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# OAR Box 1830 Prepped byOllie Stewart



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Number: 

# 201 ) IV-C-16

8 Docket Number: 

# A-87-1 1

Printed 11/13/20087:21:02 AM Sheet 201 of 232

## A-S7-! /

^ t osr 4 > P Ar i UNITE D STATE S ENVIRONMENTA LPROTECTIO N AGENC Y

' T W /

AN N ARBOR . MICHIGA N 4810 5

% «*.«• * OFFIC E O F AI R AN D RADIATIO N 

### JU N1 6 

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Mr . Stuar t Drak e Kirkland an

d Elli s 65 5 Fifteent hSt. , N W Washington , DC 2000 5

Dea r Mr . Drake : Inrespons e t o your conversatio nwit hJan e Roeme r o f our Offic e o f Genera l Counsel , enclose d i s a copyo f th e memo o f Decembe r 2 2 1988 , fromJea nSchwendema nt o the Record , subject : "Onboard an d Evaporativ e Contro l SystemCos t Estimate s fo r the Supplementa l Notic e o f Propose d Rulemaking" . Sincerely , 

# /; /Y 7 

## ^^ John/P . Anderson , Senio r Projec t Manage r Standard s Developmen t an d Suppor t Branc h Enclosur e

cc : Jan e Roemer , OG C (LE-132G ) (w/ o enclosure ) Docke t A-87-1 1 , Docke t A-85-2 1 1086 wP. 3

^ 0Sr "r i UNITE D STATE S ENVIRONMENTA LPROTECTIO N AGENC Y \+)k^j

AN N ARBOR . MICHIGA N 4810 5 -Up*** ' OFFIC E O F HE C 2 2'"? ^

AI R AN D RADIATIO N

MEMORANDU M

SUBJECT : Onboar d and Evaporativ e Contro l Syste mCos t

Estimate s fo r th e Supplementa l Notic e o f Propose d Rulemakin g
FROM : -Jea

n Schwendeman , Mechanica l Enginee r *-/<- • •'- ' •->.'.,.• _ ; w-;. . •...<. . Standard s Developmen t and Suppor t Branc h ^O : Th e Recor d THRU : Glen n.7 . Passavant , Senio r Projec t Manage r 10'-Zi^.**'

Standard s Developmen t and Suppor t 3ranc h Richar d A . Rykowski , Senio r Projec t Manag e Standard s Developmen t an d Suppor t Branc h Introductio n Thi s memorandu mdescribe s i ndetai l th e ne wcos t estimate s fo r th e improve d evaporativ e syste mand

- th e onboar d refuelin g vapo r recover ysystem , a s discusse d i nth e Supplementa l Notic e o f Propose d Rulemaking . Th e analysi s no r th e improve d evaporativ e syste mwa s performe d fo r bot h9. 0 and 11. 5 os i RV P certificatio n fuel . A s i s discusse d furthe r below , th e onboar d analysi s assume s a 9. 0 ps i RV P certificatio n fuel . Th e estimate s wil l b e show na s incrementa l cost s fo r eac h additiona l leve l o f control . Th e cost s fo r "improved " evaporativ e system s ar e incrementa l t o thos e fo r "excess " evaporativ e system s and th e revise d cost s fo r onboar d system s ar e incrementa l t o bot ho f these . ?o c thi s memorandum , .eac ho f th e differen t contro l level s ar a define d a s follows :P. 4



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- "excess " evaporativ e system- th e vehicle-base d system designe d for contro l o f evaporativ e emission s a s outline d i nth e propose d volatility/evaporativ e rulemaking (5 2 F R 31274) . Th e estimate d cos t fo r thi s systemwa s calculate d a s anincrementa l cos t t o th e curren t evaporativ e system . Th e detaile d cos t analysi s o f thi s systemi s found i nth e July , 198 7 Volatility , Draf t RegulatoryImpac t Analysis.[l ] "improved " evaporativ e system- the vehicle-base d system designe d for contro l o f evaporativ e emission s a s outline d i nth e supplementa l notic e o f propose d rulemaking . Thi s system woul d b e designe d t o contro l "running losses " and othe r evaporativ e emission s no t controlle d byeithe r th e curren t or exces s evaporativ e systems . Th e estimate d cos t for thi s systemwa s calculate d incrementa l t o th e cos t o f th e exces s evaporativ e system . "original " onboar d system- th e vehicle-base d syste m designe d t o contro l refuelin g emission s usin g hardwar e simila r t o tha t describe d i nth e onboar d proposa l (5 2 F R 31162) . Th e estimate d cos t fo r thi s syste mwa s calculate d incrementa l t o th e cos t o f th e exces s evaporativ e system . Th e detaile d cos t analysi s o f thi s syste mi s found i nth e July , 198 7 "Evaluatio no f Ai r Pollutio nRegulator y Strategie s fo r Gasolin e Marketin g Industry- Respons e t o Publi c Comments".[2 ] "revised " onboar d syste m- th e vehicle-base d system designe d t o contro l refueling emission s usin g hardwar e simila r t o tha t describe d i nth e supplementa l notic e o f propose d rulemaking . Th e estimate d cos t fo r thi s system wa s calculate d a s a nincrementa l cos t t o improve d evaporativ e system s an d totall yreplace s th e origina l cos t estimat e fo r th e onboar d system . Th e origina l onboar d and th e exces s evaporativ e emissio n regulation s (commonl yreferre d t o a s th e Volatilit yproposal ) wer e bot hpublishe d i nth e Federa l Registe r o nAugus t 19 , 1987 . Th e onboar d proposa l wa s develope d t o mandat e recovery o f emission s fro

mvehicl e fue l tank s durin g refueling . Th e exces s evaporativ e proposa l wa s develope d t o matc hin-us e and certificatio ngasolin e RVP s and t o contro l evaporativ e emission s relate d t o insufficien t caniste r purg e in-use . Thi s woul d b e don e b

yrequiring th e tes t vehicl e t o star t th e drivin g cycl e (FTP ) wit ha saturate d evaporativ e canister . A t th e tim e o f th e origina l proposals , EP Afull yexpecte d tha t manufacturer s woul d us e integrate d rathe r tha nseparat e refuelin g and evaporativ e contro l systems . Integrate d system s woul d provid e a degre e o f contro l o f running losse s an d othe r evaporativ e emission s whic hsometime s occu r durin g in-us e operation , becaus e th e portio no f th e caniste r necessar yt o handl e a loa d o f refueling vapor s i s availabl e t o handl e thes e othe r type s o f emission s durin g muc ho f th e tim e betwee nP. 5



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- refuelings . However , man ymanufacturer s hav e indicate d t o EP A tha t unde r th e origina l tes t procedure s theywoul d us e separat e system s whic hmayno t provid e th e extr a degre e o f contro l o f evaporativ e and runnin g los s emission s whic hwoul d b e provide d byanintegrate d system . Sinc e th e origina l proposals , EPAha s learne d tha t thes e emission s contribut e a muc hlarge r percentag e t o th e VO C inventorytha nwa s previousl ythought . Th e magnitud e o f th e proble mmake s i t clea r tha t thes e emission s woul d nee d t o b e controlle d regardles s o f whethe r onboar d refueling control s ar e required . Becaus e o f thes e developments , th e supplementa l proposal s includ e revision s t o bot hth e onboar d an d evaporativ e proposal s t o ensur e tha t running losse s an d othe r evaporativ e emission s previousl yuncontrolle d unde r th e Federa l Tes t Procedur e woul d b e controlle d byeithe r integrate d o r separat e contro l system s i f onboar d refueling control s ar e required . Furthermore , thes e running los s and othe r evaporativ e emission s woul d hav e t o b e controlle d byth e vehicl e wit hanimprove d evaporativ e syste m unde r th e newl ypropose d evaporativ e regulation s eve n i f onboar d refueling control s ar e no t mandated . Th e revise d cos t estimate s detaile d i nthi s mem o incorporat e th e effect s o f th e change s t o th e onboar d and evaporativ e proposal s whic har e describe d above . Th e revise d cos t estimate s ar e als o base d upo na simplifie d onboar d system concep t develope d ove r th e pas t yea r along wit hsimplification s i nth e refuelin g tes t procedure . Thes e simplification s ar e describe d i nth e Supplementa l Notic e o f Propose d Rulemaking . Becaus e improve d evaporativ e system s coul d potentiall yb e require d independen t o f onboar d refueling control , th e cost s o f onboar d control s ar e calculate d a s incrementa l t o th e cost s o f improve d evaporativ e controls . Th e cost s o f bot ho f thes e system s ar e calculate d incrementall yt o th e exces s evaporativ e contro l systemdescribe d i nth e propose d volatility/evaporativ e rulemaking (5 2 F R31274) . Sinc e thi s analysi s i s par t o f a reproposal , th e methodologyand value s use d i nth e origina l proposa l wer e change d onl ywher e th e abov e development s mad e i t necessary . Summaryo f Estimate d Cost s Th e cos t estimate s wer e mad e fo r typica l vehicle s fromal l thre e gasolin e vehicl e classes : light-dut yvehicle s (LDVs) , light-dut ytruck s (LDTs) , and heavy-dut ygasolin e vehicle s (HDGVs) . Th e same 198 9 projecte d sale s wer e use d a s i n th e origina l onboar d proposal : 11. 2 millio nfo r LDVs , 3.7 1 millio n fo r LDT s an

d 0.38 4 millio nfo r HDGVs . Thes e resul t i na sale s weightin g o f 73. 2 percen t fo r LDVs , 24. 3 percen t fo r LDT s an d 2. 5 percen t fo r HDGVs . Asummaryo f th e estimate d cost s fo r th e exces s evaporativ e systems , improve d evaporativ e systems ,P. 6

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Tabl e I A Exces s Evaporativ e Syste mCost s (Incrementa l t o Curren t Evap ) 9 o ps i RV P Certificatio nFue l

Vehicl e LD V LD T HDG V Vehicl e

Cos t Increas e 1.4 5 1.8 5 3.3 5 weigh t

Penalt y 0.0 0 0.0 0 0.0 0 Fue l Ne t cos t

parwpr yCredit* * t o Owne r

N.A . N.A . N.A , Sale s weighte dNe t Cos t 1.4 5 1.8 5 3.3 5 1 . 6 0

Vehicl e LD V LD T HDG V Tabl e I B

Improve dEvaporativ e Syste mCost s (Incrementa l t o Exces s Evap) * 9. 0 ps i RV P Certificatio nFue l Vehicl e r.ns t Increas e 9.6 5 13.4 0 11.2 5 Weigh t

Penalt y 0.5 0 1.1 5 0.6 0 Fue l

RecoveryCredi t 12.3 0 20.6 5 38.7 5 Sale s Weighte dNe t Cos t N e t Cos t t o Owne r -2.1 5 -6.1 0 -26.9 0 -3.7 0

Cost s ar e i nRP E fo r 198 8 dollar s rounde dt o th e neares t nickel . Sale s weights : LD V 73.2% ; LD T 24.3% ; HDG V 2.5% . T h e tota l fue l recover ycredi t o f exces s evaporativ e system s woul d b e th e resul t o f an yvehicl e change s an d als o o f matchin g certificatio nan d in-us e fue l RVPs . I t i s difficul t t o determin e th e portio no f th e credi t du e solel yt o vehicl e changes , s o non e ar e use dhere .P. 8



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Tabl e I C Revise d Onboar d Contro l SystemCost s (Incrementa l t o Improve d Evap) * 9. 0 ps i RVP Certificatio n Fue l vehicl e Weigh t Fue l Ne t Cos t Vehicl e Cos t Increas e Penalt yRecoveryCredi t t o Owne r LD V 0.9 0 0.0 0 4.2 0 -3.3 0 LDT 1.5 0 0.0 0 6.6 5 -5.1 5 HDG V 5.2 0 0.0 0 12.6 0 -7.4 0 Sale s Weighte d Ne t Cos t -3.9 0

Tabl e I D Tota l Cost s fo r Onboar d an d Evaporativ e SystemChanges * 9. 0 ps i RVP Certificatio n Fue l Vehicl e weigh t Fue l Ne t Cos t Vehicl e Cos t Increas e Penalt yRecover yCredi t t o Owne r LD V 12.0 0 0.5 0 16.5 0 -4.0 0 LD T 16.7 5 1.1 5 27.3 0 _ -9.4 0 HDG V 19.8 0 0.6 0 51.3 5 -30.9 5 Sale s weighte d Ne t Cos t -6.0 0
Cost s ar e inRP E for 198 8 dollar s rounde d t o th e neares t nickel . Sale s Weights : LD V 73.2% ; LD T 24.3% ; HDG V 2.5% .P. 9



