The diagram illustrates the design and operation of a modern landfill site for household waste, detailing four key stages: construction, usage, and eventual closure.
In the construction phase, a man-made cavity is excavated into a natural rock base. This hole is then lined with a thick layer of clay followed by a synthetic substance, both acting as protective barriers to prevent contamination. A drainage system, consisting of several pipes and a drainage tank, is installed at the bottom to collect and channel liquid waste.
The usage stage involves the deposition of household waste into the prepared site. As waste accumulates, liquid by-products (leachate) are generated and removed via the installed drainage system, ensuring that toxic substances do not seep into the surrounding environment.
Once the landfill reaches capacity, it enters the closure phase. The site is covered with a final layer of clay to isolate the waste. Additionally, vertical pipes are embedded to extract gases produced by the decomposition of organic materials, preventing their uncontrolled release into the atmosphere.
Overall, the modern landfill is a carefully engineered system that not only stores waste securely but also incorporates mechanisms to manage hazardous by-products, thereby minimizing its environmental impact.