## STAT E O F UTA H

MICHAELO
. LEAVIT T OFFIC E O F TH E GOVERNO R OLEN E S
. WALKE R

GOVERNO R SAL T LAK E CIT Y LIEUTENAN T GOVERNO R £ 4 1 14-060 1

Jul y 3 , 2002 Rober t E . Robert s Regional Administrato r EP A Regio n VII I 99 9 18t h Stree t - Suit e 50 0 Denver , Colorad o 80202-240 5 Dea r Mr . Roberts : Re : PM1 0 SI P Revisio n - Uta h Count y O n Jul y 3 , 2002 , th

e Uta h Ai r Qualit y Boardapprovedarevisio n t o th e Stat e Implementatio n Plan (SIP ) fo r PM1 0 i n Uta

h County . A t

th e conclusio n o f

th e State' s administrativ e process , th e revisio n wil l becom e Stat e law . The effectiv e dat

e wil l b e Septembe

r 1 , 2002 . The primar

y objectiv e o f

thi s SI P revisio n was t

o facilitat e apositiv e finding o f transportation conformit y i n Uta h County . Recognizin g tha t such findin g must

b e base do n afederall y approvedSIP , we hav e worke dextensivel y wit h your staff , an dno w request

tha t thi s submitta

l b e processeda

s expeditiousl y a

s possible . Enclosed , ar

e tw o copie s o f

eac h o f th e following : 1 ) Uta

h Stat e Implementation Plan Sectio n I X Par t A , Fin e Particulate Matter (PM10) , Uta

h County ; 2 ) revision s t

o Uta h Stat e Implementation Plan Sectio n I X Par t H . 1 , Emissio n Limits , Uta h County ; an

d3 ) Supplemen

t 11-0 2 t o th e Technical Suppor

t Documen

t fo r th e PM1 0 SIP . Pleas e contact

Ric k Sprott , Director , Divisio n o f Ai r Quality , a

t 801-536-0072 , regardin g further informatio n o

r question s concernin g thi s submittal . Sincerely .
Michae l O . Leavit

t Governor MOL:DRN:dc o cc : Ric k

Sprot tIX.A. 7 MAINTENANC E

Wit h thi s revisio n t o th e PM 1 0SIP , th e Uta h Ai rQualityBoar d commit s t o developin g a PM 1 ( maintenanc e pla n o rSI P revision , a s appropriate , base d o n dispersio n modeling
. IX.A. 8 CONTINGENC Y MEASURE S IX.A.8.a
. Attainmen t Dat e O n 1 8 Jun e 2001 , EP Apublishe d a findin g (6 6 F R 32752 ) tha t Sal t Lak e Countyha d attaine d th e NAAQ S b

y3 1 Decembe r199 5 an d Uta h Countyha d attaine d th e NAAQ S b y 3 1 Decembe r1996
. That notic e als o state d tha t bot h area s ha d demonstrate d Reasonabl e Furthe rProgres s a s require d i n th e Act (6 6 F R 32752-754)
. A lette rfro m EP ARegio n VII I t o th e Divisio n o

f Ai rQualitydate d Octobe r6 , 200 0 state d that , "I n a n Octobe r6 , 199 5 memorandu m fro m Jo e Paisi e o f OAQP S t o th e EP Aregiona l offices , it wa s explaine d tha t if a PM 1 0nonattainmen t are a ha s attaine d th e standar d wit h a t leas t 3 years o

f clea n ai r qualit ydata , an d a s lon g a s tha t are a continue s t o attai n th e standard , th e sectio n 172(c)(9 ) contingenc

ymeasur e requiremen t wil l no t apply. " Therefore , wit h eigh t year s o f clea n ai rqualit

ydata , Uta h i s no

t require d t o submi t contingenc ymeasure s i n thi s SIP
. Copie s o f th e Jo e Paisi e memorandu m an d th e Octobe r6 , 200 0 lette rfro m EP At o UDA Q are containe d i n Supplemen t II-0 2 o f th e TSD
. 

### IX.A. 9 ANNUA

L AVERAG

E DEMONSTRATIO

NO F ATTAINMEN

T O F TH E ANNUA

L AVERAG E Th e applicatio n o

f man yo f th e contro l strategie s tha t are bein g implemente d to reduc e th e 24-hou rPM 1 0concentration s wil l als o resul t i n a reductio n o f th e annua l PM 1 0 concentration s eve n thoug h the yare designe d t o reduc e winte rtim e 24-hou r concentrations
. Tabl e 9.A.2 6 show s tha t th e winte rseaso n i s th e perio d tha t ha s th e greates t impac

t o n th e annua l averag e an d controllin g PM 1 0concentration s durin g th e winte rwil l have th e greates t impac t o n th e annua l average . Desig n value s i n Uta h Countyrange d fro m 19 1 //g/m 3 t o 26 4 /vg/m 3
. Thus , th e contro l strateg ynecessar yt o achiev e th e 24-h rNAAQ S at al l station s effectivel yrange s fro m 27 % to 43%
. Eve n th e minimu m o f thi s rang e i s wel l i n exces s o f th e 7.4 % necessar

y to brin g th e maximu m observe d annua l concentratio n bac k dow n t o th e leve l o

f th e annua l standard
. Th e annua l NAAQ S fo rPM 1 0wa s neve rviolate d i n Uta h County
.

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