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Ms.Natalia Subbotnikova,REHS Geosyntec° May 5, 2026 consultants Page 2 11 construction details including total depth and screened intervals. The DPT borings will be destroyed in accordance with San Joaquin County standards with neat cement grout. SV�41 INSTALLATION RATIONALE The 2026 GCCS improvement and expansion includes the installation extraction well SVE-11. The well is designed to control and minimize LFG surface emissions and migration. SVE-11 extraction well will be installed at the perimeter of the landfill outside of the waste limit to mitigate LFG migration in the vicinity of GP-10 (see Attachment A). The proposed SVE well will be connected to a header pipe via a lateral lateral pipe to route the collected LFG to the existing flare station and/or to the LFGTE Plant. SVE-11 CONSTRUCTION DETAILS The',total boring depth of the planned SVE well is n 37 ft bgs,which will be advanced using a 12" diameter hollow stem auger. SVE-11 will be constructed using 4-inch-diameter Schedule 80 (SC"80) polyvinyl chloride (PVC) solid and slotted pipe casing. The slotted pipe section will extend from 18 to 36 ft bgs. The'pipe casings will be capped at the bottom with SCH80 PVC cap, glued and secured with 3 lag screws. The well casing will be placed at the center of the wellbore and suspended so the bottom of the casing is approximately 1 foot above the bottom of the wellbore. The annulus around the perforated well casing will be backfilled with a gravel pack as shown in the drawings. A geocomposite donut will be installed above the gravel, followed by a layer of 1 ft of soil 13 ft- thick bentonite plug. The bentonite plug will be formed by evenly distributing 6-inch lifts of granulated bentonite or bentonite chips between the well casing and the walls of the borehole. The bentonite will be thoroughly mixed and hydrated in accordance with manufacturer recommendations before placement. The bentonite plug will be allowed to cure for at least 20 minutes.The bentonite plug will extend from 1 to 13 ft bgs,and a neat cement grout will be placed fro Im 0 to 1 ft bgs. Fol owing placement of the cement grout, a 5-foot by 5-foot safety grate will be installed, an additional 1 ft of soil will be placed above the safety grate, and above the grate, a 20 ft by 20 ft geomembrane wellbore seal will be installed. Details are shown in Sheet 5 of Attachment A. The SVE well will be fitted with a 2-inch QED style wellhead that will be connected to an LFG lateral pipe, as shown in the drawings. The lateral pipe will be tied-into an existing LFG header pipe as shown in the drawings (Sheet 3). Forward DPT Investigation and SVE-1 I Installation Work Plan