According to the Associated Press, last year in western Wyoming fracking resulted in ground-level ozone, the main constituent in smog, at levels that were worse than that seen in smog-ridden Los Angeles.
Benzene levels considered dangerous to human health have been detected in Dish, Texas, which is near numerous fracking sites, the AP also reported.
On the other hand, drilling sites in four counties in Pennsylvania have not been associated with air emissions problems, the AP said.
Operators of new "fracked" natural gas wells will have to capture any additional natural gas using technologies that are already available, according to the EPA rules.
They then will be able to sell that extra gas, making the new regulations ultimately cost-effective and even cost-saving, McCarthy said.
Between now and Jan. 1, 2015, natural gas operators must either "flare" (burn) gas emissions or use "green completions" technologies to prevent gas from escaping. Starting in 2015, however, companies will have to use green completions.
"Completion" refers to a process taking place over three to 10 days, as a well transitions from being drilled to actually producing natural gas. Much of the pollution from fracking is thought to be emitted during this period.
The EPA estimates that about 13,000 wells are fractured or re-fractured each year in the United States. Some states, such as Colorado and Wyoming, already regulate the fracking industry, the AP noted.
"This is the first national standard to reduce air pollution from hydraulically fractured wells," McCarthy said. "When implemented, it will require operators to capture gas that would otherwise escape into the air, keeping harmful pollution out of the air."
But the NRDC believes more must be done. In their statement, the group said it is "disappointed that EPA
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