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A handbook for the determination of radon attenuation through cover materials

Description: Radon emissions from bare and covered uranium mill tailings can be estimated by diffusion theory if appropriate diffusion coefficients are known. The mathematical basis for the diffusion theory expressions are herein presented, as is a general survey of previous and present research, as well as technological developments associated with randon transport through tailing cover systems. Research is presently being conducted to define more clearly the influences of moisture, porosity, pore size distribution and other factors, on the attenuative properties of cover materials. The results of these present investigations will be incorporated in a subsequent addendum to this handbook. The radon fluxes or cover thicknesses can be calculated by hand or by available computer programs. The equations and procedure for the hand calculations is in direct support of the methodology contained in Appendix P of the Generic Environmental Impact Statement on Uranium Milling. Several examples are given to demonstrate the methodology.
Date: December 1, 1981
Creator: Rogers, V. C. & Nielson, K. K.
Partner: UNT Libraries Government Documents Department

Relationship of observed flow patterns to gas core reactor criticality

Description: The gas core reactor requires the establishment of stable and unique flow patterns. A recent series of room temperature flow tests have studied the hydrodynamics, particularly involving gases of differing densities. In an actual operating gas core reactor, the central gas of vaporized uranium will have a much higher density than the surrounding coolant. Testing was done in two different sized chambers (18 inch and 36 inch diameter) to study hydrodynamic scaling. Air was employed as the ''coolant'' gas. Air, argon, and freon, smoked for identification, was used to simulate the fuel. A variety of injectors at various locations in the cavity were employed. (auth)
Date: January 1, 1975
Creator: Macbeth, P.J.; Kunze, J.F. & Rogers, V.C.
Partner: UNT Libraries Government Documents Department

Characterization of radon penetration of different structural domains of concrete. Final project report

Description: This report documents the research activities by Rogers and Associates Engineering Corporation on grant DE-FG03-93ER61600 during the funded project period from August 1993 to April 1996. The objective of this research was to characterize the mechanisms and rates of radon gas penetration of the different structural domains of the concrete components of residential floor slabs, walls, and associated joints and penetrations. The research was also to characterize the physical properties of the concretes in these domains to relate their radon resistance to their physical properties. These objectives support the broader goal of characterizing which, if any, concrete domains and associated properties constitute robust barriers to radon and which permit radon entry, either inherently or in ways that could be remediated or avoided.
Date: May 1, 1996
Creator: Nielson, K.K. & Rogers, V.C.
Partner: UNT Libraries Government Documents Department

Contaminant pathway analysis and health risk assessment of the Metallurgical Laboratory Basin

Description: The specific objectives of this report are to present a technically detailed site description for the Metallurgical Laboratory basin, to document the manner in which it was modeled by the PATHRAE computer code, and to present the results of the pathway analyses, in terms of both contaminant transport and health risks. This will provide part of a detailed assessment of environmental risks and impacts from the Metallurgical Laboratory both in its present condition and after possible remedial actions to aid in selection of the appropriate remedial action options. In a broader sense, these objectives support the general SRP (Savannah River Plant) operations policy of protecting the environment and the health and safety of the public and operating personnel.
Date: December 1, 1985
Creator: Klein, R. B.; Merrell, G. B.; Nielson, K. K. & Rogers, V. C.
Partner: UNT Libraries Government Documents Department

Lung cancer risks in the vicinity of uranium tailings sites. [UMTRA Project]

Description: Lung cancer mortality data have been assembled for many counties of interest to the Uranium Mill Tailings Remedial Action Program (UMTRAP). The counties generally either contain UMTRAP tailings sites or are adjacent to them. The lung cancer rates of nearly all counties are less than the US average rate. In addition, some of the many factors associated with lung cancer are identified as are cancer risk estimators for radon daughters. 17 refs., 19 figs., 1 tab.
Date: April 1, 1982
Creator: Rogers, V.C. & Sandquist, G.M. (Rogers and Associates Engineering Corp., Salt Lake City, UT (USA))
Partner: UNT Libraries Government Documents Department

Laboratory measurements of radon diffusion through multilayered cover systems for uranium tailings

Description: Laboratory measurements of radon fluxes and radon concentration profiles were conducted to characterize the effectiveness of multilayer cover systems for uranium tailings. The cover systems utilized soil and clay materials from proposed disposal sites for the Vitro, Durango, Shiprock, Grand Junction and Riverton tailings piles. Measured radon fluxes were in reasonable agreement with values predicted by multilayer diffusion theory. Results obtained by using air-filled porosities in the diffusion calculations were similar to those obtained by using total porosities. Measured diffusion coefficients were a better basis for predicting radon fluxes than were correlations of diffusion coefficient with moisture or with air porosity. Radon concentration profiles were also fitted by equations for multilayer diffusion in the air-filled space. Layer-order effects in the multilayer cover systems were examined and estimated to amount to 10 to 20 percent for the systems tested. Quality control measurements in support of the multilayer diffusion tests indicated that moisture absorption was not a significant problem in radon flux sampling with charcoal canisters, but that the geometry of the sampler was critical. The geometric design of flux-can samplers was also shown to be important. Enhanced radon diffusion along the walls of the test columns was examined and was found to be insignificant except when the columns had been physically disturbed. Additional moisture injected into two test columns decreased the radon flux, as expected, but appeared to migrate into surrounding materials or to be lost by evaporation. Control of moisture content and compaction in the test columns appeared to be the critical item affecting the accuracies of the experiments.
Date: December 1, 1981
Creator: Nielson, K.K.; Rogers, V.C.; Rich, D.C.; Nederhand, F.A.; Sandquist, G.M. & Jensen, C.M.
Partner: UNT Libraries Government Documents Department