7. 'primary treatment' means treatment of urban waste water by a physical and/or chemical process involving settlement of suspended solids, or other processes in which the BOD5 of the incoming waste water is reduced by at least 20 % before discharge and the total suspended solids of the incoming waste water are reduced by at least 50 %;
7. reovee eelselitus — asulareovee füüsikaline ja/või keemiline puhastamine, mis hõlmab asulareovees sisalduvate hõljuvainete selitamist või muid protsesse, mille käigus siseneva reovee BHT5 väheneb vähemalt 20 % ning hõljuvainete osa sisenevas reovees vähemalt 50 %;