United States Environmental Protection Agency Region 10 April 2005 Fact Sheet Rule for Limiting Visible Emissions (40 Code of Federal Regulations Part 49 Section 124) Federal Air Rules for Indian Reservations in Idaho, Oregon, and Washington What is the FARR? The Federal Air Rules for Indian Reservations in Idaho, Oregon, and Washington, also called the FARR, is a set of air quality regulations established under the Clean Air Act. The FARR creates rules to manage activities that cause air pollution. The FARR applies to all residents (both tribal members and non-tribal members) and businesses located within the exterior boundaries of reservations in Idaho, Oregon, and Washington. The ownership status of land on the reservation does not affect how the rules apply. What will the FARR do? The FARR will protect human health and the environment for 200,000 people on reservations in the Pacific Northwest. The FARR will also: • Establish federal air quality rules where EPA- approved state or tribal air quality programs do not exist • Make air quality standards on reservations consistent with standards off of reservations • Build capacity for tribes to develop tribal air programs. Fact Sheet Series The FARR includes 16 rules that address various air quality issues: 49.122 Partial Delegation of Administrative Authority to a Tribe 49.124 Visible Emissions 49.125 Particulate Matter 49.126 Fugitive Particulate Matter 49.127 Woodwaste Burners 49.128 Particulate Matter Emissions from Wood Products Industry Sources 49.129 Sulfur Dioxide 49.130 Sulfur Content of Fuels 49.131 Open Burning 49.132 General Open Burning Permits 49.133 Agricultural Burning Permits 49.134 Forestry and Silvicultural Burning Permits 49.135 Emissions Detrimental to Public Health or Welfare 49.136 [Reserved] 49.137 Air Pollution Episodes 49.138 Registration of Air Pollution Sources and Report of Emissions 49.139 Rule for Non-Title V Operating Permits What is the purpose of this rule? The purpose of the Rule for Limiting Visible Emissions is to set limits for visible emissions produced by certain air pollution sources that operate within an Indian reservation. Visible emissions occur when particulate matter is present in an amount large enough to be seen by the human eye. Visible emissions include particulate matter. Particulate matter is a mixture of solid particles and liquid droplets that is in the air. Meeting these limits will help make certain that emissions of particulate matter are reduced and that pollution controls and process equipment are maintained and operated properly. Why is this rule important? High levels of visible emissions mean that air pollution sources are being managed and controlled poorly. These high levels can affect human health and public safety. High levels of particulate matter emissions can affect human health by increasing cases of respiratory disease such as asthma and respiratory infection. Public safety can be affected in cases where extremely high levels of visible emissions may block the sight of motorists and equipment operators. To whom does this rule apply? This rule is for each of the 39 Indian reservations in Idaho, Oregon, and Washington specified in the FARR. The rule applies to anyone who owns or operates an air pollution source that produces particulate matter or other visible air emissions. This rule does not apply to: • Open burning. • Agricultural activities. • Forestry and silvicultural activities. • Non-commercial smokehouses. • Sweat houses or lodges. • Smudge pots. • Furnaces and boilers that are used only to heat residential buildings that have four or fewer apartments or housing units. • Fugitive dust from roads owned or maintained by any federal, tribal, state, or local government. (Fugitive dust is particulate matter released into the air by wind or other similar forces.) • Emissions from burning fuel in mobile sources, such as motor vehicles, non-road vehicles and engines, locomotives, and marine (water) vehicles. ------- Fact Sheet-Rule for Limiting Visible Emissions Page 2 What are the requirements of this rule? This rule sets limits on visible emissions. The rule also describes certain cases when an air pollution source can exceed these limits. Finally, this rule specifies the methods that an air pollution source can use to show that the visible emissions limits are being met. The limit on visible emissions is 20 percent opacity over any consecutive 6 minute period. Percent opacity is the percentage of a background scene that an air pollution source blocks. A plume of smoke or dust from a chimney or pipe is an example of an air pollution source. Zero percent opacity would be a clear plume that does not block any of the background scene. One hundred percent opacity would be a plume that blocks the background scene completely. The rule allows two exceptions to the 20 percent opacity limit: • Exception 1. The limit may be exceeded if the only reason that the limit cannot be met is because of the presence of water or steam in the visible emissions. • Exception 2. The visible emissions from an oil-fired or solid fuel-fired boiler that continuously measures opacity with a continuous opacity monitoring system, also called COMS, can exceed the 20 percent opacity limit during start-up, soot blowing, and grate cleaning. This limit can be exceeded for a single time period of up to 15 consecutive minutes in any 8 consecutive hours. However, the opacity cannot exceed 60 percent at any time. The rule allows two ways, also called reference methods, for the owners or operators of air pollution sources to determine whether the visible emissions limit is being met. The first reference method for determining opacity is called EPA Reference Method 9. This method is described in 40 Code of Federal Regulations (CFR) Part 60 Appendix A. The second, or alternative, reference method for determining opacity is the use of a COMS. The COMS must comply with Performance Specification 1 found in 40 CFR Part 60 Appendix B. When does this rule take effect? This rule is effective June 7, 2005. The final rule was published in the Federal Register on April 8, 2005 (67 FR 18074). ------- |