# OAR Box 1833

Prepped by Keeia Richards



### Document

Number: 

# 97 ) l-A-4

Docket Number: 

# A-88-0 2

Printed 11/14/2008 11:01:30 AM Sheet 97 of 172 P. 1

### P. 2



## A-88-0 2

Th e informatio n o n healt h o r ris k assessmen t i n thi s repor t wa s compile d befor e th e Clea n Ai r Ac t Amendment s (1990 ) bu t wa s no t use d i n th e developmen t o f th e Chromiu mNESHAP
.



## H @ B ( 1 Wl i J l J * I 8(99 1
EP A AI R DOCKE T |P. 3



## A-88-0 2 X-R- M

CHROMIU M EMISSION S FRO

M CHROMIUM

ELECTROPLATINGOPERATIONS TECHNICA L REPOR T

Emissio nStandar dDivisio n

U.S . Environmenta l Protectio nAgenc y Offic e o f Ai r an

dRadiatio n Offic e o f Ai r Qualit y

Plannin g an

dStandard s Researc hTriangl e Park , Nort hCarolin a 2771 1

Novembe r 198 5P. 4

TITL E O F CONTENT S

Pag e
LIS T O F TABLES. . i i
A . Definitio no f Sourc e Categor y 1
1 . Plant s inoperatio nan dprocesse s 1
2 . Projection s o f industr y growt h2
B . Emission s andContro l 4
C . Potentia l fo r ImprovedContro l 7
D . Ris k Assessmen t Input s 9

1 . Annua l incidenc e 9 2 . Maximu

m individua l ris k 1 1 E . Reference s 1 4

LIS T O F TABLE S

Tabl e 1 . Range s o f Operatin g Parameter s fo r Har dan dDecorativ e Chromiu m Platin g Operation s Tabl e 2 . Uncontrolle dEmissio nFactor s Use dt o Estimat e

Emission s fro

m Chromiu m Electroplatin g Operation s Tabl e 3 . Emissio nReduction s an dAnnualize dCos t o f Contro l fo r Fou r Mode l Chromiu

m Electroplatin g Operation s Tabl e 4 . Ris k Assessmen t Input s fo r Calculatin g Annua l

Incidenc e Du e t o Hexavalen t Chromiu m Emission s fro

m th e Chromiu

m Electroplatin g Sourc e Categor y Tabl e 5 . Ris k Assessmen t Input s fo r Calculatin g Maximu m Lifetim e Ris k Du e t o Hexavalen t Chromiu m Emission s from th e Chromiu

m Electroplatin g Sourc e Categor y Tabl e 6 . Risk s Associate dwit hExposur e t o Uncontrolle d

Hexavalen t Chromiu

m Emission s From

Mode l Chromiu

m Electroplatin g Operation s Pag e

3

5

8

1 0

1 2

1 3



### nP. 5

TECHNICA L REPORT : CHROMIUM ELECTROPLATING

A . Definitio no f Sourc e Categor y Th e chromiu

m electroplatin g sourc e categor y comprise s two distinc t type s o f platin g operations : "hard " an d"decorative. " I nhar dplating , a relativel y

thic k laye r o f chromiu m i s deposite ddirectl y t o th e bas e materia l (usuall y

steel ) t o provid e wea r resistance , lo w coefficien t o f friction , hardness , an dcorrosio nresistanc e o r t o buil dupsurface s tha t hav e bee nerode db

y use . Har dplatin g i s use dfo r item s suc ha s hydrauli c cylinder s an

drods , industria l rolls , zin c di e castings , plasti c molds , engin e components , andmarin e hardware . I ndecorativ e plating , th e bas e materia l (e.g. , brass , steel , aluminum , o r plastic ) i s generall y plate d wit ha laye r o f nicke l followe db y a relativel y

thi nlaye r o f chromiu m t o provid e a bright , tarnish-resistan t surface . Decorativ e platin g i s use d fo r item s suc ha s automotiv e trim , meta l furniture , bicycles , handtools , an dplumbin g fixtures . Althoug hothe r type s o f operation s performe da t electroplatin g plant s involv e chromiu m insome form , thi s sourc e categor y include s onl y

thos e processe s tha t us e chromi c aci di nanelectrolyti c cel l t o deposi t chromium meta l o na product . 1 . Plant s i noperatio nan dprocesses . Ther e ar e abou t 9,70 0 chromiu m electroplatin g operation s i nth e country . Chromiu m electroplatin g i s use di nth e manufactur e o f a wid e variet y o f industria l an

