Questions or Comments:
You are here:

SIP Revision: Regional Haze

The regional haze revision to the State Implementation Plan (SIP) for air quality is the plan Texas must submit to the United States Environmental Protection Agency to show how the state will reduce regional haze in the air to natural background conditions.

New Public Comment Period Extension for the Proposed 2021 Regional Haze SIP Revision

The proposed 2021 Regional Haze SIP Revision (Project No. 2019-112-SIP-NR) narrative and public hearing notice stated that the commission must receive all written comments by December 9, 2020. The commission has extended the deadline for receipt of written comments on the proposal to January 8, 2021. For more information, please visit the Proposed SIP Revisions and Public Hearing Information section of the Texas SIP Revisions webpage.

Federal Land Manager (FLM) Consultation Documentation for the Proposed 2021 Regional Haze SIP Revision

Proposed 2021 Regional Haze SIP Revision

On October 7, 2020, the commission approved proposal of the 2021 Regional Haze SIP Revision (Project No. 2019-112-SIP-NR). The proposed SIP revision would demonstrate compliance with the regional haze requirements of the Federal Clean Air Act, §169A and the United States Environmental Protection Agency’s (EPA) Regional Haze Rule for the second planning period. The proposed SIP revision addresses regional haze in Big Bend and Guadalupe Mountains National Parks in Texas and Class I areas located outside Texas that may be affected by emissions from within the state.

The public comment period opened on October 9, 2020 and was originally scheduled to close on December 9, 2020. The commission has extended the public comment period to January 8, 2021. A virtual public hearing on the proposed SIP revision will be held on December 8, 2020 at 2:00 p.m. Central Standard Time. Individuals who plan to attend the hearing must register by December 1, 2020. For information about how to register, please visit the Proposed SIP Revisions and Public Hearing Information section of the Texas SIP Revisions webpage. 

2017 Amendments to the Regional Haze Rule

On January 10, 2017, the EPA published the final Amendments to the Regional Haze Rule (82 FR 3078Exit the TCEQ) to update aspects of the reasonably available visibility impairment (RAVI) and regional haze programs including:

  • strengthening the federal land manager consultation requirements;
  • extending the RAVI requirements so that all states must address situations where a single source or small number of sources is affecting visibility at a Federal Class I area;
  • extending the SIP submittal deadline for the second planning period from July 31, 2018 to July 31, 2021 to allow states to consider planning for other federal programs like the 2010 one-hour SO2 NAAQS, and the 2012 annual PM2.5 NAAQS;
  • adjusting interim progress report submission deadline so that second progress reports would be due by January 31, 2025; and
  • removing the requirement for progress reports to be SIP revisions so the EPA would not formally approve or disapprove them.

On January 17, 2018, the EPA announced its decision to revisit certain aspects of the 2017 Regional Haze Rule revisions.

The EPA’s draft guidanceExit the TCEQ on the rule was released on June 30, 2016. In January 2018, the EPA announced plans to finalize one or more EPA guidance documents for regional haze state implementation plan (SIP) revisions due in 2021.

2014 Five-Year Regional Haze SIP Revision

At the February 26, 2014 agenda, the commission adopted the 2014 Five-Year Regional Haze SIP Revision. This SIP revision evaluated Texas’ progress towards the “reasonable progress” goal for each Federal Class I area in the state, and each Federal Class I area outside the state that may be affected by emissions from Texas. The TCEQ projects that Texas will meet the established “reasonable progress” goals set by the state for 2018 for all Class I areas it affects.

This five-year progress report does not require modeling and uses the analysis in the 2011 Interagency Monitoring of Protected Visual Environments (IMPROVE) report to show whether the Class I areas of concern are on the glide path. The EPA guidance for the five-year progress report was released on April 12, 2013. No rulemaking was proposed with this SIP revision, which is project number 2013-013-SIP-NR.


Key dates for 2014 Five-Year Progress Report SIP revision:

  • Adopted: February 26, 2014
  • Due to EPA: March 2014
  • Federal Land Managers and EPA comment period: June 19 through August 20, 2013
  • Public comment period: August 21 through October 1, 2013
  • Public Hearing: September 24, 2013

Key dates in past and future SIP revisions:

  • TCEQ adoption date for initial SIP: February 25, 2009
  • EPA's evaluation of 2009 SIP revision: resulted in two federal implementation plans (FIP)
    1) the January 2016 final reasonable progress FIP and
    2) the October 2017 final BART FIP (see descriptions and links below)
  • New Amendments to the Regional Haze Rule: January 10, 2017 (82 FR 3078Exit the TCEQ)
  • Next revision due: July 31, 2021 (extended from 2018 to 2021 per the new amendments)
  • Review every five years: through 2064 or until natural conditions are met

EPA's 2016 and 2017 Federal Implementation Plans (FIP)

On January 5, 2016, the EPA finalized a partial disapproval of the Texas 2009 RH SIP revision and issued a reasonable progress FIP (81 FR 296Exit the TCEQ, effective February 4, 2016). The FIP included requirements for control upgrades or new emissions limits at eight coal-fired power plants in Texas. The FIP stated that seven power plants install additional emissions controls on specific units within three or five years of the effective date of the rule. This FIP was stayed, then sent back to EPA for changes. The EPA also approved the Texas Best Available Retrofit Technology (BART) rule with regard to non-electric generating units (EGU); however, the EPA did not take action on BART for EGUs due to continuing issues with the EPA's Cross-State Air Pollution Rule.

In the October 17, 2017 Federal Register (82 FR 48324Exit the TCEQ), the EPA issued a final BART FIP for EGUs, which included an alternative trading program for SO2. The EPA will administer the trading program, which included only specific EGUs in Texas and no out-of-state trading. The EGUs included: Big Brown, Coleto Creek, Deely, Fayette, Graham, Harrington, Limestone, Martin Lake, Monticello, Newman, Parish, Pirkey, Sandow, Sommers, Stryker Creek, Tolk, Welsh, and Wilkes. For NOX, Texas will remain in CSAPR. For PM, the EPA determined no further action was required. The EPA decided that the final FIP satisfied interstate visibility transport for all six NAAQS.

In October 2017, Luminant announced the retirement in early 2018 of three coal fired power plants, which are listed in the FIP: Big Brown, Sandow, and Monticello. 

2009 Regional Haze SIP

On February 25, 2009, the commission adopted revisions to the Texas SIP for visibility protection at Federal Class I areas. No rulemaking occurred with this SIP. The revision was project No. 2007-016-SIP-NR.

The regional-haze SIP revision is the plan Texas must submit to the EPA to show how Texas will reduce regional haze to natural conditions. This SIP revision includes all existing control strategies for the Dallas and Houston areas, other statewide and federal controls, and BART.

The long-term goal is to restore air quality to natural conditions—defined by the EPA as the visibility conditions that would be experienced in the absence of pollution from human activities. The goal set by Congress is for all Federal Class I areas to meet natural conditions by 2064. The “glide path” is the path to the 2064 goal. Currently, the baseline haze level at Big Bend and Guadalupe Mountains National Parks is approximately 16 deciviews.

Chart showing Natural conditions in 60 years.


Solid red line represents glide path.
Source: Adapted from EPA-454/B-03-005, Guidance for Estimating Natural Visibility Conditions Under the Regional Haze Program.

The BART Rule was adopted by the TCEQ in January 2007 to allow the state to require BART modeling from specific industries or sources. A number of sources that appeared to be BART-eligible applied for and obtained legally enforceable reductions in their allowable emissions. Some of the reductions were from shutdowns; others resulted from reducing permitted emissions rates on units that had larger allowables than they needed to operate. After final modeling incorporated these reductions in allowable emissions, Texas was left with no BART-eligible sources. An updated list of potentially BART-eligible sources is in SIP Appendix 9-13. For more information on BART, see the related Regional Haze: Rulemaking (BART and CAIR) webpage.

Texas used the Central Regional Air Planning Association’s template for the regional haze SIP revision. The CENRAP states worked together with the EPA and federal land managers to develop a format that stakeholders found acceptable. Each state adapted the template as needed.

Technical Issues

Consultation with Other States
The TCEQ provided a summary paper to participants in the regional-haze consultation calls on July 11, 18, and 31, 2007. The TCEQ held these calls with other states, federal land managers, and the EPA and offered the opportunity for other interested parties to listen to the calls.

Texas’ Regional Haze Summary of Major Issues is the summary the TCEQ provided to the participants in the consultation conference calls. The summaries of the three consultation conference calls appear below:

The TCEQ continues to consult with other states. Regional haze SIP revisions are required every 10 years. Every five years, the TCEQ is required to assess the state's progress towards natural conditions.

The TCEQ developed four issue papers regarding its analyses of some of the technical issues in developing the 2009 regional-haze SIP revision and supplied those papers to the participants in the consultation calls.

Technical Papers

  • Uniform Rates of Progress and Projected 2018 Reasonable Progress Goals. The first issue concerned the uniform rate of progress to reduce haze by 2018. The TCEQ's preliminary analyses indicate that, without international emissions, Texas' Class I areas would be close to achieving the uniform rate of progress for 2018.
  • Dust Storms and Regional Haze. The second issue concerned natural events that contribute to regional haze. Texas cannot control these natural events, and consequently these events are considered part of the natural conditions in developing a regional haze SIP.
  • Estimating Natural Conditions Based on Revised IMPROVE Algorithm. The third issue concerned natural conditions, or conditions that would be present without pollution from human activities. The IMPROVE algorithm was revised in 2005. The Texas 2009 regional haze SIP revision used the revised IMPROVE equation for all baseline, control-strategy, and natural-condition calculations.
  • Integrated Planning Model Projections of Electric Generating Unit Emissions for the Regional Haze SIP Revision The fourth issue concerned the use of the EPAs Integrated Planning Model, Version 2.19, versus Version 3.0. Based on its analyses, the TCEQ concluded that photochemical modeling using inputs for electric generating units from the earlier version of the IPM was a viable option for this SIP planning period.


Federal Land Managers’ Comments

As required by the Regional Haze Rule, 40 CFR 51.308, the TCEQ made the Federal Land Managers' comments available before the public hearing. The following comments were received:

Other Comments

The following comments are in no particular order.