1 Emissions Inventory Overview–Part 1 Melinda Ronca-Battista, ITEP

2 Overview What is an Emissions Inventory and why do we need one? Part 1 ◦ Types of EIs ◦ Pollutants ◦ Sources Part 2 ◦ Quantifying emissions ◦ Types of data collected ◦ Reporting

3 What is an Emissions Inventory? Listing of sources of estimated air pollutant emissions in geographic area during specific time period

4 What are Emission Sources? Point Sources On-Road Mobile Sources Non-Road Mobile Sources Non-Point Sources (Area Sources) Based on EPA

5 How are EI data used? Air quality management tool ◦ Collect baseline data ◦ Develop & track emissions control and management strategies Regulations development Air quality modeling and assessment Permits ◦ Do you have facilities that need permits? ◦ Conditions (potential to emit) ◦ Fees Emissions trading Regulatory compliance

6 Inventory Steps Source identification ◦ Phonebook/windshield survey ◦ NEI data, previous EIs Planning! ◦ Inventory Preparation Plan (IPP) ◦ Quality Assurance Project Plan (QAPP) Collect data ◦ From sources, permits, questionnaires, etc.

7 Inventory Steps (cont.) Calculate and analyze data (TEISS, Excel, GIS, etc.) Report data and present results ◦ Internal: tribal council, community ◦ External: EPA project officer, National Emissions Inventory (NEI)

8 Level of Detail Simple summary: Small reservation, few on-reservation sources ◦ Compiled from existing data sources ◦ Includes only large sources Comprehensive accounting: Large reservation, many and/or large sources ◦ Large on-reservation sources–permitting ◦ “Problem” emissions (agricultural burning, small industries, road dust, traffic emissions)

9 What are Emissions? Criteria Pollutants ◦ Particle matter: PM 10 and PM 2.5 ◦ Nitrogen oxides: NO x ◦ Sulfur dioxide: SO 2 ◦ Carbon monoxide: CO ◦ Lead: Pb Ozone precursors ◦ Ammonia: NH 3 ◦ Volatile Organic Compounds: VOCs HAPs (Air Toxics) ◦ 187 toxic, carcinogenic compounds without regulated standards

10 Criteria Pollutants What about Ozone? ◦ Ozone is not emitted directly by sources ◦ EIs inventory ozone precursors  VOCs  NOx  Both react with sunlight to form ozone. ◦ NOx and VOCs get inventoried, but not ozone itself

11 HAPs (Air Toxics) 187 compounds listed in CAA including ◦ Mercury (power plants, coal-fired) ◦ Perchloroethylene (dry cleaning) ◦ Benzene (gasoline) ◦ Chloroform (chlorination plants, paper mills) ◦ Methyl Isocyanate (pesticide manufacturing)  Release at Bhopal, India, killed 4,000 people ◦ The list goes on….

12 Types of Sources Point sources = Stationary sources Area sources = Non-Point sources Mobile sources ◦ On-Road (cars, motorcycles, trucks, buses) ◦ Non-Road (trains, heavy equip.) Biogenic sources

13 What is a Point Source? Individual, stationary source releasing pollutants to atmosphere Quantities above emission threshold Emission thresholds vary according to type of pollutant and non-attainment area classification for criteria pollutants See Air Emission Reporting Requirement (AERR) for more detail

14 What is a Point Source? (cont.) AERR reporting thresholds are quite high. Compared to Potential to Emit. Many states have lower thresholds Consider using state thresholds to define your reservation’s point sources ◦ Makes EI compatible with others in your area ◦ Get a more detailed listing of sources  Example: Busy gas station can be point source under state thresholds, but not EPA’s

15 Example: Point Source Thresholds Pollutant EPA’s AERR Reporting Thresholds New Mexico Reporting Thresholds Lead (Pb) ≥5 ton per year (tpy) >1 ton per year (tpy) PM10≥100 tpy>10 tpy PM2.5≥100 tpy>10 tpy Nitrogen Oxides (NOx) ≥100 tpy>10 tpy Carbon Monoxide (CO) ≥1000 tpy>10 tpy Volatile Organic Compounds (VOC) ≥100 tpy>10 tpy

16 Point Source Characteristics Large, stationary sources ◦ Manufacturing or production plants ◦ Power plants, refineries ◦ Large, industrial facilities One point source facility can have emissions from ◦ Smoke stacks ◦ Units within directed to stacks ◦ Fugitive sources within plant

17 Point Sources (cont.)

18 Area (Non-Point) Sources Stationary sources that emit ◦ Less than point source threshold ◦ Smaller emitters, but numerous ◦ Often have fugitive (uncontrollable) emissions Tend to be sources like Gasoline stations Dry cleaners Auto body/paint shops Unpaved roads

19 Other Area Sources Wildfires and prescribed burning ◦ E.g., agricultural field burning ◦ Now inventoried as EVENTS Other area source examples ◦ Residential wood combustion ◦ Residential combustion of household waste (backyard burning) Wildfires and prescribed burning ◦ E.g., agricultural field burning ◦ Now inventoried as EVENTS Other area source examples ◦ Residential wood combustion ◦ Residential combustion of household waste (backyard burning)

20 On-Road Mobile Sources Vehicles found on roads and highways (e.g., cars, trucks, buses, motorcycles) ◦ 20 volatile organic compounds (VOCs) and metals quantified (Urban Air Toxics) ◦ Diesel particulate matter and diesel exhaust organic gases also quantified

21 Non-Road Mobile Sources Mobile sources not found on roads and highways (e.g., airplanes, trains, lawn mowers, construction vehicles, farm machinery) 2/4 stroke engines aircraft locomotives commercial marine vessels hobby engines

22 Non-Road Mobile Sources Note about aircraft ◦ ALL airports are now considered point sources in the NEI ◦ If you have airports on your reservation, check the most recent NEI data. Use it in your EI ◦ UNLESS you have more accurate data.

23 Biogenic Sources Naturally occurring emissions ◦ Vegetation: Trees, shrubs, grasses ◦ Microbial: Soil bacteria, termites EPA estimates these emissions on a county level for entire country… …so you don’t have to