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On May 14, 2020 the Supreme Court of Canada (“Supreme Court”) dismissed Taseko Mines Limited’s (“Taseko Mines”) application for leave to appeal a decision of the federal court of appeal. The decision of the Supreme Court resulted in the refusal of the approval for Taseko Mines $1.5-billion dollar proposed open-pit copper and gold mine. This decision represented a victory for the Tŝilhqot’in Nation, consisting of six communities, who opposed Taseko Mines’ proposal for approximately 30 years.

Taseko Mines proposed to develop an open pit gold and copper mine (“New Prosperity Mine”) located southwest of Williams Lake in British Columbia. The New Prosperity Mine was proposed to be located in the traditional territory of the Tŝilhqot’in peoples. In support of the proposed New Prosperity Mine, Taseko Mines completed a federal environmental assessment that was subject to review by a Review Panel (“Panel”). The review panel issued a report expressing concerns with Taseko Mines’ submissions about the potential seepage of toxic water.

Under section 52 of the Canadian Environmental Assessment Act, 2012 the Minister of the Environment followed by the Governor-in-Council found that Taseko Mines’ New Prosperity Mine was likely to cause significant adverse effects that could not be justified (“Decision Statement”). Taseko Mines, sought a judicial review of the Decision Statement issued by the Minister of the Environment (“Minister”) and the Governor in Council (“GIC”) pursuant to section 52 of the Canadian Environmental Assessment Act, 2012 (“CEAA 2012”) concerning its proposed New Prosperity Mine.

Following the environmental assessment, the Panel issued a report (“Report”) identifying significant concerns with the New Prosperity Mine. After reviewing the Report, the Minister determined that the Project was likely to cause significant adverse environmental effects, and the GIC decided that these effects were not justified in the circumstances. The New Prosperity Mine was rejected.

Taseko Mines challenged the Panel’s Report and the Decisions of the Minister of Environment and the Governor in Council. The issues raised by Taseko Mines on its judicial review related to whether the test for judicial review was correctly determined; if the duty of fairness can vary at different stages of the statutory process; and, if the duty of fairness interacts with the Duty to consult First Nations.

In its application to judicially review the Minister’s and GIC’s Decisions, Taseko Mines alleged breaches of procedural fairness and jurisdictional errors, as well filing a constitutional challenge to sections 5(1)(c), 6 and 7 of the CEAA 2012. Taseko Mines also brought a judicial review application against the Report.

The Federal Court confirmed that Taseko Mines was owed some degree of procedural fairness which was satisfied in the circumstances and the constitutionality of sections 5(1)(c), 6 and 7 of the CEAA 2012.

When the Minister was making her decision, she confirmed that Taseko Mines was owed a minimal degree of procedural fairness and, in fact, received a significant degree of procedural fairness. Taseko Mines made post-Report submissions, which were before the Minister when she made her decision.

During the GIC’s decision-making process, no duty of procedural fairness attached to the GIC. The GIC is generally free to exercise its power without Court interference provided that there is no absence of good faith and the statutory preconditions have been met, which was not argued by Taseko Mines. Even if the GIC did owe Taseko Mines a duty of fairness, the content of such a duty would be minimal and it would have been satisfied in this instance.

Several intervenors were involved in the case, including MiningWatch as represented by Ecojustice. MiningWatch intervened to reinforce the integrity of the environmental assessment process. The Federal Court agreed with the position taken by MiningWatch that one of the core purposes of an environmental assessment is to look at a range of scenarios to investigate potential problems – and their solutions, including mitigation measures – before a project can be approved.  

Taseko Mines’ applications for judicial review were dismissed by the Federal Court on the basis that there was no breach of procedural fairness. On May 14, 2020 the Supreme Court dismissed Taseko Mines’ leave to appeal from the judgment of the Federal Court of Appeal without costs.  

While we understand that this case started under the prior Canadian Environmental Assessment Act the principles discussed in the case will assist in forming a new federal and provincial environmental assessment processes. One of the key principles discussed is that projects will not be allowed to proceed prior to an assessment as to whether and how the serious environmental risks can be managed and mitigated in the circumstances.

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