How many dead people?
According to officially accepted risk estimates, 10microSv per practice, multiplied by 10 overlapping practices represents 50,000000 x 100 x 10-6 x 0.05 = 250 fatal cancers per year of the practices. It has not been shown that this complies with the ICRP principle of Justification of practices, and the ethics of exposing the public to this risk are to say the least dubious, even if detriment had been accurately estimated, but it has not. It is based on a large number of assumptions. Many of them are extremely crude and some of the most crucial are demonstrably false.

As we show in this response, there is no international consensus on the scale of health detriment from nuclear pollution, although the ICRP and its satellites such as National Radiological Protection Board claim there is.

The conventional model of radiation dose is scientifically unsafe. Given the many criticisms that have been made of it on theoretical grounds, and given the amount of epidemiological evidence suggesting that it is in error, any reasonable person would conclude that pending resolution of the scientific disagreements avoidable releases of radioactivity ought not to be permitted. Clearance and the subsequent recycling, reuse, and disposal of contaminated materials does not comply with the ALARA principle. The issue of relevance to this consultation therefore switches from
"Do the Clearance and Exemption provisions comply with the Directive's dose criteria?" to
"How much radioactivity will be released from nuclear sites where only workers are exposed; how much will accumulate in the environment where everybody is exposed?"

Conclusion
The central flaw in the proposed Clearance provisions is the absence of limits to the quantity of radioactivity that might be deregulated

As far as concentration levels are concerned, the proposal to allow contaminated materials to be released from regulatory control at any level ensures the widest possible distribution of the radioactive content and the contamination of the largest possible number of people, many of whom will not be born for many years, and none of whom can be assumed to derive any social or economic benefit. Such practices are contrary to the International Commission on Radiological Protection's universally acknowledged principles.

RECOMMENDATION
Wastes should be compacted on site and stored in isolation from the environment, at least until adequate research into the biological effects of specific isotopes has been reported. This complies with ICRP's principles, since
a. doses will be incurred almost exclusively by workers who derive clear benefits from their employment
b. doses will be monitored, and
c. doses will be due mostly to external radiation, whose risks are moderately well described.

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Part 2 of this paper shows the flaw in using EVs to derive CLs.

Part 3 outlines the assumptions behind the Directive's radiation hazard models and shows that there is a debate about their scientific validity and reliability. This debate is being conducted between scientists at the highest level of competence.

Part 4 answers specific points in the Consultation document.

Appendix 1 is a compendium indicating that there is a large amount of epidemiological evidence that health detriment associated with low level radioactive contamination is greater than predicted by the currently accepted model, plus experimental evidence and theoretical considerations. The compendium makes no pretence of being exhaustive and it includes references which are themselves compendiums of similar evidence.

Latest developments not included in the compendium are:
* Nuclear workers monitored [Carpenter 1998] for internal contamination have a higher risk of cancer.
* Leukaemia in the children of male nuclear industry workers [Draper and Little 1997] is nearly double (1.83 times) the national average.
* A major new analysis of radiation workers [Muirhead 1999] reanalysed by Busby [Busby 1999] shows that they have a cancer mortality rate 6 times greater than expected on the basis of official risk factors for external radiation (internal doses are not known).
* A very new study [Roman 1999] of cancer in the children of nuclear workers shows a risk 4.4 times the national average when analysed by a more appropriate statistical method than used by the authors. Statistical strength is very high. A full criticism will be published in Radioactive Times vol. 3 #2 and at www.llrc.org/roman.htm. (and see correspondence in New Scientist 29.5.99 and 12.6.99).

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Part 2

Evs and CLs: A basic principle ignored.
The values laid out as thresholds for Exemption from reporting and authorisation were calculated on the assumption that Exemption was intended only for undertakings using small quantities of radioactivity. 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 conditions]. DETR states [Consultation Paper para 22] that

"the figures .. in Annex 1 were derived mainly on the basis of limiting exposure of workers ... and they are not therefore directly applicable to RSA 93 which is concerned with waste and the public."

This is wrong. Radiation Protection 65 gives extensive analysis of public exposures, mainly from landfill disposal. It is clear from the calculations that the amounts of radioactivity assumed for disposal from Exempt undertakings were small enough for the authors to feel they could ignore Collective Dose. [RP 65 para 3.2]. The amounts of radioactivity in materials which may be considered for Clearance are many orders of magnitude greater than could possibly be released from Exempt undertakings, and Collective Dose considerations would dominate, yet the proposed Clearance Levels are generally only one order lower than the Exemption Values.

Release of metal after licensed smelting

Possibly the most culpable shortcoming of the DETR consultation is its silence on the question of Clearance of metals melted under license, although EC Guidance implies that such a practice would be available to be approved by the authorities. Since it creates a massive loophole with the potential of allowing very high proportions of the radioactive inventory to achieve deregulation this issue must be deplored in the strongest terms.

Considerable amounts of metal melted before Clearance already exist. BNFL proudly boasts that in decommissioning the Capenhurst Gaseous Diffusion plant they have rendered 97.3% of the gross materials fit for free release. Some thousands of tonnes of aluminium from it have been sold, while more await sale. Radiation Protection 89 says [para 3.1.vi] that Clearance should not be available for metal melted before Clearance. The logic is that:

"The radiological assessments used to derive the clearance criteria for scrap metal assume that only a fraction of the scrap in the furnace comes from cleared scrap. Ingots produced in a licensed smelting facility are made from 100% radioactive scrap. Therefore the clearance levels for scrap are not appropriate for metal released after being melted in an authorised facility." [from RP 89 para 7.3]

But the same paragraph also sets out an escape clause:

... "Nevertheless there are a number of advantages to clearance after melting, such as decontamination effects from nuclide separation and simplification of the monitoring procedures, so that the competent authorities can authorise this practice after an appropriate investigation of the radiological consequences."

