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# OAR Box 1259 Prepped by Ollie Stewart



## Document

Number: 

# 5 ) ll-A- 1

Docket Number: 

# A-91-7 4

Printed 5/27/20083:12:26

PM Sheet 5of 210P. 2 

# A-9/-7*/ 

# ynr-4-1

Januar y19 , 199 3



## Pairtt



# Protect5©oi ] Ag®oi]©

f
4 0 CF R Par t S

® Los t oi f Regulate d Substance s an d Threshold s fo rAccidenta l Releas e Prevention ; Requirement s fo rPetitions ; Propose d Rul e

CJAAJ Recycled/Recyclabl e

" ^ Printe d wit h Soy/Canol a In k o n pape r tha t contain s a t leas t 50 % recycled fibe r <sA-4 aP. 3

510 2 Federa l Registe r/ Vol . 58 , No . 1 1 /

Tuesday , Januar y 19 , 199 3 / Propose d Rule s
ENVIRONMENTA L PROTECTIO N AGENC Y
4 0 CF R Par

t 6 8 [A-91-7468 ; FRL-455J-3 ] List of Regulate d Substance s an d Threshold s fo r Accidenta l Releas e Prevention ; Requirement s fo r Petition s unde r Sectio n 112(r ) of th e Clea n Ai r Act a s Amende d AGENCY : Environmenta l Protectio n Agenc y (EPA)
. ACTION : Propose d rule . SUMMARY: Th e Clea n Ai rAc t Amendment s o f

1990 , signe d int o la w o n Novembe r15,1990 , includ e provision s fo rchemica l acciden t prevention
. Th e Environmenta l Protectio n Agenc y i s proposin g alis to f regulate d substance s an d threshol d quantitie s a s require d unde rsectio n 112(r ) o f th e Clea n Ai rAc ta s amended . Th e lis ti s compose d o f thre e distinc t categories : lis to f

10 0 toxi c substances , lis to f 6 2 flammabl e substance s (gase s an d volatil e liquids) , an d commercia i explosive s a s define d b y th e Departmen t o f Transportatio n (DOT ) i n Divisio n 1. 1 (explosive s wit h mas s explosio n hazard) ; individua l explosive s ar e no t included
. Th e lis tan d threshol d quantitie s wil l determin e th e nee d fo r owner s an d operator s o f facilitie s t o compl y wit h futur e regulation s addressin g th e preventio n an d detectio n o f accidenta l release s t o b e propose d later . EP A i s als o publishin g th e requirement s fo rth e petitio n proces s tha twil l b e use d t o ad d o rdelet e chemical s fro m th e fina l list
. DATES : Comment s mus tb e submitte d o n o rbefor e Marc h 22,1993
. EP A plan s t o hol d a tleas ton e publi c hearing ; date , tim e an d locatio n wil l b e publishe d shortl y i n th e Federa l Register
. ADDRESSES : Comment s ma y b e maile d o rsubmitte d to : Environmenta l Protectio n Agency , Ai rDocke t(LE-131) , Attn : Docke tNo . A-91-74 , Watersid e Mall , 40 1 M St
. SW. , Washington , D C 20460
. Comment s mus tb e submitte d i n duplicate
. Docket: Supportin g informatio n use d i n developin g thi s propose d rul e i s containe d i n Docke tNo . A-91-74
. Thi s docke ti s availabl e fo rpubli c inspectio n an d copyin g betwee n 8:3 0 a.m . an d 1 2 noon , an d betwee n 1:3 0 an d 3:3 0 p.m. , Monda y throug h Frida y a tth e addres s liste d below . A reasonabl e fe e ma y b e charge d fo rcopying
. FO RFURTHE

RINFORMATIO

N CONTACT : Vaness aRodriguez , (202 ) 260-7913 , Chemica l Emergenc y Preparednes s aa d Preventio n Office , OS-120 , Environmenta l Protectio n Agency , 40 1 M S
. SW. , Washington , D C 20460 , o r th e Emergenc y Plannin g an d Communit y Right-to-Kno w Ho tLin e a t 1-8S0-535-O202
. SUPPLEMENTAR

Y INFORMATION

: I. Introductio n A , Statutor y Authorit y B . Backgroun d II . Qea n Ai rAc tAmendment s o f 199 0 {CAAA ) III. Lis to f

Substance s an d Threshold s A
. Introductio n B . Factor s Considere d i n Definin g Lis t Criteri a C
. Criteri aOption s Considere d D . Lis to f Substance s E . Threshol d Quantitie s IV . Othe rIssue s A
. Stat e Program s B . OSHA' s Lis to f

Highl y Hazardou s Chemical s C
. Relationshi p t o EPCR A (SARA Titl e III

) Sectio n 362/30 3 D . Agricultura l Nutrien tExemptio n E . Informatio n Gatherin g Effort s V . Petition s fo rAddition s an d Deletion s A
. Informatio n Require d from Petitione r B . Petitio n Proces s VI . Discussio n o f

th e Propose d Rul e VII . Require d Analyse s A.E.O
. 1229 1 B . Regulator y Flexibilit y Ac t C
. Paperwor kReductio n Ac t I . Introductio n A. Statutory Authority Thi s notic e o f

propose d rulemakin g (NPRM ) i s bein g issue d unde rsectio n 11* ) ofth e Clea n Ai rAc t(CA A o rAct ) a s amende d (4 2 U.S.C
. 7412 , 7601)
. B. Background Publi c awarenes s o f

th e potentia l dange rfro m accidenta l release s o f hazardou s chemical s ha s increase d ove r th e year s a s seriou s chemica l accident s hav ® occurre d aroun d th e worl d (e.g. , th e 197 4 expdoste n i n Flixborough , England , an d th e 197 6 releas e o f dioxi n i n Seveso , Italy)
. Publi c concer n intensifie d followin g th e 198 4 releas e o f metfiy l isocyanat e i n Bhopal , India , whic h kille d mor e tha n 2,00 0 peopl e livin g nea rth e facility
. A subsequen t releas e from achemica l facilit y i n Institute , Wes tVirginia , sen tmor e tha n 10 0 peopl e t o th e hospita l an d mad e American s awar e tha tsuc h incident s ca n an d d o happe n i n th e Unite d States
. I B respons e t o thi s publi c concer n an d th e hazard s tha texist , th e U.S
. En^ronmenta l Protectio n Agenc y (EPA ) bega n it s Chemica l Emergenc y Preparednes s Program (CEPP ) i n 1985 , a s far to f

th e Agency' s Ai rToxic s Strategy
. CEP

Pwa s avoluntar y progra m t o encourag e stat e an d loca l authoritie s t o identit y hazard s i n thei rarea s an d t o pla aforchemica l emergenc y respons e actions
. In 1986 , Congres s adopte d man y ofth e element s o f CEP Pi n th e Emergenc y Plannin g an d Communit y Right-to-Kno w Ac to f

198 6 (EPCRA) , als o know n a s Titl e II

I o f th e Superfun d Amendment s an d Reauthorizatio n Ac t o f 198 6 (SAR A Titl e III)
. EPCP A (SARA Titl e III ) require s state s t o establis h stat e ah d loca l emergenc y plannin g groups , namely , th e Stat e Emergenc y Respons e Commission s (SERCs ) an d th e Loca l Emergenc y Plannin g Committee s (LEPCs) , t o develo p emergenc y respons e plan s fo reac h community
. EPCR A (SARA Titl e III

) require s facilitie s t o provid e informatio n o n th e hazardou s chemical s the y hav e o n site ; th e informatio n collecte d i s availabl e t o th e publi c throug h th e SERC/LEP C structure . Thi s informatio n form s th e foundatio n o f

bot h th e emergenc y respons e plan s an d th e public-industr y dialogu e o n risk s an d ris kreduction
. EPCR A (SAR A Titl e IU

) di d no t mandat e tha tfacilitie s establis h acciden tpreventio n programs . However , Congres s acknowledge d th e importanc e o f acciden tpreventio n b y requirin g EPA , unde rEPCR

A (SARA Titl e III

) sectio n 305(b) , t o conduc tarevie w o f emergenc y system s t o monitor , detect , an d preven tchemica l accidents
. Th e fina l repor tt o Congress , Review of Emergency Systems (EPA , 1988) , conclude d tha tth e preventio n o f accidenta l release s require s a n integrate d approac h tha tconsider s technologies , operations , an d managemen tpractices
. Th e repor t emphasize d th e importanc e o f managemen tcommitmen tt o safety
. Althoug h EPCR

A (SARA Titl e III

) di d no tdirectl y addres s acciden t prevention , EP

A recognize d tha t prevention , preparedness , an d respons e form acontinuum
. Therefore , i n 1986 , EP A establishe d achemica l acciden t preventio n progra m t o collec t informatio n o n chemica l accident s an d wor kwit h othe rgroup s t o increas e knowledg e o f

preventio n practice s an d encourag e industr y t o improv e safet y at facilities
. Unde rthi s program , EP A develope d it s Accidenta l Releas e Informatio n Program (ARIP) t o collec t datao n th e cause s o f

chemica l accident s an d th e step s facilitie s tak e t o preven t recurrences . EP

A als o develope d a progra m fo rconductin g chemica l safet y audit s atfacilities
. Throug h th e audi t program , EP

A headquarter s an d regiona l staf f a s wel l a s stat e an d loca l official s learne d abou tintegrate d approache s t o proces s safet y from facilities
. EP A ha s als o worke d wit h trad e associations , professiona l organizations , labor , environmenta l groups , an d othe r Federa l agencie s t o determin e ho w bes t t o reac h smalle roperations , whic h th e sectio n 305(b ) stud y indicate d ar e les sP. 4

Federa l Registe r

/ Vol

. 58 , No

. 1 1 /

Tuesday , Januar y 19 , 199 3 / Propose dRule s 510 3

aware o f risk s tha n larger

facilities

. EP

A ha s als o bee n a n activ e participan t i n internationa l effort s relate dt o chemica l acciden t prevention , particularl y throug hth e Organizatio n fo r Economi c Cooperatio n an dDevelopmen t (OECD) , whic hha s hel dfiv e internationa l workshop s from198 9 throug h199 1 t o discus s issue s relate dt o acciden t prevention , preparedness , an dresponse , an dha s develope dguideline s fo r membe r countries

. In additio n t o EPA' s wor

k i n thi s area , othe r agencie s an dstate s hav e develope dprogram s relate dt o chemica l acciden t prevention

. Recently , th e Occupationa l Safet

y an dHealth Administratio n (OSHA

) ha s promulgate dafinal rul e o n chemica l proces s safet

y management

(5 7 F R6356 , February 24,1992)

. Thre e states—Ne w Jersey , California , an dDelaware—hav e adopte dregulation s requirin g facilitie s t o prepar e an dimplemen t ris k managemen t

plans

. A fourt

hstate , Nevada , ha s recentl y enacte dlegislatio n o n chemica l proces s safet y management

. Professional an dtrad e organization s hav e als o develope dprogram s i n thi s area
. Fo r example , th e Cente r

fo r Chemical Proces s Safet

y ofth e American Institut e o

f Chemica l Engineer s ha s publishe dguidanc e o n th e managemen t

o f chemica l proces s safety

. Th e Chemica l Manufacturers ' Associatio n ha s adopte daResponsibl e Care TM program , whic hal l member s mus t compl y wit ht o maintai n membership

. Th e America n Petroleu m Institut e ha s develope dasimilar program , Managemen t

of Proces s Hazards ; Recommende dPractic e 75 0 (R P 750) , fo r it s members

. In 1982 , th e European Community adopte dth e Seves o Directiv e (82/501/EEC , a s amended) , whic hrequire s facilitie s handlin g certai n chemical s t o develo p a safet y repor t tha t i s similar

t o aris k managemen t

plan

. II

. Clea n Ai r

Ac t Amendment s o f

199 0 (CAAA ) In th e Clea

n Ai r Ac t Amendment s o

f 199 0 (CAAA) , signe dint o la w o n November

15,1990 , Congres s adde d paragrap h(r

) t o sectio n 11 2 fo

r th e preventio n o

f chemica l accidents

. Th e goal s o f th e chemica l acciden t preventio n provision s ar e t o focu s o n chemical s tha t

pos e asignifican t

hazar d t o th e communit y shoul da n acciden t occur , t o preven t

thei r accidenta l releas e an dt o minimiz e th e consequence s o f suc hreleases

. Sectio n 112(r) ofth e CA

A ha s a numbe r o f provisions

. It

establishe s a genera l dut y fo

r owner s an doperator s o

f stationary sources , wh o produce , process , handle , o r

stor e substance s liste dunde r sectio n 112(r)(3 ) an dan y othe r extremel y hazardou s substances , t o compl y an dperfor

mspecifi c activitie s t o preven t

an dmitigat e accidenta l releases

. Th e genera l dut y requirement s appl y t o stationary source s regardles s o

f th e quantit y o

f substance s manage da

t th e facility

. Activitie s suc h a s hazard s identificatio n usin g appropriat e hazar dassessmen t techniques , designing , maintainin g an d operatin g asaf

e facility , an dminimizin g th e consequence s o

f accidenta l release s if the y occu r

woul db e essentia l activitie s tha t

mus t b e performe dt o satisf y th e genera l dut y requirements

. Owner s an doperator s o

f thes e stationar y source s are require di n th e CA A t o conduct , i n th e sam e manne r an dt o th e sam e exten t

a s OSHA' s genera l dut y claus e i n sectio n 65 4 o f titl e 2 9 o f th e Unite dState s Code , thes e activitie s a s amatte r

o f genera l busines s practice

. Sectio n 112(r)(3 ) ofth e CA A require s EP A t o promulgate , b y November 15 , 1992 , alis t

o f at leas t 10 0 substance s ("regulate dsubstances" ) tha t ar e know n t o cause , o r

ma y b e reasonabl y anticipate dt o cause , death , injury , o r seriou s advers e effect s t o huma n healt h or th e environmen t

if accidentall y released

. EP

A i s require dt o se t threshol dquantitie s fo

r eac hliste d substance

. Unde r

CA A sectio n 112(r)(7) , th e Ac t require s EP

A t o promulgate , b y Novembe r

15,1993 , reasonable regulation s an dappropriat e guidanc e t o provid e fo

r th e preventio n an ddetectio n o f accidenta l release s an dfo r response s t o suc hreleases

. Th e acciden t preventio n regulation s wil l appl y t o stationary source s tha t

hav e presen t mor e tha n athreshol dquantit y o f a regulate dsubstance

. Thes e regulation s shal l address , a s appropriate , th e use , operation , repair , an dmaintenanc e o f equipmen t

t o monitor , detect , inspect , an dcontro l releases , includin g trainin g o f personne l i n th e us e an dmaintenanc e o f equipmen t

o r i n th e conduc t

o f periodi c inspections

. Th e regulation s shal l includ e requirement s fo r aris k managemen t

pla n (RMP)

. Th e RM

P shal l includ e ahazar dassessment , a preventio n program , an darespons e program
. Th e propose drul e fo r th e Ris k Managemen t

Programrequirement s wil l b e publishe di n th e Federa l Registe r i n th e future

. Th e Ac t establishe s aChemical Safet y an dHazar dInvestigatio n Boardt o investigat e (o

r caus e t o b e investigated ) chemica l accident s at

facilitie s an d recommen dt o Congress , Federal , state , loca l authorities , an dth e publi c action s tha t can b e take n t o improv e chemica l safety

. Unde r

th e Act , EP

A i s authorize d t o conduc t

studie s relate dt o accidenta l releases , includin g researc ho n hazar d assessments , hydroge n fluoride , an dai r dispersio n modeling

. Th e CAA A als o requir e OSH

A t o promulgat e achemica l proces s safet y rul e (CAA

A sectio n 304 ) t o protec t employee s fromhazard s associate dwit h accidenta l release s o

f highl y hazardou s chemical s i n th e workplace

. OSH A promulgate dafinal rul e (5 7 F R6356 , February 24,1992 ) requirin g achemica l proces s safet

y managemen t

programfo

r an y proces s involvin g ahighl y hazardou s chemica l at

o r abov e a specifie dthreshol dquantity

. Th e rul e applie s t o alis t

of highl y hazardou s toxic an dreactiv e substance s at particula r threshol dquantities , flammabl e liquid s o r

flammabl e gase s i n quantitie s of

10,00 0 pound s o r

mor e an d t o th e manufactur e o

f explosive s an d pyrotechnics

. III

. Lis t o f Substance s an dThreshold s A. Introduction Th e Ac t require s EP

A t o promulgate , n o late r tha n Novembe r

15,1992 , a n initia l lis t o f at leas t 10 0 substance s that , i n th e even t

o f a n accidenta l release , ar e know n t o caus e or

may reasonabl y b e anticipate dt o caus e death , injury , or seriou s advers e effect s t o huma n healt h o r th e environment

. An accidenta l releas e i s define dunde r

th e Ac t a s "a n unanticipate demissio n * * * int o th e ambien t ai r from astationar y source. " I n developin g thi s list , EP

A shal l use , bu t i s no t limite dto , th e lis t

o f extremel y hazardou s substance s (EHSs ) promulgate dunde r

EPCR A (SAR A Titl e III) sectio n 302

. Congres s liste dth e followin g 1 6 substance s t o b e include di n th e initia l lis t (th e Chemica l Abstract s Servic e (CAS ) Registr

y numbe r i s provide di n parentheses) : chlorin e (7782-50-5) , ammoni aan danhydrou s ammoni a (7664-41-7) , methy l chlorid e (74-87-3) , ethylen e oxid e (75-21-8) , viny l chlorid e (75-01-4) , methy l isocyanat e (624-83-9) , hydroge n cyanid e (74-90-8) , hydroge n sulfid e (7783-06-4) , toluen e diisocyanate , represente dby : —toluen e 2,4-diisocyanate (584-84-9 ) —toluen e 2,6-diisocyanate (91-08-7 ) —toluen e diisocyanate , mixe d isomer s (26471-62-5 ) phosgen e (75-44-5) , bromin e (7726-95-6)

. anhydrou s hydroge n chlorid e (7647-01

- 0) , hydroge n fluorid e (7664-39-3) , anhydrou s sulfu r

dioxid e (7446-09-5) , an d sulfu r trioxid e (7446-11-9)

.P. 5

510 4 Federa l Registe r/ Vol

. 58 , No

. 1 1 /

Tuesday , Januar y 19 , 199 3 / Propose dRule s
N o ai r pollutan t fo r whic hanationa l primary ambien t

ai r qualit y standar d ha s bee n establishe dshal l b e include d o n th e list , wit hth e exceptio n o f anhydrou s sulfu r

dioxid e an dsulfur trioxide , whic hmus t

b e included

. N o substance s regulate dunde r titl e V I o f th e Ac t a s amende dshal l b e include d o n th e list

. Titl e V

I cover s ozon e depleters , primaril y chlorofluorocarbon s (CFCs) an dhalons

. Th e lis t o f chemical s propose dtoda y will , whe n final , identif

y stationar y source s tha t

wil l b e covere db y chemica l acciden t preventio n regulation s subsequentl y adopte dunde r sectio n 112(r ) ofth e Act

. Th e lis t

o f substance s i s intende dt o focu s accidenta l releas e preventio n effort s o n thos e stationar y source s an dsubstance s tha t pos e significan t

hazard s t o th e community

. EP A strongl y emphasizes , however , tha t th e chemical s propose dtoda y fo r listin g are no t th e onl y substance s tha t

ma y pos e athrea t

t o communitie s upo n release

. Ther e ar e larg e number s o f compound s an dmixture s i n commerc e i n th e Unite dState s tha t

i n specifi c circumstance s coul db e considere dtoxic o r otherwis e dangerous ; however , i t woul dno t

b e feasibl e t o includ e al l suc h substance s an dcircumstances

. Th e propose dlis t

represent s onl y th e firs t ste p towar ddevelopmen t o f a n effectiv e accidenta l releas e preventio n effor t b y facilities

. Withou t

apreliminar y lis t

of thi s kind , i t

woul db e mor e difficul t

fo r facilitie s t o identif

y chemica l hazard s withth e potentia l t o affect th e community

. Thi s lis t

shoul dserv e a s a focu s i n initiatin g preventio n efforts ; i t i s no t alis t o f al l substance s tha t

coul d b e considere dfo

r chemica l acciden t prevention

. Similarly , th e threshol d quantitie s bein g propose dmay no t alway s represen t

aleve l belo w whic hn o hazar dexists

. Althoug hstationar y source s wil l b e require dt o compl y wit h th e provision s fo

r accidenta l releas e prevention onl y if

the y hav e liste d substance s i n quantitie s exceedin g th e threshol dquantity , i t

doe s no t mean that thes e substance s i n smalle r quantitie s represen t

n o potentia l hazar d t o th e community

. Also , stationar y source s hav e agenera l dut y t o compl y an dperfor

mactivitie s t o preven t

an d mitigat e accidenta l release s regardles s o f th e quantit y ofth e substanc e handle d o n site

. EP A i s proposin g alis t

of 10 0 acutel y toxi c substances , 6 2 flammabl e gase s an dvolatil e flammabl e liquids , an dhig h explosive s a s acategory

. Propose d threshol dquantitie s fo

r toxic substance s are base do n arankin g metho dtha t consider s eac hsubstance' s toxicity an d potentia l t o becom e airborn e an d disperse

. Th e propose dthreshol d quantit y fo r flammabl e substance s i s basedo n th e quantit y tha t potentiall y migh t b e involve di n avapo r

clou d explosion

. Th e propose dthreshol d quantit y fo

r hig hexplosive s i s base do n th e quantit y tha t

coul dproduc e potentiall y letha l blas t

wave s froman explosio n at

adistanc e o

f 10 0 meters

. Th e presenc e o

f athreshol dquantit y at astationary sourc e woul db e determine dbase do n th e maximu m quantit y i n asingl e process
. B. Factors Considered

in Defining List Criteria Unde r CA A sectio n 112(r)(4) , th e factor s t o b e considere di n listin g substance s are : (a

) Th e severity o

f acut e advess e healt heffect s associate dwit h accidenta l release s o

f th e substance , (b) th e likelihoo do

f accidenta l release s of th e substance , an d(c ) th e potentia l magnitud e of

huma n exposur e t o accidenta l release s o

f th e substance

. Th e Ac t specifie s tha t

th e Administrato r shal l use , bu t

i s no t limite dto , th e lis t o f extremel y hazardou s substance s (EHSs ) unde r

EPCR A (SAR A Titl e III) sectio n 30 2 fo

r purpose s o

f promulgatin g th e list

. Th e Ac t als o requite s tha t

regulation s establishin g th e lis t shal l includ e an explanatio n o f tiie basi s fo r establishin g th e list

. EP A reviewe danumbe r

o f existin g or propose dchemica l list s associate dwit h othe r acciden t prevention , preparednes s an drespons e program s t o evaluat e criteri afo r listin g regulate dsubstances

. Thes e lists , whic hare relate dt o safet y an dth e protectio n o

f huma n healt han d th e environment , include dsevera l EP A lists , list s develope db y othe r Federa l agencies , list s develope dunde r stat e programs , an dlist s develope dunde r internationa l programs
. Th e chemica l list s reviewe dwere :

• Th e EPCR

A (SAR A Titl e III ) Sectio n 30 2 Lis t o f Extremel y Hazardou s Substance s
• Th e EPCR

A (SAR A Titl e III) Sectio n 31 3 Lis t o f Toxi c Chemical s

• Th e Comprehensiv e Environmenta l Response , Compensation , an dLiability Ac t (CERCLA

) Sectio n 10 2 Hazardou s Substance s Lis t

• the Clean Ai r

Ac t Sectio n 112(b ) Lis t o f Hazardou s Ai r

Pollutant s

• "Th e Departmen t

o f Transportation' s (DOT ) Toxi c b y Inhalatio n List s

• OSHA' s Propose dLis t

fo r Proces s Safet y Managemen t

Regulations 1

• Tii e Ne w Jerse y Acut e Toxi c Catastroph e Lis t

1 EPA' s analysi s wa s base do n OSHA' s propose d rul e (5 5 F R29150 , July 17,1990)

. OSH A ha s sinc e publishe dafina

l standar d(5 7 F

R6356 , Februar

y 24,1992)
. • Th e Lis t fromth e Europea n Community' s (EC

) Seves o Directiv e (subsequentl y revised )

