Centerra Gold Inc. said July 5 that throughput levels at the Mount Milligan copper mine in British Columbia may need to be reduced in the fourth quarter if it does not get approval to secure excess water for operations.

The company applied to amend the environmental assessment certificate for Mount Milligan to provide additional short term water sources through to 2020 and to initiate the development of a longer term water supply plan for subsequent years.

Under the amendment, Centerra is seeking approval for Mount Milligan to access additional water from groundwater wells and surface water sources at Philip Lake, Meadows Creek and Rainbow Creek.

The company noted that it plans to finish consultations with regulatory bodies and the indigenous groups to secure approval for the amendment by the fourth quarter, but "there can be no assurance that Mount Milligan's short and long term water needs will be satisfied."

Mount Milligan produced 6.1 million pounds of copper in the first quarter, compared to 12.6 million pounds in the year-ago first quarter. Full-year copper payable output from the mine is estimated between 47 million pounds and 52 million pounds.