Comments by the Belgian Federal Agency for Nuclear Control (FANC) to the draft ICRP document “Radiological Protection from Naturally Occurring Radioactive Material (NORM) in Industrial Processes”.
A. General remarks:
As a regulator, FANC appreciates especially the facts that:
These two important statements are in line with our daily experience in regulating NORM activities.
Some other statements in the draft document may require some nuance according to the following remarks:
1) Existing vs planned exposure situation
We acknowledge that ICRP considers NORM activities as existing exposure situations with valuable and justified arguments. This allows for a consistency of approaches for exposure to different sources of natural radiation: radon, NORM in industries, NORM in building materials (see e.g. line 306). However, e.g. in current European regulations (EU directive 2013/59/euratom), NORM activities are rather considered as planned exposure situations (while, in the same directive, NORM in building material are considered as existing exposure). This may lead to confusion among the stakeholders. Although the practical implementation of both points of view (existing versus planned) will probably not be so much different (in both cases, the first step is an assessment of the exposure and, according to the results of this assessment, the choice of appropriate protective actions), some clarification or recommendations (for instance, an additional explanatory paragraph in Section 3.1) may be needed on how to reconcile both points of view in practice.
2) Protection of the environment
While it is appreciated that the issue of impact of NORM activities on the environment is addressed, there is some inconsistency in the document between the approach towards protection of workers and public and the approach towards protection of the environment. For workers and public, the document rightly advocates the use of graded-approach and of integration of radiation protection aspects within a global approach of radiological and non radiological hazards. On the other hand, the recommendations regarding approach towards environment systematically refers to the need of performing an Environmental Impact Assessment (EIA) including radionuclides. In §130, the document goes even further by stating “it is necessary to perform the site-specific analysis of radionuclides with respect to their physical and chemical forms… it is further necessary to identify the mobility of radionuclides, their spatial and temporal variation, etc.". Such a statement is not consistent with a graded-approach, which in the same draft recommendations is recommended regarding the exposure of workers and public. The approach towards environment proposed in the draft does not take into account the diversity of NORM situations which is acknowledged in other parts of the draft: the impact on the environment for a ceramic factory should not be addressed in the same way as for a large tailings disposal site.
Characterization of exposure (of workers, public and environment) itself is a graded process: in many cases, the risk of significant exposure may be discarded on basis of a simple screening based on "rules of thumb" or intuitive arguments without performing a detailed assessment. Even when the radiological risk can not be straightforwardly ruled out, characterization or control mechanisms implemented for the control of non radioactive hazards may in some circumstances be considered as being sufficient for the protection against radiological hazards (as it is said in the draft document regarding exposure of workers).
A regulator needs to think about the protection of the environment but should be left the freedom to choose the most appropriate means to assess risk. It is not always necessary to systematically add the radiological parameters in the EIA; alternatively, one can e.g.:
Moreover, the protection of the environment is almost only addressed in the draft document on basis of environmental reference level: here also, the need for protective actions should be judged holistically in an integrated approach of the different hazards: it is for instance unlikely that the radiological impact of a NORM activity would engender more damages to the non-human biota than the direct consequences related to a large industrial activity (such as deforestation). Moreover, the principle of doing more good than harm should be kept in mind: this is especially true in the approach of legacy sites where remedial actions may sometimes cause much more damage to the environment (by destroying specific biota) than leaving a contamination in place.
3) NORM and radon
The statement (§ 68) that radon and thoron in the workplace should be managed as a single source clarifies a long discussion about whether or not include the contribution of radon in the dose-assessment of a given NORM activity. However (see § 14), means of control may sometimes be different for radon related to NORM activities as, in some cases, a control on the source could be possible (thus, not only “management of building and locations…” as stated on line 239); e.g. for legacy sites, risks of exposure to radon may be dealt with through remediation measures (excavating and disposing properly the radium contaminated soil).
4) NORM in drinking water
The draft document does not mention the issue of NORM in drinking water. It is actually not clear if this issue is within or out of the scope of the document. Natural nuclides in drinking water may be considered as part of the geological background but drinking water may as well be considered as the end-product of an industrial activity (water treatment). Some remark in the document about this aspect would be helpful. The issue of NORM in drinking water could be tackled similarly as other NORM aspects: assessment of the risks and justification of protective measures (doing more good than harm). This is especially true for countries where drinking water supplies are scarce.
B. Specific remarks:
1. Line 45: remove the word “accidental” – not only accidental but also routine releases which are not appropriately controlled may result in detrimental effects;
2. Lines 313-318 (§23): this categorization of “scenarios” for radiation exposure is odd and confusing. It is not clear what is meant here. There is indeed a distinction to be made between large quantities of material (not only ore or raw material stockpile but mainly heap of large amounts of NORM residues, such as tailings disposal sites or phosphogypsum stacks) and moderate/small amount of material with a relatively higher activity concentrations (scales,...). But the “volatised” material is just a particular case and is not really a category of exposure scenario as such: these materials may also be in small quantities (such as deposit within a coal-fired power plant) or in large quantities (heap of slags or fly ashes). A distinction between patterns of exposure could rather be made on basis of exposure pathways within the respective sections on workers exposure (e.g. routine processing of NORM material versus exposure during maintenance operations) and on public exposure (e.g. scenario related to liquid or atmospheric discharges, to public use of legacy site, to the incorporation of NORM in consumer products such as building materials).
3. Lines 371-372: to single out phosphogypsum as the only example of public dose higher than 1 mSv is not correct. For instance, Table 34 of (IAEA 2011 [1] ) provides estimation of public exposure related to heavy-mineral sand mining in India : they range between 3 and 17 mSv/a. In the same report, reference is made to the uncontrolled use of such type of sand as building material leading to a gamma dose of 16 mSv.
