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1 01 June 1999 AGE-NC Project No 95-0137 Page 9 of 26 the concentrations of extracted vapor have decreased and stabilized after a certain period of operation, confirmation borings are drilled to collect soil samples for quantitative analysis in the laboratory to evaluate the effectiveness of the remediation effort and to assess the need for continued ' remediation ' 5 14 Soil Vapor Extraction Pilot Test A vapor extraction feasibility test was performed at the site On 16 November 1998, an 8-hour soil tvapor extraction (SVE) test was initiated at the site This pilot test was performed to provide SVE data prior to initiation 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 of the extracted hydrocarbon vapors Procedures The test was initiated at 8 30 am and continued for approximately 8 hours An induced vacuum potential was applied to the casing of vapor well VW-I for approximately two hours At that point an excessive quantity of water was observed in a 55-gallon knock-out drum used to collected ' moisture produced by the extraction process Due to the excessive volume of water being extracted from VW-1, the test was interrupted to disconnect the SVE unit from VW-1 and to reconnect onto the casing of vapor well VW-2 The test was reinitiated for approximately six additional hours ' The vacuum-induced pressure reduction was monitored at surrounding observation points (MW-1, MW-2 and MW-3, MW-4 and vapor well VW-1 and VW-2) with air tight well caps pre-connected ' with Magnehelic vacuwn 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 photo-ionization ' detector(PID Microtip model 1000 calibrated to isobutylene) was used to measure organic vapor (OV) concentrations The organic vapor concentrations, the induced vacuum potential at the observation points, extracted soil gas flow rate, and RPMs of the SVE unit were measured at 0 5- hour intervals and logged on field sheets Pilot test data are summarized in Table 6 Sampling and Analyses A total of four soil gas/vapor samples were collected during the pilot test ' Soil gas/vapor samples were collected at two-hour intervals from the inlet of the extraction well to measure hydrocarbon concentrations in the extracted gas/vapor The samples were collected in Tedlar bags using an air pump Samples were transported in a chilled container under chain-of- custody to Mc Campbell Analytical, Inc (MAI), a California Department of Health Services (DHS)- certified laboratory Each sample was analyzed within 72 Hours for TPH-g, BTE&X and oxygenated fuel additives (methyl tertiary butyl ether[MTBE],tertiary butyl alcohol [TBA]), di-isopropyl ether [DIPE],ethyl tertiary butyl ether [ETBE] and tertiary amyl methyl ether [TAME] in accordance with Advanced GeoEmironmentai,Inc