TORONTO (miningweekly.com) – Midtier copper miner Taseko Mines has started a federal judicial review that would seek to set aside certain findings of a federal review panel report on the environmental assessment for the proposed New Prosperity gold/copper project, in British Columbia.

Taseko had asked the court for a declaration that certain panel findings relating to seepage and water quality be set aside, and that the panel failed in certain respects to comply with principles of procedural fairness.

The judicial review would address the question of whether Natural Resources Canada (NRCan) – and, in turn, the panel – made a fundamental error when determining expected seepage rates from the tailings storage facility.

Taseko believed the evidence was clear that NRCan had failed to account for a liner that would be part of the tailings storage facility, thus modelling the wrong project design and assuming water would seep into open ground.

The Canadian Environmental Assessment Agency requested Taseko’s response to several questions regarding this matter and the company had provided information, which the company had subsequently published.

“Taseko had no choice but to file this application in order to comply with a 30-day time limit. But we remain of the view that the federal government should allow the project to proceed to the next stage of detailed permit-level examination and if so, the judicial review would not need to proceed,” Taseko president and CEO Russell Hallbauer said.

The panel had early in November found that the company's revised plan for a copper/gold mine in British Columbia posed significant threats to the environment.

However, in a surprising twist to the permitting saga surrounding the proposed mine, lead consulting engineer Knight Piesold had earlier this month determined that it appeared that NRCan, and subsequently the federal review panel, had used the wrong design in their analysis of seepage rates from the tailings storage facility.

The panel found that the project was likely to have significant adverse effects in about 30 different areas, including human health, salmon habitat and wildlife – findings which were now being challenged.