On October 26, 2016, EPA published a final rule in the Federal Register updating its emission budget for oxides of nitrogen (NOX) for electric generating units in 22 eastern states that are deemed to significantly contribute to nonattainment or interference with maintenance of the 2008 ozone NAAQS in downwind states. The required reductions in NOX emissions is intended to reduce ozone season emissions to help achieve compliance with the 2008 ozone NAAQS. The Cross-State Air Pollution Rule (CSAPR) Update establishes federal implementation plan budgets in each of the 22 states that apply beginning with the 2017 ozone season (May 1 through September 30). Of significance, the NOX emission budgets are designed and established with respect to 2008 ozone NAAQS and not the more stringent 70 ppb 2015 8 -hour ozone NAAQS. The emission budgets are estimated to reduce ozone season NOX emissions from power plants in the eastern United States by 20 percent in 2017 as compared to 2015 levels. The emission budgets for each of the 22 states are to be achieved through allowance trading programs. The power industry contends that the mandatory emission budgets are not necessary given the reduction in NOX emissions that are otherwise occurring due to unit retirements and conversions.