TORONTO (miningweekly.com) – The Tsilhqot'in First Nation on Monday said it was disappointed at being forced to once again oppose base metals producer Taseko Mine’s proposed New Prosperity mine, in the Cariboo-Chilcotin region of British Columbia, imploring the federal government to listen to community members, scientists and the public who were condemning the proposal for what it sees as “an environmental and cultural disaster”.

The Conservative Stephen Harper-led government in November 2010 rejected the mine proposal based on what then-Environment Minister Jim Prentice, described as one of the most "scathing" independent panel reports ever written.

The report documented both significant environmental and cultural impacts, many of which the first panel noted could not be mitigated with an alternative option proposed by the company.

"We look forward to the opportunity to share with this new panel all the reasons that this new proposal is just as unacceptable as the last one, regardless of the name or spin thrown out there by this company," Xeni Gwet'in First Nation chief Roger William said.

The 30-day public hearing phase of the environmental assessment of the New Prosperity mine started on Monday.

Taseko president and CEO Russell Hallbauer said the project was aligned with the values, interests and expectations of Canadians, specifically those who call the Cariboo home. He said it would provide training and employment opportunities for local communities and enable members, particularly youth, to train and work where they live.

“New Prosperity is a rare opportunity. The public value and benefit generated by the construction and operation of New Prosperity can be measured in thousands of jobs and in billions of dollars in new tax revenues for government,” Hallbauer said.

He added that the C$1-million copper/gold project could be accomplished without significant risk to the environment.

Environmental concerns were centred on Fish Lake, also called Teztan Biny, with its population of rainbow trout.

“The mine plan is not experimental but rather founded on proven engineering and science, utilising operating procedures and equipment that are currently in use every day at mines in Canada, elsewhere in the world and right here in British Columbia at our Gibraltar mine,” Hallbauer said.

But William said New Prosperity was a “test case” to see if the government took its commitment to First Nations seriously, and whether the revamped environmental assessment would have any credibility going forward.

The First Nation held that the proposed mine was so low grade, at a time when even major mining companies were suffering extreme setbacks, that it created serious doubt that the company could deliver the environmental mitigations being proposed, like putting Fish Lake on “life support” and using “unproven and expensive” water treatment over the long term.

Vancouver-based Taseko is the 75%-owner and operator of the Gibraltar mine, the second-largest openpit copper/molybdenum mine in Canada. Taseko's New Prosperity project, which is currently in the environmental assessment process, is one of the largest undeveloped gold/copper porphyry deposits in the world, with a one-billion-tonne measured and indicated resource containing 5.3-billion pounds of copper and 13.3-million ounces of gold.

At metal prices of $1 000/oz of gold and $3.15/lb of copper, the project has a pretax net present value of C$3-billion and a 40% pre-tax internal rate of return.

Taseko’s shares on the TSX on Monday closed 5.29% higher at C$2.19 apiece.