Level up enough to get the "Animal friend" perk, then get to the quest where you test out the Repellent Stick on the Mole Rats. Normally the Mole Rats will attack on first sight, but because you have got the perk, they won't. You can hit the Mole Rats with the Repellent Stick once without them attacking, even if there are others nearby. Note: This will not affect the completion of the quest.
