Missoula City-County Health Department COVID-19 Information

Joint Information Center: Community COVID-19 Information and Resources

Information on Missoula County offices reopening to the public Monday, June 1

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Missoula has had a history of violating the federal carbon monoxide (CO) standard. The first recorded violations were in 1977. Once designated as a non-attainment area by the EPA, the department had to write a State Implementation Plan (known as a SIP) detailing how Missoula would attain and then maintain pollution levels below the federal standards.

Thanks to fleet improvements, the introduction of oxyfuels in the winter, and various woodstove programs, Missoula has not exceeded the federal CO standard since 1991.

Missoula was redesignated as in attainment for carbon monoxide in 2007, and we are now a maintenance area for that pollutant.  As part of the redesignation process, Missoula is now required to submit a second 10-year maintenance plan to the EPA for incorporation into the SIP.

The Missoula City-County Air Pollution Control Board held a public hearing on May 19, 2016 at the Missoula City-County Health Department to take public comment on the proposed Missoula County Carbon Monoxide (CO) Second 10-Year Limited Maintenance Plan (LMP) and its incorporation into the Montana State Implementation Plan. The Air Pollution Control Board approved the LMP at the May 19th meeting.  Following consultation and resolutions of support from the city, county and MPO, the LMP was forwarded to the Montana Department of Environmental Quality and Governor's Office for submittal to the EPA

You may review the Missoula County Carbon Monoxide Second 10-Year Limited Maintenance Plan by clicking on the links below.  A copy is also available at the Missoula City-County Health Department, 301 W. Alder St, Missoula, MT 59802.

 Missoula County Carbon Monoxide Second 10-Year Limited Maintenance Plan

Appendix A: Limited Maintenance Plan Option

Appendix B: Maps - Maintenance Area, Missoula City Limits, Air Stagnation Zone

Appendix C: Missoula 2010 Carbon Monoxide Emission Inventory

Appendix C-1: Map of Missoula CO Maintenance Area

Appendix C-2: Map of Missoula City Limits

Appendix C-3: MOVES2014 Fuel Formation for the Missoula CO Maintenance Area

Appendix C-4: MOVES2014 CO Maintenance Area Run Specification File

Appendix C-5: Quality Assurance Plan for the 2010 Carbon Monoxide Inventory in support of Missoula County's 2nd 10-Year Limited Maintenance Plan for the Carbon Monoxide Maintenance Area

Appendix C-5(a): Map of CO Maintenance Area

Appendix C-5(b): Map of Missoula City Limits

Appendix C-6: Data and Supporting Documents (available at MCCHD)

Appendix D: Local Record of Adoption (to be completed)