48. 



cesium and strontium will help reduce the problem. 



DR. HUBBERT: In these remarks I am thinking about putting 

 wastes down in a well which may be 10, 000 feet deep. It will be 

 structurally a basin in shape. The rocks at that depth are always 

 full of water. If we inject into a sandstone at this depth, all the in- 

 jected fluid will do is flow out radially from the well. It is quite im- 

 portant it does not block the pores of the sandstone. Now, in a dilute 

 form as. far as the hot constituents are concerned, many of them won't 

 accumulate to form concentrations. 



DR. CULLER: But if the soil through which it passes has the 

 capacity for an ion exchange it will solidify. You will have solids. 



DR. HUBBERT: At a depth of ten thousand feet, we do not have 

 soil; we have rocks, and it is rocks I am thinking about. There may 

 be rocks composed of montmorillonite clay. We don't inject into 

 those. But we may have sandstones that have a percentage of clays 

 which may have important ion exchange properties. We might pos- 

 sibly be injecting into a limestone. The most desirable rock would be 

 sandstone; the clays we would avoid. The rocks occur in layers. The 

 sandstone is probably bounded above and below by clay stone, and the 

 sandstone may be several hundred feet thick. If we inject into the 

 thick, clean sandstone, there will be comparatively little ion exchange. 

 So, a part of the chemistry would be to get the waste ready for that 

 kind of an injection. 



DR. A. R. DENISON: I should like to inquire if there has been 

 any plugging in these cribs. Have any of these cribs at Hanford been 

 abandoned? 



MR. PIPER: One or two of the earlier ones have been discon- 

 tinued because of probable sludge in the base of the crib that may have 

 been suspended in the fluid when it entered the crib. Escape of fluid 

 was considered hazardous and the cribs were abandoned for that 

 reason. I am not familiar with the operation of some of the later cribs, 



DR. DENISON: Is there a plugging effect in the cribs? 



MR. PIPER: There definitely was in one or two of the earlier 



ones , 



DR. DENISON: Of something not going into the present cribs? 



