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• Ms. Michelle Johnson 25 Ave SWSP July 20, 2012 Page 3 combined total of 118.32 acre -feet per year. The applicant lagged this water Toss as per Exhibit 4 to the decree in 99CW231. Specifically, the IDS AWAS program was used with the following parameters: • X, distance from the well to the stream = 1,733 feet • W, width of the alluvial aquifer = 11,503 feet • T, Transmissivity = 1674,132 gallons per day per foot • S, Specific Yield = 0.20 The maximum lagged water Toss by year are 79.74 acre -feet for June through December 2012, 117.13 acre -feet for 2013, and 36.84 acre -feet for January through May 2014. See Table 1 for the monthly breakdown of all depletions associated with this SWSP. Replacement The primary source of replacement water for this SWSP is excess accretions generated by dewatering operations. Pursuant to paragraph 15 of the General Guidelines for Substitute Water Supply Plans for Sand and Gravel Pits (updated April 1, 2011), accretions that occur at the beginning of the dewatering operations may be claimed as replacement water to offset depletions that occur due to the mining operations and the dewatering process, if the applicant can account for the amount, location, and timing of these accretions. For the purpose of this SWSP, accounting for the dewatering depletion /accretion on a monthly basis is acceptable. Therefore, the dewatering operation must be metered with a totalizing flow meter that is read at least monthly and the dewatering operations must operate so that it can be reasonably assumed that all water dewatered in a given month is returned to the river in that same month. Depletions to the river may no longer be replaced in time and amount by dewatering accretions should the actual dewatering rate be Tess than the projected steady state of 850 gallons per minute. Should dewatering accretions no longer be able to provide replacement water for evaporative losses, Greeley's existing augmentation plan (water court case 99CW231) may be used instead. Alternatively Greeley may elect to utilize various water rights owned or controlled by the City of Greeley in the Cache la Poudre basin. In particular, Greeley may use 138 shares in the Boyd and Freeman Ditch that were previously owned by Flatiron Paving Co. and used in previous gravel pit SWSPs for Greeley West Pit. Attached Table 3 summarizes the historical consumptive use and return flow factors for the 138 Boyd and Freeman Ditch shares. Greeley now owns these shares and will dedicate these shares as a replacement source in this SWSP. Greeley may also release legally stored water from Flatiron Pits 1 and 2 (Poudre Ponds) pursuant to its storage rights in water court case no 99CW234, which are decreed for augmentation purposes. Table 4 presents a list of Greeley's water rights, and includes other fully consumable sources which may be used for augmentation in this plan. SWSP Conditions of Approval I hereby approve the proposed substitute water supply plan in accordance with §37 -90- 137(11), C.R.S. subject to the following conditions: 1. This plan is approved with the effective date of June 1, 2012 and shall be valid through May 31, 2014 unless otherwise revoked or modified. If this plan will not be made absolute by a water court action by the plan's expiration date, a renewal request must be submitted to this office with the statutory fee of $257 no later than April 15, 2014. 2. Well permits no. 58476 -F and 59809 -F were previously obtained for these pits but will no longer be valid with the implementation of this SWSP. A new well permit application has been submitted to this office and is pending on approval of this plan. The provisions of § 37-