Mining activity within Montezuma Canyon is believed to have begun in the early 17th century. Although CORO was closed to mining in 1976, 63 abandoned mine shafts, adits, and test pits remain within the park and water resources are impacted by the legacy mining effects. There are seventeen ephemeral and perennial springs – many of whose sources are near remnant mines. Additional water sources in the park exist as flooded adits and mineshafts, or as water troughs supplied with mine water through a pipe system.

The National Park Service Resource Management Division is performing investigations and feasibility studies to develop effective remediation actions for the mine-adjacent springs within CORO. A comprehensive understanding of the hydro-geochemistry must be developed to define the nature and extent of contamination to water resources from legacy mining activity. An up-to-date water and sediment sample assessment is needed to prioritize treatment areas and then implement the best remediation treatment.

The primary objectives of this investigation are to:

• Characterize the current spatial and temporal components for the presence of metals and trace elements in CORO’s water resources;
• Use geochemical techniques to increase the understanding of the sources, pathways, and ages of water resources; and
• Conduct a preliminary assessment of possible bioaccumulation of metals and trace elements in aquatic organisms.