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Home My WebLink AboutMemo - Mail Packet - 4/24/2018 - Information From Gerry Horak Re: Colorado Department Of Health And Environment Re: Wildfire-Influenced Ozone Exceptional Events September 2 And 4, 2017Wildfire-influenced Ozone Exceptional Events September 2 and 4, 2017 RAQC Board Meeting April 6, 2018 April 19, 2018 TO: Mayor & City Councilmembers FROM: Gerry Horak Per April 16 LPT Minutes /sek What will be discussed?  What are exceptional events?  Exceptional events rule  Reasons for submitting exceptional events  History of exceptional event submissions in Colorado  Other agency exceptional events  Ozone exceptional events on September 2 and 4, 2017 2 What are exceptional events?  Per the U.S. Environmental Protection Agency (EPA) in 40 CFR 50.1:  Exceptional event means an event(s) and its resulting emissions that affect air quality in such a way that there exists a clear causal relationship between the specific event(s) and the monitored exceedance(s) or violation(s), is not reasonably controllable or preventable, is an event(s) caused by human activity that is unlikely to recur at a particular location or a natural event(s), and is determined by the Administrator in accordance with 40 CFR 50.14 to be an exceptional event. It does not include air pollution relating to source noncompliance. Stagnation of air masses and meteorological inversions do not directly cause pollutant emissions and are not exceptional events. Meteorological events involving high temperatures or lack of precipitation (i.e., severe, extreme or exceptional drought) also do not directly cause pollutant emissions and are not considered exceptional events. However, conditions involving high temperatures or lack of precipitation may promote occurrences of particular types of exceptional events, such as wildfires or high wind events, which do directly cause emissions.  Natural event means an event and its resulting emissions, which may recur at the same location, in which human activity plays little or no direct causal role. For purposes of the definition of a natural event, anthropogenic sources that are reasonably controlled shall be considered to not play a direct role in causing emissions. 3 Reasons for submitting exceptional events  Primarily used to exclude data from use in National Ambient Air Quality Standard determinations  Avoids using high data values over which an area has no control  Avoids unwarranted non-attainment designations  Also used to inform local agencies and the general public of reasons for high data values  Assists in local planning efforts  Must have regulatory significance for EPA to exclude  Initial area designations  Area redesignations  Area classifications  Attainment determinations (including clean data determinations)  Attainment date extensions  Findings of State Implementation Plan (SIP) inadequacy leading to a SIP call  Other actions on a case-by-case basis as determined by the Administrator  If no regulatory significance, EPA will issue a letter stating that at this time they are taking no action 4 For these events, the regulatory significance is that these ozone values would prevent a “clean data year” and the area could be reclassified to “serious” Exceptional event documents  40 CFR 50.14 Treatment of air quality monitoring data influenced by exceptional events (updated Oct. 2016)  A State, federal land manager or other federal agency may request the Administrator to exclude data showing exceedances or violations of any national ambient air quality standard that are directly due to an exceptional event from use in determinations identified in paragraph (a)(1)(i) of this section by demonstrating to the Administrator’s satisfaction that such event caused a specific air pollution concentration at a particular air quality monitoring location.  