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Clayton EWRONMENTAL CONSULTANTS 3.0 INVESTIGATION ACTIVITIES Clayton's soil and groundwater assessment cons' ted of three distinct activities: field procedures, field work, and laboratory analyses. These activities were performed to meet the existing site constraints and the investigation objectives. 3.1 FIELD PROCEDURES Clayton used specific field procedures to manag the field activities used during the subsurface soil investigation. These procedures were used for sampling the soil boreholes, collecting and analyzing the soil samples, and decontaminating equipment to minimize the potential for cross contamination. A copy of the permit to perform the work is in Appendix B. 3.1.1 Soil Sampling A 31/2-inch diameter hand auger was used to drill three oreholes for the soil investigation. The boreholes were drilled in the below-grade landscaped area which surrounds the basement community room to the north and to the west. Borehole BH- 1 was drilled in the concrete sidewalk by the northeastern corner of the room. Borehole BH-2 was drilled in the landscaped arm by the northwestern corner of the room. Borehole BH-3 was drilled in the concrete sidewalk by the southwest corner of the room. The auger was advanced in the borehole until the desired depth �r sampling was reached. At the sampling depth, the contents of the auger were packed into a 2-inch diameter stainless steel tube by using a hand trowel. The ends of the tube were immediately covered with Teflon" sheeting and plastic end caps, then sealed with Scotch' 33+ electrical✓tape. The tube was then labeled, inserted in a self-sealing plastic bag, and placed on ice in an ice chest for transportation to a State of California, Department of Health Services, certi ied laboratory for analyses. Standard chain-of-custody procedures were followed. A portion of the auger's contents was field eval ated for volatile organic compounds (VOCs) using an organic vapor analysis (OVA) ieadspace technique. A portion of the soil was put into a self-sealing plastic bag an I allowed to volatilize in direct sunlight for a minimum of 30 minutes. A senso tip of a photoionization detector (PID) was then inserted through the plastic bag. The concentration of VOCs in the plastic bag was measured with the PID meter and recorded on the borehole logs. The boreholes and soil samples were described by a Clayton geologist under the supervision of a California registered geologist using the Unified So� Classification System (USCS). The PID meter was also used W measure breathing zone and 2 4014.00.REP CON FIDENTIAL AND PRIVILEGED