11 Miss. Code. R. 2-1.7
If any single source of emission or combination of sources of emissions is found to compromise the ambient air quality in the State, beyond the limitations set forth in any national primary and secondary ambient air quality standards now or hereafter established by the Administrator of the Environmental Protection Agency pursuant to the Clean Air Act as amended December 31, 1970, ( Public Law 91-640) notwithstanding compliance with any maximum allowable emission rate allowed by this regulation, the Mississippi Commission on Environmental Quality may require such further reduction in emission from this or these sources as is necessary to obtain compliance with said national primary and secondary ambient air quality standards.
11 Miss. Code. R. 2-1.7