The slick covers an area of 101 square kilometers (39 square miles), after almost doubling in size from the start of the week, according to figures released Wednesday by the Chinese State Oceanic Administration.
Chinese authorities said there were four separate slicks that had formed after the Panama-registered Sanchi tanker sank Sunday. The largest oil slick is 48 square kilometers (19 square miles), it added.
The Sanchi was carrying 136,000 tons — around one million barrels — of oil from Iran to South Korea when it collided with the Hong Kong-registered CF Crystal freighter in the East China Sea on January 7.
The tanker was carrying condensate, an ultra-refined, highly volatile form of ultra light crude oil used to make products such as jet fuel.
Environmentalists and officials are worried the oil on board and fuel used to power the massive vessel could harm aquatic life for decades.
“The critical thing is to …
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