### DEPARTMENT 

### of ENVIRONMENT and NATURAL RESOURCES PMB 2020 JOE FOSS BUILDING 523 EAST CAPITOL PIERRE, SOUTH DAKOTA 57501-3182 www.state.sd.us/denr

June 2, 2011 James B. Martin Regional Administrator U.S. Environmental Protection Agency, Region 8 1595 Wynkoop Street Denver, CO 80202-1129 Dear Mr. Martin: On March 24, 20II, EPA notified the Governor ofSouth Dakota that EPA revised the sulfur dioxide National Ambient Air Quality Standard and initial area designations are due by June 3, 2011. EPA revised the primary sulfur dioxide standard by adding a I-hour average concentration. On January 18, 2011, Governor Daugaard submitted a letter to you designating the Secretary of the Department ofEnvironment and Natural Resources as his designee for submitting designations and other matters which involves South Dakota's Air Quality Program. In that capacity, I recommend EPA designate all counties in South Dakota as attaining the I-hour sulfur dioxide standard (see Attachment A) based on the attached supportive document. Attachment B provides the technical analysis for designating all ofSouth Dakota's counties in attainment. Attachment C provides a copy ofthe Air Quality System AMP450 repOli showing the yearly 99th percentile concentrations for each site and includes the one year ofdata collected near the Big Stone Power Plant in Roberts County. Thank you for the opportunity to propose designations for the revised primary sulfur dioxide standard and I look forward to your concurrence. Ifyou have questions, please contact Brian Gustafson at 605-773-3151.

# ~, Steven M. Pimer Secretary Attachments RECEIVED cc: Monica Morales, EPA Region 8 U.S. EPA Region 8 RA's Office 

## JUN 07 

## 2011**.~.** 

### Attachment A South Dakota Area Designations I-hour Sulfur Dioxide Standard
Desi2Dated Area Desi2nation Type Classification Type Aurora County Attainment Beadle County Attainment Bennett County Attainment Bon Homme County Attainment Brookin2s County Attainment Brown County Attainment Brule County Attainment Buffalo County Attainment Butte County Attainment Campbell County Attainment Charles County Attainment Clark County Attainment Clay County Attainment Codin2ton County Attainment Corson County Attainment Custer County Attainment Davison County Attainment Day County Attainment Deuel County Attainment Dewey County Attainment Dou21as County Attainment Edmunds County Attainment Fall River County Attainment Faulk County Attainment Grant County Attainment Gregory County Attainment Haakon County Attainment Hamlin County Attainment Hand County Attainment Hanson County Attainment Hardin2 County Attainment HU2hes County Attainment Hutchinson County Attainment Hyde County Attainment Jackson County Attainment Jerauld County Attainment Jones County Attainment Kin2sbury County Attainment Lake County Attainment

A-IDesi2l1ated Area Designation Type Classification Type Lawrence County Attainment Lincoln County Attainment Lyman County Attainment Marshall County Attainment McCook County Attainment McPherson County Attainment Meade County Attainment Mellette County Attainment Miner County Attainment Minnehaha County Attainment Moody County Attainment Pennington County Attainment Perkins County Attainment Potter County Attainment Roberts County Attainment Sanborn County Attainment Shannon County Attainment Spink County Attainment Stanley County Attainment Sully County Attainment Todd County Attainment Tripp County Attainment Turner County Attainment Union County Attainment Walworth County Attainment Yankton County Attainment Ziebach County Attainment

A-2

### AttachmentB DeterminingAreaDesignations 1. Air Monitoring Sulfur dioxide I-hour concentrations in South Dakota are low statewide. The highest design value concentration was recorded at the SD School Site in Sioux Falls at 19% ofthe new I-hour standard. The Badlands and Wind Cave sites have the lowest design value concentrations at 8% ofthe standard. The concentrations in South Dakota are low for several reasons. First, the state'spopulation and sulfur dioxide emissions from area sources are low. Second, all but five sources with Title V air quality permits in the state emit sulfur dioxide emissions less than 100 tons per year. Finally, sulfur dioxide emissions from area sources will continue to decline because ofthe move to ultra low sulfur fuels that began in 2010. Table B-1 displays the three year calculated design value concentration for each site. The design value concentration for the SD School, Wind Cave, and Badlands Sites used data from 2008 to 2010. Both Union County sites have onlytwo years ofdata. Roberts Countyonly has 13 months ofdata

. hi B 1 S' D

. 

