2004-05-19_REVISION - M1979205 (2)

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dewatering will begin on Mining Area 2. Either a major settling pond will be created or pumping lines will be run to the Mining Area 1. Dewatering trenches will be installed similar to Mining Area 1. Also as mining progresses towards the north and west in Mining Area 2, irrigation of the oxbow wetland will begin. The minor settling pond for the irrigation can be seen in Map C-2 and C-3. Once mining has neared completion in Mining Area 2, Mining Area 1 will be fully rec]aimed and thus allowed to fill with water. Initial dewatering will then take place for Mining Area 3. Mining Area 1 will be used for the major settling pond for this phase. To maintain the oxbow wetlands both minor settling ponds will be used. Water will either be pumped from previous mining azeas or the current mining area to provide irrigation water. Once all mining has been completed all pits will be allowed to fill. A gravel well permit and augmentation p]an are currently being processed for the original pit. The Scott Expansion's permits will be filed concurrently with this application. Due to the close proximity of the pits to the Colorado River, the ground water table will be very high. It is also believed that a major contribution to the oxbow's water is passing under I- 70. This water is believed to originate from irrigation of fields to the east and south. Also irrigation previously was carried across the property. This has been re-routed to pass directly into the river prior to entering the property. The expected water table depth lies from 5-10' below the surface. This height will vary depending on the seasons. The following table shows the estimated amount and uses for water for the operation. Until operations begin and all equipment is in use, actual consumption will not be known. Operational Water Use Table Use Rate(glday) Duration (months) Annual Use(glyr) Annual Use(acrelft} Road Dust Control 3,000 I2 10,368,000 31.82 Asphalt Plant 500 6 864,000 2.65 Cement Plant 6,000 6 10,368,000 3].82 Gravel Evap. (4%byw 6,000 12 20,736,000 63.64 42,336,000 129.93 An augmentation plan and a gravel well permit have been obtained for the original Chambers operation. Prior to mining in the Scott Expansion Area below the water table, either an augmentation plan and gravel well permit will be obtained or the site's bond will be increased to cover the refilling of the pit at the end of mining. Due to the pit being near the City of Rifle water intake, a watershed permit issued by the City of Rifle may be needed. Issues involving this permit will be addressed prior to work beginning in the Scott Expansion Area.No wells are located in the surrounding vicinity which can be affected by the water drawdown from pumping. 4/26/04 Page G-2