The purpose of the Phase I Environmental Site Assessment (ESA) is to identify potential areas of contamination or environmental liability associated with a property. A Phase I ESA can be conducted for several reasons. Some of these reasons are 1) qualify for one of three Landowner Liability Protections: Bona Fide Prospective Purchaser, Contiguous Property Owner, or Innocent Landowner on CERCLA Liability (federal liability protection), 2) qualify for liability protection offered through the State of Michigan by Baseline Environmental Assessment (BEA), 3) satisfy lender requirements, 4) identify if environmental conditions exist on a property for any transaction, 5) part of requirements for grant funding or Brownfield credits.


  • Site inspection (includes the entire property and visual observation of adjoining properties from the property and public access areas).
  • Research state and federal databases.  The databases meet the AAI requirements for search listings and distances and include leaking underground storage tanks, hazardous waste generators, hazardous wastes sites, and landfills.
  • Review of files maintained by the DEQ as deemed necessary from a review of the researched data- base.
  • Review of municipal records for the Property and adjoining properties as deemed relevant in identifying recognized environmental conditions.
  • Review of available historical sources (aerial photographs, fire insurance maps, city directories).
  • Geologic and hydrogeologic review to evaluate potential contaminant migration pathways and expo- sure routes.
  • Interviews with the property owner, past Property owners, occupants, and persons knowledgeable of the property.
  • A questionnaire and/or interview is completed by the User of the Phase I ESA and reviewed.
  • AAI states that a title search can be completed to close gaps in past property use/ownership.
  • Search for environmental liens.
  • Non-scope services are often completed with a Phase I ESA such as asbestos-containing materials, lead-based paint, mold, radon, wetlands, vapor intrusion, etc.


ASTI has provided due diligence services including Phase I ESAs since 1985. Our expertise in due diligence includes working with lending agencies, municipalities, grant programs through the EPA, and with State and Federal Agencies including the Michigan State Housing Development Authority and the U.S. Department of Housing and Urban Development. ASTI will provide the expertise needed to obtain environmental liability protection for your property transaction.

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For more information about Site Assessment Services, contact Mr. Richard Welsh at ASTI Environmental at 800.395.2784 or rwelsh@asti-env.com