You live in a huge city. They must have a public hazardous waste collection program like we have here in L.A. Check with your government's (probably city, but possibly county) sanitation bureau.
The fact that these are NOS chemicals makes things easier on everyone, and makes them less hazardous. They are not loaded with silver, and they are already appropriately labeled. It really could not get any easier for the hazmat facilities.
I recently disposed of about 30 liters worth of NOS Ilfochrome chemistry that was given to me. I kept it for about two years, but every kit was missing one component of the developer, and the bleach powder was liquefying and starting to burn through the metal bags. I decided it all had to go, so I took it all down there. It was free and easy.
It's a great opportunity to take all your other waste while you are at it. Paint, batteries, rags, solvents, auto fluids, electronic waste, etc.
Here, it is illegal to take in more than 15 gallons or 125 pounds of hazardous waste at a time, so you may need to make a few trips if the law is similar in Chicago.
(Here is an example of L.A.'s program:
http://www.lacitysan.org/solid_resources/special/hhw/safe_centers/index.htm.)