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equivalent of 2 shares per acre or 0.017 cfs per share. Located in Appendix C is a copy of the <br />water court decree and historical diversion records for the Last Chance Ditch. <br />The NRCS Irrigation Water Requirement program, based on the Blaney-Griddle <br />method of calculating water consumption of crops, was used to calculate consumption of grass <br />hay neaz Rifle, Colorado. Net irrigation requirements for grass hay is 24.22 inches in a year <br />with normal rainfall or 2.02 acre-feet per acre of water consumption by the crop. There will <br />be 11.6 acres removed from irrigation in Area 1 and 9.6 acres removed from irrigation in Area <br />3. The total calculated consumptive use credits for the 21.2 acres taken out of irrigation is <br />42.39 acre-feet. The crop summary data sheet from the Irrigation Water Requirements <br />program is located in Appendix C. <br />Since the mining will start in Area 1 and will proceed east to Area 2, and finally to Area <br />3, three Water Balance scenarios have been developed. Table 5, is a Water Balance for Area 1, <br />Table 6, is a Water Balance for Area 1 and Area 2, and Table 7, is a Water Balance for Areas 1-3 <br />of the Scott Pit. The tables balance the evaporative depletions against the respective <br />phreatophyte and irrigation credits. Tables 5 through Table 7 are located in Appendix D. <br />Operation of Substitute Water Supply Plan <br />With the initiation of the gravel mining at the Scott Pit, all irrigation will cease and the <br />historically irrigated hay meadows will become staging azeas for the mining. All depletions at <br />the Scott Pit will first be augmented by consumptive use credits gained from the removal of <br />phreatophytes where the gravel pits will be excavated, and secondarily, the irrigation credits will <br />be used. <br />During all phases of the mining, phreatophyte and irrigation credits exceed evaporative <br />depletions and water lost in the mining process. Below is summary of the Depletions and the <br />Credits at the Scott Pit during the call period of April 15 through October 31. <br />Scott Pit <br />Water Balance <br />Jan Feb Maz Apr May Jun Jul Aug Sep Oct Nov Dec Total <br />Depletions 0.0 0.0 0.0 8.08 22.25 30.97 31.85 28.49 17.51 10.53 0.0 0.0 149.68 <br />Credits <br />Phreatophytes 0.0 0.0 0.0 8.05 22.93 28.96 33.75 30.03 20.70 12.01 0.0 0.0 156.43 <br />Irrigation 0.0 0.0 0.0 1.49 5.41 8.54 10.87 9.21 5.15 1.72 0.0 0.0 42.39 <br />Total Excess 0.0 0.0 0.0 1.46 5.41 6.53 10.87 9.21 5.15 1.72 0.0 0.0 40.35 <br />Irrigation Credits <br />4 <br />