Being a member of a local organic society, this is something that has concerned me as well. The best I've come up with so far is to use XTOL for dev (handy because I tend to push b/w film a lot, and this is a good dev for that) and Silvergrain Clearfix Alkaline Fixer which is supposed to be a bit less toxic, a bit less smelly, and so far I've found it to be rather fast.
A while back I looked at the MSDS for XTOL and it looks as if it's mostly harmless and biodegradable. The fixer, which you should reuse until spent, will have silver in it. That silver can in fact be a problem for municipal water facilities. If there are any shops in the area that process b/w film in-house, you might ask them if they run their spent fixer through cartridges to reclaim the silver. I happened to find a gal that does that not far from here, and gave her a ring. She was more than happy to "process" my gallon of spent fixer, but I haven't had a chance to get over there yet (a bit of a drive.)
Yes, you can call your local waste management people, but chances are they are not going to know anything about photo chemicals and which ones are OK and which ones are not. I called mine and they felt that everything is toxic waste and should be treated as such, without even looking at the MSDS sheets for the stuff I'm using. So I asked this gal if the city gave her a hard time about the stuff she was using. She said at first yes, but then insisted they take the time to actually study the stuff she was using and how she was reclaiming the silver. In the end they said what she was doing was OK. So that sounds reasonable to me.
If there's no other recourse, you might see if your city has a door-side toxic waste pickup. More and more cities are starting to do this.
