2019-01-09_PERMIT FILE - M2019001 (3)

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operations, pit sidewalls may extend 500 feet behind the active mining face without being reclaimed. The aggregate material will be recovered using equipment typical for sand and gravel mining operations. Earth moving equipment may include, but are not limited to dozers, loaders, scrapers, and excavators. The aggregate material from the pit will be temporarily stockpiled within the pit or transported directly to the processing facility. During mining and reclamation activities, watering trucks for dust control will be used as needed. Setbacks from the mine pit top of slope to the proposed permit boundary or man-made structures not owned by the applicant will be 25 feet or greater. For setbacks adjacent to a man-made structure not owned by the applicant that are less than 25 feet, an agreement will obtained from the property owner or an engineering slope stability analysis will be performed. Setbacks from near vertical mining excavations to the permit boundary will be a minimum of twice the adjacent pit depth, but never less than 25 feet, to mitigate stability risks. Topsoil and overburden material excavated from the pit will be stockpiled separately and used for backfilling mine pit slopes and other reclamation activities. The non-marketable material stockpiles will be created adjacent to the areas that will be backfilled. When sufficient material is available in the stockpile, the material will be backfilled into previously mined areas. The side slopes of the mine pit will be backfilled, graded to a minimum 3H:1 V slope, and seeded as mining progresses. Approximately 15,000 feet of pit side slopes will be created during mining. Since reclamation is anticipated to be concurrent with mining operations, the actual length of side slope requiring backfilling and grading at any point in time is expected to be far less than 15,000 feet. Since the pit depth is estimated to be about 10 feet, the typical side slope is expected to be 10 feet high. Once backfilling and final grading has been completed in an area, the top of the slope and the side slopes will be seeded as soon as practicable (based on first available seeding season). Since reclamation will take place concurrently with mining, large and long-term topsoil and overburden stockpiling is not anticipated. Topsoil and overburden stockpiles will be configured to have side-slopes no steeper than 2H:1 V. If the stockpiles are inactive for more than one growing season they will be seeded with the fast growing grass seed mixture in the table below. However, since the stockpile materials will continually be used for reclamation, the stockpiles will likely be disturbed on a frequent basis and seeding the stockpiles may not be practical during the course of the operation. If stockpile seeding is not used, surface roughening will be maintained to limit wind and water erosion. Stockpile Grass Seed Mixture Grass Species Rate (lbs PLS/acre) Intermediate Wheatgrass 5.0 Blue Grama 1.0 Triticale (sterile hybrid of wheat and rye) 1.25 Rates are for broadcast seeding. Lazy Two Pit DRMS 112 Permit Application Page 7