I had some driveway ice melt that was left over from the winter that I had poured from the spreader into an old metal popcorn tin. That tin sat in my garage for several months until I discovered it the other day. The snow melt had turned from beads to a clear thick liquid that isn't evaporating. Now, what can I do with this liquid? Can I pour it on the lawn? Pour it into the street? Pour it down the sink (I'm on a septic system). I don't want to kill anything, but I don't want it sitting around in a metal tin that's beginning to rust. I still have a bag of the stuff so I can look and see what it's made from. Thanks.