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- Four value s ar e show nfo r eac hleve l o f contro l an d eac h vehicl e class : vehicl e cos t increase , weigh t penalty , fue l recoverycredit , and ne t cos t t o th e consumer . Th e vehicl e cos t increas e reflect s th e additiona l "sticke r price " fo r a typica l vehicl e wit hth e indicate d additiona l leve l o f emissio n control . Th e weigh t penalt yreflect s th e sligh t increas e in . vehicl e weigh t du e t o th e additiona l emissio ncontrol s an d i s quantifie d i nterm s o f th e cos t o f th e additiona l fue l consume d byth e vehicl e ove r it s lifetime du e t o thi s additiona l weight . Th e fue l recoverycredi t i s th e saving s i nlifetime fue l cost s du e t o th e consumptio no f recovere d fue l vapor s by th e engine . Th e ne t cos t t o th e owne r i s th e summatio no f th e vehicl e cos t increas e an d th e weigh t penalt yles s th e fue l recoverycredit . Th e weighte d ne t cos t i s th e weighting o f th e ne t cost s o f LDVs , LDTs , and HDGV s b yth e fractio no f tota l sale s o f th e vehicl e class . Th e sam e sale s fraction s ar e use d her e a s thos e detaile d i nVolum e I I o f th e Refuelin g Control s Draf t RegulatoryImpac t Analysis.[3 ] Asummaryo f th e estimate d cost s o f exces s evaporativ e system s an

d improve d evaporativ e system s fo r 11. 5 RV P fue l i s showni nTable s 2 Aan d 2B , respectively . Asummatio ni s shown i nTabl e 2C . Onc e again , al l value s ar e RPE s i n198 8 dollars . Th e weigh t penaltie s an d fue l recoverycredit s wer e no t calculate d fo r th e revise d onboar d system s usin g 11. 5 RV P fuel . Thi s i s becaus e onl yth e vehicl e cost s o f exces s evaporativ e an

d improve d evaporativ e system s wer e neede d t o determin e th e cos t effectivenes s o f evaporativ e an d volatilit y controls . Tha t analysi s showe d tha t i t appeare d t o b e cos t effectiv e t o limi t in-us e fue l t o 9. 0 RVP . Becaus e o f tha t result , th e cost s o f onboar d system s wer e calculate d incrementall yt o improve d evaporativ e system s onl ya t 9. 0 RVP . Discussio no f Improve d Evaporativ e System s Existin g evaporativ e system s ar e onl ydesigne d t o handl e typica l diurna l and ho t soa k emission s generate d unde r averag e temperatur e condition s and a t averag e frequencie s o f occurrence . Th e improve d evaporativ e systemwoul d hav e th e capacit yt o handl e thes e type s o f evaporativ e emission s whe n the yar e generate d unde r mor e extrem e condition s suc ha s th e hig htemperature s typica l o f ozon e violatio nday s an d th e multipl e diurnal s whic hoccu r i f a vehicl e i s no t use d fo r severa l consecutiv e days . Th e improve d evaporativ e system s woul d als o hav e th e capacit yt o handl e running losses , whic har e cause d byhig hroad temperature s an d ho t fue l returne d fromth e engin e compartmen t whic hheat s an d sometime s eve nboil s th e fue l i nth e fue l tank . A t present , i nman yfue l system designs , a larg e amoun t o f thes e fue l tank vapor s leak int o th e atmosphere .

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- Tabl e 2 A Exces s Evaporativ e SystemCost s (Incrementa l t o Curren t Evap) * 11. 5 ps i RVP Certificatio n Fue l Vehicl e Vehicl e Cos t Increas e LD V 5.0 5 LDT 6.2 5 HDG V 9.3 5

Tabl e 2 B Improve d Evaporativ e System-Cost s (Incrementa l t o Exces s Evap) * 11. 5 ps i RVP Certificatio n Fue l Vehicl e Vehicl e Cos t Increas e LD V 26.7 5 LDT 37.9 0 HDG V 34.8 0

Tabl e 2 C Tota l Cost s fo r Evaporativ e SystemChanges ' 11. 5 ps i RVP Certificatio n Fue l Vehicl e LD V LD T HDG V Veh : Lcl e Cos t Increas e 3 1 4 4 4 4 8 0 1 5 1 5
Notes : 11. 5 ps i RVP certificatio n fuel . Cost s ar e i nRP E fo r 198 8 dollar s rounde d t o th e neares t nickel .P.1 1



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- Improve d evaporativ e system s ar e abl e t o captur e thes e additiona l emission s i f significantl ylarge r canister s ar e use d tha nthos e found o nexisting evaporativ e contro l systems . Th e siz e o f th e caniste r ha s a larg e effec t onsystemcost , a s wel l a s o nsystem

effectiveness . EPAha s bee nanalyzing th e relationshi p betwee nth e caniste r siz e an d th e operationa l characteristic s o f th e purg e systeman d throughthi s effor t ha s develope d a ne wcaniste r sizing model . Th e ne wmode l make s us e o f instantaneou s drivin g schedul e speed s an d acceleration s i n contras t t o averag e values . Wit hthi s procedure , interaction s betwee ndrivin g patterns , purg e contro l an d flowrate , fue l tan k vapo r generatio nan d charcoa l adsorptio ncharacteristic s ar e mor e realisticall ysimulated . Change s i nth e caniste r load an d th e quantit yo f hydrocarbon s purge d fromth e caniste r ar e predicte d a s a functio no f time . Th e mode l i s detaile d i nth e P T Mode l Descriptio nand User s Guide.[4 ] EPAestimate s tha t canister s o nLDV s wil l increas e from 1. 3 liter s (L ) fo r exces s evaporativ e system s t o 2. 7 L wit h9. 0 RVP certificatio n fue l for improve d evaporativ e systems . Th e 1. 3 L siz e o f th e exces s evaporativ e caniste r i s th e averag e o f curren t LD

V evaporativ e canister s a s wa s determine d i na surve y detaile d i nEPA' s Volatilit yDraf t Regulator yImpac t Analysis . [1 ] Th e 2. 7 L averag e siz e fo r LD V improve d evaporativ e system s i s base d upo nth e ne wmodel . Similarly , i f 11. 5 RVP certificatio n fue l i s used , canister s o nLDV s ma y increas e i nsiz e from2. 1 L t o 9. 3 L . I naddition , fue l coolin g strategie s ma yb e require d t o minimiz e boiling . Th e caniste r size s for th e variou s system s o nLDT s an d HDGV s wer e derive d following th e same analysi s a s th e LDVs . EPAexpect s tha t mos t LD V an d LDT manufacturer s wil l instal l th e improve d evaporativ e caniste r i nth e rea r o f th e vehicle . Thi s are a ofte nha s mor e spac e tha ntha t whic hi s availabl e i nth e engin e compartment . Sinc e nearl yal l LDV s an d LDT s ar e fue l injecte d ther e i s n o nee d t o plac e th e caniste r i nth e engin e compartmen t t o captur e carbureto r bowl-ven t vapors . HDG

V manufacturer s wil l probabl ycontinu e t o plac e thei r canister s i nth e existing location s o nthei r vehicle s becaus e o f th e greate r amoun t o f packaging spac e available . Th e numbe r an

d siz e (diamete r an d length ) o f vapo r line s going t o an

d fromth e caniste r ca nals o affec t wher e canister s ar e placed . Canister s locate d i nth e rea r o f th e vehicl e ar e close r t o th e fue l tank , whic hwil l minimiz e th e siz e o f th e vapo r line betwee nth e fue l tan k an d canister . wit hth e dominanc e o f fuel-injecte d vehicles , th e vapo r lin e betwee nth e caniste r an

d carbureto r bowl(s ) i s no longe r neede d an d therefor e i s n o longe r a consideratio nfo r caniste r placement . Canister s wil l stil l nee d a purg e line , bu t thi s lin e woul d b e approximatel yth e same siz e and follo wth e sam e routing from th e rear-mounte d caniste r t o th e engin e compartmen t a s th e existing vapo r lin e betwee nth e fue l tank an d th e front-mounte dP.1 2

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- canister . Th e feasibilit yo f rear-mounte d canister s i s supporte d b

yGenera l Motor s whic hi s alread yplacing evaporativ e canister s i ntha t locatio no nthei r W-bod yca r line . Manufacturer s wil l hav e t o improve th e purg e systemi n orde r t o handl e the increase d caniste r vapo r load . EP Aexpect s tha t manufacturer s wil l increas e th e purg e rat e an d wil l contro l th e purg e wit hfrequenc ymodulate d solenoi d valves . EPAexpecte d thes e valve s t o b e use d o nal l vehicle s t o contro l exces s evaporativ e emission s i f certificatio n fue l wen t t o 11. 5 RVP. ' However , du e t o th e muc hgreate r quantit yo f vapor s whic h wil l b e handle d b yimprove d evaporativ e systems , EP Ano w expect s tha t frequenc ymodulate d solenoi d valve s wil l b e use d onal l vehicle s regardles s o f whethe r th e certificatio n fue l i s 9. 0 o r 11. 5 RVP . Thes e change s i nth e evaporativ e systemincreas e th e vehicl e cost s t o contro l evaporativ e emissions . However , thes e change s als o resul t i na reduce d incrementa l vehicl e cos t allocate d t o th e onboar d contro l o f refueling emissions . Discussio no f Revise d Onboar d System s EPA' s concep t o f th e hardwar e require d fo r a nonboar d system ha s change d betwee nth e time o f th e origina l proposa l an d th e supplementa l proposal . Base d o nadditiona l analysi s an d system

testing , EP Alearne d tha t th e propose d onboar d system coul d b e simplified . Thi s concep t chang e resulte d i na significan t reductio ni nth e estimate d systemcost . Th e majo r change s i nth e revise d onboar d contro l systemconcep t sinc e th e origina l proposa l ar e liste d below . 1 . Canister s wil l b e locate d i nth e rear o f th e vehicle s instead o f i nth e engin e compartment s (for LDV s an d LDT s only) . Thi s wil l allo wa smalle r diamete r and shorte r vapo r lin e t o b e use d tha ntha t for a front-mounte d canister . Thi s locatio ni s consisten t wit hth e improve d evaporativ e systemdiscusse d above . Th e estimate s o f th e refueling contro l caniste r size s hav e change d sinc e th e origina l proposa l becaus e th e ne wmodellin g teclmique s use d t o siz e th e improve d evaporativ e canister s wer e als o applie d t o refueling canisters . .Another chang e i nth e analysi s sinc e th e origina l proposa l i s tha t EP Aassume d virtuall yal l vehicle s wil l b e fuel-injecte d b yth e tim e tha t thes e proposal s ar e implemented . O nfue l injecte d vehicles , vapor s ar e onl ycollecte d fro mth e fue l tank rathe r tha nfro m bot hth e fue l tank an d th e carbureto r ven t bowl . Wit hth e fue l tank a s th e sol e sourc e for vapors , i t wa s assume d tha t al l vehicle s wil l us e integrate d system s (on e caniste r fo r bot h refueling an

d evaporativ e emission s control ) fo r cost , desig n an d safet yreasons .P.1 3



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- 2 . Vapor s wil l b e route d fro mth e top o f th e fue l tank througha vent/rollove r valve , rathe r tha nfromth e fillneck . Thi s chang e greatl ysimplifie s th e propose d onboar d system . Th e existing externa l ven t lin e betwee nth e fue l tan k an d fillnec k opening canthe nb e eliminated . I naddition , th e fillnec k mounte d valv e describe d i nth e origina l proposa l i s n o longe r needed . However , th e vent/rollove r valv e use d for evaporativ e emission s woul d hav e t o b e modifie d t o accommodat e a 1 0 gpmfue l dispensing rat e an d woul d als o hav e t o incorporat e a fil l limiting function . 3 . Th e existing fillnec k wil l provid e a liqui d sea l withou t th e us e o f a J-tub e (onLDVs , LDTs , an d ligh t HDGVs) . EPAha s don e testing whic hsupport s thi s concept . Th e heavie r HDGVs , especiall ythos e wit hsaddle-tanks , wil l stil l nee d some hardwar e change s t o provid e a seal . 4 . Liquid/vapo r separator s wil l no t b e require d wit h th e adven t o f onboar d systems . Thi s remain s t o b e a manufacturer s desig noption , a s i s th e cas e o hcurren t vehicles . 5 . .Anti-spitback valve s wil l b e use d t o improv e refueling safety . Some manufacturer s ar e alread ystarting t o instal l thes e device s i nthei r produc t lines . A s previousl ystated , thes e change s i napproac han d system concep t resulte d i na reductio ni nth e estimate d cos t fo r onboar d systems . Adetaile d discussio no f th e revise d cos t estimat e for bot honboar d an d improve d evaporativ e system s no w follows . Detaile d Discussio no f th e Cos t Analyse s Th e cos t analyse s hav e bee nupdate d i nth e area s whic h wer e affecte d b

yth e change s mad e i nth e propose d evaporativ e contro l regulation , change s i nth e onboar d contro l system concept , an

d i nth e caniste r sizing model . Value s no t affecte d bythes e change s wer e adjuste d fo r inflation , bu t ar e otherwis e identica l t o th e value s use d i nth e origina l proposals . Th e mark-up facto r representin g manufacture r an d deale r profi t i s stil l 1.2 6 fo r LDV s an d LDTs , an

d 1.2 7 fo r HDGVs . Th e adjustmen t fo r inflatio nwa s base d o nth e rati o o f Consume r Pric e Indexe s (CPI ) fo r ne wcar s a s recorde d i n MVM A Moto r Vehicl e Fact s & Figure s '86 . A t th e tim e o f th e analysis , CPI s wer e onl yavailabl e through1986 . Usin g th e 198 6 inde xo f 224. 4 an d th e 198 4 inde xo f 208.5 , th e inflatio n fo r a ne wca r betwee n198 4 an d 198 6 wa s found t o b e 7. 6 percen t (224. 4 divide d by208.5) . Thi s same rat e wa s als o use d t o estimat e th e inflatio nbetwee n198 6 and 1988 . Th e tota l inflatio nbetwee n198 4 an d 198 8 i s therefor e 15. 8 percent .P.1 4

