H>tate of H>cmtf) Carolina

Office of tfje <§otoernor

NIKK I R. HALEY 1205 PENDLETON STREET

GOVERNOR COLUMBIA 29201

June 2, 2011

Gwendolyn Keyes Fleming, Esq.

Regional Administrator

US EPA Region 4

Atlanta Federal Center

61 Forsyth Street, S.W.

Atlanta, GA 30303-8909

Re: South Carolina Recommendations for Sulfur Dioxide (SO2) Boundary Designations

Dear Ms. Fleming,

This letter is in response to the United States Environmental Protection Agency's (EPA) request to submit

boundary recommendations for the revised 1-hour primary National Ambient Air Quality Standard (NAAQS) for

Sulfur Dioxide (SO2) established by the EPA via 75 Federal Register 35520, June 22, 2010. Pursuant to this

request, I recommend that each county in the state of South Carolina be designated as attainment for the

new 1-hour primary NAAQS for SO2.

Background and Rationale

Let me first say, with the EPA Administrator's commitment to uphold the values of transparency and openness in

conducting EPA operations, I am disappointed in the way that EPA introduced the use of air dispersion modeling

as the principal indicator for implementation of the SO2 NAAQS. Failure to openly and adequately engage the

public in decisions that have far reaching economic implications during these difficult budgetary times is not in

the public's best interest. In addition, I am concerned with EPA's historical practice of using guidance in lieu of

rulemaking to impose regulatory requirements on the states, as guidance is not developed through a robust public

involvement process.

In terms of historical practices, the EPA states in its February 1994 (EPA-452/R-94-008) SO2 Guidance

Document, that "modeling may be necessary to determine the representativeness of the monitored data," and that

these factors "should be considered interdependently." The new designation stance taken by the EPA in its March

24, 2011, memo Area Designations for the 2010 Revisions to the Primary Sulfur Dioxide National Ambient Air

Quality Standards is not in line with its historical practices with regard NAAQS implementation and is contrary to

the explicit expression of the standard.1 Based on the current guidance it appears that EPA will be making

attainment decisions based entirely on modeled concentrations using federally enforceable maximum allowable

l40CFR§5850.17(b)
Gwendolyn Keyes Fleming, Esq.

Page 3

June 2, 2011

emissions.2 This is a departure from the way in which attainment modeling has been done for all other NAAQS,

which instead uses actual/typical emissions.3 For example, Section 17.3, p. 172 of EPA's current attainment

modeling document states: "For point sources, hourly Continuous Emissions Monitoring data are recommended

for use in model-evaluation runs. For future-year runs, we recommend creating an 'average-year' or 'typical year'

temporal allocation approach that creates representative emissions for the 'baseline inventory' but that also

includes similar daily temporal variability as could be expected for any given year." With EPA's new approach,

contrary to attainment demonstrations based on monitoring data, attainment decisions will be based on simulated

concentrations based on fictional operating scenarios rather than empirical data based on the actual operation of

these sources and ambient air quality monitor measurements. Further, this overly conservative modeling approach

will falsely identify areas as not meeting the new standards, wasting resources on additional modeling efforts

and/or emission controls/operating changes that could have been directed at priorities deemed important to bring

about air quality improvements. South Carolina already has a monitoring network and permitting program

addressing NAAQS attainment review with flexibility to address implementation of the new SO2 standard. The

permitting process for new and modified sources (including PSD projects) should drive sources to show they do

not cause or contribute to an exceedance of a NAAQS, not the NAAQS attainment designation process.

