Laserfiche WebLink
' a, 07 May 2004 <br /> i AGE-NC Protect No 98-0534 <br />' Page 13 of 14 <br /> northwest flow direction The flow direction at the site has heed-ranged from north-northwest E p, <br />' to south-southwest during this investigation ) <br /> U <br /> • Concentrations of petroleum hydrocarbons have decreased in MW-1 through MW-8.to 5� <br /> -r, <br /> non-detectable concentrations between the August 2000 and February 2004 ground water <br /> monitoring events, initial elevated petroleum hydrocarbon concentrations in ground water <br /> encountered during tank removal and soil boring activities were not detected in quarterly , <br /> ground water monitoring samples The lack of high concentrations during quarterly <br /> monitoring indicates the initial elevated concentrations were due to minor releases of <br /> petroleum hydrocarbons as a result of contractor error,product spillage,during tank removal <br /> Field notes from the geologist on site during removal activities indicate product spilling from <br /> UST during removal The dissolved hydrocarbon plume appears'to be well-defined,low in <br />' concentration`and stable Table 2 summarizes analytical results for all ground water samples <br /> collected at the site <br /> • A volume-mass calculation of the remaining petroleum hydrocarbon impacted soil at the site _ <br />' yields an approximate volume of 341 cubic yards Mass-volume calculations indicate that <br /> an estimated 2 3 gallons of adsorbed petroleum remain in soil _ �a <br /> a Based on depth to ground water measurements observed at the site from August 2000 to <br />' February 2004, any remaining residual TPH-impacted soil at the site is at or above the <br /> maximum ground water elevations recorded during the monitored period fe <br /> 5ul`` <br />' 9 AGE concludes that petroleum hydrocarbons remaining beneath the site appear to pose <br /> minimal risk to human health and beneficial use of ground water down-gradient or near the <br /> subject site <br /> 7.0. RECOMMENDATIONS <br /> 1 <br /> Based upon data collected from the site, AGE recommends the following <br /> • No further subsurface investigation at this time <br /> • Consideration of the facility for closure as a low risk ground water site <br /> • Destruction of wells in accordance with applicable regulations as part of the site closure <br /> preparations <br /> Advanced GeoEnvironmental,Inc <br /> I F <br />