SUBJECT:

i

Radisiog.cal curve y of Downwird

toll¢ Contaminatod by BRAVO

that ono survey metor could not be properly zoro adjusted.

Tho four romining

‘N/PDR-39, still oporated cfficimtly ard scomed to bo in goed working ordor,

Qo (1) cach Bockman MX~5, and one (1) cach 1N/224,wes brought along

for any low intonsity checks ncecssary,

Two (2) cach ca

AN/PDR-T1LB, wer

on hand to servo as spares in the ovont of operational fadbape: with tho IN

None of these instrummts wor) roquircd.
6,

p23

3c

TBE

The average anc maximum gaoma doso ratos oemwiredon tho various islan’'s

of cach atoll arc plottcd in Figures 1 through 5.

‘11 masuremnts woro mdo at

waist height unless othorwise indicated, Tho maximum readings do not includo
moasurcments made with the instrument icxt to a contaminatod surfaco,

Dotailod survoys wero mado of all tho inhabitcd localitics, Typical
readings aro given in Tables 1 and 2 for tho native villago of Rongolap Island,
and the TG 7.4 camp on Mmiwetak Island, In goncral, tho villages and theo camps
appeared te havo slightly lowcr avorago doso ratcs than the romaindcr of tho
island. This can porhaps bo ascribed to difforcnt gcometry of the contamination
and to slightly grcatcr penotration into the leoso gravol in the nativo villagcs..
Tho doso ratos inside the native huts appoarcd to be almost the samo as the dosc
ratc outside. Tho dese rato in the middlo of tho military barracks, tonts, and

shacks was 1/3 to _/2 that outsido.

This roduction is probably largely a geomt

effect. The dose rato foll off rapidly on tho beach below the high tide mrk,
Thore was no cvidence of rain washing off thc contaminated mtcrial. The foilnag
on the windward sidcs of th tslands appoamd te be slightly above avcrago con
tamination,
TABLE

L

TYPICAL READINGS IN RONGZLAP VILLAGE — 8 MARCH
Location

Dosc Rate (ar/nr)

Rongeolap Island (avcrag:
Conter of village

375
280

Near contral cistern
Near southern cistorn
Near northern cisterr

300
220
350

TABLA2

TYPICAL READINGS IN CAMP ON =NIWETGK IS. - 10 MARCH

;

Location
Eniwotak Island (avoragc'

Mess hall

sutside Dose

Yato (mr/nr)

28t

22o

Tent, cdg: cf main camp

we

Sleeping yar :r3

ol,

Latrinc

Dispensar ’

200;

i.

Inside Dosa

Rate (mr/hr)
_—

pele
175

=
160

90

Select target paragraph3