Section 50. Definitions

A. For the purpose of applying this part in the context of the Regulations for the Control and Abatement of Air Pollution and related uses, the words or terms shall have the meanings given them in 9VAC5-80-1615 (Definitions), except for the terms defined in subsection C of this section.

B. Unless otherwise required by context, all terms not defined herein shall have the meanings given them in 9VAC5-10 (General Definitions) or 9VAC5-80-5 (Definitions), or commonly ascribed to them by recognized authorities, in that order of priority.

C. Terms defined.

"Actuals PAL" means (i) for major stationary sources, a PAL based on the baseline actual emissions of all emissions units at the source that emit or have the potential to emit the PAL pollutant or (ii) for GHG-only sources, a PAL based on the baseline actual emissions of all emissions units at the source, that emit or have the potential to emit GHGs.

"Allowable emissions" means the emissions rate of a stationary source calculated using the maximum rated capacity of the source (unless the source is subject to federally enforceable limits that restrict the operating rate or hours of operation, or both) and the most stringent of the following:

1. The allowable emissions for any emissions unit as calculated considering any emission limitations that are enforceable as a practical matter on the emissions unit's potential to emit; or

2. An emissions unit's potential to emit.

"Baseline actual emissions for a GHG PAL" means the average rate, in tons per year CO₂e or tons per year GHG, as applicable, at which the emissions unit actually emitted GHGs during any consecutive 24-month period selected by the owner within the 10-year period immediately preceding either the date the owner begins actual construction of the project or the date a complete permit application is received by the board for a permit required under this part. For any existing electric utility steam generating unit, baseline actual emissions for a GHG PAL means the average rate, in tons per year CO₂e or tons per year GHG, as applicable, at which the emissions unit actually emitted the GHGs during any consecutive 24-month period selected by the owner within the five-year period immediately preceding the date the owner begins actual construction of the project, except that the board will allow the use of a different time period upon a determination that it is more representative of normal source operation.

1. The average rate shall include fugitive emissions to the extent quantifiable, and emissions associated with startups, shutdowns, and malfunctions.

2. The average rate shall be adjusted downward to exclude any noncompliant emissions that occurred while the source was operating above an emission limitation that was legally enforceable during the consecutive 24-month period.

3. The average rate shall be adjusted downward to exclude any emissions that would have exceeded an emission limitation with which the stationary source shall currently comply, had such stationary source been required to comply with such limitations during the consecutive 24-month period.

4. The average rate shall not be based on any consecutive 24-month period for which there is inadequate information for determining annual GHG emissions and for adjusting this amount if required by subdivisions 2 and 3 of this definition.

"Emissions unit" means any part of a stationary source that emits or has the potential to emit GHGs. For purposes of 9VAC5-85-55, there are two types of emissions units: (i) a new emissions unit is any emissions unit that is or will be newly constructed and that has existed for less than two years from the date such emissions unit first operated, and (ii) an existing emissions unit is any emissions unit that does not meet the definition of a new emissions unit. A replacement unit is an existing emissions unit.

"GHG-only source" means any existing stationary source that emits or has the potential to emit GHGs in the amount equal to or greater than the amount of GHGs on a mass basis that would be sufficient for a new source to trigger permitting requirements for GHGs under the definition of "major stationary source" and the amount of GHGs on a CO₂e basis that would be sufficient for a new source to trigger permitting requirements for GHGs under the definition of "subject to regulation" at the time the PAL permit is being issued, but does not emit or have the potential to emit any other non-GHG regulated NSR pollutant at or above the applicable major source threshold. A GHG-only source may only obtain a PAL for GHG emissions under 9VAC5-85-55.

"Greenhouse gases" or "GHGs" means the aggregate group of six greenhouse gases: carbon dioxide, nitrous oxide, methane, hydrofluorocarbons, perfluorocarbons, and sulfur hexafluoride.

"Major emissions unit" means (i) for any major stationary source obtaining a GHG PAL issued on a mass basis, a major emissions unit as defined in 9VAC5-80-1615 C or (ii) for a GHG PAL issued on a CO₂e basis, any emissions unit that emits or has the potential to emit equal to or greater than the amount of GHGs on a CO₂e basis that would be sufficient for a new source to trigger permitting requirements under the definition of "subject to regulation" at the time the PAL permit is being issued.

"Major stationary source" means a major stationary source that is defined in and subject to Article 8 (9VAC5-80-1605 et seq.) of 9VAC5-80 (Permits for Stationary Sources) and that meets the definition of "subject to regulation."