### V. 

### a ues

I 

## c . S

### out ota a e 

## - - lte eSll(n oncentrations In hD 

### ak

I 

### Site County 99th 

### Percentile 3-YearA**vera~e** 

### Attainment SD School Minnehaha 2008

- 27 parts perbillion 14 parts perbillion Yes 2009

- 10 partsperbillion 2010- 5 parts perbillion Badlands Jackson 2008 - 5parts perbillion 6 parts perbillion Yes 2009 - 5 parts per billion 2010- 9 parts perbillion Wind Cave Custer 2008 - 3 parts perbillion 6 parts per billion Yes 2009

- 10 partsperbillion 2010- 5parts perbillion UC#l Union 2009

- 10 parts perbillion 11 parts perbillion I 2010

- 12 parts perbillion UC#2 Union 2009 - 6 parts perbillion 7 parts perbillion I 2010- 9parts perbillion Big Stone II Roberts 2001 - 5 parts perbillion 10 parts perbillion I 2002

- 14 parts perbillion

_ Not comparable to the standard because there is less than 3 years ofdata. The sulfur dioxide I-hour concentrations collected in the state during the years of2001 to 2002 and 2008 to 2010 demonstrate there were no I-hour concentrations exceeding the new primary standard as calculated following the form ofthe standard. Thehighest three year average was recorded at the SD School Site with a three year average concentration level of 14 parts perbillion. Figure B-1 provides a graph comparison ofthe design values for each site compared to the I-hour sulfur dioxide standard. Although the Big Stone II, Union County#1 and Union County#2 Sites do not have three years ofdata, the two year average ofthe 99th percentile is provided for comparison purposes. B-1

### FigureB-1

- Data Comparedto the I-hourSulfurDioxideStandard 

# Ic=J3-YearA-.erage -Standard

# I

80 70

r:::: 60**~A** 11 

# H 6 6 

# I 

# I I I I I 

### - 0 50 iii



## ... <Il 40 11. 30 III 20 11. 7 10 

# I I I

0 SO School Badlands Wind Ca-.e UC#1 UC#2 Sites

The Badlands and Wind Cave sites represent rural areas consisting mainly ofrangeland and forested areas in the western halfofSouth Dakota while the Union County sites represent the farming area in the eastern halfofSouth Dakota. The SD School Site represents South Dakota's largestpopulated area in the Sioux Falls Metropolitan Statistical Area (MSA). The Big Stone II site represents sulfur dioxide concentrations near South Dakota's largest emitting sulfur dioxide source. Based on the monitoring data which reflects the potential highest and lowest sulfur dioxide concentrations in the state, South Dakota is attaining the I-hour sulfur dioxide National Ambient Air Quality Standard in every county in the state. 

