When I built my commercial truck shop my insurance company vetoed the idea of a drive over pit, er, foxhole as you are now calling it. (Having been in a few I can tell you it is NOT a foxhole, but I digress.) Point is, check with your insurance carrier before you dig it and buy all the concrete. They didn't think it was safe because of oil and grease entrapment, i.e., a fire hazard. Foolish to me too but there you are.
