United States
Environmental Protection
Agency,
Office of
Emergency and
Remedial Response
EPA/ROD/R09-89/031
March 1989
Superfund
Record of Decision
Intel (Mountain View), CA
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50272-101
REPORT DOCUMENTATION 1'. REPOATNO. 12.
PAGE EPA/ROD/R09-89/031
3. A8c:1p'enr. AcC88810n No.
4. TItle and Sub1ItIe
SUPERFUND RECORD OF DECISION
Intel (Mountain View Plant), CA
First Remedial Action
7. Aulhor(a'
5. Report Oate
06/09/89
I.
I. P8rfonning Orgenlzadon Rapt. No.
8. P8rf0nnlng Orgelnlzadon N8m8 end AddI888
10. ProjectlTMk/WOItI Unit No.
11. Contr8ct(C) cw GnnI(G) No.
(C)
(G)
12. Sponeortng 0rpnIDII0n Nenw and Addrw8
U.S. Environmental Protection
401 M Street, S.W.
Washington, D.C. 20460
13. Type of Report . P8r1od eoVW8d
Agency
800/000
14.
15. Suppi8menl8ly No...
18. Ab81r1lCt (UftI: 200 -Ida)
The Intel (Mountain View Plant) site is one of three Superfund sites that are being
remediated concurrently. The other two sites are Fairchild Semiconductor (Mt. View) and
Raytheon. The sites are located in the Middlefield/Ellis/
Whisman (MEW) Study Area in Santa Clara County in the city of Mountain View, California.
. Land use in the area is primarily light industrial and commercial, with some residential
areas~ There are no natural surface drainage features within or surrounding the site;
most of the runoff is intercepted by a storm drain system and discharged to an offsite
creek. Various industrial activities were conducted in the vicinity of the site,
including semiconductor manufacturing, metal finishing operations, parts cleaning,
aircraft maintenance, and other activities requiring the use, storage, and handling of a
variety of chemicals, particularly solvents. Site investigations at. several of these
facilities during 1981 and 1982 revealed significant soil and ground water conta~nation
by toxic chemicals, primarily VOCs. The primary causes of the contamination were
leaking storage tanks and lines, and poor management practices. Before and during.
additional site investigations, which were conducted under a 1985 Consent Order, interim
cleanup actions were conducted at the site by Fairchild, Intel, and Raytheon. These
included tank removals, soil removal and treatment,well sealing, construction of- slurry
(See Attached Sheet)
17. Ooa8nent ANI.,. ... 088crIp1t1f8
Record of Decision - Intel (Mountain View), CA
First Remedial Action
Contaminated Media: soil, gw
Key. Contaminants: VOCs (PCE, TCE, TCA, toluene, xylenes), organics (phenols)
b. Id8ndll8r8lOpen.EndecI T-
c. CooA TI ReIdIGroup
11. AVlllabilty St-..nt
18. S8c:urtty a.u (ThI8 Report)
None
20. S8c:urtty CI- (ThI8 Pllge) .
Nnno:>
21. No. o' pagee
9')
I
22. Price
(See ANSIoZ38.18)
See 'M/rUCdona on Re-
272 (4-77)
(Formerty NTlS-35)
Department 01 Convnerce
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EPA/ROD/R09-89/031 .
Intel (Mountain View Plant), CA
First Remedial Action
16.
Abstract (Continued)
walls, and hydraulic control and treatment of local ground water. The primary
contaminants of concern affecting the site are VOCs including TCE, TCA, PCE, toluene,
and xylenes; and other organics including phenols.
The selected remedy for this site includes in situ vapor extraction with treatment by
vapor phase GAC of contaminated soil found within the Fairchild and Raytheon slurry
walls. There may be some limited soil excavation and treatment by aeration for some
areas outside of the slurry walls with onsite disposal of residues in the excavated
area; ground \iater pumping and treatment using air stripping, and in some cases liquid
phase GAC, with emissions controls consisting of GAC vapor phase carbon units, followed
by reuse of the ground water (reuse options including reinjection are being developed)
and, if necessary, discharge to surface water; sealing of any conduits or potential
conduits to protect the deep aquifer; and ground water monitoring. The present worth
cost for this remedial action is $49,000,000 to 56,000,000, which includes O&M costs.
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FAIRCHILD, INTEL, AND RAYrHEON SITES
MIDDLEFIELD/ELLIS/WHISMAN (MEW) STUDY AREA
MOUNTAIN. VIEW, CALIFORNIA
RECORD OF DECISION
United States Environmental Protection Agency
Region IX -- San Francisco, California
June 9, 1989
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FAIRC3ILD, INTEL, AND RAYTHEON SITES
MIDDLEFIELD/ELLXS/WHXSMAJi (MEW) STUDY AREA
MOUNTAIN VIEW, CALIFORNIA
RECORD OY D1CIBIOM
United State* Environmental Protection Agency
Region IX -- San Francisco, California
May 1989
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RECORD OF DECISION
TABLE OF CONTENTS
SECTION PAGE
Table of Contents . i
Table of Figures and Tables ii
Declaration iii
1.0 Site Location and Description 1
2.0 Site History 2
3.0 Enforcement 3
4.0 Community Relations 4
5.0 Decision Scope 4
6.0 Nature and Extent of Contamination 5
7.0 Baseline Site Risks 6
8.0 Changes to the Proposed Plan 8
9.0 Description of Alternatives 9
10.0 ARARs . 14
11.0 Other Criteria Considered 18
12.0 Summary of Alternatives Analysis 21
13.0 The Selected Remedy 22
14.0 Statutory Determinations 24
— Attachments —
Administrative Record Index
Responsiveness Summary
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DCORD 01' DBCIBIOJf
~ABLB 01' COIl'1'BJr1'B
-- I'igur.. --
FIGURE/TABLE
1-1
1-2
6-1
9-1
6-1 .
i
10-1
11-1
12-1
Site LOcation
Buildinq occupants
Location of MEW Plume
Schematic of Subsurface Zones
--
~aJ)1..
--
--- Chemicals of Concern
--- Federal and State Groundwater Standards
--- Groundwater Criteria To Be Considered
--- Criteria for the Evaluation
of Remedial Alternatives
ii
FOLLOWING PAGE
1
1
5
9
5
15
19
21
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RECORD OF DECISION
DECLARATION
Site Name and Location
Fairchild, Intel and Raytheon Sites, Middlefield/Ellis/Whisman
(MEW) Study Area, Mountain View, California
Statement of Basis and Purpose
This decision document presents the selected soil and groundwater
remedial actions for the Fairchild, Intel, and Raytheon National
Priority List (NPL) Sites in the Middlefield/Ellis/Whisman (MEW)
Study Area of Mountain View, California. The selected remedial
actions will also apply to the area-wide groundwater
contamination and to other areas of soil contamination in the MEW
Study Area, as appropriate. The remedial actions have been
developed in accordance with the Comprehensive Environmental
Response, Liability, and Compensation Act (CERCLA), as amended by
the Superfund Amendments and Reauthorization Act (SARA), and, to
the maximum extent practicable, the National Contingency Plan
(NCP). This decision is based upon the administrative record for
this site. The attached index identifies the items which comprise
the administrative record upon which the selection of the
remedial actions are based.
Description of the Remedies
The selected soil remedy is in-situ vapor extraction with
treatment by vapor phase granular activated carbon, and
excavation with treatment by aeration. Most of the vapor
extraction will take place within the existing Fairchild and
Raytheon slurry walls which contain the bulk of the site soil
contamination. Several smaller areas outside of the slurry walls
will also be remediated by in-situ vapor extraction. The cleanup
goals for soils are l part per million (ppm) trichloroethene
(TCE) inside the slurry walls and 0.5 ppm TCE outside of the
slurry walls. The soil cleanup goal is based on the amount of
contamination that can remain in the soil and still maintain the
groundwater cleanup goal in the shallow aquifers (outside the
slurry walls). Further explanation of the different cleanup goals
is provided on page 22 of this document, in Section 13 on The
Selected Remedies.
The groundwater remedy is extraction and treatment. Extracted
groundwater will be treated by air stripping towers. Airborne
emissions will meet all Bay Area Air Quality Management District
emission standards. It is anticipated that emission controls by
granular activated carbon will be required once the full remedy
is implemented. The extracted groundwater will be reused to the
iii
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maximum extent feasible, with a qoal of 100% reuse. Extracted
water which cannot be reused will be discharqed to local' streams..
Allowable discharqes to local streams will be requlated by the
National Pollutant Dischar'ge Elimination system (NPDES) of the
Clean Water Act.
The qroundwater cleanup qoals are 5 parts per billion (ppb) TCE
for the shallow aquifers (which are not currently used for'
drinkinq water) and 0.8 ppb.TCE for the deep aquifers which are
used for drinkinq water. Attainment of these levels will also
assure cleanup of the other volatile orqanic compounds to at
least their respective Maximum Contaminant Levels (HCLs). The
shallow aquife;r cleanup qoals also apply to the aquifers inside
the slurry walls. .
The remedy includes the identification and sealinq of any
potential conduit wells. Several abandoned aqriculture wells
which acted as conduits for contamination to miqrate from the
shallow aquifers to the deep aquifers have already been sealed.
Additional wells have been identified for sealing and others may
be identified which will also require sealinq.
The remedy also includes maintaininq inward and upward hydraulic
qradients (by pumping and~reatment) inside the slurry walls and
reqular monitoring of aquifers within and adjacent to the slurry
walls to monitor the integrity of each slurry wall system.
Maintaininq inward and upward hydraulic qradients will control.
contaminants from .scapinq due to slurry wall failure. Selected
wells will be monitored for chemical concentrations and water
levels.
The soil remedy is expected to be in operation between 1 to 6 -
years. The qroundwater remedy for the shallow aquifers may be in
operation for as long as 46 years or into the indefinite future,
because of the physical and chemical nature of the aquifers. The
qroundwater remedy for the deep aquifers is estimated to be in
operation for at least 2 years and possibly as lonq as 45 years.
There will be reqular monitorinq of the qroundwater and slurry
walls durinq the life of the remedy.
iv
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Declaration
The selected remedies are protective of human health and the
environment, attain Federal and state requirements that are
applicable or relevant and appropriate to the remedial actions,
and are cost-effective. With respect to contamination in
qroundwater and soil, the statutory preference for remedies that
. employ treatment, reduce toxicity, mobility or volume as a
principal element, and utilize perm~nent solutions and
alternative treatment technologies to the maximum extent
practicable is satisfied.
Because of the anticipated lenqth of time to achieve the cleanup
qoals and. the uncertainty whether the cleanup qoals. .can be
achieved, both the technoloqies and the cleanup qoals will be
reassessed every 5 years. .
'~aMJfrl/rJ~~
Daniel W. McGovern
Reqional Administrator
v
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RBCORD OP DBCISIOB
DBCISIOB SUXKaRY
1.0
SITE LOCATION AND DESCRIPTION
The Middlefield/EllisfWhisman (MEW) Study Area is located in
Santa Clara County in the city of Mountain View, California.
The site is divided into a Local Study Area (LSA) and a Regional
study Area (RSA). Figure 1-1 identities the LSA and RSA, along
with local roads and landmarks. The LSA cQnsists of three
National Priority List (NPL) sites (Fairchild, Intel and
Raytheon), as well as several non-Superfund sites. The LSA
encompasses about 1/2 square mile ot"the RSA and contains
primarily light industrial and commercial areas, with some
residential areas west of Whisman Road. The RSA encompasses
approximately 8 square miles and includes Moffett Naval Air
station (an NPL site) and NASA Ames Research Center, along with
light industrial, commercial, agricultural, park, golf course,
undeveloped land, residential, motel and school land uses.
Various owners or occupants in the area around the intersections.
of Middlefield Road, Ellis Street, Whisman Road, and the Bayshore
Freeway (U.S. Highway 101), are or were involved in the
manufacture of semiconductors, metal tinishing operations, parts
cleaning, aircraft maintenance, and other activities requiring
the use of a variety of chemicals. Local tacilitieswith current
occupants are presented on Figure 1-2. Site investigations at
several of these facilities have revealed the presence of toxic
chemicals in the subsurface soils and groundwater. To investigate
the extent of groundwater contamination emanating from the LSA,
and soil contamination at their respective facilities, Fairchild,
Intel, and Raytheon performed a Remedial Investigation and a
Feasibility Study of potential remedial alternatives under the
direction of EPA. .
There are no natural surface drainage teatures within the Local
Study Area. The nearest significant natural surface drainage
features of the Regional Study Area are Stevens Creek to the west.
and Calabazas Creek to the east..Calabazas Creek is located
approximately tour miles east of the MEW Study Area. Stevens
Creek forms the western boundary of the Regional Study Area. Both
discharge into the San Francisco Bay. Surface water runoff from
most ot the RSA and allot the LSA south ot the Bayshore Freeway
is intercepted by a .torm drain system and is discharged into
Stevens Creek. To the north ot the Bayshore Freeway, most o~ the
runoff t.~om MottettField Naval Air Station is collected by a .
storm drain system that ultimately discharges to ~uadalupe Slough
of San Francisco Bay. Runoff from the northwestern portion of
Moffett Field discharges into Stevens Creek. .
1
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MIDDLEFJELD-ELLIS- WHISMAN AREA
Sit. Location
Flgur. 1-1
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BUILDfNG
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IEW, CALIFOONIA
Flgur. 1-2
MIDDLE .
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DRAwING NUMIIE
82-023-[627 R
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The Local and Regional study Areas are underlain by a thick
sequence of unconsolidated sediments deposited into a structural
depression. The sediments are comprised of alluvial fan,
estuarine, and bay mud deposits. Repeated variations in sea
levels resulted in a complex sedimentary sequence characterized
by irreqular interbedding and interfingering of coarse and fine
grained deposits. .
Groundwater aquifers at the site are subdivided into shallow and
de.p aquifer systems, separated by a laterally extensive regional
aquitard. The shallow aquifer system comprises aquifers and
aquitards to a depth of approximately 160 feet below the surface.
Within the shallow system four primary hydroqeoloqic aquifer
zones have been identified based upon the. occurrence of aquifer
. material and a similar depth below the surface. The' shallow'
aquifer system is comprised of theA~aquifer and the underlying
B1-, B2- and B3- aquifers. The regional B-C aquitard separates
the B3-aquifers from the C-aquifer and the deep aquifer system.
CUrrent groundwater flow in aquifer zones above. the B-C aquitard
is generally to the north, toward San Francisco Bay.
2.0
SITE HISTORY
During 1981 and 1982, preliminary investigations of facilities
. within the LSA indicated significant concentrations. of
contaminants in soil and groundwater. By 1984, the Fairchild, .
Intel and Raytheon sites, located within the LSA, were proposed
for the Federal National Priorities List (NPL). By 1985, five
companies within the LSA (Fairchild, Intel, Raytheon, NEC, and
Siltec) initiated a joint investigation to document and
characterize the distribution of chemicals emanating from their
facilities. In April 1985, the California Regional Water Quality
Control Board - San Francisco Bay Region (RWQCB) adopted Waste
Discharge Requirements (WDRs) for each of the five companies. The
primary cause of the subsurface contamination was from leaking
storage tanks and lines, and poor waste management practices.
On Auqust 15, 1985, Fairchild, Intel, and Raytheon entered into a.
Consent Order with the EPA, the RWQCB, and the California
Department of Health Services (DHS). Since signing of the Consent
Order, the three companies have carried out an extensive Remedial
Investigation and Feasibility Study (RIfFS) of chemicals
emanating from the LSA and soil contamination at their respective
facilities. Work has been performed under the supervision of EPA,
the RWQCB, DHS, and the Santa Clara Valley Water District
(SCVWD). Prior to and during the site '~nvestigation, the
companies have been conducting interim clean up activities at the
site. These interim remedial actions include tank removals, 50il
removal and treatment, well sealing, construction of slurry
2
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walls, and hydraulic control and treatment of local groundwater.
NEC and Siltec declined to enter into the Consent Order and wer~
placed under RWQCB enforcement authority.
The three companies followed an approved Quality Assurance and
Quality Control (QA/QC) Plan and approved Sampling Plans. In .
addition, split samples were collected by EPA from selected wells
and. these results were compared with the companies' sampling
results. EPA determined tha.t the companies' data quality was
adequate for the purpose of the RI/FS.
The MEW Remedial Investigation Report was concluded in July,
1988. The draft Feasibility Study and EPA's Proposed Plan were
presented to the c~mmunity for review and public comment in
November, 1988. In May 1989, Special Notice letters tor the
Remedial Design/Remedial Action (RD/RA) Consent Decree were sent
out to the five (5) original companies and twelve. (12) other
Potentially Responsible Parties (PRPs).
3.0
ENFORCEMENT
The Reqional Water Quality' Control Board - San Francisco Bay
Region (RWQCB) was the lead agency until. April 1985, when the
Board referred the five companies to EPA for cleanup under
SUperfund'. In May, 1985, EPA sent general notice letters,
pursuant to Section 106 of CERCLA, to the fivecompanies.'NEC and
Siltec chose not to. participate in the RI/FS negotiations and
were referred back to the RWQCB. .In Auqust 1985, Fairchild,
Intel, and Raytheon signed an Administrative Order on Consent
with EPA, to conduct an RI/FS of the MEW area. The RWQCB and
California Department of Health Services were cosignees of the
Consent Order. .
The Consent Order and Work Plan called for a comprehensive
groundwater investigation of the MEW area and site specific
(source) investigation at Fairchild, Intel, and Raytheon. The
RWQCB issued Waste Discharge Requirements (WDRs) for NEC and
Siltec which paralleled the Consent Order schedule and
requirements.
During the course of the RI/FS, EPA gathered new information and
evaluated existing information concerning other PRPs.
During December 1987 and January 1988, EPA issued twenty-four
(24) RCRA 3007/CERCLA 104 information request letters to various
other parties in the MEW area. ~n July 1988, EPA issued a RCRA
3013 Unilateral Order to GTE-to begin an investigation of its
property, tQ determine if the company had contributed to the MEW
groundwater plume. After evaluating the 3007/104 response
le~ters, EPA sent General Notice Letters to seventeen (17) PRPs
~
3
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in September 1988. An initial PRP meeting was sponsored by EPA in
October 1988, to explain the Superfund process to the noticed
PRPs. EPA issued seven (7) additional General Notice and/or
information request letters in March 1989. EPA subsequently
issued Special Notice Letters for conducting the selected
remedies in May 1989.
4.0
COMMUNITY RELATIONS
The comment period for the Proposed Plan opened November 21,
1988, and closed January 23, 1989. A public meeting was held on
December 14, 1988 at the Crittenden Middle School in Mountain
View and was attended by approximately 75 people.
Prior to'the beginning of the public comment'period; EPA
published notices in "The View", "The Los Altos'Town Crier", "The'
Times Tribune", and the "San Jose Mercury News" (Peninsula Extra
Edition). The notices briefly described the Proposed Plan and.
announced the public comment period and the public meeting. The
notice also'announced the av_ilability of the, Proposed Plan for
review at the information repository' established at the Mountain
View Public Library.
A fact sheet describing the Proposed Plan was delivered to the
Mountain View Public Library in November, 1988., Copies of the
fact sheet were also mailed in November, 1988 to EPA's MEW
mailing list, which contains members of the, general public,
elected officia~s, and PRPs.
In addition, EPA held several workshops and briefings"in November
and December, 1988 for various community groups, the Mountain'
View City Council, and the Santa Clara County Board of
Supervisors. The workshops were used to brief community groups
and elected officials on the results of the MEW RI/FS and to
describe EPA's proposed remedial alternatives.
EPA has prepared the attached response summary, which provides
Agency responses to comments submitted in writing during the
public comment period. Also attached is a transcript of the
proceedings of. the December 14, 1988 community meeting.
5.0
DECISION SCOPE
As discussed in the Declaration and Site History, the selected
remedial actions that are presented in this decision 'do(.~ent are
desiqned to protect the local drinking water supplies, restore
the .hallow, and deep aquifers to meet MCLs and a 10.' risk level
respectively, control and remediate contamination in subsurface
4
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soils, and prevent vertical migration of contamination in the
aquifers. The difference in decision on cleanup goals for the
shallow and deep aquifers is provided on page 22 of this
documerlt, in section 13 on The Selected Remedies. .
The remedial actions, pumping and treating groundwater and
conduit sealing, will address the area-wide groundwater
contamination. The remedial actions, in-situ soil vapor
extraction, and excavation and treatment will address .aoil
contamination at the Fairchild, Intel, and Raytheon NPL sites and
other areas of soil contamination identified in the MEW Study
Area. .
6~0
DTURE AND EXTENT 'OF CONTAMINATION
Industrial activities. conducted within the MEW Study Area
required the storage,. handling and use of a large number of
',chemicals, particularly solvents and other chemicals used in a
variety of manufacturing processes. Significant quantities of
volatile organic chemicals were used for degreasing, process
operations, and for general maintenance. Raw and waste solvents
and other chemicals were piped and stored in underground systems.
The presence of chemicals in the subsurface soils and .
groundwater, that originated from facilities in the MEW area, are
primarily the result of leaks from these subsurface tanks and.
lines., sumps,. chemical handling. and storage areas, and. utility
corridors. Chemical releases occurred, for the most part, below
the ground surface and migrated downward into the aquifer system.
Investigations at the site have revealed the presence of over 70
compounds in groundwater, surface water, sediments, and .
subsurface soils. The vast majority and quantity of these.
compounds are found in groundwater and subsurface soils. Three
major classes of chemicals were investigated during the RI:(I)
volatile organic compounds, (2) semi-volatile acid and .
base/neutral extractable organic compounds, and (3) priority
pollutant metals. Of these three classes, volatile organics are
the most prevalent. Table 6-1 presents chemicals of concern,
frequency of de~ection, and maximum concentrations.
An extensive area of groundwater contamination has been defined
in the RI and is presented in Figure 6-1. CUrrent site data
indicate that chemicals are present primarily in the A-, B1-,and
B2-aquifer zones. To a much lesser degree, chemicals have been
detected in localized areas of the B3-, C-aquifer, and deeper
aquifer zones. Contamination of the C-aquifer and deeper aquifers
appears to:'ha"ve resulted from chemicals migrating downward from
shallow areas containing eleva~ed chemical concentrations,
through conduit wells, into groundwater of the deep aquifer
system. The~C and Deep aquifers most affected by contamination
..
5
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TABLE 6-1
CHEMICALS OF CONCERN
MIDDLEFIELD/E~S/WHISMAN STUDY AREA
Chemical
Frequency of
Detection.
Geometric Mean
Concentrationb
(mq/1i ter)
, Maximum
Concentrationb
(mq/liter)
Oraanics.,
Chloroform 71/384 0.002 3'.3
1,2-Dichlorobenzene 13/384 0.003 5.2
1,1-Dichloroethane 98/384 0.005 10,.0
1,1-Dichloroethene 153/384 0.006 20.0
1,2-Dichloroethene. 200/384 0.030 330.0
Freon-113 181/384 0~009 46.0
Phenol 21/273 0.002 50.0
Tetrachloroethene 64/384 0.003 3.7
1,1,1-Trichloroethane 184/384 ' 0.017 420.0
Trichloroethene 278/384 0.175 1000.0
Vinyl Chloride 17/384 0.008 25.0
Inoraanics
Antimony 15/205 0.052 0.600
Cadmium 26/205 0.006 0.050
Arsenic 34/292 0.004 0.040
Lead 44/292 0.002 0.043
a/
Values for orqanics are number of detects/number of samples
tor,the fourth round of qroundwater samplihq. Values for
. ~;,'Jorqanics are' the number of detects/number' of well sampled
for dissolved metals.
b/
Values reported are tor all qroundwater samples for each
chemical.
