Jonathan James is in full flow, reminiscing about his family’s history at the Port Talbot steelworks, when his composure suddenly breaks.

“Everyone worked in the steelworks from a young age,” the 42-year-old says, as his voice starts to crack with emotion. “I remember my father coming home from work on his Honda Link moped and rocking up in the smell with the smell of coke ovens on his clothes. It’s been a massive part of my life – growing up, as well as when I finally started working there.”

James is one of thousands of employees who face redundancy as Tata Steel plans to close its two blast furnaces by the end of the year and replace them with a more modern, less polluting electric furnace.

The closure of the Port Talbot plant in south Wales will send economic shockwaves through the region. Up to 2,800 people could lose their jobs as a direct result. Many others in the wider supply chain and community will be affected.

Speaking to the Guardian from the steelworks, the shadow Wales secretary, Jo Stevens, says the fallout could be on a par with what happened here in the 1980s.

“We were badly affected by that,” says Stevens, who grew up in north Wales. “It’s left an economic legacy, but also a health legacy – we’ve got an older, sicker population than many areas in the rest of the United Kingdom.

“Nothing came in its place for a very, very long time. And then what did come didn’t compensate for what had gone, and it didn’t deliver jobs at the kind of scale and the wages that we needed.”

After a period during which a series of Labour frontbenchers have gone out of their way to praise Margaret Thatcher, Stevens has a slightly different take on the former Conservative prime minister who oversaw the closure of much of the British steel industry.

“She pulled the rug from under our feet, and then put nothing back in its place,” Stevens says.

Tata says it has been forced to take drastic action because of the scale of its losses at Port Talbot, where the Indian-owned company says it is losing £1m a day.

Last week, Tata unexpectedly announced it was closing the last of the coke ovens, an area in which James’s father once worked. The oven was due to close by the end of the year, but the company decided to shut it early because of safety concerns.

Gazing across a stretch of water at the imposing silhouette of the coke oven where work stopped less than a day earlier, Tim Rutter, a company spokesperson, insists the decision was the correct one.

“It was the right decision to close it at this time,” he says. “It was sad, though, for people who worked there all their lives – and their fathers worked there and their grandfathers worked there. There were lots of youngsters in there, and it’s an iconic part of the steel industry.”

The workers, however, are feeling less sanguine. They believe that the closure of the coke oven could accelerate the end of the blast furnaces, too, if Tata struggles to source its raw materials from abroad as planned.

They are also bitterly angry about the way in which they say the news about the oven was communicated to them, with several finding out on social media before the company made an official announcement.

“It is despicable the way we found out,” says Adrian Morgan, one of those affected. “The company had made a video which it put on their website as if it was some kind of celebration of the decision. It was so bizarre.”

A company spokesperson says: “We do everything we possibly can to make sure our employees are the first to hear about changes in our business, and use a wide range of communications including face-to-face, online and printed briefs to reach people working on our sites.

“Inevitably, however, with our variety of shift-based working patterns and with a large proportion of employees working away from offices in an expansive physical environment, it can take a little time to reach everyone in the organisation.”

The company has just finished a 45-day consultation period with unions about how to proceed with redundancies, but has not yet announced its final plan.

Labour hopes it might yet change its mind and accept a union plan to keep one blast furnace open while it constructs the electric furnace. The party is promising the company a share of its £3bn clean steel fund if it comes to power as an incentive. “The cavalry is coming,” Stephen Kinnock, the local Labour MP, has said.

The company says the problem with the union plan is more than financial. The logistical and technical difficulties of running the steelworks while also building the electrical arc furnace at the same site mean the plans are not “feasible or affordable”, Tata has said.

For now, the workers at Port Talbot are in limbo, faced with the imminent threat of redundancy but unsure when or how the axe will fall.

“Until the coke oven closed, there was an element of ‘We are going to be OK,’” says Alan Coombs, another Port Talbot steelworker. “This is the first time we have thought we are not OK. I had a guy call me up after the announcement and ask, ‘Am I going to be homeless in June?’”