Oregon Revised Statutes Public Health and Safety § 465.257

(a) The amount of hazardous substances contributed to the facility;

(b) The degree of toxicity or hazard posed by the hazardous substances to public health, safety and welfare, and to the environment;

(c) The degree of involvement in the release of the hazardous substance by the liable persons;

(d) The relative culpability or negligence of the liable persons;

(e) The degree of cooperation by the liable persons with the government or with persons who have a financial interest in the facility;

(f) The extent of the participation by the liable person in response actions at the facility;

(g) The length of time the facility was owned or operated by the liable person during the time the release occurred;

(h) Whether the acts or omissions that resulted in a release were in material compliance with applicable laws, standards, regulations, licenses or permits;

(i) The economic benefit derived from the facility or from the acts or omissions that resulted in a release;

(j) The circumstances and conditions involved in the facility's conveyance, including the price paid and any discounts granted; and

(k) The quality of evidence concerning liability and equitable shares.