Randall J Hunt, Ph.D. (Former Employee)
Science and Products
Filter Total Items: 150
Estimating recharge rates with analytic element models and parameter estimation Estimating recharge rates with analytic element models and parameter estimation
Quantifying the spatial and temporal distribution of recharge is usually a prerequisite for effective ground water flow modeling. In this study, an analytic element (AE) code (GFLOW) was used with a nonlinear parameter estimation code (UCODE) to quantify the spatial and temporal distribution of recharge using measured base flows as calibration targets. The ease and flexibility of AE...
Authors
W. R. Dripps, R. J. Hunt, Marilyn P. Anderson
Speciation and transport of newly deposited mercury in a boreal forest wetland: A stable mercury isotope approach Speciation and transport of newly deposited mercury in a boreal forest wetland: A stable mercury isotope approach
As part of the Mercury Experiment to Assess Atmospheric Loadings in Canada and the United States (METAALICUS) the fate and transport of contemporary mercury (Hg) deposition in a boreal wetland was investigated using an experimentally applied stable mercury isotope. We applied high purity (99.2% ± 0.1) 202Hg(II) to a wetland plot to determine if (1) the 202Hg was detectable above the pool...
Authors
B.A. Branfireun, D. P. Krabbenhoft, H. Hintelmann, R. J. Hunt, J.P. Hurley, J.W.M. Rudd
Investigating surface water-well interaction using stable isotope ratios of water Investigating surface water-well interaction using stable isotope ratios of water
Because surface water can be a source of undesirable water quality in a drinking water well, an understanding of the amount of surface water and its travel time to the well is needed to assess a well's vulnerability. Stable isotope ratios of oxygen in river water at the City of La Crosse, Wisconsin, show peak-to-peak seasonal variation greater than 4‰ in 2001 and 2002. This seasonal...
Authors
R. J. Hunt, T.B. Coplen, N.L. Haas, D. A. Saad, M. A. Borchardt
Simulation of ground-water flow, surface-water flow, and a deep sewer tunnel system in the Menomonee Valley, Milwaukee, Wisconsin Simulation of ground-water flow, surface-water flow, and a deep sewer tunnel system in the Menomonee Valley, Milwaukee, Wisconsin
Numerical models were constructed for simulation of ground-water flow in the Menomonee Valley Brownfield, in Milwaukee, Wisconsin. An understanding of ground-water flow is necessary to develop an efficient program to sample ground water for contaminants. Models were constructed in a stepwise fashion, beginning with a regional, single-layer, analytic-element model (GFLOW code) that...
Authors
C. P. Dunning, D. T. Feinstein, R. J. Hunt, J. T. Krohelski
Improving wetland simulations by including heat transport in groundwater flow modeling Improving wetland simulations by including heat transport in groundwater flow modeling
A procedure was developed to automatically calibrate a groundwater flow and heat transport model, resulting in the estimation of hydraulic conductivity and flux across the water table in wetland systems. This paper describes differences between previous approaches and this study, and summarizes some challenges in the method implementation. The procedure was validated in a sequence of...
Authors
Hector R. Bravo, F. Jiang, R. J. Hunt
Vulnerability of drinking-water wells in La Crosse, Wisconsin, to enteric-virus contamination from surface water contributions Vulnerability of drinking-water wells in La Crosse, Wisconsin, to enteric-virus contamination from surface water contributions
Human enteric viruses can contaminate municipal drinking-water wells, but few studies have examined the routes by which viruses enter these wells. In the present study, the objective was to monitor the municipal wells of La Crosse, Wisconsin, for enteric viruses and determine whether the amount of Mississippi River water infiltrating the wells was related to the frequency of virus...