-12

- Th e improve d evaporativ e an d onboar d systemcos t analysi s i s discusse d i ndetai l according t o th e following thre e categories : hardwar e costs , developmen t costs , an d recovery credits . Withi neac ho f thes e categories , a separat e discussio nwil l b e mad e fo r th e improve d evaporativ e cost s incrementa l t o th e exces s evaporativ e cost s an d th e revise d onboard cost s incrementa l t o th e improve d evaporativ e costs . Th e cost s describe d belo war e fo r al l gasolin e LDVs , LDTs , an d HDGVs . Note s ar e mad e wher e th e value s onl yrefe r t o a subse t o f thi s group . A . Hardwar e Cost s 1 . Introductio n Th e hardwar e component s discusse d fo r th e improve d evaporativ e systemare : canister , vapo r lines , purg e valve , vent/rollove r valve , an d fue l cooling . N o additiona l cos t wa s allocate d fo r EC Umodifications . I t wa s assume d tha t th e ne t cos t allocate d fo r reprogramming th e EC Ui nth e origina l volatilit yproposa l (i.e. , exces s evaporativ e control ) wa s sufficien t for th e tota l change s i nth e system . Tabl e 3 summarize s the cost s fo r th e improve d evaporativ e system s incrementa l t o exces s evaporativ e system s fo r LDVs , LDT s (singl e and dua l fue l tank) , an d HDGV s (singl e and dua l fue l tank) . Value s ar e show nfo r bot h9. 0 an d 11. 5 ps i RV

P certificatio n fuel . Th e cost s ar e i nRP E and hav e bee nrounde d t o th e neares t nickel . Th e hardwar e component s discusse d fo r th e revise d onboar d system ar e the : canister , vapo r lines , vent/rollove r valve , anti-spitbac k valve , an d sea l assembl y(HDGVs) . Th e revise d onboard contro l systemcost s ar e show ni nTabl e 4 an d ar e incrementa l t o thos e incurre d fo r improve d evaporativ e system s (Tabl e 3) . Th e caniste r cost s ar e fo r canister s designe d fo r 9. 0 ps i RV P certificatio n fuel . Th e cost s ar e i nretai l pric e equivalent s (RPE) , whic hinclude s th e markup s fo r manufacture r an d deale r profits . Al l value s hav e bee nrounde d t o th e neares t nickel . Th e origina l onboar d an d volatilit yproposal s use d tw o differen t approache s fo r analyzing th e hardwar e require d fo r HDGVs . Th e volatilit yproposa l groupe d al l HDGV s together . Th e onboar d analysi s represente d HDGV s a s Clas s li ban d Clas s V I vehicles , wher e Clas s li bvehicle s represente d 7 5 percen t o f th e HDG V flee t an

d Clas s V I vehicle s represente d 2 5 percen t o f th e fleet . Th e li ban d V I vehicle s wer e furthe r distinguishe d a s having eithe r singl e o r dua l fue l tanks . Eight ypercen t o f th e Clas s li bvehicle s hav e singl e fue l tanks , whil e 2 0 percen t hav e dua l tanks . Eighty-fiv e percen t o f th e Clas s V I vehicle s hav e singl e fue l tank s compare d t o 1 5 percen t wit hdua l tanks .Tabl e 3 Improve d Evaporativ e Syste mHardwar e Cost (i nRPE , 198 8 $) »

Item

Caniste r Vehicle/Certificatio nFue l

$3.8 0 Vapo r Line s 0.2 0 Purg e Valv e 1.0 5 Vent/Rollove r Valv e 3.8 0 Fue l Coolin g Syste m0.0 0 EC UMods* * 0.0 0 Tota l > V 11.5RV P $1516 5 0.2 0 0.0 0 3.8 0 6.3 0 0.0 0 LDT- S

9.0RV P $5.5 0 0.2 0 1.0 5 3.8 0 0.0 0 0.0 0 11.5RV

P $21.6 0 0.2 0 0.0 0 3.8 0 6.3 0 0.0 0 LDT-D

9.0RV P $11.0 0 0.4 0 1.0 5 7.5 5 0.0 0 0.0 0 11.5RVP

$43.1 0 0.4 0 0.0 0 7.5 5 6.3 0 0.0 0 HDGV- S

9.0RV P $2.5 0 1.1 0 1.0 5 3.8 0 0.0 0 0.0 0 11.5RV

P $17.3 5 1.1 0 0.0 0 3.8 0 6.3 5 0.0 0 $8.8 5 $25.9 5 $10.5 5 $31.9 0 $20.0 0 $57.3 5 $8.4 5 $28.6 0 HDGV- D 9.0RV P $7.0 0 2.1 5 1.0 5 7.6 0 0.0 0 0.0 0 11.5RV

P $39.4 0 2.1 5 0.0 0 7.6 0 6.3 5 0.0 0 $17.8 0 $55.5 0

* Incrementa l t o Exces s Evaporativ e System . Cos t previousl yallocate d t o Exces s Evaporativ e System .

* ••14

-

Componen t Remov e Ext ' 1 Ven t Lin e Vent/Rollove r Valv e Anti-Soitbac k Valve* * Vapo r Lin e Sea l Assembl y Carbo nCanister** * Tota l LDV -1.6 0 0.6 5 0.3 5 0.2 0 0.0 0 0.2 5 -0.1 5 LDT- S

-1.6 0 0.6 5 0.3 5 0.2 0 0.0 0 0.4 5 0.0 5 LDT- D -3.2 0 1.3 0 0.7 0 0.4 0 0.0 0 0.9 0 0.1 0 Ilb- S

-1.9 0 0.6 5 0.3 5 1.2 0 0.0 0 0.9 0 1.2 0 Ilb- D

- 3 .3 0 1.3 0 0.7 0 2.4 0 0.0 0 1.7 5 2.3 5 71- S

0.0 0 0.6 5 0 . 3 5 2 . 3 0 4.2 0 1.4 0 3.9 0 71- D

0.0 0 1.3 0 0.7 0 4.6 0 3.4 0 3.5 0 18.5 0

* Incrementa l t o Improve d Evaporativ e System . * * Some vehicle s alread yhave thi s hardware . Conservativ e estimate . ** * Caniste r size d Eor 9. 0 ps i RV PP.1 7

-15

- Th e analysi s for th e supplementa l proposa l use d th e Clas s li ban d Clas s V I HDG

V breakdownwher e i t wa s possible . However , t o calculat e incrementa l cost s for improve d evaporativ e systems , th e Clas s li ban d Clas s V I value s ha d t o b e weighte d int o single-tank HDGV s an d dual-tank HDGVs . Thi s weighting wa s base d o nth e ratio s use d i nth e origina l onboar d analysis . Sinc e Clas s li ban d Clas s V I represen t 7 5 an d 2 5 percen t o f th e HDG V fleet , weightin g th e previousl ystate d singl e an

d dua l tan

k percentage s b

yclas s implie s tha t 8 1 percen t o f HDGV s ar e singl e tan k whil e 1 9 percen t ar e dua l tank . O f th e single-tank HDGVs , 7 4 percen t ar e Clas s li bwhil e 2 6 percen t ar e Clas s VI . O f th e dual-tank HDGVs , 7 9 percen t ar e li bwhil e 2 1 percen t ar e Clas s VI . 2 . Caniste r Cos t Th e analysi s o f th e improve d evaporativ e an d revise d onboar d projecte d system s utilize d th e ne wcaniste r sizing mode l an

d typica l fue l tank sizes . Th e purg e rat e use d wa s 2 0 cubi c fee t pe r LA- 4 fo r LDV s an d LDTs , an

d 1 8 cubi c fee t pe r chassi s cycl e for HDGVs . Th e fue l tank sizes , whic haffec t caniste r size , wer e th e same a s thos e use d i nth e origina l proposal . Th e mode l use d t o estimat e caniste r cos t a s a functio no f caniste r siz e i s th e same a s tha t use d i nth e origina l proposals . Charcoa l cos t wa s stil l estimate d t o b e $1.4 0 pe r pound . Thi s valu e wa s no t inflate d du e t o a curren t pric e rang e o f $1.0 0 t o $1.5 0 give nb ycharcoa l manufacturers . Th e cost s use d i nestimating th e caniste r shel l wer e increase d b y 15. 8 percen t t o accoun t fo r inflation . Tabl e 5 show s th e fue l tan k sizes , caniste r sizes , an d caniste r cost s for th e exces s evaporative , improve d evaporativ e an d revise d onboar d systems . Th e incrementa l cost s ar e als o shown . Al l o f th e value s i nTabl e 5 ar e fo r 9. 0 ps i RVP certificatio n fuel . Cost s fo r 11. 5 ps i RVP certificatio n fue l ar e i nTabl e 6 fo r th e exces s an d improve d evaporativ e systems . Fo r th e caniste r siz e estimate s fo r 11. 5 RVP certificatio n fue l i t wa s assume d tha t manufacturer s woul d develo p fue l cooling system s t o reduc e vapo r generatio ni n orde r t o avoi d using aneve nlarge r canister . Th e vapo r generatio nrat e i s ver ylarg e wit h11. 5 RVP fue l becaus e th e fue l tank temperature s reache d durin g th e revise d tes t procedur e approac hth e boiling poin t o f th e manylighte r hydrocarbo ncomponent s whic hmak e up 11. 5 RV P fuel , and th e percentag e o f lighte r hydrocarbo ncomponent s i s greate r a t 11. 5 RVP tha na t 9. 0 RVP .Vehicle *

LD V LDT- S LDT- D Ilb- S Ilb- D VI- S VI- D HDGV- S HDGV- D Tw

o Tw o Tw o Fue l tan k Size(Gal ) 12. 2 16. 3 a t 16. 3 2 0 a t 2 0 3 0 a t 4 0 — — Revise dC

Caniste r Size(L ) 2. 8 4. 1 4. 1 e a 4. 7 4. 7 e a 7. 7 11. 0 e a — — Caniste r Cost s inboard Syste m

Tota l Cost**,** * 7.1 4 9.4 7 18.9 4 10.5 1 21.0 1 15.4 8 41.1 6 — — 

### (? ) Tabl e ! 5 (198 8 $) , 9. 0 ps i RV P Improve dEvaporativ e Sy s -Caniste r Size(L ) 2. 7 3. 9 3. 9 4. 3 4. 3 7. 0 10. 1 — Tota l

Cost**,***($ ) 6.9 5 9.1 2 18.2 4 9.8 2 19.6 4 14.3 6 38.4 2 11.0 0 23.5 8 Exces s Evaporativ e Syste m Caniste r Tota l Size(L ) Cost**($ ) 1. 3 3.9 2 1. 7 4.7 5 1. 7 9.5 0

4. 0 4. 0 9.0 5

18.0 9

Vehicle * LD V LDT- S LDT-D Ilb- S Ilb- D VI- S VI- D HDGV- S HDGV- D Incrementa lCos t($) , OnJx>ar d> Improve d Incrementa lCos t($) , Improve d> Exces s Vendo r 0.1 9 0.3 5 0.7 0 0.6 9 1.3 7 1.1 2 2.7 4 RPE*** *

0.2 3 0.4 4 0.8 8 0.8 7 1.7 4 1.4 2 3.4 8 Vendo r 3.0 3 4.3 7 8.7 4 — — — — RPE*** *

