It is becoming a tradition in Wyoming: the annual ozone warnings for rural Sublette County.

2011 is no different that the last few years, as once again the Wyoming Department of Environmental Quality will be issuing elevated ozone warnings for the town of Pinedale and the surrounding areas.

The situation in Pinedale, which is the county seat for Sublette County, is quite interesting because ozone warnings are generally rare in the United States. More interesting is Pinedale’s population. The 2010 census has Pinedale’s population at just over 1,500, which even for Wyoming standards is pretty darn small.

So what’s causing all of this? Well a few factors are at play. The first is geography. Pinedale sits in a valley, so often there is an inversion making it hard for air pollution to escape. Then there is weather. When sun does get through, it hits the snow-covered town in the winter and bakes any pollutants. The baking causes ground level ozone, a key component of smog. The smog can’t escape because of the inversion caused by the valley.

But let’s back up to that population figure of 1,500. Smog is generally a part of big cities like Denver or Los Angeles, not Pinedale. But Pinedale has something else: thousands of oil and natural gas wells. The Casper Star Tribune reports, “Thousands of oil and gas wells have been drilled in Sublette County in recent years. Some area residents have long contended the lucrative Pinedale Anticline and Jonah gas fields are contributing to the region's elevated levels of ozone.”

Pinedale is a unique situation because of the mountains, weather and the energy production in the region. The state of Wyoming has been monitoring the Pinedale situation since 2005, and since 2009 energy companies are said to have been “volunteering” to take long-term actions to reduce the ozone-forming emissions in the area. But still, warnings remain as another calendar is hung on the wall.

So next time you see a smoggy picture of Los Angeles or Denver perhaps you can think to yourself, “Man, it looks like Wyoming out there.” Alright maybe that won’t happen. But if it does, you wouldn’t be totally off base.

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