The Division has recently published guidance documents and proposed rulemakings to satisfy upcoming requirements of the Public Protections From Toxic Air Contaminants Bill, House Bill 22-1244 (HB22-1244).

Background

On June 2, 2022, Colorado signed House Bill 22-1244 into law. This set the wheels in motion for Colorado to develop an air toxics program with five components:

1. Toxic Air Contaminants (TACs) reporting
2. Air toxic monitoring program
3. Air toxic emission control regulations for priority TACs
4. Health based standards for priority TACs
5. Air toxic permitting needs assessment

Per the statute, the Air Quality Control Commission (AQCC) and the Division must meet several key milestones, by no later than:

• January 2024: Establish first 3 toxics monitoring sites
  • National Air Toxics Trends Station (NATTS) were initiated in Adams County (Commerce City), Mesa County (Grand Junction), and Weld County (La Salle/Platteville).
• June 2024: First annual TAC inventory report due
  • Annual reports required for all major and synthetic minor sources by June 30th each year.
• October 2024: Develop Gap Analysis Report
  • Final report on TAC reporting gap assessment published.
• April 2025: Adopt Rule to establish five priority TACs (PTACs) and ensure annual TAC reports are submitted
  • The Division requested a rulemaking hearing for January 2025 for the proposed PTACs: acrolein, hydrogen sulfide, ethylene oxide, benzene, and hexavalent chromium.
  • The AQCC may revise air toxics reporting requirements by April 2025 for subsequent reports.
• July 2025: Establish 3 additional toxics monitoring sites
  • The Division will be taking public comment from November 2024 – January 2025 on monitoring sites to be located in Jefferson County, El Paso County, Pueblo County, and/or Fremont County.
• December 2025: Conduct a needs assessment for an air toxics permitting program for stationary sources.
• April 2026: Develop and adopt health-based standards for PTACs and emission control regulations for new and existing stationary sources to reduce emissions of PTACs, with prioritization of reductions in disproportionately impacted communities.
• Beginning September 2029 and every five years thereafter: determine whether to identify additional PTACs, whether to set acute exposure limits for PTACs, determine whether to revise the health-based standards
• Beginning September 2030 and every five years thereafter: adopt emission control regulations for any new PTACs and determine whether to revise existing emission control regulations.

Who Does it Impact, And What Can I Do?

The Division has begun to implement the requirements of HB22-1244 by collecting TAC information through new TAC reporting requirements and monitoring ambient levels of toxics through newly established ambient monitors. Additionally, the Division has proposed five PTACs which will be subject to future health-based standards and emission control regulations. Over approximately the next year, the Division will conduct a needs assessment for an air toxics permitting program.

Collectively, the requirements of the evolving Colorado air toxics program currently impact all sources subject to the Title V operating permit program and synthetic minor sources of the Title V operating permit program. There are over 2,100 facilities in Colorado that are subject to these requirements. Sources that emit one of the proposed PTACs (acrolein, hydrogen sulfide, ethylene oxide, benzene, and hexavalent chromium or a future PTAC) should expect to have additional emission reduction requirements for applicable PTACs and may require additional air permitting.

It is important to ensure air emissions data is accurate and consistent across all reporting requirements (e.g. EPA’s toxic release inventories [TRI] and the Colorado TAC report) and the data reported is in accordance with the Division’s TAC reporting requirements. These datasets are relied on and will continue to be used by the Division to propose new PTACs and for developing future emission reduction regulations and air permitting requirements.

Due to the large reach and impact of the developing air toxics program, it is also important for facilities to stay abreast of the developing rules and guidance documents and participate in the stakeholder processes. The Division has a listserv where the public can register to receive notifications on air toxics developments.

If you would like to discuss the proposed TAC requirements for Colorado and how they may impact your facility, please email Ashley V Jones in Trinity’s Denver Office or call 720.638.7647.