CLEAR/CURES Research Seminar: Bryan VanDuinen, PE (Geosyntec Consultants) - November 13, 2025

Value of the Information & Strength of the Argument

The seminar provides valuable insights into the complexities of vapor intrusion assessment, offering practical solutions that are not widely known. The argumentation is solid, grounded in the speaker’s extensive field experience and supported by references to EPA studies and real-world case studies. The presentation logically progresses from basic concepts to advanced techniques, making it accessible to a technical audience. The use of attenuation factors as a central theme helps clarify the decision-making process. The speaker effectively argues that conventional sampling methods may be inadequate and that innovative tools like BPC and HVS can provide more reliable data. The case study adds credibility, showing real applications. However, the presentation is an expert opinion rather than a systematic review, and some claims could benefit from more detailed data or peer-reviewed references.

Scientific Rigor, Source Quality, Title Accuracy

The seminar demonstrates strong scientific rigor, with the speaker referencing the EPA’s empirical study on attenuation factors and Michigan EGLE guidance. The sources are credible, though not explicitly cited with URLs in the presentation. The title accurately reflects the content, as it is a research seminar by a professional engineer. The content aligns well with the title, focusing on vapor intrusion assessment. The speaker’s credentials and the hosting by a university research center enhance the reliability. However, the presentation does not provide a comprehensive literature review, and some technical details are simplified. The adequacy between title and content is high, with no significant discrepancies.

The title accurately reflects the content: a research seminar by a professional engineer on vapor intrusion assessment.

8/10

The speaker is a professional engineer with 13 years of experience in vapor intrusion assessment, and the seminar is hosted by a university research center. The content is based on established EPA studies and practical case studies, though it is an expert opinion rather than a peer-reviewed presentation.

Markers derived by PSI from the transcript: the creator did not define chapters.

• 02:00Introduction to vapor intrusion and the presentation outline.
• 05:00Explanation of the lateral inclusion zone and screening distances for petroleum vs non-petroleum contaminants.
• 10:00Discussion of conventional sampling methods: sub-slab soil gas and indoor air canisters.
• 15:00Introduction to attenuation factors and the EPA empirical study.
• 20:00Challenges: background sources of contaminants in indoor air.
• 25:00Temporal variability in indoor air concentrations, with example from Arizona State study.
• 30:00Spatial variability in sub-slab soil gas, with example from a large commercial building.
• 35:00Preferential pathways like sewers and their impact on vapor intrusion.
• 40:00Introduction to building pressure control (BPC) and blower door technique.
• 45:00Case study from Michigan demonstrating the application of innovative tools.

• EPA empirical study on attenuation factors — Referenced as the basis for default attenuation factors used by regulatory agencies.
• Michigan EGLE vapor intrusion guidance — Mentioned as the framework for VI investigation in Michigan.

• EPA's Vapor Intrusion website — Provides general information on vapor intrusion and regulatory approaches.