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EXHIBIT G WATER INFORMATION <br /> 1 . General <br /> The Ewing Gravel Pit is within the floodplain and floodway of the South Platte River. The <br /> Platteville Ditch traverses the site from south to north roughly halfway across it. Mining pods 1 <br /> and 2 are located on the lower, western terrace which is within the floodplain. Mining pod 3 is <br /> located on the upper, eastern terrace along US-85, outside of the floodplain. Mining within the <br /> floodway/floodplain will be conducted with no filling or stockpiling above the natural ground <br /> grade. Groundwater is located roughly five feet below the natural grade in mining pods 1 and 2; <br /> 25-feet below grade in mining pod 3. All groundwater onsite is part of the South Platte River <br /> alluvial aquifer. Prior to mining any pod a slurry wall will be installed around the perimeter of <br /> each terrace of gravel, as shown on Map C-2. These slurry walls will be for the development of <br /> water storage reservoirs following reclamation. <br /> Xcel Energy maintains a system of groundwater wells on the property for the purpose of <br /> supplying water to their power plant to the east, in Keensburg. These wells will be protected <br /> from groundwater impacts by their proximity to the South Platte River. Analysis conducted by <br /> BURNCO and shown in Appendix G-3 demonstrates this protection. <br /> BURNCO is committed to protecting the hydrological balance and water quality at the site. <br /> 2. Water Quality Protection <br /> The primary concerns surrounding water quality protection at the Ewing Gravel Pit site are the <br /> potential impacts to the surface and groundwater from sediment, hydraulic fluids, and diesel <br /> fuel. Sediment will be controlled through the use of stormwater retention within the disturbance <br /> area through the life of the mine. The site will be graded in a manner that maintains all surficial <br /> flows within the disturbed area, in turn containing all sediment and unwanted discharges from <br /> leaving the site. Hydraulic fluids and diesel fuels will be contained within vehicles or with <br /> adequate storage methods that follow best practices of maintenance; these practices including <br /> regular inspections of vehicles, hydraulic lines, and any other potential spill sources. Diesel fuel <br /> will be stored on-site in double walled tanks with secondary containment. Fuel storage will be <br /> stored away from exposed groundwater and other waterways. Spill kits will be located near all <br /> fueling areas to clean up inadvertent spills as soon as possible. An SPCC plan will be in place <br /> to prevent oil discharges and establish a response procedure in the event of spills. <br /> Any surface water discharges from the site will be sampled in accordance with the NPDES <br /> discharge permit. All discharge will be via the approved Outfall, the proposed location of which <br /> is shown on Map C-2. <br /> Ewing Gravel Pit <br /> August 2023 G-1 Lewicki&Associates <br />