Geoff Liesik, Deseret News
Brock LeBaron, deputy director of the Utah Division of Air Quality, speaks Tuesday, Feb. 7, 2012, at Utah State University Uintah Basin during the public kick-off of the 2011-2012 Uintah Basin Winter Ozone Study. The $5.5-million study involves more than 30 scientists, who are trying to determine what causes high concentrations of ground-level ozone during the winter in the Uintah Basin.

VERNAL — The results of a multipronged, complex study probing what causes the buildup of wintertime ozone in the Uintah Basin were revealed Tuesday, and this much is clear: No one is sure if mandates to reduce emissions will actually solve the problem.

Although oil and gas drilling activity was up in the basin from 2009 to 2012 — during which no significant air pollution reductions were imposed by state or federal regulatory agencies — the winters in Uintah and Duchesne counties were wildly different, as was the ozone problem.

Ozone levels spiked in the winter of 2010-11, reaching levels that were nearly twice the federal threshold.

Flash forward to the next winter, however, there were no days when ozone crept above that same standard.

The study noted it is "unlikely" that overall emissions would have decreased so significantly to account for the lower ozone levels recorded between the two seasons.

Scientists with the National Oceanic and Atmospheric Administration and others heavily involved in the study noted at least one primary difference — lack of snow cover on the ground.

Uintah and Duchesne counties host 5,000 natural gas wells and 3,300 oil wells — supporting Utah's 11th ranking in the country for crude oil production and its No. 9 slot in gross natural gas production. The basin is also home to the 500-megawatt Bonanza power plant southeast of Vernal, which can be blamed for pollutants that contribute to the overall problem.

Scientists know that energy development plays into the problem, but the theme that emerged from this latest look at the cause is that weather is a driving factor behind ozone formation in the basin.

Brock LeBaron, deputy directory of the state Division of Air Quality, said the challenge of understanding the Uintah Basin's winter ozone problems is that science hasn't caught up.

Most research on the subject looks at summertime ozone formation because the phenomena of such a problem playing out in a rural area in the cold of winter is novel.

The study tapped multiple partners and research institutions as air quality regulators try to get ahead of the problem being possibly regulated by the federal government.

Western Energy Alliance, which represents oil and gas producers, funneled nearly $2.2 million into multiple years of the effort to attempt to understand the problem.

"These two studies will significantly advance the scientific understanding of winter ozone formation, and will inform regulators and the industry on how to effectively reduce emissions," said Kathleen Sgamma, governmental affairs director for the organization.

Scientists who spoke Tuesday at a Vernal conference to reveal study details said the lack of information on the complex atmospheric play at hand leaves them reluctant to recommend mandatory pollution control strategies.

LeBaron said the state and others involved in the study want to work with the industry to come with up with possible voluntary ideas for reducing emissions.

"We will work with producers to come up with a list of things they may be able to do to respond to episodic condition," LeBaron said. "That's in process — things like only drill during certain times of the year. We can describe the parameters, present that this is what you are up against and ask what they are going to do to respond to that."

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