3.8 2 5.5 1 11.0 2 — — — — 1.9 5 5.4 9 2.4 8

6.9 7 o I

tanks , thi s cos t include s bot h * "S " = Singl e fue l tank . "D " = Dua l fue l tanks . * * Tota l caniste r cos t fo r vehicle . Fo r vehicle s wit hdua l canister s (on e caniste r pe r fue l tank) . ** * Th e caniste r cost s fo r revise donboar dan dimprove devaporativ e system s includ e a n additiona l cos t fo r dus t cap s ($0.2 5 pe r caniste r fo r LDVs , LDT s an dClas s li bHDGVs , $0.3 0 fo r Clas s V I HDGV s a t th e vendo r level. ) *** * RP E = Retai l Pric e Equivalen t (26 % marku pfo r LDV s an dLDTs , 27 % marku pfo r HDGVs) .

lo oTabl e 6

Vehicle * LD V LDT- S LDT- D Ilb- S Ilb- D VI- S VI- D HDGV- S HDGV- D Fue l tan k Size(Gal ) 12. 2 16. 3 Two a t 16. 3 2 0 Two a t 2 0 3 0 Two a t 4 0 Caniste r Cost s (198 8 $) , 11. 5 ps i RV P Improved Evaporativ

e Syste mExces s Evaporative Syste mIncrementa l Cos t ($ ) Caniste r Size(L ) 9. 3 13. 2 13. 2 13. 2 13. 2 21. 0 29. 4 Tota l

Cost**,***($ ) 17.9 4 23.8 2 47.6 4 23.8 2 47.6 4 35.0 6 93.1 5 26.7 4 57.2 0 Caniste r

Size(L ) 2. 1 2. 7 2. 7

6. 4 6. 4 Tota l

Cost**($ ) 5.5 1 6.7 1 13.4 1

13.0 9 26.1 7 Improved

Vendo r 12.4 3 17.1 1 34.2 3

13.6 5 31.0 3 > Exces s

RPE*** * 15.6 6 21.5 6 43.1 3

17.3 4 39.4 1

* * * "S " = Singl e fue l tank . "D " = Dua l fue l tanks . Tota l caniste r cos t fo r vehicle . Fo r vehicle s wit hdua l tanks , thi s cos t include s bot h canister s (on

e caniste r pe r fue l tank) . ** * The caniste r cost s for revised onboard an d improved evaporative systems include an additiona l cos t fo r dus t cap s ($0.2 5 pe r caniste r fo r LDVs , LDT s an d Clas s libHDGVs , $0.3 0 fo r Clas s V I .HDGV

s a t the vendo r level. ) *** * RP E = Retai l Pric e Equivalen t (26 % marku p for LDVs an

d LDTs , 27 % marku

p for HDGVs) .

* • C OP.2 0

•18

- Dus t cap s wer e adde d t o LD V an d LD T canister s becaus e i t i s assume d tha t the ywoul d b e locate d i nth e rea r o f th e vehicle , making the mmor e pron e t o dir t fromth e road . Th e cos t o f thes e dus t cap s wa s estimate d t o b e $0.2 5 pe r caniste r a t the vendo r level . AlthoughHDG V canister s ar e assume d t o remai ni nthei r presen t locatio ni nth e engin e compartment , dus t cap s wer e adde d i norde r t o mak e a conservativ e cos t estimate . Thes e dus t cap s wer e estimate d t o cos t $0.3 0 pe r caniste r a t the vendo r level . 3 . Vapo r Line s Th e vapo r line s ar e use d t o rout e fue l vapor s betwee nth e fue l tank , canister , engine , etc . I nth e origina l onboard proposal , EPAassume d tha t al l vapo r line s wer e mad e o f epichlorohydri n(ECO ) rubbe r tubing . Wit hfurthe r investigation , EPAha s learne d tha t manufacturer s frequentl y us e welde d stee l tubing wit hrubbe r connectin g pieces . EPAha s therefor e modifie d it s cos t analysi s t o includ e stee l tubing . Avendo r provide d cos t pe r foo t price s fo r large-scal e sale s o f tern e coated , weldin g stee l tubing , havin g a wal l thicknes s o f 0.02 8 inches . Value s wer e give nt o a tent ho f a cen t accurac yfo r 5/16-inc han d 3/8-inc hO.D . tubing . Price s fo r othe r tub e size s wer e obtaine d byextrapolatin g fromthes e give nprice s an

d the nrounding t o th e neares t penny . Th e result s ar e give nbelow :

Stee l Tubing Vendo r Cos t (198 8 $ ) 5/16 " I.D . = $0.10/ft . 3/8 " I.D . = $0.11/ft . 1/2 " I.D . = $0.14/ft . Th e cost s fo r rubbe r tubing wer e obtaine d fromth e origina l onboar d proposa l wit hanadjustmen t mad e fo r inflation . Th e cost s fo r 1/ 2 an d 5/16-inc htubin g wer e obtaine d from

a graphica l curv e fi t o f th e 1/4-inch , 3/8-inch , an d 5/8-inc hvalues . Th e result s fo r th e rubbe r tubin g cos t ar e give nbelow :

Rubbe r Tubing Vendo r Cos t (198 8 $ )

I . 1/4 " I.D .

5/16 " I.D . 3/8 " I.D . 1/2 " I.D . 5/8 " I.D . Externa l Ven t Lin e = $0.31/ft . = $0.34/ft . = $0.37/ft . = $0.46/ft . = $0.58/ft .

Th e externa l ven t lin e i s presentl yuse d o nvehicle s t o allowvapor s t o escap e fromth e fue l tank during refueling . Th e us e o f externa l ven t line s allow s fo r th e fillpip e t o b e smalle r i ndiamete r sinc e i t onl yneed s t o handl e fue l flowP.2 1

-19

- instead o f fue l an d vapo r flow . Wit hth e contro l system describe d i nth e supplementa l onboar d proposal , refueling vapor s wil l b e route d ou t o f th e to p o f th e fue l tank t o th e onboar d refueling canister . Becaus e o f thi s ne wrouting , th e externa l ven t line wil l n o longe r b e needed . Thi s line ca n therefor e b e remove d fro mfutur e vehicle s wit ha corresponding cos t savings . Th e externa l ven t line fo r LDV s an d LDT s wa s assume d t o hav e a 1/2-inchI.D. , b e thre e fee t long , an d b e compose d o f a one-foo t long stee l midsectio nan d two one-foo t lon g rubbe r connector s o nbot hends . Clearl yther e ar e variation s o nthes e size s an

d thi s desig nwhic hcoul d lea d t o some smal l cos t variations . Th e cos t o f th e externa l ven t lin e fo r LDVs an d LDT s wa s calculate d a s follows :

2 ' Rubbe r @ $0.46/f t = $0.9 2 1 ' Stee l @ $0.l4/f t = $0.1 4 4 Clamp s 0 $0.0 5 eac h= $0.2 0 Tota l $1.2 6 Markup (b

y1.26 ) $1.5 9 + $1.6 0 Fo r clas s li bHDGVs , a 1/2-inchI.D. , three-foo t rubbe r lin e wa s assumed. . Th e rubbe r lin e allow s fo r mor e flexibilit y fo r second-stag e manufacturers . Th e resulting cos t wa s calculate d a s follows :

3 ' Rubbe r <

3 $0.46/f t = $1.3 8 2 Clamp s @ $0.0 5 eac h= $0.1 0 Tota l $1.4 8 Markup (b

y1.27 ) $1.8 8 * $1.9 0 I t wa s assume d tha t th e fillneck s o nClas s V I HDGV s currentl yhav e a larg e enoughdiamete r t o allo wvapo r ventin g withou t usin g anexterna l ven t line . Therefor e ther e woul d b e n o cos t saving s associate d wit hthi s part . ii . Caniste r Relate d Vapo r Line s Th e caniste r require s tw o vapo r line s fo r prope r system operation : 1 ) th e vapo r ven t lin e fromth e fue l tank t o th e caniste r fo r vapo r loading , an d 2 ) th e purg e lin e fro mth e caniste r t o th e engin e fo r caniste r purging . Th e siz e (lengt h an d diameter ) o f th e vapo r line s i s dependen t o nth e caniste r location , th e vapo r flowrate , an d th e allowe d pressur e drop . Th e cos t depend s o nth e size , th e materia l use d an d th e constructio no f th e line . EP Aexpect s bot hth e onboar d an d improve d evaporativ e canister s t o b e locate d i nth e rea r o f th e vehicl e fo r LDV s an d LDTs . Therefore , ther e wil l b e a shor t vapo r ven t lin e betwee nth e fue l tank an d canister , bu t a long purg e line . I ncomparison , EPAexpecte d exces s evaporativ e-20

- canister s t o b e locate d i nth e fron t o f vehicles , a s the y typicall yar e for curren t systems . I nthi s case , th e vapo r ven t line betwee nth e fue l tank an d caniste r i s long , bu t th e purg e line i s relativel yshort . EPAsize d the vapo r line s for th e improve d evaporativ e an d th e revise d onboar d system s base d upo nth e expecte d flo wrate s an d allowe d pressur e drops . Fo r LDV s an d LDTs , th e purg e lin e o nth e improve d evaporativ e systemi s expecte d t o hav e th e same diameter , length , material s an d constructio na s th e fue l tank vapo r ven t lin e o f th e exces s evaporativ e system . Therefore , an ydifferenc e i nvapo r lin e cost s betwee nth e two system s i s du e t o th e differenc e betwee nth e improve d evaporativ e fue l tank vapo r ven t lin e an d th e exces s evaporativ e purg e line . The yar e expecte d t o hav e th e sam e length , material s an d constructio nbu t th e improve d evaporativ e fue l tan k vapo r ven t lin e mus t b e o f a large r diamete r tha nth e exces s evaporativ e purg e line . Fo r th e onboar d system , th e improve d evaporativ e purg e lin e i s expecte d t o b e o f adequat e siz e fo r purgin g th e onboar d canister . Therefore , th e onl ychang e i nvapo r lin e cost s betwee nth e onboar d an d th e improve d evaporativ e syste m result s fromth e nee d t o increas e th e diamete r o f th e improve d evaporativ e fue l tank vapo r ven t lin e t o b e adequat e fo r th e refueling vapo r flowrate . Fo r HDGVs , EPAassume d tha t ther e i s enoughspac e availabl e i nth e engin e compartmen t fo r improve d evaporativ e and/o r onboar d systemcanisters . I t wa s als o assume d tha t th e exces s evaporativ e systempurg e lin e i s adequatel ysize d fo r improve d evaporativ e and onboar d systems . However , ther e ar e incrementa l vapo r lin e cost s fo r improve d evaporativ e an d onboar d system s becaus e large r diamete r fue l tan k vapo r ven t line s ar e necessaryt o handl e th e greate r flo wrate s o f vapors . Th e cos t calculation s fo r vapo r line s fo r onboard , improve d evaporative , an d exces s evaporativ e system s ar e shown i nTabl e 7 fo r LDV s and LDTs , an d i nTabl e 8 fo r HDGVs . Fo r LDV s an

d LDTs , combination s o f variou s diamete r stee l an d rubbe r vapo r line s ar e assumed . Fo r HDGV s al l rubbe r tubing wa s used . Variation s i nthes e desig napproache s ar e possibl e whic h• woul d eithe r slightl yincreas e o r decreas e cost . Directionally , mor e us e o f stee l woul d decreas e cost s whil e mor e us e o f rubbe r woul d increas e costs .

