This fall, the U.S. Department of Energy (DOE) Office of Legacy Management (LM) completed a reclamation project to protect the Dolores River by addressing sedimentation issues near the historic Burro Mines Complex in San Miguel County, Colorado. The Burro Mines Complex was operational periodically between 1948 and the 1980s.

Burro Tunnel Mine

View of the Burro Tunnel Mine after reclamation of the waste-rock pile and revetment along Burro Canyon Creek.

The project addressed waste-rock piles associated with three uranium mines in the Burro Mines Complex: the Burro Tunnel Mine, the Burro No. 3 Mine, and the Burro No. 5 Mine. The Burro Tunnel Mine borders the east side of County Road S8, adjacent to the Dolores River. 

In 2007, an LM staff member witnessed a storm hitting the Burro Mines Complex, washing away 4 inches of county road pavement into the river. In 2014, a 30-minute storm produced a downpour of rain and quarter-sized hail, creating an extreme wall of water that washed sediment into the river.

LM staff knew something had to be done to protect the river from future storms. LM explored possible remedies and evaluated their potential impact on the local environment

Because the proposed reclamation activities were considered a federal action, in June of 2019, LM prepared an Environmental Assessment (EA) under the National Environmental Policy Act (NEPA). The EA was made available for public review and comment in August 2020

LM had a limited window to complete the project before desert bighorn sheep wintering and lambing season began in December. Crews hauled away 72,117 cubic yards of waste rock and improved existing erosion-control features and constructed new ones, including sediment basins and stream armoring. The reclamation work was completed ahead of schedule in October.

Deborah Barr, LM’s Uranium Leasing Program manager, was pleased that work was completed at the reclamation site, ahead of schedule and ahead of wildlife restrictions.

“The Burro Mine Complex reclamation project has successfully met LM’s goal of protecting the river and was conducted safely -- a win for the environment, LM, local communities, and all the collaborative agencies involved in the reclamation project,” she said.

Collaboration was a key element of this reclamation project. LM worked with several federal, state, and local agencies in addressing the potential impacts to the environment, the community, and cultural resources.

In addition to the public, LM engaged with the Bureau of Land Management (BLM); the Colorado Division of Reclamation, Mining, and Safety (CDRMS); the Colorado State Historic Preservation Office (SHPO); and San Miguel County. 

LM closely coordinated with SHPO to preserve historical uranium mining features. Many historic uranium mines have been fully reclaimed; however, many features at the Burro Mines Complex were maintained to preserve certain aspects of its historical integrity.

Learn more about the Uranium Leasing Program.