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Mr. Forrest Leaf May 9, 2006 Page 2 be required for dust suppression and 22.25 acre-feet will be required for the production of 145,000 cubic yards of concrete. Dewatering of the site commenced in October 1998 at a rate of 300 gallons per minute and the plan anticipates that it will continue at this steady rate through 2007. All water pumped from the dewatering trenches is delivered to the Rural Ditch and discharged back to the St. Vrain River. The depletions from evaporation, water removed in product, dust suppression, concrete hatching and dewatering were lagged to the stream system using a Glover analysis and assuming a distance to the no flow boundary of 7,300 feet, distance of the well to the river of 5409 feet, transmissivity of 72,300 gpd/ft and specific yield of 0.2. The calculated lagged depletions are based on actual use at the site and account for all past use. Those lagged depletions are shown in attached Table 4. Replacements The proposed source of replacement for this pit is fully consumable water leased from the Town of Milliken ("Milliken") pursuant to excess augmentation credits from Milliken's SWSP filed under Division 1 Water court case no. 02CW339, 1 share of Rural Ditch and 5 shares of Kern Reservoir. The 1 share of Rural Ditch is a portion of 3.5 shares that were historically used to irrigate 125 acres, in combination with the Mayfield Seep. Historically the 125 acres supported alfalfa, corn, sugar beets and pasture grass. Assuming a 20% ditch loss and a 55% irrigation efficiency, the dry-year consumptive use of the 3.5 shares of Rural Ditch was determined to be 159.9 acre-feet. Therefore, the prorata consumptive use of the 1 share of Rural Ditch claimed under this plan is 45.6 acre-feet. The 5 shares of Kem Reservoir will be provided through releases from Kem Reservoir (a.k.a. Windsor Lake). The water that is subject of the Kern Reservoir water right is diverted from the Cache la Poudre via the Greeley No. 2 Ditch into Windsor Lake for storage pursuant to a 1934 agreement with the New Cache Irrigation Company. The 100 total shares of Kern Reservoir water were historically used to irrigate 728.3 acres. On These acres, a crop mix of 30% corn, 30% sugar beets, 30% beans, and 10% alfalfa was grown. Assuming a 10% ditch loss and 60% irrigation efficiency the dry year consumptive use for the 100 shares was determined to be 1,134 acre-feet. Therefore, the prorata consumptive use for the 5 shares claimed under this plan is 56.7 acre-feet. The use of a 60% irrigation efficiency in calculations of the historical crop consumptive use and return flows is acceptable in view of the fact that the historic supply is from releases from Windsor Lake which generally results in a readily available supply to the fields, and that those fields are relatively short and level and goad irrigation management practices were employed.