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NIINING PLAN 1. General Plan- Mining The gravel zone is approximately 30 feet thick in an alluvial deposit and is overlain by soi10-6 inches thick and clay overburden of 5'-20'. Test holes from Fall of 2003 show increasing overburden to the west. The gravel deposit will be mined to the shale bedrock layer or to the water table. Mining will stop when ground water is encountered, and all exposed groundwater will be promptly buried using overburden or excess fines from processing. The gravels aze Florida gravels of the Pleistocene age underlain by shales and sandstones of the Eocene Age. The mining azea is divided into two pits and the staging azea for all future mining. The North Pit as labeled in Map 3 will be mined fast in 2 phases progressing northwazds. The South Pit will progress towards the west and south as can be seen in Map 3. The mining of the deposit will occur to the limits shown on Map 3 and will be mined to a slope no steeper than 1 H:1 V. The maximum total tonnage sold from the site in any one calendaz yeaz will be 360,000 tons, though the expected annual average is 261,000 tons. The expected annual average is based on current Four Corners Materials production rates at Ewing Mesa. Once the Cugnini Pit begins full production the pit will produce a majority of Four Corner's local aggregate demand. The raw material will be processed and then sold in three main products: 3/4" gravel, 3" gravel and Asphalt. A break down of the product tonnages and mined tonnages can be seen in table D-l. No explosives will be used on-site for the mining operation. Avera a Annual Product Distribution roduct Tons Sold % Reject Rate (Naturals) Tons Mined kialt 142,000 46% 262,96 rushed Sand and Gravel 76,000 32% 111,76 er Aggregate 43,000 10% 47,77 oral 261 000 36% 422 50 Table D-1 North Pit The North Pit will be mined first. A breakdown of the estimated North Pit azeas aze included in table D-2. Mining in the North Pit will begin with the installation and/or maintenance of ditches #3,4, and 5. They provide isolation from the surrounding watersheds. These ditches are further described in Exhibit G. An isolation berm will be constructed along the downhill edge of the North Pit as the mining progresses northward. This berm will be constructed from bank material and most likely will be dozed in. The isolation berm can be seen on Map 3. Then Mining Area 1's topsoil will be stripped with belly scrapers and stockpiled in berms surrounding the North Pit, as shown on Map 3. The berms will be sloped at 2.SH:1 V with an approximate height of 3 feet. A triangular widening of the topsoil berm as seen on Map 3 will provide additional storage for excess topsoil. This berm will also provide isolation from the watershed to the west and north, as wells as, visual screening from the properties to the west. The raw gravel material will then be loaded into a portable crusher/screen plant where various sizes of product will be made and placed in separate stockpiles. Dozers may also be used to move topsoil or gravel. The portable crushing plant will typically operate for a total of 18 weeks intermittently each yeaz, although future demand may require crushing for up to 26 weeks per yeaz. Cugnini 12/03