ARCHIVED REPORTS_XR0011509 - Laserfiche WebLink

Home Browse Search

V/1-1-117 Lone Palm Suite B vModesto California 95351 www atc-enviro com 209 579 2221 r Fax 209 579 2225 A S S O C 1 A T E 5 I N C October 16, 2001 54 62577 0001 ENARON" l_1 ALTH PERNII /SERVICES Ms Lori Duncan San Joaquin County Public Health Services Environmental Health Division 304 E Weber Street, Third Floor Stockton, California 95202 Subject Monitoring Report Second Quarter 2001, Diesel Performance, 2804 East Fremont Street, Stockton, California Dear Ms Duncan This report presents the results of quarterly groundwater monitoring and sampling performed in June 2001 by ATC Associates Inc at the site located at 2804 East Fremont Street, Stockton, California (Figure 1) Sampling was performed to monitor the concentrations of petroleum hydrocarbons in groundwater at the site Monitoring was performed to determine the . groundwater flow direction and the hydraulic gradient in the uppermost aquifer BACKGROUND In February 1987, SEMCO removed and disposed of one 3,000-gallon unleaded gasoline underground storage tank (UST), associated piping, and fuel dispenser from the location shown on Figure 2 A soil sample collected at 13 feet below ground surface (bgs) contained elevated concentrations of petroleum hydrocarbon contaminants The excavation was subsequently backfilled and resurfaced On July 23, 1997, an ATC geologist supervised the advancement of five soil borings ranging in depth from 6 to 46 feet bgs The soil borings were advanced using a truck mounted Geoprobe® narrow diameter rig employing direct push technology Soil samples were submitted for analysis and contained detectable concentrations of petroleum hydrocarbons Site activities were summarized in ATC's Summary Report for Subsurface Investigation, dated October 20, 1997 On September 25, 1998, ATC personnel supervised the advancement of soil boring MW1 at the site to a depth of approximately 65 feet bgs to evaluate groundwater for the presence of - petroleum hydrocarbons - The soil boring was completed as a groundwater monitoring well and --- -- on September 28, 1998 the well was developed and sampled Analytical data indicated that soil and groundwater samples contained detectable concentrations of petroleum hydrocarbons Field activities and analytical results were detailed in ATC's Summary Report of Additional Subsurface Investigation, dated January 8, 1999 w lwordpro%2577WR-2001 doe 1