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' F , 5 4 ' 12 May 1995 AGE-NC-95-0121 Page 4 of 4 ' diesel analysis of samples from MW-1 to MW-5 were not consistant with typical diesel standards ' s , ' Benzene, toluene, ethylbenzene and xylenes were detected in samples from MW-1 through MW-4, MW-6 and MW-7 at concentrations from 20 ppb to 1,100 ppb The analytical results are summarized in Table 2 The laboratory report and chain-of-custody are included in Appendix B 5.0. CONCLUSIONS'& RECOMMENDATIONS The 'rise of over 6 feet of the water table observed between December 1994 and May 1995 is attnbuted`to the above average precipitation in the region Typically, a rise of water table would ' result in an increase of hydrocarbons in water samples during a monitoring event Except for MW-5 and MW-9, a decrease of hydrocarbons was detected in the samples A reduction trend of hydrocarbon concentrations over the last three years was noted in the majority of monitoring samples ' over the last three years Since remediation activities were not conducted at the site, the decreasing trend of hydrocarbon concentrations suggest the presence of a fairly active natural degradation process Additional ground water monitoring wells will be required at the site to define the limits of the ' dissolved hydrocarbons plume In a letter dated 10 April 1995, the PHS-EHD has also stated that "feasibility studies to deternime the most efficient, cost effective remedial approach must be conducted at the site " We recommend installation of at least two additional monitoring wells as well as installation of a remediation well for conducting a vapor extraction test and, of necessary, a ground water pump test After the new wells have been installed, all monitoring wells at the site should be sampled Upon completion of the sampling and feasibility testing, a Corrective Action Plan (CAP) should then be prepared ` 5 5.0. LIMITATIONS Our professional services were performed using that degree of care and skill ordinarily exercised by environmental consultants practicing in this or similar localities The findings were based upon analytical results provided by an independent laboratory Evaluations of the geologic/hydrogeologic conditions at the site for the purpose of thus investigation are made from a limited number of available data points(i a monitoring wells) and subsurface conditions may vary away from these data,points No other warranty, expressed,or implied, is made as to the professional recommendations contained in this report FS