In an oil depot, after unloading a ship, the security agent observed a leak under a fuel pipe connecting the wharf to the depot. The agent installed a recipient to collect the drips and informed the operations manager who in turn informed the head of the depot. Less than 5 litres of fuel had leaked to the ground. The head of the depot observed the leak and decided to install a water pipeline. He informed his superiors and the inspection authorities for classified facilities who visited the site the following day and observed several areas showing significant corrosion especially near each of the supports along the pipeline. Since the pressure in the pipeline was low during the leak, there was no significant impact on the ground.

The initial coating of the pipe was not adapted to the corrosive nature of the marine environment, temperature, high relative humidity, friction and drippings from the mooring ropes of ships. Moreover, according to the operator, the maintenance schedule of pipes was drafted following the recommendations of a specialised body that carried out thickness inspections in 2007 and that stated that the anomalies on account of corrosion were acceptable given the operating conditions of 10 bar. The facility overhaul procedure was underway but the leak occurred before the action plan could be fully implemented. On 19/06/08, the pipeline was inspected by a company expert whose observations contributed to defining the operating conditions in degraded mode for all forthcoming unloading operations. The three other pipelines connecting the depot to the wharf were inspected a few days later (thickness measurement at areas showing external and internal corrosion detected during the 2007 inspection by the specialised body). An operations schedule was drafted based on these measurements: repair of pipelines and supports, installation of collars in sensitive areas, resistance tests, replacement of sections, application of bituminous coating, application of a coating using basic metal deposits obtained by welding, specific protection under mooring ropes, excavation of soil under the pipes running along the banks, etc. The operator decided to reduce the pressure in the pipeline in question to maximum 3 bar and reinforce surveillance until the operating conditions were back to normal. The operating procedures were accordingly modified.