12. 



NBS Handbook 58 (4). This was published at a time when relatively 

 little detailed information was available outside of the classified litera- 

 ture (and probably little within it) concerning the behavior of quantities 

 of activity above "tracer levels", when contained in systems comparable 

 to natural aquatic environments. The definition of high level waste has 

 changed since publication of the handbook. Hundreds of curies were 

 then considered high level, whereas present day operations are at the 

 hundreds of megacurie level, and reasonable estinnates of quantities 

 to be expected in the near future are in the megamega curie range. 

 The situation has changed so drastically since the publication of Hand- 

 book 58 that the quantities of activity then considered to be high level 

 are now in the low end of the low level range. 



At the time Handbook 58 was being prepared the marine environ- 

 ment was not as well understood as it now is. Studies of large scale 

 eddy diffusion processes, and the development of theories to generalize 

 the results, were not well enough advanced to permit an evaluation of 

 the dispersal and dilution of material from a disposal site. Also, very 

 little was known concerning the extent to which marine organisms can 

 concentrate dissolved and suspended substances from their environment. 

 It is not surprising, therefore, that Handbook 58 is primarily an 

 enumeration of the factors thought at that tinne to be pertinent to the 

 containment and dispersal capacity of the oceans. A review of the 



