How do Landfill Sites Work?
‘Out of sight, out of mind’ is a truism, that’s for certain, but what about if we bring a little more mindfulness to things we discard? While many of us are keen to donate our old goods to charity and recycle where possible, the average person in the United Kingdom disposes of approximately 400 kilograms of waste every year. As a nation, we recycle 12 million metric tonnes of waste although not everything can be recycled and untold numbers of recyclable items may be discarded as general waste.
Waste that cannot be recycled or repurposed is simply sent to landfill. In Britain, that figure reaches a hefty 14 million metric tonnes per year. Landfill sites provide a seemingly convenient solution to a waste management problem, with the massive costs of that convenience externalised to both the taxpayer and the wider environment.
Landfills are essentially active waste treatment zones, producing huge volumes of methane, CO2 and leachate. Leachate refers to the contaminated liquid formed by water percolating through a solid waste disposal site, accumulating toxins and flowing into subterranean areas. These toxic areas are unsightly eyesores of rubbish and a significant source of pollution.
According to Data.Gov, as of late 2021 there are around 500 licensed operational landfills in the UK, with rubbish buried and slowly degrading, posing a risk for future generations. Landfills have a tremendously toxic impact on the environment. Greenhouse gases are released into the atmosphere, with methane – a potent greenhouse gas 25 times stronger than carbon dioxide – produced as a result of peoples’ unwanted waste.
But what actually happens to waste at the landfill site, from development to disposal?
First, the site is prepared. The ground foundation is sealed with multiple layers of linings to limit the number of toxic chemicals leaching into the surrounding earth. This is then verified independently for quality assurance. During preparation, the surface is smoothed out by fitting a regulating layer, which is then covered with a layer of clay which offers an impermeable material to help prevent liquid from escaping. A third plastic-lining layer is then laid, which is covered with Geotextile. A fifth gravel layer is then applied and prepared with a final layer of geotextile.
Waste tipping and cell compacting
When the site is ready to receive waste, all general waste from the surrounding geographical region is collected and transported to the facility where it is deposited in specifically designated cells. A compactor then crushes the waste, rolling it out over the area, resulting in a level surface of compacted waste built up in each waste cell. At each stage, these layers are then covered with special matting or soils to help contain odours and secure the waste in place.
Extraction wells within each cell allow for the capture and processing of gases. Instead of escaping into the air, landfill gas can be captured, converted, and used as a renewable energy resource. Utilising otherwise harmful emissions prevents methane from polluting the atmosphere and provides renewable fuel for vehicles, industry and wider society.
Leachate is the contaminated liquid that forms when water seeps through a solid waste disposal site, picks up toxins and flows into underground areas. Leachate is collected, treated and taken to be disposed of.
Land Capping & Restoration
Once each designed cell has reached a certain level, the land area is then capped with a cover ahead of land restoration. The purpose of restoration is to restore the land to the point of encouraging nature and wildlife back, which involves creating several layers of high-tech geo lining, subsoils and topsoil to seal what is beneath.
Why are they necessary?
When it comes to dealing with the remnants of waste generated by businesses and households, landfills serve as a key infrastructure gap. As the world’s population grows and consumer habits continue to evolve, it is projected that this waste will increase.
After a number of decades, the landfill will continue to emit unwelcome and hazardous gases, necessitating the need for the area to be monitored indefinitely to guarantee that there is no excessive pollution or critical issues.
Despite the promising increase in recycling rates, there is still a need for safe and effective waste management systems. Until manufacturing and consumer habits can change, landfill sites are a necessary solution for the waste we cannot yet recycle.
The waste disposed of at landfill sites includes both residential and commercial waste, creating a mounting problem and contributing significantly to global warming. If concentrations of methane continue to rise, our atmosphere will become increasingly toxic, devastating all life on earth. The vast majority of us agree that we should do everything we can to reduce the amount of waste we send to landfills, if not eliminate it altogether.
With increased awareness and eco-options becoming more accessible, many of us strive towards a zero-waste lifestyle. A zero-waste lifestyle entails avoiding single-use plastic whenever possible and instead relying on sustainable and reusable alternatives. In other words, you’re aiming to send as little waste as possible to landfill. If unsure where to start, remember the three Rs: Reduce, Reuse, Recycle. This mantra helps to mindfully and purposefully make more eco-friendly choices when discarding unwanted goods.
With increasing options for environmentally-friendly, biodegradable food and drink packaging, to sustainable and plastic-free fashion, the circular economy benefits the environment and public spending, placing less strain on the taxpayer and less pressure on the planet.