HomeMy WebLinkAboutPhase I and Phase II Environmental Assessment ExcerptsSITE ASSESSMENT REPORT
Forrest Property
265 Meissner Lane
APN 076-351-003
San Luis Obispo County, California
March 20, 2001
Project No. 792-A
PREPARED FOR:
Central Coast Group
Unocal Corporation
276 Tank Farm Road
P.O. Box 1069
San Luis Obispo, California 93406
PREPARED BY:
England Geosystem, Inc.
15375 Barranca Parkway, Suite F-106
Irvine, California 92618
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SITE ASSESSMENT REPORT
Page i
Forrest Property March 20, 2001
San Luis Obispo County, Califomia
TABLE OF CONTENTS
LISTOF TABLES...........................................................
LISTS OF FIGURES AND APPENDICES ....................................... ur
EXECUTIVE SUMMARY ................................................... ES-1
1.0 INTRODUCTION...................................................... I
2.0 ENVIRONMENTAL SETTING .......................... . ............... 1
2.1 Site Location and Description ........................................ 1
1' 2.2 Geology and'Hydrogeology..........................................2
HISTORICAL SITE CONDITIONS ..................... . ............. . ... 2
3.1
Historic Photographs...............................................2
3.2
Sanborn Fire Insurance Maps .........................................
4
3.3
United States Geological Survey Topographic Maps ......................
4
3.4
Chain-of-Title....................................................5
3.5
County Department of Planning and Building ............................
5
3.6
San Luis Obispo Tank Farm
• • 5
3.7
Environmental Records Review ......................................
7
3.7.1 County of San Luis Obispo Division of Environmental Health
........ 7
3.7.2 California Regional Water Quality Control Board - Central Coast Region
.....................................................:....7
3.7.3 Environmental Database Information ... ......... ....:...........
8
3.8
Phase I Assessment - Conclusions ....................................
10
PHASE
II ASSESSMENT ...............................................
11
4.1
Refine Delineation of Tank Farm Road Pipeline Release Plume ............
11
4.1.1 Drilline and Sampling Protocols ...............................
12
4.2
Assessment of Surface Impacts from the 1926 Fire .......................
12
4.3
Investigation of Perimeter Bordering Former Tank Farm ..................
12
4.4
Other Areas of Concern ............................................
13
4.5
Additional Monitoring Well ........................................
13
4.6
Survey.........................................................14
4.7
Irrigation Well...................................................14
TESTING PROGRAM ...... 15
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Forrest Property -
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San Luis Obispo County, California
March 20 2001
6.0 FINDINGS OF FIELD INVESTIGATION .................................
15
7.0 RESULTS OF LABORATORY ANALYSES ..................
I ............. 16
7.1 Petroleum Hydrocarbons ...........................................
16
7.2 Metals..........................................................
16
7.3 Volatile Organic Compounds ............ .........:...........
...... 17
7.4 Chlorinated Herbicides, Pesticides and Semi -Volatile Organic Compounds ... 17
7.5 Ground Water Quality .............................................
18
7.6 Phase II Conclusions..............................................18
8.0 REFERENCES........................................................
19
FIGURES, TABLES AND APPENDICES
Table No.
1
2
3
4
5
6
7
LIST OF TABLES
Title
Summary of ASTM Database Search
Summary of TPH and BTEX Concentrations in Soil Borings
Summary of Metals Concentrations in Soil Borings
Summary of VOC Concentrations in Soil Borings
Summary of Metals Concentrations in Shallow Soil Samples
Summary of Chlorinated Herbicide Concentrations in Shallow Soil Samples
Summary of Chlorinated Pesticides and Semi-VOCs in Shallow Soil Samples
E 1140 L ]NN D
Forrest Property
San Luis Obispo
Fieure
1
2
3
4
5
6
Appendix
A
B
C
D
E
F
SITE ASSESSMENT REPORT
an
LISTS OF FIGURES AND APPENDI.CES
LIST OF FIGURES
Title
Site Location Map
Site Plan
Site Plan Showing Sampling Locations
Cross Section A -A'
Cross Section B-B'
Cross Section C-C'
LIST OF APPENDICES
Contents
Historic Aerial Photographs and Topographic Maps
Environmental Data Resources Database Search Report
Boring Logs
Monitoring Well Development and Sampling Forms
Surveyor's Report
Analytical Laboratory Reports
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EXECUTIVE SUMMARY
Forrest P
San Luis
EXECUTIVE SUMMARY
Page ES-1
This report presents the results of Phase I and Phase II site assessments performed for the Forrest
property (APN 076-351-003). The subject site is a 20-acre agricultural property located on the north
side of Tank Farm Road immediately west of Unocal's former tank farm in San Luis Obispo,
California. Meissner Lane and Tank Farm Road form the parcel's northern and southern boundaries,
respectively. To the west is another agricultural parcel that is currently under cultivation. Several
structures occupy the northwest comer of the site (Figure 2). These include a small house, an
outhouse, a larger storage shed and a smaller shed. With the exception of the small corner of the site
occupied by structures, the property is kept under cultivation. A variety of crops are grown on the
property including squash, garlic, corn, beans, peppers, and tomatoes.
The objectives of the work described herein are:
1) to determine whether current or previous land use at or adjacent to the subject property may
have resulted in the release of hazardous substances or petroleum to the environment, and,
2) to delineate the on -site extent of petroleum hydrocarbons associated with the Tank Farm Road
pipeline release.
To address these objectives, the following scope of work was performed:
1) a Phase I assessment of the property in accordance with ASTM Standards (E1527-97) to
identify areas of potential concern related to historical site uses;
2) a Phase II assessment (i.e., soil sampling and analytical testing) of areas of potential concern,
including areas bordering the former tank farm and areas subject to surface releases resulting
from the 1926 fire; and
3) drilling, soil sampling, and analytical testing to refine (to 100 mg/kg) the delineation of
petroleum in soil associated with the Tank Farm Road pipeline release.
