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Randall J Hunt, Ph.D.

Randall Hunt is a Chief Science Officer with the Upper Midwest Water Science Center.

AREAS OF EXPERTISE

My work focuses on water flow, and its effect on natural systems. This research uses a variety of approaches such as numerical modeling, ion and isotope chemistry, tracers, parameter estimation, and stochastic methods. It emphasizes a range of groundwater – surface water systems including wetland, stream, and lake interactions. More recently this work has been extended to research investigating ecohydrology of aquatic systems, effects of climate and landuse drivers, and source and transport of enteric viruses to drinking water wells and temperature through watersheds.  Much of my work has focused on improving model forecasts and uncertainty estimates  for decision making.

Professional Experience

  • 2018 to 2021 - Chief Science Officer, US Geological Survey, Upper Midwest Water Science Center

  • 2015 to 2018 - Associate Director of Science, US Geological Survey, Upper Midwest Water Science Center

  • 1996 to present - Research Hydrologist, US Geological Survey, Upper Midwest Water Science Center

  • 2003 to present - Adjunct Professor, University of Wisconsin-Madison, Department of Geoscience

  • 2000 to 2003 - Adjunct Assistant Professor, University of Wisconsin-Madison, Department of Geoscience

  • 1990 to 1996 - Hydrologist, US Geological Survey, Wisconsin District

  • 1991 to 1993 - Research Fellow, US DOE, Environmental Restoration and Waste Management Program

  • 1988 to 1990 - Hydrogeologist/Project Manager, Barr Engineering Company, Minneapolis, MN

  • 1986 to 1987 - Leopold Research Fellow, Leopold Memorial Reserve, Baraboo, WI

Education and Certifications

  • Ph.D in Hydrogeology (major) and Wetland Sciences (minor) - University of Wisconsin-Madison, 1993

  • M.S. in Hydrogeology - University of Wisconsin-Madison, 1987

  • B.A. in Geology (major) and Business (major) - Gustavus Adolphus College, 1985

Affiliations and Memberships*

  • Professional Societies

  • Professional Hydrologist #60-111, State of Wisconsin

  • Geological Society of America

  • American Water Resources Association, Wisconsin Section

  • Society of Wetland Scientists

  • American Geophysical Union

  • National Groundwater Association

  • Academic and Professional Service

  • 2014 to 2019 - Advisor to the Editor-In-Chief for the journal Groundwater

  • 2009 to 2013 - Associate Editor for Hydrogeology Journal

  • 2008 to 2009 - Guest Editor for "Hydrogeoecology and Groundwater Dependent Ecosystems" theme issue of Hydrogeology Journal

  • 2005 to present - Appointed by Governor to the State of Wisconsin Department of Regulation and Licensing Geology, Hydrology, Soil Science Joint Board (Chair 2008 - 2014)

  • 2005 to 2006 - Guest Editor for "Analytic Element Modeling" special issue of the journal Groundwater

  • 2002 to 2004 - Associate Editor for the journal Wetlands

  • 1998 to 2010 - Member, University of Wisconsin System Groundwater Research Advisory Council (Chair 2003-2010)

  • 1995 to present - Member, State of Wisconsin Groundwater Coordinating Council Research Subcommittee

  • 1997 to present - Associate Editor for the journal Groundwater

  • Editorial Boards

  • Groundwater

  • Environmental Modelling & Software

Honors and Awards

  • 2013 – Distinguished Service Award, Wisconsin Section-AWRA

  • 2012 – Superior Service Award, US Department of the Interior

Science and Products

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Colorado Basin Focus Area Study carousel

Integrated Water Availability Assessments (IWAAs)

The USGS Integrated Water Availability Assessments (IWAAs) are a multi-extent, stakeholder driven, near real-time census and prediction of water availability for both human and ecological uses at regional and national extents.
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Water Resources
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Integrated Water Availability Assessments (IWAAs)

The USGS Integrated Water Availability Assessments (IWAAs) are a multi-extent, stakeholder driven, near real-time census and prediction of water availability for both human and ecological uses at regional and national extents.
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Photos of TC Chamberlin Modeling Center computers and servers

TC Chamberlin Modeling Center

The TC Chamberlin Modeling Center provides one-stop access to advanced computing so no project is limited by a lack of computer power. The Center can provide hardware access, assistance with migration and implementation, and training. We also develop, test, and disseminate state-of-the-art computational and analytical techniques and tools so models can be more effectively used in decision-making.
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Upper Midwest Water Science Center
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TC Chamberlin Modeling Center

