A Polishing Filter (or also known as percolation area) purpose is to partially treat and dispose of the effluent from the wastewater system or septic tank. bioCycle™ provide a complete solution by designing, supplying, installing and certifying the polishing filter.
A percolation area is the drainage area installed after a septic tank its function is to fully treat the effluent from the septic tank and dispose of it.
A polishing filter is the drainage area installed after a wastewater treatment system its function to only partially treat the effluent and dispose of it.
In order to design a polishing filter a site suitability assessment (percolation test) needs to be carried. The design of the polishing filter will be based on the findings of this assessment and a determination of the loadings that the system will be receiving.
Sub surface soil polishing filter – This type of system is suitable for sites that have deep subsoil and a significant depth (>1.7m) to the water table or bedrock.
Raised soil polishing filter – This type of system is suitable for sites where there is a high water or bedrock. A mound is constructed the height of which is dependent on the water table/bedrock level on the site.
Pumped discharge sand polishing filter – This type of system is suitable for confined sites or where additional effluent treatment may be required.
The wastewater industry is unregulated and the current misleading certification offers little protection to homeowners. Under the Building Regulations & Water Services Act homeowners are responsible to ensure that their system is properly designed, installed & maintained and does not cause pollution.