• District Rule 4352
    Solid Fuel-Fired Boilers, Steam Generators, and Process Heaters

Summary of Rule Amendment Efforts

Rules 4352 controls emissions from boilers, steam generators, and boilers fired on a variety of solid fuels:  coal, petroleum coke, biomass, tire-derived fuel, and municipal solid waste (MSW).  Although the output from units subject to the rule could be utilized in many settings, all of the operators within the San Joaquin Valley use the output from the units to generate electricity.  There are 7 units currently active in the Valley at 6 facilities.  These units are fired exclusively on MSW or biomass.

On December 16, 2021, the District Governing Board adopted amendments to Rule 4352 to include even more stringent NOx emission limits for solid fuel fired boilers, steam generators, and process heaters operating in the Valley, as well as establishing PM, and SOx emission limits.  The adopted regulatory amendments satisfy the District's control measure commitment in the District's 2018 PM2.5 Plan, to support expeditious attainment of the health-based federal PM2.5 and ozone air quality standards.  In addition, the amendments address commitments included in Board/CARB-approved South Central Fresno and Stockton Community Emissions Reduction Programs developed through the AB 617 community engagement process.

District Contact

Recent and Upcoming Public Workshops

Date & Time Notice Materials
Thursday, December 16th, 2021 at 9:00AM

Notice of Public Hearing


Board Item

Final Rule

Thursday, November 4th, 2021 at 1:30PM

Notice of Public Workshop

Notice of Draft Rule Documents Available for Review


Draft Rule

Thursday, September 30th, 2021 at 2:00PM Notice of Public Workshop Presentation
Thursday, December 3rd, 2020 at 4:00PM Notice of Scoping Meeting Presentation