p. 1



# OAR Box 1793 Prepped byKeeia Richards



### Document

Number: 

# 13) ll-F-5 5 Docket Number: 

# A-90-3 7

Printed 11/3/2008 11:31:54

AM Sheet 13 of 45P. 2

••4 

# Womuiio

nTr«,fe ran dFta^! ^ V

? PffiC C O f Ai T Qualit yPlanninT ZT* 8 

### TM 0 1 1 

### « < US Pm,_«-

_* ^^ ,|n d

### Standard s Researc hTnangl ePark , N C 2771 1 FAXNumber : (919)541-550 9

FROM : 

## 3K- 72ftC ~ NAM E" " —__ . 

### COMMENTS : IBNUHU I 

### 919>541 « Og7) 

# kst ^r e*& tint

ef ArcpeseJ

Ms;**^

£/ 29 

# .e~Arr. 

# TSTTT t II I/MJulW b 

# T^^Tiirortnnr

r Numbe r o f Page s (includin g cove r sheet) : /2 - " ^ ^ » * receiveif

l th epages , pleas econtac tth efo i flowingperson: 919.541 -P. 3

8 4 f . Ai r Qualit yChange s Certai n change s unde r th e PAL , suc ha s change s i n effectiv e stac k parameters , ca n chang e a source' s impac t area , an d mus t b e assesse d t o demonstrat e protectio n o f NAAQS , increments , an d AQRVs . Se e propose d section s 51.165(a ) (9 ) (iv ) (A ) , 51.166(u)(4)(i ) an

d 52.21(y)(4)(i) . Th e EPArequest s commen t o n whe n modelin g o r othe r ambien t impac t assessmen t shoul d b e require d fo r change s unde r a PAL , including th e usefulnes s o f existin g guidanc e o n simila r issue s (e.g. , 198 9 Federa l Registe r Notic e addressing CMA ; th e Emission s Trading Polic yStatement , us e prope r cites) , an d wha t shoul d b e don e t o protec t AQRV s i n Clas s I areas . G . Actual-to-future-actua l Methodolog y A s previousl ydiscussed , th e EPAexplicitl ylimite d th e scop e o f th e WEPC O rulemaking t o on e sourc e category—electri c utilit ystea

mgenerating units . I n th e fina l rule , however , th e EPAindicate d tha t i t woul d "conside r th e desirabilit yo f adoptin g fo r othe r sourc e categorie s th e . . . change s t o th e methodologyfo r determining whethe r a sourc e chang e constitute s a modification " i n a subsequen t rulemaking . 5 7 FR 32333 . I n previou s sections , th e EPAdiscusse s it s proposal s t o adop t a ne w pollutio n contro l projec t exclusio n applicabl e t o al l sourc e categorie s an

d t o replac e it s existing baselin e regulation s wit h a ne wprovision , agai n applicabl e t o al l sourc e categories . PRELIMINAR

YSTAFF WORKIN

GDRAFT FO

ROFFIC E O

F MANAGEMEN

T AN D BUDGE T REVIE

W * DOE S NOT REPRESEN T OFFICIA

L EP A POLICY ***Octobe r 20 , 199 5 [fil e name : Master9.17 ] ** *P. 4

8 5 Ther e remains.th e questio n o f th e "future-actual " methodology whic hallow s a utilit yt o us e a predictio n o f it s post-chang e actua l emission s —excluding an yincrease s i n utilizatio n cause d b ydemand growt h—

t o determin e whethe r th e chang e a t issu e wil l increas e emission s ove r actua l baselin e levels . Th e WEPC O rul e wa s challenge d b ybot hindustryand environmenta l petitioners . Thes e challenge s include d a demand fromsome industrie s tha t EPAexpand th e WEPC O rul e t o al l sourc e categorie s and a demand froma n environmenta l group tha t EPA abando n th e rul e o r a t leas t th e demand growt hexclusion . Thi s litigatio n i s no winactiv e pendin g th e outcome o f thi s rulemaking . Fo r thi s reaso n Today , EPAsolicit s oommcnt o o n thre e altornativo a fo r propose s t o allo wus e o f th e future-actua l methodologyfo r al l sourc e categories * A s discusse d i n sectio n II.A. , EP Apropose s tha t State s b e give n th e choic e o f whethe r t o 

