Do environmental receptors include areas that are not Federal Class I areas?

Do environmental receptors include areas that are not Federal Class I areas under the CAA?

Yes. The list of environmental receptors in Part 68 includes areas in addition to those that qualify as Federal Class I areas under CAA section 162. Under Part 68, national parks, monuments, wilderness areas, and forests are environmental receptors regardless of size. State parks, monuments, and forests are also environmental receptors.