### 53476 6

, ^ . ; -
U.S

. Environmenta l Protectio n Agency Regio n VII I November

, 199 8 Operabl e Uni t 9 Californi a Gulc h Superfun d Sit e Leadville

, 

# E P A Announce s It s Preferre d Alternativ e Thi s Proposed Plan** describe s th e U.S

. Environmenta l Protectio n Agency' s (EPA's ) propose d alternative fo r reducin g healt h risk s t o resident s fro m lea d i n soil s an d othe r source s withi n Operabl e Uni t 9 (OU9 ) o f th e Californi a Gulc h Superfun d Sit e i n Leadville

, Colorado

. Th e Colorad o Departmen t o f Publi c Healt h an d Environmen t (CDPHE ) ha s participate d i n th e decision-makin g process an d
concur s wit h thi s alternative

. Thi s Pla n i s consistent wit h on-goin g CERCLA activitie s a t th e site

. Th e preferre d alternativ e consist s o f a multi-medi a pla n t o reduce lea d exposur e t o childre n fro m lea d i n soil
, dust
, interio r an d exterio r paint , leade d plumbin g fixtures

, craft s and hobbie s involvin g lead
, and othe r potentia l source s beyon d a n individua l residence

. T h e preferre d alternativ e wil l als o includ e communit y protectiv e measure s suc h a s zonin g an d deed restrictions , permitting , an d othe r measure s develope d wit h loca l communit y input

. Th e propose d alternativ e i s a pilo t b y EPA

. Th e progra m wil l b e reviewe d periodicall y t o ensur e tha t huma n healt h i s bein g protected

. Thi s pilo t i s bein g propose d i n recognitio n o f th e uniqu e climatic conditions i n Leadville

, an d th e stron g communit y interes t i n managin g exposur e t o lead

. MAR K YOU R CALENDAR : OPPORTUNITIE

S FO R PUBLI C INVOLVEMEN T Publi c Meeting : Thursda y Novembe r 19,199 8 7:00p m Minin g Hal l o f Fam e Leadville

, Colorad o Publi c Commen t Period : Novembe r 12,199 8 - Decembe r 14,199 8 Sen d Comment s to : Rebecc a Thoma s EP A Projec t Manage r 99 9 18 * Street

, Suit e 50 0 Denver

, Colorad o 80202-240 5 (303)312-655 2 Toll-fre e (800 ) 227-891 7 ext

. 655 2 Informatio n

Repositories : The Proposed Plan and other documents in the Administrative Record are available at the following locations: Lak e Count y Publi c Librar y 111 5 Harriso n Avenu e Leadville

, C O 8046 1 Colorad o Mountai n Colleg e Librar y Learnin g Resourc e Cente r Leadville

, C O 8046 1 E P A Superfun d Record s Cente r 99 9 18 * Stree t 5 * Floor

, Nort h Terrac e Denver

, C O 8020 2 (303)312-647 3 Rebecc a Thoma s EP A Projec t Manage r 99 9 18 * Street

, Suit e 50 0 Denver

, Colorad o 80202-240 5 (303)312-6552 

### K e

y Contact s Rus s Alie n CDPH E Stat e Projec t Office r (303)692-338 2 

### Mario n

Galan t CDPH E Communit y Relation s Coordinato r Toll-fre e (888 ) 569-183 1

* * Word s show n i n bol d italic s ar e define d i n th e glossar y a t th e en d o f th e document

.TABL

E O F CONTENT S Preferre d Alternative...........................pag

e 1 

### Publi c Commen t Period........................pag

e 1 Publi c Involvemen t Process...................pag

e 2 

### Sit e Background.................................pag

e 2 Assessment o f Sit e Risks......................pag

e 3 Remedia l Actio n Objectives..................pag

e 4 Ris k Managemen t Approach..................pag

e 4 Summar y o f Alternatives......................page

4 Cleanu p Evaluatio n Criteria.....................pag

e 7 Compariso n o f Alternatives...................pag e

7 Summar y o f the Preferre d Alternative......

. pag e 9 Acronyms.....................................................page

9 Glossary.......................................................page

9 Th e purpos e o f thi s Propose d Pla n i s t o provid e the * publi c wit h informatio n abou t th e propose d alternatives fo r OU 9 an d t o solici t publi c input

. Thi s Propose d Pla n wa s prepare d t o fulfil l EPA' s publi c 

### participatio n responsibilitie s unde r Section s 113(k )

an d 117(a ) o f th e Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) o f 1980 , a s amende d b y th e Superfund Amendments and Reauthorization Act (SARA) of 1986.

EP A encourage s resident s an d othe r intereste d partie s t o rea d an d commen t o n thi s Propose d Pla n an d th e Remedial Investigation/Feasibility

Study (RI/FS ) fo r OU9

. Thes e document s describ e th e OU 9 contaminatio n an d th e cleanu p alternative s considered

. Th e Propose d Pla n i s base d on th e finding s o f th e RI/F S an d othe r applicabl e documents

. Thes e report s ar e include d i n th e Administrative Record fo r th e Californi a Gulc h Superfun d Site

. Th e Administrativ e Recor d contain s al l o f th e informatio n upo n whic h selectio n o f a n appropriat e remed y wil l b e based

. Th e publi c i s encourage d t o commen t on al l identifie d alternatives
, a s wel l a s provid e new informatio n fo r EP A t o consider

. Comment s o n th e Propose d Pla n ca n b e submitte d eithe r orall y o r i n writin g a t th e publi c meetin g o n Novembe r 19,1998 , o r writte n comment s ca n b e sent , t o Rebecc a Thoma s a t th e addres s provide d o n pag e I

