Limited Maintenance Plan for the Charlotte-Gastonia-Rock Hill Maintenance Area for the 1997 8-Hour Ozone NAAQS

Final – December 9, 2021

On December 9, 2021, the Division of Air Quality (DAQ) submitted the final State Implementation Plan (SIP) revision for the “Limited Maintenance Plan (LMP) for the Charlotte-Gastonia-Rock Hill Maintenance Area for the 1997 8-Hour Ozone National Ambient Air Quality Standard (NAAQS))” for approval by the U.S. Environmental Protection Agency (EPA). The DAQ  prepared this LMP for the Charlotte-Gastonia-Rock Hill maintenance area for the 1997 8-hour ozone NAAQS to comply with the D.C. Circuit decision that vacated EPA’s interpretation that the second maintenance plans were not required for “orphan maintenance areas” (i.e., areas that had been redesignated to attainment for the 1997 ozone NAAQS (maintenance areas) and designated attainment for the 2008 ozone NAAQS) (South Coast, 882 F.3d 1138 (D.C. Cir. 2018)).

The DAQ prepared the LMP following EPA guidance to fulfill the requirements of Clean Air Act Section 175A(b) with respect to the second maintenance plan period for the maintenance area. The LMP covers the last 10 years of the 20-year maintenance period from January 3, 2024 through January 2, 2034.

DEQ Submittals:

EPA Actions:

  • Final Rule: Air Plan Approval; North Carolina; Charlotte-Gastonia-Rock Hill Area Limited Maintenance Plan for the 1997 8-Hour Ozone NAAQS (88 FR 2245, January 13, 2023)

  • Proposed Rule: Air Plan Approval; North Carolina; Charlotte-Gastonia-Rock Hill Area Limited Maintenance Plan for the 1997 8-Hour Ozone NAAQS (87 FR 70758, November 21, 2022)

Pre-Hearing Draft – October 27, 2021

The pre-hearing draft of the State Implementation Plan (SIP) revision for the “Limited Maintenance Plan (LMP) for the Charlotte-Gastonia-Rock Hill Maintenance Area for the 1997 8-Hour Ozone National Ambient Air Quality Standard (NAAQS)” is available for review and public comment.  The North Carolina Division of Air Quality (DAQ) prepared this LMP for the Charlotte-Gastonia-Rock Hill maintenance area for the 1997 8-hour ozone NAAQS to comply with the D.C. Circuit decision that vacated EPA’s interpretation that the second maintenance plans were not required for “orphan maintenance areas” (i.e., areas that had been redesignated to attainment for the 1997 ozone NAAQS (maintenance areas) and designated attainment for the 2008 8-hour ozone NAAQS) (South Coast, 882 F.3d 1138 (D.C. Cir. 2018)).  The LMP covers the last 10 years of the 20-year maintenance period from January 3, 2024, through January 2, 2034. 

The DAQ prepared the LMP following EPA guidance to fulfill the requirements of Clean Air Act Section 175A(b) with respect to the second maintenance plan period for each of the three areas. The DAQ intends to submit a final version of this LMP to EPA for incorporation into North Carolina’s SIP after considering relevant public comments.

DEQ Submittals:

The comment period duration is from Wednesday, October 27, 2021, through Tuesday, November 30, 2021. Written requests for a public hearing must follow the procedures in the public notice and should be postmarked or submitted electronically no later than Wednesday, November 10, 2021. Please submit comments via any of the methods below:

  • Email:
    daq.publiccomments@ncdenr.gov
    (please type “Metrolina LMP 1997 Ozone NAAQS” in the subject line)
     
  • Postal Mail:
    Tammy Manning
    NC Division of Air Quality
    1641 Mail Service Center
    Raleigh, NC  27699-1641
     
  • Fax:
    (919) 715-0718

Final Supplement to the Redesignation Demonstration and Maintenance Plan for 1997 8-hour Ozone - February 2013

The final "Supplement for Redesignation Demonstration and Maintenance Plan for the Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-hour Ozone Nonattainment Area", referred to as the Metrolina area, was submitted to the United States Environmental Protection Agency on March 28, 2013. The narrative documents that the Metrolina area has attained the 1997 8-hour ozone National Ambient Air Quality Standard, fulfilling requirements of Section 175A(b) of the Federal Clean Air Act as amended.

