Historic regional mining in the upper watershed for over a 100 years beginning in the 1860’s left remanent fluvial mill tailing deposits within the floodplain of the San Miguel River. Much of the tailings had been cleaned up as part of as part of a 1992 Consent Decree through the Colorado Department of Health and Human Environment (CDPHE). The Town of Telluride in coordination with the CDPHE embarked on an ambitious project to remediate one of the last remaining deposits referred to as Society Turn Tailings Pile #1. The presence tailings, with elevated heavy metal concentrations, as River sediment and bank material was a significant cause of degrading water quality, creating poor conditions for aquatic life and is a direct threat to public exposure. Furthermore, negative impacts to surrounding riparian and terrestrial habitat is obvious by the large, bare, unvegetated areas of land in the project area. ERC worked with the Town and CDPHE to develop a plan that focused on stabilizing the tailings on site, away from the river and public contact, while maintaining a natural character and the ecological integrity of the Valley Floor. The project consisted of removal of tailings and placement of approximately 21,500 CYDs into consolidation areas, capping approximately 13.6 acres of in-place exposed tailings and consolidated tailing, approximately 4,754 feet of new channel realignment away from tailings, backfill of the abandon approximately 3,446 feet river channel to create natural riparian landform and floodplain buffer for the tailings and native revegetation of over 30 acres of disturbed lands. ERC delivered the project utilizing a turn-key design-build model, providing initial concept development, cost estimates, construction plans complete regulatory permitting, construction implementation and a three-year regulatory monitoring program. All construction activities and revegetation was completed within a five month period. Two years following project completion, remediation goals have proved successful.
