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ENGINEERING FORUM TELECONFERENCE
April 2, 2008
TOPICS IN THIS MONTH'S MINUTES:
TECHNICAL PRESENTATION
TECHNICAL QUESTION
2008 NARPM CONFERENCE
WINTER 2009 TSP MEETING
MISCELLANEOUS ITEMS
TECHNICAL PRESENTATION
Peter Grant, the Division Director of Land Science Technologies (a division of Regenesis, Inc.), gave a presentation highlighting the benefits of Geo-Seal™, a composite gas vapor barrier management technology. Geo-Seal is designed to eliminate vapor intrusion at brownfields or other environmentally impaired sites, such as manufacturing facilities, dry cleaners, gasoline service stations, and landfills. Geo-Seal is a chemically resistant material that is placed between the foundation of the building and the soil pad to eliminate vapor intrusion pathways and stop contaminated vapors from permeating the slab.
The triple-layer system used in Geo-Seal provides redundancy and protection against the formation of vapor pathways both during and after installation. Such pathways can result from chemically induced materials breakdown, punctures, and seam weaknesses resulting from poor detail work, and/or application installation imperfections around penetrations. Geo-Seal also provides protection from a range of contaminant vapors, including those from petroleum-based products and chlorinated hydrocarbons.
The base layer (bottom) and the bond layer (top) are composed of a high-density polyethylene material bonded to a geo-textile on the out-facing side. High density polyethylene is known for chemical resistance, high tensile strength, excellent stress-crack resistance, and for reliable subsurface containment. The geo-textile, which is physically bonded to the chemical resistant layer, allows the bond layer to adhere to slab, and provides a friction course between the base layer and the soil. The core layer is composed of an elastic co-polymer modified asphaltic membrane which provides additional protection against vapor transmission. This layer creates an effective seal around slab penetrations and eliminates the need for mechanical fastening at termination points. Geo-Seal forms a puncture resistant barrier that greatly reduces the chance of damage occurring after installation and prior to the placement of concrete.
Geo-Seal can be installed by many certified applicators throughout the country. Cost varies depending on site conditions, project complexity, and other factors, but less complex sites average $2.50 to $3.50 per square foot, while more complex sites average $3.50 to $4.00 per square foot. Questions about this product may be directed to Peter Grant (pgrant@landsciencetech.com).
TECHNICAL QUESTION
Joe McDowell, an RPM from Region 3, has a vapor intrusion site in Pennsylvania at which the potentially responsible party (PRP) has suggested using an "enhanced" vapor barrier rather than the typical ASTM standard design. This site is being redeveloped as an office park. The developer is moving forward with plans to build two additional five-story office buildings immediately adjacent to quarries that were used for disposal of coal tar waste. The quarries will be capped and paved as part of the development/remediation integration. There are three similar, adjacent buildings that were constructed over the past several years without any vapor barrier. Because the vapor barriers would be placed on 6" of stone, Joe is concerned that the barriers may fail. The developer is proposing to use 6 mil plastic, which will be booted at any penetrations.
Harry Ball (Region 9) agreed that the PRP’s proposed solution is insufficient to mitigate the risk. He suggested that Joe inform the PRP of the potential monitoring costs if a more comprehensive mitigation system is not put in place. Ray Saracino (Region 9) recommended that Joe contact Carmen Santos in Region 9 (tel: 415-972-3360). Mike Davis (Region 7) offered to put Joe in contact with Bill Pedicino, a vapor intrusion specialist in Region 7.
2008 NARPM CONFERENCE
The 2008 NARPM conference will be held the week of July 7th in either Portland, OR, or Pittsburgh, PA. The EF has tentatively scheduled their business sessions for Monday and Thursday afternoons, although these days and times depend on the final NARPM agenda. All proposed EF training sessions have been approved. The TSP co-chairs reminded state participants that they need to forward their state’s travel approval notice to John Quander (TIFSD) before making travel arrangements.
WINTER 2009 TSP MEETING
The U.S. Geological Survey’s (USGS) Toxic Substances Hydrology Program has suggested the TSP hold a joint meeting the week of January 26, 2009. The TSP co-chairs have decided to move forward with planning this joint meeting. USGS has indicated that they are flexible regarding the timing and location of the meeting.
MISCELLANEOUS ITEMS
- Kelly Madalinski (TIFSD) is on detail to Region 10’s Portland office for the next six months. Approximately half of his time will be devoted to headquarters projects. After his detail ends, he will no longer participate on the EF calls as a TIFSD representative.
- Thanks to all EF members who commented on the draft DNAPL contaminant focus section of the Clu-In website (www.clu-in.org). The site is now available on Clu-In.
ATTENDEES
Jim Brown, Region 1
Stephanie Vaughn, Region 2
Kevin Bilash, Region 3
Fred MacMillan, Region 3
Donna McCartney, Region 3
Joseph McDowell, Region 3
Andy Palestini, Region 3
Jon Bornholm, Region 4
Leo Romanowski, Region 4
Julie Santiago, Region 4
Nate Nemani, Region 5
Bernie Schorle, Region 5
Gary Miller, Region 6
Raji Josiam, Region 6
Don Bahnke, Region 7
Mike Davis, Region 7
Harry Ball, Region 9
Ray Saracino, Region 9
Kira Lynch, Region 10
Kelly Madalinski, TIFSD
Dave Reisman, NRMRL, Cincinnati
Suzanne Davis, CA DTSC
Jim Harrington, NYSDEC
Peter Grant, Land Science Technologies
Keith Arnold, EMS, Inc.
In an effort to foster scientific and technical advances in characterization, monitoring and remediation of contaminated sites, the EPA Technical Support Project encourages full and frank discussion of all technical matters and related issues that come before it. Information presented in these minutes represent the views of the participants and has not received formal EPA peer review. Therefore, this information does not necessarily reflect the views of EPA or other participating organizations, and no official endorsement should be inferred. The information is not intended, nor can it be relied upon, to create any rights enforceable by any party in litigation with the United States or any other party. Use or mention of trade names does not constitute an endorsement or recommendation for use. Errors and omissions in the information will be corrected as they are found and time permits.
In an effort to foster scientific and technical advances in characterization, monitoring and remediation of contaminated sites, the EPA Technical Support Project encourages full and frank discussion of all technical matters and related issues that come before it.Information presented in these minutes represents the views of the participants and has not received formal EPA peer review. Therefore, this information does not necessarily reflect the views of EPA or other participating organizations, and no official endorsement should be inferred. The information is not intended, nor can it be relied upon, to create any rights enforceable by any party in litigation with the United States or any other party. Use or mention of trade names does not constitute an endorsement or recommendation for use. Errors and omissions in the information will be corrected as they are found and time permits.