Another report from Kyodo News this morning :
" Radiation readings around the troubled reactor of the Fukushima Daiichi nuclear plant fell slightly after the Self-Defense Forces discharged water in an attempt to cool an apparently overheating spent fuel pool, the Nuclear and Industrial Safety Agency said Friday.
The radiation reading came to 279.4 microsievert per hour at the point roughly 1 kilometer west of the No. 2 reactor at 5 a.m. Friday, compared with 292.2 microsievert per hour at 8:40 p.m. Thursday, shortly after the SDF discharged water from fire trucks, according to the agency.
In an unprecedented move, up to 64 tons of water was discharged by helicopters and fire trucks of the SDF as well as a water cannon truck of the Metropolitan Police Department into the pool at the No. 3 unit of Tokyo Electric Power Co.'s Fukushima plant Thursday.
The mission will continue Friday as park of the effort to avert any massive release of radioactive materials into the air from the pool, while efforts to restore the lost cooling function by bringing electricity back to the plant through outside power lines have accelerated, according to the government.
The spent fuel pools at the power station lost their cooling function after the quake and tsunami struck last Friday. It is also no longer possible to monitor the water level and temperature of the pools of the Nos. 1 to 4 units.
Among the six reactors at the Fukushima Daiichi Nuclear Power Station, the No. 1, No. 2 and No. 3 reactors that were operating at the time of the quake halted automatically, but their cores are believed to have partially melted as they lost their cooling functions after the quake."