# Repor t 34851 6 

## ADMINISTRATIV E RECOR D 

# Zin c Sla g Pil e Remedia l Investigatio n A R P8S V KEYWORD S ^ 

# a t th e Californi a Gulc h Site,
t 

# Leadville

, Colorad o FILf c 

# L (Administrativ e Orde r o n Consen t CERCLA-VIII-92-06 )

prepare d fo r 

# Denve r & Ri o Grand e Wester n Railroa d Compan y

prepare d b y 

# Morriso n Knudse n Corporatio n Environmenta l Service s Division 

# Decembe r 11,199 2FINA L REPOR T ZIN C SLA G PIL E REMEDIA L INVESTIGATIO N A T TH E CALIFORNI A GULC H SIT E LEADVILLE

, COLORAD O TABL E O F CONTENT S Executive Summar y Sectio n Titl e Pag e 1. 0 INTRODUCTIO

N 1- 1 1. 1 Purpos e o f th e Remedia l Investigatio n 1- 1 1. 2 Repor t Organizatio n 1- 2 2. 0 SIT E AN D DESCRIPTIO N 2- 1 2. 1 Sit e Descriptio n 2- 1 2. 2 Zin c Sla g Descriptio n 2- 4 2. 3 Previou s Investigation s 2- 4 3 . 0 ZIN C SLA G PIL E INVESTIGATIO

N 3- 1 3. 1 Historica l Researc h 3- 1 3. 2 Fiel d Activitie s 3- 1 3.2. 1 Reconnaissanc e

3- 2 3.2. 2 Surveyin g 3- 2 3.2. 3 Samplin g 3- 3 3. 3 Laborator y Activitie s 3- 4 3.3. 1 Compositiona l Analyse s 3- 5 3.3. 2 Leachabilit y Testin g 3- 7 3.3. 3 Physica l Testin g 3- 8 3. 4 Ai r Qualit y Investigatio n 3- 9 3.4. 1 Meteorologica l Dat a 3-1 0 3.4. 2 Emissio n Rat e Estimate s 3-1 0 3. 5 Relationshi p Wit h Other Investigatio n Program s 3-1

5 3.5. 1 ASARC O Meteorologi c Monitorin g Progra m 3-1

5 4. 0 CHARACTERISTIC

S O F TH E ZIN C SLA G PIL E 4- 1 4. 1 Smelte r Histor y and Sla g Pil e Developmen t Summar y 4- 1 4.1. 1 Brie f Histor y o f Leadvill e Smeltin g 4- 1 4.1. 2 Wester n Zin c Smelte r an d Sla g Pil e Histor y 4- 1 4. 2 Fiel d Reconnaissanc e o f th e Zinc Sla g Pil e an d Smelte r Are a 4- 2 4.2. 1 The Wester n Zin c Smelte r 4- 2 4. 3 Physica l Characteristic s 4- 2 4.3. 1 Particl e Siz e 4- 3

MORRISO N KNUDSEN CORPORATIO N BB\1883\ZINCRPT\Final-R I

i [Re v 001/13/93]TABL E O F CONTENTS

, Continue d Sectio n Titl e Pag e 

### 4.3. 2 Histori c and Curren t Zin c Sla g Pil e Surfac e Area s and Volume s 4- 4 4. 4 Sla g Pil e Stabilit y 4- 5 4.4. 1 Analysi s o f Structura l Stabilit y 4- 5 4.4. 2 Deflation/Emission s

Potentia l 4- 6 4.4. 3 Effect s o f Freeze/Tha w Cyclin g 4- 6 4. 5 Chemical Characteristic s o f Zin c Sla g Materia l 4- 7 4.5. 1 Compositiona l Analyse s 4- 8 

### 4.5. 2 Leachin g Analyse s 4-1 0 4. 6 Analytica l Dat a Validatio n 4-1 2 4.6. 1 CL P Dat a Validatio n 4-1 4 4.6. 2 Non-CL P Dat a Validatio n 4-1 5 5. 0 INTERPRETATIO

N O F RESULT S 5- 1 

### 5. 1 Statistic s 5- 1 5.1. 1 Methodolog y 5- 1 5.1. 2 Statistica l Result s 5- 2 5.1. 3 Cumulativ e Probabilit y Plot s 5- 4 5.1. 4 Statistica l Summar y 5- 5 5. 2 Potentia l fo r Wate r Qualit y Impact s 5- 5 5.2. 1 Metal s Loadin g Base d on SPL P Result s 5- 6 

### 5.2. 2 Metal s Loadin g Base d o n Colum n Leac h Result s 5- 7 5.2. 3 Metal s Loadin g Base d o n Combinatio n o f SPL P an d Colum n Leac h Result s 5- 8 5. 3 Potentia l fo r Soi l Impact s 5- 9 5. 4 Slag Pil e Stabilit y 5- 9 5. 5 Potentia l fo r Ai r Qualit y Impact s 5- 9 5. 6 Anthropogeni c

Distributio n 5-1 0 6 . 0 SUMMAR Y AN D CONCLUSION

S 6- 1 6. 1 Summar y o f Zin c Slag Characteristic s 6- 1 

### 6. 2 Conclusion s Regardin g th e Sit e Conceptua l Mode l 6- 3 7. 0 REFERENCE

S 7- 1

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Rnal-R I

H [Re v 001/13/93 ]LIS

T O F TABLE S Tabl e Titl

e 

### 3- 1 Zin c Sla g Sampl e Analysi s Summar y 3- 2 Matrix

,

Analysis

, Analytica l Method s an d Modification s an d Sampl e Siz e Requirement s 3- 3 Summar

y o f Selecte d Colorad o Hig h Countr y Statio n Annua l Precipitatio n 

### Weighte d Averag e p H Value s (NADP

, 1990 )
4- 1 Particl

e Siz e Testin g Result s 4- 2 Weigh t

Percent s o f Zinc Sla g Sample s Tha t Ar e Potentiall y Inspirabl e an d 

### Respirabl e 4- 3 Frequenc

y o f Occurrenc e - TA L Metal s 4- 4 Zin c Sla g Sampl e Aci d Formin g Potentia l 4- 5 Colum n

Leac h Tes t Result s 5- 1 Concentratio n

Range s o f Population s fo r Analyse s o f Sla g Determine d fro m Cumulativ e Probabilit y Plot s 

### 5- 2 Majo r Constituent s (mg/kg ) i n Sla g an d Subsoil s wit h Value s Assigne d t o Concentratio n Rang e Population s 5- 3 Trac e Metal s (mg/kg ) i n Sla g an d Subsoil s wit h Value s Assigne d t o Concentratio n Rang e Population s 5- 4 Miscellaneou s

Measurement s (mg/kg ) an d Sulfu r Specie s (% ) i n Sla g an d Subsoil s wit h Value s Assigne d t o Population s LIS T O F FIGURE S Figur e Titl e 1 - 1 Sit e Ma p wit h Zin c Slag Pil e Locatio n 3- 1 Zinc Sla g Pil e Sampl e Location s an d Reconnaissanc e Informatio n 

### 4- 1 Zin c Sla g Pil e Curren t Surfac e Area

, Volume

, an d Angle s o f Repos e 

### 4- 2 Zin c Sla g Pil e Histori c Volum e 4- 3 Colum n

Leac h Result s - Zin c Sla g Cation s 4- 4 Colum n

Leac h Result s - Zin c Sla g Anion s

MORRISO N KNUDSE N CORPORATIO N BB\1893\2INCRPT\F!nal- W

11 1 [Re v 001/13/93 ]APPENDI

X 

### Appendi x Titl e 

### A Fiel d Wor k Documentatio n A l Sampl e Log s B Subcontracto r

Report s B l Resourc e Technologie s Group

, Inc.

, Colum n Leac h Tes t Result s B 2 Interpro

, Inc

. Preparatio n and Siz e Analysi s Repor t C Statistic s D Calculatio n

Documentatio n D l Pil e Volum e Calculation s D 2 Pil e Metal s Loadin g Calculation s 

### E Analytica l

Documentatio n 

### E l SD G Dat a Validatio n Report s E 2 Analytica l Dat a Bas e E 3 Analytica l Dat a Packages - For m I Summar y Sheet s F Ai r Qualit y - Emissio n Rat e Estimat e Documentatio n F l Relevan t page s fro m Simi u & Scanlan

, 197 8 F 2 Tabl e 11.2.1- 1 fro m AP-4 2

MORRISO N KNUOSEN CORPORATIO N BB\1893\ZINCRFT\FinaJ-R 1

I V [Re v 001/13/93 )FINA L REPOR T ZIN C SLA G PIL E REMEDIA L INVESTIGATIO N A T TH E CALIFORNI A GULC H SIT E
EXECUTIV E SUMMAR Y
I n lat e 199 1 an d 1992 , Denve r & Ri o Grand e Wester n Railroa d Compan y (D&RGW ) 

### undertoo k a remedia l investigatio n (RI ) o f th e sla g pil e associate d wit h th e forme r Wester n 

### Zin c Smelte r withi n th e Californi a Gulc h sit e a t Leadville

, Colorado

. Lak e Count y i s th e
curren t owne r o f thi s pile

. Althoug h D&RG W ha s neve r owne d th e zin c sla g pil e or use d i t fo r an y purpose , the y agree d t o undertak e the investigatio n concurren t wit h a remedia l investigatio n fo r th e lea d sla g pile s a t th e site

. D&RG W wa s name d a Potentiall y Responsibl e Part y a t th e Californi a Gulc h sit e i n 198 6 du e t o thei r ownershi p o f thre e lea d 

### sla g piles
, whic h ha d bee n purchase d fo r us e a s railroa d ballast

. Bot h remedia l investigation s wer e performe d unde r Administrativ e Orde r o n Consent CERCLA-Vni

92006

. The purpos e o f th e R I wa s t o characteriz e th e zin c sla g pil e i n sufficien t detai l suc h tha t it s chemica l an d physica l propertie s coul d b e evaluate d fo r potentia l impact s o n huma n healt h



### an d the environment

. N o previou s investigation s o f thi s pil e ha d bee n undertake n at the sit e and
, therefore

, n o dat a existe d fo r th e pile

. Durin g th e scopin g process , dat a gap s wer e identifie d a s th e pil e siz e an d volume
, particl e sizes , geochemica l characteristics
, leachability
, 

### deflatio n potential
, an d geotechnica l stability

. R I dat a wa s collecte d t o fil l thes e gaps , a s wel l a s t o asses s th e viabilit y o f fiv e potentia l releas e mechanism s identifie d i n th e sit e conceptua l model

. Thes e fiv e releas e mechanism s include d wind
, leaching
, mixin g b y huma n activities , runof f b y particulates
, an d direc t contact

. Direc t contac t wa s discounte d i n th e baselin e huma n healt h assessment conducte d b y EPA

, leavin g fou r remainin g mechanism s t o b e evaluate d durin g thi s RI

. Th e investigatio n consiste d o f severa l majo r tasks
, includin g literatur e an d documen t review , fiel d investigatio n an d sampling
, laborator y testin g an d analysis
, an d dat a evaluatio n an d summary

.

MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Final-R I

1 [Re v 001/13/93 ]Availabl

e literatur e wa s reviewe d t o summariz e the histor y o f zin c smeltin g and sla g pil e development

. Aeria l photograph s wer e als o reviewe d t o determin e gros s change s i n volume
ove r time , indicatin g use o f th e slag

. 

### Durin g sit e reconnaissance , th e forme r smelte r sit e wa s investigate d fo r evidence o f slag
, othe r smelte r debri s or byproducts
, genera l physica l properties , and visua l indication s o f impac t t o th e surroundin g environment

. Structura l feature s o f th e pile s wer e mappe d fo r 

### inpu t t o geotechnica l stabilit y determinations an d th e pil e wa s surveye d fo r accurat e 

### calculatio n o f th e curren t pil e volume

. Indication s o f environmental impact s fro m zin c slag
, particulat e movemen t fro m precipitatio n runoff

, an d stabilit y concern s wer e no t observed

. 

### Samplin g location s wer e selecte d b y identifyin g gri d location s usin g a random numbe r generator

. Fou r discret e sample s wer e the n collecte d fro m th e surfac e t o a dept h o f 3 fee t usin g shovel s an d a backhoe

. Appropriat e qualit y assurance procedure s wer e adhere d t o 

### durin g th e samplin g phase
, a s wel l a s th e analytica l phase
, o f th e work

. Eac h o f th e sample s wa s submitte d fo r laborator y compositional
, leachability
, an d particl e siz e testing

. A portio n o f eac h sampl e wa s als o sen t t o Resurrection' s fiel d laborator y fo r incorporatio n i n th e Resurrection/ASARC O

metal s speciatio n program

. Compositiona l analyses include d tota l metals
, water-solubl e anions , an d acid-bas e accounting

. Leachabilit y testin g include d Syntheti c Precipitatio n Leachin g Procedur e (EP A Metho d 1312 ) an d 

### colum n leac h tests , whic h wer e intende d t o simulate
, a s closel y a s possible
, i n sit u conditions

. Compositiona l result s showed that the sla g i s a n iro n silicat e wit h substantia l amount s o f aluminum
, manganese , calcium
, an d zinc

. Geometri c mea n concentration s fo r th e fou r 

### primar y metal s o f concer n a t th e sit e ar e a s follows :

- Arseni c 21 1 mg/k g

- Cadmiu m 14. 1 mg/k g

- Lea d 56 8 mg/k g -Zin c 66,00 0 mg/k g 

### Th e dominant for m o f sulfu r i s sulfate

. Aci d generatio n potential
, whe n detected
, wa s mor e tha n compensate d fo r b y th e neutralizatio n potentia l du e t o th e presenc e o f carbonate

.

MORRISO N KNUOSE N CORPORATIO N BB\iea3\ZINCRPT\Flna.- K

2 IR w 001/13/93 ]

### Leachin

g analysis
, whic h include d bot h SPL P an d colum n leac h studies
, showe d minima l leachin g o f metal s o f concern
. SPL P result s for al l element s teste d i n sla g wer e below th e toxicit y characteristi c criteria , liste d i n 4 0 CF R 261.24

. Mea n value s fo r th e contaminant s
o f concer n wer e generall y tw o order s o f magnitud e lower than thes e regulator y thresholds

. Colum n leac h test s showe d similar low level s o f leaching
, althoug h studie s wer e no t continued lon g enoug h t o determin e th e stead y stat e concentration s o f lea d i n leachat e for tw o o f th e piles

. I t shoul d b e noted tha t severa l tes t desig n factor s mak e th e leachin g result s
mor e conservativ e tha n wha t i s expecte d under norma l sit e conditions

. Thes e factor s includ e th e following : Th e lixiviant use d contained non e o f th e carbonate s typicall y foun d i n natura l 

### rainwater

. Th e lixiviant wa s a sulfuric/nitri c aci d mixture whic h i s a mor e aggressiv e solution

. Th e leachin g test use d equa l period s o f we t an d dr y simulatin g a n eigh t yea r perio d o f precipitation

. Insit u condition s woul d indicat e tha t th e pile s ar e generall y dr y th e majorit y o f th e time

.


### • Leachin g o f metal s di d not begi n unti l approximatel y hal f wa y throug h the testin g perio d indicatin g tha t leachin g doe s no t begi n unti l surfac e condition s
ar e altere d t o b e conduciv e t o leaching

. SPL P leac h testing , assume d t o b e a t equilibrium
, showe d leache d metal s value s les s tha n th e maxima l value s i n cycle s a t th e en d o f th e colum n leac h 

### test

. I n sit u leachin g condition s woul d mor e closel y approximat e equilibrium

.


### • Analysi s o f subsla g material s fro m beneat h three majo r lea d sla g pile s showe d lo w value s o f metal s o f concern , indicatin g tha t an y leachin g produce d b y th e pile s ha s not severel y impacte d the material s under the piles

. The bufferin g capacit y o f th e sla g wa s stil l i n effec t at th e conclusio n o f bot h th e SPL P an d colum n leac h tests , evidence d b y th e raisin g o f pH value s fro m th e initia l 5. 0 t o greate r than 7. 0 i n th e lixiviant

.

MORMSO N KNUDSE N CORPORATIO N BB\1883\ZlNCRFT\Flnal-R I

J [R»001/13/B3 ]Particl

e siz e dat a an d site-specifi c meteorologica l dat a wer e use d t o determin e whethe r zin c sla g fine s hav e th e abilit y t o becom e airborne

. Threshol d frictio n velocitie s (th e win d spee d abov e whic h th e surfac e materia l become s airborne ) wer e calculate d usin g th e mod e o f th e 

### aggregat e siz e distribution

. Win d dat a an d the heigh t o f the pile s wer e use d t o calculat e the frictio n velocity

. Result s fo r th e pil e are : Threshol d Frictio n Velocit y 1. 0

m/se c Frictio n Velocit y 0.5

5 m/se c A frictio n velocit y lowe r tha n th e threshol d demonstrate s tha t sustaine d win d gust s i n Leadvill e are no t fas t enoug h t o caus e win d erosio n o f th e zin c slag

. A s wit h th e leachin g tests , severa l factor s buil t i n t o the calculation s mak e the result s mor e conservative tha n wha t woul d b e expecte d a t th e site

. Thes e factor s includ e th e following : I f value s mor e representativ e o f ai r flo w ove r roug h terrai n wer e use d i n the 

### calculations
, th e frictio n velocit y woul d hav e bee n lowe r tha n estimated

. Ai r density
, an d therefor e th e liftin g forc e o f th e win d at th e sam e speed
, i s 

### lowe r i n Leadville

.
• Period s o f hig h moisture , sno w cove r and froze n groun d woul d als o limi t the 

### potentia l fo r dus t emissions

. Th e result s o f th e remedia l investigatio n wer e compare d t o th e sit e conceptua l mode l develope d durin g th e scopin g process

. O f th e fiv e potentia l releas e mechanism s fo r wast e pile s (wind

, leaching
, mixin g b y huma n activities , runof f o f particulates
, an d direc t contact)

, 

### onl y leachin g o f metal s throug h contact wit h precipitatio n o r othe r sit e water s wa s retaine d

a s viabl e fo r zin c sla g pile s withi n th e Californi a Gulc h site

.

MORNSO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Flnal-R I

4 [Re v 0 01/13/93 ]FINA L REPOR T ZIN C SLA G PIL E REMEDIA L INVESTIGATIO N A T TH E CALIFORNI A GULC H SIT E LEADVILLE

, COLORAD O

1. 0 INTRODUCTIO

N 

### Thi s documen t present s th e result s o f th e Zin c Sla g Pil e Remedia l Investigatio n (RI ) a t th e 

### Californi a Gulc h Superfun d sit e a t Leadville

, locate d i n Lak e County

, Colorado

. The repor t

wa s prepare d b y Morriso n Knudse n Corporatio n (MK ) fo r th e Denve r an d Ri o Grand e 

### Wester n Railroa d Compan y (D&RGW ) i n complianc e wit h Administrativ e Orde r o n Consen t (AOC ) CERCLA-VIII-92-06

.

D&RG W wa s name d a s a Potentiall y Responsibl e Part y i n 1986 (Civi l Actio n No

. 86-C-1675

, Unite d State s Distric t Court

, Stat e o f Colorado ) du e t o their ownershi p o f thre e lea d sla g pile s i n th e Californi a Gulc h that ha d bee n purchase d for us e a s railroa d ballast

. Althoug h D&RG W doe s no t ow n th e zin c sla g pil e 

### i n Leadville

, no r us e i t fo r an y purpose , the y hav e investigate d i t a s par t o f a n overal l R I f o r sla g pile s withi n th e Californi a Gulc h site

. The Zinc Sla g Pil e R I wa s performe d concurren t wit h the Lead Sla g Pil e R I i n accordanc e wit h th e Work Pla n fo r Slag Pil e Remedia l Investigatio n a t Californi a Gulc h Sit e (MK

, 1991a ) an d th e Samplin g an d Analysi s Pla n fo r Sla g Pil e Remedial Investigatio n a t 

### Californi a Gulc h Sit e Pla n (MK

, 1991b)

. 1. 1 Purpos e o f th e Remedial Investigatio n Th e purpos e o f th e R I wa s t o characteriz e th e singl e zin c sla g pil e locate d withi n th e Californi a Gulc h sit e i n sufficien t detail suc h tha t it s chemical
, physical
, an d mineralogica l propertie s coul d b e evaluate d for potentia l impact s on huma n healt h an d th e environment

. 

