G.
Water and Air
Background Information Water Contamination of water supplies does not constitute a major source
of intake of radioactive fallout debris.
In the case of surface water
supplies there is a very large dilution factor.
In the case of under-
ground nuclear detonations the fission products are restricted largely
to the immediate vicinity of the detonation due principally to two
factors.
Firstly, approximately 90 percent of the fission products are fixed
in glassy type material formed by the detonation.
Secondly, ion
exchange between such key fission products as strontium-90 and cesium-137,
and the soil results in almost all of the remaining activity being
_
perhaps tens of hundyeds
absorbed within a matter of feet/away from the source**-.
In addition
to fission products, tritium may be formed in varying amounts.
This
radioisotope probably is not greatly influenced by the two factors mentioned in the previous paragraph and must depend upon the dilution
factor for reduction of the concentration in the water - at least for
underground detonations.
For above ground or cratering shots, the
tritium largely escapes into the atmosphere where very large dilutions
occur.
Theoretical calculations suggest it may be possible for above
acceptable concentrations of tritium to be present in the amount of
water present around ground zero of some underground nuclear detonations? 6a. .
27
ad