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JI Mr Martin Harris Page 2 of 3 • site wells, analyzing samples for total petroleum hydrocarbons as gasoline (TPHg) benzene, toluene, ethylbenzene, total xylenes (BTEX), oxygenated gasoline additives, 1,2-dichloroethane (1,2-DCA), and ethylene dibromide (EDB) Groundwater Monitoring and Sampling Monitoring wells MWI through MW4 were monitored and sampled on June 30, 2003 Groundwater elevations were calculated by subtracting the measured depth to groundwater in each well from the respective wellhead elevation The depth to groundwater in the wells ranged from 6 56 to 7 44 feet below the tops of the well casings (btoc) The potentiometnc surface fell an average of 0 62 feet between March 7, 2003 and June 30, 2003 Groundwater generally flowed to the west at a relatively flat gradient of 0 0004 ft/ft, or approximately 2 2 ft/mile A potentiometric surface map generated from the June 30, 2003 monitoring data is shown on Figure 2 Groundwater monitoring data are summarized in Table 1 Monitoring data sheets are included in Attachment A Prior to sampling, monitoring wells MWI through MW4 were purged of at least three well casing volumes The physical parameters of temperature, pH and electrical conductivity were measured during the purging process Groundwater samples were collected after the physical parameters stabilized and groundwater in the wells recovered to at least 80% of pre-purged levels The samples were placed into an ice chest refrigerated to approximately 4°C and transported to Argon Laboratories (ELAP #2359) under chain of custody protocol Well purge logs are included in Attachment A Groundwater Analytical Results Groundwater samples were analyzed for the presence of TPHg, BTEX, and oxygenated gasoline additives (including the lead scavengers 1,2-DCA and EDB) using EPA methods 8015B, 802IB, and 8260B,respectively TPHg was detected in wells MWI and MW2 at concentrations of 350 parts per billion (ppb) and 290 ppb respectively No TPHg was detected in wells MW3 or MW4 Benzene was detected in well MW2 at a concentration of 0 8 ppb No benzene was detected in wells MW 1, MW3, or MW4 Ethylbenzene and xylenes were detected in will MWI at concentrations of 0 9 ppb, and 13 ppb, respectively No toluene was detected in well MWI No toluene, ethylbenzene, or xylenes were detected in wells MW2, MW3, or MW4 Methyl-tert butyl ether (MTBE) was detected in wells MWI and MW3 at concentrations of 10 ppb and 4 4 ppb, respectively No MTBE was detected above the method detection limit of 2 0 ppb in wells MW2 or MW4 No other oxygenated gasoline additives or lead scavengers were detected in any site well Analytical results are summarized in Table 2 Attachment B contains the laboratory report and chain of custody documentation G 1GRQUNDZE1Tuf313oy1RLportslQMRl2Qhf2DO3 doc