Research Objectives

Since 1986, the Upper Arkansas Toxic-Substances Hydrology Project has focused on metal transport in streams affected by mining. Our approach is to study chemical processes within a hydrologic context, using a two-step approach. First, we have employed instream experimentation to provide data about the processes affecting metals. Second, we have used the resulting data sets to develop and apply solute transport models that help quantify rates and processes. Tracer-injection studies in St. Kevin Gulch, near Leadville, Colorado, helped us design methods to characterize loadings from mining activities on a watershed scale. In 1995, we began to do tracer-injection studies in support of the planning needs of Federal Land Management Agencies, and as part of the U.S. Geological Survey's Abandonded Mine Land Initiative. The objectives are to:

1. Characterize the instream chemical processes that control the transport and transformation of metals downstream from mine drainage.

2. Use tracer-injection methods to evaluate remediation efforts in selected basins, in support of district efforts to apply the watershed approach to the remediation of abandoned mine lands.

3. Quantify the time and length scales of chemical and hydrologic processes that affect the metals through development of solute-transport models.

4. Characterize the chemistry of colloids, sediment, and bed sedments that are active in controlling the dissolved concentrations of metals.