Fukushima Daiichi Unit 2 - Suppression Pool Outside Primary Containment Vessel

WNN has explained that the suppression pool or torus, which has been reported damaged at Unit 2, in Mark 1 reactors like the one at Fukushima Daiichi, sits in the centre of the reactor building at a lower level than the reactor.  The torus is not within the primary containment structure surrounding the reactor vessel, but within the secondary containment structure of the reactor building itself.

But there is another concern that because the water being pumped in is disappearing faster than it would if it only were caused by evaporation,  it is speculated that there may be a leak in the reactor's containment vessel, or it could be that there is so much pressure inside the reactor that it is hard to pump in water.

Comments

[Pat]

The torus (wet well) is part of primary containment (dry well + wet well + reactor pressure vessel). Secondary containment is the concrete structure that surrounds the dry (pear-shaped) and wet (torus) wells.