Dismantling Fukushima reactors will take decades

Japanese expect it will take decades before the Fukushima Daiichi nuclear plant can be fully dismantled, according to a draft report. A temporary cover may limit some radiation leakage.

Tim Hornyak
Crave freelancer Tim Hornyak is the author of "Loving the Machine: The Art and Science of Japanese Robots." He has been writing about Japanese culture and technology for a decade. E-mail Tim.
Tim Hornyak
2 min read
This is part of the steel frame that will support a polyester fiber shroud for the unit 1 reactor at the Fukushima Daiichi nuclear plant. Tepco

Japan today marked four months since the March 11 earthquake and tsunamis that left more than 20,000 dead and missing, with nuclear officials predicting it will take decades to dismantle the crippled Fukushima Daiichi nuclear power plant.

Removal of melted nuclear fuel at the plant won't begin until 2021; the fuel is apparently now in a solidified state and presents extremely difficult technical challenges. Full dismantling, including demolishing the reactors, will take decades more and will only happen after radiation levels fall, Japanese media reported, quoting a draft report on the cleanup.

Compiled by operator Tokyo Electric Power Company (Tepco), the Nuclear and Industrial Safety Agency, and the Japan Atomic Energy Commission, the draft based the estimate on the aftermath of the 1979 Three Mile Island accident in Pennsylvania.

The Fukushima crisis is much more severe, and forced the evacuation of 80,000 people. In early June, Japanese nuclear officials doubled their estimate of the radiation released after March 11. The reevaluation followed the government's ranking of the event on par with the 1986 Chernobyl catastrophe.

Workers at the plant are still trying to bring the critical situation under control by January 2012. Decontaminated water is being used to cool the reactors ahead of efforts to achieve a cold shutdown.

Meanwhile, Tepco is constructing a massive steel frame to support a shroud of polyester fiber that will cover the unit 1 reactor, where a hydrogen blast severely damaged the walls and roof, to reduce the entry of rainwater. It may also help mitigate radiation leaks.

Remote-operated equipment will erect the 177-foot-tall structure. A larger concrete sarcophagus, similar to the one at Chernobyl, could be built in the future to cover several reactor buildings.

Speaking of remotes, robots continue to help with inspections and cleanup at Daiichi. Following reconnaissance by PackBot robots in April, Tepco recently fitted an iRobot Warrior with an industrial-strength vacuum cleaner to suck up radioactive dirt and other particles. Check it out in the vid below.

In the near term, the government is planning "stress tests" on other nuclear plants in an effort to shore up public support for nuclear power. The tests will take into account European Union standards and involve simulations of natural disasters and loss of electricity for cooling systems.

While Japan relies on atomic energy for a third of its electricity, the government faces an uphill battle. Public pressure led to the temporary shutdown of the Hamaoka nuclear plant, which is located on a major fault line southwest of Tokyo, and thousands of people rallied against nuclear power in June.