For the second time since 2010, the Canadian government has blocked development of Taseko Mines Ltd.’s billion-dollar New Prosperity copper-gold mine in south-central British Columbia over environmental concerns. Ottawa federal officials, however, will allow the small Canadian miner to submit a new proposal; the decision hinged on a Q4 2013 independent review.

In his ruling, Environment Minister Leona Aglukkaq called the open-pit project “likely to cause significant adverse environmental effects that cannot be mitigated,” in a statement quoted by Reuters News. Nonetheless, Ottowa “will continue to make responsible resource development a priority and invites submission of another proposal,” he added.

A Taseko spokesman said his company was “terribly disappointed” while adding that it would continue pursuing the project. “This is not the end,” said Biran Battison. Taseko, he added, will spend the coming days reviewing how to proceed; currently it is pursuing an ongoing application citing errors in the review panel’s findings on water quality and mine seepage.

“We fundamentally disagree with the decision made by the government of Canada,” Battison told The Toronto Globe and Mail. “The project is too important to the people of British Columbia – the logic and common sense are overwhelming.”

Two years after Ottawa blocked the project in Q4 2010 after overruling British Columbia’s provincial government’s Q1 2010 approval, Taseko reapplied after revising its mine plan to address regulator concerns. But aboriginal groups and other opponents insisted indigenous groups’ rights would both be endangered, although most of the debate focused on Fish Lake, a tourism spot.

British Columbia Mines Minister Bill Bennett, also called the decision disappointing but understandable. “We are extremely disappointed,” he told The Globe and Mail. “This is a wonderful opportunity for the region – with literally hundreds of jobs at stake.”

New Prosperity has a measured and indicated resource of 5.3 billion copper lbs and 13.3 million gold oz, with an estimated 20-year plus mine life; Taseko expects it to create nearly 2,000 jobs and generate more than $1 billion in government revenue.

Taseko, based in Vancouver, also owns and operates the Gibraltar copper mine in British Columbia.