ARCHIVED REPORTS_XR0005062 - Laserfiche WebLink

Home Browse Search

. 26 February 2003 AGE-NC Project No. 98-0520 ' . ;Page 3 of 4 ' Ethylbenzene was detected in samples MV-2, MW-3 and MW-5 at a maximum concentration of 140 ug/l, and xylenes was detected in well MW-5 at a concentrations of 120 pg/I. Benzene and toluene were not detected at or above l4boratory reporting limits in any of the ground water.samples. No other analytes were not detected at or-above laboratory reporting limits in-the ground water samples collected. Analytical results of ground water samples are summarized on Table 2. The laboratory report(CTEL Lab Project.No.CT214-0212083)and chain-of-custody forms are included in.Appendix C: 4.0, SUMMARY AND CONCLUSIONS ' Based upon data collected from the site AGE.concludes: • Depth to ground water at the site averaged approximately .20.54 feet btoc on ' 16 December 2002. The ground water level rose approximately 3.07 feet since the last . monitoring event. ; • On 16 December 2002 the ground water elevation at the site averaged approximately 16.04 feet above mean sea level; ground water flow was northwest at an average gradient of 0.002 ft/ft: ' TPH-g concentrations remained relatively stable in ground water samples collected from MW-1. through IV1W-7, MW-9. and MW-10, although a slight increase 'was observed compared with the previous quarterly monitoring'event..TPH-g was not detected in samples ' MW-4 and MW-9, and has not been detected in deep-screened well MW-6 since the well -was installed in December 2001. ' Ethylbenzene,and total xylenes were the only BTEX compounds detected,in two of the nine . ground water monitoring wells sampled;the concentrations were below the•DHS Maximum Contaminant Levels (MCLs) forVdrinking.water. ' • The•vertical-extent of impacted ground water has been defined. Impacted ground water does- not extend beyorid 45 feet bsg. ' The lateral extent of petroleum hydrocarbon-impacted ground water has not been defined northwest of the former USTs. 5.0. RECOMMENDATIONS ' Based upon data collected from the site, AGE recommends continued quarterly ground water •. monitoring. The next quarterly monitoring event is scheduled for March 2002. Advanced GeoEnvirohmental,Inc.