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Mr. Jared Dains . SerFer Pit M- 2008 -006 October 11, 2011 Page 2 The lagged depletions from the SerFer Pit were estimated by the Applicant's consultant using the Alluvial Water Accounting System (AWAS) stream depletion model developed by the Integrated Decision Support Group with the following assumptions: • Distance from the gravel pit centroid to the river (X) = 600 ft • Alluvial aquifer width (W) = 4,300 ft • Specific yield (S) = 0.2 • Transmissivity (T) = 45,000 (gpd /ft) The stream depletion model shows that the SerFer Pit's stream depletion will equal approximately 4.45 acre -feet during the approval period as shown in the attached Table 3. Note that Tables 1 through 3 include actual values for January 2011 through July 2011, and projected values for August 2011 through March 2012. Replacements The source of replacement water for this plan is excess recharge credit from Connell Resources Timnath - Connell Pit (M- 1999 -050, WDID 0303018) SWSP (WDID 0302526) approved on August 29, 2011. As outlined in the Timnath - Connell SWSP, 2 shares of the Box Elder Ditch, owned by Connell Resources, are diverted into a recharge site at the Timnath - Connell Pit (WDID 0302059). The evaporation losses and operation of the recharge site are covered by the Tirnnath- Connell Pit SWSP. This recharge site is located approximately 4 miles upstream of the SerFer Pit location. Both the recharge site and the SerFer Pit impact the Cache La Poudre River. As such, a transit loss of 1.0% (0.25 % per mile) is assessed to the recharge credits to be used to at the SerFer Pit site. In accordance with the letter dated April 30, 2010 (copy attached) from the Colorado Division of Reclamation, Mining, and Safety ( "DRMS "), all sand and gravel mining operators must comply with the requirements of the Colorado Reclamation Act and the Mineral Rules and Regulations for the protection of water resources. The April 30, 2010 letter from DRMS requires that you provide information to DRMS to demonstrate you can replace long term injurious stream depletions that result from mining related exposure of ground water. The DRMS letter identified four approaches to satisfy this requirement. In accordance with approach no. 1 and 3, you have obtained a bond for $328,445 through DRMS for lining of the exposed ground water Conditions of Approval I hereby approve this substitute water supply plan, in accordance with § 37 -90- 137(11), C.R.S., subject to the following conditions: 1. This SWSP shall be valid for the period of July 28, 2011 through March 31, 2010, unless otherwise revoked, modified, or superseded by decree. 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 (currently $257) no later than February 1, 2012. 2. A well permit must be issued for the gravel pit in accordance with § 37 -90- 137(2) and (11), C.R.S. in order to expose or use groundwater. The SerFer Pit Well Permit 67614 -F expired on October 16, 2010. The applicant must apply for a well permit for the SerFer Pit within 21