OK HB2976

Department of Environmental Quality must promulgate rules establishing numeric water quality criteria for aluminum in Oklahoma surface waters by December 31, 2028

Criteria must comply with Section 303(c) of the federal Clean Water Act, follow current EPA guidance including hardness-based or water-chemistry-based equations, and incorporate site-specific conditions such as water hardness, pH, and dissolved organic carbon

Aluminum criteria must be applied to all Oklahoma Pollutant Discharge Elimination System (OPDES) permits where aluminum may be discharged, including required monitoring, reporting, and water-quality-based effluent limits

Aluminum criteria must be included in each triennial review of Oklahoma Water Quality Standards, with revisions submitted to EPA for approval as needed

Effective date is November 1, 2026