bus crashes in u.s. history. clayton: rick: and new challenges for a devastated japan. reports of mass evacuations from the area surrounding a nuclear power plant. as an explosion destroys a building that houses a reactor. and we get reports that some time of emergency at a second reactor in the same complex as japan is rocked moments ago by another aftershock, this one, measuring 6.3, 80 miles from the nuclear plant. greg palkot is streaming live from japan. greg? reporter: we are about 75 miles north of tokyo. and here on this sunday morning, people here are beginning to come to grips with the crisis, with the catastrophe that hit this part of the country. around me we can see cars, boats, trucks, that have been thrown around by the tsunami wave that reached inland from this port city, also, we have