Sea life began washing up on April 6, 2016 near a steel plant being developed by Taiwan's Formosa Plastics in Ha Tinh province on the country's north central coast.

Within weeks, more than 200 km of coast had been sullied by the accidental release of chemicals including cyanide, phenols and iron hydroxide.

The recovery is slow and anger endures.

"Where we caught 10 fish in the past, now we will only catch one or two," Hoa said.

Locals say thousands of fishermen have simply given up and gone to look for work elsewhere. Tourists are wary of beaches that have lost their pristine reputation and businesses are struggling.

But the wider impact could be even greater after protests over the spill encouraged a wave of activism that has pushed environmental issues up the agenda for a communist government that now promises greater scrutiny of investments.

"First, people were angry with Formosa for polluting Vietnam's environment," said priest and activist Dang Huu Nam.

"Now, they are angry with the unclear responses and solutions of some provincial authorities over fixing the disaster."

More than 40,000 jobs were directly affected in four provinces dependent on fishing and tourism. Across the country, a quarter of a million workers felt the impact, according to the labour ministry.

After months of rallies and an outpouring of anger not seen in four decades of Communist Party rule, Formosa agreed to pay $US500 million in compensation.

The Hanoi government and the provinces have now declared the sea clean and the seafood safe. But fishermen say fish stocks have yet to recover.

On a beach in Ha Tinh province, Hoa and two other fishermen's catch for the day was barely enough to fill a bucket. Compensation payments of 17.4 million dong ($US765) would not last them long, they said.

Despite the reduced supply, merchants say fish prices are now a quarter of what they were because of fears of continued contamination.

Many fishermen have simply abandoned their boats.

"It will take a long time to recover completely," Nguyen Truong Khoa, deputy director of the local environment department in the province, south of Ha Tinh.

Tourists are also still wary of this stretch of coast.

Once bustling, the Ky Hoa seafood restaurant on the central beach of Cua Viet is empty. Dust settles on chairs and tables.

"It's like the place is dying," said owner Mai Ngoc Ky.

The central government says half the compensation money has been paid out, but many complain about the wait.

"If things continue like this we will soon be bankrupt," said seafood trader Nguyen Viet Long.

The government says the steel plant has now addressed 51 out of 53 violations identified in an investigation into the accident, but it will only restart when it can do so safely.

Formosa hopes to get approval for trial runs soon, with the aim of starting commercial steel production by the end of the year, nearly a year behind schedule.

"We remember the lessons we've learned, and we're moving forward," said Chang Fu-ning, an executive vice president of the company.

Formosa has promised to invest another $US350 million at the mill, including in a more modern 'dry' coking system which does not use water as a coolant but is more expensive.

Formosa's use of the 'wet' coking system, which generates more waste, was highlighted as one of the failures in the government report. The company said it was still using the dirtier process, but it had until 2019 to switch.

Formosa wants to make the steel mill the biggest of its kind in Southeast Asia, exactly the sort of investment the government seeks so as to maintain annual growth rates of over 6 per cent.

But the activist movement roused by the spill has made Vietnamese - and the government - more attuned to environmental risks.

In February, the government said it would not grant licenses to any projects with a high pollution risk. Deputy Prime Minister Trinh Dinh Dung asked the environment ministry to revise rules and to intensify inspection and supervision of projects at the investment and construction stage.

Reuters - April 18, 2017