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Vapor Intrusion

Vapor Intrusion Database

The Vapor Intrusion Database contains data to support site-specific estimates of vapor attenuation, or the reduction in vapor concentrations as vapor-forming chemicals move from soil and groundwater into indoor air.

Please note that EPA most recently updated this database in 2012.

For your convenience, a User's Guide is provided as the first tab of the Excel® file.

Note: This file contains macros and you must have an authorized copy of Microsoft Excel® in order to open it. When opening this file the user will be asked to either enable or disable macros. The user must select "Enable Macros." If the security level on the user's computer is set to "High," macros will be automatically disabled. The user can adjust the security level for Excel® as follows:

  1. Open the Excel® application.
  2. Click on the Tools menu and select "Macro" and then "Security."
  3. An "Options" window will pop up. In this window, click on the "Security Level" tab.
  4. In the Security Level tab, select "Medium."

If the user has opened the file before adjusting the security setting, the user will need to close application and then reopen it after adjusting the security settings in order to use the marcos.

The database and estimates of site-specific vapor attenuation are further described and documented in a technical report.

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