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Air Don Lo loff RE Estimated Augmentation Plan Cost December 23, 2011 Page 2 of 7 river depletions also equal 99.28 acre -feet per year, but have a different timing than the evaporative losses as shown in Column (C) of Table 1. A replacement source or sources sufficient to replace the depletions at the correct time, location, and amount must be procured in order to have a valid augmentation plan. The location of the Loloff Pit indicates that the river depletions occur above the headgate of the Ogilvy Ditch which is a typical calling right during the irrigation season. According to the District 3 Water Commissioner, George Varra, during the severe drought year of 2002 the Ogilvy Ditch would have begun placing a call in late April and the ditch typically shuts off by the 1 of October. A review of the call records available online from the Division of Water Resources reveal that, since 2005, the Ogilvy has only placed a few calls, all of which were in the month of May. Based on this information, we assumed that any augmentation plan for the Loloff Pit must be capable of making replacements to the Ogilvy Ditch from May through September. Note that this assumption puts you at some risk given the potential that the Ogilvy Ditch could also place a call in April. We expect that a potential augmentation plan could handle this issue by authorizing you to obtain a temporary lease of augmentation water (from the City of Greeley, for example) should such an event occur in the future. When the Ogilvy Ditch is not placing a call, then the next water right that would be injured is located farther downstream on the South Platte River. Therefore, we assumed that replacements lower down on the South Platte would be adequate from October through April. GIC SHARES Currently, the GIC system is capable of making replacements to the Poudre River above the Ogilvy Ditch, making it useful for replacing depletions during the May through September timeframe. Augmentation credit from GIC shares is obtained by returning diverted water to the Cache la Poudre through augmentation stations; the historically consumed portion of the water may be claimed as a credit to offset your augmentation requirements. There currently exists an augmentation station on the ditch, operated by the ditch company, which could be used to return the shares to the river during the irrigation season, so there should be no added costs associated with constructing an augmentation station. The method for calculating augmentation credits in the GIC system is outlined in the decree for Case No. 96CW658 (commonly referred to as the "Poudre Prairie Decree "). This case involved a change of GIC water rights based on a ditch -wide analysis and can be relied upon in future change cases; it found that a GIC share yielded 10.31 acre -feet of consumptive use on average each year. In order to determine the timing of the yield of a GIC share, we utilized the findings in the May 1998 engineering report prepared in support of the Poudre Prairie Decree. Our investigation found that seven GIC shares would be required to ensure all depletions from the Loloff Pit are replaced during the May to September timeframe as shown in Column (F) of Table 1. We've previously estimated that a share of GIC costs approximately $50k; therefore, the total cost for acquiring the seven GIC shares would be approximately $350k. George Varra (District 3 Water Commissioner), telephone conversation with Jared Darns (Applegate Group), October 27, 2011.