What is the Difference Between a Phase I and Phase II Site Assessment?

Almost all commercial property that is purchased in the United States requires at the very minimum a Phase I Environmental Site Assessment (ESA). This assessment helps buyers and lenders understand the potential risk involved when purchasing a property. 

 A Phase I ESA is a good place to begin as it  will  identify any possible environmental contamination concerns. Following on from this, a Phase II Site Assessment further acts upon the concerns of the Phase 1 ESA through actual soil and groundwater testing.

Some small portion of Phase I ESA’s will likely result in a recommended Phase II; however, the client always has the choice to move forward with a Phase II or not. 

Both types of assessments are useful,  either on their own and/or in combination, so Mill Creek Environmental believes understanding the differences can help lenders, buyers and owners make smart choices. 

The Phase I ESA

  • Assesses the likelihood that a site is contaminated through regulatory records, visual observations and historical use reviews
  • Visual inspection of adjoining properties and regulatory records reviews
  • Interviews with current property occupants, owners and government officials
  • Visual inspection of the property’s current state and use compared to the site plans 
  • Can include Wetland, Endangered Species and Ecological Species Identification that could prevent certain land uses
  • Can include Asbestos, Lead Based Paint, Mold and Radon testing if desired 

End Goal: Assesses the potential presence that the property has been contaminated.

The Phase II ESA

  • Assesses whether contamination and/or soil gas is in fact present 
  • Compares lab results with the federal, state and local regulatory guidelines 
  • Uses soil and groundwater sampling to determine if any contamination is present

End Goal: Assesses IF  the presence of  contamination exists within the subject property. 


Choose Mill Creek Environmental for Your Environmental Site Assessments 

Overall, the main difference between a Phase I and Phase II Site assessment is that a Phase I is a non-invasive  visual inspection and research scope of work versus  a Phase II which assesses  if contamination is in fact present through soil and groundwater testing. 

We hope that Mill Creek Environmental has helped you understand the main differences between each of these environmental site assessments. 

To find out how Mill Creek Environmental can assist  you  with your commercial property projects and site assessments – contact us today at  706-579-1607 for a free consultation and quote.