41. 



by rough timbers into which selected end products are discharged 

 /products with only a low level of radioactivity/. The water table 

 is 250 or more feet below land surface, and over most of the Hanford 

 area the unsaturated interval is occupied mainly by glacial outwash 

 -- silt, sand, and some gravel. A few areas adjacent to old cribs 

 (where discharge of wastes has been terminated) have been tested by 

 sinking holes at intervals around them, sampling the earth material, 

 and analyzing it. This has delineated, beneath the cribs, roughly 

 pear-shaped zones in which fission products have been adsorbed by 

 the earth materials. I know of no case where the total quantity of 

 fission products fixed in the pear-shaped zone can be shown to be a 

 major part of the products that were in the total volume of fluid dis- 

 charged into the overlying crib. 



MR. M. HAWKINS: Where did the rest of it go? 



DR. D. GRIGGS: Is that statement based on the water removed 

 in the survey? You didn't find fission products in solution-- is that 

 what you meant? 



MR. PIPER: The earth material was not saturated when test- 

 drilled. It was not dry in the sense that it contained no water. Ex- 

 cept for a thin zone near the land surface, probably all this material 

 naturally contains that amount of water which it can retain against the 

 force of gravity, and essentially all the fluid added to the cribs must 

 go on down and ultimately reach the water table. We can conclude 

 that all the fission products put into a crib either are trapped in the 

 underlying area or have gone down somewhere. 



Before some of the later cribs were put into use, observation 

 wells were drilled adjacent to them and some holes were angled be- 

 neath the axis of the crib. 



DR. J. GILLULY: What sort of a drill did you use? 



MR. PIPER: Cable tool. The mast was canted, a guide casing 

 was set, and the hole was drilled carefully and with fair success in 

 getting under the axis. 



DR. T . P. KOHMAN: What kind of material? 



MR. PIPER: Glacial outwash largely. Over most of the area 

 no basalt highs were cut above the water table. 



