§.
The yield of “BIL.VO was three times the nost probable
predicted value and twice the predicted upper limit,
Consequently, more
radioactive debris was carricd up and diffused over a uch larser erca than
was expected.
HL.VO demonstrat. 4 that the origin of the fallecut pattcrn is
&@ large ares’ up to 25 miles in radius, varying accoriing to the yield.
Uidicoe
active intensitics at specified distances, likewise, varies with the yicld.
&
BaiVO produced high contamination on populate: areas
ismedictely to tho east of the test site which necessitat.d the ovecuation of
groups of Morshall Islands natives and certain U. S. military sersonncl,
Elements of the task force fleet and personnel were involved in early f2ll-out
which necessitated full use of navel atomic countermeasures and retirement
of the fleet to recions more distant from ground sero.
The incidcnts assceiate
ed with this shot resulted primarily from the lack of fall-out information
from previcus shots of comparable yield, the unexpectedly hich yield of Hu.vo
and an average deviation of approximately ten degrees (in *n adverse direction)
between the observed and forecast winis for shot time.
The net result was an
aggrevation of the adverse. conditions ordinarily predictable and acceptable
under operational criteris ani forecasting techniques in existence pricr to
the BRAVO event.
"J. all CaSTLE shots subsequent to BR.VO were detonated
sithoat sisnificant fall-out impact.
This was duo to complete analyses of
the effects of Hu.VO, the application of this inform-tion in the development
of realistic and dopendable fall-out forecasting techniques and the devclop=
ment of better liniting wind pattern criteria within which the fsil-out
pattcrn could safely lic.
8.
°
82 natives of Rongelap toll and 154 artives of
Utirik ware evacuated to Kwajalein .toll as a result of the f-il-out fron