Waste management is a sector that keeps evolving. Since companies have been producing increasingly complex products, our waste disposal systems have had to adapt. Unfortunately, the rising complexity of our products is seriously outpacing the advances that our waste disposal systems are making.
Effective trash disposal is extremely important for avoiding pollution. Whether our trash ends up polluting oceans, land, or the air we breathe – it inevitably threatens our environment and contributes to biodiversity loss and climate change. The key in this section is to remember that throwing something out does not make it disappear.
Municipal Solid Waste
Municipal solid waste [MSW] is a large category of public waste that includes ‘regular’ garbage, compost, and recyclables.
2.01 billion tonnes [20.1 billion pandas] of MSW were generated in 2016 alone. This yearly waste output is projected to increase by 69% by 2050. Unsurprisingly, developed countries generate the most waste per capita, with North America leading the way with 2.21 kg of waste per person per day [globally, the average is 0.74 kg/capita each day]. This helps explain how 3 North American countries alone [Bermuda is included] are responsible for around 14% of the world’s MSW output – although they represent less than 5% of the global population.
In 2016, these 2.01 billion tonnes of MSW emitted 1.6 billion tonnes of CO2e. That’s around 3–5% of global GHG emissions the same year – and it’s not getting better. A 63% increase in MSW emissions is projected by 2050, should no improvements be made to the waste management process.
Types of MSW
As we’ve mentioned previously, MSW is a broad category that encompasses many different types of waste. Globally, MSW is dominated by organic waste. This isn’t very surprising considering that roughly a third of all food produced for human consumption is wasted or lost.
Since MSW holds so many different types of trash, improving waste management as a whole is complicated. That’s why the US Environmental Protection Agency developed a waste management hierarchy that outlines the best general approach to reduce waste and its impacts. The hierarchy is essentially based on the 3 Rs. When none of these Rs can be applied, waste ends up in landfills – hopefully.
Regular Garbage: Landfills and Waste-to-Energy
Regular garbage is the unsorted type of garbage. It includes everything that isn’t recyclable or compostable. In developed countries, regular garbage usually ends up in landfills or is incinerated – although a few exceptions exist [e.g. hazardous waste]. In landfills, trash is piled up and compacted, filling huge craters with garbage. In waste-to-energy plants, trash is burned to recover energy, producing waste ash, CO2, and other pollutants in the process. In essence, waste-to-energy helps smaller countries avoid relying on large landfills but create other types of waste that also need to be dealt with. For this reason, waste-to-energy is not really a waste disposal method – it is more of an intermediate step that can help reduce waste volumes.
A good waste management system is one that tries to divert the most waste away from these landfills or waste-to-energy plants, to increase their lifetime and recover anything that still has value [e.g. recyclable materials, compostable organic matter, etc…].
A well-designed landfill has many pollution control measures in place to avoid having pollutants seep into the soil or being emitted into the atmosphere. It especially aims to control methane emissions [since methane is 28 times more greenhousy than CO2] that are emitted by microbes as waste decomposes in anaerobic conditions. Capturing the gas and using it as an energy source is a great way to generate power while offsetting emissions that would otherwise come from the grid’s ‘normal’ natural gas. Otherwise, simply burning the methane without capturing the energy also helps lower GHG emissions, since CO2 will essentially replace methane.
Although landfills certainly have lower impacts than open dumping methods, it’s important to remember that emissions also arise from the construction and operation of the landfills – which require continuous compaction every day. GHG emissions can also come out of leaky pipes that transport methane. Additionally, landfills are above all giant craters filled with trash, and there’s nothing eco-friendly about that. Especially if ecosystems were cleared to make way for these landfills.
That being said, loads of trash that should end up in landfills don’t. And unfortunately, not all landfills are designed to protect their surroundings.
While even the best designed landfills don’t have net-positive impacts on the environment, they’re far better than other ‘regular’ garbage disposal methods.
Open dumping is a particularly undesirable alternative, as uncontrolled waste ends up causing loads of pollution and biodiversity loss. Trash literally invades ecosystems and mixes with the environment, where animals can fall prey to delicious-looking plastics. Additionally, some of the plastics can degrade into microplastics over time, which can easily be ingested by marine animals. And as long as we keep fishing plastic-eating seafood, we’ll keep ingesting plastics as well. For reference, an estimated 8 million tonnes of plastic are discharged in the ocean every year.
