MassDEP Releases Its Draft Vapor Intrusion Guidance

MassDEP has recently released for public comment draft Guidance on Vapor Intrusion.   The proposed guidance would replace MassDEP's December 2011 Interim Final Vapor Intrusion Guidance, which saw minor revisions in the spring of 2013.  The guidance has undergone a substantial revision, largely to make changes that correspond to the recent regulatory reforms to the Massachusetts Contingency Plan.

The guidance provides MassDEP's recommended technical and regulatory approaches to addressing the vapor intrusion pathway at sites contaminated with releases of oil and/or hazardous materials regulated under the MCP. The issue of vapor intrusion arises when contaminants in soil and groundwater volatilize and resultant vapor-phase contaminants enter the indoor air in occupied buildings.