Oregon DEQ Seeks Public Comment: Vapor Intrusion Guidance
Request for Comment
Oregon DEQ is asking for informal comments on the draft Guidance for Assessing and Remediating Vapor Intrusion in Buildings, available on-line at
http://www.deq.state.or.us/lq/pubs/docs/cu/DRAFTVaporIntrusionGuidance.pdf.
Background
The purpose of this draft guidance is to help responsible parties, environmental professionals, and DEQ project managers make appropriate risk-based decisions about vapor intrusion into indoor air at hazardous substance cleanup and underground storage tank cleanup sites when the conceptual site model shows the potential for vapor intrusion. The draft guidance includes the following sections
Section 1: Introduction
Section 2: Outlines the decision framework for a vapor intrusion pathway evaluation
Section 3: Describes the key elements of a conceptual site model, data
quality objectives development, and investigation framework.
Section 4: Describes methods to determine whether remedial action is
necessary to mitigate vapor intrusion risks.
Section 5: Describes vapor intrusion mitigation strategies.
Appendix A: Describes the determination of screening level attenuation factors and
soil vapor risk-based concentrations
Appendix B: Describes the approach for Heating Oil Tank (HOT) sites
Appendix C: Describes three industrial case studies
Appendix D: Provides references and Web links
Appendix E: Provides an example vapor intrusion inventory form for indoor air sampling locations
DEQ has updated the spreadsheets of Risk-Based Concentrations (RBCs) to include RBCs for the vapor intrusion pathway. The updated spreadsheets also include recent changes to some exposure factors to account for early-life exposure to certain carcinogenic hazardous substances, including some petroleum constituents, and a 2009 update to the inhalation assessment methodology. http://www.deq.state.or.us/lq/rbdm.htm
Information Meeting
DEQ will provide an overview of the guidance and will answer questions starting at 2:00 pm on October 1, 2009 in the EQC-A room on the 10th floor at DEQ headquarters, 811 SW 6th Avenue, Portland, OR. The purpose of this meeting is to provide information and answer questions that help interested parties provide constructive comments on the draft guidance, and is not to take public comments. Training on the use of the guidance document will be provided once the document is finalized. Opportunity to indicate preferred training format is provided below.
Comments
Comments received by 4:00 PM on October 30, 2009, will be considered when the final version of the guidance document is prepared. A formal comment response will not be provided for this informal comment opportunity (i.e. public comment is not required by statute or rule). DEQ has found that constructive comments provided by future end-users of guidance documents can provide valuable suggestions for improving content, clarity, and readability.
DEQ also is asking for information on training preferences, specifically whether classroom training or Web-based training is preferred, once the document has been finalized and released.
Comments can be submitted by mail or e-mail to:
Ann Levine
Land Quality Division
Department of Environmental Quality
811 SW 6th Avenue
Portland, OR 97204-1390
Levine.Ann@deq.state.or.us