Improvements Needed in Estimating Personnel Radiation Exposures from the 1946 Nuclear Test--Operation Crossroads

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IMFROVEMENTS NEEDED IN EST W TING PERSONNEL RADIATION EXPOSURES FROM THE 1346 WCLEAR TEST-- NOTICE--THIS DRAFT RESTRICTED TO OFFICIAL USE This document is a draft of a proposed report of the General Accounting Office. It was prepared by GAO's staff as a basis l o r obtaining advance review and comment by those having responsibilities concerning the subjects discussed in the draft. It has not been fully reviewed within GAO and is. therefore, subject to revision. Recipients of this draft must not show or release its contents for purposes other than official review and comment under any circumstances. At all times it must be safeguarded ' Q prel -'nt ?'Wcation of other improper disclosure of the information contained therein. This draft and ait c n - ' ~'hereof BY THE STAFF US. GENERAL ACCOUNTING OFFICE Replaces GAO Forms 331.332, and 333

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Many of the 4 2 , 0 0 0 participants in the first atmospheric nuclear weapons test, known as Operation Crossroads, were subjected to varying amounts of radiation exposure in the summer of 1 9 4 6 . Recently discovered documents raise questions about the accuracy of the Defense Nuclear Agency's radiation exposure estimates and its conclusion that no Crossroads participant was overexposed based on current radiation safety standards. The accuracy of such estimates are important because the Veterans Administration uses the Defense Nuclear Agency's radiation exposure estimates in adjudicating former Crossroads participants radiation-related disability claims. GAO was asked by the Ranking Minority Member on the Senate Committee on Veteran's Affairs to review selected aspects of radiation safety during Operation Crossroads and found that certain adjustments in the calculation of participants' radiation exposure estimates may be necessary because ( 1 ) film badges, worn by participants, provided only an approximate estimate of external radiation exposure: ( 2 ) personnel decontamination procedures evolved from a very simplistic approach to radiation protection and, as a result, participants probably received more radiation than had been recorded on the film badges they had worn: and ( 3 ) DNA's analysis of internal radiation exposure by inhalation could be underestimated by a factor of 5 or even 10. A l s o , DNA has not evaluated internal radiation exposure received through inqestion or open wounds. In addition, GAO identifies improvements needed in the reporting of participants' radiation exposure estimates to the Veterans Administration for use in adjudicating radiation disability

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Many of the 42,000 participants in the 1946 atmospheric nuclear weapons test, known as Operation Crossroads, were subjected to varying amounts of radiation exposure. Recently discovered documents by concerned private citizens raise questions about the accuracy of the Defense estimates. The Veterans Administration uses these exposure estimates in adjudicating former Crossroads participants' radiation related Because of specific Congressional concerns, GAO reviewed certain issues regarding the radiation exposure of Crossroads participants, such as the --reliability of the personnel f i l m badges used to BACKGROUND Crossroads consisted of two nuclear bomb detonations within the Bikini Island lagoon in the Pacific Ocean. After each detonation scientists and a joint task force of Army and Navy personnel Page i GAO/RCED-B5-127 RADIATION SAFETY

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entered the lagoon and examined the damage to and radiation intensitites on target ships. Approximately 42,000 personnel participated in the test from July 1 to August 10, 1946. Given the responsibility by the Secretary of Defense in December 1977 to estimate radiation doses for atmospheric nuclear weapons test report on Operation Crossroads, which concluded that personnel had not been exposed to excessive amounts of radiation. DNA's position is based on dosage amounts derived from radiation recorded on the personnel film badges worn by about 6300 out of 42,000 Crossroads participants and reconstructed external and internal radiation dose estimates for the participants. (See RESULTS IN Crossroads personnel were exposed to four BRIEF specific radiation types--internal alpha, internal and external beta, and external gamma calculation of exposure estimates for each radiation type may need adjustment because Page GAO/RCED-85-127 RADIATION SAFETY

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--film badges were not reliable for measuring both and were not worn by all Crossroads participants; --personnel decontamination procedures did not provide adequate protection for Crossroads personnel throughout the duration of the operation; --DNA's dose reconstruction analysis for internal alpha and beta radiation has not properly estimated the possible personnel exposure from three potential pathways--inhalation, ingestion and open wounds. PRINCIPAL FINDINGS DNA's radiation exposure estimates made no allowance for inaccuracies attributable to € i l m Reliability of [in badges) or its processing. GAO found and DNA Film Badges acknowledges that the recorded film badge readings would have had an overall inaccuracy of approximatell' * 30 percent because of inherent inaccuracies associbtedawith the film. Further inaccuracies normally occur during the processing and reading of the film. While i t was not possible to calculate actual Crossroads

