Laserfiche WebLink
t'r n 1117 Lone Palm Avenue, Suite B <br /> V /f Modesto, CA 95351 <br /> http://www.atcassociates.com <br /> RTC209.579.2221 <br /> Fax 209.579.2225 <br /> A a s o c 1 A T E s I N C . <br /> April 20, 2005 <br /> 54.26823.0001 <br /> NAY 0 <br /> Ms. Lori Duncan E pER0r"ENr HEALT}q <br /> San Joaquin County EFMCE <br /> Environmental Health Department <br /> 304 E. Weber Street, Third Floor <br /> Stockton, California 95202 <br /> Subject: Fourth Quarter 2004, Combined Groundwater Monitoring and Remediation <br /> Systems Operations and Monitoring Report, Jamar Service Station, 4075 East <br /> Main Street, Stockton, California <br /> Dear Ms. Duncan: <br /> This report presents the results of quarterly groundwater monitoring and sampling performed on <br /> December 13, 2004 at the Jamar property located at 4075 East Main Street, Stockton, California <br /> (Figure 1). It also reports the operations and monitoring (O&M) of the remediation system <br /> performed during the Fourth Quarter 2004 by ATC Associates Inc. (ATC). <br /> Quarterly groundwater monitoring and sampling was performed to monitor the distribution of <br /> petroleum hydrocarbons in groundwater and to evaluate the groundwater flow direction and <br /> hydraulic gradient in the impacted aquifers. O&M of the remediation system was performed to <br /> evaluate the effectiveness of the ozone air sparge system at remediating petroleum impacted soil <br /> and groundwater. <br /> 1.0 SITE HISTORY <br /> In 1995, one 500-gallon waste oil underground storage tank (UST) and one 500-gallon kerosene <br /> UST were removed from the site. <br /> In December 1998, two 6,000-gallon and one I0,000-gallon gasoline USTs were removed from <br /> the site. Soil samples were collected from the tank pit and analyzed for petroleum hydrocarbons. <br /> Lab analyses indicated the samples collected from the tank pit contained detectable <br /> concentrations of petroleum hydrocarbon constituents. The excavation was subsequently <br /> =.backfilled and a 20,000-gallon UST was installed. <br /> In September 1999, John P. Cummings & Associates (JPCA) advanced MW I, MW2, and MW3 <br /> to depths ranging from approximately 74 to 78 feet below ground surface (bgs). The borings <br /> l were completed as groundwater monitoring wells. <br /> E�f <br /> ENVIRONMENTAL, GEOTECHNICAL AND MATERIALS PROFESSIONALS <br />