2012-09-06_REVISION - M2008070 (28)

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•; EXHIBIT D Mining Plan 1. Geology The site will mine sand and gravel deposit which is an alluvium of the recent period of Quaternary age. The alluvium is relatively shallow and is underlain by the sandstones, siltstones and mudstones of the Wasatch Formation. These sedimentary layers were formed when uplifting Rocky Mountains to the east blocked eastward drainage during Tertiary time and the Uinta Mountains blocked northward drainage and a very large lake formed in northwest Colorado, northeast Utah and southwest Wyoming. This lake is referred to a Lake Uinta and it received all the washout material from river floodplains and deltas from the mountains on all sides of the lake. Some of the later mud which entered the lake became what is now the Green River Shale, which is noted for its oil content. The Green River Shale forms the hill immediately south of the permit area. Lake Uinta lasted for 6,500,000 years until further uplifts drained it. 2. General Mining Plan The gravel seam for Phase 1 is approximately 10 feet thick and is overlain by 0.5 feet of topsoil and approximately 3 feet of overburden. The gravel seam for Phase 2 is approximately 8 feet thick and is overlain by 0.5 feet of topsoil and approximately 6 feet of overburden. For both Phase 1 and Phase 2 the mining operations (crushers, conveyors, dozers and scrapers) will be located in the Westerly portion of the respective gravel pit area. Utilizing dozers, scrapers and front end loaders, the topsoil will be stripped and be placed in berms along the North side of the project as a buffer along the steep embankment to the river valley. All topsoil piles will be seeded with a temporary seed mix with a tackifier if they will be left for over 1 year without redisturbance. Weeds will be controlled in all disturbed areas and on the entire site. The overburden will also be removed and stockpiled. The raw gravel material will then be loaded into a crusher and screening plant and/or washing plant where various sizes of product will be sorted and placed in separate stockpiles. There will be no blasting as part of this operation. Mining will proceed in general from the west to the east. The overburden will be replaced in the bottom as the operations moves to the east. All mining and processing operations will be designed to manage storm water runoff, so that no sediments flow to existing drainage. To ensure that water from inside the operation does not leave the site, isolation berms will be created as needed around the pit. The mining operation will proceed with side slopes of 2:1. It is extremely unlikely that any toxic or acid - producing materials will be encountered during the mining operation since the material is alluvial in nature. However, in the event that such materials are encountered, they will be covered with subsoil from the stockpiles to the same depths outlined in the reclamation plan and no more mining will occur in this particular area. - - - - - -- - - -