4 The record articles

Sulfur Dioxide (SO2) Data Requirements Rule (DRR): The Final Rule

Posted: August 19th, 2015

Authors: Colin M. 

On August 10, 2015, the U.S. Environmental Protection Agency (U.S. EPA) submitted the final version of the DRR (40 CFR Part 51, Subpart BB) for the 2010 one (1)-hour sulfur dioxide (SO2) National Ambient Air Quality Standards (NAAQS). The final rule looks pretty familiar (if you need a refresher check out Colin and Frank’s articles), but there are a few changes worth noting:

  1. Agencies must identify sources in their jurisdictions that have SO2 emissions greater than 2,000 tons per year (tpy) during the most recent year for which emissions data are available. The rule no longer contains applicability criteria based on other emissions thresholds or populations in a given area.
  2. Agencies now have three (3) options to characterize air quality:
    a. Air quality modeling,
    b. Ambient monitoring, or
    c. Establishing enforceable permit limits to keep the source(s) below the
    2000 tpy threshold
  3. Agencies must identify the approach to be used for affected sources by July 1, 2016
  4. For sources using the modeling approach, a protocol must be provided to U.S. EPA by July 1, 2016, and submit modeling analyses by January 13, 2017
  5. For sources using the monitoring approach, monitors must be installed and operational by January 1, 2017
  6. For sources electing to take a limit, the limit must be adopted and effective by January 13, 2017

ALL4 currently is assisting several clients with DRR evaluations and would be happy to assist you in evaluating and implementing your compliance approach. Feel free to contact Colin McCall at (678) 460-0324 x206 with questions.


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