Nuclear Polluters' Charter Part II

LLRC response to UK Government consultation
continued


Below we reproduce the remainder of the text of LLRC's response to the Department of the Environment, Transport and the Regions' consultation on transposing those parts of the European Council Directive 96/29/Euratom which affect the UK's Radioactive Substances Act 1993.
see this link for Part I


PART 4
re Part 2 of DETR Consultation Document
"issues on which comment is sought"

1) Natural vs man-made (para 38 - 43)
There is a need to distinguish between isotopes not solely on the basis of whether they are natural or man-made but on the basis of their observed health effects. Regard must also be paid to the existence of genetic repair mechanisms which cope with radiation damage at natural background rates, and to the possibility that some natural isotopes used in artificial processes may come to be present in concentrations high enough to overwhelm our capacity for genetic repair. The tragedy of the radium dial painters is by no means the only example. We recommend retaining the distinction between natural and man-made in paras. 39 and 40 We recommend retaining the Schedule 1 values for Natural isotopes. We recommend retaining the principle of SoLA exemption orders (para 41 & 42)


2) para 42: The statement that "... there is no difference in the nature of radioactivity or radiation dose whether it arises from natural or artificial sources" is false. The quality of radiation varies widely - variations are already crudely incorporated into the conventional model in the form of Relative Biological Effectiveness (RBE) factors ; the "nature of ... radiation dose" is more questionable. The very applicability of the concept to low level hazard is under severe criticism. We would discard the average energy transfer model and replace it with a measure of the extent to which any given exposure would increase the number of radiation tracks likely to intercept any cell above the baseline NBR rate of one track per cell per year. This would be qualified by

a)        isotope specific factors based on decay rate and decay pathway, thus taking account of the likelihood that overlapping tracks would interrupt the genetic repair cycle;

b)      factors accounting for any propensity of particular isotopes, especially those with sequential decay pathways, to become biologically bound or immobilised;

c)      factors based on any prevalence of hot particles which might deliver chronic local doses to tissue in which they lodged;

d)     factors for decay energy.

We are not happy about the idea of modifying of SoLA exemption orders "as necessary" (para.42). The question always is whether a modification is made to accommodate the needs of the industry or whether it is done to protect the public. We recommend that any modification of SoLA values should be the subject of public consultation.

3) Paras 44 - 47
Agreed


4) Paras 48 to 52 Radioactive material outside regulatory control

The exposure scenarios and dose calculations used to derive the proposed Clearance Levels are an exercise in seeing the trees and ignoring the size of the wood - or is it a forest?

One problem is the absence of any calculation or allowance for the total inventory of radioactivity eligible for Clearance or the rate at which it is expected to be cleared.

A second is that over a number of years radioactively contaminated materials will rust and wear, and will be reworked and recycled over and over again. This process of progressive disintegration will allow radioactive dust to spread generally through the environment. It will be inhaled, ingested and absorbed, and internal doses will increase.

Moreover, a number of recently discovered and as yet poorly described mechanisms which need further research will cause some of the radioactivity to reconcentrate, potentially increasing exposure to people in certain locations and with particular habits. Examples are the increasing levels of Tc-99 in lobsters and seaweed, radioactive pigeons at Sellafield, electrostatic adsorption onto dust, onshore migration of plutonium, non-uniform distribution of radioactivity in marine sediments, and the fact that 40% of the plutonium known to have been discharged from Sellafield into the Irish Sea cannot be accounted for [Kershaw 1999]. To these must be added bioconcentration mechanisms such as the discovery of plutonium in children's teeth [Priest 1997] and the extreme affinity of plutonium for pulmonary lymph nodes [McKinroy 1991].

To take account of these exposures it would be necessary to integrate doses over many years. The Collective Dose calculations in DETR/RAS paras. 5.3 are fatally inadequate; they cover only the lifespan of the artefacts considered (15 years for a car, 20 years for a cooking pan, 50 years for an apartment block and so on), ignoring the subsequent incarnations of the materials.

The inevitable generalised distribution of radioactivity renders highly unreliable the assumption that it is not necessary to sum collective doses over the different scenarios and Clearance practices [DETR/RAS para. 5.5]

Clearance as envisaged in the Consultation document would lead to a steady year on year increase in radioactivity released from regulatory control. In the current state of ignorance of radiobiology this would be irresponsible.

