Tepco Confirms Meltdown of ReactorsBy Takeshi Awaji and Yuji...

Tepco Confirms Meltdown of Reactors
By Takeshi Awaji and Yuji Okada - May 24, 2011 5:51 AM GMT+0200
http://www.bloomberg.com/news/2011-05-24/tepco-confirms-meltdown-of-no-2-3-reactors-at-fukushima-1-.html

Tokyo Electric Power Co. confirmed a meltdown of fuel rods in two more reactors at its Fukushima nuclear plant, which has been emitting radiation since an earthquake and tsunami knocked out power and cooling systems.

Fuel rods in the No. 3 unit started melting on March 13 and those in the No. 2 reactor on March 14, Junichi Matsumoto, a spokesman at the company known as Tepco, told reporters in Tokyo today. The fuel dropped to the bottom of the pressure vessel after melting although the damage to the vessel is ?limited,? he said.

Tepco raised the possibility of more extensive damage than assumed at the reactors when it announced last week, more than two months after the disaster, that fuel rods in the No. 1 reactor had melted within 16 hours of the quake on March 11. Tepco?s analysis is catching up with U.S. assessments in early days of the crisis that indicated damage to the station was more severe than Japan officials suggested.

The meltdown of the cores is the ?greatest at the No. 1 reactor, followed by the No. 3 unit and then No. 2,? Matsumoto said. The analysis of the damage became possible ?after data from the central control room was retrieved,? he said.

Tepco has been struggling to cool reactors and spent fuel pools to stop radiation leaks and resolve the world?s worst nuclear crisis since Chernobyl in 1986.

Melting Fuel
The operator of the Fukushima Dai-Ichi plant said earlier it believes 35 percent of the rods of reactor No. 2 were damaged after cooling systems failed. About 30 percent of those in the No. 3 unit were damaged, it said.

Tepco fell rose as much as 2.4 percent today to 342 yen in Tokyo and traded at 335 yen at 11:00 a.m. The shares are down about 84 percent since the quake and tsunami struck.

The fuel rods in the No. 1 reactor started melting about four and a half hours after the magnitude-9 earthquake when the water level in the reactor core vessel fell below the base of the assembly, Tepco said last week.

Engineers established the extent of the damage after fixing gauges in the reactor No. 1 building. The building was damaged by a hydrogen explosion on March 12. Workers were sent into the No. 2 and 3 buildings last week to establish whether repairs could be carried out on gauges.

Tepco on April 17 set out a so-called road map to end the crisis in six to nine months. The utility said it expects to achieve a sustained drop in radiation levels at the plant within three months, followed by a cold shutdown, where core reactor temperatures fall below 100 degrees Celsius. It reiterated the timetable last week in an update of the plan.

To contact the reporters on this story: Takeshi Awaji in Tokyo at [email protected]; Yuji Okada in Tokyo at [email protected]