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00.
Legend
Ii TeE ShaJIow Aquifer
Contamill8Uon
. Agriculbnl WeDs Showing
TCE Deep Aquifer Contamination
j\/
c SJuny W8IIs
. FUchIld
m 1nt8t
. Raytheon
.:;~1f
-.J
nil!
01 MEW
Plume
Figure 6-1
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are in the areas of the so-called Rezendes Wells, located near
Fairchild Buildinq 20, and the Silva Well, located at 42 SherI and
Avenue. These wells have subsequently been sealed. The closest
municipal water supply well, Mountain View. '18 (MV 18), is '
located approximately 1800 feet to the southwest of the Silva
Well. Groundwater samples are collected from MV 18 on a reqular
basis. No contaminants have been identified in any water samples
from MV 18. As part of the Remedial Design and Remedial Action
(RD/RA) some additional qroundwater investiqations ~y be
necessary, particularly in the Silva Well area.
Subsurface soil contamination has been found at the Fairchild,
Intel, and RaYtheon facilities, alonq with the facilities of
other PRPs within the RSA. Trichloroethene (TCE), 1,1,1-
trichloroethane (TCA), trichlorotrifluoroethane (Freon-113), 1,1-
dichlaroethene (l,l-DCE), 1,2-dichloroethene (1,2-DCE),'methylene
chloride,' toluene, acetone, and xylene are the chemicals most
commonly detected in subsurface soils in the LSA. Chemicals
associated with activities in the RSA appear to be concentrated
in shallow soils above approximately SO feet or rouqhly extending
to the B1-aquifer. Chemicals are'not found in surface soil
samples. (upper one foot of' soil), and do not appear in soils and
clay of the B-C aquitard. Chemical found in subsurface soil
samples are qenerally similar to those found in adjacent
.qroundwater samples. As' part of the Remedial Design and Remedial
Action some additional soil investiqations may be necessary in
certain areas.
7.0
BASELINE ,SITE RISKS
An Endanqerment Assessment prepared by EPA as part of the RIfFS
was used to evaluate the ramifications of the no-action remedial
alternative and to determine if an actual or threatened release
of a hazardous substance from the site may present an imminent or
substantial endanqerment to public health, welfare, or the '
environment. '
Larqe areas of the site are contaminated. The bulk of the
contamination is present in qroundwater and subsurface soils.
Investiqations at the site have revealed the presence of over 70
compounds. Because of the larqe number of chemicals detected at
the site, a selection process was used to determine the chemicals
of primary concern at the site. The orqanic chemicals that were
selected are: trichloroethylene, 1, 1, 1,-trichloroethane, vinyl
chloride, 1,1-dichloroethane, l-,l-dichloroethylene, 1,2-
dichloroethylene (cis and trans isomers), dichlorobenzene,
chloroform, Freon 113, ~etrachloroethylene, and phenol. Metals
were detected infrequently. OVerall metals are of less concern at
the site that the volatile orqanic chemicals. Several of the
selected contaminants (trichloroethylene, chloroform,
6
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. . ,
dichlorobenzene, tetrachlo~oethylene) have been shown to be
carcinogenic in animals and have been classified by EPA as
possible or probable human carcinogens. Vinyl chloride is a
.human carcinogen. The other contaminants have been shown to
systemic toxicity under certain exposure conditions.
The results of the Endangerment Assessment indicate that exposure
to contaminated groundwater poses the greatest public health
concern. Risks to public health were estimated by combining
information on exposure at possible exposure points with toxic
potency of the groundwater contaminants. Drinking water trom
hypothetical wells to the west ot Whisman Road tor a lifetime
would be associated with an upperbound efcess lifetime cancer
risk of 6(10)-3 (average case) and 2(10)" (maximum case).
Drinking water from a well to the north of the- LSA in the A-
. aquifer would be associated with an upperbound excess litetime
cancer risk of 9 (10)"3 (average case) and 4(10)"2 (maximum case) .
Drinking water from a B1-aquifer well in the same ~rea would pose
an upperbound e~cess litetime cancer risk of 1(10)- (average' .
case) and 5(10)- (maximum case). In addition, estimated intake
of noncarcinogenic compounds from. groundwater at these locations
would: exceed reference dose levels. (RfDs).
known
cause
Contaminants are not present at elevated levels in exposed
surface soils. Consequently, substantial exposure via- direct
contact with contaminated soils or via inhalation of volatile
compounds trom soil or contaminated fugitive dust is considered
unlikely under current land-use conditions. If redevelopment of
the site was to occur for residential or other uses, significant
exposure to contaminants can occur if localized areas of
contamination remained uncovered. Short-term excavation
activities at the site could lead to inhalation of volatile
organic compounds or contaminated fugitive dust, but exposure
would probably be of short duration and frequency, and therefore
. would not pose a significant public health concern.
Low concentration-levels of several chemicals were detected in
Stevens Creek, at the western boundary of the RSA. Any exposure
to these chemicals would probably be of short duration and
frequency, an~ therefore the risk would be negligible.
The Endangerment Assessment also indicates that "environmental"
(flora and fauna) exposure to chemicals from the MEW site is
negligible.
In summary, the results of the baseline risk assessment for the
no-action alternative indicate that exposure to contaminants in
groundwater poses the greatest Dotentia! public health concern.
7,
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3.
8.0
CHANGES TO THE PROPOSED PLAN
1.
The Proposed Plan identifies vapor extraction as the
preferred alternative to address contaminated 80ils.
However, because 80il excavation and treatment by
aeration has been effectively implemented at MEW in ~e
past (at Intel), and other PRPs have expressed interest
in exploring this alternative for their sites, the
selected remedy for soils will also allow soil
excavation to be implemented, provided federal, state,
and local air standards can be met. In addition to
local air standards, Best Demonstrated Available
Technology (BCAT) treatment standards may also be
required depending upon how the excavated soil is
handled. The addition of soil excavation and treatment
by aeration allows flexibility during the RD/RA phases
for other PRPs to use a cost effective alternative for
their particular sites while also protecting human
health and the environment. Soil excavation and
treatment by aeration would most likely be suitable for
small localized areas of contamination.
The Proposed Plan appears to be ambiguous in the
cleanup goal for aquifers within the slurry walls.
While the Proposed Plan cleanup goal for the shallow.
aquifers is 5 ppb for TCE, however, the plan also
states that the shallow aquifer zone is defined as
those shallow aquifers located outside the slurry
walls. ".
2.
Although the aquifers confined by the slurry walls are
disconnected from the outside aquifers (when hydr~ulic
control is maintained by pumping aquifers inside the
slurry walls) a cleanup goal of 5 ppb for TCE (the MCL)
will also be established for aquifers inside the slurry
walls. This goal is more protective of the public
health and" the environment and is consistent with
cleanup goals set by the RWQCB for another site in
Santa Clara Valley.
Identification and sealing of potential conduits was
discussed in text of the Feasibility Study (FS) and in
Appendix L of the FS, but not specifically noted in EPA's
Proposed Plan. Potential conduits will be identified,
evaluated, and sealed if necessary." .
8
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9.0
DESCRIPTION OF ALTERNATIVES
The MEW Feasibility study identified an array of remediation
technologies that were potentially applicable and then screened
those technologies based on their applicability to site
characteristics, compatibility with aite-specific chemicals, and
anticipated performance. Aft~r the technology screening process,
alternat.ives were formulated using combinations of feasible
technologies that are capable of meeting remedial o~jectives.
These alternatives were evaluated based on their public health
and environmental impacts and on order ofaaqnitude cost
considerations.. The short- and long-term effectiveness of each
alternat.ive was also assessed. After this initial screening of
remedial alternatives, a detailed analysis of the selected
alternatives was performed. This section ot the Record of
Decision will present the alternatives evaluated in the detailed
analysis of remedial alternatives. . .
To evaluate the remedial alternatives, the MEW study' Area was
div-ided into five subsurface zones; as show in Fiqure-9-1. The
first subsurface zone (Zone 1, the "cohesive shallow layer")
consists of soil stratum that begins at the ground surface and.
. extends to the water table. The upper foot of the cohesive
shallow layer is not included in the analysis of alternatives
based upo~ the conclusion set forth in the Endangerment
Assessment that there are no health risks' from exposure to
surface soils. The second subsurface zone (Zone 2A, the .
"unsaturated disconnected aquifers") consists of the Unsaturated
zone within the area bounded by the existing slurry walls. ,The
Fairchild slurry walls extend into the A/B aquitard. The Raytheon
slurry wall extends through the A/B and B1/B2 aquitards and into
the B2 aquifer. The third subsurface zone (Zone 2B, the
"saturated disconnected aquifers") consists of the saturated zone
within the slurry walls. The fourth subsurface zone (Zone 3, the
"shallow aquifers") consists of the shallow aquifer system
outside of the slurry walls. The fifth subsurface zone (Zone 4,
the "deep aquifers") consists of the C-aquifer and deeper aquifer
zones. .
The range of potential remedial alternatives are presented for
each subsurface zone: Zone 1 Soils; Zone 3 Shallow Aquifers; Zone
4 Deep Aquifers; and Zones 2A and 2B Slurry Wall System. .
Zone 1 - Soils
No Further Action:
The No Action alternative serves
other alternatives are compared.
would be conducted, and all soil
discontinued.
as a "baseline" against which
For soils, only soil monitoring
pilot study activities would be
9
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SURFACE LAYER
ZONE
I
1 I. '
I I
. --...
, SLURRY WALL
3~ CONFINING. AQUIT ARC
...
ZONE, I
ZONE I
ZONE 2A
ZONE 3
"'!F'
ZONE 3
ZONE 28
SLURRY. WALL
'8-c' AOUITARO
ZONE 4
LEGEND:
~ GROUND WATER LEVEL
r-l, SLURR'r WALL EXTENSION
:..... 'THROUGH AQ'JITARD
ZONE DEFINITIONS:
QONe D COHESIVE SHALLOW L.AYER
(jpNe.w UNS~ iURA T!D OISC"NNEC'TED AQUIFERS
QPNe 2j) SA1"JRA7ED OISCONNECTED
AQUIFERS
,@Ne V SHALL.OW AQUIFERS
(jpNe 4:) OEEP AQUIFERS
SCHEMA TI COF SUBSURFACE
ZONES AT MEW SITE
SLURRY'WALL
MOU N TA I N V:EW, CALI FOR~J I A
PREPARED FOR
REMEDIAL INVESTIGATION/FEASIBILITY STUDY
MIDDLEFIELD-ELLIS-WHISMAN AREA'
Figure 9-1
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In-Situ Vapor Extraction and Treatment:
Soil vapor extraction involves removing the volatile 80il
contaminants without excavating the soil itself. This would be
accomplished by installing vapor extraction wells through which
air containing Volatile Organic Compounds (VOCs) is pumped from
the 80il. Contaminants in tbe extracted air are then removed
using carbon treatment, if necessary, and the. treated air is
released. The treatment process is designed to meet all
applicable air emission 8tandards. .
Partial Excavation and Ambient Temperature Aeration:
This alternative involves excavating and aerating the 80il, which
causes the VOCs to volatilize. Treated soils are then placed back
in their original locations. The areas that would be excavated
are those with the highest level of contamination. Treatment by
ambient temperature aeration would be, conducted inside a
controlled atmosphere enclosure where necessary. This enclosure
would prevent the migration of fugitive.dust and chemicals vapors
from the treatment area. Chemical vapors would be captured by .
activated carbon, if necessary. The primary disadvantages of this
alternative are that soils 'located under buildings and other
structures could not be excavated and treatment of the air
emissions is difficult. .. .
Partial Excavation and Ambient Temperature Aeration with In-Situ
Vapor Extraction:
This alternative involves a combination of the previous two
cleanup alternatives. Excavation and aeration would be used at
those soil contamination zones that are accessible. Vapor
extraction would be used for selected contamination zones that
are not easily accessible, such as soil contamination zones
located under buildings.
Zone 3 - Shallow Aauifers
No Further Action:
The No Action alternative for the shallow aquifers would involve.
only groundwater monitoring: no additional cleanup activities
would be conducted.
Hydraulic Control by Groundwater Extraction and Treatment:
This alternative involves low-rate pumping of the affected
aquifers with monitoring of the plume, and represents the lowest
level of active restoration evaluated for the shallow groundwater
system. Recovery wells would be installed in appropriate
locations along the periphery of the plume. The extraction well
10
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would operate at a pumping rate sufficient to insure that the
plume would not expand laterally. Extracted groundwater would be
treated using air stripper-based treatment systems and vapor-
phase carbon adsorption (where necessary) which would be operated
under applicable air and water quality requirements. The treated
water would be discbarqed to stevens Creek via the storm sewer
system. A network o~ monitoring wells would be used to determine
any changes in the extent of the plume.
Hydraulic Remediation by Groundwater Extraction and Treatment:
This alternative involves pumping the affected aquifers at a rate
sufficient to achieve an accelerated reduction in the extent of
the plume and reduction of chemical concentrations in the
groundwater. This a1ternative would. also utilize a network of
monitoring wells to verify remediation progress. Extraction wells
would be installed in locations around the periphery and in the
plume~ Extracted groundwater would be treated using air stripper-
based treatment systems and vapor-phase carbon adsorption if
necessary, which would be operated to meet applicable air
emission limitations. Treated water would be discharged to
stevens Creek via 1:he storm sewer', system.
Vertical Impermeable Barriers:
This alternative iuvolves constructing a vertical impermeable
barrier around the entire MEW plume, in order to hydraulically
isolate the shallow aquifers. This alternative would not result
in a permanent reduction of chemicals currently in the shallow
aquifer system, unless, implemented in conjunction with other
remedial alternatives.
Zone 4 - Deep Aauifers
No Further Action:
The No Action alternative, which is used as a baseline for
evaluation of remedial alternatives, consists of monitoring the
existing groundwater plume.
Hydraulic Remediation by Groundwater Extraction and Treatment:
Elements of this alternative are described above for shallow
aquifers and are essentially the same for the deep aquifers.
Zone 2A - Unsaturat~ Disconnected Aauifers (Slurrv Wall Svstem)
No Further Action:
The No Action alternative involves no further treatment of Zone
2A soils, located within the area bounded by the existing slurry
walls. Under this a1ter.native, the unsaturated disconnected
11
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aquifer soils would remain contained laterally by the slurry
cutotf walls. Long-term monitoring of water levels and chemical
concentrations in the saturated disconnected aquifers (Zone 2B)
and the shallow aquiter (Zone 3) water-bearing zones outside
(beneath and around) the slurry walls would be required to detect
migration of chemicals trom the unsaturated soils within the
slurry walls. .
In-Situ Vapor Extraction:
This alternative for remediation of the unsaturated disconnected
aquifer soils involves aerating the Zone 2A soils by vacuum
extraction, treating the extracted air in accordance with
applicable air quality requirements. Extracted volatiles would
pass through an emission control system consisting of vapor-phase
carbon adsorption for removal of the VOCs from the extracted air
prior to discharge to the atmosphere in accordance with
appropriate air requirements. This alternative would also use.
existing extracti~n.wells to remove the groundwater necessary to .
maintain desired water levels. The extracted groundwater would be
treated using air strippers or carbon adsorption. to remove VOC '.5
prior to discharge of the extracted groundw~ter to Stevens Creek.
Maintain Inward and Upward Gradients:
This alternative involves pumping limited quantities of .
groundwater from the saturated portions. ot the aquifers within
the slurry walls. This process will maintain a hydraulic gradient
inward across the slurry walls and upward, thereby restricting.
the movement of chemicals outward into. the shallow aquifer zone.
(Zone 3). The use of hydraulic control in conjunction with the
slurry walls ensures that contaminates will be kept localized
(within the confines of each slurry wall) and add an additional.
level of protection if a slurry wall failure was to-occur. The
conjunctive use of slurry walls and hydraulic control is referred
to as a slurry wall system. The extracted groundwater would be
treated using air stripping or carbon-adsorption prior to
discharge to Stevens Creek. .
Flushing:
This alternative, for remediation of unsaturated aquifers within
the slurry walls (Zone 2A), involves the extraction of water from
the saturated soils, re-saturation of the unsaturated soils,
treatment of extracted groundwater by air stripping, and
reinjection of the treated water into resaturated soils within
the slurry walls. The unsaturated soils woul~ ~e remediated by"
flushing using a network of water injection and extraction wells. .
Extracted groundwater would be treated by air stripping prior to
reinjection through the injection well network. .
12
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. .
Partial Excavation and: Ambient Temperature Aeration: .
This alternative tor 2A soils involves the partial excavation of
highly localized areas ot chemicals containing unsaturated'
disconnected aquifer soils. Treatment by ambient temperature
aeration would be conducted inside a. controlled atmosphere
enclosure where necessary. This enclosure would prevent the
migration of fugitive dust.and chemicals vapors from the
treatment area. Chemical vapors would be captured by activated
carbon, it necessary. .
...
Zone 2B - Saturated Disconnected A~ifers (Slurrv Wall System)
, No Further Action:
The No' Action alternative involves no further'treatment of the
contained soils or hydraulic gradient control within the area
bounded by the slurry walls. Long-term monitoring of water levels
and chemical concentrations in the saturated disconnected
aquifers (Zone 2B)and. the shallow aquifer (Zone 3) water-bearing
zones: outside (beneath and around) the slurry walls would' be
required to detect migration of chemicals trom the unsaturated
soils within the slurry walls.
In-situ Vapor Extraction With Dewatering:
This alternative for remediation of saturated aquifer soils
involves dewatering the aquifers within the area bounded by the
slurry walls, aerating the dewatered soil pore spaces by vacuum
extraction, treating the extracted' air; it required, with vapor-
phase carbon adsorption, treating the extracted groundwater with
air stripping, and discharging the treated air and water in
accordance with applicable air and water quality requirements.
The extracted groundwater would be treated using air strippers or
carbon adsorption to remove VOCs prior to discharge of the .
extracted groundwater to Stevens Creek. .
Maintain Inward and Upward Hydraulic Gradients:
This hydraulic control alternative for saturated aquifers within
the slurry walls (Zone 2B), involves pumping relatively small
quantities of water from within the slurry wall areas for the
purpose of lowering the interior water table to produce inward.
and upward hydraulic gradients. The inward and upward hydraulic
gradients would preclude the outward migration of chemicals
present with the zone contained by the slurry wall areas. The
small quantities of groundwater pumped trom within the slurry
w~lls would be treated using on-site air stripper-based systems
or carbon adsorpt~on, which would be operated in accordance with
applicable air and water quality requirements. The required
monitoring for this alternative would be the same scope as that
13
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required under the "No Further Action" (monitoring only)
alternative.
Flushing:
This alternative for remediation of saturated aquifers within the
slurry wall areas involves the extraction of water from the
saturated soils, treatment of extracted groundwater by air
stripping, and reinjection o~ the treated water into saturated
soils within the slurry walls. Extracted groundwater would be
treated using air strippers or carbon adsorption prior to .
reinjection through the injection well network.
10.0 APPLICABLE OR RELEVANT AND APPROPRIATE REOUIREMENTS (ARARs)
Under Section 121(d) of CERCLA, as amended by SARA,. the selected
remedy must achieve a level or standard of cleanup that assures
protection of human health and the environment. In addition,
CERCLA requires. that remedial actions achieve a level. or standard
of cleanup that meets legally applicable or relevant and
appropriate requirements, standards, criteria or limitations
(ARARs) . . .
ARABs associated. with the site have been generally separated into
three categories: (1) ambient or chemical specific requirements.
that set health or risk-based concentration limits or ranges. for
particular chemicals; (2) performance, design, or action-specific
requirements' that govern particular activities; and (3) location-
spec;fic requirements. For this site the selection of ARARs is
dependant on the defined beneficial use of groundwater as a
source of drinking water.
Beneficial Use of Local Groundwater as a Source ~f Drinkinq Water
The requlatory framework associated with the cleanup of
groundwater and soil at the site is driven by the beneficial
(current or potential) use of local groundwater. As stated in 40
CFR 300 of the Federal Register on page 51433 (December 21,
1988), "The goal of EPA's Superfund approach is to return usable
ground waters to their beneficial uses within a timeframe that is
reasonable". Drinking water is considered to be the highest
beneficial use and affords the greatest level of protection and
cleanup. .
As required' by the California Portor-Cologne Water Quality
Control Act, the Regional Water Quality Control Board -San
Francisco Bay Region defines the beneficial uses of various water
bodies in the greater San Francisco Bay Area. Water bodies and
their beneficial uses are presented in The San Francisco Basin
Plan. This regional plan has been promulgated and is an ARAR for
14
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this site. In the Basin Plan the Regional Board classifies the
shallow aquifers in the area of the MEW plume as a "potentially
suitable for municipal or domestic water supply". In addition,
the Basin Plan states that the "use of waters in the vicinity
represent the best information on beneficial uses". currently,
the C and Deep aquifers at the site are used as a municipal
drinking water supply.. . .
CBEHXCAL-SPECXFXCARARS
Chemical-spec~fic ARARs for the MEW site are Federal and state of
California drinking. water standards. Each is relevant and
appropriate to set cleanup standards at the site. A list of .
Federal and state drinking water standards are presented in Table
10-1.. .
Federal Drinkina Water- Standards.
Potential drinking water standards at the site include Maximum
Contaminant Level Goals (MCLGs) and Maximum contaminant Levels
(MCLs) :
As stated in CERCLA section 121 (d) (1), MCLGs are mentioned as
potential cleanup standards when these levels "are relevant and
appropriate under the circumstances". After weighing all factors,
EPA has determined that they are not relevant and appropriate for
the site.
The relevant and appropriate standards to establish groundwater
cleanup levels at the site are the Federal Maximum contaminant
o Levels CHCLs), as presented un4er Safe Drinking Water Act. EPA
bases this decision on the fact that MCLs are fully protective of
human health and, for carcinogens, fall within the established
acceptable risk range of 10.10 to 10.7. MCLs are ARARs for
groundwater at the site and are also used to establish soil
cleanup levels. 0
State Drinkina Water Standards
California Drinking Water Standards establish enforceable limits
for substances that may affect health or aesthetic qualities of
water and apply to water delivered to customers. The state's
Primary Standards are based on federal National Interim Primary
Drinking Water Regulations. currently, California has promulgated
MCLs for cadmium, arsenic and lead, and some of the organics of
concern.
.0
15
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TABLE 10-1
FEDERAL AND STATE GROUNDWATER STANDARDS
.MIDDLEFIELD/ELLIS/WHISMAN STUDY AREA
Chemical
Federal
Maximum Contaminant
. Levels CHCLs)
(mg/liter)
State
MCLs
(mg/li ter)
oraanics
Chloroform 0.100 -
1,2-Dichlorobenzene
1,1-Dichloroethane
1,1-Dich~oroethene 0.007 0.006
1,2-Dichloroethene
Freon-113
Phenol
Tetrachloroethene
1, 1, 1-Trichloroethane 0.200 0.200
Trichloroethene 0.005 0.005
Vinyl Chloride 0.002 0.0005
Inoraanics
Antimony
Cadmium 0.01.0 0.010
Arsenic 0.050 0.050
Lead 0.050 0.050
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ACTIO. 8PBCI7IC ARAB.
Groundwater extraction and treatment involves pumping, treating,
and discharging the treated groundwater and/or reinjecting it
into the aquifer. Soil remediation can include excavation and/or
in-situ treatment. With groundwater treatment and in-situ vapor
extraction, Volatile Organic Chemicals (VOCs) would be removed by
. air stripping and/or Granular Activated Carbon (GAC) adsorption.
Air stripping requires consideration of ARARs for VOC emissions,
GAC use requires consideration of ARARs associated with carbon
regeneration or disposal, and discharge or reinjection must mee~
. specific ARARs.
Discharae to Surface Water
Substantive National Pollutant Discharge' Elimination System
(NPDES) permit requirements would apply to treated effluent ..
discharging to surface waters. These would primarily be effluent
limitations and monitoring requirements. The RWQCB regulates
NPDES discharges.. Ambient Water Quality Criteria are used by the
State of California to set Water Quality Standards in the San
. Francisco Bay Regional Basin Plan. Standards in the Basin Plan
are used by the RWQCB to set NPDES effluent discharge
limitations.
section 402 of the Clean Water Act., as. amended in 1987, will
result in the prohibition of discharge of non-storm waters to the
City of Mountain View storm sewer system by 1991.
Reiniection of Treated Effluent Into Aauifers
If treated groundwater is reinjected, regulations governing
underground injection may apply. Specifically, the Federal Safe
Drinking Water Act requires an Underground Injection Control
(UIC) program. In California, the UIC program is administered by
U.S. EPA. TheUIC program prohibits treated effluent from being
injected, into or above a source of drinking water. Except when
it is pursuant to a CERCLA cleanup UIC regulations do not
regulate the concentration of constituents, rather they regulate
only the method and location of the injection. These Federal
requirements regarding injection may be -relevant and
appropriate- to the site.
Pederal RCRA requirements and the State is Toxic Injection Well
Control Act of 1985 (Cal. Health' Safety Code Section 25159.10
At~) might also be -relevant and appropriate- to the
reinjection of treated groundwater.
16
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Discharae to Sanita~ Sewers
Discharge of treated groundwater to the local sanitary .ewer
system requires compliance with the City's of Mountain View's
Industrial Waste Ordinance and the Clean Water Act Pretreatment
Standards. The City's Ordinance sets forth effluent quantity and
discharge concentration limits, along with standards for
monitoring and reporting. Substantive. requirements are "legally
applicable" for on-site discharges of the treated,. water. The
Clean Water Act allows municipalities to determine pretreatment
standards for discharges to Publicly OWned.Treatment Works
(POTWs), within its jurisdiction. .
Air StriQpina - Air Emission Standards
Any new source that emits toxic chemicals to the atmosphere at
levels determined by the San Francisco Bay Area Air. Quality
Management District (BAAQMD) "to be appropriate for review" must.
have authorization to construct 'and operate. Although on-site
treatment facilities are exempted by CERCLA from the .
administrative requirements of the permit, emission limits and
monitoring requirements imposed by the BAAQMD permit must be met.
Carbon Adsorption
. Use of granular activated carbon (GAC) for remediation of VOCs
can trigger requirements associated ~ith regeneration or disposal
of the spent carbon. If the spent carbon is a listed waste or a .
characteristic waste then it is regulated as a hazardous waste
under RCRA and California's hazardous waste control laws.
Disposal of contaminants can trigger RCRA land disposal
restrictions. For disposal, the spent carbon would need to be
treated to meet Best Demonstrated Available Technology (BCAT)
treatment standards, and RCRA off-site Subtitle C disposal
restrictions would also apply. .
Regeneration of activated carbon, using a high-temperature
thermal process, is considered "recycling" under both Federal and
Califorf1ia hazardous waste regulations. Transportation, storage,
and generation of hazardous waste for recycling must comply with
requirements in RCRA and California hazardous waste control
regulations. Performance standards for hazardous waste
incinerators can also be requirements for on-site carbon
reactivation. On~site storage of contaminated carbon may trigger
substantive requirements under municipal or county hazardous.
materials ordinances. If the spent carbon is a hazardous waste,
construction and'monitoring requirements for storage facilities
may also apply.
17
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Excavation. Above-Ground Treatment and Disposal of Soil
Excavated contaminated soils will require on-site treatment or
disposal off-site. On-site treatment by above-ground soil
aeration, will need to comply with the substantive provisions of
the BAAQMD and possibly RCRA land disposal restrictions.
Excavated soil classified as a hazardous waste can also trigger
RCRA, state and local requirements. EPA land disposal
restrictions may be applicable for off-site disposal. RCRA
Subtitle C may apply to disposal of soils on-site.
For the on-site treatment of soils, the BAAQMD regulates aeration
of soil containing over 50 ppb of organics. The BAAQMD sets rates
at which soil can be aerated depending upon the level of
chemicals. BAAQMD Regulation 8, Rule 40 on the treatment of soil,
assuming it is a hazardous waste, may also trigger RCRA land
disposal restrictions and BOAT treatment requirements.
LOCATION SPECIFIC ARARs
Fault Zone
The MEW sites are not located within 61 meters (200 feet) of a
fault. Therefore, the fault zone requirement of 40 CFR Part 264
is satisfied.
Floodplain
A hazardous waste treatment facility located in a 100-year
floodplain must be designed, constructed, operated, and
maintained to prevent washout of any hazardous waste by a 100-
year flood. The MEW site is not located in a floodplain,
therefore these requirements are neither applicable or relevant
and appropriate.
11.0 OTHER CRITERIA CONSIDERED
In establishing selected remedial alternatives, EPA considers
various procedures, criteria and resolutions. These "to be
considered11 criteria (TBCs) do not raise to the level of ARARs,
but are relevant to the cleanup of the site. The following
discussion presents selected criteria relevant to the selection
of remedial alternatives.
18
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Criteria Establishina Local
Water
Various criteria were used to establish that the shallow, C, and
Deep aquifers are a source of drinking water. EPA's groundwater
classification system was used. Using the "EPA Guidelines for.
.Ground-Water Classification" as a quide, EPA determined that the
A- and a-aquifers in the MEW" area are classified as "potential
drinking water sources". currently, the c-aquifer and Deep'
aquifers are used for drinking water and therefore would be
classified as a current drinking water source. As stated in the
ARARs section, the Regional Water Quality Control Board.
classified the shallow groundwater as "potentially suitable. for
municipal or domestic water supply". The RWgCB determined that
this classification is consistent with the state Water Resource
Control Board's Resolution No. 88.-63, which describes criteria
for designating sources of drinking water.
Groundwater as a
Source of Drinkina
state Criteria for Groundwater CleanuD
Califorriia has criteria for evaluating drinking water quality and
groundwater cleanup: advisory Drinking Water Action Levels, and
advisory Applied Action Levels.
Drinking Water Action Levels are health-based concentration
limits set by DHS to limit public exposure to substances not yet.
requlated by promulgated standards. They are advisory standards
that would apply at the tap for public water supplies, and do not
rise to the level of ARARs. Nonetheless, they have been.
considex'ed in developing cleanup standards for the MEW site.
Applied Action Levels' (AALs) were developed by DHS for use with
the California Site Mitigation Decision Tree. AALs are quidelines
that DHS uses to evaluate the risk a site poses to certain
bioloqic receptors. They are neither enforceable, nor ARARs, but
have been considered in d.veloping cleanup standards for the MEW
site.
Groundwater criteria, to be considered for determining cleanup
levels, are presented in Table 11-1.
California Resolution 68-16
Resolution 68-16 is California's "statement of Policy With
Respect to Maintaining High Quality of Waters in California". EPA
regards Resolution 68-16 as criteria to establish groundwater
cleanup levels. The poliCl~'~equires maintenance of existing water
quality unless it is demonstrated that a change will benefit the
people of the state, will not unreasonably affect beneficial uses
of the water, and will not result in water quality less than
prescribed by other state policies.
19
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TABLE 11-1
GROUNDWATER CRITERIA TO BE CONSIDERED
MIDDLEFIELD/ELLIS/WHISMAN STUDY AREA
Chemical
state
Drinkinq Water
'Action Levels
(mq/liter)
State
Applied
Action Levels.
(mg/liter)
Or9anics
Chloroform
l,2-Dichlorobenzene
1,1-Dichloroethane
0.020
0.130
0.006
0.020
1,l-Dichloroethene
1,2-Dichloroethene-
0.016
Freon-113
18.000
Phenol'
Tetrachloroethene
0.004
l,l,l-Trichloroethane
Trichloroethene
Vinyl Chloride
Inoraanics
Antimony
Cadmium
Arsenic
Lead
a/
Applied Action Level for water for human receptors.
-------
A beneficial use of the groundwater in the shallow and deep
aquifer system is drinking water. Establishing a cleanup level
which maintains this beneficial use should attain the
. requirements of Resolution. 68-16.
Remediation Levels for Soils
A standard for the remediation of contaminated soils was reached
during the Feasibility Study by using a simple percolation-
transport model with the concepts presented in California's Site
Mitigation Decision Tree. The model was used to determine
concentrations in soil based upon transport aownward into
groundwater. Based upon the analysis from the model, a soil
remediation goal of 100 times the groundwater remediation level
is appropriate to set cleanup standards in soil.
Health Advisories
EPA considers that for a remedial action of a drinking water
source to be protective, it. should have a cumulative risk that
falls within a range of 10.4 to 10.7 individual lifetime excess
cancer risk. To evaluate the risk to public healthp~sed by
recommended cleanup qoals, health advisories were used to
establish cumulative risk. Lifetime averaqe daily doses (LADD)
were calculated by mUltiplying a concentration by 2 liters per
day and dividinq by 70 kiloqrams. Cancer risk for a constituent
of a given concentration was .determined by multiplying the LADD
by its Cancer Potency Factor (CPF). Ratios of contaminants in
aquifers of the site were then calculated in relation to TCE. A
summation of risk for carcinogens in each aquifer were calculated
for a given concentration of TCE. For a 5 ppb (MCL) .cleanup goal.
for TCE in the A-, B1-, and B2- aquifers the cumulative estimated
carcinogenic risk falls within a ranqe of 1. 3 (10) -5 to 7.4 (10) -5.
In the C- and Deep aquifers the cleanup goal of 0.8 ppb
corresponds to a cumulative estimated carcinogenic risk of .
1.0(10)-6. Supporting calculations are presented in the
Feasibility Study.
Cleanup goals in the shallow aquifers, above the B/C aquitard,
are set at 5 ppb for TCE. Cleanup goals in the C and Deep
aquifers, below the B/C aquitard, are set at 0.8 ppb for TCE.
Assuming the ratios of carcinogen remain relatively constant,
attainment of these goals will result in achieving EPA's
acceptable risk range of 10-4 to 10-7 upon completion of the
remedial action. .
Air Strippinq Control policies
Any existing and new source(s) that emit toxic chemicals will
have to comply with any EPA, BAAQMD, or Air Resources Board
policies on control of air emissions from air-strippers.
20
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12.0 :2UMMARY OF ALTERNATIVES ANALYSIS
This section presents an analyses of the alternatives, evaluated
in the detailed analysis of remedial alternatives, with respect
EPA's evaluation criteria. Design elements of the alternatives
are presented in Section 9.0. Table 12-1 provides a summary of
the advantages and disadvant:ages of each alternative's
performance and cost.
State and community acceptance are discussed below:
State Accectance
The State (of california) generally,supports EPA's proposed
cleanup plan. The state commented, however, that the cleanup
goals for soils and groundwater inside the boundary of the
existing slurry walls should be 0.5 ppm.TCE for soil and 5 ppb
TCE for the groundwater; the same goals as for outside of the
slurry walls. .
In the Responsiveness summary, EPA stated that the slurry walls.
in conjunction with pumping and monitoring will be protective of
the public health and the environment, with the 1 ppm TCE cleanup
goal for soils bounded by the slurry walls. This monitoring and
pumping strategy will limit the amount of contamination that can
leach into the shallow aquifers, outside of the slurry walls. EPA
did respond to the State's request of a 5 ppb TCE cleanup goal
tor all shallow aquifers, by establishing the 5 ppb TCE cleanup
goal for the aquifers inside of the slurry walls.
Community Accectance
The community agrees with EPA's proposed remedial alternatives,
although there is concern with the length of time estimated to
achieve the shallow aquifer cleanup goals. The use of the "hazard
index" 1ias urged to establish cleanup goals instead of MCLs. EPA
explained in the Responsiveness Summary that the hazard index was
not applicable to the MEW area.
In addition, reuse of the extracted groundwater was recommended
by the community. As stated in the Responsiveness Summary, reuse
of extracted groundwater will be evaluated and is a component of
the ROD.. .
The Responsiveness Summary (attached) addresses these concerns
and others in more detail.
21
-------
Tabln2-1
Crltarla 'or tha Evaluation o' Remedial AUernallv..
(continued)
lOHG -1(111 Aml'l ANNUAl PRE UNI
lONG. URH 'ROIEU 1018 Of (ApnAl 0 a N WRIH
SHORI-IUlN (fFEtllV£NESS REDUCES lOIICI". C(ltPlIAN(( tIUIWI HEAlIH AND (0515 COSIS .round,d,
ALlERNAfiVE W(IIVEtUSS NeD PUUWUNU ~Blllf'. VOl~( IHPl(HEnfADILlf' IIITH WAs 1"( (nVIRONHun 'CCO'S. 'OOO'S. ooo'sa
lONE 28
NO fURIHER Atlll11 NO EffEtI IN AllOYS tllll'O NO Atilt( RUM- tIO 1((....Ul DOES 1101 PROIEttlOll U 160 1,600
SHORI-UIII NIGRAI ION liON IN 1011(11'. lIMIIAIIONS MU I All PROVIDED BY
HOBILII' OR'VOLUM( AWs IIOHIIOIING CltU
IN-SIIU SOil AERAIION (fFEClIVE IN 'EIltlANEN' REOUCES 10 lit I", 110 UtHNltAl COfU'llU 'RO'IOU '.:61 I.:" '.AOO
~JlH CARP SHORI- tEIII SOlUIION . H081l1l' AND lIMnAIIOHS tilTH ARARs 'ROIECIIOI8
SORPtiON AND VOLtitE 2.091 I. 76J 9,-
REGENERAIION)
HAINIAIN IWARD All) EHEnlVE IN 'EAtWfENI REOUtES 1011(11', NO nt..ltAL tOMPLUS. PROVIDES 0 595 6,000
UPWARD H'BRAULlt SHOAl -1(111 SOlUIION BUI tlJBILIfY AND . lIHIIAIIONS tilTH WRs PROUt 11018; .
GRADUNIS AwnH REQUIRES VOLUHE IIUDS
IRUIHENI f CDHIINUED INSlltUTlOIW.
U'RACtEO IIAtER) Nt,. NG CDHIROL
flUSHING .II..H 1101 EHEtIlI( 'ERHAMEN' .RLOUCES 'OIICII'. NO' FEASIBLE DUE tOfU'LIU PlOtEtIlOl8. 1,1)) 1,459 IJ, 000
IRUIHENI Of IN SHOll - 1£111 SOlUIION IF filSll..' AND 10 COltPLU SIIE tlnH ARARs lIMIJED. BY
EXIRAe'EO tlA'ER) 110 [HEMltAl VOlUME I F NO SIRAIIGRAPH' tHENICAl
MIGRAIION tHEMICAL MIGRAIION " IGRA I 1011
-------
Table 12-1
Criteria 'or tha Evaluation 0' Ramedlal Alternatlv..
.contlnued' lOHG-1(1IIt MIOl'l AltNUAl I'RE5(NI
lONG- Ulllt I'ROTEUIOII OF tAPI1Al 0 I M WORIH
SII)II- IEAII (ffEt II VENESS REDUCES 10Xlt11Y. tOftPllANtE HUHAH HEAL IN All) (0515 (OS IS (rounded,
Al URNAIIVE (ffEUIVENESS AND PERMANENCE tiOBIL 111. VOL litE INPUNENIABllny WnN ARARI IHE EIIVIIIOItIE.I '000'51 1000'SI 000' II
lONE ZA
NO fURIHER ACT 1011 NO (ffEtT 1M AllOWS NO AUIVE AEOUtllOll NOUtHNltAL ooES NOI PROUtllOll II/A MIA MIA
SOOR I - 1£ All tOllllNUED IN 101ltl1', lIMItAlIONS MEEI ALL PRO'ID£D BY
MIGRAIION MBllIIY OR 'QlH, ARARs IIJH 1101 IHG DIll'
IN-SIIU SOIL AERAIIOII (ffEtllV( IN 'EAlIAIUNI REDUCES 101ltllY, NOUtHNltAL tOftI'll U 'ROVIOU ZOJ 618 1,800
l"IIH CARBON SIIORI - URN SOlUIION MBllIIY AND llMIIAIIOIIS "IIH ARARs PROUtllOll
DSORPIION AND VOLUME
REGENERAIION,
KAINIAIN INWARD AND (ffEtllVE IN 'EIIIW!ENI REDUCES 1011t11Y. 110 Utl.ntAL tOttPlI U PROVIDES 0 405 4,100
UPWARD HYDRAULlt SOORI - UAII SOlUIION BUI II»BIl If' AND LIMitATIONS "ITHAlARs 'ROUUI";
GRADIENTS ."ItH A~UIRES VOLUHE 11((05
IRUI"E.1 Of t IINUED INSllTUIIONAl
EXlRAtlED "AIEA' PIIIPIIIG (0111 ROtS
flUSHING ."IIH NOI (ffUTlVE 'EIIIW!EIII REOUtES lOlltllt. NOI fEASIBLE DUE tOttPlI ES 'ROUtt I" 884 8" J,5oo
lREAIMElI1 Of III SHORI - UIIIt SOlUIION If . MBUIT' AND 'Ol"'£ 10 (OftPlU SIU "11" ARAAs LIMITED BY
EXlRAtlED "AIEA) NO tHEMltAl IF NO (HENltAl SIRATIGRAPHY tHEMltAL
MIGRAtiON ""RA 11 ON MIGRAII..
PARIIAl EltAVAl1011 (ff(tIlVE, BUr ftlllW!ENI REDUCES 1011(11'. Dlffl(Ulf 10 tOftPLIU PROVIDES 869 0 900
"11" _1£111 PO((NIIAl fOR DlUIIOH 11»8 UIT' AND (OIIIROl AlA "11" ARAKs PROUUIOII
IEMPERAIURE AERAIION IHCREASED EIPOSURE VOL UHE E"'I 55 10115
1"11" tARBON DURING EltAVAllON
DSORPIION AND
REGEHERAIION,
-------
ALlEAHAtl¥E
lONE.
NO fURIHER ACIION
HYDRAULIC REMEDIAIION
BY GROUND IIAUR
UlRACtlOH AKD
IREAIMENI
(I) M/A . NOI APPL'CABlE
SHOA'.'ERIt
(ff(CtIVENU$
NO (fUU I.
SHOIII. UIUI
(fUClln I.
SHOll.. UAH
Table 12-1
Criteria 'or Ihe Evaluation 0' Re~edlal Allernatlvea
(continued)
lOHG. UR"
EffEUIVEMUS
AM) PEAttANEHC(
REDUCES 'OIICII'.
HOBILltY. lOLUNE
IHPUMElnA81l11Y
COMPLIANCE
WIIH MARs
lONG- 111M
PROI(UIOI8 Of
tIUHAN HEAL I" All)
'H( (NVIRONH£NI
AllOWS NO ACIIVE REDUCIION NO UtlltlCAl DOn NOI PAonclION
CONIINUED 'N 101 Itl IY . LIMitAtiONS "(( I AU PROVIDED BY
MIGRAtiON HOBll..Y OR 'OlUHI ARARs .O..IORIHG ONLY
PUMMENI REDUCES lOllCII" 110 UCHNICAl C(JtPlIES JROVIDU
SOLUI.ON HOB Illt Y AND lIHItAflONS 1111" ARARs RonclIOH
VOLUHE
aOOl'l ~JNUAl PRESENt
(APlfAl 0 I" IIORIH
CDS'S CDS'S (rounded.
1000'51 1000'51 OOO'si
.81
181
',000
1)9
449
. fAGO
4;200
-------
Table 12-1
Criteria for the EvaluaUon o' Remedial AU.naUv..
lconllnued'
lONG. II'" 'UD"l ANNUAl 'RI$I"'
lONG- URN 'RO.[(IIOII Of CA'UAl 0 a N IIOR'"
SHOll. . lUll UnCIIV(HUS RlDUtIS 1011(1". COtIPl,ANt( IIUIWI HIAlIH AND (OSIS tos.s ,roundld,
ALnRHAIl1( Iff([IIUNUS AND 'IRHAHUIU MOBllllla .DtUN( l",lIMNIAlllIIr MUN AWl JNI IN'IIIOIII:NI 1000'11 1000'51 OOO'sl
IUt( J
II) fUl'"11 At 11011 110 £Inn II AllOWS NO le.I.1 I(DUCIIOII 110 UtlffltAl DOn 1101 PIIOIIUIIII 110 585 ',200
Sldl UAII CONI,IIUEO II 10liel If. lINIIAIIONS Mn I All 'Ro'IDIO I'
II I IiRAI1111 ...U." .. ,.. III MAls 1018101.. .,
"iDRAUl.C CONIROl II UUU'I( III .INlAIIIII R(OUtIS 101It.II. 110 UCIIN.Ul tONPt IU 'AI II AI. , . 'OJ . .Il' ",500
'IUD IIAUI SltOlf. fiRM 50lUII0II 101 t«J81U "AND lINIIAIIONS IlIIN ARARI fIOIIUIe.; ..nos
IIIRAtllOtt ':JIUIRU 'DUll INSI IIUIIOIW.
AND ..aIAIH1ln t II"U(O tOIUROlS
.IIIPING
"iDiAUlIC 11"(01111011 untlln II 'UlHANUn R(DUCIS 101Itll'. 110 UtHNltAl (_UU .80llDU 1,5" 2,501 n ,goo
II 1i10UND IIAUI SOOfU. 1£111 SOI.UIIOII tlDPlun AHD ll"IIAIIONS 1111" Wls .80.U1I0I
IIIAt 11011 AlII . 'DUIII 31. GOO
18(AI"(l1I
'l.f'tAl '",(AII(ABLE (fUUnE. BUI 10f A Doei NOT .IIUSIBU IJU( IIJU IOf 'AI II Al U.4'" 35.400
BARRURS 1'OIIIIIAl 101 ~IIHAN(ln . .MEET CRITERIA t 10 UtHN.tAl HU' All '1011[1101; .IIOS
lll'OSURI OURING LUIIOII .ll"' fAf IONS AWs .NSIIIUIIONAl
(IIISIRUC IIUt (0111 ROl 5
1 .
Note: Section 121(b) 01 CERCLA slates a prelerence lor Irealment which permanenlly and
. slgnlflcanlly reduces the volume, toxicity or mobility ollhe contamlnanls. The use 01 vertical
Impermeable barrters (I.e., slurry walls) by themselves Is containment and source conlrol, and
does not conslilule treatment. Only with the addition 01 groundwater exlractlon and treat~nt
does this alternallve meel slatutory criterta. While Ihls evaluation differs somewhat from the
evaluation found In the FS, II does 001 allect EPA's remedy selection.
