My impression is that most people have an extremely inaccurate perception of the merits of recycling and throwing things away. Here’s what I believe to be the case, and where people are going wrong.

This list sounds contrarian, but I think it’s actually the boring consensus view among people who are highly informed about waste disposal.

Some of it is common sense, but a lot of it is empirical, so I list a range of sources at the end where you can learn more about each topic.

We aren’t anywhere near running out of space for landfill. The Earth is huge and we are good at digging deep holes. Space will never be a meaningful constraint. (Source: a) Properly run landfill doesn’t hurt the environment in itself.



A badly run landfill site will let items blow away, or toxic fluids leach into the surrounding environment.



But a well run landfill site has a thick, puncture-resistant plastic lining, drainage for fluids, electricity generation from gases produced by decaying matter, active monitoring to avoid water contamination, and more.



Once it’s full, it’s covered over by a thick layer of soil, you can’t even tell it was ever a landfill site, and people can farm on it.



(ADDED 2/8/2019: Tegan Maharaj has helpfully pointed me to an article, which quotes the EPA in 1988 saying that landfill liners ‘will ultimately fail’, and as they develop leaks, will allow acidic leachate to seep out and poison groundwater. The author concludes that landfills are a ‘flawed technology’, or at least, the liners have not been used long enough to demonstrate they’ll continue to function indefinitely.



I’m far from an expert, but while this makes me nervous about how good past landfills are, I’m more optimistic than the author seems to be about how good we can make them in the future.



The article suggests that with it would take 45 years at a minimum for leachate to start breaking through into groundwater, if indeed it does. Large delays like this seems useful to me, as I expect people to be more numerous, richer and technologically advanced in future, and therefore in a better picture to fix such environmental problems.



We can also continue to develop thicker or more robust physical barriers, or layers that expand and re-seal the upper layer on contact with leachate, or better leachate drainage systems. Alternatively, landfill could simply be located in sites with ‘groundwater-free clay geological conditions’. That said, I certainly do worry though that the political incentives to pay more today in order to make landfill safe in the long-term may not be there.



Finally, it really matters how much leachate makes it into ground water, and how much harm this ultimately causes to people and animals living near the surface. That I’m not sure about.



I’d be very grateful to any landfill or environmental engineers who could fill me in on the latest research in this area, so I can figure out how worried to be.)



(Source: a, b, c, d, e) Even really well run landfills are a very cheap way to dispose of our waste. Improved regulatory standards have made landfill in rich countries much better over time, and we can keep working to make them safer and shut down irresponsible or incompetent operators. (Source: a, b, c, d, e) The main downside of sending something to landfill is we miss the chance to benefit from recycling it — but recycling is only sometimes cheaper or better for the environment.



It depends on the item. Metals are hard to mine and easy to recycle, so they should never go to landfill. Plastics are cheap to make and often a pain to recycle — you have to separate into many different categories, and clean them — so it’s sometimes best to just send them to landfill.



I don’t just mean just from a cost point of view. Recycling can be worse for the environment too. By the time someone has picked up that plastic container of peanut butter, driven it to a recycling facility, separated it into its plastic type, taken off the lid, fully washed it out in hot water, and melted it down in a specialised facility, we might have used less energy and produced less pollution just to make a new one from scratch.



Because of these realities and widespread contamination — lids on containers, food still inside them, or paper not being dry— lots of materials that are collected for recycling are never actually recycled and have to be sent to landfill. This is increasingly the case as developing countries start refusing to use their low cost of labour to do the dirty work of figuring out what to do with our recycling.



But for some kinds of plastic in some places recycling is indeed the better option, even if the net gain isn’t that huge. Analysing the total life-cycle cost of recycling vs making new items is very complicated and depends on the specific context. (ADDED 4/8/2019: Some sources are also enthusiastic about the merits of clean paper and cardboard recycling. A common theme seems to be that recycling of materials at the factory or industrial level is very often justified, because you can collect large quantities at a consistent quality, at very low cost.)



(Sources: b, f, k, l, m, o, q, r, s, t, u) The problem of rubbish polluting the sea, rivers and land can be most cheaply addressed by improving rubbish collection and making sure everything gets to landfill.



Almost all of the litter that escapes into nature, especially the sea, comes from fishing ships or poorer riverine countries with bad rubbish collection practices, such as China, India, Indonesia, and Vietnam. Rich countries like the UK or US have rubbish collection rates approaching 100% and are responsible for little new waste reaching the oceans.



Focussing on recycling is a distraction from making sure everything gets collected and safely buried underground — something which many countries already do successfully.



If I were an environmental activist I’d be very excited to work to preventing litter and pollution. But, aside from regulating the fishing industry, that requires a focus on cheap waste management systems that places like Indonesia will be willing to scale up as quickly as possible. I’d bet urban rubbish collection sent to landfill will be the main piece of that puzzle.



(Sources: h, i) Incinerating waste and generating electricity from it is an alternative form of rubbish disposal that is good for the environment and resolves the problem permanently, but is expensive to operate up front. (Source: b) Sending things to landfill isn’t as ‘unsustainable’ as you might think.



You might worry that if we bury all our materials in landfill we’ll eventually run out of them and not be able to use glass or plastics any more. There’s something to this, but it’s overstated.



Burying paper is clearly fine — we aren’t running out of carbon or nitrogen, so we can just grow more trees. In fact growing more trees and burying them as paper is a way of sequestering carbon, which is good.



