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. FREE PRODUCY REMOVAL In July 1995, no liquid phase hydrocarbon (LPH) was present on the water table in well 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 hand bailing efforts appear to have been effective in removing LPH from MW-5 Monthly monitoring of the free product condition will be continued this quarter GROUNDWATER SAMPLE CQLLECTION Groundwater samples were collected from wells MW4, MW6, TB7, and TBS by EMC personnel on August 16, 1995 (Note samples from wells TB7 and TB8 are identified in the lab reports as "J" and "D", respectively ) 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 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 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 each of the sampled wells (ranging from 1.1 mg/L to 110 mg/L). Benzene concentrations ranged from 1,100 ug/L to 18,000 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 is impacted with high concentrations of dissolved phase hydrocarbons Although the groundwater elevation has fluctuated, the historical monitoring events suggest that 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.