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Baton Rouge Ozone: Cause & Effect A look into the Five Parish Baton Rouge Area Ozone Exceedances. October 2, 2003. Agenda. Welcome Concern over Ozone Exceedances Ozone Exceedance Assessment Monitored Data Actual Emissions Recent Actions Next Steps. BTR Ozone History & Progress.
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Baton Rouge Ozone: Cause & EffectA look into the Five Parish Baton Rouge Area Ozone Exceedances October 2, 2003
Agenda • Welcome • Concern over Ozone Exceedances • Ozone Exceedance Assessment • Monitored Data • Actual Emissions • Recent Actions • Next Steps
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.
5 Parish Baton Rouge Area Point Source VOC Emissions Approx tons: 1990 = 39,000 2002 = 13,000 67% Reduction
5 Parish Baton Rouge Area Point Source NOx Emissions Approx tons: 1990 = 66,700 2002 = 42,300 37% Reduction
8-hr Exceedances/Design Values 85 ppb standard
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 - $14.8 Shell Chem. - $1.9 PCS - $2 • Exxon Chem. - $6.3 Exxon Ref. - $7.9 Placid - $1.8
Ozone Exceedance Assessment Jim Hazlett
1-hour exceedances occurred at the following monitors in 2002: 1-hour Max, ppb (Standard = 125 ppb)
1-hour exceedances occurred at the following monitors in 2003: 1-hour Max, ppb (Standard = 125 ppb)
Common Factors During Baton Rouge Ozone Episodes • 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 except for Sept 19th ( 84º). • Most of the 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.
Localized Episode April 27th Exceedance at Carville 1 hr stnd - 125 ppb
Ozone Forecast for 7/18/03 • Measured values are much higher than predicted values for both 1-hr and 8-hr concentrations.
Ozone Forecast for 8/18/03 • 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
How is ozone formed? O + O2 O3 NO2 + hv NO + O NO + O3 NO2 + O2 Reactive VOCs interact with hydroxyl radicals to convert NO to NO2 O3 + hv O2 + O O + H2O 2 OH OH + O2 + RH RO2 + H2O RO2 + NO RO + NO2 RO + O2 HRHO + HO2 HO2 + NO NO2 + OH The outcome of these reactions is the additional NO2 formed photolizes producing more ozone – less NO is available to scavenge the ozone
Rate of Ozone Formation:In the hour preceding exceedances 10-15 ppb/hr = typical > 40 ppb/hr = rapid ozone formation
The July 18th event showed very rapid buildup of ozone at Capitol, Port Allen & LSU. 1 hr stnd - 125 ppb
Capitol Site 7/18/2003 1 hr stnd - 125 ppb 12:00-1:00 = 60 ppb ozone increase
Port Allen Site 7/18/2003 1 hr stnd - 125 ppb 11:00-12:00 = 50 ppb ozone increase 9:00-10:00 = 50 ppb ozone increase
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 Species at BR Capitol SiteRanked 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.
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.
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
Normal mobile-dominated source profile versus profile of sample containing above normal amounts of HRVOC’s Isobutane Ethylene Propane Propylene
The ozone event on 9/19/2003 was preceded by a large above normal spike of VOCs. Bayou Plaq. 12:00 pm exceedance 126 ppb
The ozone event on 9/19/2003 was preceded by a long duration above normal spike of VOCs. Exceedances: 12:00 Bayou Plaq. – 126ppb 1:00 LSU – 129ppb
Normal mobile-dominated source profile versus profile of sample containing above normal amounts of HRVOC’s 1,3-butadiene Ethylene Propylene Isobutane
Hour preceding exceedance dominated by above normal amounts of HRVOC’s Ethylene Ethane Isobutane
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 18th 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
Isobutane Propane Propylene Ethylene
Wind Direction Analysis 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.
Wind Direction Analysis 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.
Iberville Ascension East BTR West BTR
Recent Actions & Next Steps Hall Bohlinger
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 • Form HRVOC 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