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1 <br />' 30 December 2002 <br /> AGE-NC Project No 02-0950 <br />' Page 6 of 7 <br />' 5.0. SUMMARY AND CONCLUSIONS <br /> Based on the data collected from the site, AGE finds <br />' • Clay and silt occurred under most of the site, with the exception of an apparently laterally <br /> continuous coarse sand unit at between 25 feet and 30 feet bsg and thin, laterally <br />' discontinuous sand layers at approximately 10 feet and 25 feet bsg at location B2 <br /> • Ground water occurred at approximately 22 feet bsg during the October 2002 boring event <br />' • Petroleum hydrocarbons were detected in the soil samples analyzed from boring B1, <br /> advanced within the former UST excavation, and B2 and B3 located east and southwest, <br /> respectively, of the former UST The highest concentrations of TPH-g, TPH-d and BTEX <br />' compounds were detected at 15 feet bsg in boring B2 <br /> • With the exception of TPH-d in B3, total petroleum hydrocarbons concentrations were <br /> significantly over 1000 µg/1 in ground water samples collected from each boring <br />' • BTEX compounds, 1,2-DCA and EDB present in the ground water samples all exceeded the <br /> DHS's Maximum Contaminant Levels for drinking water <br />' • • The lateral and vertical extent of petroleum hydrocarbons-impacted soil and ground water <br /> have not been delineated <br /> 6.0. RECOMMENDATION <br />' Based on the findings of the environmental activities recounted in this report, AGE recommends <br /> g p <br />' • Preparation of a work plan for installation of monitoring wells and additional soil borings <br /> to assess the lateral and vertical extent of petroleum hydrocarbon-impacted soil and ground <br /> water at the site <br />' • Conduct a sensitive receptor survey to locate potential vertical conduits including municipal, <br /> domestic,irrigation and ground water monitoring wells within a 2,000 foot radius of the site, <br />' and to locate any on-site or nearby septic systems that could potentially serve as a pathway <br /> to surface ground water <br /> 7.0. LIMITATIONS <br />' Our professional services were performed using that degree of care and skill ordinarily exercised by <br /> • environmental consultants practicing in this or similar localities The findings were based upon <br /> analytical results provided by an independent laboratory Evaluation of the geologic/hydrologic <br /> Advanced GeoEnviron mental,Inc <br />