More than four months after it was crippled by an earthquake-generated tsunami, Japan's Fukushima Daiichi nuclear power plant has stabilized and workers are on track to achieve a "cold shutdown" within six months, government and utility officials say.
Officials made a positive prognosis this week after scaling several hurdles in decommissioning the facility, which was damaged March 11 when the tsunami disabled the plant's cooling system. The flooding led to partial meltdowns of the reactors, which released radioactivity into the atmosphere and prompted the evacuation of tens of thousands of nearby residents.
In recent weeks, engineers have established an improvised cooling system to circulate water through the damaged reactors. They have also set up a system to decontaminate radioactive water from the process. Nitrogen injections at the four damaged reactors are helping to prevent more explosions, officials said this week.
But officials from Tokyo Electric Power Co., which runs the plant, warn that even if a cold shutdown — a stable state in which the reactor cores no longer burn off coolant water — is reached by early 2012, the final cleanup could take a decade or more. The plant will eventually be encased in concrete as a safety precaution.
"We still don't have a schedule for the work to decommission this plant, and that's planning that we have to do right now," Goshi Hosono, the minister handling the central government's response to the crisis, told reporters in Tokyo on Tuesday.
The latest update on the status at the plant comes as pressure continues for Prime Minister Naoto Kan to step down in light of his perceived poor handling of the crisis and lingering public health concerns.
In recent days, the Japanese media reported that more than 140 beef cattle suspected of being contaminated from ingesting straw laced with radioactive cesium had been shipped from the Fukushima region to consumers nationwide. Officials have since suspended all shipments of beef cattle from the area.
Cautious government officials say it will take several more months to determine whether 80,000 evacuated residents will be able to return to their homes. The Fukushima Daiichi plant is about 150 miles north of Tokyo.
"During the time that I've been involved in this effort, we've encountered every kind of difficulty, so I don't think we have room to be optimistic," Hosono said. He added that he hoped "we can achieve some specific results" in bringing back residents by year's end.