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The Engineering of Landfills

practical.engineering

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Re: The Engineering of Landfills

#161

Post by maxerickson »

gregmac wrote: post #141
Mistletoe wrote: post #136

Earlier quoted context omitted.

It was so frustrating when a dude at work was trying to bust my balls for not using the recycling for my plastic bottle. I didn’t have the energy or patience to explain to him how our city has single stream recycling and there was 100% chance that bottle was being shipped overseas, dumped in the ocean or something else way more stupid than just being buried in the city landfill.

I worked in an office with recycling bins where everything was just gathered up and thrown in the dumpster with the rest of the garbage. It wasn't just our cleaning people, either: from my desk I could see the only two parking lot entrances and while the garbage truck came weekly, never once did I see a recycling truck.

My town uses the same trucks for both.

Re: The Engineering of Landfills

#162

Post by concordDance »

toomuchtodo wrote: post #126
cogman10 wrote: post #123

Earlier quoted context omitted.

The big problem with plastic waste is getting it to the landfill (or incinerator) in the first place. Once the plastics are captured, I don't see too much benefit in incinerating it beyond freeing up landfill space. But that's really not a major issue as you can always dig a deeper and wider landfill. In fact, a major downside of incinerating the plastic is you end up with greenhouse gasses as a byproduct.

Certainly, you are generating some greenhouse gasses in the process, which is a trade off to ensure immediate waste destruction. To note, you will have to flare methane from the landfill in perpetuity when landfilled. If one is so inclined, internalize the cost of direct air carbon capture into the cost of waste disposal for those emissions. https://www.epa.gov/lmop/basic-information-about-landfill-ga... > Municipal…

Interesting point I hadn't thought of! Had previously thought that obviously things should go straight in the ground to avoid CO2 emissions and hadn't thought about decomposition.

Re: The Engineering of Landfills

#163

Post by lobsterthief »

gruez wrote: post #27
the_gipsy wrote: post #16

Earlier quoted context omitted.

I'd guess that it's cheaper to ship a lot of garbage to developing countries.

Is it? Land is dirt cheap in the US. Surely it's cheaper to bury it locally than ship it half way across the world? Even for the plastic that's being shipped half way across the world, they're ostensibly done for recycling purposes (ie. they're buying the plastic waste), and the unrecycleable plastics end up being mismanaged.

You are correct. In the US at least, land is dirt cheap. Transporting stuff is not cheap. For this reason, it’s common for some US states to ship garbage to other US states for disposal, simply because geographically it makes economic sense.

Re: The Engineering of Landfills

#164

Post by maxerickson »

gosub100 wrote: post #44
mikojan wrote: post #26

Earlier quoted context omitted.

Landfills certainly require more power to operate than that gas scheme can provide later. It all sounds and reads like a fairytale but none of this is sustainable.

This is my argument against recycling. It is not sustainable to recover a tiny amount of energy when balanced with the extra diesel-guzzling truck traversing the neighborhood. All so we can think we're "making a difference" by keeping plastic bottles out of a landfill.

Are you sure? The truck goes a couple of miles on 7 pounds of diesel, how much material is it able to recover in a couple of miles?

Re: The Engineering of Landfills

#165

Post by concordDance »

jenny91 wrote: post #65
flavius29663 wrote: post #61

Earlier quoted context omitted.

Loss of biodiversity and microplastics pollution are even higher in my opinion.

Than global warming and CO2 emissions?!

Geoengineering could maybe bring temperatures back down, but you can't just replant an old growth forest and out all the old plants, fungi and animals back.

If microplastics are behind the fertility drop, reverse flynn effect or obesity crisis they would also be more important in the ~100 year timeline.

Re: The Engineering of Landfills

#166

Post by scoofy »

toomuchtodo wrote: post #126
cogman10 wrote: post #123

Earlier quoted context omitted.

The big problem with plastic waste is getting it to the landfill (or incinerator) in the first place. Once the plastics are captured, I don't see too much benefit in incinerating it beyond freeing up landfill space. But that's really not a major issue as you can always dig a deeper and wider landfill. In fact, a major downside of incinerating the plastic is you end up with greenhouse gasses as a byproduct.

Certainly, you are generating some greenhouse gasses in the process, which is a trade off to ensure immediate waste destruction. To note, you will have to flare methane from the landfill in perpetuity when landfilled. If one is so inclined, internalize the cost of direct air carbon capture into the cost of waste disposal for those emissions. https://www.epa.gov/lmop/basic-information-about-landfill-ga... > Municipal…

While I might be wrong, I seriously doubt the plastics creating the methane emissions you are referring to. That is almost certainly the organic matter.

