The St. Bernard Parish firefighters are leaving, as they don't think that their trucks are gonna survive if they stay. They're going to redeploy, and return as soon as possible afterward.
For you people that aren't familiar with LA, "parishes" are what you call counties. St. Bernard parish is the eastern part of New Orleans, one of the lower lying parts of the city, and one of the hardest hit by Katrina. It was 99% flooded.
Orleans Parish is the older and higher part of the city - what most of you saw if you've visited. The French Quarter, Garden District, etc. Katrina got 80% of it.
The first fire station just re-opened in St. Bernard a few months ago.