If we bury metals, we can just mine more aluminium, tin, or iron — we’re not close to running out of any of these. But recycling metals is a good idea, as it’s cheaper and much more environmentally friendly than mining.



Glass is made from silicon, which is one of the most abundant materials on Earth. (Though weirdly we’re running out of sand that’s good for making concrete.)



Plastics come from oil, which we’re gradually exhausting, though not that quickly. We don’t know when oil will truly become scarce — it depends on how much we find, as well as how oil extraction and solar technology advances. Oil has recently become more abundant due to the appearance of shale gas. That said, at some point it must run out. But don’t panic:



a. By the time we start running out of oil for plastic we’ll probably have invented other, maybe better, materials to replace them, just as we’ve switched the materials we use in the past;

b. When oil actually becomes scarce, we can increase our plastic recycling, because by that point it will actually be worth it;

c. We can already make plastic from plants and by then we’ll be much better at doing that. Most oil is used for fuel — just 4–8% goes towards making plastics anyway;

d. Worse come to worst, we can mine plastics and metals from our old landfill sites.



(Sources: k, l, m) Reusable straws and bags are often more resource intensive than single-use ones. Ever noticed that plastic bags and straws are both incredibly thin and incredibly cheap? Almost no resources go into making each one. It’s really kind of amazing.



By contrast, reusable metal straws and canvas bags require something like 10-100x the energy and materials to manufacture, and need regular cleaning so they don’t spread diseases. So unless you use them many times, they end up being worse for the environment. I lose them much faster than that, and have better things to do with my limited attention than remember to bring bags with me everywhere I go, so I just use those old-school plastic bags whenever I get the chance.



A downside of this approach is that, in the process of using lots of these thin plastic bags, you run the risk of not putting one in the bin and it ending up in a river where it goes on to hurt wildlife. But that’s a rare occurrence in the countries I live, and you can just decide not to let that happen. My bags go in the bin 100% of the time!



(Sources: g, j) If we don’t use materials in the first place, we save resources and don’t have to worry about any of the above.



But we also don’t benefit from using the wonderful things we make. Even seemingly trivial things can be important for some people. I don’t use straws because I don’t like them, but some disabled people can’t drink at restaurants without them!



Fortunately humanity is figuring out how to get more and more value out of fewer physical materials very quickly indeed. (Source: n)

While I’m confident the above is broadly right, I also imagine it’s wrong on some factual details, such as which items are worth recycling and in what circumstances. I also wouldn’t be surprised to learn that landfill operators have some trouble avoiding environmental side-effects in practice, or sometimes choose to cut corners even in rich countries.

So I’m excited to find out more from people with greater expertise in waste disposal issues and recycling economics in the comments.

That said, here are my four takeaways from researching how to best deal with our waste:

i) if I’m glad I used something, I don’t feel at all bad just throwing it in the bin when I’m done with it;

ii) I would regard it as a poor use of the effort I put towards improving the world to work on increasing recycling or reducing plastic use in rich countries;

iii) improving rubbish collection in those countries and industries that currently let a lot of it escape into the environment seems neglected relative to its importance;

iv) conventional wisdom on how to deal with environmental issues is surprisingly unreliable.

Sources to learn more

a. Episode 925: A Mob Boss, A Garbage Boat and Why We Recycle, Planet Money (2019)

b. Episode 926: So, Should We Recycle?, Planet Money (2019)

c. How Modern Landfills Work to Protect the Environment on Dumpsters.com (fair to worry this isn’t impartial)

d. How Landfills Work on How Stuff Works

e. Landfill on Wikipedia

f. The Reign of Recycling by John Tierney in the New York Times (2015)

g. Here’s how many times you actually need to reuse your shopping bags, by Trevor Thornton on The Conversation (2018)

h. Plastic waste inputs from land into the ocean, by Jambeck et al. in Science (2015)

i. “Reducing China’s ocean plastic pollution by 3% would be as valuable as getting the USA all the way down to zero.” (2015)

j. Grocery Bag Bans and Foodborne Illness, by Klick and Wright (2013) though while the link is plausible it isn’t proven.

k. Recycling is Garbage by John Tierney in New York Times (1996)

l. Recycling, encyclopaedia entry by Jane Shaw on EconLib

m. Think Globally, Act Irrationally: Recycling, by Michael Munger, 2017

n. How the iPhone helped save the planet, by Andrew McAfee in Wired (2019)

o. “Recycling as currently practiced, with 40% of waste recycled, reduces CO2 emissions by ~3% in the UK”

p. Burn or Bury? A Social Cost Comparison of Final Waste Disposal Methods by Dijkgraaf and Vollebergh in Sustainability Indicators and Environmental

Valuation. (2003)

q. Plastic incineration versus recycling: a comparison of energy and landfill cost savings by W.Reid Lea in Journal of Hazardous Materials. (1996)

r. Lifecycle assessment and economic evaluation of recycling: A case study by Craighill and Powell in Resources, Conservation and Recycling. (1996)

s. Why plastic recycling is so confusing by Wesley Stephenson for the BBC. (2018)

t. A review on which recycling looks like it’s cost saving: Cost effectiveness of recycling: A systems model by Tonjes and Mallikarjun in Waste Management. (2013)

u. Is Recycling Worth It? PM Investigates its Economic and Environmental Impact by Alex Hutchinson for Popular Mechanic (2008)