/

" ''-"i. , UNITED STATE S ENVIRONMENTA L PROTECTIO N AGENC Y REGIO N 8 159 5 Wynkoo p Stree t DENVER , C O 80202-112 9
' • - v,..,., - ' Phon e 800-227-891 7 http://www.epa.gov/region0 8 Ref: 8P-AR »« 1 2 '"'"> Brian Gustafson , Administrato r Ai r Quality Progra m Sout h Dakot aDepartmen t

o f Environmen t

an dNatural Resource s 52 3 Eas t Capito l Avenu e Pierre , S D 57501-318 2 RE : EPA Regio n 8 Comment s o n Januar y 15 , 201 0 Draf t Regiona l Haz e SI P (FL

M Consultatio n Version ) Dea r Brian : EPA ha s complete dapreliminary revie w o f Sout h Dakota' s January 15 , 201 0 draf t Regional Haz e Stat e Implementatio n Pla n (SIP) , a s receive dvi aemai l throug h you r Federal Lan d Manage r (FLM ) consultatio n process . Our comment s an dquestion s are detaile din th e Enclosur e t o thi s letter
. W e understan dtha t

yo u inten dt o conside r

al l comment s receive do n thi s FL M consultatio n versio n o f

th e Regional Haz e SI P prio r t o preparin g th e document s fo r your publi c notic e an dcommen t

process . Th e final draf

t o f th e SIP , whic h wil l includ e asummar y o f th e FLMs ' comment s an dyou r responses , wil l the n underg o abroade r publi c hearin g proces s prio r t o adoptio n an dsubmissio n t o EPA
. W e emphasiz e tha t w e wil l onl y reac h afinal conclusio n regardin g th e adequac y o f Sout h Dakota' s Regiona l Haz e SI P whe n w e ac t o n th e Sout

h Dakot a Regiona l Haz e SI P revisio n throug h ou r ow n publi c notic e an dcommen t rulemaking
. We wan t t o acknowledg e you r

effort s i n developin g thi s SI P an dworkin g wit h u s t o resolv e concem s relate dt o subject-to-BAR T modelin g fo r Bi g Ston e I
. Thi s effor

t ha s helpe dt o narro w th e issue s significantly ; however , importan t issue s remain
. Ou r

comment s ar e intende dt o assis t yo u i n revisin g th e draf

t SIP before yo u begi n you r publi c hearin g process . Pleas e not e that ou r mos t seriou s concem s ar e summarize da t th e beginnin g o f

th e Enclosure
. A s yo u ar e aware . Sout

h Dakot areceive dafinding o f failure t o submi t

it s Regiona l Haz e SI P b y th e require ddeadline
. A s aresult , a2-yea r cloc k wa s initiate dfo

r EPA t o full

y approv e a SI P o r promulgat e aFedera l Implementatio n Plan by January 15 , 2011
. In orde r t o mee t thi s deadline , w e continu e to advis e yo u t o submi t th e Sout h Dakot aRegional Haz e SI P i n atimel y manner . Pleas e d o no t

hesitat e t o contac t

m e wit h an y concem s relate dt o thi s timeline
.W e hav e appreciate dworkin g with yo u durin g th e revie w o f thi s FL M consultatio n versio n o f th e draf t Regiona l Haz e SI P an dloo k forwardt o continue dcommunication s durin g th e publi c hearin g process . If yo u hav e an y question s o n EPA' s comments , pleas e contac t m e a t 303-312-6434 , o r

you r staf f ma y contac t Gai l Fallo n a

t 303-312-628 1 o r

Am y Piat t a t 303-312-6449
. Sincerely ,

Galli c A
. Videtich , Directo r Ai r Progra m Enclosur e
cc : Chri s Shaver , NP S Sandr aSilva , USFW S Thoma s Dzomba , USF S

- 2 -
Printed on Recycled

Paper 

# ®.ENCLOSUR E

EPA Regio n 8 Preliminar y Comment s o n th e Januar y 15,201 0 Draf tRegiona l Haz e SI P (FL M Consultatio n Version ) Summar y o f

Majo r Concern s - (se e detaile d comment s fo r mor e information) :

• N o justificatio n for

separat e startup/shutdow n limit s fo r PM , SO2 , an dNO.x

. Se e comment s #18-2 0 below
. • N o detail s o n ho w th e BAR T emissio n limit s vsdl l b e mad e enforceabl e a s apractica l matter . Se e comment s # 1 an d#2 1 below
. • N o identificatio n o f

th e numbe r

o f year s t o reac h natura l condition s a s require dwhe n th e Reasonabl e Progres s Goa l i s les s tha n th e Unifor mRat e o f Progress
. Se e commen t

#2 3 below
. • N o 4-facto r

Reasonabl e Progres s analysis
. Se e commen t #2 4 below
. • N o smok e managemen t plan eve n thoug h fire i s identifie da s amajo r contributor
. Se e commen t #3 1 below
. Detaile d Comments ; 1
. Executiv e Summary , pp . viii-ix : (A ) Th e BAR T emissio n limits , complianc e schedules , monitoring , recordkeeping , and complianc e determinin g method s for Bi g Ston e I mus t

b e specifie di

n th e tex t o f th e Regional Haz e SI P o r

i n apermi t

tha t i s incorporate dint o th e SIP
. Yo u not e tha t yo u inten dto establis h th e appropriat e averagin g times , complianc e verificatio n procedures , an d recordkeepin g an dreportin g requirement s i n a n ai r quality constructio n permit
. Sinc e thi s documen t i s no t include di n thi s draf

t SIP , w e woul dlik e t o wor k wit h yo u to ensur e tha

t thes e requirement s ar e adequatel y addresse di n th e SIP
. Not e that th e publi c notic e fo

r th e Regiona l Haz e SI P need s t o includ e notificatio n tha t a n ai r quality permi t

t o addres s BAR T requirement s i s incorporate da s par t o f th e SIP
. Additionally , with MD U Resource s Group' s Novembe r