### 0 retai n i n thei r SIP s th e curren t actual-to-potentia l test , o r t o - , adop t th e actual-to-actua l tes t fo r al l sourc e categories . * f «|/( 1 Althoug hEP Ai s als o proposin g th e actual-to-futur e actua l tes t fo r th e Federa l permittin g programi n lie u o f th e curren t actual

to-potentia l test , EP Asolicit s comment s o n whethe r t o retai n th e actual-to-potentia l test.n—(i f I n addition , EP Asolicit s comment s H i leaving -art

e th e scop e o f th e futur e actua l methodologyth e same —availabl e onl yfo r utilit yunits-;—(-2-)—extendin g th o futuro-aotua l mothodologyt o al l sourc e categories ; o r -(-3-)

- PRELIMINARY STAF F WORKIN GDRAF T FOR OFFIC E O F MANAGEMENT AND BUDGE T REVIE W* DOE S NO T REPRESENT OFFICIAL EPAPOLIC Y ***Octobe r 20 , 199 5 [fil e name : Masters.17 ] ** *P. 5

8 6 eliminatin g th e methodologycompletely. 2 4 I n addition , i f optio n l o r 2 . i o oolootodi n regar d t o us e o f a futur e actua l ||iii||ii!;|iii|| , th e EPAsolicit s commen t o n wha t change s i f an yr^ v| L shoul d b e mad e t o th e demand growt hexclusio n an d th e fiv e yea r trackin g requirement . Se ©propose d 52.21(b)(21)(vi) t 51.166(b)(21)(Vi ) an d 51.165(a)(1)(xii)(F) * 1 . Background A s noted , th e WEPC O rul e create d prescribe d i n EPA' s regulation s a ne wmethodologyfo r determinin g whethe r a physica l o r operationa l chang e woul d resul t i n a significan t increas e i n emission s an

d therefor e constitut e a majo r modification . Th e rul e provide d tha t th e post-chang e emission s leve l o f a utilit y uni t woul d b e calculate d using a projectio n o f th e unit' s "future-actual " emissions . Th e rul e wa s limite d t o existin g electri c utilit ystea mgenerating unit s an d di d no t appl yt o th e additio n o f a ne wuni t o r th e replacemen t o f a n existin g unit. 2 5

2 4 Thi s discussio n o f th e us e o f th e future-actua l methodologya s a n applicabilit ytes t i s separat e fromth e propose d us e o f th e methodologyt o projec t emissio n increase s frompollutio n contro l project s i n sectio n II.E .

2 5 Auni t i s considere d replace d i f i t woul d constitut e a reconstructe d uni t withi n th e meanin g o f 4 0 CF R 60.1 5 (the NSP S tes t fo r "reconstruction") . EPAreasone d tha t sinc e ther e i s n o relevan t operating historyfo r wholl yne wunit s an d replace d units , i t i s no t possibl e t o reasonabl yprojec t post-chang e utilizatio n fo r thes e units , an d hence , thei r futur e leve l o f "representativ e annua l emissions. " Fo r othe r changes , pas t operatin g historyan d othe r relevan t informatio n provide s a basi s fo r reasonabl e projections . Se e 5 7 FR 32323 . PRELIMINARY STAF F WORKINGDRAF T FOR OFFIC E O F MANAGEMENT AND BUDGE T REVIE W* DOE S NO T REPRESENT OFFICIAL EPAPOLIC Y •••Octobe r 20 , 199 5 [fil e name : Master9.17 ] •• •P. 6

8 7 Pursuant-t o th e WEPC O rule , th e future-actua l projectio n i s th e produc t o f (1 ) th e hourl yemission s rate , whic hi s base d o n th e unit' s physica l and operationa l capabilitie s following th e chang e and takin g int o accoun t federall yenforceabl e operationa l restriction s tha t woul d affec t th e hourl yemission s rat e followin g th e change ; an d (2 ) projecte d capacit yutilization , whic hi s base d o n (a ) th e unit' s historica l annua l utilization , and (b ) al l availabl e informatio n regarding th e unit' s likel y post-chang e capacit yutilization . Se e 5 7 FR 32323. 2 6 T o guar d agains t th e possibilit ytha t significan t unreviewe d increase s i n actua l emission s woul d occu r unde r thi s methodology , th e EPA provide d i n it s fina l regulation s tha t an yutilit ywhic huse s th e "representativ e actua l annua l emissions " methodologyt o determin e tha t i t i s no t subjec t t o NS R mus t submi t annuall yfo r 5 year s afte r th e chang e sufficien t record s t o demonstrat e tha t th e chang e ha s no t resulte d i n a n emission s increas e ove r th e baselin e levels . Se e 5 7 FR 32325 . T o mee t thi s requirement , utilitie s ca n us e continuou s emission s monitorin g data , operationa l levels , fue l usag e data , sourc e tes t results , o r an y othe r readil yavailabl e dat a o f sufficien t accurac yfo r th e purpos e o f documentin g a unit' s post-chang e actua l annua l

