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Holding De Beers to account for mercury monitoring failure

Trevor Hesselink v De Beers Canada Inc.

December 9, 2020

De Beers Canada’s Victor Mine is nestled in the James Bay lowlands in the Attawapiskat watershed – part of the largest wetland on the planet. Victor Mine is the first and only diamond mine in Ontario with operations active from 2008 to 2019.

When the Ontario government gave De Beers the green light to mine for rough diamonds, it outlined conditions in its approval – one of them being that De Beers must report methylmercury and total mercury levels at its downstream monitoring stations.

De Beers Canada has a legal responsibility to accurately and fully report methylmercury and total mercury levels downstream from its mine. And this obligation continues despite the mine ceasing active operations in 2019.

Methylmercury is a toxin that bioaccumulates in the surrounding watershed and aquatic life, and can make its way up the food chain into humans. The reporting program was intended to act as an early warning system in case of heightened methylmercury levels downstream from the mine.

It emerged that De Beers had not reported information for five out of nine monitoring stations between 2009 and 2014, in violation of the terms of its permit. When the province failed to hold De Beers accountable for this unlawful failure to report, Ecojustice launched a private prosecution to hold the company accountable to the terms of its permit.

In 2021, after a long legal battle, De Beers pleaded guilty to one count of failing to report mercury monitoring data from the Victor Mine. As per the terms of the resolution, De Beers agreed to publicize all past and future annual mercury monitoring reports on its website. Additionally, the company agreed to pay a nominal fine of $100 and to make a $50,000 donation to charity.

Ecojustice initiated the private prosecution against De Beers for two reasons — to make sure there is accountability and enforcement of existing laws, and to make sure that in the future De Beers adequately monitors and reports the release of toxins like methylmercury.

De Beers Canada broke the law by failing to meet the reporting conditions of its permit. The Ontario government had the opportunity to prosecute those failures, but chose not to do so. As a result, we launched a private prosecution, a tool available for citizen informants to demand accountability of industry and public institutions.

What does this victory mean?

This win sends a clear message that mining and natural resource extraction companies must comply with the conditions of their permits. The case sets a precedent for mining activities in the province, including the so-called “Ring of Fire” area in Northern Ontario, and how mining pollution is to be reported and regulated.

Ecojustice staff

Zachary Biech

Julia Croome

Sarah McDonald


Wildlands League

Jul 2021
An aerial view of a large, round body of water surrounded by high cliffs.
press release

De Beers pleads guilty to failing to report mercury pollution at Canadian diamond mine

Resolution sets strong precedent of accountability for future mining projects TORONTO, ONT.
Dec 2016
An aerial view of a large, round body of water surrounded by high cliffs.
press release

Environmental group takes diamond giant De Beers to court

Failures to report on methylmercury, a neurotoxin, prompt legal action December 6, 2016 TORONTO – Wildlands League, represented by Ecojustice lawyers, has filed a private prosecution against De Beers Canada Inc.