Air toxics: controlling stationary sources

Pump jack extracting oil or gas in Colorado's Front Range

Colorado’s Air Quality Control Commission (AQCC) has adopted several regulations that directly or indirectly reduce emissions of air toxics from stationary sources. These include:

Regulation 3:

Stationary Source Permitting and Air Pollutant Emission Notice Requirements

  • Regulation 3 requires certain permit applicants to conduct an environmental justice report and summary prior to submitting their main permit application.
  • Regulation 3 also requires sources of affected pollutants in cumulatively impacted communities applying for certain permits, to develop and implement a source-specific monitoring plan. Exemptions include those for facilities where air dispersion modeling demonstrates that air toxics such as benzene, ethyl benzene, toluene, and xylenes (BTEX) are below certain cumulatively impacted monitoring thresholds. 
  • Regulation 3 also authorizes a fee on sources of affected pollutants applying for a construction permit in a disproportionately impacted community, or renewing a Title V operating permit in a disproportionately impacted community, if the facility opts out of source-specific monitoring based on air dispersion modeling. This fee would cover community monitoring projects for BTEX and other affected pollutants. 
  • Additionally, sources in cumulatively impacted communities must complete a Reasonably Available Control Technology (RACT) analysis for nitrogen oxides (NOx), particulate matter (PM2.5), and volatile organic compounds (VOCs) to identify where further air pollution emissions reductions can be achieved. Installing RACT for those emissions could also achieve reductions in air toxics.

Regulation 4:

Concerning the Sale and Installation of Woodburning Appliances and the Use of Certain Woodburning Appliances During High Pollution Days

  • Regulation 4 establishes standards for wood burning appliances and sets restrictions on when this equipment can be used in certain areas on higher pollution days. These regulations establish particulate matter emission limits and reduce air toxic emissions from wood burning, primarily formaldehyde and benzene. 

Regulation 7:

Control of Emissions from Oil and Gas Emissions Operations

  • Regulation 7 establishes standards to control and monitor emissions from the oil and gas sector and creates a greenhouse gas intensity program to reduce preproduction and production emissions. These regulations focus on controlling ozone precursor emissions such as volatile organic compounds (VOCs) and nitrogen oxides (NOx) as well as greenhouse gasses such as methane. By reducing process emissions such as combustion equipment or fugitive leaks, air toxics emissions reductions are also achieved.  

Regulation 8:

Control of Hazardous Air Pollutants

  • Regulation 8 incorporates federal air toxics regulations, also known as the National Emission Standards for Hazardous Air Pollutants (NESHAP) by reference. Each NESHAP focuses on a different sector or source of emissions. These regulations establish emission limits, work practice standards, and define the required monitoring, reporting, and recordkeeping requirements to demonstrate compliance with each rule.  

Regulation 15:

Control of Ozone-Depleting Compounds

  • Regulation 15 regulates substances that can deplete ozone in the stratosphere. Ozone depleting substances are identified as toxic air contaminants in Colorado. In addition to federal requirements, Regulation 15 includes requirements for fees, equipment registrations, facility notifications, and prohibition against intentional venting of chlorofluorocarbons by the owners and operators of certain sources, and the recordkeeping requirements for motor vehicle air conditioning repair facilities.

Regulation 21:

Control of Volatile Organic Compounds from Consumer Products and Architectural and Industrial Maintenance Coatings

  • Regulation 21 established limitations on VOC content and other chemical compounds in consumer products and architectural and industrial maintenance coatings manufactured and/or used in Colorado. Since many of the VOC in these materials are also air toxics, restricting the VOC content also reduces the air toxics from the products. In addition, these regulations directly prohibit certain air toxics in these products, such as trichloroethylene and substances that can deplete ozone in the stratosphere.