Adani Australia's chief executive officer was in charge of an African copper mine which allowed a flood of dangerous pollutants to pour into a Zambian river, the ABC can reveal.

Jeyakumar Janakaraj has been chief executive of Adani's Australian operations since leaving Konkola Copper Mines (KCM) in Zambia in 2013.

Now KCM and its parent company Vedanta Resources are being taken to the High Court in London by locals who say pollution from the company's huge Chingola open-pit copper mine made them ill and devastated nearby farmland over a 10-year period from 2004.

Mr Janakaraj was director of operations of KMC when the company was charged in 2010 with causing a serious pollution spill, which saw a toxic brew of highly acidic, metal-laden discharge released into the Kafue River.

The river is one of Zambia's largest waterways and a source of water and food for about 40 per cent of the country's people.

Got a confidential news tip? Email ABC Investigations at investigations@abc.net.au For more sensitive information: Text message using the Signal phone app +61 436 369 072 No system is 100 per cent secure, but the Signal app uses end-to-end encryption and can protect your identity. Please read the terms and conditions.

The 31-square-kilometre KCM open pit mine in Zambia's Chingola region is described as the biggest copper mine in Africa, producing about 2 million tonnes of ore a year.

The 2009 annual report of KCM's parent company, London-listed mining conglomerate Vedanta Resources, said Mr Janakaraj was "responsible for overall operations of KCM".

"On [Mr Janakaraj's] watch, significant pollution events happened," lawyer Ariane Wilkinson of Environmental Justice Australia said.

"The court documents show that they discharged what's called a pregnant liquor solution into the Kafue River. That's a highly acidic, metal-laden pollutant, and that it changed the colour of the river."

KCM was prosecuted by the Zambian Government, and the company pleaded guilty to charges of polluting the environment, discharging toxic matter into the aquatic environment, wilfully failing to report an incident of pollution, and the failure to comply with the requirements for discharge of effluent.

The court was told the source of the contamination was the mine's tailings leach plant, with the pollution changing the colour of the Kafue River to "deep blue". The company was fined 21,970,000 Zambian kwacha (about $4,030).

A few months later, in 2011, a Zambian newspaper reported the company's copper mine had again polluted the river, and that environmental authorities were investigating.

Chingola mine is described as the biggest copper mine in Africa, producing about 2 million tonnes of ore a year. ( Leigh Day lawyers, London )

Residents became ill, crops devastated by toxic water: lawyer

The 2010 prosecution was not the only successful claim against the mine for pollution.

In 2006, before Mr Janakaraj's time with KCM, the company discharged harmful effluent into the river, polluting Chingola's town water supply.

In 2011, while Mr Janakaraj was the company's chief executive, the Supreme Court of Zambia upheld a claim over that incident brought by 2,000 Chingola residents.

An earlier High Court case decision on the case ruled KCM "was reckless and had no regard for human, animal and plant life".

"You've just got a very continuous, slow, regular process of pollution in the area. And we hope to make them pay," lawyer Martyn Day of the London-based firm Leigh Day said.

Mr Day is representing 1,800 Zambians in a claim against KCM and its parent Vedanta in the High Court in London.

The residents of four villages near the copper mine allege a series of discharges of sulphuric acid and other toxic chemicals into waterways over a decade since 2004 have made them sick and devastated their crops.

"A lot of the crops are dead, a lot of the area nothing grows," Mr Day said.

"A very large proportion [of the claimants] are saying that they've suffered a serious illness, respiratory complaints, they can't breathe, problems with their eyes."

Mr Day said the period between 2008 and 2013, when Mr Janakaraj was KCM's director of operations and then CEO, was a time when the levels of pollution were bad.

"I would say that there are many questions one would want to put to this chap, as to what he knew, what he was aware of at the time, how all of this was going on under his watch."

The ABC understands the claim lodged in the High Court in London on behalf of the Zambian claimants names Mr Janakaraj as one of the company executives expected to have detailed knowledge about KCM's mining operations and its pollution control measures.

