HomeMy WebLinkAboutAttach 1 Appendix COctober 1, 1997
Job No. 1394.904
BGC
BERLOGAR
GEOTECHNICAL
CONSULTANTS
Ms Jennifer Lin
% Mr. Ted Fairfield
5510 Sunol Boulevard
Pleasanton, California
94566
Subject:
Phases 1 and 2 - Environmental Site Assessment
Pao-Yeh Lin Property
Tassajara Road
Dublin, California
Gentlemen:
INTRODUCTION
This report contains the results of our Phases 1 and 2 - Environmental Site Assessment of
hazardous and toxic substances for the subject project. The site is located north of Interstate 580
and east of Tassajara Road in Dublin, California. The location of the property is shown on the
Vicinity Map, Plate 1.
Purpose
To identify and assess characteristics of the subject property that may have been contaminated
based on current or historic uses a Phase 1 - Environmental Site Assessment was performed.
Also, based on previous agricultural use of the site, a limited Phase 2 assessment was performed
which included: soil sampling and analytical testing to evaluate the presence and/or concentration
of pesticides or herbicides in surface soils. For the purpose of this assessment, hazardous
contaminants are defined as those substances listed as hazardous per Title 22 of the California
Code of Regulations (CCR).
SCOPE OF WORK
Our scope of services for this study have included:
A site reconnaissance including photographic documentation, observations of surrounding
properties, and site vicinity;
2. Interviewing current and previous land users;
3. Contacting pertinent government agencies to obtain relevant information;
SOIL ENGINEERS · ENGINEERING GEOLOGISTS · 5587 SUNOL BOULEVARD · PLEASANTON, CA 94566 · (925) 484-0220 · FAX: (925) 846-9645
October 1, 1997
Job No. 1394.904
Page 2
Review of available information pertaining to site history, land uses, and geologic maps
of the site vicinity;
Examination of several generations of stereopaired aerial photographs;
Assembling and interpreting data;
Obtaining twenty-seven surface soil samples and performing analytical testing on five
composite samples for presence of pesticides (EPA 8140) and herbicides (EPA 8150);
and
Preparation of this report presenting our findings and opinions.
PHASE 1 - ENVIRONMENTAL SITE ASSESSMENT
Site Description
The site is a rectangular shaped parcel encompassing about 300 acres, as shown on the Sample
Location Map, Plate 2. The Assessors Parcel Numbers (APN) are 985-0005-001 and 985-0005-
002.
The subject property is currently undeveloped. The southern half is relatively fiat having
elevations ranging from about 340 to 350 feet, sloping to the south. This area has been recently
disced and is currently used for agricultural purposes. The northern half of the site consists of
rolling hills and intervening valleys that rise from elevations of 450 to 500 feet with drainage
towards the south currently used for grazing. There is an existing stock pond located along a
valley in the north-central portion of the site.
Site History
Information on the history of the site was obtained by a review of a preliminary title report by
First American Title Guaranty Company, dated June 26, 1997, an examination of several
generations of aerial photographs of the site and surrounding area, and interview and discussions
with Mr. Clyde Casterson (who has reportedly managed the property for about 40 years). Mr.
Casterson currently leases the site for ranching.
Reportedly, the site consists of two parcels (designated as Parcels 1 and 2). Records indicate
that the property was a portion of lands of Rancho Santa Rita prior to 1862. The property was
owned by Samuel Martin and acquired by Michael and Thomas Devaney between 1862 and
1880. Pao-Yeh Lin and Bih-Yu Lin acquired the lands in 1977 and are the current owners.
Aerial photographs taken in 1957 show five small structures and corrals clustered near the north
of drainage swale which discharges to the flatland area in the central portion of the site. The
BERLOGAR GEOTECHNICAL CONSULTANTS
October 1, 1997
Job No. 1394.904
Page 3
1957 photographs show the remainder of the site appears to be undeveloped vacant lands. Aerial
photographs taken in 1969, 1976, and 1986, show the site appears to have remained relatively
unchanged from the 1957 photographs. Photographs taken in 1996 show all pre-existing
structures had been completely removed; the remainder of the site appears relatively unchanged
from the earlier 1986 photographs.