2 , 200 9 announcemen t

tha t Bi g Ston e II wil l no t

b e built , doe s S D DENRplan t o amen dand/o r

revok e th e existin g permi t provision s i n orde r

t o reflec t th e Company' s announcemen t

an dth e forthcomin g BAR T determination , an dwhat i s th e timelin e fo

r doin g so ? (B ) Th e las t

sentenc e reference s aChapte r 1 2 that wa s no t include din thi s draf

t FL M consultatio n versio n o f

th e SIP ; therefore , w e wer e unabl e t o revie w an dcommen t o n it
. 2
. Chapte r

1 , Introduction , p . 1 : (A ) Pleas e clarif

y that th e 197 7 Clea n Air

Ac t Amendment s an dEPA' s 198 0 reasonabl e attributabl e visibilit y impairmen t regulation s addresse dvisibility impairmen t tha t wa s cause d o r contribute dt o by on e o r asmal l grou p o f

sources . (B ) Pleas e revis e th e dat e for delegatio n o f

th e Preventio n o f

Significan t

Deterioratio n (PSD ) - 1 -programt o Jul y 6 , 1994
. Th e Septembe r 15 , 199 4 dat e i s simpl y whe n EP A provide dnotic e tha t th e delegatio n hadbee n grante da s o f Jul y 6,1994
. 3
. Section s 3.1 , Baselin e Visibility Conditions , an d3.2 , Natural Visibility Conditions , pp.11-16 : (A ) I t appear s that

Appendi x A wil l contai n th e IMPROV E dat ause dt o determin e baselin e visibility ; however , Appendi x A wa s not include dwith thi s draf

t FL M consultatio n versio n o f th e SIP
. (B ) Base do n ou r

revie w o f

WRAP' s Visibilit y Informatio n Exchang e Web Syste m(VIEWS ) an dinformatio n fromth e USFS , i t appear s tha t

ther e ar e som e error s i n th e baselin e an d natura l backgroun dfigures provide di n Table s 3-1 , 3-5 , an d3-7
. W e understan dthat

th e USF S ha s raise dthes e concern s with yo u an drequeste dth e opportunity t o discuss ; therefore , w e wil l loo k

fo r thes e figures t o b e revise daccordingly
. Pleas e not e tha t EPA' s defaul t value s fo r natura l condition s mus t

b e use di n th e curren t

SI P an dan

y refinement s deferre dt o futur e plannin g periods
. (C ) Tabl e 3- 6 addresse s th e weste mnatura l conditions , bu t th e footnote s refer

t o Trijoni s estimate s fo

r bot h Eas t an dWest
. Th e Trijoni s estimate s fo r th e Eas t d o no t nee dt o b e included
. (D ) A colum n mus t

b e adde dto Tabl e 3- 7 t o highligh t th e decivie w improvemen t require d fo r both bes t an dwors t

days
. 4
. Figur e 3-11 , Unifor

mRat e o f

Progress , p . 17 : Thi s figure ha s been omitted
. Perhap s wit h it s inclusion , ou r

followin g commen t

woul db e addressed
. 5
. Tabl e 3-8 , Annua l Unifor mRat e o f

Improvement , p . 18 : Thi s tabl e need s t o includ e th e unifor mrat e o f improvemen t

for th e 1^ ' plannin g perio d(2004-2018 ) fo r th e mos t an dth e leas t impaire ddays , rathe r

tha n leavin g i t

t o th e reade r

t o calculat e fi-omth e annua l number s provided
. 6
. Figur e 3-12 , Unifor

mRat e o f

Improvement , pp . 18-19 : Fo r both Clas s I areas , w e coul dno t determin e th e sourc e o f

th e 201 8 numbers
. Fo r

Badlands , it

appear s tha t

th e 201 8 unifor

m rat e o f progres s shoul db e 14.8 9 dV (base do n th e 1 4 yea r 1^ ' plannin g period ) instea do f 15.0 4 dV , an dfo

r Win dCave , 13.9 4 d V instea do f 14.0 1 dV
. I n addition , onc e th e baselin e an dnatura l backgroun dvalue s ar e revise dpe r ou r commen t # 3 above , thes e value s wil l nee d t o b e recalculated
. 7
. Sectio n 5.0 , Sourc e Apportionment , pp . 37-58 : (A ) Secfio n 5.1 , Ai r

Emissio n Inventory , pp . 37-38 : I n general , th e WRA P inventorie s utilize dar e adequat e fo

r thi s plannin g period
. However , ther e ar e som e know n shortcoming s wit h th e WRA P inventories , includin g th e oi l an dga s emission s estimates
. Pleas e not e that w e woul dexpec t

futur e review s o f

th e Sout h Dakot aRegional Haz e SI P to rel y on th e mos t current , update demission s inventory
.(B ) Page s 3 9 & 43 : Pleas e elaborat e o n th e "complianc e initiative " relate dto VO C emission s

fro msecondary oi l an dga s productio n i n northweste mSout h Dakota
. Th e draf

