Clean-up operation continues on east side after storm releases oil from OS 35
The clean-up operation on the east side of the Rock continued on Thursday morning after rough weather a day earlier caused further damage to the wreck of the OS 35, releasing residual oil into the sea.
Globules of thick fuel oil washed up on the beaches in Catalan Bay and Sandy Bay and on the rocky shoreline, prompting concern about the impact on the marine environment and animal life.
The OS 35 was carrying 183 tonnes of heavy fuel oil for its own consumption, alongside 250 tonnes of diesel and 27 tonnes of lube oil.
All of those fuels were removed during early stages of the salvage operation but the wreck still contained residual coatings in the fuel tanks and salvors had warned from the outset that further pollution was possible.
A boom used to contain any releases while salvage work is underway was removed earlier this week ahead of rough weather, which would have made it ineffective and risked damaging the equipment.
The residual oil was released after heavy swells shifted the wreck, breaking it further in two and causing the stern section to list heavily while still settled on the seabed.
The additional structural damage allowed the sea to wash out some of the residual oil left on the wreck.
There was still a strong smell of fuel oil on the beaches, though it was not as intense as on Wednesday given that a lot of polluted sand has already been cleaned up by work teams.
Sea conditions are calmer too, facilitating the clean-up operation on the beaches.
Francisco Barranco Jimenez, who was supervising an oil spill response team from Brightside, was part of a team of nine on Catalan Bay, with other teams deployed in Sandy Bay too.
Workers in white overalls used street brooms and pans to lift the oily residues from the beach without removing too much sand, collecting the polluted material in bags for specialist disposal.
Already dozens of bags of contaminated material have been collected.
He said workers would continue with the task "until the beaches are completely clean", adding that teams from other companies including Britannia and GJBS were also ready to assist if needed.
On Thursday morning, the Captain of the Port, John Ghio, updated the OS 35 Recovery Coordination Group on the situation as the coastal clean up progressed.
He confirmed that the wreck’s hull was observed to be shifting Wednesday mid-morning. By 3pm the storm was at its peak, with high tide reaching at 4pm.
This extreme waxing and waning led to the final separation of the bilge keel, which following an earlier storm was the only "very tenuous" remaining connection between the wreck’s two otherwise entirely separate parts.
"It is the working hypothesis that the oil escape was fuel oil trapped in the pipeline that connected fuel tank No.1 with the engine compartment," No.6 Convent Place said in an update.
"The fuel remaining in this pipeline at the time of the vessel’s initial sinking was impossible to recover and the valves to this pipeline were closed off in the initial stages of the recovery operation to secure the pipeline and in order for the fuel to be
pumped out of tank No.1."
"All recoverable oil was removed from the wreck at this stage."
There have been no further reports of oil escape after Wednesday afternoon, confirming that this oil was the unrecoverable fuel from this pipeline.
"However, further escapes of oil cannot be ruled out, as it is impossible to know potential quantities and locations of remaining
trapped oil and residues," No.6 added.
The situation is being constantly monitored by the Gibraltar Port Authority and the Department of Environment.
The heavy weather at sea is expected to continue through until next week and it is unlikely that the boom can be replaced in this time.
Salvage teams will take advantage of any lull in the weather to deploy dive teams to investigate the damage and implement oil mitigation measures as far as possible.
The Department of Environment has advised that Eastern Beach appears to be free of oil, whilst Catalan Bay, Sandy Bay and Little Bay are temporarily closed in order to allow the clean up operation to progress as quickly as possible.
No.6 said the cleaning of the coastline is progressing well, in coordination with the contractors and Oil Spill Response Limited.
The Captain of the Port fully briefed the Spanish authorities yesterday as the situation developed, and both parties continue to work in close coordination.
Earlier on Thursday, a Spanish maritime rescure helicopter overflew the wreck to monitor the oil leak.
The situation will be constantly monitored, with teams working throughout the holidays on monitoring and coastal clean up operations.
People are being asked to avoid the beaches while the clean-up operation is underway.