Phase 3 environmental site assessment being performed on a brownfield

What is a Phase 3 Environmental Site Assessment?

If you plan to purchase or invest in commercial real estate, an environmental site assessment (ESA) must be conducted. These types of assessments are considered part of the “due diligence” process and help protect your investment. ESAs can also help you determine a fair value for land (site) before you buy it.

It’s likely that you have heard about a Phase 1 ESA. You may even be aware of Phase 2 ESAs. But did you know that there are also Phase 3 environmental site assessments? If you’re unfamiliar with the third phase of ESAs, this guide is for you.

Things to Know About a Phase 3 Environmental Site Assessment

A Phase 3 environmental assessment is the most advanced type of ESA and is required when contaminants are detected in subsurface (soil, groundwater or soil vapor) during Phase 2 ESAs. During a Phase 3 ESA, assessors may perform the following actions:

  • Installing groundwater monitoring wells
  • Identify the extent of contamination by collecting soil and groundwater samples
  • Determine the volume of impacted soil and groundwater
  • Developing a remedial action plan or work plan

These efforts allow assessors to determine the severity of site contamination. Further assessment may then be required based on the findings and are mentioned below:

  • Installation of additional groundwater monitoring wells
  • Quarterly groundwater monitoring
  • Excavation and disposal of contaminated soils

The goal of these efforts is to make your land (site) safe to use. The process might take only a few weeks. However, in extreme cases, remediation can take months to perform. That is why it is important to know about the presence of contaminants before purchasing the intended property.

What’s the Difference Between Phase 1, 2, and 3 ESAs?

At first glance, all these phases can get somewhat confusing. However, the differences between the three types of ESAs are relatively straightforward. In short, Phase 1 ESAs are the least invasive. Phase 2 ESAs are slightly more so. Phase 3 ESAs are the most in-depth type of assessment.

Phase 1 ESAs check for warning signs of potential contamination. These signs are known as recognized environmental conditions (RECs). Examples include a dry cleaner facility on site or presence of underground storage tanks on site. If the Phase 1 ESA reveals RECs, a Phase 2 ESA is needed.

– During a Phase 2 ESA, the assessor will take a closer look at any RECs. They will collect soil and groundwater samples, which are sent to a lab for analysis. If lab results reveal the presence of contaminants, a Phase 3 ESA is warranted.

– Phase 3 ESAsdetermine the severity of contamination and outline a remedial action plan or work plan for remediation.

As you can see, ESAs are performed on a progressive basis. If Phase 1 reveals no presence of RECs, a Phase 2 is not necessary. If a Phase 2 ESA determines that RECs contain no actual contaminants, you will not need a Phase 3 ESA.

Phase 3 ESAs are only necessary if concerns were discovered during Phase 1 and Phase 2 ESAs. Phase 3 ESAs are designed to make properties safe for use. If contaminations are discovered, and no Phase 3 ESA is performed, the owner will incur significant liability.

What Happens After a Phase 3 ESA?

Ideally, the goal is to reduce contaminant levels to zero. However, government regulations define different minimum thresholds for each type of contaminant. Some contaminants can be present and as long as they fall below these thresholds, the site can be considered to receive closure from the state agency.

If the remediation efforts did not lower contaminants below the set thresholds, further assessment would be necessary. This process is repeated until the land (site) is made safe for use.

Learn More About Phase 3 ESAs

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