t documen t indicates that

th e initiativ e identifie demission s that neede dt o b e addressed , an dit appear s emissio n contro l device s wer e installed
. What stat e mechanism s ar e i n plac e t o ensur e thes e fou r therma l oxidizer s ar e operatin g a t greate r than 98 % control ? (C ) Table s 5-1 , 5-2 , an d5-4 , pp . 40-44 : I n Table s 5- 1 an d5-2 , th e baselin e VO C emission s fromoi l an dga s ar e identifie da s 33,72 1 tons , whil e th e 201 8 projecte dVO C emission s fi"om oi l an dga s ar e show n a s 56 2 ton s i n Tabl e 5-4
. Accordin g t o th e WRA P Technica l Suppor t Syste m(TSS) , th e correspondin g baselin e an dprojecte dVO C emission s fromoi l an dga s are 28 8 ton s an d56 2 tons , respectively
. Thi s larg e discrepanc y betwee n Sout h Dakota' s reporte d number s an dth e WRA P TS S mus t b e explaine di n greate r

detai l i n th e SIP
. I n addition , pleas e explai n whethe r

thes e emission s fromsecondary oi l an dga s productio n wer e use dfo r modelin g an dreasonabl e progres s purposes . We als o not e that Tabl e 5- 1 provide s th e baselin e SO

2 emission s fi'omare asource s a s 10,15 9 tons , whil e Tabl e 5- 2 list s 1,07 1 ton s fromth e sam e source . Thi s ver y substantia l differenc e i s consisten t with value s reporte do n th e WRA P TSS ; however , n o explanafio n i s provided
. Th e SI P tex t mus t provid e clarification
. Finally , ther e appear s t o b e atypographica l erro r i n th e footnote s to Tabl e 5-4 - tw o footnote s labele d"3. " (D ) Table s 5- 6 an d5-7 , p . 46 : W e not e som e discrepancie s compare dwit h wha t wa s include din othe r

stat e plans
. I n orde r

t o ensur e consistenc y wit h othe r states ' assumption s i

t woul db e pruden t

t o verif y thei r emissio n inventory numbers
. Fo r example , th e Nort

h Dakot a draf t pla n list s Nort h Dakot aNO x emission s fo

r 201 8 a t 171,56 6 tons , bu t

th e Sout h Dakot a draf t pla n list s Nort h Dakot aNOx emission s at 187,03 2 ton s fo

r 2018
. (E ) Las t paragraph , p . 54 , an dsecon dparagraph , p . 56 : Ther e may b e typographica l errors , bu t i n an y cas e th e tex t

i s no t consisten t

with th e figures whic h sho w asligh t chang e betwee n 200 2 an d201 8 for

both th e leas t

an dmos t impaire ddays
. Pleas e clarify
. (F ) Firs t paragraph , 2"*

* t o las t sentence , p . 58 : Th e tex t regardin g Montana' s organi c carbo n mas s contributio n mus t

b e clarifie dt o rea dthat , "Natura l fire relate dorgani c carbo n mas s generate din Montan acontribute s approximatel y 34 % o f th e organi c carbo n mas s i n Badland s Nationa l Park. " Sectio n 6.1 , BART-Eligibl e Sources , pp . 70-71 : (A ) Th e definitio n o f

"Dat e o f Reconstruction " doe s no t quit e matc h th e Federal definitio n an dmus t b e revised
. Th e Federa l definitio n i s fo r th e dat e o f

operation , construction , o r reconstructio n an dapplies t o source s that wer e no t in operatio n before Augus t 7 , 196 2 an di

n existenc e a s o f

Augus t 7 , 197 7 with an y reconstructio n occurrin g durin g th e Augus t 7 , 196 2 t o Augus t 7 , 197 7 tim e period
. (B ) Th e las t

sentenc e o f

th e definitio n for

"Potentia l to Emit " contain s atypographical error shoul db e 2 6 categories
. - 3 -9
. Sectio n 6.1.2 , Pet e Lien , pp . 72-73 :

(A ) Ther e appear s t o b e atypographica l erro r i n th e T ^ sentenc e o f

th e first paragrap h - shoul db e worde da s "no t i n operatio n prio r

t o Augus t

7 , 1962... " (B ) Becaus e ther e i s arotary kil n (Uni t 4a ) producin g lim e withi n th e Pet e Lie n facility , Pet e Lie n i s classifie da s alim e plan t accordin g t o th e definitio n in 4 0 CF RPar t 60 , Supar

t HH
. Th e fac t that th e uni t i n questio n unde r

BAR T i s avertica l kil n doe s no t exclud e Pet e Lie n fro mth e lim e plan t

category , sinc e it

doe s hav e arotary kil n producin g lim e withi n th e plant
. Therefore , it

wa s th e appropriat e decisio n t o includ e Pet e Lie n in th e WRA P subject-to-BAR T modelin g analysis
. We wer e unawar e that yo u ha ddetermine dther e wer e error s i n th e modelin g input s an danee dfor are-run . Yo u not e tha t

th e vertica l kil n wa s shutdow n an ddismantle di n 200 9 prio r t o completio n o f

amodelin g re-run . However , th e Novembe r

12 , 200 8 Title V permi t

for Pet e Lie n stil l include s th e vertica l kiln , an dther e ha s no t bee n apermi t

modificatio n t o addres s an y suc h dismantlin g an dclosure
. Eithe r th e permi t need s t o b e modifie dt o reflec t thi s chang e i n statu s o f

th e vertica l kiln , o r

th e modelin g need s to b e re-ru n t o correc t th e inpu t error s an daccuratel y determin e whethe r Pet e Lien i s subjec t

t o BART
. 10
. Sectio n 6.2 , Otte r

Tai l Powe r

Company' s Modelin g Results , pp . 75-77 : W e not e that

th e specifi c versio n o f

CALPUFF , coordinat e gri dpoints , win dfieldoptions , terrain , dispersio n options , recepto r

coordinates , plum e characteristic s an dothe r mode l parameter s approve dby th e DEN Rwer e use dfor

modeling
. Th e DEN Rapprove dprotoco l (/
. e. . th e Augus t 31 , 200 9 Revise dModelin g Protoco l fo r aBAR T Assessmen t

o f th e Bi g Ston e I Coal-Fire dPower Plant ) i s acceptabl e t o EPA ; however , th e modelin g inpu t an doutpu t

files nee dt o b e incorporate dint o th e SI P fo r documentatio n an dpubli c review
. 11
. Sectio n 6.3.2.4 , Sulfia

r Dioxid e Contro l Technolog y Impacts , p . 83 : Footnot e numbe r 3 indicate s abaselin e leve l o f 18,00 0 ton s o f

