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Upon arriving at the site with precleaned equipment, the sampler measured the depth to water, sounded the well and checked for the presence of free phase product The sampler proceeded to purge the well (a calculation was done for each well following sounding measurements) of groundwater using the disposable bailer The well was then allowed to re-charge Between each well volume purge, conductivity, pH, and water temperature readings were obtained and noted on the Groundwater Sampling Information Sheet (see Appendix A) Once the stabilization of the readings were noted, the sample was collected from the well Purge water was stored on-site in drums The well sampling information sheet containing data on temperature, conductivity, pH, depth to water, and well volumes purged can be found in Appendix A Once the well recovers to about 80% of the initial water level measurement, a new disposable bailer was used to obtain the groundwater sample which was placed into the appropriate, laboratory prepared sample containers leaving no headspace, and immediately placed on ice for shipment to Priority Environmental Labs in Milpitas, California (a State Certitied Testing Lab) under proper chain-of-custody documentation The chain-of-custody and the Laboratory Analysis Results can be found in Appendix B LABORATORY FINDINGS Three groundwater samples were analyzed for Total Petroleum Hydrocarbons as Gasoline (TPHG) and Benzene, Toluene, Ethylbenzene and Xylene (BTEX) using EPA Methods 8015 and 8020 respectively The analytical results of the groundwater samples revealed the following (see Table 2), Table 2 Groundwater Analytical Results Well Depth to Grndwater Number Date Water Elevation TPHG B T E X MW-1 12/05/94a 916 4024 48,000 2100 510 1900 3000 (49 40) 4/3/95 902 4024 82,000 380 150 310 620 MW-2 12/06/94a 1001 4051 <?-W ND ND ND ND (50 52) 4/3/95 928 4032 ND ND ND ND ND MW-3 12/09/94a 9 46 4032 X200 ND ND ND ND (49 78) 4/3/95 884 4051 ND ND ND ND ND Depth to water measured in feet below top of PVC casing NC - Not Calculated Groundwater elevation measured in feet above Mean Sea Level ND - Not Detected Groundwater elevation equals surveyed top of PVC casing elevation minus depth to water (49 40) Surveyed elevation of the top of PVC casing TPHG - Total petroleum hydrocarbons as gasoline results in ug/1, parts per billion (ppb) BTEX - Benzene, Toluene, Ethyl-Benzene, X}lene results in ug/L parts per billion (ppb) a) Samples not analyzed at RWQCB detection limit for this monitoring episode M&M Automotive April 1995