### The R I fill s dat a gap s relatin g t o pil e siz e an d volume
, sla g particl e sizes, geochemica l characteristics
, teachability
, deflatio n potential
, an d geotechnica l stability

. Th e scop e o f thi s remedia l investigatio n includes onl y th e zin c sla g pil e associate d wit h th e Wester n Zin c Smelter

. I t i s ofte n referre d t o a s th e Hig h Schoo l pile
, base d o n it s locatio n (Figur e 1-1)

, or th e Count y pile
, base d on it s ownershi p b y Lak e County

. D&RG W ha s als o 

### investigate d th e majo r lea d smelter-derive d sla g pile s withi n th e Californi a Gulch site

. A s th e lea d sla g (MK

, 1992 ) i s distinctl y differen t fro m zin c slag
, th e R I report s hav e bee n submitte d separately

. MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Rnal-R I

1- 1 (Re v 001/13/93 ]HISTORI C SMELTE R LOCATIO N RI/F S SIT E BOUNDAR Y
ZIN C SLA G VENEE R O R SCATTERE D ZIN C SLA G PIECE S SAMPL E LOCATIO N

CALIFORNI A GULC H CERCL A SIT E ZIN C SLA G PIL E INVESTIGATIO N LJADVIUE

, COLORAD O SITE MA P WIT H ZIN C SLA G PIL E LOCATIO N DENVE R & RI O CRAND E WESTER N RAILROA D DENVER

. COLORAD O NOTE : TOPOGRAPHI C CONTOUR S AN D SURFAC E FEATURE S DIGITIZE D B Y INTRASEARC H FRO M 199 0 AERIA L PHOTOGRAPH Y AN D PROVIDE D B Y RO Y F

. WESTON

. INC

. MORRISON-KNUDSE N

CORPORATIO N FII I NAU C (CM) ) 1B93N054/XR89303 9

IDATtJ/M/9 21. 2

Report Organizatio n Thi s repor t i s organize d t o presen t RI fiel d an d laborator y activit y summaries , dat a validation
, analytica l result s an d interpretations , an d conclusions

. Sectio n 2. 0 present s a n overvie w o f sit e conditions

. N o previou s investigation s hav e bee n conducte d for th e zin c sla g a t th e sit e and
, therefore

, n o historica l informatio n i s include d i n thi s section

. Th e scop e o f th e Zin c Sla g Pil e Remedia l Investigation

, includin g al l field

, laboratory
, an d dat a analysi s activities , i s presente d i n Sectio n 3.0

. Sectio n 4. 0 present s th e physica l an d chemica l characteristic s o f th e zin c sla g pil e determine d durin g th e RI

, and Sectio n 5. 0 present s an interpretatio n o f thes e results

. Sectio n 6. 0 present s the summar y an d conclusions

. Sectio n 7. 0 contain s references

. Th e appendice s provid e fiel d documentation
, th e analytica l database
, dat a validatio n reports , summar y sheet s o f laborator y dat a packages
, calculatio n documentation
, an d statistica l analysi s backup

.

MORRtSO N KNUOSE N CORPORATIO N BB\1893\ZINCRFT\Final-R I 1- 2 [Re v 001/13/93 ]2 . 0

SIT E AN D DESCRIPTIO N T h e followin g descriptio n o f th e Californi a Gulc h sit e include s a brie f histor y o f th e Leadvill e minin g district
, a general descriptio n o f th e physiographi c an d hydrologi c 

### propertie s o f the site , an d a descriptio n o f zin c slag

. Sit e informatio n presente d i n thi s sectio n i s summarize d primaril y fro m studie s performe d prio r t o th e 1991-199 2 remedia l investigatio n work

. 2. 1 Sit e Descriptio n Th e Californi a Gulc h sit e ha s experience d ove r 13 0 year s o f minin g and smeltin g activity

. 

### The sit e encompasses the tow n o f Leadville

, Colorado

, whic h i s approximatel y 10 0 mile s southwes t o f Denve r a t a n elevatio n o f 10,00 0 fee t abov e mea n se a level

. Silver

, gold
, copper , lead
, and zin c wer e mine d b y undergroun d and place r method s fro m the majo r sulfide/carbonat e or e deposi t i n th e Leadvill e Minin g District

. Approximatel y 1 7 smelter s


### ar e reporte d t o hav e operate d here

. Onl y a fe w small

- t o moderate-size d minin g operation s
no w exis t an d n o smelter s currentl y operat e i n Leadville

. 

### Th e mai n mining-relate d feature s i n th e Leadvill e are a toda y includ e th e following : Tailing s impoundment s Sla g pile s Mor e tha n tw o thousan d wast e roc k dump s 

### Abandone d mine , milling
, an d smeltin g facilitie s A fe w active minin g an d reprocessin g operation s • Min e wate r drainag e tunnel s Th e Ya k Tunnel

, whic h drain s int o Californi a Gulch

, wa s th e mai n point-sourc e discharg e
o f acidi c metal-lade n wate r t o Californi a Gulc h befor e treatmen t plan t operation s bega n i n 

### 1992

. Thi s tunnel drain s undergroun d minin g area s eas t o f Leadville

. I n 1983 , th e Californi a Gulc h sit e wa s place d o n th e EPA' s Nationa l Prioritie s Lis t becaus e o f heav y metal s loadin g t o th e Arkansa s River

. Climatolog y 

### Th e climat e o f th e Leadvill e are a i s typica l o f mountainou s area s i n centra l Colorado

. Th e
are a ha s extrem e temperatur e change s fro m summe r t o winte r an d i n an y seaso n ca n experienc e rapi d change s o f weathe r cause d b y storm s travellin g primaril y fro m wes t t o east

. Loca l topographi c feature s strongl y influenc e climati c variation s i n th e stud y area
. Averag e
MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Final-R l

2- 1 [Re v 001/13/93 ]

### annua

l precipitatio n i s 12.6 7 inche s (Res-Asarco

, 1991)

. Jul y an d Augus t hav e th e mos t precipitation , an d Decembe r an d Januar y hav e th e least

. Summertim e precipitatio n i s usuall y associate d wit h convectiv e showers

. Precipitatio n occur s sporadically
, causin g 

### occasiona l flas h floods

. Annua l snowfal l depth s fo r mountain s i n th e are a rang e betwee n 20 0 an d 30 0 inches

. Durin g winte r months
, th e dept h o f sno w o n th e groun d i n Leadvill e i s commonl y 6 inches

. Th e precipitatio n an d temperatur e cycle s giv e ris e t o a n annua l pea k 

### runoff

, usuall y occurrin g durin g June

. Th e temperatur e extreme s rang e fro m 8 6° F t o -3 0° F

, wit h a n averag e minimu m dail y temperatur e o f 21. 9° . Th e averag e frost-fre e seaso n i s 79 days

. Win d i s predominatel y fro m th e northwes t (CDL

, 1986)

. Geolog y 

### Th e geolog y o f th e Leadvill e Minin g Distric t i s complex

. Bedroc k consist s o f th e 

### Precambrian crystallin e rock s overlai n b y quartzites , shales
, limestones
, dolomites
, an d sandstone s o f th e Paleozoic era
. Numerou s fault s exist a t th e easter n edg e o f th e site , rangin g i n widt h fro m severa l fee t t o hundred s o f feet

. Severa l episode s o f faulting

, bot h pre-mineralizatio n an d post-mineralization
,

hav e bee n documente d (EPA

, 1989c)

. T h e primar y mineral s deposite d b y hydrotherma l solution s wer e predominantl y sulfide s o f 

### iron , zinc , an d lead
, bu t als o include d copper , silver
, an d gold

. Late-Tertiar y tectoni c activit y faulte d the mineralize d zone s int o block s and expose d the m t o oxygenate d groun d waters

. Sulfid e mineral s wer e oxidized
, forme d sulfuri c acid
, an d release d metal s int o 

### solution

. Thes e solution s wer e transporte d t o carbonat e zones , wher e precipitatio n reaction s
occurre d betwee n th e mineralize d sulfuri c aci d solution s an d th e carbonat e rock

. Thi s depositio n zon e o f secondary
, o r remobilized
, mineral s i s terme d the oxidize d zone
. The resultin g carbonat e ore s forme d th e dominan t or e zone s i n man y o f th e area' s earl y mine s (EPA

, 1989c)

. The chang e i n geolog y i s significan t wes t o f th e Pendr y Fault

, whic h i s ofte n use d t o demarcat e uppe r fro m lower Californi a Gulc h an d i s locate d a t th e eastern edg e o f Leadville

. Abov e the fault

, Precambria n crystallin e rock s ar e a n upthrus t relativ e t o stratigraphi c unit s o f sediment s o r alluvium

. Below th e fault

, thre e identifiabl e geologi c unit s ar e noted : bedrock
, lak e be d sediments
, and high-terrac e gravels

. Th e thicknes s o f th e uppe r an d middl e stratigraphi c unit s (gravel s an d lak e bed sediments ) increase s fro m eas t 

### t o west

. The uppe r uni t varie s i n thickness fro m approximatel y 5 0 fee t nea r the Pendr y Faul t t o severa l hundre d fee t nea r th e Arkansas River

. Place r operation s and min e wast e

MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Rnal-R I

2- 2 [Re v 0 01/13/93 ]

### disposa l

probabl y altere d the surfac e an d near-surfac e feature s o f the high-terrac e gravel s stratigraphi c uni t (EPA

, 1989c)

. Groun d Wate r 

### Th e comple x geolog y i n th e uppe r Californi a Gulch are a ha s a significan t impac t on ground



### wate r movement

. Groun d wate r occur s i n bot h bedroc k an d alluvia l systems , an d recharg e i s principall y fro m infiltratio n o f snowmel t and rainfall

. Groun d wate r migratin g throug h the bedroc k syste m eas t and southeas t o f Leadvill e discharge s directl y t o Californi a Gulc h surfac e waters , int o min e working s an d th e Ya k Tunnel

, o r int o downgradien t bedroc k o r alluvia l ground-wate r system s (EPA

, 1989c)

. I n lowe r Californi a Gulch

, ther e i s an activ e interchang e between th e shallo w ground-wate r 

### syste m an d th e surfac e water

. Therefore

, a pathwa y exist s fo r meta l contaminant s originatin g fro m th e Ya k Tunnel

, or other source s tha t contribut e t o surfac e wate r 

### contamination , t o affec t ground-wate r quality

. Ground-wate r qualit y i s strongl y influence d b y depth
, wit h th e poores t qualit y foun d a t th e shallowes t depths

. Generally

, th e highes t meta l concentration s ar e withi n 2 5 t o 5 0 fee t o f th e surfac e (EPA

, 1989c)

. Surfac e Wate r 

### The Californi a Gulc h sit e encompasse s abou t 1 5 squar e mile s o f surfac e wate r drainag e upstrea m fro m th e confluenc e o f Californi a Gulc h wit h th e Arkansa s River

. Th e mai n ste m 

### o f Californi a Gulc h flow s eas t t o west , jus t sout h o f Leadville

, an d drain s wate r fro m severa l smal l tributaries t o th e nort h an d south

. Th e Stray Hors e Gulch/Star r Ditc h watershe d i s th e larges t subbasi n an d drain s land s extensivel y affecte d b y minin g operations

. Al l 

### tributarie s t o Californi a Gulch

, a s wel l a s th e uppe r Californi a Gulc h itself

, ar e ephemeral drainages

. Californi a Gulch receive s flow s fro m tw o continuou s point-sourc e discharges : th e 

### Ya k Tunne l treatmen t plan t a t 1 t o 2 cubi c fee t pe r secon d (cfs)

, an d th e Leadvill e 

### wastewate r treatmen t plan t at approximatel y 1 cf s (EPA

, 1989c)

. Annua l flow s i n bot h th e Arkansa s Rive r an d Californi a Gulc h ar e normall y highes t i n th e sprin g durin g snowmel t an d lowes t i n th e fal l an d winter

. Loca l summe r thunderstorm s are , however
, capabl e o f producin g high-intensity
, short-duratio n flow s i n th e Gulch

. Floodin g 

### potentia l i n th e Gulch i s hig h becaus e o f lac k o f vegetativ e cover
. Maximum floo d 

### conditions i n th e are a ar e expecte d i n th e May-Jun e snowmel t perio d (EPA

, 1989c)

.

MORRMO N KNUDSE N CORPORATIO N B8\1883\ZINCRPT\Fina!-R I

2- 3 [ R w 001/13/93 ]Accordin

g t o previou s data
, wate r qualit y i n th e uppe r Arkansa s Rive r i s degrade d belo w th e discharg e fro m th e Leadvill e Drainag e Tunnel

, markedl y degrade d belo w Californi a 

### Gulch

, an d improve d b y th e clean wate r inflo w fro m creek s furthe r downstream

. Th e 

### highes t meta l concentration s occu r i n th e sprin g durin g snowmelt

. Durin g th e 1984 , 1985 , an d 198 7 investigations b y EPA

, primar y drinkin g wate r standard s fo r cadmium an d lea d

wer e commonl y exceeded
, a s wer e th e Aquati c Wate r Qualit y Criteri a (AWQC ) fo r 

### cadmium
, copper , lead
, an d zin c (EPA

, 1989c)

. 2 2 Zin c Sla g Descriptio n 

### Sla g i n the vicinit y o f the Wester n Zin c Smelte r are a i s a mineralize d by-produc t resultin g 

### fro m th e volatilizatio n o f zin c fro m zin c oxid e and carbonat e ore s i n a Wetheril l furnace

. I n thi s furnace

, briquette s o f ore and anthracit e wer e fe d ont o fue l burnin g on a cast-iro n grate

. A zin c vapo r evolve d and wa s subsequentl y oxidized

. The fumes

, generall y zin c oxide
, wer e collecte d i n th e baghous e a s th e smeltin g product

. Th e zin c smelte r by-product s
ar e scoriaceou s slag
, coa l clinker
, and ash

. The sla g i s a highl y vesicula r material
, ofte n wit h



### a yello w o r reddis h oxid e rind

. Th e specifi c gravit y o f th e zin c sla g resultin g fro m th e Wetheril l proces s i s notabl y les s tha n tha t o f lea d slag
, likel y du e t o th e vesicles forme d b y 

### th e expansio n o f gases

. Th e sla g typicall y contain s approximatel y 1 6 percen t iro n an d 1 4 percen t silicon
, substantia l amount s o f aluminum
, manganese , calciu m an d zinc , a s wel l a s trace s o f othe r residua l bas e metals

. Figur e 1- 1 i s a ma p o f the sit e tha t show s the histori c zin c smelte r locatio n and the sla g pil e sample d unde r thi s RI

. Th e genera l characteristic s an d histor y o f thi s sla g pil e ar e discusse d i n followin g sections

. 2. 3 Previou s Investigation s 

### Severa l previou s investigations a t th e Californi a Gulc h sit e hav e addresse d lea d slag ; however
, n o existin g dat a i s availabl e fo r th e Wester n Zin c sla g pile

.

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Final-R I

2- 4 [Re v 001/13/93]3 . 0 ZIN C SLA G PIL E INVESTIGATION 

### Th e Zin c Sla g Pil e R I consisted o f literatur e research
, fiel d investigation , and laborator y analyses

. Historica l researc h wa s performe d relatin g t o the developmen t o f the Wester n Zin c smelte r an d it s associated sla g pile

. Fiel d activitie s include d inspecting , surveying , an d samplin g th e pile

. Laborator y activitie s include d compositional
, teachability
, an d physica l testin g o f the sla g and subsla g samples

. The sample s wer e also submitte d t o the metal s speciatio n progra m undertake n b y ASARC O and Resurrectio n Minin g Corporation

, othe r PRP s a t th e Californi a Gulc h site

. 3. 1 Historica l Researc h Availabl e literatur e wa s reviewe d t o summariz e th e histor y o f Leadvill e are a smelter s an d the developmen t o f associate d sla g piles

. The ke y resourc e fo r thi s summar y wa s Historical Mineral Processing Operations o f th e Leadville Mining District, (EPA

, 1991)

, a repor t o f 

### historica l smelte r an d millin g operation s prepare d fo r th e sit e b y Jacob s Engineerin g Group

. Othe r reference s reviewe d include : Leadville: Colorado's Magic City, b y Edward Blair

. Pruet t Publishin g 

### Company

, Boulder

, Colorado

, 1980

. Draft Remedial Investigation Scoping Document California Gulch Site, 

### Leadville

, Colorado

, Prepare d b y Woodward-Clyd e Consultant s fo r Res

- ASARC O Join t Venture

, Apri l 1991

. Ores t o Metals, b y Jame s E

. Fell

, Jr.

, Universit y o f Nebrask a Press

, Lincoln

, Nebraska

, 1979

. 3 2 Fiel d Activitie s 

### Th e Zin c Sla g Pil e R I activitie s include d fiel d reconnaissance t o describ e th e Wester n Zin c sla g pil e an d material s i n th e vicinit y o f th e pile

. Additionally

, th e pil e wa s surveye d t o documen t it s siz e an d location

. Sample s wer e obtaine d fro m location s randoml y selecte d fro m a gri d syste m establishe d fo r th e pile

.

MORM80 N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Fln«l-R I

,?- ! [Ra w 001/13/93]3.2. 1

Reconnaissance Severa l decade s o f aeria l photograph y wer e use d t o assis t i n identifyin g th e gros s 

### characteristic s o f th e smelte r an d sla g area
. A summar y o f th e photograph y reviewe d i s a s follows : Dat e Agenc

y Projec t

Scal e Rol l Fram e

Number s 9-23-5 6 Fores t Servic e DZ

Z 1:20,00 0 6

122-12

4 9-21-5 8 Fores t Servic e DZ

Z 1:20,00 0 2 1 30-3

2 9-23-6 4 USG S GS-VAX

S 1:31,50 0 1

156,157,161,16

2 8-31-7 5 Fores t Servic e 0806

5 1:15,84

0 97

4 068,069,095,09 6 9-4-7 6 Fores t Servic e 0806

5 1:15,84 0 1,27

5 187,18 8 8-27-9 0 Intrasearc h Denve r 9014 5 1:14,40 0 90,14 5 9-11

, 22-2 4 Th e histori c smelte r locatio n wa s visite d b y a n M K geologis t an d fiel d enginee r o n Ma y 11 , 

### 1992

. The sla g pil e wa s describe d fo r physica l propertie s suc h a s size , color
, genera l particl e size , texture , an d sign s o f weathering

. Th e pil e wa s photographe d an d plotte d on th e bas e topographi c ma p o f the site

. Proximit y o f the pil e t o residence s o r othe r structures , streams , 

### ephemera l runof f channels
, an d othe r smelter

- o r mining-relate d waste s o r structura l debri s


### wa s noted

. Additionally

, an y evidence o f sla g impactin g the surroundin g environment , suc h

a s fine s transporte d fro m th e pil e b y win d o r water , stresse d vegetation , an d iro n stainin g 

### wa s noted

. Th e zin c sla g pil e structura l feature s wer e observe d fo r beddin g an d layering
, includin g 

### thickness an d orientation

. Th e presenc e o f fracture s o r crack s wa s investigated
, alon g wit h



### an y conditions tha t might hav e indicate d bloc k movemen t eithe r b y rotatio n o r norma l faulting

. An y talu s a t th e bas e o f sla g pil e wa s note d an d angle s o f repos e wer e determine d t o asses s slop e stability

. Surveyin g 

### Th e Wester n Zin c sla g pil e wa s surveye d b y a professiona l surve y tea m o n Ma y 11 , 1992 , 

### afte r th e Decembe r 199 1 samplin g effort

, becaus e sno w cove r prohibite d accurat e surveyin g
at the tim e o f sampling

. The surve y wa s performe d t o allo w the additio n o f sla g pil e 

### contour s t o th e existin g bas e ma p an d calculatio n o f th e pil e volum e t o withi n approximatel y 1 0 percen t error
. Elevationa l dat a for th e sla g pil e perimeter , to p an d toe, an d grad e break s
wer e determine d so tha t th e pil e height
, sid e slope s an d volum e coul d b e calculated

. A dat a fil e o f the coordinate s fo r eac h poin t surveye d wa s use d i n conjunctio n wit h AutoCA D t o 

### develo p contour map s o f th e pil e an d integrat e the m int o th e existin g bas e map

. Volume s
wer e als o calculate d usin g th e AutoCA D software

, AutoCOGO

. MORRMO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\F1n«l-R !

3- 2 fFtoiO 01/13/93 ]3.2.

3 Samplin g Zin c sla g pil e samplin g wa s performe d o n Decembe r 4 , 1991

. The detail s o f the samplin g procedure s ar e presente d i n th e Samplin g an d Analysi s Pla n (SAP ) (MK

, 1991b)

. N o variance s fro m thes e procedure s wer e require d a t th e Wester n Zin c Pile

. 3.2.3. 1 Sampl e Location s Th e sampl e locations wer e randoml y selecte d on a rectangula r gri d syste m overlai n on map s


### o f th e sla g pile

. Thi s procedur e fo r selectin g random sampl e locations i s provide d i n Methods fo r Evaluating th e Attainment o f Cleanup Standards (EPA

, 1989b ) an d th e bas e ma p wit h th e superimpose d gri d syste m i s provide d i n th e SA P (Sectio n 3.0 , M K 1991b)

. 

### Fou r discret e sampl e location s wer e selecte d usin g a random numbe r generato r t o identif y cel l number s withi n th e gri d syste m (MK

, 1991b)

. Th e cell s wer e the n locate d i n th e fiel d 

### b y tap e and/o r pac e compas s traverse s fro m recognize d point s o n th e bas e maps

. Sample s
wer e collecte d fro m the cente r o f a gri d cell

. Generally

, cell s that occurre d entirel y o n a portio n o f th e sla g pil e tha t ha d a sla g thicknes s greater tha n thre e fee t an d wer e accessible
, 

### wer e sampled

. On e cel l a t th e Wester n Zin c pil e di d no t mee t th e thicknes s criteria , an d

a n alternat e cel l wa s randoml y selected

. Th e sampl e location s ar e depicte d o n Figur e 3-1

. Photograph s o f eac h locatio n wer e take n


### and the sla g pil e feature s wer e note d i n the lo g book

. 3.2.3. 2 Surfac e Slag Samplin g Procedure s The fou r sla g sample s wer e obtaine d wit h a backhoe
, ove r a 0

- t o 3-foo t dept h range
. The initia l sampl e siz e collecte d wa s 40 0 pounds

. Thi s sampl e siz e wa s base d o n recommendation s fro m Standard Practice fo r Sampling Aggregates, AST M Metho d D-75

, (ASTM

, 1992b)

. 

### Eac h sampl e wa s place d o n a hig h densit y polyethylen e (HDPE ) shee t and a sampl e homogenizin g procedur e wa s performe d b y successivel y liftin g eac h corne r o f th e HDP E an d rollin g th e sampl e ove r itself

. Thi s wa s performe d repeatedl y unti l th e sampl e wa s thoroughl y mixed

. 

