Disposal of E6, C41 and B&W chemicals, self neutralizing?

[Shizam]

I've heard and read from 2nd hand sources on the web and at my camera shop that its ok to pour your processing chemicals down the drain (EXCEPT FIXER), that its 'self neutralizing'. I assume that means self neutralizing pH for acid/bases but what about the chemicals themselves? Is there anything actually published on the impact of pouring my chemicals down the drain?

Thanks

[Bob-D659]

What quantities, 100 gallons per day or per year? or go here http://www.foothilldisposal.com/resi...rdousWaste.htm for your local rules.

[Ian Grant]

Commercially you need a license to do this but yes that's the usual method of disposal, the fixer/bleach dix can also go downn the drain provided it's de-silvered to less than 1 ppm silver.

When I worked for a Bullion dealers I regularly worked alongside Photolabs advising on chemical disposal, we sold silver recovery units or offered a collection service. (Either way we recycled the Silver). Part of my job was liaising with the licensing authorities and I worked alongside the senior chemists etc they said there was normally no impact at all on water/sewage treatment plants from even quite large commercial labs, provided the silver was removed. They would be concerned if the water/sewage treatment plant was very small, it might not be able to cope with the effluent from a large lab, but this hadn't happened anywhere.

We had a license to dispose over 1000 gallons of treated fixer, bleach-fix, developer etc a day provided it was diluted and between certain pH limits.

In practice most UK minilabs produced a volume of effluent that fell well below the threshold for requiring a full license to discharge, and just needed a letter of consent to discharge, but that varied depending on the water authority.

There's a lot of ambiguity about disposal of chemicals from a home darkroom, but in general most authorities assume & accept that people discharge spent chemistry to the drain, the volumes are so minuscule and there are far worse effluents discharge regulary from every household.

Ian

[railwayman3]

I think I mentioned in another thread that I had a word with our local authority a few years ago regarding disposal of "hobby" photochemicals.

The guy obviously knew his chemistry, and he said that it was OK to put normal used photochemicals (he said "things like DIY kits from such as Kodak".) into the foul sewer (not the rainwater drains). My impression was that they were (as suggested above) no more significant than small quantities of stuff like household cleaners and bleaches.

He added that any "special" chemicals should obviously be considered separately, and any waste concentrate or powders should be taken to the local facility.

[AgX]

`Neutralizing´ with reference to waste can mean anything.
It can be aimed at the ph, the redox-power, the inactivation of certain unwanted chemicals by undergoing a forming reaction.

[Shizam]

Great,
Thanks for the extra info guys, and the link to foothill, I googled the crap out of it last night and couldn't find anybody to call. And yea, this is on the order of 2 gallons a month