Smog along Colorado’s Front Range is thickening again, exceeding federal standards, and government-backed scientists say the oil and gas boom is partly to blame.
If the industry expands, scientists at a conference this week said, air quality probably will deteriorate.
“It’s going to be harder to meet our clean-air requirements,” said Gabrielle Pétron, a researcher in the National Oceanic and Atmospheric Administration’s global monitoring division.