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I 20 March 2006 AGE-NC Project No . 03- 1071 Page 9 of 13 3 .4, EXTRACTED WATER ANALYTICAL RESULTS The results of the laboratory analysis detected TPH-g in both grab samples at concentrations as high as 61 ,000 micrograms per liter (µg/1). All BTEX compounds were detected in both grab ground water samples at A concentrations as high as 9,900 gg/l benzene, 23,000 µg/1 toluene, 2,500 µg/l ethylbenzene, 18,200 xylenes, from the 09 : 15 _interval sample. Fuel oxygenated compounds MTBE, and 1 ,2-DCA were detected in the first sample M14yzed at maximum concentrations of 220 pg/1 and 230 µg/1 , respectively. The laboratory reports (CT214- 0508186) and chain-of-custody forms are presented in Appendix G. 4.0 SOIL VAPOR EXTRACTION (SVE) PILOT TEST On 23 August 2005, an 8-hour SVE pilot test was conducted at the site using vapor well VW-3 , screened from 15 feet bsg to 35 feet bsg as the extraction well. The pilot test was performed to provide SVE data prior to installation of a full scale remediation system. The test was conducted using a VACLEEN 1000 SVE system, manufactured by Environmental Techniques. The VACLEEN unit consists of a positive-displacement blower, driven by an internal combustion (IC) engine. Propane was used as a supplemental fuel source to start the engine and maintain performance. Hydrocarbon vapor was destroyed as part of the internal combustion process . Emissions from the engine were routed through two catalytic converters to maximize the destruction rate ofthe extracted hydrocarbon vapors. All field work procedures and reporting requirements are in accordance with guidelines issued by the Central Valley Region of the Regional Water Quality Control Board (CVRWQCB) for subsurface investigation of underground storage tank (UST) system sites. 4. 1 . SVE PILOT TEST PROCEDURES The pilot test was initiated at 0840 am and continued for approximately 7 hours, at which time the test was terminated due to stabalization. An induced vacuum potential was applied to the casing of vapor well VW-3 . The vacuum-induced pressure reduction was monitored at surrounding observation points (VW- 1 , VW-2, VW-4, and MW-2) with air-tight well caps pre-connected with Magnehelic vacuum gauges fitted to each observation well. A sample port was tapped into the PVC near the wellhead and a portable organic vapor meter equipped with a PID (PID : Microtip model 1000 calibrated to isobutylene) was used to measure organic vapor (OV) concentrations . The organic Advanced GcoEnvironmentnl, Inc.