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SECTION 3 SUBSURFACE EXPLORATION Subsurface exploration was conducted using a direct push drill rig to advance four borings to a maximum depth of 16 feet bgs each for sampling soil and groundwater. Further, composite samples of near surface soils were collected in three areas of the property. The approximate locations of the borings and composite sampling areas are shown in Figure 2. 3.1 FIELD METHODOLOGIES On 22 August 2000, three direct push soil borings were completed to a depth of 12 feet below ground surface (bgs) and one direct push soil boring was completed to a depth of 16 feet bgs by Precision Sampling of San Rafael, California under the supervision of WESTON. Soil was sampled continuously in a sampling tube fitted with acrylic liners. The borings were logged in accordance with the Unified Soil Classification System (USCS). Copies of the boring logs are included in Appendix A. Samples from the interval between 4.5 and 5 feet bgs were capped with teflon tape and plastic end caps, labeled, and then preserved in a cooler on ice for laboratory analysis. Soil samples from the borings were labeled according to the convention "SB-n-d," where "SB" signifies "soil boring," "n" refers to the boring number, and "d" indicates the approximate depth in feet bgs. A groundwater grab sample was collected from each boring upon removal of the soil probe/sampling tube. This was accomplished by inserting a temporary well screen and casing into the borehole and collecting a grab sample within the temporary well, using a new, disposable, polyethylene bailer. Groundwater samples were carefully decanted from the bailer into appropriate sample containers, labeled, and then placed in a cooler on ice. Groundwater grab samples were labeled according to the convention "GW-n," where "GW" signifies "groundwater," and"n" refers to the boring number. For evaluation of potential impacts from pesticides and herbicides to surficial soil, composite soil samples were collected from three areas of the site. The locations of the three sample areas are shown in Figure 2. Eight discrete soil samples from the upper six inches of soil within each of the three composite sample areas were collected using a trowel. The eight discrete sample locations were dispersed randomly within each composite sampling area. Soil from the eight discrete samples was combined together and the resulting mixture was placed into glass sample jars. Each of the three composite sample containers were labeled and placed in a cooler on ice. The composite soil samples were labeled according to the convention "CS-n," where "CS" signifies "composite," and "n"refers to the area sampled. All sampling equipment was decontaminated between sample locations by washing with alconox detergent solution and rinsing with deionized water. The direct push borings were abandoned by filling with bentonite cement grout as directed by the San Joaquin County Environmental Health Department. Soil cuttings were transported off-site and disposed of by Precision Drilling. G:home\clarkeb\projects\homedepo\tracy\addpI&2.doc 3-1 July 1999