Due Diligence

Environmental due diligence serves as the foundation for successful development and construction. Along with positioning clients for landowner liability defenses under Superfund, our due diligence assessments help clients secure financing, reduce the risk of unexpected construction costs, and enhance the marketability of real estate investments. 

Now that we're together, we provide our clients a nationwide due diligence practice, supported by a full suite of environmental, geotechnical, ecological, water, and construction management services. Combined, our team has decades of experience with Phase I and Phase II Environmental Site Assessments, Property Condition Assessments, SBA RSRAs, & ASTM transaction screens.



Deep Local Knowledge, National Reach


ASTM Training

David Vieau and Sean Leary are two of only a handful of professionals engaged by ASTM as national instructors of the Standards for Phase I and Phase II environmental site assessments.

GZA draws on decades of experience in engineering and remediation, offering a deep local knowledge of both the physical and regulatory environment across the nation. This allows us to efficiently study a portfolio of properties, locate potential areas of concern, and expediently respond to our client's needs. You can depend on us to keep our clients' objectives front and center and to make your goals our mission.


Sean Leary

Associate Principal/VP – Transaction Risk Management