I have a 2009 chevy hhr I smell gas on the outside of it in the back bumper area

If it smells like raw gasoline then there must be a leak or bad seal for the fuel tank or fuel sending unit. This will require a hands-on inspection and I don't recommend you drive the car any longer. This can be very dangerous. Use this link to find a good shop near you. https://repairpal.com/repair-shops Alex