Inconsistency of regulatory legal acts often does not allow unambiguously determining the applicability of legislative requirements to a specific type of activity. The article provides an analysis of the concepts established in the legislation, as well as an attempt to understand the requirements for enterprises when handling sewage sludge from sewage treatment plants. Due to the imperfection of environmental legislation and the similarity of technological processes, the treatment of sewage sludge during its treatment at sewage treatment plants is often classified by regulatory authorities as waste disposal. Such categorization entails the need for organizations operating sewage treatment plants to obtain licenses. The absence of a license in such a case leads to penalties against the company operating the treatment facilities and its officials.