Connecticut Department of Energy & Environmental Protection

Connecticut's Management of Toxic Air Pollutants

What Connecticut Is Doing About Air Toxics

There are a number of programs in Connecticut that address air toxics. In addition to the programs which address emissions from stationary sources, such as the state air toxics control regulation, the Air Toxics Program of the 1990 Clean Air Act Amendments and the air toxics monitoring program, there are programs which address emissions reductions from mobile sources as well as the Small Business Assistance Program.

Connecticut Air Toxics Control Regulation: In 1986, recognizing that toxics was an important air quality issue, Connecticut adopted the most comprehensive regulation, at the time, in the United States to control toxic air pollutants. This regulation established emission limits for 850 chemicals based on national occupational health standards. These substances were regulated or addressed by the Occupational Safety and Health Administration, American Congress of Government Industrial Hygienists, and the National Institute of Occupational Safety and Health. The occupational standards were used to establish both 30-minute and eight-hour emission limits. Stationary sources must comply with the emission limitations in the regulation (Regulations of Connecticut State Agencies, Section 22a-174-29). Compliance with these limitations is verified through engineering calculations, periodic testing and inspections conducted by the Department's enforcement staff.

1990 Clean Air Act Amendments: The 1990 Clean Air Act Amendments identified 174 types of facilities or source categories (e.g. chromium electroplaters, dry cleaners, or wood furniture manufacturers) that emit one or more of the 188 toxic air pollutants identified in the Act. The act directed EPA to develop standards that require stringent controls known as maximum achievable control technology or MACTs for sources that emit, or have the potential to emit, any of the listed pollutants.  These controls are implemented through the Title V Operating Permits Program for major sources. Since 1990, several of the source categories have been combined or deleted. By mid-2005, the EPA has issued 96 standards covering 174 source categories and is working to adopt the remaining standards.

Following implementation of these initial rules, a subsequent phase of rule making was to follow which could require additional pollution controls if it was determined that an unacceptable risk to human health or residual risk, remained for each source category.

Now that the initial phase of this new strategy focused on larger, higher emitting major sources is largely completed, EPA is now switching its focus to completing rules for smaller area, or minor, stationary sources with lower emission levels, sometimes called "area sources".  As part of EPA's Integrated Urban Air Toxics Strategy (Strategy) EPA will develop a total of 70 area source MACTs.  To date, EPA  has promulgated 15 standards, with an additional 25 area source MACTs currently under development and 55 standards remaining to be addressed.  This Strategy is directed at localized sources and focuses on chronic exposure. EPA intends to develop and implement the Program with input from state and local agencies.

Following the passage of the 1990 Clean Air Act Amendments, with its MACT requirements, the Department decided to retain the existing state regulation for control of air toxics as well as to implement the required federal MACT program. The driving forces behind this decision include:

  • The state regulation is health based and may be more protective of public health than the federal technology-based MACT rules.

  • The state regulation covers 850 chemicals while the MACT rules cover only 188.

  • The ability to address localized impacts, specifically the concentration of a toxic air pollutant at the property lot line, an important issue for urban equity consideration. MACT rules are strictly based on technology.

  • The state regulation applies to all sources, while the MACT rules apply to only a limited number and size of source categories.

CT's Management of Toxic Air Pollutants | Compliance Assurance

Content Last updated November 2005