Carole Johnson is a hydrologist with the Hydrogeophysics Branch of the USGS Water Resources Mission Area Earth System Processes Division. Carole provides leadership to USGS hydrologists nationally on development and application of hydrogeophysical methods to groundwater studies through applied research, training, and policy development.
Carole Johnson is a hydrologist with the USGS Earth System Processes Division, Hydrogeophysics Branch in Storrs, Connecticut, where she provides leadership to USGS hydrologists nationally on development and application of hydrogeophysical methods to USGS groundwater studies through applied research, training, and policy development. Carole’s research interests include use of borehole- and surface-geophysical methods and hydraulic testing for characterization of fractured-rock aquifers. She has coauthored ~40 USGS publications on use of hydrogeophysical methods for aquifer characterization for water resources and contaminant investigations. An experienced trainer, Carole has taught numerous webinars and more than 20 hands-on workshops for scientists on geophysical field methods, data processing, and data analysis for groundwater investigations, including through USGS courses, U.S. Environmental Protection Agency, National Groundwater Association Fractured Rock Conference workshops, and classes for licensed environmental professionals in New Jersey and around New England.
Carole currently holds a professional geologists license in New Hampshire, and serves on the board of the Environmental and Engineering Geophysics Society. Carole has a B.S. in geology from Bates College and M.S. in hydrology from the University of New Hampshire.
Science and Products
Spectral gamma borehole geophysical methods measure natural-gamma energy spectra, which are caused by the decay of uranium, thorium, potassium-40, and anthropogenic radioactive isotopes. Spectral gamma data can be used to identify and quantify the amount of uranium, thorium, and potassium-40 isotopes detected in boreholes.
Evaluating long-term patterns of decreasing groundwater discharge through a lake-bottom permeable reactive barrier
Identifying and quantifying groundwater exchange is critical when considering contaminant fate and transport at the groundwater/surface-water interface. In this paper, areally distributed temperature and point seepage measurements are used to efficiently assess spatial and temporal groundwater discharge patterns through a glacial-kettle lakebed...McCobb, Timothy D.; Briggs, Martin A.; LeBlanc, Denis R.; Day-Lewis, Frederick D.; Johnson, Carole D.
Hydraulic tomography: 3D hydraulic conductivity and fracture network connectivity in a contaminated mudstone aquifer
No abstract available.Barrash, Warren; Tiedeman, Claire; Thrash, Colby; Patterson, Jeremy; Johnson, Carole D.
Bioremediation in fractured rock: 1. Modeling to inform design, monitoring, and expectations
Field characterization of a trichloroethene (TCE) source area in fractured mudstones produced a detailed understanding of the geology, contaminant distribution in fractures and the rock matrix, and hydraulic and transport properties. Groundwater flow and chemical transport modeling that synthesized the field characterization information proved...Tiedeman, Claire; Shapiro, Allen M.; Hsieh, Paul A.; Imbrigiotta, Thomas; Goode, Daniel J.; Lacombe, Pierre; DeFlaun, Mary F.; Drew, Scott R.; Johnson, Carole D.; Williams, John H.; Curtis, Gary P.
Application of frequency- and time-domain electromagnetic surveys to characterize hydrostratigraphy and landfill construction at the Amargosa Desert Research Site, Beatty, Nevada
In 2014 and 2015, the U.S. Geological Survey (USGS), conducted frequency-domain electromagnetic (FDEM) surveys at the USGS Amargosa Desert Research Site (ADRS), approximately 17 kilometers (km) south of Beatty, Nevada. The FDEM surveys were conducted within and adjacent to a closed low-level radioactive waste disposal site located at the ADRS....White, Eric A.; Day-Lewis, Frederick D.; Johnson, Carole D.; Lane, John W.
Statistical comparison of methods for estimating sediment thickness from Horizontal-to-Vertical Spectral Ratio (HVSR) seismic methods: An example from Tylerville, Connecticut, USA
Determining sediment thickness and delineating bedrock topography are important for assessing groundwater availability and characterizing contamination sites. In recent years, the horizontal-to-vertical spectral ratio (HVSR) seismic method has emerged as a non-invasive, cost-effective approach for estimating the thickness of unconsolidated...Johnson, Carole D.; Lane, John W.
