|
_ I
<br /> -�IL> u L
<br /> CLEARWATER
<br /> . G R O U P, I N C
<br /> Environmental Services
<br /> GROUNDWATER MONITORING REPORT
<br /> FOURTH QUARTER 1998
<br /> Barnes Trucking Facility
<br /> 1817 South Fresno Avenue,
<br /> Stockton, California
<br /> December 21,1998
<br /> BACKGROUND
<br /> The Barnes Trucking facility is on the southwest corner of the intersection of Charter Way (State
<br /> Highway 4) and South Fresno Avenue (Figure 1) The property is located approximately 15 miles south of
<br /> the Port of Stockton Turning Basin and 0 9 mile east of the San Joaquin River (Figure 2) Currently, the site
<br /> is used as a truck dispatch center and parking area There are no fuel dispensing facilities operating at the
<br /> site
<br /> In letters dated September 18, 1992 and April 30, 1996, the San Joaquin County Public Health Services,
<br /> Environmental Health Division (EHD) indicated that additional investigation of tlus site was required
<br /> because petroleum hydrocarbons were detected in soil samples collected from an underground storage tank
<br /> (UST) excavation According to an April 30, 1996 EHD letter,two USTs were removed from the site on June
<br /> 15, 1992 Both USTs were 10,000-gallon capacity tanks that had been used to store fuel Four soil samples
<br /> were collected from the bottom of the excavation at a depth of approximately 16 feet below ground surface
<br /> (bgs) Soil samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg) as diesel fuel
<br /> (TPHd), as kerosene (TPHk), and as oil (TPHo) Samples were also analyzed for benzene, toluene,
<br /> ethylbenzene, and. xylenes (BTEX) The highest concentrations of TPHg, TPHd, and BTEX were detected at
<br /> 5,700 milligrams per kilogram (mg/kg) TPHg, 50 ing/kg TPHd, and 48 mg/kg benzene TPHk, and TPHo
<br /> were not detected in any of the four samples
<br /> On September 25, 1997, Clearwater Group, Inc (Clearwater) supervised the drilling of six soil borings to
<br /> depths of from 32 to 38 feet bgs Three of the bonngs were converted to groundwater monitoring wells(MW-
<br /> 1, MW-2,MW-3) Soli samples collected from four of the six borings contained detectable concentrations of
<br /> petroleum hydrocarbons The highest concentrations of TPHg (570 mg/kg) and benzene (4 0 mg/kg) were
<br /> detected in the sample from SB-2 at a depth of 25 feet bgs Groundwater samples collected September 29,
<br /> 1997 from all three monitoring wells contained detectable concentrations of dissolved petroleum
<br /> hydrocarbons The highest concentrations of TPHg at 32,000 micrograms per liter(gg/L)and benzene (2,200
<br /> gg/L)were detected in the sample from monitoring well MW-1 Low concentrations of TPHd were detected
<br /> in soil samples from SB-5 (11 mg/kg) and SB-6 (2 mg/kg), and in the groundwater sample from MW-1 (300
<br /> gg/L),however subsequent groundwater sample results have been non-detect for all three wells, and with
<br /> approval from the EHD, analysis for TPHd has been discontinued
<br /> After review of the Subsurface Investigation Report, dated November 20, 1997, the EHD requested
<br /> monitoring wells be installed to better define the areal extent of soil and groundwater contamination
<br /> After discussion with Lori Duncan of the EHD, Clearwater submitted the Workplan for Site Investigation
<br /> (Workplan), dated November 18, 1998 An addendum to the Workplan, dated December 10, 1998 was
<br /> submitted in response to EHD comments The Workplan and addendum was approved by the EHD on
<br /> December 15,1998
<br /> 520 Third Street,Swte 104 + Oakland,California 94607 • Telephone 510-893-5160 • Fax 510-893-5947
<br />
|