(a) Does this program apply to me? The requirements of this program apply to you as set out in paragraphs (a)(1) through (4) of this section.

(1) New and modified sources. The applicability of the preconstruction review requirements of this program is determined individually for each regulated NSR pollutant that would be emitted by your new or modified source. For each such pollutant, determine applicability as set out in the relevant paragraph (a)(1)(i) or (ii) of this section.

(i) New source. Use the following steps to determine applicability for each regulated NSR pollutant.

(A) Step 1. Determine whether your proposed source's potential to emit the pollutant that you are evaluating is subject to review under the applicable major NSR program (that is, under §52.21 of this chapter, under the Federal major NSR program for nonattainment areas in Indian country at §§49.166 through 49.175 or under a program approved by the Administrator pursuant to §51.165 or §51.166 of this chapter). If not, go to Step 2 (paragraph (a)(1)(i)(B) of this section).

(B) Step 2. Determine whether your proposed source's potential to emit for the pollutant that you are evaluating, (including fugitive emissions, to the extent they are quantifiable, only if the source belongs to one of the source categories listed pursuant to section 302(j) of the Act), is equal to or greater than the corresponding minor NSR threshold in Table 1 of this section. If it is, then you are subject to the pre-construction requirements of this program for that pollutant, except that sources in the oil and natural gas production and natural gas processing segments of the oil and natural gas sector shall instead comply with the requirements of the Federal Implementation Plan at §§49.101 through 49.105, unless you opt-out of the Federal Implementation Plan pursuant to §49.101(b)(2) in which case you are subject to the pre-construction requirements of this program for that pollutant or are required by the EPA to obtain a minor source permit pursuant to §49.101(b)(3). If it is not, then proceed to Step 3 (paragraph (a)(1)(ii)(C) of this section).

(ii) Modification at an existing source. Use the following steps to determine applicability for each regulated NSR pollutant.

(A) Step 1. For the pollutant being evaluated, determine whether your proposed modification is subject to review under the applicable major NSR program. If the modification at your existing major source does not qualify as a major modification under that program based on the actual-to-projected-actual test, it is considered a minor modification and is subject to the minor NSR program requirements, if the net emissions increase from the actual-to-projected-actual test is equal to or exceeds the minor NSR threshold listed in Table 1 of this section. For a modification at your existing minor source go to Step 2 (paragraph (a)(1)(ii)(B) of this section).

(B) Step 2. Determine whether the increase in allowable emissions from the proposed modification (calculated using the procedures of paragraph (b) of this section) would be equal to or greater than the minor NSR threshold in Table 1 of this section for the pollutant that you are evaluating. If it is, then you are subject to the pre-construction requirements of this program for that pollutant, except oil and natural gas production and natural gas processing sources shall instead comply with the requirements of the Federal Implementation Plan at §§49.101 through 49.105, unless you opt-out of the Federal Implementation Plan pursuant to §49.101(b)(2) in which case you are subject to the pre-construction requirements of this program for that pollutant or are required by the EPA to obtain a minor source permit pursuant to §49.101(b)(3). If it is not, then proceed to Step 3 (paragraph (a)(1)(ii)(C) of this section).

(C) Step 3. If any of the emissions units affected by your proposed modification result in an increase in an annual allowable emissions limit for the pollutant that you are evaluating, the proposed modification is subject to paragraph (a)(2) of this section. If not, your proposed modification is not subject to this program.

(2) Increase in an emissions unit's annual allowable emissions limit. If you propose a physical or operational change at your minor or major source that would increase an emissions unit's allowable emissions of a regulated NSR pollutant above its existing annual allowable emissions limit, you must obtain a permit revision to reflect the increase in the limit prior to making the change. For a physical or operational change that is not otherwise subject to review under major NSR or under this program, such increase in the annual allowable emissions limit may be accomplished through an administrative permit revision as provided in §49.159(f).

(3) Synthetic minor source permits.

(i) If you own or operate an existing major source and you wish to obtain a synthetic minor source permit pursuant to §49.158 to establish a synthetic minor source and/or a synthetic minor HAP source, you may submit a synthetic minor source permit application on or after August 30, 2011. However, if your permit application for a synthetic minor source and/or synthetic minor HAP source pursuant to the FIPs for reservations in Idaho, Oregon and Washington has been determined complete prior to August 30, 2011, you do not need to apply for a synthetic minor source permit under this program.

(ii) If you wish to begin construction of a new synthetic minor source and/or a new synthetic minor HAP source or a modification at an existing synthetic minor source and/or synthetic minor HAP source, on or after August 30, 2011, you must obtain a permit pursuant to §49.158 prior to beginning construction.

