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Dan Platt Page 2 <br />February 4, 2015 <br />precipitation and result in a reduction of runoff from precipitation. You have calculated <br />maximum monthly depletions to the Fourmile Creek drainage based on the maximum number of <br />acres of zero - discharge area that will occur. Zero - discharge areas within the Fourmile Creek <br />drainage are subdivided into those overlying the volcanic diatreme (a more porous geological <br />area containing the mined deposits) and those outside the boundary of the diatreme. Capture of <br />precipitation is considered to affect stream flow on a lagged basis, and CC &V has computed <br />lagging for each area separately. Should the actual amount of a zero - discharge area be less <br />than the acreages used to compute the maximum depletion; actual depletion will be reduced <br />proportionally. <br />Second, there are sediment detention ponds at the site that, when containing water, will <br />evaporate water. Shown in the table attached are your estimates of maximum monthly <br />depletions from the ponds. Actual depletions will be assessed on any pond that contains a free <br />water surface for more than 72 hours using the monthly evaporation rates given in the table, <br />pond surface area, and number of days the pond contains water. <br />Finally, water is pumped back from an underdrain and spring collection system intended <br />to reduce potential hydraulic head at the base of the mine's engineered liner system. This <br />pumping will be metered and replacements made equal to pumping, in the following month. <br />You have estimated the depletions to Fourmile Creek as 88 acre -feet (262.39 acre -feet <br />total; 66.6 % is returned through the Carlton Tunnel) resulting from interception of precipitation <br />on the lined areas, 31.6 acre -feet from the detention ponds and 13.4 acre -feet from the pump <br />back system; totaling 133.0 acre -feet. You have stated that there are 0 acre -feet of depletions <br />to the West Beaver Creek drainage basin associated with lined areas, only 8.6 acre -feet from <br />the sediment detention ponds. The total replacement is thus 141.6 acre -feet. <br />REPLACEMENT <br />The sources of replacement water for the augmentation plan include the following: <br />City of Victor water rights <br />CC &V has an agreement with the City of Victor that provides up to 1,300 acre -feet per <br />year of augmentation water. The individual water rights are listed in the application and the <br />court case. <br />City of Colorado Springs <br />CC &V has an agreement with the City of Colorado Springs to purchase fully consumable <br />raw water. This water is considered to be a backup source, and will be released as needed and <br />if available. <br />Pueblo Board of Water Works <br />CC &V has a long -term lease with PBWW to furnish 400 acre -feet of fully consumable <br />water each year. This water will be stored in Wright's Reservoir via exchange or contract trade <br />and released as needed. <br />