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FREE PRODUCT REMOVAL In September 1993, liquid phase hydrocarbons (LPH) appeared as only a sheen on the water table in MW-5 In 1993, the thickness of the LPH in this well ranged from 0 4 to 1 78 feet These data suggest that the LPH removal efforts appear to have been effective in removing LPH from MW-5 During the next quarter, Thrifty will monitor the LPH on a monthly basis If LPH levels increase, Thrifty will begin a regiment of weekly monitoring/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 using 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 rinses The actual groundwater samples were collected with disposable PVC bailers equipped with bottom emptying devices A new bailer was used for each sample collected Samples were transferred into the laboratory supplied 40ml 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 . Laboratories The samples were analyzed for total hydrocarbons (TPHg) and volatile aromatic compounds (BTEX) by EPA methods 8015 and 8020, respectively Table I 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 12 mg/L to 150 mg/L) Benzene concentrations ranged from 1,700 ug/L to 16,000 ug/L with the highest concentrations noted in well MW-6 An interpretation of the dissolved hydrocarbon plume was not established this quarter as all site wells exhibited detectable concentrations However, benzene concentrations are plotted on Figure 2 for reference CLOSING Based on the recent site investigation and monitoring program, it appears that the groundwater beneath the site exhibits the presence of dissolved phase and intermittent liquid phase hydrocarbons The monitoring events accomplished to date suggest the flow direction of groundwater across the site is generally to the north-northeast and east Thrifty will continue to monitor the on-site wells on a quarterly basis