ARCHIVED REPORTS_MONITORING WELL M-10 INVESTIGATION REPORT 2010

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M-10A Investigation Report November 30, 2010 Nestle USA, Inc., Ripon, California traffic control plan safety requirements while completing work in City of Ripon right-of- ways, parking lots, and alleys. Safety requirements included cones, traffic warning signals, lane closure signs, and flagmen. 3.1.4 CITY OF RIPON PERMIT SITE WALK On September 3, Mr. James Pease from the City of Ripon met with ECM personnel to conduct a site walk and field review the boring locations which were proposed in City of Ripon right-of-ways. As a result of this review, the City of Ripon requested a shift in the location of two CPT borings. This resulted in a deviation from the boring spacing originally proposed in the Work Plan. CPT-21 was moved approximately 120 feet to the east of its original proposed location. The new location placed CPT-21 on a currently unused City of Ripon-owned parcel, and removed it from a City of Ripon parking lot. CPT-23 was moved approximately 100 feet to the west of its original proposed location, which placed it along the edge of a City of Ripon parking lot, and away from an alley entrance and associated alley parking area. 3.1.5 SUBSURFACE UTILITY CLEARANCE ECM obtained utility mark-out tickets for all CPT locations from Underground Service Alert (USA) for utility clearance. Some of the tickets covered multiple boring locations. ECM also contracted with Subtronic Corporation (Subtronic), a private subsurface utility locating company, to complete a subsurface utility screening at all locations. Subtronic completed initial utility clearance activities on September 3, 2010. Subtronic provided additional utility clearance on September 22, after CPT-24 was relocated due to conflict with utilities and private parking spots. 3.2 CPT DRILLING Lankelma conducted all of the CPT drilling for this investigation. CPT drilling includes the direct push advancement of an electronic measuring device into the subsurface. Prior to advancing any mechanized equipment, Lankelma technicians manually cleared the first four feet of soil using a hand auger to confirm the absence of shallow utilities. The CPT data collected during drilling include continuous logs of cone tip resistance, friction sleeve resistance (side friction created by subsurface materials), dynamic pore pressure and the computed friction ratio. This information is correlated to engineering soil classification s6. The lithologic data obtained from the CPT drilling is then correlated with lithologic information obtained from nearby boreholes/well logs to verify the CPT results. 3.3 GROUNDWATER SAMPLING Upon selecting the target intervals for groundwater samples at each CPT location, Lankelma advanced a companion borehole directly adjacent to the CPT borehole. The hydraulic ram of the CPT rig was used to advance a Hydropunch° sampler to the targeted sampling depths. At the desired depth, the drill casing was retracted to expose the screened interval of the sampling device to allow groundwater to enter the sampler. ECM then collected a groundwater sample with a decontaminated stainless steel bailer. Samples were collected in laboratory-supplied 40 milliliter volatile collection vials, sealed airtight, and placed on ice for transport by courier to TestAmerica Analytical Testing 5