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S E C ® R County), and a conducting a door-to-door field survey in search of any wells or other sensitive receptors within 1,000 feet of the site Four wells were identified within the surveyed area, one municipal well and three domestic wells The domestic well was identified as Colonial Heights municipal water supply well #3 (Well DW-3) The location of Well DW-3 was verified in the field and surveyed, and is situated 260 feet south of the site, on the south bank of Mosher Slough, which borders the intersection of Thornton Road and Davis Road Three additional water supply wells in the area were identified One well was identified at Bear Creek Veterinarian Hospital (Well DW-2), located at 8728 Thornton Road Well DW-2 is located 444 feet north of the site Another well is located at a residence (Well DW-4), located at 8732 Davis Road (180 feet north of the site) SECOR field staff located what appeared to be a domestic water supply well (Well DW-1) on the property located at 8855 Thornton Road that is 281 feet northwest of the site The resident was not available to confirm the existence of the well, and a well survey form was not completed by the property owner, however, the possible domestic well was housed in a similar enclosure as the previously identified wells in the field CURRENT ASSESSMENT ACTIVITIES No assessment activities were conducted this quarter MONITORING AND SAMPLING TRC's Groundwater Monitoring Report dated November 8, 2005 is included as Attachment 1, including Tables 1- 3, Figures 1 — 5A/5B, and field data sheets and groundwater analytical reports The site has been monitored and sampled since 1St quarter, 1999 From 1999 to the present the Site has been monitored/sampled quarterly Currently, 10 wells (MW-1 through MW-10) are monitored and sampled on a quarterly basis Samples are analyzed for total purgeable petroleum hydrocarbons (TPPH), benzene, toluene, ethylbenzene, and total xylenes (collectively known as BTEX), and fuel oxygenates, including methyl tertiary butyl ether (MtBE), tertiary amyl methyl ether (TAME), di-isopropyl ether (DIPE), ethyl tertiary butyl ether (EtBE), tertiary butyl alcohol (TBA), ethylene dibromide (EDB), 1,2-dichloroethane (1,2-DCA), and ethanol by EPA Method 8260B Based on TRC's Quarterly Monitoring Report dated November 8, 2005, the following maximum concentrations were reported as follows TPPH <5000 pg/L Benzene <50 pg/L MTBE 9,400 pg/L (MW-4) MtBE concentration trend in the shallow zone is stable to increasing Groundwater direction in the shallow zone was to the northeast and in the deep zone was to the north at 0 003 ft/ft and 0 01 ft/ft, respectively REMEDIATION STATUS • An SVE pilot test was conducted during the 2n1 Quarter 2005 A report documenting the Pilot test results was submitted in the 3`d Quarter 2005 Interim ozone sparging will begin upon approved by the RWQCB