S02/year ; however , accordin g t o Tabl e 6- 1 on p . 71 , th e baselin e wa s 19,86 3 tons/year
. Thi s large r baselin e figure result s i n a n 81 % emissio n reducfio n fo

r th e 3'^' ' option , a s oppose dt o 90 % wit h th e 18,00 0 tons/year

figure. Pleas e explai n ho w th e 18,00 0 tons/year SO 2 baselin e figure was obtained
. 12
. Sectio n 6.3.3.2 , Technicall y Feasibl e Nitroge n Oxid e Contro l Technologies , pp . 85-86 : At thi s time , w e hav e no t

complete dathoroug h revie w o f you r comment s regardin g commercial availability an dtechnica l feasibility o f th e variou s NO

x contro l technologie s listed
. Therefore , w e ma

y hav e additiona l comment s o n thi s sectio n durin g th e publi c commen t period
. 13
. Tabl e 6-9 , p . 87 : Footnot e 5 reference s a199 9 EP A Technica l Bulleti n o n NO x control s a s justificatio n for

th e 35%-90 % contro l efficienc y rang e fo r th e to p thre e options
. Th e larg e rang e i n EPA' s bulleti n i s du e t o inclusio n o f SCR , selecfiv e non-catalyti c reducfio n (SNCR) , an dfuel rebumin g fo

r wet-botto mboilers
. It

i s wel l documente dthat

SC Rachieve s th e hig h en do f th e range . Th e EP A bullefi n als o list s a30%-70 % contro l efficienc y fo r agrou p o f temperature-reducin g controls , includin g over-fir e air
. Therefore , th e propose dBAR T -4 -determinatio n o f SC Rplu s separate dover-fir e ai r (SOFA ) shoul db e bette r than th e 90 % contro l efficienc y o f

SC Ralone
. It

i s no t clear fromth e SI P tex t

ho w th e propose demissio n limi t wa s calculated ; however , accordin g t o EPA' s Aci dRai n Database , Bi g Ston e I NO x emission s hav e average d0.7 7 Ib/MMBt u ove r th e las t five years . Assumin g acontro l efficienc y greate r

tha n 90 % shoul dresul t

i n alimi t lower tha n th e propose d0. 1 Ib/MMBtu
. 14
. Sectio n 6.3.3.4 , Nitroge n Oxid e Contro l Technolog y Impacts , p . 87 : We assum e yo u ar e relyin g o n Otte r

Tail' s analysi s o f

estimate dcosts , whic h relie do n th e CUECos t model
. Whil e w e ar e satisfie dwit h th e contro l technolog y conclusion s o f you r NO x BAR T determinatio n (i
. e. , SC Rplu s SOFA) , i n genera l w e d o no t recommen drelyin g o n th e CUECos t model
. Accordin g t o th e BAR T Guidelines , i n orde r t o maintai n an dimprov e consistency , cos t

estimate s mus t

b e base do n th e OAQP S Contro l Cos t Manual
. 15
. Tabl e 6-10 , p . 88 : Footnot e 3 contain s typographica l error s - shoul db e nitroge n oxides
. I n addition , similar

t o commen t

#1 1 above , i t

i s tmclea r ho w th e baselin e leve l o f 18,00 0 tons/year

wa s obtained
. Accordin g t o Tabl e 6-1 , p . 71 , baselin e NO x emission s were 17,17 9 tons/year
. Th e large r baselin e figure result s i n a n 89 % emissio n reductio n fo r th e T ' option , a s oppose dt o 93 % with th e 17,17 9 tons/year figure. A s state dabov e i n commen t #13 , acontro l efficienc y greate r tha n 90 % i s appropriat e fo r th e propose dSC Rplu s SOFA controls
. Pleas e explai n ho w th e 18,00 0 tons/year NO x baselin e figure wa s obtained
. 16
. Sectio n 6.3.4 , Visibilit y Impac t Evaluations , 2" ^ paragraph , p . 89 : Again , th e tex t refer s to Bi g Ston e 1 baselin e emission s o f 18,00 0 ton s SO

2 an d18,00 0 ton s NOx
. Pleas e explai n ho w thes e number s were obtained
. 17
. Tabl e 6-12 , p . 89 : Accordin g t o Footnot e 2 o f Tabl e 6-12 , th e rounde dmodelin g value s show n i n th e parenthese s wer e use dt o compar e wit h th e subject-to-BAR T threshold , bu t actually , th e unroundedmodele dvalu e mus t b e use dfo

r determinin g whethe r

asourc e exceed s th e threshold
. 18
. Sectio n 6.3.5.1 , Particulat e Matte r BAR T Recommendafion , p . 95 : (A ) W e assum e DENR' s propose dparticulat e matte r BAR T limi t

o f 0.01 2 Ib/MMBt

u i s on a 30-day rollin g averag e basis , a s required
. Pleas e clarif y i n th e SIP
. (B ) Whil e w e agre e that

abaghous e i s th e to p particulat e contro l technology , wha t i s th e justificatio n fo

r proposin g aseparat e hourl y startup/shutdow n limit ? Th e SI P mus t documen t th e nee dfo

r suc h aseparat e limit , a s wel l a s whethe r th e selecte dvalu e represent s BART
. Ha s DEN Revaluate dpotentia l impact s o f th e separat e startup/shutdow n limi t o n visibility ? Th e BAR T Guideline s contemplat e pound s pe r millio n Bt

u limit s tha t

appl y continuously , with a30-da

y rollin g averag e perio dt o accommodate , amon g othe r things , potentia l short

termfluctuations i n th e emission s rat e that ma y resul t durin g startup , shutdown , an dothe r conditions
. Presumably , you r propose d30-da

y rollin g averag e limi t

alread y include s som e margi n o f safet y fo r operationa l variation
. I f yo u ar e abl e t o justif y th e separat e limits , w e woul dwor

k closel y wit

h yo u a s yo u draf

t appropriat e permi t

languag e t o hel p ensure SI P approvabilit y relate dt o determinin g complianc e wit h th e normal 30-da

y rollin g averag e limi t - 5

-an dth e hourl y startup/shutdow n limit
. Fo r example , in calculatin g 30-day averages , ho w wil l day s b e accounte dfo

r that includ e some , bu t

no t all , hour s o f

startup/shutdown ? 19
. Secfio n 6.3.5.2 , Sulfur Dioxid e BAR T Recommendafion , pp . 96-97 : (A ) We assum e DENR' s propose dSO 2 BAR T limi t

o f 0.0 9 Ib/MMBt

u i s o n a30-da

y rollin g averag e basis , a s required
. Pleas e clarif y in th e SIP
. (B ) A s note din commen t #1 8 above , justificatio n for proposin g aseparat e lb/hou r limi t fo r period s o f startu p an dshutdow n mus t b e provided
. Th e SI P mus t documen t

th e nee dfo

r suc h aseparat e limit , a s wel l a s whethe r th e selecte dvalu e represent s BART
. Ha s DEN R evaluate dpotentia l impact s o f th e separat e startup/shutdow n limi t o n visibility? Th e BAR T Guideline s contemplat e pound s pe r millio n Bt

u limit s that

appl y continuously , wit

h a30-da y rollin g averag e perio dt o accommodate , amon g othe r things , potential short-termfluctuations i n th e emission s rat e tha t

may Resul

t durin g startup , shutdown , an dothe r conditions
. Presumably , you r

propose d30-da

y rollin g averag e limi t

already include s som e margi n o f safet y fo r operationa l variation
. I f yo u ar e abl e t o justif

y th e separat e limits , w e woul dwor k closel y with yo u a s yo u draf t appropriat e permi t

languag e t o hel p ensur e SI P approvability relate dt o determinin g complianc e with th e normal 30-da y rollin g averag e limi t

an dth e hourl y startup/shutdow n limit
. Fo r example , i n calculatin g 30-day averages , ho w wil l day s b e accounte dfo

r that includ e some , bu t

no t all , hour s o f

startup/shutdown ? 20
. Sectio n 6.3.5.3 , Nitroge n Oxid e BAR T Recommendation , pp . 97-98 : (A ) Regardin g th e term"threshold " in referenc e t o $1500/to n fo r NOx removal , EPA' s positio n i s that

th e NO x presumptiv e limit s were establishe dbase do n th e relativel y lo w cos t o f les s tha n $l500/to n fo

r th e majorit

y o f larg e EGUs
. Ther e i s n o brigh t lin e regardin g cos t effectivenes s an deac h determinatio n mus t b e mad e takin g int o accoun t aful l five facto r BAR T analysis
. I

n addition , althoug h Bi g Ston e I ha s acapacity les s than 75 0 MW , it i s greate r than 20 0 M

W an doperatin g withou t

post-combustio n controls
. Pe r th e BAR T Guidelines , i

t i s reasonabl e t o assum e that SC Ri s generall y cost-effectiv e o n larg e cyclon e units
. Se e 7 0 F

R39171 , Juf

y 6 , 2005
. (B ) Pleas e clarif

y tha t DENR' s NO

x BAR T determinatio n i s SC Rplu s SOFA at 0.1 0 Ib/MMBt

u o n a30-day rollin g average . (C ) A s note di n comment s #18-1 9 above , justificatio n fo r proposin g aseparat e lb/hou r limi t fo r period s o f

startu p an dshutdow n mus t b e provided
. Th e SI P mus t documen t

th e nee dfo

r suc h aseparat e limit , a s wel l a s whethe r th e selecte dvalu e represent s BART
. Ha s DENR evaluate dpotentia l impact s o f th e separat e startup/shutdow n limi t o n visibility ? Th e BAR T Guideline s contemplat e pound s pe r millio n Bt

u limit s tha

t appl y continuously , wit

h a30-da y rollin g averag e perio dt o accommodate , amon g othe r things , potentia l short-termfluctuations in th e emission s rat e that

ma y resul t durin g startup , shutdown , an dothe r conditions
. Presumably , you r

propose d30-da

y rollin g averag e limi t

already include s som e margi n o f safet y fo r operationa l variation
. I f yo u ar e abl e t o justif

y th e separat e limits , w e woul dwor k closel y wit

h yo u a s yo u draf

t appropriat e permi t

languag e t o hel p ensur e SI P approvability relate dto determinin g complianc e wit h th e normal 30-da

