Brent Pautler, Ph.D. (ON) will present “Patented Quantitative Passive VOC Soil-Gas Monitoring with the Waterloo Membrane Sampler™” during the Thought Leader Webinar Series at 1:00pm EDT on June 24, 2021.

Brent’s co-presenter is Todd McAlary, Ph.D. (Geosyntec Consultants).

Brent is the Chemistry Services Manager and received his Ph.D. environmental analytical chemistry in 2013 where he gained advanced technical experience in spectroscopy, chromatography, mass spectrometry, passive sampling, and chemistry informatics. Throughout his career, he has worked with scientists, engineers, and consultants, applying his chemistry and information technology expertise to help them solve unique problems in the laboratory and the field. His role includes managing and advancing SiREM’s passive sampling portfolio, analytical testing services while supporting Photonics business development.

The Thought Leaders Webinar Series highlights the latest ideas for in situ remediation from our industry’s leading thinkers. These webinars connect you directly with these leaders so you can learn new techniques and strategies to boost your knowledge, benefit your bottom line, and serve your clients better. All webinars are taught by people who really know in situ remediation and are eager to share their knowledge. The purpose of this series to give back and help members of the groundwater remediation community earn PDHs that may not have an opportunity to attend a conference.

Tersus Environmental was founded in 2011 to provide technology-based solutions combined with unparalleled technical support to increase remediation effectiveness and decrease remediation costs. Their focus is the remediation of soil and groundwater impacted with:

  • NAPLs
  • Chlorinated Solvents
  • Petroleum Hydrocarbons
  • Per- and Polyfluoroalkyl Substances (PFASs)
  • Pesticides
  • Metals

They partner with clients to mitigate risks and deliver technology-based solutions to manage complex, challenging environmental liabilities. Their business model is to support the environmental consulting community with experience and resources to implement projects utilizing innovative and emerging technologies.


Passive sampling has been growing in popularity for the measurement of volatile organic compounds (VOCs) due to lower costs, simpler sampling protocols and ease of deployment, with applications ranging from indoor/outdoor air quality and soil vapor intrusion assessments. The Waterloo Membrane Sampler™ (WMS™), a passive permeation sampler which incorporates a polydimethylsiloxane membrane across the face of a vial filled with sorbent medium, provides additional advantages such as a high resistance to water vapor and predictable uptake rates for virtually any VOC. It has found use in collecting time-weighted average quantitative results for soil gas and vapor intrusion projects for risk assessment and/or monitor remediation projects. This presentation will provide technical information on the WMS™ and provide data on sampler developments including the use of WMS™ in soil gas sampling programs in which the design of the sampler was modified to incorporate a thicker membrane, reducing the potential for “starvation”, a common issue when collecting soil gas samples with passive samplers. The benefits relative to the conventional Summa Canister/TO-15 methods of sampling and analysis will also be introduced.

More Information

Register for the Webinar: here
About the Thought Leader Webinar Series:
About Tersus Environmental:
For consultation regarding WMS™ and quantitative soil gas passive sampling visit
or contact Brent at

Learn more about Brent:
Learn more about Todd: