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' monitoring gradient data is included in Table 3. The PHS/EHD further stated that after gradient confirmation "additional monitoring wells may have to be installed to ensure that a down gradient well is provided. Currently MW-3 is upgradient of the tank pit and is the well with the highest contamination in the groundwater."However, subsequent groundwater flow direction calculations have shown MW-3 to be down gradient of the former UST's. 3.0 PROCEDURES Monitoring g Well Purging � g On June 22 and July 26, 1994, the water levels in each well were measured relative to the top of the casing using a Solinst water level meter (Table 3). No free hydrocarbon product ' was observed in any of the wells. After water levels were measured on June 22, a bailer was used to remove standing water from each well to stabilize temperature, pH and conductivity (Appendix A). Groundwater ' parameters were measured at one-gallon intervals using an ICM water analyzer.The purge water was stored in 55-gallon drums on-site. Seven gallons of water were removed from MW-2. However, MW-1 was bailed dry after removing only three gallons of water. Less than one gallon of waterLwas removed from MW- 3 before it went dry. Monitoring well MW-3 showed only 6% recharge after one hour. 3.2 Sample Collection and Analysis After each well was stabilized, water samples were collected using disposable plastic bailers. Samples from MW-1 and MW-2 were collected on June 22, 1993; because of poor recharge, the sample from MW-3 was collected on June 23, 1994. Each sample was collected in three 40-m1 EPA vials. The samples were then placed in a ' chilled container and transported under chain-of-custody procedure to Alpha Analytical Laboratories in Ukiah, California. Each sample was analyzed for TPH as stoddard solvent and-BTE&X in accordance with EPA methods GCFID/5030 and 602, respectively. 1 4.0 FINDINGS ' 4.1 Groundwater Elevation and Gradient The elevation of groundwater in each well was calculated by subtracting the groundwater depth from the surveyed casing elevation (Table 1). The average depth to groundwater at the site in June 1994 was 41.32 feet; the average depth to groundwater in July 1994 was 42.11 feet. This represents more than a three-quarter foot drop in groundwater between June and July 1994. This decrease in groundwater depth is consistent with seasonal a.obp�A.ad seNioea.I.c. 6 Sk—M e..w QR3X9cei.a -