The diagram shows how a contemporary landfill for household waste is designed and operated.
Overall, the landfill system consists of three distinct stages – construction, use, and closure – and is carefully engineered to minimize environmental damage by controlling both liquid and gaseous waste.
In the initial construction stage, a large man-made pit is excavated in an area of natural rock. The base and sides of this cavity are then sealed with a layer of clay followed by a synthetic lining, creating an impermeable barrier that prevents contamination of the surrounding ground. At the bottom of the landfill, a series of drainage pipes is installed, allowing waste liquid to be collected and transferred to a drainage tank.
During the operational phase, household waste is delivered by trucks and deposited into the lined pit. As the waste builds up, liquid waste, known as leachate, is produced and gradually drains downwards through the pipes into the collection tank.
In the final closure stage, once the landfill is full, it is sealed with a thick clay cover. Ventilation pipes are added to release gases generated by decomposing waste, ensuring pressure does not build up underground. This final sealing process allows the landfill to remain stable and environmentally safe over the long term.