Oregon Revised Statutes Public Health and Safety § 466.200

(1) Whenever, in the judgment of the Department of Environmental Quality from the results of monitoring or surveillance of operation of any generator, air or water transporter or hazardous waste disposal, storage or treatment site, there is reasonable cause to believe that a clear and immediate danger to the public health, welfare or safety or to the environment exists from the continued operation of the site, without hearing or prior notice, the department shall order the operation of the site halted by service of the order on the site superintendent.

(2) Within 24 hours after the order is served, the department must appear in the appropriate circuit court to petition for the equitable relief required to protect the public health, welfare or safety or the environment and may begin proceedings to revoke the permit if grounds for revocation exist.