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following strict Chain-of-Custody procedures to a.state certified laboratory and analyzed for volatile aromatic compounds of benzene,toluene, ethylbenzene, and xylenes by EPA method 8020 for total petroleum hydrocarbons (TPH-g) by EPA method 8015 modified for gasoline, and for oxygenates by EPA method 8260. A summary of historic analytical sampling results are provided in Table 1, and copies of the laboratory analytical reports for this reporting period are included in Appendix B. The highest dissolved TPH-g, benzene, and MTBE concentrations recorded during the Second Quarter 1999,were 230,000 micrograms per liter(ug/L), 38,000 ug/L, and 7,100 ug/L respectively, from monitoring well VW-2B (this vapor monitoring well was mislabeled.on the Chain-of-Custody as MW-12, and was relabled as VW-2B by American Analtyics as requested by EMC). TPH-g, benzene,and MTBE distributions in groundwater are presented as isoconcentration maps in Figures 3, 4 and 5, respectively. Monitoring well MW-12 was installed on March 31, 1999 and has four feet of screen from approximately 73 to 69 feet bgs. The well log and analysis will be forwarded to your office in the finalized report prepared by our consultant, The Park Corporation. Since the third quarter of 1997,Thrifty has analysed for the requested oxygenates: di-isopropyl ether, ethanol,ethyl-tert butyl ethyl,methanol, tert-amyl methyl ether,tert-butanol, and methyl tert-butyl ether(MTBE) by method 8260. Results above detection limits were detected in monitoring wells MW-ll for tert-butanol at 0.92 mg/L, and MW-12 for tert-butanol at 3.8 mg/L, and 15 mglL methanol. Analytical results are included in Appendix A. Summary and Recommendations On March 31 and April 1, 1999 Thrifty retained the services of The Park Corporation to complete the tasks outlined in the approved work plan dated March 1, 1999. A groundwater aquifer pump test was conducted, and groundwater monitoring well (MW-12) was installed to 73 feet below surface grade to vertically assess the extent of hydrocarbon constituents beneath the site. Monitoring well MW-7 was resurged and bailed to create a groundwater flow into this well. Park also repaired the surface inside the monitoring well boxes, and bolted down the monitoring well covers. On July 15, 1999, The Park Corporation delivered the draft report entitled "Additional Site Assessment and Remediation SvstemDes j n" (including a site pump test) for Thrifty to review. Once Thrifty reviews this report, it will be returned to The Park Corporation to finalize. A copy of the final report will be forwarded to your office for review and comment. Thrifty plans to have the site resurveyed to an official benchmark before next quarter,and a new site map will be generated. Thrifty plans to continue quarterly groundwater monitoring and sampling of all monitoring and