In addition to the ambient air quality standards set forth in section 584-A, any Class II region or part thereof within the State is subject to a maximum allowable increase in concentration of particulate matter, sulfur dioxide and nitrogen oxides over the baseline concentration of that pollutant. An increase shall not be exceeded more than once annually for any period other than an annual period. The maximum allowable increase consists of: [1989, c. 860, §3 (AMD).]