TOKYO (Reuters) - Following are main developments after a massive earthquake and tsunami devastated northeast Japan and crippled a nuclear power station, raising the risk of uncontrolled radiation.
- Engineers successfully attach a power cable to the outside of the damaged Fukushima Daiichi nuclear station in a first step to help cool reactors and stop the spread of radiation.
- Further cabling inside under way before an attempt to restart water pumps to cool overheated fuel rods. Engineers able to restart a diesel pump to cool reactor No. 5, plant operator says.
- Plant operator says once power is restored, the next stage will be to check equipment is working and not damaged before trying to crank up the coolers at reactor No. 2, followed by 1, 3 and 4.
- The U.N. atomic agency says conditions at the plant are grave but not deteriorating badly.
- If engineers are unable to cool the reactor, the last option would be entombing the plant with concrete and sand to prevent a catastrophic radiation leak, the method used at Chernobyl in Ukraine in 1986.
- Severity rating of the nuclear crisis raised to level 5 from 4 on the seven-level INES international scale, putting it on a par with the Three Mile Island accident in 1979, although some experts say it is more serious. Chernobyl was a 7 on that scale.
- No plans yet to expand the evacuation area beyond 30 km at this point. Japan's nuclear agency said the radiation level at the plant was as high as 20 millisieverts per hour. The limit for workers involved in emergencies was 100 millisieverts but it has been raised to 250 for workers handling the Fukushima incident.
- The head of the U.S. Nuclear Regulatory Commission, Gregory Jaczko, says it could take weeks to cool the reactors. About 300 workers, wearing masks, goggles and protective suits are toiling in the radioactive wreckage.
- Japanese PM Kan plans to sound out the opposition on joining a grand coalition to handle reconstruction policy following the earthquake and tsunami.
- A man pulled alive from the rubble of a house eight days after the quake in Miyagi prefecture, one of the hardest hit areas.
- Nearly 7,000 people have been confirmed killed in the quake and tsunami. Another 10,700 people are missing with many feared dead.
- The Japanese government plans to dedicate up to 10 trillion yen ($127 billion) in crisis lending to businesses to help them finance day-to-day operations and repair damage, Nikkei said.
(Tokyo bureau; Compiled by World Desk Asia)