The Romans invented the method of recycling 2,000 years ago

Excavations have shown that rubbish left outside the walls is not for burial but has been collected, sorted and sold.

The Romans were talented engineers who invented ways to make underfloor heating, sewers and use concrete as a construction material. Now we know they are also masters in recycling.

Restoration of the business plaza, adapted from the book 'Homes and Monuments of Pompeii' by Fausto and Felice Niccolini, 1854-96.

Pompeii is a city buried under the ashes of Vesuvius volcano when it erupted in 79 AD. Researchers have found here the huge pile of rubbish outside the walls is the classification for reuse of garbage.

Professor Allison Emmerson, an American researcher who joined the Pompeii survey team, said trash was piled up along most of the city walls north of the city and elsewhere. Some of the garbage piles are several meters high and include plastic waste and ceramic flakes. These can be reused as construction materials.

Previously, these mounds were thought to have formed when the city suffered an earthquake about 17 years before the volcanic disaster. By the mid-twentieth century, people here had cleared most of these mounds but there were still some new ones that continued to be found.

Current scientific analysis has found that a part of the waste from the city has been moved to the suburbs like modern modern landfills, after which what can be used as materials has been converted back into streets for use as construction materials, for example, as a foundation.

Together with colleagues, Professor Emmerson has learned how the Pompeii built this ancient city. She said a part of the city was built from rubbish, 'the piles of mounds outside the walls are not gathered there for disposal but are collected and sorted and the sale of these scraps takes place next to it. in the walls'.

The suburb of Porta Ercolano outside the northern wall of Pompeii. When excavating the site, archaeologists found ancient debris in and around tombs, houses and shops.

Pompeii was originally a city of beautiful mansions and public buildings, squares, art shops, pubs, public baths and brothels. In addition, the city also has an arena that can accommodate up to 20,000 spectators.

When the Vesuvius volcanic ash poured down, the city was engulfed in darkness and at least 2,000 people died. In 1748, an explorer group discovered that the city was preserved almost intact under a thick layer of volcanic ash and pumice. Even later archaeologists found a whole loaf of bread preserved intact.

Today Pompeii is a UNESCO World Heritage Site. Each year this place attracts about 2.5 million visitors to visit.

Professor Emmerson and colleagues have used soil samples to track the city for garbage collection. The soil excavated by the team has different characteristics depending on where the waste is discharged. Rubbish in places like toilets leaves an area of ​​fertile organic soil. In contrast, garbage that accumulates on the street or the collection piles outside the city over time gradually leaves more sand in the soil.

Differences in soil indicate that waste is generated at the place where it was found or collected from other places for reuse and recycling. For example, some walls were built with reusable materials such as tiles and water jars, even old plaster and plaster. Most of the walls are plastered with stucco outside so no one can see inside of many different scraps.

The researchers believe the earthquake caused these items to be broken and broken, in addition to rubble and the Romans took advantage of these scrap. Pompeii city was also expanded to outside the city walls, so it could not be said that these suburbs were only used as landfills.

Modern waste management methods today focus on getting the garbage out of everyday life, regardless of what happens to the garbage, as long as it is removed. But it was in Pompeii that researchers discovered a completely different way. It is garbage that is collected and sorted for reuse.

A painting depicting the work of dividing bread on the front porch in Pompeii.

Professor Emmerson said: ' Pompeii live closer to their waste than today's acceptable limits, not because their city lacks infrastructure and they don't care about managing waste management, but because their urban management system has been organized according to different principles of our approach. This is related to the garbage crisis in modern day today. The most effective waste management countries have adopted an ancient model, prioritizing the classification of waste for reuse rather than simply dumping waste. "

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