EE Events for EPA Region

From Earth Science Information Partners (ESIP)

Exceptional Events by EPA Region

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This is not an official list of exceptional events

A goal of this wiki space is to provide a forum for illustrating Exceptional Events as defined the the EE Rule. For the illustrations, specific events need to be selected that are both illustrative and relevant. This page contains an evolving list of candidate air qualitiy events that may have characteristics of Exceptional Events as defined the the EE Rule. Some of the listed events have already been handled by the regulatory process.

Events in Region 1


Events in Region 2


Events in Region 3


Events in Region 4


In the prepapratory phases of the EE Rule, considerable analyses were conducted to evaluate a list candidate exceptional events submitted by the States GA/TN and SC. All the requested exemptions were attributed to smoke impacts. These analyses, conducted by Husar et. al.(2005), were incuded in the Docket of the EE Rule.

Events in Region 5


Events in Region 6

Contacts: The principal contact for this in Region 6 is Jim Afghani

The Texas Commisssion of Environmental Quality is maintaining a comprehensive list of air pollution events occurring in Texas. The event documentation begun in 2000 and include ozone, fire as well as dust events from local (TX/NM/Mexico) and distant (Sahara) sources. There is extensive documentation provided from satellite (incl. animations) and surface pollutant monitors, wether data, webcams and other data sources. The Texas collection is an outstanding, rich resource for event selection.

Candidate events from New Mexico.

Events in Region 7


Events in Region 8


April 15, 2002: Exceptionally high wind PM events April 15, 2002 (power went out at all Utah monitors before a complete sampling run could complete except Lindon, Utah (49-049-4001). Peak hourly average winds at the monitor were 18 knots, but area winds may have reached 60 mph at other sites. The PM monitor (PM2.5?) recorded 288 mg/m3.

  • April 1, 2003: Monitors in Salt Lake City recorded as follows: 49-035-0012 358 mg/m3, 49-035-1001 421 mg/m3, 49-035-3006 360 mg/m3
  • April 2, 2003: 49-035-0012 209 mg/m3, 49-035-1001 No sample (1 in 3), 49-035-3006 120 mg/m3

Of particular interest in this one would be reasons why 49-035-0012 and 49-035-3006 were nearly identical on April 1, but quite different on April 2. Winds on these days were on the order of 30 knots hourly average, with gusts up to 50 or 60 mph.

July 26, 2006: Monitor 49-035-0012 recorded 164 mg/m3, was flagged as a high wind day. Only this monitor in north Salt Lake City had an exceedance or a flag; the State identified microbursts in the area due to a line of thunderstorms as the culprit. Salt Lake International Airport recorded a peak gust of 53 mph and peak 2 minute winds of 44 mph 3.4 miles west of the monitor. This might be good to look at shorter averaging times than for the large frontal passage sustained winds of the previous two examples.

Potential smoke impacts to ozone.

Events in Region 9


Southern California: A PM10 series of wildfires events to use involves the following sites in 10/2003:

Calexico - Ethel Street (06-025-0005)  10/24/03 and 10/30/03
Calexico - Grant Street  (06-025-0004) 10/24/03
El Centro - 9th Street  (06-025-1003)  10/30/03
Brawley - Main Stree  (06-025-0003     10/30/03
Westmoreland  (06-025-4003)            10/30/03
Niland  (06-025-4004)                  10/30/03
Escondido  (06-073-1002)         10/29/03
El Cajon  (06-073-0003)          11/23/03
San Diego  (06-073-0006)         11/23/03
Victorville  (06-071-0306)       10/30/03
Rubidoux  (06-065-8001)          10/27/03

Example from BAAQMD: On Sept 30, 1999 there was a N. California fire event that potentially drove the Concord and Fairfield monitoring sites above the 8-hr ozone standard - see all the final ozone numbers at BAAQMD and met data. Substantial analysis was done on this event because it didn't fit the normal exceedance pattern. For example, the Suisun met station only got up to 92°F during the nearby Fairfield exceedance and all northern sites were unusually elevated.

Examples from Arizona:

Events in Region 10


Three examples of high wind events in Region 10. The documentation is below: