The Ford Explorer Sport Trac doesn't have a single, readily accessible "emergency fuel shutoff" switch like some other vehicles. In the event of a fuel leak or fire, the best way to stop the flow of fuel is to disconnect the fuel pump's electrical connection. This requires accessing the fuel pump, usually located under the vehicle, and disconnecting its electrical connector.
However, this should only be attempted if you are trained and capable of safely doing so, and if you are confident that doing so will not make the situation worse. It's dangerous work involving fuel and electricity.
Your best course of action in a fuel-related emergency is to:
1. Evacuate the vehicle immediately. Get yourself and any passengers to a safe distance.
2. Call emergency services (911 or your local equivalent).
3. Do not attempt to work on the fuel system yourself unless you are a trained professional.
Trying to find and disable the fuel pump yourself could put you at significant risk. Let trained emergency personnel handle the situation.