Before MAFF or whoever demanded a fortune for thorough testing on anything
it might come in contact with you used to be able to buy a produce mainly
consisting of Caster Oil which, it was said, Moles didn't like the smell of.
Came from the US I believe. You just found a mole hill dug down to the run
and poured some in and the moles moved on.

Jeyes Fluid is good and smelly, that might work.