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Exhibit G CMLRB 112 Permit Application Agile Stone Systems. Inc. • was requested by the Division of Minerals and Geology. After several discussions with the Division of Minerals and Geology, it was agreed that crossings designed for 10 year storm events would be suitable. Each crossing would have a cleaz span to avoid any sediment impact on normally flowing water and to have no equipment contact normally flowing water. During major storms, the crossings would not be used by the applicant. The 10 year event requires 312 square feet to allow passage such a storm event. Water would flow at 847 cfs. Each crossing would also have rip rap rock on both sides and both ends of each crossing to further guard against erosion. Larger storm events will also be readily handled by the crossings but some of the water may flow over the crossing structure. The two Tallahassee Creek crossings are subject to Army Corps of Engineers regulations who have reviewed the designs for both crossings. Any impact from water discharge from the mining azeas into the Tallahassee Creek will be subject to the provisions of Sand & Gravel Process and Stotm water Discharge General Permit Number COG- 500325 issued by Colorado Department of Environmental Health, Water Quality Control Division August 25, 1997. The 100 year flood plain boundaries were calculated from the same data base. Cross sections were developed for various locations along the Tallahassee Creek based on the profile of each specific cross section site. The end points of the cross section were connected to identify a likely 100 year flood plain. Each cross section and the location of • each cross section aze shown in maps enclosed. Similar analyses were completed for the drainage azeas for both the granite and sandstone quarry areas. Each watershed azea was considerably smaller than the Tallahassee watershed area as can be seen in the next table. Each pond and emergency outflow system will handle the 100 year storm events. The granite pond was designed to retain nearly 10 acre feet of sediment while the sandstone pond was designed to retain neazly 2 acre feet of sediment. Using 100 lb/cubic foot and an estimated 1 tn/acre/yr, the granite pond would have a theoretical life of 74 yeazs and the sandstone quarry pond would have a life of 210 years. Sediment will be removed from each pond more frequently as needed. A copy of the complete Tallahassee watershed basin project is enclosed in the Supplementary Data. The drainage basin and sub-basin maps and crossing designs are repeated here. The 100 yeaz stone event cross sections and sandstone/quarry basin azeas and drainage systems maps are also displayed here. • 6