For the purposes of this subchapter:

(1) "Facility" means any real or personal property that is either stationary or portable and is located on one or more contiguous or adjacent properties under the control of the same owner or operator and that emits or has the potential to emit any air pollutant subject to regulation under the Clean Air Act of Montana or the Federal Clean Air Act, including associated control equipment that affects or would affect the nature, character, composition, amount, or environmental impacts of air pollution and that has the same two-digit standard industrial classification code. A facility may consist of one or more emitting units.

(2) "Portable facility" means an emitting source designated by the department in its database with the county code number "777," based on ability to move the source to other locations.

(3) "Wildland fire use" means the management of naturally-ignited fire to accomplish specific resource management objectives in predefined geographic areas. The term does not include fire on agricultural land.