Defense Threat Reduction Agency Defense Threat Reduction Information Analysis Center 1680 Texas Street SE Kirtland AFB, NM 87117-5669 DTRIAC SR-12-001 T CASTLE BRAVO: FIFTY YEARS OF LEGEND AND LORE R A Guide to Off-Site Radiation Exposures O January 2013 P Distribution A: Approved for public release; distribution is unlimited. E Trade Names Statement: The use of trade names in this document does not constitute an official endorsement or approval of the use of such commercial hardware or software. This document may not be cited for purposes of R advertisement. Authored by: L Thomas Kunkle Los Alamos National Laboratory, Los Alamos, New Mexico A and Byron Ristvet I Defense Threat Reduction Agency, Albuquerque, New Mexico C E P S Form Approved OMB No. 0704-0188 REPORT DOCUMENTATION PAGE Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE 3. DATES COVERED (From-To) 31 January 2013 Special Report 1954 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Castle Bravo: Fifty Years of Legend and Lore DTRA-02-03-D-0002 A Guide to Off-Site Radiation Exposures 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR (S) 5d. PROJECT NUMBER Thomas Kunkle 5e. TASK NUMBER Los Alamos National Laboratory Byron Ristvet Defense Threat Reduction Agency, J9CXT 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) 8. PERFORMING ORGANIZATION REPORT NUMBER Defense Threat Reduction Agency DTRIAC SR-12-001 Defense Threat Reduction Information Analysis Center LA-UR-04-1400 1680 Texas St. SE, Building 20676 Kirtland AFB, NM 87117-5669 9. SPONSORING/MONITORING AGENCY NAME(S) AND 10. SPONSOR/MONITOR’S ACRONYM(S) ADDRESS(ES) Defense Threat Reduction Agency 11. SPONSOR/MONITOR’S REPORT No. 8725 John J. Kingman Road Fort Belvoir, VA 22060-6201 12. DISTRIBUTION/AVAILABILITY STATEMENT Distribution A: Approved for public release; distribution is unlimited. 13. SUPPLEMENTARY NOTES 14. ABSTRACT This report is a narrative history and guide to primary historical references concerning the CASTLE BRAVO nuclear test of 1 March 1954. Detonated at Bikini Atoll in the Marshall Islands, BRAVO was the largest-yield American nuclear explosion. Also, it was the only American nuclear test to result in prompt harm to civilian populations. Radioactive fallout arrived within hours on several nearby populated islands, necessitating emergency evacuations of Rongerik, Rongelap, and Utirik atolls, and resulting in radiation overexposures to approximately 665 island residents. This report focuses on the circumstances that resulted in radioactive contamination of the inhabited atolls. No attempt is made to address, in any detail, the larger issue of the effects of BRAVO on and around the shot site at Bikini Atoll. 15. SUBJECT TERMS CASTLE BRAVO, SR-12-001, legend, lore, nuclear test, radioactive fallout, radiation exposure, contamination, evacuation, Bikini Atoll, Eniwetok, Enewetak, Rongerik, Rongelap, Utirik, Marshall Islands, House Committee Hearing, Joint Task Force, Pacific Proving Ground, weather, winds, sampling 16. SECURITY CLASSIFICATION OF: 17. LIMITATION 18. NUMBER 19a. NAME OF OF ABSTRACT OF PAGES RESPONSIBLE PERSON: Byron Ristvet SAR 195 a. REPORT b. ABSTRACT c. THIS PAGE 19b. TELEPHONE NUMBER (include area code) UNCLASSIFIED UNCLASSIFIED UNCLASSIFIED 505-846-8680 Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. 239.18 January 2013 CASTLE BRAVO: Fifty Years of Legend and Lore DTRIAC SR-12-001 LA-UR-04-1400 CASTLE BRAVO: Fifty Years of Legend and Lore A Guide to Off-Site Radiation Exposures DTRIAC item 22-C-93 Figure 0–1. Utirik Island village seen from a raft bringing radiation safety monitors to shore, 3 March 1954 By Thomas Kunkle Los Alamos National Laboratory, Los Alamos, New Mexico and Byron Ristvet Defense Threat Reduction Agency, Albuquerque, New Mexico CASTLE BRAVO: Fifty Years of Legend and Lore iii January 2013 CASTLE BRAVO: Fifty Years of Legend and Lore Table of Contents REPORT DOCUMENTATION PAGE ............................................................................. ii CASTLE BRAVO: Fifty Years of Legend and Lore .................................................... iii Acknowledgments......................................................................................................... x 1.0 Introduction ......................................................................................................... 1 1.1 The Marshall Islands and the Pacific Proving Ground ............................. 4 2.0 Weather ............................................................................................................. 36 2.1 Winds and Fallout .................................................................................. 38 2.2 The Pate-Palmer Report ........................................................................ 42 3.0 Fallout Predictions ........................................................................................... 48 3.1 The BRAVO Fallout Pattern ................................................................... 58 3.2 Lower Level Wind Effects ...................................................................... 69 3.3 A Shift of the Winds ............................................................................... 76 3.4 Yield Effects ........................................................................................... 77 3.5 Testing Techniques ............................................................................... 80 3.6 Device Considerations ........................................................................... 86 3.7 The Danger Area ................................................................................... 87 4.0 Radioactive Contamination ............................................................................. 89 4.1 Airborne Radiological Surveys ............................................................... 90 4.2 The HASL Fixed Instrument Network .................................................... 93 4.3 Soil and Water Sampling ....................................................................... 