US expert says China's worst oil spill is far larger than government has reported so far.

China's worst known oil spill is dozens of times larger than the government has reported, and some of the oil was spilled deliberately to avoid an even larger disaster, an American expert said Friday.

China's government has said 1,500 tons of oil spilled after a pipeline exploded two weeks ago near the northeastern city of Dalian, sending 100-foot- (30-meter-) high flames raging near one of the country's key strategic oil reserves. It has not updated that estimate since a few days after the spill.

But Rick Steiner, a former University of Alaska marine conservation specialist, estimated 60,000 tons to 90,000 tons of oil actually spilled into the Yellow Sea.

"It's enormous. That's at least as large as the official estimate of the Exxon Valdez disaster" in Alaska, he told The Associated Press.

The estimates, though rough, could complicate official efforts to move on and declare China's latest environmental disaster a closed issue: State media has reported Dalian's mayor already declared a "decisive victory" in the oil spill cleanup.

The spill has caused at least one death when a cleanup worker drowned in the sticky crude, and thousands of Dalian residents have used everything from their bare hands to chopsticks to pick the goo from the sea.

Steiner, who worked on the 1989 Exxon Valdez spill, announced the China estimates after touring the oil spill area as a consultant for the environmental group Greenpeace China.

"It's habitual for governments to understate oil spills," Steiner told a press conference. "But the severity of the discrepancy is unusual here."

An official with Dalian's propaganda department told The Associated Press he was not aware of Steiner's estimates and had no comment.

"I think we should follow the figures released by the city government," said the man, who gave his surname as Li.

The government has said the pipeline exploded July 16 after workers continued to inject an agent to strip sulfur from oil after a tanker had finished unloading its cargo.

Firefighters at the scene later told Greenpeace China workers had let oil escape from other nearby tanks to reduce the risk that another nearby tank containing the chemical dimethylbenzene would explode as well.

Steiner said his estimates came from the fact the oil storage tank that was destroyed had a capacity of about 90,000 tons and reportedly had just been filled by the tanker.

He said his lower estimate of 60,000 tons came from the rate of oil recovery by thousands of fishing boats dispatched for the cleanup.

"They've already collected more oil than the official estimate of the spill size," he told The Associated Press.

He praised the makeshift cleanup efforts but said this year's shellfish harvest has been wiped out. Some Chinese environmental experts have said the oil spill's effects around Dalian, once named China's most livable city, will be felt for years.

Both Steiner and Greenpeace China warned their oil spill estimates could be 50 percent off because of the lack of information about the spill and expressed their frustration, putting "information transparency" at the top of their list of demands Friday.

"(The oil) could have spread to North Korea by now. As far as we know, nobody knows," Steiner told the press conference.

Source: AP News