Laserfiche WebLink
�j <br /> GeoStrategies <br /> October 27, 1997 <br /> Mr. Ed Ralston <br /> Tosco Marketing Company <br /> Environmental Compliance Department <br /> 2000 Crow Canyon Place, Suite 400 <br /> San Ramon, California 94583 <br /> Subject: Third Quarter 1997 VES Report, Unocal Station No. 6981, 4707 Pacific <br /> Avenue, Stockton, California. <br /> Mr Ralston <br /> This report summarizes the sampling and operational data for the vapor extraction system <br /> (VES) at the subject site from July through September, 1997 Location of the subject site <br /> is shown on Figure 1 The current station configuration is shown on Figure 2 <br /> Third Quarter 1997 Activities <br /> f <br /> Field activities conducted at the subject site during the third quarter 1997 are discussed <br /> below GeoStrategies (GSI) Field Methods and Procedures are attached <br /> Influent and effluent vapor stream samples were collected by GSI on July 31, August 28, <br /> and September 28, 1997 The samples were analyzed for TPHg and BTEX at Sequoia <br /> Analytical in Redwood City, California (FLAP #1210). Copies of the laboratory reports <br /> and chain-of-custody documents are attached <br /> Between June 24 and September 28, 1997, the VES operated approximately 636 hours <br /> (26 5 days), or approximately 28% of the time. The VES continue&to have pr9blems <br /> flaming out Soil vapor was extracted from,w6l,ls..�VW-2, VW-4, and VW-5 during the <br /> third quarter 1997, as field monitoring indicated these wells had the highest hydrocarbon <br /> concentrations During the third quarter 1997, the VES extracted and treated <br /> approximately 339 pounds of TPI-Ig and 1 pound of benzene VES analytical data for the <br /> quarter are summarized in Table 1, and operational data are summarized in Table 2 <br /> i <br /> 785520-3 <br /> 3164 Gold Camp Drive, Suite 240 . Rancho Cordova, CA 95670 • (916) 631-1314 Fax (916) 631-1317 <br />