Dr. Walter Claus -2= 19 April 1952 So far as future work is concerned I should like to emphasize a few points which I think need more attention than they have received heretofore. Certainly every effort should be made to obtain a complete map of the fall-out. Unfortunately such a map is not only very difficult to make in this inaccessible country but cannot be made by survey parties whose primary concern is public safety. It is also important that we continue to investigate the combined problems of particle-size and specific activity. have been few and ambiguous. To my knowledge results so far Dr. Bergen Suydam at Los Alamos has recently begun an independent study of fall-out in connection with the use of the Eniwetok Proving Ground. He may be able to offer some further suggestions to assist you in planning your work. Very truly yours, hk beg Le. FELT a J-Division GLF: lh Distribution: 2-W. Clausq—~g7 1 ~ We Ogle L-=- G, Felt 1 = LASL MAR 1 -= J-Sequ J-Sequence ence US DOE ARCHIVES 326 U.S. ATOMIC ENERGY COMMISSION RG 00 WS FORIAN Collecis. — //32 Box Folder 3362 #*/o (D8M)