Do you want to hear something surprising? Every single day, Americans produce 4.9 pounds (2.2 kilograms) of trash per person. That’s a lot, right? Well, it all adds up to a whopping 292.4 million tons (265.3 million metric tons) of garbage yearly! In fact, that’s three times more than the average amount of trash produced globally.
So, have you ever wondered what happens to all this trash you throw away? You know, like the cups, utensils, and leftover food from a restaurant meal? Or have you ever thought about where the garbage truck that just left your neighbourhood is headed?
Well, some of the trash is recycled or recovered, and some of it is burned. But the majority of it ends up in landfills. This article is here to give you the lowdown on how landfills work, the different types of landfills, and their pros and cons. So, let’s dive in and learn more!
What is a Landfill?
First of all, let’s understand the concept of landfill! Modern landfills are specialized dumping grounds for solid waste that are designed and managed to comply with federal regulations and protect the environment from harmful contaminants.
These facilities are strategically located in areas that are not environmentally sensitive and are equipped with on-site monitoring systems to check for any signs of groundwater contamination and landfill gas.
To meet the strict requirements of the Resource Conservation and Recovery Act (RCRA), landfills must adhere to stringent design, operation, and closure standards. It is important to note that disposing of waste in landfills is just one aspect of a comprehensive waste management system.
The EPA advises communities to prioritize source reduction while keeping the waste management hierarchy in mind when designing waste management systems. It is essential to minimize waste volume and toxicity as much as possible.
What are Different Types of Landfill?
Landfills are either regulated under Toxic Substances Control Act (TSCA) or RCRA Subtitle D (solid waste) and Subtitle C (hazardous waste). Following are the details:-
Regulated by the Toxic Substances Control Act
- Polychlorinated Biphenyl (PCB) landfills – Some PCBs decontamination processes do not require EPA approval, but most of them do.
Regulated by Subtitle D
- Bioreactor Landfills – A type of MSWLF that rapidly transforms and degrades organic waste.
- Municipal Solid Waste Landfills (MSWLFs) – Particularly used for household waste and non-hazardous wastes.
- Industrial Waste Landfill – These are specifically designed to collect industrial waste. They have the following two sub-types.
Regulated According to Subtitle C
- Hazardous Waste Landfills – As the name suggests, these are only used for the disposal of hazardous waste.
How Do Landfills Work?
Modern landfills are constructed with a special layering system that helps keep the waste isolated and protects the environment from harmful by-products or leaks. It’s essential to keep the trash separated from the air and water to avoid any contamination.
By examining each layer of the landfill, you can get a better understanding of how they work. So here they are:-
Layer 1: Cells (Old and New)
The first layer of a landfill is the cells, which are essentially giant holes in the earth where waste is deposited. Old cells are filled with waste and capped off, while new cells are excavated and lined with specialized materials to prevent contamination. These cells are carefully designed to minimize the impact on the surrounding environment.
Layer 2: The Liner System
The liner system is designed to prevent waste from seeping into the surrounding soil and groundwater. This layer is made up of multiple components, including a thick layer of clay, a synthetic liner made of plastic, and a layer of gravel. The liner system is essential for keeping the environment safe from toxins and pollutants.
Layer 3: The Drainage System
The drainage system collects any liquid that seeps through the liner system. This liquid, known as leachate, can be incredibly toxic and damaging to the environment. The drainage system ensures that any leachate is collected and treated before it can cause harm.
Layer 4: Groundwater Monitoring Stations
These stations are strategically placed around the landfill to monitor the groundwater for any signs of contamination. If any contamination is detected, steps can be taken to prevent it from spreading.
Layer 5: Gas Collection System
The purpose of the gas collection system is to collect any methane gas produced by the waste. Methane gas is highly flammable and dangerous, so it’s important to collect it and prevent it from building up. This system also helps to reduce greenhouse gas emissions.
Layer 6: Cap
The final layer is the cap, which is essentially a giant cover for the landfill. The cap is made up of multiple layers of materials, including clay, plastic, topsoil, and plantation. The cap helps to prevent any rainwater from seeping into the landfill and also helps to control odors.
What are the Benefits of Landfills?
Landfills are not just a place where trash goes to sit and rot, but they have several Benefits. Let’s dive into 6 advantages of landfills:-
Gone are the days of open-air landfills that caused pollution and attracted vermin. Modern landfills are designed to be much more eco-friendly. They are lined with impermeable materials to prevent contamination of soil and groundwater. They also have systems in place to capture and treat wastewater.
Landfills are actually a cheaper option for waste disposal than other methods, such as incineration. This is because the cost of building and maintaining a landfill is relatively low compared to other methods. Plus, the revenue generated from capturing and selling methane gas can help offset these costs even further.
Clean Cities & Towns
Landfills help keep our cities, towns, and districts clean by providing a place for waste. Without them, we would be left with piles of trash on the streets, which would attract vermin and cause all sorts of health and safety issues.
As organic waste decomposes in a landfill, it produces methane gas. This gas can be captured and used to generate electricity. In fact, many modern landfills now have systems in place to capture and use this gas to power homes and businesses in the surrounding area.
