HomeMy WebLinkAboutState of Air Quality Report 022018State of Air Quality
Surrounding the
Northampton Compressor Station,
Atlantic Coast Pipeline
North Carolina Department of Environmental Quality
Division of Air Quality
Planning Section
February 20, 2018
PREFACE
This document contains the Division of Air Quality’s (DAQ) review of the state of air quality,
the sources of air pollution, and other relevant information surrounding the Northampton
Compressor Station. We are providing this information to help the reader better understand the
type and quantity of air emissions releases, the overall state of air quality and other demographic
and environmental statistics as reported or compiled by the DAQ, the Environmental Protection
Agency, and other local, state and federal groups. For the purpose of presenting these data, the
area of interest is defined as Northampton County and Halifax County in North Carolina and
portions of Brunswick County, Greensville County and Southampton County in Virginia.
Table of Contents
Air Quality Monitoring Data ........................................................................................... 1
1.1 Satellite Imagery Data ...................................................................................................... 4
Air Emissions Source Categorization .............................................................................. 6
2.1 Nitrogen Oxide (NOx) Emissions .................................................................................... 7
2.2 Fine Particulate Matter (PM2.5) Emissions ....................................................................... 8
2.3 Sulfur Dioxide (SO2) Emissions ...................................................................................... 9
2.4 Carbon Monoxide (CO) Emissions ................................................................................ 10
2.5 Volatile Organic Compounds (VOC) Emissions ........................................................... 11
2.6 Ammonia Emissions ...................................................................................................... 12
2.7 Federal Hazardous Air Pollutants (HAPs) ..................................................................... 13
2.8 State Toxic Air Pollutants .............................................................................................. 16
2.9 North Carolina and Virginia Power Plant Emissions Data ............................................ 19
2.10 Prescribed Fires and Wildfire Events ............................................................................. 25
2.11 Greenhouse Gas Emissions ............................................................................................ 32
Wind Rose ...................................................................................................................... 35
Demographic and Socioeconomic Data ......................................................................... 37
4.1 CDC Statistics for Halifax County ................................................................................. 38
4.2 CDC Statistics for Northampton County ....................................................................... 41
EJSCREEN .................................................................................................................... 44
5.1 Northampton County EJSCREEN Report (Version 2017) ............................................ 46
5.2 Halifax County EJSCREEN Report (Version 2017)...................................................... 49
National Air Toxics Assessment (NATA) ..................................................................... 52
6.1 National Air Toxics Assessment (NATA) for Halifax and Northampton County
(Source: EPA Draft) ...................................................................................................... 54
Table of Figures
Figure 2.1 Northampton Compressor Station Area – NOx Emitting Facilities .............................. 7
Figure 2.2 Northampton Compressor Station Area – PM2.5 Emitting Facilities ........................... 8
Figure 2.3 Northampton Compressor Station Area – SO2 Emitting Facilities............................... 9
Figure 2.4 Northampton Compressor Station Area – CO Emitting Facilities .............................. 10
Figure 2.5 Northampton Compressor Station Area – VOC Emitting Facilities ........................... 11
Figure 2.6 Statewide Toxic Pollutant Totals Trend (1993-2015) ................................................. 17
Figure 2.7 Halifax and Northampton Counties Toxic Pollutants Totals Trends (1993-2015) ..... 17
Figure 2.8 Toxic Pollutants Trends by County (1993-2015) ........................................................ 18
Figure 2.9 Westmoreland Partners Roanoke Valley I Facility Level 2014 Daily SO2 Emissions
(tons) ............................................................................................................................................. 20
Figure 2.10 Westmoreland Partners Roanoke Valley I Facility Level 2014 Daily NOx Emissions
(tons) ............................................................................................................................................. 20
Figure 2.11 Westmoreland Partners Roanoke Valley I Facility Level 2014 Daily CO2 Emissions
(tons) ............................................................................................................................................. 20
Figure 2.12 Westmoreland Partners Roanoke Valley II Facility Level 2014 Daily SO2 Emissions
(tons) ............................................................................................................................................. 21
Figure 2.13 Westmoreland Partners Roanoke Valley II Facility Level 2014 Daily NOx Emissions
(tons) ............................................................................................................................................. 21
Figure 2.14 Westmoreland Partners Roanoke Valley II Facility Level 2014 Daily CO2 Emissions
(tons) ............................................................................................................................................. 21
Figure 2.15 Rosemary Power Station Facility Level 2014 Daily SO2 Emissions (tons) .............. 22
Figure 2.16 Rosemary Power Station Facility Level 2014 Daily NOx Emissions (tons)............. 22
Figure 2.17 Rosemary Power Station Facility Level 2014 Daily CO2 Emissions (tons) ............. 22
Figure 2.18 Southampton Power Station Facility Level 2014 Daily SO2 Emissions (tons) ......... 23
Figure 2.19 Southampton Power Station Facility Level 2014 Daily NOx Emissions (tons) ....... 23
Figure 2.20 Southampton Power Station Facility Level 2014 Daily CO2 Emissions (tons) ........ 23
Figure 2.21 Brunswick Power Station Facility Level 2014 Daily SO2 Emissions (tons) ............. 24
Figure 2.22 Brunswick Power Station Facility Level 2014 Daily NOx Emissions (tons) ........... 24
Figure 2.23 Brunswick Power Station Facility Level 2014 Daily CO2 Emissions (tons) ............ 24
Figure 2.24 Northampton Compressor Station Area - 2014 Prescribed Fire Locations ............... 26
Figure 2.25 Northampton Compressor Station Area - 2014 Wildfire Locations .......................... 27
Figure 2.26 Northampton Compressor Station Area - 2015 Prescribed Fire Locations ............... 28
Figure 2.27 Northampton Compressor Station Area - 2015 Wildfire Locations .......................... 29
Figure 2.28 Northampton Compressor Station Area - 2016 Prescribed Fire Locations ............... 30
Figure 2.29 Northampton Compressor Station Area - 2016 Wildfire Locations .......................... 31
Figure 3.1 Wind Rose for Upper Coastal Plain Res Stn ............................................................... 36
Figure 6.1 Halifax County Cancer Risk, 2014NATA* ................................................................. 54
Figure 6.2 Northampton County Cancer Risk, 2014NATA* ....................................................... 54
Table of Tables
Table 1.1 Current National Ambient Air Quality Standards and Designations .............................. 2
Table 1.2 Ozone and PM2.5 Design Values for Leggett Monitor, Edgecombe County, North
Carolina ........................................................................................................................................... 3
Table 2.1 2014 NEI v1 Nitrogen Oxide Emissions (tons) .............................................................. 7
Table 2.2 2014 NEI v1 PM2.5-Primary Emissions (tons) ................................................................ 8
Table 2.3 2014 NEIv1 SO2 Emissions (tons).................................................................................. 9
Table 2.4 2014 NEIv1 Carbon Monoxide Emissions (tons) ......................................................... 10
Table 2.5 2014 NEIv1 VOC Emissions (tons).............................................................................. 11
Table 2.6 2014 NEIv1 Ammonia Emissions (tons) ...................................................................... 12
Table 2.7 2014 NEIv1 Total HAP Emissions (pounds) ................................................................ 13
Table 2.8 HAP Emissions from Air Permitted Sources ................................................................ 14
Table 2.9 Toxic Air Pollutants Summary ..................................................................................... 18
Table 2.10 Number and Acres Burned for 2014 Prescribed Fires ................................................ 26
Table 2.11 Number and Acres Burned for 2014 Wildfires ........................................................... 27
Table 2.12 Number and Acres Burned for 2015 Prescribed Fires ................................................ 28
Table 2.13 Number and Acres Burned for 2015 Wilfires ............................................................. 29
Table 2.14 Number and Acres Burned for 2016 Prescribed Fires ................................................ 30
Table 2.15 Number and Acres Burned for 2016 Wilfires ............................................................. 31
Table 2.16 Northampton Compressor Station .............................................................................. 32
Table 2.17 ACP Pipeline Miles & Distribution of Fugitive Emissions in Area of Interest .......... 33
Table 2.18 County Level 2014 GHG Emissions (tons CO2e) ...................................................... 34
Table 2.19 2014 Total GHG Emissions in the Area of Interest (tons CO2e) ................................ 34
Table 6.1 Air Toxic Pollutants Included in NATA ....................................................................... 55
Table 6.2 Pollutants Excluded from NATA ................................................................................. 59
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 1
Air Quality Monitoring Data
"Ambient air" is the outside air that we all breathe. This term is specifically defined by the EPA
as "that portion of the atmosphere, external to buildings, to which the general public has access."
In the early 1970s, the EPA listed six major air pollutants that affected the quality of ambient air
and established concentration limits for these pollutants. These limits are known as the National
Ambient Air Quality Standards (NAAQS). Primary limits or standards were established to
protect human health and secondary standards were established to protect human welfare and the
quality of life. Through the years, the NAAQS have been revised and amended to account for
evolving scientific understanding of air pollution and its impacts. Currently, the six criteria
pollutants are:
Ozone (O3)
Particulate Matter (PM2.5 and PM10)
Carbon Monoxide (CO)
Sulfur Dioxide (SO2)
Nitrogen Dioxide (NO2)
Lead (Pb)
These six pollutants can cause serious human health problems (including premature mortality)
and damage the environment and property. Common sources of these pollutants are coal-fired
power plants, industrial manufacturing sources, and on-road and off-road vehicles. In Table 1.1,
we have listed the current NAAQS standards and the attainment designation status for each of
the six criteria pollutants in Halifax and Northampton County.
