2018-09-25_REVISION - M2014043 - Laserfiche WebLink

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Albert Frei and Sons, Inc. September 24, 2018 Hatchery Pit - Technical Revision 01 deep well in their compound south of the mined area . Neither well is up gradient from Stage 2 and their tops are lower then the elevation of the shale under Stage 2 . These wells will not be impacted by dewatering in Stage 2 . Reclamation Plan Pre-1981 Lake Area During site preparations the pre-1981 northwest lake was dewatered and gravel left from the original mining operation was salvaged from the bottom. At that time it was determined that the underwater volume of this area was sufficient to hold the wash tailings from the processing operations, leaving Stage 1 as inert fill area . The Army Corp' s of Engineers determined the lake is not Waters of the US, so backfilling is allowed. A dike made of shale from the lake bottom was built to divide the lake into a freshwater source on the west side and a silt pond on the east . The eastern part of the pre-1981 lake, silt pond area, will be filled to the original ground elevation around the lake or approximately 50681 . The filled area, dike and lake perimeter will be reclaimed using the approved methods shown on Map Exhibits E-1 thru E-3 or Map Exhibit F . The area backfilled may be used as Industrial area as shown on Option 2 so it would be graded and graveled. The lake slopes would be resoiled and seeded. If the silted in area will be reclaimed it will be done following the approved resoiling and seeding plans . The western portion of the lake will remain as lake area. In the lake areas the south, west and north underwater shores were not disturbed so do not need reclamation and the west side of the dike was graded 3h to lv before the lake was allowed to refill . Map Exhibit C-1 Mining Plan Map has been revised to show the current conditions in the northwest lake area and the proposed location of the compacted liner and french drain in Stage 2 . 3