2011 Emission Inventory

My Reservation

2011 Emission Inventory

January 2014

TABLE OF CONTENTS

Executive Summary

Introduction

Results

Introduction

Reservation Location

Emissions Area

Point Sources

Criteria Pollutant Emissions

Ammonia (NH3)

Carbon Monoxide (CO)

Oxides of Nitrogen (NOx)

Particulate Matter 10 micrometers in diameter or smaller, including filterables and condensibles (PM10-PRI)

Particulate Matter 2.5 micrometers in diameter or smaller, including filterables and condensibles (PM2.5-PRI)

Sulfur Dioxide (SO2)

Volatile Organic Compounds (VOC)

Lead (Pb)

Summary and Recommendations

Nonpoint Sources

Criteria Pollutant Emissions

Ammonia (NH3)

Carbon Monoxide (CO)

Oxides of Nitrogen (NOx)

Particulate Matter 10 micrometers in diameter or smaller, including filterables and condensibles (PM10-PRI)

Particulate Matter 2.5 micrometers in diameter or smaller, including filterables and condensibles (PM2.5-PRI)

Sulfur Dioxide (SO2)

Volatile Organic Compounds (VOC)

Lead (Pb)

Summary and Recommendations

Non-Road Mobile Sources

Criteria Pollutant Emissions

Ammonia (NH3)

Carbon Monoxide (CO)

Oxides of Nitrogen (NOx)

Particulate Matter 10 micrometers in diameter or smaller, including filterables and condensibles (PM10-PRI)

Particulate Matter 2.5 micrometers in diameter or smaller, including filterables and condensibles (PM2.5-PRI)

Sulfur Dioxide (SO2)

Volatile Organic Compounds (VOC)

Lead (Pb)

Summary and Recommendations

On-Road Mobile Sources

Criteria Pollutant Emissions

Summary and Recommendations

Executive Summary

Introduction

This 2011 emission inventory (EI) for My Reservation was developed to identify sources of air pollution that may affect the My Reservation air quality. This EI is a Level 4 EI and is composed entirely of emissions data already calculated and available from the EPA national database of reported emissions (NEI). This inventory used these available data, imported into software that allows mapping and reporting of sources, to analyze what information is already known about sources near and on the reservation. The tribe is using this analysis of existing data to determine what sources on the reservation to focus on when a Level 1, 2, or 3 EI is developed. (EIs of Levels 1, 2 or 3 are those in which source data are gathered by the tribe to use in calculations.) The source categories in this EI include point, nonpoint, non-road, and on-road. The EI is limited to these EPA criteria pollutants:

Ammonia (NH3)
Carbon Monoxide (CO)
Oxides of Nitrogen (NOx)
Particulate Matter ten micrometers in diameter or smaller (PM10)
Particulate Matter two and a half micrometers in diameter or smaller (PM2.5)
Sulfur Dioxide (SO2)
Volatile Organic Compounds (VOCs)
Lead (Pb).

Results

The tribe used a buffer of approximately 10 miles from the reservation boundaries to determine what point sources to include in the EI. Based upon our topography and information about our airshed, point sources more than 10 miles from the reservation boundary do not significantly affect the My Reservation air quality. For nonpoint, non-road, and on-road sources, CoconinoCounty, that surrounds the reservation, is considered the emissions area. Table 1 shows the total emissions in the area of interest, in tons, for each source type.

Table 1: Emissions (tons) in Area of Interest (see Module 5 for tips on modifying and exporting TEISS reports, the point data are transcribed from the “by Facility” TEISS report, the other data in this table are copied from the Nonpoint Source, Non-Road Source, and On-Road Sources “by Location Cross-Tab” reports in TEISS, saved as “MS Excel 97-2000 Data only”)

Source Type / CO / NH3 / NOX / PM10-PRI / PM25-PRI / SO2 / VOC / Lead
Point / 195 / 964 / 22 / 22 / 3 / 43 / 0.04
Nonpoint / 124,716 / 1,794 / 7,668 / 17,330 / 8,613 / 635 / 201,081 / 0.0135
Non-Road / 9,493 / 1 / 670 / 88 / 83 / 2 / 2,228
On-Road / 20,172 / 82 / 6,549 / 276 / 226 / 24 / 1,760
Total / 154,381 / 2,072 / 15,851 / 17,716 / 8,944 / 664 / 205,112 / 0.0535

