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In December 1994 and again in February 1995 groundwater samples were collected from MW1. No analytes were detected in these samples. Historical analytical results for groundwater samples are presented in the reports included in Attachment A. REMEDIATION Soil In January 1991 five soil samples were collected from the UST pit during the UST removal. TPHg and BTEX were detected in all five samples. In March 1991 source removal excavation was conducted in the UST pit. Fourteen verification soil samples were collected, and the excavation was backfilled. The samples were analyzed for TPHg, TPHd, BTEX. Several samples were reported to contain elevated concentrations of analytes, which indicated that contamination remained near the middle of the former 10,000 gallon UST and beneath the center of the former 500 gallon UST. In May 1993, following selective removal of previously placed backfill, residual petroleum hydrocarbon • contaminated soil was excavated from the remaining areas of identified impact. Soil was excavated near the center of the 500 gallon UST, beginning at a depth of approximately 16 ft below groundsurface, and near the southwest corner of the UST pit and near the former dispenser location at a depth of approximately 22 ft below groundsurface. The excavation was continued until all physical evidence of contamination was absent. Approximately 150 cubic yards of contaminated soil was removed during this action. Following the completion of excavation, seven verification soil samples were collected and submitted to a laboratory for analysis of TPHg and BTEX. The laboratory was also directed to analyze any sample for TPHd that eluted late peaks on the chromatogram during analysis, which would be an indication of longer chain hydrocarbons. The analytical results did not indicate the presence of TPHg or BTEX in any of the soil samples. Additionally, the chromatogram did not indicated the presence of longer chain hydrocarbons (TPHd). Details of excavation activities are found in the June 3, 1993 report included in Attachment A. Groundwater _ Remedial action for groundwater has not been implemented due to the source removal during excavation activities, and the continued absence of TPHg and BTEX in groundwater. 4