As long as the motors have internal thermal overload protection you may install them on the same circuit (assumes 2 x 2hp = 24amps, which is 80% of 30 amp breaker protecting #10awg conductors) My recommendation would be to install 30amp receptacles, and cord and plug connect the tools.(no one piece of equipment may draw more than 80% of cicuit capacity) The unused conductor should be wirenutted and/or securely taped at both ends.
