Leon Kauffman
Leon Kauffman is a scientist working remotely with the New Jersey Water Science Center Integrated Hydrology Investigation Team
Science and Products
Filter Total Items: 25
Databases used to develop a hydrogeologic framework for Quaternary sediments in the glaciated conterminous United States Databases used to develop a hydrogeologic framework for Quaternary sediments in the glaciated conterminous United States
This dataset is a compilation of six databases described in Haj, A.E., Soller, D.R., Reddy, J.E., Kauffman, L.J., Yager, R.M., and Buchwald, C.A., 2018, Hydrogeologic framework for characterization and occurrence of confined and unconfined aquifers in quaternary sediments in the glaciated conterminous United States - A digital map compilation and database: U.S. Geological Survey Data...
Filter Total Items: 41
Combining particle-tracking and geochemical data to assess public supply well vulnerability to arsenic and uranium Combining particle-tracking and geochemical data to assess public supply well vulnerability to arsenic and uranium
Flow-model particle-tracking results and geochemical data from seven study areas across the United States were analyzed using three statistical methods to test the hypothesis that these variables can successfully be used to assess public supply well vulnerability to arsenic and uranium. Principal components analysis indicated that arsenic and uranium concentrations were associated with...
Authors
S.R. Hinkle, L. J. Kauffman, M.A. Thomas, C. J. Brown, K. A. McCarthy, S. M. Eberts, Michael R. Rosen, B. G. Katz
Simulations of ground-water flow and particle pathline analysis in the zone of contribution of a public-supply well in Modesto, eastern San Joaquin Valley, California Simulations of ground-water flow and particle pathline analysis in the zone of contribution of a public-supply well in Modesto, eastern San Joaquin Valley, California
Shallow ground water in the eastern San Joaquin Valley is affected by high nitrate and uranium concentrations and frequent detections of pesticides and volatile organic compounds (VOC), as a result of ground-water development and intensive agricultural and urban land use. A single public-supply well was selected for intensive study to evaluate the dominant processes affecting the...
Authors
Karen R. Burow, Bryant C. Jurgens, Leon J. Kauffman, Steven P. Phillips, Barbara A. Dalgish, Jennifer L. Shelton
Simulations of Ground-Water Flow, Transport, Age, and Particle Tracking near York, Nebraska, for a Study of Transport of Anthropogenic and Natural Contaminants (TANC) to Public-Supply Wells Simulations of Ground-Water Flow, Transport, Age, and Particle Tracking near York, Nebraska, for a Study of Transport of Anthropogenic and Natural Contaminants (TANC) to Public-Supply Wells
Contamination of public-supply wells has resulted in public-health threats and negative economic effects for communities that must treat contaminated water or find alternative water supplies. To investigate factors controlling vulnerability of public-supply wells to anthropogenic and natural contaminants using consistent and systematic data collected in a variety of principal aquifer...
Authors
Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Z. Hornberger
Limited occurrence of denitrification in four shallow aquifers in agricultural areas of the United States Limited occurrence of denitrification in four shallow aquifers in agricultural areas of the United States
The ability of natural attenuation to mitigate agricultural nitrate contamination in recharging aquifers was investigated in four important agricultural settings in the United States. The study used laboratory analyses, field measurements, and flow and transport modeling for monitoring well transects (0.5 to 2.5 km in length) in the San Joaquin watershed, California, the Elkhorn...
Authors
C.T. Green, L.J. Puckett, J.K. Böhlke, B.A. Bekins, S.P. Phillips, L. J. Kauffman, J. M. Denver, H.M. Johnson
Source and transport controls on the movement of nitrate to public supply wells in selected principal aquifers of the United States Source and transport controls on the movement of nitrate to public supply wells in selected principal aquifers of the United States
In 2003–2005, systematic studies in four contrasting hydrogeologic settings were undertaken to improve understanding of source and transport controls on nitrate movement to public supply wells (PSW) in principal aquifers of the United States. Chemical, isotopic, and age tracer data show that agricultural fertilizers and urban septic leachate were the primary sources of large nitrate...
