What kind of bee/wasp/hornet thing is this?

Question:out by my garage, theres kind of a dirt wall and recently i've seen these wasp/hornet looking things burrowing in it. Their bodies kind of look like a hornet or yellow jacket, only they're black with white stripes, not yellow. They also fly a whole lot faster than a typical bee or wasp. they range in size from a half inch or so up to over an inch. Anyone have any ideas what they are?

Answers:
We see these occasionally~they are called a bald faced hornet