Sample No.
Atoll
Island
Date
ur /Hr
1
2
Rongelap
Rongelap
8 Mar
300
3
Rongelap
8 Mar
350
4
Rongelap
8 Mar
400
5
Utirik
Rongelap (central cistern)
Rongelap (North part of
village)
;
Rongelap (Northernmost ~
cistern)
Rongelap (Southernmost
cistern)
8 Mar
220
6
Utirik
7
Rongerik
Utirik (cistern near church)
Utirik (cistern at south of
village)
9 Mar
9 Mar
Eniwetak (Distillation water) 10 Mar
L0
LO
24,0
In addition to the above, a sample of foilage was taken at the wind-
ward side of Bikar Island,
at this point,
8.
The radiation field was 180 or/hr on 9 tarch 195);
Conclusions and Recommendations
ae The radiological survey proved that a large yicld surface detor::.
tion can produce extremely serious radiological contamination over a distance.
more than 120 miles downwind and important contamination about 250 miles cow:
wind.
b. The center of the contamination pattern from the BRAVO Shot lic:
somewhat north of Rongelap and Rongerik jtolls and probably not far froma lL:
between Bikini and Bikar,
Ce Although the fall-out was serious om Rongelap Island located at
the extreme southeast tip of the atoll, the contamination wes about ten times
greater at the north side of the atoll, twenty miles away.
d. The cmtamination decroased by a factor of about cight over the
downwind distance of 50 miles between Rongelap and Rongerik.
e, Standard military field housing provides a sigqificant degree of
protection to personnel inside,
f.
The AN/PDR-39 proved to be a very satisfactory instrument for
ficld survey work under rigorous environmental conditions.
g. A single DDE with two (2) whale boats is not a completely satis—
factory method of conducting a brosd radiological survey of the type jut
completed, Future surveys should consider using vessels capable of entering
more of the atolls and of handling a helicopter and several smil boats.
COPIED/DOE
LANL Ro
6 Incls:
1. Fad. Survey Rongelap
2. Rad. Survey Utirik
3. Rad. Survey Bikar
4. Rad. Survey Rongerik
5. Rad. Survey Anginae—age%
6,
/s/ Herbert Scoville
DR. HERBERT SCOVILLE
Technical Director
AFSYP
oe
y
VF