Hostname: page-component-586b7cd67f-gb8f7 Total loading time: 0 Render date: 2024-11-24T17:57:27.840Z Has data issue: false hasContentIssue false

Preferential Radionuclide Release Due to Alpha Decay: Effects on Repository Performance

Published online by Cambridge University Press:  17 March 2011

David A. Pickett
Affiliation:
Center for Nuclear Waste Regulatory Analyses (CNWRA), Southwest Research Institute®, San Antonio, TX 78228-0210, USA
William M. Murphy
Affiliation:
Department of Geological and Environmental Sciences, California State University, Chico, CA 95929-0205, USA
Get access

Abstract

We model preferential release of 237Np, 234U, 230Th, 226Ra, and 210Pb from disposed commercial spent nuclear fuel as a result of alpha recoil damage, using the U.S. Nuclear Regulatory Commission (NRC) Total-system Performance Assessment (TPA) model for the potential repository at Yucca Mountain. Time-dependent augmentation of the ingrown component is simulated by increasing the initial parent inventory; we have used a factor of five increase, based on natural system observations. For 237Np, the magnitude of preferential release is subject to solubility limits. Stochastic TPA runs show a significant effect on modeled dose of preferential 237Np release, but low impact from the other four radionuclides. The mechanism could be ineffective if 237Np is incorporated into secondary phases. While our results are exploratory in nature, this approach to modeling decay-related enhancement of release can be applied in other nuclear waste disposal settings.

Type
Research Article
Copyright
Copyright © Materials Research Society 2004

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1. CNWRA, Total-System Performance Assessment (TPA) Version 4.0 Code: Module Descriptions and User's Guide (CNWRA, San Antonio, TX, 2000).Google Scholar
2 CRWMS M&O (Civilian Radioactive Waste Management System Management & Operating Contractor), Total System Performance Assessment for Site Recommendation, TDR-WIS-PA-000001 REV 00 ICN 01 (CRWMS M&O, Las Vegas, NV, 2001).Google Scholar
3. Murphy, W.M. and Pickett, D.A. in Radionuclide Retention in Geologic Media. Workshop Proceedings (Nuclear Energy Agency, Paris, 2002), pp. 113118.Google Scholar
4. Murphy, W.M. and Pickett, D.A. in Sci. Basis for Nuclear Waste Mgt. XXV, ed. by McGrail, B. & Cragnolino, G. (Mater. Res. Soc. Proc. 713, Warrendale, PA, 2002), pp. 867874.Google Scholar
5. Poinssot, C., Lovera, P., Faure, M. in Sci. Basis for Nuclear Waste Mgt. XXV, ed. by McGrail, B. & Cragnolino, G. (Mater. Res. Soc. Proc. 713, Warrendale, PA, 2002), pp. 615623.Google Scholar
6. Osmond, J.K. and Cowart, J.B. in Uranium-Series Disequilibrium, 2nd ed., edited by Ivanovich, M. and Harmon, R.S. (Clarendon Press, Oxford, 1992), pp. 290333.Google Scholar
7. Osmond, J.K. and Ivanovich, M. in Uranium-Series Disequilibrium, 2nd ed., edited by Ivanovich, M. and Harmon, R.S. (Clarendon Press, Oxford, 1992), pp. 259289.Google Scholar
8. Porcelli, D. and Swarzenski, P.W. in Uranium-Series Geochemistry, ed. by Bourdon, B., et al. (Rev. Mineral. Geoch. 52, Mineral. Soc. America, Washington, DC, 2003), pp. 317361.Google Scholar
9. CRWMS M&O, Analysis of Geochemical Data for the Unsaturated Zone, ANL-NBS-HS-000017, Rev. 00 (CRWMS M&O, Las Vegas, NV, 2000).Google Scholar
10. Pickett, D.A. and Murphy, W.M. in Sci. Basis for Nuclear Waste Mgt. XXII, edited by Wronkiewicz, D.J. & Lee, J.H. (Mater. Res. Soc. Proc. 556, Warrendale, PA, 1999), pp. 809816.Google Scholar
11. Mohanty, S. et al., System-Level Performance Assessment of the Proposed Repository at Yucca Mountain Using the TPA Version 4.1 Code, 2002-05 (CNWRA, San Antonio, 2002).Google Scholar
12. TRW Environmental Safety Systems Inc., Total System Performance Assessment - 1995, B00000000-01717-2200-00136, Rev. 01 (CRWMS M&O, Las Vegas, NV, 1995).Google Scholar
13. Bechtel SAIC Company, LLC, Dissolved Concentration Limits of Radioactive Elements, ANL-WIS-MD-000010 REV 02 (Bechtel SAIC Company, LLC, Las Vegas, NV, 2003).Google Scholar
14. Murphy, W.M. and Codell, R.C. in Sci. Basis for Nuclear Waste Mgt. XXII, edited by Wronkiewicz, D.J. & Lee, J.H. (Mater. Res. Soc. Proc. 556, Warrendale, PA, 1999), pp. 551558.Google Scholar