They most likely won't even see it, as you will be spending the majority of your time talking face to face with an active member. The chances of them seeing a small tattoo on your back are slim to none. That being said I don't think a small tattoo would be an issue anyways. Lots of girls have small tattoos on their wrists, ankles, feet, etc coming in to college, as long as it's tasteful they'll probably think nothing of it.