• Th e Delawar e Preventio n Regulation s Lis t

• Th e Nationa l Fir e Protectio n Association' s (NFPA) Fir e Hazar d Propertie s of

Flammabl e Liquids , Gases , an dVolatil e Solid s
• Flammabl e Gase s an dVolatil e Flammabl e Liquid s fromth e DOT Hazardou s Material s Tabl e Th e criteri ause dfo

r th e developmen t o f thes e list s wer e reviewe dt o determin e whethe r

the y wer e relate dt o th e factor s mandate db y Congres s fo r lis t developmen t

unde r CA A sectio n 112(r)

. Acut e toxicity wa s generall y considere d i n developin g thes e list s o f chemicals , bu t som e als o use dflammability an d explosivit y a s criteri afo

r regulatin g chemicals

. Severa l list s use dameasur e o f dispersibilit y (equilibriu mvapo r pressure ) i n combinatio n wit hacut e toxicity

. Furthermore , som e program s used , eithe r

exclusivel y or

i n part , criteri arathe r

tha n list s t o defin e covere dchemicals

. Th e EPCR

A (SAR A Titl e III) sectio n 30 2 list , th e DO T toxi c b y inhalatio n list , th e Ne w Jerse y acut e toxi c catastroph e list , th e Delawar e preventio n regulation s list , an dth e lis t fromth e Europea n Community' s (EC ) Seves o Directiv e ar e al l basedo n som e measure s o

f toxicit y an dth e potentia l fo r achemica l t o becom e airborne

. Th e CERCL A lis t i s no t basedsolel y o n a n airborn e criterion , bu t

rathe r i s basedo n acombinatio n of

statutor y requirement s an dcriteria

. OSHA' s lis t

i s basedo n a revie w of chemica l list s compile db y a numbe r o f Federa l an dstat e agencie s an dothe r organization s (i.e. , EPA , DOT , th e Worl dBank , NFPA , th e Healthan d Safet y Commissio n o

f th e Unite d Kingdom , an dth e state s o f Delaware an dNe w Jersey ) an di t

include s chemical s liste dfo

r toxicity an d reactivity , a s wel l a s criteri alisting s fo r flammability an dexplosivity

. NFPA' s lis t wa s develope db y committe e an d include s acompilatio n of dat afrom variou s sources
. Liste dchemical s ar e ranke daccordin g t o thei r flammability , reactivity , an dhealt hhazards ; th e flammability ranking s ar e based primaril y o n flas hpoin t

an dboilin g point

. EP A reviewe dth e DO T Hazardou s Material s Table , whic hlist s material s regulate di n transportation , t o identif y flammabl e substances

. Th e Hazardou s Material s Tabl e include s hazar dclasse s an dpackin g group s assigne daccordin g t o th e major hazard s ofth e substances

. Fo r

flammabl e liquids , packin g group s ar e assigne d primaril y b y flas hpoin t

an dboilin g point

.P. 6

Federa l Registe r

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. 58 , No

. 1 1 /

Tuesday , Januar y 19 , 199 3 / Propose dRule s 510 5
EPA' s revie w of

th e CA A sectio n 112(b ) lis t o f hazardou s ai r

pollutant s an do f th e EPCR A (SAR A Titl e III) sectio n 31 3 lis t

o f toxic chemical s indicate dtha t

bot ho f thes e list s focu s o n routin e emission s rathe r tha n accidenta l releases

. Th e CA A sectio n 112(b ) lis t i s aime dat

controllin g routin e emission s o

f hazardou s ai r pollutants ; th e EPCR

A (SAR A Titl e III) sectio n 31 3 lis t

focuse s o n al l emissions , an di s aime dat

developmen t

of informatio n o n release s t o th e environmen t

over time

. Althoug hboth o f thes e list s includ e chemical s tha t hav e advers e healt heffect s fromshort

ter mexposure , th e majority o f th e chemical s liste dhav e th e potentia l fo r producin g advers e effect s fro mlong

termexposur e rathe r

tha n short-term exposure
. Advers e healt heffect s from long-termexposur e ar e an importan t consideratio n whe n dealin g wit h routin e emissions , bu t

ar e no t th e primary concer n i n th e even t o f an accidenta l release

. Therefore , EP A determine dtha t

th e CA A sectio n 112(b ) lis t an dth e EPCR

A (SAR A Titl e III) sectio n 31 3 lis t

wer e no t o f particula r relevanc e t o th e developmen t o f th e lis t unde r CA A sectio n 112(r) , whic h focuse s o n th e preventio n o f catastrophi c accidenta l releases

. Th e factor s specifie dfo

r consideratio n i n lis t developmen t

cover abroad spectru m(se e CA

A sectio n 112(r)(4)) ; therefore , th e Agenc y se t

ou t t o defin e thes e factor s mor e specificall y i n relatio n t o accidenta l releases

. Th e Agency' s definition s ar e discusse d below

. Severity o f Acut e Advers e HealthEffects Th e severity o

f acut e advers e healt h effect s can b e relate dt o th e inheren t hazard s ofth e substance s o f interest , suc ha s th e toxicity o

f asubstanc e resultin g i n letha l effects

. Accidenta l release s woul dmos t

likel y lea dt o short

termexposur e o

f th e public , whic h coul dcaus e bot himmediat e an d delaye dtoxi c effects

. Acut e advers e healt heffect s als o coul dresul t from othe r inheren t hazards , suc ha s th e flammability o

f th e substance , or whethe r th e substanc e i s highl y reactive

. Th e phenomen aassociate d withthes e hazard s coul dbe , fo r example , radian t

hea t from achemica l fir e or blas t wave s froma n explosio n o f achemical

. A s confirme db y arevie w o f death an dinjur y events i n EPA' s Acut e Hazardou s Event s (AHE

) database , th e Emergenc y Respons e Notificatio n Syste m(ERNS ) database , th e Accidenta l Releas e Informatio n Program(ARIP ) database , an dothe r

acciden t data , th e physica l stat e (liquid , solid , gas ) an d physical/chemica l propertie s (toxicity , flammability , explosivity , an dvolatility ) o f release dsubstance s ar e importan t factor s i n th e actua l severity o f th e release

. Thes e dat asho w tha t death s an dinjurie s fromaccidenta l release s of chemical s ar e strongl y correlate dwit h thes e factors

. Becaus e physica l stat e an d physical/chemica l propertie s ar e linke d t o severity a s wel l a s likelihoo dan d potentia l magnitud e o

f huma n exposur e (discusse dbelow) , EP

A i s proposin g t o giv e thes e factor s substantia l weigh t i n selectin g it s propose dlis t o f regulate d substances

. Likelihoo do

f Releas e Ther e ar e man y measure s an d surrogate s tha t

can b e use dt o defin e th e likelihoo do

f an accidenta l release

. Th e likelihoo do

f achemica l bein g accidentall y release dcan b e relate dt o typica l usag e an dhandlin g scenarios , suc ha s equipmen t

commonl y use di n typica l facilit

y operations

. Ubiquitou s substances , becaus e o

f greater handlin g an duse , ma

y hav e agreater

potentia l fo

r a n accidenta l release

. A histor y o f a larg e numbe r

o f accident s i n th e past , fo r example , ma

y b e a n indicato r

o f an existin g hazar drelate dt o aparticula r substanc e an dit s potentia l t o b e involve di n accidenta l release s i n th e future

. Chemical s tha t

ar e foun di n larg e volume s at

man y locations an d chemical s tha t

ar e particularl y prevalen t (commodity chemicals , fo r example ) ma y b e mor e likel y t o b e involve di n accidenta l release s tha n small-volume , les s commonl y use dchemicals

. Al l o f thes e factor s ma

y b e relevan t

i n determinin g th e likelihoo do f accidenta l releas e fo r particula r

chemica l substances

. However , th e Agenc y als o believe s tha t

ther e may b e limitation s t o relianc e o n thes e factors , question s o n th e amount , validity , an dreliabilit y o f existin g acciden t

histor y data , an d question s abou t

th e practicabilit y o

f incorporatin g factor s tha t ma y var y fro m sit e t o sit e (e.g. , facilit

y operation s o

r typ e o f equipment ) i n criteri afo r a nationa l list

. Likelihoo dcan als o b e relate dt o th e possibilit y o

f th e chemica l becomin g airborn e an dhavin g an effect beyon d th e facilit y fencelin e i n th e even t

o f an accidenta l release

. Thi s likelihoo dcan b e relate dt o it s physical/chemica l properties

. Specifi c dat aindicator s can includ e physica l stat e (gas , liquid , or solid ) an dvapo r

pressure
. Althoug hi t

i s no t impossibl e fo

r solid s an dnon
volatil e liquid s t o becom e airborne i n an explosion , gaseou s substance s an d vapor s fromvolatil e liquid s ar e mor e likel y t o b e release dt o ai r an dhav e a n effec t beyon dth e facilit

y fenceline

. Becaus e th e chemica l an dphysica l propertie s of th e substance s unde r revie w ar e linke dt o bothth e likelihoo d an dth e severity o

f chemica l accidents , EP A believe s tha t

thes e tw o factor s deserv e th e greates t

weigh t i n determinin g it s propose dlis t of substances

. EP

A solicit s comment s o n othe r factor s accountin g fo

r severity an d likelihoo do

f areleas e tha t

migh t b e use dt o determin e th e lis t o f substances

. EP A als o solicit s comment s o n th e availabilit y of

dat at o suppor t

th e us e o f suc hfactors

. Magnitud e o

f Huma n Exposur e Fo r purpose s o

f today' s proposa l EP

A consider s th e magnitud e of huma n exposur e associate dwit haccidenta l release s t o b e relate dt o th e severity o f th e healt heffect s (hazards ) an dth e likelihoo do

f areleas e (th e likelihoo d tha t areleas e wil l hav e an effect o n th e populatio n or

environmen t

beyon dth e facilit y fenceline)

. Thi s definitio n o f magnitud e o

f exposur e i s somewhat different fro mth e traditiona l ris k assessmen t

definitio n o

f huma n exposure , whic hrelate s magnitud e of exposur e t o th e populatio n an d sensitiv e environment s tha t ma y b e affecte db y areleas e fro

maspecifi c site

. EP A solicit s comment s o n th e relativ e merit s o f usin g th e Agency' s approac h a s asurrogat e measur e of th e magnitud e o f huma n an denvironmenta l exposur e an drequest s commenter s t o submi t an y suggeste dmetho dfo

r determinin g magnitud e o

f huma n o r

environmenta l exposur e t o accidenta l release s o f hazardou s substances

. Th e Agenc y recognize s factor s tha t migh t affect th e magnitud e o

f huma n exposur e coul db e site-specifi c o r accident-specific , an dcoul dvary widel y b y locatio n an dincident

. Proximit y t o populatio n center s an dweathe r conditions , fo

r example , may play arol e i n th e magnitud e o

f accidenta l releases

. EP A believe s tha t

thes e an dothe r

site

specifi c factor s ar e difficul t t o us e i n determinin g nationa l criteria

. EP A solicit s comment s o n thes e an dan y othe r factor s an dan y supportin g dat a whic hma y b e usefu l i n selectin g th e lis t o f substances

. EP A ha s als o estimated , throug h analysi s o f informatio n collecte d throug hth e Accidenta l Releas e Informatio n Program(ARIP ) databas e fo

r som e o f th e liste dtoxics , th e likelihoo d tha t release s o

f thos e toxic s reporte d will resul t

i n huma n or

environmenta l impact s includin g injury , hospitalization , death , soi l contamination , vegetatio n damage , groundwate r

contamination , fire, evacuations , an dshelterin g i n place

. I n thes e events , th e actua l huma n o r environmenta l exposur e leve l i s no tP. 7

510 6 Federa l Registe r/ Vol

. 58 , No

. 1 1 /

Tuesday , Januar y 19 , 199 3 / Propose dRule s precisel y know n an di s no t predictabl e withan y degre e o

f confidenc e becaus e o f man y site-specifi c factor s tha t influenc e th e result

. However , fo r purpose s o

f thi s proposal , th e leve l o f severity or

degre e o f hazar dfo r th e particula r substanc e tha t

generate dth e off-sit e impac t i s know n suc htha t

th e severity o f th e healt heffect

an dth e likelihoo do

f releas e ha s bee n use da s a surrogat e fo

r th e actua l huma n exposur e level

. EP A request s comment s an dan y additiona l dat awhic hcoul dimprov e ou r assessmen t

o f huma n exposure
. C. Criteria Options Considered Th e CA A mandate s EP

A t o develo p a lis t o f substance s basedo n specifie d criteria , namel y severity o f advers e healt heffects , likelihoo do f accidenta l releases , an dpotentia l magnitud e o f huma n exposure
. Th e Ac t als o mandate s th e inclusio n o

f 1 6 substance s i n thi s list ; thes e substance s serv e a s th e startin g poin t

fo r th e developmen t

o f th e full lis t o f regulate dsubstances

. Th e Agenc y identifie dadditiona l substance s base do n similaritie s wit hth e mandate d substance s an dth e selectio n criteri a specifie di n th e Act

. Th e option s considere dfo

r th e selectio n criteri a accounte dfo

r th e inheren t

hazard s o

f th e substance s t o b e listed , a s wel l a s fo r th e potentia l thes e hazard s hav e t o affec t th e communit y i n cas e o f an accidenta l release

. Th e hazard s considere dinclud e toxicity , flammability , reactivity , explosivity , an dradioactivity , al l of

whic hcan resul t i n acut e effect s fromshort term exposures
. Substance s wer e identifie d fo r eac ho f thes e hazards , but , i n addition , th e Agenc y considere dth e potentia l impac t

tha t th e identifie d substance s woul dhav e o n th e communit y i n cas e o

f arelease

. Eac h hazard , an dit s potentia l t o pos e athrea t t o th e community , wa s evaluate d independentl y o

f an y othe r hazard , becaus e o f th e difficultie s o

f addressin g al l possibl e combination s o f hazards

. A grou p o f toxic substances , agrou p o f flammabl e substances , an dagrou p o f explosiv e substance s ar e bein g propose d i n today' s rul e fo

r additio n t o th e 1 6 mandate dsubstance s i n th e Act

. EP A i s proposin g t o focu s o n acut e effect s fromshort-termexposur e t o toxic s a s on e priorit y fo

r developmen t

o f thi s lis t becaus e thes e effect s ar e believe dt o b e o

f immediat e concer n beyon dth e fencelin e i n cas e of a n accidenta l release

. EP

A i s proposin g t o lis t 10 0 acutel y toxic substances

. EP A i s als o proposin g t o conside r th e physica l hazard s o f flammabl e an dexplosiv e substance s becaus e thes e effect s may hav e an impac t

o n th e communit y beyon dth e fencelin e i n th e even t o f a n accidenta l release

. Fo r flammabl e chemicals , EP

A i s focusin g o n th e effect s o f blas t wave s fromvapo r

clou d explosions , becaus e suc heffect s appea r t o hav e th e potentia l t o affect th e community beyon dth e fenceline

. A lis t o f 6 2 flammable gase s an dvolatil e flammabl e liquid s i s proposed

. EP A consider s commercia l hig hexplosives , whic hhav e th e potentia l t o detonate , t o b e th e explosiv e substance s wit hth e greates t potentia l t o affec

t th e community ; commercia l hig hexplosive s ar e propose dfo

r listin g a s acategory

. EP A als o considered , base do n analyse s o f acciden t histor y data , th e relationshi p betwee n pas t

accidenta l release s o

f toxic , flammable , an dexplosiv e substance s an dthei r

associate dhuma n an denvironmenta l effects , a s atoo l t o determin e th e likelihoo dtha t future events coul dhav e similar impacts

. EP

A seek s comment s o n thi s approach

. EP A ha s als o attempte dt o exclud e substance s fromth e lis t

tha t are no t i n productio n (or

imported ) or

tha t ar e no t handle di n commercia l quantities

. 1

. Toxicity T o accoun t

fo r th e severity o

f acut e healt heffect s fro

maccidenta l release s o

f toxi c chemicals , EP

A i s proposin g t o lis t asubse t ofth e chemical s alread y
. identiie da s EHS s o n th e basi s o f acut e toxicity (lethality ) unde r

EPCR A (SAR A Titl e lift ) sectio n 302

. For

purpose s o

f criteri afo r listing , severity o

f acut e advers e healt heffect s fro

mtoxic chemical s wa s considere dt o b e bes t measure db y th e concentratio n o r dos e leve l tha t coul dcaus e deatho

r serious , irreversibl e healt heffect s afte r ashort exposare
. Chemical s no t

o n th e EH S list , bu t liste dunde r

othe r programs , als o wer e reviewe dt o determin e whethe r ther e wer e othe r

chemical s tha t shoul db e considere dfo

r listin g o n th e basi s of th e EH S acut e toxicity criteria

. EP A believe s tha t

usin g th e EH S lis t t o identif y priorit y chemical s fo

r th e accidenta l releas e preventio n provision s i s areasonabl e approach

. Th e statut e directe dEP

A t o us e th e EH S lis t

a s a startin g poin t

fo r th e regulate d substanc e list

. Th e EH S lis t i s intende d t o identif y chemical s tha t

coul dcaus e seriou s irreversibl e healt heffect s from accidenta l release s becaus e o f thei r acut e toxicity. Th e lis t

ha s bee n revise d over th e year s base do n review s o f toxicity data

. EP

A believe s tha t

th e EH S lis t provide s an appropriat e basi s fo r identifyin g acutel y toxi c chemical s fo r th e lis t fo r accidenta l releas e prevention

. Chemical s are liste dunde r sectio n 30 2 o n th e basi s o

f anima l tes t

data , usin g th e criteri aliste dbelow

. Thes e criteri aare discusse di n mor e detai l i n Technical Guidance for

Hazards Analysis (December

1987) , aguidanc e documen t develope db y EP

A i n conjunctio n wit

hth e Federa l Emergenc y Managemen t

Agenc y (FEMA

) an dDOT

. EP A als o include do n th e EPCR A (SAR A Titl e III) sectio n 30 2 lis t chemical s tha t

ar e les s toxi c tha n thos e meetin g thes e criteri abut , becaus e o f thei r know n toxicit y an dhig h productio n volume , ma

y pos e athrea t

t o th e community

. Th e acut e toxicity criteri aare : Inhalatio n LCso£0. 5 milligram s pe r lite r o f ai r (fo r exposur e time£ 8 hours) , or Dermal LD S o£5 0 milligram s pe r kilogramo

f bod y weight , o r Oral LDJO£2 5 milligram s pe r kilogramo

f bod y weigh t wher e LCs

o i s th e media n letha l concentration , o r

th e concentratio n i n ai r at whic h5 0 percen t

ofth e tes t animal s died , an dLD J 0 i s th e media n letha l dose , o r

th e dos e tha t

kille d5 0 percen t of th e tes t animals

. I n th e absenc e o f LC 5 0 o r LD5 0 data , LCu , or LDu , dat awer e use dfo

r listing , wher e LCL O i s th e letha l concentratio n low , o r th e lowes t

concentratio n i n ai r

at whic h an y tes t animal s died , an dLDu

> i s th e letha l dos e low , o r

th e lowes t

dos e tha t kille dan y tes t

animals

. I n addition , EP

A chos e t o focu s o n physica l state , vapo r

pressure , an d acciden t histor y i n settin g criteri a relate dt o th e likelihoo do f accidenta l release s fo

r toxi c chemicals

. A vapo r pressur e criterio n o

f 0. 5 millimeter s o

f mercur y (m

mHg) unde r

ambien t condition s i s propose dfo r toxi c liquids

. Thi s criterio n capture s mos t toxi c substance s tha t

hav e relativel y lo w volatilit y bu t

may stil l pos e a n airborn e hazar di n cas e o

f an accidenta l release

. Congres s mandate dth e listin g o f toluen e diisocyanate , whic hha s a relativel y lo w ambien t

vapo r pressure ; therefore , EP

A believe s i t

i s appropriat e t o se t th e vapo r

pressur e criterio n a

t a leve l tha t woul dinclud e o n th e lis t othe r toxic liquid s wit hrelativel y lo w volatility , simila r

t o toluen e diisocyanat e tha t

als o hav e acciden t history

. Chemical s o n th e EH S lis t tha t ar e gase s unde r

ambien t condition s an d liquid s meetin g th e vapo r pressur e criterio n o

f 0. 5 m mH g wer e considere d fo r listing

. Additiona l chemical s wer e identifie do n th e basi s o

f hig h productio n volum e an dhistor y o f accident s involvin g deat hor injury

. EP A als o analyze ddat ai n th e ARI P databas e an dattempte dt o establis ha relationshi p betwee n th e presenc e o r absenc e o f acciden t preventio n measure s at

facilitie s tha t

hav e ha d significan t

accidenta l release s an dth e probabilit y tha t

th e releas e wil l result

i n

# r _u
_

Federa l Registe r

/ Vol

. 58 , No

. 1 1 /

Tuesday , Januar y 19 , 199 3 / Propose dRule s 510 7 damagin g an denvironmenta l effects

. Usin g th e ARI

P data , EP

A develope d estimate s o

f th e probabilitie s tha t release s of

thos e toxi c substance s reporte dthroug hARI

P woul dresul t

i n huma n o r environmenta l impacts

. I n thi s way , EP

A attempte dt o measur e th e potentia l magnitud e of

th e impact s resulting froman accidenta l release o f a liste dtoxi c substanc e a s i t relate s t o certai n chemica l acciden t preventio n requirements at

facilitie s tha t

handl e thes e substances

. EP

A seek s comment s o n whic htyp e o

f dat a(i.e. , relationship betwee n accidenta l releases an dhuma n an denvironmenta l impacts , acciden t history , physical/chemica l properties ) or combinatio n o

f dat acoul db e use dt o evaluat e th e magnitud e o f huma n exposur e fo

r toxics

. EP A i s focusin g o n acut e toxicit y t o identit y toxi c chemical s a s apriorit y fo r listing , becaus e acut e toxicit y i s o f th e mos t immediat e concer n i n a n accidenta l release

. However , ther e are a numbe r of othe r possibl e healt heffect s criteri atha t

migh t b e considere dat

a future tim e fo

r listin g hazardou s substances , includin g non-letha l acut e healt heffect s an dchroni c healt heffects , e.g. , lun g damage , reproductiv e an d developmenta l toxicity , an d neurologica l effects

. EP

A invite s comment s o n method s t o evaluat e substance s o n th e basi s o f thes e healt h effect s an do n ho w t o ran k substance s liste do n thes e bases

. 2

. Flammability EP A als o considere dphysica l hazard s o f chemical s i n relatio n t o acut e healt h effects

. EP

A i s currentl y reviewin g th e EPCR A (SAR A Titl e ID

) sectio n 30 2 lis t o f chemical s an dconsiderin g th e additio n o

f chemical s t o tha t

lis t based o n explosivity , flammability, an d reactivity. EP

A ha s publishe da n advanc e notic e of

propose drulemakin g (5 5 F R35012 , Augus t

27,1990 ) o n physical/chemica l propert y criteri afo r addin g chemical s t o th e sectio n 30 2 list

