Secretly Incredibly Fascinating - Asphalt

Episode Date: September 4, 2023

Alex Schmidt and Katie Goldin explore why asphalt is secretly incredibly fascinating.Visit http://sifpod.fun/ for research sources and for this week's bonus episode.Come hang out with us on the new SIF Discord: https://discord.gg/wbR96nsGg5

Asphalt. Known for being pavement. Famous for being hard. Nobody thinks much about it, so let's have some fun. Let's find out why asphalt is secretly incredibly fascinating. Hey there, folks. Welcome to a whole new podcast episode, a podcast all about why being alive is more interesting than people think it is. My name is Alex Schmidt, and I'm not alone. I'm joined by my co-host, Katie Golden. Katie, what is your relationship to or opinion of asphalt? Every time I smell fresh asphalt, I think of elementary school and I think it is because the playground, like for the new school year, they would always put some fresh asphalt down.

I don't know why, I guess just sort of regular maintenance. So smelling asphalt makes me think of the new school year as an elementary school student. And I've never lost that association. You guys had a nice blacktop. I guess I don't have a specific one association with smelling the new stuff because in a temperate place like Illinois, they were just constantly replacing asphalt everywhere all the time. It would just be ravaged every winter and they were like, we're rebuilding all summer. That's how we do it. Yeah. I don't know. It's just a very strong connection. I smell now when I smell fresh asphalt, I'm like, well, better get out my math textbook because it's time for school. Remember pencil toppers? Gotta get those for school supplies. Oddly, I have a much stronger sense memory of pencil toppers, including maybe the taste.

I think I was a weird kid. Yeah. I remember eating erasers and pencil toppers and pencils and pretty much anything that could be put in the mouth. Paper. Sure. T-shirts. Paper, of course. Whatever.

I mean, like the different papers had different tastes. So originally I thought I chose this topic and then I was like checking on stuff in the Discord and I think Discord user and listener Lance Legstrong kind of incepted this one. He incepted you. Yeah. Our previous episode was WD-40, and I was looking back up what people were saying about it. And Lance Legstrong said, quote, WD-40 was one of the only approved cleaners in the asphalt lab I worked in. We literally buy it by the 55-gallon drum.

Wow. Which is just very interesting, and I think it sparked it. I think that's why I picked it. Their doors must be completely silent in that facility. Smooth. You sneeze and a door closes. Everyone just gliding between rooms. How's it going? Tip a coffee, keep gliding. And yeah, there is also one past SIF episode about concrete. We're about to talk about how asphalt pavement is a concrete. So we didn't really cover that there because it felt like a separate thing. We're doing it now.

But join the Discord is the main point. You might incept me. Join it. And make me do something, which is great. So you too can incept Alex. There's a link in the episode description to incept Alex. Do it. Click here to incept Alex. There's a link in the episode description to Incept Alex. Do it. Click here to Incept Alex.

And on every episode, our first fascinating thing about our topic is a quick set of fascinating numbers and statistics. This week, that is in a segment called... 1, 2, 3. Easy as ABC. The segment is stats for free. 1, 2, 3. ABC ABC Katie, you and me, girl Nice. That's a good stats song

because it already has numbers in it. Yeah, it just fits right in. It's like a gliding WD-40 laboratory person. It's frictionless. And that was submitted by Jeff B. on the Discord. Thank you so much, Jeff B. Very first number this week kind of clarifies what this topic is. I think especially for listeners outside the U.S. and Canada.

The first number is four. Because four is the number of common names for this stuff in the English language. Hmm. I know asphalt. Road flavor is the other one, I think. That's two and three. It's two words. Yeah.

Yeah. Pavement. But I thought pavement was another thing. And black floor. I guess we did call it the black top and that's an okay name but I it's very like caveman seeing it for the first time like black on top it's it's a weird thing to call it anyway uh ground is flat and black yeah and so it turns out there's four names for this, partly because the American use of the word asphalt can mean two separate things. I know that's a lot of numbers and confusing, but we'll explain.