Authors
P.B. McMahon, J.K. Böhlke, L. J. Kauffman, K.L. Kipp, M.K. Landon, C. A. Crandall, K.R. Burow, C. J. Brown
Simulated response of water quality in public supply wells to land use change Simulated response of water quality in public supply wells to land use change
Understanding how changes in land use affect water quality of public supply wells (PSW) is important because of the strong influence of land use on water quality, the rapid pace at which changes in land use are occurring in some parts of the world, and the large contribution of groundwater to the global water supply. In this study, groundwater flow models incorporating particle tracking...
Authors
P.B. McMahon, K.R. Burow, L. J. Kauffman, S. M. Eberts, J.K. Böhlke, J.J. Gurdak
Use of an integrated flow model to estimate ecologically relevant hydrologic characteristics at stream biomonitoring sites Use of an integrated flow model to estimate ecologically relevant hydrologic characteristics at stream biomonitoring sites
We developed an integrated hydroecological model to provide a comprehensive set of hydrologic variables representing five major components of the flow regime at 856 aquatic-invertebrate monitoring sites in New Jersey. The hydroecological model simulates streamflow by routing water that moves overland and through the subsurface from atmospheric delivery to the watershed outlet. Snow...
Authors
J.G. Kennen, L. J. Kauffman, M. A. Ayers, D.M. Wolock, Susan J. Colarullo
Mercury concentrations in water from an unconfined aquifer system, New Jersey coastal plain Mercury concentrations in water from an unconfined aquifer system, New Jersey coastal plain
Concentrations of total mercury (Hg) from 2 μg/L (the USEPA maximum contaminant level) to 72 μg/L in water from about 600 domestic wells in residential parts of eight counties in southern New Jersey have been reported by State and county agencies. The wells draw water from the areally extensive (7770 km2) unconfined Kirkwood–Cohansey aquifer system, in which background concentrations of...
Authors
J. L. Barringer, Zoltan Szabo, L. J. Kauffman, T. H. Barringer, P. E. Stackelberg, T. Ivahnenko, S. Rajagopalan, D. P. Krabbenhoft
Application of health-based screening levels to ground-water quality data in a state-scale pilot effort Application of health-based screening levels to ground-water quality data in a state-scale pilot effort
A state-scale pilot effort was conducted to evaluate a Health-Based Screening Level (HBSL) approach developed for communicating findings from the U.S. Geological Survey (USGS) National Water-Quality Assessment Program in a human-health context. Many aquifers sampled by USGS are used as drinking-water sources, and water-quality conditions historically have been assessed by comparing...
Authors
Patricia L. Toccalino, Julia E. Norman, Robyn H. Phillips, Leon J. Kauffman, Paul E. Stackelberg, Lisa H. Nowell, Sandra J. Krietzman, Gloria B. Post
Estimating spatial variability of recharge in southern New Jersey from unsaturated-zone measurements Estimating spatial variability of recharge in southern New Jersey from unsaturated-zone measurements
Spatial variability of recharge in southern New Jersey was studied by sampling the unsat-urated zone at 48 sites distributed over approximately 930 square kilometers. Samples of unsaturated-zone sediment were collected during the summer and fall of 1996. Unsaturated flow was calculated using moisture-content data and estimates of conductivity and matric potential derived from sediment...
Authors
Arthur L. Baehr, Leon J. Kauffman, Kimberlie Perkins, Bernard T. Nolan
Stochastic analysis of transverse dispersion in density‐coupled transport in aquifers Stochastic analysis of transverse dispersion in density‐coupled transport in aquifers
Spectral perturbation techniques have been used previously to derive integral expressions for dispersive mixing in concentration‐dependent transport in three‐dimensional, heterogeneous porous media, where fluid density and viscosity are functions of solute concentration. Whereas earlier work focused on evaluating longitudinal dispersivity in isotropic media and incorporating the result...
Authors
Claire Welty, Allen C. Kane, Leon J. Kauffman
Spatial variability of groundwater recharge and its effect on shallow groundwater quality in southern New Jersey Spatial variability of groundwater recharge and its effect on shallow groundwater quality in southern New Jersey
Point estimates of groundwater recharge at 48 sediment-coring locations vary substantially (−18.5–1840 cm yr−1) in a 930-km2 area of southern New Jersey. Darcian estimates of steady, long-term recharge made at depth in the unsaturated zone were estimated using pedotransfer functions of soil texture and interpolated (mapped) with nonparametric methods to assess aquifer vulnerability in...