This supplement covers four additions and/or changes to the original redesignation demonstration and maintenance plan. The first is the addition of future year 2025 emissions inventory for point sources, area sources, on-road mobile sources, and non-road mobile sources. The second is the updating of the ambient air quality monitoring data for years 2011 and 2012, which were not available at the time the original document was submitted. The third is the accounting of point source emissions for facilities that have recently rescinded their operating permits. Emissions for these sources are included in this supplement because some of these plants may resume operation when the economy improves. The final change to the supplement is the use of more recent fuel properties data to calculate non-road emissions.

The transmittal letter, narrative, and appendices are available through the links found below:

DEQ Submittals:

EPA Actions:

  • Final Rule: Approval and Promulgation of Implementation Plans and Designation of Areas; North Carolina; Redesignation of the Charlotte Gastonia-Rock Hill, 1997 8-Hour Ozone Moderate Nonattainment Area to Attainment (78 FR 72036, December 2, 2013)
  • Proposed Rule: Approval and Promulgation of Implementation Plans and Designation of Areas; North Carolina; Redesignation of the Charlotte Gastonia-Rock Hill, 1997 8-Hour Ozone Moderate Nonattainment Area to Attainment (78 FR 45152,July 26, 2013)

Please direct any further questions or comments concerning this SIP submittal to the Planning Section Chief.

EPA Approval and Promulgation of Implementation Plans and Designation of Areas for Air Quality Planning Purposes; North Carolina; Redesignation of the Charlotte 1997 8-Hour Ozone Moderate Nonattainment Area to Attainment (78 FR 72036-72040)

Redesignation Demonstration and Maintenance Plan for 1997 8-hour Ozone - November 2011

The final "Redesignation Demonstration and Maintenance Plan for the Charlotte-Gastonia-Rock Hill, NC-SC 1997 8-Hour Ozone Nonattainment Area" was submitted to the United States Environmental Protection Agency on November 3, 2011. The narrative documents that the Metrolina area has attained the 1997 8-hour ozone national ambient air quality standard, fulfilling requirements of Section 175A(b) of the Federal Clean Air Act as amended. The transmittal letter, narrative, and appendices are available through the links found below:

DEQ Submittals:

South Carolina's Redesignation Demonstration & Maintenance Plan for their portion of the Metrolina nonattainment area was submitted to the USEPA on June 2, 2011 and is available upon request.

Please direct any further questions or comments concerning this SIP submittal to the Planning Section Chief.

 Reasonable Further Progress Demonstration Plan for 1997 8-hour Ozone - November 2009

 The final "North Carolina Reasonable Further Progress (RFP) Demonstration State Implementation Plan (SIP) for the North Carolina portion of the Charlotte-Gastonia-Rock Hill, NC-SC 8 Hour Ozone Nonattainment Area" (referred to as the Metrolina area) package was submitted to the United States Environmental Protection Agency (USEPA) on November 30, 2009. The narrative documents that the Metrolina area demonstrates reasonable further progress, fulfilling requirements of Section 172(c) of the Federal Clean Air Act as amended for the 1997 8 hour ozone national ambient air quality standard.

A public comment period was open from October 12, 2009 through November 13, 2009. A public hearing was held on Friday, November 13, 2009, in Charlotte, North Carolina. The comments received during the public comment period and the hearing officer's report are included in Appendix H.

The transmittal letter, narrative, and appendices are available through the links found below:

DEQ Submittals:

EPA Actions:

  • Direct Final Rule: EPA Approval and Promulgation of Implementation Plans; North Carolina Portion of the Charlotte-Gastonia-Rock Hill, North Carolina-South Carolina 1997 8-Hour Ozone Nonattainment Area; Reasonable Further Progress Plan (77 FR 62159, October 12, 2012)
  • Proposed Rule: EPA Approval and Promulgation of Implementation Plans; North Carolina Portion of the Charlotte-Gastonia-Rock Hill, North Carolina-South Carolina 1997 8-Hour Ozone Nonattainment Area; Reasonable Further Progress Plan (77 FR 62200, October 12, 2012) 

Please direct any further questions or comments concerning this SIP submittal to the Planning Section Chief.