According to Mr. Clyde Casterson, based on his knowledge, the property has been used
exclusively for farming and grazing purposes over about the past 40 years, and that the previous
structures and corrals at the site were vacant since circa 1940. Mr. Casterson has indicated that
to iris knowledge, no underground storage ta~ks or asbestos containing materials were located
at the site.
Site Survey
On July 25, 1997, Mr. Theodore Bayham of Berlogar Geotechnical Consultants (BGC) visited
the site, toured the grounds, observed conditions at the existing site and surrounding properties.
During our site visit, the site was apparently used for agricultural on the southern half and
grazing on the northern half. The southern half of the property was plowed but not planted.
About 500 feet south of a stock pond near the center of the site, some minor wood rubble and
existing fill was noted that appears to be remnant debris from the previous structures. An old
well casing was observed in this area. No underground storage tanks (USTs) were observed at
the site, and no apparent staining of surface soils in this area was noted. No barrels or
suspicious materials were observed at the site..
Surrounding Land Use
The surrounding area to the west, east and north is currently undeveloped and also used for
farming and ranching purposes. The site is bounded by a frontage road and Interstate 580 to
the south.
REPORTS BY REGULATORY AGENCIES
A review was made of relevant public records concerning the subject property. Primary sources
of information consulted include:
1. Alameda County Department of Environmental Health;
2. Dublin Fire Department; and
3. Environmental Data Resources, Inc. - Radius Map with Geocheck.
BERLOGAR GEOTECHNICAL CONSULTANTS
October 1, 1997
Job No. 1394.904
Page 4
Interviews with Alameda County Department of Environmental Health and Dublin Fire
Department personnel report no known hazardous materials stored or used at the site, or
underground storage tanks.
The site is not on the EPA National Priorities List, the California DOHS Bond Expenditure List,
nor lists of underground tank leaks or hazardous sites kept by RWQCB of the County or City
agencies. It is also not posted on the Comprehensive Environmental Response Compensation
Liability and Information System (CERCLIS). The site is not on the Resource Research and
Recovery Act (RCRA) listing as a hazardous waste transporter or generator. There are no sites
on the EPA National Priority List, the DOSD Bond Expenditure List, the SFBRWQCB North
Bay Toxic List within 1-mile of the subject site. The environmental data resources radius map
with geocheck is provided in the attached appendix.
The California Leaking Underground Storage Tank Report (LUST) repons no underground tank
leaks within a 1-mile radius of the subject site.
HYDROGEOLOGIC SETTING
Published maps of the site vicinity (Dibblee, 1980) show the area to be underlain by Plio-
Pleistocene sedimentary rocks of the Tassajara Formation in the northern, hilly part of the site
and Pleistocene-Holocene Age alluvium in the near-level southern part of the site. The Tassajara
Formation consists of interbedded siltstone, sandstone, and conglomerate and the alluvium
consists of interbedded sand, silt, clay and clayey gravel. The Tassajara Formation unit has
been mapped dipping to the south-southwest.
Concurrent with this Phase 1 and 2 study, BGC has performed field exploration for a
geotechnical investigation at this site. Ground water was encountered in a boring drilled by
BGC in the alluvium in the southern part of the site at an approximate depth of 31 feet. Also,
at borings in the northern part of the site, encountered ground water in the valley areas at about
10 feet below the ground surface. The grdund water gradient at the site likely follows the
general topographic gradient towards the south.
The findings of our Phase 1 study are summarized below:
1. Historic use of the site appears to have been limited to farming and ranching.
Records indicate that no known contamination or source of contamination exists at the
site.
No known ground water contaminated sites are located within 1-mile upgradient of the
site.
BERLOGAR GEOTECHNICAL CONSULTANTS
October 1, 1997
Job No. 1394.904
Page 5
No underground storage tanks or asbestos containing materials are known to exist at this
site.
