The Question: Should the remains of the Eugenia Mine on the slopes of Longs Peak be cleaned up to reduce the runoff of heavy metals?
In the 19th century, prospectors looked for valuable minerals in the area now known as Rocky Mountain National Park. The Eugenia mine was active in the 1800s but was ultimately not successful. The mine shaft has been sealed since the 1960s. Mine tailings remain near the entrance of the mine and may be leaching harmful compounds into groundwater.
The Project: Analyze rock samples from waste piles with XRF to determine the concentration of heavy metals.
Investigators led by David Rathke, Ph.D., and Richard Graham, Ph.D., from the U.S. Environmental Protection Agency, Region 8, along with John Burghardt from the Geologic Resources Division of the National Park Service examined the Engenia Mine and surrounding drainages to determine whether heavy metals were present and were being mobilized into local waterways. They sieved waste rock and tailings samples, and they analyzed them with x-ray fl orescence to determine the elemental composition of the samples. They collected water and soil from downgradient drainages to determine whether heavy metals were being mobilized from the mine tailings.