Office of Transportation EP A420-B-04-012 and Air Quality July 2004 

# Companion Guidance for the July 1, 2004, Final Transportation Conformity Rule 

# Conformity Implementation in Multi-Jurisdictional Nonattainment and Maintenance Areas for Existing and New Air Quality StandardsEPA420-B-04-012 July 2004



## Companion Guidance for the July 1, 2004, Final Transportation Conformity Rule Conformity Implementation in Multi-Jurisdictional Nonattainment and Maintenance Areas for Existing and New Air Quality Standards

Transportation and Regional Programs Division Office of Transportation and Air Quality U.S. Environmental Protection Agencypage 1

[sig ne d b y Suzan ne R udzi nski on July 21, 2004]

MEMO RANDUM : From: S uzan ne Rudzi nski, Di r ect or Transp ortationand Regi on al Pr og rams Divisi on Of fi ce o f Tr an sportation and A irQuality To : E PA Reg ional Ai r D i re ctors, Regions I - X Sub j ect : Comp anion Gui d ance f or th e J uly 1, 2004, Final Tr an sportation Conformity Rule: Conformity I mplementation in Mu lti-jurisd ic tional Nonatta inme nt and Ma in tenance Ar eas for Existing and New A irQuality St andar ds Pa rt 1: Intr oduct i on 1. Q. Wh at is th e purpo se of this guidance? A. Th e E nvironmen tal Prot ect ion Ag ency (EPA) pub lishe d a f inal tr an sportation co nformity rule for th e n e w ai rquality st andar ds on July 1, 2004 (69 F R 40004) 1

. Th e fin a l ru le describes in genera l t erms how conformity will a ppl y t o new nonatta inme nt and maintenan ce areas under th e 8- ho ur ozon e and P M 2.5 standards, and ho wnonattainme nt areas fo r the 8-hour ozone standard w ill u se ex is ting adequate or approved mo tor vehicle em issions b udget s (“b udget s ”) in st ate i mplement at ion plan s (SIPs) prepared f or th e 1- ho ur ozon e s t andar d. Th e t r an sportation co nformity rule ( 40 C FR part 93) outlin es the pr o cedures fordet ermining whet her fe der ally fund ed o rappr ov ed hi ghway and t r an sit pr oj ect s are co nsistent wi th (“ co nform” to) st ate ai rquality goal s. Bo th EPA and t h e U. S. Department of Tr an sp ortation ( DOT ) agree i t is n eces sary to pr ovid e addi tion al guidance f orco nformity implement at ion to acco mp an y th e f inal rule. EPA is is su ing this guidance to clar ify h ow conformity d etermin at io ns and the regional

1 This final rule was si gned o n June 14, 2004, and was avai labl e as of th at dat e, before the ef

f ect iv e dat e of th e 8- ho ur ozon e des i gnat ions. Howev er, EPA uses the Fe der a l R e gis ter pub li cat ion dat e when referring to a rule, so th at r eader s kn ow in which Fe der a l R e gis ter i ssu e to find it.page 2

em issions anal ys es th at s uppo rt th em are co mp lete d i n

ex isting and n e w n onattainment an d maintenan ce areas , partic ular ly thos e where m ultiple agencies or st ates are i nvolv ed. This guidance co vers ques tions su ch as :

< Wh at geo gra phic area i s co vere d b y th e co nformity det ermin at ion and r e gi on al emi ssi on s analysis?
< How can th e r e gi on al em issions anal ysis be implement ed?
< Who does what to dev elo p t h e r e gi on al em issions anal ysis?
< Wh at re gi on al em issions test or tests appl y for8- ho ur ozon e n onattainment areas with 1-hour ozone SIP budgets? This guidance co vers both ex isting nonattainment and maintenan ce areas as well as areas th at are des i gnated n onattainment under th e n e w s t andar d s, and hi gh lights o ppo rt unities fo rfle x ibility wherever possible. It prov id es examples and in terpretations fo r generic s cenar ios th at are presen t in th e f i eld and t h at are expected t o o ccur under th e n ew st andar ds. It expan ds on th e J uly 1, 2004, final rule by in cludi ng addi tion al det ail, examples , and pict orial re presen tations. Howev er, th ere may be othercases in th e f i el d th at this guidance does not addres s. In th e even t an area’ s ci rc um st ances are n ot co vered in

this guidance, EPA, together with DOT, w ill w ork with impleme nters on a case-by-case ba sis. This guidance al so stresses th e i mp ortan ce o f th e i ntera gen cy co ns ul tation in the co nformity pr o ces s. Gi ven th e fact th at no two areas th at implement co nformity ar e exact ly alik e, th e i ntera gen cy co ns ul tation pr o ces s can be used t o make t h e b est ch oi ces fo r an area’s circumstances, where the ru le prov id es fle x ibility. The in teragency co ns ul tation pr ovision of th e co nformity rule, §93.105, re qui res th at gen eral pr oc es ses be es tablishe d f or, and s p eci fi c deci sions be ma de t hro ugh , intera gen cy co ns ul tation. DOT, ourfe dera l p artnerin deve lo ping and impleme nt ing the conformity ru le , assisted in th e dev elo pmen t of this guidance and co nc urre d o n its co nt en t. 2. Q. Who can an sw er ques tions relate d t o this guidance? A. For sp eci fi c ques tions ab out ci rc um st ances in partic ular nonattainment or maintenance areas , th e E PA Regi on al Of fi ces , th e F HWA Di vision Of fi ces , and t h e F TA Regi on al Of fi ces are t h e f irst po int of co nt act . A list of EPA Regi on al co nformity st af f can be fo un d on th e web at : http ://www.epa.go v/ot aq/t rans p/co nform/ co nt act s.htm

. Gen eral ques tions ab out this guidance can be di r ected t o La ura Berry, a memb er of my st af f at EPA’s Of fi ce o f Tr an sportation and A irQuality, vi a h eremai l addres s: be rry.l aura @epa .g ov orph on e n umb er: 734-214-4858.page 3 3. Q. Does this guidance create new conformity requirements? A. No. This guidance is based on conformity implementation precedent to date and the July 1, 2004, final rule. This document provides guidance to EPA Regional Offices, FHWA Divisional Offices, FTA Regional Offices, state and local agencies, and the general public on how EPA intends to exercise its discretion in implementing the statutory and regulatory provisions for determining conformity in multi-jurisdictional areas. The guidance is designed to clarify and transmit national policy on these issues. The statutory provisions and EPA regulations described in this document contain legally binding requirements. This document does not substitute for those provisions or regulations, nor is it a regulation itself. Thus, it does not impose legally binding requirements on EPA, states, or the regulated community, and may not apply to a particular situation based upon the circumstances. This guidance is based on conformity precedent and interpretations made to date. EPA is issuing this guidance so that the precedents are gathered in one place as a reference forconformity implementers. EPA retains the discretion to adopt approaches on a case-bycase basis that may differ from this guidance, but still comply with the statute and conformity regulations. Any decisions regarding a particular conformity determination will be made based on the statute and regulations. This guidance is a living document and may be revised periodically without public notice. 4. Q. What do we mean by multi-jurisdictional nonattainment and maintenance areas? A. To answer this question, first it is useful to describe a conformity determination in the case where there is a single jurisdiction responsible for transportation planning, and a single jurisdiction responsible for air quality planning. In the simplest case, a nonattainment or maintenance area is located entirely within one state, and the boundary of the nonattainment/maintenance area is exactly the same as the metropolitan planning organization (MPO) boundary, as in Figure 1 below.page 4 The MPO is the agency that is responsible for preparing metropolitan transportation plans (“plans”) and transportation improvement programs (TIPs) and demonstrating that plans and TIPs conform before they are adopted. An MPO is established for each metropolitan area that has an urbanized population of 50,000 or more according to Section 134 of Title 23, United States Code and Section 5303 of Title 49, United States Code. Section 93.101 of the conformity rule includes the following definition of an MPO: “that organization designated as being responsible, together with the state, for conducting the continuing, cooperative, and comprehensive planning process under 23 U.S.C. 134 and 49 U.S.C. 5303. It is the forum for cooperative transportation decision-making.” In most cases, a conformity determination for a transportation plan, TIP, or project not from a plan or TIP includes a regional emissions analysis in which emissions from the planned transportation system are estimated according to §93.122 of the conformity rule. In the case where an MPO’s boundaries are the same as the nonattainment (or maintenance) area’s boundaries, the MPO is responsible for the regional emission analysis in the entire area. However, the boundaries of an MPO do not always correspond to the nonattainment or maintenance area boundary, nor does a nonattainment or maintenance area always contain one single MPO. Furthermore, a nonattainment or maintenance area boundary may encompass portions of more than one state. The conformity rule does not dictate how MPO planning boundaries are established; MPOs are established according to Titles 23 and 49 of the U.S. Code (as cited above) and DOT’s metropolitan planning regulations. Therefore, there may be more than one MPO responsible for transportation planning, and thus conformity determinations, in a nonattainment or maintenance area, as in Figure 2 below.page 5 Or, there may be some portion of the nonattainment or maintenance area that is not included in an MPO’s jurisdiction, also known as a “donut area” under the conformity rules. According to §93.101 of the conformity rule: “Donut areas are geographic areas outside a metropolitan planning area boundary, but inside the boundary of a nonattainment or maintenance area that contains any part of a metropolitan area(s). These areas are not isolated rural nonattainment and maintenance areas.” Though the word “donut” implies that the boundary of the MPO would be entirely within the nonattainment or maintenance area boundary to form two concentric circles, a nonattainment or maintenance area’s donut area may more typically resemble that in Figure 3 below.

There are also cases where a nonattainment or maintenance area’s boundary includes parts of more than one state, as in Figure 4 below. One MPO may cover the entire multi-state nonattainment or maintenance area, or MPOs may be established for each state’s portion of the area. In these situations, states may submit SIPs with identical budgets for the entire nonattainment or maintenance area, or may submit SIPs with budgets that cover only their state’s portion of the area.page 6 Finally, th ere are s ome MP Os in th e coun try which are r esp onsibl e f or tr an sportation plan ning in more th an on e n onattainment area. This guidance does in gen eral appl y to su ch MP Os . Th e No vemb er 24, 1993, co nformity rule addres ses th e case where an MPO is responsibl e f or more th an on e n onattainment area, which co ntin ues to appl y: “If a metrop olit an plan ning area i n cludes more th an on e n onattainment area, a co nformity det ermin at ion must be ma de f oreach nonattainment area. Emissions b udget s es tablishe d i n th e SIP( s) for th e i n cluded nonatta inme nt areas may n ot be co mbin ed or rea llo cated. Bu ild/no-bu ild tests must be applie d s e par ately in each nonattainment area” (58 F R 62208). Wh et hera n onattainment or maintenan ce area co nt ai ns more th an on e M P O, a do nut, or is lo cated with in mo re than one state, the conformity p rocess in cludes fle x ibility t o acco mmo dat e many di fferen ces in st ate and l o cal agency roles and plan ning pr o ces ses acr oss th e coun try. 5. Q. How i s this guidance o r ganized? A. The re maining p arts of this guidance cover how conformity d etermin at io ns and re gi on al em issions anal ys es th at s uppo rt th em are do ne in nonattainment and maintenance areas (“ areas”) , in th e f ollo wi ng ci rc um st ances :

• Part 2 co vers co nformity det ermin at ions and r e gi on al em issions anal ys es before an area h as SIP budget s forco nformity. Part 2 applies to all nonattainment areas where t r an sportation co nformity is re qui re d f orex isting and n e w ai rquality st andar ds, except 8- ho ur ozon e n onattainment areas wi th

adequat e orappr ov ed SIP budget s for th e 1- ho ur ozon e s t andar d (“ 1- ho ur b udget s ”) ;

• Pa rt 3 co vers co nformity det ermin at ions and r e gi on al em issions anal ys es af ter SIP b udget s are adequat e orappr ov ed f or th e appli cab le po llutant and s t andar d, an d applies to all ex isting and n e wl y

des i gnated areas where t r an sportation co nformity is re qui re d; an d

• Pa rt 4 co vers co nformity det ermin at ions and r e gi on al em issions anal ys es in 8- ho ur ozon e n onattainment areas th at have 1- ho ur b udget s, before su ch areas have adequat e orappr ov ed SIP budget s for th e 8- ho urozon e s t andar d.page 7 Pa rt 2: Confor mityDet erm inations and Regional Em is si ons Analyses Before SI P B udget s Are Ade quate or A pprove d 1. Q. To what areas does this part of th e guidance appl y? Part 2 o f this guidance applies to areas des i gnated n onattainment fora po llutant id en tifi ed in

§93.102( b) of th e co nformity rule th at do not yet have b udget s fora s t andar d th at can be used i n

co nformity. Some examples of areas in clude:

• a ll P M 2.5 nonattainme ntareas be fore PM 2.5 SIP budget s are f o und adequat e or appr ov ed;

• 8 -hour ozon e areas wi thout adequat e orappr ov ed 1- ho ur ozon e SIP budget s, before 8- ho ur ozon e SIP budget s are f o und adequat e orappr ov ed;

• any 1

- ho ur ozone, carbon mo noxi de, or PM 10 nonattainme ntarea that ha s no adequat e orappr ov ed budget s for th at st andar d. This part of th e guidance does not co ver:

• 8-hour ozon e n onattainment areas wi thout adequat e orappr ov ed 8- ho ur b udget s, but wi th

adequat e orappr ov ed 1- ho ur budget s; please r efer to Part 4 o f this guidance.

