Salvaging MV Rena – oil removed and first container also taken off !

Dear (s)

In Economics, boom is a flourish or rapid increase of production or sales.  It is a phase of increased activity.  In crane, it is the truss or telescopic boom mounted on a platform.   Have you heard of a containment boom  ?  I had earlier posted about the action in  Astrolabe Reef  near Motiti Island, off the Bay of Plenty coast in New Zealand.  It was the agrounding of MV Rena on 5^th October 2011.  The vessel involved was a a Cargo ship  of 235M length with Liberia flag.  Its IMO No. was 8806802 with call sign  A8XJ7

Now after more than a month of agrounding, there are reports of the first container being lifted off the deck of the stricken cargo vessel.  There are reports that  Salvors have managed to unlock three containers and have taken one off the ship using a crane barge.  It did not contain any cargo (perhaps all the contents been spilled already) – some more are likely to be taken out today.   The good news for all those involved is that almost  all of the oil onboard the ship has been taken off, and efforts are now being focussed on taking the 1280 containers onboard the ship back to shore.  The crane barge Sea Tow was taken out to the site earlier this week but north-easterly swells yesterday prevented salvors from using the equipment.  Though it would still a long way to, the taking away of the first container heralds the logical conclusion of salvage and tow to safety.  

the oil spill

Unlike ground operations in a Port, the removal process would be slow and each container will have to be lifted separately.  Their position, the ship’s position and the extent of damage to the container would all pose vagaries in the act.  NZ Press reports that after many days, beach access restrictions were officially lifted between Mt Maunganui and Maketu Estuary  and somel sections of the beach would remain closed for further cleaning of oil from the vessel.  For stopping spillage from reaching farther points, containment boom had been used.   A containment boom is a "temporary floating barrier used to contain an oil spill. Booms are used to reduce the possibility of polluting shorelines and other resources, and to help make recovery easier. Booms help to concentrate oil in thicker surface layers so that skimmers, vacuums, or other collection methods can be used more effectively. They come in many shapes and sizes, with various levels of effectiveness in different types of water conditions.  There exists various methods like containment booming, diversion booming, deflection  booming.

the containment boom

Spearheading the salvage operations is the crane barge -  Sea Tow 60 (ST60) which was moored at the stern of the grounded ship Rena.  Not sure how it would happen at sea, but in all probability men in cage would go near the containers before using the equipment for removal.  As the vessel is still in unstable condition, there remains apprehensions on the possibility of the vessel breaking up  before offloading of all containers.  Earlier salvage teams had pumped out all the oil after reports of its leaking nearly 350 tonnes killing hundreds of sea birds.

The Mayor of the city of Tauranga,  was quoted as sayting that the  result was tremendous  and that the salvors have done an amazing job under treacherous conditions to avoid an environmental disaster.  The ship's Philippine captain and second officer have been charged over the incident.   The 19 Filipino crew members had been released and had left the country after recording of their statements.   

the salvage operations (courtesy : Maritime Newzealand)

After days of frustrating setbacks for salvors working with oil submerged on the ruined cargo ship,  Maritime New Zealand (MNZ)  reported that about 31 tonnes of oil had been transferred to the tanker Awanuia. There were at least 358 tonnes of oil in the starboard tank.  The biggest challenge had been the submerged No. 5 starboard tank, which divers had to investigate, then seal off, before pumping could begin. Using a method known as "hot tapping", the salvors pumped sea water into the tank to push the oil to the top.   Around 80 containers  had fallen  into the sea during heavy weather some weeks ago, with around half of those washing up nearby.  Contractors used a helicopter to remove 51 cubic metres of debris from the containers from Motiti Island yesterday.

The agrounding of vessel has provided tough time for the ship owners, charterers, cargo owners, environmentalists,  more especially to Maritime New Zealand, the agency in charge of salvage operations.  Though an end is in sight, not all is over and there are valuable lessons to be learnt for all.

With regards

S. Sampathkumar