Mal Rowe's post of Dec 20 on the mercury arc thread concluded <I'm pretty sure that the only remaining operation mercury arc rectifiers are in museums>.
But it was only about this time last year that mercury arc rectifiers at the West Maribyrnong tramway substation were finally replaced by silicon recifiers. The mercury arc units were part of the WW II installation made necessary by extension of tram lines to serve the expanded operation of Commonwealth ordnance factories.
The silicon rectifier equipment was installed in a new purpose-designed building and as far as I know the decommisioned mercury arc rectifiers may well remain in situ in the old building.
The scenes of the West Maribyrnong mercury arc bulbs in actual operation that appear in the Footscray DVD were shot around July 2010.