Ms. Myra Reece 

UNITED STATES ENVIRONMENTAL PROTECTION AGENCY 

REGION 4 

ATLANTA FEDERAL CENTER 

61 FORSYTH STREET 

ATLANTA, GEORGIA 30303-8960 

ocr s- zot4 

Chief, Bureau of Air Quality Control 

South Carolina Department of Health and 

Environmental Control 

2600 Bull Street 

Columbia, South Carolina 29201 

Dear Ms. Reece: 

Thank you for submitting the state of South Carolina's 2014 annual ambient air monitoring network plan 

(Network Plan) dated July 3, 2014. The Network Plan is required by 40 Code of Federal (CPR) 

Regulations §58.10. 

The U.S. Environmental Protection Agency Region 4 understands that the South Carolina Department of 

Health and Environmental Control (SC DHEC) provided the public a 30-day review period for its draft 

Network Plan. Comments on the draft plan were submitted by six stakeholders and the final Network 

Plan includes the SC DHEC response to these comments. 

With this letter, the EPA Region 4 is approving the Network Plan provided that the following changes 

are made: 

1. An ozone (03) monitoring site must be established in the Myrtle Beach-Conway-North 

Myrtle Beach, SC-NC Metropolitan Statistical Area (MSA) by the beginning of the 2015 

ozone monitoring season. 

2. Air Quality Index reporting for the Myrtle Beach-Conway-North Myrtle Beach, SC-NC MSA 

must be initiated once the 03 monitoring site is established. 

Details regarding our review of the Network Plan are provided in the enclosed comments. 

Internet Address (URL) • http://www.epa.gov 

Recycled/Recyclable • Printed with Vegetable Oil Based Inks on Recycled Paper (Minimum 30% Postconsumer) 
Thank you for working with us to monitor air pollution and promote healthy air quality in South 

Carolina. If you have any questions or concerns, please contact Gregg Worley at (404) 562-9141 or 

David McNeal at (404) 562-9102. 

Enclosure 

cc: Mr. Robert Brown 

Division Director, Air Planning Development 

and Outreach, SC DHEC 

Mr. Scott Reynolds 

Beverly H. Banister 

Director 

Air, Pesticides and Toxics 

Management Division 

Director, Division of Air Quality Analysis, SC DHEC 

Mr. Thomas Flyrm 

Manager, Air Data Analysis and Support Section, SC DHEC 

The Honorable William Harris 

Chief of the Catawba Indian Nation 

Mr. Darin Steen 

Director, Environmental Services, Catawba Indian Nation 
CY 2014 State of South Carolina Ambient Air Monitoring Network Plan 

The U.S. EPA Region 4 Comments and Recommendations 

This document contains the U.S. EPA Region 4 comments and recommendations regarding the state of 

South Carolina's 2014 ambient air monitoring network plan (Network Plan). Ambient air monitoring 

rules, which address network plans, data certification, and minimum monitoring requirements, among 

other requirements, are found in 40 CFR part 58. Minimum monitoring requirements for criteria 

pollutants are listed in 40 CFR part 58, appendix D. Minimum monitoring requirements are listed for 

ozone (03), particulate matter less than 2.5 microns (PM2.s), particulate matter less than 10 microns 

(PM10), nitrogen dioxide (N02), sulfur dioxide (S02), carbon monoxide (CO), and lead (Pb). 

The minimum monitoring requirements are based on core based statistical area (CBSA) boundaries as 

defined by the U.S. Office of Management and Budget (OMB), July 1, 2013, population estimates from 

the U.S. Census Bureau, and historical ambient air monitoring data. Minimum monitoring requirements 

for 03, PM2.s, and PM10 only apply to metropolitan statistical areas (MSAs) which are a subset of 

CBSAs. OMB currently defines 10 MSAs in the state of South Carolina. These MSAs and the respective 

July 1, 2013, population estimates from the U.S. Census Bureau are shown in Table 1. 

