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C A M B R I A Ms.Lori Duncan November 18,2005 investigation in our January 6, 2003 Site Investigation and Third Quarter 2003 Groundwater Monitoring Report. 2003 Site Conceptual Model (SCM): Cambria submitted a Site Conceptual Model/Site Investigation Work Plan on October 3, 2003. In the SCM, Cambria recommended installing a well downgradient of the USTs, installing a deep groundwater monitoring well, and performing dual-phase extraction(DPE) and SVE in the former UST complex. 2004 Well Installation: During February 2004, Cambria installed one shallow off-site well (MW-12) in the parking lot east of the site and one deep on-site well (MW-13). No TPHg, © BTEX, or fuel oxygenates were detected in well borings MW-12 and MW-13. Soil results from MW-12 indicate that subsurface soil across Pacific Avenue east of the existing UST complex is not impacted by gasoline constituents. Cambria's April 9, 2004 Site Investigation and First Quarter 2004 Groundwater Monitoring Report details this investigation. 2004 Interim DPE: During a 5-day period in June 2004, Cambria performed DPE using well VEW-2 and SVE using well VEW-1. Cambria estimates that approximately 200 pounds of vapor-phase TPHg and 2.31 pounds of vapor-phase benzene were removed from wells VEW-1 and VEW-2 during the course of this interim remediation. In addition, 3,486 gallons of groundwater were extracted from VEW-2, removing approximately 3.49 pounds of liquid-phase TPHg and 0.12 pounds of liquid-phase benzene from the subsurface. Cambria's February 9,2005 Interim Remediation Report further describes these activities. 2005 Corrective Action Plan (CAP): Cambria submitted a Corrective Action Plan and Risk- Based Corrective Action Analysis on September 9, 200. The CAP recommended DPE as the preferred remedial technology based on feasibility and cost-effectiveness and proposed groundwater and soil cleanup goals. In the September 15, 2005 letter approving the CAP, SCJEHD did not approve the proposed groundwater and soil cleanup goals. Instead, SJCEHD requested that Shell use maximum contaminant levels or water quality objectives in the Regional Water Quality Control Board basin plan as cleanup goals. Groundwater Monitoring Program: There are currently six on-site groundwater monitoring wells (MW-1 through MW-4, MW-13 and VEW-2), one on-site SVE well (VEW-1), and eight off-site groundwater monitoring wells (MW-5 through MW-12). VEW-2 was originally installed as an SVE well, and well MW-13 is screened deeper than the other wells. Wells MW-1 through MW-8, MW-12, MW-13, and VEW-2 are sampled quarterly, well MW-9 is sampled semi- annually during the first and third quarters, and wells MW-10 and MW-11 are sampled annually during the third quarter. Well VEW-1 is dry. During the third quarter 2005 sampling event,TPHg was detected in wells MW-3, MW-4,MW-6 through MW-11, and VEW-2 at concentrations ranging from 110 to 84,000 ppb. The laboratory noted that the TPHg reported for wells MW-10 and MW-11 reflects individual or discrete 4