Section 204.800  Applicability

a)         The requirements of this Part apply to the construction of any new major stationary source (as defined in Section 204.510) or any project at an existing major stationary source in an area designated as attainment or unclassifiable under section 107(d)(1)(A)(ii) or (iii) of the CAA (42 USC 7407(d)(1)(A)(ii) or (iii)).

b)         The requirements of Sections 204.810, 204.820, 204.830, 204.840, 204.850, 204.1100, 204.1110, 204.1120, 204.1130, 204.1140, and 204.1200 apply to the construction of any new major stationary source or the major modification of any existing major stationary source, except as this Part otherwise provides.

c)         No new major stationary source or major modification to which the requirements of Sections 204.810, 204.820, 204.830, 204.840, 204.850, 204.1100, 204.1110, 204.1120, 204.1130, 204.1140, and 204.1200 apply shall begin actual construction without a permit that states that the major stationary source or major modification will meet those requirements.  The Agency has authority to issue any such permit.

d)         The requirements of the program will be applied in accordance with the principles set out in this subsection (d).

1)         Except as otherwise provided in subsection (f), and consistent with the definition of major modification contained in Section 204.490, a project is a major modification for a regulated NSR pollutant if it causes two types of emissions increases: a significant emissions increase (as defined in Section 204.670) and a significant net emissions increase (as defined in Sections 204.550 and 204.660).  The project is not a major modification if it does not cause a significant emissions increase.  If the project causes a significant emissions increase, then the project is a major modification only if it also results in a significant net emissions increase.

2)         The procedure for calculating (before beginning actual construction) whether a significant emissions increase (i.e., the first step of the process) will occur depends upon the type or types of emissions units involved in the project, according to subsections (d)(3) through (d)(5).  The procedure for calculating (before beginning actual construction) whether a significant net emissions increase will occur at the major stationary source (i.e., the second step of the process) is contained in the definition in Section 204.550.  Regardless of any such preconstruction projections, a major modification results if the project causes a significant emissions increase and a significant net emissions increase.

3)         Actual-to-Projected-Actual Applicability Test for Projects That Only Involve Existing Emissions Units.  A significant emissions increase of a regulated NSR pollutant is projected to occur if the sum of the difference between the projected actual emissions (as defined in Section 204.600) and the baseline actual emissions (as defined in Section 204.240(a) and (b)), for each existing emissions unit, equals or exceeds the significant amount for that pollutant (as defined in Section 204.660).

4)         Actual-to-Potential Test for Projects That Only Involve Construction of a New Emissions Unit or Units.  A significant emissions increase of a regulated NSR pollutant is projected to occur if the sum of the difference between the potential to emit (as defined in Section 204.560) from each new emissions unit following completion of the project and the baseline actual emissions (as defined in Section 204.240(c)) of these units before the project equals or exceeds the significant amount for that pollutant (as defined in Section 204.660).

5)         Hybrid Test for Projects That Involve Multiple Types of Emissions Unit or Units.  A significant emissions increase of a regulated NSR pollutant is projected to occur if the sum of the emissions increases for each emissions unit, using the method specified in subsections (d)(3) and (d)(4) as applicable with respect to each emissions unit, for each type of emissions unit equals or exceeds the significant amount for that pollutant (as defined in Section 204.660).

e)         Except as otherwise provided in Section 204.1400(f)(2), the provisions of Section 204.1400 apply with respect to any regulated NSR pollutant emitted from projects involving existing emissions units at a major stationary source (other than projects at a source with a PAL) in circumstances in which there is a reasonable possibility, within the meaning of Section 204.1400(f), that a project that is not a part of a major modification may result in a significant emissions increase of such pollutant, and the owner or operator elects to use the method specified in Section 204.600(b) for calculating projected actual emissions.

f)         For any major stationary source for a PAL for a regulated NSR pollutant, the major stationary source shall comply with Subpart K.