### -21

- Tabl e 7

u a 

### n ^ r T.pve l Vaoo r Lin e Cost s - LDV s andLDT s

Exces s Eva p Purg e Lin e - 3f t < § 1/4 " 1 f t Rubber. @ $0.31/f t = * 0



### - 31 

### 7 f t Stee l a $0.08/f t = JL_i i Tota l Improve dEva p Fue i Tan k Vapo r Ven t Lin e - 3f t • 3/8 " 1 ft . Rubbe r 3 $0.37/f t = * Q 

### 'il 2 ft , Stee l 3 0.11/f t 0.2 2 = - - . $0.5 9 Tota l Onboar dFue l Tan k Vapo r Ven t Lin e - 3f t • • 1/2 " 1 ft . Rubbe r 3 $0.46/f t = 50.4 6 ?. ft . Stee l 3 0.14/f t = <Lil|

_ Tota l " ?0,7 4P.2 4

-22

- Tabl e 8 vendo c Leve l Va*- ^ r.in e Cost s - HDGV s Clas s Ub : Exces s Evap Fue l Tank Vapo r Ven t Lin e - 8 f t • 3/8 " 8 f t Rubbe r @ $0.37/f t = * 2

- y b Improve d Evap Fue l Tank Vapo r Ven t Lin e - 8 f t < 3 1/2 ' 8 f t Rubbe r d $0.46/f t ** * * J ' b 0 Onboar d Fue l Tank Vapo r Ven t Lin e - 8 f t 8 5/8 " 8 f t Rubbe r 8 $0.58/f t = * 4 ' b *

ClaSS Exces s Evap Fue l Tank Vapo r Ven t Lin e - 1 5 f t • 3/8 "

1 5 ft'Rubbe r 8 $0.37/f t = S 5

- " Improve d Evap Fue l Tank Vapo r Ven t Lin e -1 5 f t 8 1/2 " 1 5 f t Rubbe r 8 $0.46/f t = * 6

- 9 0 Onboar d Fue l Tank Vapo r Ven t Lin e - 1 5 f t 8 5/8 " 1 5 f t Rubbe r 3 $0.58/f t = $ 8.7UP.2 5

-23

- 4 . Vapo r Vent/Rollove r Valv e Modifie d vapo r vent/rollove r valve s ar e neede d fo r bot h th e improve d evaporativ e systeman d th e onboar d system . Man y vehicle s alread

yhav e some for

mo f vapo r vent/rollove r valve . However , t o mak e a conservativ e estimate , EP Adi d no t subtrac t th e cos t o f an

yexisting valv e fromth e cos t o f th e modifie d valv e whe nconsiderin g th e incrementa l cost s fo r improve d evaporativ e an

d revise d onboar d systems . Th e valv e require d fo r th e improve d evaporativ e system mus t allo wfue l tank vapor s t o b e vente d t o th e caniste r an d mus t als o clos e th e ventin g orific e durin g vehicl e rollover . Th e valv e ma

yals o hav e anorific e sealing devic e whic hi s bouyan t i ngasolin e ( a float ) tha t woul d protec t th e vapo r lin e fromsloshing fuel . Thi s floa t probabl ywil l no t nee d t o perform a fil l limiting functio nsinc e th e orific e o f th e valv e shoul d b e smal l enought o creat e sufficien t backpressur e t o caus e th e automati c dispensin g nozzl e t o shutoff . Thi s vapo r vent/rollove r valv e i s mounte d i nth e to p o f th e fue l tank . Th e onboar d systemvalv e wil l hav e a large r diamete r venting orific e i norde r t o handl e refueling vapo r flowrates . Wit hthi s large r diamete r orifice , th e bac k pressur e i nth e tank wil l probabl yno t b e sufficien t t o caus e automati c nozzl e shutoff . Th e valv e wil l nee d a fil l limiting floa t whic h close s of f th e ventin g orific e whe nth e tank i s ful l an d thereb ycreate s enoughbackpressur e i nth e tank t o caus e th e nozzl e t o shutoff . Th e floa t woul d als o provid e fue l sloshing protectio nfor th e valve . Becaus e th e mai norific e o f th e onboar d valv e i s close d whe nth e tank i s full , a smal l secondaryevaporativ e orific e i s necessaryi norde r t o allow tank ventin g a t tha t fil l level . Thi s secondaryorific e onl y need s t o b e abou t th e siz e o f some curren t evaporativ e orifice s whic hi s 0.0 5 inche s i ndiameter . .An yimprove d evaporativ e system valve s whic hhav e fill-limiting function s woul d als o nee d thi s secondaryorifice . EPAcontacte d a vendo r concernin g valv e desig nan d expecte d cost . Thi s vendo r presentl ysell s existing vent/rollove r valve s fo r jus t unde r thre e dollars . Th e existin g valv e configuratio n i s expecte d t o b e adequat e fo r th e improve d evaporativ e system(wit ha slightl ylarge r orific e - n o chang e i nmateria l cost) . Ther e i s n o cos t associate d wit h makin g th e valv e closur e devic e bouyan t (t o accomplis hfil l limiting and/o r t o provid e fue l sloshing protection) . Many evaporativ e systemvalve s currentl yhav e bouyan t shutof f devices . Thos e tha t don' t coul d switc hfromon e closur e mechanism , suc ha s bal l bearings , t o a float . Thi s woul d no t caus e anincreas e i ncos t an d i nfac t ma yb e les s expensive . EP Atherefor e allocate d a $3.0 0 manufacture r cos t t o th e improve d evaporativ e systemvalve . Th e onboar d systemvalv e ha s a slightl ylarge r diamete r orifice , a buoyan t floa t an d th e additiona l secondaryorifice . Ther e i s n o chang e i ncos t du e t o th e large r orific e o r th eP.2 6

-24

- bouyan t float . Howeve r th e cos t o f adding th e secondary orific e i s estimate d t o b e abou t $0.5 0 a t th e manufacturin g level . Th e vapo r ven t valv e for th e refueling systemi s thu s expecte d t o hav e a manufacturin g cos t o f $3.5 0 a t highvolum e production . Table s 3 an d 4 showthes e cost s i nRP E wit hth e appropriat e markup . 5 . Anti-Spitbac k Valv e Aliqui d sea l base d onboar d systemsuc ha s tha t discusse d i nthe supplementa l notic e mayrequir e a nanti-spitbac k valv e t o preven t fue l from"spitting " bac k ou t o f th e fillnec k a t automati c nozzl e shut-of f during vehicl e refueling . Som e manufacturer s ar e alread yincorporating thes e valve s i nsome o f thei r vehicl e models . Thi s wil l provid e a nadditiona l safet y featur e fo r onboar d system s ove r presen t systems . Avendo r quote d th e valv e cos t a t 2 5 cent s plu s tooling . Estimating th e tooling cos t a t 3 cent s an d adjusting fo r markup , EP Aestimate s tha t th e valve s wil l cos t 3 5 cent s each . Thes e cost s ar e shown i nTabl e 4 . 6 . Sea l Assembl y Onboar d system s requir e some typ e o f sea l t o preven t vapor s fro m

escapin g ou t th e fillnec k durin g vehicl e refueling . LDVs , LDTs , and Clas s li bHDGV s typicall y.have smal l diamete r fillneck s o f adequat e lengt ht o provid e a liqui d sea l durin g refueling . Therefore , n o cos t wa s allocate d fo r sea l hardware . However , Clas s V I HDGV s hav e severa l differen t fue l tank arrangements . Som e o f thes e fue l tank s hav e n o fillneck , some hav e shor t fillneck s and some hav e larg e diamete r fillnecks . Th e sealing mechanis mfo r thes e tank s ma y var ydependin g o ndesig nand locatio nconstraints . However , EP Abelieve s tha t manufacturer s wil l us e th e leas t expensiv e metho d possibl e t o provid e a nadequat e sea l an d i s therefor e using th e sam e valu e a s wa s develope d i nth e origina l proposa l (adjuste d fo r inflation) , withou t identifyin g a specifi c sea l design . EP Aexpect s tha t manydifferen t approache s coul d b e used , bu t non e tha t woul d b e mor e expensiv e tha nth e previou s estimat e fo r a sea l assembl yconsisting o f a mechanica l sea l an d a pressur e relie f device . 7 . Purg e Valv e I nth e origina l volatilit yproposal , fo r eac hvehicl e clas s EPAestimate d th e averag e cos t o f improve d purg e valve s whic hwoul d b e neede d t o handl e th e highe r purg e rat e necessary fo r exces s evaporativ e systems . EP Aassume d tha t th e improve d valv e woul d b e a frequenc ymodulate d solenoi d operate d b yth e ECU . Th e ful l cos t o f th e valv e fo r exces s evaporativ e system s incrementa l t o curren t evaportiv e system s wa s calculate d t o b e $0.9 6 i n198 6 dollar s a t th e manufacture r leve l ($1.3 0 i nRPE , 198 8 dollars) . EP Aexpecte d tha t onl ycarburete d vehicle s woul d nee d th e improve d valv e i f 9. 0 RVP fue l wa s used , bu t tha t al l vehicle s woul d nee d i t i f 11. 5 RV P fue l wa s used . Therefor e a t 9. 0 RV P onl yth e fractio no f th e ful l cos t o f th eP.2 7

-25

- valv e whic hwa s equivalen t t o th e fractio no f carburete d vehicle s predicte d t o b e i nth e flee t i n199 0 wa s calculate d a s anaverag e flee t cos t ($0.1 8 a t th e manufacture r leve l i n198 6 dollars , $0.2 5 RP E i n198 8 dollars) . Th e ful l cos t o f th e valv e wa s assume d fo r everyvehicl e a t 11. 5 RVP . EPAbelieve s tha t thi s same frequenc ymodulate d solenoi d valv e wil l b e adequat e fo r bot himprove d evaporativ e an d onboar d systems . However , i t i s expecte d tha t thes e system s wil l requir e the improve d valv e o nal l vehicle s a t 9. 0 RVP instead o f jus t o ncarburete d vehicles . Therefor e th e onl y purg e valv e cos t fo r improve d system s incrementa l t o exces s evaporativ e system s i s du e t o allocating th e ful l cos t o f th e valv e t o al l vehicle s a t 9. 0 RVP . Ther e i s n o incrementa l cos t a t 11. 5 RVP . Ther e i s als o n o cos t fo r onboar d system s incrementa l t o improve d evaporativ e system s fo r thi s component , sinc e th e sam e purg e valv e woul d b e used . 8 . Fue l Coolin g System Fo r improve d evaporativ e systems , i t appear s tha t i f 11. 5 RVP fue l i s use d some typ e o f cooling mechanis mmayb e require d fo r th e fue l retur nline i norde r t o reduc e th e amoun t o f vapor s bein g generate d i nth e fue l tank durin g vehicl e operation . Thi s migh t b e achieve d byaddin g coolin g fin s t o th e retur nlin e alon g wit hai r ductin g o r throughsom e othe r means . EP Aestimate d th e manufacturer' s cos t fo r thi s mechanis m

(o r some othe r simila r approach ) t o b e approximatel y fiv e dollars . B . Developmen t Cost s Developmen t cost s ar e al l cost s othe r tha ncomponen t hardwar e whic hfacto r int o th e fina l retai l pric e equivalen t (RPE ) o f th e vehicle . Thes e cost s ar e associate d wit hfue l tank modifications , vehicl e packaging , assembly , certification , facilit ymodification s an d system s engineering . Th e developmen t cost s use d i nthi s analysi s ar e al l base d upo n short-term

( 0 t o 5 years ) cost s t o th e manufacturer . Thes e cost s ar e recovere d byth e manufacture r afte r 5 year s (excep t fo r th e cos t o f facilit ymodifications , whic hi s recovere d afte r 1 0 years) . I f a long-termcos t analysi s wer e don e (greate r tha n5 years) , the nth e ne t cos t o f eac hsyste mwoul d decreas e an

d th e cos t effectivenes s woul d increase . Developmen t cost s wer e calculate d fo r bot hth e origina l volatilit y(exces s evaporativ e systems ) and th e origina l onboar d proposals . Th e following discussio nexplain s an y change s i nthes e cost s associate d wit hth e improve d evaporativ e an d revise d onboar d system s detaile d i nth e SNPRM . Improve d evaporativ e systemdevelopmen t cost s ar e showna s incrementa l t o exces s evaporativ e cost s an d onboar d cost s ar e showna s incrementa l t o improve d evaporativ e costs .P.2 8

-26

- 1 . Improve d Evaporativ e Svstem s I nth e origina l volatilit yproposal , th e non-hardwar e categoryinclude d cost s fo r certificatio n an d research , development , an

d testing (RD&T) . Tabl e 9 Asummarize s th e additiona l developmenta l (non-hardware ) cost s du e t o improve d evaporativ e systems . Al l value s ar e i nretai l pric e equivalent s and ar e rounde d of f t o th e neares t nickel . Eac ho f thes e value s ar e explaine d below . Packaging cost s aris e whe nhardwar e o r vehicl e modification s mus t b e mad e i norde r t o accommodat e ne w component s o r a nincreas e i nth e siz e o f ol d components . I n th e origina l volatilit yproposal , EP Aassume d tha t n o body modification s woul d nee d t o b e mad e t o accommodat e exces s evaporativ e system s an d tha t n o packagin g cost s woul d b e incurred . Som e packagin g cost s ma yaris e fo r improve d evaporativ e system s o nLDVs and LDT s du e to . th e increase d siz e o f th e canister , whic hEPAexpect s t o b e rear-mounted . EP A estimate s th e amortize d cos t (ove r 5 years ) t o manufacturer s t o b e $0.6 0 pe r vehicl e pe r canister . Ther e ar e n o spac e constraint s o nHDGV s whic hresul t i nanincrease d packagin g cost . However , manyClas s li bvehicle s ar e modifie d by secondarymanufacturer s wh o ma yincur anadde d cos t t o handl e th e ne wsystems . Therefore , anadde d cos t o f $0.6 5 a t th e manufacture r leve l wa s adde d fo r singl e tank Clas s lib s an d $1.3 5 for dua l tank Clas s libs . Althoug hsecondary manufacturer s d o no t modif ymanyClas s V I HDG V vehicl e fue l systems , packagin g cost s equa l t o thos e o nClas s lib s wer e adde d inorde r t o mak e a conservativ e estimate . Th e value s showni nTabl e 9 Areflec t th e appropriat e RP E markup value s fo r LDVs , LDT s an

d HDGVs . EPAdi d no t allocat e anadditiona l cos t t o improve d evaporativ e system s fo r RD&T . Cost s wer e previousl yallocate d t o exces s evaporativ e system s an d includ e th e cos t o f vehicl e acquisition , engineer s an d technician s salarie s and testing costs . Sinc e manufacturer s wil l b e developin g on e evaporativ e systempe r vehicl e famil y(rathe r tha na nimprove d syste mi n additio nt o a nexces s system ) n o additiona l cos t wa s needed .Ite

m Tabl e 9 A Improved Evaporative Syste mDevelopmen t Costs * (in RPE , 1988$ ) Vehicle/Certification Fue l LD V 9.0RV P 11.5RV