dconsume r items . Ingeneral , chromium platin g operation s ar e locate da t o r nea r the industrie s the y

service , whic har e usuall y i ncenter s o f hig hpopulatio n density . Platin g operation s rang e insiz e fro m smal l shop s operatin g on e 400-gallo ntan k fo r a s fe w a s 1 5 hour s pe r wee k t o larg e shop s operatin g fiv e 17,000-gallo ntank s fo r a s many a s 13 0 hour s pe r week . Mos t platin g operation s ar e "captive " processe s performe dwithi nlarge r manufacturin g facilities . Some operation s ar e "jobshops " tha t provid e custom platin g service s fo r man y

differen t clients . Captiv e plater s an djobshop s ma y perfor m eithe r har do r decorativ e platin g o r both . Th e actua l chromiu

m platin g proces s i s simila r fo r har dan ddecorativ e platin g althoug hpretreatmen t processe s an doperatin g parameter s ma yP. 6

diffe r somewhat . Th e platin g proces s involve s placin g th e ite m t o be plate d i na tank containin g chromi c aci d solutio nan d a smal l amoun t o f sulfuri c aci d a s a catalyst . Direc t electrica l curren t i s passe d fro m a n anod e (positiv e electrode ) throug hth e platin g solution . Thi s result s i n chromiu m depositin g ou t o f solutio nont o th e workpiece , whic hi s th e cathod e (negativ e electrode) . (I nth e cas e o f platin g a plastic , th e pretreatmen t proces s include s step s t o rende r th e surfac e conductiv e prio r t o plating. ) Typica l operatin g parameter s fo r bot hhar d an d decorativ e platin g ar e show

ninTabl e 1 . Th e chromiu

m platin g proces s i s ver y inefficient . Onl y

1 0 t o 2 0 percen t o f th e powe r applie d i s use d t o deposi t chromiu m ont o th e workpiece . Th e balanc e i s consume d b y th e generatio no f hydroge nga s a t th e surfac e o f th e cathodes . Platin g efficienc y ca nb e improve d i nsom e situation s b

y adding fluorid e t o th e platin g solution . However , fluorid e canno t b e use d inal l type s o f platin g solution s an d ma y caus e "etching "
o r "burning " o f expose d stee l surface s i f use d inhar d platin g solutions . 2 . Projection s o f industr y growth . Chromiu

m electroplatin g i s no t a distinc t industry ; i t i s a proces s performe d withi nan d fo r a wid e variet y o f industries . Thus , th e growt ho f chromiu m electroplatin g operation s i s determine d b

y trend s i nth e industr y sector s tha t requir e thes e services . Althoug hnew

electroplatin g operation s ma y be buil t t o accommodat e growt h inspecifi c industrie s o r t o replac e obsolet e o r relocate d equipment , n o
ne t increas e i nth e us e o f chromiu m electroplatin g i s expected . Th e followin g consideration s form th e base s fo r thi s conclusion : (1 ) chromi c aci d consumptio nb

y meta l plater s ha s remaine d relativel y constan t ove r th e pas t 1 0 years , an d (2 ) th e deman d fo r decorativ e platin g i nth e automobil e industry

(one o f th e larges t consumer s o f chromi c aci d fo r meta l plating ) ha s decrease d becaus e o f th e us e o f substitut e material s fo r bumper s an

dtrim .TABL E 1 . RANGE S OF OPERATINGPARAMETER S FOR,HARD AN D DECORATIVE CHROMIU

M PLATINGOPERATION S ' P. 7

Hard platin g Decorativ e platin g
Platin g thickness , y m (mil )

Platin g time , mi n Chromi c aci d concentration , g/ a (oz/gal ) 1. 3 t o 76 2 (0.0 5 t o 30 )
2 0 t o 6,00 0
22 5 t o 37 5 (3 0 t o 50 ) 0.0 3 t o 2. 5 (0.00 1 t o 0.1 ) 0. 5 t o 5
22 5 t o 37 5 (3 0 t o 50 )

