OPERATION HARDTACK I
TATE:
PPG Time
9 June 1956
TIME:
1115
- Umbrella
Sponsor:
GMT
6 June LYdo
SITE:
2315
DOD
PPG - Eniwetok - NNE of
Henry
11° 22'
162° 13'
51"
o9"
N
E
Site elevation:
Sea level
Water depth:
150 ft
HEIGHT OF BURST:
150 ft underwater
TYPE OF BURST AND PLACEMENT:
Sub-surface burst on lagoon
bottom
REMARKS:
The pattern was obtained from a total of about 80 points which is
really too few to place much reliance on the rather pronounced lobing
of the downwind contours.
"Nearly all of the total gamma dose oceurred
within 25 minutes after zero time and was due to the passage of airborne radioactive material.
Gamma doses in excess of l00r occurred
within the first 15 minutes at downwind distances less than 14,000 feet.
The residual field due to deposited radioactive material was relatively
insignificant, although radioactive foam may represent a radiological
hazard."
238