93 4.4 Summary of Radiation Exposures ......................................................... 96 4.5 Radioactive Contamination from Operation IVY .................................... 99 4.6 The Nationwide Radiological Study ..................................................... 100 4.7 Comments on the Operation CASTLE Radiation Exposure Records .. 102 5.0 Evacuation of the Off-Site Atolls ................................................................... 105 5.1 Rongerik .............................................................................................. 112 5.2 Rongelap ............................................................................................. 114 5.3 Utirik .................................................................................................... 121 5.4 Ailuk ..................................................................................................... 126 5.5 The Fortunate Dragon ......................................................................... 127 5.6 The Project 4.1 Medical Research Studies .......................................... 130 5.7 Evacuation Planning ............................................................................ 135 5.8 Record Keeping ................................................................................... 136 6.0 The House Committee Hearing ..................................................................... 141 6.1 Comments on the Statement by Mr. Merril Eisenbud .......................... 142 6.2 Comments on the Statement by Mr. Jonathan Weisgall ...................... 145 6.3 Comments on the Statement by Mr. David M. Weiman ....................... 148 Table of Contents v January 2013 CASTLE BRAVO: Fifty Years of Legend and Lore 6.4 Comments on the Statements by Dr. Steve Simon and Dr. Thomas Hamilton ........................................................................... 149 6.5 The Lulejian Report ............................................................................. 157 Appendix A Units and Measures ........................................................................... 159 Appendix B Acronyms and Conversions ............................................................. 160 List of Acronyms ............................................................................................... 160 Conversion Table ............................................................................................. 162 References ................................................................................................................. 164 Distribution List ......................................................................................................... 181 Table of Contents vi January 2013 CASTLE BRAVO: Fifty Years of Legend and Lore List of Figures Figure 0–1. Utirik Island village seen from a raft bringing radiation safety monitors to shore, 3 March 1954 ............................................................................................. iii Figure 0–2. The Republic of the Marshall Islands. (US Government, 1989) ................................ xi Figure 1-1. Radioactive fallout from the CASTLE BRAVO nuclear detonation ........................... 1 Figure 1-2. General Clarkson (left) visits with Kabdo of Utirik and John, the magistrate of Rongelap. Admiral Clarke, commander of Naval Station Kwajalein, is on the right. Naval Station Kwajalein, 5 March 1954. .............................................. 3 Figure 1-3. Rongelap Atoll photographed from the International Space Station ........................... 5 Figure 1-4. Windswept trees on Majuro Island .............................................................................. 6 Figure 1-5. The effects of preinvasion bombardment on Kwajalein ............................................ 11 Figure 1-6. Emaciated Japanese Naval personnel......................................................................... 13 Figure 1-7. CROSSROADS BAKER nuclear test ........................................................................ 18 Figure 1-8. Eniwetok Atoll ........................................................................................................... 22 Figure 1-9. Cartoon from More Minus than Plus ......................................................................... 24 Figure 1-10. The IVY MIKE device ............................................................................................. 28 Figure 1-11. Bikini Atoll with the locations of the five nuclear tests conducted during Operation CASTLE. BRAVO was “Shot 1.” .......................................................... 29 Figure 1-12. BRAVO shot site showing the causeway with vacuum line-of-sight pipes connected to the shot cab ......................................................................................... 31 Figure 1-13. Alvin C. Graves, scientific director, JTF-7 .............................................................. 33 Figure 1-14. Los Alamos scientists Harold Agnew, Marshall Holloway, and Wallace Leland. Photograph taken at Parry Island,10 February, 1954. ................................ 33 Figure 1-15. Construction of the vacuum line-of-sight pipes for the weapon diagnostic experiments, top view. Arrival of the BRAVO device on the shot islet on 20 February 1954, bottom. ....................................................................................... 34 Figure 1-16.The BRAVO device installed in the shot cab ........................................................... 35 Figure 1-17. The BRAVO crater as seen from space ................................................................... 35 Figure 2-1. Launching a weather balloon ..................................................................................... 36 Figure 2-2. Command briefing in the weather and radiation briefing room aboard the USS Estes ................................................................................................................. 39 Figure 2-3. Task Force Command ship USS Estes [CG-12], 16 February 1954 .......................... 