AQ_AM_20230628_BP_AnnPln_Final 2023-2024 Volume 2-D Raleigh Region_Final

2023-2024 Annual Monitoring Network
Plan for the North Carolina Division of Air
Quality
Volume 2
Site Descriptions by Division of Air Quality Regional Office
and Metropolitan Statistical Area
D. The Raleigh Monitoring Region

June 28, 2023

D-2

Table of Contents
List of Figures ............................................................................................................................................... 2
D. The Raleigh Monitoring Region ............................................................................................................ 5
(1) Durham-Chapel Hill MSA ...................................................................................................................... 5
(2) The Northeastern Piedmont .............................................................................................................. 13
(3) The Raleigh MSA ................................................................................................................................ 15
(4) Rocky Mount MSA .............................................................................................................................. 24
(5) The Wilson Micropolitan Statistical Area ........................................................................................... 27
(6) The Sanford Micropolitan Statistical Area .......................................................................................... 29
Appendix D.1 Annual Network Site Review Forms for 2022 .................................................................... 32

List of Figures
Figure D1. The Raleigh monitoring region .................................................................................................... 5
Figure D2. Location of monitors in the Durham-Chapel Hill MSA. ............................................................... 5
Figure D3. The Durham Armory ozone, sulfur dioxide and particle-monitoring site ................................... 6
Figure D4. Looking north from the Durham Armory site .............................................................................. 6
Figure D5. Durham Armory site looking northeast ....................................................................................... 6
Figure D6. Durham Armory site looking northwest ...................................................................................... 7
Figure D7. Looking west from the Durham Armory site ............................................................................... 7
Figure D8. Durham Armory site looking southwest ...................................................................................... 7
Figure D9. Looking east from the Durham Armory site ................................................................................ 7
Figure D10. Durham Armory site looking southeast ..................................................................................... 7
Figure D11 Durham Armory site looking south ............................................................................................ 7
Figure D12. The Butner ozone-monitoring site ............................................................................................ 7
Figure D13. Looking north from the Butner site ........................................................................................... 8
Figure D14. Looking northwest from the Butner site ................................................................................... 8
Figure D15. Looking west from the Butner site ............................................................................................ 8
Figure D16. Looking northeast from the Butner site .................................................................................... 8
Figure D17. Looking east from the Butner site ............................................................................................. 8
Figure D18. Looking southeast from the Butner site .................................................................................... 8
Figure D19. Looking southwest from the Butner site ................................................................................... 9
Figure D20. Looking south from the Butner site ........................................................................................... 9
Figure D21. Bushy Fork ozone monitoring site ............................................................................................. 9
Figure D22. Bushy Fork site looking north .................................................................................................... 9
Figure D23. Bushy Fork site looking west ..................................................................................................... 9
Figure D24. Bushy Fork site looking east ...................................................................................................... 9
Figure D25. Bushy Fork site looking south .................................................................................................... 9
D-3

Figure D26. Location of Durham-Chapel Hill PWEI monitor in relationship to centers of population in
2020 ............................................................................................................................................................ 11
Figure D27. Location of the Durham-Chapel Hill PWEI sulfur dioxide monitor, red dot, in relationship to
sulfur dioxide sources ................................................................................................................................. 12
Figure D28. Location of the Armory monitoring site, A, in relationship to Carolina Sunrock, B ............. 12
Figure D29. Location of the Northampton County monitoring site. The purple circle is the Northampton
County nitrogen dioxide and fine particle monitoring site. ........................................................................ 13
Figure D30. The Northampton fine particle and nitrogen dioxide-monitoring site ................................... 13
Figure D31. Looking north from the Northampton site .............................................................................. 14
Figure D32. Looking west from the Northampton site ............................................................................... 14
Figure D33. Looking east from the Northampton site ................................................................................ 14
Figure D34. Looking south from the Northampton site ............................................................................. 14
Figure D35. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the northeastern
Piedmont ..................................................................................................................................................... 14
Figure D36. Monitoring sites located in the Raleigh MSA. ......................................................................... 15
Figure D37. The West Johnston ozone and fine-particle monitoring site .................................................. 16
Figure D38. Looking north from the West Johnston site ............................................................................ 16
Figure D39. Looking east from the West Johnston site .............................................................................. 16
Figure D40. Looking west from the West Johnston site ............................................................................. 17
Figure D41. Looking south from the West Johnston site ............................................................................ 17
Figure D42. Millbrook NCore monitoring site ............................................................................................. 18
Figure D43. Looking north from the Millbrook site .................................................................................... 18
Figure D44. Looking northwest from the Millbrook site ............................................................................ 18
Figure D45. Looking northeast from the Millbrook site ............................................................................. 19
Figure D46. Looking east from the Millbrook site ...................................................................................... 19
Figure D47. Looking west from the Millbrook site...................................................................................... 19
Figure D48. Looking southwest from the Millbrook site ............................................................................ 19
Figure D49. Looking southeast from the Millbrook site ............................................................................. 19
Figure D50. Looking south from the Millbrook site .................................................................................... 19
Figure D51. Proposed location of sensor collocation shelter looking south from the monitoring buildings
.................................................................................................................................................................... 20
Figure D52. The Triple Oak near road nitrogen dioxide monitoring site, 37-183-0021 ............................. 21
Figure D53. Looking north from the Triple Oak site ................................................................................... 21
Figure D54. Looking northeast from the Triple Oak site ............................................................................. 21
Figure D55. Looking northwest from the Triple Oak site ............................................................................ 22
Figure D56. Looking west from the Triple Oak site ..................................................................................... 22
Figure D57. Looking southwest from the Triple Oak site ........................................................................... 22
Figure D58. Looking east from the Triple Oak site ...................................................................................... 22
Figure D59. Looking southeast from the Triple Oak site ............................................................................ 22
Figure D60. Looking south from the Triple Oak site ................................................................................... 22
Figure D61. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the Raleigh MSA ......... 24
Figure D62. Monitoring site location in the Rocky Mount MSA ................................................................. 24
D-4

