Also, given TEPCO's unfortunate habit of dribbling bad news out late...I am looking at that last sentence in the article once or twice and wondering what it might eventually be revealed to mean. (crosses fingers - please let it not be another 'oh we forgot to tell you but....")
A gal is a derived unit used physics and gravimetry. It is 1 cm/s^2.
Sorry, forgot to add:
So from the use of a unit of acceleration, what they’re talking about is the vertical design parameters for acceleration of the plant (or some aspect of the plant) in an upward direction. The plant will have design parameters for acceleration in horizontal and vertical directions that the structure(s) are supposed to withstand without breaking or failing.
What this amounts to is that the quakes they’re experiencing are exceeding the design parameters of their nuclear plants. This is sort of an obvious factoid by now, but the addition of numbers and units is interesting.
And WRT to the Onagawa plant’s status:
http://www.nisa.meti.go.jp/english/files/en20110414-1.pdf
It appears that they had a couple of the blowout panels on the upper part of the reactor building deformed and they lost some of their off-site power. The power feed is now redundant again, it was down to one off-site feed being left after last Friday’s quake.