-------
Tab.. _-1
Criteria lor the Evaluation 01 Remedial Altern.tlvea
lOHG-IERII AOOI'l ANNUAL 'RESENI
lONG- UR" 'ROIEUION Of tA'IIAL 0 a.. IIORIN
SHOll' - 'UII EUIU IVENESS REOU(ES 101ICII.. (OM'L IAN(( HUMAN NEALIHAND (0515 (051 (rounded.
AL IERNA' IV[ (fun I VENESS AHDPIRNAHENC( trJ81l1l.. VOLUHI IHPUtll'nABlqn IIIIH ARARI IHE INVIROHHINf 'OOO'SI '000'51 000' II
lone I
NO FUR'HER AUION NO (fUn II AllOWS NO AClIV( REOUt- NO UC..IUl DOES NO' 'ROUCHOIt I/A(I) H/A N/A
SIIJR' . UAII CONfiNUED flUN II 1011UIY. . lllli 'AI IONS . MEU All PROVIDID B'
"IGRAHOM 1I08Ill" OR 'OLUM( ARARs OIlOR I NG ONLY
IN.SIIU SOIL AERAIIOM (fU(flV( II 'ERIIAIIEI' REDUCES 101ICII,. II) J(C"IUl (ooiIES PRO'IOIS I fAOl 8U 1,8~
JIIiIN URION SHORI - UAII SOL Ufl ON IIOBILI I' AND llMI lA' IONS IIIIH ARARI PROUC I ION 10 . 10
DSOR'flON AND VOlUHI 1,251 861 5,000
REGINIRAflON'
PAR'IAl IICA.AtION UnCIII(, BUI p(IIMlnl' BU' REDUCES 'OIICI", Dlff ICUl 1 10 DOES NOr CHEIIICAlS un 6.61J 6.100
InlH AMlU.I POlllt IAl '01 MOl A COHPUII 1108 Ill" AND CONIROl All "Elf ARARs II SOILS C:OUlD
IIM'ERAIURE AIRAIION INCREASED SOlut ION 'OlUHI EHISSIONS AHQ ,U fOR UlfU- III GRAtE 10
1"I1H CARBON. UPOSURE DURING IHPA(f(DSOIlI tAVAIED SHAllOW
DSORPJION AND UCA'AIION NOI REH(lUAfI SOILS AQUIFERS
RIGINERAIIOM)
,ARIIAl EICA.AIION UFECHVI, BUf 'ERIIAIIINf . - .EDUCES 101lC I", DlffiCUl' fO COMPLIES ,ROVIDES ',:25 218 ',~OO
IIIIN NlBUNI POUNflAl fOR SOlUt ION 1IJ81L II. AND (oNIROl AIR I1I1N AIARI 'ROUC HOlt to
tEMPERAtURE AERAIION INCREASES . vblUHI . IMISSIONS. 1,151 281 8.600
AND IN-SIIU SOil UPOSURI DURI..
AERAIION UUVAIION
11111N CARBON
DSORPIION AND
REGENERAIION'
-------
13.0 THE SELECTED
The selected remedies for soils are: 1) in-situ vapor extraction
with treatment by vapor phase granular activated carbon (GAG) ,
and 2) excavation and treatment by aeration to meet federal,
state, and local air standards. Most of the vapor extraction will
be performed on soils inside of the existing Fairchild and
Raytheon slurry walls, where the highest concentrations of soil
contamination are found. The vapor extraction is estimated to be
in operation from 1 to 6 years. The excavation and treatment of
contaminated soils may invoke RCRA Landban requirements which
would also require treatment to meet BOAT standards. Intel has
previously excavated and aerated their contaminated soil under
RWQCB orders. These selected remedial alternatives will likely be
used at other potential sources in the MEW area. EPA expects soil
remediation to be implemented by the PRPs.
The soil cleanup goals for the MEW area are: 0.5 parts per
million (ppm) TCE for all soils outside of the slurry walls and l
ppm TCE for soils inside the slurry walls. The cleanup goal for
soils outside of the slurry walls is based upon the amount of
contamination that can remain in the soil, leach into the
groundwater and still achieve the cleanup goal for the shallow
aquifers. The rationale for the use of a higher cleanup goal for
soils bounded by the slurry walls is presented in the following
discussion. Although the aquifers bounded by the slurry walls are
considered potential drinking water sources, this groundwater is
effectively isolated when local hydraulic control is implemented
by pumping inside the confines of the slurry walls. This
isolation of contaminated groundwater and soil bounded by the
slurry walls provides an additional level of protection of the
significantly larger drinking water source outside of the slurry
walls. This additional level of protection through the use of a
slurry wall system (slurry wall and hydraulic control) allows for
a higher soil cleanup goal for soils confined by the slurry
walls. But, the use of the 1 ppm TCE cleanup level for these
soils is dependent upon the continued operation of a pumping
system which maintains local hydraulic control of groundwater
inside the slurry walls. If local hydraulic control by pumping
was to cease, then the lower soil cleanup goal of 0.5 ppm TCE
would need to be attained. In summary, the soil cleanup goal is
higher inside of the slurry walls because of the extra degree of
protectiveness provided by the slurry walls in conjunction with
the maintenance of inward and upward gradients into the area
confined by the slurry walls, with a system of hydraulic control
by pumping of groundwater. To ensure that the slurry wall system
is effectively working, regular monitoring will be performed of
local groundwater quality and water elevations. During the
22
-------
duration of,the remedy, there will be an evaluation of the remedy
and cleanup goals at least every five years. .
The selected groundwater remedy is hydraulic ~emediation by
groundwater extraction and treatment. The groundwater cleanup
goals by pumping and treatment are: 5 ppb TCE for the shallow
aquiters (including the aquifers inside the slurry walls) and 0.8
ppb TCE for the C and Deep aquifers. The cleanup goa1 is more
stringent for the C and Deep aquifers, because they are currently
used as a supply for municipal drinking water and will 'be
technically easier to remediate than the shallow aquifers. The
0.8 ppb cleanup goal corresponds to a 10.' cumulative (human)
cancer risk.
Although, the shallow aquifers are not currently used for drinking
water, they are a potential source for'drinking water and
therefore a 5 ppb TCE clean~ goal has been established which'
corresponds to between a 10. and 10.5 excess cancer risk, which
is within EPA's acceptable risk range. Cancer risks have been,
screened for all aquifers and the chemical ratio of TCE to other
chemicals found at the site is such 'that achieving the cleanup
goal for TCE will result in cleanup of the other site chemicals
to at least the~r respective MCLs.
The estimated time to reach the deep aquifer cleanup goal is
between 2 to 45 years. The time to reach the shallow aquifer.
cleanup goal may be considerably longer, possibly from 46 'years
or into the indefinite future, because of the physical and
chemical nature of the shallow aquifers. They are, low yielding
and contain soils with a high clay' content which attract and
retain the site chemicals. During the duration of the remedial
effort, both shallow and deep aquifers will be regularly
monitored for water ~ality and groundwater elevations.
The extracted groundwa~er will be treated largely by air
strippers, although some companies (e.g., Intel) may use their
existing liquid phaseGAC units. The three currently operating
air strippers have been permitted by the Bay Area Air Quality
Management District and are not using'emissions controls. The air
stripper stacks have been designed to meet risk levels of <10.6
excess cancers. We anticipate that with the additional air
strippers to be installed arid the increased flow rates during
full scale remediation, emissions controls will likely be needed
to meet more stringent air district standards. The emissions
controls will consist of GAC vapor phase carbon units.
The extracted groundwater will be reused to the maximum extent
feasible, with 100' reuse as a q~al. The remaining extracted
groundwater will be discharged under NPDES requirements to
stevens Creek. Work has already commenced on various vater reuse
options, which will be presented and implemented during the RD/RA
phase.
23
-------
The remedy also includes the identification and sealing of any
conduits or potential conduits, using the decision process
outlined in the FS. Several identified abandoned agriculture
wells have allowed contamination to migrate from the shallow
aquifers to the deep aquifers. These wells have subsequently been
sealed. Additional wells have been identified for sealing and
other wells may also be identified during RD/RA phase which will
require sealing. .
TO evaluate the effectiveness of remedial actions and to
determine when cleanup goals are attained, regular monitoring of
chemical concentrations and water elevations is. required at .
selected wells across the site. For soil cleanup, EPA will need
to concur on a method to determine when the required cleanup
goals have been achieved.
The estimated costs of the selected remedies are provided in
Table 12-1 and include the use of emission~ controls, .well
sealing, and monitoring . The total .cost of the remedies, in
present worth dollars, is estimated to be between$49M to $56M.
14.0 STATUTORY DETERMINATIONS
The selected remedies are protective of human health and the
environment -- as required by Section 121 of CERCLA-- in that
contamination in groundwater is treated to at least MCLs and
falls within EPA' s acceptable risk range of 10-4 to 10-7. In
addition, the remedy at least attains the requirements of all
ARARs, including Federal and State MCLs.
Furthermore, as shown on Table 12-1, the groundwater remedy -
pumping, and 'treating with air strippers and the soil remedy -
vapor extraction, are cost effective technologies. Soil
excavation with aeration has also been shown to be cost effective
when it was used at the Intel facility, and may also be used at
other facilities.
The selected remedies will permanently and significantly reduce
the toxicity, mobility, and volume of hazardous substances with
respect to their presence in soils and groundwater. The use of
vapor extraction for soils is an innovative treatment technology
for removing VOCs.
Contamination is controlled and removed from the groundwater,
thereby reducing the ~vtential threat to the nearby public water
supply wells and also restoring the aquifers to meet drinking
water standards. The slurry walls in conjunction with pumping and
treatment reduces toxicity, volume and mobility of contamination
to migrate from major source areas. The sealing of conduit wells
24
-------
will reduce the likelihood of vertical migration of
contamination.
Emissions from soil vapor extraction will be controlled by vapor
phase GAC. Emissions from air stripping towers will meet local
air district requirements, which are anticipated to be a 10-6
risk level, and therefore will likely require vapor phase GAC.
The regeneration of spent carbon from the GAC emission controls
will meet all Federal, state, and local requirements.
25
-------
A'1"1'ACJDCD1TS --
-------
RBSPOBSIVBJIBSS SOIOIARY
-------
RESPONSIVENESS SUHHARY FOR THE FAIRCHILD, INTEL, AND RAYTHEON SITES
KIDDLEFIELD-ELLIS-WHISMAN (K-E-Y) STUDY AREA
Kouncain View, California.
1.
COMMUNITY RELATIONS HISTORY
EPA has carried on an accive community relaCions program ac the Kiddlefield-
Ellis-Whisman (MEtJ) Study Area.
In early 1986, EPA, in conjunceion wich Sanea Clara County, inieiaced monthly
meetings for all agencies involved in hazardous waste investigation and cleanup
to review and coordinate activities. Representatives of local, state and federal
agencies, elected officials, business and industry and public interest groups
attend the meetings. The meetings continue on-a quarterly basis.
In che spring of 1986, new contamination was found in Kountain View's deep
aquifer This discovery marked the first time contamination had been detected at
those depths in that part of Santa Clara County. In response to community
concerns and questions about the safety of the drinking water supply, EPA
prepared a fact sheec describing che sicuation and disCributed ic to the site
mailing lisc.
In Kay 1986, EPA worked wich Fairchild Semiconductor Corp. Co prepared a 4-
page insert for Kountain View'.s The View to explain Fairchild's proposal Co
construct three slurry walls in order Co confine cheir sice's contaminaced soils
and to pump and treaC waCer confined by the walls.
In February 1987, Raytheon and EPAworked togecher to prepare anocher insert
for The View thac described Raytheon's proposed slurry wall to contain
concaminacion around their site.
In June 1987, EPA worked with Raycheon, Intel and Fairchild to produce an
insert for The View describing che draft Remedial Invescigacion (RI) report.
In November 1988, EPA released a Feasibility Study (FS) on the Kiddlefield-
Ellis-Whisman Study Are to the public. The report described and evaluated
various clean-up alcernatives based on daca and supporc documencs available at
the time. EPA's preferred alternatives were: vapor extraction and treatment for
soils, pumping and creating for shallow and deep aquifers; and vapor excraction,
groundwacer control and creatmenc for the slurry wall syscems.
. .
In fulfl1lmenc of community parcicipatlon requirements, EPA held a public
comment period from November 21, 1988, through January 23, 1989; briefings of
local officials and community members; and a community meeting. EPA also
prepared a Proposed Plan fact sheet which outlined the range of cleanup
alternatives, cleanup goals, and EPA's preferred alternative for dist~ibution to
the site mailing list. Prior to the fact sheec, EPAalso released a press
advisory announcing che range of alternatives and EPA's preferred alternative.
1
-------
The community meeting was held December 14, 1988, to present clean-up
alternatives, to answer questions and to take comments on the FS. Comments
centered on the length of the cleanup period and on who would do the cleanup.
Written comments on EPA's Proposed Plan focussed on the following issues:
cleanup levels for soil and groundwater, length of public comment period,
variations in the text of the FSreport, and length of cleanup time. Responses
to public comments are addressed in the attached response summary. Most of the
c~mments were submitted by Potential~y Responsible Parties.
II.
SUMMARY OF PUBLIC COMMENTS AND AGENCY RESPONSES
Technical Comments
1. Comment: Several comments concerned the number and location of recovery
wells to be placed in the MEW area.
EPA ResDonse: The Feasibility Study (FS) and Proposed Plan are not design
documencs. The exact number and location of recovery wells will be determined
during cheremedial design phase.
2. Comment: NASA-Ames Research Center.had several concerns: 1. how the
proposed treatment. system would handle grounCiwater contaminated with fuel, 2',
how other cleanup actions may be influenced by the proposed recovery wells, 3.
. the effects. that the proposed hydraulic remediation may have on existing'
contamination at NASA-Ames and the adjacent Moffett Naval Air Station.
EPA ReSDonse: The above concerns
Remedial Action (RD/RA) phases.
coordination will be required by
successful remediation program.
will be addressed during the Remedial design and
Obviously, a large degree of cooperation and
the affected parties during ~/RA, to ensure a
3. Comment: "The FS proposes to remediate soils using in situ soil aeration.
Air inlet wells may also be installed to increase the efficiency of the soil
aeration system. It is suggested that if air inlet wells are to be installed they
should be used to control the extent of an in situ negative soil air pressure
field, not to increase soil air flow through the contaminated soils. If they are
installed solely for the purpose of increasing airflow across the contaminated
. so11 particles, their use is questionable." .
EPA ReSDonse: VOC's have a marked tendency to partition into the s01l
atmosphere. The rate of desorption into pore space is principally a function of
chemical diffusion in response to a concentration gradient. Sweeping of clean air
through a soil matrix increases the concentration gradient and therefore
increases partitioning and the overall efficiency of the in situ soil aeration
system. The result of creating a negative air pressure field, with an in situ air
stripping system, does have a minor effect on soil-air partitioning, but the
field tends to be localized around the extraction welles) ~.~ci the overall effect...
is negligible. The key to an efficient in situ vapor extraction system is
increasing the airflow across contaminated soil particles and not simply to
2
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control the negative soil air pressure field. The use of air inlet wells will be
analyzed further during the RD/RA phases of this project.
Comments On EPA's Process
1. Comment: Several commenters who are Potentially Responsible Parties (PRPs)
stated that the comment period was too short to adequately review the FS and
Remedial Investigation (RI) report. Requests were made to extend the comment
period.
EPA Resnonse: . The National Contingency Plan (NCP) requires that the RI, FS and
Proposed Plan be provided 'to the public for review and comment for a period of at
least 21 calendar days. The new proposed NCP requires a minimum 30 calendar day
public cOlIIIIDent period.
EPA has
comment
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names. \le will also be periodically updating our aailing list and will contac t
local officials and community groups for assistance in updating that list.
S. Comment: A number of commenters claimed that they were not PRPs. Some of
these commenters also cited references to other PRPs or inferred sources, in the
RI report. .
EPA ReSDonse: The determination of who is or who is not a PRP is not relevant to
the selection of a remedy. Furthermore. in its August 8. 1988 approval of the RI
report. -EPA neither agrees nor disagrees with the assumptions or assertions
regarding 'inferred sources or other PRPs' as presented in the RI report.- EPA
aakes its own determination of liability independent of the RI/lS process.
6. Comment: Several commenters who are PRPs wanted to know how other PRPs will
be dealt with, how cleanup costs will be allocated, and who is responsible for
cleanup. .
EPA ReSDonse: EPA is currently evaluating PRPs to determine who will receive
Special Notice letters for Remedial Design and Remedial Action (RD/RA) to 17
parties. The responsibility for cleanup lies with whomever EPA determines to be
a PRP. The allocation of cleanup costs are usually decided among the PRPs.
7. Comment: Two PRPs wrote that remediation of the C and deep aquifers should
be addressed as a separate operable unit. The reasons given were that the C and
deep aquifer contamination is limited to localized areas" the contamination was
not caused by the respective commenters, and, operation and maintenance cost will
be increased. .
EPA Resnonse:~ EPA does not designate operable units to separate cost allocations
among various PRPs. The commentershave offered no compelling technical or
environmental reasons why there should be a separate operable unit for the C and
deep aquifer remediation. EPA believes that including the deep aquifers in the
comprehensive remedial plan for the entire MEW Study Area is the most efficient
use of agency and PRP resources. Furthermore, 40 CFR Section 300.6 simply
defines an operable unit, -as a discrete part of the entire response action that
decreases a release, threat of release, or pathway of exposure.-
The Followini Selected Comments Concemin, EPA's Process \lere Submitted by Siltec
1. Comment: Page 1. Siltec claims that a copy of the final RI was not made
available to them until January 13, 1989. Siltec has not had a reasonable
opportunity to review or comment on all. of RI's contents.
EPA ResDonse: A draft RI has been in the Kountain View public library since July
1987. The final RI was delivered in July, 1988, to EPA and the Kountain View
Public Library. Siltec has had ample time to review the RI since EPA stated at
the October 1988 -kickoff- meeting attended by Siltec representatives, that the
final RI was available for review in the EPA and Kountain View libraries.
Siltecseems to be arguing that EPA should have had a separate public notice for
the RI. citing U.S. v. SeYmour Recycling Corp. 679 F. Supp.859 at 864.' If that
4
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is Siltec's contention, EPA disagrees. EPA notes that a separate RI review
process is simply not contemplated by CERCLA nor U.S. v.Seymour Recyclini Corp.
679 F. Supp 859 (S.D. Ind. 1987); In that case, the court notes that~ pursuant to
CERCLA as amended by SARA, the generator defendants are entitled to comment on
the selection of a remedy before the remedy is selected. In U.S. v. Seymour
Recvclirii CorP., as here, EPA provided the generator defendants an opportunity to
comment on the remedy before a selection of the remedy has been made.
EPA also notes that Siltec was given notice that it was a potential responsible
party in the HEW area in May, 1985 ~nd was given an opportunity to participate in
the RI/FS process. Thus, Siltec was on notice that the RI/FS was being prepared,
and therefore, Siltec should have been tracking the progress of the RI/FS.
2. Comment..;.. Pages 3-4. Siltec has been unable to comment on the FS because of
substantial uncertainty about the accuracy and validity of the FS distributed for
public comment. . .
EPA Response: EPAdisagrees with the statement that "there is substantial
uncertainty about the accuracy and validity of the FS distributed for public
comment." As stated above, the FS was available to the public in the EPA and
Mountain View libraries at the beginning of the comment period, November 21,
1988. In addition, copies of the FS were also available for purchase from
Canonie Engineers. Any inconsistency between the copies was minor in nature.
3. Comment: Siltec stated that "[T]he opportunity for meaningful comment is
compromised where complete copies of relevant agency documents have not been made
available in a timely fashion" citing the case of U.S. v. ROM and Haas Co. Inc.
669 F. Supp. 672, 683. . .
EPA Response: The facts of U.S. v. Rohn and Haas COmPany. Inc. are very
different than here. In particular, the public was given 5.days to submit
comments in U.S. v. . Rohm and Haas COmPany. Inc. Here the public, including
Siltec, was given 64 days to submit comments. .
4. Comment: Siltec recommends that cleanup of the C aquifer (the
the B-C aquitard) should be addressed as a separable operable unit
defined at 40 CFR Section 300,6 and as permitted by 40 CFR Section
areas below
as the term is
300.68(c). .
EPA Respon~ 40 CFR Section 300.6 simply defines an operable unit as "a
discrete part of the entire response action that decreases a release, threat of
release, or pathway of exposure." EPA fails to see the benefit of addressing the
C aquifer as a separate operable unit solely for cost allocation purposes.
The Followini Selected Comments Concerninl EPA's Process Were Submitted bv Air
Products
1. Comment: "EPA does not have the power to create or affect liability of
persons at a 'Superfund site' simply by drawing the 'site boundary' at one
location versus another."
5
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EPA Res~onse: The FS does not address the liability of persons at the HEY site.
EPA notes that liability is determined by CERCLASection 107, not the drawing of
site boundaries. .
2. Comment: -EPA lacks the authority under Section 104 to order Air Products to
require testing."
EPA Res~onse:
the RI and FS.
Orders requiring testing under Section 104 are not addressed in
EPA notes Air Product's legal opinion.
Comments Concernin, the Pro~osed Cleanu~ Goals
1. Comment: The Regional ~ater Quality Control Board (RWQCB) commented that the
cleanup goal for the groundwater inside the slurry.walls should be set at 5 parts
per billion (ppb) -- the same goal set for the groundwater outside of the slurry
walls. The Board commented that EPA's groundwater' classification applies to all
aquifers.including aquifers within slurry walls.
EPA Res~onse: EPA's Proposed Plan recommended a 5 ppb cleanup goal for the
shallow aquifers. Although not specifically stated, this 5 ppb goal would also
apply to the aquifers within the slurry walls.
2. Comment: The R~QCB a150 commented that the cleanup goal for soils within the
slurry walls should be set at .5 parts per million (ppm) ~- the same level for
soils outside the slurry walls. The Board was concerned about relying solely on
slurry walls to prevent migration of contamination -because the long term
integrity of slurry walls has not been demonstrated."
EPA Res~onse: In addition to pumping within the slurry walls (to assure an
inward gradient), there will be continuous monitoring of water levels and
chemical concentration inside and outside of the ~lurry walls. Performance
monitoring will be an integral part of any RDjRA Consent Decree. In the ev~nt of
a slurry wall failure, additional measures can be taken such as, modification of
the walls and pumping rates, or applying more stringent cleanup levels inside the
slurry walls. . . .
3. Comment: The Santa Clara Valley ~ater District (SCVWD) commented that they
would not prevent a well from tapping the shallow aquifers.
EPA ResDonse:
Comment acknowledged.
4. Comment: The SCVWD 1s concerned that a cleanup goal has not been established
for the aquifers within the slurry walls.
EPA ResDonse:
See EPA response to comment no. 1.
5. Comment: The SCVWD commented that specific protocol should be developed for
reviewing and evaluating the performance of the selected remedy.
EPA Res~onse: -~he RDjRA process will incorporate specific criteria for
evaluating the cleanup goals and the effectiveness of the remedy. The cleanup.
goals and remedy will be evaluated at least once every 5 years.
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6. Commen~ The SCVWD recommended that a cleanup goal of 0.8 ppb also be
established for the shallow aquifers.
