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in creator/contributor: "Cawlfield, D.E."  
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Numerical modeling studies on the alternately pulsed infiltration and subsequent evaporation of water in a dry high desert alluvial soil

Description: The concept of no liquid-phase migration of low-level radionuclides is extremely important for the U.S. Department of Energy, Nevada Operations Office (USDOE/NV) Low-Level Radioactive Waste Management Sites (RWMS) in Areas 3 and 5 of the Nevada Test Site (NTS). Each site location is situated in an area known for its dry conditions. A series of computer modeling problems were set up to study the effects of pulsing the desert surface with large amounts of water, followed by intense evaporative co… more
Date: December 31, 1993
Creator: Cawlfield, D. E.; Lindstrom, F. T. & Weaver, H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Sensitivity analysis of the noble gas transport and fate model: CASCADR9

Description: CASCADR9 is a desert alluvial soil site-specific noble gas transport and fate model. Input parameters for CASCADR9 are: man-made source term, background concentration of radionuclides, radon half-life, soil porosity, period of barometric pressure wave, amplitude of barometric pressure wave, and effective eddy diffusivity. Using average flux, total flow, and radon concentration at the 40 day mark as output parameters, a sensitivity analysis for CASCADR9 is carried out, under a variety of scenari… more
Date: March 1, 1994
Creator: Lindstrom, F. T.; Cawlfield, D. E. & Barker, L. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A water infiltration model: Study of reusability in an environmental engineering problem

Description: The paper describes a computer simulation, involving a site characterization for the storage of low-level radioactive waste at the Nevada Test Site, in order to highlight the reutilization in that project of skills and tools used in aerospace computing.
Date: March 1, 1995
Creator: Cawlfield, D.E.; Lindstrom, F.T. & Miel, G.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A modeling study of the effect of depth of burial of depleted uranium and thorium on radon gas flux at a dry desert alluvial soil radioactive waste management site (RWMS)

Description: An integral part of designing low-level waste (LLW) disposal pits and their associated closure covers in very dry desert alluvium is the use of a radon gas transport and fate model. Radon-222 has the potential to be a real heath hazard. The production of radon-222 results from the radioactive decay (a particle emission) of radium-226 in the uranium-235 and 238 Bateman chains. It is also produced in the thorium-230 series. Both long lived radionuclides have been proposed for disposal in the shal… more
Date: August 1, 1993
Creator: Lindstrom, F. T.; Cawlfield, D. E.; Emer, D. F. & Shott, G. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

CASCADER: An M-chain gas-phase radionuclide transport and fate model. Volume 4 -- Users guide to CASCADR9

Description: Chemicals and radionuclides move either in the gas-phase, liquid-phase, or both phases in soils. They may be acted upon by either biological or abiotic processes through advection and/or dispersion. Additionally during the transport of parent and daughter radionuclides in soil, radionuclide decay may occur. This version of CASCADER called CASCADR9 starts with the concepts presented in volumes one and three of this series. For a proper understanding of how the model works, the reader should read… more
Date: September 1, 1993
Creator: Cawlfield, D. E.; Emer, D. F.; Lindstrom, F. T. & Shott, G. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A simulation of the transport and fate of radon-222 derived from thorium-230 low-level waste in the near-surface zone of the Radioactive Waste Management Site in Area 5 of the Nevada Test Site

Description: US Department of Energy (DOE) Order 5820.2A (DOE, 1988) requires performance assessments on all new and existing low-level radioactive waste (LLW) disposal sites. An integral part of performance assessment is estimating the fluxes of radioactive gases such as radon-220 and radon-222. Data needs pointed out by mathematical models drive site characterization. They provide a logical means of performing the required flux estimations. Thorium-230 waste, consisting largely of thorium hydroxide and th… more
Date: December 1, 1993
Creator: Lindstrom, F. T.; Cawlfield, D. E.; Donahue, M. E.; Emer, D. F. & Shott, G. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

CASCADER: An m-chain gas-phase radionuclide transport and fate model. Volume 2, User`s manual for CASCADR8

Description: Chemicals and radionuclides move either in the gas-phase, liquid-phase, or both phases in soils. They may be acted upon by either biological or abiotic processes through advection and/or diffusion. Furthermore, parent and daughter radionuclides may decay as they are transported in the soil. This is volume two to the CASCADER series, titled CASCADR8. It embodies the concepts presented in volume one of this series. To properly understand how the CASCADR8 model works, the reader should read volume… more
Date: June 1, 1993
Creator: Cawlfield, D. E.; Been, K. B.; Emer, D. F.; Lindstrom, F. T. & Shott, G. J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Estimating the water table under the Radioactive Waste Management Site in Area 5 of the Nevada Test Site: The Dupuit-Forcheimer approximation

Description: To adequately manage the low level nuclear waste (LLW) repository in Area 5 of the Nevada Test Site (NTS), a knowledge of the water table under the site is paramount. The estimated thickness of the arid intermountain basin alluvium is roughly 900 feet. Very little reliable water table data for Area 5 currently exists. The Special Projects Section of the Reynolds Electrical & Engineering Co., Inc. Waste Management Department is currently formulating a long-range drilling and sampling plan in sup… more
Date: June 1, 1992
Creator: Lindstrom, F. T.; Barker, L. E.; Cawlfield, D. E.; Daffern, D. D.; Dozier, B. L.; Emer, D. F. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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