Work at Saint-Brieuc OWF Halted After Another Drilling Equipment Problem

Van Oord has stopped the ongoing drilling activities its vessel Aeolus is performing at the site of the French Saint-Brieuc offshore wind farm after one of the vessel’s three drills encountered a technical problem.

After less that two weeks of the vessel’s return to the Saint-Brieuc project site, which Aeolus had left last month following a drilling equipment problem, the team on board the vessel encountered another issue with one of the drills during drilling work that was underway on position SB57 within the wind farm site.

The latest drilling equipment glitch occurred yesterday morning (28 July), after which Van Oord stopped all drilling activities and decided to raise the drill. When the tool was raised, hydraulic fluid (which is classed as ‘readily biodegradable’) was found to have leaked onto the vessel’s deck and in the marine environment.

According to the developer of the offshore wind project, Ailes Marines, the Captain of Aeolus reported this immediately to the CROSS Corsen (Regional Operational Center for Surveillance and Rescue) and the maritime coordination centre of Ailes Marines.

In response, Ailes Marines applied the new environmental safety protocols and tools, which the developer and the relevant authorities agreed upon after the last drilling equipment failure and the hydraulic fluid leak – and before the vessel returned to the offshore construction site.

Following this incident, three surveillance vessels were deployed in the area to look for traces of the fluid on the surface, take samples of the seawater near Aeolus, and to intervene near the installation vessel, if needed.

Furthermore, as part of the agreement Ailes Marines signed with CEDRE (Centre of Documentation, Research and Experimentation on Accidental Water Pollution) last month, CEDRE provided the developer’s technical teams with the modeling of the incident and the map of the areas to focus on from both air and sea.

Ailes Marines says it conducted two helicopter overflights of the area and the crews did not notice any iridescence or the formation of slicks in the marine environment. The maritime authorities also carried out a control overflight of the area.

The nautical and air resources Ailes Marines mobilised will continue their surveillance mission for several days in collaboration with the maritime authorities, the developer said.

The company also said it would soon communicate on the results of the ongoing technical analyses.