Table 1.2 contains design value data -- a statistic that describes the air quality status of a given
location relative to the level of the National Ambient Air Quality Standards (NAAQS) -- from
the closest monitor to Halifax and Northampton County (Leggett Monitor, Edgecombe County,
NC) for both ozone and PM2.5.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 2
Table 1.1 Current National Ambient Air Quality Standards and Designations
Pollutant Standard* Form of Standard
Designations
Halifax
County
Northampton
County
2008 8-Hour Ozone 75 ppb
Annual fourth-highest daily
maximum 8-hr concentration,
averaged over 3 consecutive years
Unclassifiable/
Attainment
Unclassifiable/
Attainment
2015 8-Hour Ozone 70 ppb
Annual fourth-highest daily
maximum 8-hr concentration,
averaged over 3 consecutive years
Unclassifiable/
Attainment
Unclassifiable/
Attainment
2011 1-Hour CO 35 ppm Not to be exceeded more than once
per year
Unclassifiable/
Attainment
Unclassifiable/
Attainment
2011 8-Hour CO 9 ppm Not to be exceeded more than once
per year
Unclassifiable/
Attainment
Unclassifiable/
Attainment
2008 Rolling 3-Month
Average Lead 0.15 µg/m3 Not to be exceeded Unclassifiable/
Attainment
Unclassifiable/
Attainment
2010 1-Hour NO2 100 ppb
98th percentile of 1-hour daily
maximum concentrations, averaged
over 3 consecutive years
Unclassifiable/
Attainment
Unclassifiable/
Attainment
2012 24-hour PM2.5 35 µg/m3 98th percentile, averaged over 3
years
Unclassifiable/
Attainment
Unclassifiable/
Attainment
2012 Annual PM2.5 12 µg/m3 Annual mean, averaged over 3
years
Unclassifiable/
Attainment
Unclassifiable/
Attainment
2012 24-Hour PM10 150 µg/m3 Not to be exceeded more than once
per year on average over 3 years
Unclassifiable/
Attainment
Unclassifiable/
Attainment
2010 1-Hour SO2 75 ppb
99th percentile of 1-hour daily
maximum concentrations, averaged
over 3 years
Unclassifiable/
Attainment
Unclassifiable/
Attainment
* ppm = parts per million, ppb = parts per billion, µg/m3 = micrograms per cubic meter.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 3
Table 1.2 Ozone and PM2.5 Design Values for Leggett Monitor, Edgecombe County, North
Carolina
Pollutant Design Value (ppm)
7-May 8-Jun 9-Jul 10-Aug 11-Sep 12-Oct 13-Nov 14-Dec 13-15 14-16
Ozone 8-
Hour
Average 77 76 73 71 70 71 69 65 62 62
(ppb)
PM2.5 24-
Hour
Average 27 25 22 21 20 20 19 N/A** N/A** N/A**
(µg/m3)
PM2.5
Annual
Average 12.4 11.8 10.4 9.8 9.1 8.9 8.3 N/A** N/A** N/A**
(µg/m3)
* ppb = parts per billion, µg/m3 = micrograms per cubic meter.
** Completeness issues in 2014 prevented an annual or daily PM2.5 design value from being computed for any year
in which 2014 was a part of the calculation. However, the 2015 and 2016 readings that would be used to compute
the design value did not exceed the annual or daily PM2.5 NAAQS.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 4
1.1 Satellite Imagery Data
There is more than one way to gather data on air pollution. The most accurate and reliable way is
by using surface monitors to specifically measure a given pollutant (see Table 1.2). In addition,
satellite-derived pollutant data is a great approximation of inter-year pollution trends, especially
for areas where monitoring data is sparse.
Satellites measure air pollution by averaging the depth of a given pollutant within a column of air
that comprises the entire troposphere, or bottom layer of the atmosphere. The following images
show satellite-derived pollutant concentrations for NO2, SO2, CO, and Aerosol Optical Depth
(AOD) spanning Virginia and the Carolinas for 2008 and 2016.1 A circle on each image
identifies the area of the proposed location for the Northampton Compressor Station. For each of
the four pollutants, the image on the left represents the average of daily satellite readings across
the entire calendar year of 2008, while the image on the right represents the same for the
calendar year of 2016. All of the images come from satellites operated by NASA, and the data is
freely available at the link: https://giovanni.gsfc.nasa.gov/giovanni/. Units of measurement vary
by pollutant, but the scale for each pollutant has been kept the same for the 2008 and 2016
images to show the satellite-derived evolution of the given pollutant over recent years. Warmer
colors represent higher pollutant concentrations, while cooler colors represent lower pollutant
concentrations.
As the following maps show, pollutant concentrations have decreased across the board between
2008 and 2016, both in the immediate area of the ACP compressor station and across the rest of
the Carolinas. The satellite data is consistent with surface monitor readings over Virginia and the
Carolinas, which also show significant decreases during this time.
NO2, 2008 NO2, 2016
1 Aerosol Optical Depth (AOD) is a collection of a number of particle pollutants, and serves as a general indicator of
overall particle pollution.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 5
SO2, 2008 SO2, 2016
CO, 2008 CO, 2016
AOD, 2008 AOD, 2016
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 6
Air Emissions Source Categorization
This section displays maps showing sources of air pollution reported by permitted facilities in the
North Carolina and Virginia areas of interest. The North Carolina area of interest includes all of
Northampton and Halifax counties while the Virginia area of interest includes the southern
portion of Brunswick, Greensville, and Southampton counties where large sources may have the
potential to affect air quality in Northampton and/or Halifax County. Partial Virginia counties
include the portion of each county (Brunswick, Greensville, or Southampton County) that
extends approximately 16.5-miles north of the North Carolina-Virginia state line.
The section also shows estimates of oxides of nitrogen (NOx), particulate matter with an
aerodynamic diameter less than or equal to 2.5 micrometers (PM2.5), sulfur dioxide (SO2), carbon
monoxide (CO), volatile organic compound (VOC), ammonia (NH3), federal hazardous air
pollutant (HAP), state toxic air pollutant (TAP), and greenhouse gas (GHG) emissions for the
area of interest as well as the Northampton County compressor station. The emissions data
reported for the compressor station are the expected emissions outlined in the facility’s permit
application. Although the specific source of the emissions data for each pollutant is identified in
the individual pollutant sections, the most common source is Version 1 of the 2014 National
Emissions Inventory (2014 NEIv1).2 For the tabular emissions summaries, the emissions
reported for the partial Virginia counties were estimated by multiplying county totals by the ratio
of land area in the area of interest to the total county land area. Each pollutant is broken down
by sector and county (or portion of county). The individual sectors are defined below.
Electricity Generating Unit (EGU) – permitted, stationary combustion sources such as boilers
and turbines that generate electricity for sale on the power grid.
Non-EGU Point – permitted, stationary industrial, commercial, and institutional facilities.
Nonpoint – stationary sources that individually are too small in magnitude/too numerous to
inventory as individual point sources.
Fires – includes both prescribed burning and wildfires.
Onroad – all motor vehicles that are licensed to use public roads. Onroad vehicles include
passenger cars, motorcycles, and various classes of trucks and buses categorized according to
vehicle weight and drive cycle characteristics.
Nonroad – mobile vehicles and equipment that are not licensed to use public roads, which
includes aircraft, commercial and recreational marine vessels, locomotives, and lawn and garden,
construction, and recreational equipment as well as many other types of equipment.
Biogenics – natural sources, such as vegetation (plants and trees) and microbial activity in soils.
