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r I FREE PRODUCT REMOVAL Since July 1995, no liquid phase hydrocarbon (LPH) was present on the water cable 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 COLLECTION Groundwater samples were collected from each of the groundwater wells (MW4, MW-5, MW6, TBI, TB7, TBS, and TB 10) by EMC personnel on November 13, 1995 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 gi oundwatei samples were collected with disposable PVC bailers equipped with bottom emptying devices A nem 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 hydrocai bons (TPFIg) and ,,olatile aromatic compounds (BTEX) by EPA methods 8015 and 8020, respectively T�ible i presents a summary of the TPHg and BTEX data The complete laboratory repoi is for the current samples ai e included in Appendix B The current results indicate the presence of TPHg in each of the sampled wells (ranging from 2 5 mg/L to 92 mg/L) Benzene concentrations ranged from 6 4 ug/L to 19,000 ug/L with the highest concentrations noted in well T13-7 An interpi etation of the dissolved hydrocai bon plume was not established this quarter as all site wells exhibited detectable concentrations However, benzene concentrations are plotted on 1Figui e 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 dissol,,ed phase hydrocarbons Although the groundwater elevation has fluctuated, the histoi ical monitor Ing 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, while in the process of installing a remediation system