We have given you advice that suits the hobbiest. To make what your doing 'legal' for business is an entirely different matter.
I would consult a book on lab safety about the best ways to store chemicals, ie locked cabinets, seperate oxidizers, things like that.
I would seriously consider finding someone who takes wastewater instead of dumping down the drain. Figuring out what you can do legally is probably not worth the hassle.
Originally Posted by Neil Poulsen