As an aluminium smelter belches pollution into the hazy brown sky over Huangjiawa, a villager who used to till the land where the smelter now sits recalls a time when things were different. "Ten years ago the water in our rivers was so clean, even cleaner than the piped water is today," says Mr. Zhang, who declined to give his full name.
Today the area has one of the highest rates of stomach cancer in the world, and the wells that sustained the village for centuries have been poisoned.
But unlike other victims of pollution across China, the village of Huangjiawa has shot to national prominence as an online media campaign highlighting its plight has sparked a debate about groundwater contamination that has ricocheted all the way to Beijing. For Xi Jinping, China's new leader who will be named head of state this week, growing public anger over environmental deterioration is set to be a key test of his leadership.
Chinese citizens are increasingly turning online to vent their anger over pollution – and the government has been forced to respond. When record-breaking smog blanketed northeastern China in January, the Chinese public knew about it instantly because of the pollution apps that many have on their smartphones, and the government in Beijing rolled out new anti-pollution measures within days.
The debate over groundwater pollution in Weifang prefecture, where Huangjiawa village is located, was sparked by a short, pointed microblog post earlier this month on Weibo, China's Twitter-like microblog service. It quickly went viral, and recently the issue of water pollution has been raised on primetime television and elicited an admission of the existence of hitherto hushed-up "cancer villages" from the government.
In the initial Weibo post, activist Deng Fei accused aluminium smelters in Weifang of illegally pumping wastewater underground into pressurised wells. The issue struck a chord with Mr. Deng's 3 million followers. More than 70 per cent of China's groundwater is seriously polluted, which scientists say has resulted in higher rates of cancer and other illnesses.
During the lunar new year, dozens of Mr. Deng's followers posted images of the polluted rivers and streams in their hometowns when they returned home for the holidays.
"With Weibo, any person can be a reporter," says Mr. Deng, a reporter-turned-activist who is well-known for founding a charity that provides free lunches for poor schoolchildren. "Before Weibo, information was monopolised by mainstream and official media, and there weren't many channels to express different voices."
Mr. Deng and others like him are at the forefront of a growing environmental movement that has become more powerful as local governments become more responsive to what is said online.
Last month, a Chinese entrepreneur used Weibo to offer a reward of Rmb 200,000 ($32,000) if the top environmental official in Rui'an, in Zhejiang province, swam in a polluted river. A week later, China's national broadcaster featured an interview with the squirming official, who promised to swim in the river sometime within three to five years.
In Weifang prefecture the government was quick to respond to Mr. Deng's Weibo post. As the post went viral, the city's propaganda department asked the local environmental protection bureau to investigate.
The environmental bureau conducted checks on more than 700 factories in the county – and within three days issued a statement saying that none of them were pumping wastewater underground. The bureau set up a hotline for tips on environmental violators, promising a reward of 100,000 yuan to anyone who could find the allegedly polluting deep wells.
"The reason we offered the prize is that we need the power of all the people, not only the government and the media, to solve this problem," said an official at the environmental bureau in Weifang, who spoke on condition of anonymity because he was not authorized to speak to foreign media.
The Weibo storm was also noticed in Beijing, where the ministry of environment issued a public statement specifically responding to comments made on Weibo.
Scientists say the contamination of underground streams and aquifers is becoming a significant health crisis. "What harm is caused by groundwater pollution? High rates of illness," says Zhao Zhangyuan, an expert on water pollution at the Chinese Research Academy of Environmental Sciences. "Groundwater pollution has already entered a state of extreme crisis."
Groundwater pollution is also linked to soil pollution and tainted crops, because farmers often use polluted wells to water their fields.
In the smoggy countryside where Mr. Zhang lives, farmers grow carrots, onions and potatoes – all with water drawn from wells near petrochemical plants and paper mills that discharge effluent.
China's soil pollution levels are considered a "state secret", and Beijing has refused publicly to disclose the results of a multiyear investigation into soil contamination. Activists say the government is afraid of sparking public panic if the true extent of the pollution became known.
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Despite the severity of water pollution, activists say social media could gradually make a difference.
Back in Huangjiawa, Mr. Zhang says he does not have a computer but has heard of Weibo and thinks it is a useful tool. "As an ordinary person, if the pollution has damaged my life, but I don't dare to oppose it, don't dare to say anything, then how can I live? As a citizen, no one can stop our right to speak out."
Some online activists pay a high price, however. Last weekend one environmental campaigner was badly beaten after posting about water pollution in Zhejiang province.