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All Appropriate Inquiries (AAI) and Federal Liability

All Appropriate Inquiries (AAI) [exit DNR] is a federal code (40 CFR, Part 312) promulgated by the U.S. Environmental Protection Agency that establishes standards for conducting Phase I of an environmental site assessment. All Appropriate Inquiry is commonly done prior to commercial or industrial property transactions to assess the likelihood of contamination, and to begin collecting information about the liability for cleanup if contamination is found.


Similar to Wisconsin state law, federal laws and codes do not require AAI prior to property transactions, although it is always a good idea to seek environmental information before purchasing property that was used for industry or commerce. The Superfund law (CERCLA) uses the term "all appropriate inquiry" for certain Phase I environmental site assessment that have important liability considerations in these two circumstances.

  1. A local government wishes to qualify for a federal brownfield grant or loan on property that they own, plan to purchase or formerly owned. This also applies to Wisconsin's Ready for Reuse Loan and Grant Program, which is funded by an EPA Revolving Loan Fund grant. To qualify for these funding programs, the local government must have conducted AAl prior to their purchase. For more information about federal grants, please see our Federal Brownfields Grants page.
  2. Any party, including local governments, wishes to preserve a Superfund liability defense by completing AAI prior to purchase. Under this "bona fide prospective purchaser" defense, even if AAI discovers contamination, the property owner preserves a defense against federal liability for the contamination. There is no equivalent liability defense under Wisconsin state law. For more information about Superfund, see our Superfund page.

Contents of All Appropriate Inquiry

EPA now recognizes both ASTM International's E1527-13 "Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process" and ASTM E2247-08 "Standard Practice for Environmental Site Assessments: Phase I Environmental Site Assessment Process for Forestland and Rural Property" as compliant with the all appropriate inquiries regulation. Either of these ASTM International Phase I standards may be used to satisfy the statutory requirements for conducting all appropriate inquiries under the Comprehensive Environmental Response, Compensation and Liability Act (CERCLA).

The EPA has established the following standards for completing AAI.

  1. An inquiry by a qualified environmental professional, including a professional opinion on whether the inquiry identified conditions that indicate discharges of hazardous substances on or near the property;
  2. Interviews with past and present property owners, facility operators and occupants to gather information about the potential for contamination;
  3. Review of historic documents such as the chain of title, aerial photos, building and land-use records to determine use and occupation of the property since its initial development;
  4. Searches for recorded environmental cleanup liens filed under federal, state or local law;
  5. Review of federal, state and local government records for waste disposal, underground storage tanks, hazardous waste management and spills on or near the property;
  6. Visual inspections of the property and adjoining properties;
  7. Review of any specialized knowledge or experience on the part of the person(s) seeking a Superfund liability defense;
  8. The relationship between the current purchase price and the value that the property would hold if not contaminated;
  9. Any other commonly known or reasonably ascertainable information about the property; and
  10. The obviousness of contamination or likely contamination, the ability to detect contamination by appropriate investigation and gaps in the data that affect the ability to interpret the data.

Qualifications to conduct all appropriate inquiry

Under EPA's AAI rule, an environmental professional is defined as someone with sufficient education, training and experience to exercise professional judgment and develop opinions and conclusions. Such an environmental professional must have:

  • a state or tribal issued certification or license and three years of relevant full-time work experience; or
  • a Baccalaureate degree or higher in science or engineering and five years of relevant full-time work experience; or
  • ten years of relevant full-time work experience.