COMPLIANCE INFO_1993-1994 - Laserfiche WebLink

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City of Stockton TL 394-0027-02 March 10, 1994 Page 7 APPENDIX A STANDARD OPERATING PROCEDURES The standard operating procedures for drilling and soil sampling, decontamination, installation of soil gas probes, and disposal of rinsate and soil cuttings are described in this appendix. The following procedures are supervised under the direction of a California registered geologist. A-1 Drilling and Soil Sampling: Subsurface assessment permits will be filed with the San Joaquin County Environmental Health Department (SJCDEH) before conducting field operations. Underground Service Alert will be notified at least 48 hours prior to initiation of field activities. The soil borings will be drilled using a Central Mine Equipment Company 75 truck-mounted drill rig equipped with 6-5/8-inch outside diameter, continuous-flight, hollow-stem augers. Twining is a licensed drilling contractor under C-57 classification (Contractor's License No. 506159) . The soil borings will be drilled under the direction of a Twining geologist. Soils encountered during drilling will be logged consistent with the Unified Soil Classification System. The soil boring logs will note soil types encountered at depth including consistency, soil moisture, particle size, color, and other distinguishing features. Soil samples will be collected using a 1-1/2-inch inside diameter split-spoon sampler. Samples will be obtained by attaching the sampler to the drive rod, followed by driving the sampler into undisturbed soil below the lead auger with a 140-pound hammer that is continuously dropped 30 inches until the sampler penetrates 18- inches of soil . The number of drops will be recorded for each six- inch increment the sampler is driven into the soil and recorded on the field log of soil borings . The values for the bottom two six- inch increments will be added together to obtain a standard penetration resistance value for each sample. Upon completion of the drilling and soil sampling, each borehole will be completed as a soil gas probe. If a boring is not completed as a gas probe, it will be pressure grouted with a six- sack sand-cement slurry with approximately 5 percent bentonite to site grade. Soil cuttings from the borings will be sealed in United States Department of Transportation (DOT) approved 55-gallon steel drums . The drums will be labeled with information on the source of their contents and stored on site in a location remote from public access. The disposal of the drill cuttings is discussed below.