More troubles affect Fukushima nuclear plant

Tokyo Electric Power Company (Tepco) announced on Monday (October 7th) that one of the pumps that is used to cool the damaged reactors at the Fukushima nuclear power plant experienced a power failure, possibly due to human era. The news follows on from the announcement that another leak of highly radioactive groundwater also occurred at the site, which could have reached the ocean.

Since the earthquake and tsunami of 2011, the damaged nuclear power plant in Fukushima has experienced problem after problem. Earlier in the month the company announced that workers had miscalculated the amount of contaminated groundwater that was stored in one of the large tanks on the site. Around 430 litres of water was then spilled from the tank when it was tilted on uneven ground. The operator has said that this water may have reached the sea.

The most recent problem arose when a worker who was conducting a systems inspection pushed a button that turned off power to a number of systems in all four reactor buildings. Systems are in place to cool the damaged reactors following a series of hydrogen explosions and meltdowns that occurred after the the disasters in 2011. A backup pump was used to immediately continue the cooling process and avert any problems. 

Hundreds of tonnes of water are used each day to keep the reactors cool in an attempt to stop any further explosions created by reheating. This water then becomes highly radioactive and is stored in tanks on the site. However, a number of leaks from these tanks have highlighted that they may not be the most stable solution for the water, which can contain up to 200,000 becquerels per litre of strontium 90 and other radioactive isotopes. The legal limit for strontium 90 is only 30 becquerels per litre, highlighting how damaging the water in the storage tanks can be.