The TC Chamberlin Modeling Center provides one-stop access to advanced computing so no project is limited by a lack of computer power. The Center can provide hardware access, assistance with migration and implementation, and training. We also develop, test, and disseminate state-of-the-art computational and analytical techniques and tools so models can be more effectively used in decision-making.
Learn More
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Abstract cover art from PEST++ publication

PEST++: A Parameter ESTimation code optimized for large environmental models

The PEST++ software suite is object-oriented universal computer code written in C++ that expands on and extends the algorithms included in PEST, a widely used parameter estimation code written in Fortran. PEST++ is designed to lower the barriers of entry for users and developers while providing efficient algorithms that can accommodate large, highly parameterized problems.
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Upper Midwest Water Science Center
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PEST++: A Parameter ESTimation code optimized for large environmental models

The PEST++ software suite is object-oriented universal computer code written in C++ that expands on and extends the algorithms included in PEST, a widely used parameter estimation code written in Fortran. PEST++ is designed to lower the barriers of entry for users and developers while providing efficient algorithms that can accommodate large, highly parameterized problems.
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Abstract cover art for PESTCommander report cover

PESTCommander: A graphical user interface for file and run management across networks

PESTCommander is an object-oriented Graphical User Interface (GUI) written in Python® that facilitates the management of model files ("file management") and remote launching and termination of slave computers across a distributed network of computers ("run management").
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Upper Midwest Water Science Center
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PESTCommander: A graphical user interface for file and run management across networks

PESTCommander is an object-oriented Graphical User Interface (GUI) written in Python® that facilitates the management of model files ("file management") and remote launching and termination of slave computers across a distributed network of computers ("run management").
Learn More
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Abstract illustration representing GENIE

GENIE: A general model-independent TCP/IP run manager

GENIE is a model-independent suite of programs that can be used to generally distribute, manage, and execute multiple model runs via the TCP/IP infrastructure. The suite consists of a file distribution interface, a run manage, a run executer, and a routine that can be compiled as part of a program and used to exchange model runs with the run manager.
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Upper Midwest Water Science Center
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GENIE: A general model-independent TCP/IP run manager

GENIE is a model-independent suite of programs that can be used to generally distribute, manage, and execute multiple model runs via the TCP/IP infrastructure. The suite consists of a file distribution interface, a run manage, a run executer, and a routine that can be compiled as part of a program and used to exchange model runs with the run manager.
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Photograph of the Middle Allequash stream site in winter, 2003

Water, Energy, and Biogeochemical Budgets (WEBB): Trout Lake

USGS initiated the Water, Energy, and Biogeochemical Budgets (WEBB) program to understand the processes controlling water, energy, and biogeochemical fluxes over a range of temporal and spatial scales, and the effects of atmospheric and climatic variables. Trout Lake is one of five small, geographically and ecologically diverse watersheds representing a range of hydrologic and climatic conditions.
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Upper Midwest Water Science Center
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Water, Energy, and Biogeochemical Budgets (WEBB): Trout Lake

USGS initiated the Water, Energy, and Biogeochemical Budgets (WEBB) program to understand the processes controlling water, energy, and biogeochemical fluxes over a range of temporal and spatial scales, and the effects of atmospheric and climatic variables. Trout Lake is one of five small, geographically and ecologically diverse watersheds representing a range of hydrologic and climatic conditions.
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USGS science for a changing world logo

Hunting Invasive Species with HTCondor: High Throughput Computing for Big Data and Next Generation Sequencing

Large amounts of data are being generated that require hours, days, or even weeks to analyze using traditional computing resources. Innovative solutions must be implemented to analyze the data in a reasonable timeframe. The program HTCondor (https://research.cs.wisc.edu/htcondor/) takes advantage of the processing capacity of individual desktop computers and dedicated computing resources as a sing
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Community for Data Integration (CDI)
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Hunting Invasive Species with HTCondor: High Throughput Computing for Big Data and Next Generation Sequencing

Large amounts of data are being generated that require hours, days, or even weeks to analyze using traditional computing resources. Innovative solutions must be implemented to analyze the data in a reasonable timeframe. The program HTCondor (https://research.cs.wisc.edu/htcondor/) takes advantage of the processing capacity of individual desktop computers and dedicated computing resources as a sing
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Airborne Electromagnetic (AEM) Survey in Southwest and Southeast Areas, Wisconsin, 2022

