Wisconsin’s Division of Natural Resources (WDNR) adoption of the NO2 standard may be an additional permitting hurdle for sources with high short-term (hourly) emissions of nitrogen oxides (NOx) or SO2, such as reciprocating internal combustion engines and other combustion sources, according to a September 23, 2016 Trinity Consultants report.

Effective August 1, 2016, WDNR revised the state implementation plan (SIP) to adopt the federal National Ambient Air Quality Standards (NAAQS) for sulfur dioxide (SO2) and nitrogen dioxide (NO2) for the 1-hour averaging period. These standards are shown below:

• 0.075 ppm (196 µg/m3) SO2 primary 1-hour average concentration
• 0.100 ppm (188 µg/m3) NO2 primary 1-hour average concentration

These standards were originally promulgated by the EPA in 2010, but were never incorporated into the Wisconsin state implementation plan (SIP). Modeling to demonstrate compliance with the 1-hour standards may now be required for certain construction and operation permit actions moving forward.

The WDNR plans on addressing public comments and implementing additional guidance and tools throughout the rest of this year.

What this means to you
Wisconsin’s revised SIP to adopt federal NAAQS for SO2 and NO2 for the 1-hour averaging period may be a permitting hurdle for sources with high short-term (hourly) emissions such as reciprocating internal combustion engines.

MIRATECH can help
Contact MIRATECH to learn more about NOx controls for your stationary engines.