Eastern Mineral and Environmental Resources Science Center
In order to predict the potential impact of a mineral deposit or a mine site on the environmental health of a watershed, it is necessary to consider the manner in which metals are transported through the watershed. Groundwater typically composes a large fraction of stream flow, and therefore can be a principal pathway by which metals are introduced to the stream ecosystem. Because metals can be liberated by water-rock interactions within the ground-water system (particularly in the shallow seasonally saturated zone), the groundwater may exert a primary control upon both the rate and distribution of metals released to the near-surface environment in a watershed. A successful model of the potential watershed-scale environmental consequences of mining specific mineral deposits therefore probably must have a ground-water component.
A host of model types could conceivably be used to relate groundwater parameters (and factors controlling them) to stream metal loads. These range from detailed, site-specific numerical flow and transport models (based on first principals of physics and chemistry) to simple statistical "black-box" models based on emperical relationships. The central focus of this subtask's work will therefore be to evaluate these different models types and determine which type might be most appropriate as a plug-in for the transport module in the watershed-scale MEA toolbox. The most feasible model to use probably will be some form of a statistical model. However, no such models currently exist that specifically relate watershed ground-water characteristics to surface-water metal concentrations. Work on this subtask consisted of developing such a statistical model.
Ultimately, the objective of this subtaskwas to develop a plug-in (or series of plug-ins)for the transport module in the watershed-scale MEA toolbox that helps predict surface water metal concentrations given the characterisitics of the ground-water system in the watershed.
Task is no longer active.
|Mineral Resources Program||National Minerals Information / Geology, Minerals, Energy and Geophysics|
|Alaska / Crustal Geophysics and Geochemistry / Central Mineral and Environmental Resources / Spatial Data|