those containers. we ll keep you updated on that as well. jon: residents of san bruno, california are now reliving a nightmare in the northern part of that state, returning to the ashes that used to be their homes. this after that deadly gas explosion tore through the community last week. the huge fire ball consumed nearly 50 homes, killing at least four people in that small town near san francisco s airport. now, pacific gas and electric is going around checking all of its gas lines after the intense explosion and fire. could something like this happen in your town? how common are these gas lines? where are they? the executive director for pipeline safety trust karl wao eupler joins us on the phone. first of all, we don t tperblly know of the cause of that accident, that pipeline explosion last week, do we? that s correct. i don t think the cause has been released yet and i m not even sure they know how many are dead yet. jon: there are all kinds of mysteries around this one. how bi