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Archive by tag: Significant Impact Levels for Ozone and Fine ParticlesReturn
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DNR to Delay Implementation of Revised PM2.5 SILs

DNR to Delay Implementation of Revised PM2.5 SILs

  • 7/30/2018 8:29:00 AM
  • View Count 1088
On April 17, 2018 EPA released a memo titled “Guidance on Significant Impact Levels for Ozone and Fine Particles in the Prevention of Significant Deterioration Permitting Program.” In this guidance EPA recommended a 24-hour significant impact level (SIL) of 1.2 µg/m3 for particulate matter less than or equal to 2.5 microns in diameter (PM2.5), which is the same level as the previously proposed draft SIL