What are the basic characteristics of a modern landfill site? List any three and also mention the reasons for their use.

(N/A) The basic characteristics of a modern landfill site include:
$1$. Lining with clay or plastic liners: These are used to contain leachate,preventing it from contaminating groundwater.
$2$. Compaction and covering of waste: Waste is compacted and covered daily with soil or other materials to prevent it from being blown by wind,reduce odors,and discourage pests.
$3$. Landfill gas extraction system: These systems are installed to collect gases like methane,which are then used for power generation or heating,reducing greenhouse gas emissions.