When most people envision a landfill, the images that most likely come to mind are those of great heaps and mountains of garbage with a steady stream of dump trucks running day and night and piling more and more on top of what is already existing. While, part of this image may be accurate, the modern landfill is quite different. With people becoming more aware on a daily basis of the impact their actions have on the earth, even landfills are being designed with conservation and sustainability in mind.
The Environmental Protection Agency summarizes modern landfills as "well-engineered facilities that are located, designed, operated, and monitored to ensure compliance with federal regulations." In order to ensure that these regulations are being followed in modern landfills there are various protocols in place.
One of the first things considered in the planning of a landfill is location. They must be built in a suitable geographic location, away from wetlands, faults, or any restricted areas. Once a location is chosen some sort of liner must be laid in place to prevent any contamination of groundwater and underlying soil. One of the more popular liners currently being used is a geosynthetic liner. These liners are made up of a very thin layer of clay sandwiched between two layers of some sort of geotextile. These are durable and more efficient to install than the more traditional clay liners. A geosynthetic liner is also highly popular in areas with significantly varying temperatures. They stand up well to freeze and thaw cycles. Many modern landfills also consist of some sort of leachate collection and removal system. This is installed on top of the liner and acts to remove sludge and other harmful leachate from the landfill for treatment and removal.
Modern landfills have a much smaller impact on the environment than landfills of the past. Once in place, operating practices are strictly monitored. Periodically, the waste is covered with a layer of compact soil. This helps to protect public health by minimizing odor, insects, and rodents. There are also scheduled ground water checks to ensure that nothing harmful from the landfill has leached into the groundwater. When it does come time for the landfill to close, there are strict protocols in place to continue to protect the environment and help to provide long term care for the closed landfill areas, making our earth a better and cleaner place for all.