Rehabilitation work is carried out on land in Heshan that was formerly used for a pesticide factory, in Wuhan, Hubei Province, on March 2. Photo: CFP

In downtown Suzhou, a city in East China's Jiangsu Province noted for its beautiful parks and traditional lakeside architecture, sits 40 hectares of land that has been deserted for six years. Tall weeds and garbage abound, a stark contrast to the neighboring high buildings and busy roads. 

The land was found to be heavily contaminated with organic materials such as phosphorus, benzene and heavy metals such as arsenic, cadmium and lead after a 50-year-old chemical plant was relocated in 2007.

The local environment protection authority is mulling remediation methods, ranging from changing the soil to neutralizing it with limestone. The pollution goes three to five meters deep and the cost of fixing the problem is estimated at 1 billion yuan ($164 million).

This is by no means a rare case in China. Zhang Junli, a researcher from the solid waste and chemicals management center with the Ministry of Environmental Protection (MEP), revealed at a land rehabilitation forum in October that there could be more than 500,000 polluted land blocks around the country.

China's rapid urbanization has resulted in many industries moving out of urban areas to make room for the influx of migrants. Much of the land left vacant has turned out to be heavily polluted and unsafe for human habitation, becoming a burden on local governments.

When Chongqing conducted an evaluation of sites left after the relocation of industrial plants, it found that 84 out of 233 were contaminated. In an appraisal in Beijing, 21 sites out of 80 were found to have pollutants. The problem is especially serious at sites where chemical, iron and steel, metallurgy and mechanical engineering factories were previously located.

Turning point

For Liu Ke, vice president of the Beijing Jinyu Mangrove Environmental Protection Technology Co. Ltd, an incident in 2004 that occurred during the construction of Beijing subway Line 5 was a turning point for awareness on the Chinese mainland of land rehabilitation and redevelopment of industrial polluted sites.

In April 2004, three workers suffered severe nausea despite wearing gas masks while digging a ditch for the line's Songjiazhuang station. The land had previously been the site of a pesticide manufacturer.

Since then, more poisoning cases from construction sites have been reported. In 2006, six workers fainted while building a road in Suzhou on land that used to belong to a chemical factory. In 2007, several workers were poisoned during real estate development work in Heshan, Wuhan, capital city of Central China's Hubei Province.

The land, where a pesticide maker was previously located, was later found to be severely polluted. The local government was forced to pull the plug on the project and pay compensation of 120 million yuan to the developer.

Similar cases in other countries show that toxic lands can harm people's health through dust, water and air, and symptoms will only show in 10 years or even more.

Inevitable trend

However, the closing or relocation of old industrial and mining plants and redevelopment of these sites will be an inevitable trend for urbanization, Zhang Junli believes.

She estimates that the urbanization rate of China will surpass 70 percent from the present 50 percent and 12 billion square meters of land will be needed to meet housing demand for the growing population in urban areas.

By 2007, about 200 industries had moved out from within Beijing's fourth ring road, leaving about 9 million square meters of land vacant. From 1992 to 2007, Shanghai relocated 210 factories, while in Guangzhou, Guangdong Province, about 500 polluting firms are scheduled to move out by the end of 2015.

Insiders estimate that at least one-fifth of these sites are heavily polluted.

 "You have to always prepare against the monsters emerging from under your feet," was how one unidentified land remediation professional described his work to the Phoenix Weekly.

Pollutants in China are often large in scale and complicated in their formation. At a polluted site, it is common for heavy metals, electronic waste, petrochemicals and sustainable organic pollutants to coexist.

Most polluting enterprises were built between 1950 and 1970, when priority was given to productivity but treatment and prevention of the three main wastes, namely waste gas, waste water and industrial residue, were neglected.

Soil pollution has prompted growing concerns from both the government and the public in recent years. As factories moved to rural areas, they have also brought pollutants there.

