One of the borate dispensing contractors has a terminal/loading station here at the airport. DC-10 being one of their bombers, about 3 weeks ago it flew off to the north and didn't return until yesterday. It was no doubt in use somewhere to the north. It's back today and it brought one of it's little Chinook buddies. They haul that borate like they do cement powder, in pneumatic trailers. Quite a process to watch when they get busy.