Extradós is GDES’s largest execution contract in the French nuclear market

EDF, which owns all nuclear power generation plants in France, began the Extradós project in order to provide a solution to airtightness problems detected in several nuclear power plants in the country.

Some French nuclear power plants are characterised by a design of the reactor contention building that comprises a double concrete wall with a space between the walls of approximately 1.80m without a metal liner. Due to this design, the contention system has shown some airtightness problems in the concrete, with micro-cracks appearing that over time might lead to air leaks during the building airtightness tests in some power plants.

In order to solve these problems, which is critical for the operational continuity of said power plants, EDF designed a system to eliminate or minimise these leaks by improving airtightness based on a fibreglass reinforced coating on the outer face of the first wall of the contention building in the inter-wall area. In turn, EDF sought alternatives to this new system that might lead to significant improvements, as well as different options in the event that their initial plan did not work.

Leveraging its experience, commitment and innovative spirit, GDES studied the project in depth and designed an alternative solution for EDF developed by the GDES unit specialising in coatings, GDES Revanti, in partnership with the subsidiary GDES France.

The system consists in a coating formed by surface preparation using abrasive blasting with metallic particles (aluminium oxide) covered with sponge to minimise dust dispersion, plus two coats of mortar, another two coats of resin laminate with carbon fibre and one final coat of resin finish.

Once the system was approved, EDF awarded GDES a 4-year execution contract to be performed in four stages divided into four actions at the Cattenom 3 and Flamanville 1 and 2 (France) power plants.

The first stage of the project has been successfully completed, and the second stage of Extradós will begin in April 2018. This will involve the participation of 180 workers expressly trained by GDS for the operation. They will work on a surface area of 4100 m² over a period of 3 1/2 months.

Once again, the experience of GDES and its commitment to innovation has made it possible to position the Group as a leading company in the surface treatment industry in the European nuclear market.

GDES’s commercial activity in France began in 2007 and it was consolidated as one of the group’s leading international priorities in 2016 with the formation of the nuclear-industrial division GDES Erba through a strategic alliance with the French company Erba, a specialist in industrial paints and anticorrosion coatings.

GDES has spent several years on gaining a share of the French market. GDES France is currently focused on chemical cleaning, surface treatment, dismantling, waste management and technological engineering projects for the nuclear industry.

GD Energy Services (GDES) is also the only Spanish company that holds the CAEAR authorization to work for the French CEA (Alternative Energies and Atomic Energy Commission) and the second non-French company to obtain this authorisation. This is an exceptional situation which will allow GDES to open a new market in France focused on dismantling, radiological protection, waste management and engineering.