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Japan tries desperate new measures at nuclear plant

Water is dropped by helicopter in an effort to avert full-scale meltdowns. U.S. expresses concern about 'very significant radiation levels' and tells Americans to stay 50 miles away.

March 17, 2011|By Mark Magnier, Laura King and Kenji Hall, Los Angeles Times
  • In this TV image, a Japanese military helicopter dumps water on the No. 3 unit of the Fukushima Daiichi nuclear power plant.
In this TV image, a Japanese military helicopter dumps water on the No. 3… (Associated Press )

Reporting from Sendai and Tokyo, Japan — Japanese authorities embarked on desperate new measures to avert full-scale meltdowns at a quake-battered nuclear plant Thursday, dispatching helicopters to drop tons of water on the reactors and readying water cannons to cool a spent-fuel pool that an American official said was responsible for "very significant radiation levels."

At the same time, public anger mounted over the government's lagging efforts to provide relief for the survivors of last week's earthquake and tsunami.

U.S. and Japanese officials appeared to disagree on the magnitude of the nuclear crisis, as the White House recommended Wednesday that American citizens remain at least 50 miles away from the stricken plant, much farther than the 12-mile evacuation radius given by the Japanese government.

Photos: Earthquake and nuclear crisis in Japan

The plant's operator, Tokyo Electric Power Co., planned to use the water cannons, normally used for crowd control, to try to douse the overheated and possibly dry spent-fuel pool at the No. 4 reactor of the Fukushima Daiichi plant, about 150 miles north of Tokyo. Without cooling, the spent rods could emit dangerous levels of radiation. Japan's defense minister said the U.S. military also was sending pumps to help inject water into the reactors.

The power company was also racing to install a new power line to the plant. The failure of primary power systems and backup generators that were swamped by the tsunami six days earlier has contributed to the escalating crisis.

At midmorning, military helicopters began dumping water on two of the damaged reactors, but after four flybys, the operation was suspended, public broadcaster NHK reported, citing defense officials. A day earlier, gusting winds and high radiation levels also forced the military to scrap the water drops.

Confusion persisted as to what was actually happening inside the plant's six reactors.

Japan's Kyodo News service, citing government sources, reported that the U.S. military would deploy unmanned, high-altitude reconnaissance aircraft to take images of the building that houses the No. 4 reactor to determine the status of its spent-fuel pool.

Unquestionably, the situation is dire. The units housing the Nos. 1, 2 and 3 reactors have all been hit by explosions, and their radioactive cores have begun to at least partially melt down, authorities have acknowledged. Fires broke out for two days running in the building housing the No. 4 reactor, and temperatures have been rising in Nos. 5 and 6.

In Washington, Nuclear Regulatory Commission Chairman Gregory Jaczko said at a congressional hearing that all of the water had evaporated from the spent-fuel pool at the No. 4 reactor. Japanese officials contended Thursday that military spotters had confirmed from the air that there was still water in the pool.

Acting on Jaczko's advice, the White House made its recommendation that U.S. citizens keep 50 miles or more away.

Jaczko told lawmakers that the 50-mile evacuation radius was based largely on concerns about the spent-fuel pool, which is believed to be seriously damaged and responsible for "very significant radiation levels likely around the site." The pool, which contains an estimated 125 tons of uranium fuel pellets, is not enclosed in a containment vessel, and if the pellets start burning, radiation will escape directly into the environment.

If the backup efforts to cool the reactors were to fail, "it would be very difficult for the emergency workers to get near the reactors. The doses they could experience would potentially be lethal doses in a very short period of time," Jaczko said. "That is a very significant development."

The nuclear crisis is vastly complicating quake relief efforts as well as search-and-rescue operations, including those involving the American military. U.S. forces in Japan were also observing a 50-mile no-go zone around the damaged plant. Pentagon spokesman Col. Dave Lapan described the prohibition as a precaution and said exceptions could be made with authorization.

Inside the crippled plant, emergency workers, wearing protective gear and doing short shifts to limit their radiation exposure, have been pumping seawater into the reactors to try to cool them. The work is hard and perilous and, among many Japanese, the workers have taken on the status of folk heroes.

"They're our last line of defense, and they are in there trying to control the situation … a really, really dangerous situation," said Kazuo Enomoto, who grows vegetables outside Tokyo.

Authorities have raised the maximum radiation dose allowed for the workers in an effort to avoid having to abruptly order them to abandon their posts, as happened Wednesday. About 180 workers were back at the site Thursday.

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