EPA Research Partner Support Story: Identifying locations of metals loading to surface waters from active and abandoned mines
Partners: Colorado Department of Public Health and Environment, Utah Department of Environmental Quality, Utah Geological Survey, and the Ute Mountain Ute Tribe in Utah.
Challenge: Identifying locations of metals loading to surface water from impacted mine pools, groundwater, and surface water
Resource: High resolution temperature and conductivity sensor networks along key stream sections, in collaboration with the U.S. Geological Survey (USGS)
Project Period: 2018 – Present
More than 500,000 abandoned mines found in the U.S.—particularly in western states—present risks to surface water, groundwater, and human and ecological health due to the volume and toxic nature of the waste produced at these sites. They also present challenges to those tasked with addressing related public health risks and leading environmental cleanup efforts, primarily EPA, states and tribes. Mining sites make up a significant portion of the national Superfund site portfolio in these states.
Mine drainage refers to any surface water or groundwater that drains from an active or abandoned mining operation. The impact of such drainage on water quality can range from minimal, leaving it similar to a natural state, to severely degraded. Polluted mine drainage can be extremely acidic and often consists of high concentrations of toxic, heavy metals. The more acidic the water, the more likely it is to be harmful to living organisms. Measuring the ecosystem health of surrounding surface water has historically involved limited sampling, providing only a snapshot of conditions that can quickly change.
EPA ORD, in collaboration with EPA Region 8 (Mountains and Plains), and with help from other partners, deployed a dense network of sensors that provide accurate water quality measurements on a continual basis. USGS provided equipment and assisted with deployment, data collection and interpretation using fiber optic distributed temperature sensing.
"With data and monitoring available through the sensor network, we have been better able to understand mine drainage across sites and make informed decisions about where to conduct remediation or additional analysis." – Colorado Department of Public Health and Environment, Remedial Project Manager Mark Rudolph
Colorado Department of Public Health and Environment, other state partners and remedial project managers were able to share results of specific sites, lessons learned, and provide additional support using these technologies. Best practices were captured and shared with key partners to improve strategies and lower costs associated with these mitigation efforts.
EPA researchers and their partners are now applying what they learned from developing and deploying the sensor networks to update conceptual site models and advance the understanding of the interactions of mine pools, shallow groundwater, and surface water, even across large, diverse mining districts. This work is helping managers better target mine sites for high resolution site characterization and optimize remediation system design an operation, significantly reducing costs to federal, state and tribal partners. Data sets and successful deployments have resulted in using these and similar technologies at other mining sites in Colorado including Colorado Smelter, Nelson Tunnel and Standard Mine Superfund Sites.