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USDA Forest Service
1400 Independence Avenue SW
Washington, D.C.
(202) 205-8333

Forest Service Air Management

Above: Idaho and Oregon's Hells Canyon Wilderness


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

Protection of Class I federal and tribal lands is specifically enabled through Prevention of Significant Deterioration (PSD) provisions of the Clean Air Act. For detailed information about the Clean Air Act, visit: http://www.epa.gov/air/caa/.

The 1964 Wilderness Act identified management goals for all wilderness areas, both Clean Air Act Class I and Class II wildernesses. State legislation and PSD regulations determine how the air quality regulatory process is actually conducted state by state.

Other laws and regulations such as the National Environmental Policy Act 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. The relevant laws are summarized below.

Relevant Laws and Regulations Summary

Prevention of Significant Deterioration (PSD) Program

The PSD sections of the Clean Air Act require a permit program for certain new or modified sources of air pollution. One primary 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. Before the construction of certain new air pollution sources is approved, the applicants must receive a PSD permit from the appropriate air regulatory agency. The Forest Service manager must make three decisions:

  • What are the sensitive air pollution receptors within the wilderness that need protection?
  • 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

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 evaluate air pollution effects on air quality related values (AQRVs) and to provide State permitting authorities and potential permit applicants consistent guidance regarding assessment of new and existing source impacts on AQRVs. Click here to view the 2010 FLAG guidance.

Best Available Control Technology Review for New or Modified Pollutant Sources

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 air quality related values (such as visibility) of federally-protected wilderness areas. The FS provides these comments to the permitting authority, typically the state.

One key part of the air permit application, required by various regulations, is a review of the air pollution control technology proposed on new or modified emission units at the facility. The air quality 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 is conducted by engineers who analyze 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.

Forest Service Conformity with National Ambient Air Quality Standards

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:

[photo] Fire fighters
  • 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 http://www.epa.gov/ttn/oarpg/genconformity.html

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 are often part of the State Implementation Plan.

Forest Service Responsibilities under the Regional Haze Rule

[photo] Two photos of same landscape showing comparison between clear blue sky and haze

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, works closely with the states, interested tribes, EPA, and the Regional Planning Organizations in the development of the technical products and policy documents that are used by each state as they develop and revise their plans. 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. To see the comments and other information regarding State SIPs submitted by the Forest Service, National Park Service and US Fish and Wildlife Service, please visit http://www.fws.gov/refuges/AirQuality/rhr.html. 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 Wilderness Act

[photo] Horseback riders in wilderness

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"

[graphic] USDA logo, which links to the department's national site. [graphic] Forest Service logo, which links to the agency's national site. [graphic] A link to the US Forest Service home page.