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Ms Mary Meays Page 3 <br /> March 3, 1997 <br /> ANALYTICAL RESULTS <br /> Samples from all ten wells were analyzed for TPH(g) and TPH(d) by USEPA <br /> Method 8015 modified and for BTEX compounds using USEPA method 8260 <br /> Samples from all ten wells were also analyzed for a suite of ground water quality <br /> parameters that will be used as a baseline point of comparison to evaluate the <br /> effectiveness of the ORC process Four samples were also collected for <br /> heterotropic plate counts from MW-4, MW-5, MW-1A, and MW-2A The water <br /> quality and plate count results were primarily intended as a baseline, they will <br /> not be included in the ongoing monitoring program every quarter <br /> All analyses were performed by Inchcape Testing Services of San Jose, California, <br /> Iwith the exception of the plate counts that were sent to Inchcape Testing Services <br /> of Colchester, Vermont Laboratory data sheets and Chain-of-Custody forms <br /> associated with the October 1996 sampling event are included in Attachment B of <br /> this letter <br /> TPH as diesel and gasoline and BTEX compounds were detected in ground water <br /> samples collected from Former Tank Sites #1 and #2 at concentrations similar to <br /> those associated with recent sampling rounds These detections are summarized <br /> below and in Tables 1 and 2, respectively <br /> Baseline water quality parameters are presented in Tables 3 and 4 for the former <br /> tank sites 1 and 2, respectively If the ORC process has the intended result, over <br /> time many of these parameters will change <br /> Former Tank Site #1 <br /> As presented in Table 1, as in previous sampling rounds, TPH(g) was detected at <br /> only two sites (MW-4, 0 090 mg/1 and MW-5, 2 0 mg/1) Diesel was detected in <br />' all of the wells Detected concentrations were low and ranged from 0 046 mg/1 <br /> (MW-3) to 0 083 mg/l (MW-1) These wells (other than MW-3 and MW-5) were <br />' not previously analyzed for TPH(d) As in previous sampling events, BTEX <br /> compounds were only detected in the samples collected from MW-4 and MW-5 <br /> The MW-5 BTEX detections were consistent with previous sampling events The <br /> MW-4 BTEX detections were slightly higher then those measured in recent <br /> events <br />' As noted above, the water quality results presented in Table 4 are considered <br /> baseline, and will be compared to future monitoring results to evaluate the <br /> effectiveness of the ORC process The heterotropic plate counts were analyzed as <br />' an indicator of how active the microbes are in ground water under current (pre- <br /> ORC) conditions Based on the analytical results, in wells MW-4 and MW-5 (the <br /> • two wells for which plate counts were conducted), microbial organisms are <br /> present at detectable levels <br />