As shown in Table 1, for pollutants other than lead, the nonpoint category accounts for the majority of the emissions.
For lead, the point category accounts for the majority of the emissions.
The tribe plans to focus primarily on selected nonpoint sources, identified by this EI, on the reservation when the Level 1, 2, or 3 EI is developed. The tribe plans on collecting activity data and using those data to estimate the emissions for these sources.
The tribe plans on including fewer non-road sources than nonpoint sources when the Level 1, 2, or 3 EI is developed. The tribe plans to calculate emissions as a portion of the existing CoconinoCounty emissions. The tribe plans to base this allocation on the ratio of reservation land area to CoconinoCounty land area.
Since there are not any major roads that traverse the reservation, the tribe does not plan on including any on-road sources on the reservation in the Level 1, 2, or 3 EI. The tribe does plan on estimating emissions from the roads near the reservation as a portion of existing emissions data, butas an off-reservation source.

Based on this EI and the concerns voiced by the community about PM, the tribe plans on instituting pollution controls for two nonpoint sources, unpaved roads and woodstoves, identified as areas of concern in this EI. The tribe plans on asking Tribal Council to approve a project that could pave 80% of unpaved roads on the reservation and therefore decrease some of the particulate matter emissions. In addition, the tribe plans to offer an incentive for residents to switch out their old woodstoves with new ones that have lower emissions. Since an inventory that shows the emissions directly from unpaved roads and woodstoves on the reservation might be necessary to secure the funds for these projects, it is of particular importance to estimate the reservation emissions from these sources in the Level 1, 2, or 3 EI.

There are not any point sources on the reservation that the tribe plans to inventory in the Level 1, 2, or 3 EI. This EI identified a facility approximately 4 miles from the reservation boundary that exceeds the EPA point source emissions threshold for NOx emissions. This is the closest facility to the reservation and the tribe should consider setting up a NOx air monitoring station on a section of the reservation that is nearest to the facility.

Introduction

This 2011 emission inventory (EI) for My Reservation was developed to identify sources of air pollution that may affect the My Reservation air quality. This EI is a Level 4 EI and is composed entirely of data already reported to the EPA’s National Emissions Inventory (NEI). These data include emissions estimates for nonpoint, non-road, and on-road sources that include portions of reservation land, because in most cases, county emissions estimates for these source types do not exclude the portions of the source (e.g., unpaved roads) on reservation land. Most point sources, excluding airports, that are on the reservation are not included in the NEI unless the tribe has reported them. This inventory is intended to provide critical information on what sources in our area emit what pollutants, and the relative magnitudes of these pollutants, as already calculated and in the NEI. This is a recommended first step toward understanding what is in our air and where it came from, and (depending on funding) preparing an EI that includes emissions calculated by the tribe with activity data the tribe gathers for specific sources on tribal land.

The source categories include point, nonpoint, non-road, and on-road. The EI is limited to these EPA criteria pollutants:

Ammonia (NH3)
Carbon Monoxide (CO)
Oxides of Nitrogen (NOx)
Particulate Matter ten micrometers in diameter or smaller (PM10)
Particulate Matter two and a half micrometers in diameter or smaller (PM2.5)
Sulfur Dioxide (SO2)
Volatile Organic Compounds (VOCs)
Lead (Pb).

This is the first EI that has been completed for My Reservation and the primary purpose is to review existing emissions data from the EPA National Emission Inventory (NEI) database. From this analysis of the existing data, the tribe can determine what sources on the reservation to focus on when a Level 1, 2, or 3 EI is developed. It can also be used to focus attention on what sources should be controlled to improve the My Reservation air quality and in the determination of locations for potential air monitoring stations.

Reservation Location

My Reservation is located in Coconino County in northern Arizona. My Reservation is 90 square miles with 120 living on the reservation in 2011. The location is primarily rural with the nearest major city of Flagstaff approximately 20 miles southeast. A smaller city of Williams is approximately 5 miles south.

