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Title: ISO standardization of scaling factor method for low and intermediate level radioactive wastes generated at nuclear power plants

Conference ·
OSTI ID:21156266
 [1]; ;  [2];  [3];  [4];  [5];  [6];  [7];  [8];  [9]
  1. JGC Corporation (Japan)
  2. Tokyo Electric Power Company, Incorporated -TEPCO (Japan)
  3. DW James Consulting (United States)
  4. Electricite de France - EDF (France)
  5. ISTec, Forschungsgelaende, Garching b., Muenchen D-85748 (Germany)
  6. Ontario Power Generation - OPG (Canada)
  7. Empresa Nacional de Residuos Radioactivos S.A. - ENRESA (Spain)
  8. National Co-operative for the Disposal of Radioactive Waste - NAGRA (Switzerland)
  9. Nuclear Research and Consulting Group - NRG (Netherlands)

Low- and intermediate-level radioactive wastes (L-ILW ) generated at nuclear power plants are disposed of in various countries. In the disposal of such wastes, it is required that the radioactivity concentrations of waste packages should be declared with respect to difficult-to-measure nuclides (DTM nuclides), such as C-14, Ni-63 and a-emitting nuclides, which are often limited to maximum values in disposal licenses, safety cases and/or regulations for maximum radioactive concentrations. To fulfill this requirement, the Scaling Factor method (SF method) has been applied in various countries as a principal method for determining the concentrations of DTM nuclides. In the SF method, the concentrations of DTM nuclides are determined by multiplying the concentrations of certain key nuclides by SF values (the determined ratios of radioactive concentration between DTM nuclides and those key nuclides). The SF values used as conversion factors are determined from the correlation between DTM nuclides and key nuclides such as Co-60. The concentrations of key nuclides are determined by {gamma} ray measurements which can be made comparatively easily from outside the waste package. The SF values are calculated based on the data obtained from the radiochemical analysis of waste samples. The use of SFs, which are empirically based on analytical data, has become established as a widely recognized 'de facto standard'. A number of countries have independently collected nuclide data by analysis over many years and each has developed its own SF method, but all the SF methods that have been adopted are similar. The project team for standardization had been organized for establishing this SF method as a 'de jure standard' in the international standardization system of the International Organization for Standardization (ISO). The project team for standardization has advanced the standardization through technical studies, based upon each country's study results and analysis data. The conclusions reached by the project team was published as ISO International Standard 21238:2007 'The Scaling Factor method to determine the radioactivity of low- and intermediate-level radioactive waste packages generated at nuclear power plants'. This paper gives an introduction to the international standardization process for the SF method and the contents of the recently published International Standard. (authors)

Research Organization:
American Society of Mechanical Engineers (ASME), Three Park Avenue, New York, NY 10016-5990 (United States); Technological Institute of the Royal Flemish Society of Engineers (TI-K VIV), Het Ingenieurshuis, Desguinlei 214, 2018 Antwerp (Belgium); Belgian Nuclear Society (BNS) - ASBL-VZW, c/o SCK-CEN, Avenue Hermann Debrouxlaan, 40 - B-1160 Brussels (Belgium)
OSTI ID:
21156266
Resource Relation:
Conference: ICEM'07: 11. International Conference on Environmental Remediation and Radioactive Waste Management, Bruges (Belgium), 2-6 Sep 2007; Other Information: Country of input: France; 1 ref.; Proceedings may be ordered from ASME Order Department, 22 Law Drive, P.O. Box 2300, Fairfield, NJ 07007-2300 (United States)
Country of Publication:
United States
Language:
English