The following graph shows how our global waste management system deals with plastic.
Alas, plastics aren’t the only materials that have serious impacts when open dumped. Uncontrolled waste of all kinds pollute ecosystems and the atmosphere.
Recycling waste is essential as well, yet only 13.5% of global waste is recycled. On top of diverting waste away from landfills, recycling also leads to less pollution and less depletion of our natural resources, since we’re reusing materials that have already been extracted and/or manufactured.
The central pillars of a circular economy [a few examples] are that materials can be recycled efficiently enough to avoid waste, decrease resource extraction, and reduce energy consumption across all sectors. Although this closed-loop system can’t emancipate us fully from resource extraction or energy use, we’d have much to gain from getting as close as we can to a circular economy. Even the slightest improvements to our current recycling systems would make a big impact.
However, as we’ve seen in earlier sections [The 3 Rs], recycling has numerous challenges to overcome to improve its efficiency. Although there isn’t much we can do to design better recycling systems at the individual scale, we can all still chip in to make recycling plants more efficient.
Particularly, it’s important that individuals sort their recyclables according to their regional guidelines, since that would help recycling plants run a little smoother. In North America, it’s estimated that 25% of all items sent to the recycling plant aren’t even recyclable. Lowering this would increase the facility’s efficiency and improve the quality of the recovered materials. For reference, China – who imported and recycled around 2/3 of global recycled plastic waste in 2016 – implemented a 0.5% contamination limit for plastics and other types of recyclables in 2018. That’s 50 times below North America’s contamination rate of 25%.
Since developed countries struggle to remain below the contamination limit, many have decided to export their recyclables to other countries than China – or to simply bury their recyclables in landfills. Both these options are terrible.
Developed countries have the means to recycle their trash efficiently, but instead choose to pollute by exporting their waste to developing countries that simply don’t have the resources to recycle as well as we do. Effectively, developed countries are choosing to increase global pollution levels by turning a blind eye to their exported waste once it leaves their frontiers.
Composting and Food Recovery
Like recyclables, compostables can be diverted from landfills and treated separately. In essence, composting is all about using food waste efficiently, by taking advantage of the nutrients found in organic matter.
Fruit peels, veggie stems, and even paper towel are all good to go in the composting bin. Although food and greens make up around 44% of global waste [larger share in underdeveloped countries, since they have lower amounts of other types of trash], composting only represents 5.5% of global waste treatment.
A common question is: if compostables degrade quickly into natural products, why does composting even matter?
Well, there’s a few reasons. First, it helps reduce GHG emissions considerably. Organic matter degrades differently whether it’s in contact with air or not. In a landfill, food scraps aren’t in contact with air, so they release methane as they decompose. On the other hand, composting is done in the presence of air, which significantly reduces GHG emissions – since the decomposition just produces CO2 and water [CO2 being 28 times less greenhousy than methane]. Additionally, well-balanced composting processes can prevent a good chunk of those emissions, by locking up organic waste’s carbon into the compost product.
This brings us to the next point, which is that compost can be used as a carbon/nutrient-rich fertilizer. This means compost can replace synthetic fertilizers while improving soil quality where needed. Compost could particularly help soils that have had their nutrients sucked dry from unsustainable agriculture or that have been polluted. On top of remediating soils, composting is a cost-effective solution for improving a soil’s water retention, carbon storage, and fertility. We’ll talk about nutrient cycles in greater detail in a later section.
Unfortunately, only a fraction of all food wastage ends up being composted, while most of it finds its way into landfills or is open dumped. That’s too bad considering some studies estimate that a single household can help divert up to 150 kg of compostable material per year away from landfills.
With all this a few concepts become clear. If we want to reduce our impacts on the environment, we have to limit the amount of waste we generate. Simple ways to do that include producing higher quality products and reducing by design. For individuals, avoiding the purchase of single-use and unnecessary products is always a good way to reduce personal impacts. Then, to make sure that the waste we do generate has as little an impact as possible, sorting our trash according to regional guidelines will be necessary, especially for companies. As a little motivation, we need to remember that everything we throw out will end up polluting somewhere. It’s simply up to individuals, companies, and governments to make sure that this ‘somewhere’ is the appropriate disposal facility.
