HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Nielson, K. K. Articles by Gee, G. W. Search for Related Content PubMed Articles by Nielson, K. K. Articles by Gee, G. W. Agricola Articles by Nielson, K. K. Articles by Gee, G. W.

Diffusion of Radon through Soils: A Pore Distribution Model¹

ABSTRACT

A mathematical model was developed for calculating radon diffusion coefficients from water contents and pore size distributions of soil materials. The model accounts for radon diffusion in the air-filled and the water-filled pore space, for radon solubility in water, and for Knudsen diffusion in extremely small air-filled spaces. The model considers soil pores to be composed of all possible serial combinations of the size increments from a measured pore size distribution. Diffusion coefficients for the resulting composite pores are computed and then used to calculate the overall diffusion coefficient of the soil by assuming parallel diffusion through all of the pore combinations. The resulting diffusion coefficients increase with the median pore diameter, and decrease with increasing soil water contents and with increasing widths of the soil pore size distribution. The model diffusion coefficients compare well with measured coefficients and with empirical calculations and are useful in evaluating the required soil cover thickness for uranium mill tailings reclamation.

¹ Contribution from Rogers and Associates Engineering Corp., Salt Lake City, UT and Pacific Northwest Lab., Richland, WA. Work was supported by the U.S. Nuclear Regulatory Commission and by the U.S. Department of Energy (Uranium Mill Tailings Remedial Action Project) under Contract DE-AC06-76RLO-1830.

² Senior Scientist and President, Rogers and Associates Engineering Corp., and Staff Scientist, Pacific Northwest Lab.

Received for publication March 21, 1983. Accepted for publication October 20, 1983.

This article has been cited by other articles:

				V. L. Freedman, D. H. Bacon, K. P. Saripalli, and P. D. Meyer A Film Depositional Model of Permeability for Mineral Reactions in Unsaturated Media Vadose Zone J., November 1, 2004; 3(4): 1414 - 1424. [Abstract] [Full Text] [PDF]

				P. Moldrup, T. Olesen, S. Yoshikawa, T. Komatsu, and D. E. Rolston Three-Porosity Model for Predicting the Gas Diffusion Coefficient in Undisturbed Soil Soil Sci. Soc. Am. J., May 1, 2004; 68(3): 750 - 759. [Abstract] [Full Text] [PDF]

				P. Moldrup, T. Olesen, P. Schjønning, T. Yamaguchi, and D.E. Rolston Predicting the Gas Diffusion Coefficient in Undisturbed Soil from Soil Water Characteristics Soil Sci. Soc. Am. J., January 1, 2000; 64(1): 94 - 100. [Abstract] [Full Text]