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Mining Plan <br />1. Geoloev <br />Exhibit D <br />The site will mine a sand and gravel deposit which is an alluvium of the recent period of <br />Quaternary age. The alluvium is relatively shallow (less than 25 feet thick) and is underlain by <br />the sandstones, siltstones and mudstones of the Wasatch Formation. These sedimentary layers <br />were formed when uplifting Rocky Mountains to the east blocked eastwazd drainage during <br />Tertiary time and the Uinta Mountains blocked northward drainage and a very large lake formed <br />in northwest Colorado, northeast Utah and southwest Wyoming. This lake is referred to as Lake <br />Uinta and it received all the washout material from river floodplains and deltas from the <br />mountains on all sides of the lake. Some of the later mud which entered the lake became what is <br />now the Green River Shale, which is noted for its oil content. The Green River Shale forms the <br />hills immediately south of the permit azea. Lake Uinta lasted for 6,500,000 years until further <br />uplifts drained it. <br />2. General Mining Plan <br />The gravel zone is approximately 21 feet thick in an alluvial deposit and is overlain by topsoil <br />which averages 1.0 to 1.5 feet in thickness with approximately 2-8 feet of overburden until the <br />gravel deposit is reached. Higher overburden exists in the southeast corner of the property, which <br />will be part of the facilities azea which will not be mined. Sand and gravel aze the products <br />mined from this site. In general, the azea will be mined by first excavating any salvageable <br />topsoil with a dozer or front end loader and stockpiling it within the permit azea as shown on <br />Map C-2. The topsoil piles will have slopes no greater than 3H:1 V. Overburden will also be <br />removed and stockpiled. Topsoil and overburden will be stockpiled sepazately but both material <br />stockpiles will be seeded with the dryland seed mix presented in Table E-3 of the Reclamation <br />Plan after placement in order to prevent erosion. The raw gravel material will then be excavated <br />to within two feet of the bedrock surface and loaded into a crasher & screening plant and/or <br />washing plant where various sizes of product will be sorted and placed in separate stockpiles. <br />White River City Pit, April 07 D-1 <br />