The Massachusetts Department of Environmental Protection (MassDEP) released, on December 14, 2010, a newly-revised draft Vapor Intrusion Guidance document, seeking public review and comment by March 1, 2011. The draft Guidance, including main text and appendices, is posted on MassDEP’s Indoor Air Guidance Project Blog.

MassDEP’s stated goal is to provide “recommendations and expectations” for approaches to vapor intrusion assessment and mitigation that would achieve compliance with the regulatory requirements of the Massachusetts Contingency Plan (MCP). The draft Guidance is intended to outline MassDEP’s view of best practices that would afford presumptive certainty of compliance with the MCP.