A sealed sheet piled wall provides a safe and economic solution where the control of groundwater could be a problem.  It is also effective as a containment barrier to prevent leachate ingress or leakage at a site perimeter.

Sealant systems are designed to stop water penetrating through the pile clutches and primarily work in three ways.  They either form a seal between two particular points on adjacent piles or replace the fill in the void between the piles.

The simplest form of sealant is a hot applied bituminous material or a compressible sealant.  These are easily applied but offer the least amount of reduction in permeability.  Hydrophilic sealants offer a further reduction in permeability but have to be applied with care, and protection will be required from the time of application to the completion of the pile installation.  Welding of the clutches of the piles will produce a joint with no permeability, but as would be expected, this is the most costly option.

The choice of sealant will also be affected if high pH, salt or saline water or contaminants are anticipated to be encountered.