Speaker 1: Welcome to brain Stuff from How Stuff Works, Hey, brain Stuff,
Speaker 1: Lauren Voge obamb here. A few years ago, engineer Toby
Speaker 1: McCartney was working in southern India with a charity that
Speaker 1: aided pickers who worked at landfill sites harvesting reusable items
Speaker 1: and selling them. McCartney discovered that the plastic waste they
Speaker 1: retrieved was being put into potholes and roads, dused with
Speaker 1: gasoline and set a fire. When the plastic melted into
Speaker 1: the holes and then hardened, it filled them. When McCartney
Speaker 1: returned to Scotland, he told two of his friends about
Speaker 1: what he had seen. As one of them, Gordon Reid, recalls,
Speaker 1: they decided that it would work better to use plastic
Speaker 1: waste to create a new type of materials specifically designed
Speaker 1: for use in roads. After a year of research, they
Speaker 1: developed a method for transforming a mix of industrial and
Speaker 1: consumer plastic waste into pellets of a new material that
Speaker 1: could replace bitumen, the oil based ceiling material that holds
Speaker 1: asphalt together in roads. Since Reid's company Mcgreeber started operations
Speaker 1: in April of sixteen, the companies recycled plastic road building
Speaker 1: material has been used to build roadways in places ranging
Speaker 1: from Australia to Dubai. Read says we've got roads on
Speaker 1: every continent, and we've had interest from round about fifty
Speaker 1: countries in the world. The company currently is having discussions
Speaker 1: with the University in California about building a test road
Speaker 1: to demonstrate that its plastics are compatible with standards in
Speaker 1: the United States. According to Read, using recycled plastic for
Speaker 1: road buildings sounds simple, but it actually requires a complex
Speaker 1: process to create the right material. He explained, different plastics
Speaker 1: do different things to bitterman. If you use the wrong mix,
Speaker 1: it can actually make the bitterman more brittle. Mcgreeper avoids
Speaker 1: using pet bottles and other types of plastic that are
Speaker 1: easily recycled, and instead concentrates on types of waste plastic
Speaker 1: that might otherwise end up buried in the ground. Read
Speaker 1: declined to go into too much detail as so not
Speaker 1: to reveal too much about mcgreeber's proprietary process. In addition
Speaker 1: to keeping plastic out of landfills, the company says it's
Speaker 1: plastic road materials can save about a ton in carbon
Speaker 1: dioxide output for each town of Benemen that the plastic replaces.
Speaker 1: The company has developed different types of road building plastic
Speaker 1: four different environments. One variety is designed for roads in
Speaker 1: such places as the Middle East, where more tensile strength
Speaker 1: is needed to resist asphalts tendency to deform from heat.
Speaker 1: Another is designed to be more flexible and resist the
Speaker 1: freeze thaw cycle in colder places such as Canada or Scotland.
Speaker 1: Read says mcgreeber's current products are capable of replacing between
Speaker 1: six and twenty of the bitumen in roads, but Read
Speaker 1: is hopeful that within two years improved versions will replace
Speaker 1: as much as Read says that mcgreeber's plastic road materials
Speaker 1: physically bind with betterman which prevents it from breaking loose
Speaker 1: and getting into the environment. In the US, plastic is
Speaker 1: already being used in road maintenance. University of Texas at
Speaker 1: Arlington civil engineer Professor Sahodat Hussein, director of the School
Speaker 1: Solid Waste Institute for Sustainability, has turned to recycled plastic
Speaker 1: as a way to solve the problem of unstable soil
Speaker 1: on highway slopes, which unually can cause the road surface
Speaker 1: to fail. As well. He's developed a technology for taking
Speaker 1: plastic from landfills and then recycling it to manufactured giant
Speaker 1: pins that are inserted into the falling soil to stabilize it.
Speaker 1: Causean explained via email that the recycled plastic pin quote
Speaker 1: has been successfully tested as a laterally loaded pile in
Speaker 1: different highway slope stabilization projects in the state of Texas, Iowa,
Speaker 1: and Missouri. The Texas Department of Transportation has adopted the
Speaker 1: recycled plastic pin as one of their approved slope stabilization methods.
Speaker 1: It takes just three to four minutes to install each
Speaker 1: of the pins in the ground, so an entire unstable
Speaker 1: area can be shored up in a few days. He said.
Speaker 1: Once the pin is installed into the ground, it is
Speaker 1: less susceptible to degradation, which makes it a long lasting
Speaker 1: solution for slope repair. Each recycled pin utilizes about five
Speaker 1: hundred plastic soda bottles. At one of the demonstration sites,
Speaker 1: Hussein's research group puts six hundred plastic pins into the ground,
Speaker 1: making use of some three hundred thousand plastic models that
Speaker 1: otherwise would have ended up in landfills. Coussine thinks that
Speaker 1: the Chinese government's recent decision to ban imports of plastic
Speaker 1: waste for recycling could create an opportunity for US entrepreneurs
Speaker 1: to make road materials. China imported seven hundred and seventy
Speaker 1: six thousand metric tons of plastic waste from the United
Speaker 1: States in two six. Hussein said, I am positive more
Speaker 1: and more roads will be constructed using recycled plastics, but
Speaker 1: he does note that more work needs to be done
Speaker 1: to develop new methods, including full scale testing and life
Speaker 1: cycle analysis of roads containing plastic materials. Today's episode was
Speaker 1: written by Patrick J. Kaiger and produced by Tyler Clang.
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