http://www.upi.com/Science_News/Technology/2012/11/20/Boston-said-riddled-with-natural-gas-leaks/UPI-35811353446579/#axzz2CrOGXpGa
One has to wonder if this is typical of all major cities in the US? Lately I have seen a lot of articles popping up on the net about natural gas explosions and the frequency seems to be increasing. Here's the latest one:
http://news.yahoo.com/2-workers-hurt-natural-gas-explosion-near-price-042047536--finance.html;_ylt=A2KJ3Cc0zKxQJVsADzbQtDMD