ARCHIVED REPORTS_XR0006029 - Laserfiche WebLink

Home Browse Search

I n ' 31 August 2004 ! AGE-NC Project No 95-0173 ' Page 4 of 10 ' elevations were calculated to be between 19 73 feet(MW-8)and 20 89 feet(MW-5)below mean sea level Generally, ground water elevation at the site Increased an average 2 65 feet between the November 2003 and the March 2004 ground water monitoring events The March 2004 ground water flow direction at the site was inferred to be east at the former UST release to northeast south of the site, at an approximate gradient of 0 003 ft/ft(Figure 3),GeoTracker ' confirmation pages of the submitted ground water monitoring electronic deliverable format(EDF) files are Included in Appendix G ' 2 4 2 LABORATORY RESULTS OF GROUND WATER SAMPLES 19 MARCH 2004 ' A total of nineteen ground water samples were submitted to CAL for analysis TPH-g was detected from ten ground water samples collected from wells MW-1,MW-2,MW-4,MW-6,MW-13 (A-C), AW-1 (A and B) and AW-213 at concentrations as high as 13,000 micrograms per liter(µg/1) in the sample from AW-1B Various BTEX constituents were detected from 9 ground water samples collected from wells MW-2, 10) MW-4,MW-13 (A-C),AW-1 (A and B)and AW-2(A and B)at concentrations as high as 2,600µg11 (xylene, AW-IA) The maximum benzene concentration was detected from sample AW-IA at a ' concentration of 640 µg/I 1,2-DCA was detected in four water samples collected from wells MW-3, MW-4, MW-9 and ' AW-113 at concentrations as high as 4 6 µg/l from MW-113, MTBE was detected from the water sample collected at well MW-4 at a concentration of 0 52 µg/l No other fuel components were detected in the samples analyzed Previous and current analytical results of groundwater monitoring ' well samples are summarized in Tables 3 and 4,respectively The laboratory report(CAL Reference No 6789)and chain-of-custody forms are presented in Appendix C,GeoTracker confirmation pages of the submitted laboratory electronic deliverable format (EDF) files are included in Appendix G 2 4 3 LABORATORY RESULTS OF GROUND WATER RE-SAMPLE 09 APRIL 2004 Due to discrepancies in the ground water monitoring data collected at well MW-13C, the well was re-sampled on 09 April 2004 and submitted to CAL for analysis of TPH-g, BTEX and MTBE TPH-g was detected at a concentration of 140 µg11, BTEX constituents were detected at concentrations of I l µg/l benzene, 29 µg/1 toluene, 5 4 µg/l ethylbenzene and 16 µg/l xylene (Table 3) ' Advanced GeoEnvironmental,Inc 1