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BUR Scope of Work Membrane Interface Probe Investigation To achieve the objectives stated above, LFR proposes to advance MIP borings at six locations (MIP-16 through MIP-21, Figure 1). The MIP borings will be advanced by a California-licensed drilling contractor, under the direct supervision of LFR personnel. The borings will be advanced using a 30-ton direct-push (CPT-type) drill rig to depths of approximately 60 feet bgs in the A zone and 100 feet bgs in the B zone (Figure 1). Sixty feet bgs and 100 feet bgs are presented herein as "target" depths; the MIP borings will be pushed past the target depths of 100 feet bgs if real-time field data indicate the presence of contaminants at the bottom of the boring. The MIP probe will also be equipped with either a CPT or an EC detector to simultaneously collect data from which lithology is inferred. Continuous MIP and CPT/EC measurements will be made at each of the eight boring locations. CPT/EC-based lithologic logs and MIP-derived concentration logs will be generated based on the data obtained from each of the borings. Each of the borings will be grouted, from the bottom to the surface, with neat cement after completion. The MIP is advanced using a standard string of 1.25- or 1.5-inch rods and a direct-push probing unit. Before the probe is advanced, the tubing that houses the carrier gas and conductivity cable is connected to the MIP tool and is strung through the probe rod. The rods are then loaded on a rod cart or fixed tool rack for easy dispensing and storage. As the probe is driven to depth, the advancement is stopped at desired intervals (typically 6 inches) to gather volatile organic compound (VOC) data. Conductivity logging data are gathered on a continuous basis. At the desired intervals, the permeable membrane interface on the wall of the probe is heated. Any VOCs that are exposed to the membrane are volatized and picked up by the carrier gas behind the membrane, which in turn delivers the gas to the gas chromatograph detector at the surface (typically an electron capture detector (ECD), photoionization detector, and/or flame ionization detector). A stringpot, which is mounted on the probe, senses movement of the probe and measures depth and speed. The data are stored in spreadsheet-compatible format for later graphing and analysis. The gas chromatographs provide total VOC readings and are also stored for plotting. Following the collection of the MIP data, a Hydropunch sampler will be advanced to collect grab groundwater samples from the A-zone and B-zone aquifers in four boring locations. The groundwater samples will be collected using a hydraulically driven temporary piezometer consisting of a hollow-rod assembly with a 3-foot-long stainless steel screen attached at the leading end of the assembly (Hydropunch). The piezometer will be advanced to the desired depth interval based upon the CPT-derived lithology and the MIP' s ECD results. At the selected depths, the rod assembly will then be retracted to raise the outer piezometer sleeve, exposing the screen and allowing groundwater to pass through the screen into the piezometer. Each groundwater sample will be collected by lowering a Teflon or stainless steel bailer through the hollow-push rods into the piezometer screen. In addition to the grab groundwater samples collected near each MIP boring, groundwater samples will be collected from four piezometer wells that are screened in the coarse-grained sand lense of interest, PZ-013A-1, PZ-013A-2, PZ-014A-1, and PZ-014A-2. The wp-lincoln-MIP-ApA6-06750.dw:lfi 3