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Emissions During Periods of Startup, Shutdown, & Malfunction (SSM)

Findings of Substantial Inadequacy and SIP Calls to Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown, and Malfunction

February 15, 2023 - EPA proposed actions regarding state implementation plans or SIPs addressing air emissions during periods of startup, shutdown, and malfunction (SSM) in eight states. These plans must be reviewed by EPA to assure they comply with the Clean Air Act (CAA) and are consistent with the Agency’s SSM Policy as outlined in the 2015 SSM SIP Action. EPA is proposing to reinstate its findings of substantial inadequacy (“SIP calls”) that were withdrawn in 2020 for the states of Texas, North Carolina, and Iowa for SSM provisions in those states’ SIPs that do not comply with statutory requirements and EPA’s SSM Policy. For additional SSM provisions identified as deficient by EPA, the Agency is also proposing to issue new findings of substantial inadequacy and SIP calls to:

  • the state of Connecticut;

  • the state of Maine;

  • Shelby County, Tennessee;

  • the state of North Carolina;

  • Buncombe County, North Carolina;

  • Mecklenburg County, North Carolina;

  • the state of Wisconsin; and 

  • the state of Louisiana.

EPA will accept comment on this proposed action for 60 days after it is published in the Federal Register. 

Proposed Acton: State Implementation Plans: Findings of Substantial Inadequacy and SIP Calls to Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown, and Malfunction (pdf) (573.14 KB)

Fact Sheet: State Implementation Plans: Findings of Substantial Inadequacy and SIP Calls to Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown, and Malfunction (pdf) (187.89 KB)

 

Finding of Failure to Submit State Implementation Plan Revisions to Amend Provisions Applying to Excess Emission During Periods of Startup, Shutdown and Malfunction

January 4, 2022 - EPA is determining that 12 state or local air pollution control districts failed to submit State Implementation Plan (SIP) revisions in a timely manner to address EPA’s 2015 findings of substantial inadequacy for provisions applying to excess emissions during periods of startup, shutdown, and malfunction (SSM). These areas include: Rhode Island, the District of Columbia, Alabama, North Carolina – Forsyth, Tennessee – Shelby (Memphis), Illinois, Ohio, Arkansas, South Dakota, California – San Joaquin Valley Air Pollution Control District, Washington – Energy Facility Site Evaluation Council, and Washington – Southwest Clean Air Agency.

The findings establish a 24-month deadline for EPA to either approve SIPs or finalize Federal Implementation Plans addressing SSM provisions.  The findings also establish timelines for the implementation of two mandatory sanctions that will take effect if these areas do not submit complete SIPs to address the SSM provisions, as required by the Clean Air Act.  

Fact Sheet: Findings of Failure to Submit State Implementation Plan Revisions to Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown and Malfunction (pdf) (183.32 KB)

Final Action: Findings of Failure to Submit State Implementation Plan Revisions to Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown and Malfunction (pdf) (269.23 KB)

Guidance Memorandum: Withdrawal of the October 9, 2020, Memorandum Addressing Startup, Shutdown, and Malfunctions in State Implementation Plans and Implementation of the Prior Policy

September 30, 2021 - EPA is returning to its 2015 policy explaining that State Implementation Plan provisions that provide exemptions from air emissions limits during periods of startup, shutdown and malfunction (SSM) or that provide affirmative defense provisions are not consistent with the Clean Air Act and would not generally be approvable.  The reinstated 2015 Policy will ensure that all modes of source operation, including periods of SSM, have emissions limitations in place that can be appropriately enforced in all communities and populations across the affected states, including minority, low-income and indigenous populations overburdened by pollution. 

In addition, EPA plans to revisit the three related state-specific SIP actions that were finalized in 2020 that withdrew the SIP calls previously issued to Texas, North Carolina, and Iowa. Through notice-and-comment rulemaking actions EPA plans to reconsider whether any of the findings underlying those actions should be retained in light of the Agency’s change in policy.

Guidance Memo: Withdrawal of the October 9, 2020 Memorandum Addressing Startup, Shutdown, and Malfunctions in State Implementation Plans and Implementation of the Prior Policy (pdf) (4.24 MB)

October 9, 2020 Memorandum: Inclusion of Provisions Governing Periods of Startup, Shutdown, and Malfunctions in State Implementation Plans – EPA has withdrawn this memorandum.