P LDT- S 9.0RV P 11.5RV

P LDT- D 9.0RV P 11.5RV

P HDGV- S 9.0RV P 11.5RV

P HDGV- D 9.0RV P 11.5RV

P Packagin

g 0.7 5 0.7 5 0.7 5 0.7 5 RD&T* * 0.0 0 0.0 0 0.0 0 0.0 0 Certification** * 0.0 5 0.0 5 0.0 5 0.0 5 1.5 0 0.0 0 0.0 5 1.5 0

0.0 0 0.0 5 0.8 5

0.0 0 0.0 5 0.8 5

0.0 0 0.0 5 1.7 0

0.0 0 0.0 5 1.7 0

0.0 0 0.0 5 Tota l $0.8 0 $0.8 0 $0.8 0 $0.8 0 $1.5 5 $1.5 5 $0.9 0 $0.9 0 $1.7 5 $1.7 5

* * * Cost s ar e incrementa l t o thos e expecte d fo r exces s evaporative control . Thes e cost s onl yappl yfo r 5 years . Cos t previousl yallocated t o Exces s Evaporative System . ** * Cos t t o ad

d tw o diurnal s an

d cap remova l t o FTP .-28

- Certificatio ncost s increas e i f ther e i s a nee d t o recertif ypreviou s mode l yea r vehicle s i norde r t o compl ywit h change d requirements . Certificatio n cost s als o increas e i f change s t o th e tes t procedur e mak e i t mor e resourc e intensive . Th e origina l volatilit yproposa l containe d a detaile d descriptio no f th e analysi s don e t o develo p th e cos t t o recertif yvehicle s equippe d wit hexces s evaporativ e contro l system s using 9. 0 RVP tes t fuel . Th e fractio no f vehicle s whic hmus t b e recertifie d i s th e same whethe r vehicle s ar e equippe d wit hexces s o r improve d evaporativ e systems . I t wa s estimate d tha t 9 0 percen t o f engin e familie s ar e carrie d ove r from th e previou s yea r an d s o recertificatio n cost s wer e applie d t o 9 0 percen t o f th e fleet . Sinc e th e origina l proposal , EPAha s learne d tha t whil e a 9 0 percen t carryove r ma y b e a goo d estimat e fo r durabilit yvehicles , th e fractio no f emissio ndat a vehicle s whic har e carrie d ove r i s close r t o 1 0 percent . Thi s make s EPA' s estimat e conservative , sinc e onl y1 0 percen t o f thos e vehicle s woul d actuall ynee d t o b e recertified . Refining th e estimat e a t thi s tim e woul d no t hav e a larg e impac t o nth e tota l cos t sinc e th e certificatio n cos t i s suc ha smal l fractio no f it . Thi s change , along wit hothe r improvement s i nth e estimates , wil l b e mad e a t th e tim e o f th e fina l rule . Th e cos t fo r certificatio n (or recertification ) tes t o f vehicle s wit himprove d evaporativ e system s i s greate r becaus e o f th e tw o diurnal s whic hhav e bee nadde d t o th e tes t procedur e fo r separat e systems . Th e two diurnal s resul t i na nadditiona l 0.3 5 Federa l Tes t ProgramEquivalent s (FTPEs ) plu s th e cos t o f fue l fo r two additiona l fill s t o th e 4 0 percen t level . Th e additiona l certificatio n cos t wa s calculate d base d upo nmanyo f th e same assumption s a s wer e use d i nth e origina l volatilit y proposal . On e significan t chang e i s tha t th e numbe r o f test s pe r HDG V famil ywa s reduce d from5 0 i nth e origina l volatilit y proposa l t o 10 . Thi s i s becaus e th e 5 0 test s i nth e origina l proposa l actuall yinclude d some test s fo r researc han d developmen t rathe r tha ncertification . Unlik e th e recertificatio n cos t calculatio no f th e exces s evaporativ e proposa l whic happlie d t o onl y9 0 percen t o f th e fleet , th e increas e i ncertificatio n cos t applie s t o th e entir e fleet

- Sinc e certificatio ni s don e approximatel yon e yea r befor e th e vehicle s ca nb e sold , cost s wer e increase d by1 0 percen t t o accoun t fo r th e itemvalu e o f money . Th e cos t calculation s fo r LDV s an d LDT s ar e show

ni nTabl e 9 B whil e th e calculation s fo r HDGV s ar e show ni nTabl e 9C . Th e additiona l cos t pe r vehicl e i nRP E rounde d t o th e neares t nicke l i s $0.0 5 fo r LDVs , LDTs , and HDGVs .P.3 1

-29

-

Tabl e 9 B Incrementa l Certificatio nCos t fo r Improve dEvaporativ e System s

(LDVs , LDTs ) LD V LD T Cos t o f FTP E 65 0 55 0 198 6 Dollar s (Fro m198 7 Volatilit yRIA ) Cos t o f FTP E 70 1 70 1 198 8 Dollar s Cos t o f 2 Refueling s a t 12. 2 ga l can k "* • S8.0 0 16. 3 ga l tan k ( 30 a o Single , 4 0 % fil l (S0.82/gallon ) 20 S Dual ) " * SL2.3 0 Additiona l Cos t pe r Tes t S253.3 0 257.6 5

= 0.35(FTPE ) * Fue l Cos t Durabilit yVehicl e Tests : 10 9 Vehicles/yea r 4 5 vehicles/yea r x1 3 tests/vehicl e x1 3 tests/vehicl e xS253.30/tes t xS257.65/tes t . . S35 9 K$15 1 K Additiona l Cos t fo r Emissio nDat a Vehicl e Tests : 30 7 Vehicles/yea r 13 3 vehicles/yea r x2 test/vehicl e x2 tests/vehicl e xS253.30/tes t x$257.65/tes t -$15 6 K~S 6 9 K Su mo f Durabilit yan d Emission s Dat a Cost : 551 5 K$22 0 K Ad d10 S fo r 1 yea r tim e Valu e o f mone yS56 7 KS24 2 K Amortiz e ove r 5 year s a t 10\ : 515 0 K$ 6 4 K (Amortizatio nfacto r = 0.2638 ) Sale s projection : 11. 2 millio n3.6 4 millio n Cost/Vehicle : 50.0 1 50.0 2 Cost/Vehicl e i nRP E Rounde dt o neares t nickel : 30.0 5 50.0 5-30

- Tabl e 9 C Incrementa l Certificatio n Cos t for Improve d Evaporativ e System(HDGVs' ,
Cos t o f FTPE : 198 6 Dollar s (Fro m198 7 Volatilit yRIA ) Cos t o f FTPE : 198 8 Dollar s Calculat e Averag e HDG V Fue l Tank Size :

Cos t o f 2 Refueling s a t 4O S fil l ($0.82/gal ) Additiona l Cos t pe r Tes t

= 0.3 5 (FTPE ) + Fue l Cos t Tota l Additiona l Cos t Ad d LO S fo r L yea r time : Valu e o f money S62 0

S66 7

lib : Single : 2 0 gal. Dual : 2 9 2 0 gal . lib : Weighted : (0.80).(2 0 gal ) • (0.20X4 0 gal ) = 2 4 gal . VI : Single : 3 0 gal . Dual : 2 5 4 0 gal . Weighted : (.85)(3 0 gal ) *

( .15X80

- gal ) = 37. 5 gal . Av g HDG V Tank Siz e = (0.75X2 4 gal ) • > (0.25X37. 5 gal ) = 27. 4 gal . $13.0 0

$25 1 ($251/test)(1 0 tests/family)(2 3 families ) = $5 8 K 56 4 K
Amorti- e ove r 5 year s a t 10 S 51 7 K (Amortizatio nfacto r = 0.2638 ) Sale s Projection : 386,00 0 vehicle s Incrementa l Cos t pe r Vehicle : $0.0 4 Cos t pe r vehicl e i nRP E Rounde d t o Neares t Nickel : SO.0 5P.3 3

-31

- 2 . Onboar d Svstem I nth e origina l onboar d proposal , th e non-hardwar e categoryinclude d cost s fo r fue l tank modifications , packaging , assembly , certification , facilit ymodifications , an d system s engineering . Thes e cost s mus t b e change d sinc e th e onboar d systemdesig nha s bee nrevise d an d sinc e onl yth e cos t incrementa l t o improve d evaporativ e systemdevelopmen t cost s ar e no wallocate d t o th e onboar d system . Tabl e 1 0 summarize s th e presen t developmen t costs . Al l value s ar e i nretai l pric e equivalent s and rounde d of f t o th e neares t nickel . Eac ho f thes e value s ar e explaine d below . Wit hth e developmen t o f a simple r onboar d systeman d wit h th e change s mad e i nth e evaporativ e proposal , th e cost s fo r fue l tan

k modification s an d fo r assembl yn o longe r apply . Th e fue l tan

k i s n o longe r being modifie d fo r a J-tube an d fil l limiter . Th e onboar d vapor/rollove r valv e mayrequir e a slightl ylarge r hol e i nth e fue l tank tha ntha t require d fo r th e evaporativ e vapor/rollove r valv e bu t thi s i s no t expecte d t o resul t i na cos t increase . Therefore , n o cos t wa s allocate d fo r fue l tank modifications . Th e origina l assembl ycos t considere d th e additiona l cos t t o instal l th e onboar d caniste r i nseparat e system s sinc e i t wa s though t tha t carburete d vehicle s migh t hav e separat e system s s o tha t th e evaporativ e caniste r coul d b e locate d nea r th e carbureto r whil e th e refueling caniste r woul d b e locate d nea r th e fue l tank . Thi s woul d minimiz e th e siz e an d lengt ho f th e vapo r an

d purg e lines . However , sinc e EP Ai s proposin g t o kee p certificatio n fue l a t 9. 0 ps i RVP , onboar d canister s woul d b e smalle r tha noriginall yestimated . I naddition , nearl yal l vehicle s wil l b e fuel-injecte d byth e time onboar d system s ar e required . Th e mos t importan t chang e sinc e th e origina l onboar d proposa l i s tha t improve d evaporativ e systemcanister s woul d b e nearl ya s larg e a s integrate d evaporativ e an d refueling canisters . Thi s make s integrate d system s muc hmor e attractiv e tha nseparat e system s sinc e les s tota l caniste r volum e an d fewe r connectiv e part s ar e necessary . Ther e is , therefore , n o additiona l assembl ycos t fo r installing onboar d system s incrementa l t o tha t fo r improve d evaporativ e systems . Mos t o f th e packagin g cos t o f anintegrate d onboar d caniste r i s alread yallocate d t o th e improve d evaporativ e system costs . However , some vehicl e model s mayrequir e additiona l bodymodification s fo r th e slightl ylarge r onboar d canister . EP Aestimate s thi s cos t t o hav e anamortize d valu e (ove r 5 years ) o f 1 0 cent s pe r vehicl e pe r caniste r (i nRPE) . N o cos t wa s allocate d fo r Clas s V I HDGV s du e t o thei r larg e siz e an d additiona l availabl e space . Cost s wer e conservativel y assigne d t o Clas s li bHDGVs , eve nthoughi nmanycase s adequat e spac e woul d b e available .P.3 4

-32 - Tabl e1 0 nnhnar dSvste mDevelooment^o^tslJir L _RPE^_1988_$ l

Ite m LD V Vehicl e

LDT- S LD M Ilbz iH M VI^ S VI ^

" * « nn« nn n$0.0 0$0.0 0$0.0 0 Tan k Mod s 5 00 0 $0 0$ 00 0» J0 0f ^ QO Q Assembl y0.0 00.0 0o.o o Q2 0QQ Q0i0 0 Packagin g OSLO' °'J ° Q.O O 0.0 00.0 00.0 0 Recertificatio n0.0 00-0 00.0 0o Q4 5 Q4 5 Q. 4 5 Facilit yMods* * 0.4 5 0-^ 5 u. « u 0 , 8 01.7 5 1-7 5 

