About one-tenth of the roughly 5,000 proposals submitted to the country's top political advisory body since the two sessions began on March 3 are related to environmental protection, a top national political adviser has said.

Luo Fuhe, executive vice-chairman of the China Association for Promoting Democracy Central Committee, revealed the figure at a meeting on pollution control that included CPPCC members and top officials from eight ministries.

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A working plan relating to groundwater pollution prevention and control in the North China Plain was released on Friday and is aimed at setting out a rough picture of the current pollution situation before 2015.

The plan, jointly issued by four ministries, including the Environmental Protection Ministry and the Water Resources Ministry, set a target to build a complete monitoring network of the region's groundwater quality and sources of pollution by 2020.

The results of the first stage of the investigation will be announced to the public by 2015, Chen Ming, deputy head of the Water Resources Department at the Ministry of Water Resources, told China Daily.

Chen said groundwater quality nationwide is, "better in the mountainous regions than in the plains, and quality of deep groundwater is better than of shallow groundwater".

"That's why the North China Plain, where the pollution situation is relatively bad, has been chosen as the first target to combat groundwater pollution," he said.

The plan divided the region and the key source areas of its groundwater system into 30 plots, emphasizing five major pollutants to prevent and control, including heavy metal and organics.

Recent media reports said 55 percent of the country's groundwater has been polluted, but Chen did not confirm the figure.

"About 30 percent of China's groundwater is good enough to be used as drinking water, ranging from level I to level III. The water quality of the other parts is at Level IV or below," said Chen.

But he added that this does not mean 70 percent of groundwater is polluted, because the No 1 pollutant in China's groundwater is fluorine, a natural element.

Allegations of companies in Shandong province pumping wastewater 1,000 meters into the ground spread online in February.

Chen said official investigations failed to unearth any such activity, but they did uncover, and fine, several factories for digging shallow holes or wells about 5 meters deep, to discharge their sewage which polluted shallow groundwater.

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