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Mr Jeff Wong Page 2 of 4 • installed in the well on May 19, 2003 Table 1 summarizes the measured product thickness and volume removed from well MW 1 since August 16, 2001 Attachment A contains copies of field logs related to product monitoring and removal during the reporting period 2.2 Groundwater Monitoring and Sampling A Ground Zero technician monitored water levels in all site wells, and collected samples from monitoring wells MW1 through MW9B on June 17 and 18, 2003 Groundwater elevations were calculated by measuring the depth to groundwater in each well and subtracting the measured depth from the respective well head elevation The measured depth to groundwater below the tops of the well casings (btoc) in the shallow monitoring wells ranged from 63 45 feet in well MW1 (corrected for the presence of free product) to 64 44 feet in well MW5 (completed at approximately 2 25 feet above ground surface) Groundwater elevations in the shallow aquifer beneath the site ranged from 31 54 feet (MW2) to 31 87 feet (MW5) below mean sea level Groundwater levels in shallow monitoring wells MW1 through MWS fell an average of 0 11 feet between March 12, 2003 and June 17, 2003 The groundwater level in well MW9B, which was completed in a deeper aquifer, was measured at approximately 63 83 feet btoc on June 17, 2003, and fell 0 47 feet during the same period Table 2 summarizes groundwater elevations in site monitoring wells The measured groundwater flow direction in the shallow aquifer was irregular beneath the site on June 17, 2003 The groundwater gradient across the site averaged approximately 0 0031 feet per foot (approximately 16 feet per mile) Figure 2 presents a potentiometric surface map generated using the March 12, 2003 monitoring data An experienced Ground Zero technician purged at least three well casing volumes of water from monitoring wells MW1 through MW9B prior to sampling the wells During the purging process, the technician measured the temperature, pH and electrical conductivity of the water Samples were collected after the physical parameters stabilized and water levels in the wells recovered to at least 80% of their pre-purged levels The samples were temporarily stored in an ice chest refrigerated to a temperature of approximately 4°C and delivered under chain of custody protocol to Argon Laboratories (ELAP 42359) for analysis Purged groundwater was contained in appropriately labeled DOT-approved 55-gallon drums in accordance with 49 CFR part 172 and 40 CFR part 262 Copies of field data sheets and purge logs are included in Attachment B 3.0 GROUNDWATER ANALYTICAL RESULTS Argon Laboratories analyzed the groundwater samples for total petroleum hydrocarbons as gasoline (TPHg) using EPA 8015B, benzene, toluene, ethylbenzene, and total xylenes (BTEX) using EPA 8021B, and oxygenated gasoline additives, ethylene dibromide (EDB) and 1,2- dichioroethane (1,2-DCA)using EPA 8260B TPHg was detected in wells MW1, MW2, MW3, and MW4 at concentrations of 230,000 parts per billion (ppb), 510 ppb, 90 ppb, and 220 ppb TPHg, respectively No TPHg was detected in wells G1GROUNDZE\TULEBURG\ReportslQMR1200312QM2003 doe