On November 3, 2009 EPA released a draft of its Toxicological Review of Trichloroethylene for public comment, with comments due by February 1, 2010. External peer review has not yet been conducted. The document concludes that TCE is carcinogenic in humans by all routes of exposure. The document calculates an inhalation unit risk of 2 x 10-2 per ppm (4 x 10 -6 per ug/m3) based on kidney cancer risk. This number is twice the inhalation unit risk value used by EPA in establishing the Regional Screening Level value for TCE. The document can be found at:

On October 16, 2009 the Washington Department of Ecology Toxics Cleanup program released its draft vapor intrusion guidance for public comment. Comments were due November 30, 2009. The document covers a tiered assessment approach, mitigation, and the establishment of media cleanup levels. The document can be found at:

On September 14, 2009 the Oregon DEQ Land Quality Division released a draft Guidance for Assessing and Remediating Vapor Intrusion in Buildings. The document covers investigation guidelines, risk based evaluation, and mitigation. The comment period closed on October 30, 2009 and the draft document can be found at:

The North Carolina Department of Environment and Natural Resources Division of Waste Management issued Supplemental Guidelines for the Evaluation of Structural Vapor Intrusion Potential for Site Assessments and Remedial Actions on November 5, 2009. The document covers screening procedures and sampling guidance and can be found at:

In September 2009 the U. S. Postal Service issued vapor intrusion guidance to assist its staff in responding to VI concerns at postal facilities. The guidance suggests internal roles and responsibilities for both reactive and preventive approaches. The document can be found at:

The Twentieth Annual Association for Environmental Health and Sciences Meeting and West Coast Conference on Soils, Sediments, and Water will be held in San Diego, CA on March 15-18, 2010. EPA will be chairing an all day vapor intrusion session on March 16 where three new EPA technical documents will be discussed. There is also a petroleum vapor intrusion workshop scheduled for the evening of March 16 as well as other vapor intrusion platform sessions on March 15. The preliminary program can be found at the following link:

The Interstate Technology and Regulatory Council will be offering its two day course, Vapor Intrusion Pathway: A Practical Guideline, in Norfolk, Virginia on March 22-23, 2010. Information on the course is found at:

Vapor Intrusion Solutions, LLC, a subsidiary of EnviroGroup, has entered into an agreement with Cupolex Building Systems USA to provide technical support for customers who purchase Cupolex® aerated floor systems. Although relatively new to the US, over 500 million square feet of Cupolex have been installed in Europe, Canada, and other countries around the world to address vapor intrusion, radon, moisture, and soft or swelling soil problems.

The product consists of polypropylene forms that create a network of interconnected, dome-shaped voids below poured concrete slabs, which can be depressurized or vented more easily and sustainably than traditional sand and gravel venting layers. The arches created by the domes allow the concrete to distribute loads more efficiently than standard slabs, so that less concrete, steel, and aggregate is needed for the same load capacity. As a result, the cost of the forms can be off-set by the savings in materials and labor, while yielding a highly efficient venting system without the need for gravel layers, collection pipes, or liners to meet depressurization or indoor air criteria. Use of the product has contributed up to 5 LEED points on sustainable building projects.

The technical support services will be free to consultants, engineers, and customers of Cupolex® who wish to evaluate or use this state of the art technology. Prior to accepting this role, EnviroGroup spent a year investigating, field testing, and modeling Cupolex and have found it to be vastly superior to traditional slab-on-grade mitigation systems. In addition, the potential for passive venting is substantially increased by the low resistance of the open void to air flow. If you are interested in trying out Cupolex at your site, please don't hesitate to give us a call. Otherwise, go to: