2024-06-03_REVISION - M1977170 - Laserfiche WebLink

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EXHIBIT D Mining Plan Methods Mining activities will be a continuation of the methods used for the past two decades at this location. Open pit mine excavation will be done by excavators and front-end loaders. Boulders larger than 3 feet are visually separated before the bank run material is fed to a dry screening plant. Through a combination of grizzlies and screens,products are segregated to surge piles before transport by loader and/or truck to stockpiles.No blasting is used. The majority of products are sold as cobble rock for landscaping cover.Typically, once each year, a subcontractor is brought in with crushing equipment to produce crushed rock and road base for construction applications. Crusher fines are a by-product that is sold for asphalt mixes. The pit run material contains approximately 40%sand which is sold for numerous purposes. Dry screened sand(<1/2")is sold for bedding, fill, concrete mix, etc. Some sand is rescreened and washed to produce specification concrete sand(<3/8")and masonry sand(<1/4). Pea pebbles are a by-product of this screening.This wash screening and stockpiles takes place outside the permit area. Previously,two pits have been excavated to approximately 25 feet by first removing 1-3 feet of overburden,then proceeding across the pits with high, side wall excavation.The North pit has been fully mined to the first 25-foot level with a pit floor of approximately 10 acres.The South pit is currently nearing completion of the first 25-foot level and will have a pit floor of approximately 23 acres. Products Shipments for 2021 totaled 167,320 tons and for 2022 the total was 175,030 tons.As stated above,the majority of products are coble for landscape cover. These include various sizes: 1/4"-1/2"pebbles, '/z"xF, Fx2", 2"x4", 4"x8", 8"x20", and various size boulders up to 10'. Cobble is mostly grey colored granite which has been smoothed by several geological events which transported and deposited the material from the upper Arkansas Valley areas.A lesser mix of other rock, mostly metamorphic, can be found.A distinctive trait of this formation is the lack of fine(<#400)or soluble material. The sands are clean of clays and have very little silt. Sands are produced by dry screening for bedding, fill and leach fields. To meet ASTM specifications, some sands are washed for concrete and masonry mixes. In addition to landscape cover and sands, construction angular aggregate is produced by crushing cobble rock. This is typically sized to<3/4" and accounts for about 7% of tons shipped. Pit run is also crushed to make road base which represents about 12%of tons shipped.A crushing by-product is crusher fines (<1/4")which are sold for bedding material and asphalt mixes. Roads Within the pit, roads are provided for m*ining equipment to haul and distribute products and for trucks to ship products. Most products are stockpiled on the pit floor for loading shipments. Roads and ramps are at least 30'wide with slopes less than 10% and are kept graded for smoothness.Water is applied to prevent excess dust. Signage is in place for truck drivers. Radios are used by all equipment operators to coordinate traffic. CB radio contact is used for truckers. Customers with small vehicles or trailers are usually not directed to the pit but are loaded from small stockpile bins near the office. Restrictions Between the two pits, a 6.6-acre Mine Restriction Area(MRA)bordered by Buffer Area(BA)exists in accordance with the 2000 US District Court Consent Decree"Remedial Design/Remedial Action for Operable Unit 2 Smeltertown Superfund Site"which implemented restrictive covenants on the use of the property. The BA has been excavated to a depth of 20 feet per the covenants.Additionally, approximately one acre was excavated to a depth of 20 feet within the MRA but was discontinued when