China is cracking down on environmental crimes. The latest such effort is that a court there has fined DyStar $3 million and sent some of its managers to jail. DyStar is a dye producer that is specifically accused of dumping illegal industrial waste in local rivers.

According to the Ministry of Environmental Protection, 28% of rivers and lakes in China were “unfit for human contact” in 2015, as reported in Chemical and Engineering News.

According to the story, the incident was first captured in May 2014. That’s when authorities boarded a ship that is alleged to have disposed of the hazardous waste and to have smelled the same chemicals that it found in the river system there. Over four years, the company dumped more than 3,000 metric tons of hazardous waste into local waterways, the story says.

“Management has neither authorized nor tolerated the illegal disposal of waste material at any time,” the company told Chemical & Engineering News.