‘Difficult and dangerous’ procedure to remove oil from stranded cargo ship
November 07 (AAP) – New Zealand salvage experts are pumping seawater into the Rena’s hard-to-reach tank in a difficult and dangerous technique to finally rid the stricken ship of oil. The estimated 358 tonnes of heavy fuel oil remaining in the ship’s submerged starboard tank will be pumped out through three tonnes of hoses laid in place over the weekend. But to access it, salvors are having to pump in 750 tonnes of seawater to lift the oil level higher. Called “hot-tapping”, the technique is a well-established strategy for coping with oil recovery, but is considered both difficult and dangerous, a Maritime New Zealand spokeswoman told NZ Newswire. A further 22 tonnes of lubricating engine oil is also being pumped off in a separate operation, and both are progressing well in fine weather, she said. The wrecked cargo ship has now been grounded on Astrolabe Reef off Tauranga for more than a month. Over that time, about 350 tonnes of heavy fuel oil has leaked into the sea, killing hundreds of birds and washing up on Bay of Plenty beaches. Aerial flights indicate there has been no spill from the boat from several days, with a “very slight sheen” on the water around vessel, but authorities are still on alert for more seepage. “There’s less oil on board the ship but we are still fully prepared to deal with another release of oil from the ship,” the spokeswoman said. Meanwhile, a crane barge has arrived from Australia for removing containers. Authorities stressed the removal was a “second priority” and would not start until all oil was removed. Eighty-eight containers have been lost overboard since the October 5 grounding, with sonar scans finding 32, many on the seabed within 1km of the ship. More than 50 are still unaccounted for.
