NPR: Air Quality Concerns Threaten Natural Gas's Image

From NPR:

Massive stores of natural gas that lie underneath big portions of the United States offer a cleaner source of electricity to a country that relies heavily on coal, but producing all that gas also can pump lots of pollution into the air.

Gas production already has caused unhealthy air in Wyoming's Sublette County and Utah's Uintah Basin. And experts project that booming shale gas developments like Haynesville, stretching through Texas and Louisiana, and Marcellus, which lies beneath several Mid-Atlantic states, will start contributing to unhealthy levels of ozone or smog in coming years.