TSX-listed Imperial Metals Corporation has advised of the British Columbia Environmental Assessment Office recommending approval for the Mount Polley tailings dam construction to a 987 m elevation, compared with a previously permitted 974 m elevation.

Imperial undertook consultation with First Nations in the area with regard to the environmental regulatory process for the tailings dam, with British Columbia's Mining and Critical Minerals Minister and Environment and Parks Minister having granted consent and permits for the endeavour.

The facility will provide storage of the tailings generated by the expanded mining planned for Mount Polley to 2034.

Meanwhile, the mine produced 3.3-million pounds of copper and 6 848 oz of gold in the second quarter of the year, which compares to 9.4-million pounds of copper and 11 061 oz having been produced in the same quarter last year.

Imperial explains lower-grade stockpile material delivered to the mill resulted in lower copper and gold grades being milled. By the fourth quarter this year higher-grade material from the mine's Phase 5 area should begin to be delivered to the mill and eliminate the need to process lower-grade stockpiles.

The company confirms that three initiatives are being undertaken to improve grades in the third quarter already. Production from the C2 pit, which contains relatively high-grade gold, was 800 000 t less than expected in the first half of the year and, based on the block model of the pit, that tonnage contains about 6 000 oz of recoverable gold.

The C2 mining was rescheduled to be delivered to the mill this summer as warmer, drier conditions make it easier to process. The high clay content made it challenging to process this ore during the winter and spring.

Additionally, Imperial says a small high-grade pit called Boundary that was planned to be mined at the end of Mount Polley's mine life is being developed this quarter to provide a small amount of higher grade feed to the mill sooner.

The mine remains on track to meet its full-year guidance.

Moreover, Imperial continues with exploration on the Huckleberry mine to test an extension of the Main zone to the south-west, and to test a molybdenum trend defined by historic blast holes in the Main zone pit. All drill holes completed so far, including 22 diamond drill holes early in the year, intersected copper, molybdenum, silver and gold mineralisation, the company affirms.