What is a Phase I Environmental Site Assessment (ESA)?

A Phase I ESA is a tool commonly used in evaluating the environmental liability associated with a real estate asset of any type. Whether the property is industrial, commercial, mixed-use, and multifamily.

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Why Choose Preemptive Strike?

Our Phase I ESA Environmental Professionals have written hundreds of Phase I ESA and collectively bring over 17 years of specific Phase I experience.

Projects Completed
Inspected Buildings
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Services Provided


  • Phase I ESA
  • Peer Review

Why is it Important

chemical or fuel drums - potential source of site contamination

A Phase I ESA identifies Recognized Environmental Conditions (RECs) that are associated with the property that could impact its value.

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The actual sampling of soil, air, groundwater and/or building materials is typically not conducted during a Phase I ESA. The Phase I ESA is generally considered the first step in the process of environmental due diligence. Standards for performing a Phase I site assessment have been promulgated by the US EPA[1] and are based in part on ASTM in Standard E1527-13