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Risk Assessment

User's Guide for Evaluating Subsurface Vapor Intrusion into Buildings

This revised version of the User's Guide corresponds with the release of Version 3.1 of the Johnson and Ettinger (1991) model (J E) spreadsheets for estimating subsurface vapor intrusion into buildings.

EPA’s Office of Superfund Remediation and Technology Innovation is currently revising its spreadsheets for implementing the Johnson and Ettinger model described below.
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