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Relationships of dispersive mass transport and stochastic convective flow through hydrologic systems

Description: Uncertainty in water flow velocity appears to be a major factor in determining the magnitude of contaminant dispersion expected in a ground water system. This report discusses some concepts and mathematical methods relating dispersive contaminant transport to stochastic aspects of ground water flow. The theory developed should not be construed as absolutely rigorous mathematics, but is presented with the intention of clarifying the physical concepts.
Date: January 1, 1981
Creator: Simmons, C.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Volume 2. Special test cases

Description: This document was written for the National Low-Level Waste Management Program to provide guidance for managers and site operators who need to select ground-water transport codes for assessing shallow-land burial site performance. The guidance given in this report also serves the needs of applications-oriented users who work under the direction of a manager or site operator. The guidelines are published in two volumes designed to support the needs of users having different technical backgrounds.… more
Date: August 1, 1985
Creator: Simmons, C.S. & Cole, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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INFIL1D: a quasi-analytical model for simulating one-dimensional, constant flux infiltration

Description: The program INFIL1D is designed to calculate approximate wetting-front advance into an unsaturated, uniformly moist, homogeneous soil profile, under constant surface-flux conditions. The code is based on a quasi-analytical method, which utilizes an assumed invariant functional relationship between reduced (normalized) flux and water content. The code uses general hydraulic property data in tabular form to simulate constant surface-flux infiltration. 10 references, 4 figures.
Date: April 1, 1984
Creator: Simmons, C.S. & McKeon, T.J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Simulation of water flow and retention in earthen-cover materials overlying uranium mill tailings

Description: The water retention characteristics of a multilayer earthen cover for uranium mill tailings were simulated under arid weather conditions common to Grand Junction, Colorado. The multilayer system described in this report consists of a layer of wet clay/gravel (radon barrier), which is separated from a surface covering of fill soil by a washed rock material used as a capillary barrier. The capillary barrier is designed to prevent the upward migration of water and salt from the tailings to the soi… more
Date: September 1, 1981
Creator: Simmons, C.S. & Gee, G.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Executive summary

Description: This document was written to provide guidance to managers and site operators on how ground-water transport codes should be selected for assessing burial site performance. There is a need for a formal approach to selecting appropriate codes from the multitude of potentially useful ground-water transport codes that are currently available. Code selection is a problem that requires more than merely considering mathematical equation-solving methods. These guidelines are very general and flexible an… more
Date: May 1, 1985
Creator: Simmons, C.S. & Cole, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Guidelines for selecting codes for ground-water transport modeling of low-level waste burial sites. Volume 1. Guideline approach

Description: This document was written for the National Low-Level Waste Management Program to provide guidance for managers and site operators who need to select ground-water transport codes for assessing shallow-land burial site performance. The guidance given in this report also serves the needs of applications-oriented users who work under the direction of a manager or site operator. The guidelines are published in two volumes designed to support the needs of users having different technical backgrounds.… more
Date: May 1, 1985
Creator: Simmons, C.S. & Cole, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Characterization of the Hanford 300 Area Burial Grounds. Task III: fluid transport and modeling

Description: In Task III, Fluid Transport and Modeling, a computer model was developed and applied to the 300 Area Burial Grounds to analyze the influence of potential evaporation and rainfall patterns on drainage. The model describes one-dimensional unsaturated flow. Fluid transport equations were evaluated to describe the driving forces of fluid flow. The data indicate that the major processes are evaporative drying, capillarity, and gravity flow. Thermally induced transport does not appear significant in… more
Date: August 1, 1979
Creator: Gee, G.W. & Simmons, C.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Subsurface flow and transport of organic chemicals: an assessment of current modeling capability and priority directions for future research (1987-1995)

Description: Theoretical and computer modeling capability for assessing the subsurface movement and fate of organic contaminants in groundwater was examined. Hence, this study is particularly concerned with energy-related, organic compounds that could enter a subsurface environment and move as components of a liquid phase separate from groundwater. The migration of organic chemicals that exist in an aqueous dissolved state is certainly a part of this more general scenario. However, modeling of the transport… more
Date: September 1, 1986
Creator: Streile, G.P. & Simmons, C.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Modeling water retention of sludge simulants and actual saltcake tank wastes

Description: The Ferrocyanide Tanks Safety Program managed by Westinghouse hanford Company has been concerned with the potential combustion hazard of dry tank wastes containing ferrocyanide chemical in combination with nitrate salts. Pervious studies have shown that tank waste containing greater than 20 percent of weight as water could not be accidentally ignited. Moreover, a sustained combustion could not be propagated in such a wet waste even if it contained enough ferrocyanide to burn. Because moisture c… more
Date: July 1, 1996
Creator: Simmons, C.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A simplified model of saltcake moisture distribution. Letter report