2 6 I n projectin g futur e utilizatio n an d emission s factors , th e permittin g authorit ymayconside r th e company' s historica l operationa l data , it s ow n representations , filing s wit hFederal , Stat e o r loca l regulatoryauthorities , an d complianc e plan s develope d unde r titl e V o f th e Act . Se e 5 7 FR a t 32323 , n . 19 . PRELIMINAR

YSTAFF WORKIN

GDRAF T FO

ROFFIC E O

F MANAGEMEN

T AN D BUDGE T REVIE

W * DOE S NO T REPRESEN T OFFICIA

L EP A POLICY •••Octobe r 20 , 199 5 [fil e name : Master?.17 ] ** *P. 7

8 8 emissions . Wher e th e chang e doe s no t increas e th e unit' s emission s factor , th e utilit ymaysubmi t annua l utilizatio n data , rathe r tha n emission s data , a s a metho d o f trackin g post-chang e emissions . Id . I f durin g th e 5 year s th e unit' s post-chang e actua l emission s excee d it s pre-chang e baselin e level , i t i s the n subjec t t o NSR . Increase s whic hoccu r afte r th e 5 year s ar e presume d no t t o b e relate d t o th e earlie r change. 2 7 A s discussed , th e NS R regulatoryprovision s requir e tha t th e physica l o r operationa l chang e "resul t in " a n increas e i n actua l emission s i n orde r t o conside r tha t chang e t o b e a modification . Se e als o th e discussio n o f term""modification " i n Sectio n I I «B . <r\Qg o f thi s notice * I n other*''words , HS R wil l no t appl yunles s ther e / ^f i s a causa l link betwee n th e propose d chang e and anypost-chang e \UA^ increas e i n emissions * I n th e WEPC O rule , EP Aclarifie d thi s provisio n i hth e contex t o f modification s a t electri c utilit y generatin g unit s t o exclud e increase s du e t o EPAaddcd ma oauoatio n requiremen t languag e t o implemen t thi a principl e tha t focuse d o n a n "independen t factor! " tha t coul d cauo c inorcaoc o fo r utilities t suc ha s demand growth . Th e EPAstate d that :

"...wher e projecte d increase d operation s ar e i n s respons e t o a n independen t factor , suc ha s demand T)0ly growth , whic hwoul d hav e occurre d an d affecte d th e j facA unit' s operation s durin g th e representativ e baselin e '

2 7 Th e permittin g authorit ymayrequir e a longe r period , no t t o excee d 1 0 years , wher e i t determine s tha t n o perio d withi n th e firs t fiv e year s following th e chang e i s representativ e o f norma l sourc e operations . 5 7 FR 32325 . PRELIMINARY STAF F WORKINGDRAF T FOR OFFIC E O F MANAGEMENT AND BUDGE T REVIE W* DOE S NO T REPRESENT OFFICIAL EPAPOLIC Y •••Octobe r 20 , 199 5 [fil e name : Master9.17 ] ** •_R__ _

8 9 perio d eve n i n th e absenc e o f th e physica l o r operatinona l change , th e increase d operation s canno t b e sai d t o resul t fromth e chang e an d therefor e mayb e exclude d from

th e projectio n o f th e unit' s futur e actua l emissions . Conversely , wher e th e increas e coul d hav e occurre d during th e representativ e baseliln e perio d bu t fo r th e physica l o r operationa l change , tha t chang e wil l b e deeme d t o hav e resulte d i n th e increase . Thus , thi o th e promulgate d regulatoryprovisio n exclude d fromth e calculatio n o f futur e emissions :

tha t portio n o f th e unit' s emission s following th e chang e tha t coul d hav e bee n accommodate d durin g th e representativ e baselin e perio d an d i s attributabl e t o a n increas e i n projecte d capacit yutilizatio n a t th e uni t tha t i s unrelate d t o th e particula r change , including an

yincrease d utilizatio n du e t o th e rat e o f electricit ydemand growt hfo r th e utilit ysystema s a whole . See , e.g. . existing 51.166(b)(32)(ii) . Th e EPAexplaine d tha t thi s provisio n allow s demand growt h t o b e exclude d fromth e calculatio n o f futur e emission s onl y"t o ^
. 

