surveyed were Irene, Janet, Sally, Tilda, Ursula, and Yvonne.
Exposure rate measurements showed
that Yvonne had the highest reading of the islands visited. The survey report stated that the
contaminated metal scrap on Janet probably constituted the major radiological hazard on that
island. A tabulated summary of radiological conditions indicates that the highest exposure rates on
Yvonne were in the order of 1 mR/h at 1 meter while the highest on Janet was one-tenth as high.
Exposure rates on Irene were twice those on Janet, while on Sally the readings averaged 15 uR/h.
Alpha contamination was observed only on Yvonnein the vicinity of the Fig/Quince GZ. (Costa and
Lynch, 1971.)
The original Air Force plan for the PACE programs called for high explosives detonations to be
conducted on Janet and Yvonne. Resulting craters were to remain for undetermined future study. In
response to requests by the Enewetak Marine Biological Laboratory of the University of Hawaii, the
AEC, and EPA, islands other than Janet were considered for PACE test sites, as Janet was a
potentially valuable land asset. Island Sally was finally selected instead of Janet, based partially on
the results of the radiological reconnaissance.
Program of September 1971, Based upon findings of the July 1971 reconnaissance survey, a
comprehensive radiological program wasinitiated for PACE on 27 September 1971. AEC and EPA
personnel assisted in the establishment of the program conducted by the Air Foree which included
surface surveys and soil and water sampling of the islands of interest. Extensive radiological surveys
were conducted on Irene, Sally, Tilda, Ursula, and Yvonne with the readings confirming those
recorded in July 1971. An alpha contamination area on Yvonne was defined in detail and fencedoff.
Two sites on Sally known to contain plutonium contamination were surveyed for leakage. No leakage
was found but the areas were fenced off anyway.* (PACE, 1971.)
Survey of May 1972. When it became apparent, early in 1972, that Ambassador Williams planned to
commit the United States to relinquish control of Enewetak to the Trust Territory administration,
NV recommended and AEC/HQ approved an extension of the Spring 1972 survey of Bikini to include
Enewetak.
In the Enewetak portion of the survey, an attempt was made to cover as many islands as possible,
with 18 of the 43 islands actually visited, thus bringing to 21 the numberof islands for which recent
data had been collected. The results of this survey showed the same pattern of atoll-wide
contamination suggested by the 1971 survey, namely, that the northern islands contained
significantly high levels of contamination while the southern islands had low levels of radiation.
Data from the survey were used to guide the planning and execution of the much larger survey begun
in October 1972.
Survey of 1972-73. Extensive planning preceded the start of the Enewetak Atoll pre-cleanup
radiological survey, authorized 7 September 1972, which had the following specifie objectives:
1.
To locate and identify contaminated and activated debris.
2.
To locate and evaluate any significant radiological hazards which could complicate
3.
To identify sources of direct radiation and food chain-to-man paths having radiological
implications.
eleanup activities.
The Nevada Operations Office distributed a planning directive on 4 October 1972 which outlined the
purpose, objectives, and plan for the 1972 Enewetak Atoll Radiological Survey, established
authorities,
responsibilities,
and procedures for its execution,
and set
definition, coordination, and authorization for funding. (NVO-12], 1972.)
forth program
policy,
*In 1957, the Kickapoo and Yuma tower bases were each covered with a 3-inch layer of clean
concrete and a bronze plaque attached which stated, "This three inch thick slab covers plutonium
contaminated concrete debris." These two remains were erroneously identified as "crypts" by PACE
personnel and the misnomerpersisted into the cleanupproject.
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