Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt Preliminary Mobile Source Significance Test Modeling Results WRAP Regional Modeling Center

Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt

Preliminary Mobile Source Significance TestModeling Results

WRAP Regional Modeling Center (RMC)

University of California at Riverside, CE-CERT

ENVIRON International CorporationPresented at:

WRAP Initiatives Oversight Committee (IOC) Meeting

October 9, 2002

Tempe Mission Palms Hotel, Arizona


Section 309 SIP Modeling Elements

• Demonstrate that the SO2 Annex Milestone strategy is “better than” Command and Controls with Uncertainty in 2018

• Show visibility progress from 1996 to 2018• Evaluate the “significance” of mobile sources

and road dust on visibility– Topic of today’s presentation


Mobile Source Significance Test Metric(Draft Memo from Mobile Source Forum, 06/10/02)• Change in extinction due to Mobile Sources

over a clean natural background for Worst 20% Observed Visibility Days

• Applied for 16 Class I Areas on Colorado Plateau

• No On-Road and Non-Road Mobile Source Emissions (“Zero-Out”)– 9 Grand Canyon (GC) States– California– Phoenix MSA– Las Vegas MSA


Estimate 2018 Visibility using Model Scaling of 1996 Observations

• Scale observed 1996 concentrations using Relative Reduction Factors (RRFs)

• Separate for each Class I Area

• Separate for each species (SO4, NO3, OC, EC, Soil, and CM)

• Calculate based on the mean of the Worst 20% observed visibility days during 1996– e.g., SO42018 = SO4Obs_1996 x (SO4Model _2018/SO4Model_1996)


Mobile Source Significance Test -- Accounting for Missing Fugitive Dust Emissions

• No Wind Blown Dust in emissions inventory• Model results for Fine Soil and Coarse Matter

(CM) are missing major sources• Cannot use relative changes in modeling results

for Soil and CM• Set RRF(Soil) = RRF(CM) = 1.0

– i.e., 2018 CM&Soil = 1996 CM&Soil

• Not an issue for Mobile Source Significance Test as Mobile Source Soil and CM insignificant


Summary of Anthropogenic Emissionsin 9 Grand Canyon (GC) States

(No Biogenic, Geogenic, Fire, or Wind Blown Dust Emissions)

NOX SO2 NH3 PM10SourceCategory (tpy) (%) (tpy) (%) (tpy) (%) (tpy) (%)Area 377833 16% 74697 8% 594764 87% 1051116 61%Road Dust 0 0% 0 0% 0 0% 344659 20%Point 885720 37% 642133 72% 30218 4% 232786 13%Mobile 407691 17% 5426 1% 57326 8% 31557 2%Non-Road 700271 30% 175343 20% 3398 0% 66232 4% Total 2371515 100% 897599 100% 685706 100% 1726351 100%


Comments on Emissions in 9 GC States• 47% NOX due to Mobile Sources

– (64% Non-Road vs. 36% On-Road)

• 21% SO2 due to Mobile Sources

– Almost all (97%) due to Non-Road Sources– Non-Road gas engines use low sulfur gasoline– Non-Road Rules for some Non-Road equipment expected

before 2018 that would significantly reduce diesel sulfur content (~4000 ppm to 15 ppm)

• Mobile PM10 is 6% of total but consists of EC & OC with high light extinction efficiencies

• New soon to be released EPA NONROAD model results in substantial reductions in emissions


Preliminary Mobile Source Significance Calculation Caveats

• Still problems with SMOKE emissions processing, emission inputs for scattered days sometimes get corrupted– Screened out known bad days and get qualitatively same

result– Results consistent with previous No On-Road Mobile and

Bounding Mobile runs– Still problems with No Las Vegas Mobile runs so not

presented here

• Results are preliminary and the final numbers may change slightly, but basic results will remain unchanged


Mobile Source Draft Significance Thresholds (Draft Memo from Mobile Source Forum, 06/10/02)

• Draft Cumulative Approach due to Mobile Sources in 9 GC States– If < 10%, then individual area significant thresholds of

> 5% shall be used– If >= 10%, then individual area significant thresholds of

> 1% shall be used• Excludes area if it is in lowest 20% of contributions to

the cumulative impact

• Draft Individual Area Approach Significance– Approach#1: > 10%– Approach#2: > 1%


Cumulative Mobile Source Significance Test16 Class I Areas on CO Plateau % 9 GC StatesArches NP 18.81%Black Canyon of Gunnison NP 14.70%Bryce Canyon NP 15.97%Canyonlands NP 16.49%Capitol Reef NP 20.48%Flat Tops Wilderness 13.57%Grand Canyon NP 18.31%Maroon Bells-Snowmass Wilderness 14.34%Mesa Verde NP 8.27%Mount Baldy Wilderness 11.49%Petrified Forest NP 14.28%San Pedro Parks Wilderness 6.22%Sycamore Canyon Wilderness 19.14%West Elk Wilderness 13.22%Weminuche Wilderness 10.84%Zion NP 23.71%


