Brian Andraski (Former Employee)
Science and Products
Filter Total Items: 50
Plant-based plume-scale mapping of tritium contamination in desert soils
Plant-based techniques were tested for field-scale evaluation of tritium contamination adjacent to a low-level radioactive waste (LLRW) facility in the Amargosa Desert, Nevada. Objectives were to (i) characterize and map the spatial variability of tritium in plant water, (ii) develop empirical relations to predict and map subsurface contamination from plant-water concentrations, and (iii) gain ins
Authors
Brian J. Andraski, David A. Stonestrom, R. L. Michel, K. J. Halford, J.C. Radyk
Modeling tritium transport through a deep unsaturated zone in an arid environment
Understanding transport of tritium (3H) in unsaturated zones is critical to evaluating options for waste isolation. Tritium typically is a large component of low-level radioactive waste (LLRW). Studies at the U.S. Geological Survey's Amargosa Desert Research Site (ADRS) in Nevada investigate 3H transport from a closed LLRW facility. Two boreholes are 100 and 160 m from the nearest waste trench and
Authors
C.J. Mayers, Brian J. Andraski, C.A. Cooper, S.W. Wheatcraft, David A. Stonestrom, R. L. Michel
Constraining the inferred paleohydrologic evolution of a deep unsaturated zone in the Amargosa Desert
Natural flow regimes in deep unsaturated zones of arid interfluvial environments are rarely in hydraulic equilibrium with near-surface boundary conditions imposed by present-day plant–soil–atmosphere dynamics. Nevertheless, assessments of water resources and contaminant transport require realistic estimates of gas, water, and solute fluxes under past, present, and projected conditions. Multimillen
Authors
Michelle Ann Walvoord, David A. Stonestrom, Brian J. Andraski, Robert G. Striegl
Monitoring radionuclide contamination in the unsaturated zone - Lessons learned at the Amargosa Desert Research Site, Nye County, Nevada
Contaminant-transport processes are being investigated at the U.S. Geological Survey’s Amargosa Desert Research Site (A DRS), adjacent to the Nation’s first commercial disposal facility for low-level radioactive waste. Gases containing tritium and radiocarbon are migrating through a 110-m thick unsaturated zone from unlined trenches that received waste from 1962 to 1992. Results relevant to long-
Authors
David A. Stonestrom, Jared D. Abraham, Brian J. Andraski, Ronald J. Baker, C. Justin Mayers, Robert L. Michel, David E. Prudic, Robert G. Striegl, Michelle Ann Walvoord
Plume-scale testing of a simplified method for detecting tritium contamination in plants and soil
Cost-effective methods are needed to detect contamination near radioactive-waste and other contaminated sites. Such methods should be capable of providing an early warning of contaminant releases and should be accurate and robust enough for assessing the long-term performance of waste-isolation facilities and remediation measures. Recently, a simplified method for detecting tritium contamination i
Authors
Brian J. Andraski, Keith J. Halford, Robert L. Michel
Variations in flow and transport in thick desert vadose zones in response to paleoclimatic forcing (0-90 kyr): Field measurements, modeling, and uncertainties
An understanding of unsaturated flow and potential recharge in interdrainage semiarid and arid regions is critical for quantification of water resources and contaminant transport. We evaluated system response to paleoclimatic forcing using water potential and Cl profiles and modeling of nonisothermal liquid and vapor flow and Cl transport at semiarid (High Plains, Texas) and arid (Chihuahuan Deser
Authors
Bridget R. Scanlon, K. Keese, R.C. Reedy, Jirka Šimůnek, Brian J. Andraski
Simplified method for detecting tritium contamination in plants and soil
Cost-effective methods are needed to identify the presence and distribution of tritium near radioactive waste disposal and other contaminated sites. The objectives of this study were to (i) develop a simplified sample preparation method for determining tritium contamination in plants and (ii) determine if plant data could be used as an indicator of soil contamination. The method entailed collectio
Authors
Brian J. Andraski, Mark W. Sandstrom, R. L. Michel, J.C. Radyk, David A. Stonestrom, M. J. Johnson, C.J. Mayers
Thermocouple psychrometry
Thermocouple psychrometry is a technique that infers the water potential of the liquid phase of a sample from measurements within the vapor phase that is in equilibrium with the sample. The theoretical relation between water potential of the liquid phase and relative humidity of the vapor phase is given by the Kelvin equation Ψ = energy/volume = (RT/Vw) ln(p/po) [3.2.3–1]where ψ is water potential
Authors
Brian J. Andraski, Bridget R. Scanlon
Selected micrometeorological and soil-moisture data at Amargosa Desert Research Site in Nye County near Beatty, Nevada, 1998-2000
Selected micrometeorological and soil-moisture data were collected at the Amargosa Desert Research Site adjacent to a low-level radioactive waste and hazardous chemical waste facility near Beatty, Nev., 1998-2000. Data were collected in support of ongoing research studies to improve the understanding of hydrologic and contaminant-transport processes in arid environments.
