Laserfiche WebLink
' U-Haut#709-50 <br /> Additional Site Charactenzation BlaesEnvironntental <br /> 1 14 0%, respectivelyHigher g dissolved oxygen reading are typical in groundwater with lower levels of <br /> hydrocarbon impact <br /> ' 422 run wa er am le al ti al Results <br /> Results of laboratory analysis of the groundwater samples collected from the eight monitoring wells are <br /> summarized on Table 6 and discussed below The certified analytical report of groundwater sample <br /> analyses is included in Appendix G The extent of hydrocarbons in groundwater is illustrated <br /> Figure I0 on <br /> • The groundwater sample MW-6b, which is a duplicate of MW-6a, revealed results with an <br /> average of 83% of those reported for sample MW-6a These results are within the QA/QC <br /> ' limits followed by the laboratory <br /> • Analysis of the equipment blank sample indicated the presence of BTEX at concentrations <br /> ranging from 5 5 µg/L ethyl-benzene to 29 µg/L total xylenes The detection of hydrocarbons is <br /> likely due to the fact that the equipment blank sample was collected from the final wash rinse <br /> immediately after decontamination of purging equipment used at MW-6a Since the purging <br /> equipment used at MW-9a and MW-6a consisted of new disposable bailers, cross contamination <br /> was unlikely <br /> • Analytical results indicated therou <br /> g ndwater samples from monitor wells MW-1a, MW-3a, <br />' MW-4b, and MW-6a contained TPHg at concentrations greater than 1,000 µg/L Groundwater <br /> from MW-3a contained the highest concentrations of the sample suite with 160,000 µg/L TPHg <br />' and 18,000 µg/L benzene <br /> • Groundwater collected from MW-5a did not contain detectable concentrations of TPHg, <br /> benzene, or ethylbenzene Detectable concentrations of toluene and total xylenes were ere 0 5 µg/L <br /> and I I µg/L, respectively Despite these low detections, these results indicate the possible <br /> northern extent of the hydrocarbon plume <br /> • Groundwater collected from hydro-punch location HP-1 did not contain detectable <br /> concentrations of hydrocarbons This sample point indicate the probable southern extent of <br /> hydrocarbons in groundwater <br /> 18 <br />