Sounds more like a fuel pump failure. What are the conditions that you hear the whine? Engine running, key on, engine not running, car in motion, high or low engine RPM, front or rear of car, etc.?

When the engine is running. Wouldn't I see a leak with a fuel pump failure? I don't know. The pitch of the whine increases when I accelerate, and decreases to a lower tone when I decelerate. It's also apparent when idle. It seems as though the noise is coming from underneath the car in the middle near the rear.