Model Development

Draining mine tunnels contribute metals and acidity to streams throughout the western United States. One remediation strategy that is increasing in usage is the emplacement of hydraulic bulkheads to impound water within the subsurface. Potential secondary effects of bulkhead usage are difficult to quantify however because of the inherent complexity of most mountain hydrologic systems. In...

The area surrounding Manitou Springs, Colorado is host to numerous bedrock springs, which help to support the local economy through tourist visitation. Although many springs previously flowed directly to the surface, most of the “springs” in the area are now more strictly classified as flowing artesian wells completed in the Manitou Formation, a cavernous intermixed limestone and dolomite, which...

OTEQ is a mathematical simulation model used to characterize the fate and transport of waterborne solutes in streams and rivers. The model is formed by coupling a solute transport model with a chemical equilibrium submodel. The solute transport model is based on OTIS, a model that considers the physical processes of advection, dispersion, lateral inflow, and transient storage. The equilibrium...

OTIS is a mathematical simulation model used to characterize the fate and transport of water-borne solutes in streams and rivers. The governing equation underlying the model is the advection-dispersion equation with additional terms to account for transient storage, lateral inflow, first-order decay, and sorption. This equation and the associated equations describing transient storage and sorption...

MODFLOW is the USGS's modular hydrologic model. MODFLOW is considered an international standard for simulating and predicting groundwater conditions and groundwater/surface-water interactions. Originally developed and released solely as a groundwater-flow simulation code when first published in 1984, MODFLOW's modular structure has provided a robust framework for integration of additional...