1. WRAP Technical Planning Meeting Salt Lake City, UT December 5, 2018
Task 2: Emissions Inventory Development Issues Encountered During 2014 Inventory Development Emissions Inventory & Modeling Protocol Subcommittee
WRAP Technical Planning Meeting
Salt Lake City, UT
December 5, 2018

2. Emissions Inventory Review Checklist
Point
Oil & Gas
EGU
Other Point (non-IPM)
Minors / Non-Majors
Non-Point
Area Fugitive Dust
Agricultural Livestock Waste and Fertilizer Application
Agricultural Burning
CMV Onshore and Offshore
Rail
Residential Wood Combustion
All Other
On-Road Mobile
Activity data (VMT, VPOP, SPEED)
Non-Road Mobile
Biogenic
Land Use
Emission Factors
Modeling Methodology
NEI: BEIS; Modelers: MEGAN
Fire Events
Wildfire
Prescribed Burning
Reviewed
Not Reviewed by EI Subcommittee

3. Emissions Inventory Review Checklist (cont.)
Ancillary / Support Modeling Files
Temporal Profiles (and Holidays file)
Chemical Speciation (CB05 or CB06)
Spatial Surrogates
Stack Parameter Lookups
Reference Counties (for On-Road MOVES)
Area to Point (e.g. Airport Operations)
Other Review Notes
Pollutants
CAPs
NOx, SO2, PM10, PM2.5, NH3,
VOCs, CO,
HAPs / Toxics
Reviewed
Not Reviewed by EI Subcommittee

4. Base Year Selection 2014 NEI v2 Complete with State Input
2016 Modeling Platform
Still in development
Relies on Growth Factors for nonpoint
Little State Input

5. Methodology Differences Across Borders
EPA estimates all emissions categories using one methodology (~ NEI v1)
States provide emissions estimates based on better local knowledge or more refined method (~ NEI v2)
Potentially different model or calculation method
Could use different emission factors, assumptions, activity data, or granular detail (e.g. county vs state-wide factors)
Large Differences:
Unpaved Road Dust
On-Road
California wholesale replacement
Fire

6. Methodology Differences Across Borders (cont.)
MOVES input data submitted (dark)

7. Methodology Differences Across Borders (cont.)
Percentage of Emissions in 2014 NEIv2 that was submitted by State or Local agency
Point Sources
Nonpoint Sources
NH3
NOX
PM10
PM2.5
SO2
Alaska 99 94 89 25 92 9 4
Arizona 84 90 77 59 97 2 16 1 7 37
Maricopa County 15 83 53
CARB 72 86 85 51 76 55 70
Colorado 95 98 66 3
Hawaii
100 87 91
Idaho 29 33 75 34 49 57 65
Montana
Nevada
Clark County 73 5 43 78
Washoe County 18 12 17
New Mexico
City of Albuquerque 74 54 35 79 27 82
North Dakota
Oregon 30 11 60
South Dakota 64
Utah 96 26 22 19
Washington 88 93
Wyoming

8. Other Complications Different Reporting Thresholds for Point Sources
States may include some, all, or no minor sources
Missing Stack Parameters for Point Sources
Point Source Representativeness
5-yr average?
New Sources
Typical Year of Facility Activity?
Potential problems with EPA MOVES input data (e.g. fleet age distribution)
“Sector Summaries” from EPA not based on NAICS code
A point source may be broken into multiple “sectors”
Augmenting / Regenerating model-ready files
State
Minors Submitted to EPA?
Alaska
Yes (see updates on wiki)
Arizona
Pima County says No – AZDEQ: No
California
Yes - All minors submitted for NEI years
Colorado
Yes - All sources down to 1 ton
Hawaii No
Idaho
Montana
Yes – Sources down to 25 tons except portables
Nevada
New Mexico
North Dakota
Oregon
South Dakota
Utah
Washington
Wyoming

9. Complications for Future Year Modeling
How to represent fire events for future years?
Point source growth factors to be applied to “representative” year?
What else do we want on this list?
International Emissions – Do we use EPRI’s numbers?