Exceptional Events (EE) Dashboard

What is an Exceptional Event?

Exceptional Events (EEs) are unusual or naturally occurring events that can affect air quality but are not reasonably controllable using techniques that tribal, state or local air agencies may implement in order to attain and maintain the National Ambient Air Quality Standards. Exceptional events may include wildfires, high wind dust events, prescribed fires, stratospheric ozone intrusions, and volcanic and seismic activities.

What is included in an Exceptional Event Demonstration?

Exceptional Events must meet the following criteria, as specified in the federal Exceptional Events Rule (81 FR 68216), before being approved by U.S. EPA:

  1. A narrative, conceptual model describing the event(s);
  2. A demonstration of a clear causal relationship between the event and the measured exceedance(s);
  3. A comparison of the claimed event-influenced concentration(s) to historical concentrations at the same monitoring sites(s);
  4. A demonstration that the event was not reasonably controllable or preventable;
  5. A demonstration that the event was caused by human activity that is unlikely to recur at a particular location OR was a natural event; and
  6. A documentation of the public comment process.
EE NameAction - DateDescription
Exceptional Event Demonstration for PM2.5: June 6 – 8, 2023 and June 29 -30, 2023This demonstration aims to exclude certain PM2.5 monitoring data from June 6 - 8, 2023, and June 29 - 30, 2023, due to the impact of wildfires on New Jersey’s PM2.5 air quality. New Jersey asserts that the specified dates qualify as exceptional events due to the transport of wildfire smoke. The demonstration provides a description of the wildfires, comparison between event concentrations and non-event concentrations, establishment of clear causal relationship, satellite observations, wind trajectory analysis, visual photographic evidence, and a demonstration that the exceptional event was beyond reasonable control or prevention and was a natural occurrence.
Exceptional Event Demonstration Analysis for Ozone During April 13, 2023, June 2, 2023, and June 29 - 30, 2023This demonstration aims to exclude certain ozone monitoring data from April 13, 2023, June 2, 2023, and June 29 - 30, 2023, due to the impact of wildfires on New Jersey’s ozone air quality. New Jersey asserts that the specified dates qualify as exceptional events due to the transport of wildfire smoke, which led to New Jersey exceeding the 2015 70 ppb NAAQS for ozone in the Southern New Jersey portion of the Philadelphia-Wilmington-Atlantic City ozone nonattainment area. The demonstration provides a description of the wildfires, comparison between event concentrations and non-event concentrations, establishment of clear causal relationship, satellite observations, wind trajectory analysis, visual photographic evidence, and a demonstration that the exceptional event was beyond reasonable control or prevention and was a natural occurrence.
Exceptional Event Demonstration Analysis for Ozone During May 25 – 26, 2016This demonstration provides the background, analysis and justification for excluding elevated ozone data collected by NJDEP on May 25 - 26, 2016 from regulatory purposes because they were affected by the emissions from a catastrophic wildfire originating in Fort McMurray, Alberta, Canada.