estimating secondary pollutant impacts from single sources · estimating secondary pollutant...

Estimating Secondary Pollutant Impacts from Single Sources

Kirk Baker

4/27/2012 1All material shown is preliminary

NoteNote

• All information presented is consideredAll information presented is considered preliminary by the U.S. EPA and provided to describe and illustrate potential approachesdescribe and illustrate potential approaches and complex ideas

• This work is evolving and we are continuing to• This work is evolving and we are continuing to learn and improve these techniques so some or all of the information presented in thisor all of the information presented in this presentation may change


Fine Scale/Single Source ModelingFine Scale/Single Source Modeling

• Table below shows model scales, application types, and example models currently used for these needs (not all models shown)

• Evaluate models consistently against available observation data and in the context the models will be applied

Application type and scaleSO2, NO2,

Primary PM2.5Secondary PM2.5 OzoneApplication type and scale Primary PM2.5 PM2.5 Ozone

Single source fenceline AERMODSingle source urban scale AERMODHybid single source/all sources "hot spot" analysisAll sources urban scale CAMx CMAQ CAMx CMAQ CAMx CMAQAll sources urban scale CAMx, CMAQ CAMx, CMAQ CAMx, CMAQAll sources urban to regional scale CAMx, CMAQ CAMx, CMAQ CAMx, CMAQSingle source long range transport assessments CALPUFF CALPUFFAll sources regional to continental scale CAMx, CMAQ CAMx, CMAQ CAMx, CMAQ


Focus AreasFocus Areas

• How well do we represent plume placement andHow well do we represent plume placement and chemistry near the source and far downwind?

• Single source modeling of long range transportOzone PM2 5 deposition at Class I areas for PSD and– Ozone, PM2.5, deposition at Class I areas for PSD and NSR programs

• Single source modeling on urban scaleSingle source modeling on urban scale– Ozone and PM2.5 (maybe visibility in the future) impact assessments for PSD and NSR programsp p g


Single Source – Long Range TransportSingle Source Long Range Transport

• Long range transport of ozone and PM2.5 (air quality or AQ) and deposition (air quality related values or AQRVs) to Class I areas for PSD/NSR assessments

• Looking at existing and alternative modeling systems for longLooking at existing and alternative modeling systems for long range transport assessments of PM2.5, AQRVs, and ozone– Currently working with other Federal Agencies (USFS), contractors

(ENVIRON/UNC) and internally to evaluate and compare modeling ( / ) y p gsystems

• Mesoscale Model InferFace tool developed to convert WRF or MM5 output directly to CALPUFF, SCICHEM/SCIPUFF, andMM5 output directly to CALPUFF, SCICHEM/SCIPUFF, and AERMOD– beta release of the MMIF tool in February 2012 (EPA SCRAM site)– AQMG team actively supporting the MMIF tool along with ENVIRONAQMG team actively supporting the MMIF tool along with ENVIRON


Consequence AnalysisConsequence Analysis

• Draft report “Comparison of Single‐Source Air Quality Assessment Techniques for Ozone, PM2.5, other Criteria Pollutants and AQRVs”– will be available on the EPA SCRAM site when complete

• Compares modeled estimates of air quality (PM2 5) and air‐qualityCompares modeled estimates of air quality (PM2.5) and air quality related values (deposition) of various LRT modeling systems at Class I area receptors in the western U.S.

