Section 137.1 - Purpose and applicability(a) In general under the Oil Pollution Act of 1990 (33 U.S.C. 2701 , et seq.), an owner or operator of a facility (as defined in § 137.10 ) that is the source of a discharge, or a substantial threat of discharge, of oil into the navigable waters or adjoining shorelines or the exclusive economic zone is liable for damages and removal costs resulting from the discharge or threat. However, if that person can demonstrate, among other criteria not addressed in this part, that they did not know and had no reason to know at the time of their acquisition of the real property on which the facility is located that oil was located on, in, or at the facility, the person may be eligible for the innocent landowner defense to liability under 33 U.S.C. 2703(d)(4) . One element of the defense is that the person made all appropriate inquiries into the nature of the real property on which the facility is located before acquiring it. The purpose of this part is to prescribe standards and practices for making those inquiries.(b) Under 33 U.S.C. 2703(d)(4)(E) , this part does not apply to real property purchased by a non-governmental entity or non-commercial entity for residential use or other similar uses where a property inspection and a title search reveal no basis for further investigation. In those cases, the property inspection and title search satisfy the requirements of this part.(c) This part does not affect the existing OPA 90 liability protections for State and local governments that acquire a property involuntarily in their functions as sovereigns under 33 U.S.C. 2703(d)(2)(B) . Involuntary acquisition of properties by State and local governments fall under the provisions of 33 U.S.C. 2703(d)(2)(B) , not under the all-appropriate-inquiries provision of 33 U.S.C. 2703(d)(4) and this part.