Okay. I only know one asphalt. It turns out the U.S., there's two things we call asphalt. One of them is a sort of raw crude oil, a very heavy crude oil that can bubble to the surface of the ground. The American Chemical Society calls it a dark brown to black cementitious material. Cementitious. What does that mean? It means it can be a cement in concrete, because the other form of asphalt is a concrete where this raw petroleum, this raw oil is one of the ingredients. And if people have heard the concrete episode, we talk about how

any concrete is a mixture of two things. It's a cement and then it's a solid aggregate. So like that gray cement, that's the wall of a building or a parking garage Like that gray cement that's the wall of a building or a parking garage is a mix of a paste and rocks or sand. Asphalt pavement is a concrete. It's just a mix of a cement made of this sticky petroleum that we also call asphalt. And then they mix in something solid. That's how we get pavement. So it's kind of a synecdoche. So it's kind of a synecdoche. We call asphalt the thing, the whole thing, but then it's also just the, they call it bitumen, which is spelled B-I-T-U-M-E-N

and sounds a lot worse than it is. Yeah, I like our choices here. Asphalt or bitumen. Yeah, it sounds like I'm angry at someone on a street, but I'm not. Yeah. It's just called bitumen. It's a clean show, folks. Yep. On this show where I'm not allowed to do bad, naughty words.

Except bitumen. That's not a naughty word. Bitumen is just a component of asphalt. Yeah, it's a heavy crude oil. And most scientists call the oil bitumen. And most scientists call the oil bitumen. One famous deposit is in Western Canada, the Athabasca oil sands that has been depicted in stuff like the book Ducks by Kate Beaton. And then there's also the old word pitch and the old word tar. Yes. Are also words that can be for one or both of these things or can be for other stuff.

So asphalt, bitumen, pitch, and tar are all the topic today, if that makes sense. And we're going to talk about both kinds of things because that's the U.S. use of the word. Right, right. So just the weird black crude thing that bubbles out of the ground and is a byproduct of, I guess, crude oil, as well as the actual surface thing we put on the ground. So cars go on it good. Exactly. And it also turns out a relatively U.S. specific use is roof shingles are often made of asphalt. And that's the other big commercial use of it and other big processed

product oh yeah i guess i never thought about that but yeah there's like little those little squares and then it's got kind of a rough asphalt texture texture on the top and then they get really kind of melty when it gets too hot yeah i guess i never really made that connection but you're right yeah it's just that thing. So it works out. Yeah. And yeah, and there's also a lot of ways to make this pavement version, the concrete version. Next number here is 2017, because that is when a team of scientists did a study and

found that when you're making asphalt concrete, the solid aggregate can be cigarette butts. What? You can mix this oil with cigarette butts and get an effective asphalt concrete. Okay. So, hmm, like, are you just going to see a bunch of cigarette butts sticking out of the ground then? The system even kind of contains the chemicals in cigarette butts that can pollute the ground. So I think they're very hidden in it.

It's really normal looking. And I couldn't find examples of people doing this on a large scale in regular construction. I see. I see. But in theory, you could have a factory where you have a bunch of people smoking and then throwing the cigarette butts into the vat and just like making people chain smoke so that we can create enough cigarette butts to pave the entire interstate system. Right. That's what construction workers are doing on what appear to be breaks. They are actually doing one of the steps. They never take breaks. It's great. I don't pay you to sit around and not smoke. you to sit around and not smoke. And then also, yet another word here for the stuff we have is tarmac. Because it turns out tarmac is a combination of the word tar for the oil stuff,

and then the last name of a scientist named McAdam, who helped develop a way of making asphalt concrete out of it. And apparently in the UK, tarmac is a pretty common word for all pavements. In the US, we mostly use it for airplane runways. Yeah, I've only heard it in the context of airplane runways. Like, we are on the tarmac. We're waiting on the tarmac. We haven't left the tarmac yet.

It's been two hours and we're still on the tarmac. Yeah, and an interesting story about that leads us into our first takeaway for the asphalt episode. Because takeaway number one... Asphalt pavements is barely a solid. Hmm. It turns out this concrete where it's the oil mixed with something solid it can very easily melt or turn into a gooey substance at any time if it takes in a surprisingly modest increase in temperature and that happened to a plane it got stuck on the tarmac like stuck the wheels down into the tarmac oh dear oh dear was everyone okay dear. Was everyone okay? Yeah, it seems like they were.

The story of it is in the summer of 2012, a flight got held at DC's Reagan Airport for three hours. Oh, my God. And did not move out of that spot on the tarmac for three hours. And it was a hot summer day. And so then the plane sank into the tarmac. And when they wanted to go, they couldn't drive out of that muck. Oh, my God. The stories from the Atlantic, they don't say if people like evacuated, but I would think they would. The plane's just stuck and you want to get out of there. That is my nightmare. Like, first of all, waiting on the tarmac for that long in the heat, and then the tarmac eating the plane. Yeah.

You are part of D.C. Reagan Airport now. Like, oh, no. Not even Dulles? I don't know. I don't have a preference. That's just the joke. And, yeah, and that's all because of the chemical properties of the concrete version of asphalt, where it's a mix of two things.

