ARCHIVED REPORTS_XR0007391 CASE 1

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k'9 KLEINFELDER 6 CONCLUSIONS AND RECOMMENDATIONS ' 61 CONCLUSIONS ' Groundwater elevations ranged from a maximum of 1 81 feet above mean sea level (msl) at MW-4 to 0 75 feet above msl at MW-2 Depth to water was measured at approximately 38 01 to ' 38 98 feet bgs Groundwater flow was towards the southwest with an approximate gradient of 0 003 ft/ft ' No product or sheen was observed from groundwater from perimeter monitoring wells MW-2, MW-3, and MW-4 An approximate one quarter inch of floating product and a strong petroleum- like odor was noted in the groundwater from monitoring well MW-1 ' TPH-D and TPH-G were detected in the groundwater sample collected from MW-1, located approximately 10 feet down-gradient of the UST area TPH-D was detected at concentrations of t13 mgll and TPH-G at 2 8 mg/l BTEX constituents were not detected above the laboratory reporting limits in the groundwater sample collected form MW-1 None of the requested petroleum constituents were detected in the groundwater samples collected from the down- gradient monitoring wells, MW-2 and MW-3, nor from the upgradient well MW-4 ' Based on the information obtained, it is Kleinfelder's opinion that the groundwater contaminant plume is located in the vicinity of MW-1 and the existing UST area, and is apparently contained within perimeter monitoring wells MW-2, MW-3 and MW-4 A petroleum product layer has ' been detected on the surface of groundwater in monitoring wells MW-1 over the last six quarterly sampling events at thicknesses ranging from a film (<0 01 feet) to approximately 33 feet (4 inches) Dunng this Fourth Quarter 2003 sampling event, product was detected in MW-1 ' at an approximate thickness of 0 02-feet (approximately 1/4 inch) Floating product was not detected in the initial five groundwater sampling events beginrung in June 2000 through June 2002 The appearance of floating product in MW-1 has been observed since September of 2002 Kleinfelder has noted a general decrease in water levels over time, which may be a contributing ' factor of floating product occurring in monitoring well MW-1 Groundwater elevations from MW-1 in the initial four groundwater sampling events ranged from 4 55 to 6 92 feet The groundwater elevation of the fifth sampling event was 3 18 feet Over the past six sampling ' events groundwater elevations in MW-1 have ranged from —0 11 to 2 94 feet Similar trends were noted in the other three perimeter monitoring wells over the past sampling events 1 28209 T / T04R157 Page 9 of 11 03 S S OO 2104 Klemfelder, Inc February 3, 2004