Layers of a Landfill: Guide to How Landfills Are Constructed

What is a Landfill?

A landfill is a land site that is dedicated to the disposal of waste materials by burial and which may be covered or landscaped. Excavated landfills may be used temporarily for solid wastes, while land reclamation affords an opportunity to reclaim land for other purposes. Landfills pose issues such as pollution and contamination. They are also known as dump sites.

How Are Landfills Constructed?

The design of landfills varies depending on the amount of waste it will contain; however, there are several basic layers that can help guide their construction. The first layer is often called a “leachate collection layer.” This water-resistant barrier is made of an impervious plastic sheeting or geomembrane. It collects liquids that percolate through the waste, preventing them from seeping below the landfill to contaminate ground and surface waters. The second layer is a compacted clay liner, which is placed either to prevent landfills from floating in water caused by leachate or to keep landfills from seeping into the ground. The third layer of landfills includes a topsoil covering that helps landscape and vegetation growth. Lastly, landfills sometimes have a cover consisting of an airtight membrane over the landfill’s contents to reduce odor causing bacterial action and oxygen demands on organic material in addition to reducing rainwater infiltration and windblown refuse.

How Are Landfill Roads Made?

Fortunately landfills receive so much traffic that construction firms have created machinery called landfill compactors to improve the road quality for trucks involved in landfill transportation. These machines do things like crush old car parts so they cannot puncture tires while driving, level out bumps in the roads, and smooth out loose dirt that may cause pullover accidents for drivers who are unaccustomed to riding through landfills. Midwest Companies provide road base materials such as shredded railroad ties and post-consumer wood waste to local landfills. They can be used to improve landfills reducing the need for compaction to provide a smooth surface.

In the end, landfills pose a few environmental issues, but they are necessary for our society to function properly. Without landfills, land would be used inefficiently and there would not be any limits to where landfills could be placed. It is important for landfills to have the right layers in place, however, as this helps with their functionality and effectiveness.