EPA Resnonse: A 5 ppb cleanup goal is protective of human health, especially
since these aquifers are not currently used for drinking water. The 5 ppb level
also falls within EPA's acceptable risk range of 10.. to 10.7.
In addition, the cleanup goal may not even be technically feasible because the
aquifers are relatively "tight" (lo~ water bearing zones) and have a high clay
content, thereby making chemical removal difficult and costly.
7 . Comment: The League of \lomen Voters urged EPA to use a, "hazard index" to
establish cleanup goals instead of the Maximum Contaminant Level (KCL) for TCE.
The League is concerned about the "mixtures o~ chemicals" and their effects and
cited the IBM and Fairchild sites in San Jose where the hazard index was used.
EPA ReSDonse: EPA believes that a 5 ppb TCE cleanup goal for the shallow
aquifers is protective of human health. See EPA response to the SCVWD.
. .
The. ratio of TCE to other chemicals (found at the site) is high enough that a 5
ppb cleanup of TCE will result in a' cleanup of the other chemicals below their
corresponding KCLs. The 5 ppb cleanup goal takes into. account the additive
effects of the chemicals found at the site, and the resulting risk falls within
EPA's acceptable range of 10-. to 10-7. '.
The IBM and Fairchild San Jose sites have TCA as the dominant chemical. Drinking
water'wells have a150 been affected at the IBM and Fairchild sites in San Jose,
while no drinking water wells have been impacted at KEW.
8. Comment: One commenter wrote that Alternative Concentrations Limits (ACLs)
would be appropriate "if no health risk occurs through exposure by contact or
through ingestion of the contaminated groundwater." The commenter questioned
whether such exposures can be prevented. .
EPA ResDon~ EPA is not proposing the use of ACLs at this time.
applicability of ACLs will be determined during subsequent review
the remedy has been implemented and periodically evaluated.
The
periods, once
The Followin2 Selected Comments Concernini CleanuD Goals \lere Submitted By
Crosby. Heaflv. Roach and Kav. a Law Firm ReDresentin, Sobrato DeveloDment
1. Comment: The 5 ppb cleanup level for the shallow aquifers "is not necessary
to protect human health and safety", and the cleanup level "is unreasonably
burdensome and cost inefficient. The firm also wrote that the shallow aquifers.
"are not reasonably anticipated to become suppliers of drinking water in the near
or distant future", and that the enforcement of existing institutional controls
can be used to protect human health. Therefore, less stringent standards should
be applied to the shallow aquifers namely 500 ppb.' ..'
7
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EPA ReSDonse: It should first be noted that EPA has proposed cleanup 1081s
rather than cleanup levels. These goals and the remedies ,will be evaluated
periodically to determine if they are technically practical, and therefore they
may be subject ~o modification. "
EPA based its proposed cleanup goals on several factors:, 1. The ,shallow aquifers
are potential drinking water sources even though they are not currently being
used for drinking. This determination is also consistent with the Regional Water
Quality Control Board's Basin Plan and Non-Degradation Policy which are designed'
to protect natural resources; 2. ~e 5 ppb goal meets £lA's acceptable risk
range of 10-4 to 10-7:. The 500 ppb cleanup level which the commenter is
proposing would exceed this acceptable risk; 3. It i. unlikely that all of the
abandoned agriculture wells which are-currently acting as conduits or are ",
potential conduits threatening the deep (current drinking water) aquifers will.
ever be located and properly sealed. Experience has shown that abandoned wells
(e.g., Rezende,s Wells) can cause significant contamination to migrate from the
shallow aquifers to the deep aquifers.' Therefore, absent sealing all of the
abandoned wells, it becomes necessary to reduce the contamination in the shallow
aquifers. The 5 ppb level would then be the maxiDIWII level that could potentially
migrate to the deep aquifers.
2. Comment: -The worst case scenario soil remediation application is
inappropriate.- The commenter objected to-uniform application of the worst-case
scenario to the entire HEW area. The commenter also stated that future use
assumptions of the HEW site are inconsistent with the City of Mountain View
General Plan and with California Health and Safety Code institutional controls.
EPA ResDonse: Because multiple sources have impacted a common groundwater area
with commingled contaminant plumes (which threaten a current drinking water.
supply), EPA believes that a uniform application of a reasonable -worst-case"
scenario and a uniform application of cleanup goals is the most efficient method
to assure the' protection of public health. This is also consistent with,the
approach taken at other sites in Santa Clara Valley and the country. Although
the City of Mountain View's General plan may currently call for'
industrial/commercial use of the site, General Plans and land use are subject to
change. The site is also presently bordered by residences west of Whisman and on
Moffett Naval Air Station, and a change in the electronics industry may make
residential use of the site plausible in the future. Other than deed
notifications, it is not clear to which institutional controls of the California
Health and Safety Code the commenter is referring. '
ReSDonse To Selected Comments From Sobrato
1. Comment: -The MEW FS purports to apply a percolation rate of 2 inches/year
in calculating the allowable contamination concentrations in the soil. Such a
percolation rate is considered extremely unlikely in properties, like SOBRATO's,
which have been covered and contained by asphalt. In addition, surface ~off at
the site is comprehensively routed to storm sewers and drains. Therefore,
percolation rates on the SOBRATO properties should be expected to~?proach nearly
zero.- '
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EPA ResDonse: Although field studies have not been conducted at the MEW site to
determine tbe amount of water infiltrating through the topsoil, the literature
describes exponentially decreasing infiltration rates following a rainstorm.
However, oore water may infiltrate to the aquifers in periods of long storms,
especially following extended dry periods.
. .
The scenario of calculating soil remediation levels, by assuming potential
residential use rather than current industrial usage, is EPA policy. This policy
has been consistently applied throughout other regions under similar'
circumstances. The rationale supporting this policy is that surface coverings and
land use may change and, o~er the long term, institutional controls may be
unreliable. The 2 irich/year percolation rate 1s applied consistently throughout
the KE\l area.
2. Comment: .Ye (Sobrato) would like to point out that if the rationale
the basis for the California Assessment Manual (Ca. Admin. Code Title 22,
Division 4, Chapter 30, Article 11) criteria is applied to the subject
properties, the soil cleanup level would be, at a minimUm, 5.0 mglkg."
used as
EPA Res1)o~- The criteria presented in the cited California Administrative Code
defines a regulated hazardous waste and is not appropriate for determining a soil
cleanup level.
- The Followin~ Selected Comments Yere' Submitted by Heller. Ehrman. White &
McAuliffe. Attornevs for NEC Electronics. Inc.
1. Comment: The intended application of the "No Further Action" (monitoring
only) alternative is unclear, since it is discussed primarily for Zone I s01ls
located inside slurry walls.
EPA ReSDonse: EPA does not understand the comment, as we believe the application
of the "No Further Action" alternative is adequately explained for each of the
remedial alternatives in Chapter 8 of the FS.
2. Comment: No estimates of the remediation periods for "Partial Excavation
with Ambient Temperature Aeration" (Alternative 3) and "Partial EXcavation and
Ambient Temperature Aeration with In Situ 50il Aeration" (Alternative 4) are
provided. .
EPA ResDonse: The time frame for this alternative would be governed by the
factors- identified in Appendices G and H of the F5, which state that the
remediation of excavated soils requires 48 hours of disking soils in six inch
lifts. The number of lifts required would depend upon the volume of soil to be
remediated. Table 0-22 of Appendix ° provides the volume of soils to be
excavated and remediated.
3. Comment: NECElectronics requested the "latitude" to explore other "options"
including those remedial me~hods outlined in the FS, and other methods in order
to achieve the,!OD cleanup goals for vadose zone soils.
9
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EPA Resconse: EPA anticipates that the MEW FS will be applied as appropriate to
other sites in the MEW area. The remedy, in-situ vapor extraction, was selected
based on a thorough ,evaluation of the alternatives. In addition, soil excavation
and treatment by aeration was also selected, based on prior implementation in
MEW. If new information or alternatives are brought to the attention of the
agency in the future, the EPA may consider them.
4. Comment: It is highly unlikely that contamination in the Rezendes ~ells
could have come from NEC's 501 Ellis Street facilities.
EPA Resconse: The specific origins.of the Rezendes ~ells' contamination is not
an issue in the selection of a remedy, nor is liability for the deep aquifers,
since Superfund liability i5 strict, joint, and several.
5. Comment: When shallow groundwater is mixed with deep aqui,fer groundwater in
the same treatment system, there will be a "deleterious effect on the water so
treated." This mixed groundwater will have limited uses "if surface discharge is
rejected as an alternative after treatment."
EPA Resconse: While this appears to be mainly true for the A and Bl aquifers.
most of the B2and B3 aquifers would not require treatment for major ions and
coliform bacteria. See Table 1-6 (Volume I) of the Remedial Investigation
Report. Furthermore, the 8deleterious effects8 of mixing the deep and shallow
ground waters in a treatment system will ultimately be determined by the end use
of the water. '
6. Comment: The effects of long term pumping of the shallow aquifers should be
carefully evaluated in li.ght of recent experience with. a similar system at other
sites in the region.' It is not clear if recharge rates and aquifer yields have
been evaluated.
EPA Resconse: While it is not clear to which other sites in the region the
commenter is referring,. aquifer'yields and recharge rates will be thoroughly
evaluated during RD and before any full scale remediation beings. In addition,
water levels, subsidence, etc. will be carefully monitored during RA.
7. Comment: There is no indication that scaling and biological growth in the
air stripping columns have been considered in treatment facility design or in the
operation and maintenance costs (O&K) shown in the FS.
EPA Resconse: The operation and maintenance cost estimates for the treatment
systems include packing replacement and acid feed system maintenance. which are
intended to solve or prevent scaling and biological growth problems. (Appendices
J and K) . ' ,
8. Comment: 8There is no indication that the FS has corisidered the costs of
complete replacement of treatment units in the annualO&H costs or the capital
costs for the facilities."
EPA Resconse: The annual operation and maintenance costs for each treatment
system includes replacement costs (e.g., $6,000 for blower repair or replacement,
10
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$11,500 for packing replacement, $14,000 'to $22,000 for the acid feed system,
$1,000 for electrical controls, and $3,000 to $4,000 for the air stripper tower).
Resnonse To
Selected Comments From Siltec
Comments on Soil Remediation Levels
1. General Comment: The proposed soil remediation level of 0.5 ppm TCE for all
soils throughout the MEW site which lie outside the slurry walls is not
adequately supported by the FS. We '(Siltec) believe that a 0.5 ppm TCE soil
remediation level is incorrectly calculated and incorrectly expressed for several
reasons.
2. Comment: The FS states that supporting justification and analysis for
~election of a soil remediation level is based on a 8worstcase8 hypothetical
exposure scenario where the MEW site would be converted to an unpaved residential
area characterized by open lawns and unsewered roof drains allowing maximum
infiltration and subsequent percolation (FS, Appendix Q, p. Q-IO). We (Siltec)
believe the RI/FS errs in using the worst case analysis to identify the soil
remediation level. An appropriate analysis should consider other more probable
scenarios as the basis for selection of soil remedy for the MEW Study Area.
EPA Resnonse to Comments 1 and 2: The scenario of calculating soil remediation
levels by assuming potential residential exposure is EPA policy. This policy
has, been consistently' applied throughout other regions under similar
circumstances. The rationale supporting this policy is that land use can change
and, over the long term, institutional controls (e.g., zoning and local planning)
may not be reliable.
In addition, the modeling scenario in Appendix Q is certainly not an extreme
worst case. ,The following items are examples:
The model allows for instantaneous dilution with the groundwater aquifers
below the contaminated soil zone., In the real world, instantaneous mixing
would not occur leading to higher concentrations in the upper portion of
the aquifer than predicted by the model. The instantaneous mixing given by
the model allows for a dilution of 89 times (0.0112). At many sites
throughout the country, where similar evaluations are performed, no
groundwater dilution would be allowed. The given model assumes the
receptor to be at the boundary of the contaminated zone. In many
instances, a theoretical receptor's well would be modeled directly below
the site. If all of the examples given above were incorporated into the
model, much higher receptor concentrations would be predicted. The result
would be much lower soil clean up levels. .
Because of the facts given above, the model is considered a reasonable worst case
scenario, not an extreme worst case.' This is consistent with EPA guidance.
3. Comment: Further time sensitive analysis such as the analysis provided in
Table Q-9 is useful to evaluate the degree of potential harm as measured by
various conservative assumptions. Table Q-9, for example, shows that health based
11
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levels of TCE in the aquifer would be approached for only one year in a thirty-
year period and that otherwise the level of TCE in groundwater would be below
those leve 18 .
EPA Resnonse: Table Q-9 represents one case (conservative in concentration and
percolation, not conservative in Kd) from the potential cases given on Table Q-3.
Other cases could be performed. Given different scenarios, (e.g.; longer areas,
higher soil concentrations and lower dilution), long term elevated groundwater
concentrations could easily be greater than 5 ug/L. '
4. Comment: The worst-case analysis used to support a soil remediation level of
0.5 ppm TCE in soil assumes a percolation rate of 2 inches/year. 'However, the
EPA approved model used to arrive at, percolation rates is stated'to result in
.virtually no percolation to the saturated zone.. The FS use of a 2 inch
percolation rate'is based on a theoretical possibility of the effect, of prolonged
Pacific frontal systems. No justification for or analysis of the effect of the
frontal system is given by the FS. 1£ a worst case analysis is used at all, the
soil remediation level analysis should be calculated using a lower percolation
rate. '
EPA Resnonse: Although field studies have not been conducted at the MEW site to
determine the amount of water infiltrating through the topsoil, the literature
describes exponentially decreasing infiltration rates following a rainstorm.
However, more water may infiltrate to the aquifers in periods of long storms,
especially following extended dry periods. '
Assumptions used in the EPA model resulted in calculating little or no
infiltration- 'in the MEW area. This model uses average monthly precipitation and
temperatures to calculate average monthly evapotranspiration r~tes and
percolation rates. As a result, the percolation model does not consider the
single storm event. Infiltration calculations based on single storm events may
yield higher computed percolation'rates. Also, the percolation model uses only
precipitation as "a water input. Additional surface water recharge can be caused
by irrigation related to landscaping. Based on these factors and conservative
engineering judgment, the FS used a percolation rate of two inches/year.
5. Comment: The worst-case scenario is inconsistently applied for soil
remediation levels. The 1 ppm TCE soil remediation level for inside the slurry
walls is based on the implicit assumption that those areas will remain under'
industrial/commercial control necessary to maintain effectiveness of the slurry
walls. ' '
EPA Resnonse: A residential reasonable worst-case scenario was uniformlY,applied
throughout the MEW area. The 1 ppm TCE cleanup goal was based on the added
degree of protection provided by the slurry walls and the continued monitoring
and pumping which will be part of the overall remedy, regardless of the existing
or potential land use.
6. Comment: The worst case assumption stated in the FS at Appendix Q uses a
retardation factor of 6.0. Based on Appendix peA, -the worst case retardation
factor discover-ed by the-.nalysis lies at a minimum range of 6.5-8.5 as measured
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by laboracory daca and ac 7.0 as measured by field daCa. Any calculacions
involving worsc case assumpcions should use chese higher recardacion faccors.
EPA Resnonse: Table Q-9 is based on R of 12.0. Use of a R of 6.0 is
conservacive buc cercainly noC worsc case. Many adsorpcion R values may be as low
as 2.2 for TCE. Desorpcion R values may be much higher. .Worsc case. analysis
should use lower R values noC higher as implied.
7. Comment: The soil remediation analysis is ostensibly calculated so as to
demonstraCe protection of the underlying aquifer as measured by a health based
concentration of 5 ppb TCE in the aquifer. On this basis, the FS concludes that
0.5 ppm TCE in soil is an appropriate soil remediation level. However, the.
solution to the equations provided in the analysis have apparently been solved to
result in no more than 4.85 ppb TCE in the underlying aquifer.
EPA Resnonse: The difference between 4.85 and 5.0 and the use of .standard
scientific conventions" (i.e., significant figures) versus .nonstandard
convention" is trivial and meaningless to argue over given the accuracy of the
methodology and the assumptions. For example, the difference between 0.0111 and
0.0112 (the dllucion factor) is noc meaningful or che difference is noc
significanc. . .
8.
Commen~
"
. the FS incorrectly calculaces the value for (Q in)!. .
n
EPA Resnonse: The referenced calculations; have been reviewed and found to be
correct. A typographical error exists in (Qin)!, which should be expressed in
ft3/year. Despite the typographical error, the correct units were actually used
and che calculation in che FS are correct as scated.
9. Commen~. . the actual analysis provided to support the soil
remediacion level is expressed as a concentration of TCE in soil ner snecified
unic of available SQuare surface area throuih whichnercolation mav occur. Based
on chis analysis, it is inadequate to express the remediation level for che .
entire site without reference to the corresponding surface area."
EPA Resnonse: Using che site specific approach given in Appendix Q requires
areas of contamination to be used in the calculations. A similar calculation can
be made using percolation through a unit surface area through a given mass
resulting in flux into groundwater. The remediation levels calculated from these
approaches are presented in terms of mglkg. Soil clean-up levels need to be in
terms of mglkg for application of an area-wide clean-up goal and for verification
of remediation. .
10. Comment:
(RSCLs) .
The FS is unclear as to the use of. recommended soil cleanup levels
EPA Resnonse: RSCLs were ~ used co determine soil cleanup levels at MEW.
fact, RSCLs are outdated and are no longer used, even by the California
Department of Health Services.
In
13
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11. Comment: S11tec recommended that a cleanup level greater than 1 ppm for TCE
beset, based on soil cleanup levels "found at" other relevant Superfund ~ites.
The sites referred to are found in New Hampshire, Rhode Island and Michigan.
EPA Resnonse: A cleanup level established for one site (especially in another
part of the country) is not necessarily adequate at other sites. Site
characteristics can vary greatly (e.g., soil, groundwater, geology, affected
populations, etc.) and, therefore, each site must be evaluated on a case-by-case
basis.
11.
Comment::
The RI report incorrectly stated that Siltec used TCA.
EPA Resnonse: Comment noted, however, EPA in its August 8, 1988 approval letter
for the RI stated, "EPA neither agrees nor disagrees with the assumptions or .
assertions regarding 'inferred sources' or 'other PRPs' as presented in the RI
report."
13. Comment: " . . TCE contamination in the groundwater is not attributable to
leaks from an above ground storage tank and groundwater flow beneath Siltec
property is to the northeast."
EPA Resnonse: See above response. In its RI approval letter, EPA also stated,
"EPA neither agrees nor disagrees with the configurations and boundaries of the
chemical plumes, or with the graphi~al interpretation of the potentiometric
surface/water table of each aquifer as presented in the RI report." "The
configuration and boundaries are, however, adequate to evaluate remedial
alternatives." The points raised by Siltec are minor since they deal with only a
small por~ion of the MEV area, and therefore are unlikely to have any bearing on
the selection of remedial alternatives for the overall area. Furthermore, well
elevation data and TCE concentration contour plumes have been reviewed and the
data substantiates that the groundwater (in the shallow aquifers) flows in a
north or northwest direction, consistent with the RI report.
14. . Comment: Soil remediation at Siltec would be unnecessary if soil
remediation levels were "properly derived", therefore, the statement in
that on-site soil remediation is necessary at Siltec should be stricken
text.
the FS
from the
EPA Resnonse: Soil remediation levels for the HEW area have been properly
derived. Individual sites which will require soil remediation will be determined
by EPA-on a case-by-case basis.
15. Comment: Siltec believes that the effects of sanitary and storm sewers as
potential conduits in the local study area (LSA) have not been adequately studied
and that further investigation may show that sewers in the LSA do act as
conduits. .
EPA Resnonse: An adequate evaluation of potential horizontal conduits was
performed by Fairchild, Intel, and Raytheon as part of the RI. The results of
the investigation were included in the RI report. The report concluded that
horizontal conduits (at least within the loca. study area) are not a problem.
Siltec wishes to perform an additional study, it may do so during RD/RA.
If
14
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The Followini Selected Comments Were Submitted bv the Lea~e of Women Voters
1. Comment: Identification of all
to increase the financial resources
is also essential to guarantee that
participating in the cleanup."
the responsible parties should be expedited
needed for cleanup. "Close monitoring by EPA
all polluters have been identified and are
EPA Resnonse: EPA has issued "Spec~al Notice" letters for cleanup liability to
17 Potentially Responsible Parties (PRPs) in the HEW area. Agency negotiations
vith the PRPs for cleanup and oversight costs vill commence shortly. In
addition, as cleanup progresses, monitoring data vill be evaluated to determine
if other sources have contributed or are contributing to the HEW contamination:
2. Comment: The League agrees with the "pump and treat alternative" for the
shallow aquifers.
EPA Resnonse:
Comment noted.
3. Comment:
groundwater. .
The Proposed Plan should identify ways of reusing extracted
EPA Resnonse: Groundwater reuse is currently being evaluated and will be
incorporated into the ROD and the RDfRA Consent Decree.
The Followini Comments Were Submitted bv the U.S. Navv,
General <::ollllents
1. "Unlike other FS reports, this report does not present supporting engineering
calculations on treatment sizing, pumping requirements, simulated drawdown cones,
or construction materials and methods. ~ such, the document is generic in
nature and essentially requires the reader to assume that the black box system is
optimal." .
EPA Resnonse: Such detailed design information is typically ~ provided in the.
FS because it is unnecessary, and consequently will be presented during Remedial
Design (RD).
2. "The report does not present specific design information for water treatment,
soi1s aeration, and several other alternatives discussed. Without this.
fundamental information, it is impossible to critique the authors conclusions."
EPA Resnonse: The information presented in the report'is sufficient for
evaluating various alternatives. Specific design information will be presented
during RD'.
3. WA groundwater model is not specified, and pumping specifics (e.g., rate,
duration, equipment) are not provided."
15
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EPA Resnonse: The information regarding the groundwater model can be found in
Appendix P of the Feasibility Study.
4. .Offsite remediation is mentioned throughout the document in a cursory manner,
yet a number of pumping wells are shown on NAS Moffett Field property and a
treatment system is shown on NASA property. Hov was the information gathered in
the NAS Moffett Field Remedial Investigation incorporated into the treatment
designs and ground vater extraction schemes?. .
EPA Resnonse: As the FS report states, the number and location of pumping wells
and treatment systems1s for costing' estimates only. The actual number and
location of these units vill be provided during RD. Also, site specific sources
on Moffett Field vere.not incorporated into the treatment designs and extraction
schemes. .
5. .The document does not present information as to the potential timing for
installation of off site or on site remediation. Due to other investigations
currently ongoing, extensive coordination is needed.. To date, what coordination
is proposed?" .
EPA Resnonse: Timing and coordination for vell installation will be part of the
Remedial Design and Remedial Action (RDjRA) negotiations process, and therefore
are not incorporated into theFS.
6. "It was difficult to determine if the unsaturated zone model is accurate
without supporting calculations. In addition, hov is differentiation made
between vapor phase transport and liquid phase transport?"
EPA Resnonse: Supporting calculations for the unsaturated zone model are found
in Appendix P of the FS. Vapor phase transport was not considered.
Executive Summary
1. "ES-l. Uncontrolled sources are cited as present and impacting potential
remediation. These sources are not clearly defined in the text nor are their
impacts."
EPA Resnonse:' Uncontrolled sources will be defined during the RDjRA phase and as
other PRPs are included in the process.
