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RADSAFE NARRATIVE SEQUENCE OF EVENTS
By the morning of B-l day, the wind patterns (forecast and actual)
were favorable but the trend of the observed resultant wind patterns
was toward an unfavorable or marginal condition. No transient shipring
was reported on the Be2 day P2V sweep centered on a significent fare=
cast cloud movement on true bearing of 300° out to 800 miles from @.
The B-l day search by P2V out to 375 miles on a forecast significent
cloud movement on a true bearing of 330° disclosed no transient ship=
ping except the General Patrick, whose course ani speed would take be
outside the hazardous area by spot time, At the midnight briefing, the
forecast offered a less favorable comiition in the lower levels (10-25
thousend feet).
Resultant winds at about 20,000 feet were forecast in
the direction of Rongelap and Rongerik (Figure 1); however, it was con=-
sidered that the speeds and altitudes did not warrant a conclusion that
significant quantities ani levels of debris would be carried out so far.
TARE Site was forecast to be well in the fall-out area and NaN Site to
be in a fairly high intensity area. Since the B-1 day forecasts gave
winds tending significently toward ENE, a decision was mede at the mid-
night briefing to search on B day ahsad of the cloud, i.e., centered on
true bearing af 65° out to 600 NM and to warn ships out of the 450 WM
minigun radius,
.
blems on air or surface routes except surface routes between 275° clock=
wise to 80° out to a radius of 450 RM with possible significant fall-out
in this area. No known shipping was in the forecast fall~out area. The
surface radex was forecast for shot time to shot plus six hours to be
oriented in a narrow sector to the northeast and a wide sector to the
south, with an additional circular radex area around GZ of radius 15 ules
(Figures 1 ani 2). The sector pointing at Rongelap was considered insig~
nificent due to the low altitudes from which fall-out could occur and due
to the very light winds acting on the levels involved.
At the 0430, 1 March briefing, no significant change had been observed in the midnight winmis received, however, a radsafe recommendation
was maje to move the task force ships radially further out from the minie
rum of 30 RM to a cinimum of 50 NU in the SE quadrant. The low level
cloud was forecest to overrun the TARE camp and move on to the east with
adrong possibility of overrunning NAN. The resultant winds pointing at
Rongerik and Ricngelap were light and were not forecast to transport signi“{sart detris to these etolls.
bt 0645 the BRAVO detonation was accomplished without hacard to
task force personnel.
The bunker firing party reported in safe, but by
O715 the radiation levels ware reported rising at the bunker.
levels contimed to rise to about 25 r/nr.
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These
The firing party was con
wauhivted DATA
RESTRICTED DAT.
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The routine H-18 hour advisory to CINCPACFLT indicated no significant fall-out forecast for poplated Marshall Islands, ani no safety pro~