And we use this all over the modern world. Apparently, about 45% of constructed things in the United States, in terms of surface area from above, is paved roads. And then more than 90% of those are paved with asphalt. It's a lot of our picture, if you're looking from space, is asphalt. Beautiful. But also, why do we use asphalt instead of concrete when we're making roads? Because it seems like concrete doesn't melt in the heat.

So what are the beneficial properties of asphalt other than that beautiful smell of fresh asphalt that is so good. Right. Unfortunately, the melting is why we use it too, because it is very easy to sort of lay out on the place you're building a road, because when you're using it in its hot form, it is melty. The melty is helpful when you're constructing, and then unfortunately it can melt after you've done the construction. Melt on your roads, not in your hands? Is that the tagline for asphalt? So do they just kind of spread it out like cake batter or something and then let it dry? In some cases, yeah.

And that's why we use so much of it. The Atlantic says that it is viscoelastic. Viscoelastic. Viscoelastic is a technical term, meaning it can always melt into something stretchy and cool back into something more solid. Is that why VSCO girls had all those elastics? Does anybody remember VSCO girls or is it just me?

I feel like that happened in like 2017 for like a minute and then they were gone. I laughed because I remember it's an internet trend that I don't remember what it is. Hydroflasks and hair elastics is what I remember. Scrunchies. Scrunchies and hydroflasks and hair elastics is what I remember. Scrunchies. Scrunchies and hydro flasks. Fisco elastic girls. Yeah. And so the U.S. uses this all the time.

And in that plane example, you know, a plane's heavier than a car. So that's part of how we got this situation. Checks out. Also, it took a surprisingly not that hot day to do this. Apparently on that day, the plane sank. The temperature was only slightly above 100 Fahrenheit or around 38 Celsius. That's a hot day, but it's not totally out of the ordinary. And so this can happen with asphalt. If temperatures are high enough and the sun beats down on it, the temperature of the actual asphalt can be hot enough to just turn into goo under you. Right. And yeah, presumably you'd have to be a plane sitting in the same spot for a while to start sinking. Like if you're running down the runway, you're probably going fast enough such that you're not sinking downwards. But, you know, that is a concern, especially as things, you know, get a little hotter. And also, tragically, this current summer

2023, there have been a few reports in Arizona and Nevada where people were checked into burn units of medical facilities because they either touched or fell on hot enough asphalt. And, you know, and that can happen in various places in the world if it's just hot enough. So is that like if they say they fell on like dirt versus asphalt in that heat, would it be hotter to fall on the asphalt? Is the asphalt sort of like storing the heat differently in a way than like, say, just like sort of hot sand or hot dirt would store it? In general, yeah. And it's partly the black color of it just absorbs so much energy from light. And then also the fact that one of the components is petroleum, like hot oil is really burny is a highly scientific thing I'm saying.

It's very burny. Yeah. Yeah. So it is a it's it can turn very easily into sort of a hot goo because I remember like from history class that one of the classic punishments is tarring and feathering you, like coating you in hot tar and then pouring feathers on you, I guess, to embarrass you. And on top of giving you burns all over your body, it was like used as a method of torture slash punishment to like burn you with hot tar. Yeah, that was a thing. And also those words tar and pitch are confusing because they can also be substances made from plants. Like not not the way oil is plants where many years went by and it changed under the ground.

Like you can also turn current living plants into that. And so those words are both relatively archaic for what this stuff is. I see. So the the tar that one would use to tar and feather someone is not the same sort of tar that is equivalent to asphalt tar? Yeah, it could be, but it's harder to get, at least back then. And so it usually wouldn't be. So they wouldn't waste it on like tarring and feathering someone unless maybe there were uh nobility who was being tarred and feathered and punished oh they're like is this raw bitumen oh wow the real bitumen for me all right hey and and stick into those old words for a little bit uh the next number here is 10 million tons. 10 million tons. That is the asphalt quantity in the La Brea Pitch Lake. The La Brea Pitch Lake is a large asphalt lake on the Caribbean island of Trinidad. Okay, I was going down the wrong road for this because I was thinking, you mean the La Brea Tar Pits? But no.

Yeah, they're similar things. And again, this is another way pitch and tar are words that just get thrown around because they're both basically deposits of asphalt that are bubbling up from the ground. It just turns out this one in Trinidad is unbelievably humongous. this one in Trinidad is unbelievably humongous. It is 100 acres wide, 250 feet deep, and contains 10 million tons of raw bitumen. Wow. Are there a lot of like skeletons in there? Apparently not really. And it's more of an interesting site because people have been able to study thousands of years of native use of it. The UK National Museum at Liverpool says there are human archaeological sites dating back at least 2,500 years at the edge of the Pitch Lake because peoples like the Taino and the Kalinago recognized the usefulness of this and used it as an adhesive and other handy resource in their society. Because it's just right there. You just scoop it up with tools.

