Several officials in Dacheng county, North China's Hebei province, have been punished after media reports exposed the state of two sewage pits in the county, local discipline inspection authorities said on Saturday.

Two pools of polluted water, one of 170,000 square meters, the other 30,000 sq m, which were formed by years of digging and the illegal dumping of waste acid in 2013, have contaminated water and soil in the area.

Pictures of the contaminated pools went viral on Tuesday after a report from an environmental organization exposed the pollution.

Similar seriously polluted sewage pits were also found in Jinghai district, Tianjin.

Although the Ministry of Environmental Protection has launched an investigation, sewage pit pollution control is difficult and complicated in reality as it is often hard to identify the dischargers of the pollution and hold them accountable.

The polluting of the sewage pits in Dacheng county was by a local brick making plant and a chemical fertilizer plant, neither of which still exist. The two factories failed to refill the sewage pits and later two local farmers illegally discharged sulfuric acid into the pits.

In international practice, enterprises should continue to take environmental protection responsibility even after they are dissolved, which should be a good example for China's environmental protection legislation.

In addition, an environmental and ecological restoration and compensation system should be established. And there should be specific regulations for local government's pollution control and management, as well.