, postmarke d no t late r tha n Decembe r 14 , 1998

. Upo n timel y request , th e commen t perio d ma y b e extended

. Such request s shoul d b e submitte d i n writin g t o Rebecc a Thoma s an d postmarke d n o late r than Decembe r 14 , 1998

. Afte r considerin g al l comments, EP A wil l mak e it s fina l cleanu p decision

. EP A ma y modif y th e preferre d alternative
, selec t another alternativ e presente d i n thi s Propose d Plan

, o r selec t anothe r alternativ e base d o n ne w informatio n o r public comments

. Th e fina l cleanu p decisio n wil l b e publishe d i n a Record o f Decision (ROD ) tha t respond s t o al l comment s an d document s EPA' s rational e fo r th e selecte d remed y a t OU9

. , Sit

e History

. Th e Californi a Gulc h Sit e i s locate d i n an d aroun d Leadville

, Colorado

, abou t 10 0 mile s southwes t o f Denver

. Figur e 1 i s a genera l ma p o f th e Californi a Gulc h Site

. A s see n i n Figur e 2 , OU 9 encompasses bot h residentia l an d ope n spac e area s withi n th e Site

. Th e Leadvill e area , includin g portion s o f OU9

, wa s th e sit e o f extensiv e mining , milling
, an d smeltin g operation s tha t bega n abou t 1860

. Mos t minin g operation s cease d aroun d 1900 , although som e facilitie s continue d intermitten t operation s a s lat e a s th e 1960s

. Mos t o f th e mine s withi n th e Sit e boundar y are presentl y inactive , an d al l o f th e mill s an d smelter s hav e bee n demolished

. Regulator y History

. EP A place d th e Sit e o n th e National Priorities List (NPL ) i n 198 3 mainl y du e t o concer n ove r th e impac t o f min e drainag e o n surfac e water s i n th e Californi a Gulc h an d th e Arkansa s River

. Subsequen t sit e investigation s reveale d th e presence o f heav y metal s i n soil s an d i n wast e pile s i n an d
aroun d th e curren t residentia l are a o f Leadville

. Base d o n a baselin e human health risk assessment fo r resident s a t th e Sit e (EP A 1996a , 1996b)

, EP A an d the Stat e identifie d lea d a s the contaminan t o f potentia l concer n t o huma n healt h (EP A 1996c)

. Othe r metal s i n th e surfac e soil s d o no t pos e a significan t healt h ris k t o the resident s (EP A 1996b)

. Thi s respons e actio n i s onl y on e o f severa l action s tha t
ar e planne d o r ar e currentl y underwa y t o minimiz e 

### exposures an d risk s fro m lea d contaminatio n i n residentia l area s o f Leadville

. Fo r example
, certai n wast e roc k pile s locate d i n residentia l area s ar e bein g remove d t o contro l exposure s fro m direc t contac t an d t o reduce ambien t dust sources

. I n addition
, a community-base d progra m ("Kid s First" ) wa s implemente d i n 199 5 t o respon d t o request s fro m concerne d citizen s t o investigat e and addres s exposur e t o lea d fro m a variet y o f potentia l sources ,includin g soil
, dust
, drinkin g wate r and paint

. Othe r activitie s includ e remediatio n o f tailings an d slag pile s alon g wit h measure s t o improv e surfac e wate r quality

.
Durin g th e Remedia l Investigation/Feasibilit

y Stud y (RI/FS)

, a baselin e huma n healt h ris k assessmen t wa s conducted

. Par t A o f thi s ris k assessmen t (EP A 1996a ) examined risk s t o resident s fro m lead
, focusin g specificall y o n risk s t o youn g childre n (age 0 t o 6 years)

. Childre n wer e selecte d a s th e focu s o f thi s ris k assessmen t becaus e childre n typicall y hav e highe r intake rate s pe r uni t bod y weigh t o f environmenta l medi a tha n adults
, childre n ten d t o absor b a highe r fractio n o f ingeste d lea d fro m th e gastrointestina l trac t tha n d o adults
, an d childre n ten d t o b e mor e susceptibl e t o som e o f th e advers e effect s o f lea d tha n adult s (especiall y impairmen t o f th e nervou s system)

. Ris k Assessmen t Approac h fo r Lead

. Th e ris k assessmen t fo r lea d wa s supporte d b y a larg e bod y o f site-specifi c dat a tha t include d no t onl y extensiv e measurement s o f lea d i n soi l an d dus t i n residentia l locations
, bu t als o a n extensiv e demographic s survey , dat a o n lea d level s i n wate r an d pain t (bot h interio r an d exterior)

, dat a o n th e physica l an d chemica l form s o f lea d a t variou s location s aroun d th e community , an d a n informativ e community-wid e bloo d lea d stud y involvin g 31 4 childre n (abou t 65 % o f th e tota l populatio n o f childre n a t the site)

. Thes e dat a wer e use d t o suppor t tw o paralle l line s o f investigatio n and
assessmen t Th e firs t o f thes e employe d EPA' s Integrate d Exposur e Uptak e an d Biokinetic (IEUBK ) mode l t o calculat e th e expecte d impac t o f lea d level s i n soi l an d dus t o n bloo d lead level s i n are a children

. The secon d approac h compare d th e measure d bloo d lea d value s i n are a childre n wit h relevan t nationa l bloo d lead statistic s i n orde r t o hel p evaluat e the curren t impact s o f actua l sit e exposure s t o lead

. Finding s an d Conclusions

. Th e mai n finding s o f th e ris k assessmen t fo r lead ar e summarize d below : 1

. I n 1991, geometri c mea n bloo d lea d level s i n childre n livin g withi n the sit e boundarie s wer e typicall y aroun d 5- 6 ug/dL

, whic h wa s abou t 1

- 1. 5 ug/d L highe r tha n reporte d geometri c mea n value s fo r childre n o f simila r ag e an d se x livin g i n othe r area s acros s th e nation

. 2

.

