They should be able to test that underground wire to see if one of the wires has a break in it (also neutral wire) with a continuity test of each leg (it has 2 wires and the neutral) each leg is carrying 120volts together they amount to 240V , The neutral is the third wire and is needed to complete the circuit. (but Im sure ya hubby knows all this.) If the "break" is able to be located yes it can be spliced right in place after digging that section up and reconnecting it with a new section of wire . And using water proof splice connectors .Under the drive they may need to shoot a new wire and may as well replace the whole run to make sure it does not happen again.
Good Luck