It's just dirt, often just the ground we stand on, our children play on, or our homes are built upon. But sometimes this dirt is a killer and people are just discovering how to handle this.

Six months ago the authorities conducted blood tests on 1,306 children in a residential compound in Pudong New Area. Forty-nine children had unsafe levels of lead in their blood and most were aged just 1 to 3 years, according to an official report released last month.

Gu Jingjie and his family live in the compound. His two children, a 2-year-old daughter and a 9-year-old son, have been receiving treatment in a hospital for months. The concentration of lead levels in their blood was three to four times the normal. To completely remove the lead from their bodies could take years. "We are living in worry and fear," Gu told the Global Times.

This residential compound is adjacent to an industrial zone. The city government's report has blamed three businesses for the lead poisoning: Johnson Controls, a US top 500 company manufacturing car batteries; Xinmingyuan, a vehicle repair factory; and Kangshuo, a waste recycling company.

The report concluded that poisoning had been caused by the long-term accumulation of discharged lead pollutants into the neighboring environment. The three companies were ordered to halt lead-related operations and to clean the contaminated soil.

Children especially can contract lead poisoning because they live and play on open ground when they can. Lead poisoning can affect the major organs of the body and cause anemia, headaches, stomach pain, comas and death.

The Pudong incident is perhaps just the tip of a contamination problem that could affect different areas in the city. To treat soil polluted this way requires soil remediation, a complex and expensive process. 

Heavy metal dangers

As a major industrial city last century, Shanghai was, like most industrial cities, a producer of a variety of chemical and other pollutants. According to Shanghai government records, from the 1960s the soil of certain areas in the city was polluted with uncontrolled sewage and industrial pollutants. Heavy metals and total volatile organic compounds (TVOC) are the major pollutants found in contaminated soil in Shanghai.

Although the sources of pollution have been controlled since the 1980s, most polluted areas remained polluted because heavy metals are very stable and unlikely to break down.

Shanghai was one of the first cities in the country to attack the problem of soil contamination. In a nationwide survey in 2006, the Shanghai Environmental Protection Bureau admitted there were varying degrees of pollution as a result of past industrial development.

The bureau stressed that any land found with contaminated soil could not be sold or developed until the soil had been cleaned.

He Chiquan, the director of the Environment and Chemical Engineering Department at Shanghai University, told the Global Times that the problem was exacerbated in Shanghai in recent years because of the speed of the city's development.

"Shanghai used to have many heavy industry factories downtown and they were forced to close or were relocated elsewhere to make room for the development of the local economy," He said.

"The World Expo 2010 in Shanghai revealed the extent of the problem and the event marked when soil remediation - cleaning contaminated soil -  officially came to public attention," said Huang Shenfa, deputy director of Shanghai Academy of Environmental Sciences, the research institution under the Shanghai Environmental Protection Bureau, which carries out most of the soil remediation in the city.

In 2002 China won its bid to host the World Expo 2010 in Shanghai. The following year soil remediation began at Expo Park sites. In 2005 the Shanghai Academy of Environmental Sciences established the Shanghai Center for Soil Remediation.

Since 2005 the center has completed more than 20 major projects (including Expo Park, subway stations and residential compounds) that were being built on contaminated soil. More than 400,000 cubic meters of contaminated soil and 20,000 tons of underground water were treated (polluted water can also be cleansed with remediation).

Currently the center is working on comprehensive remediation for the Shanghai Disneyland project in Pudong and the Nanda area development in Baoshan district which involves 1,000 factories being shut down over the next five years to make room for residential compounds.

"The World Expo project was the first large-scale soil remediation work in China and it showed that we have developed a feasible and effective method of soil remediation," said Li Yun, the senior engineer and director of the Marketing Department of the Shanghai Academy of Environmental Sciences. She led the team which drafted the standards for evaluating the soil remediation at the Expo Park.

In this particular zone, which once housed a steel manufacturing factory, the soil was largely contaminated by heavy metals and TVOC.

Li said her team used advanced solidification-stabilization technology to remove the heavy metals from the soil and biopile technology to clean the TVOC pollutants. "The remediation has proved very successful and it was approved by all the Expo participating nations," Li said.

The standards Li drafted were later submitted to the Ministry of Environmental Protection and officially published as the country's first remediation standards in the Standard of Soil Quality Assessment for Exhibition Sites published in 2007.

