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Work Plan to Install Compliance Groundwater Monitoring Wells,Musco Family Olive Company Tracy California mobilization to the field. A private utility locator will also be contracted to identify underground utilities at each monitoring well location. In addition,the applicable county permits required for the work will be obtained. ' Compliance Groundwater Monitoring Well Installation Well installation activities are anticipated to take place in late November 2013. Based on the installation ' procedures used for existing groundwater monitoring wells at the Musco facility, it is expected that the compliance groundwater monitoring wells will be installed using hollow stem auger(HSA)technology or mud rotary technology under the supervision of a California Professional Geologist.The HSA drill rig will ' have the ability to be retrofitted into a mud rotary drill rig if the subsurface conditions require the change in technology. The HSA method consists of a drill rig that rotates tubular steel augers (4.25-inch inner diameter,8-inch outer diameter) into the subsurface.The augers have a hollow axis with steel flights spirally welded on the outside.A hollow drill bit is attached to the first HSA that is advanced into the ground.The ' sediments encountered on the outer edges of the bit and lead auger are cut and conveyed to the ground surface via the outer flights of the auger. ' This drilling method allows soil sampling and completion of the monitoring well to be conducted inside the hollow augers while the augers allow the boring to remain open. Due to the anticipated depth of ' these wells,soil sampling will be completed every 5 feet using a split spoon sampler,as technically feasible.The soil samples will be used to describe the lithology and to identify water bearing zones.The soil sample will be examined and the lithology will be logged by a field geologist using the Unified Soil ' Classification System (USCS).The lithology will be recorded onto the soil boring/monitoring well construction logs (Attachment 1). The soil boring logs/monitoring well construction logs will be prepared under the direction of a California Professional Geologist. If the formation requires, mud-rotary drilling technology will be used to get to the target depth.The mud-rotary drilling method consists of a truck-mounted drill rig that rotates a bit (tri-cone or drag bit)at ' the end of hollow drill rods. Drilling mud (a thick mixture of water and bentonite) is pumped from a trough at the surface, down to the drill bit through the center of the drill rods,and back up to the surface between the drill rods and the inside of the borehole.The sediments cut by the rotating drill bit ' are carried up to the surface by the drilling mud,where they are screened and/or shoveled out.The "screened" drilling mud then runs back into the trough at the surface where it is recirculated back down the drill rods in a continuous system.The borehole opened by the drill bit is kept stable by hydrostatic pressure imposed by the heavy drilling mud,which is in constant circulation during drilling. ' Previous investigations indicate that first encountered groundwater may be present between 150 feet below ground surface (bgs)to 200 feet bgs,or might not be encountered at all.The target depth for the compliance groundwater wells is anticipated to be approximately 200 feet bgs.Wells will not be installed deeper than 200 feet bgs.The drill bit will be advanced to first encountered groundwater and the screen interval will span the entire length of the water bearing zone,or a maximum screen length of 20 feet.After the desired depth of the boreholes is reached,the augers will then be slowly removed ' from the borehole as the monitoring well casing, sand, bentonite,and/or grout are added from the Terraphase Engineering Inc. Page 3 of 6