transuranics introduced from these source terms is associated with
components of the marine environment,
components of the benthic environment,
more extensive investigations, concentrating on measurement of
Because of the high level of deposition the Atoll is now its own
transuranic source term,
Plutonium, for example,
is not permanently
The survey was followed by other
transuranice to better assess the impact of these radionuclides on the
environment and inhabitants of the Atoll and to increase our
fixed with the carbonates and other material with which it was
understanding of the mobilization, reconcentration, and redistribution
originally deposited in the lagoon and reef during nuclear testing.
processes from sources within the environment.
Small amounts of plutonium are now remobilized, resuspended,
This paper contains a summary of data related to the concentrations
assimilated, and transferred continuously within the Atoll environment
of the transuranium elements in components of
by physical, chemical, and biological processes.
environment of the Atoll
More than half of the United States nuclear tests in the Pacifie
were conducted at Fnewetak Atoll.
Surface and tower shots left craters
lapoon.
the benthic and pelagic
Data from the survey re part
(Ne/4),
more recent publications, and unpublished results from this laboratory
will be discussed.
Some published and unpublished data from our studies
and contaminated scrap on land and generated radiouctive debris that was
at Bikini Atoll] will be presented when necessary for comparison with
redistributed to the adjacent reef and lagoon.
Enewe tak data and in the ahsence of Enewetak data,
Megaton tests that left
for the clarificatior
underwater craters and barge shots in the lagoon contributed
of characteristics of transuranic radlonuclide concentration. at the
significantly to the present transuranic inventory.
Atolls.
The impact of nuclear testing and the fate of the residual
Whenever possible,
the Atoll] data will be compared with that
from other marine ecosystems,
tadioactive materials introduced to the aquatic environment at both
Enewetak and Bikini Atolls are the subjects of reports too numerous to
list herein.
However, not until late 1972 when a radiological resurvey
GEOGRAPHY AND ATOLL TEST HISTORY
Enewetak Atoll, with U.S.-assigned and native names and several
of Enewetak Atoll was conducted to gather data for the development of
landmarks including the locations of craters formed by nuclear tests,
cleanup and rehabilitation procedures for the resettlement of the
shown in Fig. 1,
Enewetak people to their homeland did extensive measurements of
this report.
transuranics in the Atoll environment begin.
The information was
is
U.S.-assigned island names will be used throughout
The Atoll consisted of a ring of 42 low islands arranged on a
published in the survey report (Ne73), which contains data on most
roughly elliptical reef, 40.2 x 32.2 km
long-lived residual radionuclides, including plutonium and americium, in
in the northwesterly direction,
(fm54), with the elonpeted axis
Nuclear testing completely destroyed
por acer
_
wre