40 Figure 2-4. Hodograph of the winds-aloft for the BRAVO event ................................................ 41 Figure 2-5. The IVY KING detonation......................................................................................... 44 Figure 2-6. Cartoon from More Minus than Plus ......................................................................... 47 Figure 3-1. CASTLE BRAVO detonation .................................................................................... 48 Figure 3-2. BRAVO event, 3.5 seconds after detonation ............................................................. 53 Figure 3-3. BRAVO event, 62 seconds after detonation .............................................................. 54 Figure 3-4. BRAVO event, 16 minutes after detonation .............................................................. 55 Figure 3-5. RADEX plot for the BRAVO event ........................................................................... 57 Figure 3-6. Reconstruction of the BRAVO fallout pattern made several days after the detonation................................................................................................................. 58 Figure 3-7. NRDL reconstruction of the BRAVO primary fallout pattern................................... 61 Figure 3-8. ARDC reconstruction of the BRAVO primary fallout pattern .................................. 62 List of Figures vii January 2013 CASTLE BRAVO: Fifty Years of Legend and Lore Figure 3-9. RAND Corporation reconstruction of the BRAVO primary fallout pattern .............. 63 Figure 3-10. CASTLE YANKEE primary fallout pattern ............................................................ 64 Figure 3-11. The BUSTER CHARLIE detonation was a 14 kt airdrop at the NPG on 30 October 1951....................................................................................................... 65 Figure 3-12. Preshot scaling of the JANGLE surface fallout data to the CASTLE BRAVO event .......................................................................................................... 67 Figure 3-13. Postshot scaling of the JANGLE surface fallout data to the CASTLE BRAVO event. Reproduced from Steton et al. (1956). ........................................... 69 Figure 3-14. Forecast air particle trajectories issued 9 hours before the BRAVO event .............. 71 Figure 3-15. Actual air particle trajectories issued 9 hours after detonation ................................ 72 Figure 3-16. BRAVO event, 30 minutes after detonation. ........................................................... 74 Figure 3-17. Wind-time summary charts for mid-February through March 1954 ....................... 75 Figure 3-18. William Ogle, commander, TG7.1, scientific group ................................................ 78 Figure 3-19. The CASTLE UNION nuclear cloud ....................................................................... 79 Figure 3-20. The BRAVO shot islet ............................................................................................. 81 Figure 3-21. Operation CASTLE device barge ............................................................................ 82 Figure 3-22. The UNION device barge ........................................................................................ 83 Figure 3-23. The NECTAR shot barge ......................................................................................... 83 Figure 3-24. The YANKEE device in a barge cab ....................................................................... 84 Figure 3-25. The Consolidated Vultee B-36D heavy bombing aircraft was the largest ever in service .......................................................................................................... 85 Figure 3-26. Task force scientists Don Ehler (Los Alamos) and Herbert York (Livermore) in General Clarkson’s briefing room with models of the devices to be tested, 17 March 1954 ........................................................................ 87 Figure 4-1. The radiation survey party comes ashore on Rongelap Island, 20 April 1954 .......... 89 Figure 4-2. The task force WB-29 WILSON cloud tracker, Eniwetok, 12 February 1954 .......... 91 Figure 4-3. HASL Navy P2V Neptune fallout monitor, Fred Island (Eniwetok), 12 February 1954 ..................................................................................................... 92 Figure 4-4. The radiation survey party from the USS Nicholas (DDE-449) lands at Rongelap Island. Note anticontamination booties worn over shoes. 9 March 1954. .......................................................................................................... 94 Figure 4-5. Mr. Strope taking sand samples for radiation tests, Sifo Island, 10 March 1954 ......................................................................................................... 94 Figure 4-6. First Lt. W. J. Larson gathering soil samples, Utirik Island village, 3 March 1954 ........................................................................................................... 95 Figure 4-7. The levels of residual soil contamination throughout the Marshall Islands were measured during the Nationwide Radiological Study................................... 101 Figure 4-8. Rongelap village radiation survey, 9 March 1954. Note anticontamination booties worn over shoes. ........................................................................................ 104 Figure 5-1. Utirik Island village, 3 March 1954 ......................................................................... 105 Figure 5-2. Rongelap village school, 10 March 1954 ................................................................. 106 Figure 5-3. Principal task force HF radio circuits....................................................................... 108 Figure 5-4. Rongelap and surrounding atolls .............................................................................. 