There are more than 500,000 abandoned mines in the U.S., many having potential to pollute local water resources through groundwater interaction with surface waters. Understanding loading of metals from surface and shallow groundwater sources is expensive and technically complex.  Current monitoring tools often rely on limited sampling events that provide an incomplete snapshot of stream conditions during high and base flow conditions.

This project will continue field testing a high-resolution thermal monitoring technology that can identify critical reaches of surface streams where loading of metals occurs.  This approach will allow project teams to use a watershed approach in designing mitigation strategies for reducing mine impacts (i.e., targeting high loading locations for potential passive or active remediation). Project results will be shared with other EPA regions, states and tribes to improve abandoned-mine monitoring strategies and lower costs associated with mitigation projects.

Partners: Colorado Department of Public Health and the Environment