Figure D63. Leggett seasonal ozone and air quality index fine particle monitoring site ............................ 25
Figure D64. Looking north from the Leggett site ........................................................................................ 25
Figure D65. Looking northwest from the Leggett site ................................................................................ 25
Figure D66. Looking northeast from the Leggett site ................................................................................. 25
Figure D67. Looking east from the Leggett site .......................................................................................... 25
Figure D68. Looking west from the Leggett site ......................................................................................... 26
Figure D69. Looking southwest from the Leggett site ................................................................................ 26
Figure D70. Looking southeast from the Leggett site ................................................................................. 26
Figure D71. Looking south from the Leggett site ........................................................................................ 26
Figure D72. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the Rocky Mount MSA 26
Figure D73. Wilson County Population Projections .................................................................................... 27
Figure D74. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the Wilson MiSA ......... 28
Figure D75. Location of the former monitoring site in the Sanford MiSA .................................................. 30
Figure D76. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the Sanford MiSA ........ 30

D-5

D. The Raleigh Monitoring Region
The Raleigh monitoring region of North
Carolina, shown in Figure D1, consists of six
sections. (1) The Durham-Chapel Hill
metropolitan statistical area, or MSA, consists
of Chatham, Durham, Granville, Orange and
Person counties; (2) the northeastern Piedmont
consists of Halifax, Northampton, Vance and
Warren counties; (3) the Raleigh MSA consists
of Franklin, Johnston and Wake counties; (4) the
Rocky Mount MSA consists of Edgecombe and
Nash counties; (5) the Wilson micropolitan
statistical area (MiSA) consists of Wilson
County; and (6) the Sanford MiSA consists of
Lee County.
Figure D1. The Raleigh monitoring region
The dots show the approximate locations of
most of the monitoring sites in this region
.
(1) Durham-Chapel Hill MSA
The Durham-Chapel Hill MSA consists of
five counties: Chatham, Durham,
Granville, Orange and Person. The
major metropolitan areas are the cities
of Durham and Chapel Hill. The North
Carolina Division of Air Quality, or DAQ,
currently operates three monitoring
sites in the Durham-Chapel Hill MSA.
These sites are located at the Durham
Armory in the City of Durham in
Durham County, Butner in Granville
County, and Bushy Fork in Person
County. Figure D2 maps the locations of
these monitors. From Jan. 1, 2017,
through Dec. 31, 2020, DAQ in
cooperation with Duke Energy Progress
operated a sulfur dioxide monitor in
Semora (Person County) as part of the
data requirements rule. DAQ shut down
the seasonal ozone monitor in Pittsboro
in Chatham County on Oct. 31, 2015, at
the end of ozone season and shut down
the rotating sulfur dioxide monitor on
Feb. 4, 2015.

Figure D2. Location of monitors in the Durham-Chapel Hill MSA.
D-6

At the Durham Armory site, DAQ operates a seasonal ozone monitor; a population weighted emission
index, or PWEI, sulfur dioxide monitor; a continuous low volume PM10 monitor; and a continuous fine
particle monitor. Figure D3 through Figure D11 presents pictures of the site, as well as views looking
north, northeast, east, southeast, south, southwest, west and northwest. This fine-particle monitoring
site is the design value site for the MSA. On Jan. 1, 2011, DAQ started operating a low volume PM10
monitor at the site to meet minimum PM10 monitoring requirements in the Durham-Chapel Hill MSA and
to provide PM10-2.5 data. In May 2015, the division changed this monitor to a continuous low volume
PM10 monitor. On Aug. 14, 2019, DAQ added a collocated one-in-six-day fine particle FRM monitor. The
division shut down the one-in-three-day and one-in-six-day fine particle FRM monitors on Sep. 30, 2020,
and made the continuous fine particle monitor at the site the primary monitor.
Figure D3. The Durham Armory ozone, sulfur dioxide and particle-monitoring site
Figure D4. Looking north from the Durham Armory site
Figure D5. Durham Armory site looking northeast
D-7

