SUBJECT;
Radiological Survcy of Downwind tolls Vontaminated by BRAVO
that onc survey motor could not be properly zcro adjustod.
Tho four remining
AN/PDR~39, still operated cfficicntly and scomed to be in good working order,
@nc (1) cach Bockman MX-5, and one (1) cach AN/PDR-27A was brought alon:.
for any low intonsity checks noccssary.
Two (2) cach calibratcd AN/PDR-T1B, worc
on hand to scrvo as spares in the ovont of opcrational failure with tho ‘N/PDR~3:
None of these instrummts wore roquircd.
6. Tho average and mocimum gamma doso rates measured on tho various island:
of cach atoll are plotted in Figures 1 through 5, All measurements wore mde at
waist hcight unlcss otherwise indicatcd,
The mximum readings do not include
measurements mado with the instrument noxt to a contaminatcd surfaco,
Detailed survoys were made of all the inhabitcd localitics, Typical
readings aro given in Tables 1 and 2 for the nativo villago of Rongclap Island,
and the TG 7.4 camp on Iniwctak Island.
In gencral, tho villages and the camps
appeared te have slightly lowcr avcrago dosc ratcs than the romaindcr of tho
island, This can porhaps be ascribed to different gcomctry of tho contamination
and to slightly grcater penotration into the looso gravel in the native villagss.
The desc ratcs inside the nativo huts appcarcd to bo almost the samo as the doso
rate outside. The doso rato in the middlo of tho military barracks, tonts, and
shacks wes 1/3 to 1/2 that outside.
This reduction 4s probably largely a geomet
effect. Tho dose rate fcoll off rapidly on the beach below the high tide mrk.
Thero was no cvidence of rain washing off the contaminated mtcrial. The foilae
on the windward sides of the islands appcoarod to be slightly above average contamination.
TABLE
1
TYPICAL READINGS IN RONGEL‘P VILLNGE — 8 MARCH
Location
Dosc Rate (ar/nr)
Rongclap Island (average)
375
Near central cistern
Near southern cistern
Near northern cistern
300
220
350
Conter of village
280
TABLE 2
TYPICAL READINGS IN CAMP ON ENIWETYK IS. - 10 Mir
Outside Dose
Location
Eniwotak Island (average)
Mess hall
Tent, cdge of main camp
°
COPIED /pg
LANL RG. ~
Dispensary
Rate (mr /fnr)
280
--
220
270
Latrine
Sleeping quartcrs
“= 260
260
7
Inside Dose
Rate (mr /nr)
~ 2D
wie
140
175