The Kafue River is one of Zambia's largest waterways and a source of water and food for about 40 per cent of the population. ( Leigh Day lawyers, London )

Lawyers appeal to governments to consider Adani chief's history

According to Adani, Mr Janakaraj oversees "all Adani operations in Australia, including the implementation of the Carmichael coal mine and rail project".

The $16.5 billion project would see the construction of six open cut pits and five underground mines ranging over 200 square kilometres in the Galilee Basin in central Queensland.

It would be the biggest coal mine in Australian history.

Some conditions imposed on Adani: Implement advice from Independent Expert Scientific Committee on Coal Seam Gas and Large Coal Mining Development

Implement advice from Independent Expert Scientific Committee on Coal Seam Gas and Large Coal Mining Development Protect and improve 31,000 hectares of southern black-throated finch habitat

Protect and improve 31,000 hectares of southern black-throated finch habitat $1 million research funding to improve conservation of threatened species over 10 years

$1 million research funding to improve conservation of threatened species over 10 years Protect Doongmabulla Springs through monitoring of groundwater and triggers to enforce limits

Despite legal challenges by conservation groups, Federal Environment Minister Greg Hunt approved the project subject to "36 of the strictest conditions in Australian history".

But environmental lawyers in Australia, the United States and Britain have told the ABC the minister failed to take Mr Janakaraj's history, in relation to environmental matters, into account.

Mr Janakaraj declined to be interviewed by the ABC. Responding to questions about the 2010 prosecution of KCM and Mr Janakaraj's position of responsibility at the company, his Adani spokesman referred the ABC to KCM's parent company, Vedanta Resources.

"Mr Janakaraj has wide-ranging experience that has contributed to his acute belief in proactive good environmental management," the spokesman said in a statement.

"He is confident that he has always worked to improve practices and leave projects in better shape than he found them."

Environmental Justice Australia and the United States environmental law group, Earthjustice, have submitted a report to Queensland's Environment Department and to Mr Hunt, calling on them to consider the information about Mr Janakaraj's time with KCM in Zambia.

"Under both Queensland and federal environment laws in Australia the environmental record of the executive officers of a company is relevant when we look at the company and character check them to see whether they can be trusted and comply with conditions," Ms Wilkinson said.

"So the fact that Mr Janakaraj comes to Australia with this environmental record from Zambia is absolutely relevant to whether Adani should be able to operate in Australia and hold environmental approvals."

The ABC asked Mr Hunt's office if Mr Hunt was aware of KCM's environmental record in Zambia and Mr Janakaraj's background with the company.

A spokesman said "the issues raised were not within the material provided to the [Environment] Department by the proponent [Adani] ... the Department will seek clarification from the proponent on the issues raised".

The National Party member for the federal seat of Dawson in central Queensland, George Christensen, supported the Carmichael project.

He spoke to 7.30 at Brisbane airport after returning from a tour of Adani facilities in India, where he met with Mr Janakaraj.

"All I know [the incidents were] in Zambia, a third-world country, very different environmental standards, very different environmental monitoring and conditions as opposed to Australia where it is a high level," he said.

"I think that the green movement when they start attacking employees — and essentially Mr Janakaraj is an employee of Adani — when they start attacking the personal character of employees they really are clutching at straws."

Adani's full statement:

"Mr Janakaraj has wide-ranging experience that has contributed to his acute belief in proactive good environmental management. "This is based on his early experience in Australia, where that respect for stringent management was part of the culture, and because he has seen around the world both directly and indirectly how hard managing legacy issues is. "That includes the need to assist in managing legacy issues in Africa. He is confident that he has always worked to improve practices and leave projects in better shape than he found them. "That experience is why, as part of Adani's Australian projects, the team is proactively working within most stringent environmental conditions ever laid down in Australia, and Adani took a leading role in developing options to ensure disposal of dredged material could be brought onshore, rather than offshore, which had been the practice in that area for decades — well before Adani took over management of the Abbot Point Port. "It is worth noting that Adani has maintained a strong and active role in good management of the Abbot Point Port, so not only does Mr Janakaraj bring the experience of seeing what works and what needs to be improved, but he has a proven track record of good management here in Australia as well. "Questions relating to KCM operations should be directed to the parent company, Vedanta Resources.