ARCHIVED REPORTS XR0010263 - Laserfiche WebLink

Home Browse Search

Former Discovery Chevrolet <r='' December 7, 1994 Bays (Figure 2). Currently, the site is occupied by Tracy Chevrolet. No USTs are in place at the current operation. PREVIOUS WORK Based on information supplied by Ms. Nokes, we understand that the three USTs were removed in April, 1993. Four soil samples were collected from the base of the gasoline UST excavation at depths of approximately 9 to 10 feet below ground surface (bgs), one soil sample was collected from beneath the product dispenser at approximately 5.5 feet bgs, and one soil sample was collected from the base of the waste oil UST excavation at approximately 7.5 feet bgs. Groundwater was not encountered during UST removal. Information supplied by.. SJCEHD indicate that the product piping that ran from the gasoline USTs to the dispenser, located inside the Service Bays, was left in place beneath the concrete apron outside the shop building. Petroleum hydrocarbons were detected in all soil samples collected during the UST removal. Soil samples collected from the gasoline UST excavation contained Total Petroleum hydrocarbons as gasoline (TPHg) in concentrations ranging from 920 to 4,400 part per million (ppm). Benzene was detected in all these-samples at concentration ranging from 5.9 to 39 ppm. Total lead was detected in two soil samples at concentrations of 19 and 4.0 ppm. TPHg was detected in the soil sample collected beneath the product dispenser at a concentration of 21 ppm. Benzene was detected in this sample at a concentration of 0.88 ppm. TPHg, Total Petroleum Hydrocarbons as Diesel (TPHd), and benzene were detected in the soil sample from the waste oil excavation at concentrations of 31 , .270 and 0.18 ppm, respectively. Lead and chromium were detected in these samples at concentrations 7.8 and 9.2 ppm, which are below the total threshold limit concentrations (TTLC) used for classification of hazardous waste of soil but above their respective soluble threshold limit concentrations (STLC) of 5.0 ppm. Laboratory results from the UST removal are presented on Table 1 . PRESENT FIELD ACTIVITIES i Field work was performed in accordance with the GSI Site Safety Plan #6146.701 dated August 5, 1994. Underground Service Alert (USA) was notified prior to beginning drilling activities. The drilling was performed under a SJCEHD drilling permit. All field work was performed as described in the August 12, 1994 Work Plan and as describe in the GSI and G-R field procedures presented in Attachment A. 1 Report No.8146701.1 2 GeoStrategies Inc. i