Description: This letter report describes the formulation of a simplified model for finding the moisture distribution in a saltcake waste profile that has been stabilized by pumping out the drainable interstitial liquid. The model is based on assuming that capillarity mainly governs the distribution of moisture in the porous saltcake waste. A stead upward flow of moisture driven by evaporation from the waste surface is conceptualized to occur for isothermal conditions. To obtain hydraulic parameters for uns… more
Date: September 1, 1995
Creator: Simmons, C.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multicomponent mass transport model: a model for simulating migration of radionuclides in ground water

Description: This report presents the results of the development of a one-dimensional radionuclide transport code, MMT2D (Multicomponent Mass Transport), for the AEGIS Program. Multicomponent Mass Transport is a numerical solution technique that uses the discrete-parcel-random-wald (DPRW) method to directly simulate the migration of radionuclides. MMT1D accounts for: convection;dispersion; sorption-desorption; first-order radioactive decay; and n-membered radioactive decay chains. Comparisons between MMT1D … more
Date: July 1, 1980
Creator: Washburn, J.F.; Kaszeta, F.E.; Simmons, C.S. & Cole, C.R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Dryout modeling in support of the organic tank safety project

Description: This work was performed for the Organic Tank Safety Project to evaluate the moisture condition of the waste surface organic-nitrate bearing tanks that are classified as being conditionally safe because sufficient water is present. This report describes the predictive modeling procedure used to predict the moisture content of waste in the future, after it has been subjected to dryout caused by water vapor loss through passive ventilation. This report describes a simplified procedure for modeling… more
Date: August 1, 1998
Creator: Simmons, C.S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Chief Joseph Kokanee Enhancement Project : Strobe Light Deterrent Efficacy Test and Fish Behavior Determination at Grond Coulee Dam Third Powerplant Forebay.

Description: Since 1995, the Colville Confederated Tribes have managed the Chief Joseph Kokanee Enhancement Project as part of the Northwest Power Planning Council's (NWPPC) Fish and Wildlife Program. Project objectives have focused on understanding natural production of kokanee (a land-locked sockeye salmon) and other fish stocks in the area above Grand Coulee and Chief Joseph Dams on the Columbia River. A 42-month investigation concluded that entrainment at Grand Coulee Dam ranged from 211,685 to 576,676 … more
Date: January 1, 2002
Creator: Simmons, M. A.; McKinstry, C. A. & Simmons, C. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characterization of the Hanford 300 area burial grounds. Final report: decontamination and decommissioning

Description: Pacific Northwest Laboratory conducted a series of investigations at the Hanford Site to develop technologies for characterizing and monitoring radioactive waste burial facilities that could be used in determining appropriate decommissioning alternatives. Specific objectives were to develop unique functional geophysics, geochemical, soil physics, numerical modeling, and biological methodologies needed to better characterize and monitor buried radioactive waste disposal sites. To meet these obje… more
Date: January 1, 1980
Creator: Phillips, S. J.; Ames, L. L.; Fitzner, R. E.; Gee, G. W.; Sandness, G. A. & Simmons, C. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Developing a model for moisture in saltcake waste tanks: Progress report

Description: This report describes a modeling effort to provide a computer simulation capability for estimating the distribution and movement of moisture in the saltcake-type waste contained in Hanford`s single-shell radioactive waste storage tanks. This moisture model goes beyond an earlier version because it describes water vapor movement as well as the interstitial liquid held in a saltcake waste. The work was performed by Pacific Northwest National Laboratory to assist Duke Engineering and Services Hanf… more
Date: July 1, 1997
Creator: Simmons, C. S.; Aimo, N.; Fayer, M. J. & White, M. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Ferrocyanide safety program: An assessment of the possibility of ferrocyanide sludge dryout

Description: Much attention has been focused on the Hanford Site radioactive waste storage tanks as a results of problems that have been envisioned for them. One problem is the potential chemical reaction between ferrocyanide precipitate particles and nitrates in the absence of water. This report addresses the question of whether dryout of a portion of ferrocyanide sludge would render it potentially reactive. Various sludge dryout mechanisms were examined to determine if any of them could occur. The mechani… more
Date: September 1, 1994
Creator: Epstein, M.; Fauske, H. K.; Dickinson, D. R.; Crippen, M. D.; McCormack, J. D.; Cash, R. J. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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