Uinta Basin
2018 State of the Environment Report (AQ)

Uinta Basin Oil Well

On August 3, 2018, EPA designated parts of the Uinta Basin as a Marginal nonattainment area for the 2015 ozone standard (479.91 KB).  The nonattainment boundary was defined as all land in Uinta and Duchesne Counties below a contiguous, external perimeter of 6,250-feet elevation.

A Marginal designation is the least stringent classification for a nonattainment area and doesn’t require the state to submit a formal State Implementation Plan (SIP).  However, the area will be required to attain the 70 part-per-billion (ppb) ozone standard by August 3, 2021. Several new requirements will be implemented in the area:

  • New major sources must include emission offsets in their permits.
  • Federal projects must undergo general conformity assessments prior to approval of the projects to demonstrate no further decline of air quality.

While DAQ won’t require new control technologies at this time, the division will work to ensure compliance with current rules and prepare for the possibility of nonattainment. If the area fails to meet the standard in 2021, it would be classified as Moderate and subject to more stringent requirements.

Multi-jurisdictional Air-Quality Issues

Approximately two-thirds of currently producing oil and gas wells — ninety percent of the gas production and half of the oil production in the Uinta Basin — are located in Indian Country (2.39 MB) where the tribe and EPA have regulatory authority. Because EPA views the Uinta Basin as a single airshed and ozone nonattainment area, the design value for determining nonattainment-area classification is triggered by air-quality data from the monitor with the highest ozone values — in this case, the Ouray monitor in Indian Country. The state’s monitors in Roosevelt and Vernal also see exceedances of the standard during the wintertime ozone events, although not at levels as high as those found at the tribal monitors.

A good working relationship between DAQ and the Ute Tribe is critical for addressing air-quality challenges, arriving at effective control strategies, and minimizing emissions in the ozone nonattainment area. To that end, DAQ has been working collaboratively with the tribe to tackle cross-jurisdictional air-quality issues that impact both entities.

The Tribe is overseeing air-quality monitoring on tribal lands and contributing data for the area’s emission inventory. DAQ and the Tribe, along with the Bureau of Land Management (BLM) and EPA, collaborated on an aerial helicopter infrared (IR) camera study over state and Indian lands in the winter of 2018. The aerial study was combined with a ground-based IR camera study of the same sites. While the final report hasn’t been published yet, the study reached several important conclusions:

  • Cold temperatures reduce the ability of IR cameras, especially in aerial applications, to detect emissions.
  • Newer sites (with more tanks) have the most detectable tank emissions.

In another collaborative study on state and Indian lands, oil and gas companies agreed to allow the collection of liquid and gas samples at their well sites. These samples will provide data on the composition of these products, leading to better emission inventories and modeling.

The EPA has proposed amendments to the Federal Implementation Plan (FIP) for Oil and Gas on Indian lands that would include the Uintah and Ouray Reservation in the FIP. These amendments would allow oil and gas development to continue in areas designated as nonattainment for the 2015 ozone standard. (The current FIP applies only to areas designated as attainment, attainment/unclassifiable, or unclassifiable).The EPA is also working on a reservation-specific FIP that would reflect current BACT requirements by the state for oil and gas operations on state lands. This reservation-specific FIP is still under evaluation.

Air Quality Rules

Well Head

The Air Quality Board approved new rules for oil and gas sources in January 2018 to replace source-by-source permitting with a streamlined permit-by-rule approach. These rules also establish a registration process for all oil and gas sources in the state and their inclusion in the triennial emissions inventory.

The registration rule applies statewide and ensures DAQ has essential information on oil and gas sources, their emissions, and the equipment and controls they have. This registration process has addressed concerns regarding the existence of de minimis sources and the appropriate application of the small-source exemption. The rules have been positively received by both industry and environmental advocacy groups. An additional rule currently proposed by the Air Quality Board would control associated produced-gas from oil and gas wells so these facilities can continue to be be regulated under the permit-by-rule approach.

This emission inventory for oil and gas sources will provide DAQ with important information to help it model air-quality impacts and potential exceedances of the National Ambient Air Quality Standards (NAAQS) from oil and gas operations. Data collected for the 2017 emission inventory are currently undergoing quality-control review and should be available soon.

Uinta Basin-based Compliance Inspector

The Uinta Basin contains the largest concentration of oil and gas production facilities in the state. Due to the long distance between Salt Lake County and the Basin, DAQ inspectors were spending more time traveling to and from the Basin than inspecting the oil and gas sources there. To address this issue, DAQ hired a full-time compliance inspector who lives in the Basin. The inspector works with the producers in the area to facilitate use of the ULend IR camera and conducts inspections. When the IR camera is not in use, the inspector uses it to detect leaks at oil and gas sources. The reduced travel time and permanent presence in the Basin has greatly improved the efficiency of DAQ’s compliance efforts in the area.