Wastewater Characterization

Effluent Guidelines and the “Cluster Rule”

EPA establishes national, technology-based regulations, known as effluent limitations guidelines (ELGs), for direct dischargers and pretreatment standards for indirect dischargers to control discharges of pollutants in effluents from certain industrial source categories.  The pulp and paper industry and timber processing industry are two of about 60 such categories.  EPA reviews existing effluent guidelines annually.  In odd-year reviews, EPA screens industrial dischargers through a toxicity ranking analysis (TRA) that identifies and ranks those categories by their estimated releases of pollutants.  In even-year reviews, EPA examines additional hazard data sources and conducts alternate analyses to enhance identification of industrial categories for which new or revised effluent guidelines may be appropriate.

EPA’s most recent update of ELGs for the pulp, paper, and paperboard category was in 1998 and is frequently referred to as the “Cluster Rule” because of the combined water and air rulemaking activity.  NCASI prepared several documents to assist members with ongoing implementation of ELG provisions.