AEC Proposed Test Plans for Cy 1957, Report to the General Manager by the DMA (AEC 944/8) AEC Test Activities for Calender Yr 1957

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BEST AVAILABLE COPY ATOMIC ENERGY COMMISSION TEST ACTIVITIES FOR CALENDAR YEAR 1957 Note by the Secretary The General Manager has requested that the attached re port by the Director of Military Application be circulated for consideration by the Commission during the week of February 11, DISTRIBUTION COPY NO. DISTRIBUTION COPY NO. Deputy General Manager 7 Asst. Gen. Mgr. Acn. 9 San Francisco Oprns,

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BEST AVAILABLE COPY PROPOSED TEST FLANS FOR CY 1957 Report to the General Manager by the Director or Military Application 1. To consider the detailed plans for the conduct of recommended operational safety criteria and estimated amounts of special nuclear materials to be expended. 2. At Meeting 125^ on December 12, 1956, the Commission considered AEC 9^/2 (Proposed Test Plans for CY 1957) and approved the conduct of a v.’eapons test operation at the Nevada Test Site during Cy 1957. 3. Plans for Operation PLUMBBOB’-as outlined In AEC 9^ and AEC 9^/2 have progressed to a point v/here a reasonably firm schedule of shots may be .presented. This schedule is given in 4, At Meetings 1246 on November 14, 1956, and 1255 on December l8, 1956, the Commission considered AEC 141/33 and approved Radiological Safety Criteria of 3.9 roentgens for the entire 1957 test series. In accordance with the Commission's BEST AVAILABLE COPY

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BEST AVAILABLE COPY dccires, operational safety criteria for Operation PLUMBBGB have been developed and arc presented in Appendix "C". 5. The v.'eapons laboratories have submitted their estimates of the amount < of special nuclear materials to be shot-expended in the test devices. These are listed in Appendix "D". Presi dential approval for the expenditure of these special nuclear materials will be requested by letter such as that in Appendix "E", ■ 6. The Division of Biology and Medicine and the Office of the General Counsel concur in the recommendation of this paper. RECCMHEHD ATX OH 7. The General Manager recommends that the Atomic Energy a. Anorove the detailed plans and shot schedule for Operation PLUMBBOB as presented in Appendices b. Approve the operational safety criteria for c. Approve the expenditure of special nuclear materials for Operation PLUMBBOB as presented in Appendix "D", subject to the approval of the d. Note that Presidential approval for the expenditure of the special nuclear materials required for Operation PLUMBBOB will be requested by letter such as that in Appendix "E". approval for the expenditure of special nuclear materials for Operation PLUMBBOB, the Joint Committee on Atomic Energy and the Military Liaison Committee will be Informed by appropriate

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BEST AVAILABLE CORY LIST OF Ell CLOSURES APPENDIX "C" - Operational Safety Criteria for APPENDIX "D" - Special Nuclear Materials to be BEST AVAILABLE COPY

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BEST AVAILABLE QOPY BACKGHCUND AND DISCUSSION 1. Planii for Operation PLUMBBOB as outlined in AEC 9^ and AEC 9^^/2 hav' progressed to a point where a reasonably firm schedule of c.uts may be presented. 2, The original tentative schedule of 26 nuclear shots (plus several one-point safety tests) has been screened as directed by the Commission with the objective of minimizing the danger of radioactive fallout on any community around the Nevada Test Site, and of decreasing the length of the operation. The screening involved deletion of shots from this operation, the redesign of test devices to reduce the yield and/or the redesign of suspension systems to raise the height of suspension above the terrain, thereby reducing the expected local fallout. 3* The resulting schedule of 24 nuclear shots is contained in Appendix "BM. The approximate starting date for the nuclear tests is May 15j 1957* with an anticipated completion date about the middle of September. Safety tests from which no nuclear yield is expected, are not listed in the schedule. They should amount to about 7 in number and will be conducted as needed, starting with a test of the plutonium hazard resulting from the warhead, DELETED in April, 1957. 4, The 24 shots remaining in the schedule may be classified as follows: BEST AVAILABLE COPY

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description and objective of each of the test devices. The ultimate weape i or v/eopens tov/ard which the tests are directed is included where applicable. It is planned that the Laboratory Directors 'Will personally present to the Commission on or about February 12, a description of, and justification for, their respective test devices. 6. Radiological Safety Criteria of 3*9 roentgens for the entire test series in 1957 was established for Operation PLUMBBOB (Decision on AEC 141/33). Based upon these criteria a recommended Operational Safety Criteria for Operation PLUMBBOB was prepared and is attached as Appendix "C". As presently scheduled, this operation, from the standpoint of control of off-site fallout, should be easier than any of the recent past operations, and no special problems are anticipated in firing the more difficult shots. The recommended operational criteria for Operation PLUMBBOB, which are basically the same as those for TEAPOT, a. The number of-nuclear shots at the Nevada Test Site in one year should be determined by laboratory requirements, as reviewed by the Division of Military Application in the light of other pertinent considerations, and should be approved by the Commission. b. Each nuclear shot programmed, ’whether AEC, military, or civil defense, should be justified individually, and the number of shots Involved should be held to the minimum consistent with BEST AVAILABLE COPYtcntially Hazardous shotc. Each potentially Hazardous shot should be separately identified, and Justification for such a shot should include plans for controlling or reducing fallout from it.

