EngTree
Energy — nuclear
Energy — nuclearNuclear (Decommissioning)

Harwell Research Reactors Decommissioning

Harwell, Oxfordshire, UK · Operations 1946-1990s, Decommissioning ongoing · Part of NRS decommissioning budget

The judgement call

Account-gated at launch

Two reactors have been completely removed, and fuel removed from others, demonstrating significant progress in hazard reduction. - The demolition of the reactor complex (including Zephyr) marks a key milestone in the site's transformation. - The site is being redeveloped into a science and innovation campus, showcasing successful repurposing of former nuclear sites.

Key engineering challenges

Decommissioning a complex site with multiple experimental reactors of varying designs. - Managing diverse radioactive waste streams from research activities. - Demolishing reactor buildings and associated facilities while ensuring safety and environmental protection. - Addressing the long-term legacy of pioneering nuclear research.

Project facts

Client / owner
UK Atomic Energy Authority (UKAEA), Nuclear Restoration Services (NRS)
Lead contractor
KDC Veolia (for specific demolition phases)
Lead designers
Project type
decommissioning
Scale
14 experimental reactors originally, two completely removed, fuel removed from three others (e.g., Zephyr fast fission reactor)
Disciplines
nuclear; civil; structural; mechanical; electrical; waste management; remote handling
Standards & frameworks
ONR

Sources: ONR: Harwell (https://www.onr.org.uk/our-work/what-we-regulate/sellafield-decommissioning-fuel-and-waste/sites/harwell) - NRS SSG: Harwell site (https://nrsssg.com/site/harwell/) - New Civil Engineer: Harwell reactor complex demolished by KDC Veolio for NRS (https://www.newcivilengineer.com/latest/harwell-reactor-complex-demolished-by-kdc-veolio-for-nrs-06-08-2025/) - UK Radioactive Waste & Materials Inventory: Harwell (https://ukinventory.nda.gov.uk/site/harwell/) - Harwell Campus: History (https://www.harwellcampus.com/history/)