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After collecting the above measurements on July 22, 1994, MW-1 and MW-2 were purged and MW-2 was sampled. MW-1 was purged dry and recovered at much less than 0.1 gallons per hour. MW-2 was purged a minimum of three well volumes (24 gallons) with a disposable bailer prior to sampling. Groundwater samples were collected using a new disposable bailer Two samples (QA/QC split) were collected to allow comparison of laboratory data. Each sample was collected in three 40m1 VOA bottles supplied by the analytical laboratory. After filling, each bottle was inverted and checked for headspace, labeled, logged on a chain-of-custody, and immediately placed in an iced cooler GROUNDWATER Using the depth to groundwater measurements collected on July 22, and September 20, 1994 and the surveyed locations and elevations supplied by Tom O Morrow, Inc , I calculated the groundwater gradient. The depth to groundwater for MW-3 was corrected for the presence of an immiscible layer using a relative density of 0 8 and rounding to two significant figures. Based on these measurements, the gradient would appear to be to the southeast at approximately 8 percent Based on the inability for MW-1 to recover after purging and the extreme difference in depth to groundwater measurements between MW-1 and the remaining wells, it is probable that the calculated gradient is not indicative of actual site conditions ANALYTICAL One water sample was delivered to Western Environmental Science and Technology (WEST) in Davis, California at the end of the sampling day. The second (split) was delivered to Sparger Technology, Inc in Sacramento on July 25, 1994 Both laboratories are certified by the State of California Department of Health Services (DoHS) for the requested analyses. Both of the water samples were analyzed for TPHg and BTEX by EPA Method 5030/8015M Both laboratories reported that the water sample contained TPHg and BTEX above the reporting limits. Although both laboratories reported significantly lower concentrations of TPHg and BTEX than were reported in the February sampling (analyzed by WEST), the nearly 3x difference between the laboratory results for the July sampling is even more notable. The analytical results are summarized on Table 2. A copy of both laboratory reports are attached. TABLE 2 Groundwater Analytical Results (ug/1) Laboratory Location Date TPHg Benzene Toluene Ethylbenzene Xylenes WEST MW-2 2/7/94 4,100 670 564 25 310 WEST MW-2 7/22/94 520 61 85 11 69 Sparger MW-2 7/22/94 2,700 300 390 32 140