Oregon Revised Statutes Public Health and Safety § 468A.140

(1) The Environmental Quality Commission may assume and retain control over any class of air contamination source if it finds that such control is beyond the reasonable capabilities of the regional authorities because of the complexity or magnitude of the source.

(2) If the commission does assume or retain control over any class of air contamination source under subsection (1) of this section, a regional authority may petition for the restoration or transfer of such control. If the commission finds that the reason for its assumption or retention is no longer valid, it may restore or transfer control over the class of air contaminants to the regional authority.