eNews September 2019

Meet the Researcher: Kenneth C. Carroll, Associate Professor, New Mexico State University

By Carolina Mijares, NM WRRI Program Manager

Associate Professor Dr. Kenneth C. Carroll began his career at New Mexico State University (NMSU) in March 2013, as an Assistant Professor of Geohydrology and Environmental Science in the Water Science & Management Graduate Degree Program and Department of Plant & Environmental Sciences. Prior to this appointment, he held a research scientist position with the Environmental Systems Group at the Pacific Northwest National Laboratory (PNNL). At PNNL he supported subsurface contamination cleanup efforts at the Department of Energy (DOE) Hanford Site, which included applied research for technology development and feasibility/treatability assessments. He supported the development of mass flux measurement and analysis for assessing contamination remediation, which lead to a framework for determining remediation closure criteria for soil vapor extraction. He also conducted research that involved numerical-modeling code comparisons for CO2 sequestration, including both trapping mechanisms and geomechanics for CO2 leakage risk analysis. Dr. Carroll and collaborators invented and developed novel methods to increase production of enhanced geothermal energy.

Before joining PNNL in 2010, Carroll worked in industry gaining hydrology and geochemistry consulting experience focused on some of the largest metal mines located in Australia, Argentina, Chile, Indonesia, Iran, Mexico, and the United States. Additionally, he completed a postdoctoral appointment at the University of Arizona where he investigated subsurface heterogeneity impacts on groundwater remediation performance.

Dr. Carroll obtained his PhD in 2007 in Hydrology and Water Resources and a minor in Soil, Water, and Environmental Science from the University of Arizona; he recieved his MS in 1999 in Aqueous/Environmental Geochemistry from Ohio University. Some of Dr. Carroll’s research interests include advancing our understanding of water supply and water quality in arid regions; the development of innovative water resources, environmental-remediation, carbon-capture, energy production alternatives, and the development of novel approaches for characterization of contamination natural attenuation and active-remediation enhancement.

Since joining the Department of Plant & Environmental Sciences at NMSU, Dr. Carroll has been supporting the environmental and soil science focus areas of the department. His teaching and research background and interests cover a broad range of areas that pertain to the coupling of hydrobiogeochemical processes that mediate exchange of water and chemicals between the hydrosphere, lithosphere, and biosphere. He has been developing field, laboratory, and simulation approaches for evaluating the influence of human activities on chemical cycling in environmental systems. He utilizes a multidisciplinary approach to both research and teaching, which he believes is important for understanding complex issues and coupled processes in the environment.

The NMSU University Research Council awarded Dr. Carroll the Early Career Award in 2013 for exceptional achievements in creative scholarly activity. He was also presented with the Patricia Christmore Faculty Teaching Award for superb junior faculty excellence in teaching at NMSU. Dr. Carroll received outstanding reviewer status for Journal of Contaminant Hydrology; he is the associate editor for three journals (Journal of Hydrology X, Journal of Hydrology, and Journal of Contaminant Hydrology). Dr. Carroll published a hydrogeology textbook; was Elected Chair for the Groundwater Technical Committee of American Geophysical Union Hydrology Section; and became the C. Herb Ward Family Endowed Interdisciplinary Chair in Environmental and Water Science. As PI and co-PI, Dr. Carroll has directed research projects greater than $3 million (in addition to greater than $1 million while at PNNL prior to 2013) funded from DOE, DOD, NASA, USDA, BoR, USGS, state of NM, and NM WRRI.

Dr. Carroll recently received two $300,000 grants from the DOE to work with national laboratories to characterize the migration of contaminants within surface water and groundwater to advance our understanding of how water flow and contaminant transport affects our ecosystems. One of the grants is in collaboration with researchers at the Oak Ridge National Laboratory focusing on the clean-up of legacy mercury that was accidentally released while helping to develop nuclear weaponry and isotopes for energy production. Carroll’s group is characterizing surface water/groundwater exchange hydrology, which supports the contamination clean-up efforts. The other new grant is in collaboration with researchers at the PNNL to help clean-up the contamination in the subsurface of the Hanford Site located in Washington State. Carroll’s group is looking at the processes that naturally decrease concentrations, and then enhance those processes in the subsurface to speed-up the clean-up.

Dr. Carroll and his team have also been conducting research at NMSU in the development of innovative water resources funded by Bureau of Reclamation (BoR). Part of this program included an Evaluation of Source Water, Extraction Potential, and Potential Impacts of Using Brackish Water for Desalination in New Mexico, which was funded by BoR and the USDA Southwest Hub for Risk Adaptation and Mitigation to Climate Change.

In 2018, Dr. Carroll received a two-year grant through the NMSU and BoR Cooperative Agreement, which is administered by the NM WRRI. He and his NMSU research colleagues, Pei Xu, Phil King, and Brian Hurd, are working on a project entitled, Isotopic, Geochemical, and Modeling Evaluation of Source Water, Extraction Potential, and Potential Impacts of Using Brackish Water for Desalination in the Mesilla Basin, NM. The research objective is to characterize the fresh and brackish groundwater system in the Mesilla Basin, and assess the impact of brackish production for desalination on fresh water sustainability.

For the Transboundary Aquifer Assessment Program (with USGS and NM WRRI), Carroll’s group developed a dissolved gas sampling device enabling noble gas isotopic age dating of groundwater to evaluate recharge and water use sustainability. They have similarly compared isotopic signatures in the groundwater to analogous isotopic signatures in the aquifer minerals to characterize the dissolution of evaporite minerals as a major source of salinity in groundwater, which is being considered as a source of water for a proposed new desalination plant. When the project is completed, a final report will be posted on the NM WRRI website.