AP2400420 (4) - Laserfiche WebLink

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Scope Sampling procedures will generally conform to the requirements of the San Joaquin County Environmental Health Department (SJCEHD), the SWRCB, the Department of Toxic Substances Control (DTSC), and the United States Environmental Protection Agency (EPA). A state-certified laboratory will analyze the samples and the project will be performed under the responsible charge of a qualified Partner representative. Laboratory results will be compared with the San Francisco Bay San Francisco Bay Regional Water Quality Control Board (RWQCB) Environmental Screening Levels (ESLs). Partner will perform the following tasks for the Phase II Subsurface Investigation: • Prepare a site-specific health and safety plan; • Notify Underground Service Alert (USA) a minimum of two business days prior to drilling activities to clear public utilities; • Secure the necessary drilling permit from the SJCEHD. Permit acquisition will involve submitting a completed application and site plan to the SJCEHD for review and approval and remitting the necessary fees.The turnaround time of the SJCEHD to issue the permit is expected to be no more than two weeks; • Notify the applicable regulatory agencies a minimum of 48 hours prior to drilling/backfilling activities; • Clear the boreholes of utility lines through a geophysical survey. Boring placement will be modified as necessary based on the geophysical survey results to avoid damaging underground features. Additionally, to the extent practical based on subsurface lithology, clear boring location using hand tools; • Advance a total of 13 borings (131 through B13) throughout the subject property according to the following schedule: Area of Concern Number of Terminal Depth Matrix Sampling Depth Borings (feet bgs) (feet bgs) Trench Drain in Soil 1, 2.5, 5 Building1 1 5.5 Soil Gas 5 Spray Paint Booth and Hazardous Soil 1, 2.5, 5 Materials in 4 5.5 Soil Gas 5 Buildings 3 and 4 Hazardous Materials South of 1 5.5 Soil 1, 2.5, 5 Soil Gas 5 Buildings 3 Former Excavation Soil 1, 2.5, 5 Areas 5 5 Soil Gas 5 The final soil gas screening depth at each borehole will be adjusted based on the encountered lithology. In general, probes will be screened within coarser-grained materials and clayey/saturated intervals will be avoided,if possible; • Drilling and sampling equipment will be pre-cleaned prior to arriving on-site. Downhole equipment and materials will be decontaminated in a detergent/tap water and double-rinsed with tap water or with a pressure washer between samples and/or borings to reduce the potential for cross-contamination. Soil samples will be collected using a 4-foot long by 2.25-inch diameter MacroCore sampler with a 4-foot long acetate liner, which was advanced by the direct-push drill rig using 4-foot long by 1.5-inch diameter drill rods.The sampler will be driven into the subsurface to allow undisturbed soil to enter the open MacroCore barrel and retrieved in 4-foot intervals to recover the soil-filled liners. A lengthwise section of each acetate liner was removed with a splitting tool to expose the soil. The soil column was Page 3 PARTNER