Conventional Septic Tanks
A conventional septic tank is the concrete vessel below the ground near the house. It is here that all the wastewater and materials that are flushed down the drain are deposited.
In a conventional septic tank there are 2 compartments. The first section is the Working Compartment (aka Trash Tank) and it is here where the solids in the wastewater settle to the bottom (Sludge) and the greases and fats float to the top (Scum) which leaves grey water in the middle. This process of separation plus the biological digestion of bacteria collectively support a major portion of the sewage treatment. The grey water which is the cleanest (in the middle of the tank) is allowed to migrate into the next compartment via a plumbing system. This keeps all solids contained within the Working Tank.
The second compartment is the Dose Tank. This is where the effluent is either pumped or siphoned out to the septic field. This tank may only use 30% of the total gallonage of the entire septic tank. Very little biological breakdown occurs in this compartment. The Dose tank will have a high water alarm set up to notify the homeowner if the pump or siphon system fails. This is mandatory and has saved many homes from a sewage backflow issue occurring in the basement.
It is critical that the septic tank be sized properly to meet or exceed the peak daily flow rates created by the household. An undersized or poorly maintained tank will not be capable of processing the effluent within the Working Chamber. This means that suspended solid materials will be forced into the Dose Chamber and sent to the septic field. This results in plugging and overloading the soil structure and eventually saturating and flooding the system. We recommend over sizing the septic tank as it is the main processing component in the septic system.