(iii) If you own or operate a synthetic minor source or synthetic minor HAP source that was established prior to the effective date of this rule (that is, prior to August 30, 2011) pursuant to the FIPs applicable to the Indian reservations in Idaho, Oregon and Washington or under an EPA-approved rule or permit program limiting potential to emit, you do not need to take any action under this program unless you propose a modification for this existing synthetic minor source and/or synthetic minor HAP source on or after August 30, 2011. For these modifications, you need to obtain a permit pursuant to §49.158 prior to beginning construction.

(iv) If you own or operate a synthetic minor source or synthetic minor HAP source that was established prior to the effective date of this rule (that is, prior to August 30, 2011) through a permit with enforceable emissions limitations issued pursuant to the operating permit program in part 71 of this chapter, the reviewing authority has the discretion to require you to apply for a synthetic minor source permit under §49.158 of this program by September 4, 2012 or at the time of part 71 permit renewal or allow you to maintain synthetic minor status through your part 71 permit.

(v) For all other synthetic minor sources or synthetic minor HAP sources that obtained synthetic minor status or synthetic minor source permits through a mechanism other than those described in paragraphs (a)(3)(iii) and (iv) of this section, you must submit an application for a synthetic minor source permit under this program by September 4, 2012 under §49.158.

(4) Case-by-case maximum achievable control technology (MACT) determinations. If you propose to construct or reconstruct a major source of HAPs such that you are subject to a case-by-case MACT determination under section 112(g)(2) of the Act, you may elect to have this determination approved under the provisions of this program (other options for such determinations include a title V permit action or a Notice of MACT Approval under §63.43 of this chapter). If you elect this option, you still must comply with the requirements of §63.43 of this chapter that apply to all case-by-case MACT determinations.

(b) How do I determine the increase in allowable emissions from a physical or operational change at my source? Determine the resulting increase in allowable emissions in tons per year (tpy) of each regulated NSR pollutant after considering all increases from the change. A physical or operational change may involve one or more emissions units. The total increase in allowable emissions resulting from your proposed change, including fugitive emissions, to the extent they are quantifiable, only if your source belongs to one of the source categories listed pursuant to section 302(j) of the Act, would be the sum of the following:

(1) For each new emissions unit that is to be added, the emissions increase would be the potential to emit of the emissions unit.

(2) For each emissions unit with an allowable emissions limit that is to be changed or replaced, the emissions increase would be the allowable emissions of the emissions unit after the change or replacement minus the allowable emissions prior to the change or replacement. However, this may not be a negative value. If the allowable emissions of an emissions unit would be reduced as a result of the change or replacement, use zero in the calculation.

(3) For each unpermitted emissions unit (a unit without any enforceable permit conditions) that is to be changed or replaced, the emissions increase is the allowable emissions of the emissions unit after the change or replacement minus the potential to emit prior to the change or replacement. However, this may not be a negative value. If an emissions unit's post-change allowable emissions would be less than its pre-change potential to emit, use zero in the calculation.

(c) What emissions units and activities are exempt from this program? At a source that is otherwise subject to this program, this program does not apply to the following emissions units and activities that are listed in paragraphs (c)(1) through (12) of this section:

(1) Mobile sources.

(2) Ventilating units for comfort that do not exhaust air pollutants into the ambient air from any manufacturing or other industrial processes

(3) Cooking of food, except for wholesale businesses that both cook and sell cooked food.

(4) Consumer use of office equipment and products.

(5) Janitorial services and consumer use of janitorial products.

(6) Internal combustion engines used for landscaping purposes.

(7) Bench scale laboratory activities, except for laboratory fume hoods or vents.

(8) Single family residences and residential buildings with four or fewer dwelling units.

(9) Emergency generators, designed solely for the purpose of providing electrical power during power outages:

(i) In nonattainment areas classified as serious or lower, the total maximum manufacturer's site-rated horsepower of all units shall be below 500;

(ii) In attainment areas, the total maximum manufacturer's site-rated horsepower of all units shall be below 1,000.

(10) Stationary internal combustion engines with a manufacturer's site-rated horsepower of less than 50.

(11) Furnaces or boilers used for space heating that use only gaseous fuel, with a total maximum heat input (i.e., from all units combined) of:

(i) In nonattainment areas classified as Serious or lower, 5 million British thermal units per hour (MMBtu/hr) or less;

(ii) In nonattainment areas classified as Severe or Extreme, 2 million British thermal units per hour (MMBtu/hr) or less;

(iii) In attainment areas, 10 MMBtu/hr or less.

(12) Air conditioning units used for human comfort that do not exhaust air pollutants in the atmosphere from any manufacturing or other industrial processes.

[76 FR 38788, July 1, 2011, as amended at 79 FR 31044, May 30, 2014; 81 FR 35980, June 3, 2016]