Presentation on theme: "Ozone Exceedances Assessment Department of Environmental Quality 5 Parish Baton Rouge Area Exceedances Occurred on: 8/8/02 9/11/02 4/27/037/18/038/18/03."— Presentation transcript:
Ozone Exceedances Assessment Department of Environmental Quality 5 Parish Baton Rouge Area Exceedances Occurred on: 8/8/02 9/11/02 4/27/037/18/038/18/03 Analysis Presented September 16, 2003 By: Hall Bohlinger, Robert Hannah, James Hazlett, Manop Vanichchagorn & Jennifer Walton
Agenda Welcome Concern over Ozone Exceedances Ozone Exceedance Assessment – Monitored Data – Back Wind Trajectories – Actual Emissions Recent Actions Next Steps
1-hour exceedances occurred at the following monitors in 2002: 1-hour Max, ppb (125 ppb) 8/8/029/11/02 LSU102154 Capitol131164 Port Allen128102 Bayou Plaquemine 66139
1-hour exceedances occurred at the following monitors in 2003: 1-hour Max, ppb (125 ppb) 4/27/037/18/038/18/03 LSU88174108 Capitol78147139 Port Allen81129144 Carville129 74
Recent ozone events occurred on days predicted to be green or low yellow air quality. On 8/18/03 the cloud cover was predicted to be about 65%. Afternoon clouds did not arrive, however, and cloud cover was actually closer to 10%. Ozone events characterized by low wind speed and temperatures in the 90’s. Ozone events appear to be very localized and not regional in nature. While the Baton Rouge Capitol Site is dominated by mobile sources 90% of the time, recent ozone events were preceded by spikes of VOCs not characteristic of mobile sources. Common Factors During Baton Rouge Ozone Episodes
1-hr (ppb) 8-hr (ppb) AM Forecast9170 PM Forecast9170 Maximum Measured Value 174119 Measured values are much higher than predicted values for both 1-hr and 8-hr concentrations. Ozone Forecast for 7/18/03
Ozone Forecast for 8/18/03 1-hr (ppb) 8-hr (ppb) AM Forecast8875 PM Forecast7260 Maximum Measured Value 144112 Measured values are much higher than predicted values for both 1-hr and 8-hr concentrations.
Improving the Understanding of Ozone Episodes Rate of ozone formation characterization Identify VOC species which are the most significant contributors to ozone formation Improve analysis of monitored VOC variability during & preceding episodes Back trajectory analysis to locate possible sources Acquire better understanding of plant-to-plant emissions variability during ozone episodes
NO 2 + hv NO + O O + O 2 O 3 NO + O 3 NO 2 + O 2 How is ozone formed? O 3 + hv O 2 + OO + H 2 O 2 OH OH + O 2 + RH RO 2 + H 2 ORO 2 + NO RO + NO 2 Reactive VOCs interact with hydroxyl radicals to convert NO to NO 2 The outcome of these reactions is the additional NO 2 formed photolizes producing more ozone – less NO is available to scavenge the ozone RO + O 2 HRHO + HO 2 HO 2 + NO NO 2 + OH
Rate of Ozone Formation: In the hour preceding exceedances 10-15 ppb/hr = typical> 40 ppb/hr = rapid ozone formation
Port Allen Site 7/18/2003 11:00-12:00 = 50 ppb ozone increase 9:00-10:00 = 50 ppb ozone increase 1 hr stnd - 125 ppb
Most Abundant VOC Species Identified at BR Capitol Site ( Top 10 Represent 48% of Total VOC) propane n-butane ethane isopentane (2-methylbutane ) ethylene isobutane (2-methylpropane) propylene n-pentane toluene n-hexane Ranked by abundance in ppbc
The incremental reactivity characterizes the ozone formation potential of a VOC specie and all of its reaction products. VOC SpecieMaximum Incremental Reactivity (MIR) methane 0.005 mol Ozone/mol C propylene 2.750 mol Ozone/mol C butane 0.310 mol Ozone/mol C benzene 0.110 mol Ozone/mol C ethane 0.080 mol Ozone/mol C propane 0.150 mol Ozone/mol C isoprene 2.580 mol Ozone/mol C ethylene 2.160 mol Ozone/mol C toluene 0.740 mol Ozone/mol C Isopentane 0.410 mol Ozone/mol C
VOC Species at BR Capitol Site Ranked by Ozone Forming Potential ( Top 10 Represent 95% of Total Reactivity) ethylene propylene isoprene m/p-xylene 1-butene n-butane isopentane (2-methylbutane ) toluene o-xylene isobutane (2-methylpropane) Ranked by abundance in ppbc * MIR Red indicates HRVOC species with recently lowered RQ.
VOC Diurnal Profiles Typically VOC concentrations peak during 6-9am period and reach lowest levels during late afternoon hours.
