2025-07-21_HYDROLOGY - M2008082 (2)

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Morton Lakes Substitute Water Supply Plan Renewal (Amended) July 21, 2025 Page 7 of 17 In addition to the evaporation, water is lost with the mined product removed from the mine sites as shown in attached Table 2. Under the current approved SWSP, gravel production was anticipated to be completed in the first half of 2025, with an anticipated production of 550,000 tons. Brannan now projects that they will mine approximately 450,000 additional tons of gravel in 2025 from Stages 5, 7A, and 7B within the lined pits for this amended plan period, which will result in a depletion of 2% by weight. The water lost from mined product for this amended plan period is projected to total 6.49 acre-feet as shown in Table 2, Column 4. Dust Suppression The estimated water used for dust suppression for this amended plan period is 6.50 acre- feet, as shown in Table 2, Column 5. Brannan will pump water from Stage 2 for dust suppression purposes during this plan period. Dewatering Minimal dewatering will occur in Stages 5, 613, 6D, 7A, and 7B from within the lined pits and such water is returned directly to the stream. Dewatering will occur at this site at a relatively constant rate until the end of the SWSP period. All dewatering will be accurately metered so as to properly determine the lagged dewatering depletions to the stream that will result once dewatering ceases. As long as all water is pumped from within the lined pits and is returned to the stream without consumptive use, there are no new lagged depletions from dewatering that need to be replaced under this SWSP for Stages 5, 613, 6D, 7A, and 7B. Dewatering of unlined Stages 1 and 2 will also occur during the final reclamation and backfilling of those stages that is anticipated to occur in December 2025. The consumption resulting from the "first fill" of Stages 1 and 2 have previously been accounted for, according to the Applicant.