### 2. AirModeling EPA's Memorandum from Stephen D. Page to Regional Air Division Directors, I-X, dated March 24, 2011, indicates EPA may initiallydesignate an area as attainment ifit is clearit meets the new sulfur dioxide National AmbientAir Quality Standards (NAAQS). EPA further states it does not believe it would be appropriate to designate areas as attainment without appropriate refined dispersion modeling and where available, air quality monitoring data indicatingno violations ofthe NAAQS. DENR agrees modelingmaybe used as a tool by states but disagrees it is the onlytool to demonstrate attainment for the following reasons: 1. DENR recently used AERMOD to model the impacts ofan existing coal-fired electricpower plant using sulfur dioxide emissions beingreported to EPA in accordance with the Acid Rain Program. A receptor was placed on two ambient air qualitymonitoring sites to compare hourly monitoring data to the hourlymodeling data. This comparison assumed no other sulfur dioxide emitting sources were impacting the monitors. In realty, ifthe model was accurate, the modelingresults would be less than the monitoringresults. The comparison indicated AERMOD mayover-predictthe concentrations ofsulfur dioxide greater than a factor oftwo (see Appendix D for analysis).
B-22. In accordance with 40 CFR Part 51, Appendix W, uncertainties and accuracy ofthe models are discussed. As noted in section 9.1.2, Studies ofModel Accuracy, "(1) Models are more reliable for estimating longer time-averaged concentrations than for estimating short-term concentrations at specific locations; and (2) the models are reasonably reliable in estimating the magnitude ofhighest concentrations occurring sometime, somewhere within an area. For example, errors in highest estimated concentrations of± 10 to 40 percent are found to be typical, i.e., certainly well within the often quoted factor-of-two accuracy that has longbeen recognized for these models. However, estimates ofconcentrations that occur at a specific time and site are poorly correlated with actually observed concentrations and are much less reliable." 3. EPA did not provide states or the public an opportunityto comment on EPA's new policy of placingmore confidence on a model for designations than ambient air quality monitoring. In the proposed rule, EPA stated itwould use monitoring for designation purposes butin the final rule it required modeling for attainment designations. This flip flop was initiated byone city and three states suggestingthe use ofmodeling for designations. Ifyou tumthis around, 47 states and therest ofthe nation's cities agreed monitoring should beused for designations. 4. This flip flop is also contraryto EPA's previous decisions, court cases, and rule: a. On page 26382 ofthe Federal Register, Vol. 43, No. 118, June 19,1972,EPA states in the preamble to the 1977 PSD rules, "

...EPA intends that monitoring should generally focus on obtaining data necessary for required review against NAAQS. Although the increment consumption must ofnecessitybe tracked through the use of modeling, EPA does not intend that there be no "real world" checks on the accuracy ofmodeling." b. In Alabama Power Co. v. Costle C.A.D.C. 1979, the U.S. Court ofAppeals, District of Columbia Circuit states, "Wediscern from the statute a technology-forcing objective. Congress intended that monitoring would impose a certain discipline on the use of modelingtechniques, which would be the principal device relied upon for the projection of the impact on air quality ofemissions from a regulated source. This projects that the employment ofmodelingtechniques beheld to earthbya continual process of confirmation and reassessment, aprocess that enhances confidence in modeling, as a means for realisticprojection ofair quality." c. This is further emphasized by EPA's current rules under the Prevention ofSignificant Deterioration program. In accordance with 40 CFR §52.21(m)(2), ifthe Administrator believes it is necessary, the owner or operator shall conduct ambient air qualitymonitoring, "

...to determine the effect emissions from the stationary source ormodification mayhave, or are having, on air quality in any area." Even after a PSD sourcehas demonstrated it is can construct and operate and not cause a violation ofthe National Ambient Air Quality standard or PSD incrementusing modeling, EPAmayrequire a source to conduct monitoring to ensure the modelingprovided realistic results and no violations will occur. Historically, both Congress and EPA intended for monitoring to be the real determination on ifan area is attaining the National Ambient Air Quality Standards. IfEPA wants to use modeling as the only tool to designate areas attaining ornot attaining the I-hour sulfur dioxide standard, the actual requirement to use modeling should havebeen proposed in the rule to allow everyone an opportunity to comment on this decision. DENR believes monitoringprovides the reality check both Congress and EPA believe are necessary for states to demonstrate an area is attaining ornot attaining the standard and should be used for the I-hour sulfur dioxide standard.

B-3

### 3. SulfurDioxide MonitoringNetworkin SouthDakota The first sampling effort in South Dakota to collecthourly sulfur dioxide data was near the Big Stone PowerPlant. Themonitoring location for sulfur dioxide was based on modelingindicatingthe area of highest concentrations near the facility and in South Dakota. A continuous 12-monthperiod ofair monitoring was completed in the years of2001 and 2002 as part ofa Prevention ofSignificant Deteriorationpermit application. Sulfurdioxide levels were low with a 99th percentile I-hour average concentration level of 10 parts perbillion. DENR operates a network ofair monitoring sites whichbegan collectinghourly sulfur dioxide data in 2002. The first site was established at the Hilltop Site in Sioux Falls. Themonitor was later moved to the SD School Site and continues today. In 2005, two more locations were added at the Badlands and Wind CaveNational Parks. In 2009, two more locations were added in Union County. The current sampling network includes sites in several counties around the state with goals ofhigh concentration, population, source impact, background and regional transport. See Figure B-2 for a map ofthe state showing the counties with sulfurdioxide airmonitoring data. 