In May, the Guangzhou food regulator found that over 44 percent of rice and rice products tested in the city had high levels of cadmium. The carcinogenic metal can seriously damage the kidneys and cause other health problems. The cadmium-tainted rice was verified as coming from Hunan Province, one of the country's largest rice producers.

Experts attributed the finding to soil polluted with heavy metals in the province, a result of exhaust emissions and waste discharge from factories, as well as excessive use of pesticides and fertilizers.

As early as 2006 in Hunan's Zhuzhou, a total of 1,100 villagers were found to have excessive cadmium levels. Later, the Xiangjiang River crossing the city, whose upper reaches are home to many industrial plants, was fingered as the source of the poisoning.

In February 2012, a total of 96 children in Renhua, Guangdong were found to have excessive lead in their blood. In June 2012, about 200 children in Jiangsu's Nantong were found to have the same problem.

Need to know

Data widely quoted by media showed that as much as 20 million hectares, or one-sixth of the country's farmland, has been polluted by heavy metals, but this has not been verified by the government.

In 2005, the Ministry of Environmental Protection and the Ministry of Land and Resources initiated a nationwide investigation into soil pollution. But so far, the results have not been announced, despite widespread calls to do so from media and experts.

Some speculated that the results must have been so serious that authorities refused to disclose them for fear of causing panic.

As early as in 2006, the Environmental Protection Minister Zhou Shengxian said that heavy metal-tainted grain totaled 12 million tons each year and that direct losses exceeded 20 billion yuan.

"As far as I know, the amount of polluted land surpassed 10 million hectares from the late 1990s to 2009, and pollution in some areas is so serious that the land can no longer be used for farming," Wang Shuyi, director of the Research Institute of Environmental Law at Wuhan University, told the Nanfang Daily in May.

How to restore these lands has become an awkward issue for China.

Estimates by the US Environmental Protection Agency showed that the remediation of a contaminated site of several hundred square meters would cost at least $50 million.

In China the cost can be even higher due to the diversity of the pollutants and the severity of the pollution. In Wuhan's Heshan, a rehabilitation project for 16 hectares of land will cost at least 280 million yuan, according to the local authority. The land remediation launched in May 2011 is expected to be finished by May next year.

The measures mainly used are soil removal and incineration, as well as biochemical reduction technology. Seventy-three percent of the soil will be moved away and incinerated, the remainder will be treated in rotary kilns, and toxic pesticides will be destroyed through high temperatures.

Land remediation in Suzhou could cost up to several billion yuan.

While regulations state that the polluter has to shoulder the costs, in reality, the responsibility always falls on local governments.

In most recent enterprise relocation cases, the firms are State-owned and the lands allocated to them by the government. Because they have handed most of their profits to the government, it becomes difficult to demand that they pay for the treatment of the pollutants they leave behind.

Reckless measures

Excessive input and reckless treatment methods also present concerns.

"Due to uncertainties regarding the investigation and evaluation technology, the risk management of the polluted sites will be conservative, which will result in excessive treatment," observed Jiang Lin, vice president of the Beijing Municipal Research Institute of Environmental Protection.

For a restored site to get the green light in China, all the sampling points have to meet unscientific standards, which will lead to excessive remediation, Jiang said.

In addition, the same site can fulfill the lower standard if it is used for commercial instead of residential use, which takes less time and costs less money, he said.

Adding to the problem, China lacks experience in land remediation. "China doesn't even have any symbolic soil remediation project available for others to follow," said Li Fasheng, chief engineer at the Chinese Research Academy of Environmental Sciences.

In Wang Shuyi's mind, the more urgent task is to establish a law on soil pollution prevention and control. Wang, at the invitation of the MEP, has been drafting such a law since 2006 together with other environmental protection experts.

In the draft, they highlighted citizens' awareness of the soil situation and establishing archives and control zones for polluted lands.

"The archives will help trace the soil situation. Control zones will be defined based on the pollution severity and restrict certain economic activities. If the pollution is serious, the activities will be completely prohibited," Wang said.

The law will be issued within three years, according to Wang.

Phoenix Weekly-Global Times