about 58 tines less than the maxizun permissible ascunt.
Mormal factors of
@ilution by additional rainfall and/or by the influx ef lesser ecxtazinated
be exPr ited tu
ground water vouldreduce the level of activity.
~
dix
Considerable effort has and is being mede to evaluate hazards fron
airborne radioactive materials, including fission products, There are esr
tainly many unansvered probless including the possible hasard from a single
particle in the lungs.
Despite the uncertainties and as yet incomplete
enalysis of the inhaletion hasard, the preponderance of evidence today is —
that the external gamma haserd fron fallout is the more liniting factor of
the two®,
(Eowever, see discussion on food contanination.)
During Upshot-Knothols quite complete data were eollected of soncen-
trations ef airborne activity on about 150 occasions in some 40 different
localities within
200 niles of the Bevada Proving Grounds,
These inaluded
monitoring of all detonations, Histograms vere made of air concentrations
versus tine after detonation for 30 occasions and estizates were meade of
doses to the lungs,
These data for the five comamities showing the highest
air concentration are given in Table YI.b. The histogram for St. George (the
high"2s hour average concentration of fallout ever measured {n a populated
area) 4s reproduced in Appendix J.
®22 Hoc Committees Meeting,
Washington, D.C.
January 20, 1954.
ay ms
Ria J
Noe