2022 International Radon and Vapor Intrusion Symposium

A SIMPLIFIED APPROACH FOR CALCULATING RADIUS OF INFLUENCE OF A RADON MITIGATION SYSTEM
Darius Mali (P.Eng, C-NRPP)*, Lisa Goode , Paul Nicholson
Geosyntec Consultants
Seattle, Washington, USA
DMali@Geosyntec.com
Abstract
Geosyntec developed the high volume sampling (HVS) method a decade ago (McAlary, 2010) and since that time we have conducted hundreds of HVS tests. Geosyntec has a large data set, from a variety of sites that has been evaluated using a model that can calculate a radius of influence of a mitigation system. The presentation will describe a new simplified method to calculate a mitigation systems radius of influence and building-specific attenuation factors using data collected during pressure-field extension testing. This involves three simple measurements; extraction flow rate, cross-slab applied vacuum at a radial distance of 3 feet and cross-slab applied vacuum at a radial distance of 10 ft.   2018). The intent is to provide a practitioner with a rapid and useful screening level assessment of whether a more detailed mathematical analysis of the flow and vacuum data (McAlary, 2018) for a mitigation system would be beneficial.