You are here:
Simulating the Fate and Transport of an Acid Mine Drainage Release
Citation:
Knightes, Chris, Kate Sullivan, B. Avant, Mike Cyterski, J. Washington, AND L. Prieto. Simulating the Fate and Transport of an Acid Mine Drainage Release. 2016 AGU Fall Meeting, CA, San Francisco, December 12 - 16, 2016.
Impact/Purpose:
Presented at 2016 AGU Fall Meeting.
Description:
On August 5, 2015, approximately 3 million gallons of acid mine drainage were released from the Gold King Mine into Cement Creek in the San Juan River watershed (CO, NM, UT). The release further mobilized additional metals, which resulted in a large mass of solids and dissolved metals entering Cement Creek. These metals were released into the Animas River. As the release acidity was neutralized, the metals precipitated and formed the visually noticeable “yellow boy,” which flowed down the San Juan River. We applied the Water Quality Analysis Simulation Program (WASP) using empirically based parameterization to simulate and describe the movement of the plume and total and dissolved concentrations of all metals, including Arsenic, Copper, Lead, and Zinc. We estimated that the plume took between approximately 1 to 3 days to pass any given location. The peak concentration of the plume took 1.5 days to reach Durango, CO, 2.9 days to reach Farmington, NM, and 5.8 days to reach Mexican Hat, UT. Total metal concentration decreased rapidly going downstream, dropping 80% upon entering the Animas at Silverton, CO (16 rkms), and 99.5% entering the San Juan at Farmington (190 rkms). Metal concentrations decreased by dilution, settling, and dispersion. Modeling suggests that deposition occurred primarily in the upper Animas River near Silverton and near Durango, which was supported with empirical evidence. This work demonstrates the utility of a combined empirical and mechanistic modeling analysis. We additionally investigate long-term residual effects and potential exposure concentrations during storm and snowmelt high flow periods after the visible plume had traversed the system.
