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Middle Poudre Combined SWSP Page 3 of 8 <br /> February 3, 2016 <br /> A stream depletion model using the Glover method was used to calculate the lagged <br /> depletions to the Cache La Poudre River. The alluvial aquifer model was used with the following <br /> aquifer input parameters: transmissivity (T) = 45,000 gallons/day/foot; the distance of centroid of <br /> the exposed ground water to the Cache La Poudre River (X) = 1,900 feet; the distance from the <br /> parallel impermeable boundary to the Cache La Poudre River (W) = 4,800 feet; and the specific yield <br /> (S) = 0.2. <br /> The depletions to be replaced under this SWSP are summarized in Table B below. A monthly <br /> breakdown of the lagged depletions can be found in the attached Table 1. <br /> Table B - Depletion Summary (all amounts in acre-feet) <br /> Evaporation Water Lost in Dust First Lagged Lagged Total <br /> Site Name Total Dewatering Lagged <br /> Loss Mined Product Control Fill Depletions <br /> Depletions Depletions <br /> Three Bells 33.19 21'57 19.33 N/A 91.58 90.23 Oa 90.23 <br /> Pit (732,725 tons) <br /> a So long as the site is continuously dewatered, the water returned to the stream system is considered to be <br /> adequate to offset depletions attributable to the dewatering. <br /> Replacements <br /> Replacement water for this combined plan will come from a combination of accretion credits <br /> from past recharge of 5.0 shares of the Box Elder Ditch Company and past and projected recharge of <br /> 1.0 share of the Box Elder Ditch Company. <br /> Lafarge previously owned and dedicated to this plan 5.0 shares in the Box Elder Ditch Company. <br /> The 5.0 Box Elder Ditch Company shares were sold but recharge credits continue to be available for <br /> replacement use under this combined plan for water that was delivered to recharge through the 2014 <br /> irrigation year. Accretions from past (2014 and earlier) recharge of the shares will continue to accrue <br /> to the stream in 2016 and beyond. In addition, the Applicant obtained approval from Steamboat <br /> Partners Investments, LLC for the use of their 1.0 Box Elder Ditch Company share in the 2015 and 2016 <br /> SWSPs. <br /> The Box Elder Ditch is divided into 64 Box Elder Ditch Company ("BEDC") shares. The 5.0 shares <br /> previously dedicated to this plan are from the group of 5.5 shares previously owned by Lafarge that <br /> were historically associated with the Three Bells Farm. The 1.0 share owned by Steamboat Partners <br /> comes from this same group of 5.5 shares. A total of 6.0 BEDC shares were historically utilized for the <br /> irrigation of 344.3 acres at the Three Bells Farm. The historical consumptive use credit for the 6.0 BEDC <br /> shares used to irrigate the Three Bells property was determined to be 307.0 acre-feet (51.2 acre-feet <br /> per share), based on a historical consumptive use analysis submitted with the 2014 SWSP request. <br /> Table 2 from the 2014 SWSP request shows the average ditch diversion for the Box Elder Ditch <br /> from 1950 to 2007. Table 3 takes the average ditch diversions for the Box Elder Ditch from 1950 to 1984 <br /> and analyzes the historic consumptive use and return flows for the 6.0 BEDC shares. Table 4 breaks this <br /> information down further to come up with the monthly historic farm headgate diversions and return <br /> flows for the 5.0 BEDC shares previously utilized in this plan. As shown on Table 4, the average annual <br /> farm headgate diversion associated with the subject 5.0 BEDC shares is 457.0 acre-feet (91.4 acre-feet <br /> per share) with an associated return flow obligation of 201.1 acre-feet (40.2 acre-feet per share). This <br /> leaves a net consumptive use credit of 255.9 acre-feet, or 51.2 acre-feet per share. <br />