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Know your Weather


What is a Septic Tank?
What is a Pump Tank?
What is a Holding Tank?
What is a Conventional Drainfield?


What is a Septic Tank?
The septic tank is the most cost efficient method available to treat residential wastewater. But for it to work properly, the right size or capacity of a septic tank must be chosen for your household size and soil type, and you need to maintain it regularly.

A septic tank is an enclosed watertight container that collects and provides primary treatment of wastewater by separating solids from the effluent. It removes the solids by slowing down the wastewater flow in the tank and allowing the settleable solids to settle to the bottom of the tank while the floatable solids (fats, oil, and greases) rise to the top.

To provide time for the solids to settle, detention time should be at least 24 hours. Some of the solids are removed from the water, some are digested, and some are stored in the tank. Up to 50 percent of the solids retained in the tank decompose; the rest accumulate as sludge at the tank bottom and need to be removed periodically by pumping the tank. Tanks should be pumped by a licensed pumper as required by local and/or state regulations for most residential systems and inspected regularly.

What is a Pump Tank?
Pump tanks are containers that in most cases collect treated wastewater to be pressure-dosed to the next component. This tank can be dosed with timer controls, that dose a set amount of effluent at specific time intervals, or they can be demand dosed, which dose the effluent when a certain volume is collected in the tank. The pump tank collects wastewater until it is dosed into the next component in the onsite wastewater treatment system.

The tank must be watertight to prevent wastewater from seeping out and groundwater from entering. It must be big enough to hold the amount of wastewater distributed during dosing. It also must be able to store a minimum amount of wastewater for the pump to operate properly, and to store a certain amount of wastewater after a high-water alarm is triggered.

What is a Holding Tank?
 Holding tanks are generally considered a collection and storage device. Use of a holding tank in an onsite wastewater treatment system incorporates the services of a sewage pumper/hauler and off-site treatment for the sewage generated.

The tank is a watertight device capable of storing several days of wastewater generated in the residence and in some applications, by commercial sites. Settling of the solids may occur during storage. However, all material in the holding tank is removed during pumping.

What is a Conventional Drainfield?
 
A conventional soil treatment area involves gravity distribution from the septic tank to a gravel filled trench. The main function of gravity distribution systems is to accept, store, and distribute wastewater so it can be dispersed into the soil and environment. Technologies available for gravity distribution of wastewater into soil can be divided into media filled (gravel, sand, polystyrene, etc.) and open storage types (chamber, gravel-less pipes).