OPERATION HARDPACK I TATE:
TIME:
PPG Time
12 May 1958
0550
Fir
Sponsor:
GMT
11 May 19538
1750
SITE:
UCRL
PPG - Bikini - SW of
Charlie 4,000 ft from
nearest edge of the island
11° kl!
165° 16'
a7"
25"
Site elevation:
HEIGHT OF BURST:
N
FE
Sea
ievel
9.88 ++
TYPE OF BURST AND PIACEMENT:
Surface burst trom burge on
water
CLOUD TOP HEIGHT:
9C,0CO ft MSL
CLOUD BOTTOM HEIGH?:
NM
REMARKS:
Only individual island dose rates are available.
These were obtained
from Radiological Safety organization helicopter surveys at Ht4 hours.
The helicopter survey technique called for the pilot either to land the
aircraft at the desired spot, so that a ground reading could be obtained, or to make a slow pass over the desired spot at an elevation
of 25 feet.
Readings taken at 25 feet were multiplied by a factor
of 2 in order to obtain a reasonable approximation of the true ground
reading.
The basic instrument used in the aerial surveys was the
AN/PDR-39 survey meter modified to read up to 500 r/hr.
The t-1:2
decay approximation was used to extrapolate the Ht hour dose rate
readings to H+tl hour.
193