Flying Binghi - apparently the plant in question had an earlier round of redundancies and closed 1/3 of its capacity a few months back, and is an old and inefficient plant that was racking up substantial losses that were forecast to continue. The losses were due to, among other things, a significant drop in world aluminium prices combined with the high Aussie dollar. If you have a look here
CLIMATE SPECTATOR: Abbott's furnace for carbon tax facts | Daniel Palmer | Commentary | Business Spectator
they discuss some of the reasons behind the plant closure ($6-$7 million/month in losses) and how the carbon tax isnt a significant factor. They aren't too complimentary of how it has been blamed on the carbon tax, and it looks to be another example of everything bad that happens being blamed on "the big bad carbon tax" by politicians keen to make hay while they can.