### Th e sampl e wa s the n pile d int o th e shap e o f a cone , flattened

, an d divide d int o quarter s usin g plasti c shovels

. On e quarte r wa s randoml y selecte d and
, alon g wit h it s opposit e quarter , collecte d fo r laborator y testin g an d analysis

. MORRISO N KNUOSE N CORPORATIO N 88\1893\2INCRPT\Final-R I

3- 3 [Re v 001/13/93 )N

515,00 0 -

N 514,50 0

j ACCES S KOW,____

_ j

_ _ ____ / 

### LEGEN D SURFAC E CONTOU R INTERVA L 2 BUILDIN G A HSS10 1 SAMPL E LOCATION S A N D IDENTIFICATIO N SMELTE R RUBBL E ARE A NOTE : TOPOGRAPHI C CONTOUR S AN D SURFAC E FEATURE S DIGITIZE D B Y INTRASEARC H FRO M 199 0 AERIA L PHOTOGRAPH Y AN D PROVIDE D B Y RO Y F

. WESTON

, INC

.

5 0 SCAL E FEE T 10 0 15 0
1"=100 20

0

LAK E COUNT Y HIG H SCHOO L

CALIFORNI A GULC H CERCL A SIT E ZIN C SLA G PIL E INVESTIGATIO N LEADVILLE

, COLORAD O FIGUR E 3- 1 ZIN C SLA G PIL E SAMPL E LOCATION S A ND RECONNAISSANC E INFORMATIO N DENVE R & RI O GRAND E WESTER N RAILROA D ______DENVER

.

COLORADO_____

_ ( 6 & MORRISON-KNUDSE N

CORPORATIO N FIL E NAM E (CAD ) 1893N01 4 PROJEC T SUFFI X TAS K 189 3 63 0 06-90 0 lD»TE:9/06/9 1

DRAWIN G NUMBE R FIGUR E 3- 1 REV

. A

### Eac

h sampl e fo r testin g an d analysi s wa s place d i n tw o five-gallo n bucket s an d on e one
gallo n bucket

. The bucket s wer e seale d and labele d wit h identificatio n numbers

. A t the 

### en d o f eac h day
, al l sample s wer e transporte d t o a locke d she d fo r shipmen t t o th e sampl e preparatio n an d splittin g laboratory

. 3.2.3. 3 Decontaminatio n

Procedure s Decontaminatio n wa s performe d t o preven t cross-contaminatio n

o f samples

. Samplin g tool s 

### suc h a s shovels
, trowels
, an d plasti c bucket s wer e initiall y cleane d b y mechanicall y removin g an y loos e materials

. Next

, th e equipmen t wa s scrubbe d wit h a non-phosphat e detergen t 

### (Alconox ) an d wate r solutio n unti l n o visibl e materia l remained
, an d the n rinse d wit h ta p wate r an d deionize d water

. HDP E sheet s an d part s o f heav y equipmen t i n contac t wit h sla g
wer e decontaminate d wit h a hig h pressure , ho t wate r sprayer , an d the n rinse d wit h deionized water

. Decontaminatio n

wa s performe d a s clos e a s practica l t o th e associate d sampl e 

### locatio n an d spen t wate r wa s discarde d o n th e ground

. On e equipmen t rinsat e sampl e wa s collecte d t o verif y tha t th e decontaminatio n procedures wer e adequate

. Samplin g equipmen t wa s store d i n clean plasti c bag s afte r ai r drying

. Clea n tool s and HDP E sheet s


### wer e use d fo r eac h sampl e location

. Laborator y Activitie s 

### Sample s wer e transmitte d t o th e laboratorie s under chain-of-custod y protocol

. Laborator y activities wer e performe d a s specifie d i n th e SA P (MK

, 1991b)

. Chemica l analyse s include d 

### bot h compositiona l an d leachabilit y testing

. Physica l analyse s wer e performe d t o determin e th e particl e siz e distributio n o f th e zin c sla g material

. Tabl e 3- 1 present s th e analyse s 

### performe d on th e zin c sla g samples

. Tabl e 3- 2 summarize s th e analytica l method s an d sampl e siz e requirements

. Sampl e preparatio n an d particl e siz e determinatio n wer e performe d b y Interpr o o f Golden

, Colorado

. Silve r Valle y Laboratories

, Inc

. (SVL ) o f Kellogg

, Idah o performe d 

### compositiona l an d Syntheti c Precipitatio n Leachin g Procedur e (SPLP ) testing

. Th e colum n 

### leac h tes t wa s performe d b y Resourc e Technologie s Grou p (RTG)

, Whea t Ridge

, Colorado

. Eluat e fro m th e colum n leac h tes t wa s analyze d b y SVL

. Prepare d zin c sla g sample s wer e 

### als o submitte d t o Resurrectio n Minin g Corporatio n a t thei r Leadville

, Colorad o fiel d offic e fo r analyse s unde r Final Work Plan

- Metals Speciation an d Source Characterization a t California Gulch CERCLA Site Work Plan (Resurrection

, 1992)

.

MORMSO N KNUD8E N CORPORATIO N BB\1893\ZINCRPT\Flnal- W

3~ 4 [Re v 001/13/83]

### TABL E 3- 1 

### ZIN C SLA G SAMPL E ANALYSIS SUMMAR Y
SAMPL E NO

. COMPOSITIONA L

ANALYSE S LEAC H

TEST S PHYSICA L ANALYSE S

. m o m N *

~ Z v
. tn C O 3 C O

— •> t

- o

### Tabl e 3- 2

Matri x Analysi

s Typ e Analytica l

Metho d Referenc e Sampl

e Siz e Modification s Zin c Sla g Tota l

Metal s Digestio n CL

P SO W 03/9 0 Burea u o f Mbe s D3683-7 8 CL P SO W AST M 10

0 gram s Ad d Silicon

, delet e Mercur y Mor e Rigorou s Disgestio n Zin c Sla g Rainfal

l Shak e Metho d

131 2 SW-84 6 100

0 gram s N o Particl e Siz e Reductio n Increas e Sampl e Siz e Zin c Sla g Sulfu r

form s Neutralizatio n Potential Catio n Exchang e Capacit y 3Z4/3.2. 6 3.2. 3 ER A 908 0 EP

A 600/2-78-05 4 EPA600/5-78-05 4 SW-84 6 50

0 gram s Analysi s Performe d o n Water-Solubl e Fractio n o f Material Zin c Sla g Anion K

CT

, SO* * NO» NO'

, Metho d

300.0/310. 1 followin g wate r soi l extractio n EP

A 600/4-7 8 50 0 gram s Non e Zin c Sla g Particl

e Siz e Analysi s Seiv e Analysi s Hydromete r Microtrac ASTMD42 2

ASTMD42 2 Varie

s Microtra c

t o augmen t hydromete r

### Sampl

e Preparatio n an d Laborator y Submitta l 

### Th e bul k sample s o f zin c slag
, wit h th e exceptio n o f th e SPL P an d th e colum n leac h sample
, wer e delivere d t o Interpr o o f Golden

, Colorad o fo r sampl e preparation

. Th e SPL P sample s
wer e forwarde d immediatel y t o SV L fo r analysi s withou t particl e siz e reductio n o r othe r 

### preparation

. A t Interpro

, sampl e preparatio n wa s precede d b y particl e siz e analysi s o f th e 

### samples

. Afte r th e particle-siz e determinations wer e performed

, th e seive d material s wer e recombine d i n th e origina l sampl e container

. Th e entir e sampl e wa s crushe d t o minu s 3
mes h (6.7mm ) wit h a ja w crushe r an d a rol l crusher

. Th e minu s 3 mes h materia l wa s blende d an d a 10

- t o 11

- poun d sampl e wa s spli t fro m th e mixture

. Thi s sampl e spli t wa s furthe r reduced i n a plat e pulverize r t o minu s 6 0 mes h (25 0 microns)

. Th e pulverize d 

### sampl e wa s the n blende d an d spli t int o 1-pound samples
, eac h place d i n a glas s bottle
, labeled
, an d sealed

. Th e 1-pound
, minu s 250 micro n prepare d sample s wer e submitte d t o S V L an d intereste d partie s fo r analysis

. Interpr o has archive d pulverize d sample s (1-poun d jars ) and unprepare d 5-gallo n bucket s o f eac h sample

. 3.3. 1 Compositiona l Analyse s Compositiona l analyses wer e performe d t o determin e th e bul k chemistr y o f th e zin c slag

. Th e compositiona l analyse s include d th e following : 

### Tota l Metal s Anion s Aci d Formin g Potentia l includin g al l Sulfu r Form s 

### Neutralizatio n Potentia l • Catio n Exchange Capacit y
3.3.1. 1 Tota l Metal s Tota l metal s wer e determine d fo r th e zin c sla g sample s b y inductivel y couple d plasm a (ICP )

an d graphit e furnac e atomi c absorptio n (GFAA)

. Analyse s wer e performe d accordin g t o method s describe d i n th e Contract Laboratory Program Statement o f Work fo r Inorganics Analysis (SO W 4/90 ) (EPA

, 1990a)

. A s the metho d fo r tota l digestio n i n SO W 4/9 0 i s not 

### rigorou s enoug h t o completel y diges t th e sla g matrix , th e U.S

. Burea u o f Mine s digestio n 

### metho d wa s use d fo r sampl e preparatio n a s reporte d i n A Simple Low-Cost Method fo r th e Dissolution o f Metal an d Mineral Samples i n Plastic Pressure Vessels (Burea u o f Mines

, 1980)

.

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3- 5 [Re v 001/13/93 ]

### Th e U.S

. Burea u o f Mine s digestio n metho d use s mor e reactiv e reagents

. Thi s digestio n method i s include d i n Appendi x H o f th e Sla g Pil e SA P (MK

, 1991b)

. Eac h sampl e wa s prepare d fo r Targe t Analyt e List (TAL ) metal s analysi s accordin g t o procedure s require d b y SO W 4/90

. Th e sampl e i s initiall y crushe d an d mixe d thoroughly

. 

### A representativ e one-gra m subsampl e i s the n digeste d usin g th e U.S

. Burea u o f Mine s 

### digestio n method wit h hydrofluori c acid
, nitri c aci d an d hydrochlori c acid

. Afte r th e digestat e i s boile d an d cooled
, bori c aci d i s added

. Th e solutions are the n rebelled
, coole d

an d analyzed

. Arsenic

, lead
, an d seleniu m wer e measure d b y GFAA

. Th e concentration s
o f th e remainin g analytes (aluminum

, antimony , barium
, beryllium
, cadmium
, calcium
, 

### chromium
, cobalt
, copper , iron , magnesium , manganese, nickel
, potassium , silicon
, silver
, sodium
, thallium
, vanadiu m an d zinc ) wer e measure d b y ICP

. Mercur y concentration s wer e no t determined
, a s specifie d i n th e SA P (MK

, 1991b)

. 3.3.1. 2 Anion s 

### Metho d 300.1/310. 1 (EPA

, 1982 ) followin g water/soi l extractio n wa s use d t o determin e th e 

### followin g anion s i n th e zin c sla g material : Chlorid e Sulfate Nitrate/Nitrit e 

### Anion s wer e analyze d t o determin e concentration s for input t o geochemical modelin g and

a s corroboratio n wit h metal s speciatio n results

. 3.3.1. 3 Sulfu r Form s Potentia l acidit y o f zin c sla g wa s determine d fo r eac h sampl e b y measurin g sulfu r 

### concentration s accordin g t o EP A Metho d 3.2. 4 fro m Field an d Laboratory Methods Applicable t o Overburdens an d Minesoils EPA-600/2-78-05

4 (EPA

, 1978)

. A les s tha n 6 0


### mes h sla g sampl e i s heate d a s oxygen i s passe d throug h th e sample

. A starc h solution
, whic h collect s th e sulfu r dioxid e a s i t i s released
, i s the n titrate d an d th e percent tota l sulfu r 

### calculate d base d o n th e startin g mas s an d th e titratio n measurement

. I f al l o f th e sulfu r occur s i n pyritic forms

, th e calculatio n o f maximu m potentia l acidit y fro m sulfu r correspond s wit h actua l potentia l acidit y fro m sulfur

. I f part o f th e sulfu r occur s i n othe r insolubl e forms

, i.e. , sulfate

, the maximu m a s calculate d wil l overestimat e acid-formin g MORRISO N KNUDSE N CORPORATIO N BB\1S83\ZINCRFT\FinaJ- «

3- 6 [Re v 001/13/93 ]

### potential

. I n orde r t o determine th e tru e aci d formin g potential
, a secon d metho d for determinin g th e sulfu r conten t o f th e sample s wa s utilized

. Thi s wa s EP A Metho d 3.2. 6 (EPA

, 1978)

. Thi s metho d determine s th e hydrochlori c aci d extractable
, nitri c aci d 

### extractable
, an d non-extractabl e form s o f sulfur

, whic h ar e no t considere d t o b e aci d formers

. 3.3.1. 4 Neutralizatio n

Potentia l 

### Neutralizatio n potentia l wa s determine d b y Metho d 3.2. 3 (EPA

, 1978)

. Th e amoun t o f 

### neutralizin g base
, includin g carbonates
, present i n overburde n material s i s determine d b y treatin g a sampl e wit h a know n exces s o f standardize d hydrochlori c acid

. Th e sampl e and th e aci d ar e heate d t o ensur e tha t th e reactio n betwee n th e aci d an d th e neutralize s goe s t o completion

. A calcium carbonat e equivalen t o f th e sampl e i s obtaine d b y determinin g th e amoun t o f unconsume d aci d b y titratio n wit h standardize d sodium hydroxide

. 3.3.1. 5 Catio n Exchang e Propertie s 

### Catio n Exchange Capacit y (CEC ) i s a measur e o f how readil y a materia l wil l sor b cation s 

### ont o it s surfac e o r int o it s matrix

. Th e CE C wa s measure d usin g EP A metho d 908 0 (EPA

, 1986)

, i n whic h result s ar e expresse d i n milliequivalent s (meq ) pe r 10 0 gram s o f material

. 3.3. 2 Leachabilit y Testin g 

### Eac h o f th e collecte d zin c sla g sample s wa s subjecte d t o leachin g test s followin g EP A 

### Metho d 1312 , the Syntheti c Precipitatio n Leachin g Procedur e (SPLP)

. One sampl e wa s als o subjecte d t o colum n leac h testing

. Bot h test s ar e describe d below

. Metho d 131 2 - Syntheti c Precipitatio n Leachin g Procedur e (SPLF ) 

### SPL P analyse s wer e performe d accordin g t o standar d methodology
, wit h tw o mino r 

### modifications

. Th e metho d state s tha t th e sampl e passin g a 9.5m m siev e (particle s smalle r tha n abou t 3/ 8 inch ) wil l b e utilized

. Fo r th e zin c sla g samples
, neither siz e reductio n no r screenin g wa s employed

. Secondly

, th e metho d state s tha t th e minimu m sampl e siz e i s 10 0 

### grams

. Th e sampl e siz e use d fo r th e sla g wa s 100 0 grams

. A correspondin g increas e i n th e extractio n flui d maintaine d th e specifie d extractio n flui d t o sampl e rati o o f 20:1

. Thes e 

### method modification s wer e initiate d t o ensur e tha t fiel d condition s wer e represente d a s closel y a s possible

. 

### A s specifie d b y th e metho d (fo r soil s wes t o f th e Mississipp i River)

, th e extractio n flui d wa s 

### p H 5. 0 ±0. 2 unit s usin g a 60:4 0 rati o o f sulfuri c an d nitri c acid

. Thi s p H correspond s t o that
MORRtSO N KNUDSE N CORPORATIO N BB\1883\2INCRPT\Fln«l- W

3' 7 (R«v O 01/13/93 ]

### estimate d

fo r th e area
. A s n o dat a specifi c t o Leadvill e exists , M K compile d dat a fo r rainfal l fro m numerou s weathe r station s i n mountainou s region s o f Colorado

. Base d o n thi s 

### state-wid e data
, th e averag e p H o f th e rainfal l i n th e Leadvill e are a i s assume d t o b e approximatel y 5. 0 (Tabl e 3-3)

. 

### Th e extractio n flui d an d sample s ar e mechanicall y shaken fo r a 24-hou r period

. Th e eluat e 

### i s the n filtere d throug h a 0. 6 -O.Sum glas s fibe r filte r an d analyzed fo r metal s an d anions o f interest

. 

### Column Leachin g Test s The colum n leac h tes t wa s ru n usin g a downflo w unsaturate d configuration

. A colum n 

### diamete r o f eigh t inche s wa s selecte d t o b e severa l time s th e nomina l diamete r o f th e zin c 

### sla g particle s t o be tested

. Th e testin g laborator y prepared
, packed
, an d consolidate d th e materia l int o th e three-foot-lon g column

. Th e unsaturate d downflo w colum n require d periodi c presentatio n o f th e lixivian t followe d b y an equa l perio d o f drainin g and aeration

. Eac h introductio n o f flui d wa s designe d t o simulat e a one-inc h rainfal l even t fo r th e eight

inc h diamete r column
, an d eac h even t wa s equa l t o approximatel y 0. 8 liter s o f lixiviant

. On e hundre d cycles or "rainfal l events " wer e conducte d wit h collectio n o f th e eluat e a t th e conclusio n o f eac h event

. Initially

, th e eluat e fro m event s 5 , 25 , 50 , 7 5 an d 10 0 wer e analyze d fo r anion s an d TA L 

### metal s (plu s silico n minu s mercury)

. Afte r evaluatio n o f th e result s fro m thes e events , additiona l even t eluate s wer e analyze d t o fil l dat a gap s (Sectio n 4.5)

. Physica l Testin g Sieve

, hydrometer
, an d Microtra c analyses wer e performe d t o determin e th e particle-siz e distributio n o f zin c slag

. Siev e Analysi s Siev e analysi s wa s conducte d followin g AST M D 422-6 3 (ASTM

, 1992a)

. Thi s method 

### provide s fo r quantitativ e determinatio n o f particl e siz e distributio n i n soi l matrices

. Th e distributio n o f particl e size s greate r tha n 7 5 micron s (retaine d o n a numbe r 20 0 sieve ) i s determine d b y mechanicall y shakin g the materia l throug h a serie s o f successivel y smalle r 

### sieves

. Th e materia l retaine d o n eac h siev e i s weighe d t o determin e th e percen t o f eac h particl e size

. Fo r thi s analysis
, Standar d Tyle r siev e size s wer e used

.

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\FinaJ-R I

J- Q (Re v 001/13/93 ]

### Tabl e 3- 3

p H

(Standar d Units ) Statfo B Nam e Count

y Elevatio n (meters ) 198 4 198 5 198 6 198 7 198 8 198 9 199 0 Sugarloa f Boulde

r 252

4 4.9 7 5.0 0 5.1 8 4.8 7 Niwo t Saddl e Boulde

r 352

0 Fou r Mil e Par k Garfiel

d 250

2 5.0 5 5.5 0 5.2 9 Sunligh t Pea k Garfiel

d 320

6 Rock y Mt n Nat' 1 Par k

- Beave r Meadow s Larime

r 249

0 5.1 4 4.9 9 5.0 7 5.1

9 52 6 52 4 -Loc h Val e Larime

r 315

9 Dr y Lak e Rout

t 252 7 4.7 8 Buffal o Pass Routt 323 4 Enginee r Mt n Guar d Statio n Sa n

Jua n 275

8 4.9 2 5.0 8 MolasPas s S a n

Jua n 328

6 Manito u Telle r 236 2 4.9 0 4.8 6 4.8 2 4.8

5 5.0 9 4.9 4 Th e geometri c averag e o f thes e value s i s 5.04

. Blank s indicat e n o dat a wa s collected

.

- indicate s th e dat a di d no t mee t th e NADP completeness criteria

. Th e station s i n th e sam e count y ar e paired mountain/valle y meteorologica l stations

.Hydromete r

Analysi s Hydromete r analyse s wer e conducte d o n material s passin g th e numbe r 1 0 Tyle r sieve , i.e. , materia l size s les s tha n 1.7mm , followin g AST M Metho d D422-6 3 (ASTM

, 1992a)

. Thi s techniqu e involve s placin g th e material i n solutio n containin g a dispersin g agen t an d 

### measurin g the densit y o f the solutio n a s the materia l settles

. Siz e fraction s ar e determine d fro m th e time require d fo r th e materia l t o settl e ou t o f solution

. Th e specifi c gravit y o f th e minu s 1 0 mes h sla g wa s determine d fo r us e i n particl e siz e calculations

. Microtra c Analysi s 

### The Microtra c metho d wa s use d t o evaluat e onl y the smalle r particl e siz e fraction s i n the 

### sampl e portio n that passe d th e 4 8 mes h sieve

. Th e Microtra c metho d use s th e genera l theorie s o f lo w angle
, forwar d ligh t scattering , combined wit h microprocesso r technology

. A "cloud " o f particle s i s passe d throug h a helium-neo n lase r bea m causin g ligh t t o b e scattere d a t angles relate d t o particl e size

. Specially-designe d

optica l equipment unscramble s th e ligh t informatio n int o distinc t channe l size s ove r th e rang e o f 0.1 2 t o 70 0 microns

. Thi s techniqu e provide s a continuu m o f particl e siz e measurement s ove r the rang e
o f interest

. Th e dat a i s reporte d a s a percentag e o f material
, b y volume
, withi n a certai n siz e range
. 3. 4 Ai r Qualit y Investigatio n Ai r pathwa y analysi s wa s use d t o determin e potentia l ambien t ai r concentration s o f metal s
and particulate s resultin g fro m the win d erosio n o f the zin c sla g pile

. The firs t ste p i n thi s 

### approac h i s t o characteriz e th e emissio n potentia l o f material fro m th e zin c sla g pile

. I n th e absenc e o f site-specifi c emissio n measurements , the emission s ar e estimated

. I t i s als o necessar y t o characteriz e th e condition s unde r whic h emission s fro m th e zin c sla g pil e occur
. Onc e th e emissio n informatio n i s obtained
, th e dispersio n o f thi s materia l downwin d an d resultin g concentration s are determine d a s a functio n o f atmospheri c characteristics
, i.e., 

### win d speed
, win d direction
, an d atmospheric stability

. Th e dispersio n mode l i s th e too l tha t perform s th e calculation s necessar y t o determin e th e downwin d concentration s fro m th e emissio n rate s and meteorologica l conditions

.

