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The side slopes of the mine pit will be backfilled, graded to a minimum 3H:1 V slope, and seeded <br /> as mining progresses. Approximately 15,000 feet of pit side slopes will be created during <br /> mining. Since reclamation is anticipated to be concurrent with mining operations, the actual <br /> length of side slope requiring backfilling and grading at any point in time is expected to be far <br /> less than 15,000 feet. Although the pit depth is estimated to be between 8 and 12 feet, the <br /> average pit depth, and side slope, is anticipated to be near 10 feet. Once backfilling and final <br /> grading has been completed in an area, the top of the slope and the side slopes will be seeded as <br /> soon as practicable (based on first available seeding season). <br /> Since reclamation will take place concurrently with mining, large and long-term topsoil and <br /> overburden stockpiling is not anticipated. Topsoil and overburden stockpiles will be configured <br /> to have side-slopes no steeper than 2H:IV. If the stockpiles are inactive for more than one <br /> growing season they will be seeded with the fast growing grass seed mixture in the table below. <br /> However, since the stockpile materials will continually be used for reclamation, the stockpiles <br /> will likely be disturbed on a frequent basis and seeding the stockpiles may not be practical during <br /> the course of the operation. If stockpile seeding is not used, surface roughening will be <br /> maintained to limit wind and water erosion. <br /> Stockpile Grass Seed Mixture <br /> Grass Species Rate <br /> (lbs PLS/acre) <br /> Intermediate Wheatgrass 5.0 <br /> Blue Grama 1.0 <br /> Triticale 1.25 <br /> Rates are for broadcast seeding. <br /> In order to gain an understanding of the extent of the mining operation, it is helpful to know the <br /> acres disturbed by different aspects of the mining operation. Each aspect is listed in the <br /> following table with associated disturbed area. The table illustrates a point in time where the <br /> mining disturbance could be at its maximum. At the proposed Carr Pit East site, it is assumed <br /> that the mining disturbance will be at its greatest midway through Phase I. During this scenario, <br /> no reclamation will have been performed on the active mining face, approximately 500 feet of <br /> side slope on both sides of the mining face, and about half of the exposed pit bottom. Since <br /> backfilling side slopes and the active mining face to a minimum 3H:1 V slopes is more costly <br /> than "cut and fill" sloping, backfilling will be used to estimate reclamation costs (see Exhibit L). <br /> Carr Pit East <br /> DBMS 112 Permit Application Page 8 <br />