Authors
M. A. Borchardt, N.L. Haas, R. J. Hunt
Non-USGS Publications**
Abrams, D.B., Haitjema, H.M., Feinstein, D.T. and Hunt, R.J., 2015, Field test of a Hybrid Finite-Difference and Analytic Element regional model. Groundwater. doi: 10.1111/gwat.12319.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 150
Estimating recharge rates with analytic element models and parameter estimation Estimating recharge rates with analytic element models and parameter estimation
Quantifying the spatial and temporal distribution of recharge is usually a prerequisite for effective ground water flow modeling. In this study, an analytic element (AE) code (GFLOW) was used with a nonlinear parameter estimation code (UCODE) to quantify the spatial and temporal distribution of recharge using measured base flows as calibration targets. The ease and flexibility of AE...
Authors
W. R. Dripps, R. J. Hunt, Marilyn P. Anderson
Speciation and transport of newly deposited mercury in a boreal forest wetland: A stable mercury isotope approach Speciation and transport of newly deposited mercury in a boreal forest wetland: A stable mercury isotope approach
As part of the Mercury Experiment to Assess Atmospheric Loadings in Canada and the United States (METAALICUS) the fate and transport of contemporary mercury (Hg) deposition in a boreal wetland was investigated using an experimentally applied stable mercury isotope. We applied high purity (99.2% ± 0.1) 202Hg(II) to a wetland plot to determine if (1) the 202Hg was detectable above the pool...
Authors
B.A. Branfireun, D. P. Krabbenhoft, H. Hintelmann, R. J. Hunt, J.P. Hurley, J.W.M. Rudd
Investigating surface water-well interaction using stable isotope ratios of water Investigating surface water-well interaction using stable isotope ratios of water
Because surface water can be a source of undesirable water quality in a drinking water well, an understanding of the amount of surface water and its travel time to the well is needed to assess a well's vulnerability. Stable isotope ratios of oxygen in river water at the City of La Crosse, Wisconsin, show peak-to-peak seasonal variation greater than 4‰ in 2001 and 2002. This seasonal...
Authors
R. J. Hunt, T.B. Coplen, N.L. Haas, D. A. Saad, M. A. Borchardt
Simulation of ground-water flow, surface-water flow, and a deep sewer tunnel system in the Menomonee Valley, Milwaukee, Wisconsin Simulation of ground-water flow, surface-water flow, and a deep sewer tunnel system in the Menomonee Valley, Milwaukee, Wisconsin
Numerical models were constructed for simulation of ground-water flow in the Menomonee Valley Brownfield, in Milwaukee, Wisconsin. An understanding of ground-water flow is necessary to develop an efficient program to sample ground water for contaminants. Models were constructed in a stepwise fashion, beginning with a regional, single-layer, analytic-element model (GFLOW code) that...
Authors
C. P. Dunning, D. T. Feinstein, R. J. Hunt, J. T. Krohelski
Improving wetland simulations by including heat transport in groundwater flow modeling Improving wetland simulations by including heat transport in groundwater flow modeling
A procedure was developed to automatically calibrate a groundwater flow and heat transport model, resulting in the estimation of hydraulic conductivity and flux across the water table in wetland systems. This paper describes differences between previous approaches and this study, and summarizes some challenges in the method implementation. The procedure was validated in a sequence of...
Authors
Hector R. Bravo, F. Jiang, R. J. Hunt
Vulnerability of drinking-water wells in La Crosse, Wisconsin, to enteric-virus contamination from surface water contributions Vulnerability of drinking-water wells in La Crosse, Wisconsin, to enteric-virus contamination from surface water contributions
Human enteric viruses can contaminate municipal drinking-water wells, but few studies have examined the routes by which viruses enter these wells. In the present study, the objective was to monitor the municipal wells of La Crosse, Wisconsin, for enteric viruses and determine whether the amount of Mississippi River water infiltrating the wells was related to the frequency of virus...
Authors
M. A. Borchardt, N.L. Haas, R. J. Hunt
Non-USGS Publications**
Abrams, D.B., Haitjema, H.M., Feinstein, D.T. and Hunt, R.J., 2015, Field test of a Hybrid Finite-Difference and Analytic Element regional model. Groundwater. doi: 10.1111/gwat.12319.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government