Temperatur e o f solution , ° C (°F )
Voltage , volt s

Current , ampere s 4 9 t o 6 6 (12 0 t o 150 ) 3 8 t o 4 6 (10 0 t o 115 ) (Depend s o

nth e distanc e betwee n th e anode s an

d th e items being plated. ) (Depend s o

nthe amoun t o f surfac e are a being plated. )
Curren t density , amperes/m ' (amperes/f t ) 1,60 0 t o 6,50 0 (15 0 t o 600 ) 54 0 t o 2,20 0 (5 0 t o 200 )P. 8

B . Emission s an

dControl s Hexavalen t chromiu

m i s emitte ddurin g th e chromiu m electroplatin g proces s i nth e form

o f a visibl e yello w mist . Th e mis t i s compose do f entraine dchromi c aci ddroplet s tha t form whe nth e hydroge nan doxyge nga s i s release dfrom

th e surfac e o f th e platin g solution . Th e hydroge nga s i s generate da t th e cathod e whil e oxyge ni s liberate da t th e anode . Factor s affectin g th e amoun t o f mis t generate dfro m platin g tank s includ e th e amoun t o f curren t applied , th e amoun t o f surfac e are a plated , the amoun t o f chromium deposited , th e duratio no f plating , an dth e surfac e
are a o f th e tank . Uncontrolle demissio nfactor s tha t ca nbe applie dt o chromi c aci dconsumptio nhav e bee ndevelope db y EPA fo r bot hhardan

d decorativ e platin g an dar e presente di nTabl e 2 . Th e factor s ar e base do n result s o f EP A

sourc e test s a t on e har dplatin g facilit y an don e decorativ e platin g facility . Th e platin g operation s teste dwer e representativ e o f a larg e jobsho p performin g har dchromiu m platin g o f industria l roll s an da larg e captiv e sho pperformin g decorativ e chromiu m platin g o f automobil e bumpers . Althoug hthes e two operation s d o no t characteriz e th e chromiu m electroplatin g sourc e categor y i never y

respect , the y

ar e representativ e
o f othe r platin g operation s interm s o f th e processe s an dtype s o f emissio ncontrols . Th e emissio ncaptur e system s a t bot hplant s wer e effectiv e i nwithdrawin g mis t fro m th e platin g area . Th e decorativ e plating tan k containe da fume suppressan t t o inhibi t misting , whic hi s commonpractic e fo r abou t 9 0 percen t o f decorativ e platin g operations . Emission s from

bot hplatin g operation s wer e controlle db y multipl e packed-be dscrubbers . ' Ther e ar e severa l method s use dt o reduc e chromiu m emission s fro

m chromiu m electroplatin g operations . On e metho duse db y many decorativ e plater s involve s addin g chemica l fume suppressant s t o th e platin g solution . Althoug hther e ar e differen t types , mos t fume suppressant s generall y

contai na surfactan t tha t reduce s th e surfac e tensio no f th e platin g solution . Thus , th e hydroge nan doxyge ngase s ar e release d withou t formin g th e chromi c aci dbubble s tha t caus e misting . I naddition ,V P. 9

TABL E 2 . UNCONTROLLE D EMISSION FACTOR S USE D T O ESTIMATE EMISSION S FRO M CHROMIU

M ELECTROPLATINGOPERATION S

Typ e o f operatio n Emissio nfactor ,

k g Cr + V k g Cr0 3 use d Basi s

Hard

Decorativ e 0.009 4

0.00024 a EP A sourc e tes t a t Carolin a Plating—Rol l Divisio nplan t in Greenville , Sout hCarolina . EP A sourc e tes t a t C . S . Oh m Manufacturin g Company plan t in Sterlin g Heights , Michigan .
'Base d onth e assumptio ntha t th e fum e suppressan t use d durin g th e tes t controlle d 8 0 percen t o f th e misting .P.1 0

som e fume suppressant s als o creat e a laye r o f foa m o nth e surfac e o f th e platin g solution , whic haid s i ninhibitin g misting . Chemica l manufacturer s stat e tha t prope r us e o f fume suppressant s appea r t o b e quit e effectiv e fo r reducin g misting , bu t ther e ar e n o tes t dat a availabl e t o substantiat e thi s claim. " Anothe r metho do f reducin g chromiu m emission s involve s th e applicatio n
o f exhaus t system s t o th e platin g tank s an dth e treatmen t o f th e resultan t exhaus t gase s b

