29. 



that is, there is no containment. In the second, the waste leaches from 

 the container at a rate determined by various properties of the container. 



In the first case, a specific example is cited in which 0.01 curie 

 IS contained in 50 gallons, the concentration then being 5.4 x 10" 

 uc/ml. Ten hours after introduction, the peak concentration, in the ab- 

 sence of a mean current to aid in dispersal, will be approximately 

 6 x 10" uc/ml. The relationship that has been developed is such that 

 the maximum concentration can be calculated as a function either of 

 time after introduction, or of distance from the disposal site. For the 

 latter case, the peak concentrations at 10, 100 and 1000 meters from 



the 50 gallon - 0.01 curie uncontained source will be 1.5 x 10" , 3 x 



-9 -11 



10 , and 4 x 10" uc/ml respectively. Again, these are conservative 



figures, for essentially the same reasons as noted above. They suggest 

 that although initially the contamination at the location of the disposal 

 container may be high, it dies away rapidly in space and time. 



The second case, that of controlled leaching, more nearly describes 

 the situation that would exist for the disposal of wastes in metal con- 

 tainers, in which the wastes were mixed with the concrete at the time of 

 packaging. The analysis of this situation is in some ways similar to the 

 "gross source" noted above. The controlled leaching situation presents 

 a semi-continuous source for diffusion and although the initial peak con- 

 centration will be lower than in the case of free diffusion, the concen- 



