Jason, fellow APUG members;
The fact is that we are making a mountain out of a molehill which is film and print washing which in the grand scheme of things is quite small in impact on the environment.
So, to make On Topic points.... Hypo is used by people in their swimming pools as is Sulfite in order to control Chlorine. All of these are used in film manufacture or processing. Human beings produce Hydroquinones, Qinones, Catechols and other related developing agents as metabolic byproducts, and Tylenol is a developing agent itself passed through the body in some amount as a substituded p-Amino Phenol. We use Acetic Acid in pickles and on salads and Sulfite is used in grocery stores and restaurants on produce. Ascorbic Acid is used world wide as an antioxidant. And, due to pill consumption, the normal household sewage contains enough excreted drugs and their metabolic products to beggar the imagination!
So, what is "friendly"? Friendly is no waste at all! Can we afford it? Well, yes and no. Bill Gates could. I can't. So from that POV, if I follow my municipal guidelines which allow me to wash film and dump an occasional tank or tray of process solutions, they have judged what is environmentally good and I am doing what is environmentally acceptable.
In other posts, I have described how the method of wash varies the way the solutions reach the sewage plant. Which is better? The one that works for you and does not break local laws. But, so far, no one has come up with a real definition of friendly and unfriendly! All we can do is discuss relative merits of successive dumps or continuous flow of wash water when the real problem is that dumping the spent developer and fixer is the problem. The wash water contains such a small trace of chemistry that there is no real problem here.
In the final analysis, production of stable negatives and prints is the goal. Test them for retained Silver and Hypo. If they meet the accepted standards, then they are ok. If not, the method of washing is bad. Don't worry about the wash water, worry about disposal of the solutions used for processing. If the method used meets your local standard then you are OK. As for water consumption, that depends on where you live. Again, if you can afford it or if it meets local standards, then you are ok.