"Minor source" means any stationary source that does not meet either (i) the definition of "major stationary source" for any pollutant at the time the PAL is issued or (ii) the definition of "subject to regulation."

"Plantwide applicability limitation" or "PAL" means an emission limitation expressed on a mass basis in tons per year, or expressed in tons per year CO₂e for a CO₂e-based GHG emission limitation, for a pollutant at a major stationary source or GHG-only source, that is enforceable as a practical matter and established sourcewide in accordance with 9VAC5-85-55.

"PAL effective date" generally means the date of issuance of the PAL permit. However, the PAL effective date for an increased PAL is the date any emissions unit that is part of the PAL major modification becomes operational and begins to emit the PAL pollutant.

"PAL effective period" means the period beginning with the PAL effective date and ending 10 years later.

"PAL major modification" means, notwithstanding the definitions for "major modification" and "net emissions increase" as defined in 9VAC5-80-1615 C and the definition of "subject to regulation" of this section, any physical change in or change in the method of operation of the PAL source that causes it to emit the PAL pollutant at a level equal to or greater than the PAL.

"PAL permit" means the major NSR permit, the state operating permit, or the federal operating permit that establishes a PAL for a major stationary source or a GHG-only source.

"PAL pollutant" means the pollutant for which a PAL is established at a major stationary source or a GHG-only source. For a GHG-only source, the only available PAL pollutant is greenhouse gases.

"Potential to emit" means the maximum capacity of a stationary source to emit a pollutant under its physical and operational design. Any physical or operational limitation on the capacity of the source to emit a pollutant, including air pollution control equipment and restrictions on hours of operation or on the type or amount of material combusted, stored, or processed, shall be treated as part of its design if the limitation or the effect it would have on emissions is federally enforceable or enforceable as a practical matter. Secondary emissions do not count in determining the potential to emit of a stationary source. For the purposes of actuals PALs, any physical or operational limitation on the capacity of the source to emit a pollutant, including air pollution control equipment and restrictions on hours of operation or on the type or amount of material combusted, stored, or processed, shall be treated as part of its design only if the limitation or the effect it would have on emissions is federally enforceable or enforceable as a practical matter by the state.

"Regulated NSR pollutant" means:

1. Any pollutant for which an ambient air quality standard has been promulgated and any constituents or precursors for such pollutants identified by the administrator (e.g., volatile organic compounds and NO_X are precursors for ozone);

2. Any pollutant that is subject to any standard promulgated under § 111 of the federal Clean Air Act;

3. Any class I or II substance subject to a standard promulgated under or established by Title VI of the federal Clean Air Act; or

4. Any pollutant that otherwise is subject to regulation under the federal Clean Air Act as defined in the definition of "subject to regulation."

5. Notwithstanding subdivisions 1 through 4 of this definition, the term "regulated NSR pollutant" shall not include any or all hazardous air pollutants either listed in § 112 of the federal Clean Air Act, or added to the list pursuant to § 112(b)(2) of the federal Clean Air Act, and which have not been delisted pursuant to § 112(b)(3) of the federal Clean Air Act, unless the listed hazardous air pollutant is also regulated as a constituent or precursor of a general pollutant listed under § 108 of the federal Clean Air Act.

"Replacement unit" means an emissions unit for which all the following criteria are met. No creditable emission reductions shall be generated from shutting down the existing emissions unit that is replaced.

1. The emissions unit is a reconstructed unit within the meaning of 40 CFR 60.15(b)(1), or the emissions unit completely takes the place of an existing emissions unit.

2. The emissions unit is identical to or functionally equivalent to the replaced emissions unit.

3. The replacement does not change the basic design parameters of the process unit.

4. The replaced emissions unit is permanently removed from the major stationary source, otherwise permanently disabled, or permanently barred from operation by a permit that is enforceable as a practical matter. If the replaced emissions unit is brought back into operation, it shall constitute a new emissions unit.

"Significant emissions unit" means (i) for a GHG PAL issued on a mass basis, an emissions unit that emits or has the potential to emit a PAL pollutant in an amount that is equal to or greater than the significant level for that PAL pollutant, but less than the amount that would qualify the unit as a major emissions unit or (ii) for a GHG PAL issued on a CO₂e basis, any emissions unit that emits or has the potential to emit GHGs on a CO₂e basis in amounts equal to or greater than the amount that would qualify the unit as small emissions unit, but less than the amount that would qualify the unit as a major emissions unit.

