Hi Jason,
If you assign each Impact pad to it's own output each pad will have a fader in the mixer to adjust it's level. If you move an Impact fader from one of it's multiple outputs and more than one sound changes level, that means more than one pad is assigned to that same output.
Impact has a total of 16 pads and 16 outputs, so every pad there can have it's own discreet mixer channel, but you have to assign the pad outputs to separate them fully that way.
Hope that helps.