The South Carolina Department of Health and Environmental Control (SCDHEC) currently requires, under State

Implementation Plan (SIP) approved State Regulation 61-62.1 Definitions and General Requirements, Section

II.C.3.n and Section II.H.i, that all construction permit applications (along with modifications) include "An air

dispersion modeling analysis or other information demonstrating that emissions from the facility, including those

in the application, will not interfere with the attainment or maintenance of any ambient air quality standard." Let

me reinforce that our state's review requirement applies to any new or modified source requiring an air

construction permit and assures that facilities do not cause or contribute to an exceedance of a NAAQS and

applies to all sources - not just the very largest Prevention of Significant Deterioration (PSD) sources that EPA

requires to be modeled. SCDHEC has had this process in place for over twenty (20) years and requiring SCDHEC

and businesses to rerun dispersion modeling for all potential SO2 sources in the state, especially at a time when

our state has faced unprecedented budget cuts, is unnecessary and redundant.

With regard to monitors, South Carolina currently operates seven SO2 monitors: Greenville ESC (45-045-0015),

Long Creek (45-073-0001) Irmo (45-063-0009), Parklane (45-079-0007), Congaree (45-079-0021), Jenkins (45-

019-0003), and Cape Romain (45-019-0046). A map of these monitors is included in Attachment 1. Six of these

seven monitors are currently documenting design values below the 75 parts per billion (ppb) 1-hour standard. The

Irmo monitor has indicated a design value of 80 ppb based on data from 2008, 2009 and 2010.

Evaluation by SCDHEC of available data indicates that the predominant cause of high values at this monitor is

emissions from the SCE&G McMeekin facility (Title V Permit 1560-0003). The Irmo SO2 monitor, located

approximately 3.5 miles due east (see Attachment 1) of the facility, was sited to specifically monitor SO2 impact

from the facility's units. In an effort to achieve cleaner air sooner than would otherwise be required by processes

outlined in the Clean Air Act, SCDHEC began meeting with SCE&G last year to discuss options to control air

emissions at this source. As a result, SCE&G has agreed to and is currently implementing the use of lower sulfur

content coal than that which the McMeekin facility is currently permitted to use. They are also making other

operating restrictions which will further reduce SO2 emissions. A Memorandum of Agreement (MOA) between

the state and SCE&G outlining these requirements has been executed. (The facility's title V permit is under

review for renewal and the MOA will be addressed during this review.) A copy of this MOA is included as

Attachment 2.

2 Area Designations for the 2010 Revisions to the Primary Sulfur Dioxide National Ambient Air Quality Standards, March

24, 201, Page 4 "Identifying attainment areas."

3 Guidance on the Use of Models and Other Analyses for Demonstrating Attainment of Air Quality Goals for Ozone, PM2.5,

and Regional Haze (EPA -454/B-07-002), April 2007.
Gwendolyn Keyes Fleming, Esq.

Page3

June 2, 2011

The EPA continues to remind us that many new federal rules will further reduce SO2 ambient air concentrations

throughout the nation and will help most areas attain the SO2 NAAQS. The "Transport Rule" as proposed August

2, 2010, would reduce power plant SO2 emissions by 71 percent over 2005 levels by 2014.4 As a co-benefit of air

toxics reductions, the National Emission Standards for Hazardous Air Pollutants From Coal and Oil-Fired

Electric Utility Steam Generating Units standard as proposed May 3, 2011, will reduce SO2 emissions from power

plants by up to 55 percent once fully implemented,5 and National Emission Standards for Hazardous Air

Pollutants for Major Sources: Industrial/Commercial/Institutional Boilers and Process Heaters (as proposed) and

National Emission Standards for Hazardous Air Pollutants From the Portland Cement Manufacturing Industry

standards are expected to reduce annual SO2 emissions by 340,0006 tons and 110,0007 tons, respectively.

Based on the decreased SO2 emissions from the changes at the McMeekin facility and the new federal rules,

downward trends in SO2 concentrations throughout the state are expected. Because of these decreased SO2

emissions, the Irmo monitor is expected to meet the revised SO2 NAAQS before area designations must be

finalized on June 3, 2012. SCDHEC expects to submit 2011 monitoring data which demonstrates full attainment

of the 75 ppb 1-hour standard in early 2012.

I would like to thank you for considering this designation request and should you have any questions regarding

the state's recommendation, please contact Myra Reece, Chief, Bureau of Air Quality, at (803) 898-4123 or by

email atreecemc@dhec.sc.gov.