The results of the Phase I assessment indicate that the subject property has likely been used for
agricultural purposes since before the turn of the 19t° century. Sometime between the late 1890s and
1910, a private residence and several agricultural buildings were constructed near the northwest corner
of the property. In 1910, Union Oil Company of California constructed a large crude oil tank farm and
pump station east of the property and pipelines along the south border of the property. In 1926, a
lightening -sparked fire at the tank farm resulted in a release of petroleum that flowed over the
southeast comer of the Forrest property. In the late, 1980s, crude oil, released from a pipeline
underlying Tank Farm Road, was discovered beneath several properties bordering the road including
the Forrest property. In the early 1990s, subsurface investigations of a BTEX' occurrence in the
'BTEX denotes the aromatic hydrocarbons benzene, toluene. ethyl benzene and the isomers of xylene.
t-
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EXECUTIVE SUMMARY
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Sari Luis Obispo California March 20, 2001
offices area of the tank farm indicated that ground water containing elevated concentrations of
dissolved purgeable (C4 C,o) hydrocarbons and BTEX might extend beneath the southeast comer of
the Forrest property.
A search of federal and state environmental agency databases identified one other site, Promega
Biosciences, Inc. (formerly JBL Scientific)'-, with the potential to impact the subject property. Files
pertaining to the Promega/JBL property, which borders the Forrest property on the north, were
reviewed at the offices of the RWQCB in San Luis Obispo on February 22, 2001. This review
revealed that the property has been occupied since 1987 by a biomedical research, development, and
manufacturing facility that uses hazardous chemicals in its production processes and produces
hazardous wastes (Earth Systems, 1994). Three soil and ground water investigations have identified
concentrations of volatile organic compounds (VOCs), notably toluene, xylenes, tetrachloroethene
(PCE) and chloroform, in soil and shallow ground water. Historically, chloroform and PCE have
been detected in on -site water samples at concentrations of up to 190 and 22 µg/L, respectively.
More recent concentrations have been much lower. In general, the impact to water quality is limited
to the Promega/JBL property. RWQCB correspondence dated October 2000 indicated that if low
VOC concentrations are repeated in future monitoring events, then they would consider conditional
closure.
To determine whether releases of chlorinated VOCs on the adjacent Promega/JBL property have
impacted water quality, the irrigation well located in the northeast corner of the Forrest property was
sampled on February 21, 2001. The results demonstrate that all VOCs were below detection limits.
Inspections of the Forrest property conducted on January 28 and June 13-14, 2000, revealed storage
areas for agricultural chemicals and a pit for the disposal of residential waste.
The Phase II assessment scope of work included the drilling and sampling of:
twelve hollow -stem auger borings to delineate the Tank Farm Road pipeline release;
2) five exploratory hollow -stem auger borings along the property line shared with the former tank
farm;
3) one hollow -stem auger boring near the garbage pit located south of the farm house;
4)
five shallow hand-augerborings within and surroundingthe buildings used to store agricultural
chemicals; and
2Heminafter referred to as "Promega/ML."
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San Luis Obispo, Califomia March 20, 2001
5) three shallow soil samples from the cultivated fields.
In addition, the scope of work included the drilling, sampling and installation of one ground water
monitoring well (to supplement the tank farm ground water monitoring network).
The Phase II assessment scope of work:
1) delineated the extent of petroleum in soil at concentrations greater than 100 mg/kg associated
with the Tank Farm Road pipeline release; _
2) provided no evidence of impacts to the Forrest property resulting from petroleum released at
the adjacent tank farm. TPH was not detected in any of the soil samples retrieved from borings
drilled along the shared property line and no dissolved -phase constituents were detected in the
monitoring well;
3) revealed no evidence of shallow soil impacts related to petroleum releases caused by the 1926
fire; and
4) revealed no evidence of significant impacts resulting from the improper storage, handling,
and/or use of agricultural chemicals or other hazardous materials or wastes.
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arrest Property March 20.2001
i0 INTRODUCTION
his report presents the findings of the assessment performed at the Forrest property (APN 076-351-
?03) located on the north side of Tank Farm Road, immediately west of Unocal I s former tank farm
=n San Luis Obispo County, California. The objectives of the assessment were twofold:
E) to delineate the on -site extent of petroleum hydrocarbons associated with the Tank Farm Road
pipeline release; and
to determine whether current or previous land use at or adjacent to the subject property may
have resulted in the release of hazardous substances or petroleum to the environment.
t o address these objectives, the following scope of work was performed:
a Phase I assessment of the property in accordance with ASTM Standards (E1527-97) to
identify areas of potential concern related to historical site uses;
=) a Phase II assessment (i.e., soil sampling and analytical testing) of areas of potential concern,
including areas bordering the former tank farm and areas subject to surface releases resulting
from the 1926 fire; and
drilling, soil sampling and analytical testing to refine (to 100 mgft g) the delineation of
petroleum in soil associated with the Tank Farm Road pipeline release.
2.0 ENVIRONMENTAL SETTING
2.1 Site Location and Description
The subject site is a 20-acre agricultural property located on the north side of Tank Farm Road,
immediately west of Unocal's former tank farm (Figure 1). Meissner Lane and Tank Farm Road form
-ie parcel's northern and southern boundaries, respectively. Access to the site is via Meissner Lane.
Ta the west is another agricultural parcel that is currently under cultivation. Several structures occupy
rhe northwest comer of the site (Figure 2). These include a small house, an outhouse, a larger storage
shed and a smaller shed. With the exception of the small corner of the site occupied by structures, the
roperty is kept under nearly constant cultivation. A variety of crops are grown on the property
sncluding squash, garlic, corn, beans, peppers, and tomatoes.
inspections of the site conducted on January 28 and June 13-14, 2000, revealed pallets, boxes and other
packing materials stored in the larger shed. There were also several large bags of fertilizer stored in
the southeast corner of the shed. Adjacent to the shed on its north side is a small fenced area. On the
north side of the fenced area is the small shed which is used to store agricultural chemicals (pesticides
and herbicides). The door to the small shed is locked and has a poison warning stapled to it.
SL0006722 em"iro.,,
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Forrest Property Page 2
San Luis Obispo County, California - March 20, 2001
2.2 Geology and Hydrogeology
The subject site is situated in the San Luis Valley, a relatively level, narrow, -alluvium -filled basin in
the Coast Ranges Geomorphic Province. Numerous exploratory and water well borings drilled in the.
site vicinity indicate that this alluvium consists of approximately 160 feet of laterally discontinuous
interbeds of gravel, sand, silt and clay. The lithologic logs indicate that fine-grained lithologies, silt
and clay are predominate in the upper 100 feet, whereas coarse lithologies, sand and gravel are
predominate at depth. The alluvium rests unconformably upon bedrock of the Franciscan Formation.
The alluvium comprises the major ground water aquifer in the San Luis Obispo ground water basin.
