SUBJECT:
Radiological Survcy of Downwind .itolls Contaminated by BRi.VO
that once survey metor could not be properly zcro adjusted.
Tho four remining
-N/PDR~39, still oporated officicntly and scomed to be in good working ordor,
@nc (1) cach Bockman MX~-5, and one (1) cach AN/PDR-27A was brought alor
for any low intensity chocks noccssary. Two (2) cach calibratcd AN/PDR-T1B, wo:
on hand to scrvo as sparcs in tho ovont of operational failuro with the AN/PDR~
None of theso instrumants wero roquirod,.
6.
Tho avorago and‘ maximum gamma doso ratos measurod on tho various islar
of cach atoll aro plottod in Figures 1 through 5. All moasurements woro mdc ai
waist hoight unless othorwiso indicatcd, The maximum readings do not include
moasurements made with tho instrument next to a contaminated surfacos.
Dotailed surveys woro made of all tho inhabited lecalitics. Typical
readings aro givon in Tablos 1 and 2 for tho nativo villago of Rongclap Island,
and the 1G 7.4 camp on Mmiwctak Island. In gencral, the villages and the camps
appearcd to have slightly lowcr averago doso ratcs than the romainder of tho
island. This can porhaps bo ascribed to difforent gcomotry of the contaminatla
and to slightly grceatcr ponotration into the leose gravol in the nativo village:
The doso rates inside the nativo huts appoarcd to bo almost tho samo as the doe
rate outside. The doso rate in the middlo of tho military barracks, tcnte, and
shacks was 1/3 to 1/2 that outsido, This reduction is probably largely a gcom
effect. The dose rato fcll off rapidly on tho boach below the high tide mark,
Thoro was no cvidence of rain washing off the contaminated mtcrial, The foila;
on the windward sides of tho islands appcarod to be slightly above average con—
tamination.
TABLE
TYPICAL READINGS IN RONGELAP VILLAGE — 8 MARCH
Location
|
Rato
Rongolap Island (average)
375
Noar central cistern
300
Near northorn cistern
350
Conter of village
280
Near southern cistcrn
220
TABLE 2
TYPICAL READINGS IN CAMP ON ENIWET#K IS. - 10 MARGH
Location
Eniwotak Island (average)
Mess hall
Tont, cdge of min camp
Latrinc
Slecping quarters
Dispensary
Outside Dose
Inside Dose
Rate (or/hr)
Rate Xor/hr)
280
220
-~
pale)
“- 26
160
270
220
26
—
175
110 aOR
90