What makes landfill sanitary

Landfills are required to budget for monitoring and maintenance for decades after closure to ensure that no harmful chemicals escape. Landfills are divided into sections, called cells, that are filled and closed sequentially. Cells can be anywhere from 2, square feet up to 20 acres or more, depending on the size of the landfill. Nowadays, the tendency is toward larger cells and landfills. When a new cell is built, the hole is lined with 2 feet of compacted clay, a durable plastic liner, and a nonporous geotextile membrane.

That outliner lining is covered with a layer of granular material that helps funnel liquids into a leachate collection system. Up to two feet of soil is layered on top of that before garbage is added.

Often, the first layer of garbage will comprise special materials such as old mattresses, to further protect the lining. Once the cell is constructed, municipal solid waste is dumped inside and run over by compacting tractors. At the end of each day, the garbage must be completely covered to minimize odors, deter pests, limit rainwater runoff, prevent waste fires, and discourage scavenging. Daily cover most often consists of six inches of soil. This can fill up a cell more quickly, so alternate daily covers, such as geotextile cloth or even certain types of waste like ash or tires, are sometimes used to maximize efficiency.

Wells and trenches for collecting landfill gas are installed at regular intervals as the landfill fills. This diagram from Advanced Disposal illustrates the elements of a modern sanitary landfill:.

When the cell is completely full, it receives a final cover, or cap, much like the bottom liner. The cap will be further covered by topsoil, which will be seeded with vegetation for the duration of the decades-long post-closure monitoring period. By far the largest environmental impact of landfilling is the production of landfill gas LFG.

Although landfills are designed to minimize decomposition, organic materials do eventually break down in a landfill. Instead of pouring chemicals down drain pipes or into the garbage can to contaminate our environment, modern landfills ensure safe disposal. These technological and ecological advancements help to maintain a safer, more environmentally friendly waste system. It was not until the turn of the 20th century, when urban areas began to fill up with more people and trash , that cities started doing something about their garbage.

In the s, it was common for garbage, incinerator ash and dirt to be used to fill in swamps near cities which allowed the contamination of groundwater. While we can never eliminate all contamination risks, modern landfills work to keep our cities clean and healthy as we continue researching new ways to deal with waste.

Take a look at the Sustainability section of our blog to learn how you can reduce the amount of waste you send to the landfill. Have thoughts on this topic? Head over to Twitter or Facebook and use dumpstersblog to join the conversation. You might think there's no safe way to get rid of hazardous items, but toxic waste landfills are actually carefully designed for safe disposal. Find out where hazardous waste goes and how it's regulated.

Prepping for a move? Making room for a new living room set? Use these tips for safely moving heavy furniture out of your house and into your dumpster.

Need a Dumpster? However, such an expensive high level of isolation may not be technically necessary to protect public health. Four basic conditions should be met before a site can be regarded as a sanitary landfill see following. The ways of doing this should be adapted to local conditions. The immediate goal is to meet, to the best extent possible, the four stated basic sanitary landfill conditions, with a longer term goal to meet them eventually in full.

A good lining can be made by compacting layers of clay, gravel, and soil. Building the landfill in an area with hard clay soil will make this easier. If there are resources to provide a better protective lining, layers of thick plastic sheeting and thick fabric will give more protection, and a system of pipes and pumps can be built to remove liquids. The way you fill a landfill depends on the amount of trash, how much time people have to do the work, and the local climate.

In places with high rainfall and little trash, such as towns that practice zero waste , each week or month you can dig a new hole lined with clay and gravel in thinner layers than a larger landfill would need. Someone takes responsibility for bringing trash, filling the hole, compacting the trash, and covering it with soil. Burying trash little by little prevents water from collecting in the pits.

For a community with a large trash load, it is easiest to dig a large pit. Landfill workers add waste to the pit as it is brought in. Each time waste is added it is pressed down to make an even layer, then covered with large leaves such as palm, banana, or palmetto and a layer of soil, or soil, ash, and sand. This will prevent bad smells and stop insects from breeding. Making a large roof over the pit will keep rain out. When the pit is full it should be capped with a layer of soil at least 90 cm deep.

Wildflowers or grasses can be planted over it, but not plants that will be eaten, such as vegetables or fruit trees. Until the landfill is completely covered by plant life, it is best to keep grazing animals away. A pit where trash is dumped and then covered with soil can be maintained safely with few problems.

But it can develop problems if liquid waste and gas methane collect in the pit.