'Who is going to read this?'

Daniela Perenyi is crouched next to a lone waste bin in the hallway of the Kamerlingh Onnes Gebouw (KOG). The words beneath the orange lid are small and set at mid-thigh height – hence the crouching. It seems that this particular bin is labelled for plastic and drink cartons, concludes Perenyi, a master’s student in Clinical Neuropsychology and Project Officer for the Leiden University Green Office (LUGO).

At the restaurant in the KOG, the waste bin situation is slightly better. Three sleek bins stand together as one unit. They are colour coded in a way that should be familiar to anyone who has been around the university in the past: orange for plastic and drink cartons, green for organic waste, and grey for residual waste. The bins include both words and a picture to help people sort their waste. Perenyi is pleased with the options and the colour coding but would like more explanation, noting that the difference between the orange and grey bins is still unclear.

In the past, waste bins signs were full of words. Now, most restaurants at the university have shifted to a more minimalistic approach. Bins matching those in the KOG restaurant also sit in restaurants at the Gorlaeus Lecture Hall, Van Steenis, Lipsius, and Pieter de la Court buildings. One outlier is the Snellius building restaurant. While all three bins are present, the green and orange bins are covered. This gives diners no choice but to toss everything into the remaining grey residual waste bin.

'I just don’t get why they have so many separate bins,' Perenyi sighs as she points out a pair of small square bins and then an unlabelled basket next to a copy machine. Further on, grey residual waste and orange plastic and drink packaging bins dot the hallways in seemingly random configurations. After walking by a group of students eating lunch in a tucked away booth in the hallway, Perenyi peers into a grey bin. 'People eat in places other than canteens,' she notes. 'This grey bin is full of banana peels and organics. This could be separated.' But with no green waste bin in sight, it’s hardly surprising that organics end up tossed in with residual waste.

The variation in labelling and placement of waste bins is not unique to the KOG. Other university buildings are also dotted with grey residual waste and orange drink and plastic packaging bins. Often, these bins do not sit next to one another. Further complicating matters are buildings such as the Gorlaeus, which have unlabelled metal bins in addition to the labelled grey and orange bins. It’s unclear what is supposed to go into the unlabelled bins.

Confusing

Placement and labelling of waste bins throughout the university has implications for waste sorting. Last year, LUGO, a platform for promoting and integrating sustainability at the university, was involved with a sample test of waste at the Humanities Faculty. They found 'quite a bit of waste in the general waste bin that should be recycled in a different bin.'

It’s easy to see how waste sorting could be confusing. Perenyi counts at least four differently shaped and labelled bins for various types of waste while walking through the KOG. Unification of bin placement across faculties and clear instructions for how to sort waste could help students and staff better separate their waste.

Green energy

With all this sorting, where does the waste end up? The university website details how waste from each of the bins is processed. Plastics are used to make new bottles or as raw materials for construction. Organic waste is mostly used to create green electricity. Residual waste – similar to a ‘none of the above’ option on a multiple-choice exam – is the least environmentally friendly. It is burned to create energy. 

When approached by Mare, university cleaning staff confirmed that waste from the different bins is treated differently. It is collected from bins throughout each building and sorted into separate colour-coded containers before being picked up by waste management company Renewi or another specialised company. This marks an improvement from the previous situation. In 2018, Mare reported that despite the presence of colour-coded bins, the contents of the orange bins – then referred to as PMD – were placed on ‘one big pile’ along with grey bin residual waste. 

Given the extensive sorting of waste, it seems reasonable to assume the university would want to measure the different types of waste. Yet the Leiden University Annual Report from 2023 and the Sustainability Report from 2022 include only two categories for waste measurement: general waste, and paper and carton. Waste from the orange and green bins is absent from the reports. According to University Spokesperson Mischa van Vlier, the university is working to change this. Starting in 2024, the annual Sustainability Report will include additional waste categories, although van Vlier did not specify which categories would be added.

In addition to improving waste tracking, the university also aims to decrease waste per user by 25% between 2019 and 2027. 'Even better than separating waste, is not generating it at all,' says van Vlier. Efforts at waste reduction take many forms. For example, in 2022 LUGO helped with a pilot test that switched disposable coffee cups for reusable Billie cups at the Law Faculty.

In 2023 this change was implemented university wide. Currently all hot beverage machines at the university require a reusable cup. Since then, an estimated 20,000 to 25,000 kilograms of paper cups have been saved, weighing the equivalent of approximately 18 cars. Designated bins for paper towels were also installed in the toilets, allowing used paper towels to be recycled into new paper towels.

The use of colour-coded bins and efforts to reduce waste are positive steps towards creating a sustainable university. But students at LUGO, Perenyi included, feel there is also a need for better communication. When asked what she would like to see changed about waste management at the university, Perenyi says, 'more visibility for what type of waste goes where.'