Colorado's Ozone Challenge
Colorado's Ozone Nonattainment Area Planning
While air quality has improved greatly over the past several decades and ozone concentrations generally trend downward in the Denver Metro/North Front Range area, the area has failed to comply with increasingly stringent federal standards. In June 2018, EPA classified the Denver Metro/North Front Range (DM/NFR) as a “marginal” nonattainment area for the 2015 8-hour ozone standard, effective August 3, 2018. The attainment deadline for the 2015 standard is August 3, 2021, based on 2018-2020 ozone season data. In January 2020, EPA classified the DM/NFR as a “serious” nonattainment area under the 2008 ozone standard. The attainment deadline for the 2008 standard was July 20, 2021, based on 2018-2020 ozone season data. The area did not attain the standard and will be downgraded again to “Severe” non-attainment for the 2008 8-hour ozone standard.
The Air Pollution Control Division (Division), the Air Quality Control Commission (Commission), and the Regional Air Quality Council, along with other local partners, continue to evaluate and implement control strategies aimed at reducing emissions, particularly precursors to the formation of ozone - nitrogen oxides (NOx) and volatile organic compounds (VOCs). We also will continue to seek ozone precursor pollutant reductions with other on-going reduction strategy directives as well, including those seeking GHG and visibility impairing pollutant reductions.
Ozone and Air Quality Fact Sheet / Hoja informativa sobre el ozono y la calidad del aire
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Colorado is actively planning next steps in addressing ozone in the North Front Range. Please join us for an upcoming public listening session. APCD is hosting listening sessions that will share basic ozone information, identify planning processes and potential reduction strategies, and provide opportunities to share concerns and suggestions.
- May 31st, 2023 - 5:30-7:00 pm, register to attend over zoom
- August 19th, 2023 - 10-12 pm, register to attend over zoom
Past Public Listening Sessions
- February 21st, 2023 - 6:00-8:00 pm, virtual.
- Public listening session video recording: in English/en español
- Presentation slides: in English/en español
- January 26, 2023 - 12:30-2:00 pm
- Public listening session video recording: in English
- Presentation slides: in English/en español
- May 14, 2022 - 10:00 am - 12:00 pm
- Public listening session audio recording
- Public listening session video: in English/en español
- Presentation slides
- April 26, 2022 - 6:00 am - 8:00 pm
- Public listening session recording: in English/en español
- Agenda (in English/en español)
- Presentation slides
- Jan 22, 2022, 10am - 12:30 pm - public listening session recording
- Agenda (in English/en español)
- Presentation slides
- Jan 20, 2022, 6pm - 8:30pm - public listening session recording
Contact us with any questions at cdphe.commentsapcd@state.co.us with "Severe Ozone Planning" in the subject line
Work Group Meetings
Past meeting:
- #1 -February 27, 2023 - 10:00 - 11:00 am
- #2 - March 27, 2023 - 10:00 - 11:00 am
- #3 - April 24, 2023 - 10:00 - 11:00 am
- #4 - May 22, 2023 - 10:00 - 11:00 am
Next meeting:
- #5 - June 26, 2023 - 10:00 - 11:00 am
The Division plans to host a number of industry meetings in 2022 for sources of NOx or VOC over 25 tons per year in the Non-attainment area. If you are interested in attending these meetings, please contact Jeramy Murray.
Scheduled stakeholder meetings
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Upcoming - February 16, 2022
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Past Stakeholder Meeting
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February 8, 2022
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Additional information:
- In 2017 the Division launched a voluntary emission reduction program with industry in the DM/NFR area. Program participants receive emails two to three days before a forecasted high ozone day. Participants are encouraged to implement voluntary emissions reduction actions on the forecasted high ozone days.
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In July 2018, the Commission adopted Reasonably Available Control Technology (RACT) requirements for major sources of NOx in the DM/NFR
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In November 2018, the Commission adopted categorical RACT requirements for breweries and wood furniture coating operations that are a major source of VOCs in the DM/NFR.
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In July 2019, the Commission adopted VOC content limits to reduce emissions from consumer products and architectural, industrial and maintenance coatings.
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At the Commission's directive, the Division initiated and led the Statewide Hydrocarbon Emissions Reduction (SHER) stakeholder process and the Pneumatic Controller Task Force (PCTF) over the 2018-2019 timeframe. The SHER Team evaluated topics including the frequency of leak detection and repair inspections, transmission segment compressor emissions, and natural gas-driven and zero emission pneumatic controllers state-wide. The SHER Team’s efforts informed a 2019 rulemaking proposal. The PCTF completed a study of rates of improper operation for pneumatic controllers in the DM/NFR nonattainment area in June 2020. The PCTF used the results of this study to understand the costs and effectiveness of the current pneumatic controller inspection program. PCTF findings and recommendations were presented to the Commission in August 2020.
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In September 2020, the Commission approved new rules that require emissions monitoring at oil and gas sites during the early stages of operations at new oil and gas wells. The rules require operators to report carbon dioxide and N2O emissions. The rules also set emission standards for natural gas-fired reciprocating internal combustion engines equal or greater to 1,000 horsepower.
For additional information, see the Regional Air Quality Council air quality planning.