NEC4 selected for €2bn medical isotopes reactor in Netherlands

NEC4 selected for €2bn medical isotopes reactor in Netherlands

NEC contracts will be used to deliver a state-of-the-art plant for research and production of medical isotopes in the Netherlands. The new Pallas medical isotopes reactor and associated buildings at Petten in North Holland are estimated to cost €1.7–2.3 billion.

The new facility will replace the existing 1961 High Flux Reactor at Petten. This currently supplies some 70% of European and 35% the world’s demand for medical isotopes but is due to reach the end of its working life by 2030.

Dutch client NRG Pallas appointed Argentinian-Dutch designer Ichos in January 2018 and Spanish general contractor FCC Construcción in December 2023 on an Early Contractor Involvement basis. The Dutch Ministry of Health, Welfare and Sport, which is acting as financier and future shareholder, has appointed Mott MacDonald as its technical advisor, including reviewing the proposed procurement and contract strategy and construction of the works.

NEC batch contracts 

Working together as a joint delivery organisation, Pallas, Ichos and FCC will start letting batches of work by the end of 2024 under NEC4 Engineering and Construction Contract (ECC) Option C (target contract with activity schedule) to FCC as elements of the project reach sufficient design maturity. 

Preparatory enabling and piling works started under a separate contract in mid-2022. The main NEC-procured works will include constructing a 63 m by 43 m by 21 m tall building to house the 25 MW open-pool uranium-fuelled reactor together with an associated L-shaped logistics building. 

There will also be a four-storey support building providing access and security control systems, a four-storey office building and a secondary cooling system building. The latter will circulate cooling water from the North Holland Canal through the reactor building and discharge it into the North Sea.

The previous largest NEC contract in the Netherlands was the permanent premises for the International Criminal Court in The Hague, which was completed in 2015 under a €147 million NEC3 ECC Option C.

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