Emission limitations on or before April 1, 1972

Emission limitations on or before April 1, 1972. Emission limitations on or before April 1, 1972. All direct and portable sources on which construction or modification was commenced on or before April 1, 1972 shall meet the emission limits of this section. (1) No owner or operator of a direct or portable source may cause or allow emissions of shade or density greater than number 2 of the Ringelmann chart or 40% opacity. Exceptions listed in s. NR 431.05 shall apply. (2) No owner or operator of a direct or portable source located in subregion 1 of the Lake Michigan Intrastate AQCR or in the Southeastern Wisconsin Intrastate AQCR may, after July 31, 1975, cause or allow emissions of shade or density greater than number 1 of the Ringelmann chart or 20% opacity. Exceptions listed in s. NR 431.05 shall apply.