I n 1991 , th e site-wid e frequenc y o f childre n exceedin g EPA' s health-base d bloo d lea d targe t o f 1 0 ug/d L wa s abou t 8%
, whic h i s somewha t highe r tha n th e targe t o f n o mor e tha n 5 % abov e 1 0 ug/dL

. Thi s wa s indicativ e o f a situatio n whic h exceede d EPA' s goa l o f n o individua l chil d
or grou p o f similarl y expose d childre n havin g a greate r tha n 5 % chanc e o f exceedin g a bloo d lea d leve l o f 1 0 ug/dL

. I n som e sub-area s o f th e site , th e ris k o f exceedin g 1 0 ug/d L appeare d t o b e substantiall y highe r (10%-25% ) tha n th e site

wid e average
. Additiona l bloo d lead dat a collecte d b y count y healt h agenc y fro m mor e tha n 10 0 childre n pe r yea r fo r eac h yea r betwee n 199 1 an d th e presen t suggest s tha t th e incidenc e o f childre n i n the communit y wit h bloo d lead level s abov e 1 0 ug/d L i s continuin g t o fluctuat e betwee n 6%and9%

. 3

. Ther e i s a statisticall y significan t correlatio n between lea d level s i n soi l an d dust an d bloo d lea d level s i n children

. 4

. Bot h interio r an d exterio r lead-base d pain t contribut e t o ris k o f elevate d bloo d lead level s i n som e children
, mainl y b y addin g t o the concentratio n o f lead i n soi l and/o r dust i n thos e home s wher e lead-base d pain t i s a potentia l sourc e o f lea d exposure

. 5

. Th e result s o f th e IEUB K mode l ru n usin g defaul t soi l an d dus t ingestio n rate s predicte d bloo d lead level s tha t wer e highe r tha n observed

. I t wa s conclude d tha t soi l an d dust ingestio n rate s i n thi s communit y wer e probabl y somewha t lowe r tha n the nationa l averag e values
, possibl y becaus e the groun d i s froze n o r snow-covere d approximatel y eigh t month s ou t o f th e year
. Loca l effort s t o minimiz e lea d exposur e throug h a n extensiv e educatio n and interventio n progra m migh t als o explai n som e o f th e variatio n i n predicte d versu s currentl y observe d bloo d lea d levels

. 6

. Base d o n th e analyses conducted
, th e ris k assessmen t reache d th e conclusion tha t soi l lea d i s a relativel y mino r sourc e o f exposur e a t location s wher e lead level s wer e les s ma n abou t 

### l,000ppm

. Exposur e vi a soi l probabl y di d no t becom e a dominant sourc e o f exposur e unti l lea d level s wer e abov e 3,50 0 ppm

. Othe r source s o f lea d contributin g t o curren t exposur e include d interior an d exterior pain t an d indoo r dust

. Lea d level s i n th e wate r supplie d b y th e municipa l wate r syste m ar e no t o f concern , bu t lea d level s i nsom e shallo w well s ar e hig h enoug h tha t i t woul d
no t b e saf e t o us e thos e well s a s a routin e sourc e o f drinkin g water

. EP A guidanc e (EPA1994 ) state s tha t EP A should : ...limi t exposur e t o soi l lea d level s suc h tha t a typica l (o r hypothetical[potentiall

y exposed] ) chil d o r grou p o f similarl y expose d childre n woul d hav e a n estimate d ris k
o f n o mor e tha n 5 % o f exceedin g th e 1 0 ng/d L bloo d lea d level

. I n accordanc e wit h thi s polic y recommendation
, th e Remedial Action Objectives (RAOs ) a t thi s Sit e agree d t o i n th e 199 4 Wor k Are a Managemen t Pla n (U.S

. Distric t Court

, 1994 ) ar e a s follows : • RAO-1 : "N o mor e than fiv e percen t o f al l childre n (ag e 0 t o 7 2 months ) wh o liv e a t thi s site , eithe r no w o r i n th e future

, wil l hav e bloo d lead value s highe r thanlOug/dL "
• RAO-2 : "Healt h wil l b e adequatel y protecte d i f th e highes t ris k leve l a t an y sub-locatio n i s a probabilit y n o highe r tha n on e percent tha t a populatio n o f childre n (ag e 0 t o 7 2 months ) residin g a t tha t sub

locatio n wil l excee d a bloo d lea d valu e o f I S ug/dL. " Thi s secon d RA O i s intende d mainl y t o hel p guar d agains t potentia l exposure s a t sub-area s o f th e sit e wher e lea d exposure s ten d t o b e highe r tha n average
. A s note d above
, th e traditiona l approac h use d b y EP A t o addres s th e potentia l fo r elevate d bloo d lea d level s i n a communit y i s t o emplo y th e IEUB K mode l t o predic t th e ris k tha t childre n wil l hav e elevate d bloo d lea d value s fro m exposur e t o lead i n soil
, dust
, food

, wate r an d air

. I f th e ris k i s abov e EPA' s health-base d goal
, soil s ar e remediate d suc h tha t remedia l actio n objective s ar e me t I f th e defaul t IEUB K model input s ar e used
, thi s correspond s t o a soi l lead-actio n leve l o f abou t 40 0 ppm

. I f site-specifi c dat a an d inference s fro m Leadvill e ar e incorporate d int o th e model
, th e soi l actio n level s rang e fro m 1,10 0 -1,400

. 

