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Mining activities at the Beaz No. 3 Mine aze not expected to degrade the water quality of the North Fork of the Gunnison River. The disturbed azea for the Bear No. 3 Mine is about 8.4 acres in size, and is extremely small in comparison to the entire North Fork of the Gunnison River drainage basin. The small contribution of surface water runoff from the Bear disturbed azea will be diluted by flow in the North Fork of the Gunnison River. The Bear No. 3 sediment pond rarely dischazges, and any effluent is required to meet NPDES discharge standazds. The water quality of the North Fork of the Gunnison River is not expected to be impacted by water that infiltrates the alluvium of the Bear No. 3 facilities azea. The small contribution to the flow of the river is insignificant. Any water which enters the alluvium will be diluted by goundwater flowing through the alluvium. The groundwater flow through the alluvium will be further diluted by the greater flow in the North Fork of the Gunnison River. Flow in the river (at record low flow) is estimated to be nearly 130 times greater than the groundwater flow through the alluvium. As previously noted, a new spring has begun to flow from the vicinity of the Edwards Mine Portal This spring water is being diverted to the spring water treatment pond which, then, dischazges directly into the North Fork of the Gunnison River via a 4 inch flexible pipe. This discharge must meet all applicable water quality standazds. A renewal of the permit for this dischazge is pending with the Colorado Department of Public Health and Environment. The operator has included in the Probable Hydrologic Consequences section of the permit application an analysis of the hydrologic impact that this spring water would have on the water quality of the North Fork of the Gunnison River. Taking into account the flow and the total dissolved solids of the river, the spring and a hypothetical Beaz No. 3 Mine water discharge, the total dissolved solids of the river would increase from 140 mg/1 to 154 mg/1. Under these conditions, the impact of the spring water on the quality of the water of the North Fork of the Gunnison River is considered to be slight. 4. Conclusion An assessment of the probable hydrologic consequences of the mining operation and an assessment of the probable cumulative impact of all anticipated mining in the general area on the hydrologic balance has been made. This document entitled "Cumulative Hydrologic Impacts of Mining to the North Fork of the Gunnison River" is on file at the Division offices and may be reviewed during normal business hours. The document was updated in Permit Renewal No. 3 to incorporate additional anticipated impacts. No updates to the document were needed for Permit Renewal No. 4. Pursuant to Rule 2.07.6(2)(c), the Division finds that the Bear mining operation has been designed to minimize hydrologic impacts within the permit boundary, and to prevent material damage to the hydrologic balance outside the permit area. 22