1 May 2009 -- Volume 1, Number 2 MARSHALL ISLANDS RADIOLOGICAL SURVEILLANCE GROUP BIKINI , ENEWETAK , RONGELAP , UTROK MARSHALL ISLANDS MONITOR A note from the editor Inside this issue The cover photo features the A note from the editor Enewetak Radiological Laboratory —a whole-body counting facility Feature article: used to determine doses of Is there any truth behind the radiation delivered to island residents as a consequence of the secret Bravo map? nuclear test program that took place in the northern Marshall Renewing hopes for full resettlement of Islands from 1946 to 1958. Bikini, Enewetak and Rongelap In addition to Enewetak, Lawrence Whole-body counting technicians receive training Livermore National Laboratory in Livermore, California helped atoll governments establish whole-body counting The DOE releases fi eld survey report on Runit Dome facilities on Rongelap and Did you know? Majuro islands with the total number of program volunteers Upcoming Events engaged across the three facilities now exceeding 3,000 people. Marshallese technicians are primarily responsible for the day-to-day operations of these whole-body counting facilities while scientists from the Lawrence Livermore Laboratory provide training, system maintenance, facility upkeep, data quality assurance, and reporting. Terry Hamilton, PhD Editor in Chief Feature Article Is there any truth behind the secret Bravo map? In a March 13, 2009, issue of Marshall Islands vaporize several hundred thousand tons of post detonation (H+1 hour). Consequently, Journal, the authors discuss a map of the soil and associated materials. The amount of there is a fundamental diff erence between infi nite dose contours (in Roentgens) from debris sucked into the atmosphere depends these contour maps that has contributed to the initial U.S. Air Force aerial radiation on the nature and altitude of the test. High the confusion. Also, dose estimates to infi nite survey conducted in the fi rst few hours after temperature vaporization and condensation time should not be confused with actual the Bravo detonation on March 1, 1954. processes produce diff erent types and sizes doses delivered to Marshallese exposed to Reference was made to a newly declassifi ed of radioactive particles that deposit as local radioactive debris from the Bravo test and document that has actually been available for or regional fallout or may be carried into later evacuated. Another radiation dose many years. Commentary was given on the the upper atmosphere and spread around unit that will be used for some comparisons magnitude and the geographical coverage the globe. Forecasting the intensity and is the “Rem” that for the purpose of this of the Air Force dose contours relative to depositional velocity of radioactive debris discussion can be considered equivalent to updated contour maps that appear in most of from large nuclear blasts is a very complex the Roentgen. The other units used in this the scientifi c literature. The updated contour issue. It depends of the size of test, the type discussion will be the milliR (mR) and millirem maps were generated after more detailed and quantity of materials consumed in the (mrem) that are each 1000 times less than the post-shot information became available after blast, localized wind patterns as well as upper rem and the R, respectively. the Bravo event. The authors assert that: atmospheric conditions. It is for this reason The Air Force map shown in the Marshall “What is signifi cant about this Air Force fallout that initial high altitude aerial surveys were Islands Journal was generated in the fi rst contour map, prepared shortly after the 1954 conducted immediately after major test hours after the Bravo detonation. It was based Bravo test, is that it shows a much wider events to confi rm the general direction and on the fi rst aircraft fl yover of the potentially fallout contamination than an offi cial fallout intensity of the radiation fi eld, and then to contaminated area once it was determined map used in numerous reports about Bravo use ground-truth measurements (radiation that the bulk of the debris cloud moved in published since 1954.” detectors, gummed paper, or other) to more an easterly direction. The purpose of the accurately defi ne the fallout pattern on the fl ight was to get a “general” perspective on The remainder of this article provides a ground. This is exactly the pattern of events the debris cloud direction, and provide initial discussion about why the various aerial that followed the Bravo test. estimates of radiation doses and the area contour maps are really quite similar and Characteristics of fallout from encompassed by the deposition. Such actions provides data that show that the extent of the the Bravo test formed part of a regulated military response Bravo fallout was well documented in the fi rst to all major nuclear test denotations. fi ve days after the Bravo