Creation of Jobs and Businesses
Finally, landfills can actually support jobs and local businesses. From the construction and maintenance of the landfill itself to the jobs created by recycling programs and energy generation, landfills can provide a boost to the local economy.
Segregation of Hazardous Waste
Not all waste is created equal. Hazardous waste, such as chemicals and medical waste, must be kept separate from regular trash. Landfills provide a safe and secure place for this type of waste to be disposed of properly, ensuring that it doesn’t contaminate the surrounding environment.
What are the Disadvantages of Landfill?
With so many pros of landfills, there are certain downsides as well. It’s essential to understand both the pros and cons of landfills. So, the following are the 6 major disadvantages of landfills:-
Somewhere Responsible For Climate Change
The first and foremost disadvantage of landfills is that they are, in a way contributing to climate change. When organic waste decomposes in a landfill, it produces methane gas. Methane is a potent greenhouse gas that contributes significantly to global warming.
The Danger of Methane Gas
Methane gas is not only a contributor to climate change but also flammable and explosive. If it accumulates in the landfill, it can explode, causing a fire. This can lead to significant damage to the environment and human life.
Contamination of Water and Soil
Not always, but sometimes, the toxic chemicals and heavy metals present in the waste can seep into the groundwater and soil, contaminating them. This can have severe consequences for the environment and human health.
Effects on Wildlife
Landfills can also have harmful effects on wildlife. The toxic waste can attract animals, which can lead to their deaths. The accumulation of waste can also destroy the natural habitats of animals, leading to a decline in their population.
Possibility of Accident
Landfills are not always safe. There is always the possibility of an accident. For example, a trash compactor can malfunction, leading to the release of toxic waste. This can harm the environment and the people living in the surrounding area.
Effects on Human Health
The toxic waste can lead to respiratory problems, skin irritation, and other health issues. Landfills can also attract pests like rodents and insects, which can spread disease.
How is Waste Treated in a Landfill?
Video by WM
There is very little oxygen and moisture in the landfill. Thus, it takes a really long time for the trash to break down. So, the main purpose of landfills is to bury the waste materials, not to break them down. Once a landfill is full, it is usually capped off. However, the capping systems differ for general trash and hazardous waste materials.
For hazardous waste, a synthetic material is used to cover the waste, followed by two feet of compacted clay. A drainage layer is also used to get rid of any liquids and chemicals as the waste breaks down. Finally, a layer of dirt or topsoil is added to complete the capping system.
A solid liner system is positioned at the bottom of the landfill for general waste. Then, layers of compacted clay and synthetic material are alternately placed over the waste site. After that is finished, the clay is covered with a final coat of dirt.
How are Modern Landfills More Sustainable?
There’s been a lot of recent changes in how landfills work. It has improved from the filthy trash heaps of the past to enhancing sustainability and reducing environmental impact. Here are some examples of how they are achieving this goal.
Waste to Energy
Some of the landfills are actively converting the gas produced at their sites into electricity. This concept of waste to energy significantly helps reduce our dependence on non-renewable energy sources such as oil.
Landfill gas is converted and used as fuel to generate electricity at power plants operating in industries. The gas is filtered to natural gas quality and used in places where natural gas is typically used, such as kitchen stoves.
Separate Drop-off Sites
Separate landfills for different kinds of waste increase the ecological benefits of landfills. This is especially important for hazardous materials. But don’t forget about organic waste, like food and greens. They release a lot of unpleasant gasses and odors into the air. Luckily, some landfills have special green drop-off areas for organic waste.
It’s becoming increasingly important to focus on the waste around us. Nowadays, landfills have come a long way from just being basic holes in the ground to advanced waste management systems carefully designed to minimize pollution, control contamination, and safeguard our well-being and surroundings. Although there may always be some risk of contamination, landfills play a crucial role in maintaining clean and healthy cities.
What is a sanitary landfill?
Modern engineering landfills allow garbage to break down into chemically and biologically inert elements in a setting that is disconnected from the environment. These landfills are known as sanitary landfills.
What Happens to Trash in Landfills?
Over time, organic matter decomposes, producing gases like methane. Landfills collect and control these gases, but decomposition is slow, taking years or decades. Efforts are made to reduce waste sent to landfills through recycling and waste reduction initiatives.
What is the difference between a landfill and a dump?
A landfill is a location subject to government regulation where garbage is appropriately stacked, monitored, and handled. A dump is typically an unlicensed, unlawful location where individuals dispose of their rubbish, endangering the environment.
What are Subtitle C and Subtitle D landfills?
Landfills are divided into two subgroups by the EPA: Subtitle C and Subtitle D. A hazardous waste landfill is a Subtitle C landfill. Gersdorf asserts that Subtitle C landfills will not accept any solid trash. Industrial and MSW landfills are under Subtitle D.
Are Landfills Bad for the Environment?
While modern landfills are designed to contain toxic waste, leaks do occur. Therefore, landfills continue to be hazardous to the environment and human health. Methane released by the decomposition of waste is a powerful greenhouse gas that contributes to global climate change.
Compactor Management Company (former Northern California Compactors, Inc.) offers installation and support services for waste recycling equipment such as waste compactors, balers, shredders & conveyor systems. Established in 1981, it offers waste management solutions across the United States.