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William W. Mast, P.G.

Mr. Mast is a Registered Geologist in California and a Hydrogeologist/Civil Engineer with 26 years of experience in soil and groundwater investigations and remediation, and hazardous and solid waste management. He has been the project manager, task manager, and project hydrogeologist/engineer responsible for development, implementing, and reporting the results of site assessments, Remedial Investigations, and remediation projects.

Mr. Mast's primary responsibilities have included the following:

  • Project manager on numerous real estate transfers and/or refinancing assessments including all aspects of preliminary site assessments and subsequent site investigations on properties with environmental contamination;
  • Project manager for numerous hazardous waste site investigations. Projects have included characterization of soil and groundwater contamination and development of site conceptual models to evaluate remediation strategies;
  • Project manager for several hazardous waste site remediation projects. Responsibilities included development of remediation approach, permitting and planning, contractor selection and contract negotiation, and field supervision; and
  • Project manager for several underground storage tank projects involving permitting, monitoring system design and installation, and tank removal and soil excavation.


Daniel A. Balbiani, P.E.
Robert S. Creps, P.E.
James P. Dunn, P.G.
Kyle S. Flory, P.G.
Susan E. Gahry, P.E.
William W. Mast, P.G.
Carl J. Michelsen, P.G., C.HG.
Keith O’Brien, P.G., C.HG.
Nicholas C. Pogoncheff, P.G.


Peter D. Gorman, C.HG.
William Haldeman, L.G.
Kris McCormick, CAC, REA
Brian O’Neal, P.E.
Chris J. Baldassari, P.G.
Scott Morrison, P.E.
Gary Thomas, P.G.
Mark Winters, R.G.

Senior Personnel

Matthew Dahl, P.E.
John Alexander
Justin Patterson

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