y rollin g averag e limi t

an dth ehourl y startup/shutdow n limit
. Fo r example , i n calculatin g 30-da y averages , ho w wil l day s b e accounte dfor

tha t includ e some , bu t

no t all , hour s o f

startup/shutdown ? 21
. Sectio n 6.4 , BAR T Requirements , p . 99 : Accordin g t o you r propose drevision s t o th e Sout h Dakot aAdministrativ e Rules , Chapte r 74:36:21:10 , apermi t

modificatio n wil l b e require dfor

you r BAR T determinatio n o n Otte r Tail' s Bi g Ston e I
. Withou t seein g th e detail s o f suc h permit , i t

i s difficul t

t o determin e whethe r

thi s sectio n o f

th e SI P adequatel y addresse s requirement s for enforceability , includin g appropriat e averagin g times , complianc e verificatio n procedures , an drecordkeepin g an dreportin g requirements , andprope r operatio n an dmaintenanc e procedures
. A s note di n commen t # 1 above , thes e requirement s mus t b e specifie deithe r

i n th e tex t

o f th e Regiona l Haz e SI P o r i n apermi t

that i s incorporate dint o th e SIP
. 22
. Sectio n 7.1 , Stat e an dFedera l Rules , pp . 100-101 : Pleas e clarif y that althoug h som e o f

th e cite dAdministrativ e Rule s o f Sout h Dakot a(ARD ) contro l emission s o f pollutant s tha t ultimatel y contribut e t o visibilit y impairment , the y wer e no t writte n specificall y t o addres s visibilit y impairment
. 23
. Tabl e 7- 1 an dSectio n 7.2.1 , BreakdouT i o f CMA Q Modelin g Results , pp . 102-103 : We were unabl e t o determin e i f

16.5 0 dv fo

r Badland s an d15.2 8 d v fo r Win dCav e ar e you r Reasonabl e Progres s Goal s (RPG)
. Thes e number s don' t quit e matc h wit

h thos e show n in Figur e 8-1
. Pleas e clarif

y an ddocumen t

ho w th e number s were obtained
. Also , th e SI P mus t includ e th e dv differenc e betwee n th e baselin e an dnatura l condition s fo r th e bes t an dwors t day s fo r th e l " plannin g perio dpe r 4 0 CF R51.308(d)(2)(iv)(A)
. Finally , th e SI P mus t provid e th e numbe r

o f year s necessary t o reac h natura l conditions , a s require dby 4 0 CFR51.308(d)(l)(ii ) whe n th e RP G i s les s than th e unifor mrat e o f progres s (URP)
. 24
. Sectio n 7.2.2 , Fou r

Facto r Analysis , p . 104 : DENR' s determinatio n that afour-facto r analysi s i s no t

warrante dat

thi s tim e i s no t

acceptable
. A four-facto r analysi s mus t

b e complete di n establishin g th e RPG s for Clas s I area s impacte dby Sout h Dakot aemissions , a s wel l a s i n justifyin g aRP G that i s les s than URP
. Whil e w e realiz e tha t th e emission s reduction s propose dunde r BAR T for

Bi g Ston e I wil l provid e significan t emission s reduction s i n South Dakota , remainin g source s mus t b e considere dunde r

Reasonabl e Progress
. Fo r

example , ar e ther e an y further reduction s that

coul db e obtaine dfrom GC C Dacotah , Be n French , o r Pet e Lien ? What

abou t potentia l impact s fromth e clos e proximity o f

Rapi dCit

y t o Badlands ? A simpl e Q/ danalysi s ca

n provid e astartin g point
. I t ma y b e reasonabl e fo

r DEN Rt o conclude , upo n completio n o f a n adequat e four-facto r analysis , that

additiona l control s unde r Reasonabl e Progres s ar e no t warrante di n thi s plannin g period
. However , suc h adeterminatio n canno t b e mad e withou t

th e analysis
. Perhap s informatio n fromth e WRAP' S Ma y 19 , 200 9 draf

l Supplementary Infonnatio n fo r Four-Facto r

Analyse s fo r

Selecte dIndividua l Facilitie s i n Sout h Dakota , an dWRAP' s Ma y 4 , 200 9 draf

t Supplementar y Informatio n fo r Fou r Facto r Analyse s by WRA

P States , ca

n b e utilize dt o addres s som e o f th e Reasonabl e Progres s analysi s requirements
. If so , our Augus t 12 , 200 9 comment s o n th e draf t WRA P report s mus t

b e take n int o account . -7 -25
. Sectio n 8.0 , Lon g Ter mStrategy , pp . 104-105 : Accordin g to 4 0 CFR51.306(c) , th e Stat e mus t revis e it s plan t o provid e fo r acoordinate dlong-termstrateg y fo r addressin g bot

h reasonabl y attributabl e an dregiona l haz e visibility impairment , an dfutur e coordinate d long-termstrategie s mus t b e submitte dconsisten t

with th e schedul e fo

r periodi c progres s report s se t

fort h in 4 0 CF R51.308(g) , i.e. , every 5 years . Sout h Dakot aneve r

adopte daplan t o addres s th e requirement s o f 4 0 CF R51.30 6 fo

r areasonabl y attributabl e visibility impairmen t

long-termstrategy ; therefore , aFedera l Implementatio n Pla n (FIP ) wa s promulgate dt o incorporat e b y referenc e th e reasonabl y attributabl e visibilit y impairmen t long-termstrateg y requirement s describe di n 4 0 CF R52.29
. Se e th e federally-approve d Sout h Dakot aIdentificatio n o f Pla n sectio n a

