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S 3 • a � 5 i I - APPENDIX A GENERAL FIELD PROCEDURES ' A description of the general field procedures used during site',investigation and monitoring activities is presented below. For an over-view of protocol, refer to the appropriate section(s). t r DRILLING AND SOIL SAMPLING Soil borings were advanced using a truck-mounted GeoprobeT"'rig. Borings that were not completed as monitoring wells were grouted to the ground surface with a Bement slurry, which was placed in each h boring using a tremie pipe. Soil samples were obtained for sail 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 314-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 uisert is filled approximately 113 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 E with the Unified Soil CIassification ,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 poisible future testing. I i k Ik w 7 _