693 



However, it is evident that there are other factors involved 

 in the revised definition besides a wish for scientific rationality. 

 The exparisicn of civil nuclear pov/er crogramnnes is seriously 

 threatened by the inability of its proponents to demonstrate 

 a safe disposal option for the steadily accuinulating highly active 

 wastes. The highest levels of waste- the liquids arising from 

 reprocessing, are heat producing and cannot be stored in a fail- 

 safe condition: they are vulnerable to disruption of services. 

 However, they occupy a small volume, and are stored within establish- 

 ed sites. The larger volume of non-heat producing highly active 

 wastes (termed 'intermediate'), however, present some embarassnent 

 because they will soon require a special storage site and thus 

 become a focus for public awareness of the 'unsolved' waste problem . 

 In Britain, in particular, there has been intense opposition, 

 often from county councils, to even a research programme of rock 

 drilling for a land-based disposal site. The U.K. government 

 recently abandoned its drilling research programme and is leaning 

 toward 'interim' storage above ground. Its advisory committees 

 are recommencing a slow but steady increase in its ocean disposal 

 programme. As recorded in the ?SRG critical review, the currently 

 expanded dumping rate, if maintained for several decades will 

 allow the U.K. to dispose of some of its more intractable alpha 

 contaminated wastes. There remain, however, large accumulations 

 of high-active waste (which the U.K. is anxious "o categorise 

 as 'intermediate') from the nuclear power programme, consisting 

 of decommissioned or worn-out reactor components, sludges and 

 resins, filters etc. from treatment plants, and the cladding 

 from reprocessed spent fuel. 



If the ' de minimus' criteria were adopted, nuclear states, 

 (especially the U.K.) would be able to present the ocean as a 

 relatively cheap and simple 'solution' to the high active- waste 

 problem. Their success would depend upon producing convincing 

 models of the impact to human health and to marine biota, and 

 with this in mind, a large research effort is under way. The 

 early results of assessment have all maintained that current 

 and immediately planned activities will have a negligible impact. 



Assumptions of research programme into environmental impact 



Given the apparent rationality of the de minimus approach, 

 it can be seen that the research programm.es into environmental 

 effects become a crucial element in the acceptability of the 

 criteria. The preliminary results of these programmes and the 

 assumptions upon which they are based have been critically reviewed 

 elsewhere. It is evident that some assumptions are not scientifically 

 tenable, indeed, many of the acknowledged experts party to the 

 IAEA research effort admit the inadequacies of the current models. 

 Controversy exists over the paucity of oceanographic data (on 

 upwelling, biological activity on the ocean bed, bottom.-currants 

 etc), and it is evident that zhe deep ocean floor is a more complex 

 ecosystem than assumed in the early radiological -odels. 



