59. Letter from Seaborg to President Kennedy, October 101
Dear Mr. President:
The enclosure to the letter of September 20 from Secretary Gilpatric and myself discussed the pros and cons of different environments for testing nuclear weapons. It included recommendations that preparations be made to give an immediate readiness posture for low-yield atmospheric tests in Nevada and a 3-months’ readiness posture for large-scale tests at Eniwetok, and that attention be given to the possibility of conducting atmospheric tests through the medium of completely air-borne operations. In my letter of October 7, I pointed out that any appreciable speed-up in our presently-planned program could be accompanied only by going to atmospheric testing.
The present letter will discuss various aspects of testing in the three locations mentioned above, including technical feasibility for various kinds of tests, time scales, costs, etc., together with the possible effect on the schedule of our presently-planned program, should such methods be adopted. A letter of October 9, 1961 from Secretary Gilpatric describes possible tests of mutual interest as well as certain complete systems demonstrations primarily of concern to the Department of Defense.
The earliest possible atmospheric tests of developmental significance are some of those now proposed for the approved NOUGAT Program which could be accomplished from one to two months ahead of the current schedule by using tethered balloons at the Nevada Test Site. (Such tests are, of course, subject to possible delays due to weather.) Balloons are on hand. Rehabilitation of the ground handling equipment and training of the crews are the pacing factors of the steps required to achieve readiness; these steps will take from 10 days to two weeks. Sampling aircraft and diagnostic equipment can be ready within the same time frame.
An advance of as much as four or five months in the schedule for some of the tests in the follow-on program enclosed with my letter of September 19, 1961 could also be accomplished by use of the balloon technique. Toward the latter part of this program, testing could be conducted much more rapidly if not inhibited by the lengthy process of preparing underground sites. The cost of balloon tests is appreciably [Typeset Page 173] less than of those conducted [Facsimile Page 2] underground, or those utilizing towers, but there is some sacrifice in the technical information attainable.
A speed-up of those tests involving yields too large to be conducted in the atmosphere in Nevada could be accomplished by utilizing an air drop technique over the Pacific, again at some sacrifice in the technical information obtainable. Proof tests of bombs, which do not require extensive diagnostics, could begin in from two to four weeks. Tests of missile warheads or developmental devices requiring the fabrication of drop containers could begin in two to three months. This sort of wholly air-borne operation, which would be conducted from air bases on Hawaii, would require aircraft for dropping the devices, for radio-chemical sampling and for air-borne diagnostics such as “bangmeters,” photography and other measurements. We are assured that these aircraft and the necessary manpower are available and require only adequate priority to preempt their use.
This technique could be used for several of the tests in the follow-on program (letter of September 19, 1961). Certain of these tests (e.g., the Pershing and second generation Minuteman warheads) originally planned as low-yield mock-up tests might be conducted at intermediate or full-scale yields. This technique would also permit the introduction of some development testing involving yields so large as not to have been included in the follow-on program. The method would also be applicable to proof testing medium and large-yield weapons not suitable for underground testing.
The cost of such air-borne drop tests is estimated to be from 250 to 300 thousand dollars per event to the AEC, plus comparable DOD operating costs.
For those large-yield tests involving such complex and precise instrumentation as to require a land base, it would be necessary to open up an Island Site in the Pacific. The Eniwetok or the Johnston Island installations could be rehabilitated for this purpose. The former is larger and would permit a greater variety of tests; the latter has an available missile-launching site. To prepare the Eniwetok installation would entail removing tropical growth, rehabilitating buildings, roads, and docks, and reconditioning the utilities and other mechanical support elements. Some minor new construction would be required. As an alternative, it might be possible to negotiate with the U.K. for the use of Christmas Island, which we understand has been kept in stand-by condition and which [Facsimile Page 3] has the advantage of not being in the Trust Territory. In any event, such an island operation would require activation of a military task force to furnish adequate logistic support. From four to six months would be required to accomplish all the steps necessary to begin a meaningful test series. Several million dollars would be required for initial rehabilitation of either of our own sites. The [Typeset Page 174] extent of further investment required would depend on the scope of the test series to be conducted. It has been our previous experience that AEC costs alone at Eniwetok averaged about two million dollars per event for an extended series of tests.
In summary, it is clear that acceleration of relatively simple tests, in the present program, can be accomplished by testing on tethered balloons at the Nevada Test Site, that larger-yield proof tests and certain developmental tests can be carried out by a completely air-borne operation within the next few months, but that it will take at least six months and a major operation to open up a Pacific Test Site for an extended development test program.
These three methods of atmospheric testing together with our underground capability would permit flexibility of response to the wide variety and frequent surprises of the developmental program.
I am sending copies of this letter to Secretary Rusk, Secretary McNamara, Mr. Bundy, Dr. Wiesner, Mr. Dulles, and Mr. Foster.
Respectfully,
- Technical aspects of nuclear testing at Nevada, at Eniwetok, and via airborne medium. Secret. 3 pp. Kennedy Library, National Security Files, Subjects Series, Nuclear Testing, 9/27/61–10/10/61.↩