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New Source Review (NSR) Permitting

Project Emissions Accounting

October 22, 2020 - EPA is finalizing a rule to clarify the process for evaluating whether the New Source Review (NSR) permitting program would apply to proposed projects at existing air pollution sources. This rule makes it clear that both emissions increases and decreases from a major modification at an existing source can be considered during Step 1 of the two-step NSR applicability test. This process is known as project emissions accounting (previously referred to as project netting).

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  • Project Emissions Accounting (PDF)(75 pp, 642 K, October 22, 2020)
    This rule makes it clear that both emissions increases and decreases from a major modification at an existing source can be considered during Step 1 of the two-step NSR applicability test.
  • Project Emissions Accounting Fact Sheet (PDF)(2 pp, 153 K, October 22, 2020)
    Fact Sheet describing Project Emissions Accounting final rule