Colorado Air Pollution from Oil and Gas
Oil and gas development is contributing to a decline in Colorado air quality
The Colorado Air Pollution Control Division has observed that ozone levels in rural areas are gradually increasing along with increasing oil and gas exploration and development. In some areas, ozone levels are approaching (and occasionally exceeding) the federal standard of 0.08 parts per million (ppm) or 80 parts per billion. In southwestern Colorado, air monitors in Mesa Verde National Park show that smog levels have steadily risen in the last decade, with some of the highest readings being recorded in the last two years.
The Colorado Air Pollution Control Division reports that during the period 2000-2005, the following maximum ozone levels were measured:
- Mesa Verde (southwest Colorado): 0.082 parts per million (ppm).
- Ignacio, Colorado (southwest, near the NM border): 0.072 ppm.
- Shiprock, New Mexico (near Colorados Four-Corners area): 0.81 ppm
- Utah Canyonlands (southeast Utah): 0.079 ppm
Air pollution from oil and gas development is significant - and it's on the rise
Smog forming compounds and other air toxics are released at every stage of oil and gas development. Drilling rigs emit a variety of air pollutants including NOx, carbon monoxide and carbon dioxide. During well completion, tons of VOCs may be vented or flared. Oil and natural gas condensate tanks and glycol dehydrators release VOCs. Compressor stations emit a variety of ozone-forming compounds, as well as other air pollutants. And according to data compiled by Rocky Mountain Clean Air Action, a single EnCana natural gas processing plant in Rio Blanco County has the potential to release nitrogen oxides, carbon monoxide and volatile organic compounds equal to the emissions from 43,000 cars!
Below are three examples of significant sources of air pollution from oil and gas operations in Colorado:
- Condensate tanks collect liquid hydrocarbons during oil and gas production. The State estimates that there are 152 large condensate tanks in the Denver metro area that annually release 11,868,000 pounds (5,900 tons) of volatile organic compounds (VOCs). In Garfield County, VOC emissions from condensate tanks exceed 4,700 tpy.
- Glycol dehydrators are used to separate water from gas. The State estimates that there are 38 glycol dehydrators outside the Denver metro area that annually release 2,318,600 pounds (1,160 tons) of VOCs.
- Engines, such as those used to compress natural gas, currently have no pollution controls, despite the fact that they emit large volumes of air pollutants. For example, on a yearly basis, a single 1200 horsepower reciprocating internal combustion engine at a compressor station can release VOCs, NOx and carbon monoxide equivalent to the emissions from 8,000 cars.
Data from the Colorado Department of Public Health and Environment's oil and gas emissions inventory show that VOC emissions from existing oil and gas facilities are increasing statewide. Based upon the inventory data for 2004 and 2005, oil and gas production facilities are responsible for more than 50% of all VOCs released from stationary sources in the state of Colorado.
According to Rocky Mountain Clean Air Action, in some counties, such as Garfield, Las Animas, Rio Blanco, and San Miguel, oil and gas production facilities are responsible for more than 90% of all smog-forming compounds released by stationary sources.
|
County |
Total smog forming compounds from stationary sources (tons/year) |
Total smog forming compounds from oil and gas |
Contribution of oil and gas to pollution |
|
Delta |
139 |
46 |
33% |
|
Dolores |
143 |
112 |
78% |
|
Garfield |
7522 |
7174 |
95% |
|
La Plata |
718 |
485 |
68% |
|
Las Animas |
453 |
419 |
92% |
|
Mesa |
1340 |
506 |
38% |
|
Rio Blanco |
2778 |
2696 |
97% |
|
San Miguel |
542 |
501 |
93% |
|
Weld |
53372 |
50731 |
95% |
Oil and gas development continues to expand throughout Colorado. As of early September, 2006, the COGCC was receiving, on average, more than 100 additional well permit applications per month, statewide, as compared to its monthly average during 2005. Of the 2006 permit applications received, more than 54% are in counties where, up until December, 2006, there were no restrictions on VOC emissions.
In December, 2006, the Colorado Air Quality Control Commission approved several
new restrictions on the oil and gas industry in an effort to curb emissions of ozone-forming compounds affecting air quality across the state and in the Denver region. Read more about the 2006 Air Quality Rule Changes.
According to an article in the Rocky Mountain News, the new rule includes:
- Cutting emissions: Oil and gas operators in a drilling region northeast of Denver must cut overall emissions of volatile organic compounds (VOCs) from condensate storage tanks by 75 percent before May 1, 2007. That's an increase from current rules requiring cuts of 47.5 percent.
- New emission controls: Statewide, oil and gas operators must, for the first time, install emission controls on condensate storage tanks that emit more than 20 tons per year of VOCs. New emission controls on natural gas engines and dehydrating equipment also were approved. The new rules will be phased in over the next two years.
- Air quality reporting : The state's Air Pollution Control Division must provide an annual report on how the oil and gas industry is affecting air quality across the state.
Source: Todd Hartman. Dec. 418, 2006. "Air Panel OKs New Controls on Oil, Gas Industry Pollution." Rocky Mountain News.
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