Draft Post for Google Contam Group

[김수]

Hello everyone,

First of all, I would like to thank Mr. William Dols for kindly answering my previous question — your guidance was very helpful to me.

I now have another question related to modeling a basement level in CONTAM. If I define a zone as “Basement (B1 floor)” that is in contact with soil/ground, how should the leakage paths between the basement walls (or floor slab) and the surrounding soil be represented in CONTAM?

In the tutorials and examples I have reviewed (e.g., NIST TN 1887, CONTAMW tutorials), I have not found explicit instructions for this case. Should the leakage to the soil be:

• represented as leakage paths to the outdoor node with Cp=0 and negative height (below grade), or

• represented by creating a separate “Soil Zone” with appropriate parameters (e.g., fixed temperature, no wind pressure), and then connecting the basement zone to that soil zone via cracks?

I would greatly appreciate any advice, best practices, or references regarding how soil-contact leakage is typically modeled in CONTAM.

Thank you again, especially to Mr. Dols, for your continued support and expertise.

Best regards,
Suhan Kim

[William Dols]

Suhan,

If your goal is to model the entry of contaminants from the surrounding soil, for example, to simulate the transport of radon into a basement through the surrounding soil, a pressure-driven source could be used for this purpose.

Here are example documents that implemented such modeling.

• Emmerich, S.J., A. Gupte, and C. Howard-Reed, Modeling the IAQ Impact of HHI Interventions in Inner-city Housing 2005. NISTIR 7212: National Institute of Standards and Technology.
• Persily, A.K., Modeling Radon Transport in Multistory Residential Buildings Modeling of Indoor Air Quality and Exposure. 1993, West Conshohocken, PA: ASTM International. 226-242.

- Stuart