ARCHIVED REPORTS XR0005781 - Laserfiche WebLink

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SOIL/WATER PROBES Prior investigative work had defined the limits of contamination to the south and southeast of the site of the removed UST' s, and had stablished a general north/northeast gradient However, the plume had not een Ynea e north and west , and the available data indicated that the contamination had migrated off th The seven (7) s al owprobes placed in October, 1995 , were designed to locate those limits Laboratory analyses of soil samples from the se en probe holes revealed that only ethylbenzene, xylene, & TPH were measured from the soil sample taken at 16 ' in Probe #3 (P-3 , ) all others were below detection limits Refer to EXHIBIT D for a copy of those results . Minor amounts of ethylbenzene, toluene, xylene & TPHg were measured from the soil sample at 16 ' in monitoring well #1 . Monitoring well #3 recorded low levels of BTEX & TPHg from the soil sample at 161 , & benzene, ethylbenzene, & toluene from a soil sample at 23 ' All other soil samples were below detection limits . A summary of those results are included as TABLE II & IIS Based upon that data, "zero" lines for soil contamination can be inferred as shown on PLATE VTI The contamination measured at 16 ' in P-3 appears anomalous when compared to the other data, the reason for this cannot be explained based on the, available data Analyses of water samples from the seven probes (EXHIBIT D, ) revealed that only SP-2 & SP-3 were above detectiion limits SP-2 measured benzene at 3 4 ug/L, toluene at 1 .3 ug/L, ethylbenzene at 1 6 ug/L, xylenes at 2 5 ug/L, and TPHg at 187 ug/L Levels detected in SP-3 were ethylbenzene at 5 6 ug/L, xylenes at 10 3 ug/L, and TPHg at 326 ug/L PLATES II through VI show estimated lines of equal concentration of BTEX & TPHg based on the 10/25/95 data from the soil probes, and the 12/8/1995 data from the moni- toring wells Contours on ethylbenzene xylene & TPHg indicate that the levels measured in P-3 appear anomalous t is possible that anv er source axis s i area of P-3 , but a thorough title search of the area did not reveal evidence of any other UST' s MONITORING WELLS - The results of the laboratory analyses of the latest water samples from the five (5) monitoring wets, (TABLE I, ) continue to show MW-1 with the highest levels of contam- inants, with MW-3 second MW-2 , which was clean when sampled in August, measured benzene, toluene, ethylbenzene, & TPHg in December The amounts measured may not be representative, since the bailer blank was contaminated, which probably skewed the results 6