septic system is a natural method of treatment and
disposal of household wastes for homeowners who
live in an area where there is no municipal sewage
disposal system. It is estimated that there are
about 30 million residences in the U.S. thatuse on-site systems. For homeowners using a septic system
it important for you to know something about how
it works. This often-overlooked part of your home
can be very expensive to repair or replace. A little
knowledge has the potential to save homeowners thousands
Although individual designs vary, a typical gravity
fed septic system is composed of three parts:
1. Septic tank -- 2. Distribution
box -- 3. Drain field or leachfield
and solids exit the home through toilets and drains
and end up in the septic tank. The function of the
septic tank is to separate solid material from the
wastewater. The solids are broken down by naturally
occurring bacteria that inhabit the tank.
tanks may contain one or two chambers. Scum is the
material, which floats on the top of the water in
the tank where aerobic (air breathing) bacteria
digest it. Sludge is undigested solid matter, which
settles to the bottom of the tank. Here anaerobic
(without air) bacteria digest some of the matter,
the undigested part must be removed periodically
by a licensed septic system pumping service every
2 - 5 years depending on use. In a septic tank that
is not pumped on a regular basis, undigested solids
accumulating in the tank may make their way to the
drainage bed where they will clog soil passages.
is the clarified partially-treated liquid portion
of household waste, which makes its way from the
tank to the distribution box where it is then distributed
to the various lateral lines in the drain field.
distribution box (D Box) can be made of concrete
drain field, also known as the leachfield, absorption bed, disposal field or seepage field performs the
task of accepting and processing wastewater, or
effluent, from the septic tank before it returns
to natural aquifers below the earth's surface.
typical drain field consists of several gravel-filled
trenches with perforated drainpipe buried just below
the surface of the gravel running the length of
the trenches. The effluent is distributed through
a distribution box to the various lateral drainpipes
exiting through the perforations into the surrounding
gravel bed. Secondary processing begins in these
beds as the effluent fills the trench then seeps
through the biomat and into the surrounding soil.
bio mat is a naturally occurring tar-like
substance that forms on the bottoms and sides of
the drain field trenches. It is made up of living
anaerobic (without oxygen) organisms, which feed
on organic matter in the wastewater. As the bio mat
matures it grows thicker slowing down the flow of
wastewater to the surrounding soil. This is part
of the natural process, which clarifies the effluent.
As the wastewater passes through the bio mat pathogenic
organisms and viruses are removed. On the outside
of the trench, beyond the bio mat where the soil
is not saturated, are living colonies of aerobic
(with oxygen) bacteria. These aerobic bacteria colonies
feed on the bio mat and keep it from becoming so
thick that wastewater will no longer pass through.
soil floods these aerobic bacteria colonies will
die off and no longer keep the bio mat in check.
The bio mat will grow too thick and drainage will
stop. This creates a major septic system problem. Mega Bio can solve this problem by replentishing the active bacteria in your septic system with a high quatity industrial-strength formula.