OSAKA -- Plans to restart the Monju prototype fast-breeder reactor in 2008 came under fire at a public symposium Sunday in Osaka, as opponents warned the trouble-prone plant faces natural and man-made dangers that make another, more serious accident far more likely.</PARAGRAPH> <PARAGRAPH>'Restarting Monju is a bad idea. It's been shut down for over a decade. Firing up a nuclear power facility after it's been idle for so long is unprecedented and extremely dangerous,' said panelist and Upper House member Masamichi Kondo of the Social Democratic Party.</PARAGRAPH> <PARAGRAPH>The symposium was sponsored by anti-Monju groups in the Kansai region.</PARAGRAPH> <PARAGRAPH>The Tsuruga, Fukui Prefecture-based reactor was closed in December 1995 following a sodium coolant leak and fire due to a broken temperature sensor. In the following months, officials tried to cover up the seriousness of the accident and other safety violations, angering not only antinuclear activists but many in the government, including Prime Minister Ryutaro Hashimoto, who joined the calls for reform of Monju's operations.</PARAGRAPH> <PARAGRAPH>Fukui citizens fought in the courts to keep the plant permanently idled, but in May 2005 the Supreme Court overturned a 2003 Nagoya High Court ruling that had invalidated the approval for Monju's operating license. The high court had agreed with the plaintiffs that Monju's safety assessment was flawed, but the Supreme Court disagreed.</PARAGRAPH> <PARAGRAPH>Hiroshi Hiroi of the Japan Atomic Energy Agency, which operates the plant, said Monju will give Japan a cheap and stable source of energy, and will even compliment efforts to switch to other forms of energy and help the environment.</PARAGRAPH> <PARAGRAPH>'I support nonfossil-fuel energy sources like solar and wind –

. But they remain both expensive and less than 100 percent reliable, and will continue to be for some time. You'll still need a backup energy source. With Monju, not only will Japan have such a source, but also one that will help the country reduce greenhouse gases caused by the burning of coal and gas," Hiroi said.

Last September, the agency began modification work to get the plant restarted. The work, expected to be completed in February, includes replacing temperature sensors in the secondary heat transfer system.

"By the end of August, about 80 percent of the work was complete, so we are on schedule," said Takehide Deshimaru, a JAEA official based in Tsuruga.

Many in the audience questioned whether the modification work would keep Monju safe in the event of a natural, as opposed to a man-made, disaster. Seven earthquake fault lines lie within 40 km of Monju. In 1948, a quake with a magnitude of 7.1 struck Fukui, killing more than 3,700 people.

Hiroaki Koide, a researcher at Kyoto University Research Reactor Institute, warned that nuclear power plant operators underestimated the potential earthquake dangers when they sought permits to build atomic plants, including Monju, in not only Fukui but also Niigata, Hokkaido and Kagoshima prefectures.