Do you want to actually have the silver pulled out and be paid for it? Or do you just want to safely and legally dispose of it for free?
I don't know of a local place to do the former; I have not looked into it.
If the latter, go to a S.A.F.E. Center. I go to the one by the Zoo. http://www.lacitysan.org/solid_resou...ters/index.htm
I also take in my toners, pyro developers, electronic waste (including BATTERIES), oil filters, empty paint and solvent cans, used rags, etc.
All that stuff on the right that they say they accept is stuff that really should not be sent to landfills. It should be processed properly in order to be disposed of.