2019-04-18_PERMIT FILE - M2019001

Home Browse Search

will be tilled with a dozer in preparation for topsoil/overburden growth medium placement. Approximately 1,650 cubic yards of topsoil/growth medium will be placed a minimum of 6 inches deep over approximately 2 acres using haul trucks or scapers and a John Deere tractor and drag will perform final grading prior to seeding for revegetation. Since quality topsoil is scarce on the Lazy Two Pit site, vegetation growth medium will include the best quality topsoil/overburden material available. Following backfilling, scarifying, and/or rough grading a minimum of 6 inches of growth medium will be placed on all relatively flat areas such as the material harvest area and the pit floor. On backfilled or otherwise created pit slopes, a minimum of one (1) foot of growth medium will be placed following backfilling, scarifying, and/or rough grading. Final grading of the topsoil/overburden growth medium will prepare the surface for seeding. After initial seeding and the first season's growth, it is estimated that approximately 20 percent of the seeded area will need to be re-seeded. Each aspect is listed in the following table with associated disturbed area. Please refer to Exhibit D, Pre-Mining/Mining Plan, for a listing of disturbed areas that total 124.3 acres. This estimate will follow the same order as the listing in Exhibit D. Connell Resources Inc. is an earth moving and construction contractor and unit costs for reclamation activities were provided from bidding documents associated with similar projects. Since all structures used in the mining operation are portable, it is assumed that removal of the structures do not have associated costs. Stockpiles with available topsoil/overburden for backfilling will be near the active mining area, pit, and other areas for reclamation, so haul distances will generally be less than 1,000 feet. A conservative estimate for backfilling/dozing the mining face and side slope highwalls to create 3H:1 V slopes is 12,000 cubic yards. If material needs to be hauled for backfilling, the applicant will use a CAT 345 excavator and CAT 740 rock trucks. However, other contractors may use scrapers for better efficiency. The applicant will perform dozing of the highwalls and/or rough grading with a CAT D9 dozer. The created side slopes and pit floor will cover approximately 13.8 acres and, if it is assumed that rough grading involves the top 6 inches of material, about 1,150 cubic yards of material will be moved during rough grading. The applicant will again use a CAT 345 excavator and CAT 740 rock truck to move approximately 22,300 cubic yards of topsoil/growth medium to the area and create 1-foot of cover, but other contractors may choose to use scrapers. The applicant will use a John Deere tractor and drag to final grade about 11,200 cubic yards of topsoil/growth medium over the 13.8 acres. Since more backfill material will be required to get the pit to drain freely, a material harvesting area will need to be created in a previously undisturbed area of site. Approximately 63,000 cubic yards of topsoil and 189,000 cubic yards of overburden will be stripped from the 78-acre harvesting area with scrapers. The topsoil will be temporarily stockpiled and the overburden will be placed over about 30.5 acres in previously mined areas as backfill. The haul distance will be less than 1,000 feet. The CAT D9 dozer will be used to rough grade the material harvest area and backfilled area (108.5 acres), moving approximately 87,500 cubic yards of material (assuming 0.5 cubic yards of material is moved during rough grading). The applicant will then use the CAT 345 excavator and CAT 740 rock trucks (contractors may choose to use scrapers) to place approximately 87,500 cubic yards of topsoil/growth medium to a minimum depth of 6 inches over the 108.5 acres. Finally grading will use the John Deere tractor and drag to final grade about 87,500 cubic yards of topsoil/growth medium over the 108.5 acres. Lary Two Pit DBMS 112 Permit Application Page 24