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Kennedy Jenks casing to provide at least 2 inches of annular space between the well casing and borehole wall. Continuous core will be collected for lithologic determination. The soil produced during the drilling will be logged under the supervision of a professional geologist or engineer, in accordance with the SOG for Borehole Logging (Appendix C). The total depth will be approximately 20 feet below first-encountered water, or saturated aquifer. Based upon the Site conditions, first water may be encountered between 60 and 70 feet bgs so the borings' total depths will likely range from 80 to 90 feet bgs. 2.2.2.2 Well Construction The boreholes will be converted into completed groundwater monitoring wells installed by a licensed drilling contractor in accordance with the Kennedy Jenks' SOG for Well Construction and Development (Appendix D). The proposed monitoring well design will be similar in design to the existing monitoring wells. The monitoring wells will be constructed with 4-inch diameter Schedule 40 polyvinyl chloride (PVC) casing. For the screened interval, 0.010-inch slots or other 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 4-inch diameter, Schedule 40 PVC blank casing. 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 sized accordingly for the well screen slot size selected (Cemex#2/12 or equivalent for 0.010-inch slots). The filter pack will extend upwards from the bottom of the boring to 1 to 2 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 to minimize downward migration of the grout seal into the filter pack. A cement/bentonite grout will be placed so as to extend continuously from the top of the bentonite pellet layer to less than 1 foot below grade. It is anticipated that this grout seal will be extended to an approximate depth of 35 feet bgs. In accordance with local regulations, a San Joaquin County representative will be onsite to observe 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 zones will be completed above grade and furnished with a protective, locking steel casing. Wells located in paved or trafficked areas will be completed with a traffic-rated monument. Each well will be completed 1 to 2 inches above grade and furnished with a sloping concrete apron to facilitate surface drainage away from the well. A schematic diagram of well construction details is shown on Figure 3. After waiting a minimum of 48 hours to allow curing of the grout and concrete, the monitoring wells will be developed by surging and pumping until the water removed from the wells is sediment-free or until no further improvement in water quality is observed. The wells will be allowed to recover for a minimum of 72 hours following well development, prior to monitoring and sampling. The locations and well casing elevations of these new monitoring wells will be horizontally and vertically surveyed by a licensed land surveyor. The ground surface and top of well casing elevation will be surveyed to the nearest 0.01 foot relative to mean sea level. The ground surface and casing will be surveyed to the National Geodetic Vertical Datum (NGVD 1983), Monitoring Well Installation Work Plan, The Wine Group, Franzia Winery, Ripon, California Page 5 \\kjc.local\kjc-root\kj-offcelsfolprojects\is-proj1202612665002.00_twg ripon gw men well supportM-reportshwispltwg ripon men well install wp_020426.docx