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Municipal waste

In this video Dr. Nathan B. English talks about Municipal Waste.
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Welcome to step two of the last week of the Beginner’s Guide to Environmental Science. And this week we’re covering waste. And we’re going to start with municipal waste. But before we begin on municipal waste, we’re going to just cover a few of the different kinds of waste and the different waste types that we’ll be talking about for the rest of the week. So you probably know this already, but waste is any unwanted material or substance that results from human activity. And this includes even our natural effluent, things like that. But a lot of it is what we might consider unnatural waste. So plastics, glass, manufactured goods, food, crops, things like that.
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And it generally breaks down into two types of waste that human activities result in. And that’s degradable waste and non-degradable waste. And as you might intuit, degradable waste is anything that can be broken down with time. So plant and animal sources, so food scraps, green waste, even things like wood. And these are things that are broken down on human timescales, not over geological time. Now, just because it can biodegrade doesn’t mean it will. And there’s still lots of food sitting out in landfills that from 20, 30 years ago, that hasn’t degraded because the lack of oxygen in landfills prevents bacteria
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from breaking down those biodegradable materials. So even though it can biodegrade, doesn’t necessarily mean it will, especially if it requires aerobic organisms to break it down. Now, anaerobic bacteria will break down degradable waste. And when they do that, they’ll produce methane. And oftentimes, landfills will harvest that methane and use it on on-site power generation. Just kind of cool, but it doesn’t always happen. Non-degradable waste is waste
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that cannot be broken down by organisms: plastics, metals, glass, toxins, cigarette butts. Now look, over time, geologic time thousands, tens of thousands of years, yes, it might degrade, but we’re talking about waste on human timescales. So we should consider the degradable versus non-degradable on our human timescales, ‘cause those are what matter most to us. And most of the non-degradable waste could and probably should be recycled. So plastics, metals, glass, toxins…
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Plastics, metals, glass can be easily recycled. Toxins can be incinerated. Cigarette butts more difficult to imagine a recycle use for those. But lots of other ways can. The main categories of waste beyond degradable and non degradable are the four main types. And these are the ones we’re going to cover this week, in addition to covering some of how they’re disposed off. So municipal solid waste, we’ll talk about today. This is the one you’re most familiar with. Industrial solid waste, may not be as familiar with this. Hazardous waste, we’ll cover the different kinds of hazardous waste and how it’s disposed off, and then wastewater. So you’ll notice that a couple of these revolve around whether it’s solid or liquid.
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Hazardous waste can be both solid and liquid. Wastewaters just liquid.
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Now, municipal solid waste is general rubbish refuse that’s generated in a home or in metropolitan areas. And generally, it should be, and mostly is, non-hazardous. Occasionally hazardous materials will fall into, or will be included in municipal solid waste. And it’s mainly e-waste, things like computers, batteries, electronic items that have been disposed off improperly. It’s from house, yeah. Households, public facilities, small businesses. It includes food scraps, paper, fibers, metals, glass, all the whole gamut of things, green waste, bottle tops, everything. And when we look at what is actually in municipal waste, the largest component by far is biodegradable food scraps and garden waste, the green waste. And this is followed by newspapers and other waste paper.
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Now, that newspapers and waste paper is beginning to decline as people stop buying newspapers and move online for their news. But things like cardboard, and we use paper and a lot of other contexts, and there’s still a large part and a large component of our waste stream. In 2016, world cities generated about 2 billion tons of solid waste. So it’s all of the municipal waste. And that if we average that out across humans,
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that’s about three quarters of a kilogram per person per day. Now, remember that’s an average, and people in developed nations will create rubbish on a greater scale than people in less developed nations. It’s just a matter of affluence, which we’ve talked about in previous weeks. But this is just a nice, handy guide to municipal waste. It sort of talks about the source, the primary components generated, the drivers, excess packaging.(laughs) I always love it when I see bananas wrapped in plastic. It’s like it’s got a (indistinct). Dependence on disposable products, sort of the throwaway society. And I’ll touch on that at the very end. And it’s easy to throw things away, and it doesn’t cost us anything.
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And so there’s really no drivers to prevent us from throwing things away. So that’s an interesting aspect. And because it’s environmental science, you could always examine that from a legal or a social aspect as well.
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Typical disposal strategy right now is, in developed nations, recycling, composting, and sanitary landfill is how it’s mostly disposed off. In some contexts, where land is scarce or appropriate land for a landfill is scarce, you might get incineration. But in many nations, it’s still open dumps, open burning, or just in a ditch by the side of the road. And so that’s sort of the typical ways that municipal waste is disposed off. There is a strong relationship between the income of a nation and the amount of waste per person it generates. So this is a per capita figure. On the bottom x-axis of this graph is the urbanization rate.
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And on the y-axis here is the waste generation per capita in kilograms per capita per day. So kilograms per person per day. And you can see that in high-income countries, the amount of waste generated by people is almost twice as high as the amount of generated in upper-middle income or lower-middle income and low-income countries by income group. And this is true within nations as well. So we see this relationship between waste generation and affluence. And I don’t think that will surprise anybody. When we look at the disposal streams in those different groups, we find that in every group that food waste and green waste are the largest proportion of rubbish and waste. So that’s really interesting. So that’s really common.
