WORK PLANS_FILE 1 - Laserfiche WebLink

Home Browse Search

At the proposed location, a pair of borings will be advanced with the CPT rig. The first boring will be used to record tip resistance, sleeve friction and pore water pressure at five-centimeter intervals. These data will be processed and interpreted in the field. Based on the interpreted soil and groundwater parameters, the second soil boring will be advanced to specific depths for discrete soil and groundwater sample collection, Since the soil samples collected at 65 feet from the borings for MW-1, MW-2 and MW-3 did not contain detectable concentrations of petroleum hydrocarbons, a soil sample will also be collected at 65 feet bgs from the CPT location. If field observations suggest that this soil sample may contain petroleum hydrocarbons, additional soil samples may be collected at approximately 80 and 95 feet bgs. All soil samples will be collected into stainless steel sleeves using a push-driven soil sampling methodology. The soil samples will be capped with Teflona film and plastic end caps, and transported in an iced cooler with chain-of-custody documentation to a state of California-certified hazardous waste testing laboratory for analysis. Each of the soil samples will be analyzed on a standard turn-around time for TPH-as-jet fuel, TPH-as-gasoline and BTEX by EPA Method 8020/8015M, and for MTBE, DIPE, ETBE, TAME, and TBA by EPA Method 8260B. Groundwater samples will be collected with a Hydropunche from up to two significant permeable groundwater-bearing intervals below the groundwater table. After deployment of the Hydropunch at each sample depth, it will be checked for leakage, prior to exposing the sampling screen. All groundwater samples will be collected into laboratory-supplied containers using a decontaminated stainless steel baiter. The groundwater samples will be transported in an iced cooler with chain-of-custody documentation to-a state of California certified hazardous waste testing laboratory. The lab will analyze each groundwater sample for TPH-as-jet fuel, TPH-as- gasoline and BTE X by EPA Method 8020/80 , and for MTBE, DIPE, ETBE, TAME, and TBA by EPA Method 6260 ; Following sample collection, the CPT and Hydropunch borings,will be sealed with bentonite grout, The grout will be placed to the bottom of the boreholes using a tremie pipe. 3.4 Waste Storage and Disposal All waste soil cuttings generated during drilling will be stockpiled using a base and cover of plastic sheeting, and stored temporarily on-site, pending waste profiling and proper disposition. Equipment rinsate water and purged groundwater will be contained in 55 gallon drums for temporary on-site storage, pending waste profiling and proper disposition.