40. 



no place within the Commission jurisdiction are high level wastes 

 being discharged to the ground. Relatively low level wastes are 

 going to cribs at Hanford. 



DR. KOHMAN: I wonder if someone would please define a 

 crib . 



DR. LIEBERMAN: We call them cribs or caverns. They are 

 simply excavations that might be 30-foot squares in plan, and as 

 much as 30 or 40 feet deep. They are filled with coarse broken rock. 



DR. KOHMAN: Is it lined? 



DR. LIEBERMAN: No. Previously there was a crib -like 

 structure of timbers to hold the excavation. The purpose of the 

 rock is to distribute the waste so as to take advantage of the full 

 cross-section of the column when the waste is pumped in. The top 

 of the pit is covered with some impervious membrane which is in 

 turn covered with the natural soil; the piping into the pit may be cov- 

 ered so it is safe to walk over, and the membrane sheds what little 

 precipitation there is in the area. 



It is a very rough structure, but it is surprising how expensive 

 it is to build a lot of these cribs. It costs from a tenth of a cent to 

 one cent per gallon to discharge the relatively low level wastes into 

 the ground at Hanford. 



DR. GILLULY: The statement has been made several times 

 that this is soil. It is difficult to persuade me that there are 3 50 or 

 400 feet of soil at Hanford: there is an abundance of Columbia River 

 lava, there are gravels, and there are jointed rocks, all of which 

 provide channels to carry the solution through or diffuse it. . I would 

 like to have Dr. Piper explain the hydrology. 



Mr. A. M. Piper, Staff Scientist, Pacific Northwest 

 U.S. Geological Survey 

 Box 3418 

 Portland 8, Ore. 



CHAIRMAN HESS: I was going to call on you later, Mr. Piper. 

 Would you like to present your views now? 



MR. PIPER: A crib is merely a shallow excavation supported 



