Dead fish found as mine dumps water

Dead fish were previously found in the lake by locals after a QMM overflow incident in Dec 2018, which was investigated many weeks later, in 2019, by the National Environmental Research Centre (CNRE) in Madagascar.

In a slide presentation to members of the public in Anosy, the CNRE suggested that the death of the fish could be caused by the presence of “brownish water” that overflowed from the mine’s “artificial swamps” during a high rainfall event. Its researchers said acidification in the swamps was most likely to blame for the fish deaths.

The need to monitor and explain changes in acidification – measured as Ph levels – was raised by experts before mining began and ever since, but has yet to be fully explored and reported. The Ph levels of the water can affect how heavy metals behave in the water and impact the environment.


In 2019, the CNRE concluded that “the phenomena of acidification and accumulation of metals in QMM basins requires deeper studies” and called for “rigorous monitoring of heavy metal concentration levels in mining basins that may impact the natural environment.”

But QMM claims that the 2018 dead fish event was not linked to the mine, and is making similar claims today. but Dead fish have been confirmed following both QMM mine water overflow incidents. Perhaps this is a coincidence.

The CNRE report has never been published openly or made available locally, despite repeated and ongoing requests from local communities and also international civil society.

Local villagers have become increasingly concerned about water quality locally since the QMM operations began and these anxieties have been supported by a series of independent studies that have demonstrated that the mine is having a detrimental impact on water quality in the region.


These studies have found elevated levels of uranium and lead in the waters downstream of the mine – sometimes 50 and 40 times higher respectively than the WHO safe drinking water guidelines. 

Dr Stella Swanson, an internationally recognised radioactivity expert, has demonstrated that the QMM mine basin water that is moved into the QMM settling ponds contains elevated levels of radionuclides. This processed water is released via settling ponds and wetland swamps into the environment. Unfortunately, Madagascar currently has no legal limits set for the discharge of uranium into the environment.

The water around Mandena is used for drinking and in homes. It also provides a feed into Lake Lanirano, which in turn supplies drinking water to residents in the town of Ft Dauphin. Civil society actors have therefore argued that World Health Organization (WHO) safe drinking water guidelines must apply.

Indeed, QMM did made a commitment to use WHO and Canadian standards for water quality in its 2001 Environmental Management Plan.


Communications around the mine tailings dam failure incidents has also been inadequate. Local communities have complained that QMM only announced they were releasing the million cubic metres of mine waste water after they had started. 

QMM has insisted there is no environmental impact or risk. The company also claims that interim studies by their external provider, JBS&G, indicate there is no cause for concern.

However, the state investigations are still underway and no public conclusions of results are yet available. And the JBS&G interim reports are themselves far from conclusive.

One states: “All results, conclusions and recommendations should be reviewed by a competent person with experience in environmental investigations, before being used for any other purpose (JBS&G 2021).”

Dr Swanson has studied three JBS&G interim reports, and issued a Memo with recommendations which raises questions as to whether the JBS&G study can deliver what is needed to determine the impacts of the QMM mine and produce credible results. 

Civil society organisations Publish What You Pay (Madagascar & UK) and Andrew Lees Trust have been jointly advocating that Rio Tinto immediately provide safe drinking water to the impacted communities, manage the QMM mine process water safely and improve transparency about the mine operations.

The continued failure to respond adequately to the concerns raised by the local communities and civil society has meant that after a decade of operations QMM is still failing to meet the needs and address the concerns of those who are being impacted by the mine operations. 

Right of Reply

A statement from the QMM provided to The Ecologist said: “QMM has made good progress on water management and has developed a water management plan aimed at minimising water release and impacts of the receiving environment.

“Given the specific geographical challenges of Madagascar and the growing exposure of the country to climatic extremes, QMM has taken a new step in the implementation of this strategy. A process water treatment unit is currently under construction to improve water management and manage similar exceptional situations that may arise in the future.

“In 2019, we commissioned JBS&G to conduct an independent study on radiation and water quality around our mine. The study will be completed by the second quarter of 2022 and then it will be cross-examined by the Malagasy regulator.”

The statement added: “From the analysis received to date – there have been two rounds of investigation – there is no result that triggers immediate action [needed] to prevent any human harm to the community. Once completed and cross-examined by the regulator, the full results will be disclosed, shared, and discussed with the communities and key stakeholders.”

The statement also spoke to some of the specific concerns raised by The Ecologist. “Water overflow: In February 2022, Fort-Dauphin experienced very high levels of rainfall, which may have impacted the natural environment.

“We have investigated the possible link between the water quality concerns reported twice by the community and QMM’s one-off overflow incident that happened on 17 February. The results of the investigation show that the incident caused no impact on the receiving environment. Full results and conclusions will be shared and discussed after a further ongoing investigation conducted by the regulator are completed.”

The company also addressed the concern about dead fish. “The February 2022 heavy rains put QMM’s water system under pressure. In a proactive approach designed to avoid any uncontrolled overflow into the natural environment and with the authorization of the regulator, QMM started a controlled water release on 8 March. This was announced publicly before the release began.

“Daily water quality monitoring shows no anomalies that could impact the receiving environment. QMM is undertaking an investigation to establish any causal links between the water release process and the dead fish incident, noting however that no dead fish were found at the location where QMM was releasing water, nor in the river into which the water flows.”

The statement concluded: “QMM is contributing to a programme to provide access to potable water for the three communities neighbouring QMM’s mine and has made a large donation to a post-cyclone emergency aid.”

This Author

Yvonne Orengo is the director of the Andrew Lees Trust (ALT UK) a British charity set up following the death of Andrew Lees in 1994. She lived and worked in southern Madagascar to develop social and environmental programmes and has followed the evolution of the Rio Tinto/QMM mine for more than twenty six years.


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