SPORET| UNIVERSITY OF CALIFORNIA Los slamos Scientific Laboratory (Contract W-7405-ing-36) P.O. Box 1663 Los 4lamos, New Mexico In Reply Refer To: DIR-638 7 July 1951 Dr. Shields Warren Director, Division of Biology and Medicine U, S. Atomic Energy Commission 1901 Constitution Avenue, NW Washington 25, D, ©, Dear Dr, Warren: 4s I indicated to you in my letter of June 22, 1951, I would keep you informed of any results obtained at Los Alamos bearing on the safety of Operation JANGLZ. There is herewith enclosed an informal report by Dr. Gaelen Felt dealing with this problem and making some recommendations which are rather startlingly different from those which were being suggested carlier, Although I am not yet prepared to make any formel statement from the Los “lamos Scientific Laboratory on this matter (nor is it clear that I am supposed to do so), nevertheless I believe that you would be interested in Dr. Felt's approach. We are endeavoring tos tudy the small particle problem further, although this scems to present extreme difficulties. However, 1 am currently of the opinion that the major problem in safety is going to lie in this fieldrather than in any danger from external radiation dosage. We will, of course, continue to keep you informed of any progress we may make, Yours truly, NEB/hgc /s/ N. E. Bradbury Director LA, 2A - Dr. Shields Warren w/encl. 3A ~ C, L. Tyler w/encl. aA ~ 4. C. Graves wo/encl. 5A ~ br, T, L, Shipman wo/encl. 6A 7A ~ Reading File ~ File "DowAREHIVES* i }