2024-06-25_PERMIT FILE - M2024032 (2)

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will be stockpiled separately for use in reclamation. Once the surface layer has been removed, the rest of the overburden will be stripped and stockpiled separate from the surface layer. The active mining face will extend no more than 500 feet in length. During mining and prior to reclamation, the mining face and side slopes will be a nearly vertical to 1/2H:1 V slope (see Exhibit C-5, Pre-Mining/Mining Plan Map). Mining will progress down to the depth of quality aggregate material or 20 to 25 feet below the surface. As the mining face progresses, pit sidewalls behind the mining activities will be reclaimed. So reclamation activities do not interfere with mining 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 is not limited to dozers, loaders, scrapers, and excavators. Aggregate material from the pit will be temporarily stockpiled within the pit or transported directly to the on-site processing facility or off-site for processing and use. 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 will be 50 feet or greater. Setbacks from near vertical mining excavations to the permit boundary will be a minimum of three times the adjacent pit depth to mitigate stability risks. Topsoil and overburden material removed prior to pit excavation will be stockpiled and used for backfilling mine pit slopes and other reclamation activities as needed. The non-marketable material stockpiles will be created adjacent to the areas that will need to be backfilled. When sufficient material is available in the stockpile, the material will be backfilled into previously mined areas. Alternatively, stockpiles will be created to minimize noise or visual impacts from the mining operations. The side slopes of the mine pit will be backfilled, graded to a minimum 3H:1 V slope, and seeded as mining progresses. Approximately 6,000 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 6,000 feet. Although the maximum pit depth is estimated to be between 20 and 25 feet in some locations, the average pit depth, and side slope, is anticipated to be near 15 feet. Where the material processing area is to be located, the pit depth is anticipated to be approximately 10 feet below the existing ground surface. 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. SJ Pit DRMS 112 Permit Application Page 6