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The proposed mining operation will consist of conventional wet or dry mining (without a slurry wall) of surficial sand and gravel. Mining will include the following elements, some of which (e.g., plant azea setup azui dewatering trench excavation for Phase One) will occur concurrently: • Fencing improvements • Topsoil stripping and stockpiling • Plant area and roadway layout and construction • Perimeter dewatering trench excavation • Excavation/transfer of pit-run material to field hoppers • Conveying and processing • Concrete and asphalt hatching • Product hauling • Reciamation grading and planting • Slurry wall construction (optional) ]nitial work will consist of improvements (if necessary) to perimeter 4-strand barbed wire fencing, erettion of six foot chain link fencing around some or all of the plant areas, topsoil stripping and stockpiling, plant construction, and Phase One area dewatering trench excavation. Topsoil berms will be concentrated along County Road 20.5 and along the southern end of the eastern site boundary to minimize the visual impacts of the operation. Dewatering trench excavation will be performed with an excavator down [o the top of or up to several feet into the underlying clay shale bedrock. Trench sidewalls N bedrock will be excavated approximately vertical, The wenches will be constructed to develop flow to discharge locations and minimize evaporative losses. Ground water will drain from the alluvial sand and gravel, collect in the trenches and be discharged to Boulder Creek under an NPDES discharge permit as shown on Figure D-1. Dewatering trench flow will provide the source water for processing. Additional information related to dry mining via dewatering trenches is included in Exhibit G -Water Information (Chapter VIII). Mining excavation will be performed by loaders and/or scrapers at temporary excavation slopes of 1:1 (H:V). As mining progresses from the southeast towards the west and north, field conveyors, 10 K~A