§ 40. Mr. Frank Allaunasked the Secretary of State for Foreign Affairs if, in view of the facts that 10 of the 51 recent underground nuclear test explosions in the United States of America have caused radioactive clouds in the atmosphere and limited leaks of radioactive material, he will take the initiative in reopening talks to end all such tests.
§ Mr. R. A. ButlerWe shall make every effort at the Geneva Conference to secure a comprehensive ban on all nuclear tests. But before we can do so we shall need to reach agreement with the Soviet Union on the problem of verification of underground events. As the nuclear tests referred to by the hon. Gentleman took place in the United States, I have asked the United States Government to let me know the facts. Their reply is rather long. I shall therefore, with permission, circulate it in the OFFICIAL REPORT.
§ Mr. AllaunWhile I thank the Foreign Secretary for that reply, may I ask him, first, whether he will tell the House if there is any danger of failure to prevent radioactive leaks in America affecting other countries and thus breaching the agreement? Secondly, in view of this, and since it is six months since that Treaty, what specific proposals are the British Government putting forward at Geneva?
§ Mr. ButlerIn reply to the first part of the hon. Gentleman's supplementary question, if he will read the American reply, which is fairly long—it will be in the OFFICIAL REPORT, which I thought was the best way of handling it—I think he will find the answer to his question. With regard to the second part of the supplementary question, we are taking every opportunity at Geneva to press for a broader and more comprehensive ban on all nuclear tests.
§ Following is the information:
§ United States Memorandum on Nuclear Tests
§ The wording of the Parliamentary Question, perhaps owing to inaccurate Press reports, implies that the series of 51 explosions mentioned in the article in Science took place very recently. In fact, the article itself states that they took place from 15th September, 1961, to 24th August, 1962. 32 These and other tests discussed by Dr. Martell all took place prior to the signature of the partial Test Ban Treaty, and no question of violation of that Treaty is raised by his article.
§ The purpose of the article appears to be to prove that underground tests have been the principle source of radio-iodine fallout in the United States. Dr. Martell bases this conclusion largely on the claim that on two occasions when fallout of radioactive iodine was detected in the United States, the source of this radio-activity was at least in part from United States underground tests, rather than atmospheric tests. Reputable United States scientists disagree with this contention and are quite certain that the radioactive iodine fallout in these two cases came from atmospheric tests, in one case from a Soviet test and in the other from a United States test. Dr. Martell's statement that 10 of 51 announced tests from 15th September, 1961, to 24th August, 1962, produced radioactive clouds is both incorrect and misleading. The fact is that only five events during this time period released radioactivity that was detected off the site, and it is an exaggeration to say that small amounts of radioactivity that were released in these cases constituted radioactive clouds.
§ Detailed scientific refutation of Dr. Martell's article will appear in American literature in the near future.
§ Marked advances have been made in techniques of containing underground explosions so that the radioactivity of only two events has been detected in areas near the Nevada test site in the past 15 months and in these cases only in minute amounts. It is significant in this regard that radioactive iodine in milk has not been detectable since mid-1963 in spite of continued underground testing. Very careful measures continue to be taken to ensure against any possibility of violation of the partial Test Ban Treaty.