DISCLAIMER The following is a staff memorandum or other working document prepared for the members of the Advisory Committee on Human Radiation Experiments. It should not be construed as representing the final conclusions of fact or interpretation of the issues. All staff memoranda are subject to revision based on further information and analysis. For conclusions and recommendations of the Advisory Committee, readers are advised to consult the Final Report to be published in 1995. TAB L MEMORANDUM TO: Members of the Advisory Committee on Human Radiation Experiments FROM: Advisory Committee Staff DATE: August 31, 1994 RE: Intentional Releases of Radioactivity In its Charter, the Advisory Committee is charged with investigating a list of thirteen environmental releases identified in a report by the General Accounting Office1{1 General Accounting Office, Fact Sheet for the Chairman: Committee on Governmental Affairs, U.S. Senate, "Examples of Post World War II Radiation Releases at U.S. Nuclear Sites," GAO/RCED-94-51FS, November, 1993. This Report is included in Briefing Book 2.} along with "any other similar experiments which may later be identified by the Interagency Working Group." The Advisory Committee is also charged more generally with investigating "Experiments involving intentional environmental releases of radiation that (A) were designed to test human health effects of ionizing radiation; or (B) were designed to test the extent of human exposure to ionizing radiation. "The Advisory Committee and staff have been gathering and reviewing information on the thirteen intentional releases listed in the Advisory Committee's Charter (the "Charter Thirteen") and on other releases that have since come to light. A preliminary list of these releases was included in the previous Briefing Book (Briefing Book 5, Tab J). This memo expands on that list by providing more information on some of the previously listed events (Dugway, Los Alamos, and the Idaho iodine-131 releases listed in the 1986 Markey Report) and by adding some events that were not previously listed. This expanded list includes the identification of larger series which include test series described in the GAO Report. The additional information available to the Committee provides a clearer picture on some issues, although it is difficult to reach general conclusions. The amount of radioactivity released in particular events varies widely, from under a curie for the 1963 release of iodine-131 from Hanford to tens of thousands of curies for the 1949 Green Run. By comparison, the radioactive fallout from an atmospheric nuclear bomb test is typically thousands of times greater still. The purposes of these tests also vary widely, and include tests of weapons, of radiation detection equipment, of reactor safety and accident risks, and of the transport of radioactive materials in the environment. The Committee still has few planning documents, which might show plans to collect data on human subjects or indicate the extent of safety and notification 1 procedures to mitigate potential risks. In some cases there is clear documentation of intentional human exposures for experimental purposes, including the 1963 iodine-131 releases at Idaho and Hanford and the 1965 Kiwi nuclear rocket test. The available documents also provide incomplete indications of measures taken to protect test participants and the general public. Analytical Questions As the Committee and staff have become aware of an expanding list of intentional releases, we have developed a set of questions whose answers may determine the level of Committee interest in particular releases. Unfortunately, the documents in hand rarely provide answers to all these questions: 1) What was the purpose of the release? (e.g. bomb testing, reactor testing, long-range detection, environmental study) 2) How much radioactivity was released and in what form? 3) Was radiation monitored on- and off-site? Who was responsible for this monitoring? 4) Were there human biomedical studies in connection with the release(s)? 5) Were participants and bystanders notified in advance of potential risks? 6) Were measures taken to minimize risks to participants and bystanders? Radiological Warfare Tests at Dugway Proving Ground, Utah The GAO report refers to six tests of radiological warfare bombs at Dugway Proving Ground, Utah to disperse radioactive materials. The report describes a first series of two tests in October and November 1949, using pellets of Tantalum-182. It also refers to four other tests, but states that documentation of these tests was unavailable. These tests were conducted by the Army Chemical Corps, the Atomic Energy Commission, and the Air Force. Documents provided by the Department of Defense about radiological warfare tests at Dugway include descriptions of five additional series of munitions tests (July-September 1950, May 1951, November 1951, May 1952, and August-September, 1952). These reports describe 13 tests involving 51 munitions, some dropped from aircraft and others released from the ground. The general purpose of these tests was to develop ways to disperse radioactive materials so that they would contaminate large areas (up to 3.2 square miles in one test) in a uniform and predictable way. Reports of these tests describe radiation levels in the range of a few mr/hr, with "hot spots" of 50-400 mr/hr. They do not describe possible off-site monitoring or contamination, but some describe measurements of radioactivity dispersed in the atmosphere (less than 1% of the total) and by weathering ("no detectible effect"). 