Environmental specialists have engineered a continuous trench method of landfilling that is used at the Lambton Facility. This method complements the site's natural ability to isolate waste from the surrounding environment. The secure landfill cells are dug 18 metres (60 feet) deep, and are continuously filled and capped. The continuous trench method ensures that waste is placed in the secure landfill and sealed over with a clay cap as quickly as possible, a system that protects employees, the surrounding community and the environment.
The cap consists of about six metres (18 feet) of dense clay, which was excavated to create the cell. The top layer of recompacted clay prevents rainfall from entering the cell. Natural runoff water present in the cell before it is capped is pumped out and treated in the facility's incinerator.
Once a part of the cell has been sealed, it is covered with topsoil and the area is seeded with grass.