There are a range of different traps and deterrents on the market
specifically targetted at controlling moles. We have two different
humane solutions available, the first being a sonic device that you
'plant' in the ground. The Molechaser as it is called, produces a high
frequency sonic sound that the moles are supposed to find irritating
and encourages them to move elsewhere.

The second option is a Swedish import called Sork Anti-Mole Bulbs. I
have no idea what is in the bulbs but again, you 'plant' these around
the garden and the smell encourages the moles to move on. They have
been available in Sweden for over 9 years and claims to be the only
natural product that makes moles move on without the use of poisons.

http://www.gardenoasis.co.uk/wildlife-c-68.html

Good luck!

Garden Oasis