Preliminary Mobile Source
Significance Test
Modeling Results
WRAP Regional Modeling Center (RMC)
University of California at Riverside, CE-CERT
ENVIRON International Corporation
Presented at:
WRAP Initiatives Oversight Committee (IOC) Meeting
October 9, 2002
Tempe Mission Palms Hotel, Arizona
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
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
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
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
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
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)
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
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
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
Summary of Anthropogenic Emissions
in 9 Grand Canyon (GC) States
(No Biogenic, Geogenic, Fire, or Wind Blown
Dust Emissions)
Source
Category
Area
Road Dust
Point
Mobile
Non-Road
Total
NOX
(tpy)
(%)
377833 16%
0 0%
885720 37%
407691 17%
700271 30%
2371515 100%
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
SO2
NH3
(tpy)
(%)
(tpy)
(%)
74697
8% 594764 87%
0
0%
0 0%
642133
72% 30218 4%
5426
1% 57326 8%
175343
20%
3398 0%
897599 100% 685706 100%
PM10
(tpy)
(%)
1051116
61%
344659
20%
232786
13%
31557
2%
66232
4%
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
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
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
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
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%
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
Cumulative Mobile Source Significance Test
16 Class I Areas on CO Plateau
Arches NP
Black Canyon of Gunnison NP
Bryce Canyon NP
Canyonlands NP
Capitol Reef NP
Flat Tops Wilderness
Grand Canyon NP
Maroon Bells-Snowmass Wilderness
Mesa Verde NP
Mount Baldy Wilderness
Petrified Forest NP
San Pedro Parks Wilderness
Sycamore Canyon Wilderness
West Elk Wilderness
Weminuche Wilderness
Zion NP
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
% 9 GC States
18.81%
14.70%
15.97%
16.49%
20.48%
13.57%
18.31%
14.34%
8.27%
11.49%
14.28%
6.22%
19.14%
13.22%
10.84%
23.71%
Preliminary Individual Area Mobile Significance Test
Class I Areas
on the CO Plateau
Arches NP
Black Canyon Gunnison NP
Bryce Canyon NP
Canyonlands NP
Capitol Reef NP
Flat Tops Wilderness
Grand Canyon NP
Maroon Bells-Snowmass WA
Mesa Verde NP
Mount Baldy Wilderness
Petrified Forest NP
San Pedro Parks Wilderness
Sycamore Canyon Wilderness
West Elk Wilderness
Weminuche Wilderness
Zion NP
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
% 2018 No Mobile over natural background
9 GC States
California
Phoenix
Las Vegas
18.81%
0.43%
0.17%
14.70%
0.33%
0.31%
15.97%
5.31%
0.16%
16.49%
0.74%
0.27%
20.48%
4.09%
0.14%
13.57%
0.76%
-0.04%
18.31%
10.50%
0.97%
14.34%
-0.04%
0.06%
8.27%
0.92%
0.74%
11.49%
0.57%
2.98%
14.28%
0.94%
3.78%
6.22%
0.75%
0.64%
19.14%
7.96%
2.82%
13.22%
0.28%
0.24%
10.84%
-0.16%
0.48%
23.71%
5.77%
0.13%
Details Mobile Source Significance Test
9 GC States and Phoenix
Class I Area
Arches NP
Black Canyon NP
Bryce Canyon NP
Canyonlands NP
Capitol Reef NP
Flat Tops WA
Grand Canyon NP
Maroon Bells WA
Mesa Verde NP
Mount Baldy WA
Petrified Forest NP
San Pedro Parks
Sycamore Canyon
West Elk WA
Weminuche WA
Zion NP
Extinction Bext (Mm-1)
Bext (Mm-1)
No
No MS
Nat
No
Base No MS
9 GC S Phoenix Bckgnd 9 GC S Phoenix
0.03
3.78
35.86 20.12
32.11
35.90
0.06
2.98
31.44 20.26
28.53
31.51
0.03
3.21
33.85 20.12
30.67
33.88
0.06
3.31
34.00 20.08
30.74
34.06
0.03
4.13
35.51 20.18
31.40
35.53
-0.01
2.75
29.76 20.28
27.00
29.75
0.19
3.68
32.32 20.08
28.84
32.52
0.01
2.91
30.27 20.30
27.37
30.28
0.15
1.67
33.12 20.18
31.60
33.27
0.60
2.30
38.41 20.04
36.71
39.01
0.76
2.87
32.46 20.08
30.36
33.22
0.13
1.25
31.22 20.18
30.09
31.35
0.57
3.89
37.16 20.34
33.85
37.74
0.05
2.68
30.10 20.26
27.47
30.15
0.10
2.19
29.71 20.20
27.62
29.81
0.03
4.76
35.22 20.06
30.49
35.25
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
% Change Bext
No
No MS
9 GC S Phoenix
0.17%
18.81%
0.31%
14.70%
0.16%
15.97%
0.27%
16.49%
0.14%
20.48%
13.57% -0.04%
0.97%
18.31%
0.06%
14.34%
0.74%
8.27%
2.98%
11.49%
3.78%
14.28%
0.64%
6.22%
2.82%
19.14%
0.24%
13.22%
0.48%
10.84%
0.13%
23.71%
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
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
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%
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
Road Dust Emissions Significance Test
Using W20 Absolute Model Results (No RRFs)
16 Class I Areas
Colorado Plateau
Arches NP
Black Canyon of Gunnison NP
Bryce Canyon NP
Canyonlands NP
Capitol Reef NP
Flat Tops Wilderness
Grand Canyon NP
Maroon Bells-Snowmass WA
Mesa Verde NP
Mount Baldy Wilderness
Petrified Forest NP
San Pedro Parks Wilderness
Sycamore Canyon Wilderness
West Elk Wilderness
Weminuche Wilderness
Zion NP
Projects:/WRAP RMC/309_SIP/progress_sep02/Annex_MTF_Sep20.ppt
2018
2018
Natural Bext
Base No Road Bckgnd
No
-1
(Mm )
Dust
Worst Road
-1
(Mm )
Days
Dust
-1
(Mm ) (Mm-1)
25.91
25.63
20.12
0.29
32.84
32.20
20.26
0.63
24.24
23.99
20.12
0.25
23.89
23.71
20.08
0.18
25.56
25.30
20.18
0.26
28.55
28.37
20.28
0.19
27.78
27.53
20.08
0.25
31.78
31.46
20.30
0.32
34.47
34.21
20.18
0.26
41.63
41.26
20.04
0.37
32.46
32.22
20.08
0.24
28.90
28.65
20.18
0.24
35.34
34.95
20.34
0.39
31.15
30.85
20.26
0.30
29.93
29.77
20.20
0.16
25.57
24.95
20.06
0.61
Bext
No
Road
Dust
(%)
1.42
3.13
1.24
0.89
1.29
0.92
1.22
1.57
1.30
1.87
1.20
1.21
1.92
1.47
0.80
3.05
dv
No
Road
Dust
(dv)
0.14
0.31
0.12
0.09
0.13
0.09
0.12
0.16
0.13
0.19
0.12
0.12
0.19
0.15
0.08
0.30