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

Guidance Memorandum:  Inclusion of provisions governing periods of Startup, Shutdown, and Malfunctions in State Implementation Plans

On October 9,2020, EPA issued guidance outlining whether and when it may be permissible for a state to include certain types of provisions governing periods of startup, shutdown, and malfunction (SSM) in state implementation plans (SIPs) developed to assure attainment and maintenance of the National Ambient Air Quality Standards (NAAQS). This updated guidance recognizes that SIPs contain numerous planning requirements that collectively protect the NAAQS. A SIP can adequately provide for attainment and maintenance of the NAAQS, even if the SIP allows exemptions to specific emission limits for SSM events. The guidance released today also acknowledges that affirmative defense provisions for malfunction periods may be acceptable because penalties for sudden and unavoidable malfunctions caused by circumstances beyond the control of the owner or operator may not be appropriate.

Inclusion of Provisions Governing Periods of Startup, Shutdown, and Malfunctions in State Implementation Plans

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