ARCHIVED REPORTS_XR0012253 - Laserfiche WebLink

Home Browse Search

' 22 July 2003 AGE-NC Project No 00-0764 ' Page 3 of 4 3 2 LABORATORY RESULTS OF GROUND WATER SAMPLES ' at the site on 25 April 2003 are The results of laboratory analysis of ground water samples collectedp ' as follows • TPH-g was detected in the samples from ground water monitoring well MW-3 at a concentration of 310 micrograms per liter(µg/1) • Benzene was detected in the samples from monitoring well MW-3 at a concentration of 16 µg/l benzene ' • 1,2-DCA was detected in the samples collected from well MW-4 at a concentration of 5 4 µg/1 1,l-DCA was detected ��at e samples collected from wells'•and MW-4 at a concentration of 11 µg/1 anell � i • In addition, isopropylbenzene was detected in sample MW-3 at 3 0 gg/1 !I'ah ' No additional target analytes were detected in the samples analyzed Laboratory results of samples analyzed for petroleum hydrocarbons are summarized in Table 2 and Table 3 The laboratory reports (CTEL Laboratory ID CT214-0304158),quality assurance and quality control(QA/QC)reports and chain-of-custody form is included in Appendix C ' 4.0. SUMMARY AND CONCLUSIONS Based upon the results of this quarterly monitoring event, AGE concludes • Ground water flow direction was inferred to be towards the east from the former UST location, at a gradient of approximately 0 005 ft/ft ' • The highest concentrations of dissolved petroleum hydrocarbons were detected in the sample collected from well MW-3, near the former UST location • The benzene concentration in well MW-3 and the 1,1-DCA concentration in.well MW-4 are above the DHS's Maximum Contaminant Level of 1 0 µg11 and 5 0 µg/1, respectively, in drinking water ' • At the present time, the vertical extent of the dissolved hydrocarbons have been defined by borings B 1 and well MW-5 The lateral extent of the dissolved hydrocarbons have been ' defined by shallow wells 5.0. RECOMMENDATIONS 1 Based on the results of this investigation, AGE recommends Advanced GeoEnvironrnentai,Inc.