2 United States Environmental Protection Agency, “Air Emissions Inventories, 2014 National Emissions Inventory (NEI)
Data,” available from https://www.epa.gov/air-emissions-inventories/2014-national-emissions-inventory-nei-data,
accessed January 2018.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 7
2.1 Nitrogen Oxide (NOx) Emissions
Figure 2.1 Northampton Compressor Station Area – NOx Emitting Facilities
Table 2.1 2014 NEI v1 Nitrogen Oxide Emissions (tons)
NC Counties of Interest VA Counties of Interest (Partial) Total Area
Sector Halifax Northampton Brunswick Greensville Southampton of Interest
EGU 1,016 0 96 0 84 1,197
Non-EGU Point 1,467 206 5 190 86 1,953
Nonpoint 89 30 19 21 26 184
Fires 8 0 16 10 7 40
Onroad 1,267 485 569 708 629 3,659
Nonroad 560 347 37 263 215 1,422
Biogenics 237 180 56 55 112 641
Total 4,644 1,248 798 1,246 1,159 9,095
Compressor Station 19 19
Total with Station 1,268 9,114
Northampton County Emissions
Increase (%) 2% Area of Interest Emissions Increase (%) 0.2%
Source of Data: EPA 2014 NEIv1
Notes: a new EGU came on-line in Brunswick County in the 2nd quarter of 2016 (NOx emissions = 127.2 tons)
for NC in 2016, EGU emissions decreased by 868 tons and non-EGU point emissions decreased by 151 tons
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 8
2.2 Fine Particulate Matter (PM2.5) Emissions
Figure 2.2 Northampton Compressor Station Area – PM2.5 Emitting Facilities
Table 2.2 2014 NEI v1 PM2.5-Primary Emissions (tons)
NC Counties of Interest VA Counties of Interest (Partial) Total Area
Sector Halifax Northampton Brunswick Greensville Southampton of Interest
EGU 12 0 44 0 3 60
Non-EGU Point 199 135 1 132 6 473
Nonpoint 534 620 121 153 337 1,764
Fires 34 0 64 40 29 167
Onroad 32 14 17 20 21 104
Nonroad 33 19 4 12 14 82
Biogenics 0 0 0 0 0 0
Total 844 788 250 358 410 2,649
Compressor Station 18 18
Total with Station 806 2,667
Northampton County Emissions
Increase (%) 2%
Area of Interest Emissions
Increase (%) 0.7%
Source of Data: EPA 2014 NEIv1
Notes: a new EGU came on-line in Brunswick County in the 2nd quarter of 2016 (PM2.5-PRI emissions not yet available)
for NC in 2016, EGU emissions decreased by 4 tons and non-EGU point emissions decreased by 147 tons
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 9
2.3 Sulfur Dioxide (SO2) Emissions
Figure 2.3 Northampton Compressor Station Area – SO2 Emitting Facilities
Table 2.3 2014 NEIv1 SO2 Emissions (tons)
NC Counties of Interest VA Counties of Interest (Partial) Total Area
Sector Halifax Northampton Brunswick Greensville Southampton of Interest
EGU 377 0 2 0 5 384
Non-EGU Point 78 33 2 23 5 141
Nonpoint 21 8 5 4 7 45
Fires 4 0 7 4 3 18
Onroad 4 2 2 2 3 13
Nonroad 4 2 0 2 1 10
Biogenics 0 0 0 0 0 0
Total 488 45 17 37 24 611
Compressor Station 3 3
Total with Station 48 614
Northampton County Emissions
Increase (%) 6%
Area of Interest Emissions
Increase (%) 0.5%
Source of Data: EPA 2014 NEIv1
Notes: a new EGU came on-line in Brunswick County in the 2nd quarter of 2016 (SO2 emissions = 12.6 tons)
for NC in 2016, EGU emissions decreased by 347 tons and non-EGU point emissions increased by 5 tons
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 10
2.4 Carbon Monoxide (CO) Emissions
Figure 2.4 Northampton Compressor Station Area – CO Emitting Facilities
Table 2.4 2014 NEIv1 Carbon Monoxide Emissions (tons)
NC Counties of Interest VA Counties of Interest (Partial) Total Area
Sector Halifax Northampton Brunswick Greensville Southampton of Interest
EGU 532 0 114 0 170 816
Non-EGU Point 812 312 18 860 198 2,199
Nonpoint 554 306 219 156 301 1,536
Fires 367 4 681 435 308 1,794
Onroad 6,010 2,278 1,544 1,890 1,991 13,713
Nonroad 2,042 819 270 444 636 4,211
Biogenics 1,902 1,502 965 752 1,048 6,169
Total 12,218 5,220 3,811 4,537 4,652 30,439
Compressor Station 31 31
Total with Station 5,251 30,470
Northampton County Emissions
Increase (%) 1%
Area of Interest Emissions
Increase (%) 0.1%
Source of Data: EPA 2014 NEIv1
Notes: a new EGU came on-line in Brunswick County in the 2nd quarter of 2016 (CO emissions not yet available)
for NC in 2016, EGU emissions decreased by 485 tons and non-EGU point emissions increased by 99 tons
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 11
2.5 Volatile Organic Compounds (VOC) Emissions
Figure 2.5 Northampton Compressor Station Area – VOC Emitting Facilities
Table 2.5 2014 NEIv1 VOC Emissions (tons)
NC Counties of Interest VA Counties of Interest (Partial) Total Area
Sector Halifax Northampton Brunswick Greensville Southampton of Interest
EGU 9 0 59 0 5 73
Non-EGU Point 389 590 6 69 123 1,177
Nonpoint 863 315 168 236 224 1,806
Fires 87 1 162 104 74 428
Onroad 604 223 153 166 201 1,346
Nonroad 219 105 33 81 92 531
Biogenics 14,875 11,526 7,698 5,778 7,850 47,726
Total 17,047 12,760 8,280 6,433 8,568 53,088
Compressor Station 21 21
Total with Station 12,781 53,109
Northampton County Emissions
Increase (%) 0.2%
Area of Interest Emissions
Increase (%) 0.0%
Source of Data: EPA 2014 NEIv1
Notes: a new EGU came on-line in Brunswick County in the 2nd quarter of 2016 (VOC emissions not yet available)
for NC in 2016, EGU emissions decreased by 8 tons and non-EGU point emissions decreased by 187 tons
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 12
2.6 Ammonia Emissions
Table 2.6 2014 NEIv1 Ammonia Emissions (tons)
NC Counties of Interest VA Counties of Interest (Partial) Total Area
Sector Halifax Northampton Brunswick Greensville Southampton of Interest
EGU 7 0 0 0 1 8
Non-EGU Point 28 15 0 8 1 53
Nonpoint 730 1,853 188 64 548 3,382
Fires 6 0 11 7 5 30
Onroad 27 11 8 11 10 67
Nonroad 0 0 0 0 0 1
Biogenics 0 0 0 0 0 0
Total 798 1,879 207 90 566 3,541
Compressor Station 12 12
Total with Station 1,892 3,553
Northampton County Emissions
Increase (%) 1%
Area of Interest Emissions
Increase (%) 0.3%
Source of Data: EPA 2014 NEIv1
Notes: a new EGU came on-line in Brunswick County in the 2nd quarter of 2016 (NH3 emissions not yet available)
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 13
2.7 Federal Hazardous Air Pollutants (HAPs)
Table 2.7 2014 NEIv1 Total HAP Emissions (pounds)
NC Counties of Interest VA Counties of Interest (Partial) Total Area
Sector Halifax Northampton Brunswick Greensville Southampton of Interest
EGU 10,920 0 2,473 0 29,444 42,837
Non-EGU Point 365,167 270,669 4,207 42,818 130,653 813,514
Nonpoint 162,498 74,323 57,500 65,367 84,773 444,459
Fires 36,889 492 73,950 43,511 32,373 187,216
Onroad 328,225 121,518 80,028 85,929 107,168 722,868
Nonroad 137,127 65,499 22,211 49,011 59,697 333,544
Biogenics 3,048,244 2,412,582 1,539,166 1,210,539 1,662,913 9,873,444
Total 4,089,069 2,945,083 1,779,535 1,497,176 2,107,021 12,417,883
Compressor Station 4,712 4,712
Total with Station 2,949,795 12,422,595
Northampton County Emissions
Increase (%) 0.2%
Area of Interest Emissions
Increase (%) 0.0%
Source of Data: EPA 2014 NEIv1
Notes: a new EGU came on-line in Brunswick County in the 2nd quarter of 2016 (HAP emissions not yet available)
for NC in 2016, EGU emissions decreased by 9,591 lbs and non-EGU point emissions increased by 73,486 lbs
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 14
Table 2.8 HAP Emissions from Air Permitted Sources
CAS Pollutant Name
Counties in Area of Interest
Total
(lbs/yr)
Modeled
Compressor
Station
emissions
(lbs/yr)
% Increase in
Northampton
County
Emissions
% Increase
in Area of
Interest
Emissions
Halifax
(lbs/yr)
Northampton
(lbs/yr)
Brunswick,
Greensville
and
Southampton
(lbs/yr)
100-02-7 Nitrophenol, 4- 0.08 0.13 0.21
100-41-4 Ethyl benzene 232.77 268.94 259.45 761.16 0.27 0.10% 0.04%
100-42-5 Styrene 3676.87 1799.97 26.04 5502.88 0.14 0.01% 0.00%
100-44-7 Benzyl chloride 204.10 105.67 309.77
106-42-3 Xylene, p- 1143.06 1143.06
106-46-7 Dichlorobenzene(p), 1,4- 0.04 0.02 0.06 0.06 >100% 85.05%
106-51-4 Quinone 12.54 12.54
106934 Ethylene Dibromide 0.18 0.18 0.18 101.57%
106-99-0 Butadiene, 1,3- 4.97 0.00 4.97 2.05 >100% 41.25%
107-02-8 Acrolein 1378.32 5474.51 900.32 7753.15 19.47 0.36% 0.25%
107-06-2 Ethylene dichloride (1,2-dichloroethane) 12.11 20.61 48.26 80.98 0.11 0.51% 0.13%
107-13-1 Acrylonitrile 1.08 1.08
108-05-4 Vinyl acetate 0.00 1.15 1.15
108-10-1 MIBK (methyl isobutyl ketone) 1487.76 1679.37 3167.13
