DOGWOOD
OPERATION HARDTACK
1,
The DOGWOOD device was detonated on a barge one mile southwest
of Janet Island, Enivetck Atoll, at 0630M, 6 July 1958.
The cloud rose
immediately oAee: stabilized aE. the
base levelled off at 35,000 feet.
Radar fixes from the weather radar at
Fred indicated a movement of the main body of the cloud of 330 degrees
at 17 knots.
Aircraft reported that the cloud did not shear during the
first hour.
2.
The P2V started the lagoon survey at 0645M and completed it one
hour later,
No contamination was found eycept on Janet and the islands
downwind of ground zero.
and Janet, 35 mr/hr.
Alice read 1,000 mr/hr; Irene, 2,900 or/hr;
The helicopter survey commenced at 0845M and con=
firmed the above readings.
3.
Re-entry hour was declared at H+3.
The P2V was dispatched on a track of 260 degrees from Alice and
read 300 mr 35 miles out.
It was then sent due north of Pearl and found
unexpectedly an intensity of 700 mr at a point 25 miles north.
At this
time the P2V reported that his background would not fall below 130 mr/hr,
in spite of repeated attempts to wash himself off in rain squalls.
He was
instructed to land, and a replacement was called for.
4,
The standby P2V¥ was sent to the north to discern whether or not
contaminated air was moving eastward.
A reading of 180 mr/hr was taken a+
TAB A
ne
a