Laserfiche WebLink
A � <br /> 1./ <br /> GeoStrateg ies <br /> • <br /> February 7, 1997 <br /> Mr. Adadu Yemane <br /> 76 Products Company <br /> P O Box 5155 <br /> San Ramon, California 94583 <br /> Subject: Fourth Quarter 1996 VES Report, Unocal Station No. 6981, 4707 <br /> Pacific Avenue, Stockton, California. <br /> Mr Yemane <br /> This report summarizes the sampling and operational data for the vapor extraction system <br /> (VES) at the subject site from October through December 1996 This report also contains <br /> a response to San Joaquin County Public Health Services (SJCPHS) letters dated September <br /> 18, 1996, and January 3, 1997 Location of the subject site is shown on Figure 1 The <br /> current station configuration is shown on Figure 2 <br /> Fourth Quarter 1996 Activities <br /> Field activities conducted at the subject site during the fourth quarter 1996 are discussed <br /> below GeoStrategies (GSI) Field Methods and Procedures are attached <br /> The VES effluent vapor stream was sampled by Gettler-Ryan Inc (G-R) on October 28, <br /> November 21, and December 20, 1996 The samples were analyzed for TPHg and BTEX <br /> at Sequoia ,Analytical in Redwood City, California (ELAP #1210) Copies of the <br /> laboratory reports and chain-of-custody documents are attached <br /> Between September 25 and December 20, 1996 the VES operated approximately 623 hours <br /> (26 days), or 30% of the time The VES continues to have problems flaming out, and <br /> repeated efforts to correct this issue in the field have not resolved the problem. Soil vapor <br /> was extracted from wells VW-2, VW-4, and VW-5 during the fourth quarter 1996, as field <br /> monitoring indicated these wells had the highest hydrocarbon concentrations. During the <br /> fourth quarter 1996, the VES extracted and treated approximately 434 pounds of TPHg and <br /> 1 pound of benzene VES analytical data for the quarter are summarized in Table 1, and <br /> operational data are summarized in Table 2 <br /> First Quarter 1997 Scheduled Activities <br /> MPDS Inc will monitor and sample groundwater wells at the site, and will submit the <br /> quarterly groundwater monitoring and sampling report to the appropriate agencies GSI <br /> • <br /> 4955 20-1 <br /> 3164 Gold Camp Drive, Suite 240 • Rancho Cordova, CA 95670 • (916) 631-1314 • Fax (916) 631-1317 <br />