Table 1: Metropolitan Statistical Areas and Populations 

MSAName 

Charlotte-Gastonia-Concord NC-SC 

Greenville-Anderson-Mauldin, SC 

Columbia, SC 

Charleston-North Charleston-Summerville, SC 

Augusta-Richmond County, GA-SC 

Myrtle Beach-Conway-North Myrtle Beach, SC-NC 

Spartanburg, SC 

Florence, SC 

Hilton Head Island-Bluffton-Beaufort, SC 

Sumter, SC 

Minimum OJ Monitoring Requirements 

40 CFR part 58, appendix D, table D-2 

Population 

2,335,358 

850,965 

793,779 

712,220 

580,270 

404,951 

318,999 

206,261 

198,467 

108,123 

Region 4 has determined that the 03 monitoring network outlined in the Network Plan meets the 

minimum requirements found in 40 CFR part 58, appendix D, table D-2 for nine of the MSAs in South 

Carolina. Due to changes that OMB made to MSA boundaries in February of2013, Brunswick County, 

North Carolina has been added to the Myrtle Beach-Conway-North Myrtle Beach, SC-NC MSA. This 

change triggered the requirement for an 03 monitor in the MSA, and the 2014 Network Plan indicates 

that the SC DHEC has entered into discussions with North Carolina and other stakeholders to identify an 

appropriate location for a new monitoring site. 

Since the need for an 03 monitoring site in the Myrtle Beach-Conway-North Myrtle Beach, SC-NC 

MSA has been known since early 2013, Region 4 believes that a reasonable deadline for beginning the 

required monitoring would be the beginning of the 2015 ozone season (April2015). 
Minimum PM1o Monitoring Requirements 

40 CFR part 58, appendix A, 3.3.1 

40 CFR part 58, appendix D, table D-4 

Region 4 has determined that the PM10 monitoring network outlined in the Network Plan meets or 

exceeds the minimum requirements found in 40 CFR part 58, appendix D, table D-4 for all MSAs. Also, 

all manual PM10 collocation requirements are met. 

Minimum PM2.s Monitoring Requirements 

40 CFR part 58, appendix A, 3.2.5 

40 CFR part 58, appendix D, table D-5 

Region 4 has determined that the PM2.s monitoring network outlined in the Network Plan meets or 

exceeds the minimum requirements found in 40 CFR part 58, appendix D, table D-5 for all MSAs. Also, 

all PM2.s collocation requirements are met. 

PM2.s Continuous Monitoring Requirements 

40 CFR part 58, appendix D, 4.7.2 

Regulatory provisions for continuous PM2.s monitoring require that "The State, or where appropriate, 

local agencies must operate continuous PM2.s analyzers equal to at least one-half(round up) ofthe 

minimum required sites listed in Table D-5 of this appendix. At least one required continuous analyzer 

in each MSA must be collocated with one of the required FRMIFEM/ARM [Federal Reference 

Method/Federal Equivalent Method/Approved Regional Method] monitors, unless at least one of the 

required FRMIFEM/ ARM monitors is itself a continuous FEM or ARM monitor in which case no 

collocation requirement applies." After review of the Network Plan, Region 4 has determined that the 

proposed PM2.s continuous monitoring network meets or exceeds the minimum requirements in all of 

the MSAs in the state. Also, the continuous PM2.s collocation requirements are met in all MSAs. 

PM2.s Background and Transport Sites 

40 CFR part 58, appendix D, 4.7.3 

40 CFR part 58, appendix D, 4.7.3 requires that "Each State shall install and operate at least one PM2.s 

site to monitor for regional background levels and at least one PM2.s site to monitor for regional 

transport." The 2014 Network Plan identifies Ashton (AQS ID 45-029-0002) in Colleton County as a 

regional background site and Chesterfield (AQS ID 45-025-0001) in Chesterfield County as a regional 

transport site. Therefore, the SC DHEC has satisfied the requirements of 40 CFR part 58 for regional 

background and transport sites. 

PM2.s Chemical Speciation Network 

The EPA has been conducting an assessment of the Chemical Speciation Network (CSN) in an effort to 

optimize the network and create a network that is sustainable going forward. As a result of this 

assessment, EPA is recommending defunding a number of monitoring sites, eliminating the CSN PM2.s 

mass measurement, reducing the frequency of carbon blanks, reducing sample frequency at monitoring 

sites, and reducing the number oficepacks in shipments during the cooler months ofthe year. 
The EPA is currently soliciting feedback regarding their recommendations. Should these 

recommendations become final, the CSN monitors at the Chesterfield (AQS ID 45-025-0001) and the 

Greenville ESC (AQS ID 45-045-0015) sites would need to be shutdown. The CSN PM2.s mass 

measurement is recommended for elimination in July 2014 and all other changes are recommended to 

take place in January 2015. Final changes to the CSN in the state of South Carolina will need to be 

reflected in the 2015 Network Plan. 

