[jpalumbo]

I have some barium chromate (approx. 3g) left over from some demonstrations that I need to dispose of. I have not found a good disposal method that takes care of both of them. Can anyone give me a good disposal method?

[Grundalizer]

Not a nice compound to dump in the ocean or in your backyard.  I've always wondered how amateur chemists dispose of their chemicals, but I've never read/heard/seen anything about it.  If I were you, although I can't imagine you'd have great luck, try taking it to a local high school or  college and asking them if you can pay for them to add it to their chemical waste bottles.  I know at my college we fill up all types of bottles with oxidizers/acids/bases/ organics/inorganics/everything else etc, and some company comes to take it away to incinerate it, but I'm guessing it is not cheap.  If it's only 3g and its a cool lab tech I'm sure they'll take it.  They might not take your word at face value though, you SAY its Barium chromate(and i believe you), and if its still yellow I'm sure you can convince them.  I know at my school if lab techs find an unlabelled bottle of anything and don't know what lab it is from, it has to go under "unknown waste" which is significantly more expensive to get rid of.  It does suck that disposing of chemical waste is not cheap (although I don't know actual prices)  but +1 karma for you for asking instead of just dumping it down the drain.

I can't think of any reaction to bring it back to a "harmless" chemical either 

[Fleaker]

Most municipalities have some sort of waste/recycling day where the populace can turn in old batteries, motor oil, sometimes television sets and a variety of other things. They often accept old mercury thermometers, sphygmomanometer, and even chemical waste. The more info you can provide, the better.

Your best bet is to call the hazmat safety officer of the university and find out if they can't take it off your hand. Bear in mind, that there are rules regarding the transport of hazmat materials. I think 3 g of barium chromate is really nothing to be worked up about, but it's also something that shouldn't go down the drain (despite its low solubility).

Barium is fairly toxic. You could dissolve it in concentrated HCl thus reducing the chromium to a less dangerous oxidation state. chromate is strong enough to oxidize the Cl^- to Cl₂. The BaCl₂ can be precipitated with sulfate, which is usually buried.