Old AvGas
The fuel supplier for our airport requires that fuel in storage tanks must be used (or added to) at a maximum of nine months intervals. They go through about a semi-trailer load per month so its not an issue. It is tested for water, particulates and API gravity often. I wouldn't use 8 year old Avgas in an airplane, period! Find the cheapest chainsaw, leaf blower, mower or similar you have to dispose of it through. I wouldn't even run it in a hot rod or dune buggy if it was that old.