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So you can think about this now. If you wanted to focus on reducing waste generation, you’re better off putting a dollar into reducing the amount. You’re better putting a dollar into reducing the amount of food and green waste than you are putting in perhaps a dollar to reduce the amount of metal waste, because food and green waste are the largest component by far in all income groups. Now, if you were going to target a campaign to reduce
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paper waste, paper and cardboard waste, you might target that at high-income people, rather than low, or lower-middle income people, because it would have twice as great effect on a higher income folks if it had an effect. So you can begin to look at some of this and think about what’s different in each of these waste streams. Plastic is a large component of waste in almost all the waste streams, but you’ll notice that rubber and leather is small components. Wood is a small component. It’s more of an industrial, oftentimes more of an industrial waste, and glasses, well, is a small component.
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Now, remember these are models, and model don’t always match the real world. But there is a general trend again in, if we look at GDP per capita, and this is a ten-year-old graph, but still roughly holds. If you look at the actual waste per capita generated versus the GDP per capita, the actual numbers are these little green dots, the model numbers are the yellow dots. You can see that there are some places where a high GDP nation is producing a similar amount of waste as a low-income nation. But in general, the trend is that, the more the wealthier a nation, the higher amount of waste per person.
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And again, that’s not spread evenly or distributed evenly within nations so, because there is income inequality within nations as well. If we look at the projected growth for waste generation, municipal waste generation into the future, you can see that in 2016, it’s about 2.1, and we’ll grow that by about a third by 2050. And that’s a real concern because we are running out of space to put our wastes. And so there should be a real focus on finding sustainable solutions about reducing the amount of waste we generate and recycling or reusing the waste that we generate. And we’ll talk about that later on this week.
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But I just put this up here ‘cause it’s interesting to think about what’s going to happen in the future? Where is all that waste going to go? Now, part of this is because of population growth, and part of this is because of growing affluence. And when I say growing affluence, what’s really interesting, and I think this is really interesting. Again, when we look at waste generation by income group in millions of tons per year, there’s projected to be a relatively small amount of growth in waste generation in upper-middle to high-income groups. Whereas lower-middle income groups, as they become more affluent, will begin to generate more waste.
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And again, this, we can begin to focus on solutions here, instead of trying to get high-income or upper-middle income people to reduce their waste streams further, we get more bang for our buck by finding ways to assist and help lower-middle income people to generate less waste as they become more affluent. And then low-income as well, similar growth, projected growth, waste growth as upper-middle income, high-income. So these are interesting things to think about when we start thinking about waste generation And again, this millions of tons per year. So that’s about 1.2 billion tons of waste generated. Now notice, in 2050, if you add up the upper-middle income and high-income, you get about 1.9 billion tons.
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Whereas if you add up the waste generation from low-income, you get about 1.4 billion tons per year. So that idea still holds that higher-income, more affluence leads to greater waste generation.
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Municipal solid waste is on the rise. We’ve just talked about a lot of this stuff, but I’ll recap it here. And I think I put on here this right-to -repair, because we do live in a society in most developed nations where you basically, if something breaks, you just go out and buy a new one. And lots of manufacturers have been moving to a model where if something breaks, you’re not allowed to repair it, or they’ve made it in such a way that it’s difficult to repair. And so you’re actually, it’s not that you want to throw it out and go buy a new one, there’s no other choice if you want that product.
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And it’s interesting to see that part of this movement to have the right to repair your own consumer goods is a by-product of that is that it will generate less waste. Big moves in Europe to make this happen. You should be able to replace the battery in your mobile phone, because you shouldn’t have to buy a new mobile phone every two years when your battery it degrades, you should just be able to buy the new battery. I don’t need a supercomputer in my pocket. I just need a phone.(chuckles) So it’ll be interesting to watch this right-to-repair movement and to see the by-product of that in the amount of waste generated, especially in the e-waste category.
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Developed nations can afford better ways to collection, disposal, and management, but we also generate more waste. There’s little wheel or opportunity to mitigate the problem. And again, this is a lot this(indistinct), it’s out of sight, it’s out of mind, we simply put our rubbish bins out on the curb each week and it magically disappears. But remember, matter is neither created nor destroyed, that matter goes off to a landfill typically somewhere. And so we do need to pay attention to it.
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And so that is the end of this lecture. And we’ll talk next about industrial solid waste in an article. And then step four and five, we’ll talk about hazardous waste and wastewater. And then later on, we’ll talk about heavy metals and e-waste as well. Cheers!

We begin this week by looking at the categories of waste that we as humans create. We will start with municipal waste, the waste that is generated by households.

Watch Dr. Nathan B. English discuss what the municipal waste we produce is made up of and where it goes. He also examines the demographics of waste production among higher and lower-income nations and how municipal waste generation is increasing across them.

Video guide

Since this video is a little longer than most videos in this course, here is a guide to the topics it covers.

Topic Timestamp
Types of waste 0:15
Municipal solid waste 3:20
Sources and disposal strategies 5:00
Waste generation and affluence 6:25
Future waste generation 9:35
Right to repair 12:00

Now it’s your turn

Given the information that Dr. English provides in this video, what are some ways that you and your household could reduce your municipal waste contribution? What are some policies your government could institute to reduce municipal waste? Share you thoughts in the comments.

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