### FigureB-2

- SouthDakota Counties with SulfurDioxideData

Legend 3 Years of Data 

## 0 2 Years of Data _ 1 Year of Data 

## 0 No Sampling

B-4

### 4. South Dakota's Population and SulfurDioxide Emissions IfEPA still wishes to use a policyofusing modeling for designationpurposes, the final rule onpage 35551 states, "

...we believe that for a short-term I-hour standard it is more technically appropriate, efficient, and effective to use modeling as the principle means ofassessing compliance for medium to larger source, and to rely more on monitoring for groups ofsmall sources and sources not as conductive to modeling." Sulfurdioxide emissions from Title V major sources throughout South Dakota are low to medium with one source that couldbe considered large. Table B-2 provides alist ofthe top 10 major sources emitting sulfur dioxide in calendaryear 2009 and represents 75% ofthe state's total emissions from permitted sources.

# 

### County 1 Grant 2 Pennington 3 Pennington 4 Brookings 5 Sioux Falls 6 Brookings 7 Spink 8 Turner 9 Minnehaha 10 Codington 

### Table B-2

- Top 10SulfurDioxideEmitters in SouthDakota (tonsperyear) Facility OtterTail PowerCompany

- Big Stone I Black Hills Corporation

- BenFrench GCC Dacotah South Dakota State University John Morrell & Company Valero Renewable Fuels Company Redfield Energy Great Plains Ethanol Sioux Falls WaterReclamation Facility Glacial Lakes Energy 

### TonslYear 11,651 823 285 183 170

85 42 21 13 11 

### 13,284 17,826 Top 10 Total = 

### Total for Entire State South Dakotahas counties with low population and no large sources ofsulfur dioxide emissions as canbe seen in Table B-2. The sulfur dioxide concentrations in these areas would be similar to the concentrations South Dakota is experiencing at its Badlands, Wind Cave, and Union County monitoring sites depending on what rural area one is located. DENRbelieves these sites meet EPA's requirement that monitoring should be used for designationpurposes, not modeling. South Dakota has other counties with low population and several sources ofsulfur dioxide that would not be considered large sources ofsulfurdioxide emissions (see Attachment E). These counties would have concentrations somewhere in between the concentrations at the rural sites and SD School Site. DENRbelieves these sites meet EPA's requirement that monitoring should beused for designation purposes, not modeling. The largest city in South Dakota is Sioux Falls with a population ofless than 153,888. The largest of the three MSAs in the state includes the cityofSioux Falls and includes the counties ofMinnehaha, Lincoln, McCook, and Turner. The combined 2010 Census population for the Sioux Falls MSA is 228,261. Table B-3 provides a list ofthe top 10 mostpopulated counties in the state and the largest city within the county. Thelargestpopulated area in South Dakotahas sources ofsulfur dioxide

B-5emissions that would notbe considered large sources ofsulfur dioxide. DENRbelieves even this site meets EPA's requirement that monitoring should be used for designation purposes, not modeling