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BEST AVAILABLE COPY e. Ar.y air drop of more than 1 KT projected yield should be scheduled only after thorough evaluation of the reliability of Its fusing system, ., regard to yield and burst altitude> with maximum yield tc incorporate a reasonable allowance for These criteria are discussed more fully in Appendix "C", 7. The PLUMBBOB devices fall into two groups distinguished by the difference in quality of weather conditions which will be required. Of the two groups listed in Table I, below, Croup A requires the more exacting weather conditions because of fall out potential beyond the borders'of the test site. Shot Schedule Ease of Firing Grouping BEST AVAILABLE COPY

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divided by 1' )) or leci5 than 2.0 where a a each of the eight relatively mtre.difficult chots ban a D-factor cf 2.0 or more. The DELETED . iot baa the highect D-factor, 5.5, in Group A. This figure contrasts with D-factors of about 20.0 for the SIMON shot a- \ 12 for the HARRY shot of Operation UPSHOT-KNCTHOLE, and a design ^-factor of 10 for TURK, ZUCCHINI and APPLE I of Operation TE..P0T, The above list indicates the planned fired sequence of devices in each group. The weather requirements of Group A are such that delays are expected to occur in the firing of shots in this group. ' 8. The local fallout from the above list of shots is expected to be not more than 2440 megacuriss maximum and should be less. This relatively low figure supercedes the earlier estimate of 3500 me contained in our memorandum dated January 23, 1957, which was informally circulated to the Commissioners. The expected maximum fallout cf 2440 megacuries for PLUMBBOB may be compared with the post-series estimates of 3590 megacurics re sulting from Operation TEAPOT’S fourteen shots and 55?0 megacuries resulting from Operation UPSHOT-ICNOTHOLE1 s eleven shots. It Is interesting to note that the maximum expected local fallout from TEAPOT was about 6000 me versus the 3590 me post-series estimates, since pre-shot estimates of yields of some of the large TEAPOT shots exceeded appreciably the actual yields. 9. The reduction in expected local fallout for PLUMBBOB was accomplished by the utilisation of balloons In lieu of towers BEST AVAILABLE COPY wherever possible, the increase of tower heights, the lowering

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10. The „hots remaihins in the schedule v.’hich might be considered difficult insofar as local fallout is concerned are the Department of Defense (joint Chiefs cf Staff approved) Vleapons Effects test involving the airburst of a stockpiled DELETED vfarhead in an M3-1 air-to-air rocket (D-factor 0 if airburst as planned; or about 4.0'if airburst fuze fails and full scale detonation occurs on ground impact); and the 50 KT DELETED mockup tower shot sponsored by UCRL (D-factor 5.6). • 11. The 1*13-1 test is not as yet completely developed as to details. Representatives of the Air Force Special VJcapons Center and Field Command; Armed Forces Special Weapons Project are coordinating test plans; including the safety aspects; vfith the Nevada Test Organization and the NTS Planning Board. The present tentative plan for the MB-1 test is that the rocket will be launched from an F-89J UCAF interceptor aircraft at an altitude of approximately lS;C0Q foet MSL. No target y/ill be used; instead the missile v;ill be armed to burst at a predetermined point in space. Direction of aircraft as v;ell as actual missile launching signal will be controlled by ground M3Q-1 radar. The pilot of the delivery aircraft v;ill control pre-launch missile arming and BEST AVAILABLE COPY must be pressing an enabling svjitch before the missile launching