2 Additional documents describe tests of methods for decontaminating affected grounds and reclaiming land used in radiological warfare tests, including surface removal, plowing, grading, and covering. Two other reports describe detailed measurements of radiation on contaminated sites at Dugway, and tests of building structures and materials for shelter against nuclear and radiological warfare. A final report analyzes a variety of radioisotopes for suitability as radiological warfare agents. These reports provide no indication that humans might have been used as subjects in radiological warfare experiments at Dugway. The experimental protocol directed those responsible for setting up, carrying out, and following up on the tests to follow procedures outlined in the Chemical Corps' "Safety Regulations for the Technical Command" and "Standard Operation Procedure for Work Involving Radiation Hazards." No violations of these guidelines were reported. Other documents provided by the Department of Defense contain a discussion of whether and how to notify the public about the radiological warfare field testing program set to begin at Dugway. Some officials argued for a public statement to avoid the possibility of uranium prospectors encountering contaminated grounds (Attachment 1): "A properly worded statement by the Secretary of the Army seems preferable to the sometimes irresponsible scare stories emanating from poorly informed reporters. A peacetime operation of this type will probably draw public notice sooner or later regardless of the security procedures adopted. The territory being used for the tests is being surveyed continually by prospectors for radioactive ore, so that an unusual amount of radioactivity found by such prospectors would certainly draw attention to the area." A press release was prepared, dated October 10, 1949, (Attachment 2) stating that these tests would be conducted for defensive purposes and assuring that "procedures have been set up which will insure the safety of the personnel conducting the tests and for all of the surrounding area." However, a later memo (Attachment 3) states that "it is considered inadvisable to release information on radiological warfare." Radiation Releases from Los Alamos The GAO report cites four atmospheric tracking tests at Los Alamos in 1950. Three of these involved the study of implosion and of the dispersal, fallout, and radioactive decay of materials from the explosion of simulated nuclear devices. Two clouds passed over sparsely populated areas, and one was tracked as far as the town of Watrous, New Mexico, 70 miles east of Los Alamos. A fourth test used an unidentified 400-curie radioactive source, which was detected a few miles away. Los Alamos has since identified the first three as part of a series of 254 Radioactive Lanthanum (RaLa) tests, conducted in the Bayo Canyon near Los Alamos between 1944 and 1962 (Attachment 4). The RaLa tests were diagnostic tests of the implosion mechanism of a nuclear fission bomb. Inside the high explosive shell, a core of Lanthanum-140 replaced the usual plutonium core, 3 and gamma radiation from the Lanthanum provided information on the course of the implosion. Los Alamos has provided some early planning memos on these tests, as well as periodic reports of its H (Health) Division, which include occasional reference to radiation monitoring at Bayo Canyon. The documents that would support a more detailed accounting are unlikely to be declassified because they contain information on weapons design and diagnostics. Rather than attempt to declassify these documents, Los Alamos states that it is preparing a report that would include the information that can be released. This report would include a listing of events and a worst-case dose reconstruction based on a sampling of events, using known information about the test, the weather, and the terrain. However, the Department of Energy does not plan to release the source terms for the underlying calculations -- which would include the total radioactivity and the extent of the resulting cloud -- because they would provide information on weapons design and testing. According to Los Alamos, none of the RaLa documents contain any information suggesting that biomedical experiments were performed, planned, or contemplated in conjunction with any of these tests. The only health-related references we have located are those from Division H-1, which deal with monitoring and safety. Los Alamos has also stated that the airborne tracking tests performed in 1950 were add-ons to the RaLa tests, in which other groups took advantage of these releases to test radiation detection equipment. Los Alamos states that there were no routine public notices of RaLa tests, nor were there routine safety measures such as road closures. In later years there was routine (if not universal) meteorological monitoring to reduce the risk that radioactive materials would drift toward populated areas (Attachment 5). Staff is seeking the declassification of planning and other documentation relating to