I have no idea how you think plasma gasification -- requiring extreme amounts of energy -- is in any way helpful to our current environmental concerns. Unless we somehow magically start relying on 100% renewables, it seems like landfills are far-and-away the best way to go until we are able to grapple with climate change.

Re: The Engineering of Landfills

#167

Post by raisedbyninjas »

jrmg wrote: post #140
breck wrote: post #56

Earlier quoted context omitted.

> All the garbage produced in the U.S. for the next 1000 years could fit into a landfill 100 yards deep and 35 miles across on each side. > That is, landfills take a trivial amount of space. Damn, I had to think about this for a second, but you are right. How the hell did I not realize this before? Can you please popularize this more? Maybe compress into a pithy phrase.

The supposed triviality of this size is not sitting well with me. What’s described is a 100 yard deep hole. So about 27 stories. It’s 35 miles per side, so 35 x 35 = 1225 square miles in area. That’s bigger than any city in the mainland US[1]. It’s a 27 story deep hole that’s twice as big as Houston. Three times as big as the city of LA, and over half the size of the urban metropolitan LA area[2]. Four times the size…

That's also just the volume of trash. It doesn't include all the support infrastructure present at each landfill or the buffer real estate so that it is not adjacent to any desirable real estate. It's not practical to have a single huge landfill serving the country, so these other factors get multiplied by every actual landfill site we build. Still there are scant few, if any, counties in the U.S. that are so strained on real estate they can't bury their garbage.

Re: The Engineering of Landfills

#168

Post by dhosek »

toast0 wrote: post #142
dhosek wrote: post #13

There’s some parkland adjacent to the La Puente Landfill (assuming I’m remembering the correct landfill along the 60). I remember going on a hiking trip in the foothills nearby back in the 90s and seeing (and smelling) the landfill in operation there. It occurs to me that I’ve not had that many cases where I’ve been able to directly observe a landfill. The only other instance I can think of was visiting a retired for…

In Virginia, they have Mount Trashmore [1], although that's an abandoned landfill, not an active one. [1] https://en.wikipedia.org/wiki/Mount_Trashmore_Park

I spent some time digging and did find a Chicago park that’s built over a landfilled quarry, although it’s all construction waste in the landfill and not household garbage.

https://www.chicagoparkdistrict.com/parks-facilities/palmisa...

Re: The Engineering of Landfills

#169

Post by Mistletoe »

Goonbaggins wrote: post #156
Mistletoe wrote: post #136

Earlier quoted context omitted.

It was so frustrating when a dude at work was trying to bust my balls for not using the recycling for my plastic bottle. I didn’t have the energy or patience to explain to him how our city has single stream recycling and there was 100% chance that bottle was being shipped overseas, dumped in the ocean or something else way more stupid than just being buried in the city landfill.

Based on the single stream comment, I'm going to assume you're describing an experience in North America, and your assumptions are pretty off base for PET bottles. Figure 1 in the linked paper gives the raw numbers for where PET bottles end up. [1] [1] https://onlinelibrary.wiley.com/doi/10.1111/jiec.13496

https://news.climate.columbia.edu/2020/03/13/fix-recycling-a...

Re: The Engineering of Landfills

#170

Post by Hnrobert42 »

gruez wrote: post #118
mikojan wrote: post #75

Earlier quoted context omitted.

> No, you're incorrect. Exactly what statement is incorrect? Adding to that: Statistics show that developed countries are shipping significant amounts of trash into poorer countries. But there is most likely an even higher number of unrecorded cases. Supply chains can be difficult to monitor even within the OECD, and an estimated third of shipments is illegal.[0] [0]: https://environment.ec.europa.eu/news/video-how-e…

>Exactly what statement is incorrect? Your original comment: >> Almost all plastic waste in developed countries ends up in landfills, not the natural environment. >This is horrifyingly incorrect! Developed countries process only some of their trash themselves. I guess you can weasel out of this by claiming that >85% counts as "some", but it's misleading at the very least. Moreover, your statement was trying to refute…

I saw this article in another comment somewhere above. It makes an interesting point that recycled PET demand now outstrips supply and that is partly because curbside recycling is usually too contaminated to be useful. Instead, DRS systems which refund you like nickel per bottle generate much better streams, but they aren't widely implemented.

All that said. I'm not sure which if you is correct.

https://onlinelibrary.wiley.com/doi/10.1111/jiec.13496

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