ALCOA says that it has restored the stability of the production process at the Portland Aluminium smelter – and for the first time has outlined the cost of doing so.

But there is no timeline yet on a restart.

The revelations came yesterday at the release of the multinational corporation’s earnings for the first three months of 2023.

Portland Aluminium was forced to slash production by20 per cent, to about 75 per cent of its capacity, in mid-March due to instability in the production of rodded anodes, necessary to covey electricity into smelting pots.

Part of one potline, about 68 pots, has been removed from production, just months after the restart of part of the other potline, which had been out of action since 2009.

Chief financial officer Molly Beerman said the Portland smelter’s curtailment was one of the few drags on the company’s financial result and was expected to cost US$5-10 million (A$7.4-$14.9 million).

Alcoa chief executive and president Roy Harvey said “we have restored stability at this site”.

As previously reported in the Observer, staff have been working round-the-clock to sort out the issues.

“While we have challenges we need to solve we are laser-focused on operational stability and consistent improvement and we are seeing progress,” said Mr Harvey, who thanked staff for the work they had done.

Ms Beerman said no decision had been made on a restart of the curtailed capacity.

Alcoa reported an increase in its overall profit excluding depreciation and special items to US$240 million (A$357 million), thanks largely to improved aluminium prices, bot Mr Harvey pointed to a factor weighing down the price of the metal, which has also been responsible for improved financial performance at Portland.

That was Russian aluminium, unwanted in much of the western world, sitting stockpiled in London Metals Exchange warehouses – the LME price is the benchmark for aluminium and many other metals.

The largely unsellable aluminium had increased to 53 per cent of such stock from five per cent before the invasion of Ukraine and “we expect that to increase”, Mr Harvey said.

“If this continues the LME price will be relegated to the price for unwanted Russian aluminium.

“We are strongly urging the LME that Russian metal be delisted as a saleable item.”

The US government placed a 200 per cent tariff on Russian aluminium in February, including products made with the metal, leading many manufacturers of aluminium products to ‘self-sanction’ and look for other sources.