I l d th li ti f CAM th l t i f• Includes the application of CAMx, the regulatory version of CALPUFF using CALMET and MMIF, and the most recent version of CALPUFF that includes additional PM chemistry options

• Discussed in more detail in Bret Anderson’s Wednesday presentation


Inert Tracer Experiment EvaluationInert Tracer Experiment Evaluation

• Draft final report “Documentation of CALPUFF and Other Long p gRange Transport Models using Tracer Test Experiment Data”– http://www.epa.gov/ttn/scram/reports/EPA‐454_R‐12‐003.pdf

R t d t il th l ti f lti l LRT di i• Report details the evaluation of multiple LRT dispersion modeling systems using multiple tracer field studies: CALPUFF, SCIPUFF, HYSPLIT, FLEXPART, CAMx, and CALGRID

• Examines sensitivity of CALPUFF to variations in CALMET application and MMIF tool

S i i i i f HYSPLIT CALPUFF d CAM l i• Sensitivities of HYSPLIT, CALPUFF, and CAMx to alternative configuration options

• Work done by US EPA/USFS; ENVIRON performed QA ofWork done by US EPA/USFS; ENVIRON performed QA of results and generated the report


Regional Inert Tracer Field ExperimentsRegional Inert Tracer Field Experiments

• Inert tracer release experiments provide a useful independent evaluation of long range transport and dispersion algorithms– A known amount of tracer gas is released– Release characteristics are typically well known– Measured at downwind receptor sites

• Several used by US EPA for 1998 evaluation study of y yCALPUFF v5.8– Savannah River Laboratory 1975 (SRL75)– Great Plaines 1980 (GP80)( )

• 1983 Cross‐Appalachia Tracer Experiment (CAPTEX) used extensively to test MM5 and WRF FDDA

• 1994 European Tracer Experiment (ETEX)1994 European Tracer Experiment (ETEX)


Comparisons to 1998 CALPUFF EvaluationComparisons to 1998 CALPUFF Evaluation

Great Plains 1980 (GP80) Tracer Field Experiment• CALPUFF “SLUG” near‐field option needed to reproduce

“good” model performance on 600 km arc from 1998 EPA study

• Using different valid CALMET configurations, the maximum CALPUFF estimated tracer concentrations vary by a factor of 3

• Less variation in CALPUFF tracer estimates using MMIF, but there are few options with MMIF

Savannah River Lab (SRL75) Tracer Field Experiment• Fitted Gaussian plume evaluation approach can be flawed

4/27/2012 All material shown is preliminary 9

CAPTEX 1983•2 of the 5 tracer releases from CAPTEX‐83 are used to evaluate LRT models•LRT models evaluated include CALPUFF, SCICHEM, HYSPLIT, FLEXPART, and CAMx

CAPTEX 1983

•All models applied using the same underlying 36 km MM5 output


CAPTEX 1983CAPTEX 1983

• CALPUFF sensitivities using CTEX3CALMET show CALMET

approach that most closest matches observations

CTEX3

provides comparatively (among CALPUFF/CALMET sens.) worst agreement ) gwith tracer observations

• Using 36 km prognostic data only composite

CTEX5

only, composite performance metrics shown for both releases at right for multiple LRT modelsmultiple LRT models

*Figures courtesy of ENVIRON


ETEX 1994ETEX 1994

• 1994 European Tracer Experiment– Two releases from NW France

in Oct. and Nov. 1994 2.0

2.4

Rank (RANK) (Perfect = 4)

– Tracer measured at 168 monitor sites

• LRT models evaluated 0 4

0.8

1.2

1.6

(1‐KS/100)

FMS/100

(1‐FB/2)

include CALPUFF, SCICHEM, HYSPLIT, FLEXPART, and CAMx

0.0

0.4

ALPUFF

CIPUFF

YSPLIT

XPA

RT

CAMx

( / )

R^2

• All models applied using the same underlying 36 km MM5 output

CA SC HY

FLE

*Figure courtesy of ENVIRON

MM5 output


ETEX 1994Observations (+36 hours) SCIPUFF CAMx

ETEX 1994

b ( h )Observations (+60 hours) SCIPUFF CAMx

*Figures courtesy of ENVIRON


Great Plains 1980Great Plains 1980

• Maximum field fmeasurements of tracers

shown at right for all monitors in the studyU d t l t CAM• Used to evaluate CAMxsensitivities to various Kzschemes and horizontal advection algorithms (BOTTadvection algorithms (BOTT and PPM) in LRT report

