume in the area bounded by the following streets:
Bernal Road, Via del Oro, Great Oaks Boulevard, and Santa
Teresa Boulevard.
2) COMPLETION DATE: July 3, 1989
TASK 14':•' DEFINITION OF PLUME BOUNDARIES. Submit a
technical report acceptable to the Executive Officer
documenting the completion of tasks identified in the
technical report submitted for Task 13.
f. CURTAILING OFF-SITE CROUNDWATER EXTRACTION
1) COMPLETION DATE: four months prior to proposed
implementation of off-site groundvater
extraction curtailment
TASK 15: , OFF-SITE WELL PUMPING CURTAILMENT CRITERIA
AND PROPOSAL. Submit a technical report acceptable to
the Executive Officer which contains a proposal for
curtailing pumping from off-site groundwater extraction
wells and the criteria used to justify such curtailment.
The proposal shall include temporary curtailment of
extraction well operation for an extended period of time
to study the effects on pollutant migration prior las well
abandonment. This report should identify the method,
specific monitoring wells, and the basis for the time
frame to be used to determine that final cleanup levels
have been reached and that the potential for increases
above cleanup levels in concentrations is minimal. This
report shall include supporting data for and an
evaluation of water 'quality in areas believed to be
remediated. As the dischargers Intend to curtail use
of extraction veils in a sequential manner as cleanup
levels are achieved, the report shall contain an evalua-
tion of capture zone confirmation for remaining
extraction wells and a proposal for installation of
additional piezometers and monitoring wells as needed.
This report shall also provide for soil borings in the
saturated and unsaturated portions of the B aquifer to
determine residual soil chemical concentrations.
Notwithstanding this provision, the dischargers«ay begin
15
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CLEANUP REQUIREMENTS - FAIRCHILD-SAN JOSE FINAL CLEANUP
curtailing the pumping of extraction wells RV-19(B) and
Ry-27(B), in accordance with the proposal contained in
the RAP submitted October 1988, without submitting a
technical report. (
2)
COMPLETION DATE:
SO days after Regional Board approves
off*site curtailment
g-
TASK 16: OFF-SITE CURTAILXENT IMPLEMENTATION. Submit
a technical report acceptable to the Executive Officer
documenting completion of the necessary tasks identified
in the technical report submitted for Task IS.
CURTAILING ON-SITE CROUNDWATER EXTRACTION
1)
2)
COMPLETION DATE:
two months prior to proposed
implementation of on-site groundwater
extraction curtailment
TASK 17: ON-SITE WELL PUMPING CURTAILMENT CRITERIA AND
PROPOSAL. Submit a technical report acceptable to the
Executive Officer containing a proposal for curtailing
pumping from on-site groundwater extraction wells and
the criteria used to justify such curtailment. This
report shall identify the method and the basis for the
time frame to be used to determine that final cleanup
levels have been reached and that the potential for
increases above cleanup levels in concentrations is
minimal. The report shall contain an evaluation of the
feasibility of reducing on-site groundwater concentra-
tions to equal to or less than tv i cleanup levels listed
in Table 2 of the groundwater ^elf-monitoring plan. The
report shall also propose . revised analysis based on
actual final soil and groundwater concentrations for
estimating future chemical migration through the slurry
wall and through the on-site AB aquitard.
If the dischargers determine that it is not feasible to
achieve these cleanup levels, the report shall evaluate
the maximum reductions in on-site groundwater concentra-
tions that can be achieved. Additionally, the report
shall contain a proposal for insuring the long-term
integiity of the slurry wall, specifically addressing
the potential loss of fines if the hydraulic gradient
across the slurry wall becomes excessive.
COMPLETION DATE:
h.
1)
30 days after Regional Board approves
on-site curtailment.
TASK 18:. ON-SITE CURTAILMENT IMPLEMENTATION. Submit
a technical report acceptable to the Executive Officer
documenting completion of the necessary tasks identified
in the technical report submitted for Task 17.
COMjrLiriON DATE: January 18, 1994
Hazardous Wa
"formation Re
US EPA Region :
Philadelphia, P
16
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