General comments:
It is good that a compilation is made of the requirement for a geological disposal from the ICRP framework. Since the geological disposal is an area which has been discussed on international and national levels thoroughly for a long time, we feel that this report is insufficient without a proper reference and short summary of the major work done in this area and a clearly definition which role the ICRP document has in this context. Thus we are missing proper reference to the IAEA documents, OECD/NEA, Euratom as well as the leading repository programs in e.g the Sweden and Finland.
Moreover a clear definition which types of repositories are included and not are missing in the document. In Sweden we are planning repositories for high level waste (spent fuel), intermediate level waste and low level waste. All repositories are geological repositories and have long lived as well as short lived radionuclide and they are situated at different depths in the rock. Thus with the vague definitions in this document it is unclear for which of these repositories the recommendations apply for and not. Moreover from the perspective of radiological protection it seems unnecessary at all to discuss the types of repositories. It is rather the major functions which are important not the technical solution. That is
1. Radioactive substances are isolated from humans and “surface” environment sufficiently long time to reduce harm.
2. The time period is outside of reasonable institutional control.
3. The principle is to achieve this is to concentrate waste to few sites with higher potential doses for a limited exposed group than do disperse and dilute the dose to a large population.
We suggest that the recommendations concentrate on the principles for any repository fulfilling the criteria listed above instead of discussing a very specific type of repository. If this is not decision by ICRP we need very clear definitions type of repository is intended in this document. In any case the substantial work outside the world of ICRP must be referenced to, because it has a considerable impact on implementation with the same intention to protect future humans and environment which cannot be neglected. The recommendations by ICRP have been early implemented but been refined during decades by other organisations.
Moreover, several places in the document express doubts about to be able to look into the future in a scientifically acceptable way (see detailed comments below). This is an unnecessary bias in the document, if it is not rephrased shows that the authors are not updated with the current situation. Most organisations that take a serious approach on planning a repository spend considerable efforts to understand potential future conditions and explore this in a scientifically proper way, both in the rock as well at the surface. In fact in many cases they are at the front of science by considering very long time scales. We require that the document is rephrased that these sentences express that any projection of the future requires a scientific underpinning rather than the current sentences which give the impression that it is not science to project the future.
For two different subjects the recommendations get unnecessary prescriptive, maybe based on the same misunderstanding as touched in the previous comment. One subject is the recommendation of a stylised biosphere and the other is reference organisms. Instead of recommending these two shortcuts, the argumentation should be in lack of better knowledge the stylised biosphere and reference organism can be used. This is especially important if the acknowledged stakeholder participation is taken seriously. It is very difficult both to explain and defend a stylised often generalised biosphere or a set of reference organisms which are not present at the site. It only gives serious doubts of that there is any understanding of the site. We suggest that the document is rephrased all over to say the a representative biosphere should be used and in lack of better information a stylised biosphere can be used, or in lack of site data a set of reference organisms can be used.
We foresee a major revision of the document and if requested we can give further input in discussions and share facts about geological repositories.
Specific comments
# refers to line numbers presented in draft and italics are cited wording from the document, bold suggestion is what we suggest as a change in the document.
#15 Why the word solid in the title, aren’t these principles for all type of geological disposal or will there be other recommendation for non solid waste, or doesn’t ICRP recommend other waste types? Suggestion is to explain the terms used
#29 M.Westerlind instead of Vesterind ??
#176-178 Geological disposal are also Low and intermediate level repositories. This text just fits repositories with long lived spent fuel waste, but there is no definition what it the recommendations cover.
#178 It is misleading to say “changes (unspecified) are particulary slow”, it depends on what is meant, hydrology can be fast, chemical reactions fast, does it mean a constant environment? Moreover the unprecise qualifier “At great distance” open for an endless discussion. Why not reformulate the sentence starting with sentence following “With distance…..”. In addition, “geological timescales” is imprecise and difficult to evaluate. The document gives no guidance as to what timescales should be considered. See also comment #321.
#224 The scientific basis for dose and risk assessment at very long….. questionable. This is very negative sentence which is a slap in the face for the major leading organisation in this area to improve the scientific basis for the risk assessment. Especially the word questionable gives the impression that ICRP doesn’t believe in the efforts done. Suggestion to reformulate take away the word scientific and replace questionable with uncertain
#295 This definition excludes low and intermediate level long lived waste, because they will be impossible to isolate forever. But they can be isolated sufficient long time to reduce harm. Even if the high level waste can completely be isolated for long time, releases cannot be excluded and the main point is rather to isolate/retard it sufficient long time to reduce harm. Then will the definition even fit broadly, eg. intermediate level waste.
#299-#306 This paragraph includes intermediate level waste, i.e. contrary to the operative definition in the paragraph before.
