Recent aerial photographs of extensive pollution at industrial sites in northern China have caused a public outcry, and calls for action from the authorities.
The images, taken by a drone, show a cluster of dark red and rust-coloured pits occupying a big patch of land in a village called Nanzhaofu in Hebei province.
The NGO which broke the story, Chongqing Liangjiang Voluntary Service Centre, said preliminary tests it conducted showed the waste water in the pits was strongly acidic.
The pollutants have been been there for years, it said, meaning the underground water might have been contaminated.
The centre said three pits in total had been found, covering a total of 350,000 sq m.
The two largest were 500m apart in Nanzhaofu while a third smaller one was found in Xizhaizhuang county in Tianjin.
Together, the two provinces circle Beijing. Volunteers told Chinese media that similar polluted land could be found in other provinces.
After the images were published on the NGO’s social media accounts last week there was an outburst of public anger.
“Those photos are shocking, the authority has been doing nothing, I am so angry!” one social media user said.
“My aunt is from that county in Hebei, she died from cancer two years ago. Her grandson is suffering from cancer and her mother in law has cancer too,” said another.
“I thought it was just coincidence but now I don’t. The government has to provide us a safe environment.”