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3- 9 [Re v 001/13/93]3.4. 1

Meteorologica l Dat a 

### M K coordinate d wit h ASARC O t o obtai n meteorologica l dat a collecte d unde r thei r Administrativ e Order o n Consen t fo r th e Ya k Tunnel

. ASARCO' s technical consultan t ha d 

### establishe d tw o meteorologica l station s withi n th e Californi a Gulch site : on e nea r th e Ya k Tunne l an d on e nea r th e Colorad o Mountai n College

. A year' s wort h o f dat a ha d bee n collecte d at eac h o f thes e stations

. The Leadvill e airpor t als o ha s a meteorologica l statio n withi n the sit e that ha s bee n establishe d fo r severa l years

. 

### Dat a fro m th e Colorad o Mountai n Colleg e (CMC ) statio n (Res-ASARCO

, 1991 ) wa s selecte d a s th e mos t representativ e dat a se t availabl e fo r assessin g ai r qualit y impact s fro m th e zin c sla g pile

. Th e Ya k Tunne l statio n dat a i s likel y affecte d b y loca l topography tha t result s i n win d flo w pattern s no t representativ e o f th e zin c sla g pil e location

. Th e airpor t observation s ar e limite d t o period s whe n personne l ar e working
, typicall y not throug h the night
, an d ar e therefor e no t appropriat e t o reliabl y serv e a s inpu t t o ai r emission s calculation s o r a n qualit y dispersio n model

. Th e dat a fro m th e CM C statio n consist s o f hourl y average s o f temperature , win d speed
, win d direction
, an d sigma thet a (th e standar d deviatio n o f th e horizonta l win d directio n use d

a s a n indicatio n o f atmospheri c stability ) measure d a t 1 0 meter s abov e groun d level

. Missin g dat a value s wer e note d b y M K bu t no t filled

. Sixty-fiv e day s wer e reporte d fo r whic h som e or al l hour s had missin g data

. Mos t o f thes e day s occurre d i n May

, September

, 

### October

, and Novembe r resultin g i n a n 8 2 percen t dat a collectio n efficiency

. Instea d o f fillin g i n inappropriat e data
, M K delete d eac h da y wit h missin g dat a fro m th e dat a set

. Th e fina l meteorologica l dat a fil e covere d th e perio d fro m Octobe r 199 0 t o Septembe r 1991

. 3.42 Emissio n Rat e Estimate s Potentia l fugitiv e dus t emission s fro m th e zin c sla g pil e wer e estimate d usin g th e procedur e outline d i n AP-42

, sectio n 11.2. 7 (EPA

, 1988a)

, a s recommende d b y th e EP A (EPA

, 1992)

. Th e firs t ste p i n thi s procedur e i s t o determin e th e threshol d frictio n velocit y (i.e.

, th e win d spee d abov e whic h surfac e materia l become s airborne ) fro m th e mod e o f th e particl e siz e distribution

. Th e procedur e t o determin e particl e siz e b y siev e analysi s i s describe d i n AP

42

. Variation s fro m thi s procedur e include d usin g a sampl e o f materia l collecte d fro m th e 

### surfac e t o a dept h o f thre e fee t instea d o f collectin g jus t th e surfac e laye r o f loos e particles
, and sievin g wit h severa l mor e size s o f sieve s tha n the fiv e mentione d i n the method

. Usin g th e zero-to-three-foo t sampl e dat a i s considere d representativ e o f th e surfac e materia l

MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Final-R I

3 " 1 0 [Re v 001/13/93]

### becaus

e th e pil e i s relativel y homogeneou s wit h respec t t o depth

. Th e dat a fro m th e siev e analysi s wa s re-groupe d s o that th e siev e categories woul d matc h thos e specifie d i n th e method

. 

### The result s o f the siz e distributio n ar e presente d i n Tabl e 4-1

. O f the fou r sample s collected
, onl y on e sample
, HSS102

, ha d a bimoda l distribution
, wit h a hig h percentag e o f 

### larg e materia l an d fines

. Mos t o f th e material fo r th e othe r thre e sample s di d no t pas s throug h th e Tyle r numbe r 5 siev e an d th e dat a wa s no t bimodal

. Th e win d spee d tha t i s necessar y t o erod e th e Wester n Zin c sla g pil e material an d suspen d 

### i t i n th e atmospher e i s determine d b y relatin g th e mod e o f th e siz e distributio n t o th e threshol d frictio n velocit y (tha t win d velocit y a t whic h particle s begi n t o becom e entraine d int o th e ambien t air)

. The informatio n i n Tabl e 11.2.7. 1 i n AP-4 2 relate s modes o f particl e siz e distribution s t o threshol d frictio n velocities

. Th e dat a i n th e table
, reproduce d i n Appendi x F

, wa s determine d empiricall y throug h researc h effort s b y th e EPA

. Th e tabl e indicate s tha t th e threshol d frictio n velocit y fo r particle s th e siz e o f th e zin c sla g i s greate r than 10 0 centimeter s pe r secon d (cm/sec)

. Th e nex t ste p i s t o determin e i f th e win d speed s i n th e are a are grea t enoug h t o entrai n surfac e material int o th e ambien t air

. Thi s i s don e b y comparin g th e threshol d frictio n velocit y wit h th e win d speed

. However

, usin g hourly-average d win d spee d dat a fo r th e compariso n i s no t appropriat e becaus e mos t erosio n event s typicall y las t betwee n on e an d fou r minute s (EPA

, 1988a)

. I t i s th e sustaine d win d gust s embedde d i n th e hourly-average d win d speed s tha t ar e mor e relevant

. Th e "fastes t mile " paramete r i s th e mos t routinel y measure d meteorologica l variabl e tha t bes t reflect s th e magnitud e o f sustaine d win d gusts

. Th e fastes t mil e i s define d a s th e valu e that represent s the win d spee d correspondin g t o the whol e mil e o f win d movemen t tha t ha s 

### passe d b y the one mil e contact anemomete r i n the leas t amoun t o f time

. Typically

, fastes t mil e dat a i s availabl e fro m Loca l Climatologica l Dat a (LCD ) summaries

. Sinc e i t i s no t collecte d at the Leadvill e airport , a literatur e searc h wa s conducte d t o fin d a suitabl e empirica l relationshi p fo r derivin g fastes t mil e dat a fro m hourl y average d on-sit e win d spee d data

. A suitabl e equatio n i s containe d i n E

. Simi u an d R

. H

. Scanlan' s boo k Wind Effects

o n Structures: A n Introduction t o Wind Engineering, (Simi u an d Scanlan

, 1978) :

MORRISO N KNUDSE N CORPORATION BB\1893\ZINCRPT\Final-R I

3-1 1 [Re v 001/13/93 ]U

t (z ) = U
3600 (z)[ l + (0.9 8 c(t))/ln(z/z
0 ) ] wher e z = heigh t a t whic h win d spee d i s t o b e determine d

z 0 = roughnes s heigh t c(t ) = constan t = 1.0 2 fo r a n averagin g perio d o f 10 0 second s Uaeo o = hourl y averaged win d spee d U
t (z ) = averaged win d spee d a t time "t " (Th e sectio n presentin g thi s conversio n ha s bee n duplicate d an d provide d i n Appendi x F. ) Sinc e a typica l erosio n even t last s one t o fou r minute s (EPA

, 1988a ) and i s capabl e o f completel y depletin g th e erosio n potentia l fo r a give n sourc e area , a win d spee d averagin g time o f 10 0 second s wa s selecte d a s a valu e tha t woul d yiel d a win d spee d simila r t o th e fastes t mil e speed s i n LC D summaries

. Applicatio n o f thi s equatio n result s i n a "100-second " win d spee d abou t 1.1 3 time s highe r tha n th e "360 0 second " win d speed

. Thus

, i t i s appropriat e t o multipl y th e maximu m observe d hourl y win d spee d b y 1.1 3 t o obtai n th e 

### fastes t mile

. Fo r example
, the maximu m observed hourl y averag e win d spee d wa s 9.1 2 m/sec

, o r 20. 4 miles pe r hou r (mph)

. Multiplyin g thi s value b y 1.1 3 equal s a 10. 3 m/se c (23.0 5 mph ) fastes t mile

. 

### Th e 100-secon d perio d wa s selecte d t o represen t th e duratio n o f th e typica l erosio n even t fo r tw o reasons

. First

, i t wa s withi n th e range o f erosio n events , whic h th e EP A specifie s i n AP-42

, Sectio n 11.2.7 , Industrial Wind Erosion (EPA

, 1988a)

, a s lastin g betwee n on e an d fou r minute s (6 0 t o 24 0 seconds)

. Second

, i n orde r t o determin e the win d spee d tha t correspond s t o th e fastes t mile
, Equatio n 2.3.3 0 o f Simi u an d Scanla n (1978 ) need s t o b e solved

. I n orde r t o solv e thi s equation , th e value o f th e coefficien t c(t ) need s t o b e quantified

. Tabl e 2.3. 2 i n th e reference d tex t boo k list s severa l coefficient s fo r selec t tim e period s ( a cop y o f thi s tabl e ha s bee n include d i n the Simi u an d Scanla n attachmen t t o thi s Appendi x F)

. Onl y tw o coefficient s ar e give n fo r tim e period s tha t ar e withi n th e 60

- t o 

### 240-secon d range : 10 0 an d 20 0 seconds

. O f thes e tw o values
, th e 100-secon d coefficien t

wa s chosen

. Th e 100-secon d value i s conservativ e becaus e i t result s i n a greate r fastes t mil e valu e tha n th e 200-secon d coefficient ; therefore

, increasin g th e calculate d emissio n rate

.

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Final-R l

3-1 2 [Re v 001/13/93 )Tw o

articles hav e bee n reviewe d wit h th e inten t o f providin g supportin g evidenc e t o verif y applicabilit y o f the relationshi p betwee n the hourl y averaged win d spee d an d the win d spee d whic h correspond s t o the fastes t mile

. The two article s reviewe d ar e a s follows : Glidden

, D.E

. "Winte r Win d Studie s i n Rock y Mountai n Nationa l Park. " Rock y Mountai n Natur e Association

, Este s Park

, Colorado

, 1982

. Judson

, A

. "Th e Weathe r an d Climat e o f a Hig h Mountai n Pas s i n th e Colorad o Rockies. " Rock y Mountai n Fores t an d Rang e Experimen t Station

. For t Collins

, Colorado

, 1965

. Althoug h th e article s di d no t contai n informatio n o n th e win d spee d correspondin g t o th e fastes t mile
, th e article s di d contai n win d dat a summarize d ove r severa l tim e period s differen t fro m thos e recorde d i n Leadville

, suc h a s th e fastes t gust , 5-minut e summaries, hourl y summaries, an d dail y summaries

. Thes e summarie s include d maximums , minimums , an d average s fo r th e tim e period

. T o compar e the dat a presente d i n the article s t o the metho d whic h i s use d t o calculat e win d blown emission s fo r th e zin c sla g pile
, th e equatio n wa s modifie d slightl y t o compar e th e rati o o f th e fastes t 1-secon d win d spee d (gust ) t o th e hourl y win d speed

. Thi s correspond s t o usin g c(t)

= 3.0 0 i n th e Simi u an d Scanla n equatio n (1978)

. Th e followin g tabl e summarize s th e result s o f th e rati o o f th e fastes t gust t o th e 1-hou r win d spee d (1-hour gus t ratio ) fo r fou r location s mentione d i n th e abov e reference d articles

. Th e Mines Pea k statio n wa s locate d nea r Berthoud Pas s a t a n elevatio n o f 380 8 meters

. Th e othe r thre e station s wer e locate d withi n th e boundarie s o f Rock y Mountain Nationa l Park

. TR 3 and TRI O wer e locate d alon g Trai l Ridg e Roa d a t an elevatio n o f 11,60 1 fee t and 11,81 7 feet

, respectively

. Th e Longs Pea k statio n wa s locate d at th e summi t o f Long s Pea k

an d a n elevatio n o f 14,25 5 feet

.

MORRISO N KNUOSE N CORPORATION BB\1893\ZINCRPT\Flnal-R I 3"1

3 [Re v 001/13/93 ]Observe d an d Calculate d 1-Hou r Win d Speeds : Maximu m Gus t Ratio s fo r Fou r Mountain Location s SIT E 

### Mines Pea k TR 3 

### Long s Pea k TRI O A V

G MI N N / A 1.2 7 1.3 0 1.2 1 AVERAG

E 2. 0 1.6 1 2. 0 1.5 8 A V G MA X N / A 2.5 3 3.2 0 2.2 0 CALCULATE D 1.3 6 1.4 2 1.4 2 1.3 7 The value s presente d represen t the rati o o f the maximu m gust observed eac h hou r t o the 1-hou r average d win d speed

. Fo r example
, fo r locatio n TR3

, the maximu m gus t wa s 1.6 1 time s greate r tha n th e averag e 1-hou r win d speed

. Th e colum n labelle d AV G MI N represent s th e minimu m o f al l ratio s o f th e fastes t gust represent s th e maximu m o f al l ratios

. Th e abov e value s wer e calculate d usin g parameter s correspondin g bes t t o eac h individua l site

. Th e anemometer heigh t fo r eac h statio n wa s obtaine d fro m th e references

. A surfac e roughnes s heigh t o f 0.3 5 c m wa s assume d fo r eac h site , whic h correspond s t o tha t o f snow

. 

### Th e methodolog y use d t o calculat e th e 1-hou r gust rati o appear s t o b e withi n th e rang e observed a t severa l mountai n locations

. I t wa s no t possibl e t o compar e th e calculate d an d observed value s fo r othe r time averagin g period s du e t o th e lac k o f dat a presente d i n th e articles

. Th e fastes t mil e o f 10.3 m/se c need s t o b e adjuste d fro m th e heigh t o f measuremen t (1 0 

### meters ) dow n t o th e heigh t o f th e pil e surface ; th e adjuste d win d spee d at th e surfac e i s referre d t o a s th e frictio n velocit y (u')

. Thi s i s don e usin g th e logarithmi c win d profil e relationshi p a s specifie d i n AP-42

, sectio n 11.2.7 , Equatio n 4 :

u * = 0.05 3 U 1 0 T h e frictio n velocit y i s the n compare d t o th e threshol d frictio n velocit y calculate d fo r th e zin c sla g t o determin e i f th e frictio n velocit y i s greater , indicatin g potentia l fo r win d erosion

. 

### Result s fro m thi s ste p (presente d i n Sectio n 4.4.2 ) eliminate d th e nee d t o procee d wit h dispersio n modeling

.

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Final-R I

3-1 4 [Re v 001/13/93 ]3. 5

Relationshi p Wit h Othe r Investigatio n Program s Thi s Zin c Sla g Pil e R I require d coordinatio n wit h othe r Californi a Gulch Remedia l Investigatio n program s implemente d b y others

. Th e informatio n shared t o dat e betwee n th e variou s program s a s i t relate s t o th e Sla g Pil e RI i s discusse d below

. Mineralog y an d meta l speciatio n studie s are bein g performe d b y Resurrectio n an d ASARC O unde r th e Final Work Plan

- Metals Speciation an d Source Characterization a t California 

### Gulch CERCLA Site (Resurrection

, 1992)

. Analytica l dat a wil l b e develope d that characteriz e th e distribution
, geochemistry
, an d morpholog y o f differen t meta l compound s
a t th e site

. Thes e factor s ma y b e critica l variables i n th e determinatio n o f th e bioavailabilit y
o f lea d an d assessin g th e potentia l huma n healt h risk

. Th e zin c sla g sample s wer e prepare d (pulverize d t o minu s 250 microns ) and delivere d t o th e Cam p Dresse r & McKe e fiel d laborator y i n Leadville

. I t i s understoo d that thes e sample s wil l undergo variou s tests , includin g XRF

, XRD

, microprobe
, optica l microscopy , an d lea d isotop e analysis

. I t i s anticipate d tha t thes e result s wil l b e use d t o determin e metal s ratios o f th e Wester n Zin c slag
, origi n o f th e or e tha t wa s smelte d t o for m th e slag
, an d relativ e bioavailabilit y o f sla g particle s base d o n th e specie s o f metal s i n th e slag

. 3.5. 1 ASARC O Meteorologi c Monitorin g Progra m A s state d previously
, meteorologi c dat a (Res-ASARCO

, 1991 ) develope d b y Res-ASARC O unde r th e California Gulch Ai r Monitoring Work Plan (EPA

, 1990b ) ha s bee n provide d t o M K an d wa s use d fo r inpu t t o th e Wester n Zin c sla g pil e ai r dispersio n modeling

.

MORRISO N KNUDSEN CORPORATIO N BB\1893\ZINCRPT\Flnal-F H 3-1

5 tRe v 001/13/93 ]4 . 0

CHARACTERISTIC

S O F TH E ZIN C SLA G PIL E The result s o f historica l researc h relatin g t o th e developmen t o f th e zin c smelte r an d sla g pile
, fiel d reconnaissanc e o f th e smelte r an d sla g pile
, an d th e physica l an d stabilit y characteristic s o f th e sla g pil e are reporte d i n thi s section

. A summar y i s als o provide d o f th e result s o f compositiona l an d teachabilit y analyse s alon g wit h qualit y assuranc e sampl e dat a an d dat a validatio n procedures

. 4. 1 Smelte r Histor y an d Sla g Pil e Developmen t Summar y Th e inten t o f thi s summar y i s t o giv e a n overvie w o f Leadvill e are a smelte r history
, a s i t relate s t o th e Wester n Zin c sla g pil e development

. 4.1. 1 Brie f Histoi y o f Leadvill e Smeltin g Althoug h place r gol d wa s foun d i n Californi a Gulc h i n 1859 , lead-silve r minin g di d no t begi n unti l th e summe r o f 1874

. B y 1875 , th e Malt a Smelte r wa s buil t t o proces s th e silve r ore
. Th e followin g 2 7 year s wer e Leadville' s mos t productiv e an d activ e perio d fo r minin g an d smelting

. B y 1879 , al l o f th e majo r lea d smelte r area s i n th e Leadvill e Minin g Distric t wer e operating ; however
, b y Augus t 1880 , hal f o f the m wer e close d largel y du e t o the cok e famin e
o f the previou s winte r (Blair

, 1980)

. The smelter s ofte n change d ownership
, capacit y and processes

. Several burne d t o the ground

. B y 1892 , th e smelter s wer e resmeltin g olde r sla g deposit s fo r recover y o f residua l metals

. I n 1893 , ther e wa s a silve r pani c durin g whic h al l o f the smelter s close d wit h onl y
a few o f the m reopening

. Zin c smeltin g bega n i n th e earl y 1900 s i n Leadvill e an d continue d fo r onl y abou t 1 2 years

. Lea d smeltin g continue d i n Leadvill e unti l 1961

. 4.1. 2 Wester n Zin c Smelte r an d Sla g Pil e Histor y Th e Wester n Zin c Minin g an d Reducin g Compan y buil t a zin c smelte r wes t o f Leadvill e i n 1914

. Th e compan y change d it s nam e t o th e Wester n Zin c Oxid e Compan y i n 191 5 an d t o Wester n Zin c Concentratin g Compan y i n 1918

. Thi s smelte r use d a Witherel l furnace

, whic h oxidize d ore s t o produc e zin c oxide

. I t ha s bee n reporte d tha t som e o f the sla g produce d at thi s zin c smelte r wa s sen t t o othe r smelters
, includin g the Arkansa s Valle y Smelter

, i n orde r that lead
, silver
, gol d an d coppe r coul d b e recovered

. Th e zin c smelte r close d i n 192 6 afte r generatin g a n estimate d 51,00 0 t o 70,00 0 ton s o f sla g (EPA

, 1991)

. Th e Wester n Zin c sla g pil e i s currentl y owne d b y Lak e County

.

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\FinaI-R !

4- 1 [Re v 001/13/83 ]4 2 Fiel d Reconnaissanc e o f th e Zin c Sla g Pil e an d Smelte r Are a 

### Th e fiel d investigatio n phas e o f th e Zin c Sla g Pil e R I include d a reconnaissanc e o f th e histori c zin c smelte r locatio n an d sla g pile

. Reconnaissanc e activitie s include d describin g th e ol d zin c smelte r location
, th e sla g pil e an d propert y i n th e vicinit y o f th e sla g pil e fo r
an y othe r smeltin g debri s or by-products
, an d othe r majo r physiographi c or cultura l features

. 

### Figur e 3- 1 present s observation s fro m th e fiel d reconnaissance

. Th e cross-hatche d lines o n th e figur e represen t area s o f smelte r foundation s an d rubble

. 

