SITE INFORMATION AND CORRESPONDENCE

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r Mr. Gregory Torlai, Jr. • -2 - • 3 August 2009 H&H Marina According to the First IRR, between 12 December 2008 and 30 March 2009, it is estimated that the treatment system operated at about 0.56 gallons per minute and removed about 0.235 pounds of MTBE from groundwater. During the first quarter of 2009, maximum concentrations of TPHg, MTBE, and TBA in influent groundwater samples were 2,100 micrograms per liter (Ng/L), 1,700 pg/L, and <5 pg/L, respectively. The effluent was non-detect (ND) for all constituents detectable by EPA 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 quarterly. Monitoring for the first quarter 2009 was conducted on 30 March 2009. The First QMR shows that the highest concentrations of TPHg, MTBE, and TBA were in monitoring well MW-4 at 1,800 Ng/L, 90 pg/L, and 930 pg/L, respectively. Between September 2007 and February 2008 the highest concentrations of COCs were generally detected in MW-2, the well that was degraded by the gasoline AGT release. The first quarter 2009 results represent the first time that COC concentrations in MW-2 have been lower than those observed in MW-4 since September 2007. The TPHg and MTBE concentrations are one to three orders of magnitude less than the previous quarter. BTEX and the lead scavenger 1,2-dichloroethane (1,2-DCA) were ND in MW-2. To address the low mass removal rates currently being achieved by the IRM system, H & H recommends (1) retrofitting MW-2 as an additional extraction point, (2) upgrading the IRM system power supply, and (3) installing three additional groundwater extraction wells. H & H Marina's 13 February 2009 Additional Site Assessment Report— December 2008 — January 2009 (Assessment Report) recommended revisions to the monitoring requirements of MRP No. R5-2004-0828. Central Valley Water Board staff sent a draft MRP on 16 April 2009 and requested H & H's comments on it by 29 May 2009. H & H's comments request that the revised MRP (1) require monitoring for 1,2-DCA, (2) reduce all quarterly monitoring to semi-annual in accordance with the State Water Resources Water Board's (State Water Board) 19 May 2009 Resolution 2009- 0042, (3) suspend sampling for TPHg and benzene, toluene, ethylbenzene and xylenes (collectively BTEX) in MW-8, MW-10, MW-11, MW-12 and MW-14 based on footnote 5 of the draft MRP, (4) suspend all sampling in MW-8, MW-10, MW-11 and MW-12, (5) sample EW-1 only when the treatment system is in operation, and (6) remove surface water sampling points IDCE and IDCW since there is no direct pathway to these sampling points.