TONY EASTLEY: Just when some Japanese were beginning to think that they might have been over the worst of the radiation scare after the March quake and tsunami, authorities have been shocked to find record levels at the Fukushima Daiichi nuclear power plant.

North Asia correspondent Mark Willacy is 100 kilometres north of the plant.

Mark Willacy, good morning. This has caught authorities by surprise.

MARK WILLACY: Yes it certainly has, Tony. This reading is extremely high.

It's 10 sieverts per hour. Now, we'd usually be talking in micro sieverts or mili sieverts. This is a much higher level of detection and it's at 10 sieverts per hour.

Now that's, according to officials, would be fatal to any worker if they were exposed to that for any length of time and it's 2.5 times the previous record radiation levels that's been measured at Fukushima.

So things aren't looking as rosy as some in the government have been predicting.

TONY EASTLEY: Now what particular area of the plant was this taken in and Mark, who is exposed to these readings as it goes on?

MARK WILLACY: It was taken at a ventilation shaft between reactors number one and two. This is quite a tall shaft. It was detected by what they call a gamma-camera. So TEPCO then sent in three workers to double check this reading and they were exposed to at least four mili sieverts of radiation.

Now, that's nothing too dramatic compared to what we've seen in the past but they were at the base of this stack.

Now we understand that the readings could be even higher than 10 sieverts at the top of the stack. So TEPCO have still got a lot more measuring to do to try and find out an accurate reading, but what they do know is that it is a record radiation level and it could be even higher than they think.

TONY EASTLEY: Mark, I mentioned that you were about 100 kilometres away from the plant. How are people there reacting to news of this?

MARK WILLACY: I think it's just more of the same, Tony. It is headline news this morning out here where I am and it is causing a lot of discussion on breakfast TV programs, on the radio.

Like as usual, this is a very heavily populated area around Sendai, Ishinomaki areas hit by the tsunami. But they're also dealing, obviously, with this radioactive fall-out and there are millions and millions of people here. And I don't think there's every going to be a situation where those people can just pack up and leave.

They've got to live with it and they've got to learn and live with it and that's something that they seem to be doing.

TONY EASTLEY: North Asia correspondent Mark Willacy, who's about 100 kilometres north of that stricken plant.