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Monte Vista Entitlement,Inc. Phase I ESA Peer Review and Limited Phase II ESA Report November 18,2003 Page 3 Condor conducted a limited investigation into potential impact to soil beneath parcel 149-200-10 by hydrocarbons from the suspected UST on the adjacent parcel. A work plan and a drilling permit application for two direct push soil borings were prepared by Condor and submitted to the San Joaquin County Environmental Health Department (SJCEHD). The work plan and permit were approved by Mr. Michael Infiirna of the SJCEHD. Condor received the drilling permit prior to initiating any fieldwork. The proposed soil boring locations were marked with white paint and Underground Service Alert (USA) was notified 72 hours in advance of the fieldwork to locate and identify underground utilities in and near the work area. However, because the proposed boring locations were on private property, some utilities contacted by USA did not mark their lines past property boundaries and on to the site. Therefore, it was the responsibility of the property owner to locate and identify underground utilities in and near the work area. The SJCEHD was notified of the fieldwork schedule 48 hours in advance. A Condor geologist was on site to.supervise the work. Prior to commencement of fieldwork, a tailgate safety meeting was held and a site-specific Health and Safety Plan was discussed with, and presented to, all field personnel for their signatures. The investigation included the advancement of two direct push borings (TB-1 and TB-2) on July 31, 2002. The boring locations are shown in Figure 4, attached. Both borings were advanced to a depth of approximately 25 feet below ground surface (bgs). The direct push borings were hydraulically advanced using a 1.5-inch diameter conical bit. The bit and associated push rods were thoroughly cleaned before each borehole was advanced using laboratory-grade, non-phosphate detergent and hydrocarbon-free water and double-rinsed with hydrocarbon-free water. Upon completion of the drilling and sampling, the boreholes were backfilled with neat cement. The cement was trc-mied into the boreholes to avoid bridging. Soil samples were collected from the borings using a 2-inch outside diameter, 4-foot long core barrel, fitted with a clean, single use, acetate liner. During the soil sampling, the core barrel was driven continuously in four-foot intervals. After the core barrel was driven four .feet, the core barrel was withdrawn and the sample was removed. The sample liner was extracted from the core barrel and used for geologic logging and field observations. The core barrel was cleaned with laboratory-grade, non- phosphate detergent and hydrocarbon-free water and double-rinsed with hydrocarbon-free water. A new unused acetate liner was placed in the core barrel and the process was .repeated. All soil samples were Lr logged according to the Unified Soil Classification System (USCS). Geologic logs were prepared containing field observations including soil type, estimated moisture content, photoionization detector (PID) measurements, and the presence of staining or odor. Soil encountered in both borings was similar. A typical geologic log for the borings is attached. No obvious hydrocarbon contamination was noted in any of the cores, so soil samples from 15 and 20 feet bgs from each boring were cut from the liners for laboratory analyses. The soil samples were retained, undisturbed, in the liners. The liners were sealed at the ends with Teflon sheeting, capped, and labeled. The samples were stored in a cooler chilled with Blue Ice and delivered under chain-of-custody procedures to Argon Laboratories of Ceres, California. The samples were analyzed using U.S. EPA and California approved methods. The two soil samples collected from 15 feet bgs were composited by the laboratory for analyses. The two soil samples collected from 20 feet bgs were also composited by the laboratory. The two composite samples were analyzed for benzene, toluene, ethy.lbenzene, and toluene (BTEX) by EPA Method 8020A and for total petroleum hydrocarbons quantified as gasoline, diesel, kerosene, and motor oil (TPH-G, TPH-D, TAH-K, T.PH-MO)by EPA Method 8015M. None of the analytes were detected at concentrations at or above the laboratory reported detection limits in either sample. Laboratory analytical results are presented in Table 1 on the next page. Copies of the laboratory analytical reports and the chain-of-custody form are attached. �"'a CONDOR