FORECAST FALL©OUT PLOT
flue of folleout estimated to occur 2 hours and 10 minutes aftor Hehoure
"he first cerca shown in the illustration around the maximum fall-out point is ~
nprroximately 250 square miles and the line inclosing this mroa indicates 6
rocntgen integrated infinity doso.
smiles, and 3 rocntgens, otee
The next aren is of approximatcly 759 square
This example represents the prediction that may
have been made for UPSHOT/KNOTHOLE, Second Shot on 24 March 1953.
It is surprising
how closely tho actual fall-out approximated the above predictione The maximum
frileout at Lincoln Mince (48 miles from ground zoro) occurrcd at H¥2 hours and had
‘“s value of from 4 to 5 roontgen infinity dosc.e
Ground rendings at Synnyside to
Adaven (North to NortheBast of Lincoln Mineo) further verifiod the forccast plote
tho tclemetering station approximately 15 miles north of ground zero verificd the
ulose in falleout.e. This mcthod of snalysis must be used with cautione I[t should
be remembered that this procedure applies only to 300 ft.s tower shots at NIG and
when the cloud top reaches 36,000 to 45,000 fte msl (10 to 50 KT bombs). If the
tower heights are lowered to 200 or 100 fte, of if the bombs aredetonated on the
surface the contamination will increase by sovernl ordcrs of magnitude. If the
ceguivalent bomb yield is significuntly less than 14 KT thon the cloud may only
rvse to 15,000 to 20,000 fte msle Under such an evontuality the maximum fall-out
will occur much closer to ground zero (within o radius of 20 to 40 miles), and
the time of falleout will be more nearly one hour after Hehoure
.
@e
th yn , buhes Sara
Ne Me LULCJION
Major, USF
es
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oy
Control Officer
Caamepenren*