• mai nt enance areas , as th ese areas by def inition have appr ov ed SIPs wi th b udget s. 2

2. Q. Wh at tests are used f or th e r e gi on al em issions anal ysis before a n onattainment area h as motor vehi cle em issions b udget (s) th at are adequat e orappr ov ed? A. Co nformity applies foran ai rquality st andar d on e year af ter th e ef f ect iv e dat e of EP A’ s nonattainme ntd esignatio n f or that standard. EP A g e ne rally be lie ve s that conformity will a ppl y fo r a standard be fo re an area is ab le to sub mit a SIP fo r that st andar d co nt ai ning b udget s and t hos e budget s are f o und adequat e. Sect ion 93.119 o f the co nformity rule pr ovid es di r ect ion for ho w t h e r e gi on al em issions anal ysis must be do ne before b udget s are avai labl e. Dur ing this time per iod, th ese areas must use t h e i nterim emi ssi on s t e stor te sts: the build/no-build te st , and/or the ba se line year te st
.

2 A main tenance area could have a special type of main tenance plan ca lle d a limit ed maintenan ce plan

. Please see t h e J uly 1, 2004, final rule at 69 F R 40063 and t h e J une 30, 2003, pr opos ed rule at 68 F R 38983-4 f or more informat ion ab out co nformity an d limit ed main tenance plan s.page 8 3. Q. Wh at geo g ra phic area m ust be exam in ed i n re gi on al em issions anal ys es and co nformity det ermin at ions before a n onattainment area h as adequat e orappr ov ed budget s? A. In this case, a co nformity det ermin at ion fora t r an sp ortation plan , TIP, orpr oj ect not from a plan or TIP must be base d o n a r e gi on al em issions anal ysis th at co vers th e en tire nonattainment area, to satisfy th e s t atute and r e gulat ions. Sect ion 93.122(a) (1) of the co nformity rule st ates : “the re gi on al em issions anal ysis re qui re d b y §§93.118 and 93.119 f or the tr an sp ortation plan , TIP, orpr oj ect not from a co nforming plan and T IP must in clude all re gi on ally si gnifi can t pr oj ect s expected i n the nonattainment or maintenan ce area. ” Th ere m u st be a r e gi on al em issions anal ysis for th e en tire nonattainment area, whet her the nonattainment area i n cludes on e M P O o r more th an on e M P O, a do nut area, po rtions of more th an on e s t ate, oran y

co mbin at ion of th ese j urisdictions. Pl ease s e e t h e n ext Q &A for th e o ptions in creat ing a r e gi on al em issions anal ysis foran en tire area. Forall nonattainment areas co vere d b y Part 2 o f th e guidance, th e M P O( s) mu st co or di nate th ei rplan/T IP co nformity det ermin at ions to get h er , pur su an t to §93.124(d) of th e f inal co nformity rule. In th e No vemb er 24, 1993, final rule, EPA st ated: “Wh ere a n onattainment area i n cludes mu ltiple MP Os , th e co ntrol strate gy SIP may ei th er allo cate em issions b udget s to each metropolit an plan ning area, or th e M P Os must act to get h er to make a co nformity det ermin at ion for th e n onattainment area. ” Once DOT r ecei ves all plan /TIP co nformity det ermin at ions fora gi ven nonattainment area, DOT w ill mak e it s conformity d etermin at io ns at the same t ime . In orderfo r one MP O t o updat e or revise its plan and T IP, a DOT co nformity det ermin at ion foreach plan and T IP in th at nonattainment area m ust be ma de at th e s ame time, acco rding t o §93.124(d) of th e rule. EPA be lie ves that it is necessary fo r the conformity d etermin at io ns and reg ional e mis sions anal ysis to in clude t h e en tire nonattainment area when th ere are n o SIP budget s to en sure th at th e r e qui rements of Cl ean Air Act s ect ion 176(c) (1) are met. Th at is, before SI P b udget s are avai labl e, in or der to det ermin e t h at tr an sportation act ivities w ill n ot cause a ne w ai rquality viol at ion, in crease t h e f r equen cy or severity of a v iol at ion, ordel ay timely atta inme nt or an y o thermile stone in the nonatta inme nt area, it is neces sary to co nsid er em issions from th e en tire area i n on e r e gi on al em issions anal ysis, and f orDOT to make all plan/TIP conformity d etermin at io ns at the same t ime

.page 9 4. Q. How can mu ltiple jurisdictions create a r e gi on al em issions anal ysis for th e en tire nonattainme ntarea? A. Th e agencies involv ed i n th e co nformity pr o ces s in a n onattainment area where t h ere i s more th an on e M P O o ra do nut area m ust use t h e co ns ul tation pr o ces s re qui re d b y §93.105 o f th e co nformity rule to decide h o w b est to me et this re qui rement, re gar dless of whet her th e area i s wi thin on e s t ate o r is a m ulti-st ate area. Th e co ns ul tation pr o ces s would b e used t o decide which interim em issions tests appl y

and what anal ysis year s ar e used. MP Os must use t h e s ame tests and anal ysis year s for th e en tire nonattainment area, as descri be d in the nextQ& A. No nattainment Ar eas With More Th an One M P O, In One o r More St ates : In nonattainment areas where t h ere i s more th an on e M P O, th e M P Os can dev elo p t he re gi on al em issions anal ysis for th e area i n

ei th er on e o f two ways: 1. by se par ate mo deling b y each MP O t h at is co mbin ed i nto on e r e gi on al anal ysis; or 2. by on e mo deling anal ysis for th e en tire nonattainment area. If MP Os in th e n onattainment area wan t to mo del th ei rem issions se par ately, each MPO would do a r e gi on al em issions anal ysis th at in cludes th e ex isting tr an sp ortation syst em in its part of th e n onattainment area as well as all ne w pr oj ect s in its plan and T IP. E ach MP O would s how th at th e appli cab le interim em issions test(s) are met foreach anal ysis year under th e r e gulat ions. Th ese r esults would t h en be co mpile d i n on e r e gi on al em issions anal ysis for th e en tire nonattainment area t h at would acco mp an y

each plan /TIP co nformity det ermin at ion. Th e M P Os in th e n onattainment area can wo rk in depen d en tly to co mplete th e r e gi on al em issions anal ysis for th ei r own parts of th e area, but a s ingle anal ysis would b e co mpile d f or th e en tire nonattainment area t o satisfy co nformity re qui re ments fo r an MPO’s plan /TIP. Altern at iv el y, th e r e gi on al em issions anal ysis could b e co mp lete d b y showing t h at the em issions in each anal ysis year for th e en tire nonattainment area meet th e appli cab le interim em issions test(s). Th e M P Os in th e area would wo rk to get h er to carry out a re gi on al em issions anal ysis for th e en tire nonattainment area t h at in cludes all of th ei rplan s and T IPs. Ag ai n, th ese mo deling r esults would b e presen te d i n on e r e gi on al em issions anal ysis for th e en tire nonattainment area t h at would acco mp an y th e co nformity determinatio nsforne w or re vi sed plans/TIPs in the nonattainme ntarea. As an example, s uppo se th ere are m u ltiple MP Os wi thin a n onattainment area and t h ey ar e demonstr at ing co nformity us ing t h e build/no-build test. If each MP O h as its own tr avel demand mo del and prefer s to run its own anal ysis, th e anal ysis must showei th er th at each MPO passes it s own bu ild /no-bu ild test; or the “bu ild ” scenar io s and the “no-bu ild ” s cenar ios from each MP O m ust be aggregated, and t h e t otal “b ui ld ” em issions from all MPOs mu st be le ss than the tota l “no-bu ild ” e mis sions fr om a ll M POs.page 10 Altern at iv el y, th e M P Os could i nitially create o n e r e gi on al em issions anal ysis for th e en tire nonattainment area t h at meet s th e b u ild/no-build test. In

ei th er case, to make t h e demonstr at ion re qui re d b y th e co nformity ru le, all MP Os must use t h e s ame test and t h e s ame anal ysis year s for th e r e gi on al em issions anal ysis. MP Os in on e n onattainment area may wan t to co or di nate th ei rplan and T I P updat e cycles as well as th e l ength of th ei rplan s, as des cribe d i n th e f ollo wi ng bullets.

< New o r revise d plan s and T IPs, as well as si gnifi can t changes to pr oj ect s, coul d re qui re a n e w r e gi on al em issions anal ysis (s ee §§93.104 and 93.122(g) of the co nformity rule). Coor di nation of plan and T I P updat e cycles among M P Os in the same nonatta inme nt area may minimiz e the numb er of new regional e mis sions anal ys es and co nformity det ermin at ions th at have to be co mplete d.

< Different tr ansp ortationplan leng th s wi thin on e nonatta inment area would require addi tion al anal ysis year s, b ecaus e acco rding t o §93.119(g) , an anal ysis must be per forme d f or th e l ast year of each plan . Forexample, if on e M P O’ s plan ends in 2025 and an other MP O’ s plan ends in 2030, both year s would h ave to be anal y

zed in th e r e gi on al anal ysis for th e en tire nonattainment area. Co or di nation of plan lengths may minimize t h e n umb er of anal ysis year s th at have to be exam in ed i n

an y on e r e gi on al em issions anal ysis. No nattainment Ar eas With a Do nut Ar ea: If th ere i s only on e M P O i n th e n onattainment area co n duct ing co nformity det ermin at ions, th e co nformity rule re qui res th e M P O t o in clude t h e em issions es timate d f rom th e do nut area’ s ex isting and pr opos ed t r an sportation syst em in th e r e gi on al em issions anal ysis for metropolit an tr an sportation plan and T IP co nformity det ermin at ions. Howev er, ei th er the MP O o r th e s t ate t r an sportation agency (“st ate DOT”) could es timate em issions from the do nut area as decided t hro ugh intera gen cy co ns ul tation, as explai ne d i n

Q& A 7 o f this part. If th ere i s more th an on e M P O as well as a do nut area i n

a n onattainment area, th e M P Os must wo rk to get h er and wi th th e s t ate DOT as appr opri ate t o create o n e r e gi on al em issions anal ysis for th e en tire nonattainment area t h at would acco mp an y

each plan /TIP co nformity det ermin at ion. Th e em issions es timate d f rom th e en tire area m ust meet the interim em issions test or tests, acco rding t o th e r e qui rements of §93.119. Ag ai n, the co ns ul tation pr o ces s would b e used t o co or di nate th e ch oi ce o f tests and anal ysis year s when several agencies are co mpleting em issions anal ys es , b ecaus e th e s ame tests an d anal ysis year s must be used as note d ab ov e.page 11 5. Q. Wh at deci sions mu st be ma de i n th e i ntera gen cy co ns ul tation pr oc es s? A. Th e agencies resp onsibl e f or th e co nformity det ermin at ion and r e gi on al em issions anal ysis in a n onattainment area, which are t h e M P Os and po ssibly th e s t ate DOT (s) for do nut area i n

a n onattainment area, should use t h e i ntera gen cy co ns ul tation pr o ces s to make certain deci sions. Under th e co nformity rule, th ere are s ome aspect s of co nformity th at must be co nsistent acr oss th e n onattainment area, even when th ere are more th an one MP O and t h ey each mo del th ei r own po rtion se par ately, as des cribe d ab ov e. Th es e in clude:

• t iming of p lan and TIP conformity d etermin at io ns , s o that DOT can make its co nformity det ermin at ions forall plan s and T IPs in a n onattainment area at the same t ime ;

• how th e r e gi on al em issions anal ysis is dev elo ped , i. e., whether e mis sions w ill b e mo del e d f oreach MP O’ s jurisdiction se par ately and s umme d t o get h er , or mo del ed for th e n onattainment area as a wh ol e;

• the in ter im emis sions test the nonatta inme nt area w ill me et, in the areas that mu st meet only on e t est as re qui re d b y §93.119 ( e.g., PM 2.5 areas or8- ho ur ozon e areas th at are clas sifi ed as margin al ordes i gnated under Clean Air Act, part D, subp art 1 th at do not have 1- ho urb udget s). EPA be lie ves that fo r cons is tenc y and in order to satisf y t he conformity ru le , the same test mu st be used in a ll p ort io ns of the nonatta inme nt area in areas that have th e ch oi ce o f interim em issions tests. In otherwo rds, it would n ot be accept able foron e MPO to u se th e build/n o- build te st and an oth er MPO wi thin th e same nonattainment area t o use t h e b aselin e year test, b ecaus e th e rule re qui res th at one test be met for th e en tire nonattainment area, acco r di ng to §§93.119 an d 93.124(d); 3

