Reducing nitrogen oxides from oil and gas exploration and production


On this page: Nitrogen oxides emissions and upstream oil and gas operations | Timeline of state actions | NOx Reduction Steering Committee | Technical meetings for the NOx Reduction Steering Committee members | Public information meetings on the NOx Reduction Steering Committee’s progress


Please note: If you would like to request a Spanish interpretation, please email cdphe_apcd_outreach@state.co.us.
Tenga en cuenta: Si desea solicitar interpretación al español, envíe un mensaje por correo electrónico a cdphe_apcd_outreach@state.co.us.

Nitrogen oxides emissions and upstream oil and gas operations


Oil and gas exploration and production processes are collectively known as the “upstream” operations. Upstream oil and gas operations include:

  • Drilling new oil and gas wells.
  • Hydraulic fracturing, or “fracking.” This involves injecting water, sand, or other materials into a well to help with extracting oil and gas.
  • Completing oil and gas wells. This can involve encasing a well in concrete, or other steps to prepare them for production.
  • Producing or extracting oil or gas from wells.

Upstream oil and gas operations are a significant source of nitrogen oxides, or “NOx,” emissions. NOx emissions, along with volatile organic compound emissions, are what’s known as “ozone precursors.” That means when NOx emissions react with volatile organic compound emissions in heat and sunlight, they form harmful ground-level ozone pollution.

Timeline of state actions


In March 2023, Governor Polis directed the Air Pollution Control Division to develop rules that will apply to upstream oil and gas operators in areas of Colorado that do not meet federal ozone pollution standards. According to Governor Polis’s direction, these operations need to achieve:

  • A 30% reduction in NOx by 2025.
  • At least a 50% reduction in NOx by 2030.

In December 2023, Colorado took action designed to meet the 2025 NOx reduction target. The Colorado Air Quality Control Commission achieved this by implementing regulations to reduce emissions from stationary engines and drilling and fracking  operations.

Also in December 2023, the commission established the planning process for actions to meet the 2030 NOx reduction target. To help explore options, the commission directed the division and the Colorado Energy and Carbon Management Commission to establish a new NOx Reduction Steering Committee.

In March 2024, the CDPHE Air Pollution Control Division established the new NOx Reduction Steering Committee and began the planning process to meet the 2030 reduction target.

NOx Reduction Steering Committee


The NOx Reduction Steering Committee is a technical working group. The committee  will develop recommendations for NOx pollution reductions from the upstream oil and gas operations. The committee will complete its recommendations by the end of 2024. Committee members include:

  • Hunter Dorn, Xcel Energy.
  • Derek Eggert, Chevron.
  • Nini Gu, Environmental Defense Fund.
  • Keith Hay, Colorado Energy Office.
  • Greg Howes, United Power.
  • Katie Keefe, Adams County.
  • Meredith Knauf, Prairie Operating Co.
  • Neil Kolwey, Southwest Energy Efficiency Project.
  • Jason Maxey, Weld County.
  • Bill Oberman, City and County of Denver.
  • Dida Osbourne, Energy and Carbon Management Commission.
  • Kate Percival, Civitas.
  • Janessa Salgado, Oxy. 

Public participation opportunities


Technical meetings

 The NOx Reduction Steering Committee began meeting in March 2024. The members committed to holding meetings once a month for at least six months. During these meetings, members engage in technical discussions on potential strategies to reduce NOx pollution. Meetings are held virtually. Members of the public are welcome to observe. Register to attend a meeting:

Past meetings

Written public comments

You can send written comments or questions on NOx reduction planning to cdphe.commentsapcd@state.co.us. Please include “NOx Reduction Planning” in the subject line. 

Explore tips for making effective public comments.

Public information meetings


The CDPHE Air Pollution Control Division will also host public information meetings on the NOx Reduction Steering Committee’s progress and recommendations. These meetings will be separate from the committee’s regular technical discussions. Public information meetings will provide:

  • An overview of the committee’s work.
  • Opportunities for the public to comment and ask questions.

As of March 2024, the public information meetings have not been scheduled. This webpage will be updated once public meeting dates and registration is available.

Visit the division’s public participation web page to learn about upcoming opportunities to get involved.