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The Sr~90 studies have increased in scope and complexity, end the
overall program has, for some years, been global in extent, involving
physical, chemical, and biological investigations on land, in the oceans,
end in the air.
Known as Project Sumshine and directed at a full under-
standing of the physical and biological behavior of the Sr-90 produced
innuclear detonations, these studies are concerned with an unprece-
dented variety of scientific questions.
From the standpoint of its
vast geographic dimensions and the variety of scientific mechanims
involved in the investigation, Project Sunshine rivals the most compre-
hensive scientific studies ever umdertaken.
The factors that influence the behavior of Gr-90 begin in the
complex physics and chenistry of the fireball and the mushroom-shaped
cloud which forms after a nuclear detonation.
The height of the burst
above ground, the nature of the terrein, and the particle size of the
soil and debris sucked into the fireball, all influence the fallout
pattern.
When the particles descend to the earth's surface, they leave the
domain of the meteorologist and become involved in the physics, chenistry,
and biology of the soil.
leach from the soil?
How soluble is the Sr-90 in fallout?
Does it
At what rate is it incorporated into plants, and
how can this rate be expressea quantitatively as a fimction of type
of soil and type of plant?
These are a few af the questions that have
been studied in tracing the Sr~-90 into the first of the biological
links in the food chain_between soil and man.
The answers to these
and many mere questions have. been obtained by many investigators working
in neny lehoratories throughout the coimtry.
Dor ARCHIVES
SF