In the site vicinity, ground water has been measured at depths ranging from 7 to more than 30 feet
below ground surface. Both long-term and seasonal fluctuations in ground water levels have been
recorded. Observations of rising water levels in exploratory borings suggest that the shallow ground
water is largely semi -confined with local confined and unconfined zones. The potentiometric surface
slopes to the southwest (mean flow direction=S65° W) with a gradient ranging from approximately
0.002 to 0.008 foot/foot. Recharge apparently occurs over the entire aquifer mainly through
precipitation events.
A ground water quality study of the San Luis Obispo Airport area (Cleath, 1986) concluded that
ground water quality in the airport area is poor and generally does not meet drinking water standards.
Total dissolved solids (TDS), nitrate, and chloride concentrations commonly exceed recommended
drinking water standards. Many of these water quality impacts (i.e., nitrate, chloride, TDS) are
attributed to the septic systems that serve the businesses and residences in the Airport Area.
3.0 HISTORICAL SITE CONDITIONS
The following site history has been compiled from a review of available historical information. The
earliest documentation available for the site is a historical topographic map dated 1895. This map
shows the property as undeveloped land. The earliest photographs of the site, Aston photos of
construction of the adjacent tank farm, dated August 1910, show several agricultural buildings
occupying the southern portion of the property. Based on review of historic aerial photographs and
maps, the Forrest property has been used for agricultural purposes since the late 19" century.
3.1 Historic Photographs
The following aerial photographs were reviewed to determine period site use(s): 1926, 1949, 1957,
1959,1965, 1972, 1989, and 1994. In addition, several c.1910 photographs from the Aston Collection
showing construction of the adjacent tank farm, also show portions of the subject property. Copies
of the 1926, 1949, 1959, 1965, 19727 1989, and 1994 aerial photographs are included in Appendix A.
,,T
SL0006723
SITE ASSESSMENT REPORT
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San Luis Obispo County, California _ _ March 20, 2001
1910 The focus of the Aston Collection photographs is construction of the tanks, reservoirs and
pipelines on the adjacent tank farm property. However, several ofthese photographs also show
portions of the Forrest property. These photographs reveal that several buildings occupied the
northwest comer of the property. The largest of these structures appears to be a bam
surrounded by several smaller sheds. The house that presently occupies the property was
present in 1910 (Aston Photo No. 77, dated August 10, 1910).
1926 On April 7, 1926, a lightening strike ignited two of the large oil reservoirs at the adjacent tank
farm. The fire eventually spread to most oil storage tanks resulting in a release of petroleum
that flowed over most of the tank farm, as well as portions of adjacent properties_ The May
1926 aerial photograph indicates that the southeast comer of the Forrest property may have
received some surface oil flow as a result of the fire. The photo also shows that the northwest
comer (2-3 acres) of the Forrest property was occupied by seven structures. The house, a small
building behind the house (likely an outhouse), a large barn and four smaller sheds (Figure 2).
The land surrounding the house appears to be planted with a small orchard with possibly some
row crops to the south. No other structures are visible on the property. Whether the remaining
17-18 acres were under cultivation or being used as pasture is unclear. If they were under
cultivation, it was as grain or animal feed, rather than row crops. Properties to the north, south
and west are agricultural. The former tank farm is to the east. Three 55,000-barrel above-
ground petroleum storage tanks are situated immediately east of the property line. Tank rings
(earthen berms constructed as secondary containment for above -ground storage tanks), but no
storage tanks, are evident on the property to the northeast.
1949 Between 1926 and 1949 few changes were made to the property. A small shed, currently used
to store pesticides/herbicides, was constructed between the house and the large barn (Figure 2).
The orchard and row crops surrounding the house were removed and the land was added to the
larger area of general cultivation. The four small sheds, situated east of the barn, were
reconfigured. Except for the few acres occupied by the house, barn, and sheds, the remainder
of the property was vacant and under cultivation. The site was surrounded by agricultural
properties on the north, west and south. The tank farm is located to the east. The tank berms
formerly observed on the property to the northeast have been removed.
1959 Few changes are evident on the 1959 aerial photograph. The structures visible on the 1959 air
photo appear unchanged from those noted on the 1949 photo. The irrigation well, located in
the northeast corner of the site (Figure 2), was added sometime between 1949 and 1959. The
remainder of the property was still vacant and appears under cultivation. Except for the tank
farm on the east, the surrounding properties were agricultural.
1965 Land -uses shown in the 1965 photograph do not differ significantly from the 1959 photograph. -
Except for the previously described structures in the northwest comer, the property was still
agricultural. The tank farm is situated to the east'and properties to the north, west and south
SL0006724 E 0 V I R 0 lq A E 11EUisI E
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were undeveloped agricultural. The southern -most of the three 55,000-barrel above -ground
petroleum storage tanks bordering the site on the east has been removed. The property cater -
comer to the southwest appears to have been developed as a concrete plant.
The 1972 photograph shows that the land uses do not differ significantly from the 1965 (and
earlier) photographs. Except for the tank farm, the site and surrounding properties were still
agricultural. The private residence, south of the tank farm and cater -corner (southeast) from
the subject property, was added between 1965 and 1972.
Although the resolution is poor, the 1989 photograph -shows that the subject property land -use
was still agricultural (row crops) and that the seven previously described structures still
occupied the northwest comer. The years from 1972 to 1989 marked a period of rapid develop
in the site vicinity. Industrial parks were constructed north and south of the subject property.
The tank farm still occupied the property to the east and the property to the west was still
agricultural.
1994 The 1994 photograph shows that the subjectproperty land -use has not changed. Between 1989
and 1994, all of the above -ground petroleum storage tanks at the adjacent tank farm were
removed. The site is now bordered on the north and south by industrial parks and on the west
by agricultural property. Some time between 1994 and 1997, the four small sheds situated east
of the barn, were removed.
3.2 Sanborn Fire Insurance Maps
A search for historical Sanborn Fire Insurance Maps was made through EDR-Sanborn Company..
According to EDR-Sanbom, Sanborn maps published for San Luis Obispo did not cover the site
vicinity.
3.3 United States Geological Survey Topographic Maps
Historical topographic maps published by the United States Geological Survey (USGS) for the San
Luis Obispo (7.5' and IT), Arroyo Grande (15') and Pismo Beach (7.5') areas were reviewed.
