The U.S. Environmental Protection Agency (EPA) will put up for notice in the April 5 Federal Register its plan to approve a revision to North Carolina’s regional haze State Implementation Plan (SIP), submitted by the North Carolina Department of Environment and Natural Resources (NC DENR) in October 2014.
This revision relies on an alternative to Best Available Retrofit Technology (BART) to satisfy BART requirements for electric generating units (EGUs) formerly subject to the court-invalidated Clean Air Interstate Rule (CAIR). EPA also proposes to find that final approval of this SIP revision would correct the deficiencies that led to EPA’s limited disapproval of the state’s regional haze SIP in June 2012, and proposes to convert EPA’s June 2012 limited approval to a full approval.
Written comments must be received on or before 21 days after date of publication in the Federal Register.
North Carolina submitted its regional haze SIP in 2007. Fully consistent with EPA’s regulations at the time, the SIP relied on CAIR to satisfy NOx and SO2 BART requirements for CAIR-subject EGUs in the state and to partially satisfy the requirement for a long-term strategy sufficient to achieve the state-adopted reasonable progress goals. CAIR was struck down in court in 2008 and later replaced with the Cross-State Air Pollution Rule.
North Carolina’s October 2014 SIP revision relies on the state’s Clean Smokestacks Act (CSA) as a BART Alternative for NOx and SO2 at the BART-eligible EGUs formerly covered by CAIR. North Carolina enacted the CSA in 2002 to improve air quality by imposing firm caps on the total annual emissions of NOx and SO2 from 42 coal-fired EGUs at 14 power plants operated by Duke Energy Progress and Duke Energy Carolinas.
The CSA requires Duke Energy Carolinas EGUs and Duke Energy Progress EGUs to reduce SO2 emissions to 150,000 tons and 100,000 tons, respectively, by the end of 2009 and to further reduce SO2 emissions to 80,000 tons and 50,000 tons, respectively, by the end of 2013. The CSA limits NOx emissions from Duke Energy Carolinas EGUs and Duke Energy Progress EGUs to 35,000 tons and 25,000 tons, respectively, beginning on January 1, 2007, and tightens the emissions cap on Duke Energy EGUs to 31,000 tons as of January 1, 2009. Collectively, the caps require these utilities to: reduce actual emissions of NOx from 245,000 tons in 1998 to 56,000 tons by 2009 (a 77 percent reduction), and reduce actual SO2 emissions from 489,000 tons in 1998 to 250,000 tons by 2009 (a 49 percent reduction) and to 130,000 tons by 2013 (a 73 percent reduction).
Progress Energy Carolinas and Duke Energy Carolinas have shut down 22 of the coal-fired EGUs subject to the CSA and have installed flue gas desulfurization (FGD) to control SO2 emissions and Selective Catalytic Reduction (SCR) or Selective Non-catalytic Reduction (SNCR) to control NOx emissions on all of the currently operating coal-fired EGUs subject to the CSA in order to meet the emissions caps. The plants are:
- Allen Units 1-5, SNCR, FGD;
- Asheville Units 1-2, SCR, FGD;
- Buck Units 5-9, SNCR, converted from coal to natural gas;
- Belews Creek Units 1-2, SCR, FGD;
- Cliffside Unit 5-6, SCR, FGD;
- Marshall Units 1-2 and 4, SNCR, FGD;
- Marshall Unit 3, SCR, FGD;
- Mayo Unit 1, SCR, FGD; and
- Roxboro Units 1-4, SCR, FGD.
- Cape Fear Units 5-6;
- Cliffside Unit 4;
- Dan River Units 1-3;
- Lee Units 1-3;
- Riverbend Units 7-10;
- Sutton Unit 3; and
- Weatherspoon Units 1-3.