# I'lWmvoj ajff

o ^1 0^^^„.2 o Tota l *i.u o *•• • an d improve d excep t fo rP.3 5

-33

- Th e recertificatio n cost s fo r onboar d system s ar e essentiall yzer o incrementa l t o thos e expecte d wit h improved/exces s evaporativ e control . EP Aexpect s th e onboar d an d evaporativ e regulation s t o hav e th e same effectiv e dates . Sinc e recertificatio n cost s hav e alread ybee nallocate d t o exces s evaporativ e systems , n o additiona l cos t i s neede d here . EPAals o di d no t includ e anadditiona l certificatio n cos t fo r th e onboar d tes t procedure . Th e additiona l procedur e for integrate d system s wil l b e i nlie u o f th e additiona l diurnal s fo r th e improve d evaporativ e system s o nseparat e refueling/evaporativ e systems . Sinc e anadditiona l certificatio n cos t wa s include d there , non e i s include d fo r th e integrate d onboar d systems . EPAdi d no t re-evaluat e th e cos t fo r facilit y modification s fo r th e supplementa l proposal . Th e valu e use d i n th e origina l onboar d proposa l wa s adjuste d fo r inflatio n only , resulting i na 4 5 cen t pe r vehicl e cos t (i nRPE ) whe namortize d ove r a te nyear-period . EPAals o di d no t re-evaluat e th e system s engineering cost s othe r tha nt o adjus t i t fo r inflation . Thes e cost s wer e amortize d ove r 5 years . However , sinc e th e system

ha s bee nsimplified , th e origina l cos t i s probabl yconservative .P.3 6

-34

- C . RecoveryCredit s Th e following . discussio no nrecoverycredit s (weigh t penalt yan

d fue l recovery ) i s specifi c fo r eac hsystem . Ane t recoverycredi t ha s two components : a fue l recoverycredi t an d a weigh t penalty . Th e fue l recoverycredi t account s fo r th e fue l tha t i s save d whe nfue l vapor s ar e capture d b ya vapo r recoverysysteman d utilized . Th e weigh t penalt yaccount s fo r a los s i nfue l econom ydu e t o th e sligh t increas e i nvehicl e weigh t adde d b

yth e vapo r recoverysystem . Th e ne t recovery credi t i s th e differenc e betwee nth e mone ysave d from fue l recoveryan

d th e increase d fue l consumptio ncos t t o mov e a slightl yheavie r vehicle . Th e recoverycredit s fo r exces s evaporativ e system s wil l b e discusse d first . Recoverycredit s fo r improve d evaporativ e system s an d onboar d system s wil l follow . 1 . Exces s Evaporativ e System Ther e wa s n o weigh t penalt yassociate d wit hth e exces s evaporativ e systemo f th e origina l volatilit yproposa l sinc e ther e wer e n o change s necessaryi nvehicl e hardwar e a t 9. 0 RV P fue l whic hwoul d resul t i na weigh t penalty . Th e fue l recover y credi t fo r thes e system s i s a functio no f no t onl ychange s t o th e vehicl e contro l syste mbu t als o o f chang e i ncommercia l fue l volatilit y(bot hth e matching o f in-us e an d certificatio n fue l RV P and th e RV P leve l a t whic hthi s i s done) . Th e portio n o f th e exces s evaporativ e fue l recoverycredi t du e solel yt o vehicl e control s i s difficul t t o determine . Also , i f th e exces s evaporativ e fue l recoverycredi t i s included , the n th e increas e i nlifetime fue l cos t t o th e vehicl e owne r du e t o commercia l fue l volatilit ycontro l mus t als o b e included . Sinc e th e purpos e o f thi s analysi s i s onl yt o determin e vehicl e contro l systemcost s an d no t volatilit ycontro l costs , th e exces s evaporativ e fue l recoverycredi t wa s no t include d here . 2 . Improve d Evaporativ e Svstem s Th e ne t recoverycredit s fo r th e improve d evaporativ e syste m wer e calculate d fo r 9. 0 ps i RVP fuel . Th e weigh t penalt ywil l b e discusse d first . (i ) Weigh t Penalt y Th e weigh t penalt yfo r th e improve d evaporativ e systemwa s calculate d usin g th e sam e metho d a s wa s use d i nth e origina l onboar d proposal . Th e component s whic hwer e include d i nth e weigh t calculatio nar e th e canister , vapo r lines , an d th e vapo r vent/rollove r valve . Acarbo ndensit yo f 0.6 6 lb./L . and a bodyweigh t o f 0.44 5 pound s fo r a 1. 5 lite r caniste r ar e th e same value s use d i nth e origina l onboar d proposal . Th e body weigh t o f othe r cylindrica l caniste r size s i s assume d t o b e proportiona l t o th e rati o o f th e square s o f th e caniste rP.3 7

-35

- radii . (The squar e o f th e radiu s fo r a 1. 5 L canister , assuming th e heigh t t o b e equa l t o th e "diameter , i s 38. 5 cm 2 ) . Table s H Aan d H B showth e calculation s for th e chang e i ncaniste r weight s betwee nth e improve d an d exces s evaporativ e systems . Th e calculation s showing th e chang e i n weigh t du e t o th e increase d diamete r o f th e vapo r line s ar e show ni nTable s 12 Aan d 12B . Ther e i s n o differenc e i nweigh t betwee nth e improve d evaporativ e vapo r vent/rollove r system valv e an

d th e revise d onboar d systemvalve . Also , EP Adi d no t subtrac t th e weigh t o f an ypossibl e curren t systemven t valv e fromtha t o f th e improve d evaporativ e valv e s o tha t th e ful l valv e weigh t wa s allocate d t o th e improve d evaporativ e system . Th e same weigh t wa s use d a s tha t whic hwa s measure d fo r th e valv e o nth e origina l onboar d proposa l system . Thi s i s a conservativ e estimat e sinc e th e origina l onboar d valv e wa s a heavie r fillnec k mounte d valv e mad e o f stee l whil e th e improve d evaporativ e valv e i s plasti c an d mounte d o nth e tank . Th e value s belo whav e bee nweighte d b ysale s fo r singl e an d dua l fue l tanks .Tabl e 11A Evaporative Syste

m Caniste r Weights , LDVs an dLDTs ; 9. 0 ps i RVP fuel . Caniste r Carbo n+ Caniste r Bod y = Siz e Weigh t Materia l Weigh t Tota l Caniste r Weigh t LDV s Exces s Evaporativ e Syste m 1. 3 L ImprovedEvaporative Syste m 2. 7 L 0. 9 lbs . 0. 4 lbs . 1. 3 lbs .

1. 8 lbs . 0. 7 lbs . 2. 5 lbs . Incrementa l Caniste r Weigh t fo r ImprovedEvaporative Syste m 1. 2 lbs . LDT s Singl e Tank Exces s Evaporative Syste m 1. 7 L ImprovedEvaporative Syste m 3. 9 L 1. 1 lbs . 0. 5 lbs . 1. 6 lbs .

2. 6 lbs . 0. 8 lbs . 3. 4 lbs . Incrementa l Caniste r Weigh t fo r ImprovedEvaporative Syste m 1. 8 lbs . Dua l Tank Exces s Evaporativ e Syste m 2 § 1. 7 L ImprovedEvaporative Syste m 2 § 3. 9 L 2. 2 lbs . 1. 0 lbs . 3. 2 lbs .

5. 2 lbs . 1. 6 lbs . 6. 8 lbs . Incrementa l Caniste r Weigh t fo r ImprovedEvaporative Syste m 3. 6 lbs . i C*t N

LD T Weighte d(singl e anddual ) = (80%)(1. 8 lbs. ) +(20%)(3. 6 lbs ) = 2. 2 lbs .

o oTabl e H B Evaporative Syste

mCaniste r Weights , HDGVs ; 9. 0 ps i RV

P fuel .

Exces s Evaporative Syste m (Fro mOrigina l Volatility Proposal . Averag e o f al l HDG V classes , an

d bot h singl e an

d dua l tanks ) Caniste r Carbo n+ Caniste r Bod y Siz e Weigh t Materia l Weight 4. 0 L 2. 6 lbs . 0. 9 lbs . Tota l Caniste r Weigh t 3. 5 lbs .

Improved Evaporative Syste m Clas s li b Singl e Tan

k 4. 3 L 2. 8 lbs . 0. 9 lbs . 3. 7 lbs . Dua l Tan

k 2 @ 4. 3 L 5. 6 lbs . 1. 8 lbs . 7. 4 lbs . Weighte d (Singl e an d Dual ) = (80%)(3. 7 lbs ) + (20%)(7. 4 lbs ) = 4. 4 lbs . Clas s li bIncrementa l Caniste r Weight for Improved Evaporative Syste m= 4. 4 - 3. 5 Clas s V I Singl e Tan

k Dua l Tan

k 7. 0 L

2 & 10. 1 L 4. 6 lbs .

13. 4 lbs . 1. 2 lbs .

3. 2 lbs . =0. 9 lbs . 5. 8 lbs . 16. 6 lbs . Weighte d (Singl e an d Dual ) = (85%)(5. 8 lbs. ) + (15%)(16. 6 lbs ) = 7. 4 lbs . i

Clas s V I Incrementa l Caniste r Weigh t for Improved Evaporative Syste m= 7. 4 - 3. 5 =3. 9 lbs .P.4 0

-38

- Tabl e 12A improve d Evaporativ e SvstemVapo r Lin e Weights ; LDVs an d LDT s

Exces s Evaporativ e Purg e Lin e 2 ft . o f 1/4 " I-D
- Steel : l ft . o f 1/4 " I.D . Rubbe r 2 ft . X0.0 6 lb/f t 1 ft . X0.0 8 lb/f t 0.1 2 lb 0.0 8 lb 0.2 0 lb Improve d Evaporativ e Fue l Tank Ven t Lin e 2 ft . o f 3/8 " I.D . Steel : 1 ft . o f 3/8 " I.D . Rubbe r 2 ft . X0.1 2 lb/f t 1 ft . X0.1 2 lb/f t 0.2 4 lb 0.1 2 l b 0.3 6 lb

Tota l Incrementa l Weigh t LDV s an d LD T Singl e Tank 0.3 6 lb- 0.2 0 lb- 0. 2 lbs . Tota l Incrementa l Weigh t LDT Dua l Tank ^ (80%)(0.2 0 lb ) + (20%)(0.4 0 lb ) - 0. 2 lbs .P.4 1

-39

-

Tabl e 12 B Improve d Evaporativ e SystemVapo r Lin e Weights ; HDGV s Ne t incrementa l weigh t o f the improve d .evaporative systemvapo r line s i s th e differenc e i nweigh t betwee nth e 1/2 " I.D . rubbe r fue l tank vapo r ven t lin e o nth e improve d evaporativ e system an d th e 3/8 " I.D . rubbe r fue l tank vapo r ven t lin e o nth e exces s evaporativ e system . Exces s Evaporativ e System Fue l Tank Vapo r Ven t Lin e Clas s lib : Clas s VI : Singl e Tank 3/8 "

Dua l Tank s Singl e Tank 3/8 " Dua l Tank s 8 ft . X0.1 2 lb/ft . = 0.9 6 lbs . 2 Xsingl e = 1.9 2 lbs . 1 5 ft . X0.1 6 lb/ft . =1. 8 lbs , 2 Xsingl e = 3. 6 lb s Improve d Evaporativ e System Fue l Tank Vapo r Ven t Lin e Clas s lib : Clas s VI : Singl e Tank 1/2" :

Dua l Tank s : 8 ft . X0.1 6 lb/ft , 2 Xsingl e Singl e Tank 1/2" : 1 5 ft . X0.1 6 lb/f t Dua l Tank s : 2 Xsingl e 1.2 8 lbs , 2.5 6 lbs . 2.4 0 lbs , 4.8 0 lbs , Tota l Incrementa l Weigh t o f Vapo r Line s Clas s lib : Singl e Tank : 1.2 8 lbs . - 0.9 6 lbs .

Dua l Tank 2.5 6 lbs . - 1.9 2 lbs . Weighted : (80%)(0.32 ) + (20%)(0.64 ) Clas s VI : Singl e Tank : 2. 4 lbs . - 1. 8 lbs .

