Harwell was established in 1946 as Britain's first Atomic Energy Research Establishment. The site accommodated five research reactors of various types. Harwell also had a number of other nuclear research facilities, together with plutonium handling facilities, radioactive laboratories, nuclear waste treatment and storage facilities.
Decommissioning at Harwell is well underway two of the reactors have been completely removed, and the fuel has been removed from the remaining three which are now in decommissioning. More than 100 other facilities have been removed from the site and others are being decommissioned. Historic wastes are being retrieved from their existing storage locations and repackaged for longer-term storage - and eventual disposal. It is expected that decommissioning will be completed by 2025.