"You could have a flare literally right outside somebody's bedroom window under the setback," McCawley said. "I don't know that any company would do that on purpose. But it would be legal."
Also, McCawley noted that the setback provision treats all locations equally, not taking into account the potential for some gas drilling sites in narrow hollows to be subject to weather inversions that trap pollutants near the ground.
McCawley said DEP officials were correct when they told lawmakers his data showed no public health emergencies. He said he found no violations of national air quality standards.
"I want to make sure that nobody takes away the wrong message, that there are things out there that are an imminent danger," he said.
But McCawley said he did find locations where pollutant levels, especially for toxic benzene, violated public health guidelines published by the U.S. Centers for Disease Control and Prevention.
"It is in the report," McCawley said. "DEP has not tried to cover this up or hide it from anybody. It is kind of hard to find. It's in the back of the report."
The DEP has suggested lawmakers could consider changing the setback provision so that the 625-foot distance was measured from what they called the "limit of disturbance," or the outmost sediment control barrier at each well pad.
But McCawley recommended instead that more air-quality monitoring be done at drilling sites, and that the data be used, along with public health guidelines, to require the best pollution control systems be used by industry.
"This would be a more practical approach," McCawley said.
Reach Ken Ward Jr. at kw...@wvgazette.com or 304-348-1702.