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Air Quality Laws and Policy

Clean Air Act

The Clean Air Act sets standards for air quality to protect public health and welfare. The Forest Service must ensure that its activities, or activities it permits, comply with these national standards and any State and local requirements for air pollution control. States develop State Implementation Plans (SIPs) describing how they will implement the requirements of the Clean Air Act.

The Clean Air Act also charges the U. S. Forest Service as a Federal Land Manager of Class I areas, to protect air quality related values in the wilderness areas that were in existence as of August 7, 1977 larger than 5,000 acres.

Protection of Class I lands is specifically enabled through Prevention of Significant Deterioration (PSD) provisions of the Clean Air Act. Detailed information about the Clean Air Act is available from the US EPA.

State legislation and PSD regulations determine how the air quality regulatory process is actually conducted state by state.

The relevant programs are summarized below:

Prevention of Significant Deterioration (PSD)

The PSD program of the Clean Air Act describes a permit program for certain new or modified industrial sources of air pollution. One purpose of the PSD process is to aid in the protection and enhancement of air quality in national wilderness areas and other locations of scenic, recreational, historic, or natural value. If a new air pollution source is required to receive a PSD permit it must receive it before beginning construction.

The Forest Service manager must be consulted on PSD projects that “may affect” any Forest Service Class I area. When reviewing the PSD application, the manager must make three decisions:

  • What are the sensitive air pollution receptors within the wilderness that need protection (these are termed air quality related values – AQRVs)?
  • What are the concern thresholds for these receptors?
  • Will the proposed facility cause or contribute to pollutant concentrations or atmospheric deposition within the wilderness that will cause the thresholds to be exceeded?

The first two decisions are land management issues based upon the management goals for the wilderness in question. The third is a technical question analyzed by models combining proposed emissions, background levels of pollutants and the sensitivity of visibility and resources to the pollutants.

The Forest Service reviews the air permit applications for new and modified industrial facilities to ensure that their air emissions will not adversely impact the AQRVs (such as visibility) of federally-protected wilderness areas. The FS provides these comments to the permitting authority, typically the state.

Close coordination between the Forest Service and the appropriate air regulatory agency is essential in the PSD process. The Forest Service makes a determination of whether a proposed project will adversely impact Forest lands. The air regulatory agency then makes a decision to grant or deny the permit. The Forest Service, along with the National Park Service (NPS), and the U.S. Fish and Wildlife Service (FWS), formed The Federal Land Managers' Air Quality Related Values Work Group (FLAG) in order to consistently evaluate air pollution effects on AQRVs and to provide State permitting authorities and potential permit applicants the same guidance regarding the assessment of new source impacts on AQRVs. View the 2010 FLAG guidance.

Best Available Control Technology (New or Modified Pollutant Sources)

An important part of the PSD permit application is a review of the air pollution control technology proposed on new or modified emission units at the facility. The PSD regulations envisioned that it would be most cost effective to require pollution control upgrades at the time new sources are built or modified, thereby allowing plant owners to plan for these costs as part of the construction of a new plant or an overall plant upgrade.

In general, the review of air pollution control technology involves an analysis of what types of control technologies are possible for each regulated pollutant from each emission unit at the facility. Then, the best performing option is recommended unless it is deemed to be too expensive or causes other adverse environmental impacts.

This process of ensuring that the best available control technology is applied to industrial sources reduces air emissions to the lowest possible amount and minimizes air pollution impacts to the National Forests.

Regional Haze Rule

The Regional Haze Rule of 1999 requires states and interested tribes to address sources of pollution contributing to regional haze in the 156 mandatory Class I areas. To do this, states develop visibility State Implementation Plans (SIPs) to demonstrate to the public, the Federal Land Managers (FLMs) and EPA how they plan to address regional haze to reach the goal of natural background conditions by the year 2064. The Forest Service, as the FLM of 88 mandatory Class I areas, worked closely with the states, interested tribes, EPA, and the Regional Planning Organizations in the development of the technical products and policy documents that were used by each state as they developed their plans. By 2012, most plans were submitted by states to EPA. By law, the FLMs of mandatory Class I areas have a formal consultation with each state 60 days before the draft plans go to public hearing. See the comments and other information regarding State SIPs submitted by the Forest Service, National Park Service and US Fish and Wildlife Service. As stewards of the resource targeted for protection, the Forest Service has a special duty to ensure the Class I wildernesses under our responsibility are managed for the use and enjoyment of current and future generations. The next 10-year plans are due in 2018.

General Conformity

The General Conformity Rule ensures that federally funded or supported actions taken by federal agencies and departments, including the Forest Service, meet national standards for air quality in federal nonattainment and maintenance areas. Under the Federal Clean Air Act, any area that violates national ambient air quality standards for any of the six criteria pollutants is designated as a nonattainment area. These pollutants are sulfur dioxide, fine particulate matter, carbon monoxide, ozone, nitrogen oxides, and lead. Maintenance areas are any former nonattainment area that has been redesignated to attainment status and may require special measures to maintain its attainment status.

Activities that emit significant levels of criteria pollutants in a nonattainment or maintenance area are subject to the conformity rule. This rule requires the Forest Service or any federal agency to demonstrate that their action will not impede the State Implementation Plans to attain or maintain the ambient air quality standard. A few examples of activities on National Forests and Grasslands that may require a review for conformity include:

• Oil and gas or mineral development • Fuel treatments including prescribed fire and harvest activities • Road, trail, or building construction • Land use and special use permit decisions such as ski or winter sports area, mining, oil and gas development and landfills

For additional detail, please see the U.S. Environmental Protection Agency.

State Smoke Management Plans

Most states have developed plans for managing and controlling smoke from prescribed fire. A smoke management program is designed to minimize smoke entering populated areas, prevent public safety hazards (such as smoke on roads or runways), avoid national ambient air quality violations, and to avoid visibility impacts in Class I areas. Smoke Management Plans may be part of the State Implementation Plan.

National Environmental Policy Act

Other laws and regulations such as the National Environmental Policy Act (NEPA) and the National Forest Management Act influence how the Forest Service manages and protects national forests and grasslands in relation to air quality and its effects on people and resources It establishes national environmental policy and goals to protect, maintain, and enhance the environment; requires all federal agencies to examine the environmental consequences of major proposed actions, and to conduct a decision-making process that incorporates public input. Find out more about this act and Forest Service NEPA activities.

National Forest Management Act

The National Forest Management Act (NFMA) requires national forests and grasslands to create land management plans. The law states "National Forests are ecosystems and their management… requires an awareness and consideration of the interrelationships among plants, animals, soil, water, air, and other environmental factors within such ecosystems" Find out more about this act or forest planning.

The Wilderness Act

The 1964 Wilderness Act identified management goals for all wilderness areas, both Class I (protected under the Clean Air Act) and Class II. It requires wilderness areas to be administered "for the use of the American people in such manner as will leave them unimpaired for future use and enjoyment as wilderness." National Forest System Wilderness Implementing Regulations: "Wilderness Resources shall be managed to promote perpetuate and where necessary restore the wilderness character of the land". Find out more about this act and wilderness stewardship.