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u Exhibit D Mining Plan • Revision N I -Page 4 0(30 (aJ Descriptions oflhe methods oj~mining to be employed in each stage of [he operations as related [o the surface disturbance on aJjected lands; The proposed sand and gravel mining pit property is approximately 38 acres in size, and is a square shaped property one quarter mile in size (1280 ft by 1280 ft). With the Ciry of Grand Junction, setbacks and buffers requirements, 32.5 acres will be mined for sand and gravel. The sand and gravel will be progressively mined across the permit area using open pit mining techniques. As mining for the sand and gavel at the highwall azea is performed, the mined areas behind the highwall will be backfilled using overburden from the next mined area and imported inett fill. As the backfill material is placed to fmal grade, the areas will be prepared for site reclamation. The mining operations will utilize standard heavy construction equipment during the sand and gravel mining operation. This includes equipment such as trackhoe excavators, Gont-end loaders, scrapers, graders, compactors, water trucks, dump trucks, rock crushers, conveyors, etc. The sand and gravel material will be crushed, screened, and stockpiled at the permit site. The operations will not be producing "washed" rock products. A portable scale facility will be located near the southwest comer of the site to track materials removed from the project site. Surface disturbance activities and disturbed areas are listed below: ACTIVITY MAX. DISTURBED AREA (ACRES) Haul Roads/Scales I Topsoil Stripping 15 Process Equipment (In Topsoil Stripped Area) 5 Material Stockpiles (In Topsoil Stripped Area) 5 Active Mining JBackfill Area (In Topsoil Stripped Area) 3 Settlement Ponds I Tvnica! Seuuence OJOnerations: (I) The area to be mined, material stockpile areas, and processing areas will be stripped of the existing top two to six inches of topsoil. The topsoil material will be stockpiled in the buffer areas near the mined azea. The stripped topsoil area will be no larger than 15 acres in size. The total volume of stockpiled topsoil is approximately 6.000 cubic yards. (2) Next, the overburden in the excavation pit area will be removed. The overburden highwall area is anticipated to be approximately 400-If long and 12-ft tall. The overburden will typically be hauled and used as backfill material behind the active sand and gravel highwall area. However, until a highwall area is constructed, the overburden material will need to be temporary stockpiled until area has been mined and is ready for backfill. Overburden removal operations will occur slightly ahead of the sand and gravel highwall area to minimize overburden from sloughing off into active sand and gravel highwall area. (3) The sand and gravel materials [o be mined are expected to be located at and below the groundwater table elevation. Therefore, in order to mine the sand and gravel and place the backfill material in the previously mined areas, the excavation pit area will need to be dewatered. Portable pumps will be used to dewater this area, and they will be moved as the