Micrometeorological da
Authors
Michael J. Johnson, Charles J. Mayers, Brian J. Andraski
Miscellaneous methods for measuring matric or water potential
A variety of techniques to measure matric potential or water potential in the laboratory and in the field are described in this section. The techniques described herein require equilibration of some medium whose matric or water potential can be determined from previous calibration or can be measured directly. Under equilibrium conditions the matric or water potential of the medium is equal to that
Authors
Bridget R. Scanlon, Brian J. Andraski, Jim Bilskie
Testing a full‐range soil‐water retention function in modeling water potential and temperature
Recent work has emphasized development of full‐range water‐retention functions that are applicable under both wet and dry soil conditions, but evaluation of such functions in numerical modeling has been limited. Here we show that simulations using the Rossi‐Nimmo (RN) full‐range function compared favorably with those using the common Brooks‐Corey function and that the RN function can improve predi
Authors
Brian J. Andraski, Elizabeth A. Jacobson
Tritium in water vapor in the shallow unsaturated zone at the Amargosa Desert Research Site
Samples of water vapor in soil gas were obtained at the U.S. Geological Survey's Amargosa Desert Research Site in 1997 and 1998 from a depth of 1.5 m (meters) within a 300 m by 300 m grid that lies immediately to the south and west of a low-level radioactive-waste disposal site. The gas samples were analyzed for tritium. Fifty-eight samples were collected in May 1997; 61 samples were collected in
Authors
Richard W. Healy, Robert G. Striegl, Robert L. Michel, David E. Prudic, Brian J. Andraski
Science and Products
Filter Total Items: 50
Plant-based plume-scale mapping of tritium contamination in desert soils
Plant-based techniques were tested for field-scale evaluation of tritium contamination adjacent to a low-level radioactive waste (LLRW) facility in the Amargosa Desert, Nevada. Objectives were to (i) characterize and map the spatial variability of tritium in plant water, (ii) develop empirical relations to predict and map subsurface contamination from plant-water concentrations, and (iii) gain ins
Authors
Brian J. Andraski, David A. Stonestrom, R. L. Michel, K. J. Halford, J.C. Radyk
Modeling tritium transport through a deep unsaturated zone in an arid environment
Understanding transport of tritium (3H) in unsaturated zones is critical to evaluating options for waste isolation. Tritium typically is a large component of low-level radioactive waste (LLRW). Studies at the U.S. Geological Survey's Amargosa Desert Research Site (ADRS) in Nevada investigate 3H transport from a closed LLRW facility. Two boreholes are 100 and 160 m from the nearest waste trench and
Authors
C.J. Mayers, Brian J. Andraski, C.A. Cooper, S.W. Wheatcraft, David A. Stonestrom, R. L. Michel
Constraining the inferred paleohydrologic evolution of a deep unsaturated zone in the Amargosa Desert
Natural flow regimes in deep unsaturated zones of arid interfluvial environments are rarely in hydraulic equilibrium with near-surface boundary conditions imposed by present-day plant–soil–atmosphere dynamics. Nevertheless, assessments of water resources and contaminant transport require realistic estimates of gas, water, and solute fluxes under past, present, and projected conditions. Multimillen
Authors
Michelle Ann Walvoord, David A. Stonestrom, Brian J. Andraski, Robert G. Striegl
Monitoring radionuclide contamination in the unsaturated zone - Lessons learned at the Amargosa Desert Research Site, Nye County, Nevada
Contaminant-transport processes are being investigated at the U.S. Geological Survey’s Amargosa Desert Research Site (A DRS), adjacent to the Nation’s first commercial disposal facility for low-level radioactive waste. Gases containing tritium and radiocarbon are migrating through a 110-m thick unsaturated zone from unlined trenches that received waste from 1962 to 1992. Results relevant to long-
Authors
David A. Stonestrom, Jared D. Abraham, Brian J. Andraski, Ronald J. Baker, C. Justin Mayers, Robert L. Michel, David E. Prudic, Robert G. Striegl, Michelle Ann Walvoord
Plume-scale testing of a simplified method for detecting tritium contamination in plants and soil
