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Ms. Natalia Subbotnikova, REHS October 24, 2023 Page 2 The proposed wells for installation within the Forward Unit are: single wells with perforations only within the waste mass and a drill-rig capable of drilling a large-diameter hole will advance an approximately 36-inch borehole through waste to the approximate depth listed in the well schedule presented on Sheet DS1 of the attached design drawings. Once the target depth is reached, a 6-inch standard dimension ratio (SDR)-11 high-density polyethylene (HDPE) well casing will be lowered into the boring. The pre-assembled pipe casing will have a row of four half-inch machine-drilled perforations spaced at 90-degrees horizontally around the pipe and the perforations will be spaced at 4-inches apart vertically between rows (see specifications for perforated pipe detail- hole spacing on Sheet DS2, Detail 3 of the design drawings). The HDPE well casing, including the bottom well caps, shall be joined by certified HDPE pipe fusion technicians using butt-fusion welding. For wells installed in areas of suspected higher temperatures, Schedule 80 chlorinated polyvinyl chloride (CPVC) may be utilized for the well casing in lieu of HDPE. During construction of each single completion, the well casing will be installed within the borehole, placed 1-foot above the bottom of the boring. Gravel shall be installed to at least two feet above the perforated portion of the second well casing. A Geonet with heat-bonded geotextile shall be installed above the gravel. A 2-foot clean, on-site soil plug shall be placed above the Geonet. A 2-foot bentonite layer shall be installed above the 2-foot soil plug. Soil will be installed above the bentonite layer to approximately 6 inches below the waste/soil interface. A bentonite layer will be installed above the soil layer and will be approximately two feet thick, extending at least six inches below the soil/waste interface. Soil will be installed above the bentonite layers to the ground surface. Within the soil layer, a 5-foot x 5-foot#3 rebar safety grate will be installed, at a minimum of 6-inches below ground surface, followed by a geomembrane boot, at a minimum of 1-foot below the ground surface. During installation of the materials,the well installer shall use a weighted measuring tape to verify proper placement of the materials. Each well will be fitted with a 2-inch wellhead that will be connected to an LFG lateral pipe, as detailed in the attached design drawings. The lateral pipe will be connected to the existing LFG conveyance header. The specifications included in the design drawings detail the proposed piping connections. PRE-CONSTRUCTION ACTIVITIES Permits through the San Joaquin County Environmental Health Department(SJCEHD) are required for the drilling of LFG extraction wells and well abandonments. All appropriate permits shall be obtained by either the driller or oversight contractor prior to beginning work. The Forward Landfill lies near the Stockton Municipal airport, and therefore, Federal Aviation Administration (FAA) clearance must be obtained prior to the start of drilling activities. All appropriate paperwork and notices shall be filed with the FAA and the Stockton Municipal airport prior to commencement of work. The duration of permitting through the FAA can take up to 45 days. PERMITTING SPECIFIC FOR PRESENCE OF ASBESTOS Due to the presence of asbestos containing materials (ACM) in the landfill, an Asbestos Disturbance 45-day Notification will be submitted to meet the requirements of 40 Code of Federal Regulations (CFR) 61.154. The notification will be submitted to the Environmental Protection Agency(EPA) and FORWARD 2023 LFG SJCEHD WORK PLAN