Cache Valley Fine Particulate Matter Maintenance Plan
Background
Franklin County, Idaho was designated as part of the multi-state Logan, Utah-Idaho nonattainment area for the 2006 PM2.5 standard, effective December 14, 2009 (74 FR 58688, published November 13, 2009). The nonattainment area is also known colloquially as the Cache Valley.
To meet the planning obligations for the Idaho portion of the nonattainment area, Idaho submitted state implementation plan revisions to the EPA on December 14, 2012, December 24, 2014, March 20, 2018, and July 31, 2019.
The EPA approved the plan revisions in a series of actions on March 25, 2014 (79 FR 16201 (pdf) (238 KB)), July 18, 2014 (79 FR 41904 (pdf) (233 KB)), January 4, 2017 (82 FR 729 (pdf) (270 KB)), August 8, 2017 (82 FR 37025 (pdf) (249 KB)), August 20, 2018 (83 FR 42033) (pdf) (249 KB)), and February 20, 2020 (85 FR 9664).
On September 13, 2019, Idaho submitted a maintenance plan for the Franklin County portion of the Cache Valley, demonstrating continued compliance with the 2006 PM2.5 NAAQS through 2031. Idaho requested the EPA approve the maintenance plan and redesignate the area to attainment.
On May 21, 2021, the EPA approved the submitted maintenance plan and redesignated the Idaho portion of the Logan, Utah-Idaho nonattainment area to attainment, effective June 21, 2021 (86 FR 27532) (pdf) (265 KB)).
Summary
The plan relies on measures to control emissions from residential wood combustion and road dust and a contingency plan to be implemented if ambient air exceeds the 2006 PM2.5 standard.
Rules
- City of Clifton Ordinance No. 120, August 11, 2012
- City of Dayton Ordinance #287, August 8, 2012
- Franklin City Ordinance No. 2012-9-12, Solid Fuel Heating Appliances, September 12, 2012
- Franklin County Ordinance No. 2012-6-25, Solid Fuel Heating Appliances, June 25, 2012
- City of Oxford Memorandum of Understanding, Solid Fuel Heating Appliances, October 22, 2012
- City of Preston Ordinance No. 2012-1, June 11, 2012
- City of Weston Ordinance No 2012-01, August 1, 2012
Other Control Measures
- Letter of Intent PM2.5 Reduction, Franklin County Road Department to Department of Environmental Quality (Voluntary Measure), July 16, 2012
- Road Sanding Agreement, Idaho Transportation Department to Idaho Department of Environmental Quality (Voluntary Measure), October 25, 2012
Contingency Plan
- The contingency plan for the area is to be implemented as expeditiously as practicable but no later than 18 months after an exceedance of a warning or action level as specified in the plan.
- If the contingency plan is triggered, Idaho will evaluate potential contingency measures including but not limited to further curtailing residential wood combustion and reducing emissions from on-road and non-road vehicles and industrial sources.
EPA Effective Date
June 21, 2021