All One River GIS

There is an underground drainage tunnel in the Leadville historical mining district, Lake County, Colorado that has been determined to be in a state of immediate threat of flooding. This situation is due to obstruction by collapsed material over time and subsequent damming of both mine discharge and ground water. This obstruction has formed a debris dam of ponded water estimated to be one billion gallons and its failure could result in catastrophic consequences that have prompted Lake County officials to declare a state of emergency.

If this unstructured dam fails without a controlled release, a subsequent flood could result in destruction of residences and potentially contaminate the headwaters of the Arkansas River with untreated water, part of which is derived from mine drainage. This situation is being monitored by the US Bureau of Reclamation and local county governments. However, if the effluent discharge contaminates the river then the impact will be disastrous not only for the environment, habitat and community of that region, but a discharge of untreated water into the river system will also adversely impact Colorado Mining – an industry that is currently under review and attack from a growing anti-mining forum in the state.

The dam is a result of collapsed material in an underground tunnel, which was constructed by the Bureau of Mines to provide drainage of seepage from some of the underground mine workings. The US Department of Reclamation acquired responsibility for the tunnel in 1959 with the intent of including the drainage water as part of the supply for the Frying Pan-Arkansas Project – river drainage systems used for recreation and water supply. The water contained metals, which discharged into the East Fork of the Arkansas. To bring the discharge into compliance with the Clean Water Act, a water treatment plant was constructed in March of 1992. However, this plant is not engineered to accommodate the conditions of flooding that seem to be immanent.

Local media are portraying this situation in an electrifying manner on the real basis of potentially life-threatening flooding.

Recently, the Geological Society of America presented an academic analysis by geologist, Michael Holmes, from the E.P.A. of same tunnel and addressed the alarming state of this structure:

“Data from the mine pool from the past decade show ominous rising ground-water levels and suggest that the efficiency of the drainage tunnel is declining. ” — HOLMES, Michael, U.S.EPA Region VIII, 999 18th Street, Suite 500, Denver, CO 80202, holmes.michael@epa.gov

The potential for catastrophic flooding is definitely a threat albeit not as alarming as the Vail Daily purports as a, “pool of contaminated water trapped by the collapse in the Leadville Mine Drainage Tunnel,” and, “toxic acid and metal-laden water.” Rather, the nature of the water is currently being diluted by the natural spring and run-off. “This catchment is at an altitude of more than 3,000 - 4300 meters a.s.l. and thus contains a significant portion of snow and ice that, until this summer, was essentially perennial.” — Michael Holmes. (For general information on ground water and hardrock mining: http://gsa.confex.com/gsa/2002AM/finalprogram/session_2770.htm)  Though the toxicity is likely not as lethal as the Vail Daily infers, the volume is a definite and serious threat.

“Ground seepage from increased snow levels is adding further pressure on the blockage,” said Polly White of the Colorado Division of Emergency Management.”

The threat of catastrophic flooding in this situation is very real. Failure of the underground dam threatens not only to flood the vicinity of Leadville but also contaminate the Arkansas River, which would be a terrible environmental disaster that you can bet the public will hold the mining industry liable though the mining industry neither built the tunnel, nor manages it. The tunnel is a Bureau of Reclamation project and their staff is addressing this situation, apparently under accusations by local community of waiting too long.