Characterization of fractures and flow zones in a contaminated crystalline-rock aquifer in the Tylerville section of Haddam, Connecticut
The U.S. Geological Survey, in cooperation with the Connecticut Department of Energy and Environmental Protection, investigated the characteristics of the bedrock aquifer in the Tylerville section of Haddam, Connecticut, from June to August 2014. As part of this investigation, geophysical logs were collected from six water-supply wells and were...Johnson, Carole D.; Kiel, Kristal F.; Joesten, Peter K.; Pappas, Katherine L.
Imaging pathways in fractured rock using three-dimensional electrical resistivity tomography
Major challenges exist in delineating bedrock fracture zones because these cause abrupt changes in geological and hydrogeological properties over small distances. Borehole observations cannot sufficiently capture heterogeneity in these systems. Geophysical techniques offer the potential to image properties and processes in between boreholes. We...Robinson, Judith; Slater, Lee; Johnson, Timothy B.; Shapiro, Allen M.; Tiedeman, Claire; Ntlargiannis, Dimitrios; Johnson, Carole D.; Day-Lewis, Frederick D.; Lacombe, Pierre; Imbrigiotta, Thomas; Lane, John W.
Flow and sorption controls of groundwater arsenic in individual boreholes from bedrock aquifers in central Maine, USA
To understand the hydrogeochemical processes regulating well water arsenic (As) evolution in fractured bedrock aquifers, three domestic wells with [As] up to 478 μg/L are investigated in central Maine. Geophysical logging reveals that fractures near the borehole bottom contribute 70-100% of flow. Borehole and fracture water samples from various...Yang, Qiang; Culbertson, Charles W.; Nielsen, Martha G.; Schalk, Charles W.; Johnson, Carole D.; Marvinney, Robert G.; Stute, Martin; Zheng, Yan
A small-diameter NMR logging tool for groundwater investigations
A small-diameter nuclear magnetic resonance (NMR) logging tool has been developed and field tested at various sites in the United States and Australia. A novel design approach has produced relatively inexpensive, small-diameter probes that can be run in open or PVC-cased boreholes as small as 2 inches in diameter. The complete system, including...Walsh, David; Turner, Peter; Grunewald, Elliot; Zhang, Hong; Butler, James J.; Reboulet, Ed; Knobbe, Steve; Christy, Tom; Lane, John W.; Johnson, Carole D.; Munday, Tim; Fitzpatrick, Andrew
Physical, chemical, and isotopic data from groundwater in the watershed of Mirror Lake, and in the vicinity of Hubbard Brook, near West Thornton, New Hampshire, 1983 to 1997
Research on the hydrogeologic setting of Mirror Lake near West Thornton, New Hampshire (43° 56.5’ N, 71° 41.5’ W), includes the study of the physical, chemical, and isotopic characteristics of groundwater in the vicinity of the lake and nearby Hubbard Brook. Presented here are those physical, chemical, and isotopic data for the period 1983 to 1997...LaBaugh, James W.; Harte, Philip T.; Shapiro, Allen M.; Hsieh, Paul A.; Johnson, Carole D.; Goode, Daniel J.; Wood, Warren W.; Buso, Donald C.; Likens, Gene E.; Winter, Thomas C.
Well network installation and hydrogeologic data collection, Assateague Island National Seashore, Worcester County, Maryland, 2010
The U.S. Geological Survey, as part of its Climate and Land Use Change Research and Development Program, is conducting a multi-year investigation to assess potential impacts on the natural resources of Assateague Island National Seashore, Maryland that may result from changes in the hydrologic system in response to projected sea-level rise. As...Banks, William S.L.; Masterson, John P.; Johnson, Carole D.
Spatially variable stage-driven groundwater-surface water interaction inferred from time-frequency analysis of distributed temperature sensing data
Characterization of groundwater-surface water exchange is essential for improving understanding of contaminant transport between aquifers and rivers. Fiber-optic distributed temperature sensing (FODTS) provides rich spatiotemporal datasets for quantitative and qualitative analysis of groundwater-surface water exchange. We demonstrate how time-...Mwakanyamale, Kisa; Slater, Lee; Day-Lewis, Frederick D.; Elwaseif, Mehrez; Johnson, Carole D.