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INTRODUCTION 



This paper examines in a preliminary way the institutional issues 

 associated with the potential sub-seabed disposal (SSD) of radioactive 

 wastes. This technique, as currently conceived, involves the burial of 

 such wastes in sediments of the seabed in abyssal plains located away from 

 the edges of tectonic plates and away from the rims of the ocean basins 

 (mid-plate/gyre regions, or "MPG") . Due to the technical complexity of 

 this method of disposal, it will likely only be employed for certain com- 

 ponents of the nuclear fuel cycle waste stream. These include high-level 

 wastes (HLW) left after reprocessing of- spent nuclear fuel spent fuel 

 itself in the event that it is decided to dispose of all or some of it 

 directly without reprocessing, and wastes containing transuranic elements 



(TRU wastes) which are generated during the operation of power reactors, 



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military weapons, manufacturing operations, and reprocessing. The 



intent of sub-seabed disposal for these types of wastes would be to 

 assure virtually complete isolation of the wastes for the time necessary 

 to bring them down to acceptable levels of radioactivity before significant 

 quantities were released into the environment — variously estimated at 

 100,000 to 3,000,000 years. Emplacement techniques could also be used for 

 low-level wastes (LLW) which do not fall into any of the above categories; 

 at present, however, such wastes are regularly disposed of by shallow burial 

 on land or (by several countries other than the United States) through dump- 

 ing of containers of LLW at sea. 



While the international decisions concerning sub-seabed disposal itself 

 and the arrangements for other aspects of the nuclear fuel cycle which might 