108-38-3 Xylene, m- 0.48 400.56 401.04
108-39-4 Cresol, m- 2.00 2.00
108-88-3 Toluene 2227.04 1005.26 2171.90 5404.19 2.57 0.26% 0.05%
108-90-7 Chlorobenzene 36.00 23.45 27.33 86.78 0.11 0.47% 0.13%
108-95-2 Phenol 2071.17 19402.60 6134.89 27608.67 0.11 0.00% 0.00%
110-54-3 Hexane, n- 979.60 255.90 878.27 2113.76 84.07 >100% >100%
117-81-7 DEHP (Di(2-ethylhexyl)phthalate) 30.89 0.03 11.02 41.94
120-82-1 Trichlorobenzene, 1,2,4- 15.91 0.03 15.94
121448 Triethylamine 59556.00 59556.00
123-38-6 Propionaldehyde 2084.80 917.35 293.51 3295.67
127-18-4 Perchloroethylene (tetrachloroethylene) 23.71 27.01 126.49 177.21
131-11-3 Dimethyl phthalate 0.00 0.00
1319-77-3 Cresol (mixed isomers) 1251.00 92.40 1343.40
132-64-9 Furans - Dibenzofurans 0.16 0.16
1330-20-7 Xylene (mixed isomers) 8945.69 144.00 733.50 9823.20 0.67 0.47% 0.01%
1336-36-3 PCB (polychlorinated biphenyls) 0.01 0.01
140-88-5 Ethyl acrylate 2.08 2.08
1634-04-4 Methyl tertiary butyl ether (MTBE) 9.48 5.28 14.76
463-58-1 Carbonyl sulfide 51.42 20.00 71.42
50-00-0 Formaldehyde 6309.05 54165.05 3629.47 64103.58 2893.09 5.34% 4.51%
50-32-8 Benzo(a)pyrene 0.00 1.85 0.01 1.86
51-28-5 Dinitrophenol, 2,4- 0.13 0.19 0.32
532-27-4 Chloroacetophenone, 2- 2.04 1.06 3.10
540-84-1 Trimethylpentane, 2,2,4- 4.65 3140.00 3144.65 2.12 >100% 0.07%
56-23-5 Carbon tetrachloride 27.07 31.98 16.77 75.82 0.03 0.10% 0.04%
60-34-4 Methyl hydrazine 49.57 28791.57 28841.14
62-53-3 Aniline 129.21 129.21
67-56-1 Methanol (methyl alcohol) 269231.22 154814.48 28791.57 452837.27 5.78 0.00% 0.00%
67-66-3 Chloroform 28.23 19.90 12.59 60.73 0.12 0.59% 0.19%
71-43-2 Benzene 1529.10 3006.57 687.82 5223.49 4.86 0.16% 0.09%
71-55-6 Methyl chloroform 0.13 22.03 38.46 60.62
74-83-9 Methyl bromide (bromomethane) 47.38 10.66 24.15 82.19
74-87-3 Methyl chloride (chloromethane) 267.19 16.35 109.80 393.33
74-88-4 Methyl iodide (iodomethane) 3.96 3.96
75-00-3 Ethyl chloride (chloroethane) 12.27 6.34 18.61
75-01-4 Vinyl chloride 2.00 12.79 86.61 101.40 0.06 0.48% 0.06%
75-07-0 Acetaldehyde 45069.02 12945.21 9417.52 67431.76 19.42 0.15% 0.03%
75-09-2 Methylene chloride 1349.14 206.10 144.56 1699.80 0.37 0.18% 0.02%
75-15-0 Carbon disulfide 556.55 19.62 576.17
75-25-2 Bromoform 11.37 5.89 17.26
75-56-9 Propylene oxide 18.52 18.52
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 15
CAS Pollutant Name
Counties in Area of Interest
Total
(lbs/yr)
Modeled
Compressor
Station
emissions
(lbs/yr)
% Increase in
Northampton
County
Emissions
% Increase
in Area of
Interest
Emissions
Halifax
(lbs/yr)
Northampton
(lbs/yr)
Brunswick,
Greensville
and
Southampton
(lbs/yr)
7647-01-0 Hydrogen chloride (hydrochloric acid) 14449.63 13503.29 96591.14 124544.06
7664-39-3 Hydrogen fluoride 3252.67 833.00 4085.67
7723-14-0 Phosphorus Metal, Yellow or White 1287.91 19.19 18.87 1325.97
7738-94-5 Chromic acid (VI) 355.37 355.37
77-78-1 Dimethyl sulfate 14.00 7.25 21.24
7782-50-5 Chlorine 211.83 561.45 1024.66 1797.94
78-59-1 Isophorone 178.55 87.55 266.10
78-87-5 Propylene dichloride (1,2-dichloropropane) 23.45 66039.00 66062.45 0.11 0.47% 0.00%
79-00-5 Trichloroethane, 1,1,2- 178.53 178.53 0.13 >100% 0.07%
79-01-6 TCE (trichloroethylene) 30.00 21.32 80.00 131.32
84-74-2 Dibutylphthalate 5.44 5.44
87-86-5 Pentachlorophenol 0.04 0.11 0.15
88-06-2 Trichlorophenol, 2,4,6- 0.02 0.39 0.41
91-20-3 Naphthalene 124.37 181.27 134.27 439.91 0.27 0.15% 0.06%
92-52-4 Biphenyl 1.95 0.26 2.21 0.01 >100% 0.45%
95-47-6 Xylene, o- 0.14 0.14
95-48-7 Cresol, o- 0.18 0.18
95-53-4 Toluidine, o- 0.00 0.00
98-82-8 Cumene 910.89 219.34 0.80 1131.02
98-86-2 Acetophenone 21.66 0.00 1769.41 1791.07
ASC
(7778394)
Arsenic & Compounds (total mass of
elemental AS, arsine and all inorganic
compounds) 295.58 15.67 7.19 318.45 0.01 0.06% 0.00%
BEC Beryllium & compounds (Total mass) 5.46 0.78 0.27 6.51 0.00 0.13% 0.02%
CDC
Cadmium & compounds (total mass
includes elemental metal) 24.66 2.92 4.56 32.14 0.05 1.75% 0.16%
CNC
Cyanide & compounds (see also hydrogen
cyanide) 728.92 377.39 1106.31
COC Cobalt & compounds 22.47 4.62 10.46 37.55 0.00 0.09% 0.01%
CRC
Chromium - All/Total (includes Chromium
(VI) categories, metal and others) 440.80 12.45 29.19 482.44 0.06 0.52% 0.01%
16065831 Chromium III 15.12
18540299 Chromium (VI) 14.07
GLYET
Glycol ethers (total all individual glycol
ethers) 8985.00 8985.00
HGC
Mercury & Compounds - all total mass
includes Hg Vapor 29.36 2.52 2.25 34.13 0.01 0.49% 0.04%
MNC Manganese & compounds 691.82 1137.28 334.87 2163.97 0.02 0.00% 0.00%
NIC
Nickel & Compounds, sum total mass
includes elemental 217.17 23.52 16.14 256.83 0.10 0.41% 0.04%
PBC Lead & compounds 95.72 34.13 0.25 130.10 0.02 0.07% 0.02%
POM Polycyclic Organic Matter 107.70 96.31 204.01 0.34 0.35% 0.17%
SBC
Antimony & Compounds (total mass, inc
elemental SB) 162.69 5.61 2.46 170.76
SEC Selenium Compounds 486.42 1.99 4.34 492.75 0.00 0.05% 0.00%
Sum 382694.03 272108.55 315308.12 970110.70 3036.78 1.12% 0.31%
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 16
2.8 State Toxic Air Pollutants
The Clean Air Act amendments of 1990 originally identified 189 Hazardous Air Pollutants, or
HAPs, for regulation. HAPs are pollutants "known to cause or may reasonably be anticipated to
cause adverse effects to human health or adverse environmental effects" [Section 112 (b)]. There
are currently 187 federal HAPs following the delisting of caprolactam in 1996 and methyl ethyl
ketone in 2005.
HAPs may be emitted from stationary sources (industrial processes) or mobile sources (cars,
trucks and other vehicles).
North Carolina has a health-based toxic air pollutant control program that regulates 97 Toxic Air
Pollutants or TAPs. The North Carolina Air Toxics program focuses on chemicals emitted by
stationary sources. Twenty (20) of the 97 North Carolina TAPs are not classified as HAPs while
77 pollutants are common to both lists.
The tables that follow quantify the HAPs and TAPs emitted in the area of interest currently and
the potential impact of the emissions of the Northampton Compressor Station to this area.
Graphs of HAP and TAP emissions from 1993 to 2015 are a visual representation of pollutant
trends for the area.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 17
Figure 2.6 Statewide Toxic Pollutant Totals Trend (1993-2015)
Figure 2.7 Halifax and Northampton Counties Toxic Pollutants Totals Trends (1993-2015)
0
20,000,000
40,000,000
60,000,000
80,000,000
100,000,000
120,000,000
140,000,000
160,000,000
19931994199519961997199819992000200120022003200420052006200720082009201020112012201320142015Statewide Total Toxic Emissions in pounds per yearHAP+TAP totals TAP totals HAP totals
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
1,400,000
1,600,000
1,800,000
19931994199519961997199819992000200120022003200420052006200720082009201020112012201320142015Total Toxic Emissions in pounds per yearHAP+TAP totals TAP totals HAP totals
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 18
Figure 2.8 Toxic Pollutants Trends by County (1993-2015)
Table 2.9 Toxic Air Pollutants Summary
Total for 6
TAPs (lbs/yr)
% State
Total for 6
TAPs
State Total for
all TAPs (lbs/yr)
% State
Total for all
TAPs
Halifax 520,426.65 7.59% 2.31%
Northampton 257.26 0.00% 0.00%
Total for two counties 520,683.91
State total 6,858,299.75 7.59% 22,547,189.69 2.31%
Compressor Station 0.00 0.00
Total with Station 520,683.91 7.59% 22,547,189.69 2.31%
Fluorides
Methyl
mercaptan Sulfuric acid
Hydrogen
Sulfide
Methyl ethyl
ketone
Hexachlorodibenzo-
p-dioxin 1,2,3,6,7,8
16984-48-8 74-93-1 7664-93-9 7783-06-4 78-93-3 57653-85-7
(lbs/yr) (lbs/yr) (lbs/yr) (lbs/yr) (lbs/yr) (lbs/yr)
Halifax 4,268.16 4,846.16 50,393.06 443,419.13 17,500.14
Northampton 1.13 256.13 0.00002
Total for two counties 4,268.16 4,846.16 50,393.06 443,420.26 17,756.27 0.00002
State total 666,384.73 357,399.12 2,472,453.46 2,319,813.41 1,042,245.85 3.19
% of State Total 0.64% 1.36% 2.04% 19.11% 1.70% 0.00%
Notes:
TAP only emissions includes all toxic air pollutants except Ammonia (CAP) emissions which are included in the 2014 NEI
Listed TAP only emissions are the TAP emissions reported for these two counties that are not also HAPs.
Represents emissions data for 97 counties administered by NCDAQ.
