SHENYANG - While the chimneys of the Shenyang Smelting Plant were easily dismantled in 2000, the heavy metal-contaminated soil under and around the plant was a much more difficult foe to tackle.

However, a new soil treatment method used to decontaminate the area five years ago has shown remarkable results. Lush lawns and bright shopping malls now stand in place of the demolished plant and its surroundings in the city of Shenyang, capital of Northeast China's Liaoning province.

The task of cleaning up the soil around the plant was left to the Shenyang Academy of Environmental Sciences, which was recognized for its efforts in the form of an award for scientific progress given by the city government in August this year.

Wan Bentai, former chief engineer of the Ministry of Environmental Protection, said that the technological achievements demonstrated through the reclamation of the contaminated area set a powerful example for environmental protection efforts elsewhere in the country.

Chen Hui, the decontamination project's leader and a chief economist from the Shenyang academy, said that an environmental impact assessment conducted in the area showed that more than 60 percent of the 360,000 square km of land surrounding the plant was heavily contaminated by heavy metals, including cadmium, chromium and lead.

Chen and his team members first worked to classify the polluted soil into three categories, sorting them by density of contamination. The most heavily polluted soil was simply shoveled away and transported to landfills. Soil that was slightly to moderately polluted was treated with a unique chemical reagent that absorbed the heavy metals in the soil.

The project is the largest of its kind in China and involves the application of a multitude of new and innovative environmental decontamination technologies. The value of the land treated during the project has risen by 730 million yuan ($114 million), offsetting the 120 million yuan spent by the city government to fund the project by a large margin.

Li Songlin, head of Shenyang's Tiexi District government, said Shenyang has a tremendous task to accomplish in treating the pollution left over from its previous role as one of the country's most important industrial centers. He said the Shenyang Smelting Plant used to be the city's biggest polluter, accounting for 42 percent of the city's total sulfur dioxide emissions and 98 percent of its lead dust emissions.

Environmental experts from the China Environmental Sciences Institute have called for more applications of soil decontamination technology across the country, as heavy metal pollution has been blamed for a number of serious health problems in recent years.

Earlier this month, a chemical firm in the city of Qujing in Southwest China's Yunnan province, was found to have illegally dumped over 5,000 metric tons of chromium-contaminated waste near the Chachong Reservoir, threatening drinking water supplies for ten millions of residents living downstream.

The provinces of Henan and Guangdong have reported a number of lead poisoning cases in recent years, drawing nationwide attention. Hundreds of rural residents in those provinces were found to have excessive levels of lead in their blood after living in heavily polluted areas.