PERTH (miningweekly.com) – Fatalities at the Ridgeway and Hidden Valley operations have impacted gold miner Newcrest Mining’s September quarter results, resulting in lower gold production and higher all-in sustaining costs (AISC).

Operations at the Ridgeway mine, in New South Wales, were suspended for 11 days, while the Hidden Valley operations, in Papua New Guinea (PNG), were suspended for 33 days, following the respective fatalities.

Newcrest MD and CEO Sandeep Biswas said a combination of higher levels of planned and unplanned maintenance at the Lihir operation, in PNG, also resulted in a reduction in milled tonnage from the mine during the quarter.

This resulted in group gold production for the three months declining to 583 745 oz, compared with the 673 542 oz produced in the previous quarter.

AISC rose to $791/oz, compared with the $762/oz reported in the three months to June.

During the quarter under review, the Cadia Valley operation delivered 157 963 oz of gold and 16 613 t of copper.

Newcrest said on Tuesday that production at Cadia Valley during the quarter had been adversely impacted by lower grades resulting from the anticipated reduction in head grades at Ridgeway, coupled with the increasing volume from Cadia East Panel Cave 2, which, as expected, delivered lower head grades at the start of the cave.

The Telfer mine, in Western Australia, delivered 111 169 oz of gold and 4 724 t of copper during the quarter, with production affected by a planned major mill shutdown and lower head grades. This was partially offset by increased recoveries.

At Lihir, Newcrest produced 190 579 oz of gold during the quarter under review, with Newcrest saying higher feed grade from both the ex-pit and the stockpile feed was offset by high maintenance activity.

The Gosowong mine, in Indonesia, delivered 72 253 oz of gold during the quarter, while Hidden Valley contributed a further 11 123 oz and the Bonikro mine, in Côte d’Ivoire, delivered 40 659 oz of gold.

Despite the lower production volumes in the September quarter, Newcrest has maintained its full 2016 production guidance of between 2.4-million and 2.6-million ounces of gold and between 80 000 t and 90 000 t of copper.