• the anal ysis year s for th e i nterim em issions test(s), as re qui re d b y §93.119(g)

. Again, EPA be lie ves that anal ysis ye ars mu st be cons is tent in a ll p ort io ns of the nonattainment area, even if

em issions are mo del e d f oreach MP O’ s jurisdiction se par ately, otherwis e t h ey can not be summe d t o get h er to pr o duce a co mplete anal ysis to satisfy th e t est. Regi on al em issions anal ys es forall MP Os must co ver

3 In 8- ho ur and 1- ho ur ozon e areas clas sifi ed mo der ate or hi gher , serious CO, an d mo der ate CO areas wi th

a des i gn valu e greater th an 12.7 ppm , both interim em issions tests must be met under §93.119. Please read Sect ion IV.D. of th e pream bl e o f th e J uly 1, 2004, final rule fo r f urt he r e xplanation.page 12 th e s ame time per iod and t h us n eed t o in clude t h e l ast year of each tr an sportation plan

. As des cribe d i n th e ab ov e example, in a n onattainment area wi th two MP Os wher e on e M P O’ s tr an sp ortation plan co vers a 25- year per iod from 2005 t o 2030, an d th e o ther MP O’ s plan co vers only a 20- year per iod from 2005 t o 2025, the re gi on al em issions anal ysis for both MP Os must exam in e em issions in th e year s 2025 an d 2030; an d

• the emi ssi on s mod el used f or th e i nterim em issions test(s), in th e case where t h er e is more th an on e em issions mo del version th at could b e used, per §93.111 o f the ru le. In addition, the MPO jurisd ic tions in vo lv ed in the conformity d etermin at io n(s) fo r the nonatta inme nt area shou ld discuss the planning assump tions they w ill u se in the regional em issions anal ysis and t h e s o urces of th at informat ion. Sect ion 93.105(c) (1)(i) of th e rule sp ecifically require s t hat planning a ssumption s b e di sc u sse d in the interagency consultation pr o ces s. Wh ere feas ible and appr opri ate, MP Os and where appli cab le, st ate DOT s should use co nsistent plan ning as sumptions for th e r e gi on al em issions anal ysis in th ei r jurisd ic tions.

6. Q. In a n onattainment area t h at does not have SIP budget s forco nformity, if on e M P O i n th e area can meet th e r e qui rements of §93.119 o f th e ru le, but an other MP O o ra do nut area can not, can th e M P O t h at meet s th e r e qui rements show th at its plan and T IP co nform and pr o ceed? A. No . EPA believes th at before b udget s are adequat e orappr ov ed, th e wh ole nonattainment area m u st co nform to meet th e C l ean Air Act 176(c) (1) re qui rements. These require me nts are that transportation act ivitie s w ill n ot:

< caus e a n e w ai rquality viol at ion,
< in crease t h e f r equen cy or severity of a v iol at ion, or
< de lay timely atta inme nt or an y o thermile stone in the area fo r an air qua lit y st andar d. It is necessary to est imate e mis sions fr om the entire nonatta inme nt area in a ll p lan/TIP co nformity det ermin at ions and t h e suppo rting r e gi on al anal ysis b ecaus e se par ate SIP b udget s are n ot yet avai labl e. Forexample, in Fi gure 2 r e peated b elo w, th ere are t wo MP Os. If they choose to mod el their emi ssi on s se parately and We st MP O appear s t o pa ss th e appli cab le test(s) of §93.119 but East MP O does not, West MP O can not pr o ceed t o det ermin e co nformity al on e. It can not be kn own for sure th at West MP O’ s tr an sportation plan and T IP would n ot caus e a n e w v iol at ion, in crease t h e f r equen cy or severity of apage 13 violation, or delay timely attainment (or other milestone) in the area, because East MPO cannot also pass the test. Thus, the nonattainment area in this example as a whole cannot demonstrate that it will not cause or contribute to violations. To resolve this situation,

East and West MPOs would consult on what options are available for demonstrating conformity, including the option of adding or modeling their emissions together to see if they pass the applicable regional emissions test(s). 7. Q. Who is responsible for estimating emissions in a donut area of a nonattainment or maintenance area? A. In a nonattainment or maintenance area with a donut area, the lead agency for developing the regional emissions analysis that applies to the donut area can be: • he MPO within the nonattainment area. In some cases, an adjacent MPO is better suited to conduct such an analysis. An MPO could run an analysis for the donut area’s projects, or include the donut area’s projects in the regional emissions analysis supporting its plan and TIP. An MPO could also include the donut area’s projects in its plan and TIP, but this practice is not common; • the state DOT . In some cases, the state DOT may take the lead in conducting regional emissions analysis for the donut area; or • another local planning agency . In limited cases, another local planning agency in the donut area (e.g., a county planning commission) may also be the lead agency for the donut area. Section 93.105(c)(3) of the conformity rule relies on the interagency consultation process (including the MPO and state DOT) to determine how best to consider projects that are planned for donut areas located outside the metropolitan area and within the nonattainment or maintenance area in the conformity process. Section 93.105 also requires that such procedures for demonstrating conformity of donut area projects be included in an area’s conformity SIP that is approved by EPA according to §51.390 of the rule. tpage 14

[This p age in tent io na lly left blank]page 15 Pa rt 3: Confor mityDet erm inations and Regional Em is si ons Analysis Once SI P B udget s Are Ade quate/Approve d Gen eral 1. Q. To what areas does this part of th e guidance appl y? A. Part 3 applies to areas des i gnated n onattainment foran y

po llutant id en tifi ed i n §93.102( b) of th e rule, on ce t h e area h as adequat e orappr ov ed budget s from a SI P addres sing a partic ular st andar d fora po llutant. This part of th e guidance applies to:

• an 8- ho ur ozon e n onattainment area o n ce i t has adequat e orappr ov ed budget s for th e 8- ho ur st andar d , re gar dless of whet her or not th e area h a d 1- ho ur b udget s;

• a PM 2.5 nonattainment area o n ce i t has adequat e orappr ov ed P M 2.5 SIP budget s;

• any 1

- ho ur ozone, carbon mo noxi de, or PM 10 nonattainme ntarea that ha s adequat e orappr ov ed budget s from a SIP addres sing th at st andar d; an d

• mai nt enance areas , as th ese areas by def inition have appr ov ed SIPs wi th b udget s. 4

2. Q. How do nonattainment and maintenan ce areas det ermin e co nformity fora gi ven st andar d on ce adequat e orappr ov ed SIP budget s are avai labl e f or th at st andar d? A. Cl ean Air Act s ect ion 176(c) (1 ) st ates th at fe der al act ivities must co nform to th e SIP. Once a SIP wi th b udget s has b een submitte d and E PA finds th e budget s adequat e or appr ov es th e SIP, th e “b udget test ” us ing t h e n e w budget s must be used f orco nformity det ermin at ions acco rding t o §§93.109 and 93.118 o f th e co nformity rule. EPA’s adequacy finding o rappr ov al mean s th at th e SIP’ s b udget s are an appr opri ate measure f or whet her tr an sportation act ivities co nform due t o many f act ors, in cludi ng: • the b udget s are i d en tifi ed and preci sely quan tifie d;

• the budget s are co nsistent wi th th e SIP’ s purpo se of r eas on ab le furtherpr ogress, at tainment, or maintenan ce o f an ai rquality st andar d; an d

4 A main tenance area could have a special type of main tenance plan ca lle d a limit ed maintenan ce plan

. Please see t h e J uly 1, 2004, final rule at 69 F R 40063 and t h e J une 30, 2003, pr opos ed rule at 68 F R 38983-4 f or more informat ion ab out co nformity an d limit ed main tenance plan s.page 16

• the b udget s are co nsistent wi th

and clear ly relate d t o th e em issions inventory an d th e co ntrol measures in th e S IP. 5

3. Q. Wh at geo gra phic areas might b udget s from a SIP addres s, and h o w i s co nformity gen erally det ermin ed i n multi-jurisdiction al areas wi th

SIP budget s? A. In a n onattainment or maintenan ce area l o cated en tirely wi thin on e s t ate, th e s t ate ai r agency may dev elo p a S IP th at es tablishes ei th er :

• a budget (or b udget s) th at applies to th e en tire nonattainment or maintenan ce area, or

• a subar ea budget (or budget s) foreach MP O wi thin th e n onattainment or maintenan ce area. In

a m u lti-st ate n onattainment or maintenan ce area, th e s t ate ai ragencies may decide t o es tablish SIPs in each st ate t h at co nt ai n

ei th er : • i den ti cal b udget s th at appl y to th e en tire nonattainment or maintenan ce area, or

• uni que budget s th at appl y only to on e s t ate’ s po rtion of th e n onattainment or maintenan ce area. State and l o cal agencies can dev elo p SIPs in many di fferent ways. Sect ion 93.124(d) of th e co nformity ru le ackn o wledges this f act and co vers SIPs dev elo ped i n

areas wher e th ere i s more th an on e M P O: “If a n onattainment area i n cludes more th an on e M P O, th e i mp lement at ion plan may es tablish motor vehi cle em issions b udget s foreach MP O, orel se th e M P Os must co ll ect iv el y make a co nformity det ermin at ion for th e en tire area. ” Once budget s have b een fo und adequat e orappr ov ed, th e co nformity det ermin at ion(s) an d re gi on al em issions anal ysis is do ne for th e geo g ra phic area t h at is addres se d b y the b udget s in th e SIP. This gen eral pr in ciple applies in all situ at ions, al tho ugh th ere i s fle x ibility in how the regional e mis sions anal ysis is deve lo ped, and in coordinating co nformity det ermin at ions, when several MP Os are i nvolv ed. Th e t abl e o n th e n ext page summarizes th e gen eral situ at ions. Th e ques tions and an sw er s th at follo w pr ovid e f urther det ail on th e di fferent ci rc um st ances th at can o ccur .

5 Th ere are o thercr it er ia th at SIP budget s must meet for EPA to find th em adequat e; for th e f ull list of adequacy cr it er ia, s ee §93.118(e) of th e co nformity rule.page 17 Summary Table: How SIPs A ffe ct Geograph ic Areas Cons id ered in Conformit y Fo r a nonattainme nt or maintenan ce area lo cated: where SIP budget s are es tablishe d f or: th e geo g ra phic area co nsid ered i n re gi on al anal ysis is: th e geo g ra phic area co nsid ered i n final conformit y determin at io n(s) is : wi thin on e s t at e the en tire area th e en tire area* th e en tire area** wi thin on e s t at e s ubareas each subarea each su barea in mu ltiple st ates th e en tire area th e en tire area* th e en tire area** in mu ltiple st ates each st at e each st at e each st at e * There is fle x ibility in how the reg ional e mis sions anal ysis is done when there is mo re th an on e M P O. S ee b elo w f or more det ails. ** There may b e mo re than one p lan/TIP conformity d etermin at io n in a nonatta inme nt or maintenan ce area becaus e th ere may be more th an on e M P O maki ng det ermin at ions for separate plans and TIPs. There is fle x ibility in how these conformity d etermin at io ns are coordinated. See be lo wfo rmo re deta ils

.
No nattainment or Maintenan ce A r eas Lo cated i n

One State, Wh ere Budget s Ar e E stablishe d f or th e En ti

re Area 4. Q. How i s co nformity do ne when b udget s are es tablishe d f oran en tire nonattainment or maintenan ce area t h at is wi thin on e s t ate? One MP O. In th e s imp lest case, an area i s lo cated en tirely wi thin on e s t ate and t h e M PO bo undary is th e s ame as th e n onattainment/mai nt enance area b o undary (Fi gure 1) . In Fi gure 1, th e n onattainment or maintenan ce area b o undary, th e M P O, and t h e SIP budget s all addres s th e s ame geo gra phic area. In this case, b ecaus e th e S IP es tablishes b udget s for the entire area, the MPO w ill u se those budget s in th e r e gi on al em issions anal ysis do ne for the MPO’s plan/TIP conformity d etermin at io n fo r the entire nonatta inme nt ormain tenance area.page 18

More than One MPO. When budgets are established for the nonattainment or maintenance area as a whole, and there is more than one MPO, the MPOs would complete their respective plan/TIP conformity determinations and submit them to DOT, as explained in Part 2, Q & A 3. Once all determinations for a given area are received, DOT would make its conformity determinations at the same time. The MPOs must collectively develop a regional emissions analysis for the entire area that meets the requirements of §93.118 of the rule that would accompany all plan/TIP conformity determinations. For example, all MPOs would have to use the same analysis years for the regional emissions analysis. Each MPO would show conformity of its plan and TIP using the regional emissions analysis done for the entire area. See Part 2, Q & A 4 for more information. The MPOs can develop the regional analysis for the area in either one of two ways: 1. Each MPO can model emissions for its geographic part of the nonattainment or maintenance area separately. For each analysis year, the emissions estimated by each MPO would be summed together and compared to the area’s applicable budgets. EPA believes that the MPOs must all use the same analysis years when completing the budget test in accordance with §93.118. 2. The MPOs could also work together to model the entire nonattainment or maintenance area as a whole at the same time. In this case, §93.118 of the conformity rule would be met if estimated emissions in each analysis year are less than or equal to the area’s applicable budgets. MPOs in one nonattainment or maintenance area may want to coordinate their plan and TIP update cycles as well as the length of their plans.