2. "ES-l. It is stated that the FS is designed to adequately address unknown or
uncontrolled sources of pollution. . No reference vas found in the text that
presents how uncontrolled sources are handled in the FS design process."
EPA Resnonse:
See response above.
3. .£S-2. Chemicals have been detected in all 5 aquifers. \las there any
investigation as to the vertical distribution of chemicals in any of the'
aquifers, particularly the C aquifer?"
16
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EPA Res'Donse: Section 4..0 of the Remedial Investigation Report (July, 1987 and
revised June, 1988) contains the results of a thorough investigation of the
chemical distribution in 50ils and groundwater in all aquifers.
4. "ES-2. How was the total volume of TCE, TCA, etc. calculated? This was not
described in the text."
EPA Res'Donse: The estimation of volumes of chemicals in various aquifers is
described in Section 4.3.2 (pp. 4-63 through 4-66) of the RI Report.
5. "Shallow aquifers beneath the site are cited by the R\lQCB as being a potential
drinking water source. This argument appears unfounded since the general water
quality is poor and the aquifers thin, discontinuous, and low yielding. How much
potential does .EPA or RYQCB see for the shallow aquifers being utilized as a
drinking water source?"
EPA Res'Donse: While the water quality and yields of the shallow aquifers may be
lesser in relation to the deep aquifers, the shallow aquifers near the site have
been used for drinking water in the past, according to the Santa Clara Valley
Yater District. Although currently no one is using the shallow aquifers for
drinking water, the aquifers do meet EPA's groundwater classification criteri.!r.
for potential drinking water sources and are also protected under the RYQCB's
Basin Plan and Non-Degradation policy. Both agencies regard the shallow aquifers
as a resource that should be protected and restored.
6. "ES-5. The upper foot of soil is not considered for remediation based on
health risk. Yas potential leaching of these materials and subsequent
concentrations in lower zones considered?"
EPA Res'Donse: The Endangerment Assessment prepared by
is very little cont~ination present in surface soils,
the surface soils) is unlikely to be a problem.
EPA concluded that there
therefore, leaching (from
7. "ES-7. Throughout the document, maintaining an inward and upward hydraulic
gradient has been discussed. However, calculations on how much water should be
pumped to establish this gradient or exactly what minimum magnitude of the
gradient is necessary but not present."
EPA Res'Donse:
.Yater pumpage will be determined during RD/RA.
Chapter 1
1. "PI2... Recent groundwater extraction from within the slurry walls is
presented. There does not appear to be any reference in the text as to the
quantity of water being pumped or the quality of effluent. This type of
information is critical in evaluating appropriate remedial alternatives. No
reference is made as to the established NPDES levels to Stevens Creek or the
POTY. This information is vital in establishing cost effective disposal
options. " .
17
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EPA ResDonse: . EPA does not believe that this information is necessary for the FS
report. The information will be provided during the RD phase.. NPDES levels may
be obtained fro. the RWQCB.
Chapter 2
1. .P-17. Three additional recovery wells were added
rationale behind their installation? Where are they?
one treatment system? If so, was the original system
treatment system?"
in 1985. What was the
Do they all couple into
redesigned? Where is the
2. .P-17. TWenty-one (26?) recovery wells are apparently now operating. A
schematic of the operating system(s) is essential along with design details and
rationale. None of this information is provided making a good review of
additional pump and treat scenarios difficult."
3. "P-18; Three stripping towers are said.to treat some portion of the recovered
water. What portion goes to the POTV and to Stevens Creek?"
EPA ResDonse: The above information is not necessary for .the FS and will be
provided during the RD phase.
4. "P-22.
aquifer.
. .
The Raytheon slurry wall is said to partially penetrate the B2
Why was the wall keyed into permeable materials?"
EPA ReSDonse: This information may be obtained by reading the Raytheon "Slurry
Wall Construction Report" Golder Associates, January 1988, which is' on file at
EPA and i5 also part of th~ administrative record. .
5. "P-23. 1,300 Ibs. and 230 Ibs. of VOCs were removed from two plots.
percentage recovery of VOCs was achieved?"
What
EPA ReSDonse:
This will not be known until the remedy has been completed.
6. "P-24. In-situ tests apparently suggest an effective radius of influence of
40 feet for venting wells. The specifics of these tests were not presented.
What were the physical soil properties? Soil moisture and temperature? Total
concentration of chemicals in the soil? Generally, in the fine gra1ned s01ls,
vent wells are placed on 5 to 10 feet centers. Although it 1s not possible to
check the authors' calculations, previous experience suggests that the vent
system as given may not be adequate."
EPA ResDonse: The
Extraction Study",
February 8, 1988.
the administrative
information may be found in a report titled, "Soil Vapor
Raytheon Company, prepared by Harding Lawson Associates dated,
The report is available for review at EPA and 1s also part of
record.
7. .P-26. The slurry wall around Fairchild building 9 appears to be built
th"'<:,;ugh a highly contaminated area. Why? (See figure 2 -1. 6) "
EPA Res'Donse:
This information is not relevant to the proposed cleanup plan.
18
.
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8. wP-27. Ke~als have been de~ec~ed in ~he groundwa~er bu~ are essen~ially
discoun~ed because of ~he s~a~emen~: "Ke~als...are no~ very mobile in .
groundwater...w. The presence of metals in the soils and groundwater should be
considered in ~e design of ~reatmen~ alternatives. Ke~als present in ~he high
ppb range may have adverse affec~s on potential treatment options such as
biological reac~ors and promote scaling in air s~ripping towers~"
EPA ReSDonse:
Ketals will be considered during RD.
9. .P-33. Chemical concentrations were detected in Stevens Creek. What were ~he
concentrations of ~ese chemicals? ,How were ~hese chemicals addressed in NPDES
permitting a~ the site?W
EPA ReSDonse: This information is not relevant to the FS.
requirements may be obtained from the RWQCB.
NPDES permitting
10.WP-33. How were the synergistic and antagonistic effects of the various non
target chemicals addressed when designing water treatment sys~ems? For example,'
is fouling of the aeration ~ower packing ma~erial due ~o high levels of
inorganics a po~en~ial problem a~ the HEW remedia~iori area?
EPA ReSDonse:
This information will be developed during' RD.
11. .P-34. Chemicals de~ec~ed in samples below lOX or 5x associa~ed field blanks
are repor~ed as non-de~ec~ed. Which specific compounds o~her ~han ~he four. .
chemicals lis~ed fell under the lOX rule? On wha~ basis was ~he 5X rule chosen?"
EPA ResDonse: This informa~ioncan be found in ~he .Endangermen~ Assessment"
repor~ available at EPA and in the Ci~y ofKoun~ain View Public Library.
12. wP-36. . The mobili~y of me~als is again men~ioned ye~ there is no discussion
on ~he redox po~en~ial, precipita~ion or exchange of ~ese chemicals in ~he '
presence of soil componen~s such as humic acids. Lead for example can be
solubilized by some naturally occurring acids and some lead compounds produced
are classified as soluble. If lead is able ~ocome in con~ac~ with es~uarine
benthic microbes through surface water transpor~ or shallow 'groundwater flow, .
these microbes can methylate lead to form tetramethyl lead which is volatile and
more toxic. Although situations like the one described 'are not common, a more
comprehensive review of metals contamination should be considered."
EPA ReSDonse:
See above response and response to comment 8.
Chapter 3
1. wP-54. In ~aragraph 2, soil remediation levels are lef~ open, yet all
remedial alternatives are based on 1 ppm and 0.5 ppm TCE cleanup levels.
apparent inconsistency needs clarification."
This
EPA ReSDonse: Soil remedia~ion levels inside the slurry walls !!'J".'e .lef~ open" ,t~>'
only if Alternative Concentration Levels (ACLs) are chosen as cleanup levels for
19
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aquifers inside the slurry walls. EPA has chosen Maximum Contaminant Levels
(MCLs) for the shallow aquifers including those located inside slurry walls.
2. "P-57. The federal pre-treatment guidelines for toxics of 1.37 ppm from
manufacturing facilities would be relevant only if the local treatment works
would agree to use this guideline."
EPA Response: Correct.
Chapter 5
1. "P-92/106. In°situ biological treatment is considered only to a very limited
extent. Specifically, the authors address biodegradation in an undisturbed
state. Further they discount this option quickly by citing a single study
performed by Stanford University. No significant conclusions were drawn from
this work.
Aerobic biodegradation can be performed using an above grade landfarming
technique. This technique is very successful with aromatic hydrocarbons and
would augment soil aeration. The technique can be used with similar farm
equipment employed by the aeration alternative. Although biodegradation alone is
not a plausible solution, biodegradation using marine bacteria, sewage sludge or
some strains of soil bacteria can enhance the remove of chlorinated alphatics
sorbed to the soil matrix and should be considered."
EPA Response^ Comment noted.
2. "P-95. On site-treatment options deal exclusively with volatile compounds.
The extracted water stream will,contain numerous other chemicals such as iron,
magnesium, calcium carbonate, and heavy metals. These compounds must be treated
prior to entry into an aeration tower to prevent fouling and to promote treatment
to the limits set. Treatment units including precipitation tanks-and mixers, in
line filtration, and multimedia filtration should be addressed."
EPA Response: This will be addressed during RD.
3. "P-101. The chemical characteristics listed are properties associated with
volatilization and sorption. Characteristics such as pH, TDS, BOO and TSS need
to be quantified prior to design of water treatment."
EPA Response: Comment noted.
4. "P-103. The contention that additional surface capping would have a minimal
influence on infiltration should be supported by calculations provided in the
document."
EPA Response: Most of the site (approx. 80%) is already capped. Therefore,
additional capping will have little, if any, influence.
5. "P-104. It is contended that excavation would require demolition of several
buildings. Which buildings?"
20
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EPA Resnonse:
Potentially, any building.situated over soil contamination.
6. .P-10S. Limited space available for stockpiling soils is given as a reason to
discard excavation, yet 1andfarming soils for volatilization of organics is.
passed through for consideration. If space is limited, where would the above
grade landfarming be accomplished?"
EPA Resnonse:
This information will be developed during RD.
7. .P-108. Aeration is described as not being effective on phenol.
treatment method is offered for phenol in lieu of aeration. Why?
However, no
. EPA Resnonse: As phenols in soil have not been quantitatively defined,
information vill be developed during RD, and. incorporated as necessary into the
treatment .ethods. .
8. .P-108. What constitutes successful dewatering? (para 4). If vapor
extraction is to be successful, what is the maximum residual water content in
sandy soils1 .Cohesive soils1"
EPA Resnonse:
.This information will be developed during RD.
9. .P-108. Adverse settling due to dewatering was encountered. What was the
magnitude of this settlement? Why was this situation not reviewed in Chapter 9
with respect to the long term pumping scheme?" .
EPA Resnons~ It is not known if settlement was due in part, solely, or at all
because of dewatering. . Additional information will be developed during RD/RA.
10. .P-10S. It is stated that settling will not affec.t slurry wall integrity.
Were calculations performed to support this contention?"
EPA Response: The FS Report states .that settlement conditions, are not expected
to affect the integrity of the slurry walls. Calculations to support this
conclusion were performed by consultants for Raytheon independent of the FS
report.' .
11. "P-109. The report claims that in-situ aeration is applicable to soils
beneath buildings. It is not clear from the supplied figures how soils beneath
buildings are being remediated."
EPA Respons~ Soils beneath buildings are not currently being ,remediated.
areas will be addressed during RD/RA.
Those
12. .P-109.
What are the serious concerns about steam injections?"
13. .P-109. What are the potential adverse effects of steam flushing?
not presented in the discussion."
They are
EPA Respons~~ The concerns about steam injections are that the levels of
development and field experience are minimal. Massive injections of steam would
result in tbe significant elevation of subsurface soil temperatures and pore
21
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pressures under structures on the site.
result in possible injuries to personnel
due to 1. heave or settlement and/or 2.
steam to the surface.
These temperatures and pressures could
and disruption of industrial operations
the accidental uncontrolled release of
14. .P-112. The arguments that flushing may increase the boundaries of chemical-
bearing groundwater and that the flow injected water cannot be controlled are not
valid. If injection wells are properly placed up gradient of the plume and
extraction wells placed downgradient, a closed loop system can be maintained.
Flushing increases the hydraulic gradient and can substantially reduce
remediation time. Further, flow controllers connected to sensQrs in monitor
wells can maintain a predetermined hydraulic head..
EPA Resnonse: Sections 5.3.11, 5.3.25, 6.2.9, 7.2.2.4, and 7.2.3.4 of the FS
explain why flushing is not considered for site remediation.
15. .P-112. 1. It is stated in the FS that it is unlikely that enough water
could be:'injected to alter the piezometric surface. This argument contradicts
the previous statement regarding complex stratigraphy. The aquifers are low
yielding, discontinuous and relatively thin bedded. All of these physical
characteristics suggest an induced head could be applied. 2. Yere calculations
performed or. a flow model used to show the effects of water injection?"
EPA Resnonse: 1. The text of the FS does not contradict the above statement.
The text does state that due to the .extremely variable permeabilities . . . it
(1s) impossible to ensure that adequate flushing rates can be maintained in all.
. . areas. Also, it is unlikely that it will be possible to inject groundwater
at a rate that would significantly alter water levels or piezometric surfaces in
areas not in the immediate vicinity of the injection well.. 2. No.
Chapter 7
1. .P-160. An 80 foot square grid would be required according to section
7.2.1.2. Earlier in the report, a 35 foot spacing was presented."
EPA Resnonse:
during'RA.
The exact spacing is unknown at this time, but will be determined
2. .P-160. In figures 7.2-1 a-c, extraction wells are shown but air inlet wells
are not shown. The text describes inlet/extraction wells. Is this a pump in,
pullout process or just vapor extraction?"
EPA Resnonse:
The process will be determined during RD.
Chapter 9
1. .P-260. Stevens Creek is proposed as the ultimate receptor for treated
groundwater although it is not specifically stated in this chapter. How will the
added flow affect the stream channel? '
EPA Resnonse: As described in Section 2.2(pp 2-4) of the RI Report, St~v~ns
Creek is an intermittent stream. Therefore, the addition of a year-round flow ,of
22
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treated grcmndwater from MEW Area remedial actions aight change portions of the
creek downstream of groundvater discharge points to a perennial condition, to the
extent that the discharge flow exceeded local stream bed percolation capacity.
However, the proposed flow of treated groundwater is not expected to be large
enough, when compared to normal storm run off, to materially affect the channel.
2. "P-260. Have channel hydraulics been modelled using the HEC-1 or similar
flood routing scheme to ensure that the added water will not create a local
flooding problem?"
EPA Response: No.
3. "P-245. Seven tenths of a pound of TCE is considered to be de minimus. How
is this value calculated (weight or volume basis)? What criteria is used for
determining the volume or weight to test?"
EPA Response: The term "de minimus" was developed by Fairchild, Intel, and
Raytheon to describe certain "minor" contaminated areas. EPA does not use this
terminology to describe contaminated areas. Calculations and criteria may be
found in Appendix 0 of the FS report.
4. "P-245. How was the pumping scheme outside the slurry walls designed to
ensure that an upward gradient is maintained inside the slurry walls? If the
groundwater surface is sufficiently suppressed outside the walls then inside
pumping is negated."
EPA Response: The gradients are currently being monitored and will be monitored
during RD/RA.
5. "P-260. Why are only Bl and A aquifer wells proposed offsite in the
downgradient direction?"
EPA Response: Because there is no contamination downgradient in the B2 and B3
aquifers.
6. "P-260. What is the rationale for placement of wells within NAS Moffett
Field? Was. flow modelling performed?"
EPA Response: Wells were placed in relation to the contamination plume. Flow
modelling was not performed.
7. "P-260. Since chemical transport modelling was accomplished in only two
dimensions, how were the effects of drawdown of chemicals through shallow
aquitards considered?"
EPA Response: The effects of drawdown of chemicals through shallow aquitards
were not considered since the model assumes that the aquifer is confined.
8. "P-261. Air stripping and activated carbon filtration are listed as treatment
components. Will these systems require continuous monitoring?"
EPA Response: No.
23
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9. "P-26l. What are the estimated carbon use rates and packing life spans?
other components comprise the treatment systems? How much area will be
required?" .
What:
10. "P-26l.
How will utilities be handled for the off site systems?"
11. "P-266. What is the rationale for the placement of the three .C. aquifer
wells? What are the proposed pumping rates? Will the higher volume pumped from
the .C. aquifer have a tendency to dilute the waste stream from the lower
yielding upper aquifer vells? If so, what is the expected average concentration
of chemicals on the influent side of the air stripper?" .
EPA Resvonse:
The information for questions 9-11 will be developed during RD.
12. "P-267. The Operation and Maintenance costs are not well defined in the
appendices. How was the 2.9 million dollars of annual O&M derived for the off
site, remediation scheme? How many treatment systems are included in the off site
program?"
EPA Resnonse: The O&M costs are adequate for the'purposes of. the FS.
number of treatment systems will be developed ~ing RD.
The exact
13. "Figure 9.2-4. Some fairly extensive piping is shown on NAS Moffett Field
property. .How would this piping be installed? Have the numerous subgrade
utilities on the facility been factored into the estimated cost?"
[PAResnonse: The drawn piping is a conceptual design and the installation will
be refined during RD. . Yes.
24
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ADXIBJ:STRATIVB RBCORD IIIJ)B%
-------
REVISION DATE: OS/22/89 PAGE: 1
. .
Mfddlefield-Ellis-WhiS88ft Area SUperfund Sfte
Mcq,t8in View, c.Ufomfa
- AdIIfnfstrative Racord IrQtx --
l! em. FRat/ORGAN I ZA T J ON TO/ORGAN J ZATION DESCRJPTJON/SUBJECT PAGES
06/11176 Malcol8 Burns Ccu'lty Sanitariens Yell SnUng Jnstructions 7
Santa Clara Valley Water Dist. Varfous Dr...ings
'
.
~
2 02108/85 Roger 8. J-t Revised.Tentative Order 8
RW0C8
SF Bay Region
3 03/20/85 ThOll8s Berld ns Donald Dalke su...ry Reports for the 13
R.W.Q.C.B. R.W.Q.C.B. Mcq,tain View Five
SF Bay Region SF Bay Region
4 04/22/85 ThORBS Berkins, Lester Roger J8IIeS Fairchild, Intel, NEC, 8
Feldman, Lawrence Kolb R.W.Q.C.B. Raytheon, Siltec, Mountain
R.W.Q.C.B. SF Bay Region SF Bay Region View, Santa Clara Co.
5 04/30/85 R.W.Q.C.B. Fairchild, Jntel, NEC, 2
SF Bay Region Raytheon, Siltec, Mountain
Vfew. Santa Clara County
Require.ents for Site Cleanup
"6 07/26/85 Gordon Snow Glenn Kistner State Review of Mountain View
Resources Agency of Cal ifomia EPA Region 9 Five SUperfund Project
7 08/15/85 Ilarding, Lawson Assoc.: EPA Region 9 Work Plan R~ial Investig. 75
Canonie Engineers Feasibility Study and Oper-
ational Unit Feasibility Study
Middlefield Ellis'Whisman Area
8 08/15/85 EPA Region 9 Intel, Fairchild & Raytheon Administrative Order on 22
Consent
9 08/15/85 Lloyd R. Day Eric G- L8A'8la Mountain View RJ/FS end
Cooley. Godw8rd, Castro. Harding. Lawson Assoc. O.U.F.S.
Ituddleson & Tatun
..
10 08/31/85. Terrence J.~ McManus Glenn Kistner Project Schedule 6
Intel EPA Region 9
11
09/06/85
Terrence "~
Intel
Glenn Kistner
EPA Region 9 '
Project Schedule
5
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REVISION DATE: OS/22/89
PAGE: 2
Middlefield-Ellia-Whisman Arm Superfund Site
Mountain View, California
••• Administrative Racord Indax •*•
DOC » DATE FROM/ORGANIZATION
12 09/25/85 Canonie Engineers
TO/ORCAM1ZAT10M
EPA Region 9
DESCRIPTION/SUBJECT
Addendum: QAIQC Plan Existing
Monitoring Wells RIFS Middle-
field-Ellis-Whisman (MEW)
Area
PAGE?
175
13 09/25/85 Steve Dobrijevic, Phillip
Antomaria
Canonie Engineers
Intel
Monitoring Report Remedial
Investigation Feasibility
Study Date Through July 1985
175
U 10/28/85 Jaws McClure, Eric I appal a
Harding Lawson Assoc.
EPA Region 9
Technical Memo: Well Inventory
Middlefield-EUis-Whisman
Study Area RI/FS
25
15
11/15/85 Canonie Engineers
Intel. Fairchild & Raytheon
Soil Evaluation Report
Remedial Investigation
Feasibility Study
Volume I
175
16
11/15/85 Canonie Engineers
Intel, Fairchild I Raytheon
Soil Evaluation Report
Remedial Investigation
Feasibility Study
Volume II
175
17
11/15/85 Canonie Engineers
Intel Fairchild ft Raytheon
Soil Evaluation Report
Remedial Investigation
Feasibility Study
Volume III
150
18 11/22/85 James McClure, Eric Lappala
Harding, Lawson Assoc.
EPA Region 9
Technical Memo: Potential
Conduits Evaluation Middle-
field Ellis-Whisman Study Area
35
19 11/26/85 Glenn Cistner
EPA Region 9
20 12/00/85 Canonie Engineers
Terrence McManus
Intel
Intel, Fairchild ft Raytheon,
Si Itec
EPA Comments on the Database
Management System Plan,
Hydrogeologic Model Plan,
Well Inventory
Pumping Test, City of.
Mountain View
Well No. 18
200
21
22
12/20/85
Glenn Kistner
EPA Region 9
01/00/86 Canonie Engineering
Terrence McManus
Intel
Fairchild
Preliminary Definition of 22
Remedial Action Objectives
MEW Study Area
Mountain View, CA (cover Itr)
Pumping Tests Interim Remedial 300
Program Mountain View Facility
Volume 1 of 2
-------
REVISION DATE: OS/22189 PAGE: 3
Middlefield-Ellis-WhiS88ft Area SUperfund Site
Mcultain Vf..., CIIl ffomfa
- AcDfnistratfw Record Index -
.~ ~ FROM/ORGANIZATION TO/ORGAN I ZATiON DESCRIPTION/SUBJECT ~
01/00/86 Canonie Engineers Fai rchild Pulpfng Tests Interi. 300
Re8edfal Proer- Mcultain View
Fecil fty Vol~ 2 of 2
"
24 01/28/96 Glem Kistner T er:rence MdC8nu8 EPA C088eftts to the Middle- 12
EPA Region 9 Intel field-Ellis-WhiS88n Study Area
'"Soi l Eyaluat i on Report"
25 01/28//86 Glem Kistner Thomes TrflR) Additional EPA comments 3.
