was secured at H # 30 hours andj the ship opened at H # 33 hours,
The LST-611 encountered fallout only on D # 1 when at about
0900 (H 4 27) a level of about 0,2 mr/hr was obtained.
However, the
radiation level on the deck was about 10 mr/hr in the puddles reMaining after the washdown was secured.
This activity probably came
from contaminated sea water being pumped through the washdown system
when the ship traversei the fallout area,
Washiown Tvaluation
Radiation intensity levels aboard YAG-40 appeared to be satisfactory
for the purpose of evaluating the washiow system and have been given
precedence over those of the YAG-39,
It will be some time before the
YAG~39 data are available.
The recoris from two continuous gamma intensity recorder stations
forward in the unwashed area have been reduced and compared with sim~
ilar stations under the washdown.
Survey ani film pack data are not
available at this time for comparison purposes,
The gamma stations
iniicate that at the time the washicwn was secured the percent effectiveness was about 85% for dose rates and 82% for total dose accumulated up
to that time.
Visual inspection of the YAS-40 upon her return to Eniwetok for
decontamination showed the forward half of the ship completely covered
by the fallout material, all the decks taking on a coral-white sheen
that obscure? their usual navy grey cclor.
An appreciable amount of
fallout material was observed to have collected under the washed area
aft.
It appeared to consist of caleium varticles about 200 micron
average diameter of high enough mass to be effectively held up by such
COPS uz
PINE RE
“ib
~ 5R .