0
200,000
400,000
600,000
800,000
1,000,000
1,200,000
1,400,000
19931994199519961997199819992000200120022003200420052006200720082009201020112012201320142015Total Toxic Emissions in pounds per yearHalifax HAP+TAP Totals Northampton HAP+TAP Totals
Halifax TAP Totals Northampton TAP Totals
Halifax HAP Totals Northampton HAP Totals
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 19
2.9 North Carolina and Virginia Power Plant Emissions Data
The following charts show calendar year 2014 daily emissions of NOx, SO2 and CO2 in tons
from the five large electricity generating facilities in North Carolina and Virginia. Roanoke
Valley I and II, located in North Carolina, are coal-fired cogeneration units that provide both
steam for industrial use and electrical power to the grid on a contractual basis. In recent years,
they have been contracted to provide power during peak demand hours. Future operations are
not clear since the units changed ownership in January of 2018. Rosemary Power Station
operates two natural gas-fired units that also are located in North Carolina and provide power
during peak demand hours. Since all three facilities in North Carolina provided peak demand
power in 2014, the emissions data shown in the charts is very intermittent. Southampton County
Power Station is located in Virginia and was converted from coal to biomass in 2013.
Brunswick County Power Station is a new natural gas combined cycle plant that came online in
April of 2016, therefore the emissions data presented for this facility is from April to December
of 2016 rather than calendar year 2014 emissions.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 20
Figure 2.9 Westmoreland Partners Roanoke Valley I Facility Level 2014 Daily SO2
Emissions (tons)
Figure 2.10 Westmoreland Partners Roanoke Valley I Facility Level 2014 Daily NOx
Emissions (tons)
Figure 2.11 Westmoreland Partners Roanoke Valley I Facility Level 2014 Daily CO2
Emissions (tons)
0
1
2
3
4
5
6
7
8
1/1/2014 2/20/2014 4/11/2014 5/31/2014 7/20/2014 9/8/2014 10/28/2014 12/17/2014SO2 (ton/day)Date
Avg Daily:2.48 ton/day
Max. Daily: 7.43 ton/day (9/11)
0
1
2
3
4
5
6
7
1/1/2014 2/20/2014 4/11/2014 5/31/2014 7/20/2014 9/8/2014 10/28/2014 12/17/2014NOx(ton/day)Date
Avg. Daily:4.15 ton/day
Max Daily: 6.38 ton/day (2/4)
0
500
1000
1500
2000
2500
3000
3500
4000
4500
1/1/2014 2/20/2014 4/11/2014 5/31/2014 7/20/2014 9/8/2014 10/28/2014 12/17/2014CO2 (ton/day)Date
Avg. Daily: 2,799 ton/day
Max. daily: 4,023 ton/day (2/24)
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 21
Figure 2.12 Westmoreland Partners Roanoke Valley II Facility Level 2014 Daily SO2
Emissions (tons)
Figure 2.13 Westmoreland Partners Roanoke Valley II Facility Level 2014 Daily NOx
Emissions (tons)
Figure 2.14 Westmoreland Partners Roanoke Valley II Facility Level 2014 Daily CO2
Emissions (tons)
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8
2
1/1/2014 2/20/2014 4/11/2014 5/31/2014 7/20/2014 9/8/2014 10/28/2014 12/17/2014SO2 (ton/day)Date
Avg. Daily: 0.42 ton/day
Max.Daily: 1.82 ton/day (6/17)
0
0.2
0.4
0.6
0.8
1
1.2
1/1/2014 2/20/2014 4/11/2014 5/31/2014 7/20/2014 9/8/2014 10/28/2014 12/17/2014NOx (ton/day)Date
Avg.Daily: 0.73 ton/day
Max. daily: 1.99 ton/day (1/7)
0
200
400
600
800
1000
1200
1400
1/1/2014 2/20/2014 4/11/2014 5/31/2014 7/20/2014 9/8/2014 10/28/2014 12/17/2014CO2 (ton/day)Date
Avg. Daily:900 ton/day
Max. Daily: 1,181 ton/day (2/14)
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 22
Figure 2.15 Rosemary Power Station Facility Level 2014 Daily SO2 Emissions (tons)
Figure 2.16 Rosemary Power Station Facility Level 2014 Daily NOx Emissions (tons)
Figure 2.17 Rosemary Power Station Facility Level 2014 Daily CO2 Emissions (tons)
0
0.5
1
1.5
2
2.5
1/1/2014 2/20/2014 4/11/2014 5/31/2014 7/20/2014 9/8/2014 10/28/2014 12/17/2014SO2(ton/day)Date
Avg. Daily: 0.39 ton/day
Max. daily: 2.14 ton/day (1/29)
0
0.5
1
1.5
2
2.5
3
3.5
4
4.5
5
1/1/2014 2/20/2014 4/11/2014 5/31/2014 7/20/2014 9/8/2014 10/28/2014 12/17/2014NOx(ton/day)Date
Avg. Daily: 1.16 ton/day
Max. Daily: 4.30 ton/day (1/30)
0
500
1000
1500
2000
2500
3000
3500
1/1/2014 2/20/2014 4/11/2014 5/31/2014 7/20/2014 9/8/2014 10/28/2014 12/17/2014CO2 (ton/day)Date
Avg. Daily:898 ton/day
Max. Daily: 3,048.5 ton/day (1/24)
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 23
Figure 2.18 Southampton Power Station Facility Level 2014 Daily SO2 Emissions (tons)
Figure 2.19 Southampton Power Station Facility Level 2014 Daily NOx Emissions (tons)
Figure 2.20 Southampton Power Station Facility Level 2014 Daily CO2 Emissions (tons)
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
1/1/2014 3/2/2014 5/1/2014 6/30/2014 8/29/2014 10/28/2014 12/27/2014SO2 (ton/day)Average Daily : 0.04 ton/day
Max Daily: 0.06 ton/day (12/2)
0
0.2
0.4
0.6
0.8
1
1.2
1.4
1/1/2014 3/2/2014 5/1/2014 6/30/2014 8/29/2014 10/28/2014 12/27/2014NOx (ton/day)Average Daily : 0.78 ton/day
Max Daily: 1.16 ton/day (12/22)
0
200
400
600
800
1000
1200
1400
1600
1800
2000
1/1/2014 3/2/2014 5/1/2014 6/30/2014 8/29/2014 10/28/2014 12/27/2014CO2 (ton/day)Average Daily: 1,408 ton/day
Max Daily: 1,867 ton/day (12/23)
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 24
Figure 2.21 Brunswick Power Station Facility Level 2014 Daily SO2 Emissions (tons)
Figure 2.22 Brunswick Power Station Facility Level 2014 Daily NOx Emissions (tons)
Figure 2.23 Brunswick Power Station Facility Level 2014 Daily CO2 Emissions (tons)
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
0.08
4/14/2016 6/3/2016 7/23/2016 9/11/2016 10/31/2016 12/20/2016SO2 (ton/day)Average Daily: 0.05 ton/day
Max Daily: 0.07 ton/day (11/22)
0
0.2
0.4
0.6
0.8
1
1.2
4/14/2016 6/3/2016 7/23/2016 9/11/2016 10/31/2016 12/20/2016NOx (ton/day)Average Daily: 0.55 ton/day
Max Daily: 1.15 ton/day (11/1)
0
2000
4000
6000
8000
10000
12000
14000
4/14/2016 6/3/2016 7/23/2016 9/11/2016 10/31/2016 12/20/2016CO2 (ton/day)Average Daily: 10,818ton/day
Maximum Daily: 14,043 ton/day (11/22)
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 25
2.10 Prescribed Fires and Wildfire Events
Prescribed fires are fires that are intentionally ignited to meet specific management objectives
such as ecosystem restoration and wildfire hazard reduction. Wildfires are fires started by an
unplanned ignition caused by, for example, lightning or other acts of nature, accidental human-
caused actions, or a prescribed fire that has developed into a wildfire. These fire events generate
air pollutants (PM2.5, NOx, CO, VOC) that are tracked by North Carolina and EPA annually to
understand their overall contribution to total emissions in the state and locally.
The following maps and tables show the total number of fires and total acres burned by
prescribed fires and wildfires in the area of interest for 2014, 2015, and 2016. Data for NC and
VA for 2014 were obtained from the 2014 NEIv1. For 2015 and 2016, data were only available
from the North Carolina Forest Service.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 26
Figure 2.24 Northampton Compressor Station Area - 2014 Prescribed Fire Locations
Table 2.10 Number and Acres Burned for 2014 Prescribed Fires
2014
No. of
Prescribed
Fires
Acres
Burned
North Carolina State Total 10,927 128,547
Halifax and Northampton Counties 7 529
Percent of State Total 0.06% 0.41%
Virginia State Total 606 100,580
Brunswick, Greensville, and Southampton Counties
(Partial) 24 2160
Percent of State Total 3.96% 2.15%
Area of Interest Total 31 2689
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 27
Figure 2.25 Northampton Compressor Station Area - 2014 Wildfire Locations
Table 2.11 Number and Acres Burned for 2014 Wildfires
2014
No. of Wild
Fires Acres Burned
North Carolina State Total 2,658 25,053
Halifax and Northampton
Counties 10 36
Percent of State Total 0.38% 0.14%
Virginia State Total 877 16,774
Brunswick, Greensville, and
Southampton Counties (Partial) 11 14
Percent of State Total 1.25% 0.08%
Area of Interest Total 21 50
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 28
Figure 2.26 Northampton Compressor Station Area - 2015 Prescribed Fire Locations
Table 2.12 Number and Acres Burned for 2015 Prescribed Fires
2015
No. of
Prescribed
Fires Acres Burned
North Carolina Not Available Not Available
Halifax and Northampton
Counties 17 1271
Percent of Total Not Available Not Available
Note: 2015 fire data is not available for Virginia.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 29
Figure 2.27 Northampton Compressor Station Area - 2015 Wildfire Locations
Table 2.13 Number and Acres Burned for 2015 Wilfires
2015
No. of Wild
Fires Acres Burned
North Carolina Not Available Not Available
Halifax and Northampton
Counties 59 63
Percent of Total Not Available Not Available
Note: 2015 fire data is not available for Virginia.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 30
Figure 2.28 Northampton Compressor Station Area - 2016 Prescribed Fire Locations
Table 2.14 Number and Acres Burned for 2016 Prescribed Fires
2016
No. of
Prescribed
Fires Acres Burned
North Carolina Not Available Not Available
Halifax and Northampton
Counties 23 1632
Percent of Total Not Available Not Available
Note: 2016 fire data is not available for Virginia.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 31
Figure 2.29 Northampton Compressor Station Area - 2016 Wildfire Locations
Table 2.15 Number and Acres Burned for 2016 Wilfires
2016
No. of Wild
Fires
Acres
Burned
North Carolina Not Available
Not
Available
Halifax and Northampton
Counties 88 96
Percent of Total Not Available
Not
Available
Note: 2016 fire data is not available for Virginia.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 32
2.11 Greenhouse Gas Emissions
Greenhouse gases (GHGs) are air pollutants that trap heat in the atmosphere. The three primary
GHGs emitted by fossil and biomass fuel combustion are carbon dioxide (CO2), methane (CH4)
and nitrous oxide (N2O). Methane is also emitted as fugitive leaks from natural gas compressor
station operations and transmission of the compressed gas through the pipeline systems. Each
gas has a different atmospheric lifetime and different ability to absorb heat. Therefore, it is
common to calculate the tons of emissions of methane and nitrous oxide on the basis of carbon
dioxide. This basis is termed “as CO2 equivalent” (CO2e).