. Th e notic e announce dth e availabilit y of technica l backgroun ddocument s o n th e potentia l criteri afo

r listin g explosive s an dflammables

. Th e Agenc y i s proposin g substance s fo

r listin g toda y base do n th e analysi s conducte di n it s review ofth e EPCR

A (SAR A Titl e III) sectio n 30 2 list

. Th e analysi s of flammables an dexplosive s conducte d i n suppor t

of listin g unde r

sectio n 30 2 ha s bee n reviewedb y EPA' s Scienc e Advisory Board

. Result s o f additiona l analysi s tha t

may b e carrie dou t

a s a result o f tha t review i n suppor t

ofth e EPCR A (SAR A Titl e III) sectio n 30 2 lis t review wil l b e considere dprio r t o publicatio n o

f afinal rule

. EPA' s analysi s o f historica l dat ao n accidenta l release s o

f flammabl e chemical s indicat e tha t

vapo r clou d explosion s ma

y pos e th e mos t

seriou s hazar dfrom aflammabl e substanc e t o th e community

. Th e hea t effect s o f afire involvin g aflammable liqui do r gas , o r of afireball from aboilin g liquid

expandin g vapo r

explosio n (BLEVE) , d o no t hav e asever e impac t

fo r a s great a distanc e fromth e sourc e a s th e blas t effect s o f avapo r clou dexplosio n o

f th e sam e quantit y o

f aflammabl e substance

. Fo r example , a198 8 vapo r

clou d explosio n at

arefinery i n Louisiana , involvin g C 3 hydrocarbon s (primaril y propane) , cause ddamag e u p t o si x mile s away
. Base do n th e result s o f EP A modelin g o

f flammable hazard s an d analysi s o f th e literature , aclear distinctio n can b e mad e betwee n th e result s fo r flammable substance s tha t boil at temperature s belo w approximatel y 37 ° C an dhighe r boilin g flammable substances

. Analysi s o f othe r classificatio n scheme s an dregulation s indicate s tha t

flammabl e gase s an d volatil e flammabl e liquid s ar e th e flammable material s considere do f greates t concer n b y agencie s an d organization s suc ha s DOT , NFPA , an d EEC

. Th e temperatur e at

whic hclear distinction s i n consequence s can b e made , base do n modelin g techniques , correspond s t o th e temperatur e at whic h DO T an dNFP

A hav e mad e distinction s i n categorie s o

f flammable material s (boilin g poin t

belo w 38° C an dflash poin t belo w 23° C fo

r NFP A flammability ratin g 4 ; boilin g poin t belo w 35° C an dflas hpoin t belo w 23° C fo r DOT packin g grou p I)

. EP A decide d t o us e th e criteri ause db y NFP A fo r flammable gase s an dliquid s wit hth e highes t degre e o f hazar d( arankin g o

f 4 ) fo r flammability t o identif

y flammabl e substances

. Flammabl e liquid s wit ha flashpoin t

belo w 73° F(22.8°C ) an da boilin g poin t

belo w 100° F(37.8°C) , a s wel l a s flammabl e gases , are include d unde r NFPA' s highes t

flammability hazar dranking

. EP A applie dth e sam e criteri ause dfo r toxic s whe n analyzin g th e likelihoo do f releases relate dt o flammable substances

. EP

A chos e t o focu s o n physica l state , physical/chemica l properties , an dacciden t

histor y i n settin g criteri arelate dt o th e likelihoo d o f accidenta l release s o

f flammabl e substances

. Th e volatilit y of a flammabl e substanc e i s take n int o accoun t b y th e flas hpoin t

an dboilin g poin t criteria

. N o additiona l substance s wer e adde dafte

r consideratio n o

f acciden t history , becaus e th e volatilit y criterio n alread y covere dal l substance s tha t otherwis e woul dhav e bee n proposed

. EP A invite s comment s o n method s t o evaluat e substance s o n th e basi s o f thes e effect s an do n th e rankin g of thes e substances

. EP A examine dflammable s basedo n acciden t history , th e inheren t

hazard s o

f th e substances , an dth e physical / chemica l propertie s tha t

mak e the m likel y t o b e involve di n a n acciden t an d hav e a n effect

beyon dth e fenceline

. Hazar ddata , physical/chemica l propertie s data , an dacciden t histor y dat awer e use dfo

r thi s basis

. However , unlik e th e acciden t

databas e fo

r toxi c substances , EP

A doe s no t

hav e a databas e fromwhic ht o estimat e directl y arelationship betwee n th e presenc e o r absenc e o f acciden t preventio n measure s at

facilitie s wher e significan t accidenta l release s of

flammables hav e occurre dan dth e probabilit y tha t huma n o r environmenta l impact s wil l occur
. Nevertheless , historica l dat a demonstrat e tha t

flammable s can b e involve di n accident s wit hth e potentia l fo r devastatin g impact s t o th e community

. Th e Agenc y believe s tha t th e acciden t

preventio n measure s tha t hav e prove n effectiv e at

facilitie s tha t handl e toxi c substance s wil l b e a s effectiv e at

facilitie s tha t

handl e flammable substances

. EP A request s comment s an dan y dat atha t th e publi c can provid e t o directl y estimat e Ui e relationshi p betwee n th e presenc e o r absenc e o f acciden t preventio n measure s at

facilitie s wher e accidenta l release s of

thes e substance s hav e occurre dan dth e probabilit y tha t huma n an denvironmenta l impact s wil l occur
. EP A als o seek s comment s o n whic h typ e o f dat a(i.e. , relationship betwee n accidenta l release s an dhuma n an d environmenta l impacts , acciden t history , physical/chemica l properties ) o r combinatio n of

dat acoul db e use dt o evaluat e th e magnitud e o f huma n exposur e fo

r flammables

. 3

. Explosivity Explosive s ar e alread y regulatedb y severa l agencies an dorganizations

. Th e Bureau of Alcohol , Tobacco , an d Firearm s (BATF

) regulates th e manufacture , processing , use , distribution , an dstorag e o f explosiv e materials ; BATFregulation s includ e licensing , pennitting , an drecordkeeping requirement s an drequirements fo r storag e o f explosives

. DO T regulates th e transportatio n o

f explosives , an dothe r agencies suc ha s OSHA , th e Min e Safet y an dHealthAdministratio n (MSHA) , th e Departmen t

o f Defens e (DOD) , an dth e Internationa l Maritim e Organizatio n (IMO ) regulat e certai n aspect s o f th e explosive s industry

. Man y stat e an d loca l government s als o hav e regulation s regardin g licensin g an dsafet yP. 9

510 8 Federa l Registe r / Vol

. 58 , No

. 1 1 /

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r explosives

. EPA' s Acut e Hazardou s Event s databas e an d othe r dat ao n accident s sho w accident s involvin g commercia l explosiv e material s tha t

ha dan impac t

o n th e neighborin g community

. BAT F regulation s requir e tha t

explosive s b e store dat se t distance s frominhabite d buildings , highways , an drailways , limitin g th e potentia l impac t o f an accidenta l explosion

. Althoug h explosive s ar e currentl y regulate db y Federal , state , an dlocal governments , thes e regulation s d o no t

uniforml y addres s th e issu e o

f identifyin g hazard s usin g appropriat e hazar dassessmen t techniques , designin g an dmaintainin g a saf e facility , an dminimizin g th e consequence s o

f accidenta l release s whe n the y d o occur
. Al l o f thes e element s ar e t o b e addresse di n th e RM P programregulations , whic har e intende dt o hel p focu s o n acciden t prevention

. Therefore , th e Agenc y believe s thes e substance s shoul db e considere dfo

r purpose s o

f lis t developmen t

an daccidenta l releas e preventio n regulations

. Blas t wave s fromaccidenta l explosion s hav e th e potentia l t o caus e damag e t o peopl e an dpropert y beyon d th e fenceline

. EP

A considere dhig h explosives , lo w explosives , an dblastin g agent s i n it s analysi s o

f th e hazard s o

f explosives

. Hig hexplosive s ar e generall y define da s thos e material s tha t detonat e if

ignited , shocked, o r subjecte dt o hea t

o r friction. Detonation s resul t fromchemica l reactions tha t procee dat

supersoni c velocities , generatin g larg e volume s o f hig h pressur e ga s an dhea t

instantaneously , eve n thoug hn o confinin g vesse l or structur e exists

. In a n explosio n cause d b y ahig hexplosive , th e rat e of energ y releas e i s particularl y rapi dan dth e shoc k wav e ha s avery short

duratio n time

. I n contrast , lo w explosive s deflagrate , o

r bur n relativel y slowl y i n compariso n t o hig hexplosives

. A deflagratio n generate s lowe r pressure s an di s les s destructiv e tha n a detonation

. Blastin g agent s ar e relatively lo w sensitivit y explosive s whic hcanno t b e initiate db y blastin g cap s an dar e unlikel y t o explod e excep t unde r specia l conditions

. DOT define s an explosiv e a s "an y substanc e o r article , includin g adevice , whic hi s designe dt o functio n b y explosio n (i.e. , an extremel y rapi drelease o

f ga s an dheat ) or

which , b y chemica l reaction withi n itself , i s abl e t o functio n i n asimilar manne r eve n if no t designe dt o functio n b y explosio n * * * " Hig hexplosive s ar e classifie db y DO T i n Divisio n 1.1 , define da s explosive s tha t hav e amas s explosio n hazard , wher e amas s explosio n hazar di s on e tha t affect s almos t th e entir e loa dinstantaneously

. Lo w explosives , Divisio n 1. 3 unde r DOT , ar e define da s explosive s tha t hav e afire hazar dan deithe r amino r blas t hazar dor

amino r projectio n hazar dor both , bu t no t amas s explosio n hazard

. Blastin g agents , Divisio n 1.5 , ar e define da s explosive s tha t hav e amas s explosio n hazar dbu t

ar e s o insensitiv e tha t ther e i s very littl e probabilit y of initiatio n or

o f transitio n fromburnin g t o detonatio n unde r

norma l condition s o f transport

. EPA' s analysi s fo

r revisions t o th e EPCR A (SAR A Titl e ID ) sectio n 30 2 lis t indicate s tha t

blas t wave s cause db y th e detonatio n of

commercia l hig h explosive s coul dpotentiall y hav e an impac t o n th e community

. However , EPA' s analysi s indicate s tha t lo w explosives , whic hprimaril y pos e afir e hazar drathe r

tha n amas s explosio n hazard , ar e les s likel y t o caus e a catastrophi c even t

whe n compare dt o th e sam e quantit y o

f hig hexplosives

. Th e deflagratio n or

burnin g o

f alo w explosiv e generate s lowe r pressure s an d i s les s destructiv e tha n th e detonatio n of ahig hexplosives , althoug hth e Agenc y recognize s tha t

i t ma y b e possibl e fo

r som e lo w explosive s t o detonat e unde r unusua l conditions , wit heffect s similar t o th e detonatio n o

f ahig hexplosive

. Anothe r ke y distinctio n betwee n categorie s o

f explosive s i s th e likelihoo d o f initiatio n of

a n explosion

. Blastin g agents , fo r example , hav e amas s explosio n hazard , bu t

i t i s muc hmor e difficul t t o se t of f an explosio n o

f a blastin g agent , makin g the mles s likel y t o explod e accidentally

. Th e Agenc y recognizes , however , tha t i t i s stil l possibl e fo

r ablastin g agent

t o detonat e accidentall y unde r

som e circumstances

. I n thi s case , th e distinction s betwee n blastin g agent s an dhig hexplosive s may no t b e apparent ; effect s o n th e communit y coul db e felt

from explosion s o

f bot htype s o

f explosives

. EP A examine dexplosive s base do n acciden t history , th e inheren t

hazard s of th e substances , an dth e physical / chemica l propertie s tha t

make the m likel y t o b e involve di n an acciden t an d hav e a n effect

beyon dth e fenceline

. Hazarddata , physical/chemica l propertie s data , an dacciden t histor y dat awer e use dfo

r thi s basis

. However , unlik e th e acciden t

databas e fo

r toxic substances , EP

A doe s no t

hav e a databas e fromwhic ht o estimat e directl y arelationship betwee n th e presenc e o r absenc e o f acciden t preventio n measure s a

t facilitie s wher e significan t accidenta l release s o

f explosive s hav e occuia-edan dth e probabilit y tha t huma n o r environmenta l impact s wil l occur
. Nevertheless , historica l dat a demonstrat e tha t explosive s can b e involve di n accident s wit hth e potentia l fo r devastatin g impact s t o th e community

. Th e Agenc y believe s tha t th e acciden t

preventio n measure s tha t hav e prove n effectiv e at

facilitie s tha t handl e toxic substance s wil l b e a s effectiv e at

facilitie s tha t

handl e explosiv e substances

. EP

A requests comment s an dan y dat atha t th e publi c ca n provid e t o directl y estimat e th e relationship betwee n th e presenc e o r absenc e of

acciden t preventio n measure s at

facilitie s wher e accidenta l release s o f thes e substance s hav e occurre dan dth e probabilit y tha t huma n an denvironmenta l impact s wil l occur
. EP A als o invite s comment s o n method s t o evaluat e substance s o n th e basi s o f thes e effect s an do n th e rankin g o f thes e substances

. EP

A als o seek s comment s o n whic htyp e o

f dat a(i.e. , relationship betwee n accidenta l release s an dhuma n an denvironmenta l impacts , acciden t history , physical/chemica l properties ) or combinatio n of

dat acoul db e use dt o evaluat e th e magnitud e o f huma n exposur e fo

r explosives

. 4

. Reactivity I n it s analysi s fo

r EPCR A (SAR A Titl e III) sectio n 30 2 lis t

revisions , EP

A i s currentl y workin g t o identif y approache s fo

r evaluatin g th e hazard s associate dwit hothe r

type s of substance s tha t

may hav e explosiv e properties , e.g. , unstabl e substance s suc ha s certai n peroxides

. T o evaluat e th e hazard s o f

thes e substances , a numbe r o f factor s mus t

b e considered , suc ha s th e energ y o

f reaction an d whethe r aprobabl e o r

possibl e result

o f th e decompositio n o

f suc hsubstance s woul db e adeflagration , wit hhea t radiatio n th e primar y consequence , or a detonation , wit hblas t

wave s th e primar y consequence
. EP A als o ha s examine dth e chemical s tha t ar e highl y reactive wit hai r

o r water ; identifyin g commo n characteristic s or specifi c propertie s tha t

caus e chemical s t o b e s o reactive wit hai r

o r wate r a s t o pos e a hazar dt o th e communit y requires additiona l study

. Fo r

example , chemical s tha t

ar e reactiv e wit hwate r may reac t t o produc e aflammabl e gas , creatin g afire or

explosio n hazard , or

t o produc e atoxi c gas , o r

the y may decompos e explosivel y o n contac t wit h water ; th e consequence s of thes e reaction s woul db e very different

. A t present , EP

A i s attemptin g t o evaluat e th e hazard s o f

reactiv e chemical s an dt o develo p a n adequat e technica l basi s t o determin e th e potentia l effect s o n th e community

. EP

A i s investigating , fo

r example , compute r

model s tha t

estimat e heat s o f reaction, an dth e possibl e us e ofth e heat s o

f reaction t o compar e th eP.1 0



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Tuesday , January 19 , 199 3 / Propose dRule s 510 9

effect s o f a n explosio n o f

a n unstabl e substanc e t o th e effect s o f a n explosio n o f trinitrotoluen e (TNT)

. Thi s methodolog y woul donl y b e appropriat e fo r substance s tha t

detonate , whic h appear s t o b e unlikel y fo r man y unstabl e substances

. Unstabl e an d reactiv e substance s wil l b e considere d fo r listin g fo r

accidenta l releas e preventio n i f

th e evaluatio n indicate s potentia l consequence s involvin g th e community

. Thus , an y decisio n relatin g t o thi s typ e o f

hazar dwil l b e deferre d pendin g additiona l Agenc y review

. EP A request s comment s o n method s tha t migh t b e use dt o evaluat e th e potentia l consequence s o f

accident s involvin g reactiv e substances

. 5

. Radioactivit y EP A i s requestin g informatio n t o determin e th e nee dan dappropriatenes s o f listin g radionuclide s unde r thi s propose drulemaking

. Ther e ar e severa l issue s tha t

th e Agenc y consider s o f importanc e i n makin g suc ha determination

. D o an y o r al l radionuclide s a t

facilitie s no t

license d b y th e Nuclea r

Regulator y Commissio n (NRC ) pos e risk s o f

sever e healt heffect s i n cas e o f

a n accidenta l release ? If som e radionuclide s wer e listed , shoul dthe y b e liste daclas s o f

substances , o r

i s i t mor e appropriat e t o prioritiz e thei r hazard s an dlis t

specifi c radionuclide s o f concern ? Wha t

specifi c approache s coul db e take n t o develo p a methodolog y tha t

set s threshold s fo r radionuclide s tha t

woul drepresen t equivalen t

hazard s t o thos e pose db y othe r substance s liste dunde r thi s rule ? I s th e volatilit y o f

radionuclide s relevan t t o thei r potentia l t o b e released ? Th e Agenc y i s intereste di n obtainin g informatio n o n th e univers e o f facilitie s potentiall y affecte db y listin g radionuclides ; th e baselin e considere d b y th e Agenc y i s listin g o f radionuclide s a s aclas s wit hlevel s simila r t o thos e establishe dfo r

NRC-license dfacilitie s unde r NURE G1140 , A Regulator y Analysi s o n Emergenc y Preparednes s fo r Fue l Cycl e an dOthe r

Radioactiv e Material s Licensee s (NRC-license d facilitie s ar e exemp t

fromthes e provision s unde r

th e CA A amendments)

. Finally , th e Agenc y request s comment s o n ho w regulation s tha t ma y b e i n plac e fo r

th e accidenta l releas e preventio n o f

radionuclide s a t th e Federal , state , o r

loca l level s woul d interac t wit hth e acciden t

preventio n requirement s applicabl e t o thes e substances

. D. List of Substances 1

. Propose dLis t EP A i s proposin g alis t o f 10 0 toxi c chemical s base do n th e criteri a discusse dabov e an dth e lis t o f chemical s mandate dfo r inclusion

. EP A i s als o proposin g alis t

o f 6 2 flammable gase s an dvolatil e flammable liquids

. Th e list s o f

toxi c an dflammabl e chemical s ar e se t

fort hi n §67.13 0 ofth e propose drule

. EP A i s als o proposin g th e commercia l explosive s i n Divisio n 1. 1 (explosive s wit hamas s explosio n hazard) , a s define db y DOT ; individua l commercia l explosive s ar e no t include d o n th e propose dlist

. I n proposin g thi s list , EP A considere dth e factor s specifie di n th e Act : severit y o f acut e advers e healt heffect s associate dwit h accidenta l releases , th e likelihoo do f accidenta l releases , an dth e potentia l magnitud e o f

huma n exposur e t o accidenta l release s (albei t no t directl y a s functio n o f

factor s suc ha s populatio n exposed)

. A s note dabove , eac hhazar d wa s evaluate dindependently

. Th e final lis t adopte db y th e Agenc y ma y consis t o f acombinatio n o f

an y o f thes e substances

. Substance s wil l b e place d o n th e fina l lis t

accordin g th e statutor y criteri aan dbase dupo n publi c commen t an dadditiona l informatio n provide db y th e publi c o r

develope db y th e Agenc y a s aresul t

o f publi c comment

. a. Toxic Substances. Al l o f th e 9 3 EHS s o n th e lis t

o f 10 0 toxi c chemical s propose dfo r

listin g ar e reporte dt o b e toxi c b y inhalation ; inhalatio n toxicit y woul db e expecte dt o b e th e greates t hazar dt o th e publi c fro ma n accidenta l releas e t o air

. Th e lis t

include s th e followin g categorie s of

chemicals : o Gases on the EHS

list. Th e lis t include s 2 2 gase s tha t

mee t th e toxicit y criteri abase do n thei r

presenc e o n th e EH S lis t an dmee t

th e criteri afo r likelihoo do f

accidenta l release s base d o n thei r physica l stat e an dth e fac t tha t the y ar e i n commercia l production

. Tw o othe r gase s meetin g thes e criteria , ozon e an dnitroge n dioxide , hav e primar y nationa l ambien t

ai r qualit y standard s an dare , therefore , exclude dfro mth e lis t b y statute

. o Liquids on the EHS

list with vapor pressure of

0.5mm Hg or

greater. Ther e ar e 6 5 liquid s tha t

mee t th e toxicit y criteri ab y virtu e o f

inclusio n o n th e EH S lis t an dmee t

th e criteri afo r likelihoo do f

accidenta l release s becaus e thei r vapo r pressur e unde r

ambien t condition s i s 0. 5 m mH g o r higher , an d the y ar e i n commercia l production

. Tw o additiona l chemical s meetin g thes e criteria , methy l viny l keton e an d methacryloy l chloride , wer e no t include dbecaus e th e toxicit y dat ause d fo r listin g ar e base do n inhalatio n studie s tha t ma y contai n flawe d scientifi c methods

. EP A requeste d comment s o n thes e tw o chemical s i n a propose drul e t o delet e severa l chemical s fromth e EH S list

. N o comment s wer e received , an dn o additiona l toxicit y dat awer e obtained ; therefore , thes e chemical s wer e no t delete dfromth e EH S list

. However , EP A doe s no t

believ e i t

i s appropriat e t o includ e methy l viny l keton e an d methacryloy l chlorid e o n thi s propose d lis t base do n toxicit y dat atha t ma y b e questionable

. o Other liquids on the EHS

list. Toluen e 2,4-diisocyanat e (584-84-9 ) an dtoluen e 2,6-diisocyanat e (91-08-7 ) ar e include do n th e lis t becaus e Congres s mandate dth e listin g o f toluen e diisocyanate

. Fou r liquid s from th e EH S lis t

ar e include dbecaus e the y ar e produce di n hig hvolume s an dhav e bee n involve di n anumbe r o f accident s i n th e pas t

i n whic hdeath s o r

injurie s hav e occurred , base do n informatio n fromsevera l databases , includin g th e AHE , ERNS , an dARI P databases ; therefore , the y mee t

th e likelihoo d criteria , althoug hthe y hav e ambien t vapo r pressure s les s tha n 0. 5 m mHg , Thes e chemical s (CA S number s i n parentheses ) are : nitrobenzen e (98-95

- 3) , parathio n (56-38-2) , pheno l (108

- 95-2) , an dsulfuri c aci d(7664-93-9)

. (EP A i s proposin g t o includ e pheno l i n liqui dfor monly ; pheno l i s alow

meltin g soli dunde r

ambien t condition s bu t i s frequently store dan dshippe da s aliqui dabov e it s meltin g point. ) Th e acciden t histor y dat aan dhig h productio n volum e indicat e tha t thes e substance s pos e agrea t ris k t o huma n healt han dth e environmen t from accidenta l releases

. Release s t o ai r

ar e reporte dfo r

al l o f thes e substance s i n EPA' s AH E database , eve n thoug hthei r vapo r pressur e i s les s tha n 0. 5 m mHg

. Sulfuri c aci di s on e o f

th e mos t frequentl y reporte dchemical s involve d i n incident s wit hdeat han dinjur y i n EPA' s AH E database , an dth e mos t frequentl y reporte di n al l accidents ; i n addition , i t

i s th e highest-volum e chemica l i n commerc e i n th e U.S

. Th e AH E databas e include s nearl y 20 0 report s o f

incident s involvin g sulfuri c acid , mor e tha n hal f

o f the minvolvin g release s t o ai r

an d6 0 o f

the minvolvin g death s o r

injuries

. Ai r

release s wer e reporte di n mor e tha n hal f o f th e incident s wit hdeath s o r injuries , includin g fou r

wher e explosion s wer e reported

. Th e ARI P databas e include s nearl y 15 0 report s fo r

sulfuri c acid

. Migratio n o f

sulfuri c aci dbeyon dth e facilit y boundarie s wa s reporte di n a significan t

numbe r (32 ) o f incidents

. I nP.1 1

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tw o o f thes e cases , migratio n o

f sulfuri c aci da s avapo r

o r ga s wa s reported

. Fo r phenol , th e AH

E databas e include s report s o

f 2 4 incidents , wit h one-thir do

f the minvolvin g releases t o air

. Death s or

injurie s wer e reportedi n five pheno l incidents , wit hai r release s reporte di n tw o o

f them

. Th e ARI

P databas e include s 1 0 report s fo r phenol , withmigratio n beyon dth e fencelin e reporte di n four

of them

. I n tw o of

thes e cases , migratio n beyon dth e fencelin e wa s reporte dfo

r pheno l vapor
. Parathio n incident s wer e reported1 1 time s i n th e AH

E database , wit hrelease s t o ai r reporte di n mos t

o f them , an d death s or injurie s reporte di n eigh t o f them

. Recent

regulation s hav e restricte d th e us e o f parathion ; a s aresul t

o f th e restrictions , th e likelihoo do f accident s involvin g parathio n may decrease

