Checks showed that rivers around the industrial park had not been polluted, and local authorities were taking measures to stop polluted water inside the park from flowing out, according to Jiangsu's department of ecology and environment.

Water samples collected at 8:40 am showed the water of three rivers inside the park was polluted by volatile organic compounds－chloroform, methylene chloride, dichloroethane and toluene. But no volatile organic compounds were detected in water of the three rivers outside the park, the department said. In the most seriously polluted river, the dichloroethane and methylene chloride concentration was about 2.8 times and 8.4 times higher than the standard, respectively, it said.

One of the waterways, the Guanhe River, flows into the Yellow Sea, and the plant is only a dozen kilometers from the river's estuary. So it's imperative to stop polluted waters inside the park from entering the Guanhe River, according to a release from a special work team dispatched by the Ministry of Ecology and Environment.

The department said earlier that sulfur dioxide and nitrogen oxides in the atmosphere were dispersing and the concentration was dropping. Other pollutants, including benzene, toluene and xylene, were at normal levels.

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