In addition, carbon dioxide that is emitted from the combustion of biomass material is considered
“carbon neutral”. This means that the emitted CO2 does not contribute to global warming since
an equivalent amount is re-sequestered by re-growing the biomass, making the net carbon
emissions equal to zero. Although many factors influence the carbon sequestration process, a
scientific consensus has not been fully developed regarding the best approach for addressing
carbon neutrality. For the purpose of this emissions inventory, we have assumed that biomass
related emissions are not included in the total GHG emissions as CO2e.
The Northampton Compressor Station GHG emissions and pipeline fugitive GHG emissions
were obtained from the latest air quality permit application and the FERC Final Environmental
Impact Statement.3 The fugitive emissions for the total project were distributed to the counties
of interest using the miles of pipeline in each county. The Atlantic Coast Pipeline emissions in
the area of interest are presented in the following two tables.
Table 2.16 Northampton Compressor Station
Project Potential Annual Emissions
Sources
CO2
(tons)
CH4
(tons)
N2O
(tons)
Total GHG
(tons CO2e)
Solar Tarus 70 Turbine 50,053 4 1.26 50,528
Solar Centaur 50L Turbine 31,329 2.5 0.788 31,626
Solar Centaur 40 Turbine 26,747 2.14 0.671 27,000
Caterpillar Egen 101 0.859 0 122
Generac Egen 759 0.015 0 759
Boiler 2,705 0.052 0.05 2,721
Fugitive Leaks Blowdowns 19.5 643 0 16,095
Fugitive Leaks- Piping 0.4 12 0 300
Fugitive Leaks - Tank 0 0 0 0
Waste Oil Tank 0 0 0 0
Compressor Station 111,714 665 2.77 129,153
3 Federal Energy Regulatory Commission (FERC) Staff Issues Final Environmental Impact Statement for the Atlantic
Coast Pipeline and Supply Header Project (CP15-554-000, -001; CP15-555-000; and CP15-556-000), Issued: July 21,
2017.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 33
Table 2.17 ACP Pipeline Miles & Distribution of Fugitive Emissions in Area of Interest
State County
Total Pipeline
Miles
Percent of
Total Pipeline
Length
Annual Fugitive VOC
Emissions
(tons)
Annual Fugitive
GHG Emissions
(tons CO2e)
NC Halifax 24.3 4.0% 0.075 66.6
Northampton 22.3 3.7% 0.069 61.1
VA Brunswick 23.0 3.8% 0.071 63.0
Greensville 18.7 3.1% 0.058 51.3
Southampton 26.3 4.4% 0.081 72.1
Area of Interest 114.6 19% 0.353 314.1
ACP System 604.5 1.86 1,657
Emissions data for each sector was obtained from several sources:
EGU and Non-EGU point source data for facilities reporting 25,000 metric tons CO2e per
year or greater obtained from the EPA 2014 Facility Level Information on Greenhouse
Gases Tool (FLIGHT)4
GHG emissions data submitted voluntarily by Non-EGU point sources to the North
Carolina Division of Air Quality through the Internet-based Enterprise Application
Management (IBEAM) and obtained from the internal 2014 North Carolina Multi-
Pollutant Inventory Database.
EPA 2014 National Emissions Inventory Version 1 for on-road mobile, nonroad mobile
and wildfires and prescribed burning.5
The following two tables present the GHG emissions from the various sectors and the
Northampton compressor station and pipeline fugitive emissions by county and for the total area
of interest.
Note that the Non-EGU point source GHG data is not complete. Only a small number of
facilities are required to report GHG emissions to EPA or opt to voluntarily report GHG
emissions to North Carolina. The GHG emissions for Non-EGU point source facilities included
in this report represents only 19 percent of the total number of these facilities reporting to the
NEI in North Carolina and Virginia. Therefore, actual GHG emissions in the area of interest are
significantly higher.
4 United States Environmental Protection Agency, “Facility Level Information on Greenhouse Gases Tool” (FLIGHT),
2014 Data for NC and VA, available from https://ghgdata.epa.gov/ghgp/main.do, accessed on January 29, 2018.
5 United States Environmental Protection Agency, “Air Emissions Invento ries, 2014 National Emissions Inventory (NEI)
Data,” available from https://www.epa.gov/air -emissions-inventories/2014-national-emissions-inventory-nei-data,
accessed January 2018.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 34
Table 2.18 County Level 2014 GHG Emissions (tons CO2e)
Source Halifax Northampton Brunswick Greensville Southampton
EGU 738,828 5,218
Non-EGU Point6 422,916 117,685 81,585 N/A N/A
Nonpoint N/A N/A N/A N/A N/A
Fires 11,555 117 38,748 16,410 13,649
On-road Mobile 331,731 141,198 235,749 194,648 233,757
Nonroad Mobile 35,278 21,090 11,738 11,820 29,076
County GHG 1,540,308 280,089 367,821 222,878 281,700
Biogenic CO2 816,028 147,135 20,859 8,485 7,412
Compressor Station 129,153
Pipeline Fugitives 67 61 63 51 72
Project GHG 67 129,214 63 51 72
Percent Increase 0.00% 46% 0.02% 0.02% 0.03%
N/A = not available
Table 2.19 2014 Total GHG Emissions in the Area of Interest (tons CO2e)
Sector CO2 CH4 N2O
Total GHG
(tons CO2e)
Biogenic
(tons CO2e)
EGU 735,000 970 8,076 744,046 0
Non-EGU Point6 470,158 145,762 6,265 622,185 957,336
Nonpoint N/A N/A N/A N/A N/A
Fires 0 80,478 0 80,478 42,583
On-road Mobile 1,136,992 1,590 8,494 1,137,084 0
Nonroad Mobile 108,207 796 0 109,003 0
Total 2,450,357 229,597 22,835 2,692,796 999,919
Compressor Station 111,714 16,614 825 129,153 0
Pipeline Fugitives 0 314 0 314 0
Project GHG 111,714 16,928 825 129,467 0
Percent Increase 4.8%
N/A = not available
6 Represents emissions from a limited number of facilities that are required to report emissions to EPA or
voluntarily reported emissions to North Carolina. Actual non-EGU emissions are expected to be significantly
higher than reported above.
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Wind Rose
A wind rose is a graphical tool used to show wind speed and wind direction for a particular
location over a specified period of time. The wind rose is divided into a number of spokes, which
represent the frequency of winds blowing from a particular direction. For example, the longest
spoke on the wind rose represents the greatest frequency of winds blowing from that particular
direction over the specified time frame.
To get the most representative wind rose for a given location, a sufficiently long period of record
is needed. After a careful review of the data from the weather stations in closest proximity to the
Northampton compressor station, we found that the Upper Coastal Plain Research Station
(ROCK) -- an ECONet station installed and maintained b y the State Climate Office of NC -- was
the most representative for the area as it contains a near-continuous data history through 1987.
In examining the ROCK wind rose, there are two dominant wind directions: southwesterly and
northeasterly, evidenced by the spokes that extend out to and beyond the 10%+ frequency for the
30-year monitoring period.
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Figure 3.1 Wind Rose for Upper Coastal Plain Res Stn
Source: ECONet station installed and maintained by the State Climate Office of NC
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Demographic and Socioeconomic Data
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4.1 CDC Statistics for Halifax County
Source: Centers for Disease Control
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Halifax County
Source: Centers for Disease Control
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Halifax County
Source: Centers for Disease Control
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4.2 CDC Statistics for Northampton County
Source: Centers for Disease Control
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Northampton County
Source: Centers for Disease Control
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Northampton County
Source: Centers for Disease Control
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EJSCREEN
EJSCREEN is an environmental justice mapping and screening tool developed by EPA.7 Using
national publically available data, this tool is used for combining demographic and
environmental indicators in maps and reports. EJSCREEN simply provides a way to display this
information and includes a method for combining environmental and demographic indicators
into EJ indexes. EJSCREEN is NOT a detailed risk assessment. There is significant uncertainty
in the data especially when looking at small geographic areas. This tool does not provide data on
every environmental impact and demographic indicator that may be relevant to a particular
location, and data may be several years old. Key environmental and regulatory decision making
about an EJ community should not be made using these data; rather the results should be used to
highlight areas where more detailed data and information is needed. The DAQ does not
regularly use this tool; rather the division uses more robust air quality and risk assessment data to
make environmental and regulatory decisions.
