16. Mr. Martin, as Acting Secretary of State for External Affairs, reported that the United States was going to test a large nuclear weapon in an underwater explosion somewhere off the western coast of this continent. Canada had not been advised where this would take place nor the direction or distance of the testing area from Canada. The U.S. authorities had been approached and had given an assurance that there would be no danger to Canadian ships, aircraft, or fishermen from the explosion or from the fall-out. The U.S. would have no objection to our making this assurance public.

17. In the course of discussion the following points emerged:

(a) Canada had been informed earlier of this year's testing programme, but this underwater explosion had not been mentioned until a few days previously. While the U.S. had said it would take all possible precautions to avoid damage, this did not mean that the effects of the test might not be unfortunate. Neither the U.S. nor Canada knew what effect the explosion might have on the salmon fishery, for instance. Mistakes in judgment had been made before and some of the results of previous tests had been unexpected.

(b) If Canada could persuade the U.S. to drop this test it might be worth doing. However, this did not appear to be possible and no formal protest had been made. In answer to any questions which might arise following the test, it could be stated that Canada had expressed concern.

(c) There was much public concern that the results of these atomic tests were not worth the dangers which might arise from them. Consideration might be given to making representations to the President. No such step had been considered but some officials had expressed their worries to U.S. officials on the effects of the tests made in the past. Canadian health authorities believed that there had been no serious effects so far from radioactivity but they could not be sure of this. Certain eminent authorities in the U.K. held a different view.

18. The Cabinet noted the report of the Acting Secretary of State for External Affairs on the forthcoming underwater test of a nuclear device to take place off the western coast of North America. ...