TNAG-0836-FCO40-1044-Comprehensive-Test-Ban-Treaty-national-seismic-stations-on-U-1979 — Page 59

CONFIDENTIAL

DSR TIC

in Scotland, none of those named by the Soviet Union would for varying reasons be easy to accept, we could probably find 9 others which would be harmless, although unnecessary on technical grounds. Indeed some of the sites would have such a high level of seismic background noise that they could only monitor testing not detectable by Soviet NTM if the source was within a few tens of kilometres. Such a list may nevertheless be negotiable, since the Russians have indicated that they are willing to consider different sites and that technical justification is secondary to their political requirements for "equal obligations". But we should bear in mind that the sites

selected by the US for NSS in the Soviet Union have been carefully chosen on technical grounds, and we should not give the Russians a pretext for suggesting technically useless locations on their territory. There would also be a risk that the NSS in British dependent territories would be widely seen to have no technical basis. But we believe that we could ! explain frankly that they were (as the

Russians have themselves said privately) the

political price of satisfactory NSS in the

Soviet Union. A further potential

difficulty, which it would not be in our

interests to raise now with the Russians, is

that our implied acceptance of "equal

obligations" at this stage would have

implications for our position if the treaty was extended after 3 years and the Americans sought an upgraded NSS system in the Soviet

Union. However this course would have

important advantages. Since the Soviet Union has agreed to accept 10 NSS if we offer 10, we could move quickly to the negotiation of the important outstanding aspects of NSS, such as their quality and time of installation. The Americans seem strongly to favour our accepting 10 NSS and we might well find them impatient if we went for some other option. Most

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