A hiker’s report of “orange-colored” water flowing from an abandoned mine into the South Fork of the West Mancos River on Monday triggered an investigation by the Colorado Division of Reclamation Mining and Safety.
The mine drainage in upper Owen Basin of the La Plata Mountains was not a spill or acute release, according to DRMS.
An investigation by a DRMS mine specialist concluded the hiker saw “a perennial discharge from a mine that has likely been occurring since the mine closed over 100 years ago,” said Chris Arend, communications director for the Colorado Department of Natural Resources.
The hiker, Marty Stecher of Mancos, saw water flowing from the mine portal last week, then again Monday.
The water flowed into the South Fork of the West Mancos River between Hesperus and Spiller Peak in eastern Montezuma County.
“What caught my attention last week was that upstream of the mine, the river looked pristine. But downstream, the creek bed had a buildup of an orange-colored deposit,” Stecher said.
The DMRS staff member met with Stecher and got near to the discharge site, Arend said. No mine waste was visible in the creek a few miles downstream of the mine, but an estimated 5 to 10 gallons were discharging per minute.
Upon further investigation, and after reviewing Stecher’s photos and descriptive location, it was determined the draining mine water has been occurring over some time and was not a “spill” or acute release.
“Colorado has thousands of ‘prelaw’ mines across the state, and the DRMS Inactive Mines program is diligently working through remediation at these mines each year,” Arend said.
An analysis of abandoned mines in Rush Basin, southwest of Owen Basin, was completed recently, a DRMS official said.
An abandoned mine, or prelaw mine, as defined by the Surface Mine Control and Reclamation Act, ceased operation before 1977 and has no responsible party.
It was unclear how much the mine has affected water quality or if it’s also from the surrounding geology. It is listed as an underground mine on the DRMS GIS map.
It is not uncommon for old mines to “burp up” mineral-laden orange water, state mine officials said.
Stecher reached out to The Journal and The Durango Herald about his concerns.
“It is concerning to see because the Mancos River is used by the public. We drink that water, use it on farms,” Stecher said.
When contacted Monday, DRMS said it was not aware of a mine discharge site at that location, and sent a mine specialist based in Durango to investigate Monday afternoon.
Stecher has come across other discolored bodies of water on his forays into the backcountry. Last year, two beaver ponds near the Mancos River had a distinct blue hue.
“To me that does not look right either,” he said, adding that the ponds have since become clearer.
If members of the public see a discharge from a mine, they are asked contact DRMS at (303) 866-3567 or email firstname.lastname@example.org. For more background, see DRMS’ Inactive Mine Reclamations website at: https://bit.ly/3ievC13