Biosolids Management Strategies for SSI MACT 129 Rules

The United States Environmental Protection Agency (USEPA) has initiated numerous environmental regulatory changes with significant implications for future biosolids processing at Publicly Owned Treatment Works (POTWs). Of particular note are the classification of sewage solids combusted at a POTW as “solid waste” and the redefinition of rules for these sewage sludge incinerators (SSIs) to require Maximum Achievable Control Technology (MACT). Under MACT rules, more stringent emission limits will be imposed on current multiple hearth and fluidized bed SSIs as well as much more stringent limits for “new” SSIs. The proposed regulation will force POTWs to consider biosolids management strategies to continue with SSIs or change management processes if their SSIs can no longer meet the new regulations.This paper reviews the new MACT 129 regulations; discuss options for MACT compliance, and presents costs associated with compliance.