No person may discharge into the ambient air from any single source of emission whatsoever any air contaminant which exhibits an opacity greater than twenty percent except that a maximum of sixty percent opacity is permissible for not more than one six-minute period per hour.

History: Effective January 1, 2019.

General Authority: NDCC 23.1-06-04; S.L. 2017, ch. 199, § 1

Law Implemented: NDCC 23.1-06-04; S.L. 2017, ch. 199, § 21