The head of the International Atomic Energy Agency said Wednesday that Japan's plan to release radioactive water from the Fukushima Daiichi nuclear power plant into the environment meets global standards of practice in the industry.

The comment by IAEA Director General Rafael Grossi made during a tour of the facility that was devastated by a powerful earthquake and tsunami in 2011 comes amid strong opposition to the plan from local fishermen and neighboring South Korea.

"Whatever way forward must be based on a scientific process, a process which is based on a scientifically based and proven methodology," Grossi told reporters after the tour.

"It is obvious that any methodology can be criticized. What we are saying from a technical point of view is that this process is in line with international practice," he said.

(IAEA Director General Rafael Grossi (front))

This is a common way to release water at nuclear power plants across the globe, even when they are not in emergency situations, he said.

The government and Tokyo Electric Power Company Holdings Inc., the operator of the crippled complex at the time, are considering ways to safely dispose of the more than 1 million tons of water contaminated with radioactive materials after being used to cool the melted fuel cores at the plant that straddles the towns of Okuma and Futaba.

The water, which is increasing at a pace of about 170 tons a day, is being treated using an advanced liquid processing system, or ALPS, to remove most contaminants other than the relatively nontoxic tritium. The water is being stored in tanks on the facility's premises but space is expected to run out by summer 2022.

Methods being discussed include releasing the water into the Pacific Ocean and evaporating it, both of which the government says will have minimal effect on human health.

But local fishermen have voiced strong opposition to such plans for fear that Japanese consumers would shun seafood caught nearby. South Korea, which currently bans imports of seafood from the area, has also repeatedly voiced concern about the environmental impact.

Grossi, an Argentine diplomat who succeeded the late Yukiya Amano as IAEA director general in December, said the Vienna-based organization is prepared to help put the international community at ease.

(Photo taken in January 2019 shows tanks in which radioactively contaminated water is stored within the compounds of the crippled Fukushima Daiichi nuclear power plant.)

"What the IAEA can do, at the request of Japan, is to provide support, advice when the process starts. This can take different forms, for example, we can assist in the monitoring of the water previous to its controlled release into the environment," Grossi said.

"What this does is provide the public in general, be it in Tokyo, Seoul, Buenos Aires, or Washington, the assurance of what exactly is happening," he said.

In a speech to TEPCO employees at the plant, Grossi voiced appreciation for their hard work on the decommissioning process, which is scheduled to end 30 to 40 years after the disaster.

"It's a job of decommissioning but it's (also) a job of reconstruction," he said

The process has been marred by setbacks, with the extensive damage at the Nos. 1 to 3 reactors posing technical challenges.

TEPCO had planned to begin assessing the wreckage inside the No. 1 unit's containment vessel using a drone in the latter half of 2019, but the company said in January it had pushed back the survey due to a spike in radioactivity during the cutting of an entry point into the vessel.

Grossi, who is on a five-day trip to Japan, also met with Prime Minister Shinzo Abe and Foreign Minister Toshimitsu Motegi on Tuesday, and is slated to hold talks with Cabinet members including industry minister Hiroshi Kajiyama on Thursday.

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