DENVER OZONE MODELING FOR NAAQS ATTAINMENT Ralph Morris Ramboll Environ Acknowledgements: Amanda Brimmer, Ken Lloyd & Jerry Dilley, Denver RAQC Dennis McNally & Cyndi Loomis, Alpine Geophysics Kevin Briggs, Curtis Taipale, Gordon Pierce & Dale Wells, CDPHE Ramboll Environ Staff
OZONE NAAQS AND DENVER NONATTAINMENT AREA 1-Hour Ozone Standard (0.125 ppm) 1982 Ozone Attainment State Implementation Plan (SIP) 1987 Region Attains Standard 2001 Region Designated Attainment/Maintenance Area 1997 -- 8-Hour Ozone Standard (0.08 ppm) 2004 Early Action Compact (EAC) Ozone Action Plan SIP 2006 Revision to EAC Ozone Action Plan SIP 2008 8-Hour Ozone Attainment Plan SIP 2009 Region Attains Standard 2008-12 2015/2020 Ozone Sensitivity Modeling Mar 2008 -- 8-Hour Ozone Standard (0.075 ppm) 2012 Ozone Nonattainment Area Designations Oct 2015 -- 8-Hour Ozone Standard (0.065 0.070 ppm?)
DENVER REGIONAL AIR QUALITY COUNCIL (RAQC) MODELING STUDIES Study Episode Met PGM Grids (km) Future Year 2004 EAC SIP Jun Jul 2002 MM5 CAMx 36/12/4 2007 2008 O3 SIP Jun Jul 2006 MM5 CAMx 36/12/4/(1.33) 2010 2009 2012 May Aug 2008 WRF CAMx 36/12/4 2020* 2016 O3 SIP May Sep 2011 WRF CAMx 36/12/4 2017 2006 episode modeling introduced link based mobile source emissions modeling (CONCEPT) that greatly improved ozone model performance in Denver Better characterization of distribution of Heavy Duty Truck emissions 2008 episode modeling started using WRF & CAMx w/ improved vertical velocity treatment Improved meteorological representation results in improved ozone performance Less transport of ozone from aloft on days without stratospheric intrusion
8-HOUR OZONE TRENDS AND COMPARISONS TO NAAQS 100 8 Hour Ozone (ppb) 95 90 85 80 75 70 65 60 84 83 86 87 81 83 84 1997 8 Hour Ozone Standard <85 ppb 85 82 81 86 82 78 78 82 83 82 2008 8 Hour Ozone Standard 75 ppb Range Proposed by EPA for 2015 Standard Annual 4th Highest Daily Maximu m 8 Hour Ozone (ppb) 3 Year Average 4th Max (Regional Design Value) 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 Year
2002 DENVER OZONE SOURCE APPORTIONMENT MODELING FROM MAY 31, 2004 REPORT Rocky Flat North (RFNO) monitor to northwest of Denver Metropolitan Area (DMA) highest ozone Design Value (DV) 2001 2003 O3 DV = 87 ppb Boundary Conditions (45 ppb) around CONUS domain largest contributor (60%) International/Stratospheric Transport DMA (20 ppb) next largest contributor (27%) On road (13%), non road (7%), Point (5%) http://www.colorado.gov/airquality/tech_doc_repository.aspx?action=open&file=osa.pdf
JUNE-JULY 2006 DENVER OZONE SENSITIVITY TEST MODELING Biogenic (GloBEIS vs. MEGAN) MM5 LSM/PBL (P-X/ACM vs. NOAH/MRF-ETA) Vertical Mixing (OB70 w/ Kv100) BCs (GEOS-Chem vs. MOZART) Mobile Sources (SMOKE-MOBILE6 vs. CONCEPT-MOBILE6 [link-based]) Model Performance Evaluation (O3, NO2, CO, VOC) Run Grids Emissions MM5 Met Kv Profiles Boundary Identifier (km) Biogenic MVVOC LSM PBL Kv Kv_min Conditions Run1.36 36 GloBEIS 1x P-X ACM OB70 Kv100 GEOS-CHEM Run2.36 36 MEGAN 1x P-X ACM OB70 Kv100 GEOS-CHEM Run1.1204 12/4 GloBEIS 1x P-X ACM OB70 Kv100 Run1.36 Run3 4 MEGAN 1x P-X ACM OB70 Kv100 Run1.1204 Run4 4 GloBEIS 1x P-X ACM OB70 0.1 m 2 /s Run1.1204 Run5 4 GloBEIS 1x P-X ACM CMAQ 1.0 m 2 /s Run1.1204 Run6 4 GloBEIS 1x P-X ACM CMAQ Kv100 Run1.1204 Run7 4 GloBEIS 2x P-X ACM OB70 Kv100 Run1.1204 Run8 4 GloBEIS 1x NOAH ETA OB70 Kv100 Run1.1204 Run9 4 GloBEIS 1x NOAH MRF OB70 Kv100 Run1.1204 Run10 4 GloBEIS 3x P-X ACM OB70 KV100 Run1.1204 Run11 36 GloBEIS 1x P-X ACM OB70 KV100 MOZART Run12 1214 GloBEIS 1x P-X ACM OB70 KV100 Run11.36
CAMX 2006 OZONE MODEL PERFORMANCE EVALUATION Able to eliminate ozone hole in Denver
2006 VOC MODEL PERFORMANCE EVALUATION Good VOC performance in downtown Denver (CAMP) VOC underestimation in Weld County 400.00 300.00 200.00 100.00 0.00 Predicted vs. Observed VOC at CAMP Predicted Observed 60616 60619 60622 60625 60628 60701 60704 60707 60710 60713 60716 60719 60722 60725 60728 VOC [ppbc] Date 1200.00 1000.00 800.00 600.00 400.00 200.00 Predicted vs. Observed VOC at Ft Lupton Predicted Observed 0.00 Predicted vs. Observed NOx at CAMP Predicted Observed 200 150 100 50 0 60616 60619 60622 60625 60628 60701 60704 60707 60710 60713 60716 60719 60722 60725 60728 NOx [ppb] 8 10 6 4 2 0 Date Predicted vs. Observed VOC/NOx Ratio at CAMP Predicted Observed 60616 60619 60622 60625 60628 60701 60704 60707 60710 60713 60716 60719 60722 60725 60728 VOC/NOx [ppbc/ppb] 60616 60619 60622 60625 60628 60701 60704 60707 60710 60713 60716 60719 60722 60725 60728 VOC [ppbc] Date Date 2500.00 2000.00 1500.00 1000.00 500.00 0.00 Predicted vs. Observed VOC at Platteville Predicted Observed 60728 60616 60619 60622 60625 60628 60701 60704 60707 60710 60713 60716 60719 60722 60725 VOC [ppbc] Date
