In this photo taken on Wednesday, July 21, 2010, released by Greenpeace, mollusks are seen coated in crude oil, at the Guotai Water Products Farm, less than a mile away from the site of an oil spill, at Xingang Port in Dalian in northeast China's Liaoning province. China National Petroleum Corp. said Thursday the vital pipeline has resumed operations after an explosion caused the country's largest reported oil spill. Cleanup efforts, marred by the drowning death of a worker, continued over 165 square mile stretch of water blanketed in thick, dark oil Thursday, after an official warned the spill posed a severe threat to sea life and water quality. (AP Photo/Greenpeace, Jiang He)

Photo by: Jiang He

In this photo taken on Wednesday, July 21, 2010, released by Greenpeace, mollusks are seen coated in crude oil, at the Guotai Water Products Farm, less than a mile away from the site of an oil spill, at Xingang Port in Dalian in northeast China's Liaoning province. China National Petroleum Corp. said Thursday the vital pipeline has resumed operations after an explosion caused the country's largest reported oil spill. Cleanup efforts, marred by the drowning death of a worker, continued over 165 square mile stretch of water blanketed in thick, dark oil Thursday, after an official warned the spill posed a severe threat to sea life and water quality. (AP Photo/Greenpeace, Jiang He)