 

Emerging industry

Soil remediation is an emerging industry in China, born as a result of its rapid economic development and the expansion of the real estate industry.

According to a 2010 World Bank report, "Overview of the Current Situation on Brownfield Remediation and Redevelopment in China," the soil pollution problem can be traced back to the period of The Great Leap Forward (1958-61), when many highly polluting industrial plants were built throughout the nation.

After years of pollution some soil areas were contaminated several meters below the surface and were hundreds of times above the recommended safety levels. Areas like this had to be made safe before being redeveloped, the report said.

From 2001 to 2009 at least 98,000 industrial plants were closed and relocated, noted a nationwide study by the Chinese Society for Environmental Sciences. The relocations left huge amounts of contaminated land, much of its in downtown urban areas, which were set to be redeveloped as commercial or public ventures. In those days few people thought the ground underneath them would be toxic.

But in 2004 after a group of construction workers passed out at the same time while working on a new subway station site in Beijing, the public began to pay attention. "The remediation industry actually started then," said Xiong Jian, the deputy director of the Soil and Underground Water Department at the Chinese Society for Environmental Sciences, who led the study.

Xiong believes pollution has an incubation period before it reveals its dangers - like the Minamata disease in Japan in the 1950s and 60s when no one understood for 10 years that mercury poisoning was causing the mystery illness and deaths.

Legally unclear

Wang Wei, the managing director of the Shenzhen-based Cowin Venture Capital Corporation, told the China Securities Journal that the rights and responsibilities of many industries that could cause pollution in China were legally unclear. The internationally-accepted rule that the person who pollutes cleans the pollution up could not always be applied in China. "As well as a few commercial projects where real estate developers pay, most contaminated soil remediation programs are currently covered by government money or bank loans. But looking at the number of remediations required it would be unrealistic to rely on this financing," Wang said.

According to the Guangzhou-based Southern Weekend newspaper, an average soil remediation treatment could cost 100 million yuan ($15 million). There are also huge profits, some say 50 percent, for the company carrying out the work.

But despite the growing demand there are only a few professional bodies working in the field. Huang, from the Shanghai Academy of Environmental Sciences, told the Global Times that sometimes the academy was "too busy to handle some projects."

An official surnamed Wu, from Entech China Limited which is associated with the Australia-based environmental company ToxFree in Shanghai, said the remediation industry in Shanghai is not transparent and too small at present to meet the demand.

"Many remediation firms believe contaminated soil is like a Pandora's box - you cannot know how deeply polluted an area is before you start work," said Gao Shengda, the editor in chief of China Environmental Remediation.net, a web portal for the industry. Because of the nature of the issue, most developers would rather not talk about remediation, Gao said.

Luo Qishi, director of Shanghai Center for Soil Remediation, has outlined the proper procedures for soil remediation work: a preliminary investigation, a pollution evaluation, health risk evaluation, a remediation plan and implementation. There should also be a third party monitoring the process.

"For most major and public projects, we are confident that Shanghai is doing the right thing. But for some small commercial projects, it's hard to say," Luo said. 

Hidden threat

For some time experts have been urging the authorities to pay closer attention to the problem of contaminated soil. Shen Jianhua, a senior researcher at the Shanghai Institute for Biological Sciences of the Chinese Academy of Sciences said that contaminated soil has become a hidden threat for the environment and public health in Shanghai.

"These 'brownfields' are usually found downtown and always being sought by real estate developers. It is a concern when management policies and regulations are lax," Shen said.

He said that over the past 20 years, because of the rapid development of the economy and human activities, environmental pollution became more complex. It can now combine multiple pollution sources from everyday living, agricultural and industrial sources. And that makes remediation even more difficult.

"We lack detailed laws and national standards that give a clear guideline for which kinds of soil need repairing, how deep the remediation should go and who should supervise this," Shen said.

In a proposal he sent to this year's annual meetings for policymakers and political advisors, he asked for the establishment of a database, which would contain all the city's information about contaminated soil areas.

Chen Ling, the director of the Environmental and Engineering Science Department at Tongji University, agreed. "The value of land is worth a lot more than the cost of remediation. The city government could encourage the real estate market to take part in remediation programs to solve the cost issue. As well it's important that the authorities allocate money in annual budgets to support this critical work," she said.