Reconsidered EPA Boiler MACT / GACT Rules

1. Reconsidered EPA Boiler MACT / GACT Rules Steve Schliesser Engineer, Planning Section Division of Air Quality Feb 19, 2013 - Outside Involvement Committee Meeting

2. Reconsidered Boiler MACT for Major Sources –Key Changes and Highlights • 21 Boiler / Fuel subcategories for units > 10 million Btu/hr heat input - New subcategories for light (#1, 2) and heavy (#4 - 6) oils along with wet and dry biomass fuels • Higher PM emission limits for each fuel oil / biomass subcategory • Higher CO emission limits based on new data showing variability. • Lower emission limits for other pollutants / subcategories • Gas fired units subject to annual tune-ups but no emission limits • All affected units subject to one-time energy assessment • Nearly all NC affected facilities covering ~1,000 boilers have 112(j) permits shielding Boiler MACT compliance up to May 20, 2019 • Existing units Boiler MACT compliance date: - with 112(j) permit = May 2019; without it = January 2016

3. Reconsidered Boiler GACT for Area Sources – Key Changes and Highlights • Initial notification due January 20, 2014 • Initial tune-up and energy assessment compliance date extended 2 years to March 21, 2014 - ISO 50001 energy assessment considered equivalent • Existing dual-fuel units switching from gas to coal, biomass or oil now considered ‘existing’ units  • Tune-ups every 5 years, instead of every 2, for seasonal, limited use, small oil-fired, and boilers with oxygen trim • No PM limits for new boilers with < 0.5% sulfur oil • Higher mercury and CO emission limits for coal boilers • Clearer, broader definition of biomass fuels and energy assessment requirements • Gas fired units not subject to tune-ups or emission limits