Below is the recorded sprayings to the spent fuel pool of unit 4 (data from Tepco press releases). The intensity of topping the pool appears to have increased lately. Similar data regarding the other SFPs can be found at:
http://www.gyldengrisgaard.dk/fuku_docs/fuku_sfp_sprayings.html
SFP4:
Concrete pump 23 April 2011 12:30-?
Concrete pump 22 April 2011 17:52-23:53
Concrete pump 21 April 2011 17:14-21:20
Concrete pump 20 April 2011 17:08-20:31
Concrete pump 19 April 2011 10:17-11:35
Concrete pump 17 April 2011 17:39-21:22
Concrete pump 15 April 2011 14:30-18:29
Concrete pump 13 April 2011 00:30-06:57
Concrete pump 9 April 2011 17:07-19:24
Concrete pump 7 April 2011 18:23-19:40
Concrete pump 5 April 2011 17:35-18:22
Concrete pump 3 April 2011 17:14-22:16
Concrete pump 1 April 2011 08:28-14:14
Concrete pump 30 March 2011 14:04-18:33
Concrete pump 27 March 2011 16:55-19:25
Injection of seawater through FPCFS 25 March 2011 06:05-10:20
Concrete pump 25 March 2011 19:05-22:07
Concrete pump 24 March 2011 14:35-17:30
Concrete pump 23 March 2011 10:00-13:00
Concrete pump 22 March 2011 17:20-20:30
Water spray by the Self Defence Force 21 March 2011 06:37-08:41
Water spray by the Self Defence Force 20 March 2011 08:21-09:40
Water spray by the Self Defence Force 20 March 2011 18:45-19:45
Explosion at unit 4 15 March 2011 06:00 appr.
Temperature in pool is 84 C 14 March 2011 04:08