Yeah. It's just sort of a, it's like a glue lake. Basically, yeah. And they have the biggest one in the world. It's a real useful resource on Trinidad. It's interesting because I know for the Labrador pits, there are lots of skeletons in there, like of saber-toothed tigers, of wolves, of mammoths, and so on. So I wonder why there's a difference in terms of like, or if there is a difference in how many animal, preserved animal bones are found in the tar pits. Yeah, because there's also the connection of this La Brea name is colonial.

It turns out La Brea is Spanish for the tar. Ah, okay. So that's the reason the name got applied. And I was the same way between paleontology and formerly living in Los Angeles. I just read La Brea as a street and area in Los Angeles and also dinosaur stuff, but it's not dinosaurs. area in Los Angeles and also dinosaur stuff, but it's not dinosaurs. So saying La Brea Tar Pits is like saying the tar tar pits. Yep, that's right. Okay. Yeah. Turns out.

And yeah, the next number here is about 3 million because we've found about 3 million fossil specimens in the La Brea tar pits in the middle of Los Angeles, California. Yeah, and there's still, to this day, a giant mammoth and a baby mammoth just kind of like floating in the tar pits, made out of plastic, as they were back in the day. Yeah, yeah. No, it's very cool to visit. I've been there a few times. The smell is very good. Yeah, it has a couple of different gases going on. It smells like rotten eggs because of a hydrogen sulfide gas

that emanates from this tar. And then it also often bubbles because of trapped methane gas underneath it. It's a very lively chemical experience. It is. The actual tar pit, like you look at it and like there'll be a big bubble that forms and then pops. It's fascinating. Yeah. And sort of, I don't know, meditative, I guess. You can just stand there, huff the rotting egg fumes and look at the bubbles. Yeah. And it's also still a very active scientific site. Mental Floss says that paleontologists do digs there every day of the year except a couple of holidays.

And they're just continuing to find new things in there because apparently at least five million years ago, a lot of marine plankton died there and their bodies became petroleum. But then this became land above the water. And then during the last 50,000 years, megafauna like woolly mammoths and saber-toothed tigers, and also birds, that's the closest you come to dinosaurs. But all of that got stuck in this above ground asphalt. Technically, birds are dinosaurs, Alex. But I just feel different. So I think you'll find they're not. So the surface must have looked kind of okay until it wasn't.

And then that's how they got stuck. Yeah, because it's a set of different pits as well. It's not this one giant Trinidad lake. And so that's probably part of how this happened. Something got chased into it or something. And like Katie was saying, if folks go to this tar pit place, it's awesome. And also there's a bunch of big models of like animals fighting, because that's sort of the story we've told ourselves about the tar pits, that they got

chased into them or something. Also, if I remember correctly, there was some theory that there would be some, some animal would get stuck in the tar pit, like say a mammoth, and then more animals would get stuck in the tar pit because they would try to go and scavenge the dead mammoth. But now they're stuck in the tar pit. And then another to go and scavenge the dead mammoth but now they're stuck in the tar pit and then another scavenger would be like look at this animal salad i'm gonna go see if i can eat some of that but then they get stuck in the tar pit so if i remember correctly sometimes they'd find sort of like clusters of fossils where you get this like sort of animal pile up just a diorama of the food chain. Wow.

Okay. That's amazing. And we have a couple more big takeaways for the episode. And the next one is also about animals. Yay. Because takeaway number two. There are deep sea asphalt volcanoes where the asphalt feeds an entire marine ecosystem. I love deep sea food chains because it always starts with something that seems like it should not be edible by anything alive.

But then you've got some kind of little guy, some kind of little bacteria who can do it. And then suddenly you've got all sorts of weird, freaky looking animals. Exactly. That's exactly what's happening. There are weird microbes that eat the gases from asphalt. And from there we have an entire ecosystem, basically in a deep sea, ocean floor, oil spill coming from the earth. This is a general rule for colonizing things. So like whether it's a rock covered with

moss and then you see other plants growing out of it or a deep sea vent, usually you start from like really small to larger and the small thing starts to either neutralize the thing that is toxic or converting it into organic matter that can actually be eaten by something else. And then you have a chain of animals all dependent on that tiniest little guy, like a bacteria or a microbe, who is converting this thing that should be toxic into something less toxic. And in fact, there are deep sea animals that not only do they eat the bacteria or eat the things that eat the bacteria,

they will be like covered partially in the bacteria, which can help protect them. Wow. What an intercombination of all these skills. Yes. It's true synergy happening down there. And I assume I'm phobic of 99% of the animals we just described, but you know, it's fine. It's cool. If you can picture in your head, the Yeti armed crab, what do you think? Do you think you'd like that, Alex? I mean, I really like Yetis, especially in the animated film Smallfoot, where they're very cute.

