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Lead in Air

SIP Toolkit - New Source Review (NSR) Program and the Prevention of Significant Deterioration (PSD)

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Stationary sources that emit lead are currently subject to regulation under existing requirements for the preconstruction review and approval of new and modified stationary sources. The existing requirements, referred to collectively as the New Source Review (NSR) program, require all major and certain minor stationary sources of any air pollutant for which there is a NAAQS to undergo review and approval prior to the commencement of construction. The NSR program is composed of three different permit programs:

  • Prevention of Significant Deterioration (PSD)
  • Nonattainment NSR
  • Minor NSR

The PSD program and nonattainment NSR programs, contained in parts C and D, respectively, of Title I of the CAA, are often referred to as the major NSR program because these programs regulate only major sources. The PSD program applies when a major source, that is located in an area that is designated as attainment or unclassifiable for any criteria pollutant, is constructed, or undergoes a major modification. The nonattainment NSR program applies when a major source of a criteria pollutant that is located in an area that is designated as nonattainment for that pollutant is constructed or undergoes a major modification. The minor NSR program addresses both major and minor sources that undergo construction or modification activities that do not qualify as major, and it applies regardless of the designation of the area in which a source is located. The EPA rules addressing these regulations can be found at 40 CFR 51.160-164, 51.165-166, 52.21, 52.24, and part 51, appendix S.

States containing areas designated as nonattainment for the lead NAAQS must submit SIPs that address the requirements of nonattainment NSR.  Areas designated attainment must submit Infrastructure SIPs that address the requirements of PSD.  Minor NSR programs must meet the statutory requirements in section 110(a)(2)(C) of the CAA which requires ‘‘. . . regulation of the modification and construction of any stationary source . . . as necessary to assure that the [NAAQS] are achieved.’’

The major source threshold under the PSD program is generally either 100 or 250 tons per year (tpy) of any regulated NSR pollutant, depending upon whether the source is included within one of the categories of sources listed in the applicable PSD regulations (40 CFR 51.166(b)(1)(i)(a) or 52.21(b)(1)(i)(a)). The major source threshold for Lead under the nonattainment NSR program is 100 tpy for all source categories. Accordingly, the nonattainment NSR program for Lead applies when any major source of Lead located in an area designated nonattainment for Lead is constructed, or undergoes a major modification. Under both programs, a major modification is a project at a major stationary source that results in a significant emissions increase and a significant net emissions increase, where “significant” for Lead emissions is defined as 0.6 tpy.

  • The PSD requirements include but are not limited to the following:
  • Installation of Best Available Control Technology (BACT)
  • Air quality monitoring and modeling analyses to ensure that a project’s emissions will not cause or contribute to a violation of any NAAQS
  • Notification of Federal Land Manager of nearby Class I areas
  • Public comment on a permit.

Nonattainment NSR requirements include but are not limited to:

  • Installation of Lowest Achievable Emissions Rate (LAER) control technology
  • Offsetting new emissions with creditable emissions reductions
  • A certification that all major sources owned and operated in the state by the same owner are in compliance with all applicable requirements under the CAA
  • An alternatives analysis demonstrating that the benefits of the proposed source significantly outweigh the environmental and social costs imposed as a result of its location, construction, or modification
  • Public comment on a permit.

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