Treated effluents discharged from the BIOROCK system are of very high quality and can be disposed of into the natural environment. The purification efficiency results expressed as a percentage are as follows, BOD: 99%, COD: 96%, SS: 99%.
In the UK, there is a requirement to ensure the subsoil infiltration of the treated effluent, and discharge into the tank or into a natural environment is subject to authorisation. However this may vary depending on the nature of the land and other specific factors relating to the local set-up. It is also possible that the underground irrigation of an ornamental garden may be permitted. The use of treated water for watering plants intended for human consumption is prohibited.