It may be valid to use such metal within the nuclear industry, but this type of procedure must be viewed with great caution.
First, even if the metal itself is reused within the industry the supposed "decontamination effects from nuclide separation" are likely to include concentration of some nuclides in slag and dust, which have a variety of uses and disposal routes outside the nuclear industry.
Secondly, the logic of allowing the Clearance only of unmelted scrap is to ensure dilution by melting after Clearance [RP89 para. 2.3]. Bearing in mind that the radiological criteria underlying the Directive state quite clearly that dilution in the environment is seen as a way of reducing doses and that they ignore the cumulative impact of the gross quantities of radiation released, there is every reason to believe that the authorities will view metal melted under licence as suitable for Clearance provided only that subsequent dilution can be assured. This clearly represents a route by which large proportions of the waste inventory could be Cleared, increasing Collective Dose to the population at large while only the industry enjoys any benefit.

We recommend that none of the products of licensed smelting should ever be released from regulatory control, unless radioactive decay has reduced their activity significantly.

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Part 3 Assumptions behind 10microSv benchmark

Within the 10microSv benchmark modelling based on the physical characteristics of specific isotopes has been used to develop the Directive's Exemption Values and hence the Clearance Levels. This process has ignored the importance of biological mechanisms of radiation induced mutation which are poorly understood. Much research needs to be done on the biological behaviour of specific isotopes before there is any regulatory change which would lead to increased quantities of them being released into the environment. All the equations used in determining the 10microSv value assume models which themselves depend on questionable assumptions:

a. that there is a linear relationship between dose and health effect.
Much of the available data show a supralinear dose response curve (higher effects per unit dose in the very low dose range) or a biphasic curve (higher effects per unit dose in the very low dose range with reduced effect per unit dose at slightly higher dose, followed by an increase as dose increases toward the high dose range.)

b. that the intensity of radiation dose can be understood in terms of an "average energy transfer" model of absorbed dose
there is a long-standing debate about the validity of applying the absorbed dose concept to radiation protection in the low dose range. The conventional model underpinning the Directive's Clearance criteria views "Absorbed dose" as energy transfer affecting large volumes of tissue. This flies in the face of the observation that radiation causes genetic damage by discrete tracks each of which impinges only on the cells within the range of the charged particle and only on the cells which lie in line with the direction of the particle (The recent discovery of an as yet poorly understood "bystander effect" does not invalidate this statement - it merely supports the contention that knowledge of the mechanisms of radiation- induced genetic mutation is very inadequate). On the microscopic level (i.e. at the level of the cell) radiation "dose" or "energy transferred" is very high for those cells which are hit, and zero for those which are missed. The conventional approach of averaging the energy transfer from radioactive decay events across a whole organ or the entire body can be likened to emptying a Colt 45 into a football stadium and averaging the effect of the 6 bullets across all the 25,000 spectators. The assumption that between them 25,000 people should be able to stop six bullets without any of them feeling more than a tap on the arm will not console the six grieving families.
It is more appropriate to quantify "dose" in terms of the number of tracks received by exposed cells per year, compared with the Natural Background Radiation yardstick of one track per cell per year. Qualitative factors should be incorporated to take account of differing decay energies from different isotopes.

c. that there is an equality of effect between acute gamma and x-ray doses delivered externally and chronic radiation from incorporated isotopes including alpha and beta emitters
This is a large assumption. It is not even valid to assume equality of effect between acute external g and fractionated x-rays (NRPB 1999). The pivotal status given to the studies of Hiroshima survivors, which are studies only of external gamma radiation and are incapable of giving any information at all about the effects of incorporated fission product isotopes, is a serious flaw in radiation protection.

d. that the biological behaviour and health effects of man-made isotopes are not qualitatively different from natural background radiation and naturally occurring isotopes.
Another large assumption, made possible only by the essentially physical, energy based model of radiobiology, and undermined by the epidemiological facts listed in Appendix 1.

e. that the population is uniformly radiation sensitive. This is not sustainable. The Hiroshima and Nagasaki studies did not begin until 1950 and data exclude people who died in the first few years after the bomb.
These studies are really based on a 'radiation resistant' population. Alice Stewart (STOA 1998) has also shown that even among the Japanese survivors who are included in the study children and those over 55 years of age carry an exceptionally high cancer risk. This finding renders all the more unacceptable the assumption made by DETR's consultants WS Atkins and Electrowatt (DETR/RAS/98.004 p 8) that they should calculate Clearance Levels on the basis of doses to adults "because most of the population of the UK are of adult age." Some of the Clearance scenarios would put children at far higher risk of ingesting radioisotopes. Notable in this respect are scenarios leading to inclusion of transuranic isotopes in smelter slag and thence into garden fertilisers and playground surfaces, and clearance of contaminated soil. What kind of society is it that ignores the greater susceptibility of its children and then puts them at disproportionately higher risk of incurring those doses?

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