< New or revised plans and TIPs, as well as significant changes to projects, could require a new regional emissions analysis (see §§93.104 and 93.122(g) of the conformity rule). Coordination of plan and TIP update cycles among MPOs in the same nonattainment or maintenance area may minimize the number of new regional emissions analyses and conformity determinations that have to be completed.page 19

< Different tr ansp ortationplan leng th s wi thin on e nonatta inment or main te nance area would r e qui re addi tion al anal ysis year s, be caus e acco rding t o §93.118(d) , an anal ysis must be per forme d f or th e l ast year of each plan . Forexample, if one MP O’ s plan ends in 2025 and an other MP O’ s plan ends in 2030, both year s woul d have to be anal y

zed i n th e r e gi on al anal ysis for th e en tire nonattainment area. Co or di nation of plan lengths may minimize t h e n umb er of anal ysis year s th at have to be exam in ed i n

an y on e r e gi on al em issions anal ysis. One or Mo re MP Os and a D o nut A rea: If there is only o ne MPO in the nonatta inme nt or maintenan ce area co n duct ing co nformity det ermin at ions, th e r e gulat ions re qui re the MP O t o in clude t h e em issions es timate d f rom th e do nut area’ s ex isting and pr opos ed tr an sportation syst em in th e r e gi on al em issions anal ysis for th e metropolit an tr an sportation plan and T IP co nformity det ermin at ions. Howev er, ei th er th e M P O o r th e s t at e tr an sportation agency (“st ate DOT”) could es timate em issions from th e do nut area as decided t hro ugh intera gen cy co ns ul tation, as explai ne d i n

Part 2, Q& A 7. If th ere i s more th an on e M P O as well as a do nut area i n

a n onattainment or maintenance area, th e M P Os must wo rk to get h er and wi th th e s t ate DOT or otherdo nut area agency as appr opri ate t o create o n e r e gi on al em issions anal ysis for th e en tire area t h at woul d acco mp an y

all plan /TIP co nformity det ermin at ions. Th e em issions es timate d f rom the en tire area m ust be less th an orequal to th e budget (s) es tablishe d f or th e en tire area, acco rding t o th e r e qui rements of §93.118. Th e co ns ul tation pr o ces s would b e used t o co or di nate th e anal ysis year s when several agencies are co mpleting em issions anal ys es , b ecaus e th e s ame anal ysis year s must be used.

No nattainment or Maintenan ce A r eas Within One S t ate, Wh ere t h e S IP Establishes Subarea B udget s 5. Q. How do nonattainment or maintenan ce areas wi th more th an on e M P O i n

a s ingle st at e det ermin e co nformity on ce SIP budget s are adequat e orappr ov ed, and t h e SIP es tablishes subar ea budget s foreach MP O? A. Wh en subar ea budget s are created f oreach MP O, th e s um of th e s ubar ea budget s equal s th e t otal amount of em issions th e area can have from th e t r an sportation s ect oran d st ill make progress toward, atta in , ormain ta in the standard. Therefore, if each MPO meet s its subar ea budget s fora po llutant and s t andar d in acco rd ance wi th th e r e qui rements of

§93.118, th en th e en tire area meet s th e t otal SIP’ s purpo se for th at po llutant an d st andar d. As EPA note d i n th e J anu ary 11, 1993, co nformity pr opos al ,page 20 “s ubarea budget s pr ovid e addi tion al as suran ce t h at thro ugh future conformity d etermin at io ns transportation plans and TIPs w ill p roduce e mis sion patterns that w ill a chie ve atta inme nt” (58 FR 3780). Wh en th e SIP f oran area es tablishes subar ea budget s forco nformity purpo ses, th es e subar ea budget s must be met forplan s and T I Ps in th e area t o co nform, as re qui re d i n §93.124(c) and ( d) of th e co nformity rule. Sect ion 93.124(c) st ates : “I f t he ap p lic ab le impleme ntat io n plan (orimpleme ntat io n plan sub mis sion) est imates future e mis sions by geographic subarea of the nonatta inme nt area, th e M P O and DOT are n ot re qui re d t o co nsid er this to es tablish subar ea budget s, unless th e appli cab le implement at ion plan (or impleme ntat io n plan sub mis sion) exp licitly in dicates an in tent to create such subar ea budget s for th e purpo ses of co nformity.” Th e M P Os can make i n depen d en t co nformity det ermin at ions for th ei rplan s and T IPs as lo ng as all of the ot he r subareas in the nonattainme ntor mainte nanc e area have co nforming t r an sportation plan s and T IPs in place at th e t ime of each MP O’ s and DOT ’s plan /TIP d ete rm ination. In othe r w o rd s, unde r t he conformity ru le in orde r f o r an MPO or DOT to det ermin e co nformity for its subar ea, th e r est of th e area m ust al so be in co nformity. Th e pream bl e t o th e No vemb er 24, 1993, co nformity rule explai ns this as follo ws: “The SIP may sp eci fy em issions b udget s for subare as of th e r e gi on, pr ovid ed t h at th e S IP in cludes a demonstr at ion th at th e s ubr egi onal em issions b udget , when co mbin ed wi th

all otherpo rtions of th e em issions in

ventory, w ill r esu lt in atta inme nt and/ormain tenance of the standard. Th e co nformity det ermin at ion must demonstr ate co nsistency wi th

each subr egi onal em issions b udget in th e SIP” ( 58 F R 62196)

. Th us , when an y su bar ea demonstr ates co nformity, it must be demonstr ated t h at all subar eas have co nforming plan s and T I Ps . Forexample, s uppo se th e s ubar ea budget s in a SIP h ave just b een fo und adequat e, and o n e o f th e M P Os in th e area n e eds to updat e its TI P. Th at MP O can make a co nformity det ermin at ion us ing i ts subar ea budget s for the first time wi thout wai ting f or th e o ther MP Os in th e area, as long as th e o ther MP Os have co nforming plan s and T IPs in place, even if th ese plan s and T IPs wer e prev io us ly fo und t o conform u s ing the in ter im emis sions test(s).page 21 Once an area h as adequat e orappr ov ed s ubar ea budget s, if co nformity la pses 6 fo r one subar ea, th e o ther subar ea( s) can co ntin ue t o implement pr oj ect s in th ei rcurrently co nforming plan s and T IPs, but th ey can not make n e w plan and T IP co nformity determin at io ns unt il t he la pse is reso lv ed and conformity is determin ed in the la psed subar ea. In otherwo rds, if th e co nformity st atus of on e s ubar ea l a pses , th e ex isting plan s and T I Ps in other subar eas co ntin ue t o be valid an d co ns equences would n ot appl y to an y other subar eas unless th e l a pse i s not resolv ed b y th e t ime other subar eas n eed t o make new conformity d etermin at io ns.

6. Q. Why can ’t an MP O t h at has its own subar ea budget s det ermin e co nformity of its tr an sportation plan and T IP when an other MP O i n th e s ame area i s in a l a pse? A. Sect ion 176(c) of th e C l ean Air Act clear ly st ates th at co nformity applies in nonattainment and maintenan ce areas , rath er th an in di vi dual metrop olit an plan ning areas . Sect ion 176(c) al so st ates th at th e f e der al go vernment and M P Os can not appr ove tr an sportation act ivities unless th ey co nform to th e SIP and i ts b udget s. Th eref or e, in a nonatta inme nt ormain tenance area with mo re than one MPO, a ll M POs mu st conform even if th e SIP h as es tablishe d s ubar ea budget s. If an in d ividua l M PO la pses, it has not de mo nstrated that it can conform t o it s subarea b udget s. Th eref or e, th ere i s no way for th e o ther MP Os in th e s ame area t o kn ow whet her th ei r tr an sportation plan s and T IPs are co nsistent wi th th e S IP as a wh ol e. Us ing Fi gure 2 agai n

as an example ( found in Part 2, Q &A 6) , if East MP O i s in a co nformity la

pse, it cannot be assured that West MPO’s transportation act ivitie s st ill me et the purpose of th e SIP even if West MP O meet s its subar ea budget s. Th at is, it is unkn own whet her th e t otal amount of em issions in th e area f rom th e plan ne d t r an sportation s ect orwould s till meet th e S IP’s purpo se of pr ogress to war d, at tainment of, or maintenan ce o f th e s t andar d, b ecaus e East MP O can not meet its subar ea budget s. Wh en on e s ubar ea l a pses , th ere i s no way forth e oth er MPO to s h ow th at th eir planned tr ansp ortationactivities would conf orm to th e S IP for th e wh ol e area un til th e l a pse i s resolv ed.

6 A la pse i s def ine d i n

§93.101 o f th e rule : “ Laps emean s th at th e co nformity det ermin at ion fora t r an sportation plan or TIP has expi re d, and t h us th ere i s no currently co nforming tr an sportation plan or TIP.” A la pse occur s when co nformity of a plan or TIP is not det ermin ed acco rding t o th e f r equen cy re qui rements of §93.104 o f th e co nformity rule.page 22 7. Q. How do I kn owwhet her th e SIP es tablishes subare a budget s? Ar e coun ty-by- coun ty em issions pr oj ect ions subar ea budget s? A. Th e SIP m u st sp eci fi cally st ate t h at it creates subar ea budget s. Co un ty-by- coun ty em issions pr oj ect ions in a SIP i nventory are n ot subar ea budget s unless th ey ar e sp eci fi cally labele d as su ch

. Sect ion 93.124(c) of th e co nformity rule st ates , “I f t he ap p lic ab le impleme ntat io n plan (orimpleme ntat io n plan sub mis sion) es timates future em issions by geo gra phic subar ea o f th e n onattainment area, the MP O and DOT are n ot re qui re d t o co nsid er this to es tablish subar ea budget s, unle ss the app lic ab le impleme ntat io n plan (orimpleme ntat io n plan sub mis sion) explicitly in dicates an intent to create s u ch subar ea budget s for th e purpo ses of conformity. ” If county le ve l emis sions project io ns are in cluded in a SIP but not exp licitly d e fin ed as subar ea budget s for th e purpo ses of co nformity, th e SIP i s co nsid ered t o have budget s for th e en tire area and M P Os must wo rk to get h er to have plan /TIP co nformity det ermin at ions for th e en tire nonattainment or maintenan ce area appr ov ed b y DOT at th e s ame time, as des cribe d ab ov e i n

Q &A 4 o f this part and Part 2, Q &A 4. A cco rding t o §93.124(d) , “If a n onattainment area i n cludes more th an on e M P O, th e i mp lement at ion plan may es tablish motor vehi cle em issions b udget s foreach MP O, orel se th e M P Os mu st co lle ct iv el y make a conformity d etermin at io n fo r the entire nonatta inme nt area. ” If MPOs within one nonattainme ntor mainte nanc e area wou ld prefer to havesubarea b udget s, th ey should co mmuni cate t h ei rpreference t o th e s t ate and l o cal ai ragencies wi thin th e in te ragency consul tationpr oc ess during th e developmen t of th e SIP. Section 93.105(c) of th e co nformity rule re qui res intera gen cy co ns ul tation on th e dev elo pmen t of SIPs, as well as tr an sportation plan s, TIPs, and co nformity det ermin at ions.

Mu lti-St ate No nattainment/M ai nt enance A r eas : 8. Q. How do multi- state nonatta inme nt and main tenance areas determin e conformity if e ach st ate s ubmits a SIP t h at co nt ai ns th e s ame b udget s for th e en tire multi-st ate area? A. If th ese m u lti-st ate areas have SIPs th at co nt ai n b udget s for th e m ulti-st ate area as a wh ol e, on e r e gi on al em issions anal ysis would b e co mplete d f or th e en tire area us ing t he b udget test, acco rding t o th e r e qui rements in §93.118 o f th e co nformity rule. This re gi on al anal ysis would acco mp an y

all plan /TIP co nformity det ermin at ions in th e area t h at would b e submitte d t o DOT

. Once all det ermin at ions fora gi ven area are recei ve d, DOT would make it s conformity d etermin at io ns at the same t ime . The MPOs mu st co lle ct iv elypage 23 develop a regional emissions analysis for the entire area that meets the requirements of §93.118 that would accompany all plan/TIP conformity determinations. For example, all MPOs would have to use the same analysis years for the regional emissions analysis. Each MPO would show conformity of its plan and TIP using the regional emissions analysis done for the entire area. For example, in Figure 4, repeated below, suppose there is one budget for the multi-state area, but each state has its own MPO. In this case, one regional emissions analysis would be made for the entire oval and the conformity determinations for each MPO’s plans and TIPs within the area would be based on this regional emissions analysis. DOT would wait to make its conformity determinations for the plans and TIPs in the area until it receives all of them. This answer is similar to single state areas with SIP budgets that cover the entire nonattainment or maintenance area. See Q & A 4 of the part, and Part 2, Q & A 4, for further information.

