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Mr. Forrest Leaf May 30, 2007 DEPLETIONS Currently 11.72 acres of ground water surface is exposed at the Ft. Lupton Mine, including 0.67 acres of dewatering trenches and 11.05 acres of silt ponds. Consumptive use from the operation of this site consists of 17.65 acre-feet of water lost in product (4% moisture of 600,000 tons of raw material), 3 acre-feet for on-site dust control, 1.53 acre-feet used in the production of 10,000 tons of concrete and 33.76 acre-feet of evaporation from the 11.72 acres of lake surface exposed after December 31, 1980. The total consumption at this site from mining operations is 55.95 acre-feet. The evaporation calculation has been accepted for this plan period, however any SWSP renewal request must demonstrate that the evaporation calculation is accurate for the specific location of the Ft. Lupton Mine. The depletions from evaporation and water lost in mined product were lagged to the stream using a Glover analysis and assuming a distance to the stream of 1,853 feet, distance to the impermeable boundary of 7,996 feet, transmissivity of 83,195 gaUday/ft and specific yield of 0.2. The depletions from well no. 57957-F (concrete production and dust suppression) were also lagged to the stream using a Glover analysis and assuming a distance to the stream of 690 feet, distance to the impermeable boundary of 7,996 feet, transmissivity of 100,000 gpd/ft and specific yield of 0.2. Attached Table 4 shows the total lagged depletions determined to accrue to the steam system during this plan period. REPLACEMENTS The 0.52 shares of the Lupton Bottom Ditch are part of 2.25 shares that were historically used to irrigate 95 acres of corn and small vegetables. The land historically irrigated by the 2.25 shares is the same land that is currently being mined at the Ft. Lupton mine. Assuming a 10% ditch loss and a 55% irrigation efficiency, the dry-year consumptive use of the 2.25 shares was determined to be 138 acre-feet. The prorated consumptive use and return flows for the 0.52 shares is shown in attached Table 4. The Lupton Bottom shares will be delivered back to the South Platte River at either the augmentation station located just north of WCR 14.5 or the Petrocco Augmentation station located just east of the pit. The nontributary Laramie-Fox Hills aquifer water will be withdrawn by an existing well pursuant to permit no. 65060-F. The well is currently permitted for industrial, commercial and augmentation use and is allowed an average annual withdrawal of 66 acre-feet and a pumping rate of 150 gpm. The Applicant's accounting includes the 2% relinquishment requirement for the nontributary Laramie-Fox Hills water. The water leased from the Town of Milliken ("Milliken") is excess augmentation credits available under Milliken's 2007 substitute water supply plans ("SWSP") approve pursuant to C.R.S. 37-92-308(4) on March 12, 2007. The court case associated with the Milliken SWSP is Division 1 Water court case no. 02CW339. The excess augmentation credits from Milliken accrue to the Big Thompson River in the vicinity of the confluence with the South Platte River. Conditions of Approval I approve the proposed substitute water supply plan in accordance with Section 37-90- 137(11), C.R.S., subject to the following conditions: