Emissions Inventory (EI) reporting applicability is based on attainment status of the county where the site is located, the potential to emit (PTE) of regulated pollutants and hazardous air pollutants (HAPs), and actual emissions of regulated pollutants and HAPs. (See 30 TAC Section 116.12 for the major source classifiations and PTE thresholds.) Applicability also applies to any source subject to special inventories, under 30 TAC Section 101.10(b)(3). If a site meets any of the EI reporting requirements at any time during the calendar year, an EI report is required. Annual reports must be submitted by March 31, 2020 and must be submitted using the State of Texas Environmental Electronic Reporting System (STEERS) Annual Emissions Inventory web-based system.

TCEQ emphasized the following information for the Emissions Inventory RY 2019:

Reclassification Notice

The Houston-Galveston-Brazoria (HGB) and Dallas-Fort Worth (DFW) areas have been reclassified to serious nonattainment under the 2008 ozone standard. Because of this, Potential to Emit (PTE) major source thresholds for counties within these areas has decreased from 100 tons per year (tpy) to 50 tpy. This affects emissions inventory reporting for the following counties: Brazoria, Chambers, Collin, Dallas, Denton, Ellis, Fort Bend, Galveston, Harris, Johnson, Kaufman, Liberty, Montgomery, Parker, Rockwall, Tarrant, Waller, and Wise.

Special EI

Special EI applies to entities that have received a written request from the TCEQ. Sites are required to respond to the letter even if the site does not meet reporting thresholds. For RY 2019, this applies to regulated entities that emitted at least 10 tpy of volatile organic compounds (VOC) or 25 tpy of oxides of nitrogen (NOx) in one of the following counties: Bastrop, Bell, Caldwell, Comal, El Paso, Gregg, Guadalupe, Hardin, Harrison, Hays, Henderson, Hood, Jefferson, McLennan, Nueces, Orange, Rusk, San Patricio, Smith, Travis, Upshur, Victoria, Williamson, Wilson. If you receive a letter from the TCEQ, but the site does not meet the reporting thresholds specified in 30 TAC Section 101.10 or Special EI requirements, a letter may be sent instead of a full EI. A sample letter can be found in Appendix B of the2019 Emissions Inventory Guidelines .

Determining Emissions from Storage Tanks

The TCEQ recommends using the Compilation of Air Pollutant Emissions Factors (AP-42), Chapter 7 equations to determine emissions from tanks. The U.S. Environmental Protection Agency (EPA) finalized updates to AP-42, Chapter 7 in November 2019.

Due to the updates to AP-42, Chapter 7, the EPA no longer supports or updaes the EPA TANKS 4.09d software program. TANKS 4.09d will be an acceptable determination method for RY 2019, but will be phased out in the future. For RY 2019, EPA TANKS 4.09d can be used to estimate annual EI emissions from unheated tanks that store ambient temperature products, and do not have significant throughput variation. For annual emi¬ssions, choose “Monthly” time basis and select all 12 months of the year. Never use default information unless it is representative of content and use the “detailed” option for tank fittings. TANKS 4.09d cannot be used to determine ozone emissions, landing loss emissions, or emissions from heated tanks.

The TCEQ also specified the following clarifications for the updated AP-42 Chapter 7 equations:

  • For insulated and heated tanks, modify the Chapter 7 standing loss equations to determine breathing emissions by replacing 365 days with the number of annual heating cycles and replacing the daily ambient temperature range (ΔTA) with the product's temperature range
  • For tank fittings and chemical data, do not use the default or typical number found in AP-42 or EPA TANKS 4.09d, instead use tank-specific information from operations data
  • For chemical data, do not use the default chemical data found in AP-42 or EPA TANKS 4.09d unless it is representative of tank contents. American Society for Testing and Materials method D 2879 can be used for determining vapor pressure of heavy liquids. American Petroleum Institute (API) data may be used if site-specific data is not available
  • AP-42 Chapter 7 uses an open vent system. If an internal floating roof tank has a closed vent system, Chapter 7 equations can be used with a default 5% reduction
  • If tanks are splash loaded, working loss calculations should be adjusted since AP-42, Chapter 7 equations were designed for submerged loading
  • Finally, API's E&P TANK tool may be used to calculate emissions, but site-specific extended analysis must be input to achieve accurate emissions. E&P TANK determines annual emissions, not ozone season rates. Refer to 2019 Emissions Inventory Guidelines, Appendix A, Technical Supplement 6 to determine ozone season emission rates with E&P TANK

If you have any questions related to these topics, please contact Trinity's Austin office at (512) 349-5800 or any other Texas Trinity offices.