We recommend that estimates should be published in the next Consultation for the following entities: a. the amount of radioactivity (expressed in total Becquerels) contained in existing materials eligible for Clearance at the levels proposed in the Consultation document, b. the rate at which it is expected to be Cleared c. the amount of radioactivity contained in or released from materials eligible for Clearance, integrated at ten year intervals over the next 500 years. d. Collective doses and health outcomes over the next 500 years from (c) above


5) Inadequacy of modelling for alpha emitters [DETR/RAS/98.004para 6.2 last subpara]

Proposed SoLA / Clearance levels for alpha emitters are more permissive than the present SoLA value. False reasoning and a lamentable lack of caution make this unacceptable. DETR/RAS para 6.2 last subpara. says:

"The exceptions to th[e] pattern of [Clearance Levels being one or two orders of magnitude lower than the Directive's Exemption Values] ... are the alpha emitters, for which the IRRrev levels [i.e. Exemption Values] are equal to the clearance levels. This is because the limiting exposure pathway for these radionuclides is often inhalation of dust, and doses via this pathway tend to be less dependent on the quantity of material considered than on the assumed dust level in air from handling the material...."
It is very unsafe to assume that increasing releases of Plutonium will not increase levels of dust. The electrical charge accumulating on a particle of such alpha emitting isotopes creates a mechanism by which the earth's electric field can resuspend the particle. The consequences of this mechanism still need full investigation, but such an inquiry has the capacity to explain undisputed phenomena such as the linear relationship between the amount of plutonium in children's teeth and the distance of their homes from Sellafield [Priest 1997], the inland migration of plutonium ' [Eakins 1984 and Eakins 1984a], and the inability of MAFF to account for 40% of the plutonium known to have been discharged to the Irish Sea [Kershaw 1999]
The German approach, which is between 11 and 25 times more conservative (i.e. restrictive) than DETR's, is more realistic. SSK1998 recommends [para 4.1] that:
"In the case of actinides the use made of the slag into which these nuclides pass when the scrap is melted down has proved to be dose determining."
The DETR consultation document's reply [para 52] is bizarre:-
"The scenario used by SSK to derive these clearance levels is very conservative and is not applicable to the recycling, reuse or disposal of large quantities of materials in the UK"
There is no reason why it should not be directly applied, and all the more so if the quantities of materials are large. The less cautious approach used by DETR must be fully explained and justified.

We recommend that wherever there is disagreement between authorities on such issues the more cautious reasoning should prevail. If Clearance of actinides is to be allowed at all, the SSK values should be adopted.


6) Paras 65 to 73 SoLA EO

Para 68 discusses the new "radiological criteria for exemption and clearance". As we point out elsewhere in this response, the principles or dogmas under which this has been done are unsafe and in some cases irrelevant. A most serious shortcoming is their failure to recognise local dose amplification effects due to sequential decays of some nuclides, hot particles and low energy emitters such as Tritium whose atoms may be present in large numbers (thus increasing the likelihood of overlapping tracks) without triggering concern in the minds of regulators with conventional views of radiation dose.

We recommend retaining the existing SoLA 0.4Bq/g non-isotope-specific value as a pragmatic and temporary (i.e. pending further research) limit for artificial radioactivity below which substances could be regarded as not being radioactive except that

for the nuclides marked with "+" in Table A of Annex 1 of the Directive the value should be 0.001 Bq/g, on account of the sequential decay pathway of local dose amplification;

for any Group 1 nuclides not marked with "+" the value should be 0.1 Bq/g. SoLA should not apply to materials which are under regulatory control and are contaminated with any level of artificial radioactivity. These should not be released from regulatory control on account of the large inventories of radioactivity involved.

See also our comments (para 10) under "Grouping of Radionuclides".

7) Disposal of radioactive substances from undertakings which are exempt from reporting and authorisation requirements under Directive 96/29 Article 3.2.

a) The following remarks repeat much of what we have said in Part 2 about Clearance. We make no apology for this.