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inaccuracies, GAO found that a mid-1950's U.S. National Bureau of Standards test showed that readings by several laboratories of film badges similar to those at Crossroads, exposed to known amounts of radiation, were inaccurate by as much as f 100 percent. GAO believes i t is unlikely that the film badge readings performed by personnel under WAh-Ud conditions at Crossroads would have been more accurate than those in DNA recognizes the film badges at Crossroads were incapable of accurately recording external beta because the portion intended to measure external beta actually recorded the effects of both external gamma and beta. DNA has not performed a dose reconstruction for external beta radiation but, instead, has judgmentally assigned doses to Crossroads participants on the basis of film badge readings, believing the badges had overestimated exposure to this type. However, GAO found cases in which personnel exposure tQ external beta radiariondmay have been underestimated or not estimated at all. Page i v GAO/RCED-85-127 RADIATION SAFETY

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Adequacy of Because DNA believes adequate personnel Personnel Decon- decontamination procedures existed from the tamination beginning at Crossroads, its radiation exposure Procedures estimates do not account for the possibility that personnel may have retained radioactivity on their bodies and clothes after work on cmtaminated target ships. In contrast GAO believes this possibility exists because decontamination procedures were evolving as experience was gained at Crossroads. For example, the earliest evidence that GAO found showing that personnel were required to shower or change clothes after returning from contaminated target ships was in decontamination procedures issued on July 3 1 , 1 9 4 6 , 6 days after the second detonation. For a time, i t also appears that heavily contaminated clothing was n o t discarded and may have been reworn after being washed, Moreover, even after comprehensive decontamination procedures were instituted, some violations of these procedures were reported. Thus, Crossroads participants were probably exposed to more radiation than accounted for by DNA. '

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Accuracy of Internal radiation exposure was not measured at Internal Exposure Operation Crossroads. DNA has estimated the Dose exposure resulting from inhaling radioactive Reconstruction materials but used a constant ratio between alpha, beta, and g a m a radiation that may have underestimated Crossroads alpha radiation by a factor of from 5 to 10. Moreover, DNA has not evaluated the internal radiation exposure to Crossroads participants from two other pathways--ingestion and open wounds. DNA believed a prohibition against food consumption aboard target ships effectively precluded the possibility of the Eirst pathway, and did not know how to calculate for open wounds. However, initial Crossroads procedures had permitted the eating of food on board contaminated target ships, making ingestion possible. RECOnnENDATIONS GAO recommends that the Secretary of Defense direct the Defense Nuclear Agency to adjust, where feasible, the Crossroads participants' --Developing a range for each Crossroads film badge reading that recognizes film and film processing

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--Reassessing the accuracy of the external beta radiation dose information for those Crossroads participants who wore film badges and, given that all Crossroads participants did not wear film badges, performing a dose reconstruction for external beta radiation; --Estimating the extent to which personnel received additional radiation exposure from a lack O K violation of comprehensive decontamination --Reevaluating and disclosing the possible errors or uncertainties associated with its analysis of internal radiation exposure by inhalation; and --Analyzing possible internal radiation exposure through ingestion or open wounds. In addition, where any of the preceding actions has been determined not to be feasible, GAO recommends that the Secretary of Defense require the Defense Nuclear Agency to document the reasons for each such determination so that the military services can provide this information' to the Veterans Adminiitration and the' affected Page v i i GAO/RCED-85-127 RADIATION SAFETY

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GLOSSARY OF TERMS Responsibilities of DNA Objectives, scope, and methodology--- 2 EVALUATION OF SELECTED ASPECTS OF RADIATION SAFETY DURING OPERATION CROSSROADS 14 Crossroads film badges provided only an approximate estimate of gamma radiation Personnel decontamination procedures seemed to evolve at Operation Crossroads 2 3 Internal alpha and beta radiation exposure has not been fully evaluated and external beta radiation exposure may have been underestimated or not estimatd at all The military services have not been required to disclose error ranges associated with reconstructed radiation exposure estimates 3 CONCLUSIONS AND RECOMMENDATIONS I MILITARY RESPONSE TO RECOMMENDATIONS OF THE RADIOLOGICAL SAFETY OFFICER I1 ALLEGATION REGARDING THE COLLECTION OF DOCUMENTS ONCE BELONGING TO THE CROSSROADS RADIOLOGICAL Target ship locations for Test Baker Actual Crossroads film badge readings Estimated Crossroads film inaccuracy

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Number of film readings higher or lower by percentage rate 22 of an unidentified target ship, Crossroads 28 Work crews use a firehose on the superstructure Work crews scrubbing down an unidentified target submarine, Crossroads 29 Figure 1: Film badge darkening pattern for beta and gamma radiation-projected by DNA Figure 2: Film badge darkening pattern f o r beta and gamma radiation-recorded for many Number of film badges issued with beta Topside radiation averages for Ship A 50 Navy calculations of an individual's gamma radiation dose range 51 Defense Nuclear Agency General Accounting Office Nuclear Test Personnel Review

