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Vapor Intrusion

Conceptual Model Scenarios for the Vapor Intrusion Pathway

This report provides simplified simulation examples to illustrate graphically how subsurface conditions and building-specific characteristics determine (1) the distribution of vapor-forming chemicals in the subsurface, and (2) the indoor air concentration relative to a source concentration.  It was prepared to help environmental practitioners gain insights into the processes and variables involved in the vapor intrusion pathway and to provide a theoretical framework with which to draw inferences about and better understand the complex vapor fate and transport conditions typically encountered at actual, non-idealized contaminated sites.

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