ENV-03-121 Indoor Air Quality Evaluation – Case Studies of Potencial Vapor Intrusion Pathway

Description:

Historically, the primary concern over vapor intrusion from contaminated soil and groundwater was related to the accumulation of explosive vapors. As the science and technology to measure contaminants and assess their risk has advanced, industry and regulators have learned that low concentrations of vapors from contaminated soil or groundwater may be present in indoor air. As a result, the need to evaluate the potential risk to human health has gained much attention. In response to that concern, in the November 29, 2002, Federal Register (Vol. 67, No. 230), the U.S. Environmental Protection Agency (EPA) announced the availability of a draft guidance document addressing the evaluation of the ''vapor intrusion pathway.'' The draft guidance is intended to provide a tool to help both regulators and the regulated community conduct a screening evaluation of indoor air quality. If vapor intrusion to indoor environments is identified as a possible exposure pathway, the guidance then provides a method to determine whether an unacceptable risk to human health could be present.