Archaeologists find worrying amount of plastic waste at Iron Age site

One by one, the archaeologists came across pieces of junk. Using techniques typically reserved for documenting stone tools and bones, the team recorded items such as plastic spoons, glasses, bottle caps, straws, cell phone batteries, lids of paint cans, candy wrappers and plastic wrap. By the end of the experiment, archaeologists had discovered nearly 3,000 objects, the vast majority of which consisted of Plastic.

That plastic was found at the site, an ancient hill in Wales, was no surprise. In fact, it was expected, but not to this degree.

Since the 1980s, two replicas of Iron Age round houses have existed here, matching those that once stood at the Iron Age fort of Castell Henllys at the end of the first millennium BCE.

Most of the visitors to the site were children on a field trip, whose legacy is only now understood. Like New Antiquity paper shows that plastics are used to stick around, including in heritage sites that existed long before the invention of these synthetic materials. This is yet another sign that we have entered the Anthropocene, a period in which we are remaking the planet in our own image.

The replica round houses of Castell Henllys had two different purposes. The first, named Cookhouse, was laid out as a true Iron Age rotunda, while the second, called Earthwatch, was set up as a classroom, where students sit on benches to learn and eat. their snacks.

The Pembrokeshire Coast National Park, which manages the site, recently decided to dismantle the rotors due to health and safety issues. Before building new structures, however, archaeologists deemed it wise to excavate the site. It would be a good opportunity to study the degradation processes, to determine what human activities lead to waste remains and how the replicated structures might affect the integrity of the prehistoric structures located on the same site. Here, the two replicas of roundhouses were literally built in the same location as the real ones that existed over 2000 years ago. As the authors wrote in their study, “We predicted that the assemblages and distributions of artefacts at Castell Henllys could serve as valuable tests to correlate accidental releases with activity patterns.

This turned out to be the case, but the amount of trash seen at the site exceeded their expectations.

“We often find a small amount of recent debris at the start of an excavation, or if we find a deliberate dumping ground, but never like this in a heritage site or occupation building,” Harold Mytum, archaeologist at the University of Liverpool and first author of the new paper, explained in an email.

This does not mean that the heritage site has been poorly managed. The round houses were cleaned regularly to maintain the look and feel of prehistoric Iron Age decor. But as the new research shows, a surprising amount of trash managed to find its way into the ground, leading to the discovery of so many objects. Needless to say, the vast majority of the items recovered were found in Earthwatch, where the students ate their snacks. Most of the items were small and fragmentary in nature, such as torn packages, which is why not all of the garbage was collected.

“Children’s packaging [lunch packs] can damage the planet – they contain a lot of plastic and things fall and get lost, ”Mytum said. “In addition, the candy wrappers are plasticized and pose another environmental threat.”

Needless to say, finding all this plastic, while certainly part of the experience, forced archaeologists to fine-tune their approach. Scientists had recorded all the findings, but they had to adjust their resources “to do justice to the evidence,” Mytum said. That said, this did not affect the ability of archaeologists to examine how buildings had deteriorated over the decades. and to document the distinct signatures left by our modern civilization.

“Indeed, it revealed how the artifacts are incorporated into the flooring and also where they were most dense inside the houses,” Mytum explained. “The prehistoric houses have fewer finds, but we can think of how the activities leave their mark in archeology.”

Going forward, Mytum and his colleagues will continue to work with the Pembrokeshire Coast National Park to educate the public on these issues. and find more efficient ways to keep these important spaces clean.

But it won’t be easy.

“Even well-managed rural locations can have a significant build-up of plastics in the soil,” Mytum said. “The age of plastic – an indicator of the Anthropocene – did indeed come not only from the oceans of the blue planet, but also from its soils. It is essential to reduce the use of plastic – this debris was a byproduct of our way of life, even in a place where all obviously modern materials, such as plastic waste, are disposed of to avoid affecting the heritage visitor experience.

To which he added: “If it’s that bad here, it’s a sign that our way of life needs to be rethought.”