Why get rid of her?
So she's not girlfriend material.
Big deal.
You can keep fvcking her and look for a better prospect on the side and ditch her when you secure the new branch.
As for getting rid of her now if you really must and avoiding any negative pitfalls should she choose to go psycho on you?
Well just make sure you don't give her any goodbye sex as if she's fvcked in the head enough she might go to the cops, lie and say you raped her and provide them with some residual DNA evidence to prove it.
Also before you breakup with her make sure to get all of your stuff out of her place if any of it is there and save any voice messages, emails, letters, pictures of you two happy together and indicating you were in a seemingly happy relationship together if she tries to go to the cops using the "you're a random creepy stalker" card.
Also if you have any humiliating videos lying around of you nutting on her face or anything else embarassing she might not want to get out to the public this may also serve as a deterrent to her going psycho on you.
Unless you got with a borderline or bipolar or a schizo I think you really have nothing to worry about if you just pull the cowardly chick breakup tactic and just stop contacting her.
If you don't want it to be that cold and simple though just leave a little note that indicates you know about her lies and cheating and that you two are through.
Straight and to the point.
No scolding her or trying to make her feel sorry or bad about what she did.
Thats what a chump would do or a morality crew AFC and it will not have the desired effect anyway since the chick will never be sorry but rather get off on having effected you so deeply.