Airborne electromagnetic (AEM) and magnetic survey data were collected during March 2022 over a distance of 2,574.6 line kilometers in southeast and southwest Wisconsin. These data were collected in support of an effort to improve estimates of depth to bedrock through a collaborative project between the U.S. Geological Survey (USGS), Wisconsin Department of Agriculture, Trade, and Consumer Protect
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Geology, Geophysics, and Geochemistry Science Center

MODFLOW-NWT simulations of regional groundwater flow under mining and pre-mining scenarios near the Mesabi Iron Range within the St. Louis River Basin, northeastern Minnesota

The U.S. Geological Survey developed two steady-state finite-difference regional groundwater-flow models using the MODFLOW-NWT computer code. These models simulate flow in the area of historical iron mining on and around the portion of the Mesabi Iron Range that is in the St. Louis River basin in northeastern Minnesota. The models are composed of 8 layers each; the upper four representing unconsol
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Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Parameter Estimation, Uncertainty Analysis, and Optimization with the PEST++ Family of codes: Tutorial Jupyter Notebooks

A series of Jupyter notebooks documenting a self-guided, interactive curriculum for the PEST++ family of software codes for uncertainty analysis, parameter estimation, and management optimization. For a currently maintained version of these materials, please visit https://github.com/gmdsi/GMDSI_notebooks.
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Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Airborne electromagnetic and magnetic survey data, northeast Wisconsin (ver. 1.1, June 2022)

Airborne electromagnetic (AEM) and magnetic survey data were collected during January and February 2021 over a distance of 3,170 line kilometers in northeast Wisconsin. These data were collected in support of an effort to improve estimates of depth to bedrock through a collaborative project between the U.S. Geological Survey (USGS), Wisconsin Department of Agriculture, Trade, and Consumer Protecti
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Geology, Geophysics, and Geochemistry Science Center

PEST++ Version 5.0 source code, pre-compiled binaries and example problem

PEST++ Version 5 software release. This release includes ASCII format C++11 source code, precompiled binaries for windows 10 and linux, and inputs files the example problem shown in the report
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Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center
Filter Total Items: 133

Can hydrological models benefit from using global soil moisture, evapotranspiration, and runoff products as calibration targets?

Hydrological models are usually calibrated to in-situ streamflow observations with reasonably long and uninterrupted records. This is challenging for poorly gage or ungaged basins where such information is not available. Even for gaged basins, the single-objective calibration to gaged streamflow cannot guarantee reliable forecasts because, as has been documented elsewhere, the inverse problem is m
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Water Resources, Nevada Water Science Center, Upper Midwest Water Science Center

Hydrologic change in the St. Louis River Basin from iron mining on the Mesabi Iron Range, northeastern Minnesota

This study compares the results of two regional steady-state U.S. Geological Survey Modular Three-Dimensional Finite-Difference Ground-Water Flow (MODFLOW) models constructed to quantify the hydrologic changes in the St. Louis River Basin from iron mining on the Mesabi Iron Range in northeastern Minnesota. The U.S. Geological Survey collaborated in this study with bands of the Minnesota Chippewa T
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Upper Midwest Water Science Center

Simulation of heat flow in a synthetic watershed: Lags and dampening across multiple pathways under a climate-forcing scenario

Although there is widespread agreement that future climates tend toward warming, the response of aquatic ecosystems to that warming is not well understood. This work, a continuation of companion research, explores the role of distinct watershed pathways in lagging and dampening climate-change signals. It subjects a synthetic flow and transport model to a 30-year warming signal based on climate pro
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Water Resources, Climate Research and Development Program, Nevada Water Science Center, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Comparison of radium analytical methods for municipal drinking water well operation

Radium (Ra) is a geogenic contaminant that occurs at high levels in the Midwestern Cambrian-Ordovician aquifer system (MCOAS), a regionally important sandstone and carbonate drinking water aquifer. Water utilities using the MCOAS often must adopt treatment methods or use alternative water sources to maintain high-quality drinking water. Here, we show that Ra in water obtained from a municipal well
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Water Resources, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Isotopic analysis of radium geochemistry at discrete intervals in the Midwestern Cambrian-Ordovician aquifer system

Radium (Ra) is a geogenic radioactive contaminant that frequently occurs at elevated levels in the Midwestern Cambrian-Ordovician aquifer system (MCOAS). Geochemical indicators (e.g., redox conditions or total dissolved solids) can broadly characterize conditions associated with elevated Ra levels in groundwater, but do not consistently correlate to elevated Ra within specific stratigraphic horizo
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Upper Midwest Water Science Center

