OS 35 wreck removal on track despite storm damage
The wreck of the OS 35 was almost ripped in two by recent storms that also damaged a large section of the ship’s accommodation block, but the situation remains stable and the removal operation is still on track to complete by May 30.
The update on the wreck was provided on Tuesday by John Ghio, the Captain of the Port, who had earlier received a detailed assessment from Koole Contractors, the salvage company tasked with the removal operation.
Salvors had planned the possibility of storm damage to the wreck, stripping the accommodation block and emptying the vessel of its fuel cargo to minimise pollution.
The wreck has sunk deeper into the seabed having earlier been flooded to provide increased stability.
While the OS 35 is embedded deeper in the seabed, it has not shifted location and remains upright.
Salvors are conducting a deeper assessment to see if the original plan needs to be tweaked but for now, the timescale remains as envisaged and the aim is to remove the entire wreck before the official bathing season.
“The storm damage is eye catching, but it’s something that we always anticipated and that we had planned for,” Mr Ghio told reporters during a briefing.
While the wreck has sustained structural damage, most visibly to the starboard side of the accommodation block and hull, this is not considered to be extensive given the overall situation.
The debris from the damage is contained within the site of the wreck.
The original crack in the hull has extended to the port side, and the two parts of the ship are now only tenuously held together by the very bottom part of its structure, known as the bilge keel.
The bow is now sitting a further four metres into the sandy seabed, whilst the stern now sits a further two metres into the seabed.
This is a result of shifting sands with heavy swells.
However, the OS 35 has not moved from its original site, demonstrating the effectiveness of the strategy to stabilise the vessel with a controlled sinking, Mr Ghio said.
This provided the wreck with the maximum possible stability to weather the expected winter storms.
FUEL TANK 1
The damage to the hull has enabled divers to conduct visual inspections of fuel tank No.1.
As a result, divers were able to confirm that all four tanks that make up ‘Tank 1’ have suffered damage.
There is still some light sheening being released by the wreck, which is being contained successfully within the boom.
The other set of fuel tanks, No.2 fuel tanks, remain undamaged and are situated in the aft area of the wreck, which has not suffered any hull damage.
The dive survey has confirmed with certainty that these tanks are intact and are not at risk of failing and causing a sudden release of residues.
“These tanks had been emptied in earlier stages of the operation and although it is likely that some residues remain and future light sheening can never be entirely ruled out, the risk of future escapes of oil is now dramatically reduced,” No.6 said in a statement.
WRECK REMOVAL PLANS
The removal of the vessel’s cargo continues to be the first priority at this stage of the operation, with over 11,000 tonnes - representing around a third of the total cargo - already removed.
Between 600 and 900 tonnes of cargo are being removed daily.
The damage caused by the storms has had no detrimental impact on the cargo removal operations or their timelines.
The work to remove the OS 35 and its cargo continues to progress well, and the downtime dictated by the winter storms was built into the planned project timeline.
The current condition of the wreck and the damage to its hull and structure mean that some of the plans for its final removal may need to be tweaked, although it is unclear as to how this may affect the projected timelines, if at all.
One of the issues being assessed is whether a crack on the bow section that was worsened by the storms could impact plans to lift that section onto a barge.
ENVIRONMENTAL IMPACT
As previously reported, small amounts of residual oil were found on Eastern Beach, Catalan Bay and the rocks at Sandy Bay in the aftermath of the storms.
These had been anticipated and quickly dealt with by the P&I Contractors, monitored by the Gibraltar Port Authority and Department for Environment.
Due to the stripping of the accommodation’s interior in anticipation of the storms, no secondary contamination or debris was detected.
STAKEHOLDER BRIEFINGS
The Captain of the Port maintains constant communication with his counterparts in Spain, and on Tuesday briefed Spanish authorities with the latest information.
The Captain of the Port has also briefed other stakeholders, including the residents of Catalan Bay.
“The damage to the vessel’s hull and accommodation block, whilst not ideal, were anticipated and prepared for with the removal of as much oil as possible and the complete stripping of the accommodation,” Mr Ghio said.
“These measures, together with the decision to sink the wreck in a controlled manner and thereby secure it in place, gave the vessel the maximum possible stability to withstand the winter storms as far as possible.”
“Overall, I’m pleased that works continue to progress well, with cargo removal remaining as the current priority.”