The Key West citizen. [volume] (Key West, Fla.) 1879-current, 1950-04-03
Behind The
World News
~ WILLIAM JoLEScH.
Associated Press Writer

Associated Press Writer
The defense of Alaska has run
into more opposition from nature
herself. The name of this new
natural impeachment is perma-
fFost--a type of ground that is
frozen all year long in Central
and Northern Alaska It's a type
az opposition that can be over
come, but il is costly both in time
and money.
This natural obstacle is eSpec-
Tally inter esting now at a time
when there has been a call to
strengthen Alaska and its major
aiFfields against surprise attacks.
General Eisenhower has suggest
ed that our aerial fortress in
Alaska be reinforced by keeping
well trained men there at all
times, Eisenhower also wants a
radaF cieen to detect and warn
against air attacks.
~ the Generals proposals are
carriets out, Alaskan air bases
doubtless viii have to be ex-
panded great deal. New ones
MAY have to be built And that's
where nature will run in some
interference.
The DOGGY of permafrost was
little known until World War II.
when the Army did SO much
huilding around Lall and Edison
Fields near Fairbanks. Since
then, the military engineers have
learned a lot about it. They have
learned especially that they must
give their first attention to perm
afFost when making any new
The engineers know, for ex-
ample, that permafrost is quite
deceptive. AS long as this type
% ground is left alone, it offers
ro1pposition. But once the mos
sy vegetation is removed from
the kuTface, it begins to act up.
This vegetation acts as an insula-
ton against the summer sun.
When the insulation is scraped
off, the heat penetrates the froz-
en- ground. thaw sets in and the
soil becomes mushy like quick
sand.
The permafroSt usually is not
Just a shallow imperfection in
the soil. II may extend from two
to 100 feet below the top, but
the average depth is Is feet
Much of it is fine silt. However,
not all the ground of Central
Alaska is so afflicted. Permafrost
Is found in patches, and many
areas are entirely free of it.
8. But because of its tricky ma
tlre, military engineers have to
tread carefully, and this has not
always been possible or practi-
cd. When il has been necessary
to build on permafrost, the
buildings have settled badly. And
IL runways or heavy duty roads
are constructed on it, they usual
" crack, sink or buckle, unless
special precautions are taken.
Z Engineers have learned that
they must resort to deep excava-
tons to conquer the hazards Of
hlnlding on permafrost ground
This means they must dig out .
very large space under and
s1o0nd the building area and
hen Jill all but the basement
Aiel coarse gravel
Here is what permafrost means
u dollars and cents. In excayat-
ina Easements for typical row
Of eight houses in the United
States, only LOO cubic yards of
earth would normally have to be
moved.
But to do the same job in Alas
ka, more than Six-thousand cubic
yards of permafrost have to be
dug out, and some five-thousand
cubic yards of gravel have to be
back-filled. The total cost is more
than $4,000. The same Job
would have cost a little more
than $1,000 in this country.
SCR take the problem of build
ing heavy duty road. In this
country, engineers usually exca-
vate for two and one-half feet be-
fore hitting the roadbed. But in
Alaskan permafrost, they have
TO dig almost ten feet.
Right now engineers are try
ing new insulation technique
In building small homes around
Ladd and Edison Fields, they are
scrapping away the surface moss
and putting a layer of gravel on
the top soil. about Is to 36 inches
deep. On top of this layer OF
gravel, they lay concrete slabs as
foundation for the houses. The
military engineers believe the
gravel will act as insulation and
keep the permafroSt fronl melt
ing. This new technique will
probably be tested many times.
- Most notpntial II OiI-orOd,,o