### 42.1 Th e Wester n Zin c Smelte r Th e Wester n Zin c Smelte r sla g are a cover s severa l acre s nea r th e Lak e Count y Fai r Ground s wes t o f Lak e Count y Hig h School

. Th e smelte r foundatio n i s locate d jus t eas t o f th e slag

. Thi s zin c sla g i s substantiall y differen t fro m th e dens e lea d sla g o f th e Leadvill e
area , a s i t wa s forme d b y a differen t process , recoverin g a differen t metal

. Th e color s ofte n rang e fro m red t o brow n an d th e materia l i s mor e vesicula r tha n lea d slag

. Particl e size s 

### rang e fro m soil-size d material u p t o piece s severa l inche s i n diameter

. Muc h o f th e sla g pil e appear s t o hav e bee n worked
, although ther e i s one larg e are a consistin g o f mostl y welde d material

. Som e o f th e soil s i n th e are a o f th e pil e appea r t o b e disturbe d (excavated)

. Th e thinne r zin c sla g area s an d soil s suppor t trees , bushe s an d grasses

. Railroa d track s ru n nearby
, a s d o severa l roads

. N o stream s o r ponde d water wer e observe d i n th e area
. Also

, n o evidenc e o f fine s wer e observe d t o hav e washe d fro m th e pil e b y precipitatio n runoff

. A numbe r o f bag-shape d mound s o f gre y cementiciou s materia l wer e locate d nea r th e foundatio n ruins

. Base d o n th e smeltin g metho d use d a t thi s sit e an d th e coarsel y wove n fabri c stil l adherin g t o severa l o f th e mounds
, thi s materia l appear s t o b e solidifie d zin c oxid e baghous e dust

. Ther e ar e tw o location s i n Leadvill e wher e zin c sla g wa s observed o n dir t roadways : o n th e
roa d of f o f McWeth y Driv e that lead s toward s th e L a Plat a sla g pil e an d o n a sectio n o f th e
roa d tha t passe s t o th e nort h o f th e Hecl a tailing s ponds

. Othe r potentia l use s o f thi s materia l tha t coul d accoun t fo r volume los s hav e not bee n documented

. 4. 3 Physica l Characteristic s 

### Particl e siz e an d pil e volume s ar e th e majo r physica l characteristic s o f th e Wester n Zin c sla g pil e that wer e determine d durin g th e RI

.

MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Final- «

4- 2 [Re v 0 01/13/93 )TABU* 4- 1 PARTICL E SIZ E TESTIN G RESULT S ZIN C SLA G PIL E (HSS101 ) SEIV E ANALYSI S SEIV E NO

.
6 4 " 3 " 2 1 " 1/2 " 3 M 4 6 8 1 0 1 4 2 0 2 8 3 5 4 8 6 5 SEIV

E OPENING

, m m

152. 4 101. 6 76. 2 50. 8 26. 5 13. 2 6.7 0 4.7 5 3.3 5

. 2.3 6 1.7 0 1.1 8 0.85 0 0.60 0 0.42 5 0.30 0 0.21 2 % PASSIN G

100. 0 100. 0 100. 0 94. 8 83. 4 69. 4 53. 4 49. 1 41. 9 35. 5 30. 4 25. 4 21. 6 17. 8 14. 6 12. 3 10. 3 HYDROMETE R ANALYSI S SEIV E NO

. 1 0 3 5 4 8 6 5 10 0 15 0 20 0

HYDROMETE R RESULT S SEIV

E OPENING

, p m 170 0 42 5 30 0 21 2 15 0 10 6 7 5 EQUIVALEN T DIAMETE R (fun ) 2 9 1 9 1 1 8 6 3 1 % PASSIN G

30.4 16. 4 13. 9 12. 2 10. 6 9. 2 7. 8 % FINE R

4. 2 3. 4 2. 5 2. 3 1. 9 1. 5 1. 3 SPECIFI C GRAVIT Y 3.

3 MICROTRA

C ANALYSI S EQUIVALEN T DIAMETER (pm )
704. 0 592. 0 497. 8 418. 6 352. 0 296. 0 248. 9 209. 3 176. 0 148. 0 124. 5 104. 7 88. 0 74. 0 62. 2 52. 3 44. 0 37. 0 31. 1 26. 2 22. 0 18. 5 15. 6 13. 1 11. 0 9.2 5 7.7 8 6.5 4 5.5 0 4.6 2 3.8 9 3.2 7 2.7 5 2.3 1 1.9 4 1.6 4 1.3 8 1.1 6 0.9 7 0.8 2 0.6 9 % FINE R

12.3 0 12.0 9 11.8 2 11.4 7 11.0 4 10.5 1 9.8 9 9.2 0 8.4 7 7.7 5 7.0 6 6.4 0 5.7 7 5.1 5 4.5 5 3.9 9 3.4 9 3.0 4 2.6 5 2.3 1 2.0 3 1.7 9 1.5 8 1.3 9 1.2 3 1.0 9 0.9 7 0.8 7 0.7 7 0.6 8 0.6 0 0.5 2 0.4 4 0.3 7 0.3 1 0.2 4 0.1 8 0.1 2 0.0 7 0.0 3 0.0 0

BB\123\zinctblsUbt4- 1

6/29/9 2TABL E 4-1 , coot' d PARTICL E SIZ E TESTIN G RESULT S ZIN C SLA G PILE (HSS102 ) SEIV E ANALYSI S SEIV E NO

.

6 " 4 " 3 " 2 1 " 172 3 M 4 6 8 1 0 1 4 2 0 2 8 3 5 4 8 6 5 SEIV

E OPENING

, m m

152. 4 101. 6 76. 2 50. 8 26. 5 13. 2 6.7 0 4.7 5 3.3 5

. 2.3 6 1.7 0 1.1 8 0.85 0 0.60 0 0.42 5 0.30 0 0.21 2 % PASSIN G

100. 0 100. 0 100. 0 97.3 89. 2 77. 3 63. 8 61. 2 56. 3 52. 3 49. 4 46. 6 44. 7 42. 9 41. 4 40. 4 39. 5 HYDROMETE R ANALYSI S SEIV E NO

. 1 0 3 5 4 8 6 5 10 0 15 0 20 0

HYDROMETE R RESULT S SEIV

E OPENING

, p m 170 0 42 5 30 0 21 2 15 0 10 6 7 5 EQUIVALEN T DIAMETE R (jan) 3 0 1 9 1 1 8 6 3 1 % PASSIN G

49. 4 19. 9 15. 6 12. 5 10. 2 8. 2 6. 6 % FINE R
6. 2 5. 1 3. 4 2. 7 2. 4 1. 7 1. 7 [SPECIFI C GRAVIT Y 3.

3 MICROTRA

C ANALYSI S EQUIVALEN T DIAMETE R (pm )
704. 0 592. 0 497. 8 418. 6 352. 0 296. 0 248. 9 209. 3 176. 0 148. 0 124. 5 104. 7 88. 0 74. 0 62.2 52. 3 44. 0 37. 0 31. 1 26.2 22. 0 18. 5 15. 6 13. 1 11. 0 9.2 5 7.7 8 6.5 4 5.5 0 4.6 2 3.8 9 3.2 7 2.7 5 2.3 1 1.9 4 1.6 4 % FINE R

40.4 0 39.8 5 39.1 4 38.1 9 36.9 3 35.3 5 33.3 9 31.10 28.6 0 25.9 9 23.3 5 20.7 2 18.0 9 15.5 0 13.0 4 10.8 0 8.8 3 7.1 7 5.8 0 4.7 1 3.8 5 3.1 7 2.6 3 2.2 0 1.8 4 1.5 4 1.2 8 1.0 6 0.8 6 0.6 8 0.5 1 0.3 6 0.2 2 0.1 3 0.0 4 0.0 0

BBV123tfnctblsttbl4-1 a

6/29/9 2TABL E 4-1 , coot' d PARTICL E SIZ E TESTIN G RESULT S ZIN C SLA G PILE (HSS1Q3 ) SEIV E ANALYSI S SEIV E NO

.

6 4 3 2 " 

## r 1/2 " 3 M 4 6 8 1 0 1 4 2 0 2 8 3 5 4 8 6 5 SEIV

E OPENING

, m m

152. 4 101. 6 76. 2 50. 8 26. 5 13. 2 6.7 0 4.7 5 3.3 5 2.3 6 1.7 0 1.1 8 0.85 0 0.60 0 0.42 5 0.30 0 0.21 2 % PASSIN G

100. 0 100. 0 100. 0 93. 8 75. 5 61. 2 44. 0 41. 3 34. 3 27. 9 23. 0 18. 2 15. 2 12. 3 9. 9 8. 1 6. 7 HYDROMETE R ANALYSI S SEIV E NO

. 1 0 3 5 4 8 6 5 10 0 15 0 20 0

HYDROMETE R RESULT S SEIV

E OPENING

, p m 170 0 42 5 30 0 21 2 15 0 10 6 7 5 EQUIVALEN T DIAMETE R dim) 2 6 1 7 1 0 7 5 3 1 % PASSIN G
23. 0 13. 0 11. 5 10. 3 9. 3 8. 4 7. 5 % FINE R
5. 2 4. 4 3. 3 2. 7 2. 3 1. 6 1. 4 [SPECIFI C GRAVIT Y MICROTRA C ANALYSI S EQUIVALEN T DIAMETE R 0*m )
704. 0 592. 0 497. 8 418. 6 352. 0 296. 0 248. 9 209. 3 176. 0 148. 0 124. 5 104. 7 88. 0 74. 0 62. 2 52. 3 44. 0 37. 0 31. 1 26.2 22. 0 18. 5 15. 6 13. 1 11. 0 9.2 5 7.7 8 6.5 4 5.5 0 4.6 2 3.8 9 3.2 7 2.7 5 2.3 1 1.9 4 1.6 4 1.3 8 1.1 6 0.9 7 0.8 2 % FINE R

8.1 0 8.0 3 7.9 2 7.7 3 7.4 5 7.1 1 6.7 2 6.3 0 5.8 5 5.3 9 4.9 5 4.5 3 4.1 2 3.7 3 3.3 5 2.9 8 2.6 4 2.3 0 1.9 8 1.6 8 1.4 1 1.1 9 1.0 1 0.8 6 0.7 4 0.6 3 0.5 4 0.4 6 0.4 0 0.3 4 0.2 9 0.2 4 0.2 0 0.1 6 0.1 3 0.0 9 0.0 6 0.0 3 0.0 1 0.0 0

BB\123WnctbNW4-1 b

6/29/9 2TABL E 4-1 , cooT d PARTICL E SIZ E TESTIN O RESULT S ZIN C SLA G PILE (HSS104 ) SEIV E ANALYSI S SEIV E NO

.

6 " 4 " 3 " 2" 1 " 1/2 3 M 4 6 8 1 0 1 4 2 0 2 8 3 5 4 8 6 5 SEIV

E OPENING

, m m

152. 4 101. 6 76. 2 50. 8 26. 5 13. 2 6.7 0 4.7 5 3.3 5

. 2.3 6 1.7 0 1.1 8 0.85 0 0.60 0 0.42 5 0.30 0 0.21 2 % PASSIN G

100. 0 100. 0 97. 0 92. 2 81. 1 72. 5 60. 6 59. 4 32. 5 9. 9 8. 1 6. 3 5. 1 4. 0 3. 1 2. 4 1. 9 HYDROMETE R ANALYSI S SEIV E NO

. 1 0 3 5 4 8 6 5 10 0 15 0 20 0

HYDROMETE R RESULT S SEIV

E OPENING

, p m 170 0 42 5 30 0 21 2 15 0 10 6 7 5 EQUIVALEN T DIAMETE R Cim ) 3 2 2 1 1 2 9 6 3 1 % PASSIN G

8. 1 4. 3 3. 5 2. 9 2. 4 2. 0 1. 6 % FINE R

0. 5 0. 4 0. 4 0. 3 0. 2 0. 2 0. 1 

## [SPECIFI C GRAvrnr 3. 0 MICROTRA

C ANALYSI S EQUIVALEN T DIAMETE R (pm )
704. 0 592. 0 497. 8 418. 6 352. 0 296. 0 248. 9 209. 3 176. 0 148. 0 124. 5 104. 7 88. 0 74. 0 62. 2 52. 3 44. 0 37. 0 31. 1 26. 2 22. 0 18. 5 15. 6 13. 1 11. 0 9.2 5 7.7 8 6.5 4 5.5 0 4.6 2 3.8 9 3.2 7 2.7 5 % FINE R

2.4 0 2.3 7 2.3 3 2.2 6 2.1 7 2.0 4 1.8 8 1.7 1 1.5 3 1.3 5 1.1 8 1.0 2 0.8 7 0.7 3 0.6 1 0.5 0 0.4 1 0.3 3 0.2 6 0.2 1 0.1 7 0.1 4 0.1 1 0.0 9 0.0 8 0.0 6 0.0 5 0.0 4 0.0 3 0.0 2 0.0 1 0.0 1 0.0 0

BB\123tfnctblsttbl4-1 c

6/29/9 24.3. 1

Particl e Siz e Particl e siz e distribution s o f the zin c sla g sample s wer e determine d b y sieve , hydrometer
, an d Microtra c analyses

. Th e specifi c gravit y o f th e les s tha n No

. 1 0 mesh
, o r 1. 7 mm , 

### portio n o f the sampl e wa s als o evaluated

. 

### Th e result s o f th e particle-siz e analyse s fo r th e zin c sla g sample s ar e presente d i n Tabl e 4-1

. Th e result s indicat e 9 0 percen t or mor e o f thre e sample s whic h consiste d o f materia l betwee n scree n size s 0.21 2 m m an d 3 inches

. Onl y 6 0 percent o f th e othe r zin c sla g sampl e (HSS102 ) wa s materia l betwee n 0.21 2 m m an d 3 inches

. Thi s fine r sampl e wa s obtaine d fro m th e nort h sid e o f th e higher
, welde d are a (Figur e 3-1)

. Th e result s o f al l thre e particl e siz e determinatio n technique s - Microtrac

, siev e an d hydromete r ~ compar e well

. Th e particl e siz e dat a wa s analyze d i n orde r t o determin e th e potentiall y inspirabl e (inhalable ) an d respirabl e (capabl e o f bein g deposite d i n th e alveoli ) weigh t fractio n o f th e zin c sla g sample

. Accordin g t o Threshol d Limi t Value s give n b y th e America n Conferenc e
o f Governmenta l Industria l Hygienist s (ACGIH

, 1990)

, inspirabl e particulat e mas s i s calculate d base d on aerodynami c diameter s u p t o 10 0 ju m an d respirabl e particulat e mas s i s base d o n aerodynami c diameter s o f 3. 5 jum

. Th e EP A document
, Risk Assessment Guidance for Superfund Volume I, Human Health Evaluation Manual (Part A), Interim Final (p

. 6-43 ) (EPA

, 1989a ) consider s respirabl e particle s t o b e thos e wit h diameter s o f 1 0 /x m
o r less

. Th e industria l hygien e reference

, Th e Industrial Environment

- It s Evaluation an d Control, (NIOSH

, 1973 ) predict s th e inhalabl e particl e siz e base d o n th e know n behavio r
o f particle s i n ai r suspensio n an d th e anatomical arrangemen t o f th e connectin g tube s i n th e lung

. Th e referenc e predict s tha t particle s large r tha n 1 0 /n m woul d b e remove d fro m th e airstrea m whe n passin g throug h th e nos e an d uppe r airway s an d tha t particle s betwee n 5 ju m
an d 1 0 ji m i n diamete r woul d b e deposite d mainl y i n th e uppe r airway s o n th e mucociliar y escalator

. Onl y particle s i n th e rang e o f 1 /z m t o 2 ju m woul d penetrat e t o th e deepe r portion s o f th e lun g wher e depositio n i n th e alveol i ma y occur
. Base d on thes e references

, i t wil l b e conservativel y assume d tha t particle s les s tha n 10 0 M m i n diamete r are potentiall y inspirable
, an d thos e les s tha n 1 0 /u m ar e potentiall y respirable

. Tota l suspendabl e particulate s (TSP ) ar e thos e particle s les s tha n 3 0 Th e particl e siz e dat a wa s analyze d s o tha t th e weigh t percen t o f material equa l t o or fine r tha n 100/im

, 30/im

, an d lO/it m i n diamete r coul d b e calculated

. Fo r th e hydromete r data
, th e weigh t percen t o f materia l fine r tha n 30ju m an d fine r tha n lO^ m wa s linearl y interpolated

. Fo r th e siev e data
, th e percen t o f materia l fine r tha n lOO/x m wa s linearl y
MORRISO N KNUOSE N CORPORATION BB\1893\ZINCRPT\Final-R I

4- 3 [Re v 001/13/93 )TABL E 4- 2

% < 10 0 ja n %

< 3 0 in n %

< 1 0 io n

mea n mea

n ma x mea

n ma x Wester n Zin c D42 2 Microtrac 6.

7 8. 9 0.4 8 4. 1 03

3 Z l 0.9 9 02

5 5.

6 0.07 0 OJS9 L

7

BB\1V9\ZINCRR\W-TMH£4-1 2

RE V 0interpolated

.

Th e Microtra c dat a provide d percen t o f sampl e fine r tha n 10 0 /im

, 3 0 urn, an d 1 0 nm
. Th e minimum , average , an d maximu m value s fo r th e zin c sla g sample s ar e 

### presente d i n Tabl e 4-2

. Th e dat a sho w that approximatel y 7 percen t o f th e materia l i s les s tha n 10 0 /Ltm

, 3 percen t i s les s tha n 3 0 pm , an d onl y 1 percen t i s les s tha n Th e specifi c gravit y wa s determine d fo r th e les s tha n No

. 1 0 mesh
, o r 1. 7 mm , portio n o f

eac h o f the samples
, a s require d fo r calculation s i n the hydromete r test

. The specifi c gravit y
o f thi s fractio n o f th e zin c sla g sample s average s 3.25

. 4.3. 2 Histori c an d Curren t Zin c Sla g Pil e Surfac e Area s an d Volume s 

### Th e histori c volum e o f th e zin c sla g pil e wa s estimate d base d on it s siz e i n lat e 1956

. Thi s volum e wa s calculate d i n orde r t o estimat e th e amoun t o f sla g generate d b y th e smelter

. Th e histori c volum e wa s the n compare d t o th e curren t sla g pil e volum e calculate d fro m th e surve y performe d fo r thi s RI

. (Th e curren t topographi c surfac e o f th e zin c sla g pil e i s show n i n Figur e 4-1

. The histori c topographi c surfac e o f the pil e i s show n i n Figur e 4-2. ) 

### Th e volum e decreas e betwee n 195 6 an d 199 2 i s attribute d t o th e material bein g remove d fro m th e site

. Th e 195 6 aeria l photograph s fro m whic h th e historica l sla g pil e topograph y was digitized
, are describe d i n Sectio n 3.2.1

. Surfac e topography wa s digitize d i n two-foo t contou r 

### interval s b y IntraSearch

, Inc

. o f Englewood

, Colorado

. AutoCA D softwar e generate d th e surfac e o f th e sla g pile

. Th e topograph y aroun d th e perimete r o f th e sla g pil e wa s use d t o estimat e th e groun d surfac e befor e sla g deposition

. Elevatio n difference s betwee n th e tw o surface s wer e use d t o develo p an isopac h map, fro m whic h the sla g pil e volume wa s calculated

. Th e resul t o f thi s calculatio n show s tha t th e Wester n Zin c sla g pil e volume i n 195 6 wa s 35,10 0 cubi c yards

. 

### I n th e sprin g o f 1992 , a professiona l surve y tea m examine d th e zin c sla g pile
, accordin g t o procedure s reporte d i n Sectio n 3.2.2

. Fro m thi s surve y information

, a topographi c ma p o f th e pil e surface

, wit h five-foo t contours , wa s developed

. Th e curren t volum e o f th e zin c sla g pil e wa s determine d usin g procedure s a s describe d fo r estimatin g th e histori c volume i n th e precedin g paragraph

. Th e curren t volum e o f th e Wester n Zinc sla g pil e i s 22,60 0 cubi c 

### yards

. Th e pil e surfac e are a fro m a ma p vie w perspective , i s 201,00 0 squar e feet

.

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Flnal- «

4- 4 [Re v 001/13/93 ]

### s U



## S 

## 5 n l
L J £ L d
N 515,50 0 

## LEGEN D

- 2 SURFAC E CONTOU R INTERVA L A D D 9000 T O CONTOU R INTERV A MONITO R WEL L

• BOUNDAR Y O F VOLUM E CALCULATIO N ANGL E O F REPOS E CALCULATIO N SECTIO N SMELTE R RUBBL E ARE A

N 515,25 0

N 515,00 0

N 514,75 0

N 514,50 0 VOLUME S B Y FLATIRON S SURVEYING

, INC

. GRID METHO D AVERAG E EN D ARE A METHO D T I N SUBTRACTIO N METHO D 21,900Cu

.

Yds

. 23,13 0 Cu

. Yds

. 22,96 0 Cu

. Yds

. SURFAC E ARE A 201,29 0

Sq

. Ft

.

