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Transit Mix Concrete Co. <br /> EXHIBIT G <br /> WATER INFORMATION <br /> 1. Executive Summary <br /> Under C.R.S. § 34-32.5-116(4)(h), Transit Mix is required to minimize disturbances to the <br /> prevailing hydrologic balance of the affected land and of the surrounding area and to the quality <br /> and quantity of water in surface and groundwater systems. Transit Mix has designed the Hitch <br /> Rack Ranch Quarry (Quarry) to minimize impacts to the prevailing hydrologic balance of the <br /> affected land and surrounding area, including both the surface water and groundwater systems, <br /> as described in more detail below. Based on its planned mitigation measures, Transit Mix <br /> does not anticipate any impacts beyond a de minimis impact to the prevailing hydrology or <br /> quality and quantity of surface water and groundwater systems at the proposed site or <br /> surrounding area. <br /> First, with regard to surface water, there are approximately 5.9 square miles of watershed <br /> upstream from the Quarry area which will be unaffected. All mining will occur south of Little <br /> Turkey Creek. Therefore the watershed and the northern drainages will continue contributing <br /> water to Little Turkey Creek. Surface water flows from these upstream and northern areas will <br /> not be affected in any manner by Quarry development. No runoff waters will be captured and <br /> used by the Quarry operations. Rather, all water in the basin will be conveyed to downstream <br /> users consistent with Colorado water law. Runoff from disturbed areas will be temporarily <br /> detained in detention basins to remove sediment before the waters are discharged to Little <br /> Turkey Creek. The sediment basins have orifice plates to restrict outlet flows, thus assuring <br /> that peak flows in Little Turkey Creek will be maintained at rates similar to those which currently <br /> occur. A detailed discussion regarding the plans and procedures that will be used by Transit <br /> Mix to minimize disturbances to surface water quality and quantity is included below. <br /> Second, impacts to the groundwater system are likewise minimized by mine planning and <br /> operational procedures. Precipitation in the watershed area is the primary source of recharging <br /> the groundwater system, and the Quarry will have no effect on this source of recharge. <br /> Excavation will remain at least 10 feet above the level of the adjacent Little Turkey Creek, and <br /> thus, localized groundwater drawdown from Quarry development will remain above the creek <br /> elevation, and there will be no impacts to groundwater north of Little Turkey Creek. Intercepted <br /> groundwater south of the creek will cause drawdown of potentiometric levels in the fractured <br /> granite and diabase. The very low bulk hydraulic conductivity of the fractured rocks limits the <br /> extent of the drawdown to the Quarry area and a small area west of the Ranch property. <br /> An evaluation of potential drawdown impacts from the Quarrying operation is described in more <br /> detail in Exhibit G-2. This evaluation indicates that a drawdown of between 1 and 5 ft might <br /> Hitch Rack Ranch Quarry Permit Application <br /> March 9, 2018 G-2 <br />