Regional Updates

Iowa

On October 23, 2020, the Administrator of the EPA Region 7 Office signed a final rule to approve a State Implementation Plan revision submitted by the state of Iowa for the 2010 SO2 Muscatine, Iowa nonattainment area and to withdraw the SSM SIP Call for Iowa that was issued as part of the 2015 SSM SIP Action.

  • Region 7 Final Action: 2010 SO2 Attainment Plan Approval and SIP Call Withdrawal

On June 16, 2020, the Administrator of the EPA Region 7 Office signed a supplemental proposed rule to approve a State Implementation Plan revision submitted by the state of Iowa for the 2010 SO2 Muscatine, Iowa nonattainment area and to withdraw the SSM SIP Call for Iowa that was issued as part of the 2015 SSM SIP Action.

  • Region 7 Proposed Action: 2010 SO2 Attainment Plan Approval and SIP Call Withdrawal
  • Frequently Asked Questions and Answers about this proposal action

North Carolina

  • On April 2, 2020, the Administrator of the EPA Region 4 Office signed a final rule to approve a State Implementation Plan revision submitted by the state of North Carolina for a SIP-approved rule regarding nitrogen oxides (NOx) emissions from large internal combustion engine sources and to withdraw the SSM SIP Call for North Carolina that was issued during the 2015 SSM SIP Action.
    • Region 4 Final Action: SIP Call Withdrawal and Air Plan Approval; NC: Large Internal Combustion Engines NOx Rule Changes
    • Frequently Asked Questions and Answers about this final action 
  • On May 20, 2019, the Acting Administrator of the EPA Region 4 Office signed a proposal to approve a State Implementation Plan revision submitted by the state of North Carolina for a SIP-approved rule regarding nitrogen oxides (NOx) emissions from large internal combustion engine sources and to withdraw the SSM SIP Call for North Carolina that was issued during the 2015 SSM SIP Action.
    • Region 4 Proposed Action: SIP Call Withdrawal and Air Plan Approval; NC: Large Internal Combustion Engines NOx Rule Changes

Texas

  • On January 7, 2020, the Administrator of the EPA Region 6 Office signed a final action to withdraw the finding of substantial inadequacy for the Texas State Implementation Plan and to withdraw the SSM SIP Call for Texas that was issued during the 2015 SSM SIP Action.
    • Region 6 Final Action: Withdrawal of Finding of Substantial Inadequacy of Implementation Plan and of Call for Texas State Implementation Plan (SIP) Revision: Affirmative Defense Provisions for Malfunctions
    • Frequently Asked Questions and Answers about this final action
  • On April 23, 2019, the Acting Administrator of the EPA Region 6 Office signed a proposal to withdraw the finding of substantial inadequacy for the Texas State Implementation Plan and to withdraw the SSM SIP Call for Texas that was issued during the 2015 SSM SIP Action. 
    • Region 6 Proposed Action: Withdrawal of Finding of Substantial Inadequacy of Implementation Plan and of Call for Texas State Implementation Plan Revision - Affirmative Defense Provisions
  • On March 15, 2017, Texas submitted a petition for reconsideration of the final rule and requested an administrative stay of the action, with respect to the Texas State Implementation Plan (SIP). On October 16, 2018, EPA notified Texas that EPA had partially granted the petition and would use its discretion to reconsider the Texas SIP Call that was included in the 2015 SSM SIP Action.
    • Letter to Texas from EPA Region 6 Administrator Partially Granting Texas' Request for Reconsideration of the Texas SSM SIP Call

National Rule

On May 22, 2015, EPA issued a final rule to ensure states have plans in place that require sources across the country to follow air pollution rules during times when the facility is starting up or shutting down, or when a malfunction occurs (or "SSM").

Final Rule: State Implementation Plans: Response to Petition for Rulemaking; Restatement and Update of EPA’s SSM Policy Applicable to SIPs; Findings of Substantial Inadequacy; and SIP Calls to Amend Provisions Applying to Excess Emissions During Periods of Startup, Shutdown and Malfunction (PDF)(147 pp, 928 K, About PDF)

    • Fact Sheet on the Final Rule
    • List of Affected States (PDF)(147 pp, 928 K)

Background

  • Supplemental Proposal (PDF)(38 pp, 464 K) (September 5, 2014)
    • Fact Sheet on the Supplemental Proposal
  • Federal Register Proposed Rule (PDF)(82 pp, 675 K) (February 22, 2013)
    • Fact Sheet on the Proposed Rule
Contact Us to ask a question, provide feedback, or report a problem.
Last updated on February 16, 2023
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