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Kennedy-Jenks Consultants • Survey the proposed boring locations for potential location conflicts with subsurface utilities by performing a utility clearance check prior to drilling. The survey will be performed by contacting Underground Service Alert (USA) for utility clearance at least two working days before the scheduled fieldwork commences. • Contract with a California licensed (C-57) drilling contractor to perform field work. • Select a state-certified laboratory to conduct laboratory analytical services. 2.2.2 Installation and Development of Monitoring Wells Following completion of the pre-field activities, a licensed drilling subcontractor will advance the subsurface borings and install the monitoring wells at the selected locations. The soil b ings e7will be drilled using a truck-mounted drill rig equipped with 8-inch hollow stem auger or equipped with an air-rotary system capable of drilling an 8-inch diameter borehole. The orings will be advanced approximately 10 to 15 feet into the groundwater, or reasonable depth to identify the thickness of the water bearing zone. Soil samples for logging and soil characterization will be collected continuously using a split spoon sampler or four-foot core barrel, if available. The soil cuttings will be lithologically logged using the USCS (ASTM D-2488-93) system under the direction of a California Professional Geologist who has expertise in lithologic logging. Field documentation will include the completion of boring logs that record the soil encountered during drilling of each borehole, soil sampling intervals, depth and thickness of the saturated zones, and well construction details. Following completion of the wells, well construction logs will be prepared. General procedures for sampling and logging are presented in Kennedy/Jenks' Standard Operating Guideline— Borehole Logging (Appendix A). The monitoring wells will be constructed with 2-inch diameter Schedule 40 polyvin ? chloride(PVC) flush-threaded casing. For the screened interval, 0.010-inch slots(gpiother appropriate slot size for the lithologies encountered will be selected based upon the lithologic logs from the soil borings. The remainder of each well above the screened section will consist of flush-threaded, 2-inch diameter, Schedule 40 PVC blank casing. The wells will typically have 20-foot screened sections, however, the screened interval may be modified in response to observed subsurface conditions. A continuous filter pack will be placed in the annular space between the screened section and the wall of the boring. The filter pack will consist of washed, packaged sand that is sized accordingly for the well screen slot size selected (#2/12 or equivalent for 0.010-inch slots). The filter pack will extend upwards from the bottom of the boring to one to two feet above the screened section. All wells will be pre-developed after the filter pack is installed, and prior to the bentonite seal being installed. A 2-to 5-foot layer of protective bentonite clay pellets will be placed above the filter pack to minimize downward o/ migration of the grout seal into the filter pack. A cement/�tonite r4_out will be placed so as to ° extend continuously from the top of the bentonite pellet layer to less than one foot below grade. In accordance with local regulations, a San Joaquin County representative will be onsite to observe or approve of the grouting. A locking expansion cap and well-housing enclosure will be installed to control access to the well opening. Wells located in unpaved areas near the land application areas will be completed abovegrade and furnished with a protective, locking steel casing. Wells located in paved or trafficked areas will be completed approximately at grade and Page 4 Preliminary Work Plan for Evaluation of Nitrogen in Groundwater Musco Family Olive Company, Tracy, California p:Yeprwq�etlmin4obbT0201UG.�murnoMeNA+epwlaNiPagen vrF phVexLEx