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The sampler proceeded to purge well volumes of groundwater from the well using a submersible electric purging pump (a calculation was done for each well following sounding measurements) Between each well volume purge, conductivity, pH, and water temperature readings were obtained and noted on the attached groundwatersampling information sheets Once these readings stabilized after two consecutive purge volumes aquifer water is assumed to be entering the well When the well recovered to about 80% of the initial water level, the sample was collected Purge water was stored on-site in drums The well sampling information sheets containing data on temperature, conductivity, pH, depth to water, and well volumes purged are attached The groundwater sample was collected with a new disposable bailer The groundwater sample was then poured with minimum cavitation into the appropriate, laboratory prepared sample containers leaving no headspace The sample container was then immediately capped, labeled and placed in a chilled ice chest for shipment to Priority Environmental Laboratory in Milpitas, California (a State Certified Testing Lab) under chain-of-custody documentation Groundwater Contour Map and Flow Gradient A groundwater contour map was prepared for the data listed in Table 1 above (see Figure 1) . Groundwater elevation contours were plotted to a known datum The groundwater flow direction was to the north-northeast under a calculated gradient of 0 003 The flow direction is consistent with historic observed trends, and remains relatively flat However, recent heavy precipitation events and regional flooding may cause local flow influences in the future Chemical Analytical Methods and Results Three groundwater samples were analyzed using EPA Methods 5030/8015 and 602 for Total Petroleum Hydrocarbons as Gasoline (TPHG), Benzene, Toluene, Ethylbenzene and Xylene (BTEX) and Met hyl-tert-butyl-ether (MTBE) The analytical results of the groundwater samples are attached and listed below (see Table 2), Table 2- Groundwater Chemical Data Well Date TPHG Benzene Toluene Ethylbenzene Xylene MTBE �- } {;L43s/ No. Sampled -----------------------------ug/I ------------------------------- ---- —�� MW-1 3/28/96 ND ND ND ND ND NA 7- MW-1 MW-1 6/27/96 280 0 7 06 2 4 91 NA Z7 q I� MW-1 9/23/96 ND ND ND ND ND NA 6 3 `r �2 MW-1 12/19/96 ND ND ND ND ND ND 7�b� t f D +� 40, Mr Ed's Project Na 4090-P Page 2