Proposed Rule
Air Plan Approval; South Carolina; Minor Source Permit Program Revisions
The full text was pulled automatically from the official source and is not Threadline News reporting; the annotations alongside it are.
Agency
Environmental Protection Agency (EPA).
Action
Proposed rule.
Summary
The U.S. Environmental Protection Agency (EPA or Agency) is proposing to approve changes to South Carolina's State Implementation Plan (SIP) to revise regulations prescribing minor source permit program requirements, including minor new source review (NSR) requirements, in SIP revisions submitted by the State of South Carolina on October 1, 2007, July 18, 2011, August 8, 2014, April 24, 2020, and July 23, 2025. This action is being proposed pursuant to the Clean Air Act (CAA or Act).
Dates
Comments must be received on or before September 18, 2026.
Addresses
Submit your comments, identified by Docket ID No. EPA-R04- OAR-2024-0241 at regulations.gov. Follow the online instructions for submitting comments. Once submitted, comments cannot be edited or removed from Regulations.gov. The EPA may publish any comment received to its public docket. Do not submit electronically any information you consider to be Confidential Business Information (CBI) or other information whose disclosure is restricted by statute. Multimedia submissions (audio, video, etc.) must be accompanied by a written comment. The written comment is considered the official comment and should include discussion of all points you wish to make. The EPA will generally not consider comments or comment contents located outside of the primary submission (i.e., on the web, cloud, or other file sharing system). For additional submission methods, the full EPA public comment policy, information about CBI or multimedia submissions, and general guidance on making effective comments, please visit https://www.epa.gov/dockets/commenting-epa-dockets.
For further information contact
Faith Goddard, Multi-Air Pollutant Coordination Section, Air Planning and Implementation Branch, Air and Radiation Division, U.S. Environmental Protection Agency, Region 4, 61 Forsyth Street SW, Atlanta, Georgia 30303-8960. The telephone number is (404) 562-8757. Ms. Goddard can also be reached via electronic mail at [email protected].
Supplementary information
Notice of proposed rulemaking (NPRM) acronyms and abbreviations. The EPA uses multiple acronyms and terms in this NPRM. While this list may not be exhaustive, to ease the reading of this preamble and for reference purposes, the EPA defines the following terms and acronyms here:
CAA Clean Air Act
CFR Code of Federal Regulations CO Carbon Monoxide EPA Environmental Protection Agency FR Federal Register MMBtu Million British Thermal Units MSA Metropolitan Statistical Area NAAQS National Ambient Air Quality Standard or Standards NEI National Emissions Inventory NOX Nitrogen Oxides NNSR Nonattainment New Source Review NPRM Notice of Proposed Rulemaking NSPS New Source Performance Standards NSR New Source Review PM Particulate Matter PM2.5 Fine PM PM10 Coarse PM PSD Prevention of Significant Deterioration PTE Potential to Emit SIP State Implementation Plan SO2 Sulfur Dioxide TPY Tons Per Year VOC Volatile Organic Compound
Table of Contents
I. Executive Summary A. What action is the EPA taking? B. What is the legal authority and what are the requirements? II. Proposed Action III. Background A. Minor NSR Program Background B. South Carolina's Minor Source Permitting Program C. The EPA's August 17, 2017, and January 21, 2025, Proposals IV. Summary of South Carolina's Submittals V. The EPA's Evaluation of the State's Submittals A. Subparagraph II(B)(2)(h) B. Paragraph II(K)(5) C. South Carolina's CAA Section 110(l) Demonstration 1. CAA Section 110(l) Demonstration--South Carolina's Minor Source Permitting Exemptions 2. CAA Section 110(l) Demonstration--South Carolina's Automatic Exemption Thresholds 3. The EPA's Analysis i. Ozone, NO2, and CO NAAQS 1. Ozone NAAQS 2. NO2 NAAQS 3. CO NAAQS 4. 2020 NOX, VOCs, and CO NEI Data 5. Ozone, NO2, and CO NAAQS Analysis ii. Fine Particulate Matter (PM2.5), SO2, and NO2 NAAQS 1. PM2.5 NAAQS 2. SO2 NAAQS 3. NO2 NAAQS 4. 2020 PM2.5, SO2, and NO2 NEI Data 5. PM2.5, SO2, and NO2 Analysis iii. Coarse Particulate Matter (PM10) NAAQS 1. PM10 NAAQS 2. 2020 PM10 NEI Data 3. PM10 Analysis 4. Summary of the EPA's Findings From South Carolina's CAA Section 110(l) Demonstration VI. Incorporation by Reference VII. Statutory and Executive Order Reviews
A. What action is the EPA taking?
On October 1, 2007, July 18, 2011, August 8, 2014, and April 24, 2020, SC DHEC \1\ submitted SIP revisions to the EPA for approval that include changes to South Carolina's minor source permitting regulations to revise the State's federally approved minor source preconstruction and operating permit program. This federally approved program requires minor stationary sources of air pollutants planning to construct or modify to first obtain a construction permit and then obtain and maintain operating permits in accordance with the South Carolina Code of Regulations Annotated (S.C. Code Ann. Regs.) (hereinafter "Regulation") 61-62.1, Section II, Permit Requirements. The portion of the SIP-approved minor source permitting program covering construction permits is generally referred to as the minor NSR program.\2\
\1\ On July 1, 2024, SC DHEC was restructured into a health agency, the Department of Public Health, and an environmental agency, the Department of Environmental Services (DES). In a letter dated June 20, 2024, South Carolina represented to the EPA that all the functions, powers, and duties of the environmental divisions, offices, and programs of DHEC, including the authority to administer and enforce SIPs, are retained and continued in full force and effect under SC DES. This letter is available in the docket for this proposed rulemaking. In this NPRM, "State," "Department," "SC DHEC," and "SC DES" are interchangeable where applicable. \2\ The portion of the SIP-approved minor source permitting program covering operating permits is also referred to as the federally enforceable state operating permit (FESOP) program.
