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Taj Bahadod Page 3 of 6 July 6, 2018 the purpose of reassessment of calculation concentration limits for the down -gradient wells in the DMP. Well Location - The location of the replacement well MW -4A will be approximately 15 feet from the existing well MW -4. The exact location will be determined in the field, based on a suitable location that is relatively level for the drill rig to set up on. The well location will be surveyed after installation. Exploration - The total depth of existing well MW -4 is 298 feet (ft.). The proposed initial exploration depth of drilling at replacement well MW -4A is 320 ft. MW -4A bore hole will be advanced using the sonic drilling method. The intent of initially exploring to a depth of 320 ft is to determine the depth of first encountered groundwater (i.e., the water table) at the MW -4A location. The actual depth of the completed well will be based on encountering at least 15 ft. of water in MW -4A. The actual depth of MW -4A will be determined in the field. If the water table is encountered at a depth of 307 ft., the bore hole will be extended to a depth of 322 ft. If the water table is encountered at a depth of 302 ft., the bottom of the well will be set at 317 ft. Well Installation Schedule MW -4A will be installed during the third 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 casing will be 2 -inch diameter schedule 80, flush -threaded polyvinylchloride (PVC). The well screen will be 20 ft in length; 2 -inch diameter PVC schedule 80, flush - threaded with 0.02 inch factory cut slots. 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, consisting 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: 2018-07-16 FH Workplan