"Living in the middle of a natural gas boom can be pretty unsettling. The area around the town of Silt, Colo., used to be the kind of sleepy rural place where the tweet of birds was the most you would hear. Now it's hard to make out the birds because of the rumbling of natural gas drilling rigs." ...

"Companies can drill 20 wells or more at a single site. They come back again and again over the course of years. Each time, there's an onslaught of strange smells. People living near the wells complain about itchy eyes, scratchy throats and getting sick to their stomachs. 'I worry about my health. I worry about my kids' health,' Ray says.

But the truth is, Ray and his other neighbors are guessing. They know almost nothing about what's happening on the well pads around them. They just wonder: What's in those fumes that blow into their yard? What's in that smell?"

Elizabeth Shogren reports for NPR's All Things Considered May 15, 2012. [2]