Significant modifications involving the procedures of Subpart 5 of this part shall be used for applications that:

1. (1) Involve new applicable requirements;
2. (2) Are modifications under any provision of Title I of the Act;
3. (3) Involve significant changes to existing monitoring, reporting, or recordkeeping requirements in the permit;
4. (4) Require or change a case-by-case determination of an emission limitation or other standard, or a source-specific determination for temporary sources of ambient impacts, or a visibility or increment analysis;
5. (5) Involve an increase in regulated air pollutant emissions that cannot be processed under minor permit modification procedures;

6. (6)

   1. (A) Seek to establish or change a permit term or condition for which there is no corresponding underlying applicable requirement and that the source has assumed to avoid an applicable requirement to which the source would otherwise be subject.

   2. (B) Such terms and conditions include:

      1. (i) A federally enforceable emissions cap assumed to avoid classification as a modification under any provision of Title I; and
      2. (ii) An alternative emissions limit approved pursuant to regulations promulgated under Section 112(i)(5) of the Act.