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R Groundwater Elevation Data Depth to groundwater was obtained from the existing groundwater monitor wells at the site using a water level indicator graduated to 0 01 foot The depth to groundwater measurement was converted to a groundwater elevation for each well and used to construct a groundwater elevation contour map (Figure 2),and calculate the local groundwater flow direction and hydraulic gradient Groundwater at the site was measured at depths between 67 07 to 75 14 feet below ground surface (bgs) The groundwater potentiometric surface elevation averaged approximately 28 87 feet bgs during this monitoring event The groundwater elevation has increased approximately 0 83 feet since the last sampling event in August 2000 The groundwater flow direction during this reporting period is toward the southwest with a hydraulic gradient of approximately 0 08 ft/ft A summary of data regarding groundwater levels measured through November 3, 2000 is presented in Table 1 Copies of field observations documenting work performed at the site are presented in Attachment I Groundwater Analytical Results The distnbution of groundwater sample analytical results obtained from monitor wells at the site on November 4, 2000, is presented on Figure 3 and summarized in Table 2 TPHg and BTEX were present at detectable concentrations in three of the nine samples submitted for analysis The highest concentration of petroleum hydrocarbons is in the vicinity of monitor well MWA TPHg concentrations in groundwater samples ranged from 277 micrograms per liter(ug/L)to monitor well MW-5,to less than detectable levels in samples collected from monitor wells MW-2,MW-3,MW-6 through MW-8, and MW-10 Benzene concentrations ranged from below the laboratory method detection limit in monitor wells MW-2,MW-3,MW-6 through MW-8, and MW-10,to 24 9 ug/L in MW-4 MTBE concentrations in groundwater samples ranged from below the laboratory method detection limit in monitor wells MW-4, MW-7 through MW-10, to 2 2 ug/L in a sample collected from monitor well MW-5 Attachment U contains photocopies of the laboratory analytical report and the chain-of-custody form Approximately 0 75 feet of liquid phase hydrocarbon (LPH) was detected in MW-1 during this monitoring event The LPH is currently being removed from MW-1 by hand barking methods and the use of a passive, down-hole petroleum skimmer on a weekly basis The LPH thickness has decreased sigmficantly in MW-1 since it was first observed in February 2000 A total of approximately 40 gallons of LPH has been removed from MW-1 since its detection in February 2000 Purge Water Purge water generated during groundwater purging is currently contained on-site in Department of Transportation rated 55-gallon drums and will be removed to a disposaVrecychng facility during January 2001 SITE REMEDIATION Construction of a soil and groundwater remediation system was completed at the site in December 1999 The remediation system consists of seven soil vapor extraction (SVE) wells (W-1, W-3 C 1Time OIN.pckefardQ400 2 SECOR 077 41731 a03 February 1 2001