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Machine-read from the scan, so expect some errors. Lines that couldn’t be read are left out.
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The Atomic Energy Commission agreed to provide radiological criteria for cleanup and r ehabifitation of Enewetak Atoll to the Department of Defense (DOD] and to the Department of the Interior (DOI). A comprehensive survey of the radiological environment of Enewetak was made to serve as a bas~s ents and recommendations. The survey data show that the northern islands have the greater am.ourLt of radio c.ctive contamination and The Director, Division of Operational Szfety, appoi~te~ z T~~’~ l Population close to the Enewct.a?t~ people s~lould be as lo’.v as l The Federal Radiation “ .- used to evaluate expcsure opt:ons. The values shcdd be reduced by 50 percent for individual exposure and 20 percent for gonadal exposure to allow for uncertainties in dose predictions. The guides for cleanup planning become: Whole body and bone marrow O. 25 Rem/yr Gonads 4 Rem in 30 yr
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Cleanup of soil containing Pu can be handled on a case-by-case basis using the following: b. 40 to 400 pCi/gm of soil - corrective action determined on a case-by-case basis considering all radiological For comparison with population dose guidelines, evaluations were made for the following conditions: Dose without cleanup. l Dose reductions obtained by diet modification. l Dose reductions achieved by removal of contaminated soil. plus corrective actions: Plow the village island, and gravel the village area fcr Import pandanus and breadfruit from the southern islands (ALVIN-KEITH) for inhabitants of the riorthern islands to control ingestion of radio nuclides. Import pandanus, breadfruit, coconut and tacca from the Import pandanus, breadfruit, coconut, tacca, and domestic meat from the southern islands’. DISPOSAL OF CONTAMINATED MATERIAL Contaminated material is composed of soil, debris and scrap. - At some places there is Pu including pieces of Pu metal. Contamination is distributed on and below the surface; some is in rad waste burial sites. Fission products and induced radioactivity found on such scrap and. . debris, particularly scrap metal, should be made unavailable to - the returning people. Possible approaches are:
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Disposal in water-filled and underwater craters. Land burial where the radiation level of the scrap is not significantly above that on land. Disposal in deep water. Pu excepted, the Task Group has not made recommendations for removal of contaminated soil. I?or any disposal there should be no pathway to people; periodic followmp surveys are necessary. Disposal ..of Pu in any form is a greater problem, and disposal must protect against exposure for the future. OBSERVATIONS AND CONC LVSIOISS The consensus of the Task Group reflects consideration of a range of options and the benefits of reviews and comments. Choice of the method which will optimize reduction of exposures could be effective ‘but is not recommended. Alt’nougi, engi ficericg these actions can otherwise adversely affect the errv=ironrne::t ani acceptable level oi cooperation is expected so tkat they may use lar,2 / where the radiation envirfiriment is or can be made acceptable. Return of people to live on the southern islands, ALVIN’ through KEITH, is expected to result in radiation doses within the recommended ! criteria. JANET (Enjebi), which the people desire for a residence island is a special case of the category of islands having radiationII1 and radioactivity levels which preclude liting and agriculture. Steps 1 - to make this island completely or partially available in the near term are important from the social as well as scientific viewpoint. Predicted radiation doses associated with the Task Group recommenclatiol that people live only on the southern islands, ALVIhT through KEITH, are given in the following table. The Bikini Atoll estimates and typical natural background levels in the U. S. are given for comparison.
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PREDICTED RADIATION DOSE IN REM WITH ADOPTION OF TASK Maximum Annual Dos e:’ Predicted Radiation Dose for Bikini Atoll ~ *See Option III, Table 11, of the Task Group report. Dose includes contribution from natural background, about O. 03 Rem/yr, and O. 90 **The dose to bone marrow is about one-third the dose to bone. ‘:’$f$~Presented in “Additions to Radiological Report on Bikini Atoll, . P. F. Gustafson, Division of Biology and Medicine, ” May 1968. Estimates do not include contribution from natural background.
