21. 



DR. M. KING HUBBERT: Mr. Chairman, I would like to refer 

 to the "graybook" of March 31, 1955. In view of the oceanographic 

 discussions, I would like to comment on one statement that struck 

 my attention: it was stated that if wastes were put in the deep water 

 that they would have to be monitored by periodic observations, but 

 that no major cable company would guarantee a cable two miles long 

 for more than one or two trips . 



That statement struck me as being odd, and I checked with the 

 Schlumberger Company, who regularly lower things on cables down 

 oil wells as much as four miles deep, and I asked them what the life 

 of a cable is, and they said they are good for about 200 round-trips. 



DR. RENN: I am glad you brought that up, Dr. Hubbert, be- 

 cause one of the points made by a small group of men was this: that 

 the situation as far as monitoring is concerned has improved greatly. 

 First of all, plastics have been developed which have low adsorption 

 characteristics for fission products. Methods of signalling that per- 

 mit a high degree of leakage have been developed, so that deep water 

 systems would not become vulnerable to small leaks of sea water. 

 Instrumentation is improving rapidly and the present emphasis is on 

 increasing the sensitivity of the equipment. The conditions for hand- 

 ling sampling gear at sea differ from those of oil well logging. The 

 weights are greater, and there are sudden strains due to ship and 

 boom heaving, with the newer signal systems, longer effective life of 

 cables is possible, however. 



CHAIRMAN HESS: Are there any other questions you would like 

 to bring up while Dr. Renn is still here? 



DR. TRUMAN P. KOHMAN: I would like to ask a little more 

 about getting material into the ocean fiom coastal installations. Were 

 you referring to underwater? 



DR. RENN: This point was discussed more in detail by Dr. 

 Ewing. He offered it purely as a possibility. The question under dis- 

 cussion at that time was how to get the waste across the continental 

 shelf and out into deep ocean. His suggestion was simply that there 

 must exist a number of strata which incline seaward, below the sur- 

 face of the continental shelf, and intercepting the continental slope. 

 The density of the introduced waste being higher than salt water, it 

 would force the stream ahead and would eventually seep out below the 

 edge of the shelf. 