. EP A request s comment s o n whethe r parathio n shoul db e include do n th e lis t o f regulate dsubstance s or

whethe r curren t regulation s ar e sufficient t o preven t accident s involvin g parathion

. Fo r nitrobenzene , ther e wer e fou r incident s reporte di n th e AH E database , al l wit hrelease s t o air

. Tw o ofth e incident s involve ddeath s o r injuries , withalarg e numbe r

o f death s reporte d i n on e incident , i n whic ha n explosio n an dfir e wer e reported

. • Non-EHSs. Tw o gase s propose dfo r listing , methy l chlorid e (74-87-3 ) an d viny l chlorid e (75-01—4) , ar e no t o n th e EH S lis t bu t ar e mandate dfo

r listing

. Bot ho f thes e chemical s hav e ahistor y o f accident s involvin g deathor injury

. Bot ho f thes e chemical s are als o highl y flammabl e an dwoul dmee t th e listin g criteri afo r flammability

. N o othe r

gases , chlorin e dioxid e (10049-04-4 ) an d cyanoge n chlorid e (506-77—4) , wer e recommende dfo

r listin g b y OSHA , an d are include dbecaus e o

f thei r toxicity , potentia l fo

r airborne release , an d productio n volume

. Chlorin e dioxid e appear s t o mee t

th e criteri afo

r "other " chemical s o n th e EH S list , base do n toxicity an dproductio n volume

. Cyanogen chlorid e doe s no t strictl y mee t th e listin g criteria , primaril y becaus e th e availabl e dat aar e fo r extremel y short

exposur e periods ; however , dat aindicat e tha t thi s substanc e i s highl y toxi c an dwoul d probabl y mee t

th e EH S criteri aif adjustment s wer e mad e fo r duratio n o

f exposure
. EP

A conclude dtha t

listin g i s appropriate , basedo n availabl e data

. Congres s mandate dth e listin g o f bot h anhydrou s ammoniaan dammonia ; th e EH S lis t include s onl y on e listin g fo r ammonia , wit hn o for

mspecified

. EP

A i s proposin g t o includ e bot hammoni a (anhydrous ) (7664-41-7 ) an d ammonia—aqueou s (solution s wit htota l ammoni aconcentratio n i n wate r o f 2 0 percen t

b y weigh t

o r greater)

. Th e concentratio n cut-of

f wa s chose n s o tha t commonl y use dcommercia l solution s o f ammeni awoul db e covered

. Coagres s als o mandate dth e listin g o f toluen e diisocyanate , withou t specifyin g a n isomer ; EP

A i s proposin g t o lis t toluea e diisocyanat e (unspecifie d isomer ) (26471-62-5) , whic hi s no t o n th e EH S list , i n additio n t o toluen e 2,4

- diisoeyanat e (584-84-9 ) an dtoluen e 2,6-dIsocyanat e (91-08-7) , whic har e EHSs , Th e TSC

A Inventory include s thes e thre e listing s fo

r toluen e diisocyanat e (an dn o othe r listings)

. Includin g unspecifie disomer s o n Ui e lis t shoul dhel p t o ensur e tha t al l form s o f toluen e diisocyanat e ar e covered , i n conformanc e wit hUi

e inten t o f Congsess

. Hydrochlori c aci d(solution , concentratio n 2 5 percen t

b y weigh t

or greater) (7647-01-0) , whic hi s no t an EHS , i s propose dfo

r listing , i n additio n t o anhydrou s hydroge n chloride , whic h i s an EHS

. Th e concentratio n cut-of f o f 2 5 percen t

i s intende dt o cover commonly-use dcommercia l solution s o f hydrochlori c acid ; solution s o f hydrochlori c aci di n thes e concentration s coul dreleas e hydroge n chlorid e ga s i n th e even t

o f aspill

. Listin g o f th e solutio n i s propose do n th e basi s o

f it s potentia l t o releas e hydroge n chloride , hig hvolum e use , an dacciden t

history. Hydrochlori c aci d i s on e o f th e mos t frequently reporte d chemical s i n deathan dinjur y events an di n al l events i n th e AH E database ; th e ARI P databas e als o include s man y report s o f incident s involvin g hydrochlori c acid

. b

. Flammable Substances. Th e propose dlis t

o f 6 2 flammabl e substance s include s 4 3 flammabl e gase s an d1 9 volatil e flammable liquid s tha t mee t th e criteri afo

r NFPA' s highes t flammability hazar dranking

. Thes e substance s wer e identifie dfro mNFPA' s Propertie s o

f Flammabl e Liquids , Gase s an dVolatil e Solid s an dDOT' s Hazardou s Material s Table ; i n addition , ther e wa s evidenc e o

f productio n o

f thes e substance s i n commercia l quantities

. EP

A i s no t proposin g t o cover an y o f thes e substance s whe n the y ar e use dsolel y fo

r facilit y consumptio n a s fuel

. Tw o additiona l chemical s tha t met th e criteri afo

r listin g wer e exclude dfromth e lis t

becaus e the y ar e covere dunde r

titl e V I o f th e Ac t a s amended

. Som e ofth e substance s liste d o n th e basi s o

f toxicity als o mee t

th e flammability criteria ; the y are liste da s toxi c substances , however , an dwer e no t considere dfo

r listin g a s flammables.
c
. Explosive Substances. EP A i s proposin g t o includ e al l explosive s tha t mee t th e criteri aspecifie db y DOT fo r Divisio n 1. 1 (5 5 F

R52402 , December 21,1990 ; 4 9 CF

Rpart 172) , whic har e base do n th e Unite dNation s Recommendation s o n th e Transpor t o f Dangerou s Goods

. Hig hexplosive s ar e propose dfo

r listin g a s aclass , rathe r tha n a s individua l substances , becaus e explosive s ar e usuall y mixture s o r formulation s rathe r

tha n specifi c chemicals

. An individua l chemica l coul db e acomponen t

of ahig h explosiv e o r

alo w explosive , o r

coul d b e non-explosive , dependin g o n variou s factors ; e.g. , particl e size , concentration , an dothe r component s o

f th e fonnulation

. EP

A i s no t proposin g t o lis t an y individua l explosiv e substances

. a. Toxic Substances Not

Proposed

for Listing. Severa l toxic substance s tha t initiall y appeare dt o mee t th e listin g criteri aar e no t

propose dfo

r listin g at thi s time

. Thes e substance s includ e tw o tha t wer e liste da s EHS s o n Ui e basi s o f toxicity dat abase do n inhalatio n studie s tha t ma y contai n flawedscientifi c methods

. Thes e tw o substances , methy l viny l keton e (78-94-4 ) an d methacryloy l chlorid e (920-46-7) , ar e no t propose dfo

r listin g toda y becaus e o

f th e questionabl e natur e o f th e toxicity data

. Tw o additiona l substance s o n th e EH S lis t Uia t di dno t mee t th e vapo r pressur e criterio n wer e considere dfo r listin g becaus e the y hav e bee n involve d i n anumbe r

o f accident s wit hdeatho r injury

. Thes e substances , chlordan e (57-74-9 ) an dtetraethyllea d(78-00-2) , ar e no t propose dfo

r listin g becaus e recen t regulatory development s make i t unlikel y tha t

the y wil l b e produce di n commercia l quantitie s i n th e future ; therefore , the y ar e unlikel y t o b e involve di n potentiall y catastrophi c accidents

. EP

A requests comment s o n th e exclusio n o

f thes e chemical s from th e propose dlis t

o f substances

. 2

. Othe r Lis t Option s A s discusse dabove , th e Agenc y i s proposin g alis t

o f substance s comprise d o f thre e distinc t

categories : toxics , flammables , an dexplosives

. Th e substance s liste dunde r

eac hcategor

y confor mt o th e discusse dcriteri afo r th e particula r hazar di t presents , an dreflect ameasur e o

f likelihoo do

f off-sit e impact s i n cas e o

f accidenta l release. Becaus e thes e categorie s hav e bee n develope dindependentl y o f eac hother , th e Agenc y may choose , at Ui e tim e o f final promulgation , t o adop t an y o f thes e hazar doptions , o r

an y individua l substanc e covere db y thes e option s basedo n publi c commen t an dan y additiona l informatio n provide do r develope db y th e Agenc y a s aresult of publi c comment

. In additio n t o thos e option s tha t woul db e variation s of

th e propose dlis tP.1 2

Federa l Registe r

/ Vol

. 58 , No

. 1 1 /

Tuesday , Januar y 19 , 199 3 / Propose dRule s 511 1

o f substance s (e.g. , toxic s only ; toxic s an dflammable s only ; asubse t includin g toxics , flammable s an dexplosives) , th e Agenc y als o considere da n additiona l optio n fo r th e lis t o f regulate d substance s tha t

woul dmee t

th e statutory criteria

. Thi s optio n i s discusse dbelow

. Th e Agenc y request s comment s o n an y variatio n o f th e propose dlist , a s wel l a s o n th e additiona l optio n fo

r comment

. Entire EHS

List. EP A considere dUi

e optio n o f adoptin g Ui

e entir e lis t

of 36 0 chemical s regulate dunde r EPCR A (SAR A Titl e III) sectio n 30 2 a s th e lis t o f toxi c chemicals

. Thes e chemical s ar e liste do n th e basi s o

f acut e toxicity , and , therefore , mee t

th e criterio n o

f severity o f acut e healt heffects

. Sinc e thi s lis t wa s adopte di n 1986 , toxicity dat afo r man y o f th e chemical s hav e bee n reviewe do r

are currentl y unde r

review , dat ao n othe r

propertie s hav e bee n collecte dan dupdated , an dothe r chemical s hav e bee n reviewe dfo r possibl e additio n t o th e list

. However , Ui e EH S lis t i s basedsolel y upo n acut e toxicity fo

r mos t o f th e substances , withou t an y consideratio n o

f thei r volatility , whic hrelate s t o th e likelihoo do

f tha t substanc e bein g involve di n acatastrophi c airborn e accidenta l releas e tha t

carrie s beyon d th e facilit y fenceline

. Fo r

th e initia l lis t o f substance s fo

r accidenta l releas e prevention , EP

A propose s t o focu s o n thos e toxic chemical s posin g th e greates t potentia l threa t

t o Uie communit y fromairborn e releases

. In thi s way , th e initia l list-wil l reflec t th e statutory criteri ao

f likelihoo dan d magnitud e o

f release

. Th e EH S lis t include s anumbe r

o f solid s an dnon
volatil e liquid s Uiat , althoug hthe y mee t th e toxicity criteria , ar e expecte dt o b e muc hles s likel y t o hav e a n effect beyon dUi

e fencelin e i n Ui

e even t o f an accidenta l releas e tha n thos e EHS s Uia t are gase s an dvolatil e liquids

. E. Threshold

Quantities Unde r CA A sectio n 112(r)(5) , EP

A mus t establis hthreshol dquantitie s fo r eac hsubstanc e at

th e tim e of

listing

. Th e threshol dquantit y shoul dtak e int o accoun t th e toxicity , reactivity , volatility , dispersibility , combustibility , o r flammability o

f Ui e substance , an d th e amoun t

o f th e substanc e know n or anticipate dt o caus e death , injury , o r seriou s advers e huma n healt heffects

. Substance s use db y farmer s a s agricultura l nutrient s may b e assigne d greater threshol dquantitie s o r exempted

. Two issue s relatedt o threshol dquantitie s wer e considered : Developmen t

of a n appropriat e threshol dquantit y fo

r triggerin g th e ris k managemen t

preventio n regulation s an d developmen t o f ametho dfo

r determinin g whethe r

astationary sourc e ha s presen t

aquantit y o

f aliste d chemica l greate r

tha n th e threshol d quantity

. Th e Agenc y doe s no t conside r an y threshold s t o b e aprecis e measur e ofa"safe " level ; n o suc hleve l can b e determined

. Th e ris k

pose db y an y chemica l releas e depend s o n th e particula r circumstance s at

th e tim e o

f th e release ; fo

r example , release s o

f th e sam e quantit y o

f Ui e chemica l ma

y pos e ver y different

threat s dependin g o n th e locatio n o f afacility , weathe r

a t Ui e tim e o f th e release , th e elevatio n o f th e sourc e o f th e releas e (e.g. , areleas e from asmokestac k

versu s agroun dleve l release) , an dth e pressur e an d temperatur e o

f th e substance , amon g othe r factors

. 1

. Revie w o

f Threshol dMethodologie s In developin g threshol dquantities , th e reportin g threshold s associate dwit h Ui e othe r list s considere dan dth e method s use dt o develo p the mwer e reviewed

. Thi s revie w i s discusse d below

. Delaware Methodology. Th e Delaware threshold s fo

r toxic chemical s wer e determine do n th e basi s o f dispersio n modelin g an dacombinatio n o f toxicit y an dvapo r pressure ; th e Delaware "Sufficien t

Quantity " (SQ) fo

r atoxic chemica l i s define da s th e quantit y tha t woul dcreat e apotentiall y letha l concentratio n at

th e facilit y boundar y i

f releasedover

aperio do

f on e hour

. Th e threshold s ar e calculate dbase do n an assumptio n o

f a100-meter

distanc e t o Ui e fenceline

. I

f th e distanc e at

afacilit y i s greater , th e threshol di s adjuste d upward

. Fo r flammable materials , Delaware provide s acalculatio n metho dfo r determinatio n o

f th e S Q base do n a compariso n wit hpropane
. Th e Delawar e calculatio n i s base do n th e release rat e calculate dfo

r propan e a s sufficient t o caus e deathor

permanen t disabilit y fromhea t

radiatio n resultin g fromafireball at

adistanc e o

f 10 0 meter s fromth e poin t

o f release

. SQ s fo

r othe r flammable substance s ar e calculate dbasedo n Ui

e propertie s o

f Ui e substance s compare dt o th e propertie s o f propane
. Threshold s can b e adjuste d upwar dfo

r fencelin e distance s greate r tha n 10 0 meters , a s fo

r toxics i Delaware specificall y exclude s commercia l explosive s fromit s list

. Fo r potentiall y explosiv e chemical s tha t ar e no t commercia l explosives , SQ s ar e determine db y relating explosio n energ y fo r agive n mas s o

f materia l t o an equivalen t

mas s o f TNT

. Th e scalin g law , whic hrelate s blas t

overpressure , distance , an dmas s o

f TNT , wa s use dt o calculat e SQs

. Th e S Q fo

r areactiv e substanc e wa s th e quantit y calculate dt o

creat e an overpressur e o

f 2. 3 pound s pe r squar e inc h(psi ) at

adistanc e o

f 10 0 meters

. New Jersey Methodology. Ne w Jerse y threshold s fo

r toxi c chemical s ar e se t base do n dispersio n modelin g an d mortalit y curves ; aRegistratio n Quantit y (RQ ) i s th e quantit y Uia

t wil l produc e on e fatalit y i n alocatio n wit h10,00 0 peopl e pe r

squar e mile

. Ne w Jerse y doe s no t currentl y lis t

flammabl e o r explosiv e substances

. ORC Methodology. Th e methodolog y recommende db y th e Organizatio n Resource s Counselor s (ORC) fo r th e developmen t

o f threshol dquantitie s fo

r toxic chemicals , presente db y OR C t o OSHA i n publi c hearings , wa s als o reviewed

. Thi s metho duse s dispersio n modeling , assumin g th e tota l quantit y o f th e substanc e release dimmediatel y become s airborne , t o determin e Ui e quantit y o

f atoxi c substanc e Uia

t woul d lea dt o aconcentratio n tha t coul dcaus e deatho r permanen t

disabilit y at

a distanc e o

f 10 0 meter s fromth e poin t o f releas e from aone-hou r

exposure
. Fo r reactiv e chemicals , tn e threshol d methodolog y recommende db y OR C wa s th e sam e a s tha t

use db y Delawar e t o develo p SQ s fo

r explosiv e chemicals , describe dabove

. EHS TPO Methodology. Th e threshol d plannin g quantitie s (TPQs ) develope d fo r EHS s ar e base do n arankin g o f th e EHS s accordin g t o thei r

potentia l t o becom e airborne , dispersio n potenUal , an dtoxicologica l properties , wit h adjustment s base do n chemica l reactivit y an dothe r

factors

. T o develo p th e TPQ s fo

r EHSs , th e Immediatel y Dangerou s t o Lif

e an dHealth(IDLH

) leve l develope db y th e Nationa l Institut e of

Occupationa l Safet

y an d Health(NIOSH) , or

a n approximatio n o

f Ui e IDL H base do n anima l toxicit y data , wa s use da s a n inde x of

toxicity

. Physica l stat e an dvolatilit y wer e use d t o deriv e a n inde x o

f th e chemical' s potentia l t b becom e airborn e an d disperse

. Th e tw o indice s wer e combine dt o produc e a n overal l ris k "rankin g factor " define da s IDLH/V , wher e V i s th e inde x o

f potentia l t o becom e airborn e an ddisperse

. TPQ s wer e assigne dt o group s o f EHS s accordin g t o thei r

relative ranking

. Th e inde x o

f potentia l t o becom e airborn e an ddispers e (V

) wa s derive d base do n physica l stat e an dvolatility

. Fo r EHS s tha t

ar e gase s unde r

ambien t conditions , V wa s assume dt o hav e a valu e of 1 , indicatin g tha t

i n a n accidenta l release , th e tota l quantit y o f chemica l involve di n Ui

e releas e coul d becom e airborne

. Fo r

liquids , V wa s calculate db y estimatin g th e rat e o f volatilizatio n from apoo l (assume dt oP.1 3



### 511 2 Federa l Registe r/ Vol

. 58 , No

. 1 1 /

Tuesday , Januar y 19 , 199 3 / Propose dRule s
b e on e centimete r

i n depth ) o n aflat , non-absorbin g surfac e usin g equation s presente di n Attachmen t

1 o f th e Interi mFina l Rul e o

f November

17 , 1986 , listin g EHS s unde r

EPCR A (SAR A Titl e III) sectio n 30 2 (5 1 F R41580)

. Liquid s wer e assume dt o b e at thei r boilin g point , an dal l liquid s wer e assume dt o hav e th e sam e densit y a s water

. A mas s transfe r

coefficient

wa s estimate db y referenc e t o water

. Becaus e o f thes e assumptions , th e onl y variable s use di n th e calculatio n o

f V wer e th e molecular weigh t an dboilin g poin t

o f th e liquid

. Th e EHS s wer e ranke daccordin g t o th e rankin g factor

IDLH/ V an dassigne d TPQ s o f 1,10,100 , 500,1,000 , or 10,00 0 pound s base do n orde r

o f magnitud e range s i n th e rankin g factor

. Th e TPQ s assigne dbasedo n th e rankin g factor s wer e reviewed , an dchange s wer e mad e base do n othe r

toxicit y data , rapi d absorption , chemica l reactivity , an d consideratio n o

f specifi c handling , formulation , an dus e information

. 2

. Propose dThreshol dMethodolog y Relative Ranking for

Toxic Chemicals. T o se t threshold s fo

r toxic chemicals , EP A i s proposin g t o us e arankin g metho dsimilar

t o tha t use di n developin g th e TPQ s fo

r EHSs , a s describe dabove , modifie dt o reflec t th e different purpose s o

f threshold s unde r thi s rulemaking ; i.e. , unde r EPCR A (SAR A Titl e III) sectio n 302 , threshold s onl y trigger

reportin g b y facilitie s t o stat e an dloca l planners , whil e unde r CA A sectio n 112 , facilitie s wit hliste d substance s i n quantitie s exceedin g th e threshol dwil l b e require dt o compl y withpreventio n requirements , suc ha s th e developmen t

o f ris k managemen t plans

. Usin g th e revise dthreshol d methodology , arankin g facto r basedo n toxicity an dpotentia l t o becom e airborn e an ddispers e wa s derive da s describe dabove

. I n some cases , revise d toxicity dat aor

IDL H value s wer e used

. Threshold s wer e assigne db y orde r o f magnitud e range s i n th e rankin g factor ; threshol dquantit y categorie s ar e a s follows : 50 0 pounds , 1,00 0 pounds , 5,00 0 pounds , an d10,00 0 pounds

. Th e threshol dquantitie s selecte dare , at th e minimu mleve l of

50 0 pounds , representativ e o

f drum-siz e containers , and , at th e maximu mleve l o

f 10,00 0 pounds , consisten t

wit hreportin g requirement s alread y i n plac e fo r EPCR A (SAR A Titl e IH ) unde r section s 311-31 2 an d302

. Unde r

EPCR A (SAR A Titl e III) section s 311-312 , facilitie s mus t submi t materia l safet

y dat asheets , chemica l lists , or

inventor y reports o n hazardou s chemical s t o stat e an dlocal agencie s at

athreshol dfo

r mos t chemical s o

f 10,00 0 pounds

. Unde r EPCR A (SAR A Titl e ffl) sectio n 302 , Ui e maximu mTP Q fo

r EHS s i s 10,00 0 pounds ; th e presenc e o

f aTP Q o f a n EH S require s facilitie s t o notif y stat e an dlocal planners

. A relativ e rankin g metho dt o assig n threshold s ha s advantage s ove r developin g substance-specifi c threshold s basedo n dispersio n modelin g becaus e airborn e dispersio n mode&ng involve s man y site-specifi c an daccident-specifi c parameters , includin g Ui

e distanc e fromth e sourc e t o th e communit y or

fenceline , th e condition s unde r

whic hth e chemica l i s handle d(e.g. , temperatur e an d pressure) , th e topograph y ofth e are a aroun dth e facility , an dmeteorologica l condition s at

th e tim e of

Ui e release

. Th e Agency' s analysi s showe dtha t assumption s mad e fo

r modelin g caus e wid e variation s i n th e results

. In additien , th e relativ e rankin g take s int o accoun t bothtoxicity an dvolatility

. Ai r dispersio n modelin g alon e doe s no t take int o accoun t

Ui e potentia l fo

r a substanc e t o becom e airborne

. Thi s relativ e rankin g metho dals o i s consisten t wit hUi e methodolog y fo

r assignin g TPQ s unde r

EPCR A (SAR A Titl e III) sectio n 302

. Thi s methodolog y ha s bee n appUe dt o develo p threshold s fo

r additiona l substance s tha t

woul db e liste dif

EP A chos e th e option , discusse dabove , o f adoptin g Ui

e entir e lis t

of EHS s regulate dunde r

EPCR A (SAR A Titl e III) sectio n 302

. Refe

r t o Ui e technica l backgroun ddocument s i n th e docke t fo r mor e mformatio n o n threshold s fo r EHS s so t propose dfo

r listing

. Threshold s hav e bee n develope dusin g thi s methodolog y fo

r Ui e fou r toxic chemical s discusse dpreviously , tha t appeare dt o mee t

th e listin g criteri abu t hav e no t bee n propose dfo

r listin g becaus e o f questionabl e toxicity dat ao r becaus e the y ar e no t

expecte dt o b e produce di n commercia l quantitie s i n th e future

. Th e threshold s fo r thes e chemical s woul dbe : chlordan e (57-74

- 9) , 5,00 0 pounds ; methacryloy l chlorid e (920-46-7) , 50 0 pounds ; methy l viny l keton e (78-94-4) , 50 0 pounds ; tetrae&yllea d(78-00-2) , 1,00 0 pounds

. Threshold Methodology for Flammable Substances. EPA' s analysi s ofth e hazard s o

f flammabl e chemical s indicate s tha t

th e greates t

hazar dt o th e publi c fromthes e substance s i s from vapo r clou dexplosions

. Historica l dat a indicat e tha t

vapo r clou dexplosion s ar e unlikel y fo

r vapo r cloud s containin g quantitie s les s tha n 10,00 0 pounds

. Th e quantit y i n avapo r

clou dresulting from a n accidenta l releas e o

f aflammable ga s or volatil e flammable liqui dcoul dvary greatl y dependin g o n site-specifi c an d accident-specifi c conditions , a s wel l a s propertie s of th e chemica l released

