like it all shook. >> reporter: daylight reveal what had looks like a war zone. the house where the natural gas exploded, nothing more than a crater. it was the home of william and beatrice hall, a couple in their 70s. they were killed. next door a 4-month-old boy, a 16-year-old and one of their parents also killed. ed pawlowski took us to the scene. this is the house that started it. it's gone. >> yes, it's gone. >> reporter: this is just the latest explosion. three weeks ago, in philadelphia, this blast killed one. and last year in california, eight were killed in san bruno. last year there was a spike in the number of deaths involving pipeline explosions. watch dog groups don't believe the federal government is doing enough to safeguard us from these aging pipelines. there are nearly 2 1/2 million miles of pipes delivering natural gas to our homes. >> are we inspecting enough? no. are we putting money into this, giving the attention? no. >> reporter: in that california explosion, it turns out there were problems with the pipe.