SITE INFORMATION AND CORRESPONDENCE

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Mr. Gregory Torlai, Jr - 2 - 3 April 2008 H & H Marina • Order No. 5-00-11938.The 18 January 2008 Quarterly Interim Remediation Report— Fourth Quarter 2007 (Report) reports that groundwater remediation is presently conducted by extracting groundwater from the 6-inch diameter extraction well EW-1, located about 50 feet east of the September 2007 spill source area, and treating it with a granular activated carbon (GAC) treatment system. During the fourth quarter, methyl tertiary butyl ether (MTBE) was detected at 41 micrograms per liter (Ng/L) in the treatment system influent. The effluent was non-detect for all constituents detectable by EPA laboratory analytical methods 8015M and 8260. Groundwater monitoring and reporting requirements for the site are set forth in Monitoring and Reporting Program (MRP) No. R5-2004-0828. Groundwater monitoring is conducted on a quarterly basis. Monitoring for the fourth quarter was conducted on 7 December 2007 and reported in the 21 January 2008 Quarterly Monitoring Report— Fourth Quarter 2007 (Fourth QMR). The highest concentrations of contaminants of concern (COC) were detected in monitoring wells MW-2, the well closest to the September 2007 spill, and MW-4, the well with the highest residual concentrations from the pre-1991 UST release. The three wells that typically exhibit the maximum COC concentrations are summarized in the table below and compared to monitoring results recorded before the September 2007 spill. Well Number MW-2 MW-3 I MW-4 MW-2 I MW-3 MW-4 Constituent June 2007 December 2007 AUDAL) TPHg 110 <50 3,200 220,000 200 2,600 TPHd <50 <50 <50 <50 <50 <50 Benzene <0.5 <0.5 <0.5 440 <0.5 <0.5 Toluene <0.5 <0.5 <0.5 26,000 10 19 Ethyl benzene <0.5 <0.5 7.6 7,900 6.4 5 Xylene <0.5 1 <0.5 1240 145,000 70 670 MTBE 13 1 <0.5 125 18.5 <0.5 1 100 TBA 5,300 500 1 <5 <0.5 <0.5 <5 Legend ug/L micrograms per liter < less than TPHg total petroleum hydrocarbons as gasoline TPHd total petroleum hydrocarbons as diesel MTBE Methyl tertiary butyl ether TBA Teritary butyl alcohol Our comments are presented below. 1. The Report states that the current interim groundwater remediation system can effectively exert hydraulic control on plume migration. The Site data do not support this conclusion for wells at the plume margins, including MW-4 and MW-14. During 2007, the Fourth QMR shows increasing TPHg concentration trends in MW-4 (except for the fourth quarter), and relatively stable MTBE concentration trends in MW-4 and MW-14. Treatment system data in the Report show influent concentrations of TPHg were non-detect (ND) for six of the nine