NWTOPT — A hyperparameter optimization approach for selection of environmental model solver settings

Hyperparameter optimization approaches were applied to improve performance and accuracy of groundwater flow models. Freely available new software, NWTOPT, is described that uses Tree of Parzen Estimators (TPE) and Random Search algorithms to optimize MODFLOW-NWTs solver settings. We ran 3500 trials on a steady-state and transient model. To quantify the performance of candidate solver settings, we
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Upper Midwest Water Science Center

Use case development for earth monitoring, analysis, and prediction (EarthMAP)—A road map for future integrated predictive science at the U.S. Geological Survey

Executive SummaryThe U.S. Geological Survey (USGS) 21st-century science strategy 2020–30 promotes a bureau-wide strategy to develop and deliver an integrated, predictive science capability that works at the scales and timelines needed to inform societally relevant resource management and protection and public safety and environmental health decisions (U.S. Geological Survey, 2021). This is the ove
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Ecosystems, Water Resources, Upper Midwest Environmental Sciences Center, Western Geographic Science Center, Upper Midwest Water Science Center, California Water Science Center

A scalable model-independent iterative data assimilation tool for sequential and batch estimation of high dimensional model parameters and states

Ensemble-based data assimilation (DA) methods have displayed strong potential to improve model state and parameter estimation across several disciplines due to their computational efficiency, scalability, and ability to estimate uncertainty in the dynamic states and the parameters. However, a barrier to adoption of ensemble DA methods remains. Namely, there is currently a lack of available tools t
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Water Resources, California Water Science Center

Groundwater/surface-water interactions in the Partridge River Basin and evaluation of hypothetical future mine pits, Minnesota

The Partridge River Basin (PRB) covers 156 square miles in northeastern Minnesota with headwaters in the Mesabi Iron Range. The basin is characterized by extensive wetlands, lakes, and streams in poorly drained and often thin glacial material overlying Proterozoic bedrock. To better understand the interaction between these extensive surface water features and the groundwater system, a three-dimens
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Upper Midwest Water Science Center

Risk-based wellhead protection decision support: A repeatable workflow approach

Environmental water management often benefits from a risk-based approach where information on the area of interest is characterized, assembled, and incorporated into a decision model considering uncertainty. This includes prior information from literature, field measurements, professional interpretation, and data assimilation resulting in a decision tool with a posterior uncertainty assessment acc
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Water Resources, New York Water Science Center, Oregon Water Science Center, Upper Midwest Water Science Center

Sources and risk factors for nitrate and microbial contamination of private household wells in the fractured dolomite aquifer of northeastern Wisconsin

Background:Groundwater quality in the Silurian dolomite aquifer in northeastern Wisconsin, USA, has become contentious as dairy farms and exurban development expand.Objectives:We investigated private household wells in the region, determining the extent, sources, and risk factors of nitrate and microbial contamination.Methods:Total coliforms, Escherichia coli, and nitrate were evaluated by synopti
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Upper Midwest Water Science Center, Laboratory for Infectious Disease and the Environment

Evaluating lower computational burden approaches for calibration of large environmental models

Realistic environmental models used for decision making typically require a highly parameterized approach. Calibration of such models is computationally intensive because widely used parameter estimation approaches require individual forward runs for each parameter adjusted. These runs construct a parameter-to-observation sensitivity, or Jacobian, matrix used to develop candidate parameter upgrade
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Upper Midwest Water Science Center

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.

NWTOPT

Hyperparameter optimization approaches were applied to improve performance and accuracy of groundwater flow models. Freely available new software, NWTOPT, is described that uses Tree of Parzen Estimators (TPE) and Random Search optimization algorithms to optimize MODFLOW-NWT’s solver settings. We ran 3500 trials on a steady-state and transient model. To quantify the p
By
Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

PESTCommander

PESTCommander is an object-oriented Graphical User Interface (GUI) written in Python® that facilitates the management of model files ("file management") and remote launching and termination of slave computers across a distributed network of computers ("run management").

By
Upper Midwest Water Science Center

GENIE Version 2: A general model-independent TCP/IP run manager

GENIE Version 2 is a model-independent suite of programs that can be used to generally distribute, manage, and execute multiple model runs via a TCP/IP network. The suite consists of a file distribution interface, a run manager, a run executer, and a routine that can be compiled as part of a program and used to exchange model runs with the run manager.

By
Upper Midwest Water Science Center

Science and Products

*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