Last month, Trinity reported on several various air dispersion modeling updates being undertaken by the Wisconsin Department of Natural Resources (WDNR). Since then, the WDNR has published or released the following new information:

  • Air dispersion meteorological data that reflects a more recent five-year period (2011-2015) and includes the use of various regulatory default options per the recently updated Appendix W, such as the use of the ADJ_U* option. A memo describing the update can be found here.
  • Updated Prevention of Significant Deterioration (PSD) minor source baseline dates for particulate matter with an aerodynamic diameter less than 10 micrometers (PM10) and less than 2.5 micrometers (PM2.5), sulfur dioxide (SO2), and nitrogen oxides (NOx). These baseline dates and supporting information are posted here.

Additionally, keep an eye out for updates on the other topics covered last month: 1-hour nitrogen dioxide (NO2) modeling guidance and permit streamlining rulemaking!

For more information, please contact Jon Frost at (651) 275-9900 X-6.