. hi



### e B



## -3



### - H: 

### IgJ

h

### est opu ation C 

### a ota a en Pl' 

### ountles In . S

### out hD k 

### County Population Population Number**Lar~est** 

### City Minnehaha 169,468 Sioux Falls 153,888 

### 1 Pennington Rapid City 67,956 100,948 2 44,828 153,888 Lincoln Sioux Falls 

### 3 26,091 Brown 36,531 Aberdeen 4 22,056 Brookings 31,965 Brookings 

### 5 27,227 Watertown 21,482 Codington 6 25,434 Sturgis 6,627 Meade 

### 7 24,097 Spearfish 10,494 Lawrence 

### 8 22,438 14,454 Yankton Yankton 9 15,254 19,504 Mitchell Davison 

### 10 Grant Countyhas the highest emission total for sulfur dioxide in South Dakota and the emissions are generated by the Big Stone I Power Plant. DENRdoes notbelieve modeling is necessary even at this site since modeling was used to detennine the location ofhighest concentrations and an ambient air monitorwas located at the modeling site in Roberts County and recorded concentrationsjustover 13% ofthe I-hour sulfur dioxide standard. In addition, sulfur dioxide emissions will be lowered from Big Stone I once the control equipment required bythe Regional Haze Program is installed. Therefore, even Grant County should be designated attainmentbased onmonitoringresults.

B-6

### Attachment C Air Quality System Report AMP450

UNITED STATES ENVIRONMENTAL PROTECTION AIR QUALITY SYSTEM QUICK LOOK REPORT (AMP450) AGENCY

May 11, 2011

Sulfur**dioxid~** (42401) P 0 IrE 1D c PQAO CITY 46-033-0132 3 0973 Not in a city

46-033-0132 3 0973 Not in a city

46-033-0132 3 0973 Not in a city

46-071-0001 3 0973 NOt if'l a city

46-071-0001 3 0973 Not in a city

46-071-0001 3 0973 Not in a city

16-099-0008 3 0973 Sioux falls
46-099-0008 3 0973 Sioux falls
46-099-0008 3 0973 Sioux Falls
46-109-4003 3 0973 Not in a city 46-109-4003 3 0973 Not in a city 46-127-0001 3 0973 Not in a city COUNTY Cugter

Custer

Custer

Jackson

Jackson

Jack.son**~innehaha** Hinnehaha
Minnehaha
Roberts Robert.s Union ADDRESS YEAR WIND CAVE 200S NATIONAL PARK, SOUTH DAKOTA WIND CAVE 2009 NATIONAL PARK, SOUTH DAKOTA WIND CAVE 2010 NA.TIONAL PARK, SOUTH DAKOTA BADLANDS PO .2008 BOX 6 HEADQUARTER 5 BADLANDS PO 2009 BOX 6 HEADQUARTER S BADLANDS PO 2010 BOX 6 HEADQUARTER 5 2001 E 8th 2008 St 2001 88th 2009 St 2001 E 8th 2010 St 482ND AVE 2001 48.2ND AVE 2002 319B6 475th 2009 Ave South Dakota

COMP METH aBS QTRS 060 8678 4

060 6487 3

060 8640 4

060 8616 4

060 8645 4

060 8307 4

060 8095 3
060 8184 4
060 8678 4
060 1390 0 060 6935 3 560 8589 4 15T MAX I-HR

4.0

32.0

16.0

7.0

7.0

17.0

31.0
18.0
6.0
5.0 28.0 10.5 2ND MAX I-HR

4.0

20.0

10.0

6.0

6.0

11. 0

30.0
14.0
6.0
5.0 20.0 10.0 99TH perL I-HR

3.0

10.0

5.0

5.0

5.0

9.0

27.0
10.0
5.0
5.0 14 .0 9.6 15T MAX 24-HR

1.4

5.7

2.8

6 0

3.2

3.7

10.0
2. B
1.9
.7 5.3 4.3 2ND MAX 24-HR

1.3

3.0

2.6

5.0

2.9

3.3

B.9
2.3
1.7
.7 4.0 3.5 Parts per Days >24HR ARITH

STD MEAN 0 .23

0 .53"

0 .12

0 1. 28

0

. B4

0 1. 04

0 .89
0 .20
0 .25
0 .04 • 0 .19* 0 .22 bililon

CERr EDT

N

N N (008)

Note; The" not satisfy iQdicates that the summary criterla. mean does Page 2 of 5

C-l,.

