No detectable amount of iodine-131, a gaseous radionuclide with a half-life of 8.1 days, was found in either group of samples, although a trace of iodine is believed present. A fourth radionuclide, xenon-133, was present in both sample groups and was also detected in field measurements during gas flow tests. The xenon-133 is not considered significant because of its short halflife of 5.3 days. No unexpected radionuclides were found in the samples. The chemical analysis of the second group of samples showed the gas to consist of 43 per cent hydrocarbons, including methane; 36 per cent carbon dioxide; 17 per cent hydrogen; and 4 per cent carbon monoxide. As a comparison, samples taken before the detonation measured 99 per cent methane and other hydrocarbons. The carbon dioxide in the samples probably results from decomposition of carbonate minerals in rock directly exposed to the blast. Gas in the Pictured Cliffs formation outside the chimney is expected to be unchanged from its pre-shot composition. Part of the second set of samples was taken before a small amount of gas, 300 MCF (thousand cubic feet), was flared and part after flaring. No significant differences were noted between the analyses of samples taken before and after flaring. Additional work planned in the Gasbuggy experiment includes further drilling into the chimney and fracture zone, gas flow and production tests, and extensive sampling and analysis of the gas. As expected, no radioactivity resulting from the Gasbuggy detonation has been found in existing wells in the vicinity of the Gasbuggy site. As a precaution, monitoring of these wells is continuing. There are no plans for commercial use of gas produced from the Gasbuggy well during the experiment. APPENDIX 12 CORRESPONDENCE AND INFORMATION CONCERNING PROJECT CABRIOLET Hon. GLENN T. SEABORG, CONGRESS OF THE UNITED STATES, JOINT COMMITTEE ON ATOMIC ENERGY, Chairman, U.S. Atomic Energy Commission, DEAR DR. SEABORG: By letter dated April 18, 1967, you advised me that the temporary postponement of Project Cabriolet caused AEC to revise the planning schedule of nuclear cratering experiments for the fiscal years 1967 and 1968. You pointed out that the net effect of the revised program was to increase the Plowshare program fiscal year 1968 cost level by $2,365,000. You further expressed the belief that the revised schedule could enable you to provide a technical feasibility determination on using nuclear explosives to excavate a sea-level canal for the Atlantic-Pacific Interoceanic Canal Study Commission to consider in its final report to the President. I understand that if Project Cabriolet is not carried out in the very near future, it will not be possible to determine the technical feasibility of using nuclear explosives to excavate a sea-level canal for the Atlantic-Pacific Interoceanic Canal Study Commission to consider in its final report to the President even with the extension of its reporting date to December 1, 1970. Please advise me as to the action you are taking to resume the nuclear excavation experiment program. Sincerely yours, JOHN O. PASTORE, Chairman. CONGRESS OF THE UNITED STATES, THE PRESIDENT, DEAR MR. PRESIDENT: Congressman Tom Morris and I attended the Plowshare Gasbuggy test in New Mexico Sunday, December 10, 1967. I am sure you have been informed that the nuclear detonation was successfully carried out. We are hopeful that in the final analysis such experiments will prove the economic goal of doubling our natural gas resources by using nuclear explosives in this way. Six years ago last June the launch of a nuclear powered navigational satellite was delayed by those who feared adverse publicity. You may remember that I enlisted your support, when you headed the Space Council, in obtaining the approval of President Kennedy to launch the satellite. The satellite was launched and is still being used by the Navy as a navigational aid. This is the first use of nuclear power in space and this satellite is now the oldest active satellite still in orbit. I am hopeful that the planned Plowshare excavation project, Cabriolet, can be carried out without further delay. We need the information to open up a host of peaceful uses of nuclear explosives. There is reason to believe that the U.S.S.R. has been conducting similar type experiments. Since the Cabriolet explosive is a comparatively clean one, there should be little risk of radiation venting. I am hopeful that we will be able to do everything possible to carry out the test which has such a great potential for opening up many additional peaceful uses of nuclear energy. Sincerely yours, CHET HOLIFIELD, Vice Chairman. U.S. ATOMIC ENERGY COMMISSION, Mr. JOHN T. CONWAY, Executive Director, Joint Committee on Atomic Energy, Congress of the United States DEAR MR. CONWAY: Attached for your information is a copy of an announcement concerning plans to conduct Cabriolet a peaceful nuclear detonation for developing excavation technology. The announcement was distributed locally by our Nevada Operations Office last night, January 25, 1968. Sincerely yours, ROBERT D. O'NEILL, Director, Congressional Relations. [Attachment] PRE-CABRIOLET ANNOUNCEMENT The Atomic Energy Commission plans to conduct tomorrow at its Nevada Test Site an experiment as part of its Plowshare program in which excavation technology is being developed for peaceful purposes. The experiment-called Project Cabriolet—will be the next step in a continuing program to develop nuclear excavation technology and will involve a low-yield (2.5 kiloton) nuclear explosion. Cabriolet originally was scheduled to be conducted early last February but was postponed temporarily. Background information on Cabriolet is attached. BACKGROUND INFORMATION ON PROJECT CABRIOLET I. Introduction The Atomic Energy Commission in its Plowshare program is studying and developing a technology for using nuclear explosives for peaceful purposes. With a tremendous amount of energy in a relatively small package, nuclear explosives may make feasible projects which otherwise would be uneconomic or technically impractical. Since the Plowshare program was established in 1957, AEC has conducted 19 nuclear field experiments and extensive laboratory research and development, and has derived data from numerous nuclear tests conducted for other purposes. From this work an