#309 The planned intermediate level waste balances at the margin of several hundreds of meters.
#321-323 Unclear what are geological time scales? E.g earth quake seem to be a very quick geological event, shore line displacement in Scandinavia 0.5m/ 100 year even if the Scandinavian bedrock dates back to billions of years. Moreover this gets more confused which geological changes are particularly slow with great distance from the surface in next sentence. Well at great (??) distance we are in the geological domain and they seemed to defined slow ? Suggestion is to reformulate sentences, skip the general geological statements, go right to the point and say for time scales 1000- 1milion of year. Say it is stable chemical and mechanical stable environment with a reduced water turnover. (see also comment for line #178).
#331 No exposure is ever intended although these may happen. Depending on what exposure means it seem difficult to fulfil for intermediate and low level long lived waste since exposure will eventually occur, however after a long a time and below risk limits. Even for spent fuel it is not meaningful to make a large distinction between never and long time. Line #335 comes closer to the real function, to isolate as long as possible to reduce harm. Suggestion is to omit the sentence on line #331.
#425-#426 Unclear what near surface facilities are ? Is the geological repository SFR a near surface facility (at 50 m depth) ? It does not rely on presence of man. The interim storage for spent fuel CLAB is also a 50 m depth, but relies on presence of man. Thus the distance to surface cannot be the major distinction it must be the intended function, eg isolation and absense of man. The paragraph needs to reformulated to come away from the distance and go to function.
#587 A baseline of environmental conditions…. It is impossible to rely on a prestudy and call that baseline. Over the time periods considered it impossible to find a baseline that doesn’t vary over time. Thus “natural undisturbed” data must be monitored continuously at reference sites to make meaningful comparsions to “non natural” effect of a repository. You cannot rely on a prestudy baseline for this comparision.
#591- 592 Seems to go far beyond in detail how the repository will be operated and unnecessary to describe in this report, except that there might be parts that are closed while others are open.
#600 See comment to #587
#649 Interactions with….. the sentence is an odd addition in this paragraph, need more explanation what is meant except the obvious that it always is good to have a consensus on what your doing. Thereafter stakeholders are repeated without any clear meaning in the remaining of the text. We suggest that Stakeholder participation need its own definition and sentence if it should be included, or a more clear wording of who should participate.
#655 this paragraph (31) needs to coordinated with paragraph 29 (#616), just now to much repetition and overlap.
#693 this paragraph (35) doesn’t fit for many types of wastes in geological disposal facilities see comment #295 and #331.
#878 environmental compartment Unclear, does it mean habitat, community or ecosystem ?
#879 humans, flora and fauna suggestion to reformulate to humans or other organisms, because flora and fauna doesn’t include some of the major organismal groups or includes in a wide sense humans.
#881 evolution of the biosphere unclear, probably development or even more variation in the biosphere and not evolution (sensu Darwin) . It is recommended to use the evolution very carefully, since for most scientifically educated it suggests the evolution of organisms (sensu Darwin). The recommendation is to replace it with changes, development or variation all over the text to avoid misunderstanding. Moreover evolution in the wide sense is a directional change, which probably not the case where it is used , rather variation.
#883- #885 This is rather a questionable sentence, reformulate see comment #224
#894-#902 Unclear paragraph (49) especially sentence starting #899 Situations of this kind… wording to vague to understand what the purpose is. Is the meaning that future generations need to take their own responsibility to manage the waste in a proper way?
#910- #920 Vague paragraph (51) with a vague recommendation and unclear wording. Tectonic events how do they differ from earth-quakes in the preceeding paragraph. Aren’t earth quakes an tectonic event, what else is tectonic events ?. Moreover a major landform change is shore line displacement, a quite dramatic change in the near future potentially already affecting the operation of a facility. There is a good scientific basis to discuss this event and give probabilities. I get the impression because this is outside the knowledge of the authors, the paragraph is vague. The recommendation is either to omit the paragraph or review the programs of the leading organisation to include more appropriate facts and reality, why not include the operators to give more information in this area and work out a more useful recommendation
#921- #938 This paragraph (52) is hard to understand. … .. separate consideration of natural disruptive events which are included in the designbasis evolution …. Undefined wording, why evolution?. The separation between the event and how it is handled is purely hypothetic and not possible to do in reality in the safety assessment in a clear cut way. Thus the separation will be arbitrary with an endless discussion which finally doesn’t matter in practice. It seems more to force the semantics of ICRP in the handling, than provide any meaningful guidance.
#939- #949 Paragraph (53) and paragraph (54) suffers from the problems in the preceeding (52) paragraph, see #921. If that is not cleared out these paragraph are problematic.