DATUM : 10795.0 , DATU

M = 10785.0 ,

6 c o 

# l l DATU M 10800. 0 

## 5 1 0
AVERAG E ANGL E O F REPo k = 34.1 * OUTLIN E O F HISTORI C (1956 ) PIL E SUPERIMPOSE D O N CURREN T SURFAC E F O R READE R COMPARISIO N SCAL E FEE T

<CPD : 9/23/92 > CALIFORNI A

GULC H CERCL A SIT E ZIN C SLA G PIL E INVESTIGATIO N LEADVILLE

. COLORAD O FIGUR E 4- 1 ZIN C SLA G PIL E CURREN T SURFAC E AREA

, VOLUM E AN D ANGLE S O F REPOS E DENVE R & RI O GRAND E WESTER N RAILROA D DENVER

, COLORAD O IMORRISON-KNUDSE N CORPORATIO N FIL E NAM E (CM) ) 1893N04 8 PROJEC T SUFTIX 189 3 63 0 TAS K 0 6 |DATE:6/02/9 2

DRAWIN G NUMBE R FIGUR E 4- 1 REV

. AN

515,50 0 I

N 519,25 0

N 515,00 0

N 514,75 0

N 314,30 0 U . 4 III U J 

### LEGEN D

, . - 2 SURFAC E CONTOU R INTERVA L

— BOUNDAR Y O F VOLUM E CALCULATIO N VOLUM E CALCULATIO N Metho d o f Calculation:...

. QuickSur f Gri d Size:.........................10 X

10

35,10 0 Cubi c Yard s

SCAL E FEE T 0 5 0 10 0 15 0 2Q O TOPOGRAPH Y DIGITIZE D FROM 195 6 AERIA L PHOTOGRAPH Y B Y INTRASEARCH

. INC

.

<CPO:06/23/92 > CALIFORNI

A GULC H CERCL A SIT E ZIN C SLA G PIL E INVESTIGATIO N LEADVILLE

. COLORADO_____

_ FIGUR E 4- 2 ZIN C SLA G PIL E HISTORI C VOLUM E DENVE R & RI O GRANO E WESTER N RAILROA D DENVER

, COLORAD O IMORRISON-KNUDSE N

CORPORATIO N ril l N«M t JC«D ) 1893NQ2 0 PROJEC T SUFTI X 189 3 63 0 IDMI3/17/9 ?

DRAWIN G NUMBE R FIGUR E 4- 2 RCV

. ASla

g pil e volume s wer e calculate d usin g thre e differen t methods : averag e en d area , gri d 

### subtraction
, an d triangula r irregular networ k (TIN ) subtraction

. Th e averag e en d are a metho d generate s section s throug h th e pil e alon g predetermine d gri d lines

. Th e volum e 

### between tw o section s i s calculate d b y determinin g th e averag e are a o f eac h sectiona l fac e
an d multiplyin g i t b y th e widt h o f th e grid

. Th e volume s betwee n eac h pai r o f section s i s 

### summe d t o giv e th e tota l volum e o f th e pile

. Usin g th e Gri d Subtractio n Method

, uppe r an d lower surface s aroun d th e pil e ar e generate d b y interpolatin g elevation s a t prescribe d rectangula r gri d node s fro m existin g data

. Th e tota l 

### volum e betwee n the uppe r surfac e and a datu m for a rectangula r gri d cel l i s the n calculate d

and designate d a s fill

. The n th e volum e i s calculate d betwee n th e lowe r surfac e and a datu m fo r th e sam e cel l an d designate d a s cut

. Th e differenc e betwee n fil l an d cu t fo r eac h gri d cel l i s summe d t o giv e th e tota l volum e o f th e pile

. T h e TI N Subtractio n Metho d i s performe d similarl y t o th e gri d method
, excep t triangula r gri d cell s ar e generated
, exactl y honorin g al l o f th e actua l dat a point s surveyed

. Th e differenc e betwee n th e volum e o f fil l an d cut withi n eac h o f th e triangula r gri d cell s i s summe d t o giv e the tota l volum e o f the pile

. 4. 4 Sla g Pil e Stabilit y The stabilit y o f th e zin c sla g pile
, a s i t currentl y exists , wa s evaluate d wit h respec t t o 

### structura l stability
, deflatio n potential
, an d effect s o f freeze/tha w cycling

. Th e geotechnica l stabilit y evaluatio n wa s base d o n th e result s o f th e fiel d reconnaissanc e an d th e sla g pil e contou r map

. Th e deflatio n potentia l o f th e sla g was estimate d fro m particl e siz e informatio n an d ai r emission s calculations

. Th e effect s o f freeze/tha w cyclin g o n th e stabilit y o f th e sla g pil e wa s base d on a literatur e revie w and observed conditions

. 4.4. 1 Analysi s o f Structura l Stabilit y Th e structura l (geotechnical ) stabilit y o f th e zin c sla g pil e wa s evaluate d base d o n th e result s
o f th e fiel d reconnaissanc e task

. Angle s o f repos e wer e calculate d fro m th e topographi c survey

. 

### The zin c sla g pil e ha s bee n partiall y excavate d an d currentl y consist s o f a cor e o f welde d materia l approximatel y 1 5 fee t hig h wit h vertical face s surrounde d b y loos e material

. N o obviou s talu s wa s note d a t the zin c sla g pil e becaus e o f the highl y disturbe d natur e o f the pil e an d th e existenc e o f larg e quantitie s o f loos e material

. A t area s wher e welde d sla g MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Flnal-R I

4- 5 [Re v 001/13/93 ]outcrops

wer e observed
, onl y a trac e o f loos e materia l wa s note d a t th e pil e base

. Base d

o n thre e measurements , th e averag e angl e o f repos e i s 3 4 degree s (Figur e 4-1)

. Ther e wer e 

### n o fissure s o r faul t block s note d a t thi s pil e an d th e pil e present s n o stabilit y concern
. 4.43 Deflation/Emission s

Potentia l Emission calculation s usin g th e 199 1 meteorologica l dat a fro m th e Colorad o Mountai n Colleg e (Res-ASARCO

, 1991 ) an d the mod e o f the aggregat e siz e distributio n hav e demonstrate d tha t win d erosio n doe s no t occu r fro m th e zin c sla g pile

. Thi s conclusio n i s base d upo n standar d procedure s an d guidanc e fro m the EP A regional offic e i n Denver

, Colorad o (EPA

, 1992)

. Th e procedures
, describe d i n Sectio n 3.4.2 , wer e use d t o determin e th e frictio n velocit y (o r win d spee d a t th e pil e surface ) an d th e threshol d frictio n velocit y (minimu m win d spee d at whic h particle s wil l becom e airborne ) o f th e zin c sla g pile

. Th e result s ar e a s follows : Frictio n

Velocit y .5

5 m/se c 

### Threshol d Frictio n Velocit y 1. 0

m/se c T h e frictio n velocit y was the n compare d t o th e threshol d frictio n velocity

. A frictio n velocit y lowe r tha n th e threshol d show s tha t Leadvill e win d speed s ar e no t fas t enoug h t o caus e win d erosio n fro m th e Wester n Zin c pile

. 

### I t shoul d b e reiterate d tha t a numbe r o f factors

, no t accounte d for b y th e method
, mak e th e emissio n rat e estimate s conservative

. I t i s usefu l t o not e tha t i f a lowe r "beta " value mor e representativ e o f ai r flo w ove r roug h terrai n wa s used
, th e conversion facto r woul d b e eve n lowe r tha n 1.13

. ("Beta " valu e i s discusse d i n th e Simi u an d Scanla n attachmen t t o thes e responses. ) Th e Leadvill e sla g ha s a greate r densit y tha n th e san d an d grave l pile s at th e Midwes t sit e use d t o develo p empirica l dat a fo r th e EP A method

. Furthermore

, th e ai r density
, an d therefor e th e lifting forc e o f win d a t th e sam e speed
, i s muc h lowe r i n Leadville

. Additionally

, period s o f hig h moisture , sno w cover , an d froze n groun d als o woul d limi t th e potentia l fo r fugitiv e dus t emissions

. Th e emission s calculation s d o no t tak e int o
accoun t an y condition s othe r tha n thos e idea l fo r win d erosio n o f material

. 4.4. 3 Effect s o f Freeze/Tha w Cyclin g Literatur e wa s researche d t o determin e ho w freezin g wate r ma y disaggregat e materia l simila r t o slag
, suc h a s rock

. Also

, literatur e wa s reviewe d t o determin e i f freeze/tha w

MORRISO N KNUDSEN CORPORATIO N BB\1893\ZINCRPT\Flnal-R I

4- 6 [Re v 001/13/93 ]

### testin

g ha s bee n done o n zin c sla g o r slag-lik e material

. Materia l considere d i n th e 

### literatur e searc h include d slag
, igneou s rocks
, natura l glasse s an d vitrifie d waste

. Th e disintegratio n o f roc k du e t o pressur e exerted b y wate r freezin g i n crack s an d pore s i s calle d congelifraction

. Whe n wate r freeze s under atmospheri c conditions
, it s molecule s organize int o a rigi d hexagona l crystallin e network
, an d i t increase s nin e percent i n specifi c volume

. A s ice expands
, th e pressur e o f th e remainin g water increases , an d th e temperatur e mus t b e lowere d furthe r i n orde r t o continue thi s increas e i n pressure

. Ic e i s no t stron g 

### enoug h t o sea l water int o a fractur e an d produc e th e maximu m possibl e pressure , a s th e plasti c deformatio n o f ice i s so rapi d tha t wate r i s quickl y extrude d (Bloom

, 1978)

. Wate r i n ver y thi n crack s wil l no t freeze

, eve n a t ver y lo w temperatures , because o f th e stron g capillar y adhesio n o f th e wate r t o rock

. Mos t o f th e roc k fracture s attribute d t o 

### freezin g ar e probabl y du e t o capillar y o r monomolecula r film s o f unfroze n wate r tha t sprea d alon g pre-existin g crack s i n rocks

. Thi n film s o f wate r for m a semicrystallin e "ordered " molecula r structur e on minera l surface s that ca n pr y apar t microfracture s an d propagat e cracks

. Shallo w freezin g ma y ai d i n forcin g capillary film s o f wate r deepe r alon g tigh t joint s
an d pre-existin g microfractures

, thereb y hydrofracturin g rock s wel l belo w th e dept h o f actua l 

### freezin g (Bloom

, 1978)

. 

### Base d o n th e literatur e review , freeze/tha w cyclin g ma y hav e som e effec t o n zin c slag

. Smal l surfac e vug s o f th e zin c sla g ma y fil l wit h water tha t subsequentl y freezes

. Recurren t 

### freeze-and-tha w actio n i n th e sla g surfac e laye r coul d loose n zin c sla g fragments

, causin g eventua l breakdow n o f th e materia l t o fine r particles

. 4. 5 Chemica l Characteristic s o f Zin c Sla g Materia l 

### Th e chemica l characteristics o f th e zin c sla g material
, a s determine d b y th e analytica l 

### progra m outline d i n th e SA P an d discusse d i n earlie r sections , ar e presente d i n thi s section

. Chemica l analyse s include d tota l compositiona l analysis
, Syntheti c Precipitatio n Leachin g Procedur e (SPLP ) analysis
, an d colum n leachin g test s wit h analysi s o f th e effluent

. Compositiona l analyse s include d th e analyse s o f th e TA L metal s (minu s mercur y plu s 

### silicon)

, wate r solubl e anions , neutralizatio n potential
, sulfu r form s an d catio n exchang e capacity

. SPL P an d colum n leac h eluat e wer e analyze d fo r anion s an d TA L metal s (minu s
mercur y plu s silicon)

.

MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Rnal-R I

4- 7 [Re v 001/13/83 ]TABL E 4- 3 FREQUENC Y O F OCCURRENC E O F TA L METAL S

— ZIN C SLA G 

### Chemica l Nam e Aluminum

, tota l Antimony

, tota l Arsenic

, tota l 

### Barium

, total Beryllium

, tota l 

### Cadmium

, tota l Calcium

, tota l Chromium

, tota l Cobalt

, total 

### Copper

, total Iro n III

, tota l Lead

, tota l 

### Magnesium

, total Manganese

, total Nickel

, total Potassium

, tota l Selenium

, tota l Silicon

, Tota l Sodium

, tota l Vanadium

, total Zinc

, tota l TOTAL S Numbe r

o f 

### Detection s 4 3 4 4 4 4 4 4 4 4 4 4 4 4 4 4 0 4 4 4 4 7 9 

### Numbe r o f Analyse s 4 4 4 4 4 4 4 4 • 4 4 4 4 4 4 4 4 4 4 4 4 4
8 4 RANG E O F DETECTE D CONCENTRATION

S Minimu m Valu e (mg/kg )
21100.0 0 HSS102MO O 5.3 0 HSS102MO O 112.00 HSS104MO O 782.0 0 HSS104MO O 1.4 0 HSS104MO O 2.5 0 HSS103MO O 12500.0 0 HSS101MO O 35.9 0 HSS101MO O 9.9 0 HSS104MO O 125.0 0 HSS103MO O 108000.0 0 HSS104MO O 192.0 0 HSS103MO O 6570.0 0 HSS101MO O 51600.0 0 HSS101MO O 41.9 0 HSS104MO O 5510.0 0 HSS102MO O N / A 134000.0 0 HSS102MO O 604.0 0 HSS104MO O 44.5 0 MSS104MO O 63200.0 0 HSS101MO O 

### Maximu m Valu e (mg/kg )
22900 HSS101MO O 52. 2 HSS101MO O 41 4 HSS101MO O 142 0 HSS101MO O 2 HSS101MO O 29. 5 HSS101MO O 4220 0 HSS103MO O 70 0 HSS102MO O 19. 8 HSS102MO O 3310 HSS102MO O 19800 0 HSS102MO O 92 5 HSS102MO O 1880 0 HSS103MO O 7650 0 HSS104MO O 39 2 HSS102MO O 769 0 HSS103MO O N / A 15400 0 MSS103MO O 101 0 HSS103MO O 5 8 HSS101MO O 7000 0 HSS103MO O

*

. _ *i

. i.

. t »i-

. i4.5. 1

Compositiona l Analyse s A l l fou r sla g sample s fro m th e Wester n Zinc Smelte r are a wer e submitte d t o th e compositiona l analysi s program

. 4.5.1. 1 TA L Metal s 

### Targe t Analyt e Lis t (TAL ) metal s wer e analyze d followin g digestio n b y a U.S

. Burea u o f Mine s metho d a s the preparator y techniqu e (Burea u o f Mines

, 1980)

. Afte r digestion
, mos t metal s analyse s wer e conducte d b y Inductivel y Couple d Plasm a (ICP ) techniques
, although


### som e o f th e metal s wer e analyze d b y graphit e furnac e atomi c absorptio n (GFAA ) methods

. Th e element s analyze d b y GFA A includ e arsenic , cadmium
, lea d an d selenium

. Th e us e
o f GFA A wa s necessitate d b y matri x interferenc e problem s cause d b y the particula r digestio n flui d used

. Tabl e 4- 3 present s the frequenc y o f occurrenc e o f the elements
, alon g wit h the minimu m
an d maximu m value s o f eac h o f th e elements

. Iro n an d silico n compris e th e majorit y o f th e sla g matrix

. Iro n range s fro m 10. 8 t o 19. 8 percen t o f th e zin c sla g material
, whil e silico n range s fro m 13. 4 t o 15. 4 percent

. Manganes e value s ranged fro m 5. 2 t o 7. 7 percent

. Th e concentratio n rang e an d geometri c mea n o f eac h o f fou r primar y element s o f concer n i n zin c sla g a t th e Californi a Gulc h sit e are a s follows :

- Arsenic-11 2 t o 41 4 mg/kg

, mea n 21 1 mg/k g



### - Cadmium-2. 5 t o 29. 5 mg/kg

, mea n 14. 1 mg/k g

- Lead-19 2 t o 92 5 mg/kg

, mea n 56 8 mg/k g

- Zinc-63,20 0 t o 70,00 0 mg/kg

, mea n 66,00 0 mg/k g
4.5.1. 2 Anion s Water-solubl e anion s chloride
, sulfate

, an d nitrate/nitrit e wer e analyze d i n the zin c sla g 

### samples

. Althoug h carbonat e wa s not directl y measure d i n the water-solubl e extracts , it s concentratio n wa s calculate d fro m th e neutralizatio n potentia l results
, whic h ar e reporte d

a s tota l calcium carbonate

. Th e anion s ar e reporte d i n solid units , mg/kg

, b y back

calculatio n fro m th e analyse s conducte d i n th e water-solubl e extract

. Th e mos t prevalen t anio n i n th e zin c sla g i s th e carbonat e anio n wit h a mea n o f 79,20 0 

### mg/k g a s CaCO
3 

### o r abou t 8 percen t o f th e tota l mas s o f th e material

. Th e rang e o f concentration s o f carbonat e i s fro m 58,80 0 t o 100,20 0 mg/kg

. The secon d mos t prevalen t water-solubl e anio n i s sulfate

. Range s an d mean s fo r th e anion s ar e liste d below :
MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRFT\Final-R I

4- 8 [Re v 001/13/93 )

### TABL E 4- 4



### Sampl e I D 

### Neutralizatio n

Potentia l Aci

d Generatio n 

### Potentia l du e t o Pyriti c Sulfu r 

### N e t

Aci d Formin g 

### Potentia l HSS101MO O Zin c Sla g 

### HSS102MO O Zin c Sla g HSS103MO O Zin c Sla g HSS104MO O Zin c Sla g 12

5 14 9 9 8 16 7 0.3

0 1.3 0 0.3 0 0.6 0 -124.7 0 -147.7 0 -97.7 0 -166.4 0



### zinctb!s\tbW- 4 6/29/9 2

### -

Sulfat e - 1,46 3 t o 13,04 0 mg/kg

, mea n 4,09 9 mg/k g

- Chlorid e - 2. 3 t o 20. 8 mg/kg

, detecte d 2 time s ou t o f 4

- Nitrat e - 5. 8 t o 45. 4 mg/kg

, mea n 20. 5 mg/k g

- Nitrit e - < 1. 0 t o 2. 1 mg/kg

, detecte d 1 tim e ou t o f 4
4.5.1. 3 Sulfu r Form s Sulfu r form s wer e determine d b y EP A Metho d 3.2. 4 an d 3.2. 6 (EPA

, 1978 ) fo r input t o calculation s o f acid-bas e accounting

. Tota l sulfu r i s comprise d o f pyriti c sulfur

, sulfate

, an d 

### othe r non-extractabl e sulfu r forms

. Th e mea n concentratio n fo r tota l sulfu r i s 0.4 1 percent , wit h sulfat e sulfu r th e larges t fractio n b y weight o f tota l sulfur

. Th e followin g provide s a breakdow n o f th e sulfu r for m concentratio n ranges :

- Tota l sulfur--0.3 4 t o 0.55%
, mea n 0.41 %



### - Sulfat e sulfur-0.0 1 t o 0.54%
, mea n 0.13 %

- Pyriti c sulfur-0.0 1 t o 0.04%
, mea n 0.012 %

- Non-extractabl e sulfur~0.0 3 t o 0.22%
, mea n 0.10 % Evaluatio n o f th e result s fo r pyriti c sulfu r versu s tota l sulfu r indicat e that pyriti c sulfu r average s 9. 9 percen t o f tota l sulfu r fo r al l o f th e sla g sample s collected

. Th e geometri c mea n fo r pyriti c sulfu r wa s calculate d usin g non-detec t value s a s on e hal f o f the quantitatio n limit

. For us e i n acid-bas e accounting , the percen t o f pyriti c sulfu r i s converte d t o unit s o f ton s o f CaCO 3 equivalent s pe r 100 0 ton s o f materia l (t/kt ) b y multiplyin g b y 31.25 , yieldin g potentia l acidity

. Th e potentia l acidit y du e t o pyriti c sulfu r i s presente d i n Tabl e 4-4

. Th e geometri c mea n potentia l acidit y du e t o pyriti c sulfu r fo r th e zin c sla g sample s i s 0. 5 t/kt

. Thes e value s indicat e that th e zin c sla g ha s a lo w potentia l fo r aci d generatio n du e t o th e lo w level s o f pyriti c sulfur

. 4.5.1. 4 Neutralizatio n

Potentia l an d Acid-Bas e Accountin g Neutralizatio n Potentia l (NP ) wa s measure d b y EP A Metho d 3.2. 3 (EPA

, 1978 ) an d reporte d i n unit s o f ton s o f CaCO 3 pe r 100 0 ton s o f materia l (t/kt)

. Thes e value s are 

### presente d i n Tabl e 4-4

. Th e N P fo r th e zin c sla g material showe d tha t i t ha s a mea n neutralizatio n potentia l o f 13 2 t/kt

, rangin g fro m 9 8 t o 16 7 t/kt

. Acid-bas e accountin g i s a techniqu e develope d fo r identifyin g potentiall y toxi c acidit y level s


### o f pyriti c material s i n surfac e minin g overburden

. Th e weatherin g o f pyriti c overburde n material s ca n produc e aci d ove r time , thereb y lowerin g th e p H an d creatin g a n environmen t 

### conduciv e t o leachin g metals

. Th e net acid-bas e accoun t o f a min e overburde n i s define d

MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Rnal-R t

4- 9 [Re v 0 01/13/93 ]a s it s maximu m potentia l acidit y minu s it s neutralizatio n potential
, wit h bot h expresse d i n unit s o f ton s calcium carbonat e (CaCO3 ) equivalent s pe r 100 0 ton s o f material

. Potentia l acidit y i s equivalen t t o th e amoun t o f acidit y tha t ca n b e generate d fro m sulfu r compound s (generall y sulfide ) an d i s calculate d usin g th e measure d pyritic sulfu r values

. Neutralizatio n potentia l i s th e bufferin g capacit y o f th e material

. Th e differenc e betwee n potentia l acidit y 

### an d neutralizatio n potentia l i s ne t aci d generatio n potential

. Eac h o f thes e value s for th e sla g sample s ar e presente d i n Tabl e 4-4

. Accordin g t o Mine Spoil Potential fo r Soil an d Water Quality (EPA

, 1974)

, pag e 128 , "Fro m th e acid-bas e account , potentiall y toxi c materia l i s define d a s a roc k o r eart h materia l havin g
a ne t potentia l deficienc y o f 5. 0 ton s o f calciu m carbonat e equivalen t o r mor e pe r 1,00 0 ton s
o f material. " A ne t acid-formin g potentia l les s tha n 5. 0 t/k t indicate s exces s neutralizatio n potentia l i n 

### relatio n t o the potentia l aci d generation

. Al l zin c sample s showe d a ne t acid-formin g potentia l les s tha n 5.0 ; the geometri c mea n wa s -13 2 t/kt

. Thus

, the sla g sample d i s not potentiall y aci d toxi c du e t o aci d generatio n potential

. 4.5.1. 5 Catio n Exchang e Propertie s 

### Catio n Exchang e Capacit y (CEC ) i s a measur e o f how readil y a material wil l sor b cation s ont o it s surfac e o r int o it s matrix

. Th e CE C wa s measure d usin g EP A metho d 908 0 (EPA

, 1986)

, i n whic h result s ar e expresse d i n milliequivalent s (meq ) pe r 10 0 gram s o f material

. 

