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Controlling Sources of Toxic Air Pollutants

Controlling Sources of Toxic Air Pollutants

NYS has a long history of implementing programs to control toxic air pollutants. In 1957, the NYS Legislature created comprehensive air pollution control laws by passing the Air Pollution Control Act. The law recognized the need "to safeguard the air resources of the state from pollution". The law focused on controlling air pollution from existing industry and preventing new releases of air pollution. NYS' policy was and remains: "to maintain a reasonable degree of purity of the air resources of the state, which shall be consistent with public health and welfare and the public enjoyment thereof, the industrial development of the state..." By 1962, this law was the foundation for an air pollution control program to control emissions from industrial plants and from the combustion of fuels. Readers are encouraged to review EPA's "Reducing Emissions of Hazardous Air Pollutants site (leaves DEC website).

The Development of the State Program

In 1968, NYS enacted Part 212, Process Operations (leaves DEC website) to control toxic air pollutants. These emissions are from industrial processes and the burning of waste fuels. Additionally, NYS enacted Part 257 to set air quality standards for nine toxic air pollutants.

NYS' air toxic program evolved over several decades. Our knowledge grew about how air pollution affects public health and the environment. This advanced knowledge included how to assess air concentrations of air pollution and technological advances in air pollution control. These advances have resulted in the implementation of stronger air pollution abatement strategies over the years to improve air quality and to better ensure the protection of public health and the environment.

The air toxics program requires facility owners to perform an analysis to determine health impacts from inhalation exposures. This analysis requires the use of an air dispersion model. The model predicts the maximum 1-hour and annual air concentrations for each toxic air pollutant released. These concentrations are compared to Short-term (SGC) and Annual Guideline Concentrations (AGC) developed by DEC. This process and other factors are used to determine the degree of air pollution control. The guideline concentrations are updated every three years. More information can be found in DAR-1: Guidelines for the Evaluation and Control of Ambient Air Contaminants under Part 212 (PDF).

Addressing Mobile Source Pollution

Controlling air pollution from motor vehicles will improve air quality and protect public health. The 1965 Motor Vehicle Air Pollution Control Act prohibited the sale of high-emitting vehicles and the tampering of any pollution control devices. The 1970 Clean Air Act required further emission reductions that focused on the criteria air pollutants. These included carbon monoxide, nitrogen oxides and hydrocarbons. EPA's national program and California's state program are leaders in the field. The 1970 Clean Air Act (CAA) divides mobile sources into three categories:

  • on-road motor vehicles, such as cars, trucks, and buses;
  • airplanes;
  • and non-road vehicles and engines, including construction equipment, farm equipment, ships, locomotives, and tractors.

The 1990 Clean Air Act Amendments (CAAA) enabled EPA to develop further regulations that:

  • required the development of fuels that would burn cleaner.
  • targeted emissions of criteria air pollutants with new technology.
  • addressed toxic air pollutants.
  • authorized the promulgation of emission standards for non-road engines.
  • required onboard emission monitoring equipment.

The number of vehicles and vehicle miles traveled has increased, yet emissions have decreased. In 1995, the introduction of reformulated gasoline (RFG) resulted in significant decreases in ozone concentrations. Section 112(k) of the CAA deemed that RFG must be sold in certain ozone non-attainment areas. Federal rules limit the amount of benzene by volume in RFG gasoline which reduces tailpipe and evaporative emissions of benzene. RFG is required in the New York Metropolitan area (NYMA) and in Orange and Dutchess counties.

In 2007, EPA issued a more stringent rule to address releases of toxic air pollutants. The final standard lowered emissions of benzene and other toxic air pollutants by:

  • further lowering the benzene content in gasoline (lower than 1995 RFG levels).
  • reducing exhaust emission from passenger vehicles operated at cold temperatures.
  • reducing emissions that evaporate from portable fuel containers.

More history and federal programs can be found on EPA's Regulations for Emissions from Vehicles and Engines site (leaves DEC website).

New York State Air Quality

These strategies reduce toxic air pollutants from stationary and mobile sources and have resulted in significant improvements in air quality. DEC's Bureau of Air Quality Surveillance report: NYS Ambient Air Monitoring Program Network Assessment shows the success of these efforts and trends for criteria pollutants and some toxic air pollutants. The Trends for Specific Volatile Organic Compounds show historical trends for common toxic air pollutants.