
(from the article `environmental works`) ...required in the United States and other developed countries. When more than 85 percent of total solids and BOD must be removed, or when dissolved ... When the intended receiving water is very vulnerable to the effects of pollution, secondary effluent may be treated further by several tertiary ...
Found on
http://www.britannica.com/eb/a-z/t/28

process utilized to remove practically all solids and organic matter from wastewater. Granular activated carbon filtration is a tertiary treatment process. Phosphate removal by chemical coagulation is also regarded as a step in tertiary treatment.
Found on
http://www.chemicalglossary.net/definition/1570-Tertiary_Treatment

process utilized to remove practically all solids and organic matter from wastewater. Granular activated carbon filtration is a tertiary treatment process. Phosphate removal by chemical coagulation is also regarded as a step in tertiary treatment.
Found on
http://www.hach.com/chemGlossary

Advanced cleaning of wastewater that goes beyond the secondary or biological stage, removing nutrients such as phosphorus, nitrogen, and most BOD and suspended solids.
Found on
https://www.encyclo.co.uk/local/20094
No exact match found.