Sealing systems in landfill construction: installation by a certified specialist

What are landfill base sealing systems?

The base sealing forms the first protective barrier of a landfill. It consists of multiple layers — typically a mineral liner and an overlying geomembrane — to prevent leachate from seeping into the soil and groundwater. Base sealing is regulated by the German Landfill Ordinance (DepV), which sets the requirements for each landfill class (DK 0 to DK III).

Why is sealing crucial?

An effective base sealing system protects the environment from landfill leachate. Leaks can lead to significant soil and groundwater contamination with ecological and health consequences. Proper sealing ensures that potentially hazardous substances are securely contained.

What is landfill intermediate sealing?

Intermediate sealing systems separate different areas or phases of a landfill. They are used when sections are temporarily out of operation, when the approved waste height has not yet been reached, or when settlement is still expected in former municipal waste landfills — and in the ‘landfill on landfill’ concept. Intermediate sealing minimises rainwater infiltration and supports gas management.

Why is sealing crucial?

An effective intermediate sealing prevents leachate from infiltrating the underlying waste layers and protects the environment from harmful substances. It also supports the long-term stability and safety of the landfill.

What is landfill surface sealing?

Surface (capping) sealing systems are installed on top of the completed landfill body to prevent rainwater infiltration and minimise the release of pollutants and landfill gases. They typically consist of several layers — a sealing layer, a drainage layer and a recultivation layer — working together to reduce environmental impact.

Why is sealing crucial?

Capping prevents rainwater from infiltrating the waste body and forming leachate, and it reduces the emission of landfill gases, which can be hazardous to health and the environment. Without proper capping, these pollutants can escape and cause significant damage.