It was a chilly morning. The sun crested the Wind River Mountains to reveal the delicate wisps of stray cirrus clouds far above the Upper Green River Valley (UGRV).

The high-level clouds shined orange in the early morning light. They contrasted against a deep-blue sky.

Just above the horizon, a thin layer of brown haze hung over the New Fork and Green River valleys. Below the haze, a large stand of gas rigs bustled with activity.

Ted Porwoll, Forest Service air quality technician, was hard at work. On a bluff above the New Fork Valley, Porwoll was calibrating equipment at the Boulder monitoring station near Paradise Road.

The $250,000 site is notorious. Last winter the site recorded ozone levels of 122 parts per billion (ppb) in an eight-hour average, well in excess of government standards.

Surrounded by sophisticated monitoring equipment, Porwoll sipped on a mug of coffee in the site’s climate-controlled shed.

“The information we’re collecting here can be used (for government regulations),” he said. “There’s a lot of stuff going on here that’s precedent-setting.”

Of all the instruments that adorn the small shed, nothing garners Sublette County residents’ attention more than the ozone monitor.

Aesthetically, the machine is nothing special. It looks like an over-sized VCR with clear tubes protruding from it, but inside it is sensitive enough to measure ozone down to the billionth.

The ozone monitor is paired with another machine that produces ozone in exact quantities. The second machine is used to test the monitor. In prearranged sequences, the ozone-producing machine extracts an exact amount of the gas and feeds it to the monitor. Site operators compare the monitor’s reading against the amount of ozone produced to test its accuracy.

The entire site uses redundancy to ensure accurate measurements. Any data that deviates from precision is excluded.

But it doesn’t require a precision device to notice the thin brown cloud that hangs over the valley below.

“If it’s black, it tends to be particulate matter.” Department of Environmental Quality (DEQ) staff engineer Jennifer Frazier said. “The brown is generally NOx.”

Full Story: http://www.subletteexaminer.com/V2_news_articles.php?heading=0&page=72&story_id=925