U.S. EPA Proposes SIP Calls for States with SSM Exemption Provisions
Posted: March 27th, 2023
Authors: Lindsey K.
On February 24, 2023, the United States Environmental Protection Agency (U.S. EPA) proposed to reinstate State Implementation Plan (SIP) Calls for three states and issue new SIP Calls for eight states and local jurisdictions. All of the proposed SIP Calls pertain to provisions in the SIPs that allow for excess emissions during periods of startup, shutdown, and malfunction (SSM).
This action is one of several taken by U.S. EPA regarding SIP SSM provisions since 2015, and U.S. EPA provides a timeline of those actions in the Federal Register notice for context. To summarize, in 2015 U.S. EPA reestablished and updated its policy that SIP provisions allowing for excess emissions during periods of SSM were not permissible (2015 SSM Policy) and determined that the SIPs for 45 state and local jurisdictions conflicted with that policy and were therefore substantially inadequate. U.S. EPA issued SIP Calls to require those SIPs to be updated; however, the SIP Calls for Texas, North Carolina, and Iowa were rescinded in February 2020, April 2020, and November 2020, respectively, based on regional determinations that those SIPs were not, in fact, substantially inadequate. Of note, but without getting into the details, U.S. EPA weakened its 2015 SSM Policy via an October 2020 memo, which supported the Iowa SIP Call recission, but that memo was withdrawn in September 2021.
U.S. EPA has now proposed to reinstate the SIP Calls for those three states, and to issue new SIP Calls for eight states and local jurisdictions. The table below provides a brief summary of the state and local jurisdiction SIP provisions for which U.S. EPA has proposed to reinstate or issue SIP Calls, and U.S. EPA’s reasoning for those provisions being substantially inadequate.
State/Jurisdiction |
Provision |
Inadequacy |
Reinstated SIP Calls |
||
| Iowa | IAC 567-24.1(1) | Impermissible automatic exemption
Allows for excess emissions during periods of startup, shutdown, and cleaning of control equipment. |
| North Carolina | 15A NCAC 02D .0535(c) and (g) | Impermissible director’s discretion exemption
State agency has discretion to exempt excess emissions during SSM events. |
| Texas | 30 TAC 101.222(b)-(e) | Impermissible affirmative defense
Rule contains “affirmative defenses as to civil penalties for sources of excess emissions that occur during” upsets, unplanned events, and unplanned maintenance, startup, and shutdown (MSS) activities. |
New SIP Calls |
||
| Connecticut | CT Sec. 22a-174-38(c)(11) | Impermissible automatic exemption
CO and opacity limits for municipal waste combustors (MWC) allow for defined durations of SSM to be excluded). |
| Louisiana | LA. Admin Code Tit. 33 section 917 | Impermissible director’s discretion exemption
“Authorizes a state official to grant a ‘variance’ from any generally applicable SIP emission limitation if the state official ‘finds that by reason of exceptional circumstances strict conformity with any provisions of [Louisiana’s air quality] regulations would cause undue hardship, would be unreasonable, impractical or not feasible under the circumstances.’” |
| Maine | ME 06-096 Chapter 138-3-O | Impermissible automatic exemption
NOX Reasonably Available Control Technology (RACT) stationary sources using continuous emissions monitoring systems (CEMS) can exclude periods of startup, shutdown, equipment malfunction and fuel switching from 24-hour daily block arithmetic average emission rates. |
| ME 06-0096 Chapter 150-4-C | Impermissible automatic exemption
Visible emission standard for outdoor wood boilers and outdoor pellet boilers allows for defined durations to be excluded. |
|
| North Carolina | 15A NCAC 02D .1423(g) | Impermissible automatic exemption
Emission standards for large internal combustion engines allow for defined durations of SSM and maintenance to be excluded. |
| North Carolina (Buncombe County) | WNCRAQ Air Quality Code section 1-137(c) | Impermissible director’s discretion exemption
Excess emissions may be permissible if demonstrated to the Director that they are due to a malfunction. |
| North Carolina (Mecklenburg County) | MACAPCO Rule 2.0535(c) | Impermissible director’s discretion exemption
Excess emissions may be permissible if demonstrated to the Director that they are due to a malfunction. |
| Tennessee (Shelby County) | Shelby County Air Code 3-17 (City of Memphis Code 16-83). | Impermissible unbounded director’s discretion exemptions
“Allows a state official to excuse excess visible emissions after giving ‘due allowance’ to the fact that they were emitted during startup or shutdown events.” |
| Wisconsin | Wis. Admin. Code provisions NR 431.05(1) | Impermissible automatic exemption
Allows for opacity exceedances when combustion equipment is being cleaned or a new fire is being started. |
| Wis. Admin. Code provisions NR 431.05(2) | Impermissible unbounded director’s discretion exemptions
Allows for opacity exceedances from portable sources “for stated periods of time, as permitted by the department, for such purpose as an operating test, use of emergency equipment, or other good cause, provided no hazard or unsafe condition arises.” |
|
| Wis. Admin. Code provisions NR 436.03(2) | Impermissible director’s discretion exemption
Allows for emissions exceedances under defined circumstances, including when there is a correction plan; during scheduled maintenance, startup, or shutdown; or certain uses of emergency equipment. |
|
Comments on U.S. EPA’s proposed findings of substantial inadequacy and reinstatement/issuance of SIP Calls are due by April 25, 2023. In the final action, U.S. EPA will establish deadlines by which states and local jurisdictions must submit revisions to their SIPs. U.S. EPA is proposing to grant the maximum amount of time allowed by the Clean Air Act (CAA), 18 months, for states and local jurisdictions to submit SIP revisions. U.S. EPA states this timeline is appropriate “considering the affected air agencies’ need to develop appropriate regulatory provisions to address the SIP call and conduct any required processes for developing a SIP.” Indeed, in order to submit a SIP revision, states and local jurisdictions will need to propose amendments, receive and consider comments, and finalize the underlying regulations before submitting the SIP revisions to U.S. EPA for consideration.
States and local jurisdictions have discretion to decide how to address the provisions that U.S. EPA has proposed to find substantially inadequate. For example, in cases where a regulation contains an automatic exemption, they may elect to eliminate the exemption, or put an alternate standard in place. As a regulated entity, consider how the affected provisions are applicable to your operations, and how changes to those provisions may impact your operations. Stay engaged in the rulemaking process – review the proposed changes, attend public hearings, and consider submitting comments.
We will continue following this action and post an update when finalized. Please contact Lindsey Kroos or your Project Manager with questions or for support with the rulemaking process.