9. Q. When would it be likely for state air agencies in a multi-state nonattainment or maintenace area to submit SIPs with budgets that apply to the entire area? A. This option would most likely be chosen in areas where there is one MPO responsible for the transportation planning of the entire multi-state nonattainment or maintenance area. However, the option is available to any multi-state nonattainment or maintenance area. In areas with more than one MPO, additional coordination would be necessary for plan/TIP conformity determinations and the regional emissions analysis because they would need to cover the entire nonattainment or maintenance area pursuant to §§93.124(d) and 93.118.page 24 10. Q. Howis conformity d etermin ed fo rmulti- state nonatta inme nt ormain tenance areas when each st ate s ubmits a S IP th at co nt ai ns b udget s only for its st ate’ s po rtion of the area? A. States in a m u lti-st ate area h ave th e o ption of submitting SIPs wi th b udget s for just th ei r own po rtion of th e area t h at , when taken to get h er , meet th e appli cab le Clean Air Act re qui rement. Wh ere s t ates have do ne so and E PA has fo und s u ch b udget s adequat e, the MP O o r MP Os in each st ate wi th su ch b udget s can det ermin e co nformity co mpletely in depen d en tly of th e o ther st ates . EPA co ncl uded t h at th ese s t ates can op erat e in depen d en tly forco nformity b ecaus e th e Clean Air Act refers to co nformity to a S IP. E ach st ate’ s SIP in th ese cases in cludes inventories, co ntrol measures and pr ograms, an d b udget s th at appl y to only th at st ate’ s po rtion of th e n onattainment or maintenan ce area. States th at have SIPs wi th

adequat e orappr ov ed budget s for only th ei r own po rtions of a mu lti-st ate area are di stin ct from MP Os in a n onattainment or maintenan ce area t h at have subar ea budget s wi thin th e s ame SIP, and al so di stin ct from st ates th at have SIP budget s th at appl y to an en tire multi-st ate n onattainment or maintenan ce area. Wh ere s t ates have th ei r own SIP budget s, if a co nformity la pse i s o ccurring in on e s t ate’ s po rtion of an area, th e M P O( s) in th e o ther st ate( s) in th e n onattainment or maintenan ce area can co ntin ue t o make co nformity det ermin at ions for ne w o r revise d t r an sportation plan s and T IPs b ecaus e th ey co ntin ue t o showco nformity to th ei rSIP’ s b udget s. Us ing F i gure 4 ab ov e as an example, s uppo se St ates A, B, and C each have SIPs wi th adequat e orappr ov ed budget s th at appl y only to th ei r own st ate’ s po rtion of th e area. If St ate A la pses , St ates B and C can co ntin ue t o make n e w co nformity det ermin at ions. In co ntrast, as des cribe d prev io us ly:

• M POs th at have subar ea budget s wi thin on e SIP are det ermining co nformity to the same SIP, th eref or e when on e makes a co nformity det ermin at ion, all other subareas mu st be in conformity a s we ll in order to show conformity t o the SIP; and

• m ul

ti-state areas th at have b udget s for th e en tire nonattainment or maintenance area are al so det ermining co nformity to th e s ame SIP, th eref or e, th ere m u st be one re gi on al em issions anal ysis for this area and co nformity det ermin at ions forplan s and T IPs in th e area m ust be ma de at th e s ame time as des cribe d i n

Q &A 8 o f this part.page 25 Pa rt 4: Confor mityDet erm inations and Regional Em is si ons Analyses in 8-Hour Ozone No nattainm e nt A reas With A de quate or A pproved 1-Hour SI P B udge ts B ackgr ound 1. Q. To what areas does this part of th e guidance appl y? A. This p art of the guidance clar ifie s the impleme ntat io n of conformity in nonatta inme nt areas for th e 8- ho ur ozon e s t andar d th at wer e nonattainment or maintenan ce areas for the 1- ho ur ozon e s t andar d and h ave adequat e orappr ov ed SIP budget s th at addres s th e 1- ho ur ozon e s t andar d. Howev er, this part of th e guidance applies only un til th ese areas have 8- ho ur budget s th at th ey can use f orco nformity. Once an area s ubmits an 8- ho ur SIP wi th b udget s and E PA finds th e budget s adequat e orappr ov es th e 8- ho ur SIP t h at co nt ai ns b udget s, th at area m ust use t h e 8- ho ur budget s forco nformity acco rding t o §93.109(e) (1) of th e co nformity rule. At th at po int, Part 3 o f this guidance would appl y, and P art 4 would n o long er be relevant to th at area. In Part 4 o f th e guidance, th e t erms:

• 8 -h our area mean s a n onattainment area f or th e 8- ho ur ozon e s t andar d, an d • 1 -h our area mean s a n onattainment or maintenan ce area f or th e 1- ho ur st andar d. Th e J uly 2004 f inal rule allo ws 8- ho ur areas wi th

1- ho ur SIPs to implement co nformity in th e s ame way as th ey have b een under th e 1- ho ur st andar d, to th e extent po ssibl e. In otherwo rds, th e 8- ho ur areas wi th

1- ho ur b udget s w ill c ont in ue to use them wherever po ssibl e. This part of th e guidance i s intend ed t o as sist in under standing h o w t h at gen eral pr in ciple applies in various ci rc um st ances . 2. Q. How i s Part 4 o r ganized? A. Part 4 i s or ganized under h eadi ngs for b ackgr ound, bo undary s cenar io, and gen eral impleme ntat io n topics, as follo ws: B ackgr ound ( ques tions 1 - 8) ; Scenar io 1 (ques tions 9 - 11) ; Scenar io 2 (ques tions 12 - 13) ; Scenar io 3 (ques tions 14 - 18) ; Scenar io 4 (ques tions 19 - 22) ; an d Gen eral Im plemen tation of th e F inal Rule ( ques tions 23 - 25)

.page 26 3. Q. What are the ways an 8-hour area could be related to a 1-hour area that has adequate or approved 1-hour budgets? A. As described in the July 1, 2004, conformity rule, there are four generic scenarios for how 8-hour area boundaries relate to 1-hour area boundaries, and the conformity rule is written with these four scenarios in mind. To determine which scenario appropriately describes an area, it is necessary to consider the boundary of the entire 8-hour area. For example, in a multi-state 8-hour area, the 8- hour boundary refers to the entire multi-state area, rather than each state’s individual portion. Figure 5 illustrates the four generic boundary scenarios.

• Scenario 1 : the 8-hour area boundary and the 1-hour area boundary are identical. • Scenario 2 : he 8-hour area boundary is smaller than the 1-hour area boundary. • Scenario 3 : the 8-hour area boundary is larger than the 1-hour area boundary. • Scenario 4 : he 8-hour area boundary partially overlaps the 1-hour area boundary. 4. Q. Do 8-hour areas with 1-hour budgets have to use the 1-hour budgets for conformity determinations under the 8-hour standard? A. Yes, in most cases. As required in §93.109(e)(2) of the July 2004 final rule, the 1- hour budgets must be used for 8-hour conformity determinations, unless the interim emissions test(s) is more appropriate as decided through the interagency consultation process (see §93.109(e)(2)(v)). Section 176(c) of the Clean Air Act states that transportation activities must not cause new violations, increase the frequency or severity t tpage 27 of

ex isting viol at ions, ordel ay timely at tainment. Us ing 1- ho ur b udget s where avai lable and ap propriate ensures that air qua lity p rogress to date is main ta in ed, air qua lity will n ot be worsened and atta inme nt of the 8-hour standard w ill n ot be de laye d because of em issions in creases pr ior to th e dev elo pmen t of SIPs wi th

8- ho ur budget s. Once E PA finds a budget adequat e orappr ov es th e SIP t h at in cludes it, th e budget test pr ovid es the best mean s to det ermin e whet her tr an sportation plan s and T IPs meet Clean Air Act conformity r equire me nts. EPA be lie ves this pr in ciple app lie s with respect to the 1-hour b udget s in 8- ho ur nonattainment areas as well: in most cases , th e 1- ho ur b udget s are t he best test fordet ermining co nformity to th e 8- ho ur st andar d before 8- ho ur b udget s ar e avai labl e becaus e th e 1- ho ur b udget s have le d t o current ai rquality improvements.

5. Q. Ar e t h ere ci rc um st ances under which an 8- ho ur area wi th

1- ho ur b udget s would n ot use t h em? As des cribe d i n th e pream bl e t o th e J u ly 2004 f inal rule ( 69 F R 40025) , tho ugh EPA an ti cipat es th at except ions to th e use o f th e 1- ho ur budget s w ill b e infr equent, there are some cases where us ing t h e i nterim em issions test(s) may be more appr opri ate t o meet Clean Air Act require me nts. EPA expects such limit ed cases to be s uppo rt ed an d document ed i n th e 8- ho ur co nformity det ermin at ion fora gi ven area. EPA notes th at an adequat e orappr ov ed 1- ho ur SIP budget can not be co nsid ered i n appr opri ate s imply b ecaus e it is di ffi cul t to pas s for8- ho ur co nformity purpo ses. In addi tion, as note d b elow and co nsistent wi th

pas t co nformity preceden t, 1- ho ur b udget s can not be di s carded s imply b ecaus e th ey are b ase d o n ol der plan ning as sumptions orem issions mo del s, unless thro ugh in

teragenc y c onsultation it is determin ed that a di ffe rent e mis sions test(s) is mo re appr opri ate t o en sure th at ai rquality is not wo rs ened f orall 8- ho ur areas and t h at re duct ions are achieve d i n

certain ozon e areas . Th e most lik el y

example o f when th e 1- ho ur budget s may not be th e most appr opri ate t est is where a 1- ho ur b udget is not currently used i n

co nformity det ermin at ions for th e 1- ho ur st andar d, and t h us is currently not relie d upo n to measure whet her tr an sportation act ivities are co nsistent wi th

Clean Air Act re qui rements. Su ch a case would h a ppen when th e 1- ho ur b udget year is no long er in th e t imefr ame o f th e t r an sportation plan and t h ere i s no re qui rement to meet th e budget test pr ior to th e year in which th e n ext 1- ho ur b udget is es tablishe d, (e.g., th e SIP es tablishe d a budget for th e 1- ho ur at tainment ye ar , but th at at tainment year has pas se d and budget s for future year s are avai labl e) . Forexample, s uppo se a 1- ho ur maintenan ce area at tain ed i n

1999 and h as a maintenanc e plan wi th b udget s for2009. If th e area h as an 8- ho ur at tainment dat e of 2007, foran 8- ho ur co nformity det ermin at ion it would h ave to co mp are em issions in 2007 t o th e budget s from th e most r ecen t pr ior year , which would b e th e 1- ho ur at tainment b udget s for th e year 1999. In this case, th e budget s are n ot currently in use f or th e 1- ho ur st andar d, and i t may be more appr opri ate f oran area t o use t h e 2002 b aselin e year test for th e 2007 anal ysis year in th e 8- ho ur co nformity det ermin at ion, sin ce t h e 2002 b aselin e could b e lo wer an dpage 28 th eref or e more pr ot ect iv e t h an th e 1999 budget s. Howev er, th e maintenanc e area woul d use i ts 2009 budget s in th e 1- ho ur maintenan ce plan to show8- ho ur co nformity for2009 and all future anal ysis year s. Howev er, if th e budget year has pas se d b ut th e budget s have co ntin ued t o be used f or co nformity for th e 1- ho ur st andar d, th ey would lik el y

co ntin ue t o appl y for8- ho ur co nformity. Forexample, s uppo se a s evere 1- ho ur nonattainment area h as b udget s only for its 2005 at tainment year . Once t h e 8- ho ur st andar d applies and b efore th e area h as adequat e orappr ov ed 8- ho ur b udget s, th e area would lik el y

co ntin ue t o use i ts 1- ho ur at tainment b udget s forall anal ysis year s for8- ho ur co nformity det ermin at ions, even af ter th e year 2005 i s no long er in th e t imefr ame o f th e t r an sportation plan

. No te, al tho ugh the 2005 budget s would b e used af ter2005 i s no long erin th e t imefr ame o f th e plan , 2005 would n o long er be a r e qui re d anal ysis year . Anotherexample o f when th e i nterim em issions test(s) would b e more appr op ri ate t h an ex isting adequat e orappr ov ed 1- ho ur b udget s would b e in certain Scenar io 4 areas wher e it is impossibl e t o det ermin e which po rtion of a 1- ho ur b udget co vers an 8- ho ur nonattainment area. In this case, appl ying th e budget test wi th

1- ho ur b udget s is not f eas ible, and co ns equen tly, only th e i nterim em issions test(s) are avai labl e f or su ch uni que areas . As des cribe d i n