. Becaus e i t

woul db e difficul t

t o se t chemical-specifi c threshold s base do n al l thes e factors , EP

A i s proposin g t o se t Ui e threshold s fo

r al l th e liste d flammabl e substance s at

10,00 0 pounds

. EP A believe s tha t

thi s threshol di s conservativ e an dprotectiv e of Ui e publi c becaus e Ui

e vapo r clou dresultin g fromarelease o

f 10,00 0 pound s woul d probabl y contai n aquantit y les s tha n 10,00 0 pounds , eve n thoug hal l o f Ui e liste dflammabl e substance s ar e gase s or volatil e liquids

. Establishin g on e threshol dfo

r al l th e flammabl e substance s o n Ui

e lis t als o simplifie s Ui

e regulatory process
. Threshold Methodology for Explosives. EPA' s analysi s of explosive s indicate s tha t

ablas t wav e overpressur e o f 3. 0 ps i from adetonatio n coul dhav e potentiall y letha l effect s i n th e communit y beyon dth e fencelin e o f a facility

. Thi s overpressur e leve l coul d caus e seriou s structura l damag e t o buildings , lea dt o seriou s wound s from flyin g glass , an dpotentiall y caus e eardru mrupture

. EP

A use dUie scalin g la w o f distances , whic hrelate s quantit y o f explosiv e materia l an ddistanc e fo r a give n overpressure , t o estimat e th e quantit y o

f hig hexplosive s tha t

woul d produc e an overpressur e o f 3. 0 ps i at a distanc e o

f 10 0 meter s i n th e even t

o f adetonation

. Base do n thi s calculation , EP A decide dt o se t

Uie threshol dfo

r hig hexplosive s at

5,00 0 pounds

. Althoug hindividua l hig hexplosive s ma y vary i n thei r

explosiv e power , th e variation s ar e no t

very great ; hig h explosive s functio n b y detonatio n an d produc e simila r

results fo r agive n weight

. EP

A believes , therefore , Uia t i t i s appropriat e t o appl y on e threshol d quantit y t o al l hig hexplosives

. Thi s i s consisten t wit hth e approac huse db y BAT Ft o se t storag e distance s fo

r hig h explosives ; BAT

Fuse s on e tabl e o

f distance s fo

r al l hig hexplosives

. EP

A believe s tha t

thi s threshol dwil l appl y primaril y t o manufacturer s o f hig h explosives , wh o hav e large r quantitie s availabl e o n sit e wit hUie potentia l fo r catastrophi c releases

. User s o f explosive s (e.g. , fo

r industria l uses , construction , o r

mining ) woul d probabl y no t

hav e enoug hhig h explosive s presen t

at on e tim e t o mee t thi s threshold ; lowe r

quantitie s o n sit e an dexistin g regulation s woul dreduce th e likelihoo dof

catastrophi c event s at thes e facilities

. 3

. Othe r Threshol dOption s Th e Agency' s propose doption s fo r Ui e threshol dquantit y methodolog y relat e t o th e physical/chemica l propertie s o

f Ui e substance s an dth e specifi c hazar dtha t

eac hsubstanc eP. M

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present s (i.e. , toxicity , flammability, explosivity)

. EP

A recognizes however , tha t Uie impac t

of areleas e i n a particular instanc e may b e greate r

or lesse r dependin g upo n site-specifi c consideration s an dtha t

ther e may b e othe r factor s tha t

can b e accounte dfo

r i n amethodolog y t o determin e a threshol dquantity

. Thes e othe r factor s ma y includ e industr y clas s or facilit y typ e i n whic haparticula r chemica l i s typicall y handle dor

used

. Fo r example , athreshol dquantit y fo

r aparticula r chemica l coul db e adjuste dif i t i s typicall y handle da

t elevate d temperature s an dpressures
. Othe r factor s Uia

t migh t b e considere dunde r thi s approac hinclud e typica l SI C code s i n whic haparticula r

chemica l i s handled , typica l populatio n densit y an d sensitivity aroun dtype s o f facilitie s tha t handl e aparticula r

chemica l (e.g. , a chemica l ma

y b e typicall y use dat remot e locations , fa

r fromdens e populatio n center s o r

sensitiv e ecosystems) , or

proces s typ e i n whic ha chemica l i s typicall y involved

. Th e advantage s o

f thi s approac hwoul db e that i t woul dmor e specificall y tailo r threshol dquantitie s base do n commo n us e pattern s o

f asubstance

. Th e disadvantag e woul db e tha t thi s approac hwoul dno t

appl y t o ubiquitou s chemical s tha t

ar e use di n awid e variety o f applications , suc ha s chlorine , ammonia , an dsulfuri c acid , whic har e als o chemical s that , accordin g t o Agenc y data , ar e frequently involve di n accidenta l release s an dincident s involvin g death s an dinjuries

. A greate r disadvantag e t o thi s approac hi s tha t th e intrinsi c hazar do

f achemica l will stil l b e presen t

eve n whe n i t

i s use doutsid e ofa"typical " scenario ; i t woul dno t accoun t fo r th e potentia l fo

r chemica l accident s i n al l possibl e handlin g or us e scenarios

. Also , base do n curren t dat a limitations , EP

A believe s i t

i s no t feasibl e t o develo p amethodolog y tha t adopt s atypica l us e factor an dtha t woul dstil l b e applicabl e uniforml y nationwide

. Th e Agenc y request s comment s o n method s or supportin g dat awhic hwoul dpermi t th e us e o f th e aforementione dfactor s (o r othe r factors ) t o establis hthreshol dquantities

. I n developin g th e propose dthreshol d methodologies , Ui

e Agenc y als o considere dfou

r additiona l options , whic har e discusse dbelow

. Thre e o f thes e methodologie s ar e base do n intrinsi c propertie s o

f eac hsubstanc e (i.e. , physical/chemica l properties , toxicity , explosivity , flammability)

. Th e fourt hoptio n i s th e adoptio n o f threshold s alread y develope db y anothe r agency
. EP

A request s comment s o n thes e methodologies

. Vapor Quantity Method

(Toxics). EP

A considere dametho dsimilar t o tha t recommende db y OR

C fo r developmen t o f threshol dquantitie s fo

r toxics , a s describe dabove

. T o deriv e threshol d quantitie s b y thi s method , a concentratio n leve l equa l t o th e IDL H or it s equivalen t

wa s assume dt o b e reache dat

adistanc e o

f 10 0 meter s from th e sourc e o

f th e release. A release rat e tha t woul dproduc e tha t

concentratio n leve l at 10 0 meter s wa s calculate dusin g ai r dispersio n modelin g techniques

. Th e dispersio n modelin g use dwa s basedo n equation s presente di n Technical Guidance for

Hazards Analysis (EPA , FEMA , an dDOT , 1987)

. Fo r Ui e calculations , moderat e condition s ofa win dspeedo

f 1 0 mile s pe r

hou r (4. 4 meter s pe r

second) , atmospheri c stability D , an durba n condition s wer e assumed

. Th e duratio n o

f th e releas e wa s assume dt o b e 3 0 minutes , an da quantit y wa s calculate db y multiplyin g th e releas e rat e b y th e duration

. Threshol dquantitie s wer e assigne d base do n th e calculate dquantity , wit h 50 0 pound s a s th e lowe r

boun dan d 10,00 0 pound s a s th e uppe r bound

. Refe r t o th e technica l backgroun d document s i n th e docke t

fo r more informatio n o n threshold s develope d usin g thi s methodology

. Thi s metho do

f assignin g threshold s assume s tha t

th e tota l quantit y o

f th e substanc e become s airborne

. I t doe s no t conside r th e chemica l propertie s tha t migh t affect th e likelihoo do

f an accidenta l release

. Th e volatilit y o f th e liste dchemical s i s no t

take n int o account ; e.g. , aga s coul db e assigne dth e sam e threshol da s aliqui dwit h relativel y lo w volatility if th e toxicity o

f th e substance s were similar

. Thus , threshold s assigne db y thi s metho dran k th e chemical s primaril y b y toxicity

. Becaus e i t

seem s probabl e that , unde r mos t circumstances , aga s woul db e mor e likel y t o b e release dt o th e ai r tha n aliqui dwithalo w vapo r pressure , i t seem s reasonabl e tha t

gase s shoul dhav e lowe r threshold s tha n liquid s wit hth e sam e toxicity

. I

n addition , th e assumption s (e.g. , win dspeed , atmospheri c conditions , duratio n o f release ) use di n th e dispersio n model s hav e amajor

effect o n th e results ; man y different quantitie s coul db e calculate d fo r th e sam e chemical , dependin g o n th e modelin g assumption s made

. Th e condition s affectin g an actua l releas e coul dvary greatly ; therefore , th e result s o f chemical-specifi c calculation s suc h a s thos e use dunde r

thi s metho dmay hav e littl e relatio n t o wha t migh t happe n durin g an actua l release

. TPQ Method

(Toxics). EP

A als o considere dusin g th e TPQ s unde r EPCR A (SAR A Titl e III ) sectio n 30 2 a s th e threshold s fo r toxi c substance s unde r thi s rulemaking

. However , th e purpos e of

th e TPQ s i s t o trigge r reporting b y th e facilit

y t o stat e an d loca l emergenc y planner s o f Ui e presenc e o

f an EHS

. Th e communit y planner s the n carry ou t

an analysi s o

f th e hazard s pose db y th e substanc e an d us e thi s analysi s t o se t

prioritie s for

communit y planning

. Th e primar y purpos e o f th e threshol dquantitie s unde r thi s rule , however , i s t o trigger mandator y preventio n requirement s t o preven t th e catastrophi c accidenta l release o f aregulate dsubstance

. Therefore , threshold s unde r thi s rul e shoul drepresen t

quantitie s tha t

ar e sufficientl y hazardou s (i.e. , pos e aris k of catastrophi c event ) t o meri t th e requiremen t

fo r aris k managemen t

pla n o n asite-specifi c basis

. Thes e quantitie s shoul db e highe r

tha n th e TPQs , whic h onl y represen t

aleve l wher e th e hazar d shoul db e considere dfo

r plannin g purposes
. EHS s o n th e propose dlis t wit hTPQ s o

f 1,10 , or 10 0 pound s generall y hav e threshol dquantitie s o f 50 0 pound s i n today' s propose drule , basedo n th e revise dmethodology ; thos e wit hTPQ s o

f 50 0 pound s generall y hav e 1,000-poun dthresholds ; an dthos e wit h TPQ s of 1,000 pound s generall y hav e threshol dquantitie s o

f 5,00 0 pounds

. A TP Q o f 10,00 0 pound s generall y correspond s t o athreshol dof 10,00 0 pounds

. Alternative Overpressure Levels (Explosives). EP

A considere dbasin g th e threshol dquantit y fo

r explosive s o n othe r overpressur e levels ; fo

r example , a n overpressur e o

f 2. 0 psi , aleve l whic h coul dcaus e th e partia l collaps e of wall s an droof s o f houses , woul dgiv e a threshol dquantit y o

f 2,00 0 pounds

. However , EP

A believe s threshol d quantitie s calculate dusin g th e overpressur e leve l o

f 3. 0 ps i ar e consisten t

wit hquantitie s tha t

migh t hav e acatastrophi c effect i n cas e o f an accidenta l release

. Adopting OSHA's Thresholds Fo r chemical s liste dunde r

bot h OSHA' s chemica l proces s safet y standar dan dth e lis t

o f regulate d substance s unde r

CA A sectio n 112(r) , EP A considere dadopting,threshold s establishe db y OSHA

. Becaus e th e OSH A standar di s designe dt o protec t employee s fromhazard s associate dwith accidenta l release s of

OSHA-liste d chemical s i n th e workplace , EP A assume dtha t

th e OSH A threshold s represen t accepte dquantitie s that , if accidentall y released , woul db e reasonabl y anticipate dt o caus e death , injury , or seriou s advers e healt heffect s i n th e workplace

. EPA' s propose d threshold s ar e intende dt o b e protectiv eP.1 5

511 4 Federa l Registe r/ Vol

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ofth e publi c outsid e th e workplac e o r of f site

. EP A reviewe dth e threshold s unde r OSHA' s standar dfo

r chemical s o n both list s an ddetermine dtha t

EPA' s threshold s generall y ar e greate r tha n or equa l t o OSHA' s thresholds

. EP A als o note dtha t

ther e ar e 1 5 substance s fo r whic hEPA' s threshold s are lowe r tha n OSHA's

. Thes e substance s (CAS number s i n parentheses ) an dthei r OSH A threshold s are : Ammoni a (anhydrous ) (7664-41-7) , 10,00 0 pounds ; ammoni a(aqueou s solution , concentratio n greate r

tha n 4 4 percent ) (7664-41-7) , 15,00 0 pounds ; boro n trichlorid e (10294-34-5) , 2,50 0 pounds ; bromin e (7726-95-6) , 1,500 pounds ; chlorin e (7782-50-5) , 1,500 pounds ; chlorin e dioxid e (10049-04-4) , 1,000 pounds ; fluorine (7782-41-4) , 1,000 pounds ; formaldehyd e (50-00-0) , 1,00 0 pounds ; hydroge n chlorid e (anhydrous ) (7647-01-0) , 5,00 0 pounds ; hydroge n cyanid e (anhydrous ) (74-90-8) , 1,000 pounds ; hydroge n fluorid e (7664-39-3) , 1,00 0 pounds ; hydroge n peroxid e (concentratio n 5 2 percen t o r greater ) (7722-84-1) , 7,50 0 pounds ; hydroge n sulfid e (7783-06-4) , 1,50

0 pounds ; methy l chlorid e (74-87-3) , 15,00 0 pounds ; an dmethy l mercapta n (74-93

- 1) , 5,00 0 pounds

. Th e threshold s propose dtoda y fo r th e lis t o f regulate dsubstance s unde r CA A sectio n 112(r

) generall y ar e no t

equa l t o thos e fo r th e highl y hazardou s substance s liste dunde r

th e OSH A standard

. Threshold s tha t are protectiv e o f th e worke r

ma y diffe r fromlevel s Uia

t ar e protectiv e o

f th e public

. EP

A believe s i t

i s reasonable fo

r th e EP A threshold s generall y t o b e equa l t o or greater tha n th e OSH

A threshold s becaus e worker s generall y ar e locate d close r t o th e chemical s tha n th e public

. EP A recognize s tha t

OSHA' s threshold s fo r th e 1 5 substance s discusse dabov e wer e establishe db y rulemaking , whic h ma y indicat e aconsensu s o n th e amoun t that can b e reasonabl y anticipate dt o caus e seriou s advers e effect s no t onl y withi n th e workplac e bu t als o o n th e public

. Thi s consensu s may suppor t raisin g EPA' s threshold s fo r thes e 1 5 substance s t o OSHA' s levels

. However , EP A ha s propose dthreshold s lowe r tha n OSHA' s fo

r thes e 1 5 substance s becaus e EP

A believe s Uia

t Ui e scientifi c methodolog y applie dt o determin e Uie protectiv e threshold s fo

r thes e 1 5 chemical s shoul db e consisten t wit h tha t use dfo r th e remaining substance s o n Ui e EP A list

. B y adoptin g a consisten t methodology , EP

A can ensur e tha t

ther e i s areasonable relationshi p betwee n th e threshold s fo r substance s o n EPA' s lis t

tha t ar e o n OSHA' s lis t

an dthos e Uia

t ar e not , an d betwee n substance s liste di n th e initia l

rulemakin g an dthos e adde d subsequentl y b y petitio n or othe r revision

. Th e Agenc y request s comment s o n thes e issue s and , give n th e exten t t o whic hthi s rul e an dth e rul e promulgate db y OSH

A overlap , th e degre e tha t

accidenta l releases of

toxics , flammables an dexplosive s an dthei r correspondin g offsit

e effect s wil l b e reducedb y th e OSH

A rule

. EP A request s comment s o n th e propose dmethodologie s fo r establishin g threshol dquantitie s fo

r toxic , flammable, an dexplosiv e substance s covere di n thi s propose drule

. EP A als o requests comment s o n option s considere dfo

r settin g thresholds

. 4

. Determinatio n of

Presenc e o f Threshol dQuantity Th e purpos e o

f th e threshol d determinatio n i s t o evaluat e (a ) whethe r afacilit y i s covere dfo

r aspecifi c regulate dsubstanc e an d(b ) whethe r a particular locatio n withi n th e facilit y i s subjec t t o regulation s base do n th e presenc e o

f th e substance

. I n decidin g no w th e presenc e o

f athreshol d quantit y ofaliste dsubstanc e at a facilit y shoul db e determined , EP A considere dseveral possibilitie s an d reviewe dth e method s use db y othe r agencie s an dprograms
. Unde r sectio n 30 2 o f EPCR A (SAR A Titl e III) , afacilit

y i s covere dif

th e tota l quantit y o

f an EH S presen t o n sit e at an y on e tim e i s i n exces s o f it s TPQ

. Ne w Jersey' s threshol dals o i s applie dt o th e maximu mquantit y o n sit e at an y time

. Unde r Delaware' s approach , facilitie s mus t iletermin e th e maximu mquantit y o f atoxic chemica l tha t

coul db e release da t on e time , usin g guidanc e provide db y th e stat e t o accoun t fo r facility-specifi c factors

. I

f thi s potentia l releas e quantit y i s greate r tha n th e threshold , th e facilit

y i s covere db y th e Delaware RM

P regulations

. OSH

A propose dtha t

th e threshol dquantit y b e base do n th e amoun t

use di n aprocess , rathe r tha n th e quantit y o n site , t o determin e whethe r

athreshol dquantit y i s present , wher e aproces s i s define da s "an y use , storage , manufacturing , handling , processing , or

th e on-sit e movement

. . . , o r

combinatio n o

f thes e activities. " Vessel s tha t

ar e intercennecte dor

vessel s tha t

ar e no t intercennecte dbu t

coul db e involve di n apotentia l releas e ar e considere da singl e process
. EP A i s proposin g t o appl y th e threshol dquantit y t o th e maximu mtota l quantit y o

f asubstanc e i n aprocess , usin g th e sam e definitio n use db y OSHA

. Thi s definitio n woul dappl y t o th e maximu mquantity , at an y on e time , i n asingl e vessel , or

i n severa l vessel s tha t coul db e involve dat

on e tim e i n a potentia l release , o r

i n agrou p o

f interconnecte dvessels

. Interconnecte d vessel s coul dinclude , fo

r example , storag e tanks , surg e tanks , o r weig h tank s tha t may b e connecte dt o anothe r vesse l o r processin g syste mb y pipes , pumps , o r

othe r conveyanc e equipmen t use dt o transfe r

asubstanc e fro

mon e vesse l t o another

. Th e propose d approac ht o determinin g whethe r a facilit y o r locatio n i s covere dfocuse s o n th e quantit y o

f asubstanc e Uia

t coul db e release di n asingl e accident

. Fo r example , if

afacilit y use s 30 0 pound s o

f chlorin e i n on e process , use s 15 0 pound s t o trea t

wastewater , an dstore s 60 0 pounds , th e facilit

y woul dhav e a tota l of 1,05 0 pound s quantit y o n site

. Th e propose dthreshol dquantit y fo r chlorin e i s 1,000 pounds

. I f al l o f Ui e chlorin e i s kep t

an duse di n asingl e area , wher e afire o r

explosio n coul d affect th e chlorin e cylinders , mor e tha n 1,00 0 pound s hav e th e potentia l o f bein g release di n asingl e incident , thereb y exceedin g Ui

e threshold

. If

, however , th e proces s area , storag e area , an dwastewate r

treatmen t

facilit y ar e widel y separate d(an dno t otherwis e interconnecte db y pipes , pumps , or othe r conveyanc e equipment) , asingl e inciden t woul db e unlikel y t o lea dt o a larg e chlorin e release

. EP A als o believe s tha t considerin g onl y th e quantit y i n on e vessel o r

interconnecte dvessel s woul dno t

b e sufficientl y protectiv e i n som e cases
. Fo r

example , debri s fro

man explosio n coul dpunctur e anearb y container , o r

afire coul dcaus e a numbe r o f container s o r

pipe s t o rupture

. Therefore , EP

A i s als o proposin g tha t

threshol ddeterminatio n conside r al l vessel s locate dsufficientl y clos e t o eac hothe r

Uia t the y migh t

b e involve di n areleas e at

on e time

. EP

A believe s thi s approac hi s relativel y simpl e t o implemen t

an dverif y an dals o reasonabl y approximate s th e potentia l releas e quantity

. Th e Agenc y recognizes, however , Uia

t thi s metho do

f threshol ddeterminatio n woul dno t addres s som e potentiall y hazardou s situations

. Different

material s withth e sam e characteristi c (e.g. , flammability) , o r different material s wit hvariou s hazards , tha t

ar e store di n clos e proximit y t o eac hothe r

bu t ar e al l store di n quantitie s belo w th e threshol d quantity , migh t

pos e apotentia l hazar d t o th e community , bu t

th e threshol d quantit y woul dno t

b e exceede dbecaus e eac hsubstanc e i s considere d individually

. EP

A believe s i t

i s no t feasibl e t o attemp t

t o addres s al l potentia l hazard s of

combination s o

f substances

. EP

A request s comment s o n th e propose dapproach

.P.1 6

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EP A considere dapplyin g th e threshol dquantit y t o th e tota l quantit y o n sit e at afacility , a s unde r

EPCR A (SAR A Titl e III) sectio n 302

. A facilit y woul db e covere dif

i t ha dpresen t

an amoun t o f aliste dsubstanc e exceedin g it s threshol dquantit y regardles s o f it s locatio n or

distributio n o n th e site

. Thi s metho di s clear

an dunambiguous ; n o complicate dformula s o r

definition s nee dt o b e applied

. Th e Agenc y believes , however , tha t

i t i s unlikel y tha t th e content s o

f severa l vessel s tha t are no t interconnecte dan dtha t

ar e widel y separate dwoul db e release d simultaneously , causin g acatastrophi c event

. Therefore , usin g th e tota l quantit y o n sit e fo

r threshol dquantit y determinatio n appear s t o b e an overl y conservativ e approach

. Anothe r approac hconsidere dwa s t o bas e determinatio n o

f th e threshol do n th e maximu mquantit y o

f Ui e regulate d substanc e capabl e o

f bein g releasedi n a worst-cas e accidenta l release

. Thi s approac hi s use db y Delaware fo r toxic chemicals

. Unde r

th e Delawar e regulation , Ui

e facilitie s mus t

calculat e aworst-cas e potentia l releas e quantit y base do n formula s provided

. Som e difficultie s hav e bee n reporte dwit hthi s approach ; fo

r example , th e calculation s requir e atechnica l knowledg e no t availabl e at

th e full rang e o

f potentiall y covere dfacilities

. Again , EP A believe s thi s approac hmay presen t enforcemen t an dcomplianc e problem s du e t o th e lac k o f easil y verifiabl e criteria

. EP A request s comment s o n Ui e propose d definitio n fo

r threshol dquantitie s an d th e alternativ e approache s considere da s options

. 5

. Threshol dExemption s EP A i s proposin g severa l exemption s t o limi t th e quantitie s o

f substance s include di n th e threshol d determination

. EP

A woul dadop t

th e exemptio n applie dunde r EPCR A (SAR A Titl e III) whic hdoe s no t conside r substance s i n mixture s if the y represen t les s tha n on e percen t

o f th e mixtur e b y weight

. Regulate d substance s i n suc hdilut e solution s ar e unlikel y t o pos e ahazar dt o th e communit y i n Ui

e even t of an accidenta l release

. In addition , i t

migh t no t b e feasibl e i n man y case s fo

r facilitie s t o calculat e smal l quantitie s o f substance s tha t ma y b e containe di n mixtures

. EP A als o i s proposin g t o exemp t substance s containe di n "articles " from Ui e threshol ddetermination

. Th e OSH A definitio n o

f a n articl e woul db e use d (2 9 CF R1910.1200(b))

. Batterie s (afte r thei r manufacture ) woul db e considere d article s unde r

thi s definition

. I n addition , EP

A i s proposin g t o exemp t substance s use dfo

r th e followin g purpose s frominclusio n i n th e

threshol ddetermination : substance s tha t are astructura l componen t o f th e facility ; substance s use dfo r routin e janitoria l maintenance ; substance s i h consume r products ; an dsubstance s i n wate r draw n fromth e environmen t o r municipa l sources
. EP

