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2 . 0 GROUNDWATER FLOW DIRECTION AND GRADIENT On June 15 and 16, 2000, ASE associate geologist Ian Reed measured the depth to water in each site groundwater monitoring well using an electric water level sounder The surface of the groundwater was also checked for the presence of free-floating hydrocarbons or sheen using an oil/water interface probe and a product thickness bailer Monitoring well MW-5 contained 0 02-feet of free-floating hydrocarbons The free-floating hydrocarbons appeared yellow and is believed to be gasoline A hydrocarbon sheen was present on the groundwater surface in monitoring well MW-6 No free-floating hydrocarbons or sheen were observed in any other site monitoring well Groundwater elevation data is presented as Table One Due to the presence of free-floating hydrocarbons in monitoring wells MW-5 and MW-6, ASE has been measuring the thickness of the free- floating hydrocarbons in these wells once a month Any accumulated product in these wells is then removed with a bailer The free-floating hydrocarbon thickness measurements are tabulated in Table One Groundwater elevation (potentiometric surface) contours are plotted on Figures 2, 3 and 4 On June 15, 2000, groundwater in the shallow zone (less than 20-feet bgs) appeared to flow to the north beneath the site with a gradient of approximately 0 0016-feet/foot This groundwater flow direction is generally consistent with previous findings Groundwater 1 n the middle zone (55-70-feet bgs) appeared to flow to the south, toward the on-site drinking water well, with a gradient of approximately 0 0143- feet/foot 143- feet/foot A potentiometric surface map for the deeper zone (greater than 100-feet bgs) could not be prepared do to the fact that there are only two (2) deep wells currently installed at the site 3 . 0 GROUNDWATER SAMPLE COLLECTION On June 15 and 16, 2000, ASE associate geologist Ian Reed collected groundwater samples from the site wells for analysis Monitoring well MW-5 was not sampled due to the free-floating hydrocarbons present in that well Prior to sampling, the site monitoring wells were purged of four well casing volumes of groundwater using pumps and/or dedicated bailers The pH, temperature and conductivity of the purge water were monitored during evacuation, and samples were not collected until these parameters stabilized Samples were collected from the wells using pre- cleaned dedicated polyethylene bailers The groundwater samples were decanted from the bailers into 40-m1 volatile organic analysis (VOA) vials, Frank's One Stop Quarterly Report — June 2000 Sampling -2-