Glossary
Phase I Environmental Site Assessment
The standard investigation into whether a property carries evidence of contamination, performed before acquisition.
A Phase I Environmental Site Assessment is a non-invasive investigation — records review, regulatory database search, historical aerials, site reconnaissance and interviews — intended to identify recognized environmental conditions on a property. It involves no sampling; where it finds something, a Phase II with actual soil or groundwater sampling follows. Beyond identifying risk, a properly conducted Phase I supports the innocent landowner and bona fide prospective purchaser defenses, which is why lenders generally require one and why it should be completed inside the feasibility period rather than after.