Emissions Area

The 2011 NEI version 1.0 General Purpose Release (GPR) data for Coconino County were downloaded from the NEI as a zipped file, then converted to a format that is importable into the Tribal Emission Inventory Software Solution (TEISS) (see Module 4 for instructions on importing data). TEISS is an emission inventory development software that is available at no charge to federally recognized tribes through the Institute of Tribal Environmental Professionals (ITEP) at Northern Arizona University (NAU). TEISS has a geographic information system (GIS) interface allowing the data to be mapped. Figure 1 shows a map of My Reservation with the 10 mile buffer for point sources (Point Source Emissions Area). Figure 2 shows a zoomed in version of the map.

TEISS allows the user to select point sources and identify where they are and their estimated emissions, and view nonpoint emissions as reported for the surrounding county. In this way, we can evaluate what existing information there is on the relative importance of various types of sources and identify what point sources are most important for our air quality.

Figure 1: Reservation and Point Source Emissions Area, Zoomed Out (See Module 6 for tips on modifying and exporting maps. To draw the circular buffer zone, use the Circle Annotation tool in the Annotation toolbar. Add text to the circular buffer zone by using the Text Annotation tool in the Annotation toolbar. Measure the distance the buffer zone is from reservation boundaries with the Measure Distance and Area tool in the Annotation toolbar. This map was exported by going to the Export selection in the TEISS menu, then selecting Copy to File, and then selecting JPEG. )

Figure 2: Reservation and Point Source Emissions Area, Zoomed In (This map was exported by going to the File selection in the TEISS menu and then selecting Print. Make additions in the Print Preview box and change the Orientation from Portrait to Landscape , then click on the Save icon that looks like a floppy disk to export the map.)

Point Sources

There are five facilities that are within the 10 mile radius of the reservation boundaries, as shown by the maps in Figure 1 and Figure 2. The tribe used TEISS to identify these sources (zoom in on the map and click on the facilities to view their names) and measure the approximate distance from the reservation boundaries (measure distance of the facilities from reservation boundaries with the Measure Distance and Area tool in the Annotation toolbar). Table 2 lists these facilities, with the North American Industrial Classification System (NAICS) description (find the NAICS description in Input View of TEISS, select Facilities, click on Facility of interest, and then click Edit) and the approximate distance from the reservation boundaries.

Table 2: List of Facilities within Ten Mile Buffer Zone

Facility Name / NAICS Description / Approximate Distance from Reservation Boundary (miles)
EPNG-Williams Compressor Station / Pipeline Transportation of Natural Gas / 4
TW-Flagstaff Compressor Station / Pipeline Transportation of Natural Gas / 7
H.A. Clark Memorial Field / Airport Operations / 6
Sunrise Ranch / Airport Operations / 9
Valle / Airport Operations / 9

Criteria Pollutant Emissions (see Module 5 for tips on modifying and exporting TEISS reports, these figures and charts are screen captures from the “by Facility” TEISS report)

Ammonia (NH3)

Ammonia emissions were not reported to NEI for any of the five facilities in the Point Source Emissions Area.

Carbon Monoxide (CO)

Two of the five facilities in the Point Source Emissions Area accounted for 82% of the CO emissions. The EPNG-Williams Compressor Station was the largest source of CO, emitting 136 tons in 2011. This amount was 70% of all CO emitted by point sources in the Point Source Emissions Area. The H.A. Clark Memorial airport emitted 23 tons of CO in 2011, or 12% of CO emissions in the Point Source Emissions Area. CO emissions from these facilities are below the EPA point source reporting threshold of 1000 tons per year.

Figure 3: CO Emissions (tons) from Facilities in Point Source Emissions Area

Oxides of Nitrogen (NOx)

One of the five facilities in the Point Source Emissions Area accounted for 95% of the NOx emissions. The EPNG-Williams Compressor Station was the largest source of NOx, emitting 915 tons in 2011. NOx emissions from this facility are above the EPA point source reporting threshold of 100 tons per year.

Figure 4: NOx Emissions (tons) from Facilities in Point Source Emissions Area

Particulate Matter 10 micrometers in diameter or smaller, including filterables and condensibles (PM10-PRI)

Two of the five facilities in the Point Source Emissions Area accounted for 96% of the total PM10-PRI emissions. The EPNG-Williams Compressor Station was the largest source of PM10-PRI emitting 15 tons in 2011. This amount was 70% of all PM10-PRI emitted by point sources in the Point Source Emissions Area. The TW-Flagstaff Compressor Station facility emitted 6 tons of PM10-PRI in 2011, or 26% of PM10-PRI in the Point Source Emissions Area. PM10-PRI emissions from these facilities are below the EPA point source reporting threshold of 100 tons per year.