Topographic maps dated 1895, 1942, 1952, 1965, 1976, 1979, and 1994 were reviewed. Copies of
the topographic maps are included in Appendix A and a summary of the information is presented
below:
1895 The subject and surrounding properties are shown as undeveloped land. Although structures
are shown in the site vicinity, no structure is shown on the subject property. Neither the tank
farm, Tank Farm Road, nor Meissner Lane have been constructed.
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€st Property - Page 5
Luis Obispo County, California March 20 2001
I42 Although a small (agricultural or residential) structure is shown on the property to the west,
no_structure(s) are shown on the subject property. The subject property is depicted as
undeveloped. The tank farm is present to the east and Clark Field (Airport) is, shown cater
comer to the site on the northeast. Based on the aerial photographs and topographic maps,
Clark Field, occupied this property from some time after 1926 until some time prior to 1949.
52 The house is shown on the 1952 topographic map. The remainder of the property, as well as
surrounding properties on the north, south and west are undeveloped. Three above -ground
petroleum storage tanks are shown adjacent to the subject property on the east.
55 The 1965 topographic map shows two structures on the property, probably the house and barn.
The remainder of the property, as well as properties to the north, south and west are shown as
undeveloped.
76 The subject property is depicted as undeveloped with two small buildings near the northwest
corner. Two above -ground petroleum storage tanks are shown east of the property line.
Undeveloped properties exist to the north and west. Several commercial/industrial buildings
have been added on property to the south.
14 The 1994 topographic maps show three buildings on the property. Two are the house and the
bam,,but the nature of the third, which is located between and slightly east of the house and
bam, is unclear. The remainder of the property and the property to the west are undeveloped.
Commercial/industrial development has been added in the areas north and south of the
property. Two above -ground petroleum storage tanks are shown on the tank farm east of the
property line.
Chain -of -Title
hain-of-title search was not performed as part of the scope of work.
County Department of Planning and Building
County of San Luis Obispo Department of Planning and Building is the agency responsible for
ing building permits within the unincorporated areas of San Luis Obispo County. The agency's,
Frds date back to 1958. No building permits were on -file with the department for the subject
aerty.
San Luis Obispo Tank Farm
aced immediately east of the Forrest property is a portion of:Union Oil Company of California's
peal) San Luis Obispo tank farm. From 1910 until the early 1980s, the 325-acre tank farm was
TEN GLA_
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SanLuisObispo County Califomia March 20 2001
used principally for storing and distributing crude oil transported via pipeline from the San Joaquin
Valley. Storage facilities at the site included six large earthen reservoirs and 21 above -ground steel
storage tanks. In 1926, a lightening strike ignited a major fire at the tank farm destroying many of the
tanks and reservoirs and releasing millions of barrels of crude oil.Crude oil released as a result of the
1926 fire and in the course of site operations has impacted soil and ground water beneath several areas
of the site. Drilling and soil sampling performed on the tank farm, along the property line bordering
the Forrest property (Figure 2), have not identified petroleum impacts extending off the tank farm
property (England & Associates, April 1999).
There are 60 ground water monitoring wells on and surrounding the tank farm. None of the wells
monitoring the crude oil have ever exceeded the 1 ppm action level for petroleum hydrocarbons
promulgated by the Regional Water Quality Control Board - Central Coast Region (RWQCB) (Earth
Systems Pacific; 2000).
In addition to crude oil storage, regional pipeline operations were conducted out of several buildings
located on the northwest comer of the tank farm - adjacent to the Forrest property (Figure 2). These
buildings included offices, shops, and warehouses, as well as a crude oil pump station complete with
boilers and heat exchangers. The operations area also included other facilities including a small
petroleum testing lab and a fire school. Ground water beneath the former operations areas has also
been impacted by releases of fuel hydrocarbons associated with the former fire school (England Shahin
& Associates, 1992and 1994). Ground water sampling conducted on the tank farm and southeast
comer of the Forrest property in 1993 using a GeoProbe (England, Shahin & Associates, 1994)
indicated that elevated concentrations of purgeable (Cq C10) hydrocarbons and BTEX might extend
onto the southeast corner of the Forrest property. Ground water monitoring wells (MW-49 and
M W-50) installed on and south of the Forrest property (Figure 2) have not shown an off -site TPH- or
BTEX-impact to water quality.
The tank farm was serviced by a pipeline that runs parallel to and beneath Tank Farm Road, west of
the former tank farm (i.e., Tank Farm Road pipeline; Figure 2). The pipeline is actually a pipeline
system which has been renewed over the years. The original pipeline went in around 1910 with line
renewal projects in 1930 and 1952. The current pipeline consists of two 8-inch diameter steel pipes
which were installed around 1952, and removed from service in the mid- 1990s.
In April 1988, local landowners notified Unocal that crude oil contamination of soil and ground water
had been detected beneath their properties during real estate pre -purchase soils investigations (Pacific
Geosciences, Inc., 1988). Unocal subsequently retained Brown and Caldwell to initiate an
investigation to define the limits of the affected soil and ground water (1988 and 1989). Dames and
Moore (1990) and Earth Systems Consultants (1996a, 1996b, 1996c, and 1997) were later retained to
further delineate the impacts. These assessments resulted in the drilling of 122 exploratory borings,
the installation of 27 ground water monitoring wells,, and the delineation of a roughly linear zone of
hydrocarbon contamination approximately 200 feet wide by 2,000 feet long. Borings drilled on the
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March 20 2001
Forrest and adjacent properties have delineated the extent of petroleum in soil at concentrations greater
than N 1,000 mg/kg. Figure 2 shows the locations of borings drilled in the site vicinity.
England Geosystem conducted studies, including ground water pumping and computer modeling
which demonstrate that the oil and the individual hydrocarbon compounds which make up the oil are
not migrating from the impacted zone (England, Shahin & Associates, 1990a, 1990b, 1992a, and
1992b; England & Associates,1996). Most soil and ground water analyses have shown non -detectable
concentrations of the more toxic and mobile BTEX (benzene, toluene, ethylbenzene and xylenes)
components. Health risk assessments of exposure to petroleum -contaminated soil and groundwater
conducted in 1990 and updated in 1996 showed acceptable risk from leaving the crude oil in the
subsurface. More than a decade of quarterly ground water monitoring has shown that the dissolved
hydrocarbon plume is not expanding and has stabilized near the oily zone in the 60f years since the
leak occurred.