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GLOSSARY OF TERMS a charged particle emitted spontaneously from the nuclei of some radioactive elements and identical with a helium nucleus. Alpha radiation is difficult to detect and its effect is lasting for years. It has a range of only a few inches in air and is incapable of penetrating clothing o r even the outer layer of unbroken skin. However, alpha radiation is a primary hazard when a charged particle of very small mass emitted spontaneously from the nuclei of certain radioactive elements. Beta radiation may travel several feet in the air before being absorbed. In more dense material, such as body tissue, beta radiation may travel up to half an inch. Clothing normally provides adequate protection from beta radiation. TherefQre, beta radiation is a hazard only when beta-emitting inaterials are either in direct contact with the skin or absorbed an instrument for measuring and registering the total accumulated dose of ( o r exposure to) ionizing

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GLOSSARY OF TERMS the measurement and recording of radiation doses and dose rates. a small piece of film encased in a metal or plastic container and used to measure radiation. ating in the nuclei of certian radioactive elements and accompanying many nuclear reactions. Gamma rays can travel great distances through air and can penetrate considerable thickness of material, although they can neither be seen nor felt by human beings except at very high intensities, which cause an itching and tingling sensation of the skin. a process by which radiation, when it encounters living tissue, transfers some of its energy to the target atoms, tearing off some or all of their electrons and leaving the atoms with a positive electrical Joint Crossroads Committee a committee established, upon distask force, to prepare and publish the official reports on that

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GLOSSARY OF TERMS National Council for Radiation Protection a private, nonprofit organization chartered by Congress which publishes reports on all aspects of one of the radioactive components of the bombs used at Operation CKOSSKOadS and an emitter of alpha a unit that expresses biological effects. Exposure to one roentgen is approximately equivalent to one a unit that expresses the amount of ionization that gamma radiation produces in air.

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F 11 wing the end f World War 11, ques ions r m ined among American military experts regarding the tactical effects of the nuclear bomb. These experts reasoned that only by testing the nuclear bomb under simulated war conditions could these questions be answered. With this in mind, the United Stares initiated nuclear weapons testing in the Pacific Ocean during 1946. The first such test, known as Operation Crossroads, consisted of two detonations--one above the water's surface and the other underwater. This operation involved the largest number of participants-- almost 42,000 Army and Navy personnel and civilian scientists--for any of the atmospheric nuclear weapons tests conducted by the United States.l It lasted from July 1 to August 10, 1946, when efforts by participating personnel to board and decontaminate the unmanned naval ships used as a target for the two bomb tests were officially terminated. About 6,300 Crossroads participants were issued a radiation dose film badge2 during one or more days of the operation. However, no one wore a film badge everyday. Lacking complete radiation dose information on each Crossroads Rarticrpant, the Defense Nuclear Agency (DNA)--under direction from the Department of Defense--has since statistically reconstructed doses from available data. DNA provides these reconstructed doses, along with available film badge readings, to the particular military service which, in turn, assigns a 1Nuclear tests conducted prior to July 1962, whether atmospheric or underwater, are considered a part of the United States' atmospheric nuclear weapons testing program because of their potential release of radiation into the atmosphere. Since July 1952, all nuclear tests conducted in the United States have been underground with most of them at the Nevada Test Site. 2 A film badge is a small piece of film encased in a metal or plastic container and used to measure radiation.

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radiation exposure to its applicable personnel. When, requested by the Veterans Administration, the particular military service provides these radiation exposure estimates to that agency for use in In May 1 9 8 3 hearings before the House Committee on Veterans' Affairs, Subcommittee on Oversight and Investigations, concerns-- based largely on information once belonging to the late Radiological Safety Officer for Operation Crossroads--were--- raised questioning the accuracy of DNA's radiation dose estimates for that operation. With approximately 500 claims on file at the Veterans Administration related to Operation Crossroads, any inaccuracy in DNA's dose estimates could potentially affect the adjudication of a substantial number of veterans' claims.3 Consequently, on August 3, 1 9 8 4 , the Ranking Minority Member on the Senate Committee on Veterans' Affairs and, subsequently, on August 14, 1 9 8 4 , the Chairman, House Committee on Veterans' Affairs, asked us to evaluate selected aspects of radiation safety during that 1 9 4 6 nuclear test operation. Operation Crossroads consisted of two 2 3 kiloton nuclear bombs detonated within the Bikini Island lagoon in the Pacific during the summer of 1 9 4 6 . The first detonation--termed Test Able--involved dropping the nuclear bomb from a …