Dear sir/madam
Thank you very much for giving us the opportunity to review the ICRP draft document "Radiological protection in Surface and Near-Surface Disposal of Solid Radioactive Waste". The comments in the pdf file attached are from the Environment Agency (England and Wales) and should be considered complementry to those sent by Richard McLeod on behalf of the Scottish Environment Protection Agency.
In addtion, the UK Health Security Agency (formerly National Radiological Protection Board) would like to make the following comments:
"The UK Health Security Agency (UKHSA) fully endorses the response provided by the Scottish Environment Protection Agency (SEPA) and the Environment Agency (EA) on the ICRP draft publication: “Radiological protection in Surface and Near-Surface Disposal of Solid Radioactive Waste”. We believe that the document would benefit from further editorial work to improve clarity and consistency and agrees that the comments made by SEPA and the EA would help greatly to achieve this outcome.
In particular the UKHSA supports the comments made by SEPA and the EA in relation to Table 1. We have found that the table is difficult to interpret and that there are inconsistencies between the information contained in the table and that provided in the text. In addition to the comments made by SEPA and the EA we note that Table 1 appears to indicate that BAT should be used in the post-closure phase in relation to extreme events and accidents and that it should be “Not considered in optimisation”. This is incorrect and inconsistent with the text in Section 3.5 “Optimisation of protection”.
In relation to optimisation, Section 3.5 “Optimisation of protection” provides a lot of useful information; however we believe that that there should be more emphasis in this section on the use of dose and risk constraints as key tools to guide optimisation, both for occupational and public exposures. Although dose and risk constraints are mentioned throughout the document and “selection of an appropriate value for the constraint or reference level” is listed as one of the steps that needs to be taken in the optimisation process, Section 3.5 does not deal in sufficient detail with the scope and objectives of assessing doses and risks in the optimisation process for comparison with dose and risk constraints (eg setting discharge and disposal limits). It would also be beneficial to discuss the differences between dose constraints occupational and public exposure, not just risk constraints, as well as reminding readers of the difference between dose limits and dose constraints. We also note that the ICRP draft publication: “Radiological protection in Surface and Near-Surface Disposal of Solid Radioactive Waste” does not mention collective dose as a tool for optimisation. ICRP Publication 77 included and entire sub section (Section 6.2.2) on the use of collective doses in waste disposal indicating in paragraph 50 that “Collective dose plays a limited but important role in the application of the Commission’s system of protection to waste disposal”. It would be useful to know what the current advice from ICRP is on the use of collective doses in the optimisation process for disposal of radioactive waste.
Finally on the topic of protection of the environment, we fully agree with the comment made by SEPA that DCRLs are analogous to the dose constraints applicable to exposures of people in normal exposure situations and that there is no clarity in ICRP’s publications on whether they should be applied to potential exposures. We also note that the main objective of assessing doses in emergency exposure situations is to establish what countermeasures (ie sheltering, evacuation and administration of stable iodine) should be applied and it is not clear what role assessment of doses to animals and plants would play in this process. We therefore agree with SEPA’s comment that this section would benefit from ICRP clearly setting out its recommendations on this matter."
Best regards
Tiberio Cabianca, UKHSA, 7 April 2023
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