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Cross-State Air Pollution Rule (CSAPR)

The U.S. Environmental Protection Agency’s Cross-State Air Pollution Rule requires 28 states in the eastern half of the U. S. to reduce power plant emissions that cross state lines and contribute to ground-level ozone and fine particle pollution in other states. A cap and trade system is used to reduce the target pollutants—sulfur dioxide and nitrogen oxides.

Summary: CSAPR

Latest CSAPR Actions

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Get more information on the Texas SIP and contact the TCEQ

Summary: CSAPR

On July 6, 2011, the United States Environmental Protection Agency (EPA) finalized a rule requiring 28 eastern states to reduce power plant emissions that contribute to pollution from ozone and fine particulate matter (PM2.5) in other states. The final rule was published in the Federal Register on August 8, 2011 (76 FR 48208Exit the TCEQ. The rule is intended to help eastern states meet Federal Clean Air Act (FCAA) obligations regarding interstate transport of air pollution for the 1997 ozone and PM2.5 and 2006 PM2.5 National Ambient Air Quality Standards. The rule requires reductions in ozone season nitrogen oxide (NOx) emissions that cross state lines for states under the ozone requirements, and reductions in annual sulfur dioxide (SO2) and NOx for states under the PM2.5 requirements.  To assure emissions reductions, the EPA promulgated federal implementation plans (FIPs) for each of the states covered by the rule. The rule is intended to replace the EPA’s Clean Air Interstate Rule (CAIR).

Texas was included in the CSAPR FIP for the ozone and PM2.5 trading programs, though was initially proposed only for inclusion in the ozone trading program. For more information on unit-level allocations for electric generating units in Texas, please visit the EPA’s Cross-State Air Pollution Rule (CSAPR) Allowance Allocations and Templates Web page Exit the TCEQ.

Latest CSAPR Actions

On August 21, 2012, the United States Court of Appeals for the D.C. Circuit vacated CSAPR and ordered the EPA to continue to administer CAIR while it works on a replacement transport rule. The Court determined that CSAPR exceeds the EPA’s statutory authority in two independent respects. First, the statute grants EPA authority to require upwind states to reduce only their own significant contributions to a downwind state’s nonattainment. However, under CSAPR, the EPA imposed massive emissions reduction requirements on upwind states without regard to the limits imposed by the statute.

Second, the FCAA allows states the initial opportunity to implement reductions required by the EPA. In the case of CSAPR, the EPA quantified states’ obligations and did not allow the states the initial opportunity to implement the required reductions with respect to sources within their borders. Instead, the EPA quantified states’ obligations and simultaneously set forth FIPs to implement those obligations at the state level.

The EPA and various environmental groups petitioned the Supreme Court of the United States to review the D.C. Circuit Court's decision on CSAPR. On June 24, 2013, the Supreme Court granted the petitions and heard oral arguments in the case on December 10, 2013. On April 29, 2014, a decision by the Supreme Court Exit the TCEQ reversed the D.C. Circuit's ruling and remanded the case. On October 23, 2014 the D.C. Circuit Court lifted the stay of CSAPR and heard oral arguments on the remand on February 25, 2015.

The EPA updated portions of CSAPR Exit the TCEQ to align with the court's schedule on November 21, 2014. Phase 1 of CSAPR took effect January 1, 2015 and Phase 2 was scheduled to begin January 1, 2017.

On July 28, 2015, the U.S. Court of Appeals for the D.C. Circuit found that the CSAPR 2014 SO2 and ozone season NOX budgets for Texas and certain other states were invalid because the budgets required more emission reductions than was necessary. The court remanded without vacatur to the EPA for reconsideration of the emission budgets.

On October 26, 2016, the EPA published the final CSAPR Update Rule Exit the TCEQ for the 2008 eight-hour ozone standard. The EPA’s modeling showed that emissions from within Texas no longer significantly contribute to downwind nonattainment or interference with maintenance for the 1997 ozone NAAQS even without implementation of the original CSAPR NOX ozone season emission budget. Accordingly, sources in Texas are no longer subject to the emissions budget calculated to address the 1997 ozone NAAQS. However, this rule finalized a new ozone season NOX emissions budget for Texas to address interstate transport with respect to the 2008 ozone NAAQS. This new budget is effective for the 2017 ozone season, the same period in which the Phase 2 budget that was invalidated by the court was scheduled to become effective. This final rule did not address the remand of the CSAPR Phase 2 SO2 annual emission budgets.

On June 27, 2016, the EPA issued a memorandum outlining the agency’s approach for responding to the D.C. Circuit’s July 28, 2015 remand of the original CSAPR Phase 2 emissions budgets, providing a choice of two paths for states with remanded budgets. Under the first path, states can voluntarily continue to participate in CSAPR at the state’s current Phase 2 SO2 and annual NOX budget levels through a SIP revision. Under the second path, if a state does not choose to participate in CSAPR, the EPA would initiate rulemaking by Fall of 2016 to remove the state’s sources from CSAPR’s SO2 and annual NOX programs and address any remaining interstate transport or regional haze obligations on a state-by-state basis. On November 10, 2016, the EPA published a proposed rule Exit the TCEQ to remove Texas sources from the CSAPR SO2 and annual NOX trading programs. The EPA also proposed to determine that, following withdrawal of the FIP requirements, sources in Texas will not contribute significantly to nonattainment or interfere with maintenance of the 1997 PM2.5 NAAQS in any other state and that the EPA therefore will have no obligation to issue new FIP requirements for Texas sources to address transport for the 1997 PM2.5 NAAQS.

Related Web pages

EPA Information on CSAPR Exit the TCEQ

EPA CSAPR Regulatory Actions and Litigation Exit the TCEQ

TCEQ CAIR Web page

Get more information on the Texas SIP and contact the TCEQ

TCEQ SIP Contacts