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I 1 CAMRIA i Grab groundwater samples were collected from three to four discrete intervals in each of the CPT borings. No TPHg or BTEX were detected in any of the grab groundwater samples collected. MTBE was detected in grab groundwater samples collected from borings CPT-11 and CPT-12 only at concentrations up to 3,010 ppb and 27 ppb, respectively. Grab groundwater sample results are summarized in Table 3. Investigation activities were reported in Cambria's April 16, 1999 Monitoring Well and CPT Investigation Report. 1999 Pump Test: In May 1999, Cambria conducted a step-drawdown pump test and a constant- rate pump test on extraction well EW-1. Based on test results, Cambria calculated an estimated hydraulic conductivity at the site of approximately 3.2x10'1 centimeters per second (cmisec). Drawdown was observed in wells EW-2 and MW-1, located approximately 33 feet and 43 feet from pumping well EW-1, respectively. Very little drawdown was observed in well MW-2, located approximately 80 feet from well EW-1, and no drawdown was observed in well MW-3, located approximately 110 feet from well EW-1. Results of the pump test were reported in Cambria's July 7, 1999 Pump Test Investigation Report. 2000 GWE System Operation: In March 2000, a GWE system was installed at the site extracting groundwater from well EW-1. The GWE system operated until July 2001, when it was shut-down due to low influent groundwater concentrations. Shut-down was approved by the San Joaquin County Environmental Health Department. An estimated 2,295,500 gallons have been extracted at the site from both purging and GWE activities. An estimated 1.8 pounds of total hydrocarbons and 15.2 pounds of MTBE have been removed at the site. GWE activities were described in quarterly monitoring reports submitted for the site. I qqy vgg'lz 1,5 2000 Well Installation: In October Cambria installed one groundwater monitoring well pair (MW4A and MW-4B), and two nested groundwater monitoring wells (MW-5A/B and MW-6A/B). The "A" wells screen from approximately 70 to 75 fbg, and the "B" wells screen approximately 45 to 50 fbg. No TPHg, BTEX, or MTBE was detected in soil samples collected from the monitoring wells. Soil analytical results are summarized in Table 1, and investigation activities were reported in Cambria's February 9, 2000 Well Installation Report. 2001 Soil Vapor Extraction (SVE) Feasibility Test: In April 2001, Cambria performed a SVE feasibility test on wells EW-1, MW-4B, and MW-1 at the site. The maximum distance that vaCimm inflm-nra was nntPH fhlrina the tf-m wac RO fe..et. anted in well MW-7 dwinv IVF, from well EW-1. Except for 3.87 parts per million by volume (ppmv) TPHg and 0.408 ppmv MTBE detected in the influent sample collected from well MW-1, no TPHg, BTEX, or MTBE were 0324 4