Better recycling systems will create more jobs all along the official recycling process, but also for informal recyclers like trash-pickers. As recycling improves and becomes profitable for even more materials, a greater number of individuals will be able to make a living off trash-picking. Not only will this help keep cities clean, it will also help many poor individuals make enough money to survive. This type of system helps explain why some countries that have poorer populations than developed countries actually recycle stuff better.
Apart from reducing the amount of waste generated, the most important thing we can do when managing waste is collecting it. Developing regions of the world are suffering from very low waste collection rates. This can emit significant amounts of GHGs and contribute to biodiversity loss, as uncollected waste is usually open dumped or incinerated [not in waste-to-energy plants].
And although some regions may have good collection rates, it doesn’t mean the waste is treated in the best ways possible.
Alas, there isn’t much information on the quality of the landfills between different regions of the world, so we can’t get a better comparison than this. However, we should note that replacing open dumping with any quality landfill is already a huge step in the right direction.
Open dumped waste has roughly the same effect as uncollected waste in the long run. The only difference is that organized open dumping allows waste management systems to ‘aim’ where the trash gets piled up – to avoid littering cities or freshwater bodies that populations depend on.
There’s a pattern in some middle-income regions where waste collection rates are good, but there isn’t enough effort being done to divert waste from landfills. That may seem cheaper, but diverting waste through recycling or composting can help extend landfill lifetimes, reducing costs significantly. And of course, the more waste properly diverted from landfills, the better for the environment.
With such gaps in waste management efficiencies between developed countries and other regions of the world, it becomes even more important to take advantage of good recycling systems. Developed countries need to stop exporting their trash to other countries that don’t have better waste management systems in place– it only leads to more pollution worldwide.
Sending our trash to other places of the world that have weaker recycling systems and/or fragile environmental regulations doesn’t mean we’ve successfully managed our waste. As long as developed countries keep voluntarily polluting foreign environments this way – instead of using their important scientific and economic resources to improve local waste management – national waste and emissions statistics won’t mean anything. And there’s no way developed countries can seriously claim to ‘strive for a greener future’ when their waste management strategies consist of exporting trash and forgetting about it.
There are examples of great waste management systems in the world, like the green dot program that originated in Germany roughly 30 years ago. It has since spread to most EU countries. Why not make it global to take advantage of the good ideas we come up with every few decades?
The graph above shows how incredibly wasteful the industrial and agricultural sectors are [among others]. These numbers are very concerning, especially when we compare them to the MSW’s global average of 0.74 kg/capita/day. Once again, it’s hard to blame individuals for poor waste management systems when it’s clear that companies are responsible for the vast majority of waste production.
Specifically, high-income countries are to blame for the massive industrial waste generation and the rapidly growing e-waste generation.
E-waste, or electronic/electrical waste, is different from other types of waste for many important reasons.
First, e-waste has extremely serious impacts on the environment. It’s not biodegradable and can be very toxic, which can pollute surrounding air, water, and soil for many decades after disposal. It can harm both the environment and human health. It can also emit GHGs, since some parts of the world burn e-waste to recover the valuable metals it contains – or simply because that’s the disposal method of choice.
Next, electronic trash wastes its own tremendous value. The average tonne of e-waste contains 100 times more gold than a tonne of gold ore. And with 50 million tonnes produced in 2018, it’s no surprise that the global e-waste generated is valued at around $62.5 billion USD per year. That’s set to increase as e-waste production is projected to reach 120 million tonnes per year by 2050 – marking a 140% rise. As of 2019, global e-waste is worth more than the GDP of 123 countries, and it could be valued even higher if handled properly.
Lastly, only 20% of e-waste is recycled formally, although we’re capable of recycling much more. Increasing collection/recycling rates, instead of mining, significantly reduces environmental impacts as it cleans up waste streams and avoids digging up more minerals. For example, mining e-waste can emit 80% less CO2 than extracting gold from the ground. More generally, it’s estimated that recycling metals is 2-10 times less energy consuming than smelting new metals from mineral ores.
Note that the electronic components could also just be re-used instead of being deconstructed to recycle the raw materials – which could reduce impacts even further.