Tokyo Electric Power Co. suspended operations at the advanced radioactive water cleanup system at its crippled Fukushima No. 1 nuclear power plant Monday only some six hours after its resumption.
Tepco resumed operations at two units of the Advanced Liquid Processing System, or ALPS, around 1 p.m. But it suspended them shortly before 7 p.m. after it found drops of water at a tank set up to measure levels of radioactive substances in water processed by the system.
The amount of leaked water is estimated at about 0.5 liter and there are no water leaks outside the plant damaged in the March 2011 earthquake and tsunami, the company said.
Operations at all three ALPS units had been halted since March 18 due to a considerable decline in the ability of one of them to remove radioactive materials in contaminated water.
Tepco regards ALPS as a key facility to deal with contaminated water at the plant as it drastically reduces levels of 62 types of radioactive substances, such as strontium-90, although it cannot absorb tritium.