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2024-2025 Chavers Mining Resources Substitute Water Supply Plan Page 4 of 8 July 25, 2024 Lagged depletions for the period of August 1, 2024 through December 31, 2024 are as follows: (1) 19.58 acre-feet associated with the evaporation from the pump basin and dewatering trench and water lost with mined aggregate, (2) 4.52 acre-feet associated with the evaporation from the wash pond and dust control, and (3) 6.69 acre-feet associated with the water pumped from the alluvial well for concrete production, as shown on attached Table 4. The total lagged depletions for the period of August 1, 2024 through December 31, 2024 equal 30.79 acre-feet as shown on attached Table 4. Dewatering Dewatering at this site will produce delayed depletions to the stream system. As long as the pit is continuously dewatered at a relatively constant rate, the water returned to the stream system should be adequate to offset the depletions attributable to the dewatering operation. Dewatering operations must be measured by totalizing flow meters that can accurately show the monthly volume of dewatered water that is pumped and returns to the stream. Should it be determined by the Water Commissioner or Division Engineer that dewatering water is being diverted for any purpose by the operator and accounting is not adequate to show that 100 percent of the dewatering water is returned back to the South Platte River, the Applicant will need to account for any lagged dewatering depletions at the site. In addition, if it is determined by the Water Commissioneror Division Engineerthat the pit is not continuously dewatered at a relatively constant rate then the Applicant must track depletions and dewatering return flows in their accounting and replace any dewatering depletions that are not offset by dewatering return flows. Replacements Out-of-priority depletions associated with the mining operation at this site and alluvial well will be replaced using fully consumable municipal return flows leased from the City of Aurora ("Aurora"). The Applicant has entered into lease with Aurora signed December 9, 2021 and renewable through December 31, 2026. A copy of this lease has been provided by the applicant and is attached. Under the lease, water will be delivered to the outfall of the Robert W. Hite Treatment Facility (aka Metro Sewer, WDID 0200700) located on the South Platte River. The Hite Treatment Facility is located approximately 22 miles upstream of the Chavers Mine Resources site. The delivery schedule includes a transit loss of 0.5% per mile (11% for 22 miles) during the months of April through October and 0.25% per mile (5.5% for 22 miles) during the months of November through March. Conveyance loss for delivery of augmentation water to the South Platte River is subject to assessment and modification as determined by the Division Engineer. Any change-sto the assessed conveyance loss will be communicated to the Division 1 Call List via email. Aurora may alternatively deliver water at other points along a reach of the South Platte River beginning at or below the Hite Treatment Facility extending downstream to a point at or above the location where the South Platte crosses the south section line of the E '/z of the SW '/a of Section 18, Twp. 1 N, Rng. 66W, 6th P.M. The Applicant must notify the Water Commissioner at least 48 hours prior to making replacement deliveries at a location other than the Hite Treatment Facility. Under the lease, 38.16 acre-feet are scheduled to be delivered from the City of Aurora lease from August 1, 2024 through December 31, 2024 for the Chavers Mining Resource site, as shown on the attached Aurora Lease. The plan can be extended through July 31, 2025 if Applicant provides a copy of the lease extension with the City of Aurora to this office by November 1, 2024 that includes adequate replacement water to replace all un-replaced depletions, after accounting for any transit losses subject to Condition no. 1. Conditions of Approval This SWSP is hereby approved in accordance with section 37-90-137(11), C.R.S. subject to the following conditions: 1. This SWSP shall be valid for the period of August 1, 2024 through December 31, 2024, unless otherwise revoked, or superseded by decree. The plan will be extended until July 31, 2025 if Applicant provides