Water tainted with tritium, a radioactive form of hydrogen, is to be released into the Pacific Ocean, says the head of the company responsible for the Fukushima clean-up operation.

There are around 580 of barrels containing the radioactive water which was used to cool the nuclear plant's damaged reactors.

Local residents are furious at plans to release the radioactive tritium from the 2011 Fukushima nuclear plant, which suffered a triple meltdown, into the sea.

“The decision has already been made,” said Takashi Kawamura, chairman of the Tokyo Electric Power Company (TEPCO). Debate has raged over the disposal of almost 777,000 tons of waste containing tritium.

However, Tepco need to wait for the government’s final decision to release the water into the sea. “We cannot keep going if we do not have the support of the state,” Mr Kawamura said in a Japan Times report.

A supporter of releasing the water into the sea is Shunichi Tanaka, chairman of the Nuclear Regulation Authority. In the past, Tanaka has slated Tepco for their hesitant stance.

“An operator lacking the will to take the initiative does not have the right to resume operation of nuclear reactors,” he said.

Local fishermen are against the proposal of ocean release, fearing that the negative publicity will affect their livelihoods. “Releasing (tritium) into the sea will create a new wave of unfounded rumors, making our efforts all for naught,” said Kanji Tachiya, head of a local fishermen's cooperative.

Tritium is said to be of little danger to humans unless exposed to high quantities. According to NRA chairman Tanaka, the chemical is “so weak in its radioactivity it won’t penetrate plastic wrapping”.

Inside the twisted remains of Fukushima nuclear plant Show all 2 1 /2 Inside the twisted remains of Fukushima nuclear plant Inside the twisted remains of Fukushima nuclear plant 6-Fukushima-1-EPA.jpg The Fukushima nuclear power plant as seen by Tokyo Electric Power Company officials and journalists EPA Inside the twisted remains of Fukushima nuclear plant 6-Fukushima-2-EPA.jpg Tokyo Electric Power Company officials and journalists and journalists visited the site yesterday EPA

Simon Boxall, an oceanographer at the University of Southampton told the Guardian: “In the broad scale of things, if they do end up putting the material in the Pacific, it will have minimal effect on an ocean basin scale.”

Environmental activists fear that dumping the tritium-laced water into the ocean could become commonplace.

"They say that it will be safe because the ocean is large so it will be diluted, but that sets a precedent that can be copied, essentially permitting anyone to dump nuclear waste into our seas," Aileen Mioko-Smith of Green Action Japan said.