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Taj Bahadori Page 4of8 August 30, 2018 RWQCB's Monitoring Well Installation Report Guidelines. The report will be signed by a California -licensed professional engineer or geologist. The first monitoring event for this well will included the full suite of Constituents of Concern from Table VI of the FSL's Monitoring and Reporting Program Number R5-2015-0058. Revised Scope—Install Monitoring Well MW -7 near SG -6A In order to maintain a compliant monitoring system per the WDRs and Title 27, Section 20415 and 20420, APTIM understands that the County will install a new monitoring well, MW -7, southeast of Module I near SG -6A (see Figure 1). This well will be used to provide control of groundwater flow and direction across the site and to determine if groundwater is being affected southeast of the unlined Module I. Well Location - The location of the new well MW -7 will be approximately 20 feet from the existing landfill gas monitoring probe SG -6A, refer to Figure 1 for approximate location. 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 ground surface in proximity to SG -6A is approximately 262 ft. mean sea level. Based on the second quarter 2018 groundwater contour map provided in the First Semiannual 2018 Monitoring Report, groundwater elevation in proximity to SG -6A is approximately 38 ft. mean sea level with an anticipated depth to groundwater of 224 ft. bgs. The proposed initial exploration depth of drilling at the new well MW -7 is 244 ft. bgs. MW - 7 bore hole will be advanced using the sonic drilling method. The intent of initially exploring to a depth of 244 ft. bgs is to determine the depth of first encountered groundwater (i.e., the water table) at the MW -7 location. The actual depth of the completed well will be based on encountering at least 15 ft. of water in MW -7. The actual depth of MW -7 will be determined in the field and the borehole will be extended 15 feet below the encountered water table. Well Installation Schedule — MW -7 will be installed during the fourth quarter of 2018. The drilling and installation of the well may take five (5) or more working days due to its considerable depth. Well Installation — MW -7 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 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 083018 FH-RWQCB-Revised Work Plan_Final.docx