Is there an easier way to check to check , other that digging up the
yard?

Disconnect hot, ground and neutral wires at service panel. Unscrew lamp at
fixture. Check resistance between ground, neutral and hot. All should read
infinity. If there is a short between the hot and neutral it will be close to
zero ohms, same with ground. If that is the case get out the shovel and
consider using plastic conduit. HTH

Joe