SC DES subsequently submitted a SIP revision on July 23, 2025, updating references to reflect the restructuring of South Carolina DHEC to the South Carolina Department of Public Health and the South Carolina DES.\3\ As discussed in the July 23, 2025, SIP submittal and in a letter from South Carolina to the EPA Region 4 dated June 20, 2024, all functions, powers, and duties of the environmental divisions, offices, and programs of DHEC are retained and continued in full force and effect under DES. This includes the authority to administer and enforce SIPs. Therefore, the changes within Regulation 61-62.1, Section II, reflecting the restructuring, are merely administrative in nature.
\3\ On May 28, 2026, the EPA proposed to approve administrative changes, reflecting the Department name change, from the July 23, 2025, SIP revision for other regulations, including Regulations 61- 62.1, Definition and General Requirements, Section I; 61-62.3, Air Pollution Episodes; 61-62.4, Hazardous Air Pollution Conditions; 61- 62.5, Standard 4, Emissions from Process Industries; and 61-62.96, Nitrogen Oxides (NOX) Budget Program. See 91 FR 31686.
On May 13, 2026, SC DES submitted supplemental materials, including a letter requesting that the EPA conditionally approve portions of the State's minor source permitting SIP revisions in Regulation 61-62.1 based on a commitment under CAA section 110(k)(4) to adopt and submit corrective revisions to portions of the SIP provisions currently before the EPA no later than one year after the EPA's conditional approval of South Carolina's submissions. Additionally, the supplemental materials included a CAA section 110(l) demonstration to support the corrective changes that the State intended to submit in a corrective SIP revision. The CAA section 110(l) demonstration also applies to a portion of the SIP submittals for which the State did not request conditional approval. Subsequently, on July 21, 2026,\4\ SC DES submitted a letter removing from EPA consideration the subset of provisions in Regulation 61-62.1, Section II, for which the State, in its May 13, 2026, letter, requested conditional approval. That letter supersedes the May 13, 2026, request for conditional approval of those same provisions. Specifically, the July 21, 2026, letter removes from EPA consideration two sentences within subparagraph II(B)(2)(h) \5\ and paragraphs II(B)(3), II(B)(5), and II(B)(6), as submitted through the April 24, 2020, SIP revision. South Carolina states that "the specific text . . . is not before EPA at this time."
\4\ The EPA notes that the Agency received the letter, which is dated July 20, 2026, on July 21, 2026. For consistency, throughout this document we will refer to this as the July 21, 2026, letter. \5\ Specifically, the State requested that EPA not incorporate into subparagraph II(B)(2)(h) the second and third sentences of the revised subparagraph, reading: "Unless otherwise exempt, sources may be exempted under this section at higher emission levels if there is a demonstration that there are no applicable limits or requirements. These applicable requirements include federally applicable limits or requirements."
In this proposed action, the EPA is proposing only to approve the portions of the SIP revisions that make changes to South Carolina's minor NSR requirements, as detailed herein. Specifically, the EPA is proposing to proposing to approve minor, administrative, and clarifying changes to South Carolina Regulation 61-62.1, Section II, Permit Requirements, subparagraph II(B)(2)(h), as described below, and to approve changes to the State's exemptions from the requirement to obtain a permit at subparagraph II(B)(2)(h), except for the second and third sentences of subparagraph
II(B)(2)(h),\6\ for the reasons discussed in section V of this NPRM. Additionally, the EPA is also proposing to approve minor and ministerial changes to South Carolina Regulation 61-62.1, Section II, Permit Requirements, paragraph II(K)(5), to reflect the restructuring of SC DHEC to the South Carolina Department of Public Health and SC DES. Section V.C., below, provides the EPA's analysis of the State's CAA section 110(l) non-interference demonstration for the portions that the EPA is proposing to approve.\7\
\6\ The second and third sentences the EPA is not incorporating by reference are the following: "Unless otherwise exempt, sources may be exempted under this section at higher emission levels if there is a demonstration that there are no applicable limits or requirements. These applicable requirements include federally applicable limits or requirements." \7\ See Section V.A. of this NPRM for more information.
II. Proposed Action
The EPA is proposing to approve minor, administrative, and clarifying changes to South Carolina Regulation 61-62.1, Section II, Permit Requirements, subparagraph II(B)(2)(h), as described above, and to approve changes to the State's exemptions from the requirement to obtain a permit at subparagraph II(B)(2)(h), except for the second and third sentences of subparagraph II(B)(2)(h).\10\ The EPA is proposing to approve the portions of the SIP revisions consisting of the aforementioned changes to subsection II(B) for the reasons discussed in section V of this NPRM. Additionally, the EPA is also proposing to approve minor and ministerial changes to South Carolina Regulation 61- 62.1, Section II, Permit Requirements, paragraph II(K)(5), to reflect the restructuring of SC DHEC to the South Carolina Department of Public Health and SC DES.
\10\ The second and third sentences the EPA is not incorporating by reference are the following: "Unless otherwise exempt, sources may be exempted under this section at higher emission levels if there is a demonstration that there are no applicable limits or requirements, These applicable requirements include federally applicable limits or requirements."