The example cited about phosphogypsum is a theoretical estimation which does not reflect real building practices. The statement gives a misleading idea that use of phosphogypsum as building material is systematically a source of significant public exposure (while in practice activity concentration in phosphogypsum covers a significant range and does not necessarily imply an increased risk of exposure compared to other building material (see IAEA 2013 [2] § 10.5.2). Use of other building materials such as e.g. alum-shale may lead to dose above 1 mSv.
4. Lines 383-384: see generic remark on Protection of the environment – add e.g. “taking into account graded-approach in the evaluation process”
5. Line 467: “releases and discharges may result in environmental damage and public exposure”
6. Lines 506-507: see generic remark about EIA – delete “starting with an EIA considering the presence of NORM”
7. Line 519 : a possible exception is the incorporation of NORM in some consumer goods.
8. Line 572: see generic remark – to integrate radiological impact in EIA is not always relevant
9. Lines 673-674: Protection is generally achieved in practice by a combination of collective and individual protection measures. The choice of the most appropriate protection measures is made on basis of a cost-benefit analysis taking into account prevailing circumstances. Use of PPEs is generally cheaper and can often be implemented quicker than collective measures.
Same remark for line 763-764: the statement is correct if it refers to dosimetric follow-up; monitoring of dose at the workplace is in most cases sufficient (if at all necessary) and individual dosimetric follow-up is only rarely needed. But regarding protection equipment, PPEs are generally not more costly than collective protective equipment (such as a dust extractor).
10. Lines 676-681 (§66) : see remark 2)
11. Lines 787-788 : the statement is correct to assess actual exposure and define the need for any additional protective measures. But a worst-case assessment without taking into account existing OHS provisions may be useful in a regulatory process as it gives an idea of the possible dose in case of failure of OHS control (for instance, in some circumstances, a worker may not wear his/her PPEs for personal convenience – even if it is required by OHS provisions). Such a worst-case assessment may provide useful information to define e.g. the stringency of the enforcement policy regarding OHS (especially taking into account the fact that OHS regulator is not necessarily the same as the radiation protection regulator).
12. Lines 814-817: as mentioned in the text, replacing the raw material by an alternative material with a lower activity concentration is often not possible as the choice of raw material depends on many other factors than radiation protection. One should also be cautious when promoting the use of material with a lower activity concentration: such a choice should be dependent of an analysis of the integrated impact of the alternative material. An alternative material may have lower activity concentration but may present other hazards, e.g. it may be more dusty and imply a higher exposure to fine dust. Here also the search of alternative material should be based on the principle of “doing more good than harm”.
13. Lines 870-871: it is not clear what is meant here: how PPE could lead to an increase of the exposure ? See also remark 9.
14. Section 4.2 “Protection of the public” : As for workers exposure, an integrated hazard management could be recommended. The assessment of a need of a protection strategy may take into account the control measures already implemented for the control or monitoring of non radiological hazards.
15. Lines 1052-1053 “Technologies and methods already exist and should be implemented in order to avoid legacy sites”. This statement is quite vague and its meaning unclear. This implementation can only be done during operations. The statement rather pertains to the section on workers, public and environment exposure: assessment of the risk of exposure needs also a consideration of the scenario related to the dismantling of the NORM facility or the post-closure phase of a disposal site. But this must be part of the risk-assessment of an existing facility; when it is already a legacy, it is too late to implement these prevention measures.
16. Line 1072: “The challenge may also be due to a lack of societal acceptance”. Although we agree that social acceptance has to be taken into account in the decision-making process regarding legacy sites, the meaning of this statement is unclear: acceptance of what ? Of the legacy itself ? Of the remedial actions proposed ?
17. Line 1075 (§124): This is not consistent with §99. In remediation as well, the risk of exposure of the workers needs to be assessed but they need to be considered as occupationally exposed only if – as said in §99 - “despite all reasonable efforts to reduce exposure, elevated individual doses persist…”
18. §130 – see generic comment on Section 4.3 – there is a need to take into account variability and diversity of situations. This § should best be removed.
19. Line 1144 – “When dealing with NORM discharges and disposal …”
20. Line 1381-1382 “32000 tons of uranium and 80000 tons of thorium can be considered as being extracted as well” : although we understand that this statement is for illustration only, we find this statement quite naïve and possibly misleading. One can say the same for any raw material (sand, limestone, clay …) or soil extracted in massive quantities. Uranium and thorium “extracted” with coal or any other raw material are not available as such for processing. Maybe add some mitigating sentence such as “The same is true for any raw material extracted in massive quantities”.
21. Line 1400 – in some cases, concentration of uranium in ion-exchange resins may be considerably higher.
22. Line 1519-1523 (definition of NORM) – why is this definition different from the one of IAEA Safety Glossary ? Especially, the sentence “… in which the activity concentrations of the naturally occurring radionuclides have been changed by some process…” is confusing. This definition of NORM is restricted to what was formerly designated as TeNORM – while the draft recommendations also refer to undisturbed material such as ore.
23. Line 1580-1583 (definition of residue) – here also it would be clearer if a consistent terminology with IAEA Safety Glossary would be followed (i.e. NORM residue = material that remains from a process and comprises or is contaminated by NORM). Residue is what is left from a process : it may be reused or recycled and not necessarily “remain in the environment”. In general, we would recommend to check the consistency of the definitions proposed in the Glossary of the draft document with commonly accepted definitions.
[1] IAEA, SRS68, Radiation Protection and NORM Residue Management in the Production of Rare Earths from Thorium Containing Minerals.
[2] IAEA, SRS78, Radiation Protection and NORM Residue Management in the Phosphate Industry