The Porgera gold mine in Papua New Guinea’s Enga Province is a world class gold mine but, as Executive Director for Barrick (Niugini) Ila Temu explains, it is also one of the world’s most difficult mines to operate.

Porgera gold mine. Credit: Barrick

Drainage, breakdowns in the infrastructure and illegal mining are the three challenges Porgera miners and executives face.

But the rewards are also great. Despite the severe obstacles, Porgera’s production in 2017 was about 500,000 ounces of gold and 204,000 in 2018 (with production affected by the Highlands earthquake).

Barrick Gold Corporation’s new President and CEO, Mark Bristow, explained during his recent trip to Papua New Guinea that the future of the Porgera mine is considered promising.

‘When you look at the current plans of Porgera, it has the potential to be able to deliver 500,000 ounces [per annum] for the next 10 years,’ he reportedly said.

‘The geologists are indicating that there’s potential for another 10 years after that.’

Barrick (Niugini) Executive Director Ila Temu says the company moves 65,000 tonnes of earth per day, 55,000 tonnes of which is waste.

‘Porgera has the potential to be able to deliver 500,000 ounces for the next 10 years.’

Grading in the open pit is about 2.6 grams per tonne and about 1.8 grams per tonne in the long term stock piles.

‘The underground gold grade is slightly higher: 6.8 grams per tonne.’

Infrastructure

Barrick Niugini’s Ila Temu Credit: BAI

Porgera is located at the end of the Highlands Highway, which means it is vulnerable to landslips and tribal conflict taking out power lines.‘So we become a mud moving operation rather than a mining company.

Temu says in 2016 the highway was closed for 101 days, and 54 days in 2017.

‘When you are on the end of the supply chain, you have to think pretty quickly about what to do.

‘That impacts on our ability to operate but with partnership we can get over these issues.

‘So we become a mud moving operation rather than a mining company.’

‘As if that was not enough we were also impacted by the [2018] earthquake.

‘The power station at Hides was knocked out. [We lost] generators, transformers—and the control room was turned upside down.

‘The gas pipeline that feeds us the gas was also shifted a few metres.

‘So, it was a significant impact. We went to mobile diesel power and got generators from Lae.’

Rainfall

River sampling. Credit: Porgera Joint Venture

Temu says whenever there is heavy rainfall, a large volume of mud comes into the mine.

‘If you don’t have a good dewatering system you have to stop operations to try to get that water out.’

In 2016, the mine had a ‘significant mud rush into the pit and the underground’ and later that year a sink hole failure.

In March 2017, rain caused a collapse in the west wall of the mine.

‘We budget for about 200,000 tonnes of mud per year. When the rainfall increases, that number increases four- or five-fold.

‘So we become a mud moving operation rather than a mining company.

‘It is good to have shareholders with deep pockets to come in and help us resolve these issues pretty quickly.’

Illegal miners

Illegal miners trespassing on the mine is a problem that Porgera has faced ‘since day one’. It is mainly a safety issue but it also has a business impact.

‘Over the years, most of the illegal miners have been non-Porgerans.

‘In 2018, on average, about 500 illegal miners were on the floor of the pit in the mine each day.’

‘They are young, male, have plenty of energy and plenty of time on their hands—and they need some cash.

‘Porgera, having free gold, becomes an easy target.’

Temu says in 2018, on average, about 500 illegal miners were on the floor of the pit in the mine each day.

If the number of illegals is bigger, the mine stops operating.

‘We move our people away until we clear the situation.

‘This impacts us every day in hours lost in production—because of their presence.

‘Earlier this year there were, for the first time, firearms in the pit. The illegal miners were fighting each other.’