PERMFILE117598 - Laserfiche WebLink

Home Browse Search

EXHIBIT D -MINING PLAN This section follows the requirements outlined in Section 6.4.4. (a) Description of the methods of mining to be employed in each stage of the operation as related to any surface disturbance on affected lands The applicant will begin mining the western portion of the site and proceed east through the site in phases to minimize the amount of land disturbed at any one time. Phases will range from 11 acres to 32 acres. Only one phase or portions of two phases and the processing area will be disturbed by mining during any phase of mining. Lazge portions of [he site will be reclaimed years before the last phase is mined. Please refer to the Mining Plan Map for details on the phasing order. Site Preparation Initial disturbance of the property will include preparation for the first processing site. This processing area is located outside of the 100-year floodplain. Undisturbed areas will be cultivated agricultural fields or pasture until mining commences. In addition, as part of Hall- Irwin's effort to enhance the wildlife habitat in the Big Thompson riparian corridor, Hall- Irwin will create approximately 2.2 acres of wetlands in the initial phases of the mining operation by lowering the ground elevation to within 18" of groundwater. Then this area will be seeded with the wetland seed mix provided in Exhibit E, Table 3. ' Proposed Mining Process for Each Section Before mining commences in phase 1, Hall-Irwin will install a dewatering trench around the mining area. For phases 2 through 5, Hall-Irwin will first install a slurry wall around the phase and then dewater it. This water will either be pumped into a settling pond and ultimately discharged into the Big Thompson River or it will sheet flow into the Big Thompson riparian cottonwood gallery to help preserve the existing vegetation and help establish new vegetation. After the pod is dewatered, scrapers will strip the topsoil and stockpile it. Next they will strip the overburden. When the alluvium is sufficientlydry, afront-end loader will place the gravel in haul trucks or on conveyors, which will transport the material to the processing area. Overburden from phase one will be used to fill portions of the Town of Milliken's property adjacent to the mining site. In the subsequent phases overburden will be used to reclaim the shoreline of the previous phase. As the azea is mined, overburden will be placed along the edges to create the shoreline of the future lake. Topsoil will be placed on finished slopes and the area will be seeded. Plantings around the reclaimed pods will be installed after mining at the site is complete. If portions of the site will not be disturbed again by mining operations, plantings in these areas may be installed sooner. Processing Imported Material Hall-Irwin may process materials imported from other sites. Hall-Irwin Corporation Bernhard[ Resource Page l2 of 41 MLRB 112 Permit Application