Re: Yucca Mountain

[don@radpro.uchicago.edu]

There is an article on Yucca Mt. in the July 1996 Scientific American (Or 
possibly June 96)  The issue you raise is discussed in some detail. Some,
including the Nat. Acad. of Sciences seem to be suggesting that 10,000
years may be too short.  Much longer time scales - such as 1,000,000
years - should be considered to account for the transuranics in the waste. 
On time scales that long all waste containement is assumed to have failed 
and any remaining nuclides are now migrating through the rock ( at a rate 
which depends on predictions of the weather 1,000,000 years from now as well 
as the geology of the site). The nuclide of "concern" at this time scale is 
Np-237.  Rebutting this "concern" is the evident fact that natural uranium 
deposits still exist and, if left in that state, appear to pose little 
threat to wipe out life.  On the other hand, we don't know how many nat. 
Uranium deposits have already washed away.  

___________________________________________________________________

Don Jordan                          Tel. (312) 702-6299
Office of Radiation Safety          Fax        702-4008
The University of Chicago           email: don@radpro.uchicago.edu
1101 East 57th Street, Room 11
Chicago, Illinois  60637  
                -- Any opinions are the author's --