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<br />Augmentation <br />!n order to prevent injury of senior water rights along the St. Vrain Creek and South Platte River, <br />augmentation of the out of priority depletions at the site will be required. During mining of the <br />amendment area it is estimated that approximately 21.6 acre-feet of groundwater will be <br />wnsumed each year. A portion of the water rights listed on Table No. 1 will be committed to <br />augmenting the water use due to mining. <br />As stated earlier the final reclamation plan for the site is water storage reservoirs. Consequently <br />there will be no long term augmentation responsibilities. The amendment area reservoirs will <br />be sealed off from the surrounding alluvial aquifer to prevent groundwater infiltration. <br />Water Storage <br />The water rights listed on Table No. 1 will be used to fill the two reservoirs in the permit <br />amendment area. The two reservoirs in the original permit area will be filled with water rights <br />owned by C & M Companies. C & M Companies owns 15.9 percent of the Coffin & Davis <br />Ditch. This equates to approximately 103 acre-feet of headgate delivery and 52 acre-feet of <br />consumptive use based on a 50 percent irrigation efficiency. This water is currently being used <br />in an approved substitute water supply plan for existing operations. <br />The other source of water to supplement the filling of the four reservoirs will be junior water <br />storage rif;hts. These new water rights will be acquved through water court and they will permit <br />the diversion of water to storage during periods of no call on the river. During most winter <br />months anal during the peak of the spring runoff there is generally no call on the river. During <br />these periods water will be diverted to storage. C & M Companies is in the process of preparing <br />these water right filings and will provide copies to the DMG when they are wmpleted. <br />Surrounding Water Rights <br />Attached with this exhibit is a map showing permitted and/or adjudicated water rights within one <br />half mile of the site. Well data from the State Engineers's Office was used to locate the <br />surroundtrig wells and water rights. The State Engineer's Tabulation of the wells and water <br />rights is also attached. All wells lying on the opposite side of St. Vrain Creek will not be <br />impacted by the mining operation. The Creek serves as a hydraulic barrier to drawdown from <br />dewaterinl; operations. <br />9 <br />