"It is a half-baked report... There is no possibility of red mud contaminating the nearby water pond as fool-proof system is in place to avoid toxic elements getting into water," Vedanta Aluminium President Mukesh Kumar told PTI.
According to Amnesty, it has obtained video footage taken by people living near Vedanta`s Lanjigarh refinery showing two recent serious breaches of the pond following heavy rains, with gushing liquid flowing onto nearby roads.
Vedanta operates 1 million tonne per annum alumina refinery at Lanjigarh.
The Orissa State Pollution Control Board in a report dated May 5 had said that no leakage was observed from the red mud pond.
"Vedanta and the authorities must take action – with rainy season approaching the situation is a ticking time bomb.
"The red mud pond poses a serious threat to the health, livelihoods and safety of local people," Amnesty`s South Asia Researcher Ramesh Gopalakrishnan said in a statement today.
Amnesty noted the red mud pond is an "estimated 92 billion litre cocktail of toxic residue that includes radioactive elements from the process of refining bauxite".
Kumar said that the company separates dry red mud from water, which is recycled in the reprocessing unit.
"This water is utilised by the plant throughout the year. Both the ponds -- red mud and water -- have excessive thick walls. There is no possibility of dry red mud getting leaked even in the event of acute circumstances," he noted.
According to sources, pollution control board officials visited the refinery, during rains in April and May. They took samples from the site and did not find any contamination, sources added.
The state pollution control board report said, "No discharge was observed from the red mud pond or the water pond or any outlet of the industry to Bamsadhara River during the visit."
Senior board officials had visited the unit in late April.
As per the report, it may be possible that water collected in the centralised collection pit of the red mud pond during heavy rains might get into the water pond located close to the red mud pond if pumping arrangement for recycling fails.