A ground water heat sink should work too, it works for heat pumps. A
small well drilled about 50 or so feet down or even a slightly bigger
diameter one not as deep should keep the water fairly cool, just dip a
set of coils into it to let the heat disapate and off you go. You
could even use a straight pipe down and then back up if the hole were
deep enough, the 50 foot one should work for this. Of course the water
would need to cover alot of the pipe.