Foreign Relations of the United States, 1958–1960, Volume III, National Security Policy; Arms Control and Disarmament, Microfiche Supplement

519. Tabs A and B to Memorandum of Conversation Among Principals of Geneva Test Group¹

Washington, January 19, 1960

Tab A

Washington, January 19, 1960, 5 p.m.

AGENDA

Meeting of Principals of Disarmament Working Group

Tuesday, January 19, 1960 5:00 PM Room 5104 New State

1. Should the US advance a proposal based on a signal strength threshold in the Geneva nuclear test negotiations? If so,

2. What should be the level of the threshold?

3. What should be the level or number of inspections?

4. Should a specific threshold level and a specific level of inspection be proposed at Geneva now?

Tab B

DRAFT INSTRUCTION

Within the general framework course of action stated by Dillon letter of January 6 to Foreign Secretary Lloyd USDel may after coordination with UK explore in general terms with USSR following approach based upon a signal strength threshold for underground tests. In presenting proposal USDel should from outset reaffirm and make clearly understood US position that it will agree to cessation of nuclear weapons test explosions only in environments where adequate safeguards can be applied. In discussion with UK USDel should draw as required on technical paper provided at the meeting of principals January 8. Unless SOVS show interest in agreement on basis principles outlined USDel should not enter into detailed technical discussion with USSR on methods of calculating magnitudes, kiloton equivalents of various magnitudes, exact criteria to be employed in locating events, or number of unidentified events at various levels which would result from application US criteria for identification except insofar as specified in para 6 below. If SOVS show such interest USDel should seek further instructions on presentation these technical considerations.

In presenting proposal USDel should point out that in absence technical basis for establishment and operation control system covering all underground nuclear explosions, US nevertheless desires consolidate in treaty existing areas of agreement on cessation of nuclear weapons test explosions in environments to which adequate and agreed controls can now be extended. Proposal should be advanced as constructive approach to impasse in which we find ourselves as result continuing wide areas technical disagreement reflected report Technical Working Group II. Proposal for threshold approach represents (a) evidence US willingness seek test cessation in areas that can be adequately monitored (b) way to bypass existing disagreements between US and Soviet scientists on criteria for identification of underground events by basing inspections on events located by system (c) way to achieve a workable agreement despite existing disagreement and limitations as to detection and identification capabilities in lower yield ranges and disagreements on equivalent kiloton yields of events of given seismic magnitudes (d) way to move by phased approach as rapidly as technically feasible toward more comprehensive ban through lowering [or eliminating]² threshold as methods of detection and identification were improved by research.

USDel should outline key elements of proposal as including following:

1. US proposes phased treaty including in its first phase ban on underground nuclear explosions above a lower limit or threshold defined in term of magnitudes of seismic events detected by control system.

2. Proposal would be carried out under arrangements whereby number of inspections would be directly related to number of events above agreed threshold. Thus within the limits of technical capabilities, selection of appropriate threshold would depend in part upon level of inspection acceptable to USSR.

3. Treaty should provide for lowering threshold as system capabilities are improved through utilization of improved techniques, instrumentation and criteria or higher level of inspection. Program of joint research, including nuclear detonations as required, to improve detection and identification capabilities of system and develop improved criteria should be instituted as rapidly as it can be agreed; it could be continued by control commission when it is established. If USSR does not agree to join us, US feels obligated to proceed unilaterally in development of improved detection systems making use of nuclear detonations as required.

4. US believes agreement on criteria proposed by its technical experts in TWG II for use in at least initial phase would help meet SCV concerns as to wide range of events against which agreed level of inspection could be applied, since it would narrow number of events eligible for inspection as far as technically feasible at present time. If these criteria employed, US would propose agreed level of inspection apply only to events remaining unidentified by control organization after application these criteria. If, however, agreement cannot now be reached on criteria for identification, US would propose as way around this difficulty that agreed level of inspection apply to all events located by system.

5. US proposes that level of inspection be expressed as percentage of events above agreed threshold magnitude that remain unidentified after control commission has applied criteria proposed by US scientists at TWG II. This would reduce number of events eligible for inspection to lowest figure consistent with existing scientific information. It is, moreover, a formula which will automatically reduce the number of inspections as improvements in techniques and criteria are developed. If agreement on criteria for identification is not yet possible, however, US proposes that pending such agreement the level of inspection be expressed as percentage of total events above agreed threshold magnitude which are located by the system. USDel should recall US has also made clear in past that whether level of inspection should be expressed as percentage quota or numerical quota is of secondary importance in comparison to basic requirement that level of inspection should bear appropriate relationship to scientific facts and detection capabilities. Accordingly US would also be willing, if USSR prefers, to express the level of inspection in numerical terms based on a calculation of an agreed percentage in relation to the latest scientific estimates of numbers of located events or unidentified events it has presented to the conference. Since this would tend to re-open existing scientific disagreement which might otherwise be avoided, however, we would propose not to enter into a complex technical negotiation upon this basis unless a broad understanding in principle on the proposed approach can be agreed.

6. As a specific example of the application of the proposed approach, the US should propose a threshold of magnitude 4.75. Above this threshold 20% of all events unidentified by US criteria or alternatively 10% of all events located by the system would be subject to inspection. Depending upon whether agreement on criteria can be reached, all located events or all unidentified events would be eligible for inspection. On the basis of our best estimates this basis for inspection would result in from 10 to 20 inspections per year in the Soviet Union.

7. In answer to questions which will arise concerning certain matters our position would be as follows: you should, in your private coordination with the UK representative ahead of presentation, point out these:

a. Relative to our accepting a moratorium on weapon testing below the threshold, the US will not accept such a moratorium and would be free to resume such testing when its national security so dictated.

b. Relative to high altitude testing we would plan on “an agreed suspension of nuclear weapons tests in the atmosphere up to the greatest height to which effective controls can under present circumstances be extended.” If ground stations only were agreed, no higher than 100,000 KM. If Argus and far earth satellite systems are installed, no more than 300,000 KM.

1. Source: Agenda of Working Group meeting and draft instruction on threshold to U.S. delegation to nuclear test talks. Memorandum of Conversation is Print Document 240. Confidential. 4 pp. NARA, RG 59, Secretary’s Memoranda of Conversation: Lot 64 D 199.
2. AEC recommends deletion. [Footnote and brackets are in the original.]