Field work for this survey was conducted between October 1972 and February 1973.
Laboratory
analysis of the samples collected continued into July 1973 and the final report, about 2,200 pages in
three volumes, was published in October 1973 and distributed early in 1974 with the title "Enewetak
Radiological Survey." (NVO-140, 1973.) Actual cleanup at Enewetak during 1977-79 relied heavily
on the large quantity of data and maps found in NVO-140 for guidance in planning the overall field
effort and the day-to-day details of project operation.
No attempt will be made here to summarize the results of NVO-140.
Instead, the three-page
Abstract has been reproduced and is included as Figure 2-1 to illustrate the primary thrust of the
project. In accordance with objective 3 stated above, the Abstract deals primarily with the data
required for judgments as to whether or not all or any part of the atoll can be safely reinhabited.
2.1.5 AEC Task Group Report
On 7 September 1972, the AEC agreed to provide radiological criteria for cleanup and rehabilitation
of Enewetak Atoll to DOD and to the Department of the Interior (DOJ). AEC also agreed to conduct
a comprehensive radiological survey, as discussed in Section 2.1.4. In July 1973, a Task Group was
established to review the survey findings and to prepare cleanup and rehabilitation recommendations
for consideration by the Commission. Two members of the Task Group were from the AEC, and two
were from Lawrence Livermore Laboratory (LLL). The Task Group utilized seven advisors and
consultants, six of whom were from various divisions within the AEC. Representatives from DNA,
EPA, and DOI attended Task Group meetings.
The job of the Task Group was to recommend for consideration by the Commission, radiological
criteria for cleanup and rehabilitation of Enewetak Atoll and to recommend those remedial measures
and actions needed to reduce exposures of the Enewetak people to levels within these criteria; the
underlying objective was to keep exposures as low as practicable. At the time the Task Group was
established, there were no criteria applicable to remedial action for soil contaminated with
plutonium. However, an interim standard was proposed (Healy, 1974) during the period the Task
Group was in deliberation, ano this proposal was utilized in formulating final recommendations. The
Task Group, advisors, and consultants reviewed the AEC Radiological Survey results (NVO~140);
then-current information on the life style, diet, and rehabilitation preferences of the Enewetak
people; applicable radiation protection guidance established by various national and international
radiation standards-setting bodies; and then-current laws and regulations pertaining to disposal of
radioactive waste materials. In its final report the Task Group notes that "...experts are not in
agreement as to the critical organ for inhaled plutonium, whether to use an average dose for this
organ, or the model to be used to predict dose." (Task Group, 1974, App. IIL)
The objective for cleanup at Enewetak was stated by the Task Group in the following passage:
"For contaminated soil, other than plutonium, the Task Group has not included
removal of such soil in its recommendations and therefore there would be no
requirement to select a method of disposal. If such disposal were required, the
objective would be to assure that there would be no pathway for any exposure of the
Enewetak people to this radioactivity and a minimal follow-up requirement to insure
that this situation continues after disposal.
"The Task Group view is that because of its extremely long half-life, disposal of
plutonium in the form of contaminated soil and scrap is a problem of greater
magnitude than for fission products and induced activity. In its deliberations, the
Task Group has assumed that the disposition of such material will be such that there
is no potential for exposure of the residents of the Atoll once cleanup has been
completed. This is then the objective for cleanup." (Task Group, 1974, p.15.)
Recommendations developed were considered by the Task Group most appropriate for the U.S.
Government to translate into actions to provide a radiologically acceptable environment for the
Enewetak people. The complete text of the recommendations is reproduced in Figure 2-2 for
reference. The final report of the Task Group was released in June 1974, whereupon the group was
disbanded.
39