Mining firm culprit

Yizhou, the site of the Lalang hydroelectric station, is 55 km downstream from where the Jincheng and Longjiang rivers join at Hechi city. A task force from the city's environmental authority traced the distance.

The authority reported that it examined 145 factories and found that 11 did not meet standards for environmental protection. Of the 11, seven were held responsible for the cadmium pollution and were urged to make corrections.

Jinhe Mining, a State-owned enterprise in Hechi, is one of them.

The company, founded nearly a half-century ago as an ordnance factory, set a goal in 2010 to maintain revenue at 1.1 billion yuan with gross profit of more than 80 million yuan ($174.4 million and $12.7 million). The company said it reclaimed 300 tons of cadmium in 2011.

Jinhe's production zone is embraced on three sides by hills. At the end of a narrow swale, mineral waste residue is scattered throughout a 10,000-square-meter area. The task force said the company intentionally dumped the residue there without any processing for environmental protection, and excessive cadmium consequently leaked into groundwater.

The local government shut down the factory on Jan 18, but the air in the production zone remains smoggy. The hillsides are bare, except for a handful of green plants.

A sign nearby indicates that the residue has been dumped there since June.

When asked whether it might be a source of the river's pollution, Zeng Xinyu, the factory's production director, told China Daily: "I'm not clear."

Opaque plastic sheeting, held down by steel bars, now covers the residue and keeps out rain, which would cause the minerals to leach out.

Beside it, a dozen workers are building a concrete channel to connect the dump with a recently established plant to reclaim the waste. "The plant will be activated in four months," Zeng said. "We'll do our best to carry out the government's orders."

Workers at Jinhe Mining build a concrete channel from an area where mineral residue has been dumped to a new reclamation plant. [Jiang Dong / China Daily]