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Y <br />1 <br />Mr. Richard Raines March 17, 2009 <br />Middle Poudre Combined Plan - Lafarge West, Inc. Page 4 of 9 <br />The total lagged mining depletions for all the seven sites is 426.9 acre-feet. Steady state <br />conditions were used for the Port of Entry Pit. However, real time depletions were used for Greeley 35`h <br />Avenue, East Rigden, Three Bells, Kyger, Weitzel and Shields Mine Pits because equilibrium has not yet <br />been reached. Since the Kyger Pit has recently experienced a reduction in the rate of mining, the lagged <br />depletions are higher than the current depletions, as the higher production rate is still affecting the <br />current depletions. The 8.8 acre-feet of water used in concrete production at the Greeley 35th Avenue Pit <br />is to be appropriated from well permit no. 47856-F. <br />Replacements <br />Replacement water for this combined plan will come from the following sources: accretion credits <br />from recharge of 8.5 shares of the Box Elder Ditch, accretion credits from dewatering at the Three Bells Pit, <br />and a lease from the City of Greeley ("Greeley") for fully consumable effluent. <br />In previous plans, Lafarge has used historical consumptive use credits from its share of the Boyd <br />and Freeman Ditch which were historically used for irrigation on the Greeley 35th Avenue Pit mining site. <br />However, Lafarge and Greeley have entered into a long-term lease agreement where Lafarge will trade its <br />ownership in the Boyd and Freeman Ditch for augmentation water from Greeley. Therefore, for the period <br />of this plan, the Boyd and Freeman Ditch shares will not be used for replacement purposes in this plan. <br />Greeley anticipates installing an augmentation structure and measuring device in 2010 and may request to <br />utilize Boyd and Freeman Ditch shares in another plan at that later time. Since Lafarge did use its Boyd <br />and Freeman Ditch share for replacement purposes in the previous plan, this plan will account for and <br />replace the non-irrigation season return flow obligation of 16.6 acre-feet (see column 2 of Table 1). <br />The source of replacement water for the winter months at the Greeley 35th Avenue Pit and the <br />other sites included in this combined plan will be from 8.5 Box Elder Ditch shares. Lafarge owns 8.5 <br />shares in the Box Elder Ditch and will use all of the shares in this combined plan. The shares will be <br />diverted into a recharge pit through an existing lateral from the ditch. The recharge pit was constructed <br />on the un-mined portion of the Three Bells Pit site and it was excavated to only the upper portion of the <br />gravel deposit and will not expose additional ground water. The estimated recharge pit size is one acre. <br />For the purposes of this plan, evaporation from open water was assumed for the entire surface area of <br />the recharge pit for the number of days water was diverted into the recharge pit. Based on this <br />approach, the proportion of days with water diverted into the recharge pit to the number of days per <br />month was applied to the monthly gross evaporation rate, resulting in an evaporative consumptive use <br />from the recharge pit of approximately 2.04 acre-feet. <br />Lafarge owns 5,5 shares of the 6.0 shares of the Box Elder Ditch that were historically utilized for <br />the irrigation of the Three Bells property (344.3 acres). The dry-up acreage claimed for Lafarge's 5.5 <br />shares would be 305.6 acres of the 344.3 historically irrigated acres on the Three Bells property. The <br />historical consumptive use credit of the 5.5 Box Elder Ditch shares associated with the Three Bells <br />property was determined to be 281.4 acre-feet, based on a historical consumptive use analysis that was <br />completed in support of an application for an augmentation plan pending in case no. 2002CW205. <br />Lafarge also owns 1 share of 3.5 shares historically utilized for the irrigation of the Robert <br />Weitzel Farm (145 acres) and another 2 shares of 5 shares historically used for the irrigation of the <br />Louis Swift Farm. The Robert Weitzel Farm is no longer irrigated due to the mining at the Weitzel Pit <br />and the adjacent Stute Pit operated by Connell Resource, Inc. The dry-up acreage claimed for Lafarge's <br />1 share would be 41.4 acres of the 145 acres historically irrigated on the Robert Weitzel Farm. The <br />Robert Weitzel Farm property is no longer irrigated and includes the 66.7 acres of ground water lakes at