3.7 Environmental Records Review
3.7.1 County of San Luis Obispo Division of Environmental Health
The County of San Luis Obispo Division of Environmental Health (DEH) is the lead agency
responsible for enforcement of state and local hazardous materials and solid waste regulations in San
Luis Obispo County. The DEH has no records pertaining to hazardous materials and solid waste on
file for the Forrest property (265 Meissner Lane, APN 076-351-003).
Inspections conducted on January 28 and June 13-14, 2000, indicated that the property is served by
an on -site water well located in the northeast corner of the property (Figure 2). Presently the water
well is used for irrigation purposes. Historically, the well likely also provided water to the private
residence. The DEH is the lead agency responsible for enforcement of state and local regulations
regarding well construction, modification, and destruction. The files at DEH were searched for
information on the identified well. DEH records indicate two wells on the property: one near the
northeast comer and a second near the center of the south -half of the property. Other than the well
owner's name (William Forrest), the property street address, and assessor's parcel number, no
information (i.e., year drilled, permit number, well design, lithologic log, use, water quality, water
- level) for the wells was available from DEH. Subsequent visits to the site were unable to locate this
second well and it is presumed destroyed.
3.7.2 California Regional Water Quality Control Board -Central Coast Region
Database lists for sites under the purview of the Underground Storage Tank (UST) and Spills, Leaks,
Investigations and Cleanup (SLIC) programs of the California Regional Water Quality Control Board -
Central Coast Region (RWQCB) were reviewed. The subject property is not listed on either of these
databases (RWQCB, November 2000). The tank farm to the east is listed in the SLIC database four
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separate times: 1) tank farm, 2) Tank Farm Road pipeline, 3) a former UST, and 4) the BTEX plume
(see Section 3.6 for details).
3.7.3 Environmental Database Information
A search of federal and state environmental agency databases was performed by Environmental Data
Resources, Inc. (EDR). The EDR report is included as Appendix B. The databases were reviewed to
identify recognized environmental conditions associated with the site or surrounding sites within the
ASTM-prescribed search radii (ASTM E 1527-97). Thirty-seven federal and state databases were
queried as part of EDR's search. The results of the search are summarized in Table 1. Only those
databases that contained sites within the search radius (and those databases that should have contained
sites, but did not) are included in the table. For a complete list of the databases searched, refer to
Appendix B.
The tank farm did not show up in any of databases queried. Records reviewed at the RWQCB in San
Luis Obispo showed that portions of the tank farm and adjoining Tank Farm Road were included on
both the UST (or LUST) and CA SLIC databases. Other than the tank farm and its appurtenant
structures, the only other site listed in the databases that: 1) is close enough, and 2) handled a quantity
of hazardous substances sufficient to potentially impact the Forrest property, is Promega Biosciences,
Inc. (formerly JBL Scientific; hereinafter referred to as "Promega/JBL"). This site is located <1a-mile
north-northwest of the subject property (277 Granada Drive) and has experienced releases of
chlorinated solvents that have reportedly impacted water quality (Figure 2).
Files pertaining to the Promega/JBL property were reviewed at the offices of the RWQCB in San Luis
Obispo on February 22, 2001. This review revealed that the property has been occupied by a research,
development, and manufacturing facility for biochemical (blood and urine test kits) and pharmaceutical
products since its original development in 1987. A Phase I Environmental Assessment Report
indicated that the company uses hazardous chemicals in its production processes and produces
hazardous wastes (Earth Systems, 1994). Two soil and ground water investigations were conducted
on the property in 1996, resulting in the drilling and sampling of fourteen exploratory borings (Pacific
Engineering Associates, 1996a, 1996b). Concentrations of volatile organic compounds (VOCs),
notably toluene, xylenes, tetrachloroethene (PCE) and chloroform, were identified in soil and shallow
ground water. The central courtyard (approximate center of the property) was identified as the
suspected source of PCE and chloroform detected in the ground water.
Seven ground water monitoring wells were installed on the property in December 1996 (Pacific
Engineering Associates, 1997). These seven wells and two off -site wells, San Luis Sourdough well
(north of site) and Farm House well (south of site'), have been monitored on about a dozen occasions
3The Farm House well is located on the property immediately west of the Forrest property.
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SL0006730
SITE ASSESSMENT REPORT
Forrest Property
_San Luis Obispo CountyCalifornia Page 10
March 20 2001
between late 1996 and mid-20004. The results indicate that ground water occurs beneath the site at
depths ranging between 6 and 20 feet bgs. Ground water flow is toward the southwest at a gentle
gradient (0.007 Wit). Historically, chloroform and PCE have been detected in on -site water samples
at concentrations of up to 190 and 22 µg/L, respectively. More recent concentrations have been much
lower and on the July 19, 2000 monitoring date none of the VOCs were detected at concentrations
above generally accepted regulatory action levels (Pacific Engineering Associates, 2000). In general,
the impact to water quality is largely limited to the property. A risk assessment was performed for the
property by Mission Geoscience (February 24, 2000). The assessment indicated no significant
risk/hazard to human health and recommended risk -based closure and no further action with regard
to remediation of ground water. RWQCB correspondence daied October 2000 indicated that ifthe low
VOC concentrations detected in July 2000 are confirmed in future monitoring events, then they would
consider conditional closure.
Given the findings of the RWQCB file review and the cross -gradient location of the site relative to the
Forrest property, it is unlikely (but not impossible due to changes in flow direction created by irrigation
pumping) that contaminants released at Promega/JBL have impacted or will impact water quality at
the subject property. To evaluate the possibility of water quality impacts, the irrigation well on the
Forrest property, which adjoins the Promega/JBL property, was sampled and tested for the presence
of VOCs (EPA Method 8260). The sampling procedure is presented in Section 4.7 and the results are
presented in Section 7.5.
3.8 Phase I Assessment - Conclusions
The subject property was likely used for agricultural purposes since before the tuna of the 19`h century.
Some time between the late 1890s and 1910, a private residence and several agricultural buildings were
constructed near the northwest comer of the property. In 1910, Union Oil Company of California
constructed a large crude oil tank farm and pump station east of the property and pipelines along the
south border of the property. In 1926, a lightening -sparked fire at the tank farm resulted in a release
of petroleum that may have impacted the southeast comer of the Forrest property. In the late 1980s,
crude oil released from a pipeline underlying Tank Farm Road was discovered beneath several
properties bordering the road, including the Forrest property. In the early 1990s, subsurface
investigations of a BTEX occurrence in the offices area of the tank farm indicated that elevated
concentrations ofpurgeable (C; Crn) hydrocarbons and BTEX might extend onto the southeast corner
of the Forrest property. A search of federal and state environmental agency databases identified one
other site, Promega/JBL, with the potential to impact the subject property. The Promega/JBL facility
borders the Forrest property on the north and has experienced releases of chlorinated solvents that have
impacted water quality.