LLRC recognise that IRR(rev) is at an advanced stage and that we have conditionally withdrawn our objection to the principle of exemption on the grounds that HMG intends to control disposal from exempt undertakings under RSA. However, a major problem with the DETR consultation document is that it uses the SoLA concept to confound Clearance with the different issue of disposal from supposedly small undertakings. The issue of scale is vital, in view of the uncertainties of radiation protection at low dose. DETR ought to have kept Clearance and Exempt disposal quite separate.

b) Exemption from reporting and authorisation is and was intended for undertakings using small quantities of radioactivity. Limited quantities of 1 tonne are the upper limit of this assumption [see background documents such as Radiation Protection 65 para 5] This is not to be seen in the Directive as adopted, nor in IRR(rev) [see Article 3.2 a) and b) of the Directive and its analogue IRR(rev) Schedule 1.1.a) and b), which are alternative, rather than additional, conditions].
Contrary to the suggestion DETR makes in para 22, the Exemption values were devised with an eye to public doses - there is extensive analysis of public exposures, mainly from landfill disposal. It is clear from the calculations that the amounts of radioactivity under consideration were so small that the authors felt they could ignore collective dose. [RP 65 para 3.2]. For this reason it is of concern that the RSA and IRR revs as proposed contain no limit on the amount of radioactivity an Exempt undertaking may use. [It should be noted that in responding to the IRR revs in 1998 this Campaign recommended that Exemption should be available to undertakings which comply with both 1.a) and b) of Schedule 1, rather than with either one or the other.]

c) A further weakness of the SoLA principle is the absence of any time qualification. It needs to be qualified so as to set a maximum amount of radioactivity / material disposed of per year.

d) Moreover it should be noted that IRR(revs) specifically sets out to allow licensed sites not to account for radioactive substances which are below the threshold values for Exemption. This is another fudge; it extends the concept of Exempting an undertaking to Exempting the substance or material, and implements the dangerous notion that the quantity of radioactivity can be disregarded so long as concentrations are below the thresholds. (This, to repeat, is foreign to the principles which guided the setting of Exemption Values.) It creates an unacceptable loss of public knowledge of the total amounts of radioactivity released to the environment.

We strongly recommend that in revising RSA it is advisable to take due account of the 1 tonne limit implicit in the Exemption Values and to incorporate into RSA a means of limiting the gross amount of radioactivity that could be disposed of from exempt undertakings.

We recommend the adoption of a system of accounting for the total amount of radioactivity used and disposed of from Exempt undertakings in any given time period.

We recommend that DETR should draft such a measure for inclusion in the next consultation.


8) Dilution to achieve SoLA values

There is no provision in the Directive, in IRR(rev), nor in the Consultation document to prevent radioactive substances being diluted in order to bring them below SoLA values. We have been assured by the Minister for the Environment that such dilution will not be allowed, but this principle needs to be explicitly incorporated in law.

We recommend that any revision of RSA must clearly and explicitly preclude dilution to achieve SoLA values.


9) Dilution to achieve Clearance Levels

The Directive does not preclude diluting contaminated materials which are under regulatory control in order to achieve Clearance Levels. Anecdotal evidence suggests that operators in at least one Member State are purchasing clean scrap, mixing it with contaminated scrap, smelting it, and selling on the product. European Commission Guidance on recycling metals [Radiation Protection 89] has been published and recommends [para. 3.1.vi; para. 5] that dilution to achieve clearance should not be allowed. Guidance on other materials is not yet published. Such Guidance appears to have little legal force, in view of the incentives decommissioning contractors will have for minimising volumes of waste which will have to remain under regulatory control and in view of the nuclear industry's poor reputation in handling waste. The EC has assured LLRC that a Court of law would take its Guidance into account if an apparent breach were prosecuted, but the Guidance is so worded that it puts the responsibility for preventing deliberate dilution on the government of the Member State, not on the contractor or operator. We recommend that if any Clearance of contaminated materials is to be permitted the "no dilution" provision should be incorporated explicitly in law. The duty of compliance must rest on the operator.


10) Grouping of radionuclides [para 70]

Notwithstanding our objection to the principle of Clearance and to the levels of activity proposed as Clearance Levels, we are with one substantial reservation in broad agreement with the grouping of nuclides. The reservation is that there should be a further Group comprising the nuclides marked with "+" in Table A of Annex 1 of the Directive. This is because the decay rate of the daughter isotopes potentially create second event effects. A prime example is Strontium-90, with its well documented genetic effects (e.g. work by Luning, Stokke, Ehrenberg, Busby), and the ease with which it is transferred from soil into vegetables (Note that Sr-90 will not differentiate between home grown and commercially grown crops, and that transfer into forage crops and thence into meat and dairy foods is an important consideration for human health).

