The Organization’s activities generate both conventional and radioactive waste in quantities that vary yearly, depending on the type of activities performed (long shutdowns, dismantling projects, etc.). CERN is committed to limiting its waste production and to continuously improving its sorting and recycling.
The majority of waste produced is non-hazardous. It mainly consists of metals, worksite waste, inert waste, household waste and wood. The non-radioactive hazardous waste generated at CERN consists of chemicals and their containers, batteries, printer cartridges, light bulbs and any type of material contaminated by hazardous substances.
CERN has a centralised waste management system that oversees all conventional waste collection and transportation, as well as ensuring the traceability of waste leaving the Organization. The overall goal is that waste is managed safely and appropriately and presents no unacceptable risk to either people or the environment. In 2018, about 56% of all non-hazardous waste was recycled and CERN’s main objective is to increase this rate.
CERN household waste is sent to a sorting centre, where the recyclable part is recovered. The remaining household waste is incinerated in the Cheneviers incineration plant, located in the Geneva canton, where the combustion of household waste produces energy (e.g. CADIOM district heating). Please see the graph below for more details about CERN’s conventional waste eliminated in 2018.
Several initiatives to improve CERN’s conventional waste management have been introduced in the past few years. In 2019, an awareness campaign on restaurant and industrial waste was initiated by the Staff Association, in collaboration with the SCE department and the HSE unit. In 2020, the CERN Environmental Protection Steering Board (CEPS) launched a working group for conventional waste management that investigated various waste issues, such as traceability, reduction in the generation of conventional waste and consolidation of temporary storage areas. During the same year, the HSE unit released a new web-based tool, CERES, for centralising, sharing and ensuring total traceability of chemicals on CERN’s sites, as well as improving hazardous waste management practices.
Radioactive waste is an unavoidable by-product of the interaction between particle beams and the materials in the accelerators. Most of the Organization’s radioactive waste is of very low activation. It consists, for example, of metallic components, cables and ventilation filters, and waste from maintenance and upgrade works. The dismantling of installations can also generate activated concrete from CERN’s underground infrastructures.
Radioactive waste management has always been a high priority for CERN and radioactive waste minimisation is applied during the design, operation and decommissioning of CERN’s accelerators and experiments. In this regard, CERN has developed ActiWiz, a software package that optimises the choice of materials during the construction of accelerator components, identifying and selecting the materials least susceptible to radiation.
Reuse and recycling of radioactive material prior to its declaration as waste is encouraged, so far as reasonably and economically feasible. An example of this is the reuse of activated material as shielding in specific irradiation installations (e.g. beam dumps).
Once reuse is no longer possible, activated materials are treated via a specific elimination process, overseen by HSE’s radioactive waste management team. After the waste is received and categorised, it is treated in a dedicated state-of-the-art facility where it is dismantled, sorted, compacted and packaged according to the elimination pathway criteria. Radioactive waste is eliminated through existing pathways in the Host States, in accordance with the tripartite agreement established with France and Switzerland, both optimising its elimination and respecting the principle of fair share between the Host States.
The next article in this series will go into more detail about CERN’s recycling. In the meantime, more information on the elimination pathways for conventional waste can be found on the SCE department’s dedicated webpage and in the CERN Environment Report 2017–2018.
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This article is a part of the series “CERN’s Year of Environmental Awareness”.