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Taj Bahadori Page 3 of 8 August 30, 2018 Well Installation Schedule —MW -4A will be installed during the fourth quarter of 2018. The drilling and installation of the well may take six (6) or more working days due to its considerable depth. Well Installation — MW -4A will be drilled and developed by a licensed C-57 Contractor. The bore hole will be logged following visual -manual methods described in ASTM D2488 and under the supervision of a California -registered professional geologist or civil engineer. Drilling spoils will be stockpiled near the boring and dispersed near the vicinity of the boring after well installation. The well detail is provided in Figure 2. The well casing will be 2.5 -inch diameter schedule 80, flush -threaded polyvinylchloride (PVC). The well screen will be 20 ft. in length; 2.5 -inch diameter PVC schedule 80, flush -threaded with 0.02 -inch factory cut slots. The upper 10 feet of the well casing will be reduced to 2 -inch diameter PVC. Centralizers will be used to center the well casing in the bore hole and will be composed of plastic or stainless steel. The sand pack will be #2/12 size, placed in the annulus between the well screen and the boring, and brought to at least two feet above the top of the well screen. A bentonite seal will consist of sodium montmorillonite clay. The bentonite seal will be at least two feet in vertical thickness and will be placed above the sand pack prior to grouting the remaining well annulus. The neat cement well seal will be placed above the bentonite seal, and will consist of Portland Type II cement and having a bentonite mixture of 5 percent by weight. Because of the considerable depth of the well, the cement seal will be placed in at least two lifts. Well Development - The drilling contractor will allow a minimum 48 hours for the neat cement seal to set. The contractor will develop the well within 7 days of completion of the well. The contractor will develop the well using mechanical surging or over pumping, or a combination thereof. Development of the well will continue until: • Well water is clear to the unaided eye • Sediment in the well casing is less than 0.1 foot thick • Water removed during surging and purging will be a minimum of three times the water volume in the well prior to the start of purging plus three times the volume of water added (if any needed) for purging and surging • Temperature is consistent within 0.2 degrees Celsius • Specific conductivity is within 10 percent change • pH varies less than 0.2 pH units • Turbidity varies not more than 10% Well Installation Report - A well installation report for well MW -4A, including the analytical results of first monitoring event, will be included with the Second Semiannual and Annual 2018 Monitoring Report. Boring log, well completion details, and survey data will be uploaded to GeoTracker. The well installation report will include the items listed in the 083018 FH-RWQCB-Revised Work Plan_Final.docx