Sect ion V. of th e J u ly 1, 2004, pream bl e (69 F R 40019 - 21) , when a SI P b udget is not es tablishe d a mo der ate orab ov e o zon e area would need t o pas s both interim em issions tests. Ar eas clas sifi ed as margin al ordes i gnated under Clean Air Act, Part D, subp art 1 can ch oos e b etw een th e t wo tests when no b udget s appl y. Howev er, in th es e cases where a 1- ho ur b udget is avai labl e b ut th e area demonstr ates it is not th e most appr opri ate t est, EPA believes th at th e n o-gr eater -than- 2002 b aselin e ye ar test woul d mo st lik el y b e used. EPA be lie ves it is extremel y unlik el y t hat the bu ild /no-bu ild test alone would ever be a more appr opri ate t est th an th e budget test wi th

ex isting 1- ho ur b udget s th at are currently used f orco nformity purpo ses. Please r efer to th e J uly 1, 2004, rule pream bl e o n this po int ( 69 F R 40025)

. Ar eas mu st use t h e co ns ul tation pr o ces s to decide whet her th e appli cab le interim em issions tests are more appr opri ate t o meet Cl ean Air Act re qui rements th an th e budget s in

each 1- ho ur SIP. As des cribe d i n th e f irst example ab ov e, th ere may be cases where an area h as multiple 1- ho ur SIPs , some of which have appr opri ate budget s while others do not. In areas where o nly on e i nterim em issions test may be sel ected, th e rule re qui res th at areas must al so justify sel ect ion of th e s p eci fi c t est ch os en as being more appr opri ate f or meet ing C l ean Air Act re qui rements th an th e avai labl e 1- ho ur b udget s. This deci sion should be di sc us se d wi th

all intera gen cy co ns ul tation parties and document ed i n the co nformity det ermin at ion for th e 8- ho ur st andar d. (Ple ase r efer to th e pream bl e o f the July 2004 f inal co nformity rule at 69 F R 40025 f or more informat ion.)page 29 6. Q. In 8- ho ur areas wi th

1- ho ur subar ea budget s, do all subar eas have to use t h e 1- ho ur b udget s for8- ho ur co nformity det ermin at ions? Li kewi se, in multi-st ate 8- ho ur areas where each st ate h as se par ate 1- ho ur b udget s, do all st ates have to use t h ei r1- ho ur b udget s for8- ho ur co nformity? A. In gen eral, each su bar ea o r st ate can det ermin e co nformity in depen d en tly as long as everyone is us ing 1- ho ur b udget s to det ermin e co nformity. Howev er, in th e unlik el y even t th at on e s ubar ea o r st ate det ermin es th at its 1- ho ur b udget s are i n appr opri ate, other subar eas or st ate budget s may al so be in appr opri ate. See Part 3 o f this guidance f or further ration ale f orco nformity det ermin at ions us ing s ubar ea and m ulti-st ate SIP budget s. Wh en an y subar ea o r st ate b elieves th at is in appr opri ate t o use i ts b udget s, all subar eas or st ates would co ns ul t to det ermin e t h e i mp act on future co nformity det ermin at ions. EPA believes th at where o n e s ubar ea o r st ate det ermin es its b udget s are i n appr opri ate, it is lik el y th at th e o ther b udget s are al so in appr opri ate becaus e th ey are co ll ect iv el y intend ed to addres s th e s ame Cl ean Air Act purpo se. EPA notes, ho wev er, th at in a Scenar io 4 area, th e ci rc um st ances are di fferent and more co mp lex. In th ese areas , th e 8- ho ur area partially ov er la ps th e 1- ho ur area. In a m ultiple MP O o r multi-st ate Scenar io 4 area, it may be th e case t h at on e o r more other MP Os or st ates can not use t h ei r1- ho ur b udget s b ecaus e it is not po ssibl e t o det ermin e what po rtion of th e budget s appl y. Howev er, other MP Os or st ates may st ill b e ab le to use their 1- ho ur b udget s for th ei rpo rtions of th e 8- ho ur area. See b elo w f or further informat ion on th e v arious s cenar ios.

7. Q. In an 8- ho ur area wi th

a 1- ho ur SIP t h at es tablishes subar ea budget s, ho w s hould MP Os demonstr ate co nformity for th e f irst time under th e 8- ho ur st andar d? A. As des cribe d i n

Part 3 o f this guidance, when an area h as su bar ea budget s, co nformity foran MP O’ s plan and T IP can only be det ermin ed i f all other subar eas have co nforming tr an sportation plan s and T IPs in place f ora gi ven po llutant and s t andar d. To th e extent po ssibl e, EPA believes th at th e s u bar ea budget s must be used i n th e 8- ho ur conformity d etermin at io n, unle ss it is determin ed through consultation that they are not appr opri ate f or meet ing C l ean Air Act co nformity re qui rements. Sub ar ea budget s in 1- ho ur SIPs must co ntin ue t o be used under th e co nformity rule for th e 8- ho urst andar d, b ecaus e th ey en sure th at ai rquality pr ogress to dat e is maintain ed. In

gen eral, where an 8- ho ur area h as mu ltiple MP Os wi th subar ea budget s for th e 1- ho ur standard, EPA and DOT be lie ve it is necessary fo r the fir st conformity d etermin at io n under th e 8- ho ur st andar d to be do ne as follo ws : each MP O would s how its plan and T IP co nform to its 1- ho ur subar ea budget s in depen d en tly. All of th e M P Os ’ plan/T IP conformity d etermin at io ns would then be sub mit ted to DOT fo rit s determin at io ns. DOTpage 30

w ill n ot mak e it s conformity d etermin at io n on an y o f the plans or TIPs fr om the 8-hour area un til

every MP O i n th e area h as ma de a co nformity det ermin at ion for its plan an d TIP. Pl ease n ote th at this an sw er may di ffer for S cenar io 3 and 4 areas where an addi tion al po rtion of th e 8- ho ur area i s not co vere d b y th e 1- ho ur b udget s (these Scenar ios are di sc us se d l ater in this part, be gi nning wi th

Q & 14) . All MP Os in th e 8- ho ur area mu st have an initial v a lid conformity d etermin at io n fo r the 8-hour standard by the end of th e o n e- year grace per iod. If an y

do not, DOT w ill b e unab le to make an y 8 -hour co nformity det ermin at ions for th e 8- ho ur area, and all of th e M P Os ’ plan s and T IPs wi ll la

pse.

8. Q. How are s ubs equen t 8- ho ur co nformity det ermin at ions ma de i n

an 8- ho ur area wher e th e 1- ho ur SIP es tablishes subar ea budget s? A. In g enera l, once DOT has ma de it s initial 8 -hour conformity d etermin at io n fo r the area, the MPOs w ill o perate as usua l: be fo re an y M PO in the area determin es conformity u s ing subar ea budget s, all other MP Os in th e area m ust have a co nforming plan and T I P i n place. If on e s ubar ea i s in a co nformity la pse, co nformity det ermin at ions for ne w o r revise d plan s and T IPs can not be ma de i n other subar eas un til th e l a pse ends . This an sw er may di ffer for S cenar io 3 and 4 areas where an addi tion al po rtion of th e 8- ho ur area i s not co vere d b y th e 1- ho urb udget s (dis cus se d l ater in this part, be gi nning wi th

Q &A 14)

.
S cenar io 1 A r eas 9. Q. How i s co nformity demonstr ated i n

Scenar io 1 areas when th e 1- ho ur SIP budget s appl y to th e en tire 1- ho ur area? A. Us ing 1- ho ur b udget s for8- ho ur co nformity det ermin at ions is straig htforw ard i n S cenar io 1 areas , b ecaus e th e b o undar i es of th e 8- ho ur area and 1- ho ur area( s) are exact ly the same . The MPO or MPOs mu st coordinate their plan/TIP conformity d etermin at io ns and s ubmit th em to DOT

. Once DOT r ecei ves all plan /TIP co nformity det ermin at ions for the 8-hour area, DOT w ill make it s conformity d etermin at io ns at the same t ime . If there is mo re than one MPO, the planning agencies w ill h ave to work together to deve lo p one re gi on al em issions anal ysis for th e en tire 8- ho ur area under §93.109(e) (2)(i), just as th ey would h ave b een do ing f or th e 1- ho ur st andar d. Please see Part 3 o f this guidance f or further informat ion re gar ding h o w a r e gi on al em issions anal ysis could b e co mplete d f or th ese areas . No te th at a Scenar io 1 8- ho ur area could b e formed f rom on e o r more 1- ho ur areas wi th adequat e orappr ov ed 1- ho ur b udget s for th e en tire 8- ho ur area.page 31 10. Q. How i s co nformity demonstr ated i n S cenar io 1 areas when th e 1- ho ur SIP in cludes su

bar ea budget s? A. As discussed in Part 3, Q & A 1, conformity follows the SIP. Th erefore, conformity and t h e suppo rting r e gi on al em issions anal ysis is do ne for th e geo gra phic area t h at is co vere d b y th e S IP’s b udget s, i. e. , each subar ea’ s po rtion of th e n onattainment area. See Part 3, Qs & As 5 - 7, and Qs & As 7 and 8 o f this part foraddi tion al informat ion.

11. Q. How i s co nformity demonstr ated i n mu lti-st ate Scenar io 1 areas , where each st ate h as its own se par ate 1- ho ur SIP budget s? A. As discussed in Part 3, Q & A 1, conformity follows the SIP. Th erefore, conformity and t h e suppo rting r e gi on al em issions anal ysis is do ne for th e geo gra phic area t h at is co vere d b y th e S IP’s b udget s, i. e. , each st ate’ s po rtion of th e n onattainment area. Before 8- ho ur ozon e budget s are f o und adequat e orappr ov ed, EPA co ncl udes th at wher e each st ate h as its own 1- ho ur b udget s, each st ate can co ntin ue t o demonstr ate co nformity to its SIP in depen d en tly for th e 8- ho ur ozon e s t andar d. Th eref or e, co nformity det ermin at ions for th e 8- ho ur st andar d can be ma de i n on e s t ate o f a m ulti-st ate 8- ho ur area even if

a l a pse i s o ccurring in an other st ate i n th e 8- ho ur area, orco nformity ha d n ot yet b een det ermin ed f or th e 8- ho ur ozon e s t andar d in an other st ate i n th e area. This in depen d ence i n

a m ulti-st ate 8- ho ur area applies as long as all st ates are us ing 1- ho ur b udget s to det ermin e co nformity. Please see Part 3 o f this guidance f or further informat ion re gar ding h o w a r e gi on al em issions anal ysis could b e co mplete d f or th es e areas .
S cenar io 2 12. Q. How i s co nformity demonstr ated i n S cenar io 2 areas , when th e 1- ho ur SIP es tablishes b udget s th at appl y to th e en tire 1- ho ur area? A. Regar d less of whet her th e area i s lo cated en tirely wi thin on e s t ate, or is a m ulti-st at e area, th e M P O o r MP Os mu st co or di nate plan /TIP co nformity det ermin at ions and s ubmit th em to DOT to satisfy th e co nformity ru les. Once DOT r ecei ves all plan /TIP co nformity determin at io ns fo r the 8 -hour or 1-hour area (as app lic ab le ), DOT w ill make it s co nformity det ermin at ions at th e s ame time. Pl ease see P art 3 o f this guidance f or further informat ion re gar d ing h o w a r e gi on al em issions anal ysis could b e co mplete d f or th es e areas . [ ans wer continues next page]page 32 These areas can choose either of two versions of the budget test, as required by §93.109(e)(2)(ii): • the budget test using the subset or portion of existing adequate or approved 1-hour budgets that cover the 8-hour area, where such portion can be appropriately identified (§93.109(e)(2)(ii)(A)); or • the budget test using the existing adequate or approved 1-hour budgets for the entire 1-hour area, however in this case any additional emissions reductions needed to pass the budget test must come from within the 8-hour area (§93.109(e)(2)(ii)(B)). The interagency consultation process should be used to determine whether budgets for the 8-hour area can reasonably be derived from the 1-hour budgets. It may be possible to create budgets for only the 8-hour area, for example if the 1-hour SIP contains estimates of emissions by county in the years for which budgets are established, and emissions from the county or counties not included in the 8-hour area can be subtracted from the 1-hour budgets. In Figure 6 below: Budget for 8-hour area 1-hour budget – county or counties not in the 8-hour area (Area in the bold line) = (emissions in the – (emissions from gray circle) the crescent shape)

If is not possible to create budgets that apply to only the 8-hour area, the MPO or MPOs will have to determine conformity to the 1-hour b udgets for 8-hour conformity as they have for the 1-hour standard, and if reductions are needed to meet the budgets, they must come from within the 8-hour area (inside the bold line in Figure 6) as required by the conformity rule. =page 33 Note that a Scenario 2 8-hour area could be formed from one 1-hour area as in Figure 6 above, or more than one 1-hour area with adequate or approved 1-hour budgets for the 8- hour area, as depicted in Figure 7, below. In these cases, consultation should be used to determine how the 1-hour budgets w ill apply.

