Refresher course 2C

Topic:
A regulators perspective on the assessment of environmental NORM risk

Lecturer(s):
Cameron Lawrence (Australian Radiation Protection and Nuclear Safety Agency –ARPANSA-, Australia)

Learning objectives of the refresher course:
During this course it is expected that the attendees will learn:

  • Range, benefits, and limitations of environmental modelling tools for NORM
  • Impact that varying assumptions can have on the outcome
  • Evaluating the results of NORM environmental assessments
  • Australian approach to NORM environmental assessments

Summary:
The aim of this training course is to provide a regulatory view of the assessment of models available that can be used to assess environmental NORM risks. It is critical when performing or evaluating environmental risk assessments that the justification for the underlying assumptions used are well understood. Knowing how the assessment tool performs is essential to ensuring that the results are valid. Assuming that the “black box” of the assessment tool will provide you with all you need can lead to errors, both user and evaluator need to know how it works. In most cases a few runs using one or more models under varying assumptions should be performed and the boundary results provided for evaluation.

In Australia the regulatory approach is not to be prescriptive in the modelling that a proponent must apply to their safety case. Instead, it is up to the proponent to justify the assumptions and conclusions they have applied and drawn from the modelling that they have chosen for the work they are proposing. While the use of known and proven modelling tools is preferred and can make the evaluation a simple exercise if a case presented uses less complex modelling it should be assessed on its merits if it is fit for purpose. In some cases, the initial assessments using simple modelling might indicate that further detailed modelling is not needed and that should be support in a graded approach regulatory framework.

This course will look at a range of model types and compare some of the work performed by the MODARIA II Working Group 1 looking at the benefits and limitations of the models that they evaluated. Some case studies from Australia will also be presented and reviewed from a regulatory perspective.

List of recommended (pre)reading literature:

  1. ARPANSA, 2015, Guide for Radiation Protection of the Environment, Radiation Protection Series G-1 (RPS G-1)
  2. ARPANSA, 2018, Code for Disposal Facilities for Solid Radioactive Waste, Radiation Protection Series C-3 (RPS C-3)
  3. ARPANSA, 2008, Code of Practice and Safety Guide for Radiation Protection and Radioactive Waste Management in Mining and Mineral Processing, Radiation Protection Series 9 (RPS 9)
  4. INTERNATIONAL ATOMIC ENERGY AGENCY, Disposal of Radioactive Waste, Specific Safety Requirements 5 (SSR-5), Vienna (2011)
  5. INTERNATIONAL ATOMIC ENERGY AGENCY, Management of NORM Residues, TECDOC No. 1712, Vienna (2013)
  6. INTERNATIONAL ATOMIC ENERGY AGENCY, Radiation Protection and Management of NORM Residues in the Phosphate Industry, Safety Reports Series No. 78 (SRS-78), Vienna (2013)
  7. INTERNATIONAL ATOMIC ENERGY AGENCY, Radiation Protection and NORM Residue Management in the Zircon and Zirconia Industries, Safety Report Series No. 51 (SRS-51), Vienna (2007)
  8. INTERNATIONAL ATOMIC ENERGY AGENCY, Radiation Protection and NORM Residue Management in the Titanium Dioxide and Related Industries, Safety Report Series No. 76 (SRS-76), Vienna (2012)
  9. INTERNATIONAL ATOMIC ENERGY AGENCY, Radiation Protection and NORM Residue Management in the Production of Rare Earths from Thorium Containing Minerals, Safety Report Series No. 68 (SRS-68), Vienna (2011)
  10. INTERNATIONAL ATOMIC ENERGY AGENCY, Management of Residues Containing Naturally Occurring Radioactive Material from Uranium Production and Other Activities, Specific Safety Guide No. 60 (SSG-60), Vienna (2021)