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i ~ lize the tailings. This liming agent will be mixed to a depth of about 20 inches by additional ripping, which will reduce compaction and help to control erosion through contour tillage. After ripping, the three eloping sides of the tailings emb3r,k.,,Pnt will be covered by a 3 to 4 inch layer of the stockpiled topsoil. 'Thin topsoil will add organic matter and improve .the filth and fertility of the sterile mill tailings. Additional lime and fertilizers will be incorporated into the topsoil by raking and harrowing to a depth of about 6 inches, which will produce a uniform seedbed. The liming agent will be applied at a rate of 5 additional tone per acre, while nitrogen, phosphorus, and potassium will probably be applied at a rate of between 400 and 500 pounds per acre during this final preparatory work. A seed mixture containing both native grasses and intro- duced species will then be planted at the rate of around 40 pounds per acre by hydroeeeding, or by employing a Brillion grass seeder. F4nally, a wood fiber mulch will be spread over the embankment to control wind and water erosion and to assist in retaining moisture during grass seed germination. The third phase of the reclamation plan for the tailings impoundment area that will be implemented is the re vegetation of the tailings pond. Since the tailings pond will be the last part of the tailings retention structure to consolidate, the re vegetation of this area will begin at a later date than the three eloping aides of the starter dike and the tailings embankment. During thin period of tailings consolidation, a wood fiber mulch will be applied to the dried areas on the top of the tailings retention structure to prevent water erosion and to control duet. The re vegetation of the tailings pond will be started as soon as the tailings can support the weight of a conventional tractor. 'This will probably be within the first two years of the cessation of tailings deposition. Once the former tailings pond area has physically stabilized, the surface will be leveled by grading it with a small tractor. Then, the graded surface will be ripped and a liming agent spread over the area at the rate of 15 tons per acre to neutralize the mill tail- ings. 'This liming agent will be mixed to a depth of approximately 20 inches by additional ripping, which will reduce compaction and improve water retention. A 3 or 4 inch layer of organic fertilizer will be applied to this ripped surface to supply nutrients and increase moisture retention capability. This application of fertilizer will also add organic matter to the mill tailings and help to prevent solarization. Because the organic fertilizer will be darker in color than the tailings, it will provide protection from the high levels of heat and light reflected off the light~olored mill tailings that will inhibit plant photosynthesis. Addit- ional lime, nitrogen, phosphorus, and potassium will be incorporated into the organic fertilizer by raking and harrowing to a depth of about 6 inches, which will produce an even seedbed. The liming agent will be applied at a rate of appro. ' .:,ply 5 additional tons per acre, while the chemical fertilizer will probably be applied at a rate of between 40 ^^a F5 pounds per acre. This preparatory ground work will create a properly conditioned environment for rapid seed germination. The same seed mixture of both native grasses and introduced species that will be planted on the three eloping aides of the tailings embankment will be used on the former tailings pond. The seed mixture will be planted at the rate of about 40 pounds per acre by hydroaeeding. A Brillion grass seeder may also be used on this part of the tailings impoundment area.