EPA Approval and Promulgation of Implementation Plans; North Carolina Portion of the Charlotte-Gastonia-Rock Hill, North Carolina-South Carolina 1997 8-Hour Ozone Nonattainment Area; Reasonable Further Progress Plan (77 FR 62159-62166)

Attainment Demonstration Submittal for 1997 8-hour Ozone - June 2007

On June 15, 2007, the final "Attainment Demonstration for the Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Nonattainment Area State Implementation Plan (SIP)" was submitted to the United States Environmental Protection Agency (USEPA) and was posted to the NC Division of Air Quality (NCDAQ) web site. The transmittal letter, narrative, and appendices from that posting are available through the links found below:

DEQ Submittals:

This submittal documented that the Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Nonattainment Area (referred to as the Metrolina area) would attain the 1997 8-hour ozone national ambient air quality standard (NAAQS), fulfilling requirements of Section 172(c), 182(c), and 182(b) of the Federal Clean Air Act (CAA) as amended. Additionally, a public hearing regarding this SIP was held at 3:00 PM on April 26, 2007 at the Charlotte Mecklenburg Government Center, 600 East Fourth Street, Charlotte, NC 28202.

Mr. James Palmer, USEPA Region 4 Regional Administrator, notified the North Carolina Department of Environment and Natural Resources (NCDENR) on November 17, 2008 of the USEPA intent to disapprove this attainment demonstration based on air quality measurements from the summers of 2007 and 2008. In the USEPA's opinion, the Metrolina area would not be able to demonstrate attainment of the NAAQS by the end of 2009 and also would not meet the CAA requirements for a one-year extension of the attainment date. Mr. Palmer went on to offer North Carolina the opportunity to voluntarily request to reclassify the North Carolina portion of the Metrolina area to a higher (serious) classification of nonattainment. If approved, this action would establish a new attainment date and require a revision of the attainment demonstration SIP to reflect the additional requirements based on the area's new classification.

On December 19, 2008, the NCDENR withdrew the Metrolina attainment demonstration SIP, citing concerns with the options that the USEPA had offered in their November 17, 2008, letter and the belief that it was possible for the region to qualify for the one-year extension of the attainment date. In the withdrawal letter, the NCDENR committed to revise the modeling and submit an updated SIP by the end of November 2009.

In January 2009, the NCDAQ notified the transportation partners of its intention to re-model the attainment demonstration and requested revised data for 2011, which at that time was believed to be the projected attainment year given the 2007 and 2008 ambient data. The USEPA was copied on this correspondence to keep them informed of the NCDAQ's intentions and progress on the re-modeling effort. Additionally, there were monthly conformity calls with the Metrolina transportation partners, monthly calls for the statewide interagency consultation meetings, and monthly calls between the USEPA Region 4 SIP staff and the NCDAQ Planning staff, all of which had updates on the modeling progress.

On August 14, 2009, the NCDAQ shared an internal draft of the revised attainment demonstration with the USEPA and the transportation partners for a 30-day comment period. The NCDAQ learned at the end of the comment period that the USEPA had issues with the attainment year being 2011. After several weeks of discussions within the USEPA, the NCDAQ was given two options on November 4, 2009:

Option 1 - The State could re-submit the original attainment demonstration and then submit supplemental information. The supplemental information would include the 2009 ambient air quality data showing the area qualifies for a one-year extension and the 2011 modeling as weight of evidence that the Metrolina region would attain the standard by June 15, 2011.
Option 2 - The State could use the original 2009 modeling and the revised 2011 modeling to develop a plan to demonstrate the area would attain the standard by June 15, 2011.


The NCDAQ chose Option 1, to re-submit the original attainment demonstration SIP. On, November 12, 2009, the NCDAQ re-submitted the original June 2007 Attainment Demonstration for the Charlotte-Gastonia-Rock Hill, NC-SC 8-Hour Ozone Nonattainment Area SIP (referenced above) to the USEPA. The NCDAQ is now in the process of coordinating with the USEPA, Region 4 staff as to what will be needed in the supplemental information and is working to submit this necessary information as quickly as possible. Once developed, this supplemental documentation will go through the public hearing process prior to submittal to the USEPA.

The various letters exchanged between the USEPA and the NCDENR/NCDAQ and the re-submittal transmittal letter are available through the links found below:

For any questions or additional information, please send an e-mail to the Planning Section Chief with "Metrolina Attainment Demonstration" in the subject line.