Howzit Johny, As long as the resin is in a liquid state you can't dispose of it legally. Don't know why he told you not to catalyze it since that's what I do with old resin past it usage time. Just don't add a lot of catalyst ( miight start a fire which could lead to an explosion in the can. I did just that about a week ago. Aloha,Kokua
Kakua is right just mix up a batch good and hot kick it off and throw it in the trash. Do the same think with your epoxy resin, once it is kicked it is not considered haz waste. For your empty containers just drain as much of the liquid from them punch a hole in them and dump them in the trash also.
Get a 5 gal bucket and fill it with kitty litter. Dump whatever you have left that’s liquid in there. At the end of the day, lift out the clumped-up resin and throw it in the trash. Don’t leave partially filled containers with either poly or epoxy to sit and smoke, you don’t need those fumes added to what’s curing on the board.