Sincere!

cc: Mr. C. Earl Hunter, Commissioner, SCDHEC; Mr. Robert W. King, Jr., P.E., Deputy Commissioner, EQC,

SCDHEC; Ms. Myra C. Reece, Chief, BAQ, SCDHEC

Attachments:

1. Data illustrating the contribution of SCE&G's McMeekin facility (TV Permit #1560-0003) to levels at the

Irmo monitor (45-063-0009).

2. MOA and/or Proposed Title V amendments for SCE&G's McMeekin facility.

4 As indicated in the preamble of Federal Implementation Plans To Reduce Interstate Transport of Fine Paniculate Matter

and Ozone (15 FR 52210, August 2, 2010).

5 Preamble, National Emission Standards for Hazardous Air Pollutants From Coal- and Oil-Fired Electric Utility Steam

Generating Units and Standards of Performance for Fossil-Fuel-Fired Electric Utility, Industrial-Commercial- Institutional,

and Small Industrial- Commercial-Institutional Steam Generating Units (76 FR 24976, May 3, 2011).

6 As indicated in the preamble of National Emission Standards for Hazardous Air Pollutants for Major Sources: Industrial,

Commercial, and Institutional Boilers and Process Heaters (76 FR 15608, March 21, 2011).

7 As indicated in the preamble of National Emission Standards for Hazardous Air Pollutants From the Portland Cement

Manufacturing Industry and Standards of Performance for Portland Cement Plants (75 FR 54970, September 9, 2010).
Attachment 1 

Data Illustrating the Contribution of SCE&G’s 

McMeekin Facility to Levels at the Irmo Monitor 

SC Recommendations for SO2 Boundary Designations 

June 2, 2011

Attachment 1 – Page 1
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SC Recommendations for SO2 Boundary Designations 

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Attachment 1 – Page 2
I. Background

South Carolina currently has seven SO2 monitors: Greenville ESC (45-045-0015), Long Creek (45-

073-0001), Irmo (45-063-0009), Parklane (45-079-0007), Congaree (45-079-0021), Jenkins (45-019-

0003), and Cape Romain (45-019-0046). 

Figure 1: Map of monitors located in the state. 

As illustrated in Figure 2, the state’s historical design values have shown an overall downward trend. 

Six of these seven monitors are currently showing design values below the 75 parts per billion (ppb) 1-

hour standard; however, the Irmo monitor is showing a design value of 80 ppb which is 5 ppb above 

the current standard. 

Figure 2: Historical Trends in SO2 Design Values at the Irmo Monitor 

SC Recommendations for SO2 Boundary Designations 

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Attachment 1 – Page 3
The Irmo monitor’s SO2 design values have had the highest design values statewide since it 

began monitoring in 1989, and has consistently been greater than the new SO2 NAAQS. 

However, from 1991 – 2010, there was a 40 percent reduction in SO2 design values in Irmo from 

134 ppb to 80 ppb, which is similar to the statewide average reduction of 37 percent during the 

same time period. 

Evaluation of available data indicates that the cause of high values at this monitor is due to emissions 

from the SCE&G McMeekin facility. 

II. McMeekin Facility Description 

The McMeekin facility (TV Permit #1560-0003) is a Title V electric steam generating facility located 

immediately east of SC Hwy 6 and the Dreher Shoals dam in Lexington County, approximately 3.5 

miles due west of the Irmo SO2 monitor and is flanked by a river valley which funnels into a relatively 

flat plane where the monitor is situated. The facility has an elevation of approximately 210 feet above 

sea level, and has primary stack which is 400 feet tall. 

Figure 3: Topographical Map of the Irmo Monitor/McMeekin Facility Area. 

