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Review of Gaussian diffusion-deposition models

Description: The assumptions and predictions of several Gaussian diffusion-deposition models are compared. A simple correction to the Chamberlain source depletion model is shown to predict ground-level airborne concentrations and dry deposition fluxes in close agreement with the exact solution of Horst.
Date: January 1, 1979
Creator: Horst, T.W.
Partner: UNT Libraries Government Documents Department
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Lagrangian similarity modeling of vertical diffusion from a ground-level source

Description: Several alternate Lagrangian similarity predictions of turbulent diffusion in a thermally-stratified turbulent shear flow were compared with the Prairie Grass ground-level, crosswind-integrated tracer concentration data. The best agreement with the data was found by assuming that the eddy diffusivity K of a passive contaminant corresponds to that of heat, by using an exponent r equal to 1.5 or 2 in the vertical contaminant distribution exp(-(anti z/b anti z)/sup r/), and by using Chaudhry and M… more
Date: January 1, 1979
Creator: Horst, T. W.
Partner: UNT Libraries Government Documents Department
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Estimation of air concentrations due to the suspension of surface contamination by the wind

Description: A mathematical model is developed for the calculation of air concentrations of material suspended by the wind from areas of surface contamination and the model is applied specifically to the BC Controlled Area. Example computer solutions are given to show the dependence of the suspended air concentration on suspension rate, deposition velocity, wind speed, wind direction and atmospheric stability. This model is subsequently simplified to produce an analytical method for the economical estimatio… more
Date: March 1, 1976
Creator: Horst, T. W.
Partner: UNT Libraries Government Documents Department
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Resuspension of material dispersed by atmospheric diffusion from a point source

Description: One year of hourly data from the Hanford Meteorological Tower has been selected to represent a typical climatological distribution of the meteorological variables which control atmospheric diffusion, deposition, and resuspension. This data was used in a surface flux model to predict the probable value of both the initial air concentration, accounting for the depletion due to deposition, and the consequent air concentration of resuspended material whose source is the material deposited on the gr… more
Date: December 1, 1975
Creator: Horst, T.W.
Partner: UNT Libraries Government Documents Department
open access

Simple nocturnal slope-flow data from the Rattlesnake Mountain site

Description: Detailed vertical profiles of the wind and temperture structure of nocturnal slope flows were measured at a site that is uniform in the cross-slope direction. The upper part of the slope closely approximates a simple, tilted plane. These measurements were made from three towers at different distances from the ridge crest, each of which extended through the local depth of the katabatic flow. The tower wind and temperature data from the four best cases of slope flow observed in 1980 and 1981 are … more
Date: October 1, 1982
Creator: Horst, T.W. & Doran, J.C.
Partner: UNT Libraries Government Documents Department
open access

Field and modeling study of windblown particles from a uranium mill tailings pile. Interim report

Description: A field study is reported, showing that for a carbonate-leach-process mill tailings pile in the Grants, New Mexico region much of the residual radioactive constituents in the tailings is found associated with particles 7 ..mu..m in diameter and smaller. As the tailings material dries, particle attachment and aggregation occurs with the result that radioactive constituents become associated more with larger particles. Soil samples taken at surface and subsurface on radial lines extending from th… more
Date: April 1, 1979
Creator: Schwendiman, L. C.; Sehmel, G. A.; Horst, T. W.; Thomas, C. W. & Perkins, R. W.
Partner: UNT Libraries Government Documents Department
open access

Annual report, October 1980-September 1981 Multimedia radionuclide exposure assessment modeling.

Description: Pacific Northwest Laboratory (PNL) and Los Alamos National Laboratory (LANL) are jointly developing a methodology for assessing exposures of the air, water, and plants to radionuclides as part of an overall development effort of a radionuclide disposal site evaluation methodology. Work in FY-1981 continued the development of the Multimedia Contaminant Environmental Exposure Assessment (MCEA) methodology and initiated an assessment of radionuclide migration in Los Alamos and Pueblo Canyons, New … more
Date: December 1, 1982
Creator: Whelan, G.; Onishi, Y.; Simmons, C.S.; Horst, T.W.; Gupta, S.K.; Orgill, M.M. et al.
Partner: UNT Libraries Government Documents Department
open access

A Field and Modeling Study of Windblown Particles from a Uranium Mill Tailings Pile

Description: An extensive field study whose primary objective was to obtain knowledge and understanding of the nature and quantity of windblown particles from uranium mill tailings piles was conducted in the Ambrosia Lake District of New Mexico. The following major field tasks were undertaken: determination of physical, chemical, and radioactivity characteristics of mill tailings particles; an investigation of the nature and quantity of tailings particles in soil in the vicinity of tailings piles; and the d… more
Date: June 1, 1980
Creator: Schwendiman, L. C.; Sehmel, G. A.; Horst, T. W.; Thomas, C. W. & Perkins, R. W.
Partner: UNT Libraries Government Documents Department
open access

Evaluation of empirical atmospheric diffusion data

Description: A study has been made of atmospheric diffusion over level, homogeneous terrain of contaminants released from non-buoyant point sources up to 100 m in height. Current theories of diffusion are compared to empirical diffusion data, and specific dispersion estimation techniques are recommended which can be implemented with the on-site meteorological instrumentation required by the Nuclear Regulatory Commission. A comparison of both the recommended diffusion model and the NRC diffusion model with t… more
Date: October 1, 1979
Creator: Horst, T. W.; Doran, J. C. & Nickola, P. W.
Partner: UNT Libraries Government Documents Department
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