Application of Bootstrap in Dose Apportionment of Nuclear Plants Via Uncertainty Modeling of the Effluent Released from Plants
- 1
Abstract
Nuclear power plants are always operated under the guidelines stipulated by the regulatory body. These guidelines basically contain the technical specifications of the specific power plant and provide the knowledge of the discharge limit of the radioactive effluent into the environment through atmospheric and aquatic route. However, operational constraints sometimes may violate the technical specification due to which there may be a failure to satisfy the stipulated dose apportioned to that plant. In a site having multi facilities sum total of the dose apportioned to all the facilities should be constrained to 1 mSv/year to the members of the public. Dose apportionment scheme basically stipulates the limit of the gaseous and liquid effluent released into the environment. Existing methodology of dose apportionment is subjective in nature that may result the discharge limit of the effluent in atmospheric and aquatic route in an adhoc manner. Appropriate scientific basis for dose apportionment is always preferable rather than judicial basis from the point of harmonization of establishing the dose apportionment. This paper presents an attempt of establishing the discharge limit of the gaseous and liquid effluent first on the basis of the existing value of the release of the same. Existing release data for a few years (for example 10 years) for any nuclear power station have taken into consideration. Bootstrap, a resampling technique, has been adopted on the existing release data sets to generate the corresponding population distribution of the effluent release. Cumulative distribution of the population distribution obtained is constructed and using this cumulative distribution, 95th percentile (upper bound) of the discharge limit of the radioactive effluents is computed. Dose apportioned for a facility is evaluated using this estimated upper bound of the release limit. Paper de- scribes the detail of the bootstrap method in evaluating the release limit and also presents the comparative study of the dose apportionment using this new method and the existing adhoc method.
- B. Efron and R. J. Tibshirani, “An Introduction to the Bootstrap,” Chapman and Hall, New York, 1993.
- “International Commission on Radiological Protection, 1990 Recommendations of the International Commission on Radiological Protection,” ICRP Publication 60, Per- gamon Press, Oxford and New York, 1991.
- M. Balonov, G. Linsley, D. Louvat, C. Robinson and T. Cabianca, “The IAEA Standards for the Radioactive Dis- charge Control: Present Status and Future Development,” Radioprotection, Vol. 40, Suppl. 1, S721-S726, 2005. doi:10.1051/radiopro:2005s1-105
- International Atomic Energy Agency, “Regulatory Con- trol of Radioactive Discharges to the Environment,” Sa- fety Standards Series No. WS-G-2.3, IAEA, Vienna, 2000.
- M. R. Chernick, “Bootstrap Methods, A Practitioner’s Guide,” Wiley, New York, 1999.
- P. Hall, “The Bootstrap and Edgeworth Expansion,” Sprin- ger-Verlag, New York, 1992.
- G. Archer and J. M. Giovannoni, “Statistical Analysis with Bootstrap Diagnostics of Atmospheric Pollutants Pre- dicted in the APSIS Experiment,” Water, Air, and Soil Pollution, Vol. 106, No. 1-2, 1998, pp. 43-81. doi:10.1023/A:1005004022883
- A. C. Davison and D. V. Hinkley, “Bootstrap Methods and Their Application,” Cambridge University Press, Cambri- dge, 1997.
- B. Efron, “The Jackknife, the Bootstrap and Other Resam- pling Plans,” SIAM, Philadelphia, 1982. doi:10.1137/1.9781611970319
- E. J. Dudewicz, “The Generalized Bootstrap,” In: K.-H. J?ckel, G. Rothe and W. Sendler, Eds., Bootstrapping and Related Techniques, Springer-Verlag, Berlin, 1992, pp. 31-37.
- T. J. DiCiccio and B. Efron, “Bootstrap Confidence Inter- vals (with Discussion),” Statistical Science, Vol. 11, No. 3, 1996, pp. 189-228.
- International Atomic Energy Agency, “Generic Models for Use in Assessing the Impact of Discharges of Radio- active Substances to the Environment,” Safety Reports Series No. 19, IAEA, Vienna, 2001.
- International Atomic Energy Agency, “Basic Safety Stan- dards Series,” SS No. 115, IAEA, Vienna, 1996.
- A. J. Bailer and J. T. Oris, “Assessing Toxicity of Pollut- ants in Aquatic Systems,” In: N. Lange, L. Ryan, L. Billard, D. Brillinger, L. Conquest and J. Greenhouse, Eds., Case Studies in Biometry, Wiley, New York, pp. 25-40, 1994.
- R. L. Cooley, “Confidence Intervals for Groundwater Mo- dels Using Linearization, Likelihood, and Bootstrap me- thods,” Ground Water, Vol. 35, No. 5, 1997, pp. 869-880. doi:10.1111/j.1745-6584.1997.tb00155.x