Refresher course 2A

Topic:
Assessing public exposure from NORM discharges – key parameters and simple approaches to dose estimates.

Lecturer(s):
Christian Kunze (IAF-Radioökologie, Dresden-Radeberg, Germany) (Organised in co-operation with ENA)

Learning objectives of the refresher course:
The objective of the refresher course is to provide an overview of methods to assess the source term of radioactive discharges from NORM industries, and to estimate the resulting doses for members of the public. Participants will learn the following:

  • How to estimate the discharges from NORM industry – source terms and typical nuclide vectors,
  • How to identify key input parameters to dose estimates for the general public,
  • How to take atmospheric and waterborne transport of radionuclides into account,
  • How to assess the radiological relevance of discharges from NORM industries with respect to exposure of the general public.

Summary:
In transposing Directive 2013/59/Euratom (European Basic Safety Standards or EU BSS) into national law, member states are required to identify industrial sectors which involve naturally occurring radioactive materials (NORM), which may lead to public exposure that cannot be disregarded from a radiation protection point of view. This involves a comprehensive survey of all potentially relevant industrial sectors, and determination of source terms of water- and airborne discharges, atmospheric and hydrographic dispersion, in order to carry out dose estimates and assess the radiological relevance of industries involving NORM.

Using the example of Germany, the course will explain how discharge and deposition of dust in agricultural and horticultural areas, being the most relevant dispersion and exposure pathways, is turned into dose estimates for members of the public. In addition, waterborne discharges are considered, and order-of-magnitude estimates are presented to estimate doses via the water path.

While rather comprehensive models are usually thought to be necessary, their complexity may distract users from the fact that very few key parameters and assumptions determine the effective dose of members of the public. This refresher course will therefore identify parameters and assumptions that have turned out to be central in all subsequent considerations, and provide a simplified, generic, yet sufficiently reliable and robust assessment methodology to determine the radiological relevance of dust and waterborne discharges from NORM industries. Due to its simplicity and robustness, the methodology can also be adapted to conditions in other countries in a straightforward way.

List of recommended (pre)reading literature:

  1. Kunze, H. Schulz, E. Ettenhuber, A. Schellenberger, J. Dilling: Discharges of dust from NORM facilities: Key parameters to assess effective doses for public exposure, Journal of Sustainable Mining 18 (2019) pp. 31–37, available from https://www.sciencedirect.com/journal/journal-of-sustainable-mining/special-issue/104DZT3RTPZ
  2. Schulz, C. Kunze, H. Hummrich: Balance of natural radionuclides in lignite-based power generation and consequences for the use of residues and by-products. 8th EAN_NORM Workshop, Stockholm, 5-7 December 2016, available from https://ena-norm.eu/wp-content/uploads/2018/03/8_1_12_Schulz_Balance-of-natural-radionuclides.pdf
  3. Kunze, E. Ettenhuber, A. Schellenberger, H. Schulz: Identification and radiological assessment of relevant discharges and releases from German industries, Final Report, Federal Office for Radiation Protection, Contract No. 3615S12232, Salzgitter, October 2018, available from https://doris.bfs.de/jspui/handle/urn:nbn:de:0221-2018101516404
  4. European Commission: RP 135 – Effluent and dose control from European Union NORM industries: Assessment of current situation and proposal for a harmonised Community approach. European Commission, Directorate-General for Energy and Transport, Directorate H – Nuclear Safety and Safeguards, Unit H.4 – Radiation Protection, 2003
  5. INTERNATIONAL ATOMIC ENERGY AGENCY, Extent of Environmental Contamination by Naturally Occurring Radioactive Materials (NORM) and Technological Options for Mitigation, Technical Report Series No. 419, Vienna (2003)
  6. INTERNATIONAL ATOMIC ENERGY AGENCY, Exposure of the Public from Large Deposits of Mineral Residues, TECDOC No. 1660, Vienna (2011)
  7. UNSCEAR, Sources and Effects of Ionising Radiation, 1988 Report to the General Assembly, with Scientific Annexes. United Nations Scientific Committee on the Effects of Atomic Radiation, New York, 1988
  8. P. Leenhouts, P. Stoop, S.T. van Tuinen: Non-nuclear Industries in the Netherlands and Radiological Risks, RIVM Report 610053003, 1996
  9. P. Ryan, A. Janssens, E. Henrich, J.-L. Daroussin, Z.K. Hillis, E.I.M. Meijne: Industries giving rise to NORM discharges in the European Union – A review, Proceedings of an international conference (NORM IV) held in Szczyrk, Poland, 17-21 May 2004
  10. Crockett, G.M., Smith, K.R., Oatway, W.B., Mobbs, S.F.: Radiological Impact on the UK population of industries which use or produce materials containing enhanced levels of naturally occurring radionuclides, NRPB – R327, 2001