Long staunchly opposed to the solution-mining copper development on environmental grounds, the council relented in a move Taseko said signalled "a new beginning".

"Our expectation is that open and productive dialogue will result and that our future together is bright," Taseko president Stuart McDonald said in a statement.

The company has been operating a test facility at Florence for the past two years, adhering to environmental guidelines as stipulated in the current permits.

Over the past 10 years, the Town of Florence made numerous legal challenges against Florence Copper. According to the council, the basis of these matters was the town's desire "to protect its citizens and the drinking water aquifer for Florence".

It challenged the company on the grounds of a zoning dispute, disputed the Aquifer Protection Permit citing unproven and untested technology, and argued the Underground Injection Control Permit and Aquifer Exemption Permit issued initially by the federal Environmental Protection Agency in 1997 should be revisited given the changing landscape of the town and residential development closer to the Florence Copper project.

"Transitioning Florence Copper to commercial production, which includes expanding the current wellfield and SX/EW plant, will mean an average of 85 million pounds of copper per year for 20 years beginning in late 2022," said McDonald.

The mine is said to have a 20-year life with C1 cash costs averaging US$1.13/lb. Taseko said at $5,600 per ton of installed capacity, Florence Copper was one of the world's lowest capital intensity copper projects.

The $227 million project has an after-tax net present value of $680 million using a 7.5% discount rate, and produces an internal rate of return of 40%.

Florence Copper has reserves of 345Mt grading 0.36% copper, for 2.5Blb of the red metal.

Shares in Taseko (TSX:TKO) achieved a fresh 12-month high in Toronto on Wednesday at C1.84, capitalising the company at $494 million (US$390 million).