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APPENDIX A GENERAL FIELD PROCEDURES A description of the general field procedures used during site investigation and monitoring activities is presented below. For an overview of protocol, refer to the appropriate section(s). DRILLING AND SOIL SAMPLING Soil borings were advanced using a truck-mounted Geoprobe�m rig. Borings that were not completed as monitoring wells were grouted to the ground surface with a cement slurry, which was placed in each boring using a tremie pipe. Soil samples were obtained for soil description, field hydrocarbon vapor screening, and possible laboratory analysis. Soil samples were retrieved from the borings by one of two methods: 1)continuously, using a 1 and 3/4-inch diameter 4-foot-long, continuous-core macro core sampler lined with acetate or brass sleeves, or; 2) at specific intervals using an 1-inch diameter 2-foot-long, continuous-core micro core sampler lined with acetate or brass sleeves , each advanced into the soil with a weighted or vibrating hammer. During drilling activities, soil adjacent to the laboratory sample is screened for combustible vapors using a combustible gas indicator (CGI) or equivalent field instrument. For each hydrocarbon vapor screening event, a 6-inch-long by 2.5-inch-diameter sample insert is filled approximately 1/3 full with the soil sample, capped at both ends, and shaken. The probe is then inserted through a small opening in the cap, and a reading is taken after approximately 15 seconds and recorded on the boring log. The remaining soil recovered is removed from the sample insert or sampler, and described in accordance with the Unified Soil Classification System. For each sampling interval, field estimates of soil type, density/consistency, moisture, color, and grading were recorded on the boring logs. SOIL SAMPLE HANDLING Upon retrieval, soil samples were immediately removed from the sampler, sealed with Teflon sheeting and polyurethane caps, and wrapped with tape. Each sample is labeled with the project number, boring/well number, sample depth, geologist's initials, and date of collection. After the samples have been labeled and documented in the chain of custody record, they were placed in a cooler with ice at approximately 4 degrees Celsius (°C) prior to and during transport to a state-certified laboratory for analysis. Samples not selected for immediate analysis may be transported in a cooler with ice and archived in a frostless refrigerator at approximately 4°C for possible future testing.