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Determination of Technetium and Selenium Transport Properties in Laboratory Soil Columns

Published online by Cambridge University Press:  26 February 2011

J. A. Del Debbio
Affiliation:
Westinghouse Idaho Nuclear Co., P.O. Box 4000, Idaho Falls, Idaho 83403, USA
T. R. Thomas
Affiliation:
Westinghouse Idaho Nuclear Co., P.O. Box 4000, Idaho Falls, Idaho 83403, USA
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Abstract

Laboratory studies are being conducted to measure the transport properties of various radionuclide species through soil columns. The studies are being conducted to support evaluations for potential near-surface disposal of high-level radioactive waste (HLW) calcine stored at the Idaho National Engineering Laboratory. The data will be used to model radionuclide transport through the vadose (unsaturated) zone of the site under various water-contact scenarios. Retardation factors and dispersion coefficients for technetium and selenium species have been measured in water-saturated soil columns made up of sediments taken from 12 and 35 meters below the surface. A one-dimensional, convective-dispersive, solute-transport equation was fitted to column effluent data by optimizing three parameters (retardation factor, dispersion coefficient and pulse time) using a non-linear, least-squares fitting routine. The data indicated no retardation of the pertechnetate ion (TcO4-)and selenate ion (SeO4-) and a large retardation of the selenite ion (SeO3-) relative to water transport through the soil column.

Type
Research Article
Copyright
Copyright © Materials Research Society 1989

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References

REFERENCES

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