Here are the code descriptions
P0441 = evap emission control purge fault
P0442 = evap emission control leak
P0446 = evap emission control vent circuit malfunction
I would first inspect all vacuum hoses in the engine bay very closely, for loose hose ends and cracks or dryrotting. Check the vac and wiring connections by the air filter box especially. Many shops can perform a Smoke Machine test, where they feed harmless smoke into the vacuum system and any leaks would be easier to spot, when you can see the smoke escaping.
Oh and when you fill up the tank, dont' overfill it. Stop at the first click of the pump gun. Overfilling may interfere with the tank vapor collection system (which is reporting a problem in your case).