Figure D6. Durham Armory site looking northwest
Figure D7. Looking west from the Durham Armory site
Figure D8. Durham Armory site looking southwest
Figure D9. Looking east from the Durham Armory site
Figure D10. Durham Armory site looking southeast
Figure D11 Durham Armory site looking south

At the Butner site, 37-077-0001, DAQ operates a
seasonal ozone monitor. Figure D12 through Figure
D20 provide views of the site as well as looking
north, northeast, east, southeast, south,
southwest, west and northwest. The division
established the Butner site as the downwind site
for the Durham-Chapel Hill MSA when the wind is
from the primary direction during the season of
highest ozone concentrations. In 2023, DAQ will
replace the shelter, if funding becomes available
and may relocate the site at that time. Figure D12. The Butner ozone-monitoring site
D-8

Figure D13. Looking north from the Butner site
Figure D14. Looking northwest from the Butner site
Figure D15. Looking west from the Butner site
Figure D16. Looking northeast from the Butner site
Figure D17. Looking east from the Butner site
Figure D18. Looking southeast from the Butner site
D-9

Figure D19. Looking southwest from the Butner site Figure D20. Looking south from the Butner site
At the Bushy Fork site, DAQ operates a seasonal
ozone monitor. A special purpose sulfur dioxide
monitor operated for 12 months from June
2014 through May 2015 to provide background
sulfur dioxide concentrations to support
modeling requirements for the sulfur dioxide
national ambient air quality standard, or
NAAQS. Figure D21 through Figure D25 show a
picture of the site as well as views looking
north, east, south and west. Figure D21. Bushy Fork ozone monitoring site
Figure D22. Bushy Fork site looking north
Figure D23. Bushy Fork site looking west
Figure D24. Bushy Fork site looking east
Figure D25. Bushy Fork site looking south

D-10

At the beginning of the 2018 ozone season, DAQ noted that construction on an access road had begun.
As the season progressed, the property owner placed a paved road within about 6 meters of the site
shelter. Ultimately, the property owner paved the road with asphalt. The road provides access to a cell
tower recently placed at the park. Sometime in the future, the division may shut down this monitoring
site because it is no longer required by 40 CFR Part 58, Appendix D.
In 2008, the United States Environmental Protection Agency, or EPA, expanded the lead monitoring
network to support the lower lead NAAQS of 0.15 micrograms per cubic meter.1 On Dec. 27, 2010, the
EPA revised the monitoring requirements to focus on fence-line monitoring located at facilities that emit
0.5 tons or more of lead per year and at National Core, NCore, monitoring sites.2 On March 28, 2016,
the EPA finalized changes to ambient monitoring quality assurance and other requirements, which
removed the requirement for lead monitoring at NCore monitoring stations in urban areas with
populations greater than 500,000.3 These changes to the lead monitoring network requirements did not
require any lead monitoring in the Durham-Chapel Hill MSA. The Duke Energy Progress Roxboro
electricity-generating facility emitted 60 pounds of lead in 2020 and CPI USA North Carolina, LLC,
emitted 141 pounds,4 both well below the 0.5-ton threshold. In addition, modeling performed in 2009
indicated the concentrations of lead in ambient air around the Duke Progress Energy Roxboro electricity
generating facility are less than 0.01 micrograms per cubic meter, which is far enough below the NAAQS
that no fence-line monitoring is required for this facility. CPI USA North Carolina, LLC, ceased operations
on March 31, 2021.
Currently, the MSA is required to operate two ozone monitors – one at Bushy Fork, 37-145-0003 (57 ppb
design value), and one at the Durham Armory, 37-063-0015 (58 ppb design value). Beginning in 2017,
seasonal ozone monitoring started on March 1 instead of April 1. The 2010 nitrogen dioxide monitoring
requirements,5 as modified in 2016,6 do not require the Durham-Chapel Hill MSA to monitor for
nitrogen dioxide.
The 2010 sulfur dioxide monitoring requirements added additional monitoring in this MSA. Because of
power-generating facilities in Person and Chatham counties and a large population base, DAQ added a
PWEI population exposure monitor at the Armory site on Jan. 1, 2013. Figure D26 shows the location of
the PWEI monitor relative to where people lived based on the 2020 census. Figure D27 shows the

