2.
NYOO 1621
Sampling
Observers at each typical fixed station collected 2. ¢
posing duplicate one foot ijjuarey of famed fiir,
Ine
stations throughout the worid mailed sar-les daily to t
WGULDWIDE FALLOJT FROM OPERATION CASTLE
Laboratory where the activity was mesmired.
The
arnt is still in effect as this is writtea, excen
were mo"
1, Introduction
During Operation Castle, the atomic weapons tests held in the Spring cf
' only temporarily durang the weapons t23%5s Nave apopypei ot.
Samp? ing and analysis techniques wera the sane aa tose asec turing
ation Upnote!:-th-le and other test series and thay are descrize. i:
1754 at the Cniwetok Proving Grounds, fallout monitoring «13 conducted
by the A.E.C. Health and Safety Latoratory (New fork Operations Office:
lier reports 1,2,3.
and the same agencies which had cooperate! in earlier survey3e
3-
The work was dona in these phases:
The maps, Figures 1 to 15, show the total fallout of beta a-tivits
fixed stations for each of six periods, tne five betwee
:
&.
Collection of fallout samples at fixed station:
conprising a
worldwide network and analysis of the samples at tue Health
amd Safety Laboratory,
be
Siailar sampling and analysis of fallout on Navy ships in the
Se
Assistance to the task force by the installation and maintenance of aucomatic radiation and airtorme dust monitors on
Pacific Islands, furnishing instruments for serial monit>ring
of the islands and providing technical instruction and guidance
Yaclfic.
.
in the operation of the aariat and ground insatrunents,
ad,
Jnvestigation of the feasibility of measuring fallout over «ne
cpen sea,
Fata Gueary presents the results of fallout sampling at fixed statics.
see ork referred to in "c" and "da" above will be reported separate,
Tae flued station data in greater detail and an analysis of it in rairRian Go meteorology will be reported by the Weather Bureau.
Ye aisplify cate handling, the ship samples were assumed to reore-#:°
enema Unto which the ocean was divided for convenience and in whi:..
ahige heappemed ta be wher tha dampies were taken,
The number ci .o..
Lae aath area varied from day to day and the muinber of days repre
Sg eomplee vas Siffermt or sath area.
For these reasons the
r
seu FA Sullable for reporzing in sum-ary form,
The; are best studie:
Bh ONO, 42 6 part of the general study being made wy the Weather Birr.
‘Be wipe vere weed in the sampling program to asgment the fixed stations
_ - ee ante tb eprallie queation might rezuire densn coverage in some ares cf
Results
Plosions and the sixth tasginning the day of the last ¢
18 days later,
Each period begins on the day of a bur
21 show the totals for all six periods,
is show in Figures 22 to W.
Fallout for Jun
For the purpose of ex*trapelation the activity
pigsions according to an arbitra.,
mie ac
rcations in the 9CO series, the
ait on ships was attriouted to ¢
out at other stations was attriluted to the i:
that all fallout tetween the farst anid second |
first.
Beginning in August the activity was a.
on April 10th, about the midpoint of the series.
SLi Was attire.
med Lo nave orar er awed
As usual the activity was assumed inversely
power of the age.
Total world fallout, e
beginning of the serie:
Uh megacuries.
In the vicinity of the tests
an estimate of fal.o:4
Measurements of r.
reported elsewhere, b
tenonstrated tnat act
out over amall spots J.
the o-ean,.
Estimated world fallout is 3.7 and 2.5 segacuries for J
The estimate for August is 1.2 megacuries, an increase of
over
Tl,
The average monthly fallout fer the three months of the weapony tet.
was only slightly greater, 1.5 megacuries.
ae BG
-6-<-