Environmental due diligence: What is a REC in a Phase I Environmental Site Assessment?


DueDiligence emial

A phase I is the best insurance at finding out what you might be getting themselves into before you complete the transaction. It also limits your liability, if something be discovered later that you were unaware of. A Phase I site assessment just makes good business sense, and should be part of everyone’s environmental due diligence process.

The main purpose of a Phase I is to evaluate the presence of a Recognized Environmental Condition (REC) at or near the property.

A Phase I site assessment is conducted to look for releases to the environment, or potential releases to the environment – of hazardous substances or petroleum products on or in the vicinity of the property in question. These releases would be a Recognized Environmental Condition (REC).

A REC does not mean there is confirmed contamination, simply that it is possible. A Phase I ESA identifies RECs, and the report may recommend a Phase 2 ESA be conducted to confirm and evaluate the presence, amounts and effects of contamination on site and threat of a release to the environment.

Recognized Environmental Condition Definition as per ASTM

The ASTM E1527-21 standard defines a recognized environmental condition (RECas: The presence or likely presence of any hazardous substance or petroleum product on a property under conditions that indicate an existing release, a past release, or a material threat of a release of any hazardous substances or petroleum products into structures on the property or into the ground, groundwater, or surface water of the Subject Site.  

To simplify, a REC is the existence or probable existence of a hazardous substance within a property, under one or more of three ASTM-defined scenarios.

  • The REC is due to a release into the environment.
  • The REC is under conditions indicative of a release to the environment.
  • The REC poses a significant threat of a forthcoming release to the environment.

Most people associate RECs with leaking Underground Storage Tanks (UST) that were not properly closed, or property that was once a dry cleaner or a car repair shop, where toxic chemicals may have been used and not disposed of properly. However, RECs aren’t limited to just these types of properties.

Some examples of commonly seen RECs are:

  • Historical gasoline stations facilities where underground storage tanks.
  • Auto repair shops typically utilize and store hazardous substances.
  • Current and historical dry cleaning businesses operating on-site.
  • Historical plating facilities where chromium, other metals, solvents and degreasers have been utilized.
  • Foundries, manufacturing facilities, or other heavy industrial complexes.

Are you looking into a Phase I, or concerned about the results?
RSB has conducted thousands of Phase I environmental assessments across the US.
To learn more click here or give us a call at 832-761-4559 / info@rsbenv.com.