A landfill site (also known as a tip, dump, rubbish dump or dumping ground and historically as a midden) is a site for the disposal of waste materials by burial and is the oldest form of waste treatment. Historically, landfills have been the most common method of organized waste disposal and remain so in many places around the world.

Sanitary landfills are a method of waste disposal where the waste is buried either underground or in large piles. This method of waste disposal is controlled and monitored very closely.

For sanitary landfills, the process starts by digging a large hole in the ground that is then lined with thick plastic (normally 2-4 feet thick) and a layer of impervious clay. The bottom of the landfill is also lined with a network of plumbing that functions as a collection system for any liquids. Leachates is the term used to describe liquids that leach or leak from the landfill, and this system collects the leachates. These components of the sanitary landfill help prevent materials and liquids from spreading to the surrounding ground and waterways.

Once the landfill is set up, waste can then be added to the landfill. Instead of simply filling the landfill completely with waste, the landfill is organized in layers. The layers alternate between waste and soil. This alternation of materials reduces odors and allows for more rapid decomposition, which is the breakdown of materials. When a landfill is full, it is sealed and covered in a thick layer of clay. Once the landfill has been evaluated and considered safe, it can be converted into a park or open space for human use. It is interesting to think that a location where we put our unwanted materials can then be turned into a location for recreation and fun.In this way solid waste is managed by landfills.