b) The third entry in the column projects 4422 extra cancer deaths during the course of 30 years. I would like to know how that calculation was made. c) The fourth entry projects a usual rate of 140 birth defects (congenital), presumably in a total of 1400 live births over 30 years. Is that based on Marshall Island experience? Applying BEIR factors (?), radiation exposure would increase this total by 12. What factor was used? All of this, I believe, is rather simple and direct;and. the information will help us a great deal. If my questions are not clear enough, perhaps you might find it convenient to telephone me. Obviously the calculation of risk lies at the very heart of the decision-making We shall very much appreciate your help. Sincerely yours,