The pictures depict how a modern landfill for household waste is designed.
Initially, a large man-made hole was dug into the ground, which is located above natural rocks. Next, the hole is covered with several layers of synthetic substance and clays to prevent leakage. In addition, a system of drainage pipes and a drainage tank are installed at the bottom to collect liquid waste.
Secondly, solid household waste is poured into this hole. When the hole is full, it is covered with a thick layer of clay. Underground, the solid waste begins decomposing. At the same time, when the waste stays there, it produces liquid which filters down to the bottom.
Finally, this decomposition process produces gases and harmful toxic liquid. The gases are collected through pipes at the top while the toxic waste liquid filters down to the bottom and is drained through pipes and pumped out to be treated.
Overall, the diagram shows how a modern landfill is constructed and how waste is processed underground.