13. Q. How is conformity demonstrated in multi-state Scenario 2 areas, where each state has its own separate 1-hour SIP budgets? A. As discussed in Part 3, Q & A 1, conformity follows the SIP. Therefore, conformity is determined for the geographic area that is covered by the SIP’s budgets, i.e., each state’s portion of the nonattainment area. Before 8-hour ozone budgets are found adequate or approved, EPA concludes that where each state has its own 1-hour budgets, each state can continue to demonstrate conformity to its SIP independently for the 8-hour ozone standard. Therefore, conformity determinations for the 8-hour standard can be made in one state of a multi-state 8-hourarea even if a lapse is occurring in another state of the area. This independence in a multistate area applies as long as all states are using 1-hour budgets to determine conformity. For these Scenario 2 8-hour areas, each state can choose either of two versions of the budget test: • the budget test using the subset or portion of existing adequate or approved 1-hour budgets that cover the 8-hour area within its state, where applicable and when such portion can be appropriately identified (§93.109(e)(2)(ii)(A)); or • the budget test using the existing adequate or approved 1-hour budgets for the portion of the 1-hour area within its state, however in this case any additional emissions reductions needed to pass the budget test must come from within that state’s portion of the 8-hour area (§93.109(e)(2)(ii)(B)).page 34 Scenario 3 Areas Within One State 14. Q. How is conformity demonstrated in a Scenario 3 area located entirely within one state, when the 1-hour SIP establishes budgets that apply to the entire 1-hour area? A. In this case, the conformity rule requires that the MPO or MPOs must work together to apply the 1-hour budgets to the portion of the 8-hour area covered by them. An 8-hour area whose boundary is larger than the 1-hour area boundary includes one or more new counties that were not covered by the 1-hour standard. According to §93.109(e)(2)( iii), conformity can be determined for the 1-hour area by using the 1-hour budgets for that portion of the 8-hour area covered by them, plus the interim emissions test(s) for either: • the remaining portion of the 8-hour area (the new county or counties), or • the entire 8-hour area. In Figure 8 below, the budget test must be used for the gray portion of the area, and the interim emissions test either for the white portion of the 8-hour area, or the entire 8-hour area.page 35 15. Q. How is conformity demonstrated in a Scenario 3 area located entirely within one state, when the 1-hour SIP establishes subarea budgets that apply for each MPO? A. As described in Part 3, Q& As 5 - 7, and in Q & As 6 - 8 of this part, each MPO can develop its own regional emissions analysis and conformity determination for its plan and TIP, as long as all of the other MPOs in the area have a conforming plan and TIP in place The twist for a Scenario 3 area is that there is a portion of the 8-hour area that is not covered by 1-hour budgets. For this portion of the 8-hour area, a regional emissions analysis using the interim emissions test(s) must be done for either:

< the part of the 8-hour area not covered by 1-hour budgets, or
< the entire 8-hour area. As addressed in Q & A 7 of this part, for the initial conformity determinations under the 8- hour standard, each MPO can determine conformity for its own plan and TIP and DOT will wait to r eceive a conformity determination for each MPO before making its conformity determination for the plans and TIPs in the area.

In Figure 9, above, MPOs A, B, C, and D can develop conformity determinations for just their own plans and TIPs using their 1-hour subarea budgets. The regional emissions analysis for Part E must be done using the interim emissions test(s), according to §93.109(e)(2)( iii)(B) of the conformity rule. Part E may be a donut area or may have its own MPO. If Part E is a donut area, per §93.105(c)(3) of the rule, the parties involved in interagency consultation must discuss which agency will be responsible for Part E’s regional emissions analysis, and for what geographic area it will be done. DOT would wait until it had conformity determinations for all MPO plans/TIPs and the donut area before making its initial conformity determinations for the 8-hour standard.page 36 S cenar io 3 Mu lti-St ate A r eas 16. Q. How i s co nformity demonstr ated i n multi-st ate Scenar io 3 areas , where all of th e s t ates have their own separate 1-hour SIP budgets? A. As des cribe d ab ov e, co nformity det ermin at ions can co ntin ue t o be ma de i n depen d en tly in

each st ate t h at has se par ate 1- ho ur b udget s, as long as all st ates in th e area use t h ei r resp ect iv e 1- ho ur b udget s for th ei r8- ho ur co nformity det ermin at ions. In addi tion, if the 8- ho ur bo undary in a s t ate i s larg er th an th e 1- ho ur bo undary in th at st ate, th e i nterim emi ssi on s t e st (s) mu stbe met for either:

• the po rtion ou tsid e t h e 1- ho ur bo undary and i nsi de t h e 8- ho ur bo undary in th at st ate, • that st ate’ s en tire po rtion of th e 8- ho ur nonattainment area, or • the en tire mu lti-st ate 8- ho ur area. 7 Th e pr ovision of th e rule th at re qui res th e i nterim em issions test(s) in S cenar io 3 areas , §93.109(e) (2)( iii)(B), could appl y to an y of th ese t hre e geo gra phic ch oi ces . Forexample, in Fi gure 10 b elo w, an 8- ho ur nonattainment area i n cludes parts of three st ates . Th e 8- ho ur bo undary in States A and B is unchanged f rom th e 1- ho ur bo undary, but th e 8- ho ur bo undary in St ate C i s larg er . St ates A, B, and C can co ntin ue t o det ermin e co nformity in depen d en tly from on e an other for th e 8- ho ur st andar d as follo ws : • States A and B would det ermin e co nformity by meet ing t h ei r1- ho ur b udget s.

• State C would det ermin e co nformity by meet ing i ts 1- ho ur b udget s, plus the in

ter im emis sions test(s) eitherfo r: < th e po rtion in State C not co vere d b y th e 1- ho ur b udget s (in Fi gure 10, the whit e p ort io n in side the bo ld lin e),
< th e en tire po rtion of th e 8- ho ur area i n St ate C, or < th e en tire multi-st ate area ( s ee f ootnote 7)

.

7 Tho ugh th e i nterim em issions test(s) could b e do ne for th e en tire 8- ho ur nonattainment area under th e f inal rule, as explai ne d i n th e pream bl e (69 F R 40023) , “doing so may not allow each MP O i n this example t o dev elo p t r an sportation plan s and T IPs and co nformity det ermin at ions in depen d en tly.” Pl ease co ns ul t wi th EPA and DOT to di sc us s th e i mpli cat ions for all st ates before ch oosing t his option.page 37

17. Q. How is the regional emissions analysis done in multi-state Scenario 3 areas, where only one of the states has its own 1-hour SIP budgets? A. Consistent with Clean Air Act section 176(c), EPA interprets §93.109(e)(2)( iii) of the conformity rule to mean that a state can determine conformity completely independently, even if it is the only state in the 8-hour area that has 1-hour budgets. If one state has 1- hour budgets and the 8-hour area is a two-state area, then both states can determine conformity on their own: • the state with the 1-hour budgets would continue to use them for 8-hour conformity; • the state without budgets would use the interim emissions test(s). In Figure 11 below, each state can determine conformity for its own portion of the 8-hour area, even though State B does not have 1-hour budgets.

However, if the 8-hour area was a three-state area and only one state had 1-hour budgets, only the state with the budgets could determine conformity on its own. The other two states would determine conformity for the 8-hour standard together using the interim emissions test(s).page 38 S cenar io 3 – Gen eral 18. Q. Wh at are t h e s p ecial issu es th at th e i ntera gen cy co ns ul tation pr o ces s should co nsid er in S cenar io 3 areas ? A. Th e i ntera gen cy co ns ul tation pr o ces s is of key imp ortan ce i n th ese areas . Becaus e the 8- ho ur area i s larg er th an th e 1- ho ur area, on e o r more plan ning agencies prev io us ly not involv ed i n

co nformity may b eco me part of th e i ntera gen cy pr o ces s. Th ese plan ning agencies n eed t o be in cluded i n th e deci sion-maki ng pr o ces s for th e area. Thro ugh th e i ntera gen cy co ns ul tation pr o ces s as re qui re d b y §93.105 o f th e co nformity ru le , the in vo lv ed part ie s mu st decide:

• whe th erto a p ply th e in te rim emissi on s te st(s) to th e en ti

re 8-hour area (or in a multi-st ate area where o n e o r more of th e s t ates have 1- ho ur b udget s, to one st ate’ s en tire po rtion of th e area) or just th e po rtion not co vere d b y th e 1- ho ur b udget s;

• wheth er it is more appr op ri ate f or th e s t ate DOT oran MP O t o prepare t he re gi on al em issions anal ysis fora do nut area, if th ere i s on e;

• which in ter im emis sions test w ill b e u sed, in areas permit ted to se le ct only o ne test; an d

• analysis year s for th e budget test and i nterim em issions test(s). It may be po ssible to ch oos e anal ysis year s th at satisfy both th e budget and i nterim em issions test re qui rements in §§93.118(d) (2 ) and 93.119(g) , as des cribe d b elo w.

S cenar io 4 A r eas Within One S t at e 19. Q. How i s co nformity do ne in a Scenar io 4 area, when 1- ho ur b udget s appl y to th e en tire 1- ho ur area, th at is, th e SIP does not es tablish subar ea budget s? A. It may be po ssibl e t o use t h e budget s from th e 1- ho ur SIP, if th e SIP i n cludes em issions by coun ty

and i t is po ssibl e t o det ermin e which po rtions of th e 1- ho ur b udget s appl y to th e 8- ho ur area. In this case, th e 8- ho ur area would s howco nformity in a manner s imilar to a Scenar io 3 area. It wou ld use:

• the relevant po rtion of th e 1- ho ur b udget s for th e po rtion of th e 8- ho ur area wher e it has th em , plus

• the in ter im emis sions test(s), eitherfo r: < th e r emaining po rtion of th e 8- ho ur area, or < th e en tire 8- ho ur area.page 39

8 This statement does not preclude agencies from developing a reasonable way to utilize the 1-hour budgets, via the interagency consultation process where possible. The final conformity rule requires the use 1-hour budgets where ever it is appropriate and possible. For example, in Figure 12 below, if it is possible to determine what portion of the 1-hour budgets apply for the portion of the 1-hour area that is now inside the 8-hour area boundary, the area would use: • the budget test, for that portion of the 8-hour area that has them (as indicated by the arrow in Figure 12), and • the interim emissions test(s) must be met for either:
< the part of the 8-hour area not covered by budgets – n Figure 12, the portion shaded with the pattern, or
< the entire 8-hour area.

However, it may not be possible for the 8-hour area to use the 1-hour budgets at all. This outcome would occur, for example, if 1-hour SIP does not include an emissions inventory by county. It could also occur if the 8-hour boundary includes and excludes portions of counties instead of entire counties. The interagency consultation process would be used to discuss use of 1-hour budgets in Scenario 4 areas. When such cases occur, a Scenario 4 area would determine conformity using the applicable interim emissions test(s) for the entire area. 8

Scenario 4 Multi-State Areas 20. Q. How does a multi-state Scenario 4 area determine conformity when the 1-hour SIPs have separate budgets that apply to each state? A. As described above, multi-state Scenario 4 areas are a unique case. Where each state has separate 1-hour budgets that apply only to its portion of the nonattainment or maintenance area, each state in a multi-state Scenario 4 area can operate entirely independently. Where a state’s portion can use its 1-hour budgets, it must use them ipage 40

acco rd ing t o §93.109(e) (2)(iv) of th e rule. Any po rtion of a s t ate’ s area n ot co vere d b y th e budget s would h ave to be in cluded i n

an interim em issions test(s), for: • that part not co vere d b y 1- ho urb udget s, • the st ate’ s en tire po rtion of th e 8- ho ur area, or • the en tire 8- ho ur area. Th e co ns ul tation pr o ces s would b e used t o det ermin e which test op tion is sel ected i n S cenar io 4 areas

.
21. Q. How i s th e r e gi on al em issions anal ysis do ne in a m u lti-st ate Scenar io 4 area, wher e only on e o f th e s t ates has its own 1- ho ur SIP budget s? A. EPA interp rets §93.109(e) (2)(iv) to mean th at if an y st ate i n th e 8- ho ur area h as 1- ho ur b udget s, th at st ate can det ermin e co nformity co mpletely in depen d en tly from the other st ates in th e 8- ho ur area. Th e s t ate o r st ates th at have 1- ho ur budget s woul d co ntin ue t o use t h em orpo rtions of th em as appr opri ate, to th e extent po ssibl e, for th ei r8- ho ur re gi on al em issions anal ysis and co nformity det ermin at ion. Th e s t ate o r st ates wi thout 1- ho ur SIP budget s would use t h e i nterim em issions test(s) for8- ho ur co nformity; if th ere i s more th an on e s t ate i n th e area wi thout 1- ho ur b udget s, th ese s t ates would determin e conformity t ogether.