EPA Region 9 Landels Ripley £ Di880nd coneemini the "Soil
Eyaluation Report" and
Fairchild
26 01/30/86 Glem Kistner Terrence Md4anJS EPA C088eftts on the "Existing 17
EPA Region 9 Intel Data Review" for the Middle-
. field-Ell is-Whisman Study Area
Remedial Investigation
27 02100/86 Canonie Engineers Intel, Fairchild' R-rtheon Historic Flow Analysis 22
Hydrogeologic Model Descrip-
tion R..-dial Investigation
Feasibility Study
02125/86 Catherine Henrich, EPA Regi on 9 Third Quarterly Report "R..-d- 40
Ed c Lappela ial. Investigation Feasibility
H&rding Lawson Assoc. Study Niddlefield-Ellis-
Whisman Study Area
29 02/25/86 Hardi ng Lawson Assoc. EPA Region 9 Tables Third Quarterly Report: 100
R..-dial Investigation/feasi-
bility Study Middlefield-Ellis
WhiS88n Study Area
30 02/27/86 Canonie Engineers u.S. EPA Responses to EPA Comments on 60
For Intel, Fairchild & the Nfddlefield-El l is-Whisman
Raytheon Area RI/FS Soil Eyaluation
Report
31 02/27/86 Philip L. Fitzwater Glem Kistner Tr8n88ittal: Reports in reply .15
Harding Lawson Assoc. EPA Region 9 to EPA ~ts on the "Soil
Evaluation Report"
32 03/12/86. .Glem Kistner Larry A80n EPA and COIIIp8ny Agreellents 2
EPA Region 9 Fai rchild
03/26/86
Catherine Henrich,
Eric Lappala
Harding Lawson Assoc.
Glem lCistner
EPA Region 9
Trans.ittal: Chronology of
Eyents and Chemical Results
fr~ SWI-230, RJC and R4C
100
-------
RF.VISION OATE: OS/22/89
PAGE: lo
Middlefield-EllIs-Whi..-n Ares Superfund Site
Mountein Vi_, Californie
-- Acilinistretiw Record Index --
22U
34
2m
03/28/86
FROM/ORGAN I UTION
Glenn Kistner
EPA Regi on 9
TOIORGAII I UTI ON
Larry Man
Intel
DESCRIPTION/SUBJECT
Initiel Screening of
Altemlltiws
~~ES.
4
35
04/03/86
Glenn Kistner
. EPA Region 9
Larry Man
Fair~i ld
Delay re ~ifi.r Test Report
36 04/04/86 Glenn Kistner Larry Amon EPA's draft comments on: 10
EPA Region 9 Fairchild -Monitoring Network Well
Sun88ry- Historic Flow Anal-
ysis Hydrogeologic Model
31 04/04/86 Rona~d Stoufer & Phillip Raytheon Pha.. IV Subsurface Investi - 150
Fitzwater gation Raytheon 350 Ellis St.
Harding Lawson Assoc. Mcx.ttain View,Ca.
38 04/07186 James Wilson, Eric Lappela EPA Region 9 Quality Assuranc:e/Quality Con' 135
Harding Lawson Assoc. trol Plan: Remedial Invest i-
gation Feasibility Study and
Operable unit, feesibility
39 05/00/86 Internetionaf Technology Intel SUb8urlace Soi l Re88diation 310
Intel
Meentain View, CA
40 05/02/86 Michael Rosa Glenn lCistner RI/fS Schedule
Raytheon EPA Region 9
41
05/09/86
Glenn Kistner
EPA Region 9
Michael Rosa
Raytheon
Deep Well Moni toring Program
2
42 05/13/86 Canonie Engineers Fai reM ld Investigation of Well 652W22A3 32
Silva Well, Remedial. Investi.
gation Feasibility Study
Middlefield-ElliS-Whismen Area
43 OS/20/86 . Michael 8. Rosa Ji. Grove Deep ~ifer Monitoring 8
Raytheon EPA Region 9 progr. .
44
OS/21/86
Dennis fesmire
Canonie Environmental
File
Attachaent 8 Contact with
Garcia Well end P~ Co.
2
-------
> itEVISIO'" DATE: 05/22/89 PAGE: 5
Niddlefield-Ellfa-Whi..-n Area SUperfund Site
Mcu\tafn Vi..., Cal ffomia
- Ac8iniatratfw Record Indo -
! Rm F1tCM/CIUiAJII ZA T JON TO/ORGAIIJZA TJON DESCRIPTION/SUBJECT ~
05/21/86 SteYO DObrijevic Larry Man Status Report Fairchild 300
Phillip Ant08l8ria Fai rchi ld > Mcu\tain View Facility 9/1/85
C8a'tie Engineers through 3131186
Vol. I
46 05/27/86 Stew Dobri jevic Larry Man Status Report Fairchild> 210
Phillip Ant~ri. Fai'rchi ld Mcu\tain Vi.. Faci l i ty
Cannonie Erigineers 9/1/85> through 3131/86
Vol. 2
47 06/00/86 Cenonie Engineers Intel, Fairchild & Raytheon Area North of aayshore '5
Freeway Re.edial Investigation
Feasibility Study
48 06/00/86 CanonieEngineers Fai rchild Draft Report: Interi. Remedial 10
ActiOns Fairchild Semiconduct.
Nt. View Facility
Volune 1 of 3
49 06/00/86 Cenonie' Engineers Fairchild Draft Report: Interi.Remedial 200
Actions Fairchild Semi conduct.
Nt. Vi.. Facility
Vol. 2 of 3
06/00186 C8a'tie Engineers Fairchild Draft Report: Interi.Re8edial 400
Actions Fairchild Seliconduct.
Nt. Vi.. Facility
Vol. 3 of 3
51 06/02/86 Bryan Rector Glenn Kistner Intel Groundwater Re8edial 25Q
Intel EPA Region 9 Actions Attached: ~roundwater
Re.edial Actions Final Phase
3/19/86
52 06/05/86 Michael Rosa Glenn Kistner Schedule for S8q)l ing ROU'Id 200
Raytheon EPA Region 9 3.5 Niddlefield-Ellis-~isman
RI/FS
53 06/12/86 P .K. Ch~ttopectlY8Y .Ii. Wilson Request for Laboratory 6
Ecology & Environment Harding Lawson Assoe. Analytical Ra.. Data
Mountain Vi.. Site
.
54 06/16/86 Robert P. Stem Mountain View Cleanup
EPA Region 9
06/17/86
Terry Wi lson
EPA Region 9
Press (News Releaae)
EPA R,~t Publ i c Call1lent
On Fairchild Groundwater
Cleanup Plans, in Mountain View
-------
IIPEVISIONDATE: OS/22/89 PAGE: 6
Middlefield-Ellls-Whi..-n Area SUperfund Site
~taln VI_. C8llfornia
- Ac8inistretiw Record Index -
2!;U gm FROM/ORGAN I ZA T I ON TOICRGAIII ZAT ION DESCRIPTION/SUBJECT J»AGE~
.56 06/23/86 Mlch..l Rosa Glern Kistner Notification of Additional 28
Raytheon EPA Region 9 Groundwllter 8811pl i"ll for the
Middlefield-Ellis-Whi..-n
RI/FS
51 07/00/86 Middlefield-Ellls-WhI..-n Area 7
RI/FS Well Inventory SUmlary
ProcU:tion Wells
58 07/00/86 Canonie Engineers Fairchild Parking Structure Private ~ell 25
Investigations and Proposed
~l l Sealing Plan ME\i
Area, Mt. View, California
59 07/00/86 Canonie Engineer Fairchild Deep Well Cluster NUlCer 3 D\J3 25
Installation & Pumping Chrono-
logy Middlefield-Ellis-Whisman
Area Mountain View, CA
60 07107/86 Michael Kent Robert Stem Fairchild Interi. Remedial 3
. Citizens for a Better EPA Action Proposal
. Emi rornent
61 07/08/86 Glern Kfstner Mlch..l Rosa Well Inventory" Potential 5
EPA Region 9 Raytheon Ccnduits Evaluation
62
07/23/86
Harry Seraydarian
EPA Region 9
Larry AllIn
D i 8IIIOf'Id IlII8ges
Interim Remedial Actions
Report
63 07/24/86 Phillip Antommaria Raytheon B-C Acuitard Soil Chelllical 60
Canoni. Engineers Analysis Results Middlefield-
Ellis-Whism8n Area Mountain
View, CA
64 01/3/86 Mich..l Rosa Glem Kistner Draft Map showing distribution 3
Raytheon EPA Region 9 and classification of wells In
MEV study Area
65 01/29/86 Michael Rosa Glem IClstner Lost ~ell. 2
Raytheon EPA Region 9
66
08/00/86
Canonie Engineers
Intel, Fairchild" Raytheon
Soil S8q)ling end Analysis
R8IIIedial Investigation
Feasibility Study
25
-------
REVISION DATE: 05/W89
PAGE: 7
Middlefield-Ellfs-WhiS88n°Area SUperfund Sfte
Mountain Vi..., C8l ifomia
... AGIinistratiw Record Index ...
iI
!!ill
08/20/86
FROM/ORGANIZATION
Eugenia Zorid1
Harding L8WGI'I Assoc.
TO/ORGANIZATION
Glem leistner
EPA Region 9
DESCRIPTION/SUBJECT 0
Tr8nS8ittal of Status Report
""ter Gu8lity S488ry 350
Ellis St. Mountain View, CA
8-8-86
O~
135
.
68
08/25/86
Mid1ael Rosa
R-vtheon
Glem leistner
EPA Region 9
Response to July 8 EPA Letter
on Potential Conduits
15
69 09/04/86 Harding Lawson Assoc. EPA Region 9 ~l ing Plan: Remedial Inves- 210
tigation Feasibility Study
Middlefield-Ellis-~isman
Study Area Mountain View, CA
070 09/05/86 Canonie Envir~tal Faird1lld Evaluation Report Stevens 25
Creek Recharge: Groundwater
Treatment Fairchild Mountain
. Vi... hcll ity
71 09/11186 Glem leistner Mid1ael G. Rosa 8-27-86 Technical Meeting of ,
EPA Region 9 Raytheon the Agencies 8nd COIIIp8nief!
09126/86
Glem leistner
EPA Region 9
Mid1ael Rou
Raytheon
Short and Long Ten8 Aquifier
Test Report
11
73 . 09/30/86 David Ie. Rogers Bryan Rector Transmittal of Summary aeport 200
The Mark Group Intel Soil And Groundwater Data
Intel Site Mountain View, CA
74 10/07/86 Stevo Dobrijevic , Phillip Michael Rosa Response to EPA Comments on 25
AntC88ria Raytheon the Construction DW6 Nul tiple
eancnie Engineers Monitoring Wells in a Single
Borehole
75 10/14/86 Stevo DObrijevic Th088S Bertti ns Additional Infon88tion 110
Phillip Arit08m8ria R.W.G.C.B- Pertaining to Stevens Creek
Canonie Environmental
76 10/20/86 Stevo DObrijevic C.R. Bostic Non-RI/FS ""ter Gu8lity Data 100
Cancnie Envi rORllerttal Fai rchild Fai rchild Mountain Vi..., CA
10/20/86
Eugenia Zorich
James McClure
Harding Lawson Assoc.
EPA Region 9
Interi. Round Water Quality
Sa.pling Report: Remedial
Investig./Feasibility Study
160
-------
REVISION DATE: 05/22/89
Middlefiel~Ellis-WhiS88n Area SUperfund Site
Mo&8\tain VI.., c.tffomla
- Adlinistratiw Record Index -
.~
78
FROC/ORGAN I ZAT ION
Demf. L. Curren
Canonie Environ8ental
DESCRIPTION/SUBJECT
Reapanse to EPA ec-nts
. Tedmical Me80 Perting Struc-
ture Privete Well Investi~a~
tions with Att~ts. .
TO/ORGANIZATION
Glem Kistner
EPA Region 9
~
10/21/86
79
Gle.m Kistner
EPA Region 9
Response to EPA ec-rtts Tech-
nical Me80 Parting Structure
Privete Weu Investigations
And Proposed weu Seating Plan
10/21/86
Demis Curren
Canonie Environ81tal
80
Phillip Antammaria
Stevo Dobrijevic
Canonie Environmental
11/21/86
C.R. Bostic
Fairchild
Technical Me80 Wel I Inventory
and Evaluation Update Middle-
field-Ellis.Whisaan Area
Remedial Investigation
81
11/21/86
Glem lCistner
EPA Region 9
C.R. Bostic
Fairchild
R~es to Aquifer Test
Report Coaments
82
11/24/86
Stevo Dobrijevic
CanonieEnvironmental
C.R. Bostic
Fairchild
Transllittal: Observation Wells
Fllirchi ld Mountain View, CA,
PAGE: 8
~
20
10
11
15
100
83 11/24/86 C.R. Bostic Glem Kfatner Water Level Data Fr~ ,1 -86 7
Fairchild EPA Regi on 9 Through 12/86 for the 'c' and
" Deeper Aquifer Wells, RemecHal
Investigation Feasibil i ty Stdy
84 12/00/86 Camp Dresser & McKee EPA Region 9 Final CCIIIIU'Iity Relations Plan 40
Middlefield-Ellis-Whisman Area
Mountain View, CA
85 12/19/86 Oemis J. Curren Glem lCistner Tr8nS8ittal Historic Water 200
eanonie Environmental EPA Region 9 Level Data RIIFS
Study MEW Area
86 DO/OO/OO (DOCU8ent. I'Ullbered out of 7
sequence)
87
12/24/86, lCent IC itch i ngIII8I'I
EPA Region 9
Alexis Strauss
EPA Region 9
Review of Analytical Data Re:
Mountain VieW Site utilizing
Organics Analysis
Att~ts
88
12/30/86
Wells RecOlhlle/1ded Sealed By
the C~ies as of 11121/86
Mountain View MEW Site
65
-------
REVISION DATE: 05/22/89
PACE: 9
Mlddlefleld-Elll.-Whi&88n Area SUperfund Site
Mcultaln VI..., California
- AdIIfnl.tratfw Record Index -
I
!!!!! FROI/ORGAN.I ZATI ON
01/02/87 . Robert WHlI-
Ecology .. Environ.nt, Inc.
TO/ORGAN I ZATI ON
DESCRIPTION/SUBJECT
Groundwater Sellpllng Audit
MEW Study Area
~
40
90 01/22/87 Eugenia Zorich EPA Region 9 Fourth Water Gulllity S~ling 150
.
. J811e8 McClure Round. Report R888dial Investi-
Harding Lewson Assoc. ptlon Fealbility Study
Mfddlefield-Ellis-Whisman Area
91 01/22/87 Harding Lawson Assoc. EPA Fourth Water GuIll ity S~l ing 360
Round Report Remedial Investi-
gation Feasibility Study
Middlefield-Ellis-Whisman Area
92 01/22/87 Terrence McManus Glem Kfstner Response to EPA' S COIIIIIef'It on 18
Intel EPA Region 9 Deten8ination of a Clean Well
Letter of 12/24/86
93 01/29187 Kent M. Kitchingman Alexis Strauss Review of Analytical Data 325
EPA Region 9 EPA Region 9 Gu8lityAaaurance Reports
1/6 through 1/29/87
Separ.te Att8dlalents
02101/87 Canonie Emfl"Cf'llental EPA Region 9 T echni clil Me80 DW6 Well 150
Cluster Installations MEW Area
Remedial Investigation
Feasibility Study
95 02/04/87 Glcenn Kistner C.R. Bostic Request for aound 3 Laboratory
EPA Region 9 Fairchild Data
96
02/05/87
Glcenn Kistner
EPA Region 9
Michael Rosa
Raytheon
Interi. Remedial Measures
9
97
02/06/87
C.R. Io8tic
Fal rchild
Glem Kistner
EPA Region 9
Mountain VI... RI/EAlFS
Sc:hedul es
2
98 02110/87 Kent Kitch i ngIIIIIr'I J8eII Grove . Review of ANlytfcel Data, 60
EPA Region 9 EPA Region 9 GulllIty A8aurence Reports
213/87 tttru 2/10/87
Sep8rate Report.
02/13/87 E.R. Bostic Glem Kistner Detailed Feasibility Study 4
Fairchild EPA Region 9 Analysis
-------
. .
REVISJON DATE: OS/22/89
.PAGE: 10
Middlefield-Ellis-Whi.-.n Are8 Superfund Site
Mcu\tain Vi.., California
... Adainistrative lecordlndex ...
~
100 .
2m
02/'23/81
FROM/ORGAJlI ZA T ION
Craig Von Bargen
CaIIp Dresser" MctCee Jnc.
TO/ORGANJZATION
Glenn Kistner
EPA Revion 9
DESCRIPTION/SUBJECT
Iwi.. of R8'(theon Jnterim
le88di al M888ure( s >
~...
3
101
fJ3/00/87
Golder Assoc.
R 8'(.theon
Jnteri. le88di.l Measures
Vol~- I
300
102
03/00/87
Golder Assoc.
Raytheon
Interi. Remedial Measures-
VolUlle II
1.00
103
03/02/87
C.I. Bostic
Fairchild
Glem Kistner
EPA Region 9
Tr8ftS8itt~l Siltec Area Water
Quality Data. Mountain View, CA
25
101. 03/05/87 C.R. Bostic Glenn Kistner AddenduII to Technical Memo: 250
Fairchild EPA Region 9 Short end Long tenD Aquifer
Tests Re88dial In¥eStigation
Feasibil ity MEW Study Area.
105 fJ3/11/87 Glenn Kistner C.R. Bostic Potenti.l Conduits Evaluation 8
EPA Revfon 9 Fairchild (-Decision Tree->
106 03/'23/87 SteYO DobrijeYic C.R. Bostic Status Report Fairchild 125
Phillip Ant0888ri. Fai rchild MotrItain View Facil i ty 4/1i86
Canonie Environnental through 12/31/86
Vol. J
101 03/'23/87 Stevo DobrijeYic C.R. Bostic Status Report Fairchild 300
Phillip Ant~rf. Fairchild MotrItain View Facil ity 4/1/86
Cananie Enviromental through 12/31/86
Vol. 2
108 fJ3/30/87 Glenn Kistner C.I. Bostic Request for ROI61ds 3.5 and 4 3
EPA Reiion 9 Fairchild Laboratory Data
109 04/00/87. Meredith Iol i r. Assoc. Expended PIP Search Mountain 300
View Site April 1987
Vol\88 J
110 01./00/87 Meredith Boli .. Assoc. Expended PIP Search 250
Mountain View Site
Apri I 1987
-------
REVISION DATE: OS/22/89
PAGE: 11
Middlefield-Ell is~\I'Ii8llin Area SUperl\ftt Sfte
Mountai" View, California.
- Acili"istratiw Record Index -
..
II
2m
04/02187
FROM/ORGANIZATION
Glem Kistner
EPA Region 9
TO/ORGANIZATION
C.R. Bostic
Fai rchlld
DESCRIPTION/SUBJECT
Saling of Potential Conduits
~
3
.
'112
04/08/87
Ted SIIith
. Sil icon Valley Toxics
Coalition .
Robert P. Stem
EPA Region 9
Mountain View Cleanup
2
'.
.,
113
04/10/87
Joshua R." FlOUI
Heller, Ehr88n, \I'Iite &
McAuliffe
lilem Kistner
EPA Region 9
four Ref. No. T-1-3
.2
, 114
I ,
I
04/13/87. Michael Kent
Citizens for a Better
En",i ronnent .
Rob Stem
EPA Region 9
Interim Clean up Proposal
bot Raytheon Ib.r'Itain View
2
115
04/13/87
C.R. Bostic
Fai rchild
Glem Kistner
EPA Region 9
Data Verification of Sample
ROU1ds
2
04/13/87 Joshua R. FlOUl Glem Kistner Raytheon Slurry WaU 2
Heller, Ehr88n, \I'Iite EPA Region 9
, McAul i ffe
117 05/12/87 Jeff Zeliltson Michael Rosa Interi. Remedial Measures 2
EPA Region 9 Raytheon
118 05/19/87 Jolitn Mastel'll8l'l Glem Kistner Trans.ittal Laboratory Data 3
Intel EPA Regi on 9 Val idation Water Quality Saq)-
ling Rounds 3.5 .. "
RifFS MEW Area
119 061as/87 Phillip FltZW8ter Raytheon Status Report: Water Qual fty 250
Lesl.. COnner _Water Lewl Oat" SUllMry
Hall'd;ng Lewson Assoc.
120 06/12/87 John Muter--. Glem Kistner Trans.fttal Selected Organic 200
Intel EPA Region 9 Ir Inorganic a._ieals
RI/FS MEW Area
06/26/87 Golder Assoc. Status Report Sol l Boring and 250
Monitoring Well Progr-
-------
REV.SION DHE: OS/22/89 PAGe: 12
Mfddleffeld-Ellis-WhfS88n.Area SUperfund Site
Mountafn Vfew, Celifornfa
-- Ad.fnfstratfw Record Index --
~ ~ . F1tCM/ORGANIZATION . TO/ORGAN I ZATION DESCRIPTION/SUBJECT ~
122 06/29/87 Jul i e Tumrou Intel, Reythean' Fairehfld Mou'ttain Vfew Well 18 MY18 30
Phillfp FftZW8ter Aquffier Teat MEV Study Area
Harding Lawson Assoc. Mou'ttain View, CA
Vol. I
123 06/29/87 Harding Lawson Assoc. Intel, Reytheon' Fairchild Mou'ttain View Well 18 (MY18) 400
Aqufffer Teat (MEV) Study Area
Mou'ttain View, CA
Vol. II
124 06/29/87 Anthony Burgess Glem Kistner Deep Sof l Investigation 365 20
Golder Assoc. EPA Region 9 East Middlefi led Road
Mountain Vrew, CA
125 06/30/87 James"'. Ol iver Glem Kistner Intel Soil Boring Data 2CO
Phillip Fitzwater EPARegion 9 . Mou'Itain View, CA
Harding Lawson Assoc.
126 07/00/87 Middlefield-Ellis-Whisman EPA Region 9 RI Vol. 1-3 '9 Docs &. Vol. 2- 2102
CQq)8ni es . 8 'Revisec:!" Materials in Record
(Vol. 4-8 Avail~ at M~~ View
Public, Lib. & EPA Region 9.)
127 07/21/87 Glem Kistner John Mastennen Additional Deep Monitoring 2
EPA RegionC) Intel Wells
128 07/21/87 Phillip Fitzwater Michael Rosa Transmittal of Final Phase III 225
Harding Lawson Assoc. Raytheon SUbsurface Investigation
Report
129 07/24/87 John Mastennen Glem Kistner Intel Response'to EPA 41
Intel EPA Region 9 6/11/87 c~ts on R...eIial
Investigatfon ,. '
I
130 08/04/87 John Mast.,..,.. Glem Kistner Additfonal Deep Monitoring 2
Intel EPA Regf on 9 Wells
131
08/04/87
Jeff Zelilcson
EPA Region 9
Dave Deardorf
Raytheon
Vapor Extraction WOrk
2
132
08/11/87
Kent Kftchingmlln
EPA Region 9
., Zi~er
EPA Region 9
Review of Analytical Data
2
-------
REVISlpN DATE: OS/22/89
-
!!lli
00/00/00
FROM/ORGANIZATION
Middlefield-Ellia-WhfS88ft Area Superfund Site
Mountafn Vi.., California
-- AdIIfnfatratiw Record 1r1dex -- .
TO/ORGANIZATION
DESCRIPTION/SUBJECT
Organic Chell;cal Anal ys;s
Methods .
PAGE: 13
~
2
-------
Page No.