40CFR 51.930 Mitigation of Exceptional Events (updated Oct. 2016)  A State requesting to exclude air quality data due to exceptional events must take appropriate and reasonable actions to protect public health from exceedances or violations of the national ambient air quality standards.  Guidance on the Preparation of Exceptional Events Demonstrations for Wildfire Events that May Influence Ozone Concentrations (Sept. 2016)  https://www.epa.gov/air-quality-analysis/treatment-air-quality-data- influenced-exceptional-events 5 40 CFR 50.14 Treatment of air quality monitoring data influenced by exceptional events  Specific types of exceptional events listed  Fireworks displays; Prescribed fires; Wildfires; High wind dust events; Stratospheric intrusions  Specific elements that must be addressed  (A) A narrative conceptual model that describes the event(s) causing the exceedance or violation and a discussion of how emissions from the event(s) led to the exceedance or violation at the affected monitor(s);  (B) A demonstration that the event affected air quality in such a way that there exists a clear causal relationship between the specific event and the monitored exceedance or violation;  (C) Analyses comparing the claimed event-influenced concentration(s) to concentrations at the same monitoring site at other times to support the requirement at paragraph (c)(3)(iv)(B) of this section;  (D) A demonstration that the event was both not reasonably controllable and not reasonably preventable; and  (E) A demonstration that the event was a human activity that is unlikely to recur at a particular location or was a natural event. 6 Guidance on the Preparation of Exceptional Events Demonstrations for Wildfire Events that May Influence Ozone Concentrations  The EPA developed this document to assist air agencies preparing exceptional events demonstrations for wildfire influences on O3 concentrations that meet the requirements of CAA section 319(b) and the Exceptional Events Rule.  1) A narrative conceptual model that describes the event(s) causing the exceedance or violation and a discussion of how emissions from the event(s) led to the exceedance or violation at the affected monitor(s)  2) A demonstration that the event affected air quality in such a way that there exists a clear causal relationship between the specific event and the monitored exceedance or violation  3) Analyses comparing the claimed event-influenced concentration(s) to concentrations at the same monitoring site at other times. The Administrator shall not require a State to prove a specific percentile point in the distribution of data  4) A demonstration that the event was both not reasonably controllable and not reasonably 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  6) Documentation that the submitting air agency followed the public comment process 7 Wildfire-influenced ozone  2016 Exceptional Event Revisions include Guidance for Ozone Exceedances due to the presence of Wildfire Smoke  Agencies must demonstrate a Clear Causal Relationship through technical analysis of the event and the monitored exceedance  3 tiers in guidance document 8 Tier 1 Tier 2 Tier 3 Wildfires that clearly influence monitored O3 exceedances or violations when they occur in an area that typically experiences lower O3 concentrations. This tier is associated with an O3 concentration that is clearly higher than non-event related concentrations, or occur outside of the area’s normal O3 season. The wildfire event’s O3 influences are higher than non- event related concentrations, and fire emissions compared to the fire’s distance from the affected monitor indicate a clear causal relationship. The wildfire does not fall into the specific scenarios that qualify for Tier 1 or Tier 2, but the clear causal relationship criterion can still be satisfied by a weight of evidence