Resumption of drilling work on the Saint-Brieuc offshore wind farm

The jack up vessel AEOLUS left the port of Rotterdam in the Netherlands on July 14 and will be back in the Saint-Brieuc offshore wind farm installation area from July 16. The AEOLUS will take over the drilling and installation of jacket foundation piles. This work had been suspended since June 14 following an incident during the second series of drilling. The electronic safety system of the jig serving as a guide for the drilling had detected a sudden leak of biodegradable hydraulic fluid of the “PANOLIN HLP SYNTH” type, having a low impact on the environment. The work was then immediately suspended and Ailes Marines had actively collaborated with the maritime authorities for the management of the operations.

After the incident, the AEOLUS returned to its home port in the Netherlands. Van Oord's technical teams carried out a complete check of the vessel and its tools. All tools, including the jig, have been thoroughly checked. These reviews made it possible to make changes to significantly improve their performance. The measures implemented were tested by Van Oord during two tests in early July, one on land and the other at sea, in the port of Rotterdam. Both tests have given complete satisfaction.

At the same time, Ailes Marines has decided to re-evaluate all the environmental incident alert thresholds for drilling work upwards.
The work control and monitoring protocols have also been strengthened, by the permanent presence on site of the TSM Penzer vessel, which will be equipped with additional anti-pollution means (SOPEP equipment). The deployment of this equipment was tested during specific exercises in the Netherlands and Cherbourg, on July 13 in the presence of representatives of Ceppol (Antipollution Practical Expertise Center dependent on the Ministry of Defense). Other exercises will take place in the bay of Saint-Brieuc in the coming weeks.

The technical improvements made to the tools, the strengthening of protocols and additional equipment are described in a file submitted by Ailes Marines to the State services on July 9. They guarantee an optimal resumption of drilling work.

In addition, on 21 June, Ailes Marines signed an agreement with the CEDRE (Centre of Documentation, Research and Experimentation on Accidental Water Pollution). This agreement provides a framework for the prevention aspects of pollution response (strengthening of procedures, planning, exercises). It also provides for close cooperation in the event of an intervention and provides for the training of the personnel involved.

It is important to remember that the tools developed by Van Oord for drilling operations use hydraulic systems operating with a biodegradable fluid specially designed and developed for work at sea and produced by the company PANOLIN. This product – related to the leak of June 14 – is classified in the category of "readily biodegradable fluids" according to the international criteria of OECD 301 B, with a very low impact on the environment.