Tainted foodstuffs but also some good signs found in Japan nuke crisis+

TOKYO, March 19 Kyodo -
Excessive radiation was found Saturday in milk and spinach in Fukushima and Ibaraki prefectures, while officials spoke of some stability and lower-than-anticipated temperatures at crisis-hit reactors at the Fukushima Daiichi nuclear plant as anticrisis efforts continued.
The radiation was above Japan's regulated standards but does not immediately pose a risk to human health, Chief Cabinet Secretary Yukio Edano said in a press conference.
Edano said, however, that conditions at the plant's most dangerous No. 3 reactor unit have likely become relatively stable after firefighters threw some 60 tons of water at a boiling spent fuel pool there shortly after midnight from outside the damaged building housing it.
Defense Minister Toshimi Kitazawa separately said the surface temperatures at the No. 1 to No. 4 reactors were found in the morning at 100 C or lower by a Self-Defense Force helicopter, adding their conditions remain more stable than expected.
''We're trying to get things under control, but we're still in an unpredictable situation,'' Edano said.
Prime Minister Naoto Kan instructed the Defense Ministry to keep monitoring around the plant, Kitazawa said.
Plant operator Tokyo Electric Power Co., meanwhile, managed to connect power cables to the No. 1 and No. 2 reactor buildings, paving the way for checks of their equipment as early as Sunday to see if they can work.
Restoring a stable source of electricity to reactivate lost cooling systems is a key step to prevent further deterioration of the situation, particularly as the No. 2 reactor has suffered a rupture at its containment vessel's pressure-suppression chamber at the bottom.
At the No. 3 reactor, the Tokyo Fire Department's ''hyper rescue'' team began in the afternoon an unmanned operation of having its heavy fire trucks continue shooting a total of 1,260 tons of water at its spent fuel pool for seven hours, the department said.
After massive smoke was detected from the No. 3 reactor building on Wednesday, the Self-Defense Forces, firefighters and others have been engaged in an unprecedented mission to spray tons of water in an attempt to fill its pool with water, which is vital to prevent a release of radioactive substances.
A rise in water temperature, usually to 40 C, causes the water level to fall, thus exposing the spent nuclear fuel rods, which could then heat up further, melt and discharge highly radioactive materials in a worst-case scenario, experts say.
The SDF is now preparing to spray water into the No. 4 reactor to help cool its spent fuel pool as well, Edano said.
At the No. 5 and No. 6 reactors, it has become possible to cool spent fuel by circulating water in the storage pools, as one of emergency generators was restored early Saturday, leading the temperature to fall to 67.6 C from 68.8 C in four hours, said Tokyo Electric, or TEPCO.
Japan raised the severity level of the No. 1 to No. 3 reactors to 5 on an international scale Friday, the same level as the Three Mile Island accident in the United States in 1979, and the worst in the country where a 1999 criticality accident was given level 3.
The three reactors were the only ones operating among the plant's six reactors at the time of the magnitude 9.0 quake, and halted automatically, but their cores are believed to have partially melted as they lost cooling function after the quake and tsunami.
According to TEPCO, the maximum earthquake intensity measured at the No. 3 reactor building was 507 gals, smaller than 600 gals the nuclear plant is required to withstand, on a provisional basis. But the ensuing tsunami is believed to have damaged the cooling functions.
The No. 4 to No. 6 reactors were under maintenance at the time of the quake but their cooling functions also suffered, affecting their spent fuel pools.
The buildings housing the No. 1, No. 3 and No. 4 reactors have since been severely damaged by apparent hydrogen blasts, leaving fuel pools there no longer covered by roofs.
The government has set an exclusion zone covering areas within a 20-kilometer radius of the plant and has urged people within 20 to 30 km to stay indoors.