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1 8 LFR • To assess the presence of chlorinated solvents north of previous locations MIP-3, MIP-8, and MIP-10 (see Figure 1) using MIP technology. • To simultaneously collect EC or CPT data to obtain detailed lithologic data. • To collect five grab groundwater samples to calibrate/validate the MIP data. • Together, the MIP and EC/CPT data will be used to refine the sparge well design layout, specifically the need for additional angled sparge wells beneath Benjamin Holt Road. The specific tasks are discussed below. Scope of Work Membrane Interface Probe Investigation To achieve the objectives stated above, LFR proposes to advance MIP borings at six locations (MIP-22 through MIP-27, 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 80 feet below ground surface (bgs) in the A zone (Figure 1). Eighty feet bgs is presented herein as a `target' depth; the MIP boring will be pushed past 80 feet 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 six boring locations. CPT/EC-based lithologic logs and MIP-derived concentration logs will be generated based on the data obtained from each boring. Each boring 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 volatilized 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. wp-Linco1n-M1P-0c1064)6750 do dch 2