The facilities of a southwest China chemical plant behind recent health scares will be sealed until all its hazardous waste has been properly treated, authorities promised Monday.

The stance of the county government of Qujing, Yunnan province, came weeks after media reports accused the scandal-dogged Luliang Chemical Industry Co, Ltd. of ignoring a government ban on operations.

A spokesman for Qujing government on Monday defended the company, saying that the part that continued in operation was not covered by the ban because it did not create chromium residues, a carcinogenic industrial chemical suspected of polluting local water supplies over the years.

The authorities would strengthen supervision of the plant to properly dispose of about 25,000 tonnes of chromium residues by the end of the year and another 148,400 tonnes in 2012 before lifting the ban, the spokesman said.

Local police in August detained five Luliang Chemical Industry Co. employees associated with the plant's dumping of 5,000 metric tonnes of untreated chromium residues from April to June. Rainfall washed some of the chemicals into local water supplies, causing the deaths of 77 heads of cattle.

No human deaths have been attributed to the area's chromium pollution, but at least 14 local residents have been diagnosed with cancer since 2002. Many suspect their illness was caused by contaminated drinking water.