t 4 0 CFR52.2179(c)
. A t

tiiis time , i t

i s no t clea r fromanationa l perspectiv e ho w t o coordinat e areasonabl y attributabl e long-termstrateg y FI P with aregiona l haz e long-termstrateg y SIP
. Th e simples t approac h woul db e fo

r yo u t o develo p you r

ow n reasonabl y attributabl e long-termstrateg y t o replac e th e FIP
. I s thi s approac h somethin g yo u woul dconsider ? W e woul db e happ y t o wor k with yo u t o develo p appropriat e languag e an dbeliev e i t woul dno t

tak e to o muc h additiona l wor k give n th e effor

t yo u hav e already pu t

into th e draf

t regiona l haz e SIP
. 26
. Sectio n 8.1 , Clas s I Area s in Othe r State s Impacte db y Sout

h Dakota , p . 105 : Thi s sectio n mus t quantif y Sout h Dakota' s impac t

t o th e Clas s I area s outsid e th e Stat e (simila r t o tha t note di n Tabl e 6-4)
. 27
. Sectio n 8.3 , Technica l Basi s fo r Modeling , Monitorin g an dEmission s Information , p . 106 : T o assis t th e reader , pleas e includ e websit e addresse s and/o r reference s t o wher e thes e technica l analyse s ar e house dan dho w the y wil l b e maintaine dgoin g forward
. In addition , th e tex t mus t addres s DENR' s commitmen t t o continue dcompilatio n an danalysi s o f th e technica l requirement s fo r th e Regiona l Haz e SIP , regardles s o f futur e uncertainty in th e Weste mRegiona l Ai r

Partnership' s (WRAP's ) role
. 28
. Sectio n 8.5 , Factor s i n Developin g Lon g TermStrategy , p . 107 : Ther e appear t o b e typographical error s i n th e las t paragrap h - shoul db e "emission s reductions. " 29
. Sectio n 8.5.1 , Emissio n Reduction s fro mOngoin g Ai r Pollutio n Contro l Programs , pp . 107-108 : A s note di n commen t #2 2 above , pleas e clarif

y that althoug h som e o f

th e cite d Administrativ e Rule s o f

Sout h Dakot awer e no t

writte n specificall y t o addres s visibility impairment , the y d o contro l emission s o f pollutant s tha

t ma y ultimatel y contribut e t

o visibilit y impairment
. 30
. Sectio n 8.5.2 , Measure s t o Mitigat e Impact s o f Constructio n Activities , pp . 108-109 : Sout h Dakot aneve r

adopte daplan t o addres s th e origina l Visibility Ne w Sourc e Revie w (NSR ) requirement s o f

4 0 CFR51.307 ; therefore , aFederal Implementatio n Pla n (FIP ) wa s promulgate dto incorporat e b y referenc e th e Visibility NS Rrequirement s describe din 4 0 CF R52.28. Se e th e federally-approve dSout h Dakot aIdentificatio n o f Plan sectio n a

t 4 0 CF R52.2179(b)
. I s it you r intentio n t o replac e th e nonattainmen t NS Rvisibility analysi s requirement s o f

4 0 CFR52.2179(b ) witi i you r propose drevision s t o ARS D 74:36:21 ? If so , w e woul dprovid e inpu t

fo r suc h arevisio n i f

requested
. - 8 -31
. Sectio n 8.5.5 , Smok e Management , pp . 109-110 : Give n that you r sourc e apportionmen t analysi s identifie dorgani c carbo n mas s a s on e o f th e larges t

contributor s o n th e mos t impaire ddays , it

i s difficul t

t o understan dwhy DEN Rha s deferre dconsideratio n o f smoke managemen t

technique s unti l 2013
. In establishin g it s long-termstrategy , th e Stat e mus t conside r smok e managemen t

technique s fo

r agricultura l an dforestr

y managemen t

purpose s includin g plan s a s currenti y exis t withi n th e Stat e fo

r thes e purpose s Se e 4 0 CF R51.308(d)(3)(v)(E)
. At leas t som e preliminary steps , i n coordinatio n with th e FLMs , mus t

b e included , alon g wit h citin g t o an y existin g Sout h Dakot abumin g provisions
. 32
. Sectio n 8.5.6 , Enforceabl e Emissio n Limit s an dContro l Measures , pp . 110-111 : We not e you r intentio n t o establis h th e Bi g Ston e I BAR T limit s an dcontro l measur e requirement s in eithe r aconstructio n permi t

o r th e Title V permit
. Not e that an y ai r quality permi t

use dto addres s BAR T requirement s wil l nee dt o b e incorporate dint o th e SIP
. Th e Sout h Dakot a draf t constructio n permi t

progra mregulation s ar e currentl y unde r revie w b y ou r office
. Unti l thi s ha s bee n approve dint o th e SIP , i t wil l no t b e appropriat e t o rel y upo n th e programfo r you r BAR T permits
. 33
. Sectio n 9.0 , Monitorin g Strategy , p . 113-116 : Sout h Dakot anever

adopte daplan t o addres s th e origina l Visibilit y Monitorin g requirement s o f 4 0 CF R51.305 ; therefore , aFI P wa s promulgate dt o incorporat e b y referenc e th e Visibility Monitorin g requirement s describe di n 4 0 CFR52.26
. Se e th e federally-approve dSout h Dakot aIdentificatio n o f Pla n sectio n a

t 4 0 CF R52.2179(b)
. I s i

t you r intentio n t o replac e th e Sout h Dakot aVisibility Monitorin g FI P requirement s o f

