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FREE PRODUCT REMOVAL In June 1993, liquid phase hydrocarbons(LPH) appeared on the water table in MW-5. In 1993, the thickness of the LPH ranged from 0 4 to 1.78 feet. EMC removed a total of 3 15 gallons LPH through weekly hand bailing efforts. To April, 1994, the thickness of LPH has ranged from a sheen to 0.02 feet. Currently, no visible LPH is noted on the water table in MW-5. Therefore, the LPH removal efforts appear to be effective removing LPH in MW-5. During the next quarter, Thnfty will monitor the LPH on a monthly basis If LPH levels increase, Thrifty will begin a regiment of weekly monitonng/bailing. GROUNDWATER_SAMPLE COLLECTION Groundwater samples were collected 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, conductivity, 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 ruses. The actual groundwater samples were collected with disposable PVC bailers equipped with bottom emptying f devices A new bailer was used for each sample collected Samples were transferred into the laboratory supplied 40m1 VOA vials pending analyses. The chain-of-custody documentation is presented in Appendix B. �1 ANALYTICAL DATA Each groundwater sample was transported on ice in a light proof chest to American Analytics Laboratory or Smith-Emery Laboratories The samples were analyzed for total hydrocarbons ('IPHg)and volatile aromatic compounds (BTEX) by EPA methods 8015 and 8020, 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 current results indicate the presence of TPHg in all wells on site (ranging from 0 15 mg/L to 36 mg/L) Benzene concentrations ranged from 6.5 ug/L to 1,000 ug/L with the highest concentrations noted in wells MW-3R and MW-4. An interpretation of the dissolved hydrocarbon plume was not established this quarter as all site well exhibited detectable concentrations However, benzene concentrations are plotted on Figure 2 for reference. A