Oil spills a threat to marine biodiversity

PUBLISHED : Saturday, 02 July, 2011, 12:00am
UPDATED : Saturday, 02 July, 2011, 12:00am


Two oil spill accidents struck production platforms in China's biggest offshore oilfield, at the mouth of Bohai Bay , within days last month, causing unknown environmental damage and prompting a massive clean-up campaign, a government official said yesterday.

The official from the environmental protection department at the State Oceanic Administration's North China Sea Branch said the first spill occurred after an accident on the B platform of the Peng Lai 19-3 field on June 4.

A few days later, another accident hit platform C, nearby. This doubled the scale of the spill and complicated clean-up efforts, she said.

The official said the two accidents were not related. The cause of the accident on platform B had been determined, but the situation on C required more investigation.

The clean-up campaign was continuing, but the spill had stopped spreading, she said. No one was killed or injured in the accidents.

The authorities were assessing the extent of environmental damage using helicopters and sea planes, to monitor the spill. 'From what we have seen from the air, the spill area is very big,' she said.

The Southern Weekly reported on Thursday that an oil slick three kilometres long and 20 to 30 metres wide was found floating near the field in early June.

Several industry sources confirmed the spill had been largely cleaned up, with production barely affected, Reuters reported.

The administration would hold a press conference in Beijing on Tuesday, to release details of the scale of the leaks, what caused the accidents, the size of the area affected and the short-term environmental impact, the official said. The Peng Lai 19-3 oilfield is operated by US energy company ConocoPhillips in a joint venture with the China National Offshore Oil Corporation. Production began in 2002 and hit 33 million barrels a day by 2009, according to ConocoPhillips' website.

CNOOC said that an oil leak near the Peng Lai 19-3 oilfield 'has been largely cleaned up', Xinhua reported. It said the leak was discovered early last month, and the cause of the leak was still being investigated.

A spokesman for ConocoPhillips said also 'the source of the slick has been contained and clean-up work is close to completion' and there had been 'no reports of impact to wildlife, fishing, or shipping activities'.

However, Professor Zhao Xuelei , a marine environment researcher with the administration's First Institute of Oceanography, based in Qingdao , said the spill occurred in an ecologically sensitive part of the Bohai Sea and he was worried environmental damage would be far-reaching and prolonged.

The oil rigs involved were operating near Changdao, a county consisting of a string of islands to the north of Yantai with a degree of biodiversity rarely to be found in the Bohai Sea, Zhao said.

The county's economy relied on fishing, aquaculture and tourism. With water quality higher than elsewhere in Bohai, Changdao was home to a number of fish species such as black bream and sea bass. The county also had some of the region's largest aquaculture farms and its most popular beaches.

Sea currents in the region were rapid and capable of carrying pollutants as far as Tianjin .

Zhao said the pollutants included oil and the chemicals used to control the spill. Two chemicals were commonly used during a spill accident - gelling agents and dissolving agents. The gelling agent took the oil to the bottom of the sea, while high doses of the dissolving agent could kill fish instantly. 'Some effects could be seen soon. But most damage will take a long time to surface,' Zhao said.

Greenpeace campaigner Li Yan accused the government of a lack of transparency in its handling of the accident. 'The government should learn from the oil spill in Dalian last year, giving the public timely, detailed and comprehensive information about the incident's environmental impact,' she said.