Polk County observer. (Monmouth, Polk County, Or.) 1888-1927, 1904-07-15
SUCCESS OF SEPTIC TANKS
New Plan OF Sewage for Private
Residences Is Rapidly Grow
ing In Favor.

1 koluCC bu6 JQDllCdulOu Ol GLG SuCC6SS-
full installation of the septic sewage
tanks at the Chemawa Indian School,
the Asylum Farm at Salem, and at
other places, many inquiries are daily
being made from districts suburban
to Portland and from country sections
where there are no sewerage facilities,
asking questions concerning the con-
struction of the tanks and the in
stallation of the service
The system is being adopted at the
Mount Tabor Sanitarium, and DR..
W. 7. Williamson, of that institution,
has explained, for the benefit of those
desiring to know something of the
theory of the process and the con-
struction of the septic tank.
A septic tank is, freely translated, a
case of bug eat bug. 1t is as old as
the cesspool of the farmhouse, and
according to medical authorities, yet
in it's infancy, not being understood
but by few people who have taken
time to investigate the subject.
There are two bugs mixed up in the
eternal conflict of nature to purify
conditions, but for these to do the best,
peculiar conditions must be observed.
1t is the province Of the septic tank to
provide these conditions. In the first
place, the whole success of the process
depends upon lack of current. The
contents of the tank must be as nearly
absolutely quiescent as is possible.
In the second place, the tank must
have a certain specified size, pro-
portionate to the size of the building
to be served. In order to do away
with as much of the disturbing current
as may be, it is necessary to place the
point of deposit for the sewage as
nearly on a level as possible with the
pipe of ingress at the tank. This is
done to cause a slow feed into the tank.
Again, the pipe of ingress must be
bent downward from the surface, the |
point being about half way from the
surface of the contents to the bottom
of the tank, being SO arranged as to
create the least disturbance in the
fluid mass by the influx from the pipe. |
The pipe of egress is constructed
like the other, being bent downward, |
the whole scheme of construction be-
ing to allow the first fluid emitted into
the tank to escape first, with as little
disturbance as possible; the more
complete the stagnation, the more sue
cessful the process.
The tank itself is made of brick, |
stone, or cement, and must be tightly |
covered to exclude the light.
The theory of septic sewage is the
warfare of microbe, or bacteria, upon
decaying matter. 1t is a process of
chemical change, induced by these
bacteria.
There are two active agents in the
sewage process, the aerobe, the bac-
terium having great affinity for
oxygen, and which thrives and works
in the light, and the anaerobe, the
of the first, which perishes in the
light, but which in the dark and
oxygenized contents of the septic tank,
is highly vitalized argosm, which
seizes and devours every atom of
nonoXygenic nature coming into it's
reach.
The anaerobes live and multiply in
great numbers on the under surface
of the crust forming on the top of the
fluid contents of the septic tank, and
as fresh material is emptied into the
place, it is attacked by these bacteria,
and changed from a poisonous sub
stance into that which is perfectly
harmless and nonpoisonous.
1t is estimated by medical authori-
ties that about 78 per cent of the
poisonous contents of a rightly-con-
structed tank will be converted into
harmless, tasteless, odorless and I
oolorless fluid by the chemical changes {
in the process of fermen-
Iation. 1t is also estimated that 10
per cent of this poisonous remainder
can be emptied onto the surface of the
ground or into a stream without t
detrimental effect to the people. There t
is, then, a small margin left which is ]
not affected by the anaerobe, but
which will be converted by the aerobe {
when it emerges into the air or water {
at the outlet Of the tank.
The outlet is so constructed, then,
hat the outgoing liquid passes
through filter in which it is exposed j.,
% the light and air, and when it
at the final outlet, has neither
aste, color nor odor. All the solid
natter has been converted by chemical
change into gas, which is neither !,
harmful nor poisonous. The change !.
s so complete and the process so :
thorough that in a years time there :
vas left in the tank at the Insane =
Asylum Farm a residunm Of less than