So I'm kind of into it. I'm kind of on board in that way, but it's probably crabby. I don't know. What about the volcano snail? Oh, Gary from SpongeBob. Great. It's good. It's really good.

Yeah, and these volcanoes are apparently inactive. The key source here is a piece for The Atlantic by the great Ed Young, who covered 2017 studies of inactive asphalt volcanoes under the ocean in the Gulf of Mexico. And so these are, you know, prominent locations in the seafloor and kind of covered in raw asphalt, sort of like how it bubbles up in tar pits. And an amazing amount of marine life is thriving there, mainly because there are microbes who have adapted to consume the hydrogen sulfide or consume methane or both. And those are the gases we just talked about being coming out of the Lobreotar pits. Yeah, it's amazing how you find these like very dense oases of life down

due to these microbes that can eat these probably otherwise inedible gases or elements. And then you'll have things where it's like you have a whole vent covered in weird-looking shrimp or something. It's really incredible. That's fun. Apparently, hydrothermal vents are broadly similar to this situation, and that it's a bunch of weirdos who have made the best of this too hot place. But in this case, it's too asphalty, you know? Mmm, delicious.

I love this story because I truly only think of petroleum as being negative for animal life. Like you think of seabirds covered in an oil spill. And then under this part of the Gulf of Mexico, there's an entire food web. Apparently these volcanoes have tube worms, sea lilies, corals, clams, crabs, and entire schools of fish. Wow. And it's particularly rich for species of mussels. Apparently, there's over 50 different mussel species in Gulf of Mexico, asphalt volcanoes, and hydrothermal vents. One scientist just looking into this in general is Dr. Nicole DeBillier of the Max Planck Institute for Marine Microbiology. And she says that these volcanoes are so rich in mussel diversity, it's almost like the finches on the Galapagos Islands that Darwin studied in terms of how much extreme diversity there is in such a small space. But this one's even weirder because it makes sense that a bird would live on a nice island. This is mussels living in a natural oil spill.

In what way are they diverse? Like their shape, their size? Both and genetics, apparently. Yeah. Cool. I guess Darwin's finches is a little catchier than Darwin's muscles. Except I guess Darwin's muscles does make it sound like Darwin's inviting you to the gun show. There goes Katie Turbo Muscles Golden making other people muscular. like a Hans and Franz figure, pumping people up. I see. And then one other thing about this situation, humans are very excitedly studying it, you know, because this is just the earth bubbling up this asphalt and then nature doing something with it.

bubbling up this asphalt and then nature doing something with it. My favorite part of studying this is a quote from Dr. Dubillier, who says, quote, when the submersible comes back up, it reeks of petroleum and it's filthy. We have to clean it with WD-40. It's the only thing that works. What? So last week's show about WD-40, it's coming together. I feel like we're going to start seeing WD-40 everywhere now that we did an episode on it.

It's going to be the cocktail effect where it's just like, and this is like, did you know that this is made of WD-40? And we use this WD-40 for that and this. And I'm going to look at my hands and they're slowly going to melt into WD-40 and everything's going to be WD-40. Your fingers are the straws. So many straws. Oh, boy. Yeah, that was astonishing. So it's all come together for folks who listen weekly.

There you go. With that nice little alley-oop there, we're going to take a quick break before we do a couple more takeaways. Hey, it's Alex. Quick, quick mini plug or even just heads up about SifPod.store. That is the website name I chose because you can get a domain name that ends in.store. If you go to SifPod.store I'm Jesse Thorne. I just don't want to leave a mess. This week on Bullseye, Dan Ackroyd talks to me about the Blues Brothers, Ghostbusters, and his very detailed plans about how he'll spend his afterlife. I think I'm going to roam in a few places. Yes, I'm going to manifest and roam. All that and more on the next Bullseye from MaximumFun.org and NPR. JV Club with Janet Varney is part of the curriculum for the school year. Learning about the teenage years of such guests as Alison Brie, Vicki Peterson, John Hodgman, and so many more is a

valuable and enriching experience. One you have no choice but to embrace because yes, listening is mandatory. The JV Club with Janet Varney is available every Thursday on Maximum Fun or wherever you get your podcasts. Thank you. And remember, no running in the halls. And we are back. And the next takeaway here is about the asphalt concrete sense of this again. Takeaway number three. create sense of this again. Takeaway number three. Some asphalt roads might pollute more than the cars that drive on them. Well, shucks. Gosh, darn it.

