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� v 0 A S S O C I A T E S I N C boring/well construction logs contained in Appendix B. Soil borings MW2, MW3, MW4, and MW5 were advanced and completed as groundwater monitoring wells. ' A sixth boring was initiated adjacent to the school, west of the UST. However, an underground electrical line was encountered and at that time drilling was halted. Verbal permission was given ' by Mr. Jeff Wong of PHS/EHD to abandon the boring. The underground utility was subsequently repaired. 22.2 Soil Sample Analysis Selected soil samples were placed on ice, and transported under chain-of-custody to Argon ' Laboratories, 3037 Fifth St., Ceres, CA (FLAP #2359) for analysis. All soil samples were analyzed for total petroleum hydrocarbons as gasoline (TPHg) and benzene, toluene, ethylbenzene, and xylenes (BTEX) utilizing EPA 8015 (modified) and 8020 methodologies, and oxygenate fuel additives utilizing EPA 8260 methodology. Soil samples from borings MW2 at 10.5 feet, MW3 at 10 feet, MW4 at 15 feet and MW5 at 10 feet were analyzed for lead by EPA ' 7420 methodology. The analytical results for soil samples are summarized in Table 1. Laboratory data sheets and chain-of-custody documentation are included in Appendix C. 2„.3 Groundwater Monitoring Well Construction Soil borings MW2, MW3, MW4, and MW5 were subsequently completed as groundwater ' monitoring wells to assess the lateral and vertical extent of impacted groundwater, if any, beneath the site. Wells MW3, MW4, and MW5 were constructed with 2-inch PVC casing to depths of 27, 30, and 27 feet bgs, respectively. The screened intervals of the wells were positioned from approximately 5 feet above to 10 feet below the encountered water table to allow for seasonal water level fluctuations. Monitoring well MW2 was constructed with 2 inch PVC casing to a depth of 35 feet bgs. The screened interval was set at five feet. The screen slot size utilized at all the monitoring wells is 0.020-inch. All wells were each secured with a traffic rated utility box and a paddle lock. The well construction details are depicted on the well logs contained in Appendix B. 2_4 Monitoring Well Development Groundwater monitoring wells MW2 through MW5 were developed on February 22, 2001. The wells were purged until the extracted water was relatively sediment free. Development/purge logs are included in Appendix C. Purge water was temporarily stored on site in 55-gallon drums. After fluid levels had been allowed to stabilize, groundwater level was obtained from all ' monitoring wells. Groundwater levels were taken on February 22, 2001, utilizing an electronic water probe capable of measuring with an accuracy of 1/100 of a foot. Groundwater elevation . data are presented in Table 3. w:\17292VeponalSup_subsurf invesLdoc 3