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Mr. Richard Raines Page 5 Middle Poudre Combined Plan -Lafarge West, Inc. January 26, 2007 accretion credits for 2007. The lagged accretions to the Cache la Poudre River are estimated to total 668.87 acre-feet for this approval period (includes carry over from recharge in previous years). The Three Bells site was continuously dewatered at a rate of 1,200 gallons per minute. The timing of the lagged depletions from the dewatering operation was determined through a stream depletion model for the Three Bells Pit. The model addresses the lagged depletions at the Greeley 35`h Avenue Pit, East Rigden Pit, Kyger Pit, Port of Entry Pit and Weizel Pit by accounting for the net accretion credits at the river that occur due to the dewatering operation at the Three Bells Pit. These accretions are applied to this plan against depletions from the Greeley 35"' Avenue Pit, East Rigden Pit, Kyger Pit, Port of Entry Pit and Weizel Pit. The attached Appendix D summarizes the accretion credits from dewatering at the Three Bells Pit. During the Water Year 2007, a lease from the LCRC will make replacements for depletions not covered by the recharge program. A lease of 67.63 acre-feet of fully consumable water from LCRC will make replacements from February 2007 through July 2007. A copy of the LCRC lease was submitted to this office on December 28, 2006. The source of the replacement water will be from Gray Lakes, which can deliver water to Box Elder Creek and from there to the Cache La Poudre River. Approximately 3.53 acre-feet of water (0.25 percent per stream mile) from the Gray Lakes are estimated to be required to replace transit losses. The water storage right for the Gray Lakes owned by LCRC is not presently decreed for augmentation, therefore a change of use application for the Gray Lakes water storage right was filed with the Division 1 Water Court in case no. 2006CW276. A detailed historical consumptive use analysis has not . been provided in case no. 2006CW276. According to previous information provided byTZA Water Engineers, Inc. (`TZA") in a letter dated March 15, 2006, LCRC water rights have historically been used to provide supplemental water to irrigated lands within the Lake Canal Service area. Based upon the crop mix, irrigated acreage and water available for irrigation, TZA concluded that the Lake Canal system is water short. TZA also noted that a historical consumptive use of 65% is not uncommon for the use of supplemental reservoir water within water short ditch systems. For the purposes of this plan, the consumptive use associated with the Gray Lakes water was assumed to be 50%. This also means 50% of the delivered water constituted historical return flows, which must be maintained. Therefore, in addition to the 67.63 acre-feet of water to be released for replacement purposes, an additional 67.63 acre-feet (for a total storage release of 135.26 acre-feet) representing the return flow component shall be release from Gray Lakes to maintain the historical return flow regime. By February 15, 2007, the Applicant is required to provide updated accounting to document the monthly amount and timing of releases to maintain the historical return flow obligations of the Gray Lakes water used for replacement purposes. The applicant is advised that if a subsequent request to use Gray Lakes water for replacement purposes is submitted without a detailed historical consumptive use analysis being provided to substantiate a larger credit, the consumptive use credit allowed will be limited to 45% for the Gray Lakes water (55% assumed to be return flow). A monthly breakdown of the stream depletions from the mining operations as well as the replacements is shown in the attached Tables 4 and 5.