1 National Ambient Air Quality Standards for Lead, Federal Register, Vol. 73, No. 219, \ Wednesday, Nov. 12, 2008,
p. 66964, available on the worldwide web at https://www.gpo.gov/fdsys/pkg/FR-2008-11-12/pdf/E8-25654.pdf.
2 Revisions to Lead Ambient Air Monitoring Requirements, Federal Register, Vol. 75, No. 247, Monday, Dec. 27,
2010, p. 81126, available on the worldwide web at https://www.gpo.gov/fdsys/pkg/FR-2010-12-27/pdf/2010-
32153.pdf#page=1.
3 Revisions to Ambient Monitoring Quality Assurance and Other Requirements, Federal Register, Vol. 81, No. 59,
Monday, March 28, 2016, p. 17248, available on the worldwide web at https://www.gpo.gov/fdsys/pkg/FR-2016-
03-28/pdf/2016-06226.pdf.
4 Data obtained from the 2020 EPA Toxics Release Inventory Tracker available at
https://edap.epa.gov/public/extensions/TRIToxicsTracker/TRIToxicsTracker.html#..
5 Primary National Ambient Air Quality Standards for Nitrogen Dioxide, Federal Register, Vol. 75, No. 26, Feb. 9,
2010, available on the worldwide web at https://www3.epa.gov/ttn/naaqs/standards/nox/fr/20100209.pdf.
6 Revision to the Near-road NO2 Minimum Monitoring Requirements, Federal Register, Vol. 81, No. 251, Dec. 30,
2016, available on the worldwide web at https://www.gpo.gov/fdsys/pkg/FR-2016-12-30/pdf/2016-31645.pdf.

D-11

distribution of sulfur dioxide emissions among the counties in the MSA. The closest permitted source of
sulfur dioxide to the Armory site is Carolina Sunrock, located 3.25 kilometers southeast of the site, as
shown in Figure D28. Carolina Sunrock reported emitting 2.7 tons of sulfur dioxide in 2016.7 As part of
the Data Requirements Rule, Duke and DAQ added a source-oriented sulfur dioxide monitor in this MSA
at Semora in Person County on Jan. 1, 2017. This monitor operated until Dec. 31, 2020.

Figure D26. Location of Durham-Chapel Hill PWEI monitor in relationship to centers of population in 2020
(The Durham Armory site is located at the black circle; population data is from the U.S. Census Bureau)

7 North Carolina Criteria and Toxic Air Pollutant Point Source Emissions Report, available on the worldwide web at
https://xapps.ncdenr.org/aq/ToxicsReport/ToxicsReportFacility.jsp?ibeam=true&county_code=063&year=2016&s
orting=3&overridetype=All&pollutant=264, accessed April 20, 2018.

D-12

Figure D27. Location of the Durham-Chapel Hill PWEI sulfur dioxide monitor, red dot, in relationship to sulfur dioxide
sources

Figure D28. Location of the Armory monitoring site, A, in relationship to Carolina Sunrock, B

D-13

Changes to the carbon monoxide monitoring requirements did not add additional monitoring to this
MSA because the population is less than 1,000,000.
(2) The Northeastern Piedmont
The northeastern Piedmont consists of four counties: Halifax, Northampton, Vance and Warren. There is
not an MSA in these counties; however, Henderson MiSA is in Vance County and the Roanoke Rapids
MiSA consists of Halifax and Northampton counties. DAQ currently operates one monitoring site in the
northeastern Piedmont. This site is located in Northampton County. Figure D29 provides the location of
this monitoring site.
Figure D29. Location of the Northampton County monitoring site. The purple circle is the Northampton County nitrogen
dioxide and fine particle monitoring site.
At the Northampton County site, 37-131-0001, DAQ operates special purpose fine particle and nitrogen
dioxide monitors. Figure D30 through Figure D34 provide pictures of the site as well as the views looking
north, east, south and west. DAQ established the Northampton County site as a background site for the
Roanoke Rapids MiSA.
Figure D30. The Northampton fine particle and nitrogen dioxide-monitoring site

D-14

Figure D31. Looking north from the Northampton site
Figure D32. Looking west from the Northampton site
Figure D33. Looking east from the Northampton site
Figure D34. Looking south from the Northampton site
This area was not required to add any lead monitors because of the 2010 changes made to the lead
monitoring requirements. As shown in Figure D35, no facilities here emit 0.5 ton or more of lead per
year.8

Figure D35. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the northeastern Piedmont

8 Data obtained from the 2020 EPA Toxics Release Inventory Tracker available at
https://edap.epa.gov/public/extensions/TRIToxicsTracker/TRIToxicsTracker.html#.

D-15

The 2015 ozone monitoring requirements did not require additional monitoring in the northeastern
Piedmont. The area does not have any MSAs that 40 Code of Federal Regulations, or CFR, Part 58,
Appendix D requires to conduct population exposure monitoring in urban areas. The northeastern
Piedmont did not add monitors to comply with the 2010 nitrogen dioxide monitoring requirements
because it does not have any roads exceeding the traffic threshold and does not have any MSAs that
trigger nitrogen dioxide monitoring requirements. The northeastern Piedmont also did not add sulfur
dioxide monitors to comply with the 2010 sulfur dioxide monitoring requirements because there are no
large sources of sulfur dioxide in this area. This area also does not need to do carbon monoxide
monitoring to comply with the changes to the carbon monoxide monitoring requirements because the
population is under 1,000,000.
(3) The Raleigh MSA
As shown in Figure D36, the Raleigh MSA consists of three counties: Franklin, Johnston and Wake. The
major metropolitan areas include Raleigh and Cary. DAQ currently operates three monitoring sites in the
Raleigh MSA. These sites are located at West Johnston in Johnston County and Millbrook and Triple Oak
in Wake County. The division shut down the ozone monitors at Franklinton and Fuquay on Oct. 31, 2015.
Figure D36. Monitoring sites located in the Raleigh MSA.
At the West Johnston site, 37-101-0002, DAQ operates a seasonal ozone monitor and a continuous fine
particle monitor. The division established the West Johnston ozone site as the upwind site for the
Millbrook multipollutant site, center, neighborhood scale; Triple Oak near-road site, furthest west, micro
scale; and West Johnston ozone and particle monitors, furthest east, urban scale.

