Work ships use an oil-absorbing cable to clean up the oil spill near Platform C at Penglai 19-3 oil field in Bohai Bay, July 12, 2011. According to the State Oceanic Administration, as of July 4, the oil spills had polluted an area of more than 840 square kilometers in Bohai Bay, degrading the water quality from Level 1 to Level 4. [Xinhua]