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<br />EXHIBIT G -WATER INFORMATION <br />The reclamation plan for the site will be four water storage reservoirs; two in the original permit <br />azea and two in the new area being added by this amendment. The reservoirs will be created by <br />placing a compacted overburden/clay liner along the shorelines of the excavated pits (see Exhibit <br />F -Reclamation Plan Map). Placement of the compacted liner along the shoreline will eliminate <br />groundwater inflow into the pits. The pits will be mined down to bedrock and therefore there <br />will be no infiltration of water through the bottom of the pits. These reservoirs are exempt from <br />the regul;itions of Senate Bill 120. <br />The original permit entails the creation of two groundwater lakes with a total of 78.6 surface <br />acres. The only change to the reclamation plan for the existing permit area is the creation of <br />water storage reservoirs by lining the pit slopes rather than groundwater lakes. The total water <br />surface of the two reservoirs in the original permit area will be 78.6 acres. The two reservoirs <br />in the amendment area will have water surface azeas of 22.72 acres and 11.59 acres for a total <br />water surface area of 34.31 acres. <br />Approximately the northern half of the amendment area is within the St. Vrain Creek 100 year <br />floodplain as shown by the FEMA map (see attached floodplain map -Exhibit G-2). The topsoil <br />and overburden stockpiles will be located outside of the floodplain boundary as much as possible. <br />Any stockpiles within the floodplain limits will be aligned with the general direction of flow, to <br />limit obst~vction of the floodplain and limit potential for erosion. There will be no stockpiling <br />done within the floodway. All work within the floodplain will conform to Weld County Flood <br />Hazard Rc;gulations. <br />Due to the removal of material from the site the net floodplain cross sectional area will increase <br />and therefore provide more flood storage than what currently exists. <br />Water Use <br />Water use at the site will include evaporation from exposed groundwater, water retained in the <br />material removed from the site, and water used for dust control of haul roads and stockpiles. <br />Mining in the amendment area will intercept the water table. In order to enable dry mining of <br />the amendment site, dewatering trenches will be constructed around the perimeter of the pit and <br />water will be pumped to St. Vrain Creek. Therefore, there will be no evaporation from the pit <br />during mining. The only evaporation from the site will include water pumped from the pit to <br />settling ponds which will be used for the washing operation. Approximately 2.1 acres of water <br />is exposed in the wash ponds. <br />The annual evaporation is 39 inches at the subject location. The precipitation at the mine site <br />is estimated to be the same as that found at the nearest weather station which is located in <br />Longmont. The annual mean precipitation is 13.00 inches/year. <br />7 <br />