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2 . 0 GROUNDWATER FLOW DIRECTION AND GRADIENT On December 18, 2000, ASE 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 002-feet of free-floating hydrocarbons The free-floating hydrocarbons are 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 Groundwater elevation (potentiometric surface) contours are plotted on Figures 2, 3 and 4 Groundwater in the shallow zone (less than 20-feet bgs) has historically shown a northern flow ASE installed a "pump and treat" interim remediation system in September 2000 to influence the offsite downgradient flow pattern in the shallow zone Based on t h e groundwater elevations taken on December 18, 2000, there appears to b e a "coning effect" occurring in the northern portion of the site Although . the historic gradient has been to the north, groundwater now appears t o be flowing toward the recovery wells Groundwater in the middle zone (55-70-feet bgs) appeared to flow to t h e south with a gradient of approximately 0 0016-feet/foot, which is consistent with previous findings The groundwater flow in the deep zone (greater than 100-feet) appeared to flow to the northeast at a very flat gradient of approximately 0 0001-feet/foot Potentiometric surface differences in wells adjacent to each other but screened in different zones (such as monitoring wells MW-6, MW-7 and MW-8) show a decreasing hydraulic head with depth, suggesting the potential for downward groundwater flow 3 . 0 GROUNDWATER SAMPLE COLLECTION On December 18 and 19, 2000, ASE 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, t h e 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 Frank's One Stop Quarterly Report — December 2000 Sampling -2-