Honestly, 30 lbs in 8 weeks is 3.75 lbs per week. If you lose 10 in the first week (it can happen when doing strict Atkins, by the book), that leaves 20 lbs in 7 weeks, which is still 2.75 lbs per week...
I'm not saying it is not "doable" but only if you are strict and do follow the rules. Read the Atkins book. Only eat foods off the induction food list (not low-carb pasta), exercise moderately and you may make your goal.
That being said, it is not recommended to try losing more than 2 lbs per week (after the first week or two of a low-carb diet because you lose some water weight during that time) or you are less likely to keep it off.