8 Avril 2013
April 8, 2013
Radiation monitors and other devices have repeatedly broken down. Human error remains a constant problem. And the troubles plaguing the Fukushima No. 1 nuclear plant reached farcical levels when a rat caused a blackout and subsequent work to prevent a recurrence led to another system failure.
Such problems continue because the plant’s operator, Tokyo Electric Power Co., is still using temporary equipment and makeshift facilities, such as power supply units critical to cooling the crippled reactors and spent fuel rods, two years after the nuclear crisis unfolded on March 11, 2011.
TEPCO has come up with countermeasures--but only after complications have arisen.
For example, TEPCO set up a headquarters on April 7 to deal with the latest problem: leaks of radioactive water from two underground tanks, including 120 tons from the No. 2 tank announced on April 5.
The headquarters is headed by President Naomi Hirose. The company said executives will be involved in planning countermeasures to deal with the leaks.
Reports of the leaks came on the heels of a large-scale blackout on March 18 that suspended cooling system operations for spent fuel storage pools and other facilities for a maximum of 29 hours at the plant.
The power outage occurred after a rat caused a short circuit at a temporary switchboard on a truck parked outdoors. The switchboard has been mounted there for about two years.
The cooling system for the spent fuel storage pool for the No. 3 reactor was also suspended on April 5 due to a short circuit caused by a worker installing wire mesh to keep rodents away from a different switchboard.
Devices to measure airborne radiation have repeatedly broken down at the plant.
A radiation meter at the main entrance malfunctioned on April 3, causing an alarm to ring. It was replaced, but the new one broke down only two days later.
Alps, a new system to decontaminate radioactive water, was suspended due to an operational error on April 4, only five days after a trial run began.
The system was scheduled to begin operating last autumn. But the starting date has been postponed because the durability of containers for storing high-radiation waste has been called into question.
Work to decommission the melted reactors, which is expected to take 40 years, has also made little progress.
Radiation levels remain high around the three reactors that experienced meltdowns, preventing workers from approaching them.
TEPCO has sent robots into the reactor buildings to investigate the conditions. Many of them failed to return.
Securing power sources and disposing of contaminated water are two of the most critical tasks to ensure safety during the decommissioning process.
But TEPCO has delayed replacing the temporary equipment and rickety facilities because it has underestimated the precarious conditions of the Fukushima No. 1 plant. Countermeasures are not being taken based on a long-term perspective.
A continuation of such problems could force TEPCO and the government to review the work program for decommissioning.