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4 <br /> . suggest that the LPH hand bailing efforts appear to have been effective in removing LPH from <br /> MW-5 Monthly monitoring of the free product condition will be continued this quarter <br /> GROUNDWATER SAMPLE COLLECTION <br /> Groundwater samples were collected from each of the groundwater wells (TBI, MW3R, MW4, <br /> MW5, MW6, TB7, TB8 and TB 10), by EMC personnel on February 13, 1996 Prior to sample <br /> collection, at least three well volumes of groundwater were removed from each well using a <br /> portable submersible pump or bailer All equipment was cleaned using a solution of Alconox <br /> and water followed by two tap water rinses The actual groundwater samples were collected <br /> with disposable PVC bailers equipped with bottom emptying devices A new bailer was used <br /> for each sample collected Samples were transferred into the laboratory supplied 40 ml VOA <br /> vials pending analyses The chain-of-custody documentation is presented in Appendix B <br /> ANALYTICAL DATA <br /> Each groundwater sample was transported on ice in a light-proof chest to American Analytics <br /> The samples were analyzed for total hydrocarbons (TPHg) and volatile aromatic compounds <br /> (BTEX) by EPA methods 8015 and 8020, respectively Table 1 presents a summary of the <br /> TPHg and BTEX data The complete laboratory reports for the current samples are included <br /> in Appendix B <br /> The current results indicate the presence of TPHg in 7 of the 8 wells sampled (ranging from <br /> 0 13 mg/L to 20 mg/L) Benzene concentrations ranged from less than detectable to 3,200 ug/L <br /> with the highest concentrations noted in well MW5 An interpretation of the dissolved <br /> hydrocarbon plume is shown on Figure 2 <br /> CLOSING <br /> Based on the recent site investigation and monitoring program, it appears that the groundwater <br /> beneath the site is impacted with high concentrations of dissolved phase hydrocarbons Although <br /> the groundwater elevation has fluctuated, the historical monitoring events suggest that the flow <br /> direction of groundwater across the site is generally to the north-northeast and east Thrifty will <br /> continue to monitor the on-site wells on a quarterly basis <br /> If you have any questions, please contact Mr Ray Freidnchsen at (310) 923-9876 <br /> Very truly yours, <br /> Peter�D'Arnic <br /> Manager Environmental Affairs <br /> cc CVRWQCB, Elizabeth Thayer <br />