y a contro l device . Tw o type s o f contro l device s ar e typicall y

used : impingement-typ e mis t eliminator s an dpacked-be dwe t scrubbers . Th e mis t eliminator s ar e equippe dwit hbaffle s tha t continuall y

chang e th e directio no f th e ga s flow . Thi s promote s th e impingemen t o f droplet s o f mis t entraine dinth e exhaus t ga s o nth e baffles . Th e collecte dmis t i s discharge deithe r int o a holdin g tank o r directl y bac k int o th e platin g tank . Contro l devic e vendor s estimat e
remova l efficiencie s t o b e 8 0 t o 8 5 percen t fo r impingemen t mis t eliminators . Tes t dat a provide db y th e Nava l Energ y

an dEnvironmenta l Suppor t Activit y

(NEESA ) Grou pindicat e tha t 9 6 percen t remova l efficienc y wa s bein g achieve db y a mis t eliminato r controllin g emission s a t th e Norfol k Nava l Shipyard . I npacked-be dscrubbers , th e exhaus t gase s ar e saturate dwit hwate r
an dthe npasse dthroug hon e o r mor e bed s o f packin g material , th e bed s ar e severa l inche s an

dupan dar e continuousl y

wette do r sprayed . Typically , th e scrubber s use di

nthi s sourc e categor y contai non e o r two packe d beds . Any

mis t o r fume entraine dinth e exhaus t ga s imping e o nth e packin g an

di s washe daway

b y th e scrubbin g liquid . Contro l devic e vendor s estimat e remova l efficiencie s t o be 9 5 t o 9 9 percen t fo r thes e devices. 1 Actua l EPA sourc e test s conducte dacros s a doubl e packed-be d scrubbe r controllin g emission s a t th e Carolin a Plating—Rol l Divisio n plan t indicate dtha t 9 5 percen t remova l efficienc y wa s bein g achieved . Tes t dat a provide db

y th e NEES A

Grou pindicat e tha t 9 2 percen t remova l efficienc y

wa s bein g achieve db y a singl e packed-be dscrubbe r controllin g emission s a t th e Lon

g Beac hNava l Shipyard .P.1 1

C . Potentia l fo r Improve dContro l Ther e appear s t o be significan t potentia l fo r improve dcontro l i nthi s sourc e category . Althoug hno statistica l dat a ar e available , i t i s estimate dtha t emission s fro m abou t 5 0 percen t o f the hardplater s an d abou t 1 0 percen t o f th e decorativ e plater s currentl y ar e uncon trolled . ' Informatio nobtaine dfro m almos t 6 0 plant s suppor t thi s assumption , whic hi s base do nestimate s fro m contro l devic e vendor s an d fume suppressan t manufacturers . Fume suppressant s ma y be use dt o reduc e hexavalen t chromiu m emission s fro m decorativ e platin g operation s tha t ar e currentl y uncontrolled . Th e achievabl e contro l efficienc y i s conservativel y

assume dt o b e 8 0 percent . Th e base s fo r thi s assumptio nwer e observation s a t severa l plants , whic h demonstrate dtha t typicall y fume suppressant s appea r t o be adde daccordin g t o th e operator' s discretio no r judgmen t rathe r tha na systemati c schedul e
o r plan . Althoug hfum e suppressant s als o ar e availabl e fo r us e i nhar d chromiu m platin g operations , hardplater s hav e cite dproblem s wit h electrica l sparkin g an d"pitted " surfac e finishe s whe nthes e chemical s ar e use di nth e platin g solutions . Add-o ncontro l device s ma y be use dt o reduc e hexavalen t chromium emission s fro

m eithe r hardo r decorativ e platin g operations . Th e captur e efficienc y

o f a well-designe d an d-operate dventilatio nsystem i s estimate dt o approac h10 0 percent . Achievabl e contro l efficiencie s ar e conservativel y

assume dt o be 8 5 percen t fo r impingemen t mis t eliminator s
an d9 5 percen t fo r packed-be dscrubbers . Estimate s o f cost s an demissio nreduction s ar e presente di nTabl e 3 fo r differen t type s o f emissio ncontrol s applie dt o eac ho f th e fou r mode l plant s use dt o estimat e maximu m lifetime risk s (se e Sectio nD-2) . Th e mode l plant s ar e representativ e o f different size s (smal l an dlarge ) an

d type s (hardan

ddecorative) . Althoug hth e emissio nreduction s achievabl e b y th e control s ma y

b e subjec t t o question , th e actua l value s ar e probabl y
n o lowe r tha nthos e liste d inTabl e 3 .P.1 2