#972 While the ….. a confusing and unnecessary sentence , omit it to make the following sentence much clearer.
#981-985 It not correct to say there is no scientific basis (see comments #224, #883) , there is plenty of basis to say what humans likely can do in future, thus predicting the nature and thus also set the probability of zero for many cases is doable, while given any other number is as uncertain than many other cases contained in the safety assessment. However, the message can still be that it is sufficient to illustrate the intrusion rather than to make long calculations on this. The suggestion is to exclude the part of the sentence on line #981-982.
#1004 This table suffers from unclear meaning of concepts as well hypothetical classifications which are not feasible to distinguish in a real case of a safety assessment. Thus more forcing the ICRP semantics rather than to provide practical guidance. See comment to #921, #939 and #981.
#1053 Some important features of the repository are missing, which should have its own consideration, that is safety guards to prevent nuclear proliferation, HELCOM and OSPAR conventions which are all realities that need to be considered. Some of them directly constraining the siting and construction. We suggest that at least this is mentioned in the text.
#1061 There is no example or explanation how a stepwise process and milestones can be considered, thus difficult to see how this can be implemented. Suggestion is to shoe how this can be implemented with an example.
#1179…1194 In this paragraph (80) the keyword from ICRP (101) sustainable is missing. It is important to realise that sustainable use of the environment is the important way to obtain lifetime doses of significance. The sustainable use also maximises the long-term exposure. But there are also environmental constraints on the humans how they can utilise the environment in a sustainable way. Suggestion is to put the word back from ICRP 101, or motivate why it has been taken out.
#1184 Unclear what is meant by stylised. In any case the current safety assessment by SKB and POSIVA, the representative person obtains it features from a reasonable (sustainable) utilisation of its environment. That means not a stylised or generalised reference biosphere at least not in the sense the IAEA Biomass program has discussed it. Suggestion is to define the term and suggest it as an alternative not as recommendation, because the currently most detailed programs don’t use it because it doesn’t provide any meaningful help.
#1198 - #1202 This part is unclear. Does it mean that in spite of that the site is covered by the sea, 300m permafrost or 2000 m of ice it is postulated that humans will a receive a dose from a drilled well? We can do better than that and we need to do it, if we want that stakeholders will accept the work we are doing. Suggestion is to clarify this or omit the part.
#1211- #1213 A stylised biosphere can be used as a first step when no data are available. But during the site investigation sufficient data are collected to fulfil the needs for the EIA and baseline. Thus a site specific biosphere will always be possible to obtain and will be far more convincing for stakeholders than an abstract non representative “stylised” biosphere. As ICRP points out the role of risk estimate is obtain a comparison over long time of the repository behaviour. To obtain this with good confidence it is better to stick to a realistic site specific biosphere instead of suddenly introduce a generalised biosphere which has several orders of unexplainable variation in parameter values and shifts the comparison value to another direction just by change of methodology. Suggestion is to rephrase the section that Stylised biospheres can be used in lack of site data
#1215- #1228 The recommendation of this paragraph is unclear. An assessment with age groups or not? For the sake of simplicity and as ICRP has pointed out several times in this document that there are uncertainties about the future and the risk estimates are just indictors of harm. This is also contradictory to ICRP 101. The only reasonable recommendation would be to estimate average life time risk, not dose to different age groups.. Suggestion is to omit age groups, it doesn’t improve the assessment in any way. Otherwise it must be an argumentation for why the far future requires a higher complexity than recommended in ICRP 101.
#1242- #1243 Suggestion is to replace fauna and flora with organisms to include all kinds of life not a subset.
#1251- #1270 The ICRP recommendation for the use of reference organism is not mature for geological disposal. As shown by NHB workshops by BIOPROTA, several concepts for reference organisms are misleading when concerning a very long time risk for a population which is exposed to a point source. The parameters (eg CR) collected for reference organisms assume an even contamination (i.e a Chernobyl accident) and not point sources from a facility. Moreover the knowledge from a potential site for geological repository will be quite high due to the demands for the EIA, monitoring and baseline estimates. Thus the real organisms at a site are known and far better to use in discussion with stakeholders, than with abstract non site existent reference organisms which even for experts in diversity and ecology have unclear meaning.
Suggestion is that the recommendation by ICRP describes reference organisms as one alternative to illustrate consequences to the environment beside using site specific organisms. It is better to replace the reference organism with representative organism all through the recommendation. Representative includes reference in lack of better alternatives.
#1264- #1265 biosphere evolution is directly misleading here, we assume it is not evolution of organisms, it is variation or changes (see #881)
#1269 as pointed out in #1242 , animals and plants are a subset of life. Suggestion is to replace reference animals and plants with representative organisms instead to cover the message in a more general way.