D-16

Raleigh MSA when the wind is from the secondary direction during the season of highest ozone
concentrations. This site is one of two ozone-monitoring sites in the MSA. Title 40 CFR Part 58, Appendix
D requires the Raleigh MSA to have two ozone monitoring sites. The West Johnston fine particle site is
the third fine-particle monitoring site in the MSA. The Raleigh MSA has a population over 1,000,000
people and is currently required, based on its design value, to have two fine particle monitors. DAQ
added a continuous fine particle monitor at the site in 2016 that replaced the FRM monitor at the end of
2017. Figure D37 through Figure D41 provide a picture of the site and views looking north, east, south
and west.
Figure D37. The West Johnston ozone and fine-particle monitoring site
Figure D38. Looking north from the West Johnston site Figure D39. Looking east from the West Johnston site

D-17

Figure D40. Looking west from the West Johnston site Figure D41. Looking south from the West Johnston site
At the Millbrook site, 37-183-0014, DAQ operates year-round ozone, one-in-three-day fine particle FRM,
one-in-three-day manual SASS and URG fine particle speciation, continuous BAM fine particle,
continuous PM10 and PM10-2.5, nitrogen dioxide and trace-level sulfur dioxide, carbon monoxide and
reactive oxide of nitrogen monitors. The manual one-in-three-day PM10 and PM10-2.5 monitors, as well as
the collocated one-in-six-day PM10 monitor, ended in 2017 after DAQ installed a continuous PM10 and
PM10-2.5 monitor at the site. DAQ also started evaluating a Teledyne T640X PM10-2.5 monitor at Millbrook
in April 2017 and made this monitor the primary fine particle, PM10 and PM10-2.5 monitor on Oct. 1, 2020.
The division shut down the BAM fine particle, PM10 and PM10-2.5 monitors on July 1, 2021. DAQ also
operates a meteorological station at this site. The division shut down the continuous fine particle
monitors for sulfate, nitrate and black carbon on March 31, 2020, to make space for the PAMS monitors.
PAMS monitoring 8-hour carbonyls, and hourly mixing layer height, barometric pressure and ultraviolet
radiation began on June 1, 2021. Monitoring for hourly speciated VOCs did not start in 2021 due to
instrument contamination problems which DAQ is still working to resolve. Also, on May 17, 2021, the
division replaced the photolytic NO2 monitor with a CAPS NO2 monitor. Figure D42 through Figure D50
provide a picture of the site as well as views looking north, northeast, east, southeast, south, southwest,
west and northwest.
The Millbrook site is an NCore, National Community Representative, site so DAQ installed the probe for
the reactive oxide of nitrogen monitor at this site on a 10-meter tower in late 2010. On Jan. 26, 2022,
the tower on which the probe is installed broke a cable that allows the tower to be raised and lowered.
DAQ is currently working on getting the tower repaired. On Dec. 27, 2011, DAQ began analyzing the low
volume PM10 filters for lead on a one-in-six-day schedule to meet the 2010 monitoring requirements for
lead monitoring at NCore sites. This lead monitoring ended on April 30, 2016. In 2013, the division
added a carbonyl sampler to the site to support a shale-gas development background-monitoring study
in Lee County. DAQ has monitored for VOCs at Millbrook since July 14, 2004, on a one-in-six-day
schedule. Currently, DAQ has been forced to suspend the VOC portion of the UAT program due to
staffing issues at the Reedy Creek Analysis Laboratory. This suspension of the VOC program began in
February of 2023 and is expected to continue for the remainder of the year. DAQ hopes to reestablish
the program in 2024 when staffing and training issues are resolved. DAQ continues to operate the UAT

D-18

Aldehydes program. On April 24, 2018, the division added a background rainwater-collection sampler to
the site. In 2022, DAQ will add a sensor collocation shelter to the site as shown in Figure D51. The
shelter will be located on a 6-foot by 6-foot concrete pad approximately 2 meters to the east of the
particle monitoring platform.
Figure D42. Millbrook NCore monitoring site
Figure D43. Looking north from the Millbrook site Figure D44. Looking northwest from the Millbrook site

D-19

Figure D45. Looking northeast from the Millbrook site
Figure D46. Looking east from the Millbrook site
Figure D47. Looking west from the Millbrook site
Figure D48. Looking southwest from the Millbrook site
Figure D49. Looking southeast from the Millbrook site
Figure D50. Looking south from the Millbrook site

D-20

Figure D51. Proposed location of sensor collocation shelter looking south from the monitoring buildings
At the Triple Oak site, 37-183-0021, DAQ operates a near-road nitrogen dioxide monitor with a
photolytic convertor, trace-level carbon monoxide and continuous fine particle monitors. The nitrogen
dioxide monitor started operating on Jan. 8, 2014. The carbon monoxide monitor started operating on
Dec. 6, 2016, and the fine particle monitor started operating in 2017. Figure D52 through Figure D60
provide a picture of the site as well as views looking north, northeast, east, southeast, south, southwest,
west and northwest.