A als o woul d exemp t activitie s i n laboratorie s whe n unde r Ui e supervisio n o

f atechnicall y qualifie dperson
. EP

A consider s i t

les s likel y Uia t substance s store di n thes e exemp t form s coul db e involve di n accidenta l release s o

f acatastrophi c nature

. Thes e propose dexemption s paralle l th e exemption s provide dunde r EPCR A (SAR A Titl e III) section s 31 1 an d31 2 fo r threshol dcalculations

. EP A recognizes tha t unde r EPCR A (SAR A Titl e ffl) sectio n 302 , ther e ar e n o similar exemption s fromthreshol d determination

. However , a s note d previously , EPCR

A (SAR A Titl e III) sectio n 30 2 doe s no t

requir e facility

specifi c preventio n measures , i n contras t t o th e requirement s o

f CA A sectio n 112(r)

. EP

A believe s thes e exemption s ar e necessary t o avoi d coverin g facilitie s whos e us e ofth e substance s doe s no t

meri t th e substantia l regulation s require dunde r th e CA A an dfacilitie s wh o d o no t directl y us e th e substanc e becaus e i t i s containe di n an article , i n proces s water , i n othe r products , o r

i n specifi c supervise dsituations

. Fo r example , withou t th e articl e exemption , car dealer s an dservic e station s coul db e covere dbecaus e o

f th e aci di n ca

r batteries

. Unde r

EPCR A (SAR A Titl e IH ) sectio n 302 , facilit

y notificatio n t o loca l an dstat e emergenc y planner s ma y b e appropriat e i n orde r

fo r the mt o conside r Ui e ris k t o th e community , bu t mandator y preventio n requirement s i n al l case s woul db e excessive

. I n addition , EP

A i s proposin g tb exemp t liste dflammabl e substance s use dsolel y fo

r facilit y consumptio n a s fuel

. Thi s exemptio n i s consisten t wit h OSHA' s approac hi n it s propose drul e fo r proces s safet

y management

. 6

. Consideration s fo

r Mixture s EP A note s tha t

certai n liste d substance s ar e covere donl y if the y ar e i n concentration s b y weigh t abov e specifie dlevels ; fo

r example , hydrochlori c aci dwoul db e covere d onl y whe n i t

i s i n solutio n at

a concentratio n o

f 2 5 percen t

o r greater , aqueou s solution s o

f ammoniamus t

b e considere donl y if

th e concentratio n i s 2 0 percen t

or greater , an dhydroge n peroxid e solution s mus t

b e considere d if th e concentratio n i s greate r tha n 5 2 percent

. Stationary source s woul dno t b e require dt o estimat e quantitie s o f mor e dilut e solution s o f thes e substances

. Thes e concentration s represen t typica l industr y handlin g o f thes e mixtures

. Fo r

mixture s o r solution s o

f othe r liste dsubstances , determinatio n o

f whethe r athreshol d quantit y i s presen t

woul db e base do n th e quantit y o

f Uie liste dsubstanc e i n Ui e mixtur e o r

solution

. Fo r

example , fo r a2 5 percen t

solutio n of

aliste d substanc e wit hathreshol dquantit y o f 50 0 pounds , mor e tha n 2,00 0 pound s of th e solutio n woul db e neede dt o excee d Ui e threshol dfo

r th e liste dsubstance

. IV

. Othe r Issue s A. State Programs Th e Ac t encourage s state s t o develo p program s t o implemen t

CA A statut e requirements

. EP

A wil l b e publishin g guidanc e t o assis t

i n th e developmen t

o f stat e program s an di n th e implementatio n of

sectio n 112(r) requirements

. Sectio n 112(1)(1 ) indicate s tha t state s may submi t

Stat e Program Plan s outlinin g th e implementatio n an d enforcemen t

o f sectio n 112(r) ' requirements

. Th e chemica l lis t an d reporting threshold s EP

A adopt s wil l provid e aminimu mse t

o f requirements fo r stat e program s t o adopt

. States , however , ar e no t

restricted fromhavin g amor e stringen t

programtha n th e on e EP A i s proposing

. Severa l state s hav e develope dthei r ow n chemica l acciden t

preventio n regulations

. A s previousl y noted , California , Delaware , an dNe w Jerse y alread y hav e chemica l acciden t preventio n regulations Uia t require facilitie s t o develo p an dimplemen t ris k management

plans

. Fo r

eac ho f thes e programs , th e applicabilit y ofth e regulations i s determine db y alis t o f chemical s wit hreporting thresholds

. Th e Californi aprogramuse s th e lis t an d threshold s establishe dunde r EPCR A (SAR A Titl e III) sectio n 302 ; Uia t is , Ui e Califomi aprogra mcover s al l 36 0 extremel y hazardou s substance s o n th e EPCR A (SAR A Titl e ID

) sectio n 30 2 lis t at thei r TPQs

. Ne w Jerse y ha s develope d it s ow n lis t

of chemical s an dthresholds

. Delawar e ha s als o develope daseparat e list ; Delaware' s threshold s ar e dependen t

o n bot hUie quantit y of

Ui e substanc e q n sit e an dth e distanc e t o th e neares t population

. I

f a n establishe d stat e programdoe s no t

includ e al l th e substance s at

th e threshol dquantit y se t b y EP A (or at alower , mor e stringen t threshold) , th e progra mwoul dhav e t o b e revise dt o brin g i t

int o complianc e wit hUi e Federa l requirement s whe n the y ar e promulgated

.P.1 7



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ProposedRule s
B. OSHA's List

of Highly Hazardous Chemicals In developin g th e propose dlis t o f substance s an dthresholds , EP A considere dth e possibilit y of adoptin g th e lis t o f highl y hazardou s chemical s an dthreshold s OSH

A list s fo r it s chemica l proces s safet

y standard

. EP

A conducte dit s analysi s base do n th e propose dOSH

A standar davailabl e at th e time , wit hcoordinatio n wit hOSH A betwee n thei r

proposa l an dfinal versions

. However , OSHA' s lis t doe s no t includ e al l th e substance s mandate dfo r listin g b y Congress

. It

doe s no t includ e al l EHS s tha t

mee t EPA' s propose d criteri aan dinclude s severa l substance s tha t EP A canno t lis t unde r th e Act

. It als o include s anumbe r

o f substance s tha t ar e no t i n commercia l production

. EP A i s require dt o conside r

likelihoo d o f arelease; substance s tha t ar e no t i n commercia l productio n woul db e unlikel y t o b e release di n significan t quantities

. Therefore , th e OSH A lis t doe s no t mee t EPA' s Congressional mandate

. Approximatel y 20 percen t o f OSHA' s lis t

i s mad e u p o

f reactiv e chemicals

. EP

A i s currentl y considerin g whethe r reactiv e chemical s pos e a potentia l threa t

t o th e publi c healt hor welfare (a s oppose dt o worke r safety) , an di s deferrin g listin g suc hsubstance s fo r th e accidenta l releas e provision s pendin g furthe r

analysi s of

thei r hazards

. Fo r

thes e reasons , EP

A determine dth e OSH

A lis t coul dno t

b e adopte di n it s entirety

. EP A an dOSH

A continu e t o wor

k togethe r t o coordinat e thei r list s t o Ui

e exten t possible

. EP A ha s propose dth e sam e metho d a s OSH A fo r determinin g whethe r

th e quantit y ofasubstanc e at afacility exceed s th e threshold

. However , EP A an dOSH A use ddifferent

method s t o assig n threshol dquantities

. EPA' s propose dlis t

include s 6 1 chemical s tha t als o ar e liste db y OSH

A (5 0 o n EPA' s lis t o f toxic substance s an d1 1 o n Ui e lis t o f flammable substances)

. Of Uie substance s Uia

t ar e liste db y bot hOSH

A an dEPA , 1 0 (9 toxic s an d1 flammable ) hav e identica l thresholds

. EPA' s threshold s ar e highe r

tha n OSHA' s fo

r 3 6 substance s (2 6 toxic s an d1 0 flammables) ; becaus e OSHA' s threshold s relat e t o worke r protection , whil e EPA' s ar e intende dt o protec t th e community , i t

i s reasonabl e Uia

t EPA' s threshold s shoul db e higher

. However , OSHA' s threshold s ar e highe r fo r 1 5 substances

. C Relationship to EPCRA (SARA Title III) Section 302/303 Unde r EPCR A (SAR A Titl e HI

) sectio n 302 , EP A publishe dalis t

o f extremel y hazardou s substance s (EHSs ) an d threshol dplannin g quantitie s (TPQs)

. Facilitie s wit hEHSs , i n quantitie s exceedin g Ui

e TP Q mus t

notif y Ui e Stat e Emergenc y Respons e Commissio n an d Local Emergenc y Plannin g Committees

. Identificatio n o

f facilitie s wit hEHS s abov e thei r

TPQ s i s intende dt o provid e loca l emergenc y planner s wit habasi s fo r farthe r analysi s of

th e potentia l dange r pose db y thes e facilities

. Th e TPQ s d o no t

trigger an y specifi c requirements , othe r

tha n notificatio n an ddesignatio n o

f afacilit y coordinator , fo r facilitie s wit hEHSs , no r

d o the y trigger an y specifi c emergenc y plannin g requirement s at

thefacility other

tha n cooperatio n withth e stat e an dloca l planner s i n th e plannin g process
. However , som e facilitie s alread y ma y b e institutin g preventio n programs , base d especiall y o n th e heightene dawarenes s o f hazard s tha t

ha s resulte dfromEPCR

A (SAR A Titl e III) sectio n 30 3 activities

. Th e mai n distinctio n betwee n EPCR A (SAR A Titl e III) sectio n 30 3 requirement s an dUi

e CA A requirement s i s tha t EPCR A (SAR A Titl e III) sectio n 30 3 focuse s o n communit y planning , whil e th e CA

A focuse s o n plannin g at th e facilit y fo r acciden t preventio n an d response
. Th e lis t

of substance s an d threshol dquantitie s bein g propose d unde r CA A sectio n 112(r

) trigger s mandatory preventio n requirement s b y facilitie s fo

r preventio n o

f accidenta l releases

. EPA , therefore , believe s i t i s appropriat e tha t

Ui e lis t o f toxic chemical s unde r

CA A sectio n 112(r

) shoul db e limite dt o gase s an dvolatil e liquid s wit hevidenc e o

f production , unlik e th e EH S list , whic hi s base donl y o n toxicity , an dtha t

Ui e threshold s fo

r toxic chemical s unde r

CA A sectio n 112(r) shoul db e highe r

tha n th e TPQ s unde r EPCR A (SAR A Titl e III) sectio n 302

. I n addition , determinatio n of th e presenc e o

f aTP Q o f an EH S unde r EPCR A (SAR A Titl e ffl) sectio n 30 2 i s base do n Ui

e tota l quantit y o

f Ui e EH S at Ui e facility , whil e unde r

CA A sectio n 112(r) , th e propose dmetho do f threshol ddeterminatio n i s basedo n th e quantit y ofth e regulate dsubstanc e i n a process
. EP

A believe s i t

i s appropriat e unde r EPCR A (SAR A Titl e III) sectio n 30 2 t o identif

y facilitie s basedo n Ui

e tota l quantit y o n site ; emergenc y planner s can the n tak e factor s suc ha s locatio n an ddistributio n o f vessel s int o accoun t whe n settin g prioritie s fo r planning

. O n th e othe r

hand , EP A believe s i t

i s mor e appropriat e unde r CA A sectio n 112(r) , becaus e o f Ui e associate drequirements , t o conside r th e quantit y tha t

ha s th e potentia l t o b e releasedi n asingl e acciden t an dcaus e seriou s effect s beyon dth e fenceline

. EP A may decid e t o lis t

flammabl e an d explosiv e substance s unde r EPCR A (SAR A Titl e III) sectio n 302 , followin g completio n o

f it s analysi s o

f th e hazard s o f suc hchemicals

. Becaus e o f th e different purpose s of

EPCR A (SAR A Titl e III) sectio n 30 2 an dCA A sectio n 112(r) , i t may b e appropriat e t o hav e somewha t

differen t list s an dthreshold s unde r EPCR A (SAR A Titl e III) sectio n 302

. Fo r example , t o provid e loca l emergenc y planner s wit hsufficien t informatio n t o allo w the mt o se t plannin g prioritie s fo

r thei r communities , EP

A ma y us e les s stringen t criteri afo

r listin g (e.g. , blastin g agent s a s wel l a s hig hexplosive s ma y b e listed ) an dse t

lowe r threshold s (e.g. , threshold s fo

r explosive s ma

y b e se t usin g alowe r

overpressur e level , suc h a s 1. 0 ps i o r

2. 0 psi ) unde r

EPCR A (SAR A Titl e III) sectio n 302

. D. Agricultural

Nutrient Exemption Unde r CA A sectio n 112(r) , EP

A i s authorize dt o establis hhighe r threshol d quantitie s for , o r

exemp t entirely , chemical s use da s agricultura l nutrient s whe n hel db y farmers

. EP A believe s tha t ammoni ai s th e onl y chemica l o n Ui e propose dlis t

of substance s tha t

woul d b e use da s a n agricultura l nutrien t an d thu s coul db e subjec t

t o Ui e highe r threshol dor

exemption

. EP

A i s proposin g t o exemp t

ammoni afromth e requirements of

thi s rul e whe n hel db y afarmer a s an agricultura l nutrient

. EP A i s proposin g thi s exclusio n fo r tw o reasons
. First , th e farm s Uia t us e ammoni aa s afertilize r

ar e primaril y growin g corn , wheat , an dcotton , an d involv e larg e acreage s an dth e ammoni a i s intentionall y release dt o th e environment

. Second , man y element s o f chemica l acciden t

preventio n program s may no t b e directl y relevan t

t o Ui e us e o f ammoni aa s afertilizer

. EP A request s comment s o n th e propose dexemption

. EP A note s tha t

far mcontractor s wh o sel l ammoni aa s afertilize r woul db e coveredb y today' s propose drule

. E. Information Gathering Efforts Befor e EP A began writin g it s propose drule s fo

r accidenta l release prevention , Ui

e Agenc y decide dt o see k informatio n fromthos e alread y implementin g simila r

regulations. EP

A staf f me t extensivel y wit hofficial s i n thre e state s an dhel dinterview s wit h seve n facilitie s Uia

t hav e develope d RMP s unde r

stat e laws

. T o gathe r

mor e information , EP

A hel deigh t

focu s groups , five wit hfacilitie s (tw o eac hi n Ne w Jerse y an dCalifornia , on e i n Delaware) , an dthre e wit hadministerin g agenc y official s i n California , t o elici t thei r opinion s o n th e regulation s an d thei r idea s abou t

th e mos t usefu lP.1 8

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programcomponents

. Afte r analyzin g th e result s o

f thes e meetings , EP

A hel d atwo-day seminar

o n issue s Uia

t hav e arise n at Ui e stat e level

. Official s from

. , California , Delaware , an dNe w Jersey , a s wel l a s Minnesota , Texas , Ne w York , an dWisconsin , attende dth e meetings

. On Ui e secon dday , otiie r

group s tha t ha dexpresse da n interest , includin g trad e associations , labo r

unions , environmentalists , an dorganization s o f publi c officials , joine dth e discussion

. Participant s wer e concerne dtha t t o th e exten t possible , Ui

e OSHA , EPA , an d stat e chemica l list s an drelate d regulation s shoul db e consistent

. Several facilitie s indicate dtha t the y woul dlike Ui

e regulation s arrange ds o tha t i f the y are i n complianc e wit hon e rule , the y woul db e i n complianc e wit h al l rules , at

leas t fo r aspecifi c chemical

. I t wa s note dtha t

th e chemica l lis t shoul db e base do n criteria ; threshold s shoul db e develope do n arisk-base d system

. I n general , th e focu s grou p participant s foun dth e threshold s use d i n thei r state s reasonable , regardles s o f th e actua l threshol dquantities , whic h varie dfromstat e t o state

. A report o n thi s informatio n gatherin g effor t entitle d Clean Air Act of 1990, Chemical Accident Release Provisions, Report on Focus Groups and

Round Table Discussions, transcript s o f th e focu s grou p sessions , an dareport o n th e two

day seminar

ar e availabl e i n th e docket

. V

. Petition s for

Addition s an dDeletion s A. Information Required

from Petitioner Th e Ac t require s EP

A t o revie w th e lis t a t leas t every five years ; EP

A ma y revis e th e lis t

eithe r throug hpetition s or b y Agenc y initiative

. EP

A i s require dt o develo p procedure s fo

r th e additio n an d deletio n o f substance s fromth e list ; thes e procedure s ar e t o b e consisten t withthos e applicabl e t o th e lis t i n CA A sectio n 112(b)

. EP A will conside r

an drespon dt o petition s t o modif

y th e lis t o f regulate d substance s fo

r accidenta l releas e preventio n withi n 1 8 month s o f submissio n o

f th e petition

. Fo r

EP A t o complet e it s revie w o

f petition s an d publis hth e result s o

f it s determination s i n atimel y an defficient

manner , th e dat apresente di n th e petitio n mus t b e complet e an dtechnicall y sound

. EPA' s revie w woul db e facilitate dif th e petitione r present s Ui

e informatio n i n th e orde r liste dbelow

. o Name and

address of

the petitioner and a brief description of

the organization(s) that

the petitioner represents, if

applicable. o Name, address, and

telephone number ofa contact

person for

the petition. o Common chemical name(s), common synonym(s). Chemical Abstracts Service (CAS) number, and chemical formula and

structure. Th e CAS numbe r

i s auniqu e numbe r assigne dt o chemica l substance s b y th e American Chemical Society Chemica l Abstract s Servic e Registr

y System

. Th e CAS number s ar e independen t o f nomenclatur e an dhav e n o chemica l significance

. The y ar e assigne da s eac h ne w chemica l enter s th e CAS Registr y System

. ° Action requested. Th e petitione r mus t identif y whethe r

Ui e request i s t o ad dt o o r delet e fro mth e lis t o f regulate dsubstance s fo

r accidenta l releas e prevention

. c » Rationale supporting the petitioner's position. Eac hpetitio n mus t presen t adiscussio n o

f th e rational e t o ad do r delet e eac hsubstanc e base d upo n th e dat apresente dan dthei r relationshi p t o th e criteri afo r additio n or deletion

. A short

summary o

f th e rational e mus t

b e submitte dalon g wit h amor e detaile dnarrativ e tha t include s adiscussio n o

f th e availabl e dat ao n th e potentia l fo

r acut e advers e huma n healt heffect s tha t

occu r a s aresul t

o f exposur e t o th e substance

. Physica l an d chemica l dat arelate dt o th e likelihoo d o f accidenta l release s an dth e magnitud e of huma n exposur e als o shoul db e discussed

. For

apetitio n t o add , dat a mus t b e submitte dshowin g tha t th e criteri afo r listin g are met

. Chemical s mee t th e criteri afo

r listin g i f the y mee t th e mammalia n toxicity criteri afo r listin g a s EHS s (discusse di n Sectio n II I C ofthi s preamble) , are gase s or liquid s withvapo r

pressur e o

f 0. 5 m mH g or highe r unde r ambien t conditions , an d ar e i n productio n i n commercia l quantities

. Les s volatil e chemical s tha t mee t th e toxicity criteri awil l b e considere dfo

r listin g i f the y hav e a histor y o f involvemen t

i n accident s tha t cause ddeathor

injury

. Fo r

flammabl e chemicals , dat ashoul dindicat e tha t th e substance s ar e flammabl e gase s unde r ambien t conditions , or

tha t the y ar e liquid s wit hboilin g poin t belo w 100 ° F (37. 8 °C ) an dflashpoin t

belo w 7 3 ° F (22. 8 °C)

. Fo r

apetitio n t o delete , dat a mus t b e submitte ddemonstratin g tha t th e substanc e woul dno t

reasonabl y b e expecte dt o caus e death , injury , o r seriou s advers e effect s t o huma n healt h o r th e environmen t

i n th e even t

o f an accidenta l release

. Availabl e dat ao n al l hazard s presente db y th e chemica l shoul db e included

. o Supporting data. Th e petitione r mus t provid e EP

A wit hsufficient informatio n t o suppor t

scientificall y hi s o r he r reques t t o ad dt o o r

delet e from th e lis t o f regulate dsubstance s fo

r accidenta l releas e prevention

. Duplicat e copie s of al l materia l submitte dan dan Englis htranslatio n o

f an y informatio n publishe di n aforeig n languag e shoul d b e include dwit hUi

e petitio n i n orde r t o expedit e Ui

e revie w process
. Al l dat apresente dmus t

mee t basi c criteri afo r acceptabl e scientifi c quality

. Thes e include , bu t

ar e no t limite dto , appropriat e stud y design , qualit y ofth e scientifi c approach/method , appropriat e qualit y assuranc e an dqualit y contro l procedures , an dappropriat e statistica l analyses

. Th e supportin g dat afo

r th e petitio n mus t contain , at

aminimum , th e followin g elements : ° List of supporting documents. Th e petitione r mus t includ e asummary lis t o f al l supportin g document s include d wit hth e petition

. ° Literature searches. Th e petitione r mus t includ e aprinte dcop y o f al l literatur e searche s conducte dt o identif y dat aavailabl e fo

r th e substances , includin g identification o f th e databasefs ) searched , th e searc h strategy , date s covered , an dprinte d results

. Th e literatur e searche s mus t hav e bee n conducte dwithi n si x month s prio r t o submissio n o

f th e petition

. o Effects data. Eac hpetitio n mus t includ e summary table s identifyin g al l studie s cited

. Th e petitione r mus t submi t printe dcopie s of

th e studie s cite do n thes e tables

. Th e report s o f effect s dat ashoul dinclud e al l availabl e report s o n effect s o

f short-termexposur e t o th e chemica l an dshoul dno t b e limite dt o report s o n th e effec t fo r whic h th e chemica l wa s listed

. Huma n studies , anima l studies , othe r

environmenta l effect s studies , an dsupplementar y dat a suc ha s result s fromshort-termin vitro tests , toxicokineti c studies , comparativ e metabolis mstudies , structure-activit y relationships , an dothe r

relevan t toxicologica l studie s may b e submitted

. Studie s will b e evaluate dfo r adequac y usin g standar dEP A guidanc e document s an dbasi c toxicologi c principles

. EP

A wil l plac e greate r confidenc e i n studie s tha t hav e bee n publishe di n peer-reviewe dscientifi c journal s or

books

. I n addition , Ui

e petitione r ma y b e awar e o

f supportin g studies , data , o r

report s Uia

t wer e no t publishe di n peer-reviewe djournal s or books

. In suc hcases , th e petitione r shoul dsubmi t

aprinte dcop y o

f eac h relevan t non-peer-reviewe dcitation

. Example s o

f suc hcitation s ma

y includ e proceeding s of

scientifi c meetings , studie s conducte dat

an industria l sit e fo r interna l purposes , an dsom e government-sponsore dreports / assessments

. o Exposur e an dacciden t histor y data

. Th e petitio n shoul dinclud e dat arelated t o th e potentia l fo

r seriou s advers eP.1 9

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ProposedRule s
huma n healt ho r

environmenta l effects

. Relevan t physica l an dchemica l propertie s ofth e substanc e (e.g. , boilin g poin t an dvapo r

pressure) shoul db e included , wit hliteratur e citations

. Ai r dispersio n modelin g result s may b e included

. Assumption s an ddat ause d fo r Ui e modelin g shoul db e presente d clearly , an ddocumentatio n fo r th e mode l use dshoul db e include di n th e submission

. Historica l dat ao n accident s involvin g th e substanc e may b e included , clearl y citin g Ui e source s o

f th e data

. B. Petition

Process Th e guidanc e presente di n thi s propose drulemakin g i s intende dt o provid e agenera l framework fo r determinin g petitio n adequacy

. Becaus e mos t petition s wil l hav e specifi c issue s no t covere db y thi s guidance , individual s wishin g t o petitio n EP A t o modif y th e lis t o f regulate dsubstance s fo r accidenta l releas e preventio n ar e encourage dt o reques t

apre-petitio n conferenc e wit hEPA

. Suc hameetin g woul dfacilitat e submitta l o f complet e an dtechnicall y soun dpetitions

