(a) Purpose. The purpose of this section is to provide standards and practices for “all appropriate inquiries” for the purposes of CERCLA sections 101(35)(B)(i)(I) and 101(35)(B)(ii) and (iii).

(b) Applicability. The requirements of this part are applicable to:

(1) Persons seeking to establish:

(i) The innocent landowner defense pursuant to CERCLA sections 101(35) and 107(b)(3);

(ii) The bona fide prospective purchaser liability protection pursuant to CERCLA sections 101(40) and 107(r);

(iii) The contiguous property owner liability protection pursuant to CERCLA section 107(q); and

(2) persons conducting site characterization and assessments with the use of a grant awarded under CERCLA section 104(k)(2)(B).

(c) Scope. (1) Persons seeking to establish one of the liability protections under paragraph (b)(1) of this section must conduct investigations as required in this part, including an inquiry by an environmental professional, as required under § 312.21, and the additional inquiries defined in § 312.22, to identify conditions indicative of releases or threatened releases, as defined in CERCLA section 101(22), of hazardous substances, as defined in CERCLA section 101(14).

(2) Persons identified in paragraph (b)(2) of this section must conduct investigations required in this part, including an inquiry by an environmental professional, as required under § 312.21, and the additional inquiries defined in § 312.22, to identify conditions indicative of releases and threatened releases of hazardous substances, as defined in CERCLA section 101(22), and as applicable per the terms and conditions of the grant or cooperative agreement, releases and threatened releases of:

(i) Pollutants and contaminants, as defined in CERCLA section 101(33);

(ii) Petroleum or petroleum products excluded from the definition of “hazardous substance” as defined in CERCLA section 101(14); and

(iii) Controlled substances, as defined in 21 U.S.C. 802.

(d) Disclosure obligations. None of the requirements of this part limits or expands disclosure obligations under any federal, state, tribal, or local law, including the requirements under CERCLA sections 101(40)(c) and 107(q)(1)(A)(vii) requiring persons, including environmental professionals, to provide all legally required notices with respect to the discovery of releases of hazardous substances. It is the obligation of each person, including environmental professionals, conducting the inquiry to determine his or her respective disclosure obligations under federal, state, tribal, and local law and to comply with such disclosure requirements.