showing. Exceptional Event Tier 2 Analysis Key Factor #1: Fire emissions (Q) compared to distance (D): ࡽ ࡰ ൒૚૙૙ ࢚࢕࢔࢙ ࢖ࢋ࢘ ࢊࢇ࢟ ࢑࢓ ܳ ൌ ݁݉݅ ݕ ܽ݀ ݎ ݁݌ ݏ ݊݋ ݐ ݏ ݊݋݅ ݏ ݏൌ ܸܱ ܱܰ ൅ ܥ௫ Aggregating Multiple Fires: emissions weighted distance (3 fire example) ௜௠௘ ܦ௦௦௜௢௡௦ ௪௘௜௚௛௧௘ௗ ൌ ௘௥௜௙ ܦ భܳ௙௜௥௘ భ ൅ ௘௥௜௙ ܦ మܳ௙௜௥௘ మ ൅ ௘௥௜௙ ܦ యܳ௙௜௥௘ య ܳ௙௜௥௘ భ ൅ܳ௙௜௥௘ మ ൅ܳ௙௜௥௘ య ܳ௦௨௠ ௜௠௘ ܦ௦௦௜௢௡௦ ௪௘௜௚௛௧௘ௗ ൌ ∑ܳൌܳ௙௜௥௘ భ ൅ܳ௙௜௥௘ మ ൅ܳ௙௜௥௘ య ௘௥௜௙ ܦ భܳ௙௜௥௘ భ ൅ ௘௥௜௙ ܦ మܳ௙௜௥௘ మ ൅ ௘௥௜௙ ܦ యܳ௙௜௥௘ య ܳ௙௜௥௘ భ ൅ܳ௙௜௥௘ మ ൅ܳ௙௜௥௘ య ൒ 100 ݉݇/݀݌ ݐ Key Factor #2: Historical Comparison • Event is in the 99th or higher percentile of 5-year distribution of O3 data • Event is one of the four highest O3 concentrations within 1 year 9 Process for submitting exceptional events  Provide initial notification to EPA  Place qualifier flag on data in AQS  Informational  Request Exclusion  Develop technical support document  Provide a 30-day public comment period  Submit document to EPA  Must include responses to comments  EPA will concur, deny or take no action 10 Colorado exceptional event submissions  Primarily for high winds/blowing dust  2008 – 2015  46 events submitted to EPA  2 not concurred on by EPA as had no regulatory significance (+ one expected)  Remainder concurred on by EPA  Generally in Southern Colorado  Lamar, Alamosa, Pagosa Springs, Durango, Crested Butte, Telluride, Grand Junction  One for stratospheric ozone  2010  Not concurred on by EPA as had no regulatory significance  Two for wildfire-influenced ozone  September 2 and 4, 2017  To be submitted to EPA after public comment period 11 Other wildfire-influenced ozone exceptional event submissions  Washoe County (Reno), NV  August 21, 2015 due to California wildfires  July 2 – 4, 2016 due to California wildfire  Connecticut  May 25 – 26, 2016 due to Canadian wildfires  Massachusetts  May 25 – 26, 2016 due to Canadian wildfires  New Jersey  May 25 – 26, 2016 due to Canadian wildfires  Rhode Island  May 25 – 26, 2016 due to Canadian wildfires 12 All have been concurred upon by EPA Note: None had Q/D > 100 Labor Day 2017 Weekend Smoke Sept. 2nd, 2017 @ 4 PM Sept. 4th, 2017 @ 4 PM 13 Labor Day Weekend Ozone Rocky Flats NREL Welch Chatfield Max. 8 hr O3 Sept. 2nd, 2017 Rocky Flats NREL Welch Chatfield Max. 8 hr O3 Sept. 4th, 2017 14 Labor Day Weekend Ozone Rocky Flats NREL Welch Chatfield Max. 8 hr O3 Sept. 2nd, 2017 Rocky Flats NREL Welch Chatfield Max. 8 hr O3 Sept. 4th, 2017 15 Site Highland Chatfield Welch Rocky Flats NREL Aspen Park 9/2/2017 70 ppm 71 ppm 75 ppm 71 ppm 76 ppm 56 ppm 9/4/2017 71 ppm 73 ppm 74 ppm 78 ppm 76 ppm 72 ppm 70 ppm 2015-NAAQS 75 ppm 2008-NAAQS Observed Minute O3 9/2: Prolonged high O3 period with some sharp jumps when smoke plumes reached sites 16 9/4: Huge ozone jumps when smoke plumes reached sites Observed O3 and PM2.5 9/2: Prolonged high O3 period with corresponding PM2.5 9/4: O3 spike across multiple monitors and very high PM2.5 17 Wildfire Summary Prolonged hot and dry conditions created a volatile environment for wildfire-prone forests in Pacific Northwest and Northern Rockies Precipitation and temperature trends in August 2017 (the month prior to the event) 18 Wildfire Summary Prolonged hot and dry conditions created a volatile environment for wildfire-prone forests in Pacific Northwest and Northern Rockies USDA Drought Monitor: - Abnormally Dry in Pacific Northwest - Exceptional Drought in Northern Rockies 19 Wildfire & Smoke Observations: Sept 1st MODIS Terra True Color Satellite with HMS Fire detection @ 5 PM on 9/1/2017 20 Wildfire & Smoke Observations: Sept 2nd MODIS Terra True Color Satellite with HMS Fire detection @ 5 PM on 9/2/2017 21 Wildfire & Smoke Observations: Sept 3rd MODIS Terra True Color Satellite with HMS Fire detection @ 5 PM on 9/3/2017 22 Wildfire & Smoke Observations: Sept 4th MODIS Terra True Color Satellite with HMS Fire detection @ 5 PM on 9/4/2017 23