All Appropriate Inquiries (AAI)

All Appropriate Inquiries, or AAI, is the federal standard for the investigation a buyer has to make before purchasing property in order to avoid liability for contamination that was already there. The EPA wrote the standard at 40 CFR Part 312. A Phase 1 Environmental Site Assessment done under ASTM E1527-21 satisfies it, which is why lenders, attorneys, and the SBA all ask for that specific report and no other.

The rule matters because of how CERCLA works. The Superfund law makes the current owner of a contaminated property liable for cleanup whether or not that owner caused the problem. AAI is the way out. A buyer who completes it before closing, and keeps up a few obligations afterward, can own contaminated land without owning the cleanup.

The Three Defenses AAI Unlocks

CERCLA offers three ways for a landowner to escape liability for contamination they did not cause, and each one requires AAI before purchase.

• Innocent landowner. For a buyer who did not know and had no reason to know about contamination at the time of purchase. AAI is how the buyer proves there was no reason to know.
• Bona fide prospective purchaser. For a buyer who knew about contamination going in. Congress added this defense in 2002 so that brownfields could change hands. The buyer completes AAI, does not contribute to the contamination, and follows the continuing obligations.
• Contiguous property owner. For an owner whose land was contaminated by a release that migrated from a neighbor. The owner has to show AAI was done at purchase and that the owner did not cause or contribute to the release.

Without AAI, none of the three apply, and the buyer is a potentially responsible party from the day of closing.

Where the Rule Came From

Congress created the requirement in the 2002 Brownfields Amendments to CERCLA and told the EPA to write a rule defining it. The EPA published the AAI rule in 2005, and it took effect in November 2006. ASTM revised its Phase 1 standard to match, and the EPA has recognized each revision since. In December 2022 the EPA issued a rule recognizing ASTM E1527-21 as compliant, and the earlier E1527-13 standard stopped qualifying on February 13, 2024. A report written to the old standard after that date does not satisfy AAI.

The Ten Components

The rule lists ten things the inquiry has to cover. Seven of them are the environmental professional's job. Three fall on the buyer.

The environmental professional handles these:

• Interviews with past and present owners, operators, and occupants of the property.
• A review of historical sources, going back to 1940 or to the first developed use.
• A review of federal, tribal, state, and local government records within set search distances.
• A visual inspection of the property and of adjoining properties.
• An evaluation of commonly known or reasonably ascertainable information about the property.
• An assessment of the degree of obviousness of contamination, given what the other steps turned up.
• A declaration, signed by the environmental professional, stating that the inquiry meets the rule and that the professional meets the qualifications.

The buyer supplies these, and the consultant asks for them in the user questionnaire:

• A search for recorded environmental cleanup liens against the property, which comes from the title company or a lien search vendor.
• Any specialized knowledge or experience the buyer has about the property or the surrounding area.
• The relationship between the purchase price and the fair market value of the property if it were not contaminated. A price far below market is a signal that the seller knows something.

A Phase 1 that skips the user questionnaire, or a buyer who leaves it blank, has a gap in the inquiry that a plaintiff's attorney will find.

The 180-Day Rule and the One-Year Limit

The rule fixes a shelf life on the inquiry. Five parts have to be completed or updated within 180 days before the purchase date: the interviews, the environmental lien search, the government records review, the visual inspection, and the environmental professional's declaration. The full inquiry has to be less than one year old at purchase.

Buyers whose closings slip past 180 days ask the consultant for an update letter. The consultant redoes the five dated tasks and issues a short supplement. Past one year, the whole Phase 1 has to be redone. Lenders apply the same windows to the loan closing, and our SBA requirements guide covers how the SBA handles them.

Who Counts as an Environmental Professional

The rule defines the person who can sign the declaration. A licensed professional engineer or professional geologist qualifies with three years of relevant full-time experience. A person with a bachelor's degree in science or engineering qualifies with five years. A person with ten years of relevant full-time experience qualifies without the degree or the license. Relevant experience means work on environmental investigations, such as site assessments, remediation, and regulatory compliance. Staff who do not meet the definition can do field work and research under the supervision of someone who does, and the qualified professional signs.

How ASTM E1527-21 Satisfies AAI

The EPA did not write a step-by-step procedure. It set performance requirements and then recognized the ASTM standard as a way to meet them. E1527-21 maps each of the ten components to a section of the Phase 1 report and adds structure the rule does not spell out, such as the definitions of Recognized Environmental Conditions and the required contents of the report. A consultant following E1527-21 produces a report that meets the rule, provided the user questionnaire and the lien search are included. Our ASTM standards guide covers what the 2021 revision changed.

A transaction screen under ASTM E1528 does not satisfy AAI. Neither does a desktop database report or a lender's questionnaire on its own.

Continuing Obligations After Closing

AAI gets a buyer in the door. Staying protected requires a few things over the life of ownership.

• Take reasonable steps to stop any continuing release, prevent a threatened future release, and limit exposure to anything already released.
• Comply with land use restrictions and institutional controls, such as a deed restriction that prohibits residential use or a requirement to keep a cap in place.
• Cooperate with anyone authorized to conduct a cleanup on the property, including granting access.
• Respond to information requests and subpoenas from the EPA or a state agency.
• Provide any legally required notices about the discovery or release of hazardous substances.

An owner who buys a brownfield under the bona fide prospective purchaser defense and then ignores a deed restriction loses the defense. A buyer who finds a REC in the Phase 1, closes anyway, and does nothing about a leaking tank on the property has the same problem. The environmental due diligence guide covers how buyers handle findings at closing.

Get Phase 1 ESA Quotes

ESAquotes connects property buyers, lenders, and attorneys with qualified environmental professionals who write AAI compliant Phase 1 ESAs nationwide. Submit the property details and firms that cover your area will send pricing and turnaround times.