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The purged sampler ed well volumes of groundwater from the well using the disposable <br /> p P 9 <br /> bailer (a calculation was done for each well following sounding measurements) The <br /> well was then allowed to recharge Between each purge of the well the volume, <br /> conductivity, pH, and water temperature readings were obtained and noted on the <br /> attached Groundwater Sampling Information Sheets presented as Appendix A Once <br /> these readings stabilized after at least two consecutive purge volumes (aquifer water <br /> is assumed to be entering the well), and the well recovered to about 80% of the Initial <br /> water level, the sample was collected from the well Purge water was stored on-site in <br /> drums A new disposable bailer was used to obtain the groundwater sample that was <br /> placed with minimum cavitation Into the appropriate, laboratory prepared sample <br /> containers leaving no headspace The sample container was Immediately capped <br /> and placed In a chilled Ice chest for shipment to Priority Environmental Laboratory in <br /> Milpitas, California (a State Certified Testing Lab) under chain-of-custody <br /> documentation <br /> Groundwater Contour Map and Flow Gradient <br /> A groundwater contour map was prepared for the data shown in Table 1 above (see <br /> Figure 1) Groundwater elevation contours were plotted to a known datum from the <br /> measurements The groundwater flow direction was to the north under a calculated <br /> gradient of 0 002 The groundwater flow direction is consistent with historic observed <br />• trends, and remains relatively flat <br /> Chemical Analytical !Methods and Results <br /> Three groundwater samples were analyzed using EPA Methods 5030/8015 and 602 <br /> for Total Petroleum Hydrocarbons as Gasoline (TPHG), Benzene, Toluene, <br /> Ethylbenzene and Xylene (BTEX) The chain-of-custody and the Laboratory Analysis <br /> Results are attached The analytical results of the groundwater samples revealed the <br /> following (see Table 2) <br /> Table 2 Groundwater Analytical Results <br /> Well Date TPHG Benzene Toluene Ethylbenzene Xylene <br /> No Sampled ----- ug/l ------------- <br /> MW-1 3128196 ND NO ND NO ND <br /> MW-1 6127/96 280 0 7 0 6 2 4 9 1 <br /> MW-1 9/23196 ND NO ND NO ND <br /> MW-2 3128/96 12,000 8 0 5 0 7 7 20 <br /> MW-2 6/27196 4,900 7 2 4 8 21 25 <br /> MW-2 9/23/96 4,500 5 9 2 8 15 14 <br />