### ppm

. A t thi s site , a non-traditiona l ris k managemen t ~ approac h i s bein g proposed

. The objectiv e i s t o reduc e childhoo d lea d exposur e b y al l identifiabl e routes, includin g no t onl y soi l bu t also dust
, water , an d paint , a s wel l a s othe r potentia l source s o f exposur e bot h withi n an d beyon d a n individua l residence

. 

### Cleanin g u p residentia l location s wher e soi l level s excee d 3,50 0 pp m o f lead
, couple d wit h reduction s i n exposur e fro m othe r sources , wil l reduc e the probabilit y o f harmfu l exposur e o f childre n livin g i n Leadvill e an d surroundin g residentia l area s an d i s expecte d t o hel p reduc e th e incidenc e o f childre n wit h bloo d lead level s highe r tha n 1 0 ug/d L t o a level tha t meet s o r exceed s th e RAOs

. Actua l o r threatene d release s o f hazardou s substance s fro m thi s site , i f not addresse d b y the preferre d alternativ e o r on e o f th e other activ e measure s considered
, ma y presen t a n imminen t an d substantia l endangermen t t o publi c health
, welfare

, or th e environmen t Seve n differen t remedia l alternative s wer e analyzed fo r OU 9 (ASARCO

, 1996)

. A descriptio n o f eac h o f thes e alternative s i s provide d below

. I n eac h case , 1 2 year s o f implementatio n wa s identifie d t o simplif y cos t compariso n between alternatives

. ALTERNATIV E 1 : NOACTION

. Cost : $ 0 Year s o f Implementation : Non e Th e Superfun d progra m require s tha t th e "n o action " alternativ e b e evaluate d a t ever y sit e t o establis h a baselin e fo r comparison

. Unde r thi s alternative
, EP A woul d tak e n o furthe r actio n a t th e sit e t o preven t exposur e t o th e soi l contamination

. ALTERNATIV

E 2 : INSTITUTIONA

L CONTROL S O R COMMUNIT Y PROTECTIV E MEASURE S (CPMs) Cost : $128,94 0 Year s o f Implementation : 1 2 Institutiona l Controls

, or Communit y Protectiv e Measure s (CPMs)

, ma y includ e zoning/dee d restrictions , permittin g requirements , temporar y 

### acces s restrictions , an d communit y awarenes s education

. Deed restriction s coul d legall y limi t o r prohibi t futur e land us e i n th e sourc e area
. CPM s alon e ma y b e appropriat e an d acceptabl e remedia lactio n alternatives fo r som e residentia l are a soil s sourc e sites

. This alternativ e ma y als o b e a n elemen t o f other alternatives ; i f so , temporar y acces s restrictio n suc h a s fencin g an d poste d warning s woul d onl y b e use d t o physicall y contro l acces s t o th e residentia l are a soil s durin g constructio n activities

. combine

d wit h containmen t o f bot h surfac e wate r an d sourc e surfaces

. Surfac e wate r contro l ma y b e implemente d throug h diversio n ditche s an d culvert s a s discusse d i n Alternativ e 3

. Th e sourc e surfac e contro l elemen t o f containmen t involve s i n situ mixing , revegetation , o r a soi l cove r a s discusse d i n Alternativ e 4

. ALTERNATIV E 3 : CONTAINMEN

T (SURFAC E WATE R CONTROLXCPM s Cost : $619,20 0 Year s o f Implementation : 1 2 Alternativ e 3 fo r th e residentia l are a soil s include s th e CPM s describe d i n Alternativ e 2 combined wit h surfac e wate r containment

. Th e containment componen t o f thi s alternativ e include s surfac e wate r contro l method s suc h a s diversio n ditche s an d culverts

. Th e diversio n ditche s woul d b e constructe d t o diver t surfac e wate r flo w an d run-of f awa y fro m an d aroun d th e sourc e areas

. Covere d culvert s woul d b e constructe d t o conduc t surfac e wate r flo w throug h

mor e populate d areas

. Thes e control s woul d reduc e th e potentia l fo r transpor t o f metal s awa y fro m th e sourc e are a and
, therefore

, reduc e metal s impact s t o surfac e wate r o r other areas

. ALTERNATIV E 4 : CONTAINMEN

T (SOURC E SURFAC E CONTROL)/CPM S Cost : $1,176,86 0 Year s o f Implementation : 1 2 Thi s alternativ e include s th e CPM s describe d i n Alternativ e 2 combined wit h method s fo r sourc e surfac e containment

. Th e containment componen t o f thi s alternativ e woul d b e base d o n sourc e surfac e contro l option s includin g soi l covers , i n situ mixing , an d revegetation

. Soi l cove r involve s addin g additiona l fil l t o isolat e th e impacte d surfac e soil

. I n situ mixin g involve s tilling surfac e soi l wit h deepe r soil

. Revegetatio n involve s plantin g appropriat e cove r vegetatio n t o lesse n infiltration

, leaching
, an d erosion

. ALTERNATIV E 5 : CONTAINMEN

T (SURFAC E WATER CONTROL

, SOURC E SURFAC E CONTROLVCPM S Cost: $1,599,67 0 Year s o f Implementation : 1 2 Alternativ e 5 fo r th e residentia l are a soil s source s include s the CPM s describe d i n Alternativ e 2 ALTERNATIV

E 6 : REMOVAL/TRANSPORTATION

/ DISPOSAL / CPM S Cost : $6,311,65 0 Year s o f Implementation : 1 2 Thi s alternativ e include s th e CPM s describe d i n Alternativ e 2 combine d wit h removal
, transport , an d disposa l o f residentia l are a soil s wher e mea n lea d level s ar e greate r tha n 3,50 0 ppm

. Th e residentia l
are a soil s woul d b e excavate d b y han d wit h th e ai d o f smal l conventional earth-movin g equipment an d replace d wit h clea n fill

