China’s top environmental watchdog sharply criticized the country’s largest private steel-maker on June 28 for failing to carry out rectification plans and dumping steel slag along the Yangtze River in Zhangjiagang, Jiangsu province.

According to the environmental inspection team sent by the Ministry of Ecology and Environment, the steelmaker, Shagang Group, has been dumping large amounts of waste from the steelmaking process along the banks of the Yangtze, posing great danger to nearby waters and soil.

The group, while contributing greatly to the local economy, failed to correct problems found in previous rounds of inspections, including large emissions of smoke and dust, the inspection team said in a statement. Shagang Group, which is the largest private metallurgical enterprise in China, has been on the list of the world’s top 500 enterprises since 2009, ranking 365th in 2017. In July 2016, the first round of environmental inspections in Jiangsu found that the group had released gas that did not meet environmental standards. The Zhangjiagang Environmental Protection Bureau fined the group 100,000 yuan ($15,000) and ordered it to correct the problem by the end of 2016.

However, a team dispatched by the Ministry of Ecology and Environment to revisit the site found that the polluting gas emissions continue, and that dust removal facilities were not functioning normally.

Meanwhile, the inspection team found some 2.3 million metric tons of slag placed only about 800 meters from the Yangtze by both Shagang Group and Jiangsu Yonggang Group, another steel giant whose total assets surpass 40 billion yuan.

According to the inspection team, dozens of slag mountains more than 10 meters high are piled along the river and occupy an area of 1.35 square kilometers. In 2015, alkaline runoff from the slag was found to have polluted nearby waters.

The team added that only after Shagang was punished in 2016 did it construct rainwater collection pools to eliminate the risks.

Shagang also simply buried chemical waste at a landfill, and the local government failed to monitor environmental protection work, it said.

In a statement, Shagang Group said it will pay great attention to environmental protection problems and take immediate action to correct the ecological damage.

“The group will invest 2.14 billion yuan to tackle the emission of smoke and dust,” the group said. “The reconstruction of flue gas desulfurization and denitrification facilities will be completed by the end of 2018. At the same time, the amount of slag will be reduced by half.”

It said that all the piled slag will be removed within one year and a third-party organization will be asked to make ecological restoration plans.

Zhangjiagang has hired professional organizations to deal with the landfill. It ordered that garbage be classified and treated specifically based on its composition.

According to Chen Yongze, deputy director of the city’s publicity department, 34 officials and people in charge have been punished for dereliction of duty.

“Four leaders from Shagang have been dismissed from their posts or demoted. A special team has been sent to Shagang and will work with third-party organizations to scrutinize its problems.”

The city’s environmental protection bureau will continue monitoring the group to ensure all the environmental problems have been rectified, he said.