Actually, they used to be on 155.610, as I remember. I've sat there will two radios running in "close call" mode and 460.050 was the only thing police-y that I heard. Heard some construction and a store of some sort, but 460.050 is the only thing that seemed to be near the police station. I was hoping for the 453.675 or 460.150 channel to pop-up, but neither did.
Now, it is possible they are using their MDTs almost exclusively so there just isn't much voice to hear. Also, Ripon is a smaller place so there's that to consider. But, geez... I am almost tempted to call the woman (email, actually) on their license application and ask. :>