My protagonist is being pursued, and they have put a tracker in his arm he cannot remove, lest it blow up and kill him. Pretty standard stuff. It's the future, so maybe the tracker is more sophisticated, but I assume in the end it's still some sort of radio signal. The bad guy has the receiver.
At some point, hero goes to a secret place inside a mountain. He's deep in the caverns, and high up.
Will being inside that mountain block the receiver from knowing where he is?
EDIT: There's just one receiver, one tracker device sending the signal. They really just need to find him either in town or in a wide open area like a desert.