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G� 08 October 2003 AS AGE-NC Project No. 98-0504 Page 2 of 7 2.3. UNDERGROUND STORAGE TANK REMOVAL Two USTs, dispenser island and associated piping were removed from the site on 22 September 1998. Four samples were collected beneath the USTs, one sample was collected beneath the dispenser area and three laboratory-composited soil samples were collected from the excavated soil. Methyl tertiary butyl ether (MTBE) and tertiary butanol (TBA) were detected in soil samples collected from beneath the USTs and dispenser island at concentrations up to 39 parts per million (ppm);total petroleum hydrocarbons quantified as gasoline(TPH-g)were detected at concentrations up to'1,400 ppm; and volatile aromatics(benzene,toluene,ethyl benzene and xylenes: BTEX)were detected at concentrations up to 190 ppm. Approximately 200 tons of soil were excavated during removal of the USTs. After removal of the USTs was completed, the soil was placed back into the excavation because of strong hydrocarbon odors and the proximity to a school. Two laboratory-composited samples were collected from the stockpiled soil prior to placement into the excavation. TPH-g,BTEX and MTBE and TBA were all detected in the composite samples. 2.4. SOIL EXCAVATION PROCEDURES On 10 November 1998,approximately 250 yards ofhydrocarbon-impacted soil were excavated from the location of the former UST system. Soil was excavated using a backhoe with an approximate 15-foot reach capability. Excavated soil was field-screened for the presence of volatile organic compounds using an OVM. Soil was stockpiled on the eastern edge of the site. Approximately 150 yards of soil was loaded and transported to Forward Inc. Landfill under manifest for proper disposal on 10 November 1999. An additional 100 yards of impacted soil were transported to Forward Inc. Landfill for disposal on 14 December 1999. Soil samples collected from the floor and sidewalls of the excavation were obtained using abackhoe. A total of nine soil samples were collected from the floor and sidewalls of the over-excavation. TPH-g was detected at concentrations up to 80 milligram per kilogram(mg/kg) in the sample from ` the north wall, east end of the excavation. TPH-g was not detect in soil samples collected from the south,northwest,and east wall of the over excavation. Additionally,TPH-g was not detected in the samples collected from the south end of the west wall and from the floor of the excavation. BTEX compounds were detected at concentrations up to 1.0 mg/kg, benzene was only detected in the north west wall sample. MTBE and TBA were detected at concentrations up to 1.3-mg/kg and 8.9 mg/kg, respectively. MTBE was detected at the highest concentrations in the'northem portion of the over excavation,especially in the northern west wall sample,located at the northwest edge of the site under Monroe Avenue. Analytical results of soil samples are summarized in Tables 1 and 2. Advanced GeoEnvironmental,Inc.