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Air Quality

Clean Air Interstate Rule (CAIR) - Allocations

CAIR is in effect while EPA develops a replacement rule to respond to the U.S. Court of Appeals, D.C. Circuit, remand on December 23, 2008.

Annual Allocations

Please use the links below for more information on Annual Allocations of the CAIR program.

Overview

DHEC, in cooperation with the Clean Air Markets Division of the EPA, administers the CAIR NOX Trading Program. DHEC determines the allocations, also known as allowances or NOX credits for each facility subject to the CAIR in South Carolina. DHEC makes this determination according a regulatory formula, that uses heat input data and the type of fuel burned, coal or natural gas in most cases.

The Annual Allocations are for the January to April and October to December NOX Trading Program.

On September 20, 2007, DHEC submitted the following allocations to EPA: SC CAIR EGU Annual Allocations for 2009-2012 (xls).

State Annual NOX Budget

The South Carolina trading budget for annual allocations of CAIR NOX allowances for the control periods from 2009 through 2014 is 32,662 tons, and in 2015 and thereafter is 27,219 tons.

DHEC will allocate 97% of these allowances to CAIR NOX units, 31,682 tons in 2009-2014, and 26,402 tons in 2015 and thereafter.

DHEC will reserve the other 3% for New Units in the New Unit Set-aside program, which is 980 tons in 2009-2014, and 817 tons in 2015 and thereafter.

New Unit Set-aside Applicability

New Unit Set-aside program only Applies to CAIR NOX Annual and Ozone Season Units.

A unit that is not allocated CAIR NOX allowances under South Carolina Air Pollution Control Regulation 61-62.96.142(b) because the unit does not yet have a baseline heat input under South Carolina Air Pollution Control Regulation 61-62.96.142(a) or;

Because all CAIR NOX allowances available under South Carolina Air Pollution Control Regulation 61-62.96.142(b) for the control period are already allocated.

Applicability

In general, a CAIR unit must:

  1. Be a stationary boiler or combustion turbine
  2. Combust any amount of fossil fuel;
  3. Serve an electric generator with a nameplate rating greater than 25 MWe and;
  4. Supply 1/3 or more of its annual potential electric output to a utility power distribution system for sale.

If a unit qualifies as a "solid waste incineration unit" and meets the criteria, it is not automatically subject to CAIR. Such a unit would automatically become subject to CAIR if either: Fossil fuel combustion comprises an average of at least 20% of total annual heat input for 3 consecutive years, or; the unit no longer meets all qualifications under paragraphs (b)(2)(i) or (ii) of each of the relevant CAIR programs (40 CFR §§96.104, 96.204, 96.304).

Timing of Allocations for Annual Program

Regular Allocation

By April 30, 2007, DHEC submitted the allowance allocations to the EPA for the 2009-2012 control periods.

By September 30, 2007, the EPA will record allowances allocated for the 2009-2014 control periods.

By October 31, 2009, and October 31 of every 4th year thereafter, DHEC will submit allowance allocations to the EPA for the control periods in the 4th, 5th, 6th, and 7th years after the year of the abovementioned deadlines. On October 31, 2009, the 2013-2016 allocations are due. On October 31, 2013, the 2017-2020 allocations are due.

By December 1, 2009, the EPA will record allowances allocated for the 2015 control period.

By December 1, 2009, and December 1 of every 4th year thereafter, the EPA will record allowances allocated for the control period in the sixth year after the year of the applicable deadline for recordation under this paragraph. On December 1, 2009, 2015 allocations recorded, and on December 1, 2013, 2019 allocations recorded.

New Unit Set-aside Allocation

By May 1, 2009, and May 1 of every year thereafter, new unit set-aside allowance requests are due to DHEC, based on data from the calendar year prior to the year of the request.

By October 31, 2009, and October 31 of every year thereafter, DHEC will submit allocations for new units from the new unit set-aside account for the control period of the year of the abovementioned deadline.

By December 1, 2009, and December 1 of every year thereafter, the EPA will record allowances allocated for the control period in the year of the applicable deadline for recordation under this paragraph.

New Unit Set-aside Procedure

DHEC will establish a new unit set-aside for each control period.

CAIR NOX Annual new unit set-aside

  • 3% of the State NOX Annual budget
  • 2009-2014 = (32,662 tons * .03) or 980 tons
  • 2015 and thereafter = (27,219 tons * .03) or 817 tons

NOX Annual Control Period

The CAIR NOX Annual program (subject to subparts AA - II) Control Period is:

  • Jan 1 - April 30, and
  • October 1 December 31.

The CAIR NOX Ozone Season program (subject to subparts AAAA IIII) Control Period is:

  • May 1 September 30.

Electricity-generating Units (EGUs) in the CAIR program are subject to both the NOX Annual and Ozone Season programs.

Non-electricity-generating Units (Non-EGUs) in the CAIR program are only subject to the CAIR NOX Ozone Season program.

Allocations

Allowances for the 2009-2012 control periods use the single highest adjusted control period heat input data from years 2002-2005.

Allowances for the 2013-2016 control periods use the single highest adjusted control period heat input data from years 2005-2008.

Allowances for the 2017-2020 control periods use single highest adjusted control period heat input data from 2009-2012.

The heat input from the data that is determined to be the highest (as described above) will be adjusted by: A) If the unit is coal-fired during the year, the unit's control period heat input for such year is multiplied by 1.0 (100 percent); or B) If the unit is not subject to the provision above, the unit's control period heat input for such year is multiplied by 0.60 (60 percent).

DHEC will allocate CAIR NOX allowances to each CAIR NOX unit in an amount determined by: Multiplying the total amount of CAIR NOX allowances allocated (97% of State Budget) by the ratio of the baseline heat input of such CAIR NOX unit to the total amount of baseline heat input of all such CAIR NOX units in the State and rounding to the nearest whole allowance as appropriate.

  • Allocation = (97% of State Budget) * [(BHI of Unit) / (Total BHI of all Units)]

Timing for New Unit Set-aside program

By May 1, 2009, and May 1 of every year thereafter, facilities subject to CAIR must submit a CAIR NOX allowance allocation for the year of the deadline.

On or after May 1, 2009 and May 1 of every year thereafter, DHEC will determine allowances for each unit that submits a request for the year of the deadline.

By October 31, 2009, and October 31 of every year thereafter, DHEC will submit allocations to EPA for new units from the new unit set-aside account for the control period of the year of the abovementioned deadline.


For more information please contact the Bureau of Air Quality at (803) 898-4123 or by email.