possible human testing in conjunction with the RaLa tests. Pantex A March 19, 1956 telegram (Attachment 6) from the AEC Santa Fe operations office to AEC Headquarters in Washington discusses the risks of a planned RaLa test at the Pantex plant in Amarillo, Texas. The memo appears to equate these tests with the RaLa implosion tests at Bayo Canyon near Los Alamos. The telegram argues that the containment facility at Pantex eliminates almost all risk of significant releases and exposures to humans, particularly in comparison to Bayo Canyon. The telegram also suggests a public release about the facility, which would describe the use of radioactive tracers in high explosive tests. Iodine-131 Release(s) from Hanford The Committee has received documentation of three intentional releases of I-131 at Hanford, in addition to the Green Run. A July 1958 Hanford memo includes a reference to the intentional release in 1944 of several hundred curies of I-131, "so that the Army could determine the dispersion and transport characteristics of the atmosphere" and states that this was a "one-shot experiment." This occurred in the context of the release of hundreds of thousands of curies of I-131 from Hanford's wartime operations. 4 An intentional release on July 25, 1963 appears to be a radioecology study, designed to understand the transport and biological uptake of radioactive materials in the environment. This release involved the release of 150 millicuries of activity, in the form of small ampules of I-131 provided by Oak Ridge. Researchers observed concentrations of radioiodine in the air, on vegetation, in animals, and in two human volunteers. One of the volunteers was the "Senior Engineer" who wrote reports on this event. The measured thyroid activity was 240 picocuries in one volunteer, 340 picocuries in the other, corresponding to thyroid doses of roughly .2-.3 millirad. The documentation for the September 13-14, 1962 release is more fragmentary, but appears to reflect a different type of test. This experiment released 8.3 Curies of I-131 over a period of approximately 18 hours, by dissolving spent reactor fuel at a controlled rate at Hanford's Redox plant. A redacted and excerpted report describes a variety of methods used to detect the plume, including air sampling by aircraft. I-131 Releases in Idaho Between 1963 and 1968, the National Reactor Testing Station (NRTS) in Idaho (now the Idaho National Energy Laboratory -- INEL), a facility of the Atomic Energy Commission, conducted a series of Controlled Environmental Radioiodine Tests (CERT). This series apparently involved at least 21 sets of releases [1967 CERT Progress Report, p. 39] of I-131 gas at the NRTS Experimental Dairy Farm (EDF). As cited in the 1986 Markey report, during the first CERT seven human volunteers drank milk from cows that grazed on a contaminated pasture. Dr. John Harbert of the Advisory Committee Staff estimates the thyroid doses to these volunteers as .3-.62 rad. During two later tests three and then seven volunteers were placed downwind during the releases. The reports to not say whether any volunteers participated in more than one experiment. Researchers monitored the passage of iodine through each phase -- atmosphere, grass, cow, milk, and human -- and compared the effectiveness of absorption through inhalation versus ingestion. The Centers for Disease Control are sponsoring a dose reconstruction survey to estimate the dose to people in nearby communities. Fission Product Field Releases From July to October, 1958, the Armed Forces Special Weapons Project (AFSWP) carried out a series of intentional releases of radioisotopes at NRTS in Idaho and Dugway in order to understand the potential effects of an accident involving nuclear reactor core meltdown. According to Stannard (Attachment 7), the tests were part of the Aircraft Nuclear Propulsion program (ANP -- this is an alternate name for NEPA -- Nuclear Energy for the Propulsion of Aircraft). Several other institutions took part, including a group from the University of Rochester that carried out biological studies in conjunction with the tests. 5 The tests involved vaporizing spent reactor fuel, both "green" and "aged." The biological experiments involved measuring radioactivity absorbed in the lungs and digestive tracts of rats and dogs at various downwind locations. Stannard provides no information on the total amount of activity released or possible hazards to humans, and offers no indication of biomedical experiments on human subjects. Idaho Reactor Excursion Test A CERT I-131 release (see above) report includes a reference to meteorological monitoring at a Special Power Excursion Reactor Test (SPERT I) in 1962. The terminology suggests that this was a simulated reactor accident in which material could have been released into the environment. Kiwi Nuclear Rocket Tests Between 1955 and 1972, the Department of Energy undertook a series of 20 tests at the Nevada Test Site of a reactor-powered rocket. The overall research and development program was a joint effort involving NASA, and appears to have had various names, including Rover and NERVA (Nuclear Energy for Rocket Vehicle Applications). Stannard reports that test series was named "Kiwi" after the flightless bird of that name, because the tests were ground tests. The cloud sampling