TABL E 3

. EMISSIO NREDUCTION S AND ANNUALIZE D COS T O F CONTRO L FO R FOU R MODE L CHROMIUM ELECTROPLATIN G OPERATION S

Ite m Mode l plan t 

### B Typ e o f platin g operatio n Smal l har d Larg e

har d Smal l

decora

tiv e Larg e decora

tiv e Uncontrolle d emissio n factor , k g C r /k g Cr0 3 use d Cr0 3 consumption , kg/y r (lb/yr ) Uncontrolle d emissio n rate , k g Cr + / y r (l b Cr + /yr ) Packed-be d we t scrubber 3 0.009 4
82 0 (1,800 ) 7. 7 (17 ) 0.009 4

9,60 0 (21,200 ) 9 0 (200 ) 0.0002 4

1,10 0 (2,400 ) 0.2 6 (0.57 ) 0.0002 4

16,30 0 (35,900 ) 3. 9 (8.6 )

Achievabl e emissio n reduction , k g Cr +6 /y r (l b Cr + /yr i Capita l cos t o f control , $ Annualize d cos t o f control, 0 $/y r Impingemen t mis t eliminato r Achievabl e emissio n reduction , k g Cr + /y r (l b Cr + /yr) Capita l cos t o f control , $ Annualize d cos t o f control, 0 $/y r Chemica l fum e suppressan t Achievabl e emissio n reduction , k g Cr +5 /y r (l b Cr + /yr ) Capita l cos t o f control , $ Annualize d cos t o f control , $/y r 7. 3 (16 ) 10,50 0 4,52 0 8 6

(190 ) 35,40 0 15,30 0 0.2 5

(0.55 ) 10,50 0 4,38 0 3. 7

(8.2 ) 43,30 0 19,40 0



### 6. 5 (14 ) 2,69 0 

### 96 0 7 7

(170 ) 8,50 0 2,58 0 0.2 2

(0.49 ) 2,69 0 1,02 0 

### 3. 3

(7.3 ) 9,40 0 3,54 0



### N/ A N/ A N/ A N/

A N/ A N/ A 0.2 1

(0.46 ) 

### 0 1,83 0 

### 3. 1

(6.8 ) 

### 0 26,60 0
N/ A= no t applicable

. ^Packed-be d scrubbe r wit h tw o layer s o f packin g t o contro l emissions

. b Doe s no t includ e cos t o f connectin g existin g ventilatio n syste mt o contro l device

. c Doe s no t includ e cos t o f wastewate r treatment
.P.1 3

D . Ris k Assessmen t Input s Estimate s o f annua l incidenc e an dmaximu m lifetim e individua l ris k associate dwit hth e emission s o f hexavalen t chromiu m fro m th e chromiu

m platin g sourc e categor y wer e calculate dusin g EPA' s Huma nExposur e Mode l (HEM) . Input s t o th e mode l includ e plan t locations , estimate demissio n rates , an

dstac k discharg e parameter s (e.g. , ga s velocity , temperature , stac k height , etc.) . Becaus e o f th e larg e numbe r an ddiversit y

o f plant s withi nthi s sourc e category , input s t o th e HEM wer e no t obtaine dfo r th e individua l plants . Instead , mode l plant s wer e develope dusin g industr y dat a an dwer e site daccording t o th e method s describe dbelow . A detaile d descriptio no f th e methodolog y use dt o develo phealt hris k assessmen t input s fo r thi s sourc e categor y i s presente di na separat e memorandu m (B . Duletsky , MRI , t o A . Vervaert , EPA:ISB , Jul y 31 , 1985 . Ris k 1 9 assessmen t input s fo r chromiu m electroplatin g sourc e category. ) 1 . Annua l incidence . Th e ris k assessmen t input s use dfo r calculatin g nationwid e incidenc e ar e presente dinTabl e 4 . Input s wer e develope dfo r two mode l plants , on e representativ e o f har dplater s an don e representativ e o f decorativ e platers . I t wa s estimate dtha t har dplater s accoun t fo r abou t 7,30 0 o f th e estimate d9,70 0 plant s involve dinchromiu m plating , whil e decorativ e plater s accoun t fo r abou t 2,40 0 plants . Th e estimat e i s base do ninformatio nonnationwid e chromi c aci dconsumptio n tha t indicate s tha t 7 5 percen t o f th e chromi c aci dconsume db y plater s i s consume db