. T o arrang e apre-petitio n conference , pleas e contac t CA A 112(r) Petitio n Coordinator , Chemical Emergenc y Preparednes s an dPreventio n Offic e (OS-120) , 40 1 M Stree t

SW. , Washingto n D

C 20460

. At

th e tim e a pre-petitio n conferenc e i s requested , th e potentia l petitione r

mus t b e prepare dt o submi t apropose dagend afo

r th e meetin g an dalis t

of participants

. A petitio n t o modif

y th e hs t o f regulate dsubstance s fo

r accidenta l releas e preventio n unde r

sectio n 112(r

) o f th e Clea n Ai r Ac t shoul db e sen t

t o th e followin g addres s t o expedit e it s review

. Environmenta l Protectio n Agency , Chemical Emergenc y Preparednes s an dPreventio n Office , OS-120 , 40 1 M Street , SW. , Washington , D

C 20460

. Upo n receip t

o f apetition , EP

A wil l first revie w th e petitio n fo

r completeness

. I

f th e petitio n i s foun dt o b e incomplete , EP

A wil l retur n i t

t o th e petitione r identifyin g th e omissions

. Th e petitione r

ma y correc t Ui e deficiencie s an dresubmi t th e petition

. Thi s actio n wil l b e considere d equivalen t

t o submittin g ane w petition ; thus , EP A wil l hav e 1 8 month s t o revie w th e petitio n content s an dpublis h adecisio n t o gran t

or den y th e petition

. I f th e petitio n i s foun dt o b e complete , EP A propose s t o publis hth e followin g tw o notice s i n th e Federa l Register : 1

. Notice of

Petition Receipt

and Request for Comments: Thi s notic e wil l announc e tha t

acomplet e petitio n ha s bee n receive dan dwil l identif y th e following : th e petitioner , th e actio n requeste d(regulate dsubstance , addition/deletion) , Ui

e rational e an d summary o

f th e ke y dat asubmitte di n suppor t ofth e petition , an dth e lis t o f studie s submitte db y th e petitione r t o suppor t th e request. In respons e t o thi s notice , EP A wil l reques t

tha t intereste d partie s submi t

additional , pertinen t scientifi c informatio n Uia t wa s no t identifie db y th e petitione r if suc h informatio n migh t

assis t EP A i n makin g th e decisio n t o gran t

o r den y th e petition

. Additiona l dat awil l b e accepte dfo

r sixty day s followin g putelicatio n o

f thi s notice

. Th e reques t fo r informatio n wil l constitut e arequest fo r publi c comment s o n th e petition

. Al l pertinen t informatio n an dcomment s receive dwil l b e addresse di n th e notic e grantin g or

denyin g th e petition

. 2

. Publication of

Decision: Thi s notic e wil l announc e EPA' s decisio n t o gran t or den y aspecifi c petition

. EP A anticipate s publishin g th e tw o notice s discusse dabov e withi n 1 8 month s o f receiving acomplet e petition

. EP A will no t

accep t additiona l petition s o n th e sam e substanc e followin g publicatio n o

f afinal notic e o

f th e decisio n t o gran t

or den y apetitio n unles s ne w dat abecom e availabl e tha t coul dsignificantl y affec

t th e basi s fo

r th e decisio n mad e b y EPA

. I f significan t additiona l dat aar e available , intereste d person s may submi t

thes e dat athroug h th e petitio n procedure s identifie di n thi s notice

. Referenc e shoul db e mad e t o previou s petition s fo

r aspecifi c substance , identifyin g th e dat e Ui e petitio n wa s submitte dan dth e previou s petitioner

. Informatio n previousl y submitte dnee dno t

b e resubmitte dbu t may b e cite db y referenc e fo r reconsideration

. EP

A request s comment s o n th e propose dinformatio n t o b e require dfromth e petitione r an d th e propose dpetitio n process
. VI

. Discussio n ofth e Propose dRul e EP A i s proposin g t o ad dPar t 6 7 t o Titl e 4 0 o f th e Code o

f Federa l Regulations , whic hwoul dinclud e th e lis t o f regulate dsubstance s an d threshol dquantities , a s wel l a s th e requirement s fo

r th e petitio n proces s t o ad dregulate dsubstance s t o th e lis t o r t o delet e regulate dsubstance s fromth e list

. Propose d§ 68. 5 woul destablis hth e procedure s t o determin e whethe r a threshol dquantit y o

f aregulate d substanc e i s presen t

at astationary source
. Specifi c exemption s t o th e threshol ddeterminatio n procedur e ar e als o include dfo

r mixtur e concentrations , articles , an dcertai n use s an dactivities

. Propose d§68.10 0 woul destablis hth e purpos e o f th e subpar t

a s th e designatio n o f regulate dsubstance s an d thei r threshol dquantities , an d establishmen t

o f th e requirements fo

r petition s t o ad dsubstance s or delet e substance s fromUi

e list

. Propose d§ 68.12 0 woul dspecif y th e requirements fo

r petition s t o th e Agenc y t o ad dsubstance s t o th e list , an dt o delet e substance s fromth e list

. Propose d§ 68.12 5 woul dexemp t ammoniause da s an agricultura l nutrien t whe n hel db y afarmer

. Propose d§ 68.13 0 woul destablis hUi e lis t o f regulate dsubstances , includin g a lis t o f toxic substances , alis t

o f flammabl e substances , an dalis t criterio n fo

r commercia l hig h explosives

. Thi s sectio n als o woul d establis hUi

e threshol dquantitie s fo

r al l liste dsubstances

. VII

. Require dAnalyse s A. E.O. 12291 Unde r Executiv e Orde r

12291, th e Agenc y mus t

judg e whethe r

aregulation i s "major " an dthu s subjec t t o th e requirement

fo r aRegulator

y Impac t Analysi s (RIA)

. Unde r

E.O

. 12291 , a major rul e i s on e tha t

i s likel y t o resul t in : 1

. An advers e (cost) impac t i n th e econom y of

$10 0 million , 2

. A major

increas e i n cos t

o r price s t o consumers , individua l industries , Federal , state , o r

local government , or geographi c region , or 3

. Significan t

advers e effect s o n competition , employment , investment , productivity , innovation , o r th e ability o f U.S.-base denterprise s i n domesti c or export markets

. Base do n Ui

e RIA , EP A estimate s tha t approximatel y 140,50 0 facilitie s will b e covere db y th e thre e propose dhazard s list s an dthreshold s (i.e. , toxic , flammables, an dexplosives)

. Thes e facilitie s includ e 22,44 0 manufacturer s (18,96 0 o f who mar e covere db y th e OSH A rule) ; 33,25 0 publi c drinkin g wate r an dwast e treatmen t

system s (15,40 0 covere db y OSHA) ; 50,00 0 col d storag e facilitie s (42,50 0 covere db y OSHA) ; 4,46 0 wholesaler s (2,24 0 covere db y OSHA) ; 1,240 servic e industr y facilitie s (77 6 covere db y OSHA) ; 2,98 0 privat e utilitie s (3,00 0 covere db y OSHA) ; an d20,00 0 propan e retailers

. Th e averag e numbe r of regulate dsubstance s varie s fromon e pe r facilit y fo r col dstorag e facilities , t o 1 3 pe r facilit y fo r highl y comple x manufacturin g facilities

. EP A ha s determine dth e propose d rul e i s no t

amajor rul e fo r th e purpose s o f E.O

. 1229 1 becaus e th e list , b y itself , impose s n o cos t

o n facilities

. Th e cos t impac t of th e lis t an dthreshold s derive s fromcomplianc e wit hth e ris kP.2 0



### Federa l Registe r / Vol

. 58 , No

. 1 1 /Tuesday , Januar y 19 , 199 3 /

ProposedRule s 511 9

managemen t

regulation s an dothe r reasonabl e regulations , whic har e triggere db y th e presenc e o f aregulate d substanc e abov e it s threshol dquantity

. Becaus e Ui

e impac t o f Ui e lis t an d threshol ddecision s ar e felt throug hth e ris k managemen t

regulations , EP

A ha s prepare dacombine dpreliminar y RI A entitled , "Regulatory Impac t Analysi s i n Suppor t o f Listin g Regulate dSubstance s an dThreshold s an dMandatin g Ris k Managemen t

Program s fo

r Chemica l Acciden t Prevention , a s Require db y sectio n 112(r) o

f Ui e CAA, " whic h analyze s Ui

e impact s o

f variou s lis t

an d threshol doption s o n th e risk managemen t

requirements

. Th e RI

A i s availabl e i n th e docket

. Th e petitio n proces s i s th e onl y aspec t o f thi s rulemakin g tha t

i s directl y attribute dt o th e listin g o

f substances

. EP A estimate s tha t

th e petitio n proces s unde r thi s rulemakin g wil l cos t a facilit y submittin g apetitio n a n averag e o f $5,000

. EP

A estimate s tha t

ther e wil l b e 1 1 petition s ayear
. EP A anticipate s tha t th e cos t t o th e Federa l govemmen t fo r processin g an dreviewin g th e petition s wil l b e approximatel y equa l t o Ui e cos t t o facilitie s fo

r filing apetition

. Th e tota l annua l cos t

i s estimate dt o b e $110,00 0 ($5,00 0 x 2 x 1 1 petitions)

. B. Regulatory Flexibility Act I n accordanc e wit hth e Regulatory Flexibility Ac t

o f 1980 , Federa l agencie s mus t evaluat e th e effect s o

f th e rul e o n smal l entitie s an dexamin e alternative s Uia t may reduc e thes e effects

. Becaus e Ui e propose drule , b y itself

, ha s n o cos t impac t o n facilities , aseparat e Regulator y Flexibilit y analysi s wa s no t conducted , bu t

i s include di n th e combine dRIA , availabl e i n th e docket

. C Paperwork Reduction Act Th e informatio n collectio n requirement s i n thi s propose drul e hav e bee n submitte dfo

r approva l t o Ui

e Office o f Managemen t

an dBudge t (OMB ) unde r

Ui e Paperwork

Reductio n Act , 4 4 U.S.C

. 350 1 et

seq. An Informatio n Collectio n Reques t documen t ha s bee n prepare db y EP A (IC RNo

. 1601.1 ) an dacop y may b e obtaine dfromSand y Farmer , Informatio n Polic y Branch , EPA , 40 1 M St

. SW

. (PM-22Y) , Washington , DC 20460 , o r b y callin g (202 ) 260-2740

. Publi c reporting burde n fo r thi s collectio n of

informatio n i n th e petitio n process , Ui

e onl y aspec t

o f Ui e propose d rul e involvin g reporting o r recordkeeping, i s estimate dt o b e approximatel y 13 8 hours , includin g tim e fo r reviewing instructions , searchin g existin g dat asources , gatherin g an dmaintainin g dat aneeded , an dcompletin g an dreviewin g th e collectio n o f information

. EP

A estimate s tha t ther e wil l b e 1 1 petition s ayear
. Th e tota l annua l burde n i s estimate dt o b e 1,51 8 hour s (13 8 hour s x 1 1 petitions)

. Sen dcomment s regarding th e burde n estimat e o r

an y othe r aspec t o f thi s collectio n o

f informatio n t o Chief

, Informatio n Polic y Branch , PM-223Y , U.S

. EPA , 401 M St

. SW. , Washington , D C 20460 , an dth e Offic e ofinformatio n an dRegulator

y Affairs , Offic e o

f Managemen t

an dBudget , Washington , D C 20503 , Attn : Des k

Office r fo r EPA

. Th e final rul e wil l respondt o an y OM B or publi c comment s o n th e informatio n collectio n requirements containe di n thi s proposal

. Lis t o f Subject s i n 4 0 CF

RPar t 6 8 Chemicals , Hazardou s substances , Extremel y hazardou s substances , Intergovernmenta l relations , Clea n Ai r Act , Chemical acciden t

prevention

. Dated : Decembe

r 30,1992

. Willia mK

. Reilly , Administrator. Fo r th e reason s se t

ou t i n th e preamble , titl e 40 , chapte r I , subchapte r C o f th e Code o

f Federa l Regulation s i s propose dt o b e amende db y addin g a ne w par t 6 8 t o rea da s follows : PAR T68—CHEMICA L ACCIDEN T PREVENTIO N PROVISION S Subpar t A—Genera l Sec

. 68. 1 Scope

. 68. 3 Definitions

. 68. 5 Threshol ddetermination

. Subpar t B—Ris h Managemen

t Pla n Requirement

s [Reserved ] Subpar t C—Regulate

d Substance

s fo r Accidenta l Releas

e Preventio n 68.10 0 Purpose

. 68.12 0 Petitio n process
. 68.12 5 Exemptions

. 68.13 0 Lis t

o f substances

. Authority : 4 2 U.S.C

. 7412(r)

. Subpart A—Genera l §68. 1 Scops

. Thi s part set s fort hrequirement s fo

r chemica l acciden t

preventio n step s tha t mus t b e take n b y th e owne r

o r operato r o f stationar y sources
. §68. 3 Definitions

. Fo r Ui e purpose s ofthi s part : Accidental

release mean s a

n unanticipate demissio n o f aregulate d substanc e or

othe r extremel y hazardou s substanc e int o Ui

e ambien t ai r froma stationary source
. Administratormean s th e administrato r

o f th e U.S

. Environmenta l Protectio n Agency

. Article mean s amanufacture dite m tha t i s forme dt o aspecifi c shap e or desig n durin g manufacture , Uia t ha s en d us e function s dependen t

i n whol e or

i n part upo n th e shap e o r

desig n durin g en duse , an dUia

t doe s no t release o r otherwis e result

i n exposur e t o a regulatedsubstanc e unde r norma l condition s o

f processin g an duse
. CAS mean s th e Chemica l Abstract s Service

. Process mean s an y activit y involvin g aregulatedsubstanc e includin g an y use , storage , manufacturing , handling , o r onsit e movemen t

o f suc hsubstances , o r combinatio n of

thes e activities

. Fo r

th e purpose s o

f thi s definition , an y grou p o f vessel s tha t

ar e interconnected , o r separat e vessel s tha t

ar e locate dsuc h tha t aregulatedsubstanc e coul db e involve di n apotentia l release, shal l b e considere dasingl e process
. Regulated

substance i s an

y substance liste dunde r

sectio n 112(r)(3 ) ofth e Clean Ai r Ac t a s amended , an d§ 68.130

. Stationary source mean s an y buildings , structures , equipment , installations , o r

substanc e emittin g stationar y activitie s whic hbelon g t o th e sam e industria l group , whic har e locate do n on e o r

mor e contiguou s properties , whic har e unde r th e contro l o f th e sam e perso n (o r

person s unde r commo n control) , an dfromwhic han accidenta l release ma

y occur
. A stationar y sourc e include s transportatio n container s tha t ar e n o longe r unde r activ e shippin g order s an d transportatio n container s tha t ar e connecte dt o equipmen t

at th e stationar y sourc e fo

r th e purpose s o

f temporar y storage , loading , o r unloading

. Threshold

quantity mean s th e quantit y specifie dfo

r regulated substance s unde r

sectio n 112(r)(5 ) ofth e Clean Ai r Ac t a s amended , an dliste di n § 68.13 0 an ddetermine dt o b e presen t a t astationar y sourc e a s specifie di n §68.5

. Vessel mean s an y reactor , tank , drum , barrel , cylinder , vat , kettle , boiler , pipe , hose , or othe r container

. §68. 5 Threshol d dotormination

. (a ) A threshol dquantit y o

f aregulate d substanc e a s liste di n § 68.13 0 i s presen t at astationar y sourc e if

th e tota l quantit y of

Ui e regulatedsubstanc e containe di n aproces s exceed s th e threshold

. (b ) Fo r th e purpose s o

f determinin g whethe r mor e tha n athreshol dquantit y o f aregulate dsubstanc e i s presen t at th e stationar y source , Ui

e followin g exemption s apply : (1 ) Concentrations ofa regulated substance in a mixture. I f aregulated substanc e i s presen t

i n amixtur e an dT " ^ " P.2 1



### 512 0 Federa l Registe r/ Vol

. 58 ^ No

. 1 1 /

Tuesday , Januar y 19 , 199 3 / Propose dRule s
Ui e concentratio n ofth e substanc e i s belo w on e percen t

b y weigh t

ofth e mixture , th e amoun t

o f Uie substanc e i n Ui e mixtur e nee dno t

b e considere d whe n determinin g whethe r mor e tha n a threshol dquantit y i s presen t at th e stationary source
. (2) Articles. Regulate dsubstance s containe di n article s nee dno t b e considere dwhe n determinin g whethe r mor e tha n athreshol dquantit y i s presen t at th e stationar y source
. (3 ) Uses. Regulate dsubstance s use d fo r th e followin g purpose s nee dno t b e include dwhe n determinin g whethe r mor e tha n athreshol dquantit y i s presen t at th e stationar y source : (i ) Us e a s astructura l componen t o f th e stationary source ; (ii ) Us e o f product s fo

r routin e janitoria l maintenance ; (iii ) Us e b y employee s o

f foods , drags , cosmetics , or

othe r persona l item s containin g th e regulate dsubstance ; (iv ) Us e o f regulate dsubstance s presen t i n proces s wate r

or non-contac t coolin g wate r

a s draw n fromth e environmen t

or municipa l sources , or us e o f regulatedsubstance s presen t i n ai r use deithe r

a s compresse dai r

o r a s part o f combustion ; an d (v ) Us e solel y fo

r consumptio n a s fuel

. (4) Activities in Laboratories. I f a regulatedsubstanc e i s manufactured , processed , o r

use di n alaboratory at

a stationary sourc e unde r

th e supervisio n o f atechnicall y qualifie dindividua l a s define di n § 720.3(ee ) o

f thi s chapter , th e quantit y o

f Uie substanc e nee dno t b e considere di n determinin g whethe r a threshol dquantit y i s present

. Thi s exemptio n doe s no t

appl y to : (i) Specialt y chemica l production ; (ii ) Manufacture , processing , o r us e o f substance s i n pilo t

plan t scal e operations ; an d (iii ) Activitie s conducte doutsid e th e laboratory

. Subpart B—Ris k

Managemen t Pla n Requirement s [Reserved ] Subpart C—Regulate d Substance s fo r Accidenta l Releas e Preventio n §68.10 0 Purpose

. Thi s subpar t

designate s substance s t o b e liste dunde r

sectio n 112(r

) (3) , (4) , an d(5 ) ofth e Clea

n Ai r Act , a s amended , identifie s thei r threshol d quantities , an destablishe s Ui e requirement s fo

r petitionin g t o ad do r delet e substance s fromUi e list

. §681*2 0 Petitio n process .

(a ^ An y perso n ma

y petitio n Ui

e Administrato r

t o modify , b y additio n o r deletion , th e lis t

o f regulatedsubstance s identifie di n § 68.130

. Base do n th e informatio n presente db y th e petitioner , Ui e Administrato r

may gran t

or den y a petition

. (tt> ) A substanc e may b e adde dt o th e lis t if , i n th e cas e o

f an accidenta l release, i t i s know n t o caus e or

may b e reasonabl y anticipate dt o caus e death , injury , or seriou s advers e effect s t o huma n healt hor

th e environment

. ($) A substanc e ma

y b e delete dfro

m th e lis t if adequat e dat ao n Uie healt h an denvironmenta l effect s o f Ui e substanc e ar e availabl e t o determin e tha t Ui e substance , i n th e cas e o

f a n accidenta l release, wil l no t caus e death , injury , or seriou s advers e effect s t o huma n healt hor

th e environment

. (I ) N o substanc e fo

r whic hanationa l primary ambien t

ai r qualit y standar d ha s bee n establishe dshal l b e adde dt o th e list

. N o substanc e regulatedunde r titl e V I o f th e Clea n Ai r Act , a s amended , shal l b e adde dt o Ui e list

. (e ) Th e burde n o

f proo f i s o n th e petitione r t o demonstrat e tha t

Ui e criteri afo r additio n an ddeletio n ar e met

. A petitio n wil l b e denie dif thi s demonstratio n i s no t

made

. § ) Th e Administrato r

wil l no t accep t additiona l petition s o n th e sam e substanc e followin g publicatio n o f a final notic e o

f th e decisio n t o gran t

or den y apetition , unles s ne w dat abecom e availabl e tha t

coul dsignificantl y affect Ui e basi s fo r th e decision

. Jg ) Petition s t o modif

y th e lis t o f regulatedsubstance s mus t contai n th e following : fl ) Nam e an daddres s ofth e petitione r an dabrie f

descriptio n o

f th e organization(s ) fia t

th e petitione r represents , if

applicable ; P ) Name , address , an dtelephon e numbe r ofacontac t

perso n fo

r th e petition ; (3 ) Commo n chemica l name(s) , commo n synonym(s) , Chemica l Abstract s Servic e number , an dchemica l fonmul aan dstructure ; (4) Actio n requeste d(ad do r delet e a substance) ; (5 ) Rational e supportin g Uie petitioner' s position ; Uia

t is , ho w th e substanc e meet s th e criteri afo r additio n an ddeletion

. A short

summary ofth e rational e mus t

b e submitte dalon g wit h amor e detaile dnarrative ; an d (6) Supportin g data ; tha t is , th e petitio n mus t

includ e sufficien t informatio n t o scientificall y suppor t th e request t o modif y Ui e list

. Suc h informatio n shal l include : (i ) A lis t o f al l suppor t

documents ; (ii ) Documentatio n of

literatur e searche s conducted , including , bu t no t limite dto , identification o f Ui e database(s ) searched , Ui

e searc h strategy , date s covered , an dprinte d results; (iii ) Effects dat a(animal , human , an d environmenta l tes t

data ) indicatin g th e potentia l fo

r death , injury , o r

seriou s advers e huma n an denvironmenta l impact s fromacut e exposur e followin g an accidenta l release ; printe dcopies o f th e dat asources , i n English , shoul db e provided ; an d (iv ) Exposur e dat ao r

previou s acciden t histor y data , indicatin g Ui e potentia l fo

r seriou s advers e huma n healt ho r environmenta l effect s froma n accidenta l release

. Thes e dat amay include , bu t

ar e no t limite dto , physica l an dchemica l propertie s o f th e substance , suc ha s vapo r

pressure ; modelin g results , includin g dat aan d assumption s use dan dmode l documentation ; an dhistorica l acciden t data , citin g dat asources
. § 68.125 Exemptions

. Agricultural

nutrients. Ammoni ause d a s a n agricultura l nutrient , whe n hel d b y farmers , nee dno t

b e include dwhe n determinin g whethe r

athreshol d quantit y i s presen t

o n site

. §68.13 0 Us t o

f substances

. (a ) Explosive s ar e covere dunde r sectio n 112(r) ofth e Clean Ai r Ac t i f the y ar e classifie db y DO T i n Divisio n 1.1(4 9 CF Rpar t 172.102 ) define da s explosive s tha t

hav e amas s explosio n hazard , an dar e presen t

o n sit e i n quantitie s greate r

tha n 5,00 0 pounds

. (b ) Regulate dtoxi c an dflammabl e substance s unde r

sectio n 112(r

) ofth e Clean Ai r Ac t ar e th e substance s liste d i n Table s 1 , 2 , 3 , an d4 ofthi s section

. Threshol dquantitie s fo

r liste dtoxic an d flammabl e substance s ar e specifie di n th e tables

. (c ) Th e base s fo

r placin g toxi c an d flammabl e substance s o n th e lis t o f regulatedsubstance s ar e explaine di n th e note s t o th e list

.____22__



### Federa l Registe r

/ Vol

. 58 , No

. 1 1 /

Tuesday , January 19 , 199 3 / Propose dRule s 512 1

TABL E 1 T O §68.130.—LIS T O F REGULATE D TOXI C SUBSTANCE S AN D THRESHOL D QUANTITIE S FO R ACCIDENTA L RELEAS E

; , PREVENTIO N

[Alphabetica l Order—10 0 Substances]

Chemica l nam e CA S No

.

