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Transport of 14C and Uranium in the Carrizo Aquifer of South Texas, a Natural Analog of Radionuclide Migration

Published online by Cambridge University Press:  25 February 2011

Robert W. Andrews  and
F. J. Pearson Jr.
Robert W. Andrews
Affiliation:
INTERA Environmental Consultants, Inc.,11999 Katy Freeway,Suite 610,Houston,Texas 77079
F. J. Pearson Jr.
Affiliation:
INTERA Environmental Consultants, Inc.,11999 Katy Freeway,Suite 610,Houston,Texas 77079
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Abstract

Ground-water flow and transport were modeled along a one-dimensional, vertical cross-section of the Carrizo aquifer from its outcrop down gradient for 100 km. Using a constant flux of 14C at the recharge boundary, the 14C mass fraction distribution downgradient was simulated until steady-state was attained. The match between the observed data and simulated results is excellent for a porosity of 35% and a KD of zero. The transport of both 234U and 238U was simulated with varying retardation coefficients. The best fit occurred with a RD of about 30, which corresponds to a KD of 6. The results indicate that modeling may be reliably conducted over time periods and distances of interest in radionuclide transport performance assessments and that regionally averaged hydrologic properties can provide appropriate values for predicting ground-water flow and nuclide transport.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 26: Symposium D – Scientific Basis for Nuclear Waste Management VII , 1983 , 1085
Copyright
Copyright © Materials Research Society 1984

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References

REFERENCES

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