### (oW- J/ ' th e exten t i t —an d no t th e physica l o r operationa l chang e —i s th e caus e o f th e emission s increase. " 5 7 FR 32327 . O n th e othe r hand , an

yemission s increase s attributabl e t o a physica l o r operationa l chang e tha t "significantl yalter s th e efficienc yo f th e plan t . . . mus t b e include d i n th e post-chang e emission s calculations. " 5 7 F R 32327 . Thus , th e questio n o f exclusio n o f independen t factors , suc ha s system-wid e demand growth , i s " a questio n o f fac t whic hmus t b e resolve d o n a case-by-cas e basi s an d i s dependen t o n th e individua l fact s an d circumstance s o f th e chang e a t issue. " Id . PRELIMINARY STAF F WORKINGDRAF T FOR OFFIC E O F MANAGEMENT AND BUDGE T REVIE W* DOE S NO T REPRESENT OFFICIAL EPAPOLIC Y •••Octobe r 20 , 199 5 -- - [fil e name : Master9.17 ] ** *P. 9

9 0 2 . Limitatio n o f th e WEPC O Rul e t o On e Sourc e Category Th e EPAindicate d i n th e WEPC O rul e tha t i t ha d "high confidence " tha t a workabl e "future-actual " methodologycoul d b e develope d fo r th e utilit yindustryfo r al l change s tha t di d no t involv e constructio n o f a ne wuni t o r th e replacemen t o f a n existin g unit . 5 7 FR 32333 . Specifically , th e EPApointe d t o severa l factor s including (1 ) a limite d an d technologicall y homogeneou s sourc e population ; (2 ) oversigh t b yStat e Publi c Utilit yCommission s tha t typicall yevaluat e utilit ygrowt han d utilizatio n projections ; an d (3 ) requirement s i n titl e I V o f th e Ac t tha t mandat e continuou s emission s monitor s (CEMs ) o r othe r highl yaccurat e method s fo r recording actua l emission s a s wel l a s specia l reportin g requirements . I n EPA' s judgment , thes e factor s mean t tha t permittin g authoritie s coul d mak e independen t assessment s o f th e likel ypost-chang e emission s an d utilizatio n rate s o f utilit yemission s units , an d coul d trac k thes e prediction s fo r th e relevan t perio d t o ensur e tha t th e utilit y di d no t excee d it s predicte d leve l o f emissions . Th e EPAcontinue s t o vie wthes e characterization s a s generall yaccurate . Ther e ar e a relativel ylimite d numbe r o f electri c utilit yinstallation s and , du e t o titl e I V an d othe r regulatoryprograms , th e EPAan d stat e an

d loca l permittin g authoritie s hav e extensiv e informatio n o n th e type , fuel , size , an d othe r characteristic s o f th e electri c generatin g unit s i n PRELIMINAR

YSTAFF WORKIN

GDRAF T FO

ROFFIC E O

F MANAGEMEN

T AN D BUDGE T REVIE

W * DOE S NO T REPRESEN T OFFICIA

L EP A POLICY •••Octobe r 20 , 199 5 [fil e name : Master9.17 ] •* •P.1 0



# If 9 1 operation . Mos t o f th e utilitie s operating thes e unit s ar e subjec t t o regulatoryoversigh t b ya Stat e Publi c Utilit y Commissio n (PUC ) whic hregularl yrevie wgrowt hpattern s an d utilit ystrategie s fo r meetin g futur e electrica l demand . Finally , a s a resul t o f titl e IV , mos t larg e utilit yunit s ar e now , o r wil l b e shortly , usin g CEM s t o demonstrat e continuou s complianc e wit hman yo f th e federa l an d Stat e requirement s applicabl e t o thei r units . Similarly , th e EPAexpect s tha t mos t majo r source s i n th e countrywil l b e upgrading thei r monitorin g an d reportin g capabilitie s du e t o th e Act' s monitorin g an d titl e V operatin g permi t programs . Thes e source s shoul d thu s als o b e abl e t o provid e th e necessarydocumentatio n o f thei r complianc e wit ha post-chang e emission s prediction . However , utilitie s remai n th e onl ysourc e categorywher e projection s o f demand an d facilit yutilizatio n ar e typicall y assesse d b