y har dplater s an

d2 5 percen t i s consume db y decorativ e platers . Th e emissio nrate s fo r th e mode l plant s wer e calculate dbase d
o nth e uncontrolle demissio nfactor s presente di nTabl e 2 , th e previousl y cite dinformatio no nchromi c aci dconsumption , an destimate s o f th e leve l
o f emissio ncontro l currentl y i nplac e withi nth e sourc e category . Fo r the hardplaters , i t i s assume dtha t 5 0 percen t ar e controlle dt o 9 0 percen t base do nth e us e o f mis t eliminator s an dscrubbers , an

dtha t the balanc e ar e uncontrolled . I nth e cas e o f decorativ e platers , i t i s assume dtha t 9 0 percen t ar e controlle dt o 8 0 percen t an dtha t 1 0 percen t
ar e uncontrolled . Th e 8 0 percen t contro l leve l i s a conservativ e estimat e basedo nth e us e o f fum e suppressant s tha t inhibi t emissions . Th e stac k

# r P.1 4

TABL E 4 . RIS KASSESSMEN T INPUT S FO RCALCULATINGANNUA L INCIDENC E DUE TO HEXAVALEN T CHROMIU M EMISSION S FRO

M T^ | CHROMIUM ELECTROPLATIN GSOURC E CATEGORY
Plan t name/location :

Typ e o f source : Emissio nrates , kg/yr : Tota l C r Hexavalen t C r Discharg e parameters : Stac k height , m Vertica l area, m Ven t typ e Stac k diameter , m Ga s exi t velocity , m/ s Ga s temperature , ° K Har d chromiu m platin g mode l plan t t o be applie d a t 7,30 0 locations , dis tribute d accordin g t o populatio n density . H (stack ) Decorativ e chromiu m platin g mode l plan t t o b e applie d a t 2,40 0 locations , distribute daccord in g t o populatio n density . H (stack )



### 7. 7 7. 7

1 0 5 0 0 (vertica l stack ) 

### 0. 5 1 5 300 0. 1 0. 1

1 0 5 0 0 (vertica l 

### 0. 5 1 5 30 0 stack )



### 1 0P.1 5

discharg e parameter s reflec t typica l value s obtaine dfro m informatio n gathere donnumerou s platers . Incalculatin g th e aggregat e annua l incidence , th e mode l har dplatin g plan t wa s distribute damon g 7,30 0 site s an dth e mode l decorativ e platin g plan t wa s distribute damon g 2,40 0 sites . Th e plant s wer e site daccordin g t o populatio ndensity , whic hi s a reasonabl e metho do f distributio n becaus e chromiu

m electroplatin g operation s ar e use db y man y differen t industrie s an

dar e usuall y

locate di nmor e populate dindustria l areas . Th e
annua l incidenc e o f cance r resultin g fro m hexavalen t chromiu

m emission s 2 1 fro m chromiu

m electroplatin g operation s i s 3 2 statistica l lives . 2 . Maximu

m lifetim

e risk . Th e ris k assessmen t input s use dfo r calculatin g maximu

m lifetime ris k ar e presente dinTabl e 5 . Fou r mode l plant s wer e use dt o represen t th e followin g genera l subcategorie s o f chromiu m platers : smal l har dplaters , larg e hardplaters , smal l decorativ e platers , an dlarg e decorativ e platers . Chromi c aci d consumptio nan

dstac k parameter s fo r th e fou r mode l plant s wer e base do n dat a provide db

y fou r actua l platin g plants . Th e mode l plant s wer e site d
a t th e locatio no f a fift hplatin g plan t i na commercial/residentia l are a
nea r Detroit , Michigan . Thi s locatio ni s representativ e o f th e type s o f
area s i nwhic hman

y platin g plant s ar e located . Althoug heac ho f th e fou r actua l plant s ha s ai r pollutio ncontro l device s i nplace , al l emission s from th e mode l plant s wer e assume dt o be uncontrolle dfo r the purpos e o f assessin g maximu m lifetime risk . Emissio n rate s wer e calculate dusin g th e chromi c aci dconsumptio nfo r eac hplan t
an dth e factor s fo r uncontrolle demission s liste di nTabl e 2 . Th e annua l incidenc e an dmaximum

