The objective of an on-site wastewater treatment system is to treat wastewater and return it to
the environment so that risks to health are not created, the impact on ground and surface water
is minimized, and the environment is not harmed.
On-site wastewater treatment systems use a septic tank or treatment plant for initial treatment.
The household plumbing collects waste water and sends it to the septic tank working
compartment which acts as a separation chamber. Heavy particles separate from the
wastewater and settle to the bottom to form a sludge layer. Lighter particles, mainly soap and
grease, separate and float to the top to form a scum layer. Using a baffle device the clearest
liquid from the center of the tank flows by gravity to the effluent dosing chamber. A pump or
siphon in the effluent dosing chamber will deliver the effluent to the final soil treatment
There are other options for initial treatment components, including manufactured package
sewage treatment plants, textile filter systems and incineration devices. These components, like
a septic tank, will receive all the wastewater generated by the facility they serve. These systems
will produce cleaner effluent and are considered to be advanced treatment systems. Cleaner
effluent does not clog the soil pore spaces of the final treatment component as easily as septic
tank effluent.
All initial treatment devices reduce the amount of organic material, dirt, grease, etc. However,
disease-causing organisms ( pathogens ) are not destroyed by initial treatment and it’s bacterial
action. In an initial treatment, methane gas and hydrogen sulfide gas are produced in the septic
The sludge and scum separated out in the initial treatment stage will need to be pumped out on
a regular basis.
The final treatment and recycling of effluent back to groundwater occurs in the soil. Natural
processes and soil bacteria will remove or alter the pollutant and pathogens in wastewater. With
suitable soil and adequate separation distances from water tables this effluent will safely return
to the groundwater.
The soil treatment of effluent occurs mostly through the action of aerobic bacteria. Aerobic
bacteria require oxygen if they are to do their job. In treating sewage they must have food and
water (effluent), are to breathe and suitable environment in which to live (soil). Thus a sufficient
depth of suitable soil is needed to allow the use of treatment field trenches to return effluent to
the soil. The Alberta standard of practice requires 5 feet of this suitable soil below the bottom of
the treatment field trench for septic effluent and 3ft for class 1 plant or advanced treatment
effluent. Treatment field trenches are typically 2 ft wide by 2 ft deep and will likely total more
than 400 lineal feet. In areas not having the required depth of suitable soil, imported suitable fill
material will be needed to construct a treatment mound or if adequate forested areas are on site
an LFH At-grade system may be used.
Pressure distribution is preferred for all systems. A pressure distribution system is a carefully
designed network of small pipes with small holes called orifices, connected to a pump.
Periodically the pump sends doses of effluent under pressure to the network of pipes. The pipes
are totally filled during each dosing cycle to ensure a uniform volume of effluent is distributed
from each orifice. This intermittent dosing allows the effluent to pass into the sand layer or
ground and then time for air to reach the soil before the next dose. Pressure distribution is
superior to gravity distribution and is required for a mound or an at-grade system. Pressurized
distribution makes use of the whole mound or treatment field area thus creating a longer life of
the final treatment component.
We at High Road Ventures are certified to design and install and maintain all the above
mentioned septic systems. We are very knowledgeable and experienced in this industry and
pride ourselves in our quality of work and attention to detail. We use only the most durable and
highest quality tanks, pumps and accessories. We believe in customer service before, during
and after the job is complete. Please call us with any questions and we can discuss what will
work best for you and your property.

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