Present:
The Prime Minister (Mr. Diefenbaker) in the Chair,
The Secretary of State for External Affairs (Mr. Green),
The Minister of Finance (Mr. Fleming),
The Minister of Veterans Affairs (Mr. Brooks),
The Minister of Transport (Mr. Hees),
The Solicitor General and Acting Secretary of State (Mr. Balcer),
The Minister of National Defence (Mr. Pearkes),
The Minister of National Revenue (Mr. Nowlan),
The Minister of Agriculture (Mr. Harkness),
The Minister of Fisheries (Mr. MacLean),
The Minister of Labour (Mr. Starr),
The Postmaster General (Mr. William Hamilton),
The Minister without Portfolio (Mr. Browne),
The Minister of Mines and Technical Surveys (Mr. Comtois),
The Minister of National Health and Welfare (Mr. Monteith),
The Minister of Defence Production (Mr. O’Hurley),
The Minister of Public Works (Mr. Walker),
The Associate Minister of National Defence (Mr. Sévigny).
The Assistant Secretaries to the Cabinet (Mr. Fournier), (Dr. Hodgson).

RESEARCH ON DETECTION OF NUCLEAR EXPLOSIONS; CANADIAN PARTICIPATION

1. The Prime Minister said that the U.K. Prime Minister had asked whether Canada would agree to participate in a proposed international programme of research on the detection of nuclear explosions. The U.K. would raise this subject at the Summit Conference, and therefore Canada's reply would have to be made on May 16th.

It was hoped that the U.S.S.R. would agree to a treaty providing for the end of nuclear testing in the air, on water and on the ground, and a moratorium on other explosions, particularly underground explosions. This would constitute a major step toward the end of all testing, and this appeared to be the only positive outcome that could reasonably be anticipated from the Summit Conference.

The contemplated treaty would in its initial stage be limited to all explosions of more than a seismic magnitude of 4.75, because studies had shown that the proposed control system would not be capable of detecting all explosions below that "threshold," particularly explosions underground. The negotiating countries had therefore agreed in principle to work for a limited treaty in the near future and at the same time to undertake a research programme to ascertain the weaknesses of the control system and how they might be corrected.

Under the proposed three-power treaty the United States would explode nuclear devices in the southern part of its territory and would study the seismic effects. The U.S.S.R. would conduct a similar programme. The U.K. share of the proposed co-ordinated programme would be to study the U.S. explosions from outside U.S. territory.

The U.K. had asked Canada to permit the establishment on Canadian territory of (a) a central control post, developed from an existing station in Canada, which would serve as a prototype for the control posts in the proposed international system, and (b) about 20 mobile bases consisting of trucks carrying seismological instruments. The overall cost of this programme over a period of three years was estimated at $7 million. There would be 16 scientists at the central post and about 70 scientists distributed among the mobile bases. The U.K. scientists could make their most effective contribution to the programme at stations in Canada, because any attempt to monitor U.S. explosions in the U.K. would be handicapped by distance and by seismic noise from the continent of Europe. Because it adjoined the U.S. and because of its geological structure, Canada was a much more suitable place for the conducting of such research. Dr. P.L. Willmore, a Canadian seismologist, might be selected to take overall charge of the U.K. programme, directing it from the U.K.

The plan would not involve nuclear explosions in Canada, and the cost would not necessarily be borne by Canada alone. The central control station had to be placed on granite rock at a distance of 500 miles from any large body of water. The U.S. explosions would occur on an east-west line in the latitude of North Carolina, and the mobile stations in Canada would be located about 200 to 300 miles apart, in an east-west line. Each station would have a mixed team including scientists from each of the three great powers plus neutrals.

The Soviets had given an informal indication that a programme of this kind would be acceptable to their scientists. Under the proposed nuclear tests treaty there would be agreement covering on-site inspection of each of the three powers by the others. The Russians were thinking in terms of 6 inspection visits each year, and the Americans were hoping for 100 each year, while the U.K. representatives were hoping for a compromise between these figures.

The Prime Minister said he had received a note dated April 28th from the U.K. Prime Minister asking for Canada's consent in principle and indicating that such a project would have useful possibilities for a wider degree of Commonwealth support and co-operation. For example, Australia and New Zealand might be willing to send some of their scientists to man the detection stations. Mr. Macmillan had sent further notes to Mr. Diefenbaker on May 10th and 11th asking for a reply early in the following week.

If a nuclear tests treaty could be brought into effect between the three powers, other nations and particularly China would subsequently be invited to join in binding themselves to its terms. France was not prepared to participate at this time.

An explanatory memorandum was circulated, (Memorandum, Secretary of State for External Affairs, May 14 — Cab. Doc. 158-60).†

2. During the brief discussion the following points were raised:

(a) Some said the Canadian government had consistently urged that nuclear explosions be stopped, and that the proposed programme would imply Canadian assent to such explosions. Canada should not abandon its declared policy, at least before a three-power agreement was reached. If there was agreement at the Summit and if, subsequently, Canada was asked to participate, there would be less reason for concern. The U.K. had not consulted Canada until just before the Commonwealth Prime Ministers' Conference, and then had expected an almost immediate reply.

(b) Others said that the tests contemplated in the research programme should not be opposed, because they were directed toward the end of finding a practical means of abolishing all nuclear explosions. The nations would not agree to a ban on nuclear explosions unless they were satisfied that such explosions could be detected. An agreement at the Summit for a limited programme on this subject would constitute a worthwhile achievement.

3. The Cabinet noted the statement of the Prime Minister on the inquiry received from the United Kingdom on whether Canada would participate in a proposed international programme of co-ordinated research on the detection of nuclear explosions, and agreed to consider the subject further at the next meeting of the Cabinet.
. . .