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APPENDIX B <br /> FIELD PROCEDURES <br /> B.1 WELL/BORING DRILLING PROCEDURES <br /> 1. The boring locations will be cleared using hand tools to excavate down to approximately <br /> 4 feet bgs in order to avoid any subsurface obstructions prior to the use of any mechanized <br /> equipment. If an obstruction is encountered, the boring will be relocated. The abandoned <br /> borehole will be backfilled, compacted and resurface to match the surrounding surface. <br /> 2. Borings CPT-IA and CPT-IB will be advanced to 80 feet bgs using a 30-ton CPT rig, and <br /> boring BSW-I will be advanced to 80 feet bgs using a limited access CME-75 drilling rig <br /> equipped with 8-inch diameter hollow stem augers. The borings will be drilled by C-57 <br /> licensed drilling companies subcontracted to FREY. <br /> 3. Soil samples will be collected from soil boring CPT-1B using dual-tube sampling <br /> methodology in acetate liners at 5-foot intervals from 65 feet bgs to the bottom of the <br /> borehole. <br /> 4. Soil descriptions, sample type and depth, and related drilling information will be recorded <br /> on a boring log under the supervision of a State Certified Engineering Geologist and/or <br /> State-Registered Geologist from FREY. <br /> B.2 HEAD SPACE ANALYSIS <br /> 1. Soil samples collected from soil boring CPT-1B and select soil cuttings from boring BSW- <br /> 1 will be placed into a ziplock bag, immediately sealed, and will be allowed to equilibrate <br /> for approximately 15 minutes. <br /> 2. The sample will then be connected to a RKI GX-6000 photo ionization detector/organic <br /> vapor analyzer(PID/OVA) and the concentration will be recorded in ppm. <br /> B.3 BIOSPARGE WELL INSTALLATION PROCEDURES <br /> 1. BSW-1 will be constructed of 2-inch diameter flush jointed, threaded PVC. Slot openings <br /> will be 0.020 inch. <br /> 2. The well will be screened between feet bgs 75 to 80 feet bgs. Blank casing will be placed <br /> from the top of the screen to just below the ground surface. <br /> 3. The well casing of the air sparge well will be constructed inside the 8-inch HSAs. <br /> 4. The annulus around the screened interval of the well will be backfilled with a screened- <br /> washed sand. Sand backfill material will be placed to a depth of approximately 3 foot above <br /> the screened section of the well. <br /> 5. Hydrated bentonite pellets will be placed immediately above the sand pack and extend to <br /> approximately 3 feet above the sandpack. The annulus above the bentonite seal will <br /> backfilled with neat cement to near the ground surface. <br /> 6. A traffic-rated well box will be placed above the well casing and set in concrete. The well <br /> box will be raised slightly above the ground surface to minimize surface water infiltration. <br /> BA WELL DEVELOPMENT PROCEDURES <br /> 1. Newly-installed biosparge well BSW-1 will be developed by surging and pumping with a <br /> submersible pump. <br /> 2. Temperature, PH, conductivity, and total dissolved solids (TDS) will be measured during <br /> well development. <br /> 3. Well purging will be continued until the temperature,pH, conductivity, and TDS readings <br /> remain approximately stable. <br /> 4. Water recovered from the wells will be recycled at Instrat in Rio Vista, California. <br /> FREY Environmental, Inc. Project No. 1175-01 <br />