### Th e materia l teste d ha s a lo w CEC

, wit h value s o f 2.0 , 4.9 , 5. 9 an d 15.2 meq/lOOg

. Th e CE C result s fo r the fou r zin c sla g sample s sho w a geometric mea n o f 5. 4 mg/lOOg

. 4.5. 2 Leachin g Analyse s 

### Tw o type s o f leachin g test s wer e performe d o n zin c slag

. One method
, the Syntheti c Precipitatio n Leac h Procedur e (SPLP ) i s a liqui d shak e extractio n tes t develope d t o simulat e 

### leachin g o f min e wast e impacte d b y acidi c precipitation

. The othe r tes t i s a laborator y colum n leac h tes t designe d t o simulat e percolatio n o f precipitatio n throug h th e material

. 4.5.2. 1 Syntheti c Precipitatio n Leachin g Procedur e Th e SPL P (EP A Metho d 1312 ) wa s conducte d o n eac h o f th e zin c sla g sample s collected

. Th e sampl e siz e wa s increase d t o 1 kilogra m rathe r tha n th e 10 0 gra m sampl e specifie d b y 

### th e metho d t o avoi d particl e siz e reduction

. Particl e siz e reductio n t o les s tha n 9.5mm , a s calle d fo r i n th e method
, wa s no t conducte d o n thes e sample s s o a s t o mimi c in-sit u condition s o f the pile s a s closel y a s possible

. MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Rnal-R I

4-1 0 [Re v 001/13/93 ]T h e

SPL P metho d call s fo r comparison s o f eluat e concentration s t o applicabl e regulator y thresholds
, bu t doe s no t stat e wha t thes e threshold s are
. Becaus e th e tes t mos t closel y resemble s the TCL P o r E P toxicit y tests , regulator y threshold s associate d wit h thes e test s wer e utilized

. Th e result s fo r al l element s fo r al l zin c sla g sample s wer e belo w th e toxicit y 

### characteristi c criteri a liste d i n 4 0 CF R 261.24

. Th e maximu m value fo r eac h o f th e eigh t metal s fo r whic h toxicit y characteristi c criteri a exis t wa s generall y mor e tha n tw o order s o f magnitud e lowe r tha n th e criterion

. Th e exceptio n t o thi s i s manganese , whic h wa s mor e tha n on e orde r o f magnitud e lower

. Th e followin g summar y compare s th e mea n an d maximu m value s o f th e leachat e t o th e toxicit y criteri a o r 10 0 time s th e secondar y drinkin g wate r standards : 

### Elemen t Arseni c Bariu m Cadmiu m Zin c Manganes e Iro n 

### Toxicit

y Criteri a 5. 0 mg/ 1 10 0 mg/ 1 1. 0 mg/ 1 50 0 mg/1 * 5. 0 mg/1 * 3 0 mg/1 * 

### Mean

Valu e 0.03 0 mg/ 1 0.08 4 mg/ 1 0.00 2 mg/ 1 0.06 3 mg/ 1 0.01 6 mg/ 1 0.01 0 mg/ 1 Maxinu

m Valu e 0.05 1 mg/ 1 0.14 1 mg/ 1 0.00 6 mg/ 1 1.0 4 mg/ 1 0.14 1 mg/ 1 0.02 2 mg/ 1 10 0 time s secondar y drinking-wate r standards

. 

### Chromium

, copper , lead
, seleniu m an d silve r value s wer e belo w detectio n limit s fo r al l fou r samples

. Th e geometri c mean s for arsenic , cadmium and iro n wer e calculate d usin g non
detec t value s ( 2 o f 4 fo r iro n an d 1 o f 4 fo r arseni c an d cadmium ) a s on e hal f th e quantitatio n limit

. 

### 4.5.2. 2 Colum n Leac h Studie s Colum n leac h testin g wa s conducte d on on e zin c sla g sample

. Th e materia l i n th e column
wa s subjecte d t o one-hou r leachin g cycles
, eac h representin g a one-inc h rainfal l event

. The colum n criteri a wer e a s follows : Tes t Materia l Zin c Sla g Mod

e Downflo w Colum n

Diamete r (in. ) 8 

### Volum e

o f one-inc h o f rainfall ) 82 3 Th e lixivian t use d fo r th e colum n leac h testin g wa s th e simulate d precipitatio n fo r area s wes t

o f th e Mississippi

, a s specifie d i n Metho d 131 2 o f SW-846

. Th e precipitatio n flui d i s mad e b y addin g a 60/4 0 weigh t percen t mixtur e o f sulfuri c an d nitri c acid s t o deionize d wate r unti l th e p H i s 5.0 0 ±0.0 5 units

. Th e flui d wa s prepare d i n a 55-gallo n polyethylen e dru m 

### b y addin g approximatel y 2 m l o f th e aci d mixtur e t o 5 0 gallon s o f deionize d wate r an d mixing

. Du e t o th e lac k o f bufferin g capacit y i n th e water, th e p H droppe d t o abou t 4. 5 an d

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Final-R I 4-1 1 [Re v 001/13/93 ]wa

s readjuste d t o p H 5.0 0 ±0.0 5 b y th e dropwis e additio n o f 1 0 percen t sodiu m hydroxid e 

### (NaOH)

. The simulate d precipitatio n wa s introduce d t o the colum n ove r a one-hou r interval
, followe d b y a one-hou r desaturation/aeratio n

perio d durin g whic h th e lixivian t wa s allowe d t o drai n fro m th e tes t material

. Th e test s too k plac e ove r a perio d o f two hundre d hours
, 

### correspondin g t o one hundre d rainfal l events

. Considerin g that Leadvill e receive s abou t twelv e an d on e hal f inche s o f rainfal l pe r yea r th e colum n leac h tes t cycle s corresponde d 

### t o eight year s o f rainfall

. Th e followin g tabl e present s loadin g dat a fo r th e zinc-sla g column : Tes t Weigh t

Packe

d Tota l

Por

e Materia l Materialfg

) Lengthfiir i

Volfm n

VcKmf

t Zin c Sla g 8,81 3 1 9 15,64

2 3,80

0 Effluen t was collecte d fro m eac h o f th e precipitatio n events

. Upo n collection
, pH

, Eh

, an d conductanc e measurement s wer e mad e usin g calibrate d probe s connected t o pH/m v an d conductanc e meters

. Afte r thes e measurement s wer e completed
, th e sampl e wa s filtere d throug h Whatma n #4 0 (S^m ) filte r paper

. Th e sample s wa s spli t int o tw o separat e containers ; on e fo r anion s analysi s an d th e othe r fo r metal s analysis

. Th e sample s fo r metal s analysi s wer e preserve d wit h nitri c aci d t o a p H les s tha n 2.0

. 

### A t th e completio n o f on e hundre d cycles
, th e por e volum e o f th e colum n wa s determined

. Thi s measuremen t wa s mad e b y pumpin g wate r t o th e to p o f th e tes t materia l an d the n measurin g th e volum e o f wate r collecte d a s th e wate r leve l wa s lowere d t o th e botto m o f 

### th e test material

. Tabl e 4- 5 summarize s th e analytica l result s fo r selecte d metal s an d anion s fro m th e colum n leac h test

. Figure s 4- 3 an d 4- 4 depic t i n graphica l for m th e concentration s o f selecte d 

### metal s an d anion s a s a functio n o f effluen t numbe r (precipitatio n event)

. Th e complet e result s o f th e colum n leac h testin g ar e presente d i n Appendi x Bl

.

4. 6 Analytica l Dat a Validatio n 

### Dat a validatio n wa s performe d o n 10 0 percen t o f th e analytica l dat a reporte d b y th e laboratory

. CL P method s wer e evaluate d usin g accepte d criteri a an d control limit s define d

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Final-R I

4-1 2 [Re v 0 01/13/93 ]

### TABL E 4- 5



### Leachin g Even t # Lea d ug/ l 

### Cadmiu m ug/ l Arseni c 

### ug/ l Zin c 

### ug/ l 

### Bicarbonat e mg/ l SuKat e 

### mg/ l

5 2 5 5 0 7 5 10 0 3 1 u 

### 3 1 u 41. 9 

### 3 1 u 4 4 14 1 12 6 76. 5 42. 2 20. 1 49 u 49 u 49 u 49 u 

### 53. 6 3150 0 2620 0 1390 0 720 0 368 0 29. 2 13. 1 14. 1
14. 7 174 2 147 9 107 9 428. 7



### u - non-detec t

— - no t analyze d

zinctbls\tbl4- 6

6/29/9 2

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T CONCENTRATIO N

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### 0 1



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## z c n ^ 

## z C O 

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## o c z r C O H C O



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### - m \ C Ob y th e draf t Laboratory Data Validation, Functional Guidelines fo r Evaluating Inorganics Analyses (EPA

, 1988b ) (Functiona l Guidelines ) an d th e USEPA Contract Laboratory Program, Statement o f Work for Inorganic Analysis (EPA

, 1990a ) (SOW)

. Non-CL P method s
wer e validate d usin g criteri a consistent wit h guideline s applicabl e t o thos e methods

. Contro l limit s specifie d i n th e Functiona l Guideline s wer e use d a s guidanc e i n th e evaluatio n o f non
CL P qualit y contro l dat a fro m duplicates
, spikes
, an d laborator y control samples

. Th e sampl e grou p fro m eac h dat a packag e i s referre d t o a s th e sampl e deliver y grou p (SDG)

. A SD G Analytical Data Validation Summary repor t wa s prepare d fo r eac h SD G an d include s thre e sections :
1

. A summar y o f th e sampl e numbers
, sampl e typ e an d matrix , method s o f analysis
, and overal l dat a useabilit y 2

. Th e CL P dat a validatio n result s 3

. The non-CL P dat a validatio n results—laborator y

performanc e o n eac h o f the CL P Qualit y Assurance/Qualit

y Contro l (QA/QC ) criteri a ar e summarize d

an d an y dat a reportin g o r functiona l problem s i n th e dat a packag e ar e 

### discusse d i n detai l Precision

, accuracy , representativeness ,

completeness
, an d comparabilit y (PARCC ) parameter s fo r analytica l dat a wer e develope d a s par t o f th e overal l dat a qualit y objective s (MK

, 1991b)

. Th e dat a validatio n proces s play s a n integra l par t i n determinin g i f analytica l 

### dat a met the PARC C criteria

. Validatio n o f th e analytica l dat a showe d tha t al l dat a collecte d i s usabl e fo r th e intende d purpose

. Usabl e dat a i n som e case s i s qualifie d b y the laborator y and/o r the dat a reviewe r
an d th e qualifier s place d o n th e dat a shoul d b e considere d whe n assessin g th e relativ e erro r 

### i n an y particula r dat a point

. Overall

, th e dat a qualit y objective s se t fort h fo r thi s projec t wer e obtaine d wit h greate r tha n 

### 98 % o f th e dat a bein g availabl e fo r quantitativ e usage

. Appendi x E l present s th e SD G summar y reports , whic h includ e sampling
, receipt , an d 

### analytica l date s for eac h sample
, and a summar y o f al l analytica l dat a considere d t o b e 

### quantitativ e estimate s base d o n validatio n parameters

.

MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Final-R I

4-1 3 [Re v 001/13/93 ]4.6. 1

CL P Dat a Validatio n 

### The followin g dat a qualit y issue s wer e addresse d i n the dat a validatio n an d revie w proces s fo r CL P analyses

. Fiel d an d Transportatio n OA/O C Documentatio n wa s reviewe d t o verif y tha t uninterrupte d chain-of-custod y protoco l wa s followe d an d reporte d i n a manne r consisten t wit h th e SO W criteria

. Holding Time s A s state d previously
, a listin g o f samplin g date
, laborator y receip t date
, an d analysi s dat e
wa s prepare d an d summarize d fo r eac h sampl e i n th e SD G an d reporte d i n Appendi x El

. Th e tim e elapse d betwee n th e samplin g an d analysi s date s wa s compare d wit h holdin g tim e criteri a require d b y th e SOW

. A genera l summar y o f holdin g tim e complianc e i s provide d i n th e tex t o f th e report

. Initia l an d Continuin g Calibratio n Verificatio n 

### Start-u p calibratio n record s generate d b y th e laborator y wer e reviewe d an d validate d t o demonstrat e that th e instrument s wer e capabl e o f producin g acceptabl e quantitativ e data

. Continuin g Calibratio n an d Preparatio n Blank s 

### Blan k dat a wa s assesse d t o determin e th e existenc e an d magnitud e o f an y contaminatio n 

### tha t ma y hav e bee n introduce d durin g th e calibratio n or sampl e preparatio n process

. Interferenc e Chec k Sampl e Interferenc e chec k sampl e result s wer e reviewe d t o verif y that instrumen t inter-elemen t and background correctio n factor s wer e correct

. 

### Spike d Sampl e Recoverie s Spike d sampl e result s wer e reviewe d t o evaluat e th e accurac y o f sampl e result s an d t o evaluat e the effec t eac h sampl e matri x ha d o n the digestio n and measuremen t methodology

. Dat a qualifier s applie d b y th e laborator y wer e reviewe d t o ensur e the y wer e correctl y 

### applie d an d reported

. Graphit e Furnace-Atomi c Absorptio n Spectroscop y (GFAA ) Duplicate s Duplicat e injection s consistin g o f sampl e an d spiked-sampl e ar e required fo r GFA A analysis

. Duplicat e analysi s i s performe d b y th e laborator y t o establish th e precisio n an d accurac y o f

MORRISO N KNUDSE N CORPORATIO N B8\1883\2INCRPT\Final- R

4-1 4 [Re v 001/13/93 )

### individua l

analytica l determinations

. Duplicat e recoverie s presente d b y the laborator y wer e recalculate d b y th e reviewe r and duplicat e value s wer e verifie d fro m GFA A raw dat a t o ensur e that qualifier s wer e correctl y applied

. 

### Duplicat e Recoverie s 

### Analyse s o f lab-choic e duplicat e sample s wer e evaluate d t o determin e th e laborator y precisio n base d o n th e sampl e matrix

. Duplicat e recoverie s wer e recalculate d an d dat a qualifier s verified

. Laborator y Contro l Sampl e (LCS ) 

### Th e LC S sampl e result s wer e verifie d and evaluate d t o ensur e tha t overal l analytica l and 

### preparatio n performanc e i n th e laborator y wer e adequate

. Metho d o f Standar d Addition s (MSA ^ Result s MS A i s require d fo r quantificatio n o f analyte s determine d b y GFA A tha t d o no t mee t spik e
recover y criteria

. Spik e recover y dat a wer e reviewe d t o determin e i f MS A wa s correctl y applied
, a s needed

. Statistica l varianc e o f th e MS A result s wa s evaluate d t o determin e i f 

### th e dat a wer e useabl e withou t qualification

. Inductivel y Couple d Plasm a (IPC ) Spectrophotometr y

Seria l Dilutio n Seria l dilutio n i s required t o determin e whethe r significan t physica l o r chemica l 

### interference s existe d du e t o sampl e matrix

. Result s fo r hig h concentratio n analyte s wer e reviewe d t o ensur e seria l dilutio n result s wer e correctl y calculate d an d qualified

, a s required

. 4.6. 2 Non-CL P Dat a Validatio n Th e followin g dat a qualit y issue s wer e addresse d i n th e dat a validatio n an d revie w proces s fo r non-CL P analyses

. Holdin g Time s A listin g o f samplin g date
, laborator y receip t date
, an d analysi s dat e wa s prepare d fo r eac h 

### sampl e i n th e SD G (Appendi x El)

. Th e tim e elapse d betwee n th e samplin g an d analysi s date s wa s compare d wit h holdin g tim e criteri a require d b y 4 0 CF R 136 , i f applicable

. A genera l summar y o f holdin g tim e complianc e b y the laborator y fo r eac h analytica l metho d 

### i s presente d i n th e SD G report

.

MORRISO N KNUDSEN CORPORATIO N BB\1893\ZINCRPT\Final- «

4-1 5 [Re v 001/13/93 ]

### Standar d

OA/O C fo r Individua l Analyte s o r Method s Th e applicabilit y o f QA/Q C analysi s provide d b y th e laborator y wa s compare d t o metho d specifi c o r industr y accepte d standard s a s required

. Contro l limit s specifie d fo r CL P analysi s
o f standards
, duplicate s an d spike s wer e generall y applie d t o non-CL P methods

.

MORRISO N KNUDSE N CORPORATIO N B8\1893\ZINCRPT\Rn«l-R I

4-1 6 [Re v 0 01/13/93 )5. 0

INTERPRETATIO

N O F RESULT S Th e followin g sectio n o f thi s R I repor t present s th e interpretatio n o f result s develope d fro m zin c sla g sampl e collectio n an d analyse s activities

. Th e releas e mechanism s o f primar y
concer n investigate d durin g the Zinc Sla g Pil e R I wer e leaching
, win d erosion , runof f o f sla g particles
, an d transpor t b y huma n activities

. (Direc t contac t ha s bee n discounte d a s a releas e mechanism fo r sla g pile s i n EPA' s Preliminary Baseline Human Health Risk 

### Assessment [EPA

. 1991a])

. Th e environmenta l medi a potentiall y impacte d b y thes e releas e mechanism s ar e water , soil
, an d air

. A s dat a ar e obtaine d fro m the speciatio n and other site-relate d program s additiona l dat a analyse s o f potentia l releas e mechanism s an d impact s a s the y relat e t o zin c sla g ma y b e performed

. I f thi s additiona l dat a affect s interpretations , a n addendu m t o th e R I repor t wil l 

### b e prepared

. 5. 1 Statistic s Statistica l analyse s wer e use d t o determin e relationship s betwee n elementa l meta l concentration s i n zin c sla g sample s an d thos e concentration s i n th e populatio n o f al l sla g samples

. Th e statistica l procedure s wer e performe d o n tota l compositiona l result s o f th e fou r primar y element s o f concer n (lead

, arsenic , cadmiu m an d zinc)

, a s wel l a s ke y element s
o f the sla g matri x (e.g.