ya n independen t regulatoryagency , th e Stat e PUC , an d ii| i availabl e t o th e public . Becaus e o f this , permittin g authoritie s shoul d b e abl e t o fin d independen t dat a an d assessment s regardin g curren t operation s an d cost s fo r th e utilit yuni t subjec t t o th e chang e a s wel l a s projecte d dat a fo r th e uni t afte r th e change . Similarly , th e PU C shoul d hav e mad e a n assessmen t o f futur e demand growt han d utilit yplan s t o mee t thi s increase d demand s o a permitting authorit yshoul d b e abl e t o secur e independen t corroboratio n o f utilit yclaim s i n thi s are a
PRELIMINARY STAF F WORKIN GDRAF T FOR OFFIC E O F MANAGEMENT AND BUDGE T REVIE W• DOE S NO T REPRESENT OFFICIAL EPAPOLIC Y •••Octobe r 20 , 199 5 [fil e name : Master9.17 ] *• *P.1 1

9 2 a s well . Becaus e thi s kind o f informatio n i s typicall yno t availabl e fo r othe r sourc e categories , th e EPAi s concerne d abou t th e basi s permittin g authoritie s woul d hav e t o revie wprojection s fo r othe r sourc e categories . O n th e othe r hand , th e five-yea r tracking provisio n tha t wa s adopte d i n th e fina l WEPC O rul e make s th e accurac yo f th e futur e projectio n subjec t t o a safeguar d tha t shoul d guarante e th e accurac yo f th e predictio n fo r a t leas t fiv e years . Thi s trackin g perio d mayb e extende d t o 1 0 year s wher e th e permittin g authorit yi s concerne d tha t th e firs t fiv e year s wil l no t b e representativ e o f norma l sourc e operations . See , e.g. . existin g sectio n 51.166(b)(21)(v) . Eve n afte r thi s tim e period , th e permittin g authorit ymaystil l conside r whethe r a n increas e tha t occur s i s "caused " b yth e chang e an

d thu s result s i n a n emission s increas e subjectin g th e origina l chang e t o majo r NSR . Se e 5 7 FR 32326 . Therefore,I n proposin g t o expand future-actua l methodologyt o al l sourc e categories , th e EPAals o solicit s commen t o n th e adequac yo f thes e safeguard s an d whethe r th e future-actua l methodologyshoul d b e (1 ) retaine d onl yfo r th e electri c utilities , expande d t o al l oouro o oatogoric o o r ;||| f eliminate d entirely . 3 . Issue s Regarding Th e Future-Actua l Methodology Th a EPAalo o seek s commen t o n tw o additiona l specifi c part s o f th e WEPC O rule . First , th e EPAsolicit s commen t o n whethe r a
PRELIMINARY STAF F WORKINGDRAF T FOR OFFIC E O F MANAGEMENT AND BUDGE T REVIE W• DOE S NO T REPRESENT OFFICIAL EP APOLIC Y •••Octobe r 20 , 199 5 [fil e name : Master9.17 ] ** *P.1 2

9 3 demand growt hexclusio n shoul d b e included , wit ho r withou t changes-TJ ! i f EPAadopt s a n aotual-to-future-actua l methodology fo r gome o r al l oouro o categories * Second , th e EPAsolicit s commen t o n whethe r th e 5 yea r reporting provisio n i s workin g a s intende d and whethe r i t shoul d b e change d i n an yway . A s discussed , th e WEPC O rul e require s th e permittin g authorit yt o exclud e fromth e post-chang e emission s estimate , an y increas e i n utilizatio n tha t i s unrelate d t o th e particula r change , "including an yincrease d utilizatio n du e t o th e rat e o f electricit ydemand growt hfo r th e utilit ysystema s a whole. " Whil e thi s provisio n "doe s no t amoun t t o a pe r s e exclusio n o f demand growt hfromth e emission s increas e calculation " (5 7 F R 32327) , i t maycreat e confusio n outsid e th e utilit yare a a s t o whe n demand growt hincrease s mayb e excluded . Th e WEPC O preambl e i s veryclea r tha t an yincrease s a t a uni t tha t resul t froma chang e tha t significantl yaffect s th e efficienc yo f th e uni t mus t b e include d i n th e future-actua l calculation , althoughEPAdecline d t o creat ©a presumptio n tha t ^fi ever yemission s increas e tha t follow s a chang©i n efficienc y(a t ) f» 5 a n utilit y©lectri c generatin g unit ) i s inextricabl ylinke d t o th e efficienc ychange . Id . Indeed , wher e th e propose d chang e wil l increas e reliability , lowe r operating costs , o r improv e othe r operationa l characteristic s o f th e unit , increase s i n utilizatio n tha t ar e projecte d t o follo wca n an d shoul d b e
PRELIMINARY STAF F WORKINGDRAF T FOR OFFIC E O F MANAGEMENT AND BUDGE T REVIE W* DOE S NO T REPRESENT OFFICIAL EP APOLIC Y •••Octobe r 20 , 199 5 [fil e name : Master9.17 ] ** *P.1 3