UNITED STi\TES**~NV!RONMENrAL** PROTECTION AGE:NCY AIR QUALITY SYSTEM QUICK LOOt<**R~PORT** (A.HP450)
May. 11, 2011

Sulfur dioxide (42401) South Dakotd: PartS per billion (008) p 1ST 2NO**99T~** 1ST 2ND Days 0 COMP MAX MAX PCrL MAX MAX >24HR ARItH IrE ID c PQAO crry COUNTY ADDRE:SS YEAR METH OBS QTRS l-KR 1-Hl' 1-KR 24-HR 24-HR STD MEAN CERT EDT 3 0973 Not in .a C1ty Union 31986 475th 2010 560 8640 4 30.3 26.0 11.5 8.2 4.2 0 .40 Ave 46-127-0002 3 0973 Not in a city Onion 31307 473rd 2009 560 8657 4 9.0 9.0 6.0 3.3 1.3 0 .16 Ave 46-127-0002 3 0973 Not 1n a city Union 31307 473rd 2010 560 8628 26.2 15.9 8.6 3.8 3.5 0 .32 

### • Ave

Note: The .. indicaces. that the mean does not sacisfy**~ul1Lq:ary** criteria. Page 3 of 5

C-2

### Attachment D AERMOD Modeling Accuracy This analysis was taken from DENR's section 4.4.1

- ModelingAccuracy ofthe Statement ofBasis for Hyperion Energy Center's extension request for it Prevention ofSignificant Deterioration air quality permit#28.0701-PSD. 4.4.1 Model Accuracy Themodeling analysis indicates Hyperion will not cause orcontribute to a violation ofthe new I-hour sulfurdioxide National Ambient Air Quality Standard; but the analysis does show the modeled concentration plus the background monitoring concentration is within 2 percent ofthe new I-hour sulfur dioxide National Ambient Air Quality Standard. Therefore, DENR considered several factors involvinghow realistic the models predict the concentration and what facility or facilities is contributingto the modeling concentration. The high modeled sulfur dioxide concentrations are located in the southeast corner ofthe modeling domain. The facility contributing to the high modeled concentration for sulfur dioxide (greater than 90% contribution) is the MidAmerican George Neal facilities in Iowa. Duringthese periods when MidAmerican George Neal is the majority contributor, Hyperion's contribution is less than 1%. In accordance with 40 CFR Part 51, Appendix W, uncertainties and accuracy ofthe models are discussed. As noted in section 9.1.2, Studies ofModel Accuracy, "(1) Models are more reliable for estimating longer time-averaged concentrations than for estimating short-term concentrations at specific locations; and (2) the models are reasonably reliable in estimatingthe magnitude ofhighest concentrations occurring sometime, somewhere within an area. For example, errors in highest estimated concentrations of± 10 to 40 percent are found to be typical, i.e., certainly well within the often quoted factor-of-two accuracy thathas longbeen recognized for these models. However, estimates ofconcentrations that occur at a specific time and site, are poorlycorrelated with actually observed concentrations and are much less reliable." To determine ifthe AERMOD is correctly quantifying the sulfur dioxide concentration, DENR conducted a screeningtest to determine ifAERMOD would meet a minimum operational performance for the I-hour sulfur dioxide National Ambient Air Quality Standard. DENR used the fractional bias procedure identified in EPA's Protocol for Determiningthe Best Performing Model (EPA

- 454/R-92­ 025). DENR modeled MidAmerican George Neal facilities actual emissions from March 31, 2009 through March 31, 2010, at two receptorpoints in South Dakotausing the two meteorological data sets for Union County. The two receptorpoints used were the location ofthe two sulfur dioxide monitoring stations currentlybeing operated byDENR in Union County. The modeled results were then compared to the monitored results using the screening approach specified in EPA'sprotocol. Since the new I-hour sulfur dioxide National AmbientAir Quality standard represents a new form of a standard, DENR compared both the highest 25 hourlyreadings and the highest 25 readings representing the form ofthe standard (e.g., highest 25 daily I-hour values). Figure 4-1 shows a graphical representation ofthe screeningtest. As identified in theprotocol "Models that plot close to the center (0,0) are relatively free from bias, while models that plot further
0-1away from the center tend to overorunder-predict. Values equal to -0.67 are equivalent to overpredictions bya factor oftwo while values equal to +0.67 are equivalent to under-predictions by a factor oftwo. As the graph indicates, AERMOD over-predicts the concentrations ofsulfurdioxide with five ofthe eight scenarios indicating the model would over-predict the concentrations greater than a factor oftwo. 