Operations at the McMeekin facility consists of coal handling systems, two coal-fired boiler units and 

associated ash handling facilities. Each boiler is a Combustion Engineering model WT pulverized coal, 

water-tube boiler rated at 1,134 x 106 Btu/Hr (910,000 pounds of steam/hr). Each boiler is coupled to 

two steam turbines. The high-pressure and medium-pressure turbines are on a common shaft driving a 

General Electric (GE) 75 MW generator. Low-pressure steam exiting the first turbine is routed over to 

a secondary turbine that drives a 25 MW GE generator. Total nominal output is 125 MW per boiler, 

SC Recommendations for SO2 Boundary Designations 

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Attachment 1 – Page 4
and it is currently permitted to emit 3.5 lb SO2/106

 BTU at each unit (7 lbs SO2 /106 BTU total). This 

emission limit allows for the use of approximately 2.3 percent sulfur coal based on current pollution 

controls. 

III. Evaluation of Meteorological and Monitoring Data at Times of Exceedences 

Wind patterns in the Columbia area show dominant winds from the west, though there are significant 

southwestern and northeastern components. Figure 4 is a wind rose of 2007-2009 data from the 

Columbia/Metro Airport, approximately 7 miles away from the McMeekin facility and Irmo monitor 

respectively. 

Figure 4: Wind Rose of all Meteorological Data from Columbia/Metro Airport Station 

(2007-2009) 

Wind patterns before, during, and after times of exceedences of the 75 ppb standard, however, are 

almost completely out of the west as indicated in Figure 5. 

SC Recommendations for SO2 Boundary Designations 

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Attachment 1 – Page 5
Figure 5: Wind Rose of Meteorological Data Before, During and After Exceedences of 

the 75 ppb standard from Columbia/Metro Airport Stations (2007-2009) 

The clear wind bias at the time of exeedences indicates that high readings at the Irmo monitor are 

entirely due to a source to the west of the monitor. This would implicate the SCE&G McMeekin 

facility as the primary contributor to high ambient SO2 concentrations at the monitor as it is the 

primary producer of SO2 emissions in the area and is situated approximately 3.5 miles due west of the 

monitor. The only other major facilities (Title V) emitting SO2 are nearly 50 kilometers east of the 

Irmo monitor. 

V. Comparison of Emissions from Other Local Facilities 

The only other major (Title V) source located near the monitor is the Shaw Industries Group, Inc., 

Plant 8S (TV Permit # 1560-0016) floor manufacturing facility. Actual emissions from this facility 

were less than 7 tpy when last evaluated in 2003. The facility has since not been required to report their 

actual emissions to the Department of Health and Environmental Control (Department), due to being 

below the thresholds required in State Regulation 61-62.1 Section III. This facility, though closer to the 

monitor, has very little effect on monitored readings when compared to the nearly 13,000 actual tpy 

that were emitted from the McMeekin facility in 2008. This is further reinforced by all but one of 32 

hours over 75 ppb (between 2007 and 2009) occurred while winds were from the west as illustrated in 

Figure 5. 

SC Recommendations for SO2 Boundary Designations 

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Attachment 1 – Page 6
Included on the same property as the McMeekin facility is the SEFA Group fly ash processing plant. 

This facility is a conditional major facility and has SO2 emissions below 100 tpy. Again, these 

emission are dwarfed by the 13,000 tpy emitted by the McMeekin facility. 

Figure 6: Illustration of Statewide SO2 Sources Based on Actual Emissions with a 

Detail of Those Sources Within 50 km of the Irmo Monitor. 

VI. Conclusion 

Based on available emissions, meteorological, and monitoring data, exceedences at the Irmo monitor 

are almost entirely attributed to emissions from SCE&G’s McMeekin facility. Exceedences have 

consistently occurred when winds are out of the west and at times when the atmospheric mixing layer 

passes a height of 600 feet. This facility, with its western orientation to the monitor, 600 feet-abovesea-level stack, and actual SO2 emissions, which are several orders of magnitude above all other large 

facilities in the area, is the primary cause of exceedences at the Irmo monitor. 

SC Recommendations for SO2 Boundary Designations 

June 2, 2011

Attachment 1 – Page 7