My bath drain, drains very slowly. It doesn't appear to be clogged with
hair and it drains into a septic tank. No other drain seems to have a
problem. However I was wondering if the way the previous owner routed the
drain lines might be the source of the issue.

http://photos.imageevent.com/eigenve...e/P9160042.JPG

Shows the drain. There are two obvious things that make me wonder. One, as
you can see there is a wierd PVC joint right above the transition to the
galvanized pipe - almost like they necked it down, you can see all the green
joint compound. The other is the absolute horizontal pipe that runs from
the tub drain to the PVC "T" junction. Could this be the source of my slow
drain? I presume the vertical PVC pipe section is for the tub overflow
drain - it doesn't go anywhere else and it isn't a vent so far as I can
tell.

A couple of questions, if I were to snake the tub drain, would the trap
cause problems
Second, if I were to redesign the tub drain, how do I deal with the sewer?
I presume that there is basically raw sewage all the way to the top of the
tub drain "U" trap. Should I crack out the NBC suit and call in the EPA or
are there alternatives to dealing with the sewer line?

BTW: I finally cleaned out the bulk of the spiders in that corner, as you
can see its relatively clean now. The webs back there made the opening
scenes of Raiders of the Lost Ark look like Martha Stewart dusting cobwebs.