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