Region 8

State Implementation Plan (SIP)

This Web page contains information on the EPA-approved State Implementation Plans (SIP) for Colorado, Montana, North Dakota, South Dakota, Utah, and Wyoming. SIPs typically consist of narratives, or rules, or both. Sometimes SIPs include other forms of requirements such as stipulations, agreements, or permits. The states prepare SIPs and submit them to EPA for approval to meet specific requirements of the Clean Air Act, including the requirement to attain and maintain the National Ambient Air Quality Standards (NAAQS). SIP narratives describe how the plan, including any rules or other requirements, will comply with these requirements and maintain the NAAQS. SIP narratives also sometimes include state promises for future action, which we call commitments. Once EPA approves a SIP, EPA and citizens may enforce the SIP rules, requirements, and commitments in Federal court.

This Web page includes the EPA-approved SIP rules and requirements for the listed states, along with SIP commitments.

We also provide links to state Web sites (listed to the right) to enable you to view the current state air quality rules. Please note that the air quality rules on these state Web sites may differ from what is contained in our database. This may happen because a state has yet to submit a rule or rule revision to us for approval, or we have not approved a rule or rule revision that a state has submitted. Without our approval, a state’s change to a rule contained in the EPA-approved SIP has no affect on our or citizens’ authority to enforce the EPA-approved rule in Federal court.


Kathy Ayala, SIP Process Coordinator
1595 Wynkoop Street (8P-AR)
Denver, CO 80202
Phone: (303)312-6142

Monica Morales, Unit Chief, Air Quality Planning Unit
(303) 312-6936