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enviros® Ground water samples were collected from on-site monitoring wells on a quarterly basis from 1990 through 1996 Based on ground water analytical data collected to date, it does not appear that ground water has been significantly impacted by petroleum hydrocarbons TPH-G and benzene have not been detected in Wells MW-1, MW-2 or MW-3 since August 1993 Trace concentrations of benzene have been detected in Well MW-4 on only two occasions since August 1993 Most recently, all ground water monitoring wells have shown ND concentrations of petroleum hydrocarbons Hydrocarbons in ground water have only been detected occasionally and are not indicative of a continuous hydrocarbon plume in the ground water The extent of impacted ground water has been delineated and is limited to the vicinity of the former underground storage tank There is no indication of off-site migration Conclusions Investigations conducted to date indicate that hydrocarbon impacted soils are defined and are limited in extent to the vicinity of the former UST pit Ground water sampling data indicate trace to ND concentrations of TPH-G and BTEX are occasionally present in the ground water in the vicinity of the former underground tank pit Based on six years of ground water sampling data collected to date, there does not appear to be an established ground water plume present Recommendations Data presented in this document indicate that petroleum hydrocarbons detected at this site in soil and ground water are delineated and limited in extent Six years of continuous • quarterly ground water sampling indicate that petroleum hydrocarbon concentrations in the ground water are detected only occasionally and are not indicative of an adverse hydrocarbon ground water plume condition Based on these conclusions, there does not appear to be a significant threat to water quality at this site Therefore, we respectfully request that case closure be granted 96373 3