PHASE 2 - LIMITED SOIL SAMPLING AND ANALYTICAL TESTING
Sample Collection
A total of 27 soil samples were collected on August 1 and 4, 1997 at the approximate locations
are shown on the Sample Location Map, Plate 2. These sampling locations are designated as
S-1 through S-27. Samples were obtained from the upper foot of soil, placed in unused glass
jars, and transported to our office. The 27 soil samples obtained were composited into a total
of five composite samples for analytical testing. The composite included: C-1 (S-i, S-2, S-3,
S-4 and S-5); C-2- (S-6, S-7, S-8, S-9, S-10 and S-il); C-3 - (S-12, S-13, S-14, S-15, S-16 and
S-17); C-4 - (S-18, S-19, S-20, S-21 and S-22); and C-5 - (S-23, S-24, S-25, S-26 and S-27)
The composite samples were transported under property chain-of-custody on ice to American
Environmental Network, Inc. (AEN) in Walnut Creek, California. Composite samples were
analyzed for chlorinated herbicides (EPA 8150) and organochlorine pesticides (EPA 8140). The
results of analytical testing by AEN on August 26, 1997 is included in the attached Appendix.
All five composite samples were found to have no detectable levels of chlorinated herbicides and
organochlorine pesticides.
Findings
The general composition of the topsoil at the sampling locations consisted of dark brown silty
clay. No obviously potential hazardous materials were observed during sampling, and no
detectable levels of pesticide or herbicide contamination were encountered.
CONCLUSIONS
On the basis of our Phases 1 and 2 - Environmental Site Assessment we did not find any
indication or conditions that would require a further Phase 2 study.
LIMITATIONS
Our environmental site assessment is based on a review of geologic maps and literature,
examination of aerial photographs, limited analytical testing and surface reconnaissance. Site
descriptions described in the text are those existing at the time of our field reconnaissance in
August, 1997, and are not necessarily representative of such conditions at other locations and
times. The conclusions and recommendations contained herein are professional opinions derived
BERLOGAR GEOTECHNICAL CONSULTANTS
October 1, 1997
Job No. 1394.904
Page 6
in accordance with current standards of environmental assessment practice; no other warranty
is expressed or implied.
Respectfully submitted,
BERLOGAR GEOTECHNICAL CONSULTANTS
Senior Engineer
88
Attachments:
References
Plate 1 - Vicinity Map
Plate 2 - Sample Location Map
Appendix A - EDR Radius Map with Geocheck
Appendix B - American Environmental Network, Inc. - Analytical Testing Results
Copies:
Addressee (6)
Mr. Dave Schneider (1)
MacKay & Somps (2)
Attention: Mr. Dave Chadbourne
wp51/report/5337
BERLOGAR GEOTECHNICAL CONSULTANTS
REFERENCES
Alameda County Department of Environmental Health Services, file review and personal
communication on August 26, 1997.
American Environmental Network, Inc., laboratory report dated August 26, 1997.
Berlogar Geotechnical Consultants, on-going geotechnical investigation and field exploration,
August 1997.
Casterson, Clyde, phone conversation on August 5, 1997.
Dibblee, T.W., 1980, "Preliminary Geologic Map of the Dublin Quadrangle, Alameda and
Contra Costa Counties, California", United States Geological Survey Open-File Report
80-537.
Dublin Fire Department, file review and personal communication on August 29, 1997.
EDR - Radius Map with Geocheck report, "Pao-Yeh/Lin Property", Inquiry No. 187728.1s,
dated August 4, 1997.
First American Title Guaranty Company, "Title Report Order 592434", dated June 26, 1997.
AERIAL PHOTOGRAPHS
Pacific Aerial Surveys: (August 5, 1997)
May 16, 1957, AV-253, Line 27, Frames 41, 42
May 15, 1969, AV-903, Line 5, Frames 18, 19
May 26, 1976, AV-1250, Line 05, Frames 15, 16
April 20, 1986, AV-2862, Line 5, Frames 18, 19
August 9, 1996, AV-5200, Line 28, Frames 37, 38, 39
BERLOGAR GEOTECHNICAL CONSULTANTS
I
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SCALE: 1"= 2000'
VICINITY MAP
PAO-YEH/LI N PROPERTY
TASSAJARA ROAD
DUBLIN, CALIFORNIA
FOR
MS JENNIFER LIN
SASE: PORTIONS OF USGS 7-1/2 MINUTE TOPOGRAPHIC QUADRANGLE
UVERMORE, CALIFORNIA. PHOTOREVISED 1980, AT A SCALE OF
1:24,000,
P~TE1
BERLOGAR GEOTECHNICAL CONSULTANTS
JOB NUMBER:1394.904 DA,C: 8-14-97 BY: PB
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