### Figure 4-1

- 

### Screening Test

-­ Under-predicts '----­ 

## - impacts

...........

-­**.~** -1.5 -I 45

## ~M 1 1.5

............ 

# /

# 1000r-pre~ IImpacts 

# I
Bias ofAverage
• UCSF #1 Standard • UCSF #1 Hourly • UCSF #2 Standard • UCSF #2 Hourly • UCSC #1 Standard. UCSC #1 Hourly • UCSC #2 Standard. UCSC #2 Hourly
Based on the analysis, the model is over-predicting the impact MidAmerican GeorgeNeal will have on the sulfur dioxide concentrations in the modeling domain. Ifit is over-predicting MidAmerican George Neal it is also likely over-predicting all ofthe sources in the area includingHyperion. Since the approved models are inherently conservative, DENRbelieves actual monitoring data will be lower then what is beingpredicted bythe models.

D-2

### Attachment E South Dakota's Sulfur Dioxide Emissions From National Emission Inventory Table E-I contains sulfur dioxide emissions data from the National Emission Inventory (NEI) for 2002 and 2009. The 2002 NEI was included because the inventory included a calculation ofemission from area and fugitive sources ofsulfurdioxide. Union County is shown as the fourth highest county with sulfur dioxide emissions even though there are no existingTitle V sources in the countythat emits sulfur dioxide emissions in that quantity. DENR investigated this further and found the sulfur dioxide emissions in the 2002 NEI inventory are the result ofcoal burning. There is no coal burning facility in Union County. Therefore, the information for Union County is inaccurate. The 2009 emissions are from Title V sources only. Table E-l- Sulfur Dioxide Emissions in 2002 and 2009 County 2002 NEI Emissions (tons) 2009 TitleV Source Emissions (tons) Grant 11,918.8 11,652.0 Minnehaha 3,320.1 182.4 Pennington 2,738.6 1,118.1 Union 1,531.7 0.0 Brookings 1,237.7 267.5 Codington 904.6 11.5 Brown 680.6 2.9 Yankton 603.2 0.2 Davison 431.2 1.1 Lincoln 295.3 0.9 Beadle 290.8 0.3 Lake 263.1 2.4 Hutchinson 202.7 0.0 Lawrence 179.5 2.3 Spink 160.2 41.7 Roberts 158.1 0.1 Bon Homme 143.2 0.1 Marshall 140.4 0.0 Meade 135.7 0.0 Kingsbury 134.7 0.2 Day 131.9 0.0 Charles Mix 128.5 0.0 Moody 111.2 0.0 McCook 108.6 0.0 Clay 107.3 1.0 Turner 99.7 23.4 Clark 98.1 1.0 Edmunds 91.7 8.9

£-1County 2002 NEI Emissions (tons) 

### 90.6 90.3 87.9 87.3 85.2 83.1 80.4 76.1 74.7 72.8 72.7 68.7 68.2 66.4 65.8 63.9 63.4 2009 Title V Source Emissions (tons) 

### 0.0 0.0 0.0 0.0 2.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 2.3 0.5 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.1 0.0 0.0 0.0 0.0 0.0 0.0 Fall River Tripp Hamlin Hand Deuel Custer Perkins Sanborn Hughes Lyman Potter Miner Butte Walworth Gregory Brule Faulk Douglas 

### 59.2 56.1 55.2 54.8 52.5 51.0 50.1 44.7 44.0 41.6 36.2 35.5 33.6 32.6 30.8 29.9 22.8 15.7 13.7 11.1 McPherson Haakon Hanson Sully Aurora Corson Jackson Campbell Todd Jones Bennett Jerauld Hyde Dewey Shannon Stanley Mellette Ziebach Harding Buffalo 

### 9.1 28,425 

### 0.0 13,323

Statewide Total

£-2