Authors
Bernard T. Nolan, Arthur L. Baehr, Leon J. Kauffman
Science and Products
Filter Total Items: 25
Databases used to develop a hydrogeologic framework for Quaternary sediments in the glaciated conterminous United States Databases used to develop a hydrogeologic framework for Quaternary sediments in the glaciated conterminous United States
This dataset is a compilation of six databases described in Haj, A.E., Soller, D.R., Reddy, J.E., Kauffman, L.J., Yager, R.M., and Buchwald, C.A., 2018, Hydrogeologic framework for characterization and occurrence of confined and unconfined aquifers in quaternary sediments in the glaciated conterminous United States - A digital map compilation and database: U.S. Geological Survey Data...
Filter Total Items: 41
Combining particle-tracking and geochemical data to assess public supply well vulnerability to arsenic and uranium Combining particle-tracking and geochemical data to assess public supply well vulnerability to arsenic and uranium
Flow-model particle-tracking results and geochemical data from seven study areas across the United States were analyzed using three statistical methods to test the hypothesis that these variables can successfully be used to assess public supply well vulnerability to arsenic and uranium. Principal components analysis indicated that arsenic and uranium concentrations were associated with...
Authors
S.R. Hinkle, L. J. Kauffman, M.A. Thomas, C. J. Brown, K. A. McCarthy, S. M. Eberts, Michael R. Rosen, B. G. Katz
Simulations of ground-water flow and particle pathline analysis in the zone of contribution of a public-supply well in Modesto, eastern San Joaquin Valley, California Simulations of ground-water flow and particle pathline analysis in the zone of contribution of a public-supply well in Modesto, eastern San Joaquin Valley, California
Shallow ground water in the eastern San Joaquin Valley is affected by high nitrate and uranium concentrations and frequent detections of pesticides and volatile organic compounds (VOC), as a result of ground-water development and intensive agricultural and urban land use. A single public-supply well was selected for intensive study to evaluate the dominant processes affecting the...
Authors
Karen R. Burow, Bryant C. Jurgens, Leon J. Kauffman, Steven P. Phillips, Barbara A. Dalgish, Jennifer L. Shelton
Simulations of Ground-Water Flow, Transport, Age, and Particle Tracking near York, Nebraska, for a Study of Transport of Anthropogenic and Natural Contaminants (TANC) to Public-Supply Wells Simulations of Ground-Water Flow, Transport, Age, and Particle Tracking near York, Nebraska, for a Study of Transport of Anthropogenic and Natural Contaminants (TANC) to Public-Supply Wells
Contamination of public-supply wells has resulted in public-health threats and negative economic effects for communities that must treat contaminated water or find alternative water supplies. To investigate factors controlling vulnerability of public-supply wells to anthropogenic and natural contaminants using consistent and systematic data collected in a variety of principal aquifer...
Authors
Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Z. Hornberger
Limited occurrence of denitrification in four shallow aquifers in agricultural areas of the United States Limited occurrence of denitrification in four shallow aquifers in agricultural areas of the United States
The ability of natural attenuation to mitigate agricultural nitrate contamination in recharging aquifers was investigated in four important agricultural settings in the United States. The study used laboratory analyses, field measurements, and flow and transport modeling for monitoring well transects (0.5 to 2.5 km in length) in the San Joaquin watershed, California, the Elkhorn...
Authors
C.T. Green, L.J. Puckett, J.K. Böhlke, B.A. Bekins, S.P. Phillips, L. J. Kauffman, J. M. Denver, H.M. Johnson
Source and transport controls on the movement of nitrate to public supply wells in selected principal aquifers of the United States Source and transport controls on the movement of nitrate to public supply wells in selected principal aquifers of the United States
In 2003–2005, systematic studies in four contrasting hydrogeologic settings were undertaken to improve understanding of source and transport controls on nitrate movement to public supply wells (PSW) in principal aquifers of the United States. Chemical, isotopic, and age tracer data show that agricultural fertilizers and urban septic leachate were the primary sources of large nitrate...
Authors
P.B. McMahon, J.K. Böhlke, L. J. Kauffman, K.L. Kipp, M.K. Landon, C. A. Crandall, K.R. Burow, C. J. Brown
Simulated response of water quality in public supply wells to land use change Simulated response of water quality in public supply wells to land use change
Understanding how changes in land use affect water quality of public supply wells (PSW) is important because of the strong influence of land use on water quality, the rapid pace at which changes in land use are occurring in some parts of the world, and the large contribution of groundwater to the global water supply. In this study, groundwater flow models incorporating particle tracking...
