How to Get Bots to Only Mine
A miner should NEVER be connected to the logistic network (wifi-icon next to the powerbuttom).
Lock ALL slots of a miner to the stuff they actually need to mine.
Set them to a program/behaviour which allows them to ONLY mine the stuff they need to mine.
Lock your miner to a node and let another bot do the ore transports via the “transport route” logistics option (right click the wifi-signal and check the box at the very bottom; then assign it a linked storage depot and set the miner as a target),
You don’t explicitly need behavior controllers on the miners themselves. A basic signal reader that you assign from the [STORE] register will take care of that, and the output from the [SIGNAL] will control what they mine. The dedicated hauler is essential once your base is bigger than about 40 tiles.