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4 <br /> On March 24, 25, and 26, and May 20, 2004, three soil borings (GPI, GP2 and GP3) were <br /> advanced at the site in the vicinity of the former USTs to evaluate the lateral extent of petroleum <br /> affected soil and groundwater <br /> On March 29 and April 2, 2004, two CPT borings (CPT1 and CPT2) were advanced at the site in <br /> the vicinity of the former USTs to evaluate the vertical extent of petroleum affected soil and <br /> groundwater The GP and CPT borings are discussed in ATC's Supplemental Subsurface <br /> Investigation at Three Palms Grocery, dated October 18, 2004 All analytical results of the water <br /> samples are summarized in Table 1 <br /> SAMPLING ACTIVITIES <br /> ATC performed quarterly groundwater monitoring on April 11, 2005 Field work included <br /> gauging the depth to water in the site's domestic well (DW) and the three groundwater <br /> monitoring wells (MWI through MW3) <br /> Groundwater samples collected from MW-1, MW-2, MW-3, and the domestic well were placed <br /> on ice and transported under chain-of-custody to State-certified Argon Laboratories, Inc , <br /> Environmental Laboratory Accreditation Program (ELAP Certification No 2359), in Ceres, <br /> California for chemical analysis All samples were analyzed for BTEX by EPA method 802113, <br /> . TPHg by EPA method Modified 801513, and oxygenate fuel additives, including and methyl <br /> tertiary butyl ether (MTBE), ethyl tertiary butyl ether (ETBE) di-isopropyl ether (DIPE), tertiary <br /> amyl ether (TAME), tertiary butyl ether (TBA), 1,2-dichloroethane (1,2-DCA), and 1,2- <br /> dibromoethane (EDB) utilizing EPA method 8260B <br /> GROUNDWATER FLOW DIRECTION <br /> Depth to water measurements were recorded on April 11, 2005 from monitoring wells MWI <br /> through MW3 (Table 2) Since measurements were taken in July of 2004, MWI, MW2 and <br /> MW3 have been dry, therefore, groundwater gradient and direction in the uppermost aquifer <br /> beneath the site were unmeasurable As of the most recent measurements, all three wells contain <br /> water, and a groundwater gradient has been reestablished (Figure 3) MWI and MW2 are <br /> screened at between 71 and 91 feet below ground surface (bgs) MW3 is screened at between <br /> 71 5 and 91 5 feet bgs A depth to water measurement in DW was recorded as 88 62 feet below <br /> the top of the casing This represents an increase of 4 24 feet since last monitoring occurred on <br /> January 14, 2005 Historically, groundwater beneath the site generally flowed in a northeasterly <br /> direction <br /> ANALYTICAL RESULTS <br /> Monitoring wells MWI, MW2 and MW3 were sampled on April 11, 2005 Field notes are <br /> included in Appendix A ATC collected a water sample from the sampling port of the on-site <br /> • domestic well (DW) after measuring depth to water and purging approximately 120 gallons <br /> S 114885Veportsl2gtr2005 doc 3 <br />