history refers to "jet- assisted takeoff" but this appears to refer to the sampling aircraft. The nuclear rocket concept uses a reactor to heat hydrogen gas, which is expelled through a rocket nozzle to propel the rocket forward. In principle, this could be done without releasing large amounts of radiation and radioactive materials, but this would require safety systems and shielding that add to the weight of the rocket. The actual reactor design used small (100-200 micron) particles of Uranium Carbide (UC2), and resulted in substantial emissions of radioactive particles. According to Stannard (p. 1235), one test released 11,000 Curies. On August 24, Representative Markey wrote to Secretary O'Leary about the Kiwi tests (Attachment 8). The Markey letter cites several documents and incidents. Two of these incidents -- Kiwi A-Prime and Kiwi A Three -- involve aircraft and their crews flying through the exhaust cloud from a test in 1960. The History of Air Force Atomic Cloud Sampling (also discussed in Tab F) also refers to this incident. Some members of the air crews swallowed dosimetry capsules or underwent Human Counter studies at Los Alamos before and after the flights. The sources differ on whether neutron doses were measured for air crews. According to the cloud sampling history, "Neutron radiation dosages were unrecorded because of the instantaneous nature of such emanations." (Attachment 9, p. 290) The Los Alamos report states that the specific doses were omitted "for classification purposes," but adds (Attachment 10 p. 338): "Of the [] film capsules swallowed ~3 hours prior to the mission, [] were recovered and [] undamaged by gastric contents. Readings were roughly 2/3 of the externally worn film badge. The polyethylene jugs filled with 10 times normal physiological saline were installed in the aircraft in anticipation of the possibility that the neutron dose to crew member[s] would be below the measurable limits of the LASL Human Counter. This, however, was not the case, and the actual body counts of the crew members were used to indicate their thermal neutron dose." 6 The Markey letter also cites a document (Attachment 11) that describes the Kiwi-TNT (Transient Nuclear Test) in 1965, in which a simulated accident released a radioactive cloud that was tracked by aircraft as it passed southwest over Los Angeles. 157 downwind residents were issued film badges, and milk and vegetation samples were collected in downwind areas. Aircraft tracked the radioactive cloud downwind over Los Angeles to the Pacific Ocean. One-Point Safety Tests Stannard also refers to numerous one-point safety tests of fission warheads at the Nevada Test Site. These were tests to determine whether the accidental detonation of the high explosive in a warhead would produce a nuclear yield. In some cases, there were biological experiments on animals downwind of the test, including a series at Operation Roller Coaster in 1963, but there is no evidence of experimentation on humans. These tests dispersed substantial quantities of plutonium, which presents a significant hazard if inhaled, but whose alpha emissions are not detected by most monitoring methods. A May 4, 1956 (Attachment 12) notes the high levels of plutonium at the Nevada Test Site: "Plutonium contamination levels at the Nevada Test Site are believed to range as high as 100 times the maxim "safety level" for laboratories." Oak Ridge and Hanford Air Sampling An excerpt (Attachment 13) from an Oak Ridge memo on "An Aerial Survey of Radioactivity Associated with Atomic Energy Plants"describes a series of 20 flights at Oak Ridge and 3 at Hanford. This excerpt does not indicate in what year the flights took place, or whether the radiation detected resulted from intentional releases or routine plant operations. Other Releases The Committee has received no further documentation on the other intentional releases described in previous Briefing Books. These include:* The Green Run at Hanford in 1949.* Radiological Warfare Experiments at Oak Ridge in 1948.* Radiosodium releases at Rochester in [1944].* Project Chariot -- injection of radioactive soil in Alaska in [year].* Releases of uranium hexafluoride at the Paducah, Kentucky plant in [year]. 7 * Various possible releases described by the Defense Nuclear Agency (see Briefing Book 5, Tab J). 8 List of Attachments: Attachment 1: October 3, 1949 memo urging the public release of information on radiological warfare field tests Attachment 2: October 10, 1949 draft press release on radiological warfare field tests at Dugway Attachment 3: January 9, 1950 memo urging continued secrecy about radiological warfare tests Attachment 4: Description of Radio Lanthanum (RaLa) Experiment Attachment 5: H-1 Program for Bayo Canyon Shot Attachment 6: Telegram on publicity for Pantex explosive tests. Attachment 7: Excerpt from Stannard on fission product field releases Attachment 8: Letter from Representative Markey to Secretary O'Leary on Kiwi tests Attachment 9: Excerpt from History of Air Force Atomic Cloud Sampling Attachment 10: Los Alamos Report on dosimetry if Kiwi air crews Attachment 11: Los Alamos report on 1965 Kiwi simulated accident Attachment 12: Memo on plutonium contamination at the Nevada Test Site. Attachment 13: Aerial Survey of Radioactivity Associated with Atomic Energy Plants 9