Meet Gei's

Robert Gensemer, Ph.D.

Vice President & Senior Ecotoxicologist

Dr. Robert (Bob) Gensemer is an aquatic ecologist and toxicologist deeply interested in applying the latest scientific advances to the regulation and management of ecological risks in aquatic environments. One of his primary areas of technical expertise is the development and basis of aquatic life criteria for Clean Water Act compliance, including criteria derivation and modification, site-specific criteria development, and the use and development of metals bioavailability models such as the biotic ligand model (BLM) for derivation of site-specific metals criteria. He also has substantial technical expertise in ecological risk assessment and strategic risk management, primarily at contaminated sediment remediation sites under the auspices of EPA’s Superfund program.

Since joining GEI, Dr. Gensemer has established National leadership with respect to the regulatory implementation of new bioavailability-based models for development of aquatic life criteria, such as the Biotic Ligand Model for copper, aluminum and other metals. He has also helped strengthen GEI’s technical and strategic leadership in the application of ecological risk assessment to the remediation of contaminated sediments, being a key member of utility client project teams at some of the largest and most complex Superfund remediation sites in the U.S. Most recently, he has become an active member of the PFAS Surface Water Quality team of the Interstate Technology and Regulatory Council (ITRC) working to develop new guidance related to managing the potential ecological risks of PFAS in surface waters.

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  • Author of over 35 peer-reviewed journal publications and books
  • Invited Participant: Society of Environmental Toxicology and Chemistry (SETAC ) Technical Workshop on Bioavailability-based Water Quality Criteria for Metals (2017)
  • GEI Best Project Management Team (2015): Leveraging One for the Good of the Many: Creative Thinking for the Advocacy and Application of the Biotic Ligand Model