2008 8-Hour Ozone Standard State Implementation Plan (SIP) Control Strategy Evaluation Effort


In 2012, the Denver Metro/North Front Range Area was initially designated as Marginal nonattainment for the 2008 National Ambient Air Quality Standard (NAAQS) for ozone July 20, 2015. Because the region did not demonstrate attainment by the end of the 2014 ozone season, the region was reclassified by the U.S. Environmental Protection Agency (EPA) to a Moderate nonattainment area, which modified the attainment deadline to July 20, 2018.  This required the development and submittal of an State Implementation Plan (SIP) which was approved by the Air Quality Control Commission (AQCC) November 2016 and submitted to EPA May 2017.

As part of the SIP development process, a Reasonably Available Control Measures (RACM) analysis was conducted, which demonstrated that the state has adopted all reasonably available control measures needed to meet the Reasonable Further Progress (RFP) requirements and demonstrate attainment as expeditiously as practicable. As part of this effort, the Regional Air Quality Council (RAQC) Board formed three subcommittees to evaluate potential strategies for incorporation into the upcoming and/or future SIPs.

Although the Moderate Area SIP has been submitted to EPA and there is not currently a subsequent SIP requirement for either the 2008 standard or the 2015 standard, these subcommittees continue to meet on an as-needed basis to evaluate various feasible control strategies aimed at reduce emissions and improve air quality.

All subcommittee meetings are open to the public and interested stakeholders.

Click here for a list of members by committee.

**Upcoming meetings are posted on the RAQC calendar page, which can be accessed here.**

Email Sign-up:  click here to be added to any of the subcommittees’ interested parties email list to receive notifications about future meetings.

Ozone Modeling Efforts
To aid in the planning process, modeling efforts are continually being conducted to better understand the effectiveness of various control strategies and other factors that influence ozone formation in the Denver Metro/North Front Range region.

2017 Sensitivity Modeling Efforts
Several sensitivity modeling analyses were conducted in 2017 looking at various influences on ozone in the nonattainment area.

Moderate Area SIP Modeling Efforts

Base year (2011) and future year (2017) photochemical modeling was required as part of the Moderate Area Ozone nonattainment area SIP.

Previous Control Strategy Evaluation Efforts
In 2011, the RAQC conducted a similar effort to evaluate control strategies. A report was presented to the RAQC Board and is the starting point for this current evaluation effort.

Report from Strategy Subcommittes – Ozone Reduction Measures: Recommendation for Short-Term Actions (Nov. 2011)

Previous control strategy efforts:
Ozone State Implementation Planning: 2010 Progress Report to the Governor (Feb. 2011)
Short-Term Ozone Reduction Strategies (Dec. 2007)