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. . WATER QUALITY, SURFACE AND GROUND (includes a fmding on Standard 5) Affected Environment: The Proposed Action ties directly into the Arkansas River and, in this area, the river is classified as: Aquatic life cold 1, Recreation 1, Water Supply, and Agricultural. It is contained on the Colorado 303( d) list as being water quality impaired due to Zn and is a high priority. The zinc contamination is due to past mining activities upstream near Leadville and great strides have been made in recent years in cleaning up waterways near Leadville. Other heavy metals are known to exist in the river in the area, including Mercury, mobilized when the river bed is disturbed. Environmental Consequences/Mitigation: The Proposed Action would have an effect on both the uplands around the river and the river channel itself. In the uplands, the development of the trails and the increase in use on the banks would lead to increased runoff because of the surface disturbance. This increase in runoff would consequently increase sediment loads in the river. Within the river channel, work would take place that would disturb the bed. The disturbance of the river bed in this area would mainly produce a short term increase in the amount of sediment in the water column; however, some Mercury could get into the water column as work is being done in the channel. Monitoring of suction dredging activities by the BLM and Army Corps of Engineers nearby has shown that very little heavy metal, including Mercury, gets into the water through bed disturbance. In general, the Proposed Action would have little effect on water quality. In order for this project to get approval from other agencies, the proponent would need to get a Phase II, Storm Water Discharge permit from the State of Colorado, and a 404 Permit from the Army Corps of Engineers. These two permits, along with the design of the proposal, result in the Proposed Action having very little impact on water quality in the area. The No Action Alternative would result in no changes to either the uplands or the river channel. This would result in water quality conditions staying the same as they currently are. Finding on the Public Land Health Standard for Water Quality: Currently, the waters in the area are meeting BLM standards except for zinc from upstream historic mining. The implementation ofthe Proposed Action would have no effect on the Public Land Health Standard for Water Quality. WILDERNESS, AREAS OF CRITICAL ENVIRONMENTAL CONCERN, WILD AND SCENIC RIVERS Affected Environment: None of these special designations are found in the project area. Environmental Consequences/Mitigation: No impacts. NON-CRITICAL ELEMENTS The following elements must be addressed due to the involvement of Standards for Public Land Health: