/
“XN
U7”
TASK GROUP 7.4, PROVISIONAL
—
APO 187, c/o Postmaster
San Francisco, California
teoe 37 O
U, April 1954
MEMORANDUM FOR THE RECORD
SUBJECT:
1,
Evacuation of Rongerik After Shot BRAVO, Operation CASTIE
Twenty-four (24) airmen and one (1) Warrant Officer of the
Weather Reporting Element (Provisional), Task Group 7.4 were assigned
to operate a weather station for JIF SEVEN on Rongerik Atoll, Marshall
Islands. In addition this detachment operated a recording radiation
rate meter for the New York Operations Office, AEC, The purpose of the
device was to measure and record any radioactive fall-out which might
occur after an atomic detonation on either Eniwetok or Bikini Atolls
_ during Operation CASTIE,
This radiac station was one of several situated
in the Pacific Ocean area as part of a general fall-out study.
The
‘instrument was capable of detecting a maximum activity of 100 mr/hr.
Above that figure the instrument was inoperable. li M, R. Breslin, JIF
SEVEN was the local representative of the New York Operations Office,
AEC.
2.
Three (3) Army enlisted men assigned to Task Group 7.1 were
stationed on Rongerik to operate an Ionosphere measurement station for
Project 6.6, These personnel shared messing and housing facilities with
the Task Group 7.4 detachment,
3.
0
Shot BRAVO was fired on 1 March 1954 at approximately 0640
2 9
0 &
local time on CHARLIE Island located in the northwest corner of Bikini
Atoll,
Atoll,
-%
The ZERO point was approximately 130 nautical miles from Rongerik
—
> a
4. The following is a chronological sequence of messages and decisions leading up to and through the evacuation of the personnel on
Rongerik Atoll on 2 March 1954:
a. Message No, 1: From Weather Detachment at Rongerik to JIF
SEVEN, 1500, 1 March 1954 — "Attention Mr Breslin, Info Commander, Weather
Reporting Element, Provisional,
GR 12 MIKE over 100 CHARLIE - Over 100."
Above message received AACS Communications Center, Eniwetok
at 1543, 1 March, and delivered to US Army Communications Center, Eniwetok
at 1547 (local time) for transmission to JTF SEVEN,
Commander WREP GR 12" was in the body of the Bs
Test Services Unit, TG 7.4, was not informed
Because the "Info
the Weather Element
ofA!
S