why does refueling a 2004 c70 take so long?

First, is the Check Engine Lamp on? If so, you may have a problem with the Evaporative control system, not allowing the tank to vent properly. This diverts the venting vapors back up the fuel filler neck and turns off the gas pump nozzle. If the check engine lamp is not on, there may be a problem with the roll-over valve in the fuel tank.