40 CFR § 63.1356
Sources with multiple emissions limit or monitoring requirements
June 9, 2020
If you have an affected source subject to this subpart with a different emissions limit or requirement for the same pollutant under another regulation in title 40 of this chapter, once you are in compliance with the most stringent emissions limit or requirement, you are not subject to the less stringent requirement. Until you are in compliance with the more stringent limit, the less stringent limit continues to apply.
[80 FR 44791, July 27, 2015]