. Excavate d material s woul d b e haule d b y truc k t o a n on-sit e repository , consolidate d i n a n existin g on-sit e tailing s pile
, o r remove d t o som e othe r designate d area
. ALTERNATIV E 7 : LAK E COUNT Y COMMUNIT Y HEALT H PROGRA M (EPA' s preferre d alternative' ) Cost: $4,758,00 0 Years o f Implementation : 12 , or unti l Remedia l Actio n Objective s (RAOs ) ar e achieved Alternativ e 7 consist s o f th e implementatio n o f th e Lake Count y Communit y Healt h Progra m (LCCHP)

. The progra m i s a multi-media pla n t o reduc e lea d exposur e t o childre n i n Leadvill e and surroundin g areas

. Potentia l source s tha t woul d b e considere d includ e no t onl y soi l an d dust
, bu t als o interio r an d exterior paint , leade d plumbin g fixtures

, craft s an d hobbie s involvin g lead
, an d othe r potentia l source s beyon d a n individua l residence

. Alternativ e 7 ma y als o includ e communit y protectiv e measure s suc h a s zonin g an d dee d restrictions , permitting , an d othe r measure s develope d wit h local communit y input

. Th e ke y component s o f th e LCCH P ar e a s follows : • Residentia l propert y owner s withi n OU 9 ma y reques t a n investigatio n o f lead level s i n soil
, dust
, pain t an d wate r o n th e propert y (i f such a n investigatio n ha s no t alread y bee n performed)

. • Continue d voluntar y blood lea d monitorin g (wit h financia l incentives ) fo r al l childre n ag e 6

-7 2 month s an d voluntar y bloo d lea d monitorin g fo r pregnan t an d nursin g women
. • I f th e concentratio n o f lead i n bloo d o f a n 

### individua l o r i n on e o r mor e o f th e environmenta l medi a a t a residenc e exceed s a specifie d set o f "trigge r criteria" , the n appropriat e action s wil l b e take n t o addres s th e exceedance

. Thes e trigge r criteri a ar e summarize d below : Blood Lea d >10ug/dL Soi l Lea d concentratio n abov e 3,50 0 pp m Dus t Indoo r dust lea d concentratio n greate r tha n 2,00 0 ppm Pain t Interio r o r exterio r pain t wit h lea d level s abov e 1 mg/cm 1 an d i n poo r conditio n Wate r Lea d i n drinkin g wate r abov e 15ug/ L

• Whe n on e o r mor e o f th e trigge r criteri a ar e exceeded
, a rang e o f differen t respons e action s ma y b e considered

. Th e mos t appropriat e respons e action s wil l b e determine d b y th e natur e an d exten t o f th e exceedance
, th e effectivenes s i n ris k reduction
, implementability
,

impac t o n cultura l resources , propert y owne r acceptance , cost-effectiveness

, an d communit y impacts

. An y respons e actio n wil l b e conducte d t o mee t th e need s o f th e propert y owner
. A n extensiv e educatio n an d interventio n progra m t o manag e lea d exposur e a t th e sit e wil l b e a n integra l componen t o f eac h actio n considered

. Soi l remediatio n wil l b e offere d a t al l residence s wher e soi l lea d level s excee d 3,50 0 ppm

. Soi l remediatio n ma y occu r i f soil s ar e between 1,10 0 an d 3,50 0 pp m i n respons e t o a n elevate d blood lead

. An y excavate d soil s wil l b e managed an d dispose d o f properly

. Th e option s fo r eac h mediu m ar e liste d below

. Bloo d Lead

- Investigatio n and remediatio n o f potentia l exposur e sources , includin g thos e abov e an d other s (a s needed )

- Continue d bloo d lea d monitorin g

- Educatio n

- Medica l follow-up

, a s appropriat e Soi l

- Containmen t (so d placement
, cappin g wit h soil
, clay
, asphal t or cement )

- Remova l t o a n on-sit e repositor y an d replacemen t wit h clea n soi l -

Institutiona l control s

.'' Dus t

- Physica l measur e (sealin g of f dust sourc e areas )

- Remova l (vacuum

, mopping , duc t cleaning
, mats ) Pain t

- Containmen t an d coverin g (enclosure

, encapsulation
, stabilizatio n i n place )

- Remova l (scraping

, stripping , disposa l off

site )

- Institutiona l control s (disclosure

, control s durin g renovatio n activities ) Drinkin g Wate r

- Point-of-us e treatmen t syste m

- Alternativ e wate r suppl y

- Replacemen t o f lea d containin g pipes , joint s o f fixture s

- Institutiona l control s (restriction s o n groundwate r use ) Sinc e th e LCCH P i s a "pilo t project " tha t involve s a numbe r o f innovativ e approaches
, i t include s ongoin g revie w (rather tha n waitin g fo r the typica l five-yea r review ) t o ensur e tha t th e progra m i s operatin g a s intende d an d tha t huma n healt h i s bein g adequatel y protected

. An y problem s wit h th e progra m wil l b e identifie d an d adjuste d a s necessary

. Ke y component s o f th e revie w proces s ar e a s follows :

- Periodic checkin g t o ensur e adequat e participatio n o f are a resident s i n th e bloo d lea d monitorin g an d environmenta l medi a 

### samplin g programs

.

- Specia l effor t t o ensur e collectio n o f paire d bloo d lea d an d environmenta l lea d dat a wheneve r possibl e Creatio n and applicatio n o f a well

documente d qualit y assuranc e pla n t o ensur e tha t bloo d lea d an d environmenta l lea d dat a ar e collecte d an d analyze d i n th e prope r manner , an d tha t th e dat a ar e accuratel y entere d int o a n ongoin g databas e suitabl e fo r scientifi c evaluation

.

