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on approximately 2.76 acres of exposed groundwater area from the dewatering trenches and <br /> settling basin, 10.84 acres of exposed surface area for the recharge ponds, and a net evaporative <br /> loss of approximately 2.57 feet per year. If the moisture content of the material transported off- <br /> site is assumed to be 4 percent by weight, the annual mined product is estimated to be 90,000 <br /> tons per year, then the annual amount of water lost in product is approximately 4.77 acre-feet. It <br /> is also estimated that approximately 0.8 acre-feet of water will be needed annually for dust <br /> control during mining and reclamation activities. A new SWSP, as referenced above, for <br /> evaporation and operational losses has been submitted to the SEO for 2024. <br /> Connell Resources, Inc. maintains a Substitute Water Supply Plan (SWSP) for the replacement <br /> of stream depletions associated with mining operations through the State Engineers Office <br /> (SEO). The Timnath Connell Pit also has an active well permit (see Exhibit C-5, Water Resource <br /> Map). Water use in the Timnath Connell Pit includes dust control as well as offsetting <br /> evaporative losses from recharge ponds, dewatering trenches, and the drainage sump. <br /> Groundwater flows can also be affected by dewatering operations at the site as well as removing <br /> irrigated farmland from cultivation creating lagged depletions from the Cache la Poudre River <br /> alluvial aquifer. Replacement of depletions at the site will continue to be made via delivery of <br /> leased Box Elder Ditch Company shares to on-site recharge ponds. <br /> Potential Mining Impacts <br /> As discussed above, the mining operation is continuing only in Phase 3. The reclamation plan <br /> continues to include open water in the two unlined groundwater recharge ponds. The mine area <br /> reclamation plan also includes construction of a lined, below-grade reservoir suitable for water <br /> storage. Final construction of water storage infrastructure and filling of the below-grade <br /> reservoir will be completed by the property owner after mining reclamation has been accepted <br /> and released. <br /> Potential Reclamation Impacts <br /> Once mining and reclamation are complete and dewatering pumps are turned off, potential <br /> impacts to surrounding wells from mine dewatering will cease. Potential impacts to the adjacent <br /> groundwater table from recharge pond evaporative losses will remain, but should not negatively <br /> affect adjacent properties or wells. For the recharge pond surface area, evaporative losses will be <br /> accounted for with a permanent augmentation plan. <br /> Groundwater Monitoring Plan <br /> A groundwater monitoring and reporting plan has been operational during the life of the mine. <br /> Piezometers at several locations on and near the site allow depth to groundwater measurements <br /> providing trends in seasonal groundwater elevation relative to water surface elevations in the <br /> CYO ponds. <br /> Timnath Connell Pit <br /> DRMS 112 Permit Amendment Application Page 18 <br />