The total cost of decommissioning the stricken nuclear power plant at Fukushima and providing compensation to victims has nearly doubled, with a new estimate placing the cost at $250 billion.
Five and a half years after the nuclear disaster, the painstaking work of cleaning up the radioactive disaster zone is progressing very slowly.
Workers on the site have just finished a two-year project to remove a temporary building that was encasing the number 1 reactor.
The building was erected in the weeks after the disaster to prevent radioactive materials from escaping into the atmosphere.
The radioactive threat still exists, but the plant's operator TEPCO said it had taken extra precautions to prevent the leak of radioactive substances.
"We are relieved to have removed the cover, but this is only the first step," said Satoshi Sunayama, the head of the work crew at the stricken plant.
The next step is to begin removing the nuclear fuel and debris from the three reactor buildings on the site. But the problem is, nobody knows how that is going to happen.
The Government is putting its faith in Japanese technology — Prime Minister Shinzo Abe travelled to Fukushima on December 11 to visit a robotics company.
He wants the entire region to become a hub for robotics companies — some of which will work on robots specifically designed to remove the melted nuclear fuel from the reactor cores.
Lesser robots have already tried and failed
Remote-controlled robots have been sent into the reactor cores on reconnaissance missions to find out how much nuclear fuel is inside. But the radioactivity affected their wiring and they failed to return.
TEPCO can only guess at the size of the problem. It told the ABC that its most recent estimate of all of the melted fuel and debris in the three reactors at Fukushima is 880 tonnes.
Tom O'Sullivan is an expert on Japan's energy sector, and said the costs of the clean-up work would weigh down the Japanese economy for many years.
"This is a very significant burden for the Japanese economy to bear, we've been in a recession for almost two decades," he said.
He said ordinary Japanese people would be hit with increasingly large electricity bills.
"The cost of cleaning up the nuclear power plant is going to have to be paid by the Government, the taxpayers and the electric power ratepayers in Japan both at the retail level and the industrial level," he said.
"So we will see increases in the order of magnitude of 6 or 7 per cent to the Japanese public and to Japanese industry."
He said a Government buyout of the plant's operator TEPCO was also on the cards.
"The company itself that owns those reactors, TEPCO, has a book equity of $US20 billion, so something's going to have to be done to actually strengthen its balance sheet or to carve out those distressed assets through a government buyout or a government takeover."
Watch Rachel Mealey's report tonight on ABC TV's 7:00pm news.