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• Groundwater samples were col�cted from the on-site wells by EMC personnel Prior to sample collection, at least three well volumes of groundwater were removed from each well by a Portable submersible pump or bailer During the purging of groundwater, pH,v6o�nductivity, temperature and turbidity were monitored at selected intervals This data is included in Appendix A along with the gauging data for the reporting period All equipment was cleaned using a solution of Alconox and water followed by two tap /water rinses The actual groundwater samples were collected with a teflonbailer equipped with a bottom emptying device before being transferred into the laboratory supplied 40 ml VOA vials pending analyses The chain-of-custody documentation is presented in Appendix B ANALYTICAL DATA Each groundwater sample was transported on ice in a light-proof chest to Smith-Emery Laboratory The samples were analyzedfp r total hydrocarbons (TPHg) and volatile aromatic compounds (BTEX) by EPA methods 8015 and 802( , respectively Table 1 presents a summary of the TPHg and BTEX data The complete laboratory reports for the current samples are included in Appendix B The results indicate the presence of TPHg in three of the six wells on-site TPHg concentrations of 2,500 ug/L and 570 ug/L were noted in groundwater from wells MW2 and MW3, respectively Wells MW4 and MW8 had less than detectable levels of dissolved hydrocarbon Well MW7 was_qg at the time of sampling and therefore no sample was obtained from this well A benzene iso-con map is presented on Figure 2 CLOSING Based on the site investigation and monitoring program, it appears that the shallow water zone found beneath the site exhibits the presence of dissolved hydrocarbons The monitoring events accomplished to date suggest the flow direction of groundwater across the site is generally to the east-southeast Thrifty will continue to monitor the on-site wells on a quarterly basis If you have any questions, please contact Karl Kerner at (310) 923-9876 Very truly yours, C_C{ Peter D'Amico Manager Environmental Affairs cc CVRWQCB, Elizabeth Thayer