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Peter Kearl <br />November 14, 2008 <br />Page 2 <br />the weight of the material. Four percent of the weight of the material equates to 0.0294 AF of <br />water per 1,000 tons of aggregate and sand washed, as shown in the equation below: <br />Depletion of Water from Washing 1.000 Tons of Material <br />0.04 /1,000 tons x 2,000 Ibs/ton x 0.1198 gal/lb x 1 acre-foot /325,851 gal = <br />0.0294 (acre-feet/1,000 tons) <br />Based on 40,000 tons per month, the calculated depletions of water from gravel washing total is <br />1.18 AF/month of water (0.0294 acre-feet/1,000 tons X 40,000 tons). The annual water <br />depletions based on 120,000 tons per year is 3.53 AF per year (0.0294 acre-feet/1,000 tons X <br />120,000 tons). <br />Total Water Depletions <br />The total annual water depletions from the material washing (3.53 AF/Yr) and evaporations <br />(0.61 AF/yr) totals 4.14 AF. <br />Water Supply <br />The Simmons property is irrigated by the Carpenter and Mitchell Ditch and storage water from <br />Jackson Gulch Reservoir. As reported in the Warranty Deed for the property, Simmons owns <br />2.0 cubic feet per second (cfs) out of 2.33 cfs decreed to the M-13 water right of the Carpenter <br />and Mitchell Ditch. It is important to note that the Jackson Gulch Reservoir water cannot be <br />used for the material washing. <br />A historical consumptive use (HCU) analysis was performed based on: <br />1) A review of a 2005 aerial photograph and historical irrigated area reported by the Colorado <br />Decision Support System. There is an estimated 85 acres of historical irrigated land. <br />2) The Cortez and Fort Lewis climate data interpolated based on elevation in relation to <br />Mancos, CO. The period of record of 1974 through 2004 is used in the analysis. <br />3) Daily diversion data for the Carpenter and Mitchell Ditch for streamflow as a source with no <br />allowance for storage water for the period of 1974 through 2004. The diversion data was <br />adjusted for Simmons ownership of 2.0 cfs out of 2.33 cfs of the senior M-13 water right. <br />It is important to note that there are water shortages in the ditch starting in starting in July during <br />average years and starting in June during dry years. There is usually very little water available <br />in August and September of most years. During the 2002 irrigation season there was not water <br />available during the irrigation season.