man anchorage at H+a@hr. Faye a:eherage was cleer of contatiinates whersos Breird anchorage shoved traces of cuter. satic.. at H+4 hr.
ae
The

Seratar was materially different from that of: _jin that radiation

levels within the crater were dependent on “shine” from the lip of the crater and surrounding

“sand dunes.”

(d);
;
DA daniage aid radintion survey was conductedoni
Day
(Table 4.4). This survey covered th. eastern and northern islands of the atoll and was conclusive enough to limit reentry to Enyu, Bikini, and Airusiiji on the first day. The survey on
__ c+ day indicated that recontamination was limited to the Yurocni-Aommen and
the Bikini- Enyu sequence of islands. No material secondary fall-out was encountered at Bikini
as a result of this detonation.
Table 4.3-—

‘RADIATION SUMMARY IN ROnNTGENS PER HOUR

Extrapolated
H-4hr

Island
Enyu
Bikini*
Aomoen*

0.03
5.0
20.0

Romurikku*

10.0

Uorikku*

5.0

Yurochi*

Namu*
Bokoby aadaa*
Quruka2en*

eens ee
+1 day
0..03
0.67
2.5
,

3.2

Arriikan*

Eniirikku*
Eninman
Airukiiji
Crater

210.0
0.02
5000

*Contaminated by
tReading at 100 ft.
TReading at 200 ft.

‘

“ackground for

0.03
0.07
1.6
0,80

0.50

0.60

0.47

0.60

‘

0,03
0.10
0.35

1.6

30.0

0.50

+7 days

1.0

1.0

250
600
0.60

_

-

0.45

0.98

16.0
16.9
0.02

15
9.0
0,012

0.07

0.01

0.008

2.4f

1.8
0.02

0.008
0.010

0.02
50j

0.02
60

0.018

shot.
.

Lagoon water was n:aterially contaminat:( with radivactive sediment. Readings of 4.2 r,‘hr
were obtained at an alticade of 500 ft over Groind Zero. This contamination moved to the wes!
and southwest so that small-boat operations cou'd be conducted in the area. Lagoon flushing
through the southwest passage materially increased radiation levels in the vicinity of Ourukaen,
Bokoaetokutoku, and Bokororyuru.
a

(e}

ee

A damage and radiation survey was conducted at H+4 hr onf_ bay (Table

4.5). This survey covered the islands of the atoll and was conclusive enough to limit reentry to

Enyu and Airukiiji on the first day. This survey indicated that recontamination was extensive
throughout the atoll and lagoon both to the east and west. No significant secondary fall-out was
encountered at Bikini as a result of this detonation.
Lagoon water was heavily contaminated with radioactive sediment. Readings of 1 r/hr
were obtained at 100-ft altitude in the vicinity of zero point on,
_ti day. Floating objects
revealed readings of 1 to 3 r/hr on shot days. Small boats and barges in Bikini-Enyu anchorage

were contaminated to a moderate degree (1-6 r/hr). Lagoon flushing through the southwest
passage materially increased radiation levels in the Eniirikku-Bokororyuru area.

~

),
‘.

A damage and radiation survey was conducted at approximately H+4 hr on
(Table 4.6). This survey covered the islands of the atoll and was conclusive enough
69

Select target paragraph3