2011-01-03_PERMIT FILE - M2011001 (9)

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Post Pumping and first Fill Depletions Post pumping and first fill depletions upon cessation of mining are listed in Attachment G-3. A one-time augmentation requirement will be assessed at the time the pit fills. This will require a volume of approximately 1,066 acre-feet. Steady State Mining Depletion The steady state mining depletion uses at the mine will include evaporative losses, water used for dust control, and water consumed in the mined material removed from the site. The mine consumptive use volumetric projections are described in Attachment G-3 and are approximately 15.97 acre-feet per year. The following steady state operational losses are based on consumptive rates established in a letter from Applegate Group Inc. dated October 21, 2010 (see Attachment G-3). The moisture content of the material removed from the site is two percent by weight as required in the State Engineer's Office (SEO) Guidelines for unwashed material mined below the water table in a dewatered state. The anticipated annual production for the mining site is 600,000 tons of aggregate material. This results in an annual consumptive use of 8.3 acre-feet for water retained in product. Lafarge will apply water to haul roads and stockpiles for dust control. The estimated annual consumptive use for dust control is 6.0 acre-feet with a distribution throughout the year based on the same percentages as the production of the aggregate mined. The estimated annual consumptive use due to evaporative losses is based on an exposed groundwater area of 0.4 acres in the proposed dewatering trenches. The resulting evaporative loss is distributed unevenly between the months, with a total of 1.14 acre-feet per year. The mine consumptive use volumetric projections are described in Attachment G-3 and total approximately 15.97 acre-feet per year. Post-Reclamation Depletion Following reclamation of the site, an unlined pond approximately 44.4 acres in size will remain. Annual depletions resulting from evaporation from the pond surface is estimated to equal approximately 129.72 ac-ft as described in Attachment G-3. Augmentation In this area there is a potential for a call year-round, meaning that all depletions from the mining operation could potentially be out-of-priority and would require augmentation. The property owners, Tim and Jeanne Iverson, are responsible for supplying all of the water required for augmentation during mining and after the mine has been reclaimed per the lease agreement they have with Lafarge West, Inc. The Iversons currently own some Greeley Irrigation Company (GIC) water that they plan to use and they will purchase additional water to meet the augmentation requirements, prior to Lafarge initiating mining. Iverson Mine DRMS 112 Reclamation Permit Application Page G2 of G3