QThe most recent ground water monitoring report on file at the RWQCB was dated September 13. 2000 (Pacific
Engineering Associates, September_2000).
SITE ASSESSMENT REPORT
Forrest Property - - Page 11
San Luis Obispo County; California March 20 2001
Inspections of the Forrest property conducted on January 28 and June 13-14, 2000 revealed storage
areas for agricultural chemicals and a pit for the disposal of residential waste. Storage, handling,
and/or use of agricultural chemicals or other hazardous materials or wastes may have resulted in
unauthorized releases to the environment.
4.0 PHASE II ASSESSMENT
Given the findings of the Phase I Assessment, a Phase II scope of work was undertaken to achieve the
following:
1) Refine therm -property delineation of the Tank Farm Road pipeline petroleum release.
2) Install an additional ground water monitoring well (MW-56) near the southeast corner of the
property to determine whether ground water impacted by fuel hydrocarbons is migrating onto
the property.
3) Determine if petroleum released as a result of the 1926 fire impacted shallow soils on the
southeast corner of the subject site.
4) Evaluate the potential for impacts to the Forrest property from the adjacent former tank farm.
5) Determine whether site impacts have occurred as a result of storage, handling, and/or use of
agricultural chemicals or other hazardous materials or wastes.
4.1 Refine Delineation of Tank Farm Road Pipeline Release Plume
To more accurately define the extent of petroleum in soil associated with the Tank Farm Road pipeline
release, a series of delineation borings were drilled (Figure 3). To accomplish the delineation
efficiently, the following phased approach was used:
an initial boring (B#-A) was drilled at a location approximately 100 feet north of Tank Farm
Road;
if the initial boring was "clean" ("clean" refers to soil samples which revealed no discernable
evidence of petroleum [i.e., residual oil, stained soil, and/or petroleum odor]), a second boring
(B#-B) was drilled 40 to 50 feet closer to Tank Farm Road;
if the initial boring was "dirty" (i.e., soil samples display evidence of petroleum), a second
boring (B#-B) was drilled 40 to 50 feet further from Tank Farm Road.
SL0006732 Fnsr,;n:,a? en cu;EEe t:_
SITE ASSESSMENT REPORT
12
7:1-is process (moving incrementally toward or away from the zone of oil in soil) was repeated at each
`the six (13-1 through B-6) delineation boring locations until a "dirty" and a "clean" boring were
~thieved.
=J A Drilling and Sampling Protocols
:e borings were drilled with a truck -mounted, hollow -stem auger drill rig to depths of 30 feet.
elatively undisturbed soil samples were collected from the borings at 5-foot depth intervals,
'ginning at a depth of 5 feet, using a nominal 2-inch diameter, California -modified split spoon
zampler lined with stainless steel sample sleeves. The recovered sleeves were sealed with Teflon
=-testing, plastic caps, and Parafilm. The samples were labeled with sample point identification and
-ate and time of collection andstoredon ice until delivered to ZymaX Envirotechnology, a state-
ae,h hied environmental testing laboratory, for analysis. Representative portions of the soil cores were
-,aced in resealable plastic bags and field screened for volatile organics using a photoionization
_erector (PID). The borings were logged by a Certified Engineering Geologist and backfilled with
::�ntonite grout.
-fter each sampling event, the sampler was washed in a detergent solution, rinsed in tap water, and
:nenrinsed in distilled water. These methods are meant to decontaminate the sampler to prevent cross-
aontamination between sampling events. The auger flights and bits were also decontaminated by
_ressure washing with steam between each boring.
4.2 Assessment of Surface Impacts from the 1926 Fire
Shallow soil samples were collected from delineation borings 13-5A, 13-513, 13-6A, and monitoring well
NIW-56 to determine if petroleum released as a result of the 1926 fire impacted shallow soils on the
southeast corner of the subject site (Figure 3). Prior to hollow -stem auger drilling, these four borings
were hand augered to a depth of 5 feet. The hand augering method allowed detailed examination of
:he soil in the upper 5 feet of the site. Separate boring logs were prepared for the hand augered borings
and are included in Appendix C. Soil samples were collected from the borings at depths of 1 and 5
feet below ground surface (samples would have been collected from additional depths had evidence
of petroleum been observed). Recovered soil samples were handled in accordance with the methods
described in Section 4.1.1.
Investigation of Perimeter Bordering Former Tank Farm
To evaluate the potential for impacts to the Forrest property from the adjacent former tank farm, five
borings (B-7 through 13-11) were drilled along the shared property boundary. The boring locations are
depicted on Figure 3.
E N G L A:I`,TD
Cr nnn4�11 eniviaor�a�eralN� �ru�iraeegirec
SITE ASSESSMENT REPORT
Forrest Property Page 13
San Luis Obispo County, California March 20, 2001
The borings were drilled with a truck -mounted, hollow -stem auger drill rig to depths of 30 feet.
Relatively undisturbed soil samples were collected at 5-foot depth intervals from the borings,
beginning at a depth of 5 feet, using the procedures previously described. The borings were logged
by a Certified Engineering Geologist.
4.4 Other Areas of Concern
Historical records indicate that the Forrest property has been used for agricultural purposes (farming
and ranching) since before the turn of the 19' century. Inspection of the property revealed storage
areas for agricultural chemicals and a pit for the disposal of residential waste. To screen the site for
elevated concentrations of agricultural chemicals and unauthorized dumping in the garbage pit, the
following sampling and testing program was conducted:
collection and testing of three representative surficial soil samples from the agricultural fields
(S-1 through S-3);
collection ofshallow soil samples from five hand auger borings located within and surrounding
the sheds storing agricultural chemicals (SB-1 through SB-5); and
drilling an angled hollow -stem auger boring to obtain soil samples from beneath the garbage
pit (B-12).
The areas of interest and the shallow soil sampling points are depicted on Figure 3. At each shallow
soil sample collection point (S-1 through S-3), samples representative of the upper six inches of soil
were collected using a clean garden trowel and packed into 8-ounce glass jars provided by the
analytical laboratory. Within and surrounding the sheds storing agricultural chemicals, soil samples
were collected at depths of 0.5 feet and 2.5 feet from each of the five sample collection points. The
samples were collected by advancing the boring to the desired depth with the hand auger and manually
driving a soil sampling device containing a single 2-inch diameter by 6-inch long stainless steel sample
tube into the undisturbed soil.