lifetime risk s attribute dt o uncon trolle dhexavalen t chromiu m emission s fro

m thes e mode l plant s ar e liste d i nTabl e 6 . A s show

nonth e table , th e maximu m ris k o f 8. 2 xlO " i s du e t o emission s fro

m th e larg e har dplater . Th e maximu m lifetime risk s du e t o emission s fro

m th e sam

e mode l plant s locate dinmor e densel y populate d
area s (Ne

w Yor k an dLo s Angeles ) wer e als o estimate dan dar e abou t two

4 time s greate r thanth e risk s liste di nTabl e 6 an dexcee d1. 0 xl O .



### 1 1P.1 6

TABL E 5 . RIS KASSESSMEN T INPUT S FO RCALCULATINGMAXIMU

M LIFETIM E RIS K DU E T O HEXAVALEN T CHROMIU M EMISSION S FRO

M TH E CHROMIU M ELECTROPLATINGSOURC E CATEGORY

Mode l plant a : Typ e o f platin g operation :

Chromi c aci dusage , kg/yr :
Tota l tan k surfac e area , m :

Typ e o f source : Uncontrolle d emissio nrates , kg/yr : Tota l C r Hexavalen t C r Discharg e parameters : Stac k height , m Vertica l area , m Ven t typ e Stac k diameter , m Ga s exi t velocity , m/ s Ga s temperature , ° K Smal l har d


### 81 6 4. 6

H (stack )

7 ' 7 h 7.7 b



### 7. 3 50 0 (verti cal ) 0.6 1 

### 9. 7 300 Larg e

hard

9,60 7 18. 9

H (stack )

90.3 b 90.3 b



### 2 3 250 0 (verti cal ) 

### 1. 3 7. 1 29 4 Smal l decora tive 1,08 9 

### 5. 6

( H stack )

0.26 c 0.26 c



### 7. 9 5 0 0 (verti cal ) 0.6 1 10. 1 

### 29 4 Larg e decora tiv e 16,33 0
22. 3

( H stack )

3.9 C 3.9 C



### 2 5 250 0 (verti cal ) 

### 1. 6 7. 1 294

a Fo r th e purpos e o f determinin g maximu m lifetim

e risk , eac hplan t i s t o b e locate d a t th e sit e o f a nexistin g plan t inth e Detroi t are a (UT M zon e 17 ; 3 , 35 , 12 2 E ; 47 , 02 , 24 4 N) . + 6 D Base d o nanuncontrolle d emissio nfacto r o f 0.009 4 k g C r /k

g Cr0 3 . (Ref. : EPA

Sourc e Tes t a t Carolin a Plating—Rol l Division 6 plant. ) c Base d o nanuncontrolle demissio nfacto r o f 0.0002 4 k g C r /k g Cr0 3 , whic hassume s an8 0 percen t contro l efficienc y fo r th e fum

e suppressan t use d durin g th e EP

A sourc e test . (Ref : EPA Sourc e Tes t a t C . S . Oh m Manufacturin g Compan y plant. )



### 1

2P.1 7

TABL E 6 . RISK S ASSOCIATE D WIT H EXPOSUR E T O UNCONTROLLE D HEXAVALEK T CHROMIU M EMISSION S FRO

M MODE L CHROMIU

M ELECTROPLATIN GOPERATION S

Mode l plant a

Smal l hard Larg e har d Smal l decorativ e Larg e decorative 0 Annua l inc i

0.00 3
0.02 6 0.000 1
0.00 1 denc e Maximu m lifetime ris k

4. 1 xlO' 5
8. 2 xlO" 5
1. 3 xlO" 6
2. 8 xlO - 5

Mode l plant s wer e site da t th e locatio no f a nexistin g platin g plan t i n .Warren , Michigan , a representativ e commercial/residentia l area . "Risk s ar e scale d u

p b y a facto r o f 0.26/0.0 5 (estimate d uncontrolle d emissions/estimate d emission s whe nusin g a fum e suppressant) . c Risk s ar e scale du

p b y a facto r o f 3.9/0.5 1 (estimate d uncontrolle d emissions/estimate d emission s whe nusin g a fume suppressant) .