Caveats
The years for which the data are available and the methods used vary across the EJ indicators.
Caveats and uncertainties apply to this screening-level information, so it is essential to
understand the limitations on appropriate interprets and applications of these indicators.
Definitions
To indicate potential exposures, EJSCREEN uses environmental indicators, not demographics.
EJSCREEN uses demographics to indicate potential susceptibility. EJSCREEN then combines
the exposure and susceptibility indicators in the form of an EJ Index.
Demographic Indicators
EJSCREEN uses demographic indicators as very general indicators of a community’s potential
susceptibility to the types of environmental exposures included in this screening tool. EPA
recommends the 80th percentile to suggest that these are areas where more investigation may be
needed regarding potential exposure or potential susceptibility.
1. Demographic Index = (% minority + % low-income) / 2
Low-Income: The number or percent of a block group’s population in households where
the household income is less than or equal to twice the federal “poverty level.” Minority:
The number or percent of individuals in a block group who list their racial status as a race
other than white alone and/or list their ethnicity as Hispanic or Latino.
EJSCREEN simply defines the demographic index as the average of the percentage of
people who are low income and the percentage of people who are minorities. The
Demographic Indexes count each indicator as adding to overall potential susceptibility of
the population in a block group, and assumes the demographic indicator have equal and
additive impacts.
7 https://www.epa.gov/ejscreen Accessed Dec 2016.
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2. Other Demographic Indicators include: Linguistically isolated populations, Populations
with less than high school education, Populations under 5 years of age, Populations over
64 years of age. These are not included in the Demographic index in number 1 above.
3. These data are compiled from the 2010 – 2014 Census American Community Survey.
4. Low income is calculated by multiplying the poverty rate by 2 times because the Centers
for Disease Control and Prevention (2010) suggests lower income is correlated to
decreased heath status.
Environmental Indicators
As defined in the EJSCREEN’s 2017 technical document, environmental indicators are direct or
indirect estimates of potential exposure or health risks, such as the NATA cancer risk estimates,
and the ozone and PM2.5 concentration estimates. These indicators are screening level proxies
only and should not be used as actual health impacts. There are other aspects of an individual’s
or a community’s environmental concerns that are less readily quantified in terms of emissions,
concentrations, or risk estimates. Ozone and PM data used in EJ Screen comes from state
certified monitoring data from EPA Air Quality System (AQS).
Ozone- The health-based threshold is based on the annual National Ambient Air Quality
Standard level of 70 ppb. The data used are from 2013 AQS. The NAAQS is the annual
fourth-highest daily maximum 8-hour concentration, averaged over 3 years.
PM2.5- The health-based threshold is based on the annual National Ambient Air Quality
Standard level of 12 μg/m3. The data used are from 2013 AQS. The NAAQS is the
annual mean, averaged over 3 years.
Values reported in the EJScreen Report are the average of the pollutant concentration for the area
of study (block or census tract). If more than one tract is selected then the tool will average the
environmental indicators over the number of tracts selected.
EJ Index
The EJ Index multiplies the Environmental Indicator by the difference in Demographic index
between the block group and the entire US which is then multiplied by the census block group
population. These values are ranked by percentile using statistical software8 and provide easy to
understand values of how a particular area is compared with a larger region or the nation. For
purpose of mapping, EJ Indexes are translated to statistical numbers of percentiles using ranked
numbers from 1 to 100.
EJ Index = (Environmental Indicator) X (Demographic Index for Block Group – Demographic Index for US) X (Census Block Group
Population)
Percentile
The percentile provides a perspective on how the selected block group or area compares to the
entire state, EPA region, or nation. For example, if a given area is at the 95th percentile
nationwide, this means that only 5 percent of the US population has a higher block group value
than the average person in the location being analyzed.
8 The percentiles and lookup tables were calculated using the statistical software called R, using code written by EPA, based on
wtd.quantile() and wtd.Ecdf() functions in the Hmisc package (http://cran.r-project.org/web/packages/Hmisc/index.html). The
scripting language R is documented here: http://cran.r-project.org
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5.1 Northampton County EJSCREEN Report (Version 2017)
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5.2 Halifax County EJSCREEN Report (Version 2017)
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National Air Toxics Assessment (NATA)
The National Air Toxics Assessment (NATA) was developed by EPA as a comprehensive
evaluation of air toxics across the U.S.9 NATA provides information about risks of cancer and
other serious health effects from breathing air toxics. Assessments are based on chronic
exposure from ambient air sources. NATA results provide answers to questions about emissions,
ambient air concentrations, exposures and risks across broad geographic areas (such as counties,
states and the Nation) at a moment in time. These assessments are based on assumptions and
methods that limit the range of questions that can be answered reliably. The results cannot be
used to identify exposures and risks for specific individuals, or even to identify exposures and
risks in small geographic regions such as a specific census block, i.e., hotspots.
The DAQ may use these data to provide insights into cancer risks for a given area, as shown for
Halifax and Northampton Counties, ranked against the nation; however a more thorough
assessment is conducted where key regulatory and environmental decisions are needed.
Caveats and Limitations
The broad NATA summary categories are point, nonpoint, onroad, nonroad, fires,
biogenics, and secondary. Some of these categories are named the same as the National
Emissions Inventory (NEI) data categories but they are not identical. For example, the NATA
nonpoint category is not the same as the NEI nonpoint category because the NEI nonpoint
category includes CMVs and locomotives, while the NATA nonpoint category does not.
Further limitations of the assessment include:
gaps in data
limitations in computer models used
default assumptions used routinely in any risk assessment
limitations in the overall design of the assessment (intended to address some questions
but not others).
variations in detail and completeness of inventories from different geographical regions
Definitions:
"N" in 1 million cancer risk - A risk level of “N”-in-1 million implies a likelihood that up to
“N” people, out of one million equally exposed people would contract cancer if exposed
continuously (24 hours per day) to the specific concentration over 70 years (an assumed
lifetime). This would be in addition to those cancer cases that would normally occur in an
unexposed population of one million people. Note that this assessment looks at lifetime cancer
risks, which should not be confused with or compared to annual cancer risk estimates. If you
would like to compare an annual cancer risk estimate with the results in this assessment, you
would need to multiply that annual estimate by a factor of 70 or alternatively divide the lifetime
risk by a factor of 70.
Secondary formation - The process by which chemicals are transformed in the air into other
chemicals. When a chemical is transformed, the original HAP no longer exists; it is replaced by
one or more chemicals. Compared to the original chemical, the newer reaction products can have
9 https://www.epa.gov/national-air-toxics-assessment Accessed Dec 2017.
State of Air Quality Surrounding the Northampton Compressor Station
February 20, 2018 53
more, less, or the same toxicity. Transformations and removal processes affect both the fate of
the chemical and its atmospheric persistence. Persistence is important because human exposure
to chemical is influenced by the length of time the chemical remains in the atmosphere. Certain
HAPs (i.e., formaldehyde, acetaldehyde, and acrolein) are formed in the atmosphere through
photochemical reactions, and these “secondary” contributions are included in NATA through the
photochemical air quality modeling platform.
Biogenic emissions – Emissions of formaldehyde, acetaldehyde and methanol from vegetation
(plants and trees) as estimated by EPA models.
Point Sources – sources that are stationary and fixed and can be located using latitude and
longitude data. These sources include large industrial facilities and electric power plants.
Airports and railyards are excluded from this category, rather are included in the Nonroad
category.
Nonpoint Sources – sources which individually are too small in magnitude or too numerous to
inventory as individual point sources. Modeling excludes emissions from locomotives,
commercial marine vessels, biogenic and agricultural fires.
Onroad sources – sources include car, truck and bus emissions as estimated by EPA models.
Nonroad sources – sources include lawn and garden equipment, and construction and
recreational equipment emissions as estimated by EPA models. This category includes
commercial marine vessels, locomotives and aircraft engine emissions associated with landing
and take-off, and airport ground support vehicles.
Fires – sources include wildfire, prescribed burning, and agricultural burning emissions as
estimated by EPA models.
Background concentrations - The contributions to outdoor air toxics concentrations resulting
from natural sources, persistence in the environment of past years' emissions, and long-range
transport from distant sources. The vast majority of risk from the NATA background
concentrations is from carbon tetrachloride, a ubiquitous pollutant that has few sources of
emissions but is persistent due to its long half-life. Background sources, also included in NATA,
can include natural sources and anthropogenic air toxics emitted in prior years that persist in the
environment, or air toxics emitted from distant sources, including (for those HAPs modeled in
HEM-3 but not the Community Multiscale Air Quality [CMAQ]) air toxics transported farther
than 50 kilometers.