Preliminary Individual Area Mobile Significance Test % 2018 No Mobile over natural backgroundClass I Areas

on the CO Plateau 9 GC States California Phoenix Las VegasArches NP 18.81% 0.43% 0.17%Black Canyon Gunnison NP 14.70% 0.33% 0.31%Bryce Canyon NP 15.97% 5.31% 0.16%Canyonlands NP 16.49% 0.74% 0.27%Capitol Reef NP 20.48% 4.09% 0.14%Flat Tops Wilderness 13.57% 0.76% -0.04%Grand Canyon NP 18.31% 10.50% 0.97%Maroon Bells-Snowmass WA 14.34% -0.04% 0.06%Mesa Verde NP 8.27% 0.92% 0.74%Mount Baldy Wilderness 11.49% 0.57% 2.98%Petrified Forest NP 14.28% 0.94% 3.78%San Pedro Parks Wilderness 6.22% 0.75% 0.64%Sycamore Canyon Wilderness 19.14% 7.96% 2.82%West Elk Wilderness 13.22% 0.28% 0.24%Weminuche Wilderness 10.84% -0.16% 0.48%Zion NP 23.71% 5.77% 0.13%


Details Mobile Source Significance Test9 GC States and Phoenix

Extinction Bext (Mm-1) Bext (Mm-1) % Change BextClass I AreaBase No MS

9 GC SNo

PhoenixNat

BckgndNo MS9 GC S

NoPhoenix

No MS9 GC S

NoPhoenix

Arches NP 35.90 32.11 35.86 20.12 3.78 0.03 18.81% 0.17%Black Canyon NP 31.51 28.53 31.44 20.26 2.98 0.06 14.70% 0.31%Bryce Canyon NP 33.88 30.67 33.85 20.12 3.21 0.03 15.97% 0.16%Canyonlands NP 34.06 30.74 34.00 20.08 3.31 0.06 16.49% 0.27%Capitol Reef NP 35.53 31.40 35.51 20.18 4.13 0.03 20.48% 0.14%Flat Tops WA 29.75 27.00 29.76 20.28 2.75 -0.01 13.57% -0.04%Grand Canyon NP 32.52 28.84 32.32 20.08 3.68 0.19 18.31% 0.97%Maroon Bells WA 30.28 27.37 30.27 20.30 2.91 0.01 14.34% 0.06%Mesa Verde NP 33.27 31.60 33.12 20.18 1.67 0.15 8.27% 0.74%Mount Baldy WA 39.01 36.71 38.41 20.04 2.30 0.60 11.49% 2.98%Petrified Forest NP 33.22 30.36 32.46 20.08 2.87 0.76 14.28% 3.78%San Pedro Parks 31.35 30.09 31.22 20.18 1.25 0.13 6.22% 0.64%Sycamore Canyon 37.74 33.85 37.16 20.34 3.89 0.57 19.14% 2.82%West Elk WA 30.15 27.47 30.10 20.26 2.68 0.05 13.22% 0.24%Weminuche WA 29.81 27.62 29.71 20.20 2.19 0.10 10.84% 0.48%Zion NP 35.25 30.49 35.22 20.06 4.76 0.03 23.71% 0.13%


Comments on Mobile Significance Calculations• Effects of High Sulfur Diesel in Non-Road

– If Non-Road SO2 emissions are reduced by 75%, MS significance reduced but still > 10%/1%

• Effects of New NONROAD Model– Substantially lower, no numbers available

• If Applied Sig Test to On-Road Mobile Only– Approximately a factor of 3 reduction– Expect Cumulative < 10%; Individual < 5%

• Use 2018 Background Visibility instead of 2064– Reduce impacts by 1/3 to 1/2


Road Dust Significance Results

• Road Dust mainly in Soil and CM components so cannot use scaled modeling results– Currently Road Dust is 20% of PM10 emissions in 9

GC States (w/o wind blown dust)

• Use Absolute Modeling Results• Results presented at Denver 06/10/02 WRAP

Workshop No Road Dust in the Entire Domain– Will be conservative (overestimate) of Road Dust

emission impacts for 9 GC States

• Cumulative impact from 0.80% to 3.13%


Road Dust Emissions Significance TestUsing W20 Absolute Model Results (No RRFs)

16 Class I AreasColorado Plateau

2018Base

(Mm-1)

2018No Road

Dust(Mm-1)

NaturalBckgndWorstDays

(Mm-1)

BextNo

RoadDust

(Mm-1)

BextNo

RoadDust(%)

dvNo

RoadDust(dv)

Arches NP 25.91 25.63 20.12 0.29 1.42 0.14Black Canyon of Gunnison NP 32.84 32.20 20.26 0.63 3.13 0.31Bryce Canyon NP 24.24 23.99 20.12 0.25 1.24 0.12Canyonlands NP 23.89 23.71 20.08 0.18 0.89 0.09Capitol Reef NP 25.56 25.30 20.18 0.26 1.29 0.13Flat Tops Wilderness 28.55 28.37 20.28 0.19 0.92 0.09Grand Canyon NP 27.78 27.53 20.08 0.25 1.22 0.12Maroon Bells-Snowmass WA 31.78 31.46 20.30 0.32 1.57 0.16Mesa Verde NP 34.47 34.21 20.18 0.26 1.30 0.13Mount Baldy Wilderness 41.63 41.26 20.04 0.37 1.87 0.19Petrified Forest NP 32.46 32.22 20.08 0.24 1.20 0.12San Pedro Parks Wilderness 28.90 28.65 20.18 0.24 1.21 0.12Sycamore Canyon Wilderness 35.34 34.95 20.34 0.39 1.92 0.19West Elk Wilderness 31.15 30.85 20.26 0.30 1.47 0.15Weminuche Wilderness 29.93 29.77 20.20 0.16 0.80 0.08Zion NP 25.57 24.95 20.06 0.61 3.05 0.30

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Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt Preliminary Mobile Source Significance Test Modeling Results WRAP Regional Modeling Center