### 1 3P.1 8

E . Reference s 1 . Radia nCorporation . Addendu m t o "Estimate s o f Populatio nExposur e t o Ambien t Chromiu

m Emissions " Octobe r 198 3 Fina l Report . Prepare d fo r U . S . Environmenta l Protectio nAgency . Researc hTriangl e Park , Nort h Carolina . Jul y

1984 . p . 20 . 2 . Memorandu

m fro m Duletsky , B. , MRI , t o Vervaert , A. , EPA/ISB . Jul y 31 , 1985 . Ris k assessmen t input s fo r chromiu m electroplatin g sourc e category . Attachmen t A . 3 . Referenc e 1 , pp . 14-16 . 4 . Referenc e 1 , p . 16 . 5 . Dabpernell , G . Chromium . In : Moder nElectroplating , Lowenheim , F . A . (ed.) . Ne w

York , Joh nWile y

an dSons , Inc . pp . 100-151 . 6 . Memorandu

m from Duletsky , B. , MRI , t o Vervaert , A. , EPA/ISB . May 20 , 1985 . Tri prepor t fo r Carolin a Plating—Rol l Division , Greenville , Sout hCarolina . 7 . Memorandu

m fro m Duletsky , B. , MRI , t o Vervaert , A. , EPA/ISB . Apri l 26 , 1985 . Tri p repor t fo r C . S . Oh m Manufacturin g Company , Sterlin g Heights , Michigan . 8 . Referenc e 2 , pp . 4-5 . 9 . Telecon . Duletsky , B. , MRI , wit hDargis , R. , McGean-Rohco . Jul y 22 , 1985 . Informatio nabou t fume suppressants . 10 . Telecon . Duletsky , B. , MRI , wit hStanton , D. , Dual ! Industries . Jul y 29 , 1985 . Informatio nabou t mis t eliminators . 11 . Sourc e Emissio nTestin g o f th e Buildin g 19 5 Platin g Shop , Norfol k Nava l Shipyard , Portsmouth , Virginia , 11-1 8 Marc h1985 . Repor t No . NEES A

2-124 . Ma y

1985 . p . 25 . 12 . Telecon . Duletsky , B. , MRI , wit hWoll , R. , Ai r Plastics , Incorporated . Apri l 5 , 1985 . Informatio nabou t scrubbe r contro l systems . 13 . Entro y

Environmentalists , Inc . Emissio nTes t Repor t fo r Carolin a Plating—Rol l Division , Greenville , Sout hCarolina . Second Draft . Prepare dfo r U . S . Environmenta l Protectio nAgency . Researc h Triangl e Park , Nort hCarolina . Octobe r 1985 . 14 . Sourc e Emissio nTestin g an d Industria l Ventilatio nSurve y o f Buildin g 21 0 Platin g Sho pa t Long Beac hNava l Shipyard , Long Beach , California , 7 Ma y

- 2 Jun e 1984 . Repor t No . NEES A 2-119 . Septembe r 1984 . p . 44 . 1 4P.1 9

15 . Telecon . Duletsky , B. , MRI , wit hBumsha , M& T Chemicals , Inc . Jul y 29 , 1985 . Informatio nabou t fume suppressants . 16 . Memorandu

m fro m Duletsky , B. , MRI , t o Vervaert , A. , EPA/ISB . Apri l 26 , 1985 . Tri p repor t fo r Genera l Plating , Inc. , Detroit , Michigan . 17 . Telecon . Duletsky , B. , MRI , wit hChessin , H. , M& T Chemicals , Inc . Jul y 12 , 1985 . Informatio nabou t factor s tha t affec t emission s fro m chromiu m electroplatin g processes . 18 . Memorandu

m fro m Duletsky , B. , MRI , t o Vervaert , A. , EPA/ISB . Augus t 21 , 1985 . Cost s fo r contro l options—chromiu m electroplating . 19 . Referenc e 2 , pp . 7-8 . 20 . Repor t t o th e Scientifi c Revie w Pane l onChromium . Californi a Ai r Resource s Boar d an

d th e Californi a Departmen t o f Healt hServices . Marc h1985 . p . 1-5 . 21 . Memorandu

m an d attachment s fro

m Patrick , D. , EPA/PAB , t o Cuffe , S. , EPA/ISB . Novembe r 13 , 1985 . Fina l ris k analyse s fo r hexavalen t chromiu m fo r Phas e I studies . 22 . Referenc e 2 , p . 2 . 23 . Referenc e 2 , p . 3 .



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