detonation. All these Immediate Aerial Data The Air Force developed a later version of data have been available for many years. When viewing the diff erent versions of the the dose contour map after they had more contour maps discussed below it is important Background time to evaluate data obtained during the to understand that diff erent units are used Radioactive debris is an inherent initial fl yover and ground truth data became to denote levels of radiation exposure and characteristic of all nuclear detonations. It available (AFSWP-895). This graph is given in dose. Very careful consideration should originates from the fi ssion of the nuclear mR per hour (as are most of the other contour be given to the radiation units because fuel and from interactions of the explosion maps), rather than infi nite dose as was the otherwise it is very easy to misinterpret with surrounding materials such as soil and case for the original Air Force map. This is the data and, once in the public domain, this version that is more commonly seen (example water. Hundreds of diff erent radioactive can lead to unnecessary public radiation shown in Figure 1) and used in various isotopes are formed during a nuclear hysteria. The Air Force map shown in the publications (AFSWP-895). It has an outside detonation. These radioactive isotopes Marshall Islands Journal gives the radiation contour line of 25 R per hour at H+1 hour (also called radionuclides) are composed data in total “Roentgens (R) of infi nity dose” and of course encompasses very much less of about 35 diff erent elements ranging in whereas the Rand Corporation (Rand), Naval territory than the map in the Marshall Islands half-lives from fractions of a second to 17 Radiological Defense Laboratory (NRDL), and Journal. The map does show a small segment million years. The energy released from a a later version of the Air Force map, report of the 1 R contour line going through Ailuk large near-surface detonation is suffi cient to the radiation levels as R per hour at 1 hour Continued on next page 2 -- Marshall Islands Monitor Continued from previous page so low the contours encompass a very, very NYOO (New York Operations Offi ce, Atomic Secret Bravo map large area. Energy Commission) Kwajalein fl ight “Able” Atoll. The outside dose rate contours on the In addition to the radiation data generated by covered Lae, Wotho, Rongelap, Taongi, Utirik, commonly seen NRDL and Rand maps are 50 the initial Air Force fl yover there was a report Ailuk, Likiep, Ujae, Ailinginae, Rongerik, Bikar, R per hour and 30 R per hour, respectively, from U.S. personnel at Enewetak Atoll on the Taka, and Jemo Atolls. and encompass less territory but do cover night of March 5, 1954, of radiation levels of NYOO Kwajalein fl ight “Baker” covered Namu, the most contaminated atolls in the Marshall 3 to 4 mR per hour at Enewetak and Medren Namorik, Kili, Mili, Majuro, Maleolap, Wotje, Islands. These H+1 hour dose rates are Islands with a reported maximum of 15 mR Aiglinglaplap, Ebon, Jaluit, Arno, Aur, and decaying (declining) rapidly in the fi rst hours, per hour (Castle Series, 1954). Erikub. days, and weeks after the detonation at a rate NYOO Kwajalein fl ight “Charlie” covered Kusai, Additional Gamma data from aircraft inversely proportional to the time “t” after Mokil, Ujlelang, Pingelap, and Ponape. detonation (1/t1.2). fl y-over of atolls and islands (D to D+5 days) NYOO Guam fl ight “Easy” covered Guam, Truk, The NRDL (Steton et al., 1956) and the Rand Losap, Lukunor, Pulap, Namonuito, Kuop, Corporation (Rand, 1955) both published The initial Air Force contour map and the subsequent NRDL and Rand versions of the Namoluk, Satawan, and Guam (a second revised versions of the initial Air Force fl yover time). data that give the direction of the debris cloud direction and estimated radiation NYOO Oahu fl ight “George” covered Kauai, cloud and the radiation levels on the ground. deposition were initially useful to understand Kaula, Necker Gardner Pinn., Laysan, Pearl- These contour maps were supported by the scope of the problem. But much more Hermes reef, Niihau, Nihoa, Fr. Frigate reef, additional radiation data from aerial fl yovers detailed and precise data were generated in Lisianski, and Midway. and ground truth radiation measurements the fi rst 5 days after the Bravo detonation to at many atolls during the fi rst few days after determine the actual radiation levels across NYOO Oahu fl ight “Item“ covered Oahu, deposition, and wind data collected in the the entire Marshall Islands and the Pacifi c Hawaii, Molokai, Lanai, and Maui. region. hours immediately after detonation by planes NYOO Oahu fl ight “Gilbert” covered Baru, and ships. To better defi ne the extent of the Arorae, Onotoa, Aranka, Tarawa, Marakai, All of these maps have been publicly available contamination and get better data in the Nonouti, Nukunau, Tamana, Tabiteuea, for many years.