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4. Wetlands <br /> The National Wetlands Inventory aerial-based mapping indicates the presence of wetlands <br /> within the permit area. These wetlands are mostly associated with the vegetated banks along <br /> with South Platte River. BURNCO commits to conducting a wetlands survey prior to disturbing <br /> any potential wetlands. Exhibit C and F maps show the NWI mapped wetlands. <br /> 5. Aquifers <br /> The only identified aquifer located at the site is the shallow alluvial aquifer of the South Platte <br /> River. The depth to this aquifer varies throughout the year but is typically five feet below surface <br /> for the lower terrace (Pods 1 and 2) and 25 feet below the upper terrace (Pod 3). According to <br /> the U.S. Geological Survey's Ground Water Atlas of the United States', the underlying bedrock <br /> aquifer is the Laramie Fox Hills Aquifer of the Denver Basin system. The entirety of the Ewing <br /> Gravel Pit mining operation will take place in the overlaying alluvium above a shale/siltstone <br /> layer; the Laramie Fox Hills Aquifer will not be mined. <br /> 6. Surface Water <br /> The mining operation will impact surface water in the area through the stormwater runoff that <br /> enters the site. Map G-1 — Drainage Map show the drainage patterns and how they are affected <br /> throughout the life of the mine. The maps include information on the drainage basins currently, <br /> during mining, and post reclamation as well as the drainage directions throughout these stages. <br /> The primary concern for surface water protection at the site is preventing the discharge of <br /> sediment, oil, and/or hydraulic fluids from the operation areas. Oils and hydraulic fluids are <br /> stored on site following the standard best management practices. These practices include the <br /> use of secondary containment at fluid storage and transfer points, spill kits, and employee <br /> training regarding safe handling practices. Sediment is trapped onsite using controls and best <br /> management practices by directing and controlling surface water runoff that enters the disturbed <br /> areas. More information on sediment and surface water control is provided below. <br /> 6.1 . Surface Water Handling <br /> There are three drainage basins that collect all stormwater runoff on and around the Ewing site. <br /> These are shown on the Drainage Map. The first two consist of the lower terrace and cover <br /> Pods 1 and 2 respectively, as well as undisturbed portions to the south. Runoff from this <br /> drainage basin will be collected in the mining pods during mining and in the water reservoirs <br /> following reclamation. <br /> The second drainage basin exists on the upper terrace and consists of mining pod 3 and <br /> undisturbed upland to the south. Runoff from this drainage basin will be collected to the mining <br /> pod and processing area during mining and the water storage reservoir following reclamation. <br /> ' https://pubs.usgs.gov/ha/ha730/ch_c/ <br /> Ewing Gravel Pit <br /> August 2023 G-3 Lewicki&Associates <br />