Dismantling of Zorita containment dome begins

01 November 2019

Spanish decommissioning and waste management firm Enresa has begun work to dismantle the dome of the containment building of the José Cabrera nuclear power plant. The plant - also known as Zorita - is the first to be decommissioned in Spain.

The first section of the containment dome at Zorita is removed (Image: Enresa)

Enresa announced yesterday that the first section of the containment dome - measuring 8 metres in diameter, 16 millimetres thick and weighing 5.2 tonnes - had been cut and removed. Two large cranes were used to manoeuvre the piece from the top of the containment building to the ground.

The company said that dismantling of the plant - Spain's first nuclear power plant - had now reached "an execution progress of close to 89%".

The single-loop pressurised water reactor at the José Cabrera nuclear power plant, in the central municipality of Guadalajara, operated from 1968 until 2006 when it was closed by ministerial order. Although small by today's standards at 142 MWe, the plant nevertheless supplied more than 75% of Guadalajara's power requirements.

Pre-dismantling activities - carried out between 2006 and 2009 under the responsibility of the facility's operator, Union Fenosa - consisted mainly of the management of used fuel and the conditioning of operational waste.

After the completion of pre-dismantling activities and the corresponding ministerial authorisation of 11 February 2010, ownership of the José Cabrera nuclear power plant was transferred to Enresa for decommissioning.

In 2010 Westinghouse - which originally supplied the reactor - won a contract from Enresa to dismantle the reactor vessel internals. This was followed by another contract in 2013 to dismantle the reactor pressure vessel.

The underwater segmentation of the reactor internals and the reactor vessel has been one of the most complex activities carried out, according to Enresa. These operations have been undertaken in the former used fuel pool, using remotely operated cutting tools.

It is estimated that about 104,000 tonnes of materials will be managed throughout the duration of the José Cabrera nuclear power plant dismantling project. Approximately 4% of them will be classified as radioactive waste. Conventional materials are removed and sent to the relevant specific processing plants. Similarly, very-low-, low- and intermediate-level waste is periodically sent to the disposal facility at El Cabril.

Enresa said it maintains collaboration agreements with organisations from several countries - including South Korea, Switzerland, France and Sweden - which provides it with advice for dismantling nuclear facilities.

Researched and written by World Nuclear News