Why are they stopping the water spraying efforts at Fukushima?

[ReturnoftheDjedi]

Firefighters ended their 13-hour water spraying operation to cool the No.3 reactor at the stricken Fukushima Daiichi nuclear power plant at 03:40 AM on Sunday.
...
The unmanned operation was originally planned to continue for 7 hours. But the fire department extended it by more than 6 hours after a government taskforce asked that water be sprayed for as long as possible.

The firefighters sprayed nearly double the capacity of the spent fuel rod pool.

The fire department will discuss with the government taskforce whether to spray more water.

http://www3.nhk.or.jp/daily/english/20_01.html

Japan's Self-Defense Forces have finished spraying water to cool the storage pool for spent nuclear fuel in the No.4 reactor at the quake-hit Fukushima Daiichi power plant.

The operation started at 8:20 AM local time on Sunday and continued for more than an hour.

Using 11 fire trucks, including one borrowed from the US military in Japan, the workers sprayed 80 tons of water during the operation.

Employees of Tokyo Electric Power Company will try to repair equipment to supply outside electricity to the No.4 reactor.

Fire fighters of the Tokyo Fire Department are to start spraying water at the No.4 reactor at around 6 PM and continue spraying until Monday morning.

Cooling systems haven't worked since the initial March 11 quake, raising concern about leakage of radioactive materials.

http://www3.nhk.or.jp/daily/english/20_13.html

They only shot twice as much water as the #3 pool can hold and a large portion of that didn't make it in.

And they shot much less at the #4 pool which is the one that has been empty and has a hole in it.

If they were seeing radiation decreasing as a result of spraying,
why stop the Water?!?

There is also a plant worker being interviewed on CNN casting doubt on the transparency of TEPCO, especially regarding the #4 Pool.
The guy is worried that there is a big problem going on there.

[kristopher]

1. They have to do some work to hook up the electricity.

I've been taking a break from it today, but I tuned in to NHK for a few minutes and they were saying something to that effect

[ReturnoftheDjedi]

2. the electricity didn't work at the damaged reactors that they have already connected it to.

they couldn't get the pumps running.

why would it be any different at 3 and 4?

they have suffered just as much damage.

[somone]

3. Water and electricity don't mix

The water was shorting out what the electricians were trying to do - hooking up the power cables

[ReturnoftheDjedi]

4. they already reconnected elec. at 1 & 2 and nothing worked.

Why isn't keeping the water going more important than finding out whether some explosion-damaged electronics work?

[The_Casual_Observer]

5. Becase the whole thing is/has melted down & they won 't just say so.

[ReturnoftheDjedi]

6. that's what the employee being interviewed on CNN was implying about #4

[The_Casual_Observer]

7. That employee is the only one there willing to tell the truth then.

[ReturnoftheDjedi]

8. and apparently this was only the first effort at getting water to #4

#4 has the pool that we were told was dry. empty. days ago.

so they only shot an hour's worth of water at the pool that has been empty for days?????

something strange is going on.

[Urban Prairie]

9. Yeah, Reactor #4 is likely impossible to deal with other than

continuously spraying water on it, because the radiation being emitted from the damaged spent fuel pool means that it probably cannot be repaired. No one or group of people can get close to it, unless they could prefab something that could be used to fix the damage, and they might not, and likely do not know the true extent of the damage. So why would they stop spraying water on it? Hopefully it is not because they know that it isn't working. I read that these pools are typically over 25 ft. deep.

[highplainsdem]

10. They have to vent #3 - pressure is rising. Link to the news story I posted in LBN:

http://www.washingtonpost.com/business/nuclear-officials-prepare-to-vent-radioactive-gas-from-crippled-japanese-reactor/2011/03/18/ABWBIts_story.html