There are also some inconsistencies which need correction, for example

*    Yttrium-90 should not be in Group III: Y-90 is not a weak b emitter but a strong one;

*     Omission of radioactive gases from consultation. Some radioactive gases have the capacity to be absorbed by other materials. It is therefore necessary to include those gases in considering whether to allow contaminated materials to be Cleared for reuse, recycling or disposal. The Consultation document's Appendix 2, setting out proposed levels for unconditional clearance of contaminated materials, claims to apply to "all man-made radionuclides..." Table 5 (p.104). It omits a whole range of reactor noble gases e.g.Ar-41 and any of the isotopes of Krypton. These omissions require explanation.

*     The radioiodines are apart from I-125 are also missing.

*     Tritium H3 has unique qualities as a radiological hazard since it is so easily incorporated and exchanged in biological tissue. There are a number of questions outstanding over the present belief, shown in this table that it is a low level hazard because of its small decay energy. Indeed for this very reason, a large number of decays make up a Sievert dose and this increases the possibility of second event damage to cells. Furthermore, there is a hazard resulting from transmutation of the Tritium atom to Helium, especially in molecules such as enzymes . This has yet to be addressed by the radiological community, but as it demonstrates a mechanism by which the decay of single atoms could alter the reactivity of massive molecules associated with critical biological processes it obviously represents an enhancement of risk many orders of magnitude greater than predicted by the conventional energy transfer model. For these reasons Tritium should be included in the 0.4 Bq/Gg group.

*     Pu-241 decays to Am 241 which is an alpha emitter and not therefore a low hazard. It should be in the 0.4 Bq/g group.


11) SoLA (Para 73)

a) "Should the SoLA level of 0.4 Bq/g for solid materials be changed?"

There should be no increase. For the nuclides marked with "+" in Table A of Annex 1 of the Directive the value should be 0.001 Bq/g, on account of the sequential decay pathway of local dose amplification ; for any Group 1 nuclides not marked with "+" the value should be 0.1 Bq/g.

b) " ... any clarification required on the application ...?"

Giving SoLA value(s) as averages is inadequate. There must be a measure to prevent the release of hot particles.

We recommend that SoLA exemption should apply to for small undertakings, excluding Clearance, for disposal of substances where activity is averaged over 1 tonne of material but where there is no inhomogeneity at any level greater than 10-fold;
Because of local dose amplification caused by hot particles the material disposed of must not contain particles giving more than 2 decays of 50 KeV or more per 10 hours.

Secondly, a weakness of the SoLA principle has been the absence of any time qualification. See our paragraph 7c on SoLA disposal from Exempt undertakings


12) Conditional exemption orders [paras 74 et seq]

Article 14 of the Directive requires that doses be kept "as low as reasonably achievable". Any calculation of reasonableness must take account of the invalid concept of radiation dose and the poor state of knowledge on health effects and mechanisms of damage from man-made isotopes. The most important issue is "How much will conditional exemption make an irreversible contribution to environmental levels of radioactivity?". In this respect the principle of conditional exemption differs from the concept of Clearance only in degree. Until the outstanding questions about the extent of radiation detriment have been answered Conditional exemption orders must include restrictive conditions on the final disposal route for wastes. Incineration of contaminated waste must cease. Incineration of medical wastes in particular must receive urgent attention Uncertainties about low dose effects make it quite possible that hospitals are in fact cancer recycling centres.


13) Very Low Level Waste [para 91]

Landfill is another route for increasing general levels of radioactivity. LLRC has received assurances that dilution to achieve VLLW levels will not be allowed. This must be explicitly incorporated in law.


14) Justification Optimisation and dose limitation [paras 92 et seq.]

The arguments we have made in respect of ALARA (para. 12 on Conditional exemption orders) apply. Article 6.2 of the Directive requires justification of practices to be reviewed whenever new and important evidence about their consequences is acquired. We contend that this "acquisition" has happened, or at least should be viewed as ongoing.

The cost effectiveness analyses of all practices are due for revision.


Our growing Compendium of evidence was included as part of our response to the DETR.


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