ARCHIVED REPORTS XR0006465 - Laserfiche WebLink

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3.2 SITE CONDITIONS A. GROUND WATER: The latest chemical results (sampled 11/27/90 ) indicate that dissolved benzene in monitor wells MW-2, MW-3 , MW-4, MW-6 , MW-8 , MW-9 and MW-10 substantially exceeds the action level for drinking water of 1 .0 ppb, set by the DHS, see Figures 5A and 5B. Monitor well MW-7 contains a lower benzene value of 8 .5 ppb and monitor well MW5 is below the detection limit (<0 .3) for benzene. Monitor well MW1 contained 0.081 of floating product. EDB concentrations were below reporting limits for all wells sampled on 5/4/89 (MW-1 , MW-2, MW-4, MW-5, MW-6, MW-7 , MW-8 , and MW-9 ) so this analysis was not carried on. Complete water results are presented in TABLE 1 of this report. Strong to moderate bio-odors were also noted along with a grey green coloration of the purged ground water from monitor wells MW3 , MW7, MW8, and MW10. Monitor wells MW4 , MW5, MW7 and MWS were also analyzed for fecal coliform. These samples were placed into 500 ml plastic containers and hand delivered that day to Eureka Laboratories . Eureka used the Colilert method for Total Coliform and Fecal Analysis. All wells tested positive at the following results : WELL RESULTS MPN/100 ml MW4 >16 MW7 >16 MW5 >16 - t MW8 >2400 The above results indicate that the ground water at and near monitor well MW8 along the eastern edge of Pacific Blvd. , is contaminated with fecal coliform. B. SOIL: As has been shown in the "Update Status Report, February 23 , 1990" soil contaminated with gasoline range hydrocarbons exists beneath the underground storage tank excavation from the 25 foot depth to top of ground water and at the 40 foot depth to top of ground water around monitor well MW10 . The capillary fringe area (50 foot depth) shows the spread of contaminant out to monitor wells MW1, MW2 and MW3, see Table 2 and Figures 6A and 6B. 5