Pssssst the level of radiation at Fukushima is now 18 times higher

[muriel_volestrangler]

133. No, it's the same leak

OP article (BBC), 1 September:
"Last week the plant's operator reported radioactive water had leaked from a storage tank into the ground.

It now says readings taken near the leaking tank on Saturday showed radiation was high enough to prove lethal within four hours of exposure."

Asahi Shimbun, August 28:
"The leakage of about 300 tons of highly radioactive water from a surface tank at the crippled Fukushima No. 1 nuclear power plant may have gone unnoticed for more than a month before it was discovered on Aug. 19, according to a spike in workers' beta-ray exposure levels."

20 Aug, The Guardian:
"Frantic efforts to contain radioactive leaks at the wrecked Fukushima Daiichi nuclear power plant have been dealt another blow after its operator said about 300 tonnes of highly contaminated water had seeped out of a storage tank at the site.

The leak is the worst such incident since the March 2011 meltdown and is separate from the contaminated water leaks, also of about 300 tonnes a day, reported recently."

After the press release you quote:

Further, we announced that a puddle of approx. 3mx3mx1cm was found outside of the drain valve of the dike. Other than this puddle, there was another puddle of approx. 50cmx6mx1cm found outside of the dike.

http://www.tepco.co.jp/en/press/corp-com/release/2013/1229861_5130.html

This is follow-up information regarding the water leak from a drain valve of a tank dike in the H4 area in Fukushima Daiichi NPS.

At 7:00 PM on August 19, we started collecting water in the tank dike. Water was pumped up with a temporary pump to a temporary tank, and absorbent was placed inside the dike. Water collected until around 11:00 PM on the same day is approx. 4 m3.

http://www.tepco.co.jp/en/press/corp-com/release/2013/1229867_5130.html

We found streaky traces of flows on the wall surface of a drainage channel located east of the H4 area tanks. In response, we measured surface dose equivalent rates at this location, and the maximum rate was 6.0mSv/h (γ and β rays (70μm dose equivalent rate)).

We will conduct a detailed investigation and evaluation concerning these traces since the above information seems to indicate the possibility that contaminated earth and sand, etc. may have flowed into the drainage channel.

When water leaking this time was found, no water was found flowing on the surface of the ground near the above drainage channel.

http://www.tepco.co.jp/en/press/corp-com/release/2013/1229936_5130.html

So, your '23 gallons' was just the first puddle found, and there's a lot more that indicates it could have flowed elsewhere. But there was 300 tonnes missing from the tank, and the radiation exposure of workers was higher in July, so it looks like it had been leaking for some time.