22. Q. Wh at are s p ecial issu es th at th e i ntera gen cy co ns ul tation pr o ces s should co nsid er in S cenar io 4 areas ? A. As in S cenar io 3 areas , th e i ntera gen cy co ns ul tation pr o ces s is of key imp ortan ce i n S cenar io 4 areas . Wh ere an 8- ho ur area partially ov er la ps a 1- ho ur area, on e o r more MPOs may n o lo nger have to determin e conformity, and one ormo re new MPOs may b eco me part of th e i ntera gen cy pr o ces s. All MP Os in th e 8- ho ur area as well as th e o ther parties involv ed i n intera gen cy co ns ul tation n eed t o be involv ed i n th e deci sion-maki ng pr o ces s for th e area. Thro ugh th e i ntera gen cy co ns ul tation pr o ces s as re qui re d b y §93.105 o f th e co nformity ru le , the in vo lv ed part ie s mu st decide:

• wheth er to appl y th e i nterim em issions test(s) to th e en tire area ( or in a m u lti-st at e area, to on e s t ate’ s po rtion of th e area) or just th e po rtion not co vere d b y th e 1- ho urb udget s;

• wheth er it is more appr op ri ate f or th e s t ate DOT oran MP O t o prepare t he re gi on al em issions anal ysis fora do nut area, if th ere i s on e;

• which in ter im emis sions test w ill b e u sed, in areas permit ted to se le ct only o ne test; an dpage 41

• analysis year s for th e budget test and i nterim em issions test(s). It may be po ssible to ch oos e anal ysis year s th at satisfy both th e budget and i nterim em issions test re qui rements in §§93.118(d) and 93.119(e) of th e ru le, as des cribe d b elo w.

Genera l I mp lementation of Fina l R u le 23. Q. Wh at precur sors must be exam in ed i n

8- ho ur areas wi th

1- ho ur b udget s? A. As des cribe d i n th e pream bl e t o th e J u ly 1, 2004, final tr an sportation co nformity rule th e r e gi on al em issions anal ys es for ozon e areas must addres s th e o zon e precur sors nitrog en oxid es ( NOx) and v olatile or gani c co mpounds ( VOC ) ( §93.102( b)(2)(i)). In cases where budget s are used, co nformity is demonstr ated wi th th e budget test for adequat e and appr ov ed NOx and VOC b udget s ( §93.118) . In all cases where areas us e the interim emi ssi on s t e st (s), both precursor s m u stbe analyzed unle ss E PA i ssu es a NOx wai v er for th e 8- ho ur st andar d foran area underCl ean Air Action s ect ion 182( f). Th es e re qui rements are co nsistent wi th th e co nformity rule to dat e, al tho ugh th e J uly 2004 f inal rule moves th ese pr ovisions to §93.119( f) due t o reor ganizat ion of §93.119. Ar eas must also co mple te the in ter im emis sions test(s) fo r NOx if t he only S IP ava ila ble is a r eas on ab le furtherpr ogress SIP forei th er th e 1- ho ur or8- ho ur st andar d th at co nt ai ns a b udget forVOC s only (e.g., a 15% SIP)

. See §93.109(e) (3) of th e f inal rule for further info rmat io n. 24. Q. How i s th e budget test gen erally imp lement ed i n

8- ho ur areas wi th

1- ho ur b udget s? A. Th e budget test re qui rements in §93.118 f or8- ho ur areas w ill b e g enera lly implement ed i n th e s ame manneras in 1- ho ur areas , wi th

a f e w except ions. First, as des cribe d ab ov e, th e geo gra phic area co vere d b y th e 8- ho ur st andar d may be di fferent th an th at co vere d b y th e 1- ho ur st andar d and SIP budget s in some cases . Seco nd, the year s forwhich re gi on al mo deling i s re qui re d ( i.e., anal ysis year s) may di ffer. Ar eas th at use 1- ho ur b udget s for th ei r8- ho ur co nformity det ermin at ions w ill n eed to det ermin e t h e mo deling anal ysis year s th at appl y for th e 8- ho ur st andar dper §93.118(d)

. Under this sect io n, a mo de ling anal ysis mu st be co mple ted fo r: • the last year of th e t r an sp ortation plan , • the at tainment year for th e r elevant po llutant and s t andar d, an d • an intermedi ate year (s) su ch th at anal ysis year s are n ot more th an 10 ye ar s apart. Th e at tainment year anal ysis is to be foran area’ s at tainment year for th e 8- ho ur st andar d , whic h probab ly will b e di ffe rent than the atta inme nt ye ar under the 1-hour standard. Thepage 42

area m u st th en calcul ate em issions in th e anal ysis year s from th e plan ne d t r an sportation syst em. Once mo deling i s co mp lete d per §93.118(d) (2), 8- ho ur areas us ing 1- ho ur SIPs w ill a lso demonstr ate co nsistency wi th th e 1- ho ur b udget s acco rding t o §93.118( b), except for cases where i t is det ermin ed t h at 1- ho ur b udget s are n ot appr opri ate t hro ugh the co ns ul tation pr o ces s as des cribe d ab ov e and i n

§93.109(e) (2)(v) of th e co nformity rule. A cco rding t o §93.118( b) th e J uly 1, 2004, final rule, co nsistency wi th

1- ho ur b udget s mu stbe sh own for: • all 1- ho ur b udget year s th at are wi thin th e t imefr ame o f th e t r an sp ortation plan , • t he8

- ho ur attainme ntyear, • the last year of th e plan , an d • an intermedi ate year (s) so th at all year s are n ot more th an 10 year s apart. Emissions pr oj ected f oreach anal ysis year mu st be wi thin th e budget s in th e 1- ho ur SIP from th e most r ecen t pr ior year . Interpol at ion can be used b etw een anal ysis year s for demonstr at ing co nsistency wi th b udget s, just as has b een do ne under th e 1- ho ur st andar d. Forexample, s uppo se an area des i gnated n onattainment for th e 8- ho ur ozon e s t andar d wi th

an 8- ho ur at tainment dat e of 2010 has th e f ollo wi ng 1- ho ur b udget s:

• 2005 r ate-of- pr og ress (R OP) b udget s forNOx and VOC s, • 2007 R O P budget s forNOx and VOC s, an d • 2007 at tainment b udget s forNOx and VOC s. By 2005, this area would det ermin e co nformity for its 2005-2025 t r an sp ortation plan an d its TIP, and t h e co nformity det ermin at ion would b e acco mplishe d as follo ws :

• 2005 budget test, us ing t h e 2005 R O P budget s; • 2007 budget test, us ing b oth 2007 R O P and at tainment b udget s; • 2010 budget test, us ing t h e 2007 at tainment b udget s 9 ; • 2020 budget test, 10 us ing t h e 2007 at tainment b udget s; an d • 2025 budget test, us ing t h e 2007 at tainment b udget s. As des cribe d i n

§93.118(d) (2 ), em issions for th e ye ar 2005 could b e gen erate d wi th a re gi on al em issions anal ysis, orcould b e interpol ated i f th e area h as run a r e gi on al

9 EPA has prev io us ly interprete d t h at only at tainment b udget s appl y beyond th e at tainment year , in cases where o zon e areas al so have b udget s for RO P SIPs

. 10 Th e year 2020 i s ch os en for this example, but an y year from 2015 t hro ugh 2019 woul d al so be accept abl e f or th e i nterim year anal ysis.page 43

em issions anal ysis foran ear lier year . Emissions for th e year 2007 could al so be interp ol ated o r th e area could ch oos e t o mo del em issions for this ye ar . A re gi on al mo deling anal ysis must be do ne for th e year 2010 ( the 8- ho ur at tainment year ), an y year betw een 2015 and 2020 f or th e i ntermedi ate year (in this example, 2020 i s the intermedi ate year ), and t h e year 2025 ( the last year of th e t r an sportation plan) as re qui red by §93.118(d)(2). As st ated ab ov e, on ce adequat e orappr ov ed 8- ho ur b udget s are es tablishe d f ora gi ven precur sor, th e budget test would b e co mp lete d wi th only th e 8- ho ur b udget s for th at precur sor, rath er th an th e 1- ho ur b udget s.

25. Q. Wh ere 8- ho ur areas have to use b oth th e budget test and t h e i nterim em issions test(s), what anal ysis year s would b e ch os en ? A. As des cribe d i n th e J u ly 2004 f inal rule, th ere w ill b e cases in Scenar io 3 or 4 areas where b oth th e budget and i nterim em issions tests are used. Sect ions 93.118 and 93.119 of th e co nformity rule co ver th e cr it er ia and pr o cedures for th e budget test and t h e i nterim em issions tests, resp ect iv el y. E ach of th ese sect ions def ine th e anal ysis ye ar s th at must be exam in ed i n th e partic ular test. In th e budget test, th e year s th at mu st be anal y

zed (§93.118(d) (2)) are: • t he8

- ho ur attainme ntyear, • the last year of th e t r an sp ortation plan , an d

• an intermedi ate year or year s as n eces sary, so th at anal ysis ye ar s are n o more th an ten year s apart. In th e i nterim em issions tests, th e year s th at mu st be anal y

zed (§93.119(g) ) are:

• a year no more th an five year s in th e f uture (from th e year in which th e co nformity determin at io n is ma de) • the last year of th e t r an sp ortation plan , an d

• an intermedi ate year or year s as n eces sary, so th at anal ysis ye ar s are n o more th an ten year s apart. Th e i ntera gen cy co ns ul tation pr o ces s can be used t o ch oos e anal ysis ye ar s th at meet the re qui rements of both §§93.118 and 93.119 s o th at th e n umb er of anal ysis ye ar s is minimized. Forexample, co nsid er a Scenar io 3 area i n on e s t ate t h at is clas sifi ed as mo der ate for th e 8- ho ur st andar d th at has 1- ho ur budget s for th e year s 2005 and 2007. This area needs to use b oth th e budget and i nterim em issions tests to det ermin e co nformity for th e 8- ho ur st andar d, b ecaus e th ere i s a po rtion of th e area t h at is not co vere d b y th e 1- ho ur b udget s. Th e plan co vers th e year s 2005 t hro ugh 2025 and t h e co nformity determin at io n w ill b e ma de in the ye ar 2005. This area could exam in e t h e f ollo wi ng anal ysis ye ars in it s 8-hour conformity d etermin at io n:page 44

• 2010 , whic h fulfills the §93.118 r e qui rement to anal y

ze t h e 8- ho ur at tainment year , and t h e §93.119 r e qui rement to anal y

ze a year no more th an five year s in the future;

• 2015 , whic h fulfills the require me nt in both ru le sect io ns to anal yz e an in termed iate year so th at anal ysis year s are n o more th an 10 year s apart; an d

• 2025 , whic h fulfills the require me nt in both ru le sect io ns to anal yz e the la st ye ar of th e plan

. In

addi tion, th e rule re qui res th at th e po rtion of th e area co vere d b y th e 1- ho ur b udget s must al so demonstr ate co nsistency wi th th e budget s for th e year s 2005 and 2007. Co nsistency can be demonstr ated us ing i nterpol at ion fora year betw een two anal ysis ye ar s as des cribe d i n

§93.118(d) (2) of th e co nformity rule. In this example, th e area could do a re gi on al em issions anal ysis for2005 and i nterpol ate em issions for2007 us ing t h e 2005 an d 2010 anal ys es . Altern at iv el y, th e area could i nterpol ate 2005 and 2007 em issions by us ing an anal ysis fora year before 2005 do ne for mo del valid at ion purpo ses, if su ch a year is not more th an 10 year s ear lier th an 2010 ( so th at anal ysis year s are n o more th an 10 year s apart). In this example, th e budget test and i nterim em issions test re qui rements would t h en be satisf ie d as follo ws:

• 2005: b udget test, us ing t h e 2005 budget s • 2007: b udget test, us ing t h e 2007 budget s

• 2010: b udget test, us ing t h e 2007 budget s and i nterim em issions test(s) for2010

• 2015: b udget test, us ing t h e 2007 budget s and i nterim em issions test(s) for2015 11

• 2025: b udget test, us ing t h e 2007 budget s and i nterim em issions test(s) for2025 As des cribe d i n

§93.109(e) (2 )( iii)of the Ju ly 1 , 2004, final rule, th e r e gi on al em issions anal ysis for th e budget test in Scenar io 3 would co ver th e 1- ho ur area po rtion of th e 8- ho ur area ( i.e., th e po rtion co vere d b y th e 1- ho ur b udget s). Th e r e gi on al anal ys es for the interim em issions tests in an area l o cated wi thin a s ingle st ate would co verei th er the po rtion of th e 8- ho ur area n ot co vere d b y th e 1- ho ur b udget s, or th e en tire 8- ho ur area. [

ans wer continues on the next page]

11 Th e year 2015 i s ch os en for this example, but an y year betw een 2016 and 2020 woul d al so be accept abl e f or th e i nterim year anal ysis.page 45 Th e r e gi on al anal ys es for th e i nterim em issions tests in a m u lti-st ate area would co ver ei

th er th e po rtion of a s t ate’ s 8- ho ur area n ot co vere d b y its 1- ho ur budget s, ora s t ate’ s en tire 8- ho ur area. 12

12 Th e J uly 1, 2004, final rule al so pr ovid es a t hir d i nterim em issions test option forcertain S cenar io 3 m ulti-st ate areas : th e r e gi on al em issions anal ysis could co ver th e en tire multi-st at e area. Pl ease co ns ul t EPA before ch oosing t his option to di sc us s its impli cat ions.