|
r
<br />Chevron Products Company 2
<br />Former Chevron Station #9-5775, 01 West Kettleman Lane Lodi Cali fomia QcLober 9 2000
<br />subsurface facilities have been removed from the site. Locations of previously existing
<br />facilities are shown on Figure 2. The site is currently being developed as a Prime Shine
<br />Express car wash and auto lubricant center.
<br />Previous Investigations
<br />The five former USTs, hydraulic hoists, dispenser islands, and associated product
<br />piping were removed on August 24, 1998, by Musco Excavators (Gettler-Ryan, Soil
<br />Sampling During Underground Storage Tank and Piping Removal, dated November 10,
<br />1998). Soil samples were collected by Gettler-Ryan (G -R) beneath the USTs and
<br />product piping (Figure 2). Very low to nondetectable concentrations of petroleum
<br />hydrocarbons were reported in soil samples collected below the waste oil USTs, product
<br />lines, hydraulic hoist, and five of the six samples from the gasoline UST pit.
<br />Concentrations of total petroleum hydrocarbons as gasoline (TPHg), benzene, toluene,
<br />and methyl tertiary butyl ether (MtBE) were reported as 14,000 mg/kg, 84 mg/kg, 1,500
<br />mg/kg and 56 mg/kg, respectively, in the sample collected from 14-1/2 feet below
<br />ground surface (bgs) below the eastern end of the middle gasoline UST. The area
<br />beneath the eastern end of the middle gasoline UST was excavated from 14-1/2 to 16
<br />feet bgs, and a second soil sample was collected. Concentrations of TPHg, toluene, and
<br />MtBE were reported as 880, 52, and 11 mg/kg, respectively; benzene was reported as
<br />not detected in this sample.
<br />On August 31, 1998, the area beneath the eastern end of the middle gasoline UST was
<br />over -excavated from 16 to 22-1/2 feet bgs. Soil samples collected from the base and the
<br />eastern wail of the excavation were reported to contain concentrations of TPHg,
<br />benzene, and MtBE at 2,300 mg/kg, 4.1 mg/kg, and 330 mg/kg, respectively.
<br />Between January 25 and January 27, 1999, five soil borings were drilled by V&W at the
<br />subject site, with four of the borings completed as monitoring wells (G -R, Monitoring
<br />Well Installation Report, dated June 2, 1999). The four monitoring wells (MW -1
<br />through MW -4) were completed to 65 feet bgs. Soil samples collected by G -R from the
<br />borings had reported concentrations of TPHg, benzene, MtBE, and ethyl tertiary butyl
<br />ether (ETBE) up to 1,200 mg/kg, 0.81 mg/kg, 78 mg/kg, and 1.3 mg/kg, respectively.
<br />Groundwater samples collected from the monitoring wells had reported concentrations
<br />of TPHg, benzene, MtBE, ETBE, and tertiary amyl methyl ether (TAME) ranging up to
<br />11,000 ug/l, 6,800 ug/l, 62,000 ug/l, 2,400 ug/l, and 780 ug/l, respectively.
<br />In October of 1999, G -R continuously monitored the groundwater elevations at the site
<br />over a three-day period (G -R, Offsite Source Survey, dated November 2, 1999). The
<br />results of the study indicated that groundwater elevations fluctuate in daily cycles
<br />corresponding to the operation of nearby City of Lodi Municipal Well #12, located
<br />approximately 350 feet southwest of the site.
<br />0
<br />077.41991.04319-5775 WP 100900.doc
<br />
|