April 17, 2024

From Safe Distance, U.S.-Japanese Team Draws Up Plan to Demolish Reactors

Yet it is not too soon for a team of engineers from Japan and the United States to begin working on the thorny task of how to dismantle the reactors, four of which are so badly damaged that the plant’s operator has said they will be scrapped.

Already, dozens of engineers from Toshiba, which helped build four of the Fukushima Daiichi reactors, have been joined by experts from the United States to prepare for the decommissioning work, a job so big that the planning needs to start even now, in parallel with the efforts to contain the crisis.

The team includes experts from Westinghouse, whose majority owner is Toshiba; the Shaw Power Group, a civil engineering firm; and the Babcock Wilcox Company, an energy technology and services company, one of whose specialties is the disposal of hazardous materials.

The plans to take apart the reactors are complicated not only by the volatility of the situation but also by the uncertainty about the reactors’ condition once they finally cool. No one has ever decommissioned four damaged reactors at one power plant, let alone reactors rocked by a powerful earthquake and swamped by a tsunami.

In fact, no Japanese nuclear power plant has ever been entirely decommissioned, which is one reason Westinghouse and Babcock Wilcox — companies that helped shut down the damaged reactor at Three Mile Island in Pennsylvania after the accident there in 1979 — have joined the effort.

Among myriad problems, the engineers must find ways to dispose of the fuel, remove reactors, demolish buildings, and clean up nearby land and water.

“Each of these problems is solvable and have been solved before,” said Hiroshi Sakamoto, a senior vice president at Toshiba America Nuclear Energy Corporation, who returned to Japan to lead the team. (It has dubbed itself “Mt. Fuji,” short for Management Support for Fukushima U.S. and Japan Initiative.)

“The situation is really the complexity and combination of factors,” he said.

While the team makes plans, 800 of Toshiba’s engineers are helping the Tokyo Electric Power Company, which operates the Fukushima Daiichi plant, with the more pressing problem of cooling the reactors and reducing the radioactivity there. About 250 engineers are stationed in Fukushima, and an additional 500 are working at Toshiba’s nuclear engineering center in Yokohama, Japan.

They are helping to re-establish electrical power to pumps and motors and to install power panels; draining contaminated water; and acquiring desalination equipment, underwater pumps and air purifiers to filter radioactive dust. Westinghouse has provided Tokyo Electric with boron, fuel, spare pumps and other supplies.

“We are taking a two-tier approach for Fukushima,” said Kiyoshi Okamura, chief of Toshiba’s nuclear business. “These efforts are mutually complementary.”

Because of the emergency, Toshiba’s engineers — those who are helping Tokyo Electric and those planning the decommissioning — are working without a formal contract. But the Japanese-American team submitted a proposal to Tokyo Electric on April 4 that lays out a long-term plan to remove and transfer spent fuel as part of a larger project.

Toshiba has not been told when a decision will be made on the proposal, which might ultimately be worth billions of dollars.

Westinghouse, Shaw and Babcock Wilcox were eager to help when it became apparent early on that the Fukushima reactors might have to be scrapped. But the crisis made it difficult for Tokyo Electric to respond. By joining hands with Toshiba, the American companies won instant credibility and found a conduit to reach the utility.

“It was chaos at the beginning, so it helps to have Toshiba” as a partner, said Jack Allen, the president of Westinghouse in Asia.

Two weeks ago, engineers from the American companies started arriving in Japan, where they were briefed about the situation. They moved into a war room at Toshiba’s headquarters that includes offices in a secure part of the building. The rooms are stuffed with desks, computers, whiteboards and dozens of engineers slumped over laptops.

One door is covered with business cards and a sheet that includes photographs of the engineers so that names can be more easily matched to faces. On the walls are aerial photographs and schematics of the Fukushima reactors, as well as charts and photographs from decommissioned reactors at Three Mile Island and the Maine Yankee nuclear power plant in Wiscasset, Me., which took eight years to shut down. Graphic illustrations of cranes and other equipment are taped to the walls.

A well-used coffee cart sits in the hallway. Soda cans and snacks share desk space with laptops. A mixture of Japanese and English fills the air.

Though it is still in its early days, the “Mt. Fuji” team has proposed installing devices around the Fukushima Daiichi plant to monitor radioactivity. It is weighing what machinery is needed, based on various scenarios, and will soon open an office in New York so that engineers there can take over when the team in Tokyo is asleep.

Most of all, the team is waiting for the engineers at Fukushima Daiichi to cool the reactors so it can begin work. “All things hinge,” said David J. Richardson, a president at Babcock Wilcox, “on having safe access.”

Article source: http://feeds.nytimes.com/click.phdo?i=bcd64e717a894d7e15703f6ead8d3d03

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