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Green/Croissant, M-2001-022 <br />Imported Material and Related Activity <br />March 14, 2005 <br />Page 3 <br />(e) An Explanation of How the Backlilled Site Will Result in aPost-Mining <br />Configuration that is Compatible with the Approved Post-Mining Land Use. <br />The approved post-mining land use at Green/Croissant is wildlife habitat. One of the <br />primary objectives of the reclamation plan is to transform steeply sloped mining cells <br />into groundwater lakes and potential shallow wetlands suitable for wildlife habitat. The <br />availability of additional clean fill material will be of benefit to the post-mining land use <br />as it creates opportunities for shallow side-slopes and other land features consistent <br />with desirable wildlife habitat. <br />(f) A General Engineering Plan Stating How the Material Will be Placed and <br />Stabilized in a Manner to Avoid Unacceptable Settling and Voids. <br />Engineering considerations related to the current reclamation plan are discussed in"the --- <br />approved 112 reclamation permit. These considerations continue to be applicable since <br />this plan does not modify the existing reclamation plan. <br />Finally, we note two ancillary considerations stemming from this backfilling plan: <br />1. To create additional surge capacity in stockpiles and facilitate truck movements, <br />the operator has expressed a desire to make minor adjustments to the location of <br />the screening berm at the perimeter of the processing area. The berm and <br />stockpiles were both noted on Exhibit C-3 of the M-2001-022 application, and we <br />believe the conceptual layout of the features on this Exhibit would not be <br />materially affected by the proposed adjustments. Stockpiles and plant layout will <br />adhere to the general plan approved in the 112 permit, and berms will continue to <br />function as screening and as stabilized topsoil stockpiles during active mining. <br />2. The Operator's plan is to fill Cell 2 in a manner that raises grades across the final <br />profile, shifting shallow areas to the east and possibly reducing open water areas <br />by using more of the groundwater lake for potential wetlands or shallow water. <br />Given the potential for a significant amount of new backfill material, we have <br />specifically reexamined the Reclamation Plan to see if it will accommodate, <br />without adjusting the extent of any permitted Reclamation Plan features, a <br />maximum scenario of 320,000 cubic yards of additional backfill. Based on <br />computer modeling with extremely conservative assumptions, we believe that <br />groundwater lakes with 4 to 5 percent shoreline slopes -not atypical of natural <br />groundwater lakes -would accommodate the additional fill. The Operator's plan <br />is consistent with this scenario, with additional fill contributing to shallower <br />shoreline slopes more evocative of natural groundwater lakes. <br />Regarding Cell 2, the Reclamation Plan notes that, in conjunction with Cell 1, <br />Cell 2 will be partly backfilled to "near-grade (ready for topsoil)" and other areas <br />will be mined "to 3:1 or shallower slopes." Also of note, the DMG has specifically <br />held that wetland mitigation may not be pertormed at the site without a technical <br />