D-21

Figure D52. The Triple Oak near road nitrogen dioxide monitoring site, 37-183-0021
Figure D53. Looking north from the Triple Oak site Figure D54. Looking northeast from the Triple Oak site

D-22

Figure D55. Looking northwest from the Triple Oak site
Figure D56. Looking west from the Triple Oak site

Figure D57. Looking southwest from the Triple Oak site
Figure D58. Looking east from the Triple Oak site
Figure D59. Looking southeast from the Triple Oak site
Figure D60. Looking south from the Triple Oak site
Due to the 2010 nitrogen dioxide monitoring requirements, DAQ added two nitrogen dioxide monitors
to the Raleigh MSA. Because its population exceeds the 1,000,000-threshold, it was required to have a
near-road monitor starting Jan. 1, 2014. DAQ placed the near-road monitoring station on the westbound
side of I-40 between Exit 283 and 284. The EPA approved this location in 2012. The Raleigh MSA has
over 1,000,000 people so it is also required to have a community or area-wide monitor. This monitor is
located at the Raleigh Millbrook NCore monitoring site. The regulations required this monitor to start

D-23

operating on Jan. 1, 2013. DAQ asked for permission to delay installing the monitor so that the division
could install a photolytic nitrogen dioxide monitor at the site. The photolytic nitrogen dioxide monitor is
more selective for nitrogen dioxide but because EPA approved it as an equivalent method in 2012, DAQ
could not purchase it and have it up and operational by the Jan. 1, 2013, scheduled start date. DAQ
began monitoring for nitrogen dioxide at Millbrook on Dec. 10, 2013.
This MSA was also required to add a carbon monoxide monitor to comply with the changes to the
carbon monoxide monitoring requirements. Starting Jan. 1, 2017, the regulation requires near-road,
carbon monoxide monitoring in MSAs with populations greater than one million. On Jan. 1, 2017, DAQ
was also required to add a fine particle monitor at the Triple Oak near-road monitoring site.
Changes to the ozone monitoring requirements in 2015 did not require additional ozone monitoring in
the Raleigh MSA. The MSA currently meets the minimum number of monitors required by 40 CFR Part
58, Appendix D for population exposure monitoring in urban areas. Seasonal ozone monitoring starts on
March 1 instead of April 1 starting in 2017. The 2015 ozone monitoring regulations did require the
division to begin PAMS monitoring at the Millbrook NCore site starting on June 1, 2021.
The 2010 sulfur dioxide monitoring requirements did not require additional sulfur dioxide monitors in
the Raleigh MSA because there are no large sources of sulfur dioxide in the MSA. To comply with the
December 2010 changes to the lead monitoring requirements,9 DAQ began lead monitoring at the
Raleigh Millbrook NCore site on Dec. 27, 2011, using the low-volume PM10 monitor already at the site.
This lead monitoring ended on April 30, 2016, when new monitoring regulations became effective.10 As
shown in Figure D61, the Raleigh MSA does not have any permitted facilities located within its bounds
that emit 0.5 ton or more of lead per year so no other lead monitoring is required. 11

9 Revisions to the Lead Ambient Air Monitoring Requirements, Federal Register, Vol. 75, No. 247, Monday, Dec.
27, 2010, available on the worldwide web at https://www.gpo.gov/fdsys/pkg/FR-2010-12-27/pdf/2010-
32153.pdf#page=1.
10 Revisions to Ambient Monitoring Quality Assurance and Other Requirements, Federal Register, Vol. 81, No. 59,
Monday, March 28, 2016, available on the worldwide web at https://www.gpo.gov/fdsys/pkg/FR-2016-03-
28/pdf/2016-06226.pdf.
11 Data obtained from the 2020 EPA Toxics Release Inventory Tracker available at
https://edap.epa.gov/public/extensions/TRIToxicsTracker/TRIToxicsTracker.html#.

D-24

Figure D61. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the Raleigh MSA
(4) Rocky Mount MSA
The Rocky Mount MSA consists of two counties: Edgecombe and Nash. The major metropolitan area is
the City of Rocky Mount. DAQ currently operates one monitoring site in the Rocky Mount MSA, located
in Edgecombe County at Leggett as shown in Figure D62.

