2.2.8 USS ESTES (AGC-12)
At the time of Shot BRAVO, the ESTES was operating in its assigned area eastsoutheast of GZ, somewhat further north than the BAIROKO, PHILIP, and CURTISS,
the three other ships that received early fallout from the BRAVO cloud. Heavy fallout
began on the ESTES shortly after 0800 hours and Condition PURPLE II (Atomic Attack
imminent, one half of crew at battle stations) was set at 0830 hours (Reference 8).
The washdown system was probably turned on at this time and remained on until
approximately 1130 hours, which madeit difficult to obtain reliable intensity measurements (recorded intensities for 0900, 1000, and [100 hours are estimated intensities).
A survey at 1125 hours indicated that conditions were worsening since Condition
PURPLE III (Atomic Attack imminent, one third of crew at battle stations) was set at
this time.
By noon, topside intensities had leveled off at approximately 100 mR/hr
(Reference {0).
more fallout.
At 1400 hours, they began to increase again as the ship encountered
Topside intensities increased to 140 mR/hr at 1600 hours before they
leveled off at 120 mR/hr for the next twelve hours.
At approximately 1800 hours, the
ESTES was directed to proceed to Enewetak Atoll.
While enroute, the washdown
system was activated intermittently but did not prove to be very effective in removing
the fallout particles from the topside surfaces.
Upon arriving at Enewetak at
approximately 0800 hours on 2 March (H+25), decontamination with fire hoses was
probably undertaken for the remainder of the day.
This is evidenced by the steep
decay rate in Figure 2-17 between H+25 and H+35. After departing Enewetak at 1900
hours (H+36), it appears that natural radioactive decay was primarily responsible for
reducing the topside intensities.
Following Shot ROMEO on 27 March, the ESTES reentered Bikini Lagoon at
approximately 1300 hours.
With the exception of a two-hour sortie to sea on 28
March, it remained in the lagoon through 5 April.
During the night of 28-29 March,
the ESTES encountered fallout similar to that experienced on the other ships anchored
in the lagoon.
Average topside intensities reached a maximum of 12 mR/hr, but it
appears that measures to reduce the contamination were not required.
Figure 2-18
depicts the topside intensities on the ESTES resulting from Shot ROMEO fallout. No
other fallout was encountered by the ESTES during Operation CASTLE.
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