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6.4.4 EXHIBIT D - Mining Plan (a) The description of the method of mining in each stage of the operation as related to any surface disturbance on affected lands. The narrative is presented in sufficient detail in the pemut application to provide a visual representation of the mining method. However, this should be correlated to an expanded map of the active mining area that clearly illustrates the features described in the narrative. For example, the locations of the overburden and topsoil stockpiles should be clearly shown on this map along with the locations of the sediment pond, the diversion ditches, etc. Furthermore, this map should represent the worst case disturbance for assistance in prepazing the reclamation liability estimate. This may include from 5-10 years of mining disturbance and reclamation illustrating the vazious phases from freshly stripped to fully reclaimed. From initial seeding until a phase is vegetated with aself- sustaining cover could easily take 5 yeazs and at least some portion of the financial warranty is required until it reaches this state in development. The location of the initial and active overburden and topsoil stockpiles aze important for calculation of the reclamation bond as well as determining the final disposition of these piles. Also, if this material is to remain in a stockpile for more than one growing season, it must be seeded with a temporary seed mix to protect it from erosion. Please provide a seed mix that will be appropriate for this use. (b) Earthmoving No comment at this time. (c) All water diversions and impoundments. This item requires further clarification. If the diversion and impoundment structures described in the permit application aze to be constructed and the water utilized for dust control, this will likely require that augmentation water be acquired from the State Engineer's office during mining. In addition, the design specifications for any containrnent structure, including storm event sizing, dischazge stmcture size and location, must be submitted along with general design specifications for diversion structures. Furthermore, the entire surface water control plan should be included on the mine plan map and/or the expanded 10 yeaz map to show how surface water run-off will be managed to protect against pollution both during and after mining. Upon final reclamation, there is a concern about how the pond will be passively dischazged and the watershed will be restored. During mining the pond can be dischazged through pumping as stated in the application, however, once mining is completed, how will the surface water run-off be allowed to flow unimpeded back into the St. Charles River? It presently appears that a permanent impoundment will be formed due to the elevation loss on the north end of the pit as the result of resource extraction. In other words, once 30 feet of limestone is removed and the first highwall is backfilled at