• Currently building on that work by evaluating variety ofwork by evaluating variety of horizontal and vertical advection approaches in CAMx (96 unique variations)


Great Plaines 1980Great Plaines 1980•CAMx using YSU Kz values (left) does well at capturing plume placement•Kz values using OB70 approach (right) advect mass too far to the SE at 600 km arcKz values using OB70 approach (right) advect mass too far to the SE at 600 km arc•Performance of tracer suggest underlying WRF wind fields are well characterized


Single Source – Urban scaleSingle Source Urban scale

• Need near field plume chemistry to estimate single source p y gimpacts on ozone and secondarily formed PM2.5 for PSD & NSR programs

Currently AERMOD is used to assess impacts of directly emitted PM2 5– Currently AERMOD is used to assess impacts of directly emitted PM2.5

• EPA granted Sierra Club petition with commitment to update Appendix W to address O3 and secondary PM2.5 impacts

• Need for technical basis to establish interpollutant trading ratios for PM2.5 to inform NSR offsets and SIP measures

D l d li id f i i l• Develop modeling guidance for assessing single source impacts on secondary pollutants such as ozone and PM2.5 relevant for PSD/NSR


Single Source – Urban scaleSingle Source Urban scale

• NACAA recommendation of a multi‐tier approach to assessing pp gsingle source impacts of PM2.5 (did not address ozone) that ranges from simple (screening level) to complex1) Use AERMOD for primary PM2 5 with offset ratios to approximate1) Use AERMOD for primary PM2.5 with offset ratios to approximate

secondary PM2.5; location specific offset ratios difficult to estimate

2) Use a Lagrangian model with plume chemistry (e.g. CALPUFF, SCICHEM)SCICHEM)

3) Use a photochemical modeling system (e.g. CAMx, CMAQ)• Source sensitivity, source apportionment, sub‐grid plume treatment?

d d d h h d ff h• U.S. EPA needs to understand how these different approaches are comparable and how best to apply models for this purpose to develop guidance and review future permits p p p g p


Single Source Screening Level ToolSingle Source Screening Level Tool

Are screening level tools for single source estimates of g gsecondary PM2.5 and ozone feasible?

• A screening tool would ideally provide a quick, reasonable, credible, and appropriately conservative assessment of single source secondary impactsappropriately conservative assessment of single source secondary impacts before more complex applications are required

• ENVIRON presented a reduced form single source screening model that estimates ozone impacts from single source emissions of VOC and/or NOXestimates ozone impacts from single source emissions of VOC and/or NOX based on CAMx‐HDDM

– http://www.epa.gov/ttn/scram/10thmodconf/presentations/2‐21‐Morris_Ozone_Screen_New_Srcs_EPA_10th_AQMC_Mar_2012.pdf

• AQMG plans to explore this approach for ozone and PM2.5 to support single source NSR/PSD screening assessments

• This modeling may provide some information for developing appropriate g y p p g pp pinterpollutant trading ratios for PM2.5


Plume Chemistry & PlacementPlume Chemistry & Placement

What are the best approaches when screening level assessments are not enough?

• Draft report “Evaluation of Chemical Dispersion Models using Atmospheric Plume Measurements from Field Experiments”p p– Will be available on the EPA SCRAM site when complete

• Compares modeled estimates of air quality (ozone) and key precursors of various LRT modeling systems using two plume p g y g pmeasurement field experiments: 1999 TVA and 2006 Oklaunion

• Includes the application of CAMx, SCICHEM, the regulatory version of CALPUFF using CALMET and MMIF, and the most recent version g ,of CALPUFF that includes additional PM chemistry options

• Additional detail on EPA’s SCICHEM application discussed in more detail in Jim Kelly’s presentation on Wednesdayy p y


