Would you be able to tell what standards and / or resolutions an industry should respect by releasing its treated effluent into a receiving body?
Try to answer this example: An industry, installed in the city of São Paulo (SP), intends to launch its treated effluent into a receiving body within the territorial limits of its State. The treated effluent from this TEE had a BOD concentration of 55 mg / L, and the removal efficiency of this parameter was 70%. According to the Federal Law pertinent to this case (Article 16 of CONAMA Resolution No. 430), the treated effluent from this industry can only be released to the receiving body if the minimum efficiency of BOD removal is 60%.
In contrast, in the state of São Paulo, Article 18 of State Decree 8468 establishes that the treated effluent from this industry can only be released in a receiving body, if it has a maximum concentration of BOD of 60.0 mg / L, or the removal efficiency of this parameter is 80%.
In this case, which Legislation the owner of the ETE must attend, Federal or State? If you answered “State Legislation”, you got it right, because the São Paulo State Law is the MOST RESTRICTIVE! In Brazil, the emission of effluent from any ETE must comply with the Federal, State or Municipal Law, whose limits of effluent release parameters are the MOST RESTRICTIVE.