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Mr. Richard T. Raines Page 2 January 12, 2007 Overland Ponds Site 5.46 0.0 0.0 5.46 No Expansion North Taft 29 73 0 0 0 0 No Site . . 29 73 Total 63.13 14.7 2.0 79.88 It should be noted that the only consumptive use at the North Taft Hill Expansion Site and the Overland Ponds Site is the evaporation from exposed ground water. The mined material from the Overland Ponds Site will be conveyed to the existing facilities at the Home Office Pit for processing. Therefore the 14.7 acre-feet associated with mining of up to 500,000 tons of aggregate per year and 2 acre-feet per year. of water used for dust control listed in Table B.for-the Home Office Pit will in fact be from the Overland Ponds Site. According to the information provided, mining at the North Taft HiH Expansion Site ended January 2005. This site was continuously dewatered until the end of January 2005. After January 2005 the lake was allowed to fill, as the mining operation begun at the nearby Overland Pond Site. The post pumping depletions at the North Taft Hill Expansion Site were replaced during the previous approval plan by accounting for the net accretion credits at the river that occurred due to the dewatering operation at the Overland Ponds Site. .The source of replacement water for this combined plan will be from 5.75 Taylor and Gill `. Qitcfi ;shares:'The shares will be diverted into a recharge pit located on the Home Office site. Ths evaporation losses from the recharge',pond during this approval period are estimated at ' 2.58 acre-feet (Table1). In 2005 and 2006 the 5.75 Taylor and Gill Ditch shares were diverted into the. recharge pond 'for lagged replacement water. The 5.75 shares will be diverted in the recharge pond again in 2007 to provide replacement water for this combined plan. The 5.75 shares were historically used to irrigate 104.5 acres of pasture grass, all of which have been taken out of production. The historic consumptive use of the 5.75 shares was determined to be 122.8 acre-feet (includes consumptive use and return flows). The 5.75 shares will be diverted into the recharge pit each irrigation season. The return flow obligations from the Taylor and Gill Ditch will be maintained by the recharge plan. The attached Table 3 shows the farm headgate delivery of 5.75 Taylor and Gill Ditch shares. Lafarge plans to divert the full farm headgate delivery of 240.31 acre-feet into the recharge site each year (Table 3). A total of 309 acre-feet were diverted into the recharge site between April 20 and October 2, 2005 and a total of 58.1 acre-feet were diverted between April 27 and August 2, 2006. Lafarge will divert the full farm headgate delivery of the 5.75 Taylor and Gill Ditch shares starting in April 2007. Accordingly, the monthly timing of 240.32 acre-feet (full farm headgate delivery of the 5.75 shares) was used in the recharge model to determine the recharge accretion credits for 2007. The lagged accretions to the Cache la Poudre River are estimated to total 195.78 acre-feet for this approval period (includes carry over from recharge in previous years). During the Water Year 2007, a lease from the Tri-Districts will make additional replacements for the months with insufficient recharge credits. The total amount of water required including 7.8 percent transit losses is 16.10 acre-feet. A copy of the lease with the Tri- Districts was provided to this office on October 17, 2006 and is attached to this letter. A monthly breakdown of the stream depletions from the mining operation as well as the replacements made by lagged timing of the historic consumptive use credit is shown in the attached Table 1.