Cost-effective methods are needed to detect contamination near radioactive-waste and other contaminated sites. Such methods should be capable of providing an early warning of contaminant releases and should be accurate and robust enough for assessing the long-term performance of waste-isolation facilities and remediation measures. Recently, a simplified method for detecting tritium contamination i
Authors
Brian J. Andraski, Keith J. Halford, Robert L. Michel
Variations in flow and transport in thick desert vadose zones in response to paleoclimatic forcing (0-90 kyr): Field measurements, modeling, and uncertainties
An understanding of unsaturated flow and potential recharge in interdrainage semiarid and arid regions is critical for quantification of water resources and contaminant transport. We evaluated system response to paleoclimatic forcing using water potential and Cl profiles and modeling of nonisothermal liquid and vapor flow and Cl transport at semiarid (High Plains, Texas) and arid (Chihuahuan Deser
Authors
Bridget R. Scanlon, K. Keese, R.C. Reedy, Jirka Šimůnek, Brian J. Andraski
Simplified method for detecting tritium contamination in plants and soil
Cost-effective methods are needed to identify the presence and distribution of tritium near radioactive waste disposal and other contaminated sites. The objectives of this study were to (i) develop a simplified sample preparation method for determining tritium contamination in plants and (ii) determine if plant data could be used as an indicator of soil contamination. The method entailed collectio
Authors
Brian J. Andraski, Mark W. Sandstrom, R. L. Michel, J.C. Radyk, David A. Stonestrom, M. J. Johnson, C.J. Mayers
Thermocouple psychrometry
Thermocouple psychrometry is a technique that infers the water potential of the liquid phase of a sample from measurements within the vapor phase that is in equilibrium with the sample. The theoretical relation between water potential of the liquid phase and relative humidity of the vapor phase is given by the Kelvin equation Ψ = energy/volume = (RT/Vw) ln(p/po) [3.2.3–1]where ψ is water potential
Authors
Brian J. Andraski, Bridget R. Scanlon
Selected micrometeorological and soil-moisture data at Amargosa Desert Research Site in Nye County near Beatty, Nevada, 1998-2000
Selected micrometeorological and soil-moisture data were collected at the Amargosa Desert Research Site adjacent to a low-level radioactive waste and hazardous chemical waste facility near Beatty, Nev., 1998-2000. Data were collected in support of ongoing research studies to improve the understanding of hydrologic and contaminant-transport processes in arid environments.
Micrometeorological da
Authors
Michael J. Johnson, Charles J. Mayers, Brian J. Andraski
Miscellaneous methods for measuring matric or water potential
A variety of techniques to measure matric potential or water potential in the laboratory and in the field are described in this section. The techniques described herein require equilibration of some medium whose matric or water potential can be determined from previous calibration or can be measured directly. Under equilibrium conditions the matric or water potential of the medium is equal to that
Authors
Bridget R. Scanlon, Brian J. Andraski, Jim Bilskie
Testing a full‐range soil‐water retention function in modeling water potential and temperature
Recent work has emphasized development of full‐range water‐retention functions that are applicable under both wet and dry soil conditions, but evaluation of such functions in numerical modeling has been limited. Here we show that simulations using the Rossi‐Nimmo (RN) full‐range function compared favorably with those using the common Brooks‐Corey function and that the RN function can improve predi
Authors
Brian J. Andraski, Elizabeth A. Jacobson
Tritium in water vapor in the shallow unsaturated zone at the Amargosa Desert Research Site
Samples of water vapor in soil gas were obtained at the U.S. Geological Survey's Amargosa Desert Research Site in 1997 and 1998 from a depth of 1.5 m (meters) within a 300 m by 300 m grid that lies immediately to the south and west of a low-level radioactive-waste disposal site. The gas samples were analyzed for tritium. Fifty-eight samples were collected in May 1997; 61 samples were collected in
Authors
Richard W. Healy, Robert G. Striegl, Robert L. Michel, David E. Prudic, Brian J. Andraski