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The Task Group reached the following conclusions: - Observing precautions, the people may safely return after certain actions are taken. Exposures will be somewhat above current levels in the U. S. , but the small risk seems permissible in relation to the desire of the people to return. assure exposures that till be as low as practicable: j , ~v-”,. ,..,- Villages and residences to be located on ELMER, YR~D, DAVID, or other southern islands (A LVIiQ-KZITH). Travel and visits may be unrestricted to all islands except YVOI$NIZO When Pu contamination on YVONNZ is removed, the restriction of travel to that island may be Coconut excepted, growth of animal and ve~etable subsistence crops to be limited to southern islands AL1’13~-l<EIT1-1. Subsistence and commercial coconut may be giowi~ withaut remedial measures except Gn ALICE, BELLE, CLAR.A-, Fishing permittkd anywhere. Wild birds and eggs may be collected anywhere. Coconut crabs may be collected only on the southern islands Wells to provide lens water for human consumption or for agriculti-ral use to be drilled only on the southern islands (ALVIN-KEITH). Water from any well to be assayed for bacterial, salinity, and radioactivity content before approved Enjebi (JANET) is a special case, and the people have a strong desire to live there. Three ground zeroes were on Enjebi and high yield events were fired nearby, with the result that this was the most heavily contaminated of the larger islands. The Task Group has been unable to determine a reliable, feasible way to bring exposures within the acceptable criteria and permit
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resettlement of Enjebi on the same schedule as southern islands. The island can be resettled sometime in the future when radionuclide ingestion is no longer a problem. To develop the facts, test plantings with and without soil remowl may be made. Construction and agriculture would be deferred until produce from test plantings showed acceptably low levels of radioactivity. Test plantings without soil removal would have least adverse impact on the island environment. Concurrent with the Enjebi work, radioactivity levels should be measured in coconut and other food crops grown on PEARL, CLARA, ALICE, and BELLE. Produce from YVON-N’E sho.~d be included after removal of plutonium contamination. All radioactive scrap metal and contaminated debris now or later identified should be removed. This includes three locations on SALLY and one on ELMER where buried contaminated ciebyis Only general recommendations for cleanup of I% on. Y1’OXIXS can be presented at ‘this time. An accu-ate pict-~re of this contamination should develop as the ciecontami, natiac procec2s The area observed to have small pieces of plutonium and the highest soil concentrations is about 30V0 of the island. A background for plans for the recovery of Pu will require: Assembly of a team of experts to interpret field radiation and radioactivity measurements, advise on cleanup actions and provide necessary health physics support. A Public Health Service group, now part of EPA, provided radiological assistance for cleanup of Bikini Atoll. Similar support should be sought from EPA for Enewetak. Decontamination of YVO~E is seen as an iterative process. This amounts to a search for and removal of the higher plutonium levels in soil.
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c. The objectives of the cleanup are two: (1) Recovery of the pieces of plutonium that have been observed on or near the island surface. (2) Recovery of plutonium contaminated soil. . d. Recovery of lutoniurn in soil at concentrations greater than 400 pCi/g 23?, 240~ at any depth these levels are found. Also, ,recovery of contaminated soil sufficient to reduce surface levels to a value well below 40 pCi/g 23% 24@u. After soil removal, all areas should be resurveyed to ensure Plutonium contaminated soil on IRENE should be handled as on YVONNE. Pieces of Pu metal are not e~ected to be found. Test plantings of food crops may be conducted on each of the “no crops’] islands as designated by the Enewetak people. As edible parts of these plants become available, concentrations of significant radionuclides should be measzwed and compared with the radiological survey predictions. Tnese stuciies will intiicate timee at which planting of subsistence and commercial crops cah be safely res’u.med. Lens water sampling and analysis should be conducted, samples to be taken over a period of at least 12 calendar months. Bactgrial Radioactivity information wtll contribute to an under smrldj-ng of processes operating -- or which can be made to operate - to reduce half-life on the northern islands, especiaUy JANET. A comprehensive air sampling program should be conducted over a period of 12 consecutive months under conditions closely approximating human habitation and expected soil disturbance to provide information on radioactivity levels in air. This program could be conducted coincident with and support cleanup. Base-line surveys of body burdens and nrine content of 137CS and 9°Sr should be made for the Enewetak people prior to return to Enewetak Atoll, and periodically thereafter. Resurveys of the environmental radiation and radioactivity should be made in the first year of return and repeated, for example,
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every other year. ...I Methods of disposal of plutonium contaminated soil and scrap will have to be decided. Pending a decision, it is recommended that cleanup should accomplish the recovery of plutonium contaminated soil and scrap with storage” on YVOhTNE. U disposal is deferred for further .+miy, such study should be initiated The cleanup, with particular attention to removal and disposal of contamir~ted” scrap, debris, and soil, should be documexltcd in detail in a final report by those responsible in t>.e fi-ckl, of Bikini Atoll. No objection should b e made to cmploymeni of Enewetak people during cleanup.