Plume Chemistry & PlacementPlume Chemistry & Placement

• Application of photochemical modeling systems pp p g yfor single source O3 and PM2.5 assessments using a plume measurement field study (1999 TVA helicopter observations)TVA helicopter observations)

• Source sensitivity: CMAQ and CAMx brute force and DDM emissions sensitivity

• Source contribution: CMAQ and CAMx source apportionmentCAM fl i i & b id l• CAMx flexi‐nesting & sub‐grid plume treatment

• When available, CMAQ sub‐grid plume treatment (APT approach developed by EPRI)(APT approach developed by EPRI)


Modeling SetupModeling Setup

• 1999 hour specific CEM i i f TVA C b l demissions for TVA Cumberland

– http://camddataandmaps.epa.gov/gdm/index.cfm?fuseaction=emissions.wizard

• 1999 hour specific biogenicsti t d ith BEIS d lestimated with BEIS model

• 2001 NEI based anthropogenic emissions

• Meteorological inputs• Meteorological inputs generated using the WRF model version 3.3

• Photochemical models used: CMAQ v.4.7.1 and CAMx v5.40

• Domains (34 layers): 36 km CONUS 12 and 4 km


2 week (July 1999) episode maximum impact on NOX (NO+NO2) from source NOX

*red dot indicates source location


2 week (July 1999) episode maximum impact on ozone from source NOX

Ozone tracking has not beennot been

implemented yet in CMAQ



2 week (July 1999) episode maximum impact on elemental carbon from source EC


Current version of

lCAMx only includes DDM

for gases


g

2 week (July 1999) episode maximum impact on PM2.5 sulfate from source SOX


Current version of

lCAMx only includes DDM

for gases


g

Source – Receptor Proximity IssuesSource Receptor Proximity Issues• Source‐receptor spatial relationships are sometimes not resolved at 1 km

– In Figure below (from Illinois EPA), the source is outlined in green and the receptor isIn Figure below (from Illinois EPA), the source is outlined in green and the receptor is labeled ‘A’ (the meteorological station is labeled ‘B’)


Sub‐grid Plume TreatmentSub grid Plume Treatment

• What types of situations require the use of sub‐grid plume treatment? – Source‐receptor proximity may be such that they are in the same grid cell or only a single grid cell apartg y g g p

– How to configure plume‐in‐grid for PSD/NSR types of applications?

– What is the best way to track source contribution and/or y /sensitivity when combining sub‐grid and grid‐resolved techniques?

• When would the use of sub‐grid plume treatment beWhen would the use of sub grid plume treatment be inappropriate?

• What grid resolution (horizontal and vertical) could preclude the need for sub grid plume treatment?preclude the need for sub‐grid plume treatment?


Source – Receptor Proximity IssuesSource Receptor Proximity Issues

• Plume measurement 200 M 1 km w/ PiG

studies provide one opportunity to evaluate the utility of sub‐grid

/

the utility of sub grid plume treatments for PSD/NSR

d l d b• Modeling system and sub‐grid plume evaluation work is critical to develop pand improve modeling guidance for these situations 200 M 1 km w/ PiGsituations

4/27/2012 28*Graphics from Illinois EPA

All material shown is preliminary

Last SlideLast Slide

• OAQPS interested in input and participation from State and Local Agencies as we move forward to better understand single source modeling for secondary pollutants (O3 and PM2.5)p ( )

• Also looking for contributions from US EPA Regional offices and other government agencies

• Special session at this year’s CMAS meeting in Chapel• Special session at this year s CMAS meeting in Chapel Hill (October 2012) on modeling secondary impacts from single sources (www.cmascenter.org)A k l d h ib i f B A d Ji• Acknowledge the contributions of Bret Anderson, Jim Kelly, Tyler Fox, ENVIRON, CSC, OAQPS/AQAD emissions and modeling groups


estimating secondary pollutant impacts from single sources · estimating secondary pollutant...

Documents