PET's a little confusing on the topic. My '77 has the pump under the tank. Thought they moved it back there a few years earlier.
The fuel pump on a later car shouldn't run with the ignition just switched on; the switch on the AFM needs to provide a circuit, which usually only happens when the plate moves off the rest - e.g. because the motor is turning over or running. Perhaps the switch is broken or disconnected? Or the relay jumpered?
As far as "loud" is concerned, they can be pretty darned noisy... I switched the original out for an 044 motorsport - and that sounded exactly the same. They sound - well, like a pump that's got a significant current rating and moves a lot of fuel at high pressure.
Maybe being located up front it's easier to hear in the cabin? Mine sounds like it's just behind the gauges
