Vapor Intrusion Perspective and Updates – NC Division of Waste Management
The various programs of the Division of Waste Management (DWM) address the assessment, evaluation and mitigation of vapor intrusion impacts at sites across the state using the March 2018 DWM Vapor Intrusion Guidance Document, 2019 supplemental guidance for TCE Indoor Air Inhalation Immediate Action Levels and Response and program specific guidance. This presentation will provide an overview of upcoming revisions to DWM vapor intrusion guidance, development of new vapor intrusion documents and recent changes to the Department of Environmental Quality’s (DEQ) risk calculator with regards to vapor intrusion and screening levels. A brief review of DWM’s TCE supplemental guidance will be provided. When responding to sites with TCE concentrations exceeding immediate action levels, several steps must be taken as soon as possible including identifying receptors, gathering information about occupants, sampling, risk communication, coordination with other local and state government entities, immediate and long-term mitigation and ongoing monitoring. This presentation will discuss the regulatory perspective regarding obstacles, successes, specific issues and lessons learned when addressing these steps at TCE sites or other contamination sites where vapor intrusion is a concern.