(1) Any new major stationary source located anywhere in a nonattainment area designated under section 107 (d)(1)(A)(i) of the Federal Clean Air Act, that is major for the pollutant for which the area is designated nonattainment is subject to the permitting requirements of WAC 173-400-830 through 173-400-850. Any major modification of an existing major stationary source that is major for the pollutant for which the area is designated nonattainment and is located anywhere in a nonattainment area designated under section 107 (d)(1)(A)(i) of the Federal Clean Air Act, and that has a significant net emissions increase of the pollutant for which the area is designated nonattainment is subject to the permitting requirements of WAC 173-400-830 through 173-400-850. A modification to an existing major stationary source must use the following procedures to determine if the modification would result in a significant net emissions increase of the nonattainment pollutant.

(2) Except as otherwise provided in subsection (4) of this section, and consistent with the definition of major modification, a project is a major modification for a regulated NSR pollutant if it causes two types of emissions increases - A significant emissions increase, and a significant net emissions increase. 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.

(3) 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 of emissions units being modified, according to (a) through (c) of this subsection. For these calculations, fugitive emissions (to the extent quantifiable) are included only if the emissions unit is part of one of the source categories listed in the definition of major stationary source contained in WAC 173-400-810 (14)(e) or if the emissions unit is located at a major stationary source that belongs to one of the listed source categories. Fugitive emissions are not included for those emissions units located at a facility whose primary activity is not represented by one of the source categories listed in the definition of major stationary source contained in WAC 173-400-810 (14)(e) and that are not, by themselves, part of a listed source category. 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 of net emission increase. Regardless of any such preconstruction projections, a major modification results if the project causes a significant emissions increase and a significant net emissions increase.

(a) 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 and the baseline actual emissions, for each existing emissions unit, equals or exceeds the significant amount for that pollutant.

(b) Actual-to-potential test for projects that only involve construction of a new emissions unit(s). A significant emissions increase of a regulated NSR pollutant is projected to occur if the sum of the difference between the potential to emit from each new emissions unit following completion of the project and the baseline actual emissions of these units before the project equals or exceeds the significant amount for that pollutant.

(c) Hybrid test for projects that involve multiple types of emissions 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 (a) and (b) of this subsection as applicable with respect to each emissions unit, for each type of emissions unit equals or exceeds the significant amount for that pollutant.

(4) Any major stationary source which has a PAL for a regulated NSR pollutant shall comply with requirements in WAC 173-400-850.

(5) The following specific provisions apply with respect to any regulated NSR pollutant emitted from projects at existing emissions units at a major stationary source (other than projects at a source with a PAL) in circumstances where there is a reasonable possibility 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 the definition of projected actual emissions contained in WAC 173-400-810 (23)(b)(i) through (iii) for calculating projected actual emissions.

(a) Before beginning actual construction of the project, the owner or operator shall document, and maintain a record of the following information:

(i) A description of the project;

(ii) Identification of the emissions unit(s) whose emissions of a regulated NSR pollutant could be affected by the project; and

(iii) A description of the applicability test used to determine that the project is not a major modification for any regulated NSR pollutant, including the baseline actual emissions, the projected actual emissions, the amount of emissions excluded under the definition of projected actual emissions contained in WAC 173-400-810 (23)(b)(iii) and an explanation for why such amount was excluded, and any netting calculations, if applicable.

(b) Before beginning actual construction, the owner or operator shall provide a copy of the information set out in (a) of this subsection to the permitting authority. This information may be submitted in conjunction with any NOC application required under the provisions of WAC 173-400-110. Nothing in this subsection shall be construed to require the owner or operator of such a unit to obtain any determination from the permitting authority before beginning actual construction.

(c) The owner or operator shall monitor the emissions of any regulated NSR pollutant that could increase as a result of the project and that is emitted by any emissions units identified in (a)(ii) of this subsection; and calculate and maintain a record of the annual emissions, in tons per year on a calendar year basis, for a period of five years following resumption of regular operations after the change, or for a period of ten years following resumption of regular operations after the change if the project increases the design capacity or potential to emit of that regulated NSR pollutant at such emissions unit.

(d) The owner or operator shall submit a report to the permitting authority within sixty days after the end of each year during which records must be generated under (c) of this subsection setting out the unit's annual emissions, as monitored pursuant to (c) of this subsection, during the year that preceded submission of the report.

(e) The owner or operator shall submit a report to the permitting authority if the annual emissions, in tons per year, from the project identified in (a) of this subsection, exceed the baseline actual emissions (as documented and maintained pursuant to (a)(iii) of this subsection), by a significant amount (as defined in the definition of significant) for that regulated NSR pollutant, and if such emissions differ from the preconstruction projection as documented and maintained pursuant to (a)(iii) of this subsection. Such report shall be submitted to the permitting authority within sixty days after the end of such year. The report shall contain the following:

(i) The name, address and telephone number of the major stationary source;

(ii) The annual emissions as calculated pursuant to (d) of this subsection; and

(iii) Any other information that the owner or operator wishes to include in the report (e.g., an explanation as to why the emissions differ from the preconstruction projection).

(f) A "reasonable possibility" under this subsection occurs when the owner or operator calculates the project to result in either:

(i) A projected actual emissions increase of at least fifty percent of the amount that is a "significant emissions increase," (without reference to the amount that is a significant net emissions increase), for the regulated NSR pollutant; or

(ii) A projected actual emissions increase that, added to the amount of emissions excluded under the definition of projected actual emissions sums to at least fifty percent of the amount that is a "significant emissions increase," (without reference to the amount that is a significant net emissions increase), for the regulated NSR pollutant. For a project for which a reasonable possibility occurs only within the meaning of (f)(ii) of this subsection, and not also within the meaning of (f)(i) of this subsection, then (c) through (f) of this subsection does not apply to the project.

(6) For projects not required to submit the above information to the permitting authority as part of a notice of construction application, the owner or operator of the source shall make the information required to be documented and maintained pursuant to subsection (5) of this section available for review upon a request for inspection by the permitting authority or the general public pursuant to the requirements contained in chapter 173-401 WAC.