Center for Leadership in Environmental Awareness and Research (CLEAR) Hybrid Seminar

Vapor Intrusion: The Complexities of Weather, Buildings, Sewers and Contamination

Presenter: Kelly Pennell, Ph.D., PE

January 25, 2024 - 12:30 to 1:30 p.m. via Zoom

The Center for Leadership in Environmental Awareness and Research (CLEAR) is pleased to invite the campus community to a hybrid webinar, "Vapor Intrusion: The Complexities of Weather, Buildings, Sewers, and Contamination," on January 25, 2024 from 12:30 to 1:30 p.m. via Zoom and at the Integrative Biosciences Center in the large 1st floor seminar room. The seminar is free; registration is required. Registrants will receive the Zoom link via email.

Kelly G. Pennell, Ph.D., PE, professor of Civil Engineering and the Earl Parker Robinson Chair in Environment and Sustainability in the Pigman College of Engineering at the University of Kentucky, and director of the University of Kentucky Superfund Research Center, will be the guest presenter.

Abstract:

The University of Kentucky Superfund Research Center (UKSRC), funded by the National Institute of Environmental Health Sciences (NIEHS), integrates multidisciplinary research, training, and stakeholder engagement around a common theme: reducing health risks posed by environmental contaminants in communities. This presentation focuses on research conducted by the UKSRC that identifies and reduces risks associated with volatile organic compounds (VOCs) that are transported as subsurface vapors into indoor air spaces (i.e., vapor intrusion). For several decades, the intrusion of radon gas has captured the attention of the environmental health community, as radon is identified as the 2nd leading cause of lung cancer in the United States. More recently, since the early 2000s, vapor intrusion of VOCs that emanate from hazardous waste sites has gained regulatory attention. VOC concentrations in indoor air are susceptible to temporal and spatial variations and have been challenging for vapor intrusion scientists to characterize. The overall vapor intrusion transport process depends on several factors such as contaminant source characteristics, subsurface conditions, building characteristics, and general site conditions. Notably, our research played a landmark role in establishing the importance of identifying alternative “preferential” pathways, such as sewers and other utility conduits, at vapor intrusion sites. This presentation will include a summary of laboratory, field, and numerical modeling data to inform vapor intrusion assessment and mitigation approaches. Research conducted in association with two superfund sites will be presented. Results from a multi-year field study conducted adjacent to the Middlefield-Ellis-Whisman (MEW) Superfund Site illustrate the importance of sanitary sewers in transporting VOC vapors, which can serve as preferential pathways expanding the nature and extent of vapor intrusion in communities. Most recently, our team collaborated with stakeholders at the MEW Superfund site to install a mitigation approach that was relevant and feasible for the community. Furthermore, results from a modeling study applied to a residential house overlying a trichloroethene (TCE) groundwater plume near the Hill Airforce Base Superfund Site demonstrate how variability in indoor air VOC concentrations can be influenced by both weather and building conditions. We used Monte Carlo simulations and compared model results to vapor intrusion field data to verify our modeling approach. The greatest TCE concentration was predicted for winter, then shoulder seasons, with the lowest TCE concentration during summer. The modeling approach used in this study provides practitioners with a cost-effective tool for evaluating variability in exposure risks (e.g., indoor air concentrations) based on weather conditions and building characteristics. Collectively this presentation will highlight the importance of accurate conceptual models and how research can directly inform policy and science-based decision making at hazardous waste sites.

Biography:

Dr. Kelly G. Pennell is a professor of Civil Engineering and Earl Parker Robinson Chair in Environment and Sustainability at the University of Kentucky, Pigman College of Engineering.  She is the Director of the University of Kentucky Superfund Research Center (UKSRC), which is funded by the National Institute of Environmental Health Sciences. UKSRC focuses on reducing health risks posed by environmental contaminants in communities. It investigates the impact of persistent halogenated organics, aims to reduce the toxic effects of these chemicals, and seeks to promote health equity in communities. Dr. Pennell is a licensed professional engineer with previous experience working for an international consulting firm. She earned her PhD from Purdue University in Civil Engineering and has published numerous peer-reviewed journal articles, advised dozens of graduate students, and influenced science-based decision making at federal and state and local levels. She is a well-known expert in stakeholder engagement, modeling fate and transport processes, vapor intrusion science, and preventing and reducing chemical exposures in communities.