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Area Source Rule Implementation Guidance

EPA is required under the Clean Air Act (CAA) to identify 30 hazardous air pollutants (HAPs) posing the greatest health threat in urban areas, which EPA has identified in its Urban Air Toxics Strategy. The CAA also requires EPA to identify sufficient area source categories to ensure that area sources representing ninety percent of area source missions of the thirty urban HAPs are subject to regulations.  The purpose of this guidance is to:

  1. prioritize the area source rules to help delegated agencies and implementing regions focus their limited resources on the most significant standards to achieve emission reductions to the greatest extent possible;
  2. identify recommended approaches to ensuring compliance with individual rules; and
  3. provide delegated agencies and implementing regions flexibility to address regionally significant issues.

The guidance also addresses other implementation issues such as data reporting.

Issue date: June 4, 2010

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