- Periodi c evaluatio n o f th e progra m b y a grou p o f outsid e scientists

.-

Annua l reportin g o f summar y statistic s an d compariso n t o Remedia l Actio n Objectives

. A s describe d i n th e nex t sections , thes e alternative s 

### wer e compare d an d evaluate d usin g EPA' s nin e evaluatio n criteri a establishe d i n th e National Contingency Plan (NCP)

. Thes e seve n alternative s wer e evaluate d i n detai l usin g th e criteri a summarize d below

. Th e firs t two evaluatio n cleanu p criteria , overal l protectio n o f huma n healt h an d th e environment , an d complianc e wit h Applicable o r Relevant an d Appropriate Requirements (ARARs)

, are threshol d criteri a tha t mus t b e me t b y th e selecte d remedia l action

. Th e nex t fiv e criteri a are considere d primar y balancin g criteria

. Th e fina l tw o criteria , Stat e an d communit y acceptance , ar e modifyin g criteri a whic h th e EP A evaluate s and incorporate s befor e makin g th e fina l clean-u p decision

. Base d o n a carefu l revie w o f eac h o f th e alternatives
, EP A an d th e Stat e hav e identifie d Alternativ e 7 , Lake Count y Communit y Healt h Progra m a s th e propose d alternativ e fo r remediatio n o f th e residentia l soil s (OU9 ) a t th e Californi a Gulc h Site

. Base d o n curren t information

, thi s alternativ e bes t achieve s a balanc e amon g th e nin e criteri a tha t EP A use s t o evaluat e alternative s wit h th e understandin g tha t thi s i s a pilo t approac h tha t wil l b e evaluate d o n a continuin g basis

. Th e followin g section o f th e Propose d Pla n compare s th e propose d alternativ e an d th e othe r alternative s t o th e nin e evaluatio n criteria

. Overal l Protectio n o f Huma n Healt h an d th e Environmen t Alternativ e 7 wil l provid e th e mos t comprehensiv e protectio n o f huma n healt h and th e environmen t fro m lead
, sinc e i t addresse s no t onl y lea d i n soi l bu t als o lea d i n othe r source s suc h a s dust
, pain t an d drinkin g water

. Alternative s 5 an d 6 provid e les s protectio n sinc e the y d o no t addres s al l lea d sources

. N C P Evaluatio n Criteri a •Overal l protectio n o f huma n healt h an d th e environmen t addresse s whethe r o r no t a remed y provide s adequat e protectio n an d describe s ho w risk s pose d throug h eac h pathwa y ar e eli m inated
, reduced
, o r controlled

. •Complianc e wit h ARAR s addresse s whethe r o r no t a remed y wil l mee t al l Federa l an d Stat e environmenta l law s and/o r provid e ground s fo r a waiver

. •Long-term-effectivenes s

an d permanenc e refer s t o th e abilit y o f a remed y t o provid e reliabl e protectio n o f huma n healt h an d th e environmen t overtime

. •Reductio n o f toxicity

. mobility
, o r volum e throug h treatmen t refer s t o th e preferenc e fo r a remed y tha t reduce s healt h hazards
, the movemen t o f conta m inants , o r the quantit y o f contaminant s a t the sit e throug h treatment

. •Short-ter m effectivenes s addresse s th e perio d o f tim e neede d t o complet e th e remed y an d an y advers e effect s t o huma n healt h an d th e environmen t tha t ma y b e cause d durin g th e constructio n an d implementatio n o f th e remedy

. •Implementabilit y refer s t o th e technica l an d administrativ e feasibilit y o f th e remedy
, includin g th e availabilit y o f material s and service s neede d t o carr y ou t the remed y and coordinatio n o f Federal

, State

, and loca l government s t o wor k togethe r t o clea n u p the site

. •Cos t evaluate s th e estimate d capital an d operation an d maintenance costs o f eac h alternativ e i n compariso n t o othe r equall y protectiv e measures

. •Stat e acceptanc e indicate s whethe r the Stat e agree s with
, opposes , o r ha s no commen t o n the preferre d alternative

. •Communit y acceptanc e include s determinin g whic h component s o f th e alternative s intereste d person s i n th e communit y support , hav e reservation s about
, o r oppose

.Alternative s

3 and 4 provid e fai r protection , whil e Alternative s 1 an d 2 provid e poo r t o n o protection

. Complianc e wit h ARAR s Applicabl e requirement s ar e define d b y the NC P a s thos e cleanu p standards
, standard s o f control
, and 

### othe r substantiv e environmenta l protectio n requirements , criteria , o r limitation s promulgate d unde r federa l or stat e la w tha t specificall y addres s a hazardou s substance
, pollutant
, contaminant , remedia l action , location
, o r othe r circumstance s a t a site

. I t shoul d b e note d tha t whil e a requiremen t ma y no t b e applicabl e a s a matte r o f law
, a requiremen t ma y stil l b e "relevan t an d appropriate " i f i t regulate s o r addresse s problem s o r situations sufficientl y simila r t o thos e encountere d a t th e subjec t sit e tha t it s us e i s well-suite d t o th e particula r site

. ARARs ar e groupe d int o thre e categories : chemical-specific

, action-specifi c an d location-specific

. Alternative s 1
an d 2 d o no t compl y wit h ARARs ; Alternative s 3 an d 4 woul d onl y compl y wit h som e ARARs

, whil e Alternative s 5 , 6 , an d 7 woul d compl y wit h al l ARARs

. Long-Ter m Effectivenes s an d Permanenc e Alternativ e 1 does no t reduc e residentia l risk
, whil e Alternativ e 2 coul d b e somewha t effectiv e b y controlling/limitin g futur e use

. Alternative s 3,4 , an d 5 provid e a moderat e degre e o f long-ter m effectiveness

, bu t recontaminatio n i s likel y an d these alternative s d o rio t addres s al l lea d sources

. Alternativ e 6 woul d provid e th e highes t degre e o f long-ter m effectivenes s an d permanenc e fo r soils ; however
, i t doe s no t addres s othe r potentia l lea d
source s an d might requir e long-ter m operatio n an d maintenanc e o f a n on-sit e repository

. Alternativ e 7 woul d provid e long-ter m effectivenes s fo r man y lea d sources , bu t coul d i n som e case s us e remedie s whos e efficac y coul d decreas e wit h tim e (e.g.