9 4 attributabl e .t o th e change . Thes e factor s ar e th e veryfactor s tha t utilitie s us e t o orde r th e productio n dispatc ho f th e variou s unit s i n th e system . Th e EP Abelieve s tha t thi s approac h Am, ha s prove n t o b e effectiv e i n distinguishin g demand growt hfo r ®, «« / utilitie s frf o & vi s othe r factor s tha t resul t i n loa d shifting)
. Commen t i s requeste d o n th e experienc e t o dat e wit hth e us e o f th e WEPC O deman d growt hexclusion . Moreover , i t i s clea r fo r othe r sourc e categorie s tha t prediction s o f futur e demand an d it s impac t o n individua l emission s unit s ar e fa r mor e complicate d an d chaotic . Fo r consumer-drive n industries , fo r instance , demand varie s an d presumption s regarding it s siz e an d sourc e woul d b e *£H? mor e speculativ e tha n i n th e utilit yindustry . I n mos t industries , i n othe r words , th e predictio n o f future-actua l emission s slfhould b e lef t t o th e permittin g authorit yfo r a case-by-cas e determinatio n o f whethe r th e propose d chang e wil l caus e an yincreas e i n emission s o r whethe r al l o r par t o f an yprojecte d increase s wil l b e cause d b

yindependen t factors . Fo r thi s reason , EPAseek s specifi c comment s o n th o nee d fo r wlliliel i th e demand growt h exclusio n no t onl ywithini bu t ala o outoid o th e utilit yinduotryp '•J l shoul d b e •(! > expande d t o al l sourc e categorie s (2 ) retaine d onl y fo r th e electri c utilit ysector , o r (3 ) eliminate d fo r al l industries .

PRELIMINARY STAF F WORKINGDRAF T FO R OFFIC E O F MANAGEMENT AND BUDGE T REVIE W* DOE S NO T REPRESENT OFFICIAL EPAPOLIC Y •••Octobe r 20 , 199 5 [fil e name : Master9.17 ] ** *P.1 4

9 5 I n addition , th e EPAsolicit s commen t o n th e fiv e yea r trackin g requiremen t whic hmandate s tha t permittin g authoritie s trac k future-actua l projection s fo r fiv e year s following th e a chang e t o insur e thei r accuracy . Her o Th e EPAbelieve s tha t thea/*iM 2 mechanis m

i s workin g a s intended . However , th e EPAinvite s th e publi c t o commen t o n thi s issu e an d th e experienc e t o dat e o f applicabilit ydetermination s makin g us e o f thi s safeguard . H . Proposa l o f CM A Exhibi t B A s par t o f th e settlemen t o f a challeng e t o th e EPA' s 198 0 NS R regulation s b

yChemica l Manufacturer s Associatio n (CMA ) an d othe r industrypetitioners , th e EPAagree d t o propos e fo r publi c commen t an

d tak e fina l actio n o n a methodologyfo r determinin g whethe r a sourc e ha s undertake n a modificatio n base d o n a source' s potentia l emissions . Th e exac t regulatorylanguag e th e EPAwa s t o propos e wa s se t fort hi n Exhibi t B t o th e Settlemen t Agreemen t whic hi s containe d i n th e docke t fo r thi s rulemaking . Unde r thi s methodology , source s maycalculat e emission s increase s an d decrease s base d o n eithe r th e actua l emission s methodologyi n th e existin g rule s o r th e unit' s potentia l emissions , measure d i n term s o f hourl yemission s (i.e. , pound s o f pollutan t pe r hour) . Source s coul d us e thi s potential-to-potentia l tes t fo r bot hNS R applicabilit yand fo r calculating offsets , nettin g credit s and othe r emission s reduction s credits .

PRELIMINAR

YSTAFF WORKIN

GDRAF T FO

ROFFICE O

F MANAGEMEN

T AN D BUDGE T REVIE

W * DOE S NOT REPRESEN T OFFICIA

L EP A POLICY •••Octobe r 20 , 199 5 [fil e name : Master9.17 ] ** *