A mid-January spill of toxic cadmium in China's Guangxi region continued to spread today, potentially poisoning the water supply of up to 3.7 million people. The spill infected two major rivers in the region, which have now spread cadmium up to 130 km downstream. As of today contamination was still on the rise despite cleanup efforts; however Chinese officials are claiming to have contained the contamination and halted the spread. Chinese environmental authorities had announced a redoubling of efforts and resources this morning.
The source of the spill is still undetermined but evidence points towards six metal companies and a mine.
The Guangxi Jinhe Mining Co. was reported to be the suspected main cause of the contamination because its waste disposal continually failed to meet government standards despite repeated citations, the newspaper China Business News reported.
According to industry websites, the company, a subsidiary of Guangxi Nonferrous Metals Group, makes zinc ingots and zinc oxide used as white pigment for rubber, cosmetics, medicine, ceramics and glass. Cadmium naturally occurs in zinc ore and is a toxic byproduct of smelting.
The cadmium had polluted a 100 kilometer (60-mile) stretch of the Longjiang River at a level more than five times the official limit of 0.005 milligrams per liter, the official Xinhua News Agency reported Monday.
“It is a critical time right now as downstream drinking water safety is in jeopardy, so we will take every measure possible and optimize our strategies to bring down cadmium concentration levels,” it quoted He Xinxing, Hechi’s mayor, as saying.
Chinese emergency personnel are erecting barrages and pouring hundreds of tonnes of chloride into a river in southern China in a desperate effort to prevent a toxic spill from contaminating the supplies of a major city.
The flow of cadmium - discharged into the Liu River earlier this month - has continued despite three previous containment operations, and now threatens the 3.2 million residents of Liuzhou city in Guangxi province.
Thousands of police, soldiers and fire brigade officers have been mobilised to halt the spill, which has sparked panic buying of bottled water and underscored the environmental cost that China is paying for its rapid economic growth. [...]
The source of the spill is still being investigated, but the possible culprits - six metal companies and a mine - have been temporarily shut down and the authorities say no new toxins are entering the water. [...]
Zhang Jian, the spokesman of the Liuzhou government, told the Guardian the city was able to treat the water safely as long as cadmium levels were within twice the national standard. If that was not possible, he said the government was prepared to tap substantial underground supplies owned by a nearby railway.
Many fish died despite efforts by local fire officials to dissolve the cadmium by pouring hundreds of tonnes of neutralizers into the river, and authorities reported panic buying of bottled water by local residents.
Xinhua said officials blamed the Guangxi Jinhe Mining Co. for the January 15 spill, but it was not clear how long the company had been discharging the chemical into the river or how much had had been released.
As of Friday, elevated levels of cadmium were being detected in Liuzhou, more than 130 km downstream from the plant, according to the report.
Now the New York Times is reporting:
Officials in southern China appear to have averted environmental calamity by halting the spread of a toxic metal that had threatened to foul drinking water for tens of millions of people, the state media reported Monday.
Officials said they had successfully diluted the concentration of cadmium, a poisonous component of batteries, that has been coursing down the Longjiang River in the Guangxi Zhuang Autonomous Region.[...]
According to officials in the city of Liuzhou, workers neutralized the cadmium contamination over the weekend by dumping tons of other chemicals into the river. The chemicals, polyaluminum chloride and sodium hydroxide, are supposed to bind with the cadmium and then settle to the river bottom. City officials said they would later dredge the river sediment.
Despite what appears to have been a disaster avoided, the episode highlighted China’s continuing struggle against contamination of its waterways. The Ministry of Environmental Protection has acknowledged that half the nation’s rivers and lakes are unfit for human contact, and news media reports of chemical and oil spills are commonplace here.