2007-09-11_REVISION - M1997054 (2)

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reservoir perimeter to achieve the final grade. Upon placing the backfill material, 95 percent compaction will be required for integrity of the slope and liner. Final reclamation by capping with topsoil and revegetating the entire slope will follow backfilling operations closely to minimize the amount of disturbance at any one time. Inlet and outlet facilities for future use of the reservoir, as well as the spillway, have not been designed at this time. Once an end user is identified, design of these facilities could be implemented during the reclamation phase. The installation of these structures is not required to restore the land to a beneficial use. Rip rap may be required or recommended along the reservoir embanlanent toe for additional stability during critical rapid drawdown operations of the future reservoir. Rip rap along the dam crest may also be necessary for wave erosion. Any necessary rip rap will likely be available on site from existing boulders within the sand and gravel area, or from the granite quarry. The approximately 15-ft high dam in the southeast corner would result in a jurisdictional dam. The jurisdictional dam would likely be considered a High Hazard dam by the SEO and will undergo permitting through the Colorado SEO office. Adam is considered jurisdictional if it meets any of the following criteria: ^ The normal high water surface is a vertical height of over 10 feet from the elevation of the lowest point of the natural surface of the ground along the centerline of the dam. ^ The dam has a capacity of over 100 acre-feet. • The surface area exceeds 20 acres at the high water line. Preliminary plans and specifications are being prepared and will be used for submittal to the SEO. This portion of the reservoir structure would not be constructed until it was approved by the SEO. Reclamation Measures/Materials Handling Backfilling will be done to provide stabilized shorelines around the reservoir and to minimize erosion. As previously mentioned, the backfill material will consist of bedrock claystone and shale, granite crusher fines, and topsoil. There will be no known toxic or hazardous materials in the backfill materials. Additionally, it is not likely that acid forming or toxic materials will be encountered during mining. The mining will not leave high walls on the property. In addition, there will be no auger holes, excavations, or shafts left on the property. Top Soiling Soil will be salvaged and stockpiled as detailed in the previous reclamation plan. By using concurrent reclamation techniques, the topsoil is not expected to remain in stockpiles for more than 2-4 years. The stockpiles remaining for more than one growing season have been seeded with afast-growing vegetative cover to prevent erosion. All topsoil has been retained on-site to reclaim the reservoir slopes, and other areas disturbed by mining activities. Where required and available, topsoil will be replaced to a depth of approximately 4-6 inches. No topsoil will be exported from the site. There is not an abundant supply of topsoil in this azea. Reclamation decisions will be made on the most beneficial areas to apply the stockpiles that are available. Range Aggregates, LLC- Par/ulale Quarry DMG !!2 Permit Amendment Page 20