C3 Environmental Limited

What is Waterloo Barrier®?
Waterloo Barrier® is a low permeability cut-off wall for groundwater containment and control. It is a new design of steel sheet piling featuring joints that can be sealed after the sheets have been driven into the ground. The product was developed by researchers at the University of Waterloo (UW) and has patent/patent pending status in several countries. CMRM assisted in the development of the product and are currently the sole manufacturer. Field tests confirm that Waterloo Barrier® is an effective method for providing low bulk hydraulic conductivity containment of ground water in subsurface soil environments.

Waterloo Barrier® Profile

Development of Waterloo Barrier®
Low permeability containment walls are increasingly being applied in the control and remediation of groundwater pollution. Conventional technologies such as slurry walls and geomembranes do not necessarily provide cost-effective and efficient subsurface contaminated in all settings. Groundwater researchers at UW considered this in their construction of containment cells for field experiments involving contaminated groundwater. The concept of driving steel sheet piling and sealing joints between adjacent piles was thus introduced. After a series of successful experimental cells the potential utility of Waterloo Barrier® in real site conditions was confirmed with approximately one year of prototype field-testing. UW and CMRM then collaborated to develop sheet piling in which a sealable cavity was incorporated into the pile interlock in the manufacturing process. A roll-formed shape was produced, and made available for field trials in 1991. Extensive field scale tests were conducted by UW, and bulk hydraulic conductivity values of less that 10-8 cm/sec were achieved. Installations of a commercial nature are currently in service.

University of Waterloo Barrier® Research Test Cell

Commercial Applications
Potential uses of the Waterloo Barrier® include:

deep, enclosing barriers around hazardous waste sites or municipal landfills.
shallow, enclosing barriers to contain petroleum products or other light contaminants which float on the water table.
shallow or deep enclosures to control future groundwater contamination at new industrial or waste disposal sites.
temporary, enclosing barriers to facilitate various removal or in situ remediation procedures.
barriers along shorelines to prevent seepage of contaminated groundwater into waterways.
isolation of accidental spills.
cofferdams in waterways to facilitate efficient dewatering procedures.
funneling or directing contaminated plumes to enhance the efficiency of pump-and-treat techniques.
groundwater control in construction projects involving excavating and tunneling.

Features & Benefits
rapid installation and sealing
minimal disturbance of site during construction.
Easily adapted to irregular layouts.
Limited site access less of a problem compared to alternative cut-off wall techniques.
Easily installed in areas with high water tables and surface water.
Easy to inspect and monitor for superior quality assurance and control during construction.
Predictable hydraulic performance.
Positive public perception.
Long service life for permanent installations.
Can be easily removed where applications are temporary.


Typical Sheet Pile Installation Set-up

Installation and Sealing
Waterloo Barrier® sheet piles are installed using the same equipment and techniques as conventional product. Vibro equipment is suitable for most soil conditions although better results may be achieved with impact equipment in certain cohesive soils. Vibratory drivers with an eccentric moment in the area of 3000 in-lbs are recommended for both WZ75 and WEZ95. Pile lengths of up to 70 feet are available and for greater depths the piles can be spliced. Corners and special fabrications are available for any geometric layout. A footplate at the toe of each larger interlock prevents most of the soil from entering the sealable cavity during driving. After driving the cavities are water jetted to remove small amounts of loose soil and are ready for the injection of sealant. A number of clay-based, cementitious, polymer and mechanical sealants are available to meet a variety of site conditions.

Typical Sealant Installation

Quality Assurance & Control
Potential leak paths through the Barrier are limited to the sealed joints and therefore the joints are the focus of the quality control procedures. Joints are inspected before the sealing operation to confirm that the complete length of the cavity is open and can be sealed. Video inspection equipment can be lowered into each clean cavity to provide a permanent visual record. Each joint is sealed from bottom to top facilitating the emplacement of sealant into the entire length of the joint. Repair procedures can be initiated if joint separation or blockage is suspected. Quality assurance and control is further confirmed by the requirement that the pile driving and sealing be carried out by or under the supervision of trained and licensed personnel.

Video Inspecting Equipment

Waterloo Barrier® is Available in Two Designs.

Specifications:
Raw Material: ASTM A572 GR50
Manufacturing: ASTM A6
Coatings: 1) Galvanized, ASTM A123, CSA G164
2)Coal Tar Epoxy, SSPC-16
3)Fusion Bonded Resin, ASTM A950.
Accessories Bends Can Be Supplied to any Angle.
'T' Sections and Other Welded
Fabrications are Available

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C3 Environmental Limited
is a member of
The C3 Group of Companies Telephone: (519) 648-3611
Fax: (519) 648-3505
Email: c3enviro@c3group.com
Web: www.c3group.com/c3environmental