A hollow -stem auger boring was drilled to a depth of 30 feet at an angle of 15 degrees from vertical
and oriented so as to explore beneath the garbage pit. Relatively undisturbed soil samples were
collected at 5-foot depth intervals beginning at a depth of 5 feet, using the sampling and handling
procedures previously discussed.
4.5 Additional Monitoring Well
GeoProbe ground water sampling conducted as a part of the BTEX ground water investigation
(England & Associates, 1994) suggested that low levels of fuel hydrocarbons in ground water might
extend beyond the tank farm property boundary near Tank Farm Road. Groundwater Technology, Inc.
(GTI,1995) installed two additional ground water monitoring wells in this area, MW-49 and M W-50,
but these wells effectively bracketed (north and 'south) the area where fuel hydrocarbons were
;1 , r
SL0006734 I; VIR0NIII LN*Ai ee,G VEERING
SITE ASSESSMENT REPORT
Forrest Property
Page 14
suspected of migrating beyond the property lines. To determine whether ground water impacted by
fuel hydrocarbons is migrating beyond the property lines, an additional monitoring well (MW-56) was
installed half way between wells MW-49 and MW-50 (Figure 3).
Ground water monitoring well MW-56 was drilled with a truck -mounted, hollow -stem auger drill rig
to a depth of 40 feet. Ground water was encountered at approximately 7 feet below ground surface.
During drilling, soil samples were collected at 5-foot depth intervals and the well was completed with
4-inch diameter well screen and casing. The upper 5 feet of casing is blank and the lower 35 feet is
slotted (0.02-inch). The annulus surrounding the slotted section was backfilled with No. 3 Monterey
sand. The filter pack was extended I to 2 feet above the top of the screen and the sanitary seal was
installed. The sanitary seal consists of hydrated bentonite chips. The casing is protected with a
locking; steel, above -ground well monument.
The soil samples were handled and the sampling and drilling equipment decontaminated in accordance
with the procedures described previously. The monitoring well was pre -developed at the time of
installation (June 21, 2000) using a combination of surging and bailing. On June 23, 2000 the well
was developed by purging five casing volumes (110 gallons) of water using a submersible pump.
Physical parameter measurements and observations made during development are presented on the
Monitoring Well Development Form in Appendix D. The monitoring well was purged of four casing
volumes (92 gallons) for sampling on July 21, 2000. Purging was performed using a pre -cleaned
electric pump and dedicated sampling hose. Field measurements of pH, electrical conductivity,
temperature, and turbidity were obtained during purging and are presented in Appendix D. The well
was sampled using a disposable polyethylene bailer and string. Each sample was placed in the
appropriate containers provided by the analytical laboratory. The sample containers were labeled and
placed on ice pending delivery to the analytical laboratory.
4.6 Survey
The elevation and horizontal location of each boring, wellhead, and shallow soil sample collection
point was surveyed on June 15, 2000 by Engineering Development Associates, Inc. (EDA). a
California -licensed surveyor. Wellhead casing elevations were surveyed to within t0.02 ft. The
surveyor's report is included in Appendix E.
4.7 Irrigation Well
The irrigation well located in the northeast corner of the Forrest property was sampled on February= I _
2001, to determine whether releases of chlorinated VOCs on the adjacent Promega/JBL propart%- a7 e
impacted water quality. The sampling was performed after several days of rain and the pump was no,
operating at the time of sampling. The well head does not have an access or sample port, so sam '.^_
was performed by starting the pump, letting it rugfor a minute or two, and collecting the saml ee ;
cr nnniz7ze e,`,
SITE ASSESSMENT REPORT
Forrest Property Page 15 i
San Luis Obispo County, Californiaarch 20. 2001
ia l
i
the end of the discharge pipe. Three 40 milliliter VOAs were collected from the well, labeled, and
placed on ice pending delivery to the analytical laboratory.
5.0 TESTING PROGRAM
Soil samples recovered from the borings (B-I through B-12) and the ground water sample from
MW-56 were analyzed for Total Petroleum Hydrocarbons (TPH) quantified in the nC, to nCjo carbon
range and benzene, toluene, ethyl benzene and total xylenes (BTEX) using U.S. EPA Test Method
8260, and TPH quantified in the nCto to nCZs and nC,s to nC40carbon ranges using U.S. EPA Test
Method 8270. Select soil samples were tested for the 17 California Assessment Manual (17 CAM)
metals (U.S. EPA Test Methods 6010/7000) and volatile organic compounds (VOCs). The ground
water sample from the irrigation well was tested for VOCs.
Soil samples recovered from the agricultural fields and from within and surrounding the storage sheds
were tested for the 17 CAM metals (U.S. EPA Test Methods 6010/7000), pesticides and herbicides
(U.S. EPA Test Methods 8080/8150), and semi -volatile organic compounds (SVOCs) (U-S. EPA Test
Method 8270).
The chemical analyses of soil and ground water samples collected during the site assessment were
performed by ZymaX Envirotechnology, Inc., a Califomia-certified environmental testing laboratory.
All analyses were performed using USEPA, State of California, or other approved methods.
Analyte Test Protocol. .
TPH (C,,-C,, and C35 C,, carbon ranges) U.S. EPA Test Method 3270.
Polynuclear Aromatic Hydrocarbons (PAHs) U.S. EPA Test Method 8270
Benzene, Toluene, Ethyl benzene, Total Xylenes (BTEX) U.S. EPA Test Method 9260
TPH (C; C,,) and Volatile Organic Compounds (VOCs) U.S. EPA Test Method 8260
17 California Assessment Manual (17 CAM) Metals U.S. EPA Test Methods 601n-000
Semi -Volatile Organic Compounds (sVOCs) U.S. EPA Test Method S:'l
Pesticides/Herbicides U.S. EPA Test Methods 3051 8: e
6.0 FINDINGS OF FIELD INVESTIGATION
Soils encountered during drilling consisted of clay, sandy clay, and clayey sand. The upp - _A - feet
of the soil profile is dusky gray clay with fine- to coarse -grained sand. In most borings- a 0 =oot
thick layer of sand was encountered at approximately 8 feet below grade. Ground water was _ ;erally
encountered at a depth of 6 to 9 feet below grade. The boring logs are provided in Appenz:x C.
e - JD
SL0006736
SITE ASSESSMENT REPORT
Forrest Property .
San Luis Obispo County, March 6
March Page 1
Organic vapor analyzer (OVA) readings recorded on the boring logs (Appendix C) show an absence
of VOCs as demonstrated by readings of zero or generally less than 10 parts per million (ppm).
7.0 RESULTS OF LABORATORY ANALYSES
The chemical data collected during this assessment are summarized in Tables 2 through 7 and the
analytical laboratory reports are provided in Appendix F. A discussion of the results for the various
categories of compounds is presented below:
Petroleum Hydrocarbons _
None of the samples tested for BTEX showed any detectable concentrations (Table 2).
None of the soil samples collected from borings (13-7 through 13-11) drilled along the eastern
Property line (i.e., the property line shared with the former tank farm) and beneath the shallow
garbage pit (near the farm house) contained TPH above detection limits (Table 2).
The highest TPH concentration (12,310 mg/kg) was detected in a soil sample collected from
a depth of 15 feet below ground surface (bgs) in boring 13 4C, drilled near Tank Farm Road.
Most of the petroleum compounds comprising the TPH consist of longer chain (i.e., higher
molecular weight) hydrocarbons (CIO to C4.).
None of the soil samples collected to a depth of40 feet in boring MW-56 contained detectable
concentrations of TPH or BTEX.
The analytical data obtained from this assessment and previous investigations allows
delineation of the Tank Farm Road petroleum occurrence to the desired accuracy. The lateral
extent of TPH in soil at concentrations greater than 100 mg/kg is shown in Figure 2.
Cross -sections A -A', B-B', and C-C', Figures 4 through 6, depict the vertical extent of the
Tank Farm Road petroleum occurrence along the south edge of the Forrest property. These
figures show that TPH-impacted soil begins at a depth of about 5 feet bgs and extends to a
depth of approximately 20 feet.
Metals
Six soil samples from the borings (5 to 10 feet bgs) and eight shallow soil samples (0.5-feet
bgs) collected from the fields and from the area surrounding the storage sheds were tested for
the 17 CAM metals.
E 1'v! (13 L AAI_ N D
/
SITE ASSESSMENT REPORT
Forrest Property Page 17
San Luis Obispo County, .California March 20, 2001
• Of the 17 CAM metals, five (antimony, beryllium, selenium, silver, and thallium) were not
detected in any of the samples (Table 3 [borings] and Table 5 [shallow soil samples]).
The detected concentrations of all other metals were within the background range for
California soils (Bradford et a1.,1996). Although they were within the expected range, several
metals concentrations were slightly elevated in the shallow soil samples (Table 5), relative to
the deeper (Table3) soil samples. Notable among these slightly elevated concentrations are
the lead results. Lead concentrations in shallow soils are frequently elevated as a result of
atmospheric lead deposition resulting from the historic use of automotive fuels containing
organolead compounds.
• Chromiumandnickel concentrations reflect the geochemistry of the Franciscan Formation
(local bedrock), which is the source of the soil.
7.3 Volatile Organic Compounds
• Two samples (B-12-10 and B-12-25) collected from the angle boring drilled beneath the
shallow garbage pit were tested for VOCs. As shown in Table 4, neither of the samples
contained detectable concentrations of volatile compounds.
7.4 Chlorinated Herbicides, Pesticides and Semi -Volatile Organic Compounds
• Shallow soil samples SB-1 through SB-5, collected from the vicinity of the agricultural
chemical and general storage sheds, and samples S-1 through S-3, collected from the cultivated
fields, were analyzed for chlorinated herbicides, pesticides, and semi -volatile organic
compounds (SVOCs). The results are summarized in Tables 6 and 7, and discussed below.
• None ofthe soil samples contained chlorinated herbicide concentrations above detection levels
(Table 6).
• As shown in Table 7, all of the SVOC concentrations were below detection limits.
Of the 20 pesticides assessed, six (chlordane, 4,4'-DDD, 4,4'-DDE, 4,4'-DDT, endrin, and
endrin aldehyde) were detected in some of the samples.
• The concentrations and spatial distribution of detected concentrations are indicative of
agricultural origin and use.
• Overall, the analytical data indicate that concentrations of the chlorinated pesticides are very-
low. For comparison purposes, EPA Region IX Preliminary Remediation Goals (PRGs) for '
residential and industrial sites are included in Table 7 for the compounds for which they are
A,
SL0006738
SITE ASSESSMENT REPORT
Forrest Property Page 18 _
San Luis Obispo County, Cal ifomia March 20, 2001 G
r
n
available. PRGs are estimated contaminant concentrations in soil that are protective of human g
health over a lifetime of potential exposure. As shown in Table 7, detected concentrations of
chlorinated pesticides are significantly less than the most conservative residential PRGs.
7.5 Ground Water Quality r
Well MW-56 was sampled on July 21, 2000 and tested for TPH in the C4 to C40 carbon ranges and
BTEX. The results, provided in Appendix F, demonstrate that TPH and BTEX were below their
corresponding detection limits.
The irrigation well was sampled on February 21, 2001 and tested for VOCs by EPA Method 8260.
The results, provided in Appendix F, demonstrate that all VOCs were below detection limits.
7.6 Phase II Conclusions
Previous studies have established that the southern boundary of the Forrest property was impacted by
petroleum released from pipelines underlying Tank Farm Road. This assessment delineated the extent
of petroleum in soil at concentrations greater than 100 mg/kg associated with that release.
This assessment also provided no evidence of impacts to the Forrest property resulting from petroleum
released at the adjacent tank farm. TPH was not detected in any of the soil samples retrieved from
borings drilled along the shared property line and no dissolved -phase constituents were detected in the
monitoring well
Historic aerial photographs dating to the time of the tank farm fire showed that the southeast comer
of the property may have been impacted by the released petroleum. Detailed logs of hand auger
borings drilled in this area of the site and analytical testing of shallow soil samples revealed no
evidence of shallow soil impacts.
Shallow soil samples collected from the cultivated fields, area surrounding the storage sheds, and
beneath the garbage pit revealed no evidence of significant impacts resulting from the improper
storage, handling, and/or use of agricultural chemicals or other hazardous materials or wastes.
If you have any questions regarding the information contained herein, please do not hesitate to contact'
the undersigned at 949-453-8085.
Respectfully submitted, d
Michael A. Rendina, C.E.G. 1426, C.HG. 292
Project Manager
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