Yeah. I did. I like, I did want to put this after the surprising thriving asphalt ecosystem, because as bad as the pollution is, it is also a substance that naturally comes from the earth. And we need to use it right, but it is kind of better and worse than I expected in terms of its impact. is a piece for Smithsonian Magazine by Diane Lugo, because in 2020, a team at Yale published in the journal Science Advances about what happens when asphalt concrete pavement gets overheated. Right? Like we know it gets gooey, but does it do anything else? And we knew that it probably emits some chemicals, maybe some amount of pollution. But according to this Yale study, asphalt can release large amounts of polluting compounds into the air. And when the temperature of the asphalt goes from 104 Fahrenheit to 140 Fahrenheit, the pollution doubles. So that's kind of the key temperature range. And the asphalt can be

much hotter than the air around us. So that's a not uncommon temperature for asphalt. I mean, that seems bad given global warming and that there seems like there would be sort of a runaway effect where as the planet heats up, more asphalt leads to pollution. Do you know if the pollution has any kind of greenhouse effect? They think yes. Yeah. Oh, great. Good, good, good, good, good, good, good, good. And this kind of fits in with knowledge of urban heat islands and other ways we are finding that roads and secondarily asphalt shingles can overall contribute to pollution on the earth. That's bad.

I don't like that. And the weirdest part is that in a few regions, there might be roads that pollute more than the cars on them. And they think one example might be Southern California. Hooray, my home area. Hooray, my home area. It's surprising because our perfect solution to traffic is add more road, which then gets filled with more traffic. And then we add more road.

And then weirdly, that too gets filled with traffic. And so guess what we do, Alex? Probably the first or second thing you said again. We add more road. Yes. Silver lining. One reason for this flip where the roads could pollute more than the cars is that there are cleaner cars now. Like that also sets this up. It's not a great reason, but overall that this one study, and it's just one study, they could be wrong, but they estimate that vehicles contribute between 900 to 1400 tons of air pollution in Southern California, while new paving and new roofing in that region release between 1,000 and 2,500 tons of pollution.

So more, by a substantial amount. Why do we even use asphalt in roofing like what it doesn't seem like that would be very energy efficient either if it's like absorbing all the heat and you've got hot summers in southern california buildings are getting warmer and then you're using more air conditioning why we do that apparently it's sort of like the road reason like there there are other things we could make roads or shingles out of. And some people have clay roofs, some people have metal roofs, but those tend to be more expensive because they last longer and are tougher. So asphalt shingles,

we've found we can put a bunch of them up and replace them with some regularity. I see. I see. Well. And apparently in a lot of Europe and in a lot of Asia, they do more tile shingles and more roofing with other materials. It's sort of a U.S. and Canada thing to do the asphalt shingles. How does the pollution work? Because it seems like it releases when it gets hot. So if we say we took away some of the roads and the roofing, could we like safely dispose of them without it causing more pollution? Or are we already kind of screwed? Like, would we just need to stop doing it now and hope we don't do more damage? I wondered about that and couldn't find a great answer. It seems to be sort of like a lot of our petroleum use where it's simply bad for the environment.

I see. But if we buried it in a big enough hole, maybe. Oh, and then we tell ourselves to forget it's there. Forget it's there. And then we surprise ourselves with an oil find, like the Beverly Hillbillies. Like, oh, wow, look. Look at all this. It's like a dog that keeps getting surprised by its own ball that it put between its feet. But I thought, so we got those bacteria that eat asphalt in the ocean.

What if we put all the asphalt in the ocean? Huh? Huh? Yeah, anything that would take more of this out of sunshine is basically a net positive for the environment. Holes work. They work. Put it in a hole.