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BEST AVAILABLE COPY intended to l rst at about 18,000 feet I'.oL iippro/.jmatciiy 6 seconds aftei launch. The flicht path of aircraft and miasile will be such hat, if the airburst fuse failed, the missile would impact in a safe area of the Nevada Test Site. In such an event, if one-point etonaticn of the DELETED v;arhcad occurred on impact, as expected, aero v.’ould be no off-site fallout problem. However, a question ha been raised ccncernins the probability of a fullscale DELETED detonation in the event of ground impact, caused by the crushing of a component in the Air Force developed fuze prior to destruction of the charged x-unit or sphere assembly, v.’hich might effect a spherical implosion. The matter is under investigation at this time. If there is a possibility of a full-scale surface detonation on Impact, the test will be con ducted under weather conditions which will limit off-site fallout in the event of such ground detonation, even though the probability of a full-scale ground detonation may be very small. 12. The Class DELETED mockup, v;ith Its D-factor of 5.6, is the most difficult shot of the PLUMBBOB schedule. However, when compared with the SIMON shot v/ith its D-factor of 20 in Operation UPSHOT-KNOTHOLE, and the ZUCCHINI, APPLE I and TURK shots of the TEAPOT Operation, each oF which had a design D-factor of about 10, the Class DELETED is by no means an exceptionally difficult shot. It will require weather conditions suitable for firing and probably will involve a number of delays, but should present no serious fallout problem. The shot is directed toward develop ment of a full-scale DELETED • to bo tested in Operation BEST AVAILABLE COPY HARDTACK. If. the DELETED mockup were not fired In PLUMBBOB,

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BEST AVAILABLE COPY complete des.L ;n release, April 1950. Thin would probably resultin a decreas: ' yield for the DELETED weapon (possibly as much as one-third dec ease). It.is estimated that the deletion of the DELETED mockup from PLUMBBOB could delay the stockpile entry date by is much as one year (presuming a 1959 Pacific series) if tr able should be experienced v/ith the HARDTACK test. The new DELETED v/ould be affected similarly, if the DELETED were deleted from PLUMBBOB. 13. The deep underground shot experiment being designed to completely contain a 1.8 KT nuclear explosion underground will be the first test of its type to be conducted by the United States. Accordingly, every precaution is being taken in the investigation and study of the design of the experiment. The U* S. Geological Survey' is working v/ith AEC and Laboratory personnel in designing the experiment and in studying the safety aspects of the under ground shot. A separate group of highly qualified seismologists, geologists, and geo-physicists recommended by the National Academy of Sciences are being employed-as consultants to the AEC to advise on the thoroughness and completeness of our studies insofar as the problems of earth shock, ground water contamination, and triggering of disturbances are concerned, A report on the studies together with the consultants1 comments and the detailed shot plans will be presented to the Commission prior to the underground nuclear shot. 14. The amounts of special nuclear materials required to BEST AVAILABLE COPY carry out Operation PLUMBBOB, are listed in Appendix "D". In

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b. T\:o safety tests of the plutonium hazards (2) Burning of plutonium (tentative). 15. Presidential approval for the expenditure of special nuclear materials for the tests during CY 1957 v/ill be requested by letter such as that in Appendix "E". BEST AVAILABLE COPY

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BEST AVAILABLE COPY OPERATIC 'TAL SAFETY CRITERIA FOR OPERATION PDUNPEOB 1, The recommended operational criteria for Operation PLUMBBOB, which are basically the same as those for TEAPOT, a. The number of nuclear shots at the Nevada Test Site in one year should be determined by laboratory requirements, as reviewed by the Division of Military Application in the light of other pertinent considera tions, -and should be approved by the Commission. b. Each nuclear shot programmed, whether AEC, military, or civil defense, should be justified individually, and the number of shots Involved should be held to the minimum consistent with c. Each potentially hazardous shot should be separately Identified, and justification for such a shot should include plans for■controlling or reducing fallout from it. d. Marginal or more critical shots should be fired only under satisfactory weather conditions that have a high degree of predictable stability. e. Any air drop of more than 1 KT projected yield should be scheduled only after thorough evaluation of the reliability of.its fuzing system. f. Shots should be limited as follows with regard to yield and burst altitude, with maximum yield to incorporate a reasonable allowance for error: iragraph of the TE/A POT criteria

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"d. Miots should bo scheduled with more elasticity, so that non-critical shots may be fired when condi tions are not right for more critical or marginal shots. Such elasticity viill benefit from addition of 3. The following portion of paragraph c.. Appendix "A", AEC 141/25, was also deleted, as this philosophy has now been generally accepted by all test participants: "The possibility of continuing postponements and of resulting extension of series duration should be accepted. Participating organizations and units should be advised that they must accept the possibility of postponements on such shots." 4. The last sentence of paragraph g., Appendix "A", AEC 141/25, has been deleted, as the effectiveness of higher towers to reduce fallout has been proven: "Prior to detonating a 50 KT weapon from a 500-foot tower, the safety factor calculated for such a shot should be confirmed by detonating a shot of lesser 5. As a tentative figure, the So KT maximum yield for the balloon shot was taken from the air drop criteria. Studies in progress on the flash problem, and with further development of balloon techniques, indicate that we may recom mend raising, this limit at a later dat'd. 6. A sub-committee of the NTS Planning Board has developed a shot comparison method based …