Authors
P.B. McMahon, K.R. Burow, L. J. Kauffman, S. M. Eberts, J.K. Böhlke, J.J. Gurdak
Use of an integrated flow model to estimate ecologically relevant hydrologic characteristics at stream biomonitoring sites Use of an integrated flow model to estimate ecologically relevant hydrologic characteristics at stream biomonitoring sites
We developed an integrated hydroecological model to provide a comprehensive set of hydrologic variables representing five major components of the flow regime at 856 aquatic-invertebrate monitoring sites in New Jersey. The hydroecological model simulates streamflow by routing water that moves overland and through the subsurface from atmospheric delivery to the watershed outlet. Snow...
Authors
J.G. Kennen, L. J. Kauffman, M. A. Ayers, D.M. Wolock, Susan J. Colarullo
Mercury concentrations in water from an unconfined aquifer system, New Jersey coastal plain Mercury concentrations in water from an unconfined aquifer system, New Jersey coastal plain
Concentrations of total mercury (Hg) from 2 μg/L (the USEPA maximum contaminant level) to 72 μg/L in water from about 600 domestic wells in residential parts of eight counties in southern New Jersey have been reported by State and county agencies. The wells draw water from the areally extensive (7770 km2) unconfined Kirkwood–Cohansey aquifer system, in which background concentrations of...
Authors
J. L. Barringer, Zoltan Szabo, L. J. Kauffman, T. H. Barringer, P. E. Stackelberg, T. Ivahnenko, S. Rajagopalan, D. P. Krabbenhoft
Application of health-based screening levels to ground-water quality data in a state-scale pilot effort Application of health-based screening levels to ground-water quality data in a state-scale pilot effort
A state-scale pilot effort was conducted to evaluate a Health-Based Screening Level (HBSL) approach developed for communicating findings from the U.S. Geological Survey (USGS) National Water-Quality Assessment Program in a human-health context. Many aquifers sampled by USGS are used as drinking-water sources, and water-quality conditions historically have been assessed by comparing...
Authors
Patricia L. Toccalino, Julia E. Norman, Robyn H. Phillips, Leon J. Kauffman, Paul E. Stackelberg, Lisa H. Nowell, Sandra J. Krietzman, Gloria B. Post
Estimating spatial variability of recharge in southern New Jersey from unsaturated-zone measurements Estimating spatial variability of recharge in southern New Jersey from unsaturated-zone measurements
Spatial variability of recharge in southern New Jersey was studied by sampling the unsat-urated zone at 48 sites distributed over approximately 930 square kilometers. Samples of unsaturated-zone sediment were collected during the summer and fall of 1996. Unsaturated flow was calculated using moisture-content data and estimates of conductivity and matric potential derived from sediment...
Authors
Arthur L. Baehr, Leon J. Kauffman, Kimberlie Perkins, Bernard T. Nolan
Stochastic analysis of transverse dispersion in density‐coupled transport in aquifers Stochastic analysis of transverse dispersion in density‐coupled transport in aquifers
Spectral perturbation techniques have been used previously to derive integral expressions for dispersive mixing in concentration‐dependent transport in three‐dimensional, heterogeneous porous media, where fluid density and viscosity are functions of solute concentration. Whereas earlier work focused on evaluating longitudinal dispersivity in isotropic media and incorporating the result...
Authors
Claire Welty, Allen C. Kane, Leon J. Kauffman
Spatial variability of groundwater recharge and its effect on shallow groundwater quality in southern New Jersey Spatial variability of groundwater recharge and its effect on shallow groundwater quality in southern New Jersey
Point estimates of groundwater recharge at 48 sediment-coring locations vary substantially (−18.5–1840 cm yr−1) in a 930-km2 area of southern New Jersey. Darcian estimates of steady, long-term recharge made at depth in the unsaturated zone were estimated using pedotransfer functions of soil texture and interpolated (mapped) with nonparametric methods to assess aquifer vulnerability in...
Authors
Bernard T. Nolan, Arthur L. Baehr, Leon J. Kauffman