12/29/88
Middlefield-Ellis-WhiS88n Are. SUperfund Site
Mcultain Vi..., Cal ifomia
ADMI.ISTIAnVE R£aJtD UDEX
SUppl~t No.1
DOC. ,
DATE
FRCIt/ORGAJI I ZAT 1011
TO/ORGAJlI ZA nOlI
DESCR I PT 1000/5W.IECT
PAGES
11/14/86 J8IIeS M. al iwr EPA Region 9 Technical Me8o: Fl"8nCia Well 85
JIIIeS G. McClure Tf- Series Test RI/FS
Hardi ng Lawson
Associates
2 03/02187 SteYO Dobrijevic C.R. Bostic Siltee Area water Quality Data 37
Canonie Fai rchild
£nvir~tal S-iconcb:tor Corp.
3 11/01/87 Canoni e on-Site Concentrations of. Metals 26
in GrCU'd Water
4 12/G4/87 Harding Lawson EPA. Occurrence of Anti~, Arsenic, 187
Cacbh.. and Lead in Publicly
SCIq)led water Supply Wells and
water Suppl y Systems, Santa
Clara County, CA. RI/FS
5 01/04/88 ICF - Clement CaIIp Ores.... & Endange,.."t Assessment (Draft) 228
MdCee, Inc. ,
6 01/08/88 C.R. Bostic Glenn R. Kistner Ltr: Ad8inistratiw Reeord for
Fairchild Corp. EPA Region 9 ReI)
7 01/27/88 Keith A. Takata C.R. Bostic Ltr: Use the Upper Aquifers (A & 3
EPA Region 9 Fai rchild B) in Mt. Vi...
8 02/00/88 Canon; e EPA Region 9 Report: Rezendes Well 23::-2 127
Pulping Test Fairchi ld Mt. View
foell i ty
9 02/04/88 Glenn R. Kistner C.R. Bostic Ltr re: Adaini.trative Record
EPA Reg; on 9 fai rchild for the Site
10 02/08/88 J8IeS Jasperse Raytheon Soi 1 Vapor Extrec:tion Study 260
D8Yid P. HodI8Ith
Harding L81180n
11 03/03/88 . ,Dennis L. CUrr8ft Glenn R. Kistner ltr: Monitoring Well Locations 4
Canoni e EPA Region 9 end Screen Intervals, Additional
-.,- Walls North of B8yshore
12 03/10/88 C.R. Bostic Glenn R. Kistner Report: Potential Conduits Study 71
fairchild EPA Region 9 end R-.diation BCU'dary
-------
Page No.
12/29/88
2
Middlefield-Ellis-Whi..-n Area SUperfund Site
. *"-,,tain View, Cal ifornia
ADMINISTRATIVE RECORD INDEX
SUpple.ent No.1
DOC. tI
DATE
FROM/ORGAN I ZA T ION
TO/ORGANIZATION
DESCRIPTION/SUBJECT
PAGES
13 03/11/88 Intel, Fairchild & EPA Region 9 $election of Metals of Concern 19
Raytheon
14 03/1'188. Intel, Fairchild' EPARegion 9. ec:..nts on the EndengeMllent 7
Raytheon Asses88ent
15 03/24/88 Eric G. L8JIP8la °lntel, Fai rchild & Ltr: COM Modeling for the RI/FS 7
Harding Lawson Raytheon
16 04/04/88 Eric G. Lappala Intel, Fairchild & ltr: 3/3/88 Meeting with CDM On 3
Harding Lawson Raytheon Model ing For the RI/FS
17 04/05/88 Glenn R. Kistner C.R. Bostic Ltr: EPA Review of the 7
EPA Region 9 Fairchi ld . hPotential Conduits Study and
Remedi at i on BClU'dary Report",
3/88
18 04/05/88 C.R. Bostic Glenn R. Kistner Ltr: Ca8puter Modeling .for. the 3
F.irchi ld EPA Region 9 site
19 04/06/88 J8EeS G. McClure C.R.Bastic ltr: ~ry of Activit.ies. for 2
Hardi ng Lawson Fai rchild 3/88
20 04/14/88 c.'Ioni e EPA Region 9 \later Clu8l ity Test Results 18
21 04/15/88 Dennis L. Curran c: Robert Bostic Ltr: Monthly Status Report 3/88
Canonie
22 04/25/88 Glenn R. Kistner George Gullage Ltr: Data Validation
EPA Region 9 Rayth~
23 04/27/88 John Maste,...;", Glenn R. Kistner Ltr: Response to Specific RI 4
Intel EPA Region 9 Report CcIInents by EPA
24 05/09/88 C.R. Bostic Roger B. J8118S Se8iannual Status Report: 180
Fai rchfld Regional Water Fairchild 7"'87 - 12~1'87
Quality Control
Board
. .
25 05/18/88 Glenn R. Kistner George Gull818 ltr: Response To C08Ip8I"Iies' 3
EPA Region 9 Reytheon Letter on Gr0U'dw8ter Model ing
26 OS/20/88 Chein Ping Keo Helen. MdCinley Ltr: StateARARS for the site 5
CDHS EPA Region 9
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;)age No.
12/29/88
3
Niddlefield-Ellis-WhiS88n Area Superfund Site
Mountain View, Cal ifomia
ADMINISTRATIVE RECCRD INDEX
SUpple.ent No- 1
DOC. ,
DATE
FIICI4/OtGAN I ZA T ION
TO/OtGANI ZATION
DESCRIPTION/SUBJECT
PAGES
27 06/14/88 Eric G- L8I'P8la Intel, Fairchild' Ltr: Require88nts for Additional "
Harding LIN8OI'I . Raytheon Infol'88tion to 'Adequately Review
GrOU'.:l-Water Flow and Transport
Modeling Perfor8ed by CDM
28 06/15/88 George A. Gull-.;e Glenn R. Kistner ' Ltr: RI Report - 6/15/88 3
Raytheon EPA Region 9 Revi.ion RIll'S
29 06/24/88 Dennis L. Curran C.R. Bostic Ltr: Infol'88tion Needed on CDM
Canonie FairchHd Silva Well Model
30 07/0'5/88 C.R. Bostic Glenn R. Kistner Ltr: COM Modeling Reports 2
Fai rchild EPA Region 9
31 01/11/88 George R. Gullage Glenn R. Kistner Ltr: Pre I iminary Responses to 13
Raytheon EPA Region 9, EPA Caa8ents on FS
32 08/08/88 Ph il Sobel Georve Gullage Ltr: Approvel Of 6/15188 RI 2
EPA .egion 9 Raytheon Report
33, 08/12/88 Glenn R. Kistner George Gullage Ltr: CaIIp Dresser and McKee's 3
EPA Region 9 Raytheon Grcudw8ter Model ing
34 09102188 ItF - Cle8ent CaIIp Dresser , Meteee Endange~ Asaesa8lent 215
35 10/12/88 C. R~ Bostic SteYen R. Ritchie Se.iannual Status Report: 123
Fai rcM ld Regional Water ' Fairchild 1/88 - 6/88
Quality Control
Board
36 10/21/88 CIIq) Dresser & McKee EPA Evaluation of Potential Conduits 22
in the Local Study Area
31 11/01/88 Glenn R. Kistner Guidance Docunents For 2
Administrative Record
38 11/01188 EPA Region 9 Fact Sheet: EPA Amo&n:es 10
Proposed Plan to Clean lJf) "-E-\I
, . SUperf&n:t Sites
39 11/01/88 Canoni. Fairchild, Intel' Draft Rpt: Feasibility Study, 1100
Raytheon N-E-\I Area, Nt. View, CA
-------
P9ge No.
12/29/88
DOC. II
40
I
I.
,
DATE
11/23/88
Middlefiel~Elli.-WhiS88n Are. Superfund Site
.....t.fn View, cal ffomi.
ADMINISTRATIVE RECCRD INDEX
5uA»l~t 110. 1
FROM/ORGAN I ZAT J ON
TO/ORGANIZATION
Phi l Bobel
&PA Region 9
Georve Gul hlte
. Raytheon
DESCRIPTJoN/SUBJECT
Ltr: Approw8l of Feeafbflity
St\ldv Report for "-E-W Area, "t.
Vfew, CA, with C8w8ta
PAGES
2
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."
Pa,e, No.
OS/Z5/89
Mfddleffeld-Ellfa-Whf..-n SUperfund Sfte
Mcu\tafn Vf.., Cal ffornfa
ADM I II I STRATIVE RECORD INDEX
Suppleaent 110. 2
DATE
DOC. ,
AUTHOR
RECIPIENT
DESCRIPTION/SUBJECT
PAGES
0.00 Guid8nce DOCUIenta for
Aalfnfatratfve Record
02/01/86 1.00 EPA-9 lIational priorities List (NPL) 28
Re8edfal Response Sfte Raytheon Corp., Mtn. View,
Prograni CA
02/01/86 2.00 EPA-9 National Priorities List (NPL) 2'
Remedial Response Site, Intel Corp., Ntn. View, CA
P!"ogr-
02/01/86 3.00 EPA-9 National priorities List (NPL) 10
Remedial Response Site Fairchild Canera ..
Progr. Instrullel'lt Corp., Ntn. View, CA
05/01/86 4.00 '- EPA-9 Erwiror8lntal News: New 2
Cont.inationFound in Ntn.
Vfew's Deep ~ifer. w/lII8p.
i1/01/86 5.00 Michael Kent Robert Stem ~ta on Fairchild 3
Research Asaoc. EPA COIIIU'Ii ty Se8fconductor Interi. Remedial
Chizens for a Relations Action Proposal.
Better Erwironment Coordinator EPA-9
07/21/86 6.00 Cltet Lauchner Glenn Kistner CaaBents on -Interi. Remedial 3
Director - EPA-9 Actions, Farichild Semiconductor
Facilities Planning, Corporation, Ntn. View Facility
Int'l Ops., Siltec - Draft Report by Canonie 6/86
Corp
07/2B/86 1.00 Ted SIIith Robert Stem C~ts on Fairchild 2
Executfve Dfrector EPA ec-.nf ty S.iconr:U:tor Interi. Clelft4)
Sil icon Valley Relations
Toxics Coalition Coordfnator EPA-9
08/22/86 "8.00 , Harry Seraydarian Chet lauchner ltr: Response to 1/21 .. 08/01/86 2
EPA Region 9 Siltec Ltr. about Fairchild Slurry Wall
10/01/86 8.10 COM Soil ~lfng ," Tank Inventory 153
Data Co.pilatfon.
01/09/88 8.90 0 f erne MctCenna Glenn Kistner Ltr: COIIIIIent on the Clean-!4)
Santa Clara, Board EPA Revi on 9 Plan
of SUpervisor
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Page No.
05/25/89
Middlefield-EllU-Whisman Superfund Site
Mountain View. California
ADMINISTRATIVE RECORD INDEX
Supplement No. 2
DATE
DOC. i
AUTHOR
RECIPIENT
DESCRIPTION/SUBJECT
PAGES
•02/04/88
9.00 C. Robert Bostic
Glenn R. Kistner
EPA Region 9
Interim Decision Process
Potential Conduits Evaluation
Rpt with cover letter
06/01/88 10.00 Lorance D. Wilson
Santa Clara Valley
Water District
Glenn R. Kistner
EPA Region 9
Ltr: Closure of Franz ia ft Silva
Wells
06/15/88
11.00
Glem Kistner
RPM
EPA-9
George Collage
Proj. Coordinator
Ratheon Co.
General Coments on Draft FS for
MEW Study Area, w/TL to George
Gullage 6/15/88
06/22/88 12.00 Roger B Janes Philip Bobel
Executive Officer EPA-9
CRWQCB-SF
Coments on the MEW Feasibility
Study by Canonie 5/3/88
06/24/88
13.00
Glenn Kistner
RPM
EPA-9
George Gullage
Proj. Coordinator,
MEW Study Area,
Raytheon Company
EPA Cements On The MEW
Feasibility Study W/TL to George
Gullage 7/24/88
10
06/28/88
09/00/88
14.00 NEC Electronics,
Inc.
15.00 Geraghty ft Miller
Technical Review Coments 21
Remedial Investigation Report
RI/FS MEW Area, Ntn. View CA
w/LTR to Glem Kistner 6/28/88.
w/charts ft naps.
Intel RI/EA/FS Vol. 1-4 with 2000
cover letter
09/14/88 16.00 George A. Gullage Glem Kistner
Raytheon EPA Region 9
Ltr: Cements on Final Draft
Endangement Assessment
09/15/88 17.00 Rick Robison Glem Kistner
Reg. 2 - Toxic RPM
.Substances Control EPA-9
Oivison
CAOOHS
CAOOHS Coments on MEW Draft FS
Report 8/16/88 Revision
10/00/88
10/13/88
18.00
Canohie
19.00 George A. Gullage
Raytheon
Mark Harris
City of Mt. View
Rpt: Sampling Plan Addendum No.
2 Walker Drive Investigation
RI/FS
Ltr: A sumary of MV18 "8" and
•Deep" Aquifer Monitoring
Activities with a Distribution
List
-------
P8ge No.
05/25/89
3
Mlddlefield-EllIs-WhI..-n SUper1und Site
Mo&.m:aln YI..., California
ADM I II I STRATIVE RECORD INDEX
SUpple8ll'lt 110. 2
DATE
DOC. tI
AUTHOR
RECIPIENT
DESCRI PTIONISUBJECT
PAGES
10/13/88 20.00 Glem Kistner George A. Gullage Covet" Ltr of S81pl i". Plan 2
EPA Region 9 Raytheon ~ No.. 2 with 8
Distribution List
10/19/88 21.00 Stew Morse Glem Kistner Ltr: Draft FS, 10/01/88 Revision 2
CRWOCB EPA Region 9
10/21/88 21.10 CDM Evaluation of Potenti al Condui ts 34
in the Local Study Area, MEW
(Update of 5/9/88 Document).
10123/88 22.00 Terrence J. McManus Phil ip Sobel Ltr: Request to Comment on
Intel EPA Region 9 RI/EA/FS & Sign Sep8rate ROO
10/25/88 23.00 Bryan M. Rector Glem Kistner Intel Mt. View Ground Water Data 850
EPA Region 9 Base Rpt. FrOll 10/86 . 1188
attached with Lab Analytical
Rpts, CoYer letter, Airbill,
Tr8nS8ittal Letter
11/00/88 24.00 EPA P\bl ie Feet Sheet
11/10/88 25.00 Glem R. Kistner George Gullage Ltr: Approval of Sampling Plan 2
EPA Region 9 Raytheon Addendua No.2 Walker Drive
Investigation RI/FS But Not of
Objective of the Plan
11121188 26.00 C. Robert Bostic Phil ip Sobel Ltr: Intel's Rl/EA/FS for Lot #3 2
Sch ll.lllberger EPA Region 9 Ir Concern about Seper8te ROO
11/23/88 21.00 Ph il Bobel Georve Gull age Ltr: Approval of Revised FS 2
EPA Region 9 R8'fthean \nMr 5 Caveats
11/25/88 28.00 Glem Kistner Glem Stober Ltr: CoYer Ltr of FS for Comment 2
EPA Region 9 CA Office of
PlaMI". .. Research
12/01/88 29.00 George Gullege Glem Kistner Ltr: Confinl8tlon of the 2
Raytheon EPA Region 9 Sailpl int Plan Adclendul 110. 2
walker Drive Investigation,
RI/FS, with a Distribution List
12/02/88 30.00 G1em R. Kistner George Gullage Ltr: Reuse of Groundwater 1 .
EPA Region" 9 Raytheon
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Page No.
rY5/25/89
,
Middlefield-£llls-Whl..-n SUperfund Site
Mcurt81n YI..., Callforni8
ADMINISTRATIVE RECORD IIIDEI
s.wl--.t 10. 2
DATE
DOC. .
AUTHOR
RECIPIENT
D£SCRIPTIOI/~ECT
PAGES
12/f19/88 31.00 Gordon C. Atkinson . Devid McF8dden Ltr: Intel's RIIEA/FS Lot 13 & 2
Cooley Godwerd EPA Region 9 Separate RCD
Caatro Huddleaon &
TatUl
12/1'/88 32.00 SUsan N f sbet ec-utfty Meeting 81
Cr.-.gle & Asan.
1211'/88 33.00 Leura T. Tarquinio Glem Kistner. Ltr: ~t on the. Proposed 2
League of WOllen EPA Region 9 Cle8nUp Plan
Voters
12/14/88 34.00 Mfchele.B. Corash. ., Zilllpfer Ltr: lequest Extension of 4
Morrison & Foerster EPA Region 9 CoI8nt Period on Dr:aft FS
12/21/88 35.00 .". Water .Elevation Rpt. 52
01/04/89 36.00 Gordon F. snow. Glem Kistner Ltr: State has no C088entS on FS
... EPA Region 9
Thelesources Agency
of CA
01/04/89 37.00 George A. Gullege Glem I. Kistner SlJ:8iUal of Tedlnicel Iep)rt on 28
Raytheon EPA Region 9 Extracted Groundwater Use
" 01/09/89 38.00 Margaret R. Dollbaua Glem Kistner Ltr: Litronix Needs More Time to .
Folgor & Levin EPA Region 9 Review Draft FS
01/10/89 40.00 George A. Gullage Glem R. Kistner Ltr: Propose Interi. Remedial 2
Raytheon EPA legion 9 Actions of OW-3 Cluster and
Packing of Silv. Well
01/17/89 41.00 Ph fl 8Clbel Terrence J. MdC8rA8 Ltr: Co88ents on II/FS/IA for 2
EPA legi on 9 Intel Intel Lot 13
01/17/89 42.00 Ph fl Sobel Georve Gullege Ltr: Authorization to wort on RA
EPA Regi on 9 R8Ytheon at the OW-3 Well Cluster &
PUlping and Treat8ent of
Grou1dw8ter.
01/18/89 43.00 Sandy Oll I ges Glem Kistner. Ltr: On Behalf of MA$A-A8es to 2
A8es lesearch Center EPA Region 9 CC8MI'It on FS
01/20/89 44.00 David C. Keehn Glem Kistner Ltr: eo..ents on Draft FS and 3
. A I r Products EPA Region 9 Propose Selection of le88dy for
the Sfte
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:"'.
Pege NO.
(15/25/89
5
Mlddlefleld-EllIs-WhI.-.n SUperfund Site
Mountain VI_. Callfomla
ADMINISTRATIVE REaIID INDEX
~l~t 10. 2
DATE
DOC. ,
AUTHOR
RECIPIENT
DESCRIPTION/SUBJECT
PAGES
01/20/89 45.00 St..l y T. Meyers Glenn Kfstner Ltr: ec-nt on RI (06/88) , 17
Sfltec EPA Region 9 Draft FS (11/88) end Propose
Cleanup R888dy for the Site
01/20/89 46.00 Jeff~ J. Lede...... Glenn Kistner Ltr: eo..ents of Reneult , 3
Were' Freiederich EPA Region 9 Hendley Group on Draft FS
01/23/89 47.00 ThC18S E. Hooitam Glenn Kistner Ltr: C~t on FS of Cleanup 7
Crosby. Heafey. EPA Region 9 Alternative on Behalf of
Roach , May Sobratoto
01/23/89 foB. 00 SteYen R. Ritchie Glenn Kistner Ltr: cc..nt on Proposed Cleanup 2
CRwQCS-Sf EPA Region 9 Plan
01/23/89 49.00 Robert C. Thompson Glenn Kistner Ltr: Comments of Tri-Data on 3
Grah8l!l ,- J8IIII!S EPA Region 9 Draft FS
01/23/89 50.00 Jonathen S. Leo Glenn Kistner Ltr: eo..ent8 of NEC Electronics 13
Heller. Ehl'll8n. EPA Region 9 on Draft fS Attached with
White' McAuliffe Technicel Review CoIIInents
01/23/89 51.00 Cari e Gooci8n Glenn Kistner - Ltr: Request RI/FS/EA (10/23/88)
1
McK i nney EPA Region 9 to be Included in A.R.
McCutchen, Doyle,
Brown' Enersen
01/23189 52.00 Robert S. Rosborough Glenn Kistner Comments of Spectra-Physics on 2
Pill stlury. Madi son , EPA Region 9 Draft fS
SUtro
01/23/89 53.00 Bart D. Denua Glenn Kistner Ltr: eo..ent on Oraft FS And 3
Trscor EPA Region 9 Object Arty Responslbfl ity to
Pollute the Site
01/23/89 54.00 Loui.. T. Lew Glenn KI~tner eo..ents on Draft FS Attached 8
U S Dept. of Navy EPA Region 9 wi th Cover Ltr.
01/24/89 55.00 Roger B. J... Glenn Kistner Ltr: ec-ent on Proposed Plan 3
Sent a Clara Valley EPA Region 9 Attached with Rec: l.de
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.--------- -
-,
Pege' No.
(15/'15/89
6
Middtefietd-Etti.-Whi.-.n SUperfund Site
Mcuttain Vi..., C8t ifornia
AlMUIISTUTlW RECORD INDEX
~t---t 10. 2
DATE
DOC. ,
AllTHCI
IECIPIENT
DESCRIPTIOI/SUIJECT
PAGES
01/30/89 51.00 Gtenn R. Kistner M8rk I18rr i s Ltr: Penli..ion to Seal the City
EPA Region 9 CitY of Nt. View Parle and Recreation Well
01131/89 58.00 Georve A. Gul t ege Gtenn Kfatner GrO&niwater Level Noni tor;ng-C 19
R8Ytheon EPA Region 9 Aquifer and Water Quality Result
- Silva well Cluster Atteched
Cover Letter
02/01/89 59.00 Ph it Sobel George Gullage Ltr: Notice of Sealing Wells and
EPA Region 9 Raytheon L i abil i ty tor the Cos t
02/22/89 60.00 PhH ip Sobel Terry McMaru; Intel Caa8ents on MEW FS. 2
Chief-Remedial Sr. Mgr-eorporate
~rfund Prog. Envil'ONlental
EPA-9 Affairs, Intel Corp.
- .
03/02/89 61.00 George Gullege Dfatribution Public eo..ents on MEW Area FS 1
Proj..Coordinator REport wlTL to Gtenn Ki stner
R8Ytheon Co. 3/2/89 .
03/06/89 62.00 EPA,.9 Envi~tat 1Iew8: EPA Plans to
seal two NHr-by wells, (2)
03/15/89 63.00 George Gullage Glenn Kistner C0888ntS RE: Philp bobel's 2
Proj. Coordinator EPA-9 letter of 2/1/89
Raytheon Co.
03/21/89 64.00 George Gullege Distribution Public eo..ents on the MEW Area 4
Proj. Coordhwtor FS Report W/TL to Glenn Kistner
R8Ytheon Co. 3/21/89.
04/12/89 65.00 Canoni e George Gullege Rpt: Walker Drive IlW88tigation 46
Proj. Coordinator RI/FS MEV Study Area Mtn. View,
R8ytheon Co. CA
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Page No.
00!I/12/89
DATE
04/25/89
-- Total --
DOC.'
AUTHOR
o
1 Bay Area Air Quality
Manage8ent District
o
Middlefield-Ellis-WhiS88n SUperfund Site
Mcu1tain View, Califomia
ADMIIISTRATIVE RECCItO INDEX
~l...t 110. 3
RECIPIENT
interested perties
DESCRIPTION/SUBJECT
Toxic Air Pollutant Source
Assessaw:nt Merull for
California Air Pollution
Control Districts (.~
guid8nce") August 1987.
Workshop Notice: Proposed
Regulation 8, Rule 46. Air
Stripping & Soil Vapor
ExtrICtion Operation.
PAGES
50
3
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