The ozone event on 7/18/2003 was preceded by above normal spikes of VOCs. Capitol Site 3:00 pm exceedance 147ppb
Note the peaks in VOC concentration throughout the ozone exceedance.
The ozone event on 8/18/2003 was also preceded by above normal spikes of VOCs. Capitol Site 2:00 pm exceedance 139 ppb
Analysis of VOC Profiles The Hydrocarbon Profile (fingerprint) of Capitol Site is usually very consistent and dominated by mobile source emissions, particularly during the morning rush hour (6-9am). An analysis of peak concentrations observed before & during ozone events has indicated sources of VOC’s other than mobile. The Capitol site 6-9am sample on 8/17/03 showed impact of source very similar to evaporative gasoline. A sample collected just 3 hours later shows entirely different source domination in the VOC profile. Profile dominated by very light VOCs including the highly reactive species, ethylene & propylene.
Normal mobile-dominated source profile versus profile of sample containing above normal amounts of HRVOC’s Isobutane Ethylene Propane Propylene
Southern University Site detects frequent hits of industrial emissions. Continuous VOC monitor triggers canister collection during periods of above normal VOC concentrations. Sampler has triggered 43 times so far during 2003. Multiple VOC profiles have been observed. Total VOC concentrations up to nearly 7 ppm have been observed with hits of MTBE hits up to 400 ppbv. Concentrations of highly reactive VOCs, ethylene & propylene, commonly observed in the 30 – 60 ppbc range.
The night before the July 18 th ozone event, the Southern monitor was triggered by a source contributing ethylene & isobutane. Isobutane Ethylene
The capitol site sample preceding 8/18/03 ozone event & Southern spike sample preceding 7/18/03 ozone event appear to have been impacted by the same source emitting primarily ethylene & isobutane. Isobutane Ethylene
An analysis of the wind direction when ethylene/propylene spikes occur indicates two local sources – one source to the north-northeast of the site and a second source to the northwest of the site.
The south Scotlandville event monitor is triggered less often but indicates a source to the south with another possible source north to northeast of the site.
BTR Ozone History & Progress In Nov. 1990, BTR was designated as a serious ozone non-attainment area. The attainment date was set for Nov. 1999. The first Ozone Task Force was formed. Rate of Progress commitments were made to reduce VOC emissions - 15% by 1994; 9% by 1996 Despite progress in reducing emissions and the number of exceedance days, BTR failed to meet the Nov. 1999 attainment date. The second Ozone Task Force convened. Effective June 23, 2003, the BTR area was bumped up to a severe ozone non-attainment classification.
Approx tons:1990 = 39,0002002 = 13,000 67% Reduction 5 Parish Baton Rouge Area Point Source VOC Emissions
Approx tons:1990 = 66,7002002 = 42,300 37% Reduction 5 Parish Baton Rouge Area Point Source NOx Emissions
Consequences of the Exceedances: Continued Non-Attainment No chance for attainment with the 1 hour standard for 2003 or 2004 Attainment date is 2005 Severe non-attainment designation remains – RFG – Offsets – increased to 1.3 to 1 – Redefinition of Major Source – lowered to 25 tpy – Penalty Fees?
Consequences of Continued Non-Attainment & Severe Status: Penalty Fees CAA Section 185 requires the assessment of penalty fees on facilities in an area designated as severe if the area fails to reach attainment by 2005. Fees are assessed for each ton of NOx and VOC emissions in excess of 80% of the source’s baseline amount. Fee is equal to $5000 per ton plus an annual CPI adjustment; predicted to be $7500 per ton. Based on actual 2002 emissions, annual fees for some local companies will likely equal (in millions): – Dow - $14.8Shell Chem. - $1.9PCS - $2 – Exxon Chem. - $6.3Exxon Ref. - $7.9Placid - $1.8
Recent Actions Emergency rule to lower HRVOC RQs – Effective 8/12/03 – 18 of 20 notices received as a result of emergency rule Administrative Order – 9/3/03 – Maintain and submit HRVOC data by 10/3/03 Additional monitoring – Speciated VOC event monitors added at Capitol, Port Allen, LSU and Carville Discussions with EPA on collaborative effort to study BTR’s ozone exceedances
Next Steps Permanent rule to lower HRVOC RQs Required speciation of HRVOCs in permits – Ethylene, propylene & butenes Debate with EPA over Interprecursor Trading Form Ozone Technical Committee - Convene by October – Evaluate additional data collected (Monitors, RQ’s & AO) – Design studies and determine needed resources by 12/03 – Oversee contracted research projects to begin by 5/1/04 and be complete by 11/04 – Recommend control strategies, if needed Form Ozone Steering Committee - Convene by October – Secure funding for research
For more information… James Hazlett – 225-219-3554 Manop Vanichchagorn – 225-219-3489 Jennifer Walton – 225-219-3486 LDEQ Ozone Website – http://www.deq.state.la.us/evaluation/ozone/index.htm