Oregon Revised Statutes Public Health and Safety § 468.090

(1) In case any written substantiated complaint is filed with the Department of Environmental Quality which it has cause to believe, or in case the department itself has cause to believe, that any person is violating any rule or standard adopted by the Environmental Quality Commission or any permit issued by the department by causing or permitting water pollution or air pollution or air contamination, the department shall cause an investigation thereof to be made. If it finds after such investigation that such a violation of any rule or standard of the commission or of any permit issued by the department exists, it shall by conference, conciliation and persuasion endeavor to eliminate the source or cause of the pollution or contamination which resulted in such violation.

(2) In case of failure to remedy the violation, the department shall commence enforcement proceedings pursuant to the procedures set forth in ORS chapter 183 for a contested case and in ORS 468B.032.