, sodding
, hous e cleaning
, painting)

. Reductio n o f Toxicitv

. Mobility

, o r Volum e Throug h Treatmen t Non e o f th e alternative s reduc e Toxicity

, Mobility

, o r 

### Volum e throug h treatment

. Shor t Ter m Effectivenes s Alternativ e 1 ha s n o short-ter m effectiveness

. Alternativ e 2 coul d hav e som e short-ter m effectivenes s b y controllin g us e o f som e sourc e areas

. Alternativ e 3 coul d hav e goo d short-ter m effectivenes s i n reducin g th e potentia l fo r surfac e T f wate r impacts

. Alternative s 4,5 , an d 6 woul d no t b e effectiv e i n th e short-ter m due t o th e fac t tha t excavatio n woul d distur b soil s an d vegetatio n whic h
ma y tak e severa l year s t o re-establish

. Alternativ e 7 

### woul d hav e th e greates t short-ter m overal l effectivenes s b y prioritizin g interventio n and remediatio n i n case s o f childre n wit h elevate d bloo d lea d levels
, couple d wit h proactiv e identificatio n an d abatemen t o f di e mos t significan t source s o f lea d exposur e i n residentia l areas

. Implementabilit v Alternativ e 1 doe s no t requir e implementation

. CPM s (Alternativ e 2 ) woul d b e eas y t o implement ; however
, th e administrativ e aspect s suc h a s deed restriction s coul d pos e difficultie s i n enforcemen t Alternativ e 3 woul d b e relativel y simpl e t o implemen t sinc e mos t o f th e surfac e wate r control s coul d b e implemente d o n publi c lan d o r easements

. Alternative s 4 an d 5 woul d b e relativel y eas y t o implemen t excep t fo r acces s an d spac e limitations

. Alternativ e 6 woul d b e difficul t t o implemen t due t o spac e constriction s i n mos t residentia l yard s an d du e t o the nee d fo r locatin g a repositor y prio r t o implementatio n o f th e alternative

. Alternativ e 7 coul d b e mor e easil y implemente d becaus e th e framewor k fo r th e Lak e Count y Communit y Healt h Progra m (LCCHP ) i s currentl y i n plac e an d th e implementatio n woul d b e a n extensio n o f th e curren t Kid s Firs t Program

. Cost Alternativ e 1 ha s n o associate d cost

. Alternative s 2 an d 3 hav e a relativel y lo w cost , bu t d o no t satisf y th e remedia l objectives

. Alternative s 4 an d 5 ar e moderatel y priced
, but d o not satisf y the remedia l objectives

. Alternativ e 6 i s th e highes t cos t alternative
, bu t doe s no t address al l th e source s o f lead

. Alternativ e 7 woul d satisf y th e remedial objective s a t a moderat e cos t a s compared t o othe r alternatives

. Suppor t Agenc y Acceptanc e Th e Colorad o Departmen t o f Public Healt h an d th e Environmen t (CDPHE ) woul d b e unlikel y t o accep t Alternative s 1 throug h 4 , sinc e the y d o no t provid e adequat e protectio n o f huma n healt h an d th e environment

. Alternative s 5 an d 6 ma y b e acceptabl e becaus e lead fro m residentia l soil s woul d b e 

### effectivel y controlled

. Th e CDPH E ha s participate d i n th e decision-makin g proces s an d concur s wit h th e implementatio n o f Alternativ e 7 sinc e residentia lsoil s &n d additiona l source s o f lea d woul d b e controlled

. Communit y Acceptanc e Communit y acceptanc e o f th e preferre d alternativ e wil l b e evaluate d afte r the publi c commen t perio d 

### end s an d wil l b e describe d i n th e Recor d o f Decisio n (ROD ) fo r the site

. However

, Alternativ e 7 (LCCHP ) ha s th e suppor t o f Lak e Count y publi c healt h official s an d th e CDPHE

, a s wel l a s electe d representative s fro m bot h th e Cit y o f Leadvill e an d Lake County

. Communit y participatio n in , an d stron g suppor t for

, th e Kid s Firs t Progra m (whic h i s simila r t o th e propose d alternative ) als o indicate s communit y acceptance

. rag/cm * milligram s

pe r cubi c centimete r
. fig/d L microgram

s pe r decilite r mg/cm 1 milligram s

pe r squar e centimete r

I n summary , Alternativ e 7 woul d achieve substantia l ris k reductio n fro m lea d exposur e throug h remediatio n o f residentia l soil s and othe r source s o f lead

. Alternativ e 7 can quickl y achieve thi s ris k reductio n at a relativ e moderat e cost

. The preferre d alternativ e woul d b e protectiv e o f huma n healt h an d th e environmen t an d bes t meet s th e othe r evaluatio n criteria

. Becaus e i t i s a pilo t program , th e effectivenes s o f th e alternativ e woul d b e carefull y monitore d ove r time

.