Pb Monitoring Requirements 

40 CFR part 58, appendix D, 4.5 

40 CFR part 58, appendix D, 4.5 requires that "At a minimum, there must be one source-oriented 

SLAMS [State and Local Air Monitoring Station] site located to measure the maximum Pb 

concentration in ambient air resulting from each non-airport Pb source which emits 0.50 or more tons 

per year and from each airport which emits 1.0 or more tons per year ... " 

Although South Carolina has no sources that exceed the thresholds for Pb monitoring, the Johnson 

Control Battery Group conducts source-based ambient Pb monitoring at three sites around the Florence 

Recycling Center in Florence, South Carolina. The company is conducting this monitoring under terms 

of a settlement agreement reached with several petitioners who commented on the construction permit 

for the facility. Locations for the monitoring sites were selected based upon an agreement between the 

company and the stakeholders. According to the 2014 Network Plan, a collocated Pb monitor has been 

added to one of the three existing sites for quality assurance purposes. 

40 CFR part 58, appendix D, 3(b) requires that "NCore sites in CBSAs with a population of 500,000 

people (as determined in the latest Census) or greater shall also measure Pb either as Pb-TSP or PbPMIO." The Network Plan indicates that a Pb sampler is located at the Parklane NCore site (AQS ID 45-

079-0007). 

The Pb monitoring network described in the Network Plan meets all of the design criteria of 40 CFR 

part 58. 

Sulfur Dioxide (S02) Monitoring Requirements 

40 CFR part 58, appendix D, 4.4 

Ambient air monitoring network design criteria for S02 are found in section 4.4 of 40 CFR part 58, 

appendix D. This section requires that "The population weighted emissions index (PWEI) shall be 

calculated by states for each core-based statistical area (CBSA) ... " As a result, the S02 monitoring 

site(s) required in each CBSA will satisfy minimum monitoring requirements if the monitor(s) is sited 

within the boundaries of the parent CBSA and is of the following site types: population exposure, 

maximum concentration, source-oriented, general background, or regional transport. An S02 monitor at 

an NCore station may satisfy minimum monitoring requirements if that monitor is located within a 

CBSA with minimally required monitors consistent with appendix D, section 4.4. Based upon PWEis 

calculated using the latest population estimates and emission inventory data, the minimum number of 

monitors required for the CBSAs in South Carolina is summarized in Table 2. 

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Table 2: S02 Monitoring System Status 

CBSAName 

Augusta-Richmond County, GA-SC 

Charleston-North Charleston-Summerville, SC 

Charlotte-Gastonia-Concord NC-SC 

Columbia, SC 

Greenville-Anderson-Mauldin, SC 

SLAMS 

required 

1 

1 

1 

1 

1 

SLAMS 

present 

1 

1 

1 

1 

1 

Based upon the information summarized in Table 2, the S02 monitoring network outlined in the 

Network Plan meets the design criteria specified in section 4.4 of appendix D to 40 CFR part 58. 

N02 Monitoring Requirements 

40 CFR part 58, appendix D, 4.3 

Ambient air monitoring network design criteria for N02 are found in Section 4.3 of appendix D to 40 

CFR part 58. Three types ofN02 monitoring are required: near-road, area-wide, and Regional 

Administrator. These types ofN02 monitoring are described in sections 4.3.2, 4.3.3 and 4.3.4, 

respectively. 

Ambient air monitoring design criteria for near-road N02 monitoring sites are found in section 4.3.2 of 

appendix D to 40 CFR part 58. The requirement for near-road monitoring in the Charlotte-GastoniaConcord NC-SC CBSA will be met using the Remount site (AQS ID 3 7 -119-0045) operated by 

Mecklenburg County's Land Use and Environmental Services Agency (MCLUESA) in Charlotte, North 

Carolina. No other CBSA in South Carolina is currently required to have near-road N02 monitoring. By 

January, 1 2017, South Carolina CBSAs with populations over 500,000 will be required to operate nearroad N02 monitoring. 

Ambient air monitoring network design criteria for area-wide N02 sites are found in section 4.3.3 of 

appendix D to 40 CFR part 58. The Garinger High School site (AQS ID 37-119-0041) currently 

operated by MCLUESA will be used for fulfilling the area-wide N02 monitoring requirement for the 

Charlotte-Gastonia-Concord NC-SC CBSA. No other CBSA in South Carolina is required to have an 

area-wide N02 monitor. 

Ambient air monitoring network design criteria for Regional Administrator required N02 monitoring, 

often referred to as RA-40 monitoring, are found in section 4.3.4 of appendix D to 40 CFR part 58. 

Under these provisions Regional Administrators must require a minimum of 40 additional N02 

monitoring stations nationwide, with a primary focus on siting these monitors in locations to protect 

susceptible and vulnerable populations. As part oflast year's Network Plan review, Region 4 selected 

the Greenville ESC site (AQS ID 450-045-0015) as a RA-40 N02 monitoring site. 

