2019-06-28_REVISION - M1977004 (9)

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Homestake Mining Company May 10,2019 Regular(112d)Operation Reclamation Permit Application Package quaking aspen, park-like openings in the forest dominated by grass and forb rangeland, and shrub thickets of mountain mahogany, snowberry, and serviceberry. Prior to mining, most of the pit and rock dump areas were covered with dense stands of relatively small diameter lodgepole pines. Their dense (and shallow) root systems, combined with thin, poorly developed soils and steep slopes, rendered topsoil segregation impractical and little topsoil was able to be salvaged. Replanting lodgepole pine as a revegetation method is also impractical and has met with limited success. Revegetation of rock dumps and pit slopes therefore focused on broadcasting grass and forb seed, and planting seedlings of woody species on selected areas. Despite short growing seasons and harsh winters, initial survival of most woody species in the revegetation trials over the life of the reclamation of this site were successful. However, most of these plantings that were carried out have not successfully established or grown due to severe browsing pressure by wildlife; therefore, planting seedlings of these tree and shrub species will not remain in the proposed revegetation plan amendment. However, HMC has determined that some of the lodgepole pine stands, in the permitted area but outside the area affected by mining- related activities, could be improved by logging. Tree slash (which includes the pine cones) will be scattered where it is possible, which is a proven method of regenerating these trees. Cutting will be carried out mainly outside the disturbed area, but scattering slash can extend into the margins of the affected areas. Though the tree cutting and scattering of slash will be carried out as a land management tool and, it can complement disturbed area reclamation, it should not be considered as site disturbance or a regulated reclamation activity. Revegetation has been in progress since the reclamation permit was issued in 1977, beginning with roadcuts and miscellaneous areas that were hydroseeded and hydromulched, with good success. Revegetation efforts since the 1984 amendment, on larger areas of disturbance, have consisted of seeding with grasses and forbs, seeding shrub species, and planting seedling shrubs and trees. In addition to field reclamation, revegetation research was implemented to determine those species and reclamation methods applicable to the site. The primary revegetation scheme in the future is to create a grassland on sloping areas and on relatively level areas. Since the grass and forb seed mixes have been shown to be the most effective, efforts going forward will focus on seeding disturbed areas to grass and forbs. The specified seed mix, currently approved in TR-009 (CDRMS, 2018) and in use at the site, will continue to be used on most areas during final reclamation; these areas are predominantly below 10,000 ft on minor disturbances, such as road cuts. Disturbed areas, such as rock dumps, graded pit slopes, and areas adjacent to riprapped drainage control structures across the permit area will be prepared and seeded using the mix shown on Table 4-1. Seedbed preparation will be accomplished during the regrading operation. Slopes will be left in a roughened condition with flatter areas being scarified during regrading. Slopes will be worked on contour where practicable. On areas with slopes gentler than 3H:1 V, seed may be drilled at the proper drill-seeding rate, or broadcast at the broadcast rate and then lightly dragged to provide good seed-to-soil contact using a chain harrow or similar type implement. (Due to the prevalence of rocks at the surface EXHIBIT E-RULE 6.4.5(AMENDED RECLAMATION PLAN) Page 64 HOMESTAKE MINING COMPANY