10 miles? Are they suspecting a large nuclear weapon? In the absence of finding an actual bomb, I think an evacuation of any sort would be an overreaction. But I don't think that a terminal dump is. As was said upthread, here is a real risk of having explosive components brought in by different people and later assembled. Rescreening everybody to doublecheck that this isn't the case doesn't seem that much of an overreaction to me. Many here are in favor of a "risk-based" approach. It seems reasonable that once you've found one passenger with a bomb component that the risk is now higher than others may have one as well.