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I i Table 1 Monitoring Well Water Levels, con't Well Date Well Depth to Casing Water Floating No Sampled Depth Water Elev Elev Product (ft) (ft) (MSL ft)' (MSL ft) MW-9^ 8/20197 15 95 8 33 48 28 39 95 None MW-9^ 12/12/97 15 95 800 ----- 40 28 None MW-9^ 3/31/98 13 18 723 ----- 41 05 None MW-9^ 6/30/98 13 18 7 49 ----- 41 79 None " Casing elevation data from Evax Technologies, Site Investigation Report, April 7, 1992 ^ Casing elevation data from Triple "E" Engineering and Surveying, August 14, 1997 The sampler proceeded to purge well volumes of groundwater using a submersible electric purging pump (a volume 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 groundwater sampling 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 Chromalab, Inc in Pleasanton, California (a State Certified Testing Lab) under chain-of-custody documentation Groundwater Contour Map and Flow Gradient A groundwater contour map to a known datum was prepared for the data listed in Table 1 above (see Figure 1) The groundwater flow direction was to the north-northwesterly under a calculated gradient of 0 0032 The flow direction is consistent with historic observed trends, and remains relatively flat Overall groundwater levels appear to have declined slightly from the previous quarter I A large groundwater mound has appeared at MW-9 This well is very near a large agricultural line and strongly suggests leakage from either that pipeline or another subsurface water source in the near vicinity of MW-9 Chemical Analytical Methods and Results Nine groundwater samples were analyzed using EPA Methods 503018015, 602 and 8260 f o r Total Petroleum Hydrocarbons as Gasoline (TPHG), Benzene, Toluene, Ethylbenzene and Xylene (BTEX) and fuel oxygenates including Methyl-tert-butyl-ether (MTBE) The analytical results of the groundwater samples are attached and listed with historic data below (see Table 2), 1 Page 3