Regulation & law · 27/12/2019Updated: 10/17/2026 · 1 min read

EPA Approves Indiana's Limited Maintenance Plans for 1997 Ozone NAAQS

The Environmental Protection Agency (EPA) has approved a revision to Indiana's State Implementation Plan, which includes limited maintenance plans for six areas in the state to maintain the 1997 8-hour ozone National Ambient Air Quality Standard (NAAQS) through the end of the second 10-year portion of the maintenance period.