Air Plan Approval; South Carolina; Minor Source Permit Program Revisions

ENVIRONMENTAL PROTECTION AGENCY

40 CFR Part 52

Air Plan Approval; South Carolina; Minor Source Permit Program Revisions

Environmental Protection Agency (EPA).

Proposed rule.

The U.S. Environmental Protection Agency (EPA or Agency) is proposing action on changes to South Carolina's State Implementation Plan (SIP) to revise regulations prescribing minor source permitting program requirements, including minor new source review (NSR) requirements, involving, in part, minor source permitting public participation, in SIP revisions submitted by the State of South Carolina through the South Carolina Department of Health and Environmental Control (SC DHEC) on October 1, 2007; July 18, 2011; August 8, 2014; July 27, 2016; and April 24, 2020. This proposal supplements previous proposals the EPA published on August 17, 2017, and January 21, 2025. This proposal is being issued pursuant to the Clean Air Act (CAA or Act).

Comments must be received on or before September 18, 2026.

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.

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].

We use multiple abbreviations and terms in this notice of proposed rulemaking (NPRM). While this list may not be exhaustive, for ease of reading and for reference purposes, the EPA defines the following terms and acronyms here:

CAA Clean Air Act CFR Code of Federal Regulations EPA Environmental Protection Agency FESOP Federally Enforceable State Operating Permit FR Federal Register NAAQS National Ambient Air Quality Standard or Standards NNSR Nonattainment New Source Review NPRM Notice of Proposed Rulemaking NSR New Source Review PSD Prevention of Significant Deterioration PTE Potential to Emit SIP State Implementation Plan

Table of Contents

I. Executive Summary A. What action is the EPA proposing today? B. What is the legal authority and what are the requirements? II. Proposed Action III. Background A. Minor NSR Program

B. Minor NSR Program Public Participation Requirements C. Minor Source Operating Permitting Program D. South Carolina's Minor Source Permitting Program E. EPA's August 17, 2017, and January 21, 2025, Proposals IV. Summary of South Carolina's Submittals A. Subsection II(D) 1. Summary of Subsection II(D) Revisions 2. The EPA's Analysis of Subsection II(D) Revisions B. Subsection II(E) 1. Summary of Subsection II(E) Revisions 2. The EPA's Analysis of Subsection II(E) Revisions C. Subsection II(F) 1. Summary of Subsection II(F) Revisions 2. The EPA's Analysis of Subsection II(F) Revisions D. Subsection II(G) 1. Summary of Subsection II(G) Revisions 2. The EPA's Analysis of Subsection II(G) Revisions E. Subsection II(I) 1. Summary of Subsection II(I) Revisions 2. The EPA's Analysis of Subsection II(I) Revisions F. Subsection II(N) 1. Summary of Subsection II(N) Revisions 2. The EPA's Analysis of Subsection II(N) Revisions V. Incorporation by Reference VI. Statutory and Executive Order Reviews

On October 1, 2007; July 18, 2011; August 8, 2014; July 27, 2016; \1\ and April 24, 2020, SC DHEC \2\ submitted SIP revisions to the EPA for approval that include changes to South Carolina's minor source permitting regulations to clarify and streamline the State's federally approved minor source preconstruction and operating permit program. These regulations require minor stationary sources of air pollutants planning to construct or modify to first obtain a construction permit and to 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. The portion of the SIP-approved minor source permitting program covering operating permits also includes a program referred to as the federally enforceable State operating permit (FESOP) program. The EPA had previously proposed action on these submitted SIP revisions on January 21, 2025. See 94 FR 41591. This NPRM is intended to be in supplement to, and not replace, that prior proposed action. Here, the EPA is proposing to approve identified portions of the SIP submissions that make changes to South Carolina's minor source permitting program requirements contingent on the EPA finalizing a recently proposed change to relevant national regulations.\3\

\1\ While the July 27, 2016, submittal was signed and dated by SC DHEC on July 25, 2016, it was received via the EPA's SPeCS for SIPs system on July 27, 2016. \2\ 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 in the docket for this proposed rulemaking. In this NPRM, "State," "Department," "SC DHEC," and "SC DES" are interchangeable where applicable. \3\ In this NPRM, the EPA is not proposing to act on a portion of the revisions to Regulation 61-62.1, Section II. Specifically, the EPA is not proposing to act on changes to the following provisions: Section II prefatory text and subsections II(A); II(B); II(C); II(H); II(J); II(K); II(L); II(M); and II(O). The EPA proposed action on these subsections on August 8, 2017, NPRM (82 FR 39083) and on January 21, 2025, NPRM (90 FR 6954). The EPA is also proposed action on a portion of subsection II(B) in a separate NPRM.

Under CAA section 110(k)(3), the EPA has a statutory obligation to approve SIP submittals that meet all applicable CAA requirements.\4\ Pursuant to CAA section 110(k)(3), the EPA may approve portions of a SIP submittal if those portions meet all the applicable CAA requirements.

\4\ See 42 U.S.C. 7410(k)(3).

Additionally, under CAA section 110(l), the EPA cannot approve a SIP revision if it would interfere with any applicable requirement concerning attainment and reasonable further progress (as defined by CAA section 171), or any other applicable requirement of the CAA, including CAA section 110(l).\5\ The EPA evaluates CAA section 110(l) non-interference on a case-by-case basis considering the circumstances of each SIP revision.

\5\ CAA section 110(l) also requires each SIP revision to undergo reasonable notice and public hearing at the State level.

On July 7, 2026, the EPA published a proposal to revise the public participation regulatory requirements for sources subject to NSR programs in SIPs.\6\ If the EPA's July 7, 2026, NPRM is finalized as proposed, state and local air agencies would have the discretion to determine whether, and the extent to which, public participation elements are appropriate and reasonable in their minor NSR programs. For more information on the proposed revisions to the Federal minor NSR regulations and the rationale for the July 7, 2026, NPRM, please refer to the July 7, 2026, NPRM \7\ and related docket materials.\8\ Any comments on those proposed revisions and the EPA's rationale for those changes should be made on the July 7, 2026, NPRM and are not being solicited through this proposed action. If the EPA were to finalize the July 7, 2026, NPRM as proposed, the EPA is proposing to approve changes to South Carolina Regulation 61-62.1, Section II, Permit Requirements, subsections II(D), II(E), II(F), II(G), II(I), and II(N), for the reasons discussed in Section IV of this NPRM. This proposal supplements, and does not replace, previous proposals the EPA published on August 17, 2017,\9\ and January 21, 2025.\10\

\6\ See 91 FR 41591, "Minor New Source Review Program Air Permitting Public Participation Requirements for State Implementation Plans." \7\ See 91 FR 41591. \8\ Docket ID: EPA-HQ-OAR-2025-1212, available at https://www.regulations.gov/docket/EPA-HQ-OAR-2025-1212. \9\ See 82 FR 39083. \10\ See 90 FR 6954.