4 0 CF R52.2179(b ) with th e DENRMonitorin g Strateg y a s outline di n Sectio n 9. 0 o f

th e Regiona l Haz e SIP ? If so , w e woul dprovid e inpu t for suc h arevisio n if requested
. 34
. Sectio n 10.2 , Consultatio n with Othe r States , pp . 118-119 : Fo r clarity , it woul db e helpfu l i f i n eac h instanc e o f

consultation , th e tex t

identifie dth e date s an doutcome s o f th e discussions
. I n addition , othe r

tha n thei r

involvemen t

i n WRAP , doe s DEN Rhav e aplan t o includ e tribal consultatio n o n th e publi c commen t versio n o f

th e SIP ? 35
. Sectio n 10.3 , Publi c Input , p . 119 : A s note di n commen t #2 3 above , th e SI P mus t

provid e th e publi c wit h acalculatio n o f th e numbe r

o f year s require dt o reac h natura l condition s i f th e RP G provide s aslowe r

rat e o f improvemen t

than tha t neede dt o attai n natural condition s b y 206 4 pe r 4 0 CF R51.308(d)(l)(ii)
. W e understan dyou r concern s regardin g assumption s fo r othe r state s include di n th e WRA P analysis ; however , thi s SI P mus t includ e you r

bes t estimat e o f

numbe r o f year s t o reac h natura l condition s with th e propose dRPGs
. 36
. Sectio n 11.2 , Report

Ever y 5 Years , p . 121 : A s par t o f continuin g consultatio n require d unde r 4 0 CF R51.308(i)(4) , pleas e clarif y ite m7 , regardin g th e monitorin g strategy , t o not e that yo u wil l consul t

wit h EP A an dth e FLM s on any revision s deeme dnecessary . 37
. Appendices : We ar e unabl e to commen t o n an y o f

th e appendice s sinc e the y were no t included
. Informatio n i

n thes e appendice s ma

y hav e bee n necessar

y for amor e thoroug h - 9

-revie w b y EPA
. If yo u ar e abl e t o shar e th e draf t appendice s prio r

to th e officia

l publi c commen t period , it woul db e very helpftil
. 38
. ARS D Chapte r

74:36:21 , Regiona l Haz e Program : (A ) 74:36:21:02 , Definitions : Th e definitio n o f "BART-eligibl e source " mus t cit e to a n existin g stationary facilit

y a s define di n 74:36:21:03
. Th e definitio n o f "visibility impairment " doe s no t

mirro r th e federal definitio n containe din 4 0 CF R51.30 1 an dmus t b e revise daccordingly
. Th e definitio n o f "contribut e t o visibility impairment " i s no t appropriat e i n th e regiona l haz e contex t an dmus t b e remove dsinc e ther e i s n o threshol dfo r suc h a contribution
. Finally , th e definitio n o f "majo r source " mus t

cit e t o 4 0 CF R51.166 , an dyo u mus t includ e th e definitio n o f

"majo r modification " fro m4 0 CF R51.166 , sinc e th e definitio n o f majo r stationary sourc e unde r

th e regiona l haz e regulation s include s majo r modifications
. (B ) 74:36:21:04 , Visibilit y Impac t Analysis : Thi s sectio n mus t b e revise dt o clarif

y tha t th e existin g provision s o f

74:36:09 , Preventio n o f

Significan t

Deterioration , ar e no t

replace db y thi s ne w sectio n 74:36:21:04
. Give n that yo u d o hav e existin g regulations , wha t i s you r inten t wit h thi s ne w provision ? (C ) 74:36:21:07 , Operatio n an dMaintenanc e o f Controls : T o improv e clarity , thi s sectio n shoul dinclud e mor e detail , suc h a s specifyin g th e minimu mcriteri afo r a n acceptabl e operatio n an dmaintenanc e plan an dwhe n th e sourc e specifi c operatio n an dmaintenanc e plan t o mee t suc h criteri ashal l b e submitte dfo r permittin g authority approval
. (D ) 74:36:21:08 , Monitoring , Recordkeepin g an dReporting : A s thi s provisio n i s drafted , th e term"mai n stack " i s aconce mbecaus e it i s no t clear whethe r al l o f th e sulfur dioxid e an d nitroge n dioxid e emission s firo mth e BART-eligibl e sourc e wil l b e route dt o th e mai n stack
. Th e ter m"mai n stack " implie s th e presenc e o f othe r stack(s ) whic h is/ar e no t

equippe dwith continuou s emissio n monitorin g system(s ) a s i s th e "mai n stack. " Th e languag e i n 74:36:21:0 8 (pag e 8 , secon dsentence ) shoul db e revise dt o read , "Al l sulfur dioxid e an d nitroge n dioxid e emission s fromth e BAR T eligibl e sourc e shal l b e route dt o th e mai n stac k o f th e BART-eligibl e source . Monitorin g o f sulfiir dioxid e an dnitroge n dioxid e emission s fromth e mai n stac k

shal l b e conducte dusin g acontinuou s emissio n monitorin g syste m whic h complie s with continuou s emissio n monitorin g syste mrequirement s i n 74:36:13. " (E ) 74:36:21:11 , Federa l Lan dManage r Notificatio n an dReview : A s require db y th e Regiona l Haz e Rule , th e Federa l Lan dManager s mus t b e provide da60-da

y consultatio n perio dprio r

to any publi c hearin g o n th e Regiona l Haz e SIP
. Sinc e aBAR T permi t i s a n integral part

o f th e Regiona l Haz e SIP , thi s 60-da y consultatio n perio dmus t exten dto FL

M BAR T permi t

revie w a s well
. In addition , sinc e an y BAR T permi t mus t b e incorporate dint o th e Regiona l Haz e SIP , th e 30-da y publi c notic e for

th e SI P need s to identif

y th e inclusio n o f an y BAR T permits
.

-10

-