In the 1960s, as a result of the rise of mass production and growing consumption that led to a steep incline in waste generation, landfills were popping up everywhere. Starting in the 1970s however, public attitude towards waste started to change as people became more sensitive to the negative environmental externalities caused by landfilling and the valuable space it occupies. In combination with the emergence of what is nowadays called the Not In My Back Yard (NIMBY) syndrome, policy makers imposed restrictions on the expansion of landfills which caused the remaining landfill capacity to be regarded as a non-renewable, scarce resource.
A possible solution for mitigating the scarcity issue of landfill capacity are so-called Enhanced Waste Management (EWM) practices. The EWM concept consists of two pillars, of which the first one focuses on future incoming waste streams and the second one refers to the excavation and valorisation of historic landfilled waste streams. Having the objective of identifying sustainable waste management practices for the future, research carried out within the Centre for Environmental Sciences of Hasselt University on this topic focuses on the first pillar.
In practice, it may be difficult to find a perfect balance between imposing landfill taxes and defining appropriate taxation levels on the one hand and applying EWM practices on the other. After all, as landfill taxes have the effect of mitigating the scarcity issue of landfill capacity by reducing landfilled waste volumes, less material is made available for valorisation and the application of EWM practices also becomes less essential from a capacity point of view. This has the effect that no extra incentive is given for valorising future incoming waste streams. Similar reasoning can be applied the other way around. As EWM practices substantially reduce the volumes of permanently landfilled waste, remaining free capacity will be practically inexhaustible. This has the effect that landfill taxes are made redundant from a depletion postponing point of view. Only their use in terms of internalising external effects as a Pigovian tax remains in that case partially valid.
By developing and applying economic optimisation modelling techniques, research within the Centre for Environmental Sciences analyses how landfill taxation and EWM can reinforce each other in practice and how taxation schemes can be adjusted in order to foster sustainable and welfare maximising ways of processing future waste streams. Doing this, the research provides generally applicable and policy relevant insights about how to develop and bring into practice sustainable waste management practices and ensure that the concept of the circular economy is put into practice by triggering a resource-efficient economy.