Dua l Tank : 4. 8 lbs . - 3. 6 lbs . Weighted : (85%)(0.6 ) + (15%)(1.2 ) 0.3 2 lbs , 0.6 4 lbs , 0.4 0 lbs , 0 . 6 lbs . 1. 2 lbs . 0. 7 lbs .-40

- Vapo r Vent/Rollove r Valv e Weigh t LD V = 0. 4 lb s LDT : (80%)(0.4 ) +(20%)(0.8 ) ~ 0. 5 lb s HDG V lib : (80%)(0.4 ) + (20%)(0.8 ) - 0. 5 lb s HDG V VI : (85%)(0.4 ) + (15%)(0.8 ) - 0. 5 lb s Th e tota l chang e i nvehicl e weigh t an d th e corresponding effec t o nfue l econom yca nno wb e calculated . Th e same forma t a s tha t use d i nth e origina l onboar d proposa l wa s used . Componen t LD V LD T li bV I Caniste r (Carbon , Body ) 1. 2 lb s 2. 2 lb s 0. 9 lb s 3. 9 lb s Vapo r Line s 0. 2 0. 2 0. 4 0. 7 Valv e 0. 4 0. 5 0. 5 0. 5 Tota l Weigh t (lbs ) 1. 8 2. 9 1. 8 5. 1 Weigh t Multiplicatio n Facto r (1.1 ) 2. 0 3. 2 2. 0 5. 6 Ave . Vehicl e Weigh t (lbs ) 3,08 2 3,83 2 9,25 0 22,50 0 Percen t Chang e i nWeigh t 0.064 % 0.083 % 0.021 % 0.025 % Sensitivit yFacto r (dimensionless ) -0.32 9 -0.40 2 -0.40 2 -0.40 2 Percen t Chang e i nFue l Econom y(mpg ) -0.021 % -0.033 % -0.009 % -0.010 % Projecte d Fue l Econom y(mpg ) 24.6 1 18.4 3 11.1 6 6.0 7 Projecte d Avg . Lif e (miles ) 100,00 0 120,00 0 110,00 0 110,00 0 Lifetim e Fue l Consumptio n (gal ) 4,06 3 6,51 1 9,85 7 18,12 2 Lifetim e Weigh t Penalt y (gal ) 0. 9 2. 2 0. 8 1. 8 HDGV s (weighted ) = 1. 1 ga l Th e tota l weigh t penalt ycos t ove r th e lifetime o f th e vehicl e ca nno wb e calculate d usin g th e same discoun t factor s an d yearl yfue l recoveryfraction s a s use d i nth e origina l onboar d proposal . Afue l pric e o f $0.8 2 pe r gallo ni s used , whic hi s th e sam e a s wa s use d i nth e origina l volatilit y proposal . Thi s pric e doe s no t includ e taxe s an d i s base d upo n a crud e oi l pric e o f $2 0 pe r barrel . Th e resultin g weigh t penalt yis : $0.4 8 fo r LDVs , $1.1 6 fo r LDTs , an d $0.6 0 fo r HDGVs .-41

- (ii ) Fue l RecoveryCredi t Th e fue l recoverycredit s ( $ pe r vehicl e lifetime ) ar e base d o nth e emissio nfacto r reduction s (gram s H C pe r mile ) resulting fromimprove d evaporativ e contro l systems . Thes e emissio nfacto r reductions , show ni nTabl e 13 , wer e take n from a recen t EP Aanalysis.[5 ] I t wa s assume d tha t 8 0 percen t o f curren t running los s emission s woul d b e controlle d byth e implementatio n o f improve d evaporativ e controls . Th e tota l emissio nfacto r reduction s fo r eac hvehicl e typ e wer e the n multiplie d bythei r expecte d lifetime mileage s discounte d a t a rat e o f 1 0 percen t (6542 0 fo r LDVs , 8093 2 fo r LDT s an d 7171 5 fo r HDVs ) t o yiel d tota l discounte d lifetime emissio n reductions . Thes e emissio nreduction s (assume d t o b e al l butane ) wer e the nvalue d a t $290.3 2 pe r to nbase d o nwor k performe d i nth e origina l volatilit ycontro l proposal . (Thi s assume s a cos t pe r gallo no f gasolin e o f $0.8 2 an d a combustio n efficienc yo f th e hydrocarbo nvapo r equivalen t t o tha t o f liqui d fuel ; i.e. , a nevaporativ e recoveryfacto r o f 1.0. ) Th e fue l recoverycredit s o na vehicl e lifetime basi s ar e then : Vehicl e Typ e 9 RV P Fue l 11. 5 RV P Fue l LD V $12.3 1 $42.8 3 LD T $20.6 7 $63.3 5 HDV $38.7 4 $96.0 7 Th e decreas e i nth e credi t wit h9 RVP fue l result s fromth e fac t tha t a grea t dea l o f evaporativ e emissio nreduction s occu r a s a resul t o f volatilit ycontrol . Thes e volatility-relate d emissio nreduction s ar e no t reflecte d i nth e calculation s above . Th e ne t recoverycredi t fo r th e improve d evaporativ e system o f eac hvehicl e typ e i s th e differenc e betwee nth e fue l recoverycredi t and th e weigh t penalt yfo r tha t system . Thes e value s ar e show

ni nTabl e IB . 3 . Onboar d System Th e ne t recoverycredit s use d i nth e origina l onboar d proposa l wer e adjuste d t o accoun t fo r th e change s mad e i n th e supplementa l proposal . Sinc e th e fue l tan k size s and fue l economie s di d no t chang e i nth e reproposal , th e quantit yo f fue l recovere d wa s no t changed . However , th e simplifie d system ha s fewe r component s tha nbefor e an d eve nresult s i nth e remova l o f th e externa l ven t lin e fo r LDVs , LDT s and Clas s li b HDGVs . Th e caniste r i s onl yslightl ylarge r tha nth e caniste r propose d fo r th e enhance d evaporativ e system . Therefore , EP A consider s th e weigh t penalt yo f onboar d system s incrementa l t o improve d evaporativ e system s t o b e essentiall yzero . I nfact , ther e coul d b e a sligh t weigh t decrease .P.4 4

-42 - Tabl e 1 3 EmissionFactor Reduction s Resulting Fro m Improve

dEvaporativ

e Controls[5 ] 9 RV P Fue l LD V LDT HD

V Hig hTemperature Diurna l Evaporativ

e Emission s (g/mi ) 0.3 4 0.5 5 1.4 4 Runnin gLosse s (g/mi ) 0.24 8 0.24 8 0.24 8 Tota l EmissionFactor (g/mi ) 0.58 8 0.78 9 1.68 8 DiscountedLifetim e Emission s (kg ) 38. 5 64. 6 121. 0 11. 5 RV P Fue l LD V LDT HD

V Hig hTemperatur e Diurna l Evaporative Emission s (g/mi ) 0.6 7 1.0 7 2.8 1 Runnin gLosse s (g/mi ) 1.37 6 1.37 6 1.37 6 Tota l EmissionFactor (g/mi ) 2.04 6 2.44 6 4.18 6 DiscountedLifetim e Emission(kg ) 133. 0 198. 0 300. 2P.4 5

-43

- Sinc e ther e i s n o weigh t penalty , th e ne t recoverycredi t i s base d solel yo nth e fue l recoverycredit . Th e fue l cos t wa s adjuste d from

$o.98/ga l t o $0.82/ga l i norde r t o b e consisten t wit hth e valu e use d i nth e origina l volatilit yproposal . Th e discoun t factor s an d yearl yfue l recoveryfraction s use d i nth e origina l proposa l wer e als o applie d i nthi s analysis . Th e fue l recoverycredit s fo r 9. 0 ps i RVP fue l ar e showni nTabl e 14 , along wit hth e quantit yo f fue l save d durin g th e vehicle' s life . Thes e credit s ar e als o show ni nTabl e IC .P.4 6

-44

- Tabl e 1 4 Fue l RecoveryCredit s fo r Onboar d systems * 9. 0 ps i RVP Fue l Saving s Vehicl e (gal/life ) (1988$ ) LD V 7. 8 $4.2 0 LDT 12. 6 6.6 5 HDG V 23. 6 12.6 0 value s les s tha n$1 0 wer e rounde d of f t o th e neares t nickel . Value s greate r tha n$1 0 wer e rounde d of f t o th e neares t dime .P.4 7

-45 - Summar y The cos t analysi s fo r the supplementa l proposa l fo r improve devaporativ

e an donboar

dsystem

s wer e changedonl y wher e necessar

y t o reflec t ne

w requirements , change s indesig n concept s an

dimprove

dmodeling . Component s an dother cos t area s no t affectedwer e onl y adjustedfo

r inflatio

nso tha t al l value s are i

n198 8 dollars . The resultin gcos t estimate s represent "typical " vehicles . The actua l cos t fo r individua l model s wil l vary . A summar

y of the cost s fo r exces s evaporative , improve devaporativ

e an drevisedonboar

dsystem

s i s presentedinthe followin gparagraphs . Thes e syste m cost s wer e show

ni nTable s I

A throug hID . The estimatednet cost s fo r exces s evaporativ e system

s incrementa l to current evaporativ e system

s when9. 0 RV

P fue l i s usedare $1.45 , $1.8 5 an d$3.3 5 fo

r LDVs , LDT s an

dHDGVs respectively . Thes e cost s are entirel y due t o vehicl e cos t increase s sinc e ther e i s no incrementa l weight penalty an dthe fue l recover

y credi t ca

nnot be includedi nthi s analysi s fo r reason s alread

y explained . However , thi s i s conservative sinc e som e of th

e recover

y credi t i s attributabl e to vehicl e charges . Th

e sale s weightedne t incrementa l cos t fo r exces s evaporative systems i s $1.6 0 inRPE . The estimatedcos t fo r improvedevaporative systems incrementa l t o exces s evaporativ e system

s i s $9.65 , $13.40 , an d $11.2 5 fo

r LDVs , LDTs , an

dHDGVs , respectively , fo r 9. 0 ps i RV

P certificationfuel . If the ne t recover y credit s are included , the improve

devaporativ

e system

s shoul dresul t ina ne t incrementa l saving s of $2.15 , $6.1 0 an d$26.9 0 fo

r LDVs , LDT s an dHDGVs respectively . The ne t saving s weightedb y vehicl e clas s i s $3.70 . The estimatedcos t fo r simplifiedonboardsystems incrementa l t o improve devaporative systems i s $0.90 , $1.50 , an d$5.2 0 fo

r LDVs , LDTs , an

dHDGVs respectivel y (fo r 9. 0 ps i RV P certificationfuel) . I f the ne t recover y credit s ar e included , th

e onboardsystem

s shoul dresul t ina ne t saving s fo r the vehicl e owner . The estimatedne t incrementa l saving s ar e $3.30 , $5.1 5 an d$7.4 0 fo

r LDVs , LDTs , an dHDGVs , respectivel y

(9. 0 ps i RVP) . The ne t incrementa l saving s weightedb

y vehicl e clas s sale s i s $3.90 . The tota l vehicl e cost s fo r the onboardrefuelin gan d evaporative syste m change s (bothexces s an dimprove

d evaporative ) are $12.00 , $16.7 5 an d$19.8 0 fo

r LDVs , LDT s an

d HDGVs respectivel y incrementa l t o current evaporative systems . I f th e net recover

y credit s are includeda ne t saving s i s realizedb

y the vehicl e owner of $4.00 , $9.4 0 an d$30.9 5 inthe thre e vehicl e classes . The sale s weightedne t incrementa l saving s i s $6.00 .P.4 8 

# v - -46 - Reference s 1 . Draf t Regulator y Impac t Analysis , "Contro l of Gasoline Volatility an dEvaporative HydrocarbonEmission s fro m Ne w Motor Vehicles, " U.S . EPA , Offic e of Ai r an dRadiation , Offic e of Mobil e Sources , Jul y 1987 . Publi c Docke t A-85-22 , III-B-1 . 2 . "Evaluatio

nof Ai r Pollutio nRegulator

y Strategie s fo r Gasoline Marketin gIndustr

y - Respons e t o Publi c Comments, " U.S . EPA , offic e o f Ai r an dRadiation , Offic e o f Ai r Quality Plannin gan dStandards , an dOffic e of Mobil e Sources , (EPA450/3-84-012c) , July 1987 . 3 . Draf t Regulator y Impac t Analysis , ProposedRefuelin g EmissionRegulation s fo r Gasoline - FueledVehicle s — Volum

e I I - Additiona l Analysi s of OnboardControl s (EPA-450/3-87-001b) , U.S . EPA , Offic e of Ai r an dRadiation , Offic e of Ai r Quality Plannin

gan dstandards , an

dOffic e of Mobil e Sources , Jul y 1987 . 4 . "P

T Mode l Descriptionan dUser s Guide, " Davi dB . Bartus , U.S . EPA , SDSB , Augus t 10 , 1988 . 5 . "Effec t of RunningLosse s an dExces s Evaporative Emission s o

nFutur e VOC EmissionInventories, " Memorandu m fro m RichardRykowski , EPA/OMS/ECTD/SDSB , t o the Record , Decembe r 22 , 1988 .