Members of the E tū union will strike for two hours on four separate days this week at Rio Tinto’s aluminium smelter — today, Wednesday, Friday and Sunday.
Smelter owner Rio Tinto said it believed the current terms and conditions offered were competitive.
E tū director Mat Danaher said the issue was not about money but workers wanting to have a collective employment agreement.
"It’s the principle of the thing. They haven’t actually had one since pre-1991. Everyone’s been on individual employment agreements," he said.
Bargaining had been going on for two and a-half years and union members felt like the employer was just going through the motions.
"The members obviously did start bargaining, submitting a kind of wish list for a perfect collective employment agreement. And during bargaining, most of that has been given up."
He accused Rio Tinto of wanting to individually set people’s wages as it saw fit and not have to bargain with them collectively.
"So this industrial action is about the members saying, ‘hey, actually, we’re New Zealanders. We’re not going to let you treat us like this. It’s about time you come to the table and sign off on a very modest collective employment agreement’."
Mediation had been set for May 20, which both sides were committed to, Mr Danaher said.
The union has 186 members at the site with about 800 workers all up working on the site.
He said Rio Tinto was a hugely profitable global company. It reported a profit after tax of $US10 billion ($NZ18 billion) for last year.
Some of the striking workers would be picketing the site during the stoppages.
Mr Danaher said there had not been a strike at Tiwai since the Employment Contracts Act came into effect in May 1991.
A Rio Tinto spokesperson said, in a statement, the company believed the current terms and conditions offered were competitive, both in the Southland and wider New Zealand market.
"In a tough economic environment for many businesses, we’re proud to continue to offer our team members and those looking to join our team market-leading benefits and we will continue to do so as part of Tiwai continuing to be a great place to work."
Safety and environmental stewardship, and stability of its operations and its local communities were the priorities for the company, the spokesperson said.
In a previous statement, the company said it was proud to offer market-leading benefits, which included a 10% company super contribution, on-target earnings for a rostered operator of $90,000 a year, a comprehensive medical scheme for staff and family members, a staff bonus scheme and great discounts in the community.