Figure D62. Monitoring site location in the Rocky Mount MSA

D-25

At the Leggett site, DAQ operates a seasonal ozone monitor and a non-regulatory continuous fine
particle monitor. The ozone monitor is no longer required for the MSA. In April 2011, the division added
a continuous fine particle monitor to the site to enable real-time fine particle air quality index reporting
and fine particle forecasting. Figure D63 through Figure D71 show the site as well as views looking north,
northeast, east, southeast, south, southwest, west and northwest.
Figure D63. Leggett seasonal ozone and air quality index fine particle monitoring site
Figure D64. Looking north from the Leggett site
Figure D65. Looking northwest from the Leggett site
Figure D66. Looking northeast from the Leggett site
Figure D67. Looking east from the Leggett site

D-26

Figure D68. Looking west from the Leggett site
Figure D69. Looking southwest from the Leggett site
Figure D70. Looking southeast from the Leggett site
Figure D71. Looking south from the Leggett site
Changes made to the lead monitoring requirements in December 2010 did not require additional
monitoring in the Rocky Mount MSA. As shown in Figure D72, the MSA does not have any permitted
facilities located within its bounds that emit 0.5 tons or more of lead per year. 12

Figure D72. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the Rocky Mount MSA

12Data obtained from the 2020 EPA Toxics Release Inventory Tracker available at
https://edap.epa.gov/public/extensions/TRIToxicsTracker/TRIToxicsTracker.html#.

D-27

The 2015 changes to the ozone monitoring requirements did not require additional monitoring in the
Rocky Mount MSA. The MSA already has the minimum number of monitors required by 40 CFR Part 58,
Appendix D for population exposure monitoring in urban areas. As of 2017, the seasonal ozone
monitoring begins a month earlier on March 1 instead of April 1.
The 2010 nitrogen dioxide monitoring requirements did not add any monitors to the Rocky Mount MSA
because its population is less than a million. The 2010 sulfur dioxide monitoring requirements also did
not require additional monitors in this area because there are no large sources of sulfur dioxide in the
MSA. This area will also not need any carbon monoxide monitors due to the changes to the carbon
monoxide monitoring requirements because the population is under one million.
(5) The Wilson Micropolitan Statistical Area
The Wilson MiSA consists of Wilson County. There currently is no Metropolitan Statistical Area in Wilson
County; however, the Wilson MiSA is located here. The Wilson area population is staying about the
same or shrinking somewhat. The North Carolina Office of State Budget and Management projects the
population in Wilson County will decline through 2023 and then begin to increase as shown in Figure
D73.13 DAQ currently does not operate any monitoring sites in the Wilson MiSA.

Figure D73. Wilson County Population Projections

13 North Carolina Office of State Budget and Management, Standard Population Estimates, Vintage 2020 and
Population Projections, Vintage 2021, July 1, 2020 to July 1, 2029, last updated Jan. 27, 2022, available on the
worldwide web at https://www.osbm.nc.gov/media/2267/download?attachment, accessed April 30, 2022.

D-28

The lead monitoring requirements in December 2010 affected the Wilson MiSA because it had a
permitted facility located within its bounds that emitted more than 0.5 tons per year of lead.14 Saint-
Gobain Containers, LLC, reported 2009 lead emissions of 0.84 tons. DAQ requested and received a
waiver for Saint-Gobain based on the results of modeling. Model results indicate the maximum ambient
lead concentration in the ambient air at and beyond the fence-line is 0.015 micrograms per cubic meter,
well below the 0.075 micrograms per cubic meter or 50 percent of the NAAQS threshold for monitoring.
The EPA renewed the waiver in 2015 based on 2011 National Emission Inventory emissions of 0.53 tons
of lead. The waiver was good until 2020.15 The division requested a renewal of the waiver in 2020. The
EPA declined to renew the waiver because in 2018, Ardagh Glass, the former Saint Gobain Containers,
reported 427.1 pounds of lead emissions,16 which is less than the 0.5 ton threshold requiring a waiver. In
2020, Ardagh Glass reported 456 pounds of lead emissions. 17 Figure D74 shows the county-wide lead
emissions for 2009 through 2020. 18

Figure D74. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the Wilson MiSA

14 Data obtained from the DAQ emission inventory database available online at
https://xapps.ncdenr.org/aq/ToxicsReport/ToxicsReportFacility.jsp?ibeam=true&county_code=195&year=2009&s
orting=103&overridetype=All&pollutant=153.
15 2015 State of North Carolina Ambient Air Monitoring Network Plan, The U. S. EPA Region 4 Comments and
Recommendations, p7, available at
http://xapps.ncdenr.org/aq/documents/DocsSearch.do?dispatch=download&documentId=7440.
16 United States Environmental Protection Agency. (2018). TRI Explorer (2018 Updated Dataset (released April
2020)) [Internet database]. Retrieved from https://enviro.epa.gov/triexplorer/tri_release.facility, (April 11, 2020)
17 Data obtained from the 2020 EPA Toxics Release Inventory Tracker available at
https://edap.epa.gov/public/extensions/TRIToxicsTracker/TRIToxicsTracker.html#
18 Data obtained from the 2020 EPA Toxics Release Inventory Tracker available at
https://edap.epa.gov/public/extensions/TRIToxicsTracker/TRIToxicsTracker.html#

