SUBJECT:

Radicsogical Survey of =

.. Contaminated by BRAVO

that one survey meter could not be properly zoro adjusted.

The four rem

AN/PDR-39, still operated cfficiantly and scomed to be in good working or¢

Onc (1) cach Bockman MX-5, and one (1) cach AN/PDR-27A was brougt
ior any low intonsity checks nocessary. Two (2) cach calibratcd AN/PDR-T!

on hand to scrvo as spares in the ovont of operational failuro with the N

None of those instrummts woro roquircd.

&

Tho avoragc and maximum gamma dogo rates measurod on tho various

of cach atoll arc plottcd in Figurcs 1 through 5, All masuroments woro o
waist hoight unless othorwiso indicatcd, Tho mximum roadings do not inc]
measurcments made with the instrument noxt to a contaminated surfaco.

Detailed surveys were made of all the inhabitcd localitics,

Typ!

readings are givon in Tablos 1 and 2 for the nativo villago of Rongclap I:

and the TG 7.4 camp on Mniwctak Island.

‘In gcncral, the villages and the

appearcd te have slightly lowcr avcrago dose ratcs than the romaindcr of 1
island. This can perhaps be ascribed to difforcnt gcomctry of the contami
and to slightly grcatcr penotration into the looso gravol in the nativo v:
The dose ratcs inside the nativo huts appoared to bo almost the same as tt

rate outside.

The dose ratc in the middlo of the military barracks, tnt:

shacks was 1/3 to 1/2 that outsidc, This reduction is probably largely a

effect. The dose rate foll off rapidly on the beach bclow the high tide
Thero was no cvidence of rain washing off thc contaminatcd mtcrial. The
on the windward sides of thc islands appcared to be slightly above avcrag:
tamination.
TABLE 1
TYPIC..L READINGS IN RONGEL\P VILLAGE - 8 MARCH

Location

Dosc_Rate_(mr/nr)

Rongelap Island (average)
Center of village

375
280

Near contral cistern
Near southern cistcrn

300
220

Near northern cistorn

350

TABLE 2

Sr, WOUIS PAC

TYPICAL READINGS IN CAMP ON ENTWETAK Is. - 10 MARCH

Location
Eniwetak Island (average)
Mess hall
Tent, cdge of main camp
Latrinc

Slecping quarters

Outside Dose

Inside Dose

(mr/hr)

Ratc_(mr/hr)

280
220
270

-110
175

“" 260

260

Dispensary

220

3

.

160

90

110

Select target paragraph3