Yeah, because it's just hard to imagine an empty road as causing pollution. You think you've got to wait for a huge truck to come through or something, but the empty one can too. I see. And then there's also a silver lining where in the last 20 years or so, we've found a less polluting way to construct asphalt pavement and asphalt roads, which is nice. Like once they're there, they pollute in this way we described. And there is some pollution in laying it down, but I'm going to link National Geographic because it's a pretty technical difference. pretty technical difference. The basics are that there is a relatively new way of mixing hot asphalt called warm mix, where you do a much lower temperature. The old kind is called hot mix. And if you do warm mix, that's a lower temperature, releases less chemicals, it's also safer for the workers. And the US in particular has been a leader in that.

and the U.S. in particular has been a leader in that. Apparently, we began using it in the early 2000s, and we went from laying down less than 100,000 tons of asphalt in 2004 to about 47 million tons in 2010 in this new warm mix way that is better for the environment. So some new construction is better than it has been. So is the warm mix also more resilient to the just like continual release of pollution? Like as it heats up from the sun, like is it more stable such that it doesn't release chemicals when it gets hot? Unfortunately,

it functions about the same once we lay it down, like both in terms of road toughness and also pollution. Yeah. So this is a piece of good news for the construction phase, but not for the sitting around. That's too bad. Put it in a hole instead. Speaking of burying things for the future, the last big takeaway of the show here is about an amazingly long history of asphalt construction. Because takeaway number four, humans have been using asphalt for massive public works projects for thousands of years.

Hey, look at us go. Yeah, it turns out the raw bitumen kind is something that people have used for a long time. But we didn't have cars thousands of years ago, Alex. So why do we need asphalt? And at least one of these stories for carts and stuff. But it's true. It's not just for pavement, for roads. Yeah.

stuff. But it's true. It's not just for pavement, for roads. Yeah. Would they ever, would hot asphalt back in the day ever eat like a mule that stands there too long? They should have let the mule take off. That was the mistake. It was scheduled. Because yeah, this substance, like we've been saying, it bubbles up to the surface of the earth in a few locations. And in pretty much every location it does that, we've found thousands of years of people using it, just gathering it and doing stuff with it. We already mentioned the massive asphalt lake on Trinidad. There's also the Athabasca oil sands in Western Canada. The name Athabasca is a Cree native word, and there have been native people there a long time. And they've used natural asphalt to bind and seal canoes.

There's also records of people heating up asphalt to create fumes to drive away mosquitoes. Which is kind of clever, especially if that's the chemicals you have way back when. Yeah. I mean, if I was a mosquito, that wouldn't drive me away. Again, I think I'm unhealthily addicted to the smell of asphalt. Right. It's a big problem, but we love it. We love it.

And also with modern Southern California, I'm going to link an Atlas Obscura listing about the Carpinteria tar pits, which are northwest of the La Brea tar pits, but modern Southern California is full of tar pits. And so peoples like the Tongva and the Chumash have used asphalt for all sorts of purposes for a long time. Everything from mounting arrowheads to sealing containers of water. mounting arrowheads to sealing containers of water. Did they ever use it in construction, like creating lodgings or any other kind of infrastructure? Them, not so much that I can find. There's lots of different peoples all over the world using asphalt as a waterproofing sealant or an adhesive to bind stuff together. So maybe on small structures they did. But there's some other stories here

about ancient peoples in West Asia and North Africa building huge stuff. And the source for those is a book called Paving Our Ways, which is by a group of engineers and researchers. It's written by Maxwell Lay, John Metcalf, and Kieran Sharp. But they say that there's a couple

monumental public works that were made with asphalt very long ago. The oldest might be 5,000 years old at a city that we call Mohenjo-Daro in the Indus River Valley in present-day Pakistan. So what were they building? Roads? What were they building with asphalt? And their biggest structure, we don't know exactly how their culture worked, but they seem to be very into water and especially having big tanks of water available. Well, that's useful generally. Yeah. Like it could have been drinking water, sanitation could have been religious. Like we don't really know, but there's one structure

in Mahenjo-daro that we call the Great Bath today. It's considered one of the first public reservoirs and water sources that a city has ever built. So it's an ancient water tower, essentially. Yeah, kind of. Yeah. And that's awesome. Were there ancient Animaniacs in that? That's awesome.

Were there ancient Animaniacs in that? Mahenjo-daro rhymes with some of the Animaniacs names. That's the thought I had. But I think that's a coincidence, probably. That's my guess. That's my guess. Can't verify it. And this great bath, it's made of a lot of brick and then some stone too. Apparently the joints between that and

also some of the side surfaces of the bath were waterproofed with asphalt, the raw crude oil asphalt, because it works for that and maybe impacted the quality of the water, but it definitely held the water in. Look, at that point, then you're seeing Animaniacs, and that's just good fun. I want to see them all the time. It's a great show. Ever since you mentioned them, the theme song has been playing in my head. Yes. And it's not due to the asphalt fumes flowing in from outside.

And then the other big public works story is about 4,500 years ago, ancient Egypt. Oh, the Egyptians. They love to build stuff. They did a lot of stuff. They made triangles. Yeah, and apparently they used asphalt as a component in paving roads, usually for construction of temples or monuments or giant triangles like pyramids. For their sarcophagomobiles. Wait, no, let me do that. For their sarcophagomobiles. Wait, no, let me do that again.

