= | =‘ WATER

Samplo No.

Atoll

Island

Date

lr Air

1
2

Rongelap
Rongelap

8 Mar

300

3

Rongelap

8 Mar

350

4

Rongelap

8 Mar

4,00

5
6

Utirik
Utirik

8 Mar
9 Mar

220
40

7

Rongerik

Rongelap (central cistern)
Rongelap (North part of
village)
Rongelap (Northernmost
cistern)
Rongelap (Southernmost
cistern)
Utirik (cistern near church)
Utirik (cistern at south of
village)

9 Mar

Eniwetak (Distillation water) 10 Mar

40

240

In addition to the above, a sample of foilage was taken at the win

ward side of Bikar Island, The radiation ficld was 180 mr/hr on 9 March 19%
at this point,
8.

Conclusiois and Recommendations

ae Tho radiological survey.proved that a large yicld surface -deto.
tion can produce extremely serious radiological ontamination over a distanc
more than 120 miles downwind and important contamination about 250 miles dov.
wind.
b. The center of the contamination pattern from the BRAY Shot lic
somewhat north of Rongelap and Rongerik Atolls and probably not far froma 1
between Bikini and Bikar,
ce

Although the fall-out was serious on Rongelap Island located at

the extreme southeast tip of the atoll, the contamination was about ten tin
greater at the north side of the atoll, twenty miles away.

d. The contamination decreased by a factor of about eight over the
downwind distance of 50 milcs between Rongelap and Rongerik.
e. Standard military field housing provides a significant degree c
protection to personnel inside,

f.

The AN/PDR-39 proved to be a very satisfactory instrument for

ge

A single DDE with two (2) whale boats is not a completely satis

field survey work under rigorous environmental conditims,.

factory method of conducting a broad radiological survey of the type just
completed, Future surveys should consider using vessels capable of entering

more of the atolls and of handling a helicopter and several smil1 boats.
6 Incls:

1. Rad. Survey Rongelap

2, Rad. Survey Utirik

3. Rad. Survey Bikar

4, Rad. Survey Rongerik

5. Rad. Survey Ailinginae

/s/ Herbert Scoville

DR. HERBERT SCOVILLE

Technical Director _..

AFSWP

6. Summary of Rad. Survey@igeteeiaieaian

Select target paragraph3