INVESTIGATE CAMX 2006 VOC UNDERESTIMATION IN WELD COUNTY Ethane Measurements: Ethane also underestimated Back Trajectories: On days with high VOC underestimation pass over O&G fields CAMx O&G VOC Sensitivity Test: 5 x O&G VOC improves VOC performance in Weld County without degrading performance in Denver Predicted vs. Observed VOC at Ft Lupton Run23 = 5 x O&G VOC Receptor Modeling: Use CMB and PMF w/ VOC observations CAMx VOC Source Apportionment: Emissions based Emissions based source apportionment underestimates O&G VOC contributions compared to measurement based VOC [ppbc] 1200 1000 800 600 400 200 0 6/16 6/19 6/22 6/25 6/28 Observed Run 22 Run 23 7/1/ 7/4/ 7/7/ Date 7/10 7/13 7/16 7/19 7/22 7/25 7/28
RESULTS FROM 2006 EPISODE MODEL SENSITIVITY ANALYSIS In 2011 Denver RAQC buys Optical Gas Imaging (OGI) Camera Found that not all vented gas from Condensate Tanks make it to the flare where VOC is controlled at 98% CDPHE adopts the concept of Capture Efficiency (CE) CE = 0.75 Only75% of the Condensate Tank Flash VOC emissions are controlled For controlled condensate tanks > 10x increase in VOC emissions Results in improved CAMx VOC model performance Perform numerous MM5 (~15) and WRF (~20) meteorological sensitivity tests to determine best performance configuration for simulating ozone with CAMx WRF produces better meteorological performance and, when used with CAMx, better ozone model performance than when MM5 meteorological inputs where used
SENSITIVITY MODELING USING THE MAY-AUG 2008 MODELING EPISODE Much improved ozone performance with WRF, link-based mobile source emissions and O&G capture efficiency July 10, 2008 highest ozone day
CURRENT DENVER OZONE MODELING ACTIVITIES TO ADDRESS THE 2008 OZONE NAAQS (75 PPB) March 2008 new ozone NAAQS of 0.075 ppm (75 ppb) Fourth highest daily maximum 8 hour ozone averaged over 3 years July 20, 2012 Denver/North Front Range designated a Marginal ozone Nonattainment Area (NAAs) June 2013 EPA issues a proposed ozone SIP Requirements Rule in June 2013 Future attainment years: 2015 for Marginal NAAs (based on 2013 2015 observations) 2018 for Moderate NAAs (based on 2016 2018 observations) Marginal NAAs not required to perform ozone modeling for their SIP
RECENT DEVELOPMENTS FOR 2008 OZONE NAAQS December 23, 2014 Based on challenge by environmental groups, DC Circuit Court revokes parts of 2012 Implementation Rule February 13, 2015 EPA updates June 2013 SIP Requirements Rule: Marginal NAA attainment deadline of July 20, 2015: Means a Marginal NAA must attain ozone NAAQS based on 2012 2014 observations (vs. 2013 2015) Attainment deadline of July 20, 2018 for Moderate NAAs Means Moderate NAA must attain based on 2015 2017 observation (vs. 2016 2018) and model attainment year 2017 (vs. 2018)
2014 4 TH HIGHEST DAILY MAXIMUM 8-HOUR OZONE (PPB)
2012-2014 8-HOUR OZONE DEIGN VALUES (PPB)
NEW REQUIREMENTS FOR DENVER/NFR NAA TO ADDRESS MARCH 2008 OZONE NAAQS Based on 2012 2014 observations, Denver/NFR NAA does not attain the ozone NAAQS by June 20, 2015 Marginal attainment date as required Denver/NFR NAA will Bump Up to Moderate NAA by January 2016 New attainment date of June 20, 2018 Need to attain based on 2015 2017 observation data Moderate NAA SIP due 12 18 months after EPA determination SIP and implementation deadlines will be established in EPA rule Moderate Area SIP Requirements Modeled attainment demonstration by 2017 15% Reasonable Further Progress (RFP) (15% VOC reduction 2011 2017) RACT SIP, RACM, I/M, NSR, Contingency Measures
DENVER OZONE SIP MODELING CURRENT STATUS Using WSAQS/3SAQS 2011 modeling platform SMOKE modeling of CDPHE 2011 emissions On road mobile sources: EPA requires MOVES2014 be used. Use local specific (Colorado) fleet distributions and latest CB6 chemistry EPA will not release MOVES2014/CB6 until summer 2011 CAMx base case modeling in summer 2015 2017 preliminary base case modeling by fall 2015 Preliminary 2017 ozone Design Value projections Decide next steps
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