Sarcophagomobiles. What if I was like, those vehicles pollute so much, there's huge smokestacks on the sarcophagus? Like, why? And there's also kind of vaguer records of Mesopotamians doing something similar. kind of vaguer records of Mesopotamians doing something similar. King Nebuchadnezzar of Babylon was said to have made a road, quote, glistening with bitumen and burnt bricks. And both these societies were taking little pieces of chiseled rocks or loose bricks and then using the asphalt or bitumen to bind it together.

And that's pretty much how we do pavement now. There's differences in the technique, but that's the general idea. That's so interesting to like, because when I picture an ancient culture, when I think of a road, I'm thinking cobblestones, I'm thinking bricks, maybe dirt or something, but not really asphalt. And so I think like if you time traveled and you saw like an asphalt road, you'd be like confused because you thought you'd time traveled, but here's an asphalt road, which you're pretty used to as a modern person. Yeah, exactly. It just doesn't feel like something they would do at all. And asphalt has been with us for more than a

century in the modern way for pavement but i do tend to imagine it as being super recent i'm like no only us and yesterday is my thought before researching but it turns out you know 4 500 years or so doing that huh so you know they didn't build nearly as many roads as us and cause the ecological problems but they started it they started it i'm gonna blame them yeah they they it was them their fault not ours yeah damn you nebuchadnezzar why did your beautiful roads make us pollute the planet yeah the quote is that it glistened with bitumen. It really seems like he went, it makes it sound like he got real wild with the amount of bitumen. Yeah. Like it was too much.

It was absolutely b******* with bitumen. Folks, that's the main episode for this week. Welcome to the outro with fun features for you such as help remembering this episode with a run back through the big takeaways. Takeaway number one, asphalt pavement is barely a solid. Takeaway number two, there are deep sea asphalt volcanoes where asphalt bubbles up and feeds entire marine ecosystems. Takeaway number three, some asphalt roads might pollute more than the cars that drive on them. pollute more than the cars that drive on them. Takeaway number four, humans have been using asphalt for massive public works projects for thousands of years. Plus a lot of numbers, in particular how asphalt and bitumen and tar and pitch are all kind of the same thing but kind of not and are generally the topic this week. Also a lot of La Brea Tar Pits stuff and other tar pits and lakes too.

Those are the takeaways. Also, I said that's the main episode because there is more secretly incredibly fascinating stuff available to you right now. If you support this show at MaximumFun.org. In addition to SifPod anniversary posters and all kinds of other benefits, members get a bonus show every week. In the bonus show, we explore one obviously incredibly fascinating story related to the main episode. This week's bonus topic is the unique and strange situation of asphalt highways in Australia. Visit CifPod.fun for that bonus show, for a library of more than 13 dozen other secretly incredibly fascinating bonus shows, and a catalog of all sorts of MaxFun bonus shows. It's special audio. It's just for members. Thank you for being somebody who backs this podcast

operation. Additional fun things, check out our research sources on this episode's page at maximumfund.org key sources this week include all sorts of digital writing from the american chemical society atlas obscurus smithsonian magazine national geographic and the atlantic to name a few also museums like the uk national museum at liverpool and the La Brea Tar Pits in California, plus the book Paving Our Ways by Maxwell Lay, John Metcalf, and Kieran Sharp. That page also features resources such as native-land.ca. I'm using those to acknowledge that I recorded this on the traditional land of the Canarsie and Lenape peoples. Katie taped this in the country of Italy. And I want to acknowledge that in my location, in many other locations in the Americas and elsewhere,

Native people are very much still here. That feels worth doing on each episode. And join the free SIF Discord, where we're sharing stories and resources about Native people and life. There's a link in this episode's description to join the Discord. As I said earlier in the show, the Discord also lets you incept me about episode topics, and we're talking about this episode on the Discord. Would you like a tip on another episode? Because each week I'm finding you something randomly incredibly fascinating by running all the past episode numbers through a random number generator. This week's pick is episode 39. That is about the topic of playing cards, and if you

visit the SifPod account on TikTok or on Reels, you can see a little video where I share a fun fact about playing cards. I recommend that. Also recommend my co-host Katie Golden's weekly podcast Creature Feature about animals and science and more. Our theme music is Unbroken Unshaven by the Budos Band. Our show logo is by artist Burton Durand. Special thanks to Chris Souza for audio mastering on this episode. Extra, extra special thanks go to our members. And thank you to all our listeners. I'm thrilled to say we will be back next week with more secretly incredibly fascinating.

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