110 Figure 5-5. Men of the Rongerik service detachment, Naval Station Kwajalein, 20 March 1954 ....................................................................................................... 113 Figure 5-6. The USS Philip (DDE-498) ..................................................................................... 116 List of Figures viii January 2013 CASTLE BRAVO: Fifty Years of Legend and Lore Figure 5-7. John, the magistrate of Rongelap, Naval Station Kwajalein, 20 March 1954 ......... 116 Figure 5-8. Jabwe, the Rongelap health practitioner, assists Nurse Lt. M. Smith and Dr. Lt. J. S. Thompson, during a medical examination on Kwajalein, 11 March 1954 ....................................................................................................... 118 Figure 5-9. The shadow of the Navy PBM seaplane crossing Utirik Atoll, 3 March 1954 ........ 121 Figure 5-10. USS Renshaw (DDE-499), 15 February 1954 ....................................................... 122 Figure 5-11. Utirik Island radiation survey................................................................................. 123 Figure 5-12. Awaiting evacuation, Utirik village, 3 March 1954 ............................................... 124 Figure 5-13. Decontamination procedures performed at Naval Station Kwajalein .................... 125 Figure 5-14. Individual research programs were uniquely identified by number ....................... 131 Figure 5-15. A typical house in the main part of Rongelap village, 8 March 1954 ................... 137 Figure 5-16. A Rongelap village scene, 9 March 1954 .............................................................. 137 Figure 5-17. A cooking area at Sifo Island, 10 March 1954 ....................................................... 138 Figure 5-18. Checking radiation of drying copra in tent area, Sifo Island, 10 March 1954 ....................................................................................................... 138 Figure 5-19. Water catchment cistern, Rongelap village, 20 April 1954 ................................... 139 Figure 5-20. General Clarkson visits with island evacuees, Naval Station Kwajalein, 5 March 1954 ......................................................................................................... 139 Figure 5-21. Evacuated children at Kwajalein, 20 March 1954 ................................................. 140 Figure 6-1. Mr. Jack Tobin, the Marshall district anthropologist, visits with John, the magistrate of Rongelap, and Komboj of Utirik, Kwajalein Navy Base, 11 March 1954 ....................................................................................................... 141 Figure 6-2. Prevalence of manually palpable thyroid nodules in relation to BRAVO fallout radiation exposures ..................................................................................... 151 Figure 6-3. Prevalence of ultrasonically detected thyroid nodules in relation to BRAVO fallout radiation exposures ..................................................................................... 153 Figure 6-4. Prevalence of ultrasonically detected thyroid nodules in relation to BRAVO fallout radiation exposures ..................................................................................... 154 Figure 6-5. Native outrigger paddling toward the beach, Utirik Island lagoon, 3 March 1954 ......................................................................................................... 180 List of Tables Table 4-1. Operation CASTLE cumulative doses by event and location (exposures in milli-Roentgen) ................................................................................. 97 List of Tables ix January 2013 CASTLE BRAVO: Fifty Years of Legend and Lore Acknowledgments Special acknowledgement is due to Roger Meade, the Los Alamos National Laboratory (LANL) archivist, Jack Carter, of LANL classified reports library, and Martha DeMarr and John Harney, Jr., of the Department of Energy Coordination and Information Center (DOE/CIC) (now the DOE Nuclear Testing Archive [NTA]) in Las Vegas, for their help and assistance. Without the many years of effort they and their colleagues spent in collecting, preserving, and cataloging the many records in these comprehensive collections, it would have been quite impossible to document so thoroughly activities of 50 years past. The prompt response of Mike Pankratz, Los Alamos Office of Declassification, and Herb Hoppe, TASC Defense Threat Reduction Agency (DTRA) J9 A&AS, in reviewing documents and preparing declassification actions was of special help during the 2004 document review. Changes in classification guidance allowed several previously unavailable records to be released, and better quality copies of many other formally classified documents available through the DOE/NTA or the National Technical Information Center (NTIC) (now the National Technical Information Service) also were reviewed and released. Thanks must go to those who kindly reviewed and commented on various drafts of this manuscript. These include Operation CASTLE alumni Duane Sewell (Deputy Commander, TG7.1), Bob Campbell (TG7.1 J-6), Carl Lyon (TG7.1 J-3), Garry Higgins (TG7.1 TU-12), and Roger Ray (TG7.1 J-3). Hal Plank (TG7.1 TU-1) and Phil Krey (HASL) also provided helpful comments and suggestions. Los Alamos staff members Don Westervelt and Jim Ogle, and DOE Pacific Area Support Office Program Manager Harry Brown also must be acknowledged for their helpful comments on the various drafts. Special thanks are extended to the family of Bill Ogle (Commander, TG7.1) for allowing access to personal family records, and to Dr. Payne Harris for providing copies of his personal diaries and daybooks. We also appreciate the comments and insight provided by Dr. Yuri Dubusov, Khlopin Radium Institute, Saint Petersburg, Russia. Finally, thanks to the Defense Threat Reduction Information Analysis Center staff for providing many of the photographs and for final technical editing support. The location of the Marshall Islands is illustrated in Figure 0–2. Acknowledgments x