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ski it EXHIBIT R. Analysis of the water sample from monitor well MW1, the westerly well on the site, was reported non-detect for all of the analyzed contaminates, as was the water sample from monitor well MW3, the easterly well, located in the sidewalk adjacent to the EE property. The water sample from monitor well MW2, the northerly well on the site, was contaminated. Laboratory analysis reported the water to have contamination concentrations t of 96.8 ppm TPH-Gas, 400 ppb Benzene, 400 ppb Ethyl Benzene, 300 ppb Toluene, and t 2000 ppb Xylene. All the water samples were analyzed for Lead using EPA Method 200.9 f� and the laboratory reported them as non-detect. Y CONCLUSIONS k Laboratory results of the soil and water samples obtained from the recent construction of the three (3) monitoring wells, two (2) located on the site and one (1) located in the sidewalk adjacent to the east side of the building, confirmed that soil and groundwater E contamination exists under a portion of this site. E When the 500 gallon UST was removed from the property on February 11, 1988, the soil sample taken from the bottom of the excavation at a depth of 13 feet was contaminated f with 150 ppm Tolune, 370 ppm Xylene, and 1000 ppm, TPH-Gas. The excavation has . g remained open since the date of the tank removal. Monitor well MW1, located ten and one-half (10 6") feet away from the west side of the excavation reported no soil or groundwater contamination. Monitor well MW3, located approximately fifteen (15 ) feet i southeast from the southeast corner of the excavation and constructed in the sidewalk, also { J reported no contamination of the soil or groundwater. Monitor well MW2, is located approximately twelve and one-half (1212 ) feet north of the northeast corner of the excavation. Soil contamination of petroleum hydrocarbons were found in the soil starting at a depth of +/- 101/z and continuing down -to the top of the water table which was . encountered at twenty (20 ) feet below ground level. The water sample from this monitor well also reported significant amounts of contamination. Monitor well MW2, is situated in a down radient position from the tank excavation and the other two monitoring wells. The g regional water gradient is to the east and northeast. The water gradient, at this site, i derived from the measurement taken in these monitoring wells on March 8, 1994, show the E� gradient to be in a northeast direction. It is therefore possible that the soil contamination originally found at the base of the excavation could have been flushed clean by surface run- off entering the excavation and peculated down into the water and then migrated down i gradient toward monitor well MW2. Based upon the laboratory results, it does not appear that the shallow water table 1 ` underlying the building and tank pit area is presently contaminated with petroleum (gasoline) hydrocarbons. This latest work has found contamination on the northeast side of the site, but the extent of the soils and groundwater contamination on site has not been t delineated. RECOMMENDATIONS It is recommended that a monthly groundwater monitoring program be initiated for this site , for a period of 3 consecutive months to record the changes in groundwater elevations 7