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Air Quality Index (AQI) Reporting 

40 CFR §58.50 

AQI reporting is required in MSAs with populations over 350,000. Four MSAs in the state of South 

Carolina are required to report an AQI: Greenville-Anderson-Mauldin, Columbia, Charleston-North 

Charleston, and Myrtle Beach-Conway-North Myrtle Beach, SC-NC. The Network Plan on Page 3 

indicates that the daily AQI for all of these areas except the Myrtle Beach-Conway-North Myrtle Beach, 

SC-NC MSA is available on EPA's AIRNow web site. Once an 03 monitoring site is added to the 

Myrtle Beach-Conway-North Myrtle Beach, SC-NC MSA in order to satisfy the minimum requirements 

in 40 CFR part 58, AQI reporting should also be initiated. 

Proposed Monitoring Network Changes 

SC DHEC has proposed nine monitoring network change~ which are summarized in Table 3. 

Table 3: Pro~osed Monitorin; Network Chan;es 

AQSID Site Name Pollutant Type Comments 

45-019-0003 Jenkins Ave Fire Station so2 SLAMS Editorial correction 

45-091-0006 York so2 SPM Change designation 

45-063-0008 lrmo SVOCs Non-regulatory Change objective 

45-063-0008 Irmo Carbonyls Non-regulatory Change objective 

45-045-0015 Greenville ESC N02 SLAMS Change designation 

45-045-0015 Greenville ESC so2 SLAMS Change designation 

45-077-0002 Clemson 03 SLAMS Add monitor 

45-025-0001 Chesterfield PM2.5 speciation Supplemental Discontinue monitoring 

45-073-0001 Long Creek PM2.5 SPM Change designation 

The designation for the SOz monitor at the Jenkins Avenue Fire Station site (AQS ID 45-019-0003) was 

changed from SPM to SLAMS in order to correct an error in the previous Network Plan. 

The Network Plan proposes to change the designation for the SOz monitor at the York site (AQS ID 45-

091-0006) from SLAMS to SPM. The basis for this change is that there are currently two operational 

SOz SLAMS in the Charlotte-Gastonia-Concord CBSA, but only one is required due to substantial 

decreases in emissions that have lowered the PWEI in the CBSA. The other SOz SLAMS in the CBSA 

is located at the Garinger High School NCore site (AQS ID 37-119-0041) in Mecklenburg County, 

North Carolina. The York site has been in operation since January of 2012, and SOz concentrations at 

the site are consistently lower than at the Garinger High School site. Therefore, the proposal to change 

the SOz monitor designation at the York site to SPM is acceptable. 

The objective for the semi-volatile organic compound (SVOC) and carbonyl monitors at the Irmo site 

(AQ ID 45-063-0008) was changed to non-regulatory in order to be consistent with the objective for the 

black carbon monitor located at the site. 

The designation for the NOz monitor at the Greenville ESC site (AQS ID 45-045-0015) was changed 

from SPM to SLAMS to reflect its selection as an RA-40 NOz monitoring site. 

5 
The designation for the S02 monitor at Greenville ESC site (AQS ID 45-045-0015) was changed from 

SPM to SLAMS since the latest PWEI calculations indicate that an S02 SLAMS is required in the 

Greenville-Anderson-Mauldin MSA. 

In its 2013 Network Plan, SC DHEC proposed to discontinue 03 monitoring at the Clemson site (AQS 

ID 45-077 -0002). Because this proposal was not approved, information regarding Clemson site was 

included in the 2014 Network Plan. 

The Network Plan proposes to discontinue PM2.s speciation monitoring at the Chesterfield site (AQS ID 

45-025-0001) if funding for this activity is discontinued by EPA. 

The designation for the PM2.s monitor at the Long Creek site (AQS ID 45-073-0001) was changed from 

SLAMS to SPM due to the inadequate performance of the monitor. The Long Creek site is located in a 

county (Oconee) that is not part of a MSA for which minimum monitoring requirements are specified 

under 40 CFR part 58, appendix D. 

Based upon our review, all of the proposed changes in the 2014 Network Plan are acceptable. 

National Core (NCore) Monitoring Network 

40 CFR part 58, appendix D, 3 

A requirement that each state operate at least one NCore site is found in section 3 of 40 CFR part 58, 

appendix D. The state's approved NCore site is located at the Parklane site (AQS ID 45-079-00047) and 

the SC DHEC has not proposed any changes for the site in its 2014 Network Plan. 

6