Suzie’s Presentation: Suzie
Suzie Nawikas graduated with Geology and Journalism degrees from the University of Wisconsin Eau Claire in 2004, and has worked with H&P Mobile Geochemistry, Inc since moving to California in 2005. As a leader in the industry for soil vapor sampling and analysis, the H&P team is continually updating and improving techniques for proper sample collection of over 500 samples per month, nationwide. The practical experience gained as the lead project manager for H&P, combined with an understanding of federal and state regulations nationwide, has provided Suzie with a distinct perspective on soil vapor sampling and analytical techniques.
Presentation Abstract:
Currently, there is much debate across the country over the proper attenuation factor to use when evaluating sub-slab soil gas data. The EPA and many States are currently using a default attenuation factor of 0.03, which is resulting in extremely conservative screening levels for sub-slab soil gas. Further, the 0.03 attenuation factor is being applied to both residential and commercial structures alike, even though the database used to derive the 0.03 value was an evaluation of only residential structures.
With a goal of deriving more realistic attenuation factors, a database of sub-slab soil gas radon data and concurrent indoor air radon data was compiled to determine cross-slab attenuation factors. The samples in the database were collected over the past 10 years by certified soil gas sampling contractors from more than 100 primarily commercial buildings, and some residential structures.
The results from this compilation will be presented and compared to default attenuation factors currently being used by regulatory agencies around the country. The results should enable more realistic attenuation factors to be adopted by oversight agencies when evaluating the potential vapor intrusion risk from sub-slab soil gas data.
Suzie’s contact information: Phone: 760-804-9678 E-mail: suzie.nawikas@handpmg.com
Suzie’s Presentation Time:
Day 2: 11:15-12:00 – Sub-Slab to Indoor Air Attenuation Factors Determined from Radon Data – Suzie Nawikas, H&P Mobile Geochemistry