, aluminum
, calcium
, copper , iron , manganes e an d silicon)

. The zin c sla g dat a se t consiste d o f th e fou r sample s collecte d fro m th e Wester n Zin c sla g pile

. Th e 

### type s o f statistica l method s ar e describe d i n Sectio n 5.1.1 , an d th e result s ar e presente d i n Sectio n 5.1.2

. 5.1. 1 Methodolog y T h e type s o f statistica l procedure s include d th e following :

- Summar y Statistic s

- Cumulativ e Distributio n Function s

- Histogram s

- Analysi s o f Varianc e

- Cumulativ e Probabilit y Plot s

- Correlatio n Analysi s

MORBISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Final-R I

5- 1 [Re v 0 01/13/93 )Statistica l

analyse s wer e performe d o n th e discret e zin c sla g dat a se t a s wel l a s o n th e lea d sla g dat a sets , fo r comparativ e purposes

. Summar y statistic s compile d fo r eac h o f th e dat a set s includ e th e range , average , geometri c mean , minimu m an d maximum

. Th e followin g tabl e list s th e dat a set s utilize d an d th e numbe r o f sample s i n eac h o f th e dat a 

### sets : Arkansa s Valle y (AV ) Water-Quenche d Fine s 4 A V Sorte d Fine s 4 A V Air-Coole d 6 * A V Ballast-Size d 4 A V Ol d Slag 2 Harriso n Surfac e 4 Harriso n Ol d Sla g 2 

### L a Plat a Surfac e 5* * L a Plat a Ol d Sla g 3* * 

### Evan s Gulch/Georgi a Gulch 4 Wester n Zin c Sla g 4 Subsla g Materia l 1 9 'include s tw o duplicat e sample s 

### **include s a n additiona l sampl e collecte d fo r colum n leachin g test s
5.1 2 Statistica l Result s T h e result s o f th e statistica l analyse s confir m tha t th e constituent s withi n th e sla g sample s
ar e log-normall y distributed ; therefore

, geometri c mean s hav e bee n use d t o repor t results

. Lognormalit y wa s determine d fro m th e dat a se t containin g al l sla g sample s (4 2 samples)

, not fro m individua l dat a subsets

. The individua l subset s wer e assume d t o b e lognorma l 

### base d on th e observatio n tha t th e entir e dat a se t i s lognormal

. Th e followin g discussio n i s base d o n summar y statistics , analyse s o f variance , an d cumulativ e distributio n functions

. Arseni c Arseni c wa s detecte d i n eac h o f th e sla g sample s analyzed

. The rang e o f concentration s 

### varie s fro m 9. 9 t o 2,16 0 mg/kg

. Th e geometri c mea n o f al l sla g sample s analyze d i s 21 7 mg/kg

. Th e zin c dat a set ha s a geometri c mea n o f 21 1 mg/kg

, whic h i s no t significantl y 

### differen t tha n th e dat a se t a s a whole

. MORRISON KNUDSE N CORPORATION BB\1893\ZINCRPT\Final-R I

5- 2 [Re v 0 01/13/93 )Cadmiu m Cadmiu m wa s detecte d i n 3 3 o f th e 4 2 sla g sample s analyzed
, whic h i s abou t 7 9 percen t o f th e samples

. Th e rang e o f detecte d value s varie s fro m a lo w o f 2. 5 mg/k g t o a hig h o f 3 7 

### mg/kg

. Th e mea n o f al l concentration s i s 4.9 3 mg/kg

. Becaus e o f th e narro w rang e o f 

### value s for cadmium
, n o discernabl e differenc e i n population s ca n b e see n fro m th e data
, althoug h th e zin c sample s ar e amon g th e highes t concentration s wit h a mea n o f 14. 1 mg/kg

. Lea d Tota l lea d wa s detecte d i n eac h o f th e 4 2 sla g sample s analyzed

. Th e concentration s o f tota l lea d range d fro m a low o f 19 2 mg/k g t o a hig h o f 30,200 mg/kg

, or 3 percen t lead

. Th e 

### geometri c mea n o f th e sample s wa s 6,66 0 mg/kg

. Th e Wester n Zin c pil e showed th e lowes t

mea n concentration s for tota l lea d a t 56 8 mg/kg

, rangin g fro m 19 2 t o 92 5 mg/kg

. Zin c Zin c wa s detecte d i n al l 42 o f th e sla g sample s analyzed
, rangin g fro m 9,80 0 t o 77,30 0 mg/kg

. Th e mea n o f th e value s i s 38,60 0 mg/kg

. Th e zin c sla g pil e dat a se t showe d th e highes t mea n concentratio n o f 66,00 0 mg/kg

. Calciu m Calciu m wa s detecte d i n al l o f th e 4 2 sla g sample s analyzed
, wit h a rang e o f concentratio n fro m 12,50 0 t o 145,00 0 mg/kg

. The mea n o f al l sla g sample s i s 83,00 0 mg/kg

. The mea n 

### concentratio n o f the zin c pil e i s distinctl y lowe r tha n othe r piles
, at 19,10 0 mg/kg

. Coppe r Coppe r wa s detecte d i n eac h o f th e 4 2 sla g sample s submitte d for analysis
, wit h a rang e o f 12 5 t o 3,31 0 mg/kg

. The geometri c mea n o f the coppe r value s i s 1,39 0 mg/kg

. The mea n valu e o f th e zin c sla g i s 57 0 mg/kg

. Iro n 

### Tota l iron , detecte d i n eac h o f th e samples
, range s fro m 10. 8 t o 33. 2 percen t o f th e sla g matrix

. Th e mea n valu e i s 23. 8 percent , indicatin g that iro n i s a majo r constituen t o f th e slag

. Th e Wester n Zin c sla g wit h a mea n o f 15. 7 percent , i s lowe r i n iro n tha n othe r dat a sets

.

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Flnal-R I 5~ 3 (Re v 001/13/93 ]

### Manganes e Manganese

, als o detecte d i n eac h o f th e 4 2 sla g sample s analyzed
, range s fro m a lo w o f 4,85 0 t o a maximu m o f 76,50 0 mg/kg

. Th e mea n o f al l value s i s 19,00 0 mg/kg

. Th e mea n concentratio n o f th e Wester n Zin c samples
, 58,40 0 mg/kg

, i s elevate d wit h respec t t o th e othe r sla g samples

. Iico n Silico n wa s detecte d i n eac h o f th e 4 2 sla g sample s collected
, wit h tota l concentratio n value s rangin g fro m 101,00 0 t o 154,00 0 mg/k g o r 1 0 t o 1 5 percent

. Th e geometri c mea n o f al l 

### sample s i s 130,00 0 mg/kg

. The dat a i s relativel y unifor m wit h mean s fo r al l o f th e dat a set s between 108,00 0 an d 141,75 0 mg/kg

. Th e geometri c mea n fo r th e Wester n Zin c sample s i s 14.2%

. 5.1.3 Cumulativ e Probabilit y Plot s Cumulativ e probabilit y plottin g i s a metho d use d t o displa y th e dat a i n a wa y that wil l 

### identif y th e variou s population s withi n a dat a set

. A norma l cumulativ e probabilit y plo t consist s o f a n arithmeti c horizonta l axi s an d a cumulativ e probabilit y vertica l axi s scale d s o that th e distributio n functio n wil l plo t a s a straigh t line

. A change i n slop e betwee n linea r segment s o f a distributio n o f value s represent s differen t populations

. Plot s o f th e concentration s o f eac h elemen t analyze d i n th e sla g and subsla g sample s are provide d i n Appendi x C

, a s ar e ran k correlatio n analysi s backu p data

. Fro m thes e plots
, th e range s o f concentration s representin g variou s population s wer e identified

. Th e range s o f concentration s assigne d t o thes e population s ar e summarized i n Tabl e 5-1 ; the populatio n t o whic h eac h concentratio n value belong s i s indicate d i n Table s 5-2 , 5- 3 an d 5-4

. A s th e dat a plotte d wer e no t transforme d prio r t o generatin g cumulativ e probabilit y plots
, break s i n th e slop e o f th e lines bu t d o no t hav e significanc e othe r tha n the y appea r t o represen t differen t populations

. Relationship s betwee n differen t element s wer e no t evident 

### fro m th e collecte d data

. Tha t is, i f a certai n se t o f sample s wer e groupe d i n a give n populatio n fo r on e element
, a secon d elemen t fo r that se t o f sample s woul d als o b e expecte d t o fal l int o a lik e populatio n grouping

. Upo n examinatio n o f th e data
, thes e correlations wer e no t evident an d thi s analysi s wa s no t carrie d further

. Therefore

, th e population s ar e designe d onl y t o provid e grouping s o f dat a i n fou r distinc t set s fo r eac h 

### element

. Certai n elements
, base d upo n th e cumulativ e probabilit y plots
, di d no t appea r t o

MORRISO N KNUDSEN CORPORATIO N BB\1883\ZINCRPT\Flnal-R I

5- 4 (Re v 0 01/13/93 ]TABLES-1

. Concentratio n Range s o f Populations 

### fo r Analyse s o f Sla g Determine d fro m Cumulativ e Probabilit y Plot s i n Appendi x E

. Elemen t Aluminum

, mg/k g Calcium

, mg/k g Chloride

, mg/k g Iron

, mg/k g Magnesium

, mg/k g Manganese

, mg/k g Nitrate

, mg/k g Nitrite

, mg/k g Potassium

, mg/k g Silicon

, mg/k g Sodium

, mg/k g Sulfete

, mg/k g Antimony

, mg/kg

. Arsenic

, mg/k g Barium

, mg/k g Beryllium

, mg/k g Cadmium

, mg/k g Chromium

, mg/k g Cobalt

, mg/k g Copper

, mg/k g Populatio n

1 mi n 13,10 0 1,97 0

< 1 14,00 0 1,90 0 65 0

< 1

< 1 3,00 0 100,00 0 17 0 2 9

< 5

< 4 34 6 0. 3 <0. 4 6 <0. 8 2 1 ma x 20,70 0 18,90 0 4 33,00 0 4,90 0 1,90 0 9 4 3,70 0 113,00 0 101 0 8 2

3 1 5 5 78 2 0.9 7 <0. 4 44.3 4. 9 13 7 Populatio n

2 mi n 21,10 0 42,20 0 8 108,00 0 5,70 0 2,50 0 2 0

- 4,40 0 121,00 0 1,05 0 13 2

4 6 11 2 91 7 1. 0 2 4 5 7. 2 26 1 ma x 25,30 0 83,80 0 20. 8 220,00 0 7,90 0 10,00 0 2 0

- 9,10 0 139,00 0 2,10 0 48 0

9 9 41 4 1,88 0 1. 3 1 3 8 1 41. 1 60 2 Populatio n

3 mi n 30,90 0 92,80 0 3 9 226,00 0 8,50 0 11,00 0 22. 7

- 18,00 0 142,00 0 5,10 0 50 8

10 8 42 7 2,07 0 1. 4 1 4 13 2 62. 6 76 8 ma x 63,40 0 117,00 0 3 9 251,00 0 19,00 0 26,00 0 45. 4

- 22,00 0 154,00 0 8,90 0 88 0

19 7 54 9 2,87 0 2. 0 1 8 68 4 75. 4 1,73 0 Populatio n

4 mi n

- 121,000

- 260,00 0 24,00 0 30,00 0

-

- 24,00 0 169,000 13,80 0 1,00 0

24 3 84 2 3,48 0 3. 4 18. 9 94 3

- 1,94 0 ma

x

- 145,00 0

- 332,00 0 32,00 0 76,50 0

-

- 28,00 0 211,00 0 13,800 13,04 0

84 2 2,16 0 4,95 0 3. 4 3 7 1,21 0

- 3,31 0Tabl e 5-1 , Pag e 2 o f 2 Elemen t Lead

, mg/k g Nickel

, mg/k g Selenium

, mg/k g Vanadium

, mg/k g Zinc

, mg/k g Aci d Gen. 1 Cat

. Ex. 2 Neutral. S/Pyrite

, % S/Sulfate

, % S/Non-Ext.

, % S/Total

, % Populatio n

1 mi n 8 5

< 3

< 2 8 18 8

<0. 3 0. 4

< 1 <0.0 1 <0.0 1 <0.0 1 <0.0 1 ma x 92 5 3. 3 11. 2 4 0 1,29 0

<0. 3 1. 4 8 4 0.0 1 0.0 2 0.3 0 0.0 4 Populatio n

2 mi n 1,59 0 3. 7 4 4 44. 5 9,80 0

0. 6 1. 8 9 8 0.0 2 0.1 9 0.5 0 0.3 4 ma x 2,65 0 8. 5 9 4 10 3 33,90 0

3 5. 9 30 0 0.0 9 0. 8 0.7 5 2. 0 Populatio n

3 mi n 7,58 0 10. 2

- 11 7 37,20 0

4. 7 6. 1 33 0 0.1 5 0. 8 0.7 8 2. 1 ma x 12,00 0 55. 6

- 29 0 55,40 0

1 0 15.2 35 0 0.3 2 1. 4 1. 2 2. 7 Populatio n

4 mi n 12,700 19 0

- 46 1 63,20 0

1 3 24. 1 40 0 0.4 2 1. 6 1. 6 3. 9 ma x 30,20 0 58 7

- 46 1 77,30 0

1 9 24. 1 45 0 0.6 0 1. 7 2. 0 3. 9

1 Aci d Generation Potential i n unit s o f ton s CaCO

, equivalent s pe r 100 0 ton s o f materia l

2 Catio n Exchang e Capacit y i n unit s o f milliequivalent s pe r 10 0 gram s

1 Neutralizatio n Potential i n unit s o f ton s CaCO
3 equivalent s pe r 100 0 ton s o f materia l

### TABL

E 5-2

. Majo r Constituent s (ing/kg)

, i n Slag an d Subsoil s wit h Value s Assigne d t o Concentratio n Rang e Populations

- a s indicate d b y Boxe s an d Shadin g { Populatio n 2 SAMPLE A

l C a O FcII I M

g M B (a s NO3 ) (a s NOZ ) S

I N a AVO101MO O AV0102MO O AVS101MO O AVS102MO O AVS103MO O AVS109MO O AVS104MO O AVS105MO O AVS106MO O AVS10BMO O AVS110MO O AVS112MO O AVS113MO O AVS116MO O AVS107MO O AVS111MO O AVS111MOO D AVS1HMO O AVS115MO O AVS11SMOO D 18,00

0 5.2 0 3.0 0 12 0 23 0 12 0 10 0 10 0 1.9 0 1.9 0 1.8 0 11 0 1.8 0 10 0 1.9 0 11 0 1.9 0 1.8 0 17 0 3.1 0 18 0Tabl e 5-2 , Pag e 2 o f 3 (a s N03 ) (a s NO2 )
1.8 0 14 0 12 0 16 0 10 0 SAMPL E HRO1Q5MO O HR0106MO O HRSIOIMO O HRSIOIMO O HRS103MO O HRS104MO O
LPCOLUMN l LFCOLUMN 2 LPOIOSMO O LPO106MO O LPS101MO O LPS102MO O LPS103MO O LPS104MO O
OOS101MO O LES101MO O MBS101MO O UES101MO O A

l

i 21,90 0 ! 78,10 0 i K S I N a ! 4,79 0 ! 123,00 0 \ 53 8 } S 5,09 0 S 121,00 0 S 88 4 {
i 4,74 0 ! 131,00 0 ! 87 7 i SO

4 384.0 0 <1.0 0 <1.0 0 } 5,09 0 S 121,00 0 S 88 4 { 293.0 0 I M i 4,74 0 ! 131,00 0 \ 87 7 J -» " 1________________ 5

,,____ _ .._._. «

- —-----_IM[*

. <1.0 0 i 4m n ! iran m 4,46 0 "I————————* ! 108,00 0

.+————- I <1.0 0 i 4,46 0 ! 123,00 0 |
<1.0 0 ! 5^3 0 ) 109,00 0

<1.0 0 <1.0 0 : : : ! : : : : ; : : A : : : : : : : : : : ; : ; : ; : : : : : : : ; : : : : x : :5: : : : : : W: : : : :S:ttv:v: : : : : : : : : : : : : : : : : : * : : : : : : : : : 57 7 l;;||||w|i^|l l

3,61 0 \ 137,00 0 S 23 2 Lm

mmmmmmmmm J 3,04 0 i 132,00 0 j i " <1.00 ! 5,62 0 {
<1.0 0

1 ^ 22^0 0 ! 68,90 0 jTabl e 5-2 , Page 3 o f 3 (a s NO3 ) (a s NO2 ) AVB101T1 4 AVB102T1 7 AVB103T14 5 AVB104T19 HRB101T1 0 HRB102T1 0 HRB103T2 3 LPB101T3 4 LFB1021305 LPB1Q3137 7 HSSIOIMO O HSS102MO O HSS103MO O HSS104MO O

### TABL

E 5-3

. Trac e Metal s (mg/kg)

, i n Slag an d Subsoil s wit h Value s Assigne d t o Concentratio n Rang e Populations

, a s Indicate d b y Boxe s an d Shadin g Populatio n 1 { Populatio n 2

AVO101MO O AVO102MO O AVS101MO O AVS102MO O AVS103MO O AV5109MO O AVS104MO O AVS105MO O AVS106MO O AVS10SMO O AVS110MO O AVS112MO O AVS113MO O AVS116MO O AVS107MO O AVS111MO O AVS111MOO D AVS114MO O AVS11SMO O AVS115MOO D J 44 0 ! • r r TM TM TM TMTM~

~

, 1Z.C W

, -1—————— H

I A A A I

I 1,53 0 ITabl e 5-3 , Pag e 2 o f 3 SAMPL E S b A a C o C o P b N l S e Z

n

t 4.2 0 45.1 0' "————" T 6.7 0 S 35.6 0

»m o i «*« w | o.r v | L 7.4 0 i 61.9 0 ! 1.3 0 j ^ ,. l r _ t _ m j
| 272.0 0 1 «*TM1MO O 272.0

0 SSiiSiiiiSiliiii-------

- LES101MO O j ^ 1 0 j 2350, , ! 235.0 0 I 1,41 0 MBSIOIMO O a* ) |

mo o 

# uEsioiMo o r"sir"te H HR0105MO O

. 577 0 HR0106MO O | »w~r~MJOO~T~i«"

~ HRS101MO O 7i9 0 ! 220.0 0 969* " HRS102MO O HRS103MO O HRS104MO O
LPOOLUMN 1 I 52^0"" ] LPGOLUMN 2 | """""" " LPO105MO O i LP0106MO O j

w w j LFS101MO O LPS102MO O LFS103MO O

H\UM\LBADI»T\IU.TAILB5 4

RBV OTabl e 5-3 , Pag e 3 o f 3

AVB101T1 4 AVB102T1 7 AVBKOTM S AVB1MT1 9 HRB101T1 0 HRB102T1 0 HRB103TI73 LPB101T3 4 LPB10CT37 7 HSS101MO O ! HSS102MO O HSS103MO O HSS104MO O

ra\UM\UADIVr\IU-TABLB5 4

RH V 0

### TABL

E 5-4

. Miscellaneou s Measurement s i n Sla g an d Subsoil s wit h Value s Assigne d t o Populations

, a s indicate d b y Boxe s an d Shadin g MMHWMWWV

— — —v.......................................,................. ^ Populatio n 1 { PopuHUon Z SAMPL E AGP

1 CaEX * N P

1 NEx/S

4 Py/S * S< V S * Tota l S T AVO101MO O AVO102MO O AVS101MO O AVS1Q2MO O AVS109MO O AVS109MO O AVS104MO O AVS1QSMO O AVS106MO O AVS108MO O AVS110MO O AVS112MO O AVS113MO O AVS116MO O AVS107MO O AVStllMO O AVS111MOO D AVS114MO O AVS11SMO O AVS115MOO O 220

1.9 0 15

0 f r — • 1 1

- j i 

# I 1 

# ! l.U

I
2.0 0 IM
05 0 0.4 0 0.9 0 1.0 0 0.4 0 ——— —

____

——— —

——— —

...
0.9 0 0.8 0 

# 13 0 r QSO ISO ! 1.4 0 1.6 7Tabl e 5-4 , Pag e 2 o f 3 SAMPL E AGP * CaEX

* N P * NEx/S 4 Py/S

5 SO«/S * Tota l S 7 HRO1QSMO O HRO106MO O HRS101MO O HRS102MO O HRS103MO O HRS104MO O
LPCOLUMN 1 LPCOLUMN 2 LP010SMO O LPO106MO O LFS101MO O LPS102MO O LPS103MO O LPS104MO O
OOS101MO O LES101MO O MES101MO O UES101MO O <OJ

O

<OJ O 1.0 2



## ._ _ I

0.6 5 ] |j mMmMMMma ^ M

J <0.0 1 I 0.6 0 (._____—_.

. iiiiiriiriiii'iiiriiia'ffiif c '^jiiiiiiii't'i iii'i'i iri'i^iM.'iikiai'iii » 0.6 5 I 1.0

0 1.1 9

M\im\UMIHVIMU-TABLB54

.

RB V «Tabl e 5-4 , Pag e 3 o f 3

AVB101T1 4 AVB102T1 7 AVBKOTU S AVBUMT1 9 HRB101T1 0 HRD102T1 0 HRB107T2 3 LPB101T3 4 LPB1Q2TM 5 LPBUBTI37 7 HSS101MO O HSS102MO O HSS103MO O HSS104MO O

1 Aci d Generatio n Potentia l (ton s o f CaCO

, equivalent s pe r 100 0 ton s material ) 1 Catio n Exchang e Capacit y (milliequtvalent s pe r 10 0 grams ) 3 Neutralizatio n Potential (ton s o f CaCO

, equivalent s pe r 100 0 ton s material ) 4 Non-Extractabl c Sulfu r (% ) •yiia i nri » • «r»^>ni n Neutralizatio n roienua i ^10 1 4 Non-Extractabl c Sulfu r (% ) 5 Pyriti c Sulfur (% ) * Sulfatc(% ) 7 Tota l Sulfu r

•B\im\LEADIVniU-TABLa5-4

.

RE V 0

### contai

n fou r populations

. I n thes e cases , population s wer e assigne d base d upo n th e numbe r
o f discernabl e group s o f data

. 

### Compariso n o f the majo r element s show s difference s between the zin c sla g an d the othe r sla g sampl e dat a set s (Tabl e 5-2)

. Th e difference s betwee n sla g fro m th e differen t pile s i s illustrate d b y th e aluminum
, calcium
, iron , sulfate

, and manganes e concentrations

. Th e zin c dat a se t i s generall y highe r i n manganese an d sulfat e an d lowe r i n iron , aluminu m an d 

### calciu m whe n compare d t o th e dat a set s a s a whole

. Th e concentration s o f trac e metal s ar e generall y variabl e throughou t th e sla g pile s (Tabl e 5-3)

. Th e Wester n Zinc dat a se t i s lo w 

### i n lea d an d hig h i n zin c an d cadmiu m whe n contraste d wit h th e other sla g samples

. I n summary , the Wester n Zin c sample s ar e highe r i n manganese , sulfate

, zin c an d cadmium
, an d lower i n lead
, aluminum
, iro n an d calciu m whe n compare d t o al l sla g data

. 5.1. 4 Statistica l Summar y Informatio n fro m whic h th e abov e discussion s and conclusion s wer e derive d ar e presente d i n Appendi x C o f thi s report

. Th e lo g normalit y o f th e dat a i s verifie d throug h th e examinatio n o f histograms

. Th e statistica l result s sho w that th e Wester n Zin c sla g pil e differ s i n certai n element s fro m th e sla g dat a se t a s a whole

. 5. 2 Potentia l fo r Wate r Qualit y Impact s Tes t result s showe d tha t th e tendenc y fo r zin c sla g t o leac h metal s t o aqueou s solution s i s minimal
, a s al l eluat e concentration s wer e wel l belo w toxi c characteristic criteri a fo r the primar y metal s o f concern
. However

, a s wit h al l metals-containin g environmenta l media
, 

### som e leachin g doe s occur
. Calculation s wer e performe d t o determin e th e potentia l metal s loa d fro m the zin c sla g pile
, base d o n the result s