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6.1 National Air Toxics Assessment (NATA) for Halifax and Northampton
County (Source: EPA Draft)
Figure 6.1 Halifax County Cancer Risk, 2014NATA*
Data Source – 2014v1 National Emissions Inventory, EPA
Figure 6.2 Northampton County Cancer Risk, 2014NATA*
Data Source – 2014v1 National Emissions Inventory, EPA
Point
10%
OnRoad
7%
NonRoad
2%
NonPoint
8%
Fires
2%
Biogenics
15%
Secondary
56%
Background
0%
Point
11%
OnRoad
5%
NonRoad
2%
NonPoint
7%
Fires
2%
Biogenics
16%
Secondary
57%
Background
0%
Total Cancer Risk = 31.84 in 1 million
Entire State Cancer Risk = 34.05 in 1 million
County Ranking = 42 of 100 highest cancer risk
Total Cancer Risk = 30.37 in 1 million
Entire State Cancer Risk = 34.05 in 1 million
County Ranking = 53 of 100 highest cancer risk
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Table 6.1 Air Toxic Pollutants Included in NATA
Air Toxic (Clean Air Act Name)
NEI
Pollutant
Code (CAS
Number)a Notes
1,1,2,2-Tetrachloroethane 79345
1,1,2-Trichloroethane 79005
1,1-Dimethyl hydrazine 57147
1,2,4-Trichlorobenzene 120821
1,2-Dibromo-3-chloropropane 96128
1,2-Diphenylhydrazine 122667 Not in NATA because there were no emissions
1,2-Epoxybutane 106887
1,2-Propylenimine (2-methyl aziridine) 75558
1,3-Butadiene 106990
1,3-Dichloropropene 542756
1,3-Propane sultone 1120714
1,4-Dichlorobenzene(p) 106467
1,4-Dioxane 123911
2,2,4-Trimethylpentane 540841
2,4,5-Trichlorophenol 95954
2,4,6-Trichlorophenol 88062
2,4-D, salts and esters 94757
2,4-Dinitrophenol 51285
2,4-Dinitrotoluene 121142
2,4-Toluene diamine 95807
2,4-Toluene diisocyanate 584849
2- Acetylaminofluorene 53963
2-Chloroacetophenone 532274
2-Nitropropane 79469
3,3'-Dichlorobenzidine 91941
3,3'-Dimethoxybenzidine 119904
3,3'-Dimethylbenzidine 119937
4,4'-Methylene bis(2-chloroaniline) 101144
4,4'-Methylenedianiline 101779
4,6-Dinitro-o-cresol, and salts 534521
4-Aminobiphenyl 92671
4-Nitrobiphenyl 92933
4-Nitrophenol 100027
Acetaldehyde 75070
Acetamide 60355
Acetonitrile 75058
Acetophenone 98862
Acrolein 107028
Acrylamide 79061
Acrylic acid 79107
Acrylonitrile 107131
Allyl chloride 107051
Aniline 62533
Antimony Compounds 7440360
Arsenic Compounds (inorganic
including arsine)
7440382
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Air Toxic (Clean Air Act Name)
NEI
Pollutant
Code (CAS
Number)a Notes
Benzene (including benzene from
gasoline)
71432
Benzidine 92875
Benzotrichloride 98077
Benzyl chloride 100447
Beryllium Compounds 7440417
Beta-Propiolactone 57578 Not in NATA because there were no emissions
Biphenyl 92524
Bis(2-ethylhexyl)phthalate (DEHP) 117817
Bis(chloromethyl)ether 542881
Bromoform 75252
Cadmium Compounds 7440439
Calcium cyanamide 156627
Captan 133062
Carbaryl 63252
Carbon disulfide 75150
Carbon tetrachloride 56235
Carbonyl sulfide 463581
Catechol 120809
Chloramben 133904 Not in NATA because there were no emissions
Chlordane 57749
Chlorine 7782505
Chloroacetic acid 79118
Chlorobenzene 108907
Chlorobenzilate 510156
Chloroform 67663
Chloromethyl methyl ether 107302
Chloroprene 126998
Chromium Compounds multiple NATA includes only hexavalent chromium
Cobalt Compounds 7440484
Coke Oven Emissions 140
Cresols/Cresylic acid (isomers and
mixture)
1319773 Modeled as cresols
Cumene 98828
Cyanide Compounds multiple
Diazomethane 334883
Dibenzofurans 132649
Dibutylphthalate 84742
Dichloroethyl ether (Bis(2-
chloroethyl)ether)
111444
Dichlorvos 62737
Diethanolamine 111422
Diethyl sulfate 64675
Dimethyl aminoazobenzene 60117
Dimethyl carbamoyl chloride 79447
Dimethyl formamide 68122
Dimethyl phthalate 131113
Dimethyl sulfate 77781
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Air Toxic (Clean Air Act Name)
NEI
Pollutant
Code (CAS
Number)a Notes
Epichlorohydrin
(l-Chloro-2,3-epoxypropane)
106898
Ethyl acrylate 140885
Ethyl benzene 100414
Ethyl carbamate (Urethane) 51796
Ethyl chloride (Chloroethane) 75003
Ethylene dibromide (Dibromoethane) 106934
Ethylene dichloride (1,2-
Dichloroethane)
107062
Ethylene glycol 107211
Ethylene imine (Aziridine) 151564
Ethylene oxide 75218
Ethylene thiourea 96457
Ethylidene dichloride (1,1-
Dichloroethane)
75343
Formaldehyde 50000
Glycol Ethers N/A
Heptachlor 76448
Hexachlorobenzene 118741
Hexachlorobutadiene 87683
Hexachlorocyclopentadiene 77474
Hexachloroethane 67721
Hexamethylene- 1,6-diisocyanate 822060
Hexamethylphosphoramide 680319 Not in NATA because there were no emissions
Hexane 110543
Hydrazine 302012
Hydrochloric acid 7647010
Hydrogen fluoride (Hydrofluoric acid) 7664393
Hydroquinone 123319
Isophorone 78591
Lead Compounds 7439921
Lindane (all isomers) 58899
Maleic anhydride 108316
Manganese Compounds 7439965
m-Cresol m 108394
Mercury Compounds 7439976
Methanol 67561
Methoxychlor 72435
Methyl bromide (Bromomethane) 74839
Methyl chloride (Chloromethane) 74873
Methyl chloroform (1,1,1-
Trichloroethane)
71556
Methyl hydrazine 60344
Methyl iodide (Iodomethane) 74884
Methyl isobutyl ketone (Hexone) 108101
Methyl isocyanate 624839
Methyl methacrylate 80626
Methyl tert butyl ether 1634044
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Air Toxic (Clean Air Act Name)
NEI
Pollutant
Code (CAS
Number)a Notes
Methylene chloride (Dichloromethane) 75092
Methylene diphenyl diisocyanate (MDI) 101688
m-Xylenes 108383 Modeled as xylenes
N,N-Dimethylaniline 121697
Naphthalene 91203
Nickel Compounds 7440020
Nitrobenzene 98953
N-Nitrosodimethylamine 62759
N-Nitrosomorpholine 59892
N-Nitroso-N-Methylurea 684935 Not in NATA because there were no emissions
o-Anisidine 90040
o-Cresol 95487 Modeled as cresols
o-Toluidine 95534
o-Xylenes 95476 Modeled as xylenes
Parathion 56382 Not in NATA because there were no emissions
p-Cresol 106445 Modeled as cresols
Pentachloronitrobenzene
(Quintobenzene)
82688
Pentachlorophenol 87865
Phenol 108952
Phosgene 75445
Phosphine 7803512
Phosphorus 7723140
Phthalic anhydride 85449
Polychlorinated biphenyls (Aroclors) 1336363
Polycyclic Organic Matter N/A About 50 specific compounds are in the NEI.
They were modeled as 9 discrete PAH groups
representing different upper-bound risk estimate
“bins“ since specific compounds have a wide
range of upper-bound risk estimates.
p-Phenylenediamine 106503
Propionaldehyde 123386
Propoxur (Baygon) 114261
Propylene dichloride (1,2-
Dichloropropane)
78875
Propylene oxide 75569
p-Xylenes 106423 Modeled as xylenes
Quinoline 91225
Quinone 106514
Selenium Compounds 7782492
Styrene 100425
Styrene oxide 96093
Tetrachloroethylene (Perchloroethylene) 127184
Titanium tetrachloride 7550450
Toluene 108883
Toxaphene (chlorinated camphene) 8001352
Trichloroethylene 79016
Triethylamine 121448
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Air Toxic (Clean Air Act Name)
NEI
Pollutant
Code (CAS
Number)a Notes
Trifluralin 1582098
Vinyl acetate 108054
Vinyl bromide 593602
Vinyl chloride 75014
Vinylidene chloride (1,1-
Dichloroethylene)
75354
Xylenes (isomers and mixture) 1330207 Modeled as xylenes
Diesel PM Diesel PM is not a HAP and not on the Clean Air
Act list but it is modeled in NATA for Nonroad
sources
a In most cases, the NEI pollutant code is the same as the CAS number. In a few cases (e.g., coke oven
emissions) a CAS number has not been assigned, and NEI uses a unique pollutant code.
Table 6.2 Pollutants Excluded from NATA
Air Toxic (Clean Air Act Name)
NEI Pollutant
Code (CAS
Number)a Exclusion reason
2,3,7,8-Tetrachlorodibenzo-p- dioxin 1746016 Not included in NATA due to uncertainty in reporting
to NEI and exposure route for dioxins is ingestion
Other dioxins/furans multiple
Radionuclides Not included in NATA due to uncertainty in reporting
to NEI and emissions not compatible with NATA
modeling
Dichlorodiphenyldichloroethylene (DDE) 72559
incorrectly
referred to in
the Section
112(b) list as
3547-04-4
Compound not reported to NEI
Fine mineral fibers (including rockwool and
slag wool and fine mineral fibers)
Fine mineral
fibers: 383
Rockwool:617
Slagwool:616
Not in NATA because there were no emissions
Asbestos 1332214 Inhalation exposures not typically expressed in mass
units
Diazomethane 334883 Not in NATA because there were no emissions
Hexamethylphosphoramide 680319 Not in NATA because there were no emissions
a In most cases, the NEI pollutant code is the same as the CAS number. In a few cases (e.g., coke oven emissions) a CAS
number has not been assigned, and NEI uses a unique pollutant code.