decline from 351.4 to 265 μSv/h, but it is unclear if the water spraying efforts were the cause of the decrease. Saturday, 19 March A second group of 100 Tokyo and 53 Osaka firefighters replaces the previous team. They use a vehicle that projects water from a height of 22 meters to cool spent nuclear fuel in the storage pool inside the reactor of unit 3. Water is sprayed into the reactor for a total of 7 hours during the day. TEPCO reports that the water was effective in lowering the temperature around the spent fuel rods to below 100 °C. Sunday, 20 March External power is reconnected to unit 2, but work continues to make the equipment operational. Repaired diesel generators at unit 6 provide power to restart the cooling on units 5 and 6, both of which are returned to cold shutdown and their fuel cooling ponds returned to normal operating temperatures. TEPCO announces that the pressure in reactor 3's containment vessel is rising, and that it might be necessary to vent air containing radioactive particles to relieve pressure, as reported by Japanese broadcaster NHK at 1:06. The operation is later aborted as TEPCO deems it unnecessary. While joining in a generally positive assessment of progress toward overall control, Japanese chief cabinet secretary Edano confirms, for the first time, that the heavily damaged and contaminated complex will be closed once the crisis is over. Monday, 21 March Ongoing repair work is interrupted by a recurrence of grey smoke from the south-east side of unit 3 (the general area of the spent-fuel pool) seen at 15:55 and dying down by 17:55. Employees are evacuated from unit 3, but no changes in radiation measurements or reactor status are seen. No work was going on at the time (such as restoring power) which might have accounted for the fire. White smoke, probably steam, is also seen coming from unit 2 at 18:22 JST, accompanied by a temporary rise in radiation levels. A new power line is laid to unit 4 and unit 5 is transferred to its own external power from a transmission line instead of sharing the unit 6 diesel generators. Officials learn that the crisis will not end with power recovery as the cooling pumps are damaged beyond repair and must be replaced. An emergency order was placed for new pumps for unit 2 which had suffered less damage