On March 28, 2020, in Heilongjiang Province of China, water containing residual molybdenum ore, extracted from the metal used in stainless steel and tools, flowed from a tailings pond belonging to Yichun Luming Mining Co Ltd and entered a river system.
A spill from a tailings dam at a molybdenum mine in northeast China on March 28 has polluted the water up to 110 km downstream, environmental authorities said on April 1. Tailings dams are commonly used by mining companies to store mineral waste, but have been under close scrutiny since the collapse of one in Brazil last year killed more than 250 people.
No reported victims
Water tests in the Hulan River, about 110 km southwest of the Yichun mining site, showed that the molybdenum content was 2.8 times higher than standard levels, the Heilongjiang Department of Ecology and Environment said.
The Hulan flows into the Songhua River, the fifth longest in China, in a northern district of the provincial capital Harbin. The oil content was 1.4 times higher than standard levels at the same location and the chemical oxygen demand (COD), a measure of water quality, was 5.7 times higher.
A high COD reading indicates a greater threat to aquatic life. Molybdenum itself is not toxic. The problem with tailings water is the buoyancy agent: oil, a source in the molybdenum industry said. Buoyancy agents are used to help extract minerals from the ore. Levels were even closer to the site of the spill, readings released by the Heilongjiang environmental department showed.
A report published on the Ministry of Ecology and Environment website said 2.53 million cubic meters of tailings pond discharge had been discharged. The official Xinhua News Agency said the leak was closed on Tuesday, March 31. Yichun Luming Mining, a subsidiary of China’s state railway resources group, did not immediately respond to a request for comment on the production status of its mine. Today, most of the risks from tailings ponds have been brought to the attention of regulatory agencies, said Ada Kong, director of Greenpeace East Asia’s toxic campaign. However, tailings ponds and dams are time bombs due to their large volume, and the challenge for local authorities remains significant.
Breaking: On March 28, a tailings sand #leak occurred in a tailings pond in Yichun, Heilongjiang Province, and partly entered the Yijimi #River. After learning about the situation, the Ministry of Ecology and Environment attached great importance to it and launched an #emergency pic.twitter.com/aMKPW0Ubdq
— CBCGDF (@CBCGDF_China) March 29, 2020
Water containing waste molybdenum ore from a state-run enterprise's subsidiary threatens to contaminate the local water supply. The pollution has triggered an emergency response in Northeast China's Heilongjiang province. pic.twitter.com/vf1tbsr7Sw
— Caixin Global (@caixin) March 30, 2020