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Peter Foster and Jonah Howe, Wright Water Engineers Page <br /> Re: Gunnison West Gravel Pit SWSP, Amendment No. 1 <br /> December 12, 2025 <br /> depletions. A potential call scenario is shown in column 7 of attached Table 3, indicating <br /> that out-of-priority depletions will be replaced with the exception of April. <br /> If a call is placed in April, and historical consumptive use credits are not available to replace <br /> all depletions, additional replacement water will have to be obtained from Blue Mesa <br /> Reservoir. Blue Mesa Reservoir is located immediately downstream of the Gunnison West <br /> operation, with a decreed capacity of 1,064,744 acre-feet, and provides releases to the <br /> Gunnison River for power and upper Colorado River storage purposes. <br /> The operation of the Blue Mesa Reservoir typically determines the downstream call regime; <br /> therefore, the timing of lagged depletions and return flows is not necessary to consider in <br /> this SWSP. This is because the timing of depletions and return flows will be offset by storage <br /> and operation of the Blue Mesa Reservoir, which does not require lagging to the river to <br /> avoid injury. <br /> Long-Term Depletions <br /> In accordance with the letter dated April 30, 2010 from the Colorado Division of <br /> Reclamation, Mining, and Safety (DRMS), all sand and gravel mining operators must comply <br /> with the requirements of the Colorado Reclamation Act and the Mineral Rules and <br /> Regulations for the protection of water resources. The April 30, 2010 letter (attached) from <br /> DRMS requires that the Applicant provide information to DRMS to demonstrate the Applicant <br /> can replace long term injurious stream depletions that result from mining-related exposure <br /> of groundwater. <br /> In accordance with approach no. 4, the Applicant has previously provided a letter dated <br /> April 30, 2013 that dedicates 3.125 cfs of the Applicant's 4.33 cfs in the Seventy-Five Ditch <br /> water as replacement water for out-of-priority depletions solely for this SWSP. This <br /> replacement water must remain dedicated to this site as long as there are depletions at this <br /> gravel pit site or until such time as another replacement source is obtained. For the <br /> purposes of this SWSP, this letter will be accepted for the dedication of the shares; <br />