ARAR s Applicabl e o r Relevan t an d Appropriat e Requirement s CDPH E Colorad o Departmen t o f Publi c Healt h
an d Environmen t CERCL A Comprehensive

,

Environmenta l Response

, Compensation

, an d Liabilit y Ac t o f 198 0 CPM s Communit

y Protectiv e Measures E P A U.S

. Environmenta l Protectio n Agenc y F S Feasibilit

y Stud y IEUB K Integrate d Exposur e Uptak e an d Biokineti c mode l LCCH P Lak e Count y Communit y Healt h Progra m N C P Nationa l

Contingency Pla n N P L Nationa l

Prioritie s Lis t OU 9 Operabl

e Unit 9 R A O Remedia l

Actio n Objectiv e RI Remedia l

Investigatio n RO D Recor d o f Decisio n SAR A Superfun d Amendment s an d Reauthorizatio n Act o f 198 6 p p m part s pe r millio n Administrativ e Record : Th e bod y o f document s EP A
use s t o for m th e basi s o f selectio n o f a response

. Alternative : A n optio n fo r reducin g sit e ris k b y cleanin g u p o r otherwis e limitin g exposur e t o contamination

. Applicabl e o r Relevan t an d Appropriat e Requirements : Federa l an d stat e requirement s fo r cleanup
, control
, an d environmenta l protectio n that a selecte d remed y fo r a sit e wil l meet

. Capita l Costs : Expense s relate d t o th e labor
, equipmen t an d materia l cost s o f construction

. Comprehensiv e Environmenta l Response

, Compensation

, an d Liabilit y Act : A federa l la w passe d i n 198 0 an d modifie d i n 198 6 b y th e Superfun d Amendment s an d Reauthorizatio n Act

. I t set s u p a progra m t o identif y site s wher e hazardous substanc e hav e been
, o r migh t be
, release d int o th e environment
an d t o ensur e the y are cleane d up

. Mos t o f thes e site s ar e abandone d o r ar e n o longe r active

. Feasibilit y Study : Th e F S identifie s an d evaluate s th e mos t appropriat e technica l approache s t o addres s contaminatio n problem s at a Superfun d site

. Huma n Healt h Ris k Assessment : A stud y use d b y EP A t o evaluat e risk s pose d b y a Superfun d sit e i f
n o action s ar e take n t o protec t huma n health

. Nationa l Contingenc y Plan : Th e EPA' s regulation s governin g al l cleanup s unde r th e Superfun d program

. Nationa l Prioritie s List : EPA' s lis t o f th e mos t seriou s uncontrolle d o r abandone d hazardou s wast e site s identifie d fo r possibl e long-ter m remedial response

. Operatio n and Maintenance : The cos t and timefram e o f operatin g labor
, maintenance , materials
, energy , disposal
, an d administrativ e activitie s o f the remedy

. Propose d Plan : A documen t requestin g publi c inpu t o n a propose d remedia l alternative

.Recor d o f Decision : A documen t whic h i s a consolidate d sourc e o f informatio n abou t th e site, th e remed y selectio n process , and th e selecte d remed y fo r a cleanu p unde r CERCLA

. 

### Remedia l Actio n Objectives : Medium-specifi c (e.g

. groundwater
, tailings ) goal s fo r protectin g huma n healt h an d th e environmen t Remedia l Investigation : A stud y conducte d t o identif y th e types , amounts , an d location s o f contaminatio n at a facility

. I t als o evaluate s possibl e ris k t o publi c healt h an d th e environmen t fro m exposur e t o contamination

. \ Slag : Th e soli d non-metalli c glass-lik e byproduc t forme d i n a blast furnac e o r smelte r whe n meltin g metal s o r reducin g ores

. Superfun d Amendment s an d Reauthorizatio n Act : Modification s t o CERCL A enacted o n Octobe r 17,1986

. Tailings : Th e portio n o f minera l ore s tha t i s separate d ou t durin g th e millin g o f or e an d disposed

.

ASARCO

, 1996

. Draf t Residentia l Soil s Feasibilit y Study

, Californi a Gulch Superfun d Site

, Leadville

, Colorado

. Prepare d b y Colde r Associates

. Environmenta l Protectio n Agency (EPA)

. 1995

. U.S

. Environmental Protectio n Agency

, Nationa l Cente r fo r Environmenta l Assessment

. Urban Soi l Lea d Abatemen t Demonstratio n Projec t Revie w Draft

. EPA/600/R-95/139

. Environmental Protectio n Agency (EPA)

. 1996a

. Baselin e Huma n Healt h Ris k Assessmen t Californi a Gulc h Superfun d Site

, Leadville

, Colorado

, Par t A

- Risk s t o Resident s fro m Lead

. Prepare d b y Ro y F

. Weston

, Inc

. January

. Environmenta l Protectio n Agenc y (EPA)

. 1996b

. Baselin e Huma n Healt h Ris k Assessment

, Californi a Gulc h Superfun d Site

, Leadville

, Colorado

, Par t B

- Risk s t o Resident s fro m Contaminant s Othe r tha n Lead

. Prepare d b y Ro y F

. Weston

, Inc

. January

. Environmental Protectio n Agency (EPA)

. 1996c

. Draf t EP A Fund-Lea d Projec t Plan

, Californi a Gulc h Superfun d Site,

. Prepare d b y U.S

. Burea u o f Reclamation

. February

.

1 0

### Californi a Gulc h Superfnn d Sit e Operabl e Uni t 9

/• i V \ I N / XV'NJ

V \

. 1 _.— •

Californi a Gulc h Superfun d Sit e Leadvilla

, Colorad o Transportatio n and Cultura l Feature s Hydrograph y Operabl e Uni t Boundar y RI/F S Stud y Are a Boundar y