East China Sea oil fire out but eco threat lurks from sunken Iranian tanker
Vessel’s bunker fuel and cargo of light crude could inflict serious damage on marine environment, oil specialist says
The fire from a sunken Iranian tanker ship in the East China Sea has burned out, a Chinese transport ministry spokesman said on Monday, although concerns remain about possible major pollution to the sea bed and surrounding waters.
The spokesman said the fire from the tanker Sanchi stopped around noon. Earlier footage showed huge clouds of thick smoke rising from the oil slick.
Just three bodies from the vessel’s crew of 30 Iranians and two Bangladeshis, have been recovered.
The cause of the January 6 collision between the Sanchi and the Chinese freighter CF Crystal, which happened 257 kilometres (160 miles) east of Shanghai, remains unclear. All 21 crewmembers aboard the freighter were reported safe.
Rescuers boarded the Sanchi on Saturday morning to recover two bodies, but a large explosion shook the ship around noon on Sunday and it sank within hours. High temperatures had prevented rescuers from entering the crew quarters.
The ship was carrying a type of hydrocarbon liquid known as natural gas condensate and left a 10 square kilometre (3.8 square mile) area contaminated with oil, according to Chinese authorities. Condensate is highly toxic but readily evaporates or burns off in a fire. If trapped underwater, however, it could seriously harm the marine environment, while the ship’s fuel source also poses a major threat.
Experts worry the ship’s sinking is potentially more damaging to the marine ecosystem than letting the condensate oil burn off. The sinking will likely expel the remaining condensate and the tanker’s bunker fuel, or the heavy fuel oil that powers a ship’s engines, contaminating the surrounding waters.
Bunker fuel is the dirtiest kind of oil, extremely toxic when spilled, though less explosive. Condensate is poisonous to marine organisms.
A harmful plume of condensate would likely be in the water, out of sight of observers on the surface, said Rick Steiner, a US marine scientist based in Anchorage, Alaska, who has experience of oil spills.
“As with all major oil spills, time is of the essence. This is particularly so with condensate spills, as the substance is so toxic and volatile,” Steiner said.
He said the East China Sea was known for its rich, although already polluted, marine ecosystem, with whales, porpoises, seabirds and fish.
Fuel oil is relatively easy to contain because volumes are lower and its viscosity means it is easier to extract from water, but even small volumes can harm marine life.
A Suezmax tanker can hold a maximum of 5,000 tonnes of bunker fuel. The Sanchi may have been carrying about 1,000 tonnes by the time it hit the grain freighter CF Crystal, according to bunker fuel traders’ estimates.
The ship’s voice data recorder, which functions like a “black box” on aircraft, was reportedly recovered on Saturday, possibly helping shed light on how the collision and resulting fire occurred.
The transport ministry spokesman said new photos and video footage showed the fire had gone out entirely. He said an investigation into the disaster would be conducted according to the “strictest international standards.”
Chinese state broadcaster CCTV said rescue operations had been converted at noon to a search-and-recovery effort. Two ships were on the scene spraying foam detergents to dissolve oil remaining on the surface.
The disaster has transfixed an Iran still reeling from days of protests and unrest that swept the country at the start of the year.
Families of the sailors wept and screamed at the headquarters of the National Iranian Tanker Co in Tehran, the company that owns the Sanchi. Some needed to be taken by ambulance to nearby hospitals as they were so overwhelmed by the news.
State TV earlier quoted Mahmoud Rastad, the chief of Iran’s maritime agency, as saying: “There is no hope of finding survivors among the [missing] 29 members of the crew.”
Iranian President Hassan Rouhani and Supreme Leader Ayatollah Ali Khamenei both expressed their condolences, with Rouhani calling on relevant government agencies to investigate the tragedy and take any necessary legal measures. The government also declared Monday a nationwide day of public mourning over the disaster.
Chinese officials blamed poor weather for complicating their rescue efforts. Thirteen ships, including one from South Korea and two from Japan, had joined in the rescue and clean-up effort.
The Panamanian-flagged tanker has operated under five different names since it was built in 2008, according to the UN-run International Maritime Organisation and the industry website Maritime Traffic.
It is the second collision for a ship from the National Iranian Tanker Co in less than 18 months. In August 2016, one of its tankers collided with a Swiss container ship in the Singapore Strait, damaging both ships but causing no injuries or oil spill.
Additional reporting by Reuters