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Lodi City Landfill November 16,2011 • North of Awani Drive,Lodi, California Project No. 104690061 Prior to constructing each LFG well, the bottom of each borehole will be filled with ap- proximately 1 foot of sand. The screened PVC casing will be placed into the HSA to center the well casing. Solid PVC casing will be used to construct the remaining sections of the wells that were not screened. After installation of each screened well casing, the filter pack, consisting of No. 3 sized Monterey sand, will be placed in the annulus between the well casing and the boring wall generally to approximately 0.5 feet above the top of the screened interval. The filter pack will be measured to monitor the depth and to avoid bridging between the well casing and the boring wall. Before placing the bentonite seal, the depth to the filter pack will be measured and additional sand will be added, as neces- sary. A bentonite seal will be placed in the annulus above the filter pack. The bentonite will be saturated and allowed to hydrate. The upper 0 to 2 feet of the LFG wells will be filled with concrete and a 2-foot diameter area of concrete will be constructed to surround the traffic-rated, flush-mounted well box or raised well monument. GPS coordinates of the • well will be recorded on the individual boring logs. Actual LFG well constructions will be based on field conditions. 11.4. Exploratory Trenches-Excavation Methodologies A California OSHA 40-hour trained operator will use appropriate equipment to excavate subsurface materials at each proposed trench location. In general, excavations will be to depths adequate to evaluate the depth of wastes and/or to the maximum depths that can be safely excavated with the equipment, and/or to depths adequate to confirm the absence of wastes, as applicable.Actual trench length, width, and depth will depend on site conditions, including depth and characteristics of the wastes. If wastes are observed in an exploratory trench, the excavation will continue until the base of the wastes are encountered (e.g., underlying formation (alluvial sediments) are encoun- tered), or to depths that do not endanger site health and safety and are obtainable with the on-site equipment, or depths that can be reasonably excavated based on the suspected loose nature of the fill/wastes, which may result in caving of the trenches during excavation. At • locations where wastes are not encountered, the trenches will be excavated to depths to 104690061 R 28 N1J7g1F&*UGre