What a Phase I ESA is all about.
A Phase I (Environmental Site Assessment (ESA) identifies recognized environmental concerns (RECs). RECs are potential or existing environmental contamination liabilities. If RECs are identified in the Phase I ESA, then a sampling of soil, groundwater, surface water, soil gas, or indoor air may be necessary to confirm whether there has been a release of hazardous substances or petroleum products. Such sampling reports are known as a Phase II environmental site assessment.