75-86- 5 107-02- 8 107-13- 1 814-68- 6 107-18- 6 107-11- 9 7664-41- 7 7664-41- 7 62-53- 3 7783-70- 2 7784-34- 1 7784-42- 1 98-87- 3 98-16- 8 98-07- 7 100-44- 7 140-29- 4 10294-34- 5 7637-07- 2 353-42- 4 7726-95- 6 75-15- 0 7782-50- 5 10049-04- 4 107-07- 3 67-66- 3 542-88- 1 107-30- 2 4170-30- 3 123-73- 9 506-77- 4 108-91- 8 19287-45- 7 110-57- 6 111-44- 4 75-78- 5 57-14- 7 2524-03- 0 106-89- 8 107-15- 3 151-56- 4 75-21- 8 7782-41- 4 50-00- 0 107-16- 4 110-00- 9 302-01- 2 7647-01- 0 74-90- 8 7647-01- 0 7664-39- 3 7722-84- 1 7783-07- 5 7783-06- 4 13463-40- 6 78-82- 0 108-23- 6 78-97- 7 126-98- 7 74-83- 9 74-87- 3 79-22- 1 60-34- 4 624-83- 9 74-93- 1 556-64- 9 75-79- 6 13463-3&- 3 7697-37- 2 10102-43- 9 98-95- 3 56-38- 2 79-21- 0 594-42- 3 108-95- 2 75-44- 5 7803-51- 2 10025-87- 3 Threshol d

quantit y (lbs)
5,00 0 1,00 0 10,00 0 1,00 0 5,00 0 1,00 0 1,00 0 5,00 0 5,00 0 1.00 0 5,00 0 50 0 1,00 0 1,00 0 50 0 1,00 0 1,00 0 1,00 0 1,00 0 5,00 0 1,00 0 10,00 0 1i00 0 50 0 100 0 10,00 0 50 0 1,00 0 10,00 0 10,00 0 1,00 0 5,00 0 50 0 1,00 0 10.00 0 1,00 0 5.00 0 1.00 0 10.00 0 10,00 0 1,00 0 5,00 0 50 0 50 0 5,00 0 1,00 0 5,00 0 5,00 0 50 0 1,00 0 50 0 5,00 0 50 0 1,00 0 50 0 10,00 0 5,00 0 5,00 0 1,00 0 5,00 0 10,00 0 1,00 0 5,00 0 1,00 0 1,00 0 10,00 0 1,00 0 50 0 5,00 0 1,00 0 10,00 0 1,00 0 1,00 0 1,00 0 10,00 0 50 0 1,00 0 1,00 0 Basi s lo r

listin g P ) P > C ) p ) P ) P ) (••" ) C--) P ) ( b ) P ) P ) P ) P ) ( b ) p) p ) p ) p ) p ) M P ) C-" ) P ) p ) p ) p ) p ) p ) p ) P ) p ) P ) p ) p ) P ) p ) P ) p ) p ) p ) P" ) p ) p ) p ) p ) p ) p ) 

## n C-" ) (..» ) p ) p ) (..t. ) P ) P ) P ) O P ) O O P ) P ) P" ) P ) P ) P ) P ) P ) P ) (') O P ) tt O (..t. ) P ) P ) Aceton e cyanohydri n Acrolei n Acrylonitril e Acryly l chlorid e Ally l alcoho l Allylamin e Ammoni a (anhydrous ) Ammoni a (aqueou s solution , con e 20 % o r greater ) Anilin e Antimon y pentafluorid e Arsenou s trichlorid e Arsln e Benza l chlorid e Benzenamine , 3-(trifluoromethyl) - Benzotrichlorid e Benzy l chlorid e Benzy l cyanid e Boro n trichlorid e Boro n trifluorid e Boro n trifluorid e compoun d wit h methy l ethe r (1:1 ) Bromin e Carbo n disulfid e Chlorin e Chlorin e dioxid e Chloroethano l Chlorofor m Chloromethy l ethe r Chloromethy l methy l ethe r Crotonaldehyd e Crotonaldehyde , (E) - Cyanoge n chlorid e Cyclohexylamin e Diboran e Trans-1,4-dichlorobuten e Dichloroethy l ethe r Dimethyldichlorosilan e Dimethylhydrazin e Dimethy l phosphorochloridothioat e Epichlorohydri n Ethylenediamin e Ethyleneimin e Ethylen e oxid e Fluorin e Formaldehyd e Formaldehyd e cyanohydri n Fura n Hydrazin e Hydrochlori c aci d (solution , con e 25 % o r greater )

. Hydrocyani c aci d Hydroge n chlorid e (anhydrous ) Hydroge n fluorid e Hydroge n peroxid e (con e > 52% ) Hydroge n selenid e Hydroge n sulfid e Iron , pentacarbonyl Isobutyronitril e Isopropy l chlorolormat e Lactonitril e Methacrylonitril e Methy l bromid e Methy l chlorid e Methy l chlorolormat e Methy l hydrazin e Methy l isocyanat e Methy l mercapta n Methy l thiocyanat e Methyltrichlorosilan e Nicke l carbony l Nitri c aci d Nitri c oxid e Nitrobenzen e Parathio n Peraceti c aci d Perchloromethylmercapta n Pheno l (liquid ) Phosgen e Phosphin e Phosphoru s oxychlorid eP.2 3



### 512 2 Federal Register/ Vol

. 58 , No

. 1 1 /

Tuesday , January 19 , 199 3 / Propose dRule s

TABL E 1 T O §68.130.—LIS T O F f.@suLAT.tfe > TOXI C SUBSTANCE S AN D THRESHOL D QUANTITIE S FO R ACCIDENTA L RELEAS E

PREVENTION—Continue d [Alphabetica l Order—10 0 Substances]
Chemica l nam e CA S No

. Threshol d quantit y (lbs) Basi s fo r

listin g Phosphoru s trichlorid e 7719-12- 2 5,00 0 p ) Plperidln e 110-89- 4 5,00 0 p ) Proplonltril e 107-12- 0 1,00 0 p ) Propy l chloroformat

e 109-61- 5 5,00 0 ( b) Propylenelmln e 75-55- 8 10,00 0 p ) Propylen e oxid e 75-56- 9 10,00 0 ( b) Pyridine , 2-methyl-5-vlnyl - 140-76- 1 1,00 0 (" ) Sulfu r dioxid e 7446-09- 5 1,00 0 (•• b ) Sulfuri c aci d 7664-93- 9 5,00 0 (« ) Sullu r tetralluorid e 7783-60- 0 1,00 0 (» ) Sullu r trioxid e 7446-11- 9 1,00 0 (•• b ) Tetramethyllea d 75-74- 1 1,00 0 (" ) Tetranitromethan e 509-14- 8 1,00 0 p ) Thlopheno l 108-98- 5 1,00 0 (" ) Titaniu m tetrachlorid e 7550-45- 0 50 0 (" ) Toluen e 2,4-dllsocyanate 584-84- 9 1,00 0 (• ) Toluen e 2,6-diisocyanate 91-08- 7 1,00 0 (• ) Toluen e diisocyanat

e (unspecified Isomer

) 26471-62- 5 1,00 0 (• ) Trichloroethylsllan e 115-21- 9 1,00 0 (" ) Trimethylchlorosilan e 75-77- 4 1,00 0 ( b) Viny l acetate monome r 108-05- 4 5,00 0 ( b) Viny l chlorid e 75-01- 4 10,00 0 (• ) Basi s lo r Listing : 'Mandate d lo r listin g b y Congress

. bO n EH S list , vapo r pressur e O. S mmH g o r greater
. 'O n EH S list , vapo r pressur e les s tha n 0. 5 mmHg , bu t ha s bee n Involve d I n accident

s resultin g I n deat h o r injury

. ' Toxi c gas. * Liste d base d o n toxicit y o t hydroge n chloride , potentia l t o releas e hydroge n chloride , an d histor y o f accidents

. TABL E 2 T O §68.130.—LIS T O F REGULATE D TOXI C SUBSTANCE S AN D THRESHOL D QUANTITIE S FO R ACCIDENTA L RELEAS E PREVENTIO N [CA S Numbe r Order—10 0 Substances]
CAS No

. Chemica l nam e Threshol d quantit y (lbs) Basi s lo r

listin g
50-00- 0

. 56-38- 2

. 57-14- 7
. 60-34- 4

. 62-53- 3

. 67-66- 3

. 74-83- 9

. 74-87- 3

. 74-90- 8

. 74-93- 1

. 75-01- 4

. 75-15- 0

. 75-21- 8

. 75-44- 5

. 75-55- 8 , 75-56- 9

. 75-74- 1 , 75-77- 4 , 75-78- 5 , 75-79- 6 , 75-86- 5

. 78-82- 0

. 78-97- 7
. 79-21- 0 , 79-22- 1 , 91-08- 7 , 98-07- 7 , 98-16- 8 , 98-87- 3

. 98-95- 3

. 100-44- 7 106-89- 8 107-02- 8 107-07- 3 107-11- 9 107-12- 0 107-13- 1 107-15- 3 107-16- 4 107-18- 6 107-30- 2 Formaldehyd e

Parathio n Dimethylhydrazin e Methy l hydrazin e Anilin e Chlorofor m Methy l bromid e Methy l chlorid e Hydrocyani c aci d Methy l mercapta n Viny l chlorid e Carbo n disulfid e Ethylen e oxid e Phosgen e Propyleneimin e Propylen e oxid e Tetramethyllea d Trimethytchloros i lan e Dimethyldlchloros l lan e Methyttrlchloros l lan e Aceton e cyanohydri n Isobutyronltril e Lactonltrll e Peraceti c aci d Methy l chloroformat

e Toluen e 2,6-diisocyanate Benzotrichlorid e Benzenamlne , 3-(trlfluoromethyl ) Benza l chlorid e Nitrobenzen e Benzy l chlorid e Epichlorohydri n Acrolei n Chloroethano l Allylamln e Propionitril e Acrylonitril e Ethylenediamin e Formaldehyd e cyanohydri n Ally l alcoho l Chloromethy l methy l ethe r 50 0 00 0 00 0 00 0 00 0 ,00 0 ,00 0 ,00 0 50 0 00 0 00 0 00 0 00 0 50 0 ,00 0 ,00 0 00 0 00 0 00 0 00 0 00 0 00 0 00 0 ,00 0 ,00 0 ,00 0 50 0 ,00 0 ,00 0 ,00 0 ,00 0 ,00 0 ,00 0 ,00 0 ,00 0 00 0 00 0 00 0 ,00 0 00 0 00 0 p ) p ) p ) p ) p ) p ) p ) (• ) P b ) p ) p ) p ) (-" ) p" ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p ) p )P.2 4



### Federa l Register/

Vol

. 58 , No

. 1 1 /

Tuesday , Januar

y 19 , 199 3 /

Propose dRule s 512 3

TABL E 2 T O §68.130.—LIS T O F REGULATE D TOXI C SUBSTANCE S AN D THRESHOL D QUANTITIE S FO R ACCIDENTA L RELEAS E PREVENTION—Continue d [CA S Numbe r Order—10 0 Substances]
CA S No

. Chemica l nam e Threshol d quantit y (lbs) 5,00 0 5,00 0 5,00 0 10,00 0 1,00 0 5,00 0 1,00 0 1,00 0 5,00 0 10,00 0 1,00 0 10,00 0 1,00 0 1,00 0 1,00 0 1,00 0 5,00 0 5,00 0 1,00 0 1,00 0 50 0 10,00 0 1,00 0 1,00 0 1,00 0 1,00 0 1,00 0 10,00 0 1,00 0 1,00 0 50 0 1,00 0 1,00 0 5,00 0 50 0 1,00 0 5,00 0 5,00 0 5,00 0 5,00 0 5,00 0 1,00 0 50 0 1,00 0 1,00 0 50 0 1,00 0 1,00 0 5,00 0 50 0 1,00 0 1,00 0 50 0 1,00 0 1,00 0 50 0 50 0 50 0 1,00 0 Basi s fo r

listin g P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) C ) P ) P" ) P ) P ) P ) P" ) pt. ) P ) P ) P" ) P ) (••" ) P b ) P" ) P ) P ) P ) P ) P" ) P ) P b ) P b ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) P ) 108-05- 4

... . 108-23- 6

... . 108-91- 8

... . 108-95- 2

... . 108-98- 5 109-61- 5 110-00- 9 110-57- 6

... . 110-89- 4

... . 111-44- 4

... . 115-21- 9

... . 123-73- 9

... . 126-98- 7
... . 140-29- 4

... . 140-76- 1

... . 151-56- 4

... . 302-01- 2

... . 353-42- 4

... . 506-77- 4

... . 509-14- 8

... . 542-88- 1

... . 556-64- 9

... . 584-84- 9

... . 594-42- 3

... . 624-83- 9

... . 814-68- 6

... . 2524-03- 0

. . 4170-30- 3

. . 7446-09- 5

. . 7446-11- 9

. . 7550-45- 0

. . 7637-07- 2

. . 7647-01- 0

. . 7647-01- 0

. . 7664-39- 3

. . 7664-41- 7
. . 7664-41- 7
. . 7664-93- 9

. . 7697-37- 2

. . 7719-12- 2

. . 7722-84- 1

. . 7726-95- 6

. . 7782-41- 4

. . 7782-50- 5

. . 7783-06- 4

. . 7783-07- 5

. . 7783-60- 0

. . 7783-70- 2

. . 7784-34- 1

. . 7784-42- 1

. . 7803-51- 2

. . 10025-87- 3 10049-04- 4 10102-43- 9 10294-34- 5 13463-39- 3 13463-40- 6 19287-45- 7 26471-62- 5 Viny l acetate monome r

Isopropy l chloroformat

e Cyclohexylamin e Pheno l (liquid ) Thlopheno l Propy l chloroformat

e Fura n Trans-1,4-dichlorobuten e Piperidin e Dichloroethy l ethe r Trichloroethyls i lan e Crotonaldehyde , (E ) Methacrylonitril e Benzy l cyanid e Pyridine , 2-methyl-5-vlny l Ethyleneimin e Hydrazin e Boro n trifluorid e compoun d wit h methy l ethe r (1:1 )

. Cyanoge n chlorid e Tetranitromethan e Chloromethy l ethe r Methy l thiocyanat

e Toluen e 2,4-diisocyanate Perch - loromethylmer

- capta n Methy l isocyanat

e Acrytyl chlorid e Dimethylphosphorochloridothloat e Crotonaldehyd e Sulfu r dioxid e Sulfu r trioxid e Titaniu m tetrachlorid e Boro n trifluorid e Hydroge n chlorid e (anhydrous ) Hydrochlori c aci d (solution , con e 25 % o r greater )

.. . Hydroge n fluorid e Ammoni a (anhydrous) Ammoni a (aqueou s solution , con e 20 % o r greater)

. Sulfuri c aci d Nitri c aci d Phosphoru s trichlorid e Hydroge n peroxid e (con e > 52% ) Bromin e Fluorin e Chlorin e Hydroge n sulfid e Hydroge n selenid e Sulfu r tetrafluorid e Antimony pentafluorid e Arsenou s trichlorid e Arsln e Phosphin e Phosphoru s oxychlorid e Chlorin e dioxid e Nitri c oxid e Boro n trichlorid e Nicke l carbony l Iron , pentacarbony l Diboran e Toluen e diisocyanat

e (unspecified Isomer

) Basi s to r Listing : " Mandate d fo r listin g b y Congress

. b O n EH S list , vapo r pressur e O. S mmH g o r greater
. •O n EH S list , vapo r pressur e les s tha n O. S mmHg , bu t ha s bee n Involve d In accident

s resultin g In deat h o r Injury

. * Toxi c gas. •Liste d base d o n toxicit y o l hydroge

n chloride , potentia l t o releas e hydroge n chloride , an d histor y o f accidents

. TABL E 3 T O §68.130.

- -LIS T O F REGULATE D FLAMMABL E SUBSTANCE S AN D THRESHOL D QUANTITIE S FO R ACCIDENTA L RELEAS E PREVENTIO N [Alphabetica l Order—6 2 Substances]
Chemica l nam e CA S No

. Threshol d quantit y (lbs ) Basi s fo r

listin g Acetaldehyd e Acetylen e Bromotri - fluorethylen e 1,3-Butadlen e 75-07- 0 74-86- 2 598-73- 2 106-99- 0 10,00 0

10,00 0 10,00 0 10,00 0•I ppi " 

### " T P.2 5



### 512 4 Federa l Registe r / Vol

. 5 ^ No

. 1 1 /

Tuesday , January 19 , 199 3 / Propose dRule s

TABL E 3 T O §68.130.^LIS T © F REGULATE D FLAMMABL E SUBSTANCE S AN D THRESHOL D QUANTITIE S FO R ACCIDENTA L RELEAS E PREVENTION—Continue d [Alphabetica l Order—6 2 Substances]
Chemica l nam e CA S No

. Threshol d quantit y (lbs) Basi s fo r

listin g
Butan e 106-97- 8 10,00 0 1-Buten e 106-98- 9 10,00 0 2-Buten e 107-01- 7 10.00 0 Buten e 25167-67- 3 10,00 0 ft 2-Butene-cl s 590-18- 1 10,00 0 2-Butene-tran s 624-64- 6 10,00 0 ft Carbo n oxysulfid e 463-58- 1 10,00 0 Chlorin e monoxid e 7791-21- 1 10,00 0 2-Chloropropylen e 557-98- 2 10,00 0 1-Chloropropylen e 590-21- 6 10,00 0 Cyanoge n 460-19- 5 10,00 0 ft Cyclopropan e 75-19- 4 10,00 0 ft Dlchlorosilan e 4109-96- O 10,00 0 ft Difluoroethan e 75-37- 6 10,00 0 ft Dimethylamin e 124-40- 3 10,00 0 2,2-Dlmethylpropan e 463-82- 1 10,00 0 Ethan e 74-84- 0 10,00 0 ft Ethy l acetylen e 107-00- 6 10,00 0 ft Ethylamln e 75-04- 7 10,00 0 ft Ethy l chlorid e 75-00- 3 10,00 0 ft Ethylen e 74-85- 1 10,00 0 Ethy l ethe r 60-29- 7 10,00 0 Ethy l mercapta n 75-08- 1 10,00 0 Ethy l nitrit

e 109-95- 5 10,00 0 ft Hydroge n 1333-74- 0 10,00 0 ft Isobutan e 75-28- 5 10,00 0 Isopentan e 78-78- 4 10,00 0 Isopren e 78-79-,' i 10,00 0 Isopropylamin e 75-31- 0 10,00 0 Isopropylchlorid e 75-29- 6 10,00 0 Methan e 74-82- 8 10,00 0 ft Methylamin e 74-89- 5 10,00 0 ft 3-Methyl-1-buten e 563-45- 1 10,00 0 2-Methyl-1-buten e 563-46- 2 10,00 0 Methy l ethe r 115-10- 6 10,00 0 Methy l format

e 107-31- 3 10,00 0 2-Methylpropen e 115-11- 7 10,00 0 ft 1,3-Pentadien e 504-60- 9 10,00 0 ft Pentan e 109-66- O 10,00 0 1-Penten e 109-67- 1 10,00 0 2-Pentene , (E) - 646-04- 8 10,00 0 2-Pentene , (Z) - 627-20- 3 10,00 0 Propadien e 463-49- 0 10,00 0 ft Propan e 74-98- « 10,00 0 ft Propylen e 115-07- 1 10,00 0 ft Propyn e 74-99- 7 10,00 0 ft Silan e 7803-62- 5 10,00 0 ft Tetrafluoroethylen e 116-14- 3 10,00 0 ft Tetramethylsllan e 75-76- 3 10,00 0 Trichlorosilan e 10025-78- 2 10,00 0 Trifluoro- chloroethylen e 79-38- 9 10,00 0 ft Trimethylamin e 75-50- 3 10,00 0 ft Viny l acetylen e 689-97- 4 10,00 0 ft Viny l ethy l ethe r 109-92- 2 10,00 0 (•) Viny l fluorid e 75-02- 5 10,00 0 Vinyliden e chlorid e 75-35- 4 10,00 0 Vinyliden e fluorid e 75-38- 7 10,00 0 ft Viny l methy l ethe r 107-25- 5 10,00 0 ft
Basi s to r Listing : 'Flammabl e gas . •Volatil e flammabl e liquid

. TABL E 4 T O §68.130.—LIS T O F REGULATE D FLAMMABL E SUBSTANCE S AN D THRESHOL D QUANTITIE S FO R ACCIDENTIA L RELEAS E PREVENTIO N [CA S Numbe r Order—6 2 Substances ]
CAS No

. Chemica l nam e Threshol d quantit y (lbs) Basi s fo r

listin g
60-29- 7 74-82- 8 74-84- 0 74-85- 1 74-86- 2 74-89- 5 74-98- 6 Ethy l ether..

.

Methan e Ethan e Ethylen e Acetylen e ... . Methylamin e Propan e 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0P.2 6



### Federa l Registe r

/ Vol

. 58 , No

. 1 1 /

Tuesday , January 19 , 199 3 / Propose dRule s 512 5

TABL E 4 T O §68.130.

- -LIS T O F REGULATE D FLAMMABL E SUBSTANCE S AN D THRESHOL D QUANTITIE S FO R ACCIDENTIA L RELEAS E PREVENTION—Continue d [CA S Numbe r Order—6 2 Substances]
CAS NO

. Chemica l nam e Threshol d quantit y (lbs) Basi s fo r

listin g 74-99- 7 75-00- 3 75-02- 5 75-04- 7 75-07- 0 75-08- 1 75-19- 4 75-28- 5 75-29- 6 75-31- 0 75-35- 4 75-37- 6 75-38- 7 75-50- 3 75-76- 3 78-78-^ 1 78-79- 5 79-38- 9 106-97- 8

... . 106-98- 9

... . 106-99- 0

... . 107-00- 6

... . 107-01- 7
... . 107-25- 5

... . 107-31- 3

... . 109-66- 0

... . 109-67- 1

... . 109-92- 2

... . 109-95- 5

... . 115-07- 1

... . 115-10- 6

... . 115-11- 7
... . 116-14- 3

... . 124-40- 3

... . 460-19- 5

... . 463-49- 0

... . 463-58- 1

... . 463-82- 1

... . 504-60- 9

... . 557-98- 2

... . 563-45- 1

... . 563-46- 2

... . 590-18- 1

... . 590-21- 6

... . 598-73- 2

... . 624-64- 6

... . 627-20- 3

... . 646-04- 8

... . 689-97- 4

... . 1333-74- 0

. . 4109-96- O

. . 7791-21- 1

. . 7803-62- 5

. . 10025-78- 2 25167-67- 3 Propyn e

Ethy l chlorid e Viny l fluorid e Ethylamin e Acetaldehyd e Ethy l mercapta n Cyclopropan e Isobutan e Isopropy l chlorid e Isopropylamin e Vinyliden e chlorid e Difluoroethan e Vinyliden e fluorid e Trimethylamin e Tetramethylsilan e Isopentan e Isopren e Trifluorochloroethylen e Butan e 1-Buten e 1,3-Butadien e Ethy l acetylen e 2-Buten e Viny l methy l ethe r Methy l format

e Pentan e 1-Penten e Viny l ethy l ethe r Ethy l nitrit

e Propylen e Methy l ethe r 2-Methylpropen e Tetrafluoroethylen e Dimethylamin e Cyanoge n Propadien e Carbo n oxysulfid e 2,2-Dlmethylpropan e ... . 1,3-Pentadien e 2-Chloropropylen e 3-Methyl- l -buten e 2-Methyl-1-buten e 2-Butene-ci s 1-Chloropropylen e Bromotrifluorethylen e .. . 2-Butene-tran s 2-Pentene , (Z ) 2-Pentene , (E ) Viny l acetylen e Hydroge n Dichlorosilan e Chlorin e monoxid e Silan e Trichlorosilan e Buten e 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0 10,00 0

Basi s fo r Listing : 'Flammabl e gas. 'Volatil e flammabl

e liquid

.
[F RDoc . 93-96 0 File d 1-15-93 ; 8:4 5 am ] BILUN Q COD

E 6560-50- M