PERMFILE62930 - Laserfiche WebLink

Home Browse Search

Mr. Hal Simpson ~ • July 25, 1994 Page 4 consumptive use is shown on Table 3. The average annual consumptive use of irrigation water is 126 acre feet. An estimate of the historic effective precipitation during the non-irrigation season was made using the Blaney-Griddle formula and a crop coefficient of 0.2. The ice cover months of January and February are not included in this analysis. The historic effective precipitation credit offsets the gross evaporation. Cooley will initially excavate 20 acres. The effective precipitation on the 20 acres, the gross evaporation, consumptive use credit, and the net evaporation are shown on Table 5. As shown the effective precipitation offsets the evaporation for all months. Depletions are more than offset by historic consumptive use during the irrigation season. Table shows the depletions from mining and the historic consumptive use credit. A total of 2.02 acre feet per year is needed from effluent during the winter season. Cooley plans to begin mining in August, 1994. Table 5 shows the schedule of depletions and credits for a calendar year. ~ Regardless of the beginning date the monthly depletions shown ~ will be valid for at least two years. The amount of effluent leased will be sufficient to replace the depletions and transportation loss. OPERATION OF PLAN During the irrigation season Cooley proposes to leave its Smith and Emmons share in Boulder Creek. We have discussed, and received verbal approval, for this method from the ditch board and superintendent. Effluent will be released once per month. Enclosed is our proposed accounting form and effluent lease with proof of payment. The accounting will be submitted monthly to the Division Engineer. Effluent releases will be made to St. Vrain Creek. As shown on Figure 1 the confluence of Boulder and St. Vrain Creeks is below the proposed pit location. However, there are no water rights between the pit and the confluence. The effluent is released J