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' Mobilization and Permitting Appropriate permits will be obtained from San Joaquin County Environmental Health ' Department, if required,prior to any well drilling, well abandonment, or soil boring activities being conducted in the field. ' Prior to drilling, the drill rig and all down-hole tools will be cleaned using a high- pressure, hot water wash. A check for any existing underground utilities shall be conducted at the drilling location(s). Also, a brief"tailgate safety meeting" will be ' conducted to inform the well installation crew of anticipated hazards and the emergency action plan for the site. On-site workers will have Level D personal protection equipment available to them. All drilling, well construction, and sampling activities will be conducted using modified Level D personal protection as appropriate for the activities being conducted. An example of Level D personal protective equipment to be used at the site includes hard hat, safety glasses, steel-toed boots, earplugs, disposable rubber gloves, ' and disposable overalls. In the event that an injury occurs to any or all of the monitoring well installation team, emergency 911 service is available in the area, or they could be transported to the nearest hospital that provides emergency room services at Dameron Hospital, 420 W. Acacia Street, Stockton(209.461.3196). A map of the Dameron Hospital location is attached. Abandonment of MW-3 Physical abandonment of MW-3 will begin by removing the wellhead protection ' structure and bollards surrounding the well. Over-drilling the well will be accomplished using 8-inch nominal diameter hollow stem augers equipped with a guide bit. The guide bit will consist of an approximately 2"diameter protrusion extending from the cutting head of the augers which will act to keep the augers centered on the well pipe. The purpose of over-drilling is to remove the existing well materials from the ground (including the 2-inch diameter PVC well pipe, the annular grout seal, the bentonite seal, ' and the sandpack) to the total depth of the well(130 feet). Once the existing well material has been sufficiently removed from the subsurface, a tremie pipe will be inserted to the base of the augers, and a grout mixture will be pumped through the tremie pipe assesmbly. The grout mixture will consist of 5 to 10 gallons of potable water for each 94 lbs bag of Portland cement with up to 5%by weight of bentonite added to control shrinkage. As grout progressively fills the augers, the augers will be progressively ' removed from the boring. Prior to the last few augers being removed, a small excavation will be made surrounding the bore hole at the surface (approximate dimensions will be ' three feet deep and 20" diameter) and the final application of grout will fill the bottom 1 foot the excavation. No sooner than 24 hours after grouting is complete, the surface will be graded level using a clean backfill material. All waste material generated during over- drilling will be either disposed of off site at a landfill or used as fill material on site. June 21,2005 Page 2