Laserfiche WebLink
- 26 <br /> 7-Eleven/Stockton <br /> November 1989 <br /> r GROUNDWATER REMEDIATION SYSTEM <br /> During this three month reporting period, groundwater was <br /> extracted from recovery well RW-1 only. Pumping was maintained <br /> in RW-1 at a rate of 0.6 - 1.0 qpm. The areas being influenced <br /> by pumping are illustrated on the previously referenced <br /> groundwater-gradient maps (Figures 5, 6, and 7) . <br /> Groundwater extracted from the pumping wells is treated <br /> through an air-stripping tower prior to discharge to the sanitary <br /> sewer system. Every two weeks, laboratory analyses are conducted <br /> on the influent to and effluent from the air-stripping tower o <br /> the presence of concentrations of BTEX and TPH-as-gasoline in <br /> order to verify compliance with requirements imposed by the <br /> Stockton Municipal Utilities District and the San Joaquin County <br /> Air Pollution Control District. The influent and effluent <br /> concentrations of BTEX and TPH-as-gasoline are tabulated on Table <br /> 2 (Appendix A) and the laboratory results are included in <br /> Appendix c. The air-stripping tower effluent sample results were <br /> below the laboratory method detection limits (MDL) for BTEX and <br /> TPH-as-gasoline during each sampling interval conducted during <br /> this reporting period. In addition to the BTEX and TPH-as- <br /> gasoline analyses, the air-stripping tower effluent is sampled <br /> and analyzed once a month for the presence of metals. Laboratory <br /> analyses are performed for the presence of lead, cadmium, <br /> chromium, copper, nickel, and zinc. For all three sampling <br /> rounds, the sample analyses results indicate that the levels of <br /> these metals in the discharge were below the specified discharge <br /> limits. These results document that the air-stripping system is <br /> not exceeding the permitted discharge requirements. The results <br /> .. of the analyses for metals are tabulated on Table 5 (Appendix A) <br /> and the laboratory results are included in Appendix C. <br /> �3 Gltul'\E�1'11t:k <br /> Tt:olmll-­A.IM <br />