More drilling, more smog

Regulators aim for industry as levels rise in rural areas

Todd Hartman, Rocky Mountain News

Friday, August 18, 2006

The explosion of oil and gas development on Colorado's Western Slope and in bordering states is driving up smog levels along the Front Range, pushing pollution regulators to consider emissions controls for the industry statewide.

Already, state health officials have proposed ramping up existing pollution limits on oil and gas drillers in Weld and Adams counties to reduce ozone levels that continue to surpass federal health limits in the Denver area.

Now regulators at Colorado's Air Pollution Control Division want to widen their efforts.

They have proposed a reduction in emissions linked to drilling rigs, engines and storage tanks in gas fields across the western half of the state, including hot spots such as the San Juan Basin in southwestern Colorado and the Piceance Basin in Garfield County.

With fossil-fuel extraction quickly accelerating across the West, regulators believe that ozone-forming pollutants are making their way to the Front Range from even farther afield, including drilling-site clusters in northern New Mexico, parts of Utah and the oil and gas basins of southwestern Wyoming.

"It's hard to put a number or a percentage on it, but we know that we get significant ozone concentrations that are transported into the Front Range area," said Mike Silverstein, a top Colorado air-quality regulator.

Not all, or even most, of the blighted air is likely linked to oil and gas development. But regulators say the industry is the one significant source of ozone-forming pollutants that's on the increase, as drillers flock to pump in response to market demand, high fuel prices and a political climate favoring aggressive extraction.

Another significant piece of evidence tying elevated ozone levels to oil and gas exploration: Pollution monitors in rural regions of the West with little industry other than fossil-fuel drilling are showing upward trends.

In perhaps the starkest example of such a pattern, monitors in the lonely landscapes of southwestern Wyoming - save for deer and antelope herds and fast-multiplying oil rigs - showed ozone levels at unhealthy numbers in the winters of 2005 and 2006.

Winter, with its short days and low temperatures, is typically a season for reduced ozone, which thrives on hot weather and long periods of sunlight. The winter ozone spikes were events unusual enough to prompt the Environmental Protection Agency's top air-quality regulator in the Rocky Mountain region to register his concern with state environmental officials in Wyoming last month.

It's ozone from regions such as the Jonah Field in southwestern Wyoming that appear to be, at least in part, pushing up ozone levels in metro Denver. That's because ozone and the pollutants that form it can persist in the atmosphere for days, gathering within air masses that drift around the region and settle over the Front Range, regulators say.

"We have airflow from different regions at different times," Silverstein said. "Predominant airflow is from the southwest, or south, but we get northerly winds, too. We're looking at ozone concentrations at Rocky Mountain National Park that could be influenced by oil and gas emissions in Wyoming."

Colorado regulators say ongoing efforts in other states, including Wyoming, to ramp up emissions controls on oil and gas operations could help reduce ozone levels locally.

Meanwhile, in Colorado, regulators are floating plans to require, among other things, oil and gas storage units that emit more than 20 tons of ozone-forming pollutants per year to add controls. Such a rule would apply statewide and would be in addition to even more stringent emissions controls northeast of Denver, in Weld and Adams counties.

There is a need to move quickly, they say, as Denver is on the cusp of violating the federal government's clean-air standards for ozone.

Statewide emissions curbs could help prevent that, they say, and allow government and industry to avoid an EPA intervention that could make it harder for industry to expand in the region.

"We know we want to get out in front of the curve so we're not looking at (noncompliance)" with EPA standards, Silverstein said.

Ken Wonstolen, senior vice president of the Colorado Oil & Gas Association, said his organization wants to see more evidence that ozone transport from the Western Slope is driving up ozone levels in the Denver region. While not disputing it outright, he said the state needs more data to support requiring more emissions controls.

"I think there's a lot of unknowns" about ozone moving from the Western Slope, Wonstolen said. He argued that the ozone could as easily be linked to heavy population and industry in Las Vegas, Los Angeles and Phoenix, and massive coal-fired power plants in the Four Corners region.

Additionally, he said state regulators are moving too fast. They are trying to push emissions controls statewide at the same time they are calling for toughening smog controls on oil and gas operations northeast of Denver.

Wonstolen believes health officials need to "de-couple" the issues and resolve them one at a time. Such an approach would give the industry more time to grapple with the proposals, he said.

But environmentalists, alarmed by ozone levels that are putting Denver on the edge of public-health standards, say regulators should move ahead.

"It's not going to hurt to reduce ozone-forming compounds from across the state," said Jeremy Nichols of Rocky Mountain Clean Air Action. "Transport (to the metro area) is part of the issue, but (so is) protecting human health in other communities. . . . I don't see why (statewide controls) shouldn't be implemented."

hartmant@RockyMountainNews.com or 303-954-5048