Last week, the Tokyo Electric Power Company (TEPCO) had a bit of a mishap at the Fukushima Daiichi nuclear power plant. Due to some valves left open by mistake, untreated water leaked from the filtering equipment. Talk about a costly oversight! 
TEPCO spilled the beans at a news conference on Thursday, explaining that of the 16 valves that needed closing, workers accidentally left 10 wide open. That's like leaving the front door unlocked—not ideal when dealing with nuclear materials! 
The leak happened on February 7, and TEPCO is now questioning the staff who were on duty at the time. They initially reported a leak of about 5.5 tonnes of water containing 22 billion becquerels of cesium-137 and other radioactive substances. Now, they've updated the numbers to 1.5 tonnes and approximately 6.6 billion becquerels. Still, that's more radioactive material than we'd like to see spilling out! 
Turns out, the operation manual didn't have clear instructions about closing those pesky valves. TEPCO has admitted this oversight and is promising to tighten up their procedures to prevent any future slip-ups. Better late than never, right? 
This incident serves as a reminder of the ongoing challenges at Fukushima and the importance of attention to detail when dealing with nuclear safety. Stay safe out there, folks! 
Reference(s):
TEPCO: Water leak at Fukushima power plant caused by open valves
cgtn.com