understanding of the basic phenomena of underground nuclear explosions is evolving. When a nuclear explosion occurs very deep underground in hard rock it produces a large amount of broken rock, but does not break the surface of the ground. When the explosion occurs at a lesser depth, a crater is formed in the surface. The AEC in its Plowshare program is currently studying in more detail the basic effects of explosions in a variety of geologic media and under a variety of conditions, and how these effects can be put to use. The ability of an underground nuclear explosion; at the proper depth, to break and move-in one step-vast amounts of earth and rock offers potential for undertaking otherwise impractical earth-moving projects. Studies thus far, mainly based on results with chemical explosives, indicate that nuclear explosives might be used for large-scale projects such as constructing harbors, water reservoirs, ship canals, and highway and railroad passes through mountain ranges. One potential application, the use of nuclear explosives to dig a sea-level canal, is being investigated in detail as part of a special study by the Atlantic-Pacific Interoceanic Canal Study Commission. As part of its responsibility under Public Law 88-609, the Canal Study Commission will recommend the best route and method of construction for a canal. Recognizing the potential of a safe and economic excavation technology using nuclear explosives, the AEC has been actively engaged for several years in developing such a technology. To date, in addition to several hundred cratering experiments with chemical explosives, several nuclear cratering experiments in a variety of media and with energies up to 100 kilotons have been conducted. However, considerable experimental data are still needed before the technology is fully developed. Cabriolet is the next step in this development program. II. Project Cabriolet The AEC plans to conduct Project Cabriolet at its test site near Las Vegas, Nevada. The explosion is expected to release energy equivalent to nearly 2,500 tons (2.5 kilotons) of TNT. The explosive will be placed and detonated 170 feet underground and will form a crater with an expected depth in the range of from 57 to 117 feet, and a diameter of from 260 to 420 feet. The explosive will be put in place through a 48-inch diameter, uncased hole which will be stemmed, or sealed, with dense sand and concrete plugs set into the surrounding rock. This method of sealing the emplacement hole has been successfully used in previous cratering experiments, both nuclear and chemical. This project is an important step in providing essential data on basic cratering effects from a nuclear explosion occurring at what appears to be the best depth underground in a hard, dry rock. Project Sedan, conducted in July 1962, was the first major nuclear excavation experiment conducted in the Plowshare program. It released 100 kilotons of energy but was carried out in desert alluvium, a loose sand and gravel material. Although Cabriolet is 40 times smaller than Sedan, it will be an important step forward since it will be six times larger than the last experiment emplaced at the best cratering depth in hard rock-Project Danny Boy-which released 0.4 kilotons of energy. The determination of cratering effects at larger yields in hard rock is important because it is expected to be the most frequently encountered material in future excavation projects. The information obtained from the experiment will be used in developing further the understanding of how craters are formed. In turn, this understanding is expected to result in increased confidence in predicting the characteristics of craters in other types of rock and from larger explosions. Data from field experiments, such as Cabriolet, combined with the most advanced knowledge of the physical and chemical properties of rocks and explosion phenomena, provide the input to complex computer calculations which produce a description of the entire cratering process. Thus, this cratering experiment will improve the computer calculations and, hence, the overall description of the cratering phenomenon. Cabriolet will supply data with which to plan the future developmental program and to support on a timely basis the current feasibility studies of the Canal Study Commission. Cabriolet, like previous underground cratering explosions, will release only a small amount of radioactivity. Most of it will be trapped underground or in the earth and rock debris deposited near the crater. The experiment has been so designed that almost all the little remaining radioactivity will be deposited within the controlled area. The plan includes awaiting very precise weather conditions to assure public health and safety. These weather conditions dictate the exact date of the experiment. These and other precautions will assist the United States in meeting its obligations under the 1963 Treaty Banning Nuclear Weapons Tests in the Atmosphere, in Outer Space, and Under Water. Some I may be deposited off the test site; however, because of the experimental nature of the test, the exact concentration at a given location cannot be predicted. I1 can be deposited on grass, concentrated in milk by cows which eat the grass and taken up by the thyroid glands if people drink the milk. For this reason, Cabriolet is scheduled to be conducted before the spring grazing season begins, so that any I, which has only an eight day half-life, will have decayed before any milk problem can occur. Note to Editors and Correspondents: U.S. ATOMIC ENERGY COMMISSION, The following announcement was dictated to the wire services at Las Vegas, Nevada, at 5:00 p.m., EST, Friday, January 26: "The Atomic Energy Commission conducted a low-yield nuclear excavation experiment at its Nevada Test Site on January 26, 1968. The experiment was part of the Commission's Plowshare program to develop the peaceful uses of nuclear explosions. "The nuclear explosion had a yield of about 2.5 kilotons (equivalent to 2500 tons of TNT) and was buried at a depth of 170 feet. It produced a crater about 125 feet deep and 400 feet in diameter. This experiment, called Project Cabriolet, was a step in the Commission's continuing program to develop nuclear excava tion technology. This experiment will provide information about cratering effects in hard dry rock." |