The central government has pledged to launch a national program to speed up efforts to control and improve the country's soil protection.

The pledge was made during an executive meeting of the State Council on Wednesday chaired by Premier Wen Jiabao.

At the meeting, the State Council decided to strictly protect the soil of farmland and nearby drinking water sources by bringing pollutants under control. In addition, it resolved to set up programs to rehabilitate polluted soil and to improve the supervision of soil.

The State Council's call for attention to soil in the environment was motivated by the first national survey of soil pollution, which found that China's soil has been seriously polluted by industrial, mining and farming activities. The survey was launched in 2006 by the Ministry of Environmental Protection.

At that time, the figures given by Zhou Shengxian, now head of the ministry, was that about 10 percent of China's farmland - 10 million hectares - was polluted.

"Wherever there is, or used to be a chemical plant, there is soil pollution," said Wang Qi, head of the institute of environmental engineering technology of the Chinese Research Academy of Environmental Sciences, and an expert on solid-waste treatment.

Wang said there are two categories of soil pollution: on farmland and at contaminated sites. He participated in a national investigation of the second category, which is found mainly around chemical plants, where pollutants are present in concentrations hundreds or even thousands of times as high as on farmland.

"Sewage discharged by factories, particulate matter from exhaust sedimented by rain, and the excessive use of pesticides and fertilizers are the three sources of soil pollution," he said, adding that industrial sources are the main culprits.

Pollutants in the soil can escape into the air as vapor or dissolve in groundwater and contaminate rivers and lakes, posing a lethal threat to public health.

Wang said the current situation will not improve without industrial restructuring, such as promoting the development of high-tech and service industries.

"There has been a trend in recent years for chemical industries to move from coastal areas to the hinterland," he said. "Because local governments value how industries stimulate the local economy, local protectionism is always a tough issue when pollution is found.

"Ecological compensation is also important," said Wang. "Inland settlers' economic sacrifice to protect the environment should be recognized and compensated, so that they can find another way to make a living."

He said the extent to which soil pollution can be solved depends on the central government's determination to tackle the issue.

An Environmental Protection Ministry plan to protect the soil environment nationwide from 2011 to 2015 has been submitted to the State Council for approval, according to Hou Daijun, deputy head of the ministry's Nature and Ecology Conservation Department.

Under the plan, the central government alone would invest up to 30 billion yuan ($4.81 billion).

But Wang said pollution control in soil, especially at contaminated sites, is so costly that it is not unusual to spend as much as 10 million yuan on a single site.

wuwencong@chinadaily.com.cn