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Date Change Affirmation Rules for the Cross-State Air Pollution Rule (CSAPR)

The timing of CSAPR's implementation was affected by a number of court actions. On December 30, 2011, CSAPR was stayed prior to implementation. On April 29, 2014, the U.S. Supreme Court issued an opinion reversing an August 21, 2012 D.C. Circuit decision that had vacated CSAPR. Following the remand of the case to the D.C. Circuit, EPA requested that the court lift the CSAPR stay and toll the CSAPR compliance deadlines by three years. On October 23, 2014, the D.C. Circuit granted EPA's request. Accordingly, CSAPR Phase 1 implementation began in 2015, with Phase 2 beginning in 2017.

February 26, 2016

EPA issued a ministerial action affirming changes to CSAPR that align the dates in CSAPR's rule text with its revised implementation schedule - 2015 Phase 1 implementation and 2017 Phase 2 implementation. This change was made in 2014 on an interim basis. This action makes no further changes to CSAPR.


November 21, 2014

EPA issued two ministerial actions to align certain aspects of CSAPR with the revised court-ordered schedule.

Interim Final Rule

EPA issued a ministerial rule that aligns the dates in the CSAPR rule text with the revised court-ordered schedule, including 2015 Phase 1 implementation and 2017 Phase 2 implementation.

Notice of Data Availability

EPA issued a NODA, as required by CSAPR, that aligns the final CSAPR default allowance allocation years with the revised court-ordered schedule.