"Small emissions unit" means (i) for a GHG PAL issued on a mass basis, an emissions unit that emits or has the potential to emit the PAL pollutant in an amount less than the significant level for that PAL pollutant, as defined in this section or in the federal Clean Air Act, whichever is lower or (ii) for a GHG PAL issued on a CO₂e basis, an emissions unit that emits or has the potential to emit less than the amount of GHGs on a CO₂e basis defined as "significant" for the purposes of subdivision 3 of the definition of "subject to regulation" at the time the PAL permit is being issued.

"Subject to regulation" means, for any air pollutant, that the pollutant is subject to either a provision in the federal Clean Air Act, or a nationally applicable regulation codified by the administrator in Subchapter C of 40 CFR Chapter I, that requires actual control of the quantity of emissions of that pollutant, and that such a control requirement has taken effect and is operative to control, limit or restrict the quantity of emissions of that pollutant released from the regulated activity. The following exceptions shall apply:

1. GHGs shall not be subject to regulation except as provided in subdivisions 4 and 5 of this definition and shall not be subject to regulation if the stationary source maintains its total sourcewide emissions below the GHG PAL level, meets the requirements of 9VAC5-85-55, and complies with the PAL permit containing the GHG PAL. A GHG-only source with a valid CO₂e-based GHG PAL shall be considered to be a minor source for GHG.

2. For purposes of subdivisions 3, 4, and 5 of this definition, the term "tpy CO₂ equivalent emissions (CO₂e)" shall represent an amount of GHGs emitted, and shall be computed as follows:

a. Multiplying the mass amount of emissions (tpy), for each of the six greenhouse gases in the pollutant GHGs, by the gas's associated global warming potential published at Table A-1 to Subpart A of 40 CFR Part 98. For purposes of this subdivision, prior to July 21, 2014, the mass of the greenhouse gas carbon dioxide shall not include carbon dioxide emissions resulting from the combustion or decomposition of nonfossilized and biodegradable organic material originating from plants, animals, or micro-organisms (including products, byproducts, residues, and waste from agriculture, forestry, and related industries as well as the nonfossilized and biodegradable organic fractions of industrial and municipal wastes, including gases and liquids recovered from the decomposition of nonfossilized and biodegradable organic material).

b. Sum the resultant value from subdivision a of this subdivision for each gas to compute a tpy CO₂e.

3. The term "emissions increase" as used in subdivisions 4 and 5 of this definition shall mean that both a significant emissions increase (as calculated using the procedures in 9VAC5-80-1605 G) and a significant net emissions increase (as defined in 9VAC5-80-1615 C) occur. For the pollutant GHGs, an emissions increase shall be based on tpy CO₂e, and shall be calculated assuming the pollutant GHGs is a regulated NSR pollutant, and "significant" is defined as 75,000 tpy CO₂e instead of applying the value in subdivision b of the definition of "significant" in 9VAC5-80-1615 C.

4. Beginning January 2, 2011, the pollutant GHGs is subject to regulation if:

a. The stationary source is a new major stationary source for a regulated NSR pollutant that is not GHGs, and also will emit or will have the potential to emit 75,000 tpy CO₂e or more; or

b. The stationary source is an existing major stationary source for a regulated NSR pollutant that is not GHGs, and also will have an emissions increase of a regulated NSR pollutant, and an emissions increase of 75,000 tpy CO₂e or more.

5. Beginning July 1, 2011, in addition to the provisions in subdivision 4 of this definition, the pollutant GHGs shall also be subject to regulation:

a. At a new stationary source that will emit or have the potential to emit 100,000 tpy CO₂e; or

b. At an existing stationary source that emits or has the potential to emit 100,000 tpy CO₂e, when such stationary source undertakes a physical change or change in the method of operation that will result in an emissions increase of 75,000 tpy CO₂e or more.

Historical Notes

Derived from Volume 27, Issue 03, eff. January 2, 2011; amended, Virginia Register Volume 28, Issue 03, eff. November 9, 2011; Volume 30, Issue 11, eff. March 13, 2014; Volume 31, Issue 22, eff. August 13, 2015.

Statutory Authority

§ 10.1-1308 of the Code of Virginia; Clean Air Act (§§ 110, 112, 165, 173, 182, and Title V); 40 CFR Parts 51, 61, 63, 70, and 72.