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Andrew J Long

Andy Long has more than 25 years of experience assessing groundwater flow and transport through numerical modeling, analyzing ambient and injected tracers, and geophysical methods.

Professional Experience

  • Groundwater Specialist, USGS Washington Water Science Center (July 2015 – present) - I advise and train staff scientists and technicians on technical issues, including interpretive studies and the collection, management, and archival of data. I advise managers of the science center in building and guiding the overall groundwater studies and data programs. I conduct scientific investigations involv

  • Chair and Vice Chair, Washington Hydrogeology Symposium (2017 – present) –

  • Research Hydrologist, USGS Dakota Water Science Center (DWSC; 2009 – 2015) –

    Developed innovative methods to better understand, quantify, and test hypotheses related to groundwater flow and transport in karst aquifers. Topics include groundwater age dating, lumped-parameter models, aquifer classification, hydrochemical evaluation, heat transport, and groundwater recharge.

  • Adjunct Assistant Professor, South Dakota School of Mines and Technology (SDSMT; Oct 2005 – 2018) –

    Served on eight graduate advisory committees for M.S. and Ph.D. students and gave numerous guest lectures.

  • Hydrologist, USGS DWSC (Jan 1999 – Oct 2009) –

    This involved numerical modeling of groundwater flow and solute transport, dye tracing experiments in karst aquifers, aquifer pumping tests, and development of new research models.

  • Consultant (1994–1998) –

    Conducted GIS analysis and groundwater modeling with MODFLOW related to a proposed low-level nuclear-waste site for the Boyd County Monitoring Committee in Nebraska. Consulted for Terra Nitrogen in Sergeant Bluff, Iowa and simulated groundwater flow and transport with MODFLOW, MOC, and GIS analysis to assess the movement of ammonia contamination.

  • Research assistant, SDSMT (1995–1998) –

    Developed and wrote the FORTRAN computer code for a three-dimensional groundwater model to simulate dual-porosity flow in karst aquifers. Collaborated with a team of researchers on the design of a numerical model to simulate surface-water and groundwater flow, dynamically linked to atmospheric processes.

  • Hydrologist, Rapid City Water Department (1994-1995) –

    Collaborated with the USGS to simulated groundwater flow in karst aquifers.

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