D-29

Changes to the ozone monitoring requirements in 2015 did not require additional monitoring in the
Wilson MiSA. Until it becomes an MSA, it does not have to meet population exposure monitoring
requirements for urban areas. The Office of Management and Budget did not reclassify the Wilson MiSA
as an MSA in February 2013 when it revised the MSA classifications. The next scheduled revision for
MSA classifications is in 2023; however, sometimes the Office of Management and Budget adjusts
classifications between the scheduled revisions. Using the latest data available, the Wilson municipality
is almost 1,000 people short of meeting the classification requirements for a metropolitan statistical
area.
The 2010 nitrogen dioxide monitoring rule did not require the Wilson MiSA to do any nitrogen dioxide
monitoring. Its population is less than 500,000 and the annual average daily traffic measured on its
roadways is below the threshold for monitoring. It also is not required to do sulfur dioxide monitoring by
the 2010 sulfur dioxide monitoring rule because the population is too small and the sulfur dioxide
emissions are too low to trigger PWEI monitoring. This area is also not required to do carbon monoxide
monitoring by the changes to the carbon monoxide monitoring requirements because the population is
under 1,000,000.
(6) The Sanford Micropolitan Statistical Area
The Sanford MiSA consists of Lee County. DAQ started a monitoring site in the Sanford MiSA in
November 2013. The Blackstone monitoring station supported a special study to monitor baseline
ambient air near potential shale-gas development areas in Lee County.19 Ozone monitoring started on
Nov. 1, 2013, and a continuous fine particle monitor started Jan. 1, 2014. In December 2014, DAQ added
a sulfur dioxide monitor and nitrogen dioxide monitor. The site also monitored for volatile organic and
carbonyl toxic compounds and hydrocarbons. DAQ shut down this monitoring station on July 31, 2018.
Figure D75 shows where the site was located. For more information on this site, see the report: Baseline
Air Quality Assessment: Deep River Basin, Lee County North Carolina 20 or the 2018-2019 Annual
Monitoring Network Plan for the North Carolina Division of Air Quality, Volume 2, Site Descriptions by
Division of Air Quality Regional Office and Metropolitan Statistical Area, D. the Raleigh Monitoring
Region.21

19 Department of Environment and Natural Resources, Division of Air Quality, Project Plan for Baseline Ambient Air
Monitoring near Potential Shale Gas Development Zones in Lee County, NC, Updated Nov. 8, 2013. Available online
at https://www.deq.nc.gov/monitor/specialstudies/daq-project-plan/open, accessed on May 22, 2023.
20 Department of Environmental Quality, Division of Air Quality, Baseline Air Quality Assessment: Deep River Basin,
Lee County North Carolina, July 12, 2018. Available on the worldwide web at https://www.deq.nc.gov/baseline-air-
quality-assessment-deep-river-basin/open.
21 Department of Environmental Quality, Division of Air Quality, 2018-2019 Annual Monitoring Network Plan for
the North Carolina Division of Air Quality, Volume 2, Site Descriptions by Division of Air Quality Regional Office and
Metropolitan Statistical Area, D. the Raleigh Monitoring Region, June 29, 2018. Available on the worldwide web at
http://xapps.ncdenr.org/aq/documents/DocsSearch.do?dispatch=download&documentId=10637.

D-30

Figure D75. Location of the former monitoring site in the Sanford MiSA
The Sanford MiSA was not required to do any lead monitoring to comply with changes made to the lead
monitoring requirements in December 2010. As shown in Figure D74, there are no facilities located
within its bounds that emit more than 0.5 tons per year of lead.22
Figure D76. Lead and Lead Compound Releases to the Air from 2009 to 2020 in the Sanford MiSA

22 Data obtained from the 2020 EPA Toxics Release Inventory Tracker available at
https://edap.epa.gov/public/extensions/TRIToxicsTracker/TRIToxicsTracker.html#.

D-31

Changes to the ozone monitoring requirements in 2015 did not require additional ozone monitoring in
the Sanford MiSA. Until the Sanford municipality grows large enough for the Office of Management and
Budget to classify it as an MSA, it does not have to meet population exposure monitoring requirements
for urban areas.
The 2010 nitrogen dioxide monitoring rule did not require the Sanford MiSA to do any nitrogen dioxide
monitoring. Its population is less than 500,000 and the annual average daily traffic measured on its
roadways is below the threshold for monitoring. The 2010 sulfur dioxide monitoring rule also did not
require any sulfur dioxide monitoring in this area because the population is too small and the sulfur
dioxide emissions are too low to trigger PWEI monitoring. This area is also not required to do carbon
monoxide monitoring by the changes to the carbon monoxide monitoring requirements because the
population is under 1,000,000.

D-32

Appendix D.1 Annual Network Site Review Forms for 2022
Durham Armory in Durham
Bushy Fork
Butner
Northampton County
West Johnston in Johnston County
Millbrook in Raleigh
Triple Oak Road in Cary
Leggett

D-33

D-34

D-35

D-36

D-37

D-38

D-39

D-40

D-41

D-42

D-43

D-44

D-45

D-46

D-47

D-48

D-49

D-50

D-51