Figure 5: PM10-PRI Emissions (tons) from Facilities in Point Source Emissions Area

Particulate Matter 2.5 micrometers in diameter or smaller, including filterables and condensibles (PM2.5-PRI)

Two of the five facilities in the Point Source Emissions Area accounted for 96% of the total PM2.5-PRI emissions. The EPNG-Williams Compressor Station was the largest source of PM2.5-PRI emitting 15 tons in 2011. This amount was 70% of all PM2.5-PRI emitted by point sources in the Point Source Emissions Area. The TW-Flagstaff Compressor Station facility emitted 6 tons of PM2.5-PRI in 2011, or 26% of PM2.5-PRI in the Point Source Emissions Area. PM2.5-PRI emissions from these facilities are below the EPA point source reporting threshold of 100 tons per year.

Figure 6: PM2.5-PRI Emissions (tons) from Facilities in Point Source Emissions Area

Sulfur Dioxide (SO2)

One of the five facilities in the Point Source Emissions Area accounted for 82% of the total SO2 emissions. The TW-Flagstaff Compressor Station was the largest source of SO2 emitting 2 tons in 2011. The SO2 emissions from this facility are below the EPA point source reporting threshold of 100 tons per year. The other facilities in the Point Source Emissions Area emitted less than 1 ton of SO2 in 2011.

Figure 7: SO2 Emissions (tons) from Facilities in Point Source Emissions Area

Volatile Organic Compounds (VOC)

Two of the five facilities in the Point Source Emissions Area accounted for 97% of the total VOC emissions. The EPNG-Williams Compressor Station was the largest source of VOC emitting 38 tons in 2011. This amount was 87% of all VOC emitted by point sources in the Point Source Emissions Area. The TW-Flagstaff Compressor Station facility emitted 4 tons of VOC in 2011, or 10% of VOC in the Point Source Emissions Area. VOC emissions from these facilities are below the EPA point source reporting threshold of 100 tons per year.

Figure 8: VOC Emissions (tons) from Facilities in Point Source Emissions Area

Lead (Pb)

The three airport facilities are the only facilities in the Point Source Emissions Area that have reported Pb emissions. The H.A. Clark Memorial airport and the Valle airport emitted 0.02 tons each of Pb in 2011. The Sunrise Ranch airport emitted less than 0.01 tons of Pb in 2011. Pb emissions from these facilities are below the EPA point source reporting threshold of 0.5 tons per year.

Figure 9: Pb Emissions (tons) from Facilities in Point Source Emissions Area

Summary and Recommendations - Point Sources

With the exception of SO2 and Pb, the EPNG-Williams Compressor Facility Station was the largest emitter in 2011. However, it only exceeded the EPA point source emissions threshold for NOx emissions. Since this is the closest facility to the reservation at approximately 4 miles from reservation boundaries, the tribe should consider setting up a NOx air monitoring station on a section of the reservation that is nearest to the facility. There are not any point sources on the reservation that the tribe plans on inventorying when the Level 1, 2, or 3 EI is developed.

Nonpoint Sources

To identify sources of concern, the tribe used TEISS to produce a report that shows the top 10 nonpoint emission sources in Coconino County for each pollutant of interest.

Criteria Pollutant Emissions (see Module 5 for tips on modifying and exporting TEISS reports, these figures are screen captures from the Nonpoint Sources “by SCC Top 10” TEISS report with an SCC level of 7 specified)

Ammonia (NH3)

Two sources in Coconino County accounted for 77% of the total NH3 emissions from nonpoint sources. Prescribed burning of forests was the largest source of NH3 emitting 782 tons in 2011, or 44% of NH3 emitted by nonpoint sources. Forest wildfires emitted 588 tons of NH3 in 2011, or 33% of NH3 emitted by nonpoint sources. Additionally, livestock sources emit significant amounts of NH3 and are considered sources of concern in this area.