Sinopec Guangzhou, which operates a refinery petrochemical complex that can process 13.2 million tons of crude a year and produce 220,000 tons of ethylene a year, was found to have stored a large amount of an unidentified liquid in two of its emergency tanks.
"The tanks could cause severe environmental pollution in the event of an accident," Zhou said.
Sinopec's Dongxing petrochemical company in Zhanjiang, of western Guangdong, was found illegally discharging sewage through its rain drainage system.
The Dongxing plant, which was originally a Sino-foreign joint venture founded in 1992, was officially taken over by Sinopec in 2002.
The environmental protection authority of Guangdong ordered it to suspend its production in May. However, it later resumed production without permission, Zhou said.
Another subsidiary, the New Sino-US Chemical, a polystyrene producer with a capacity of 100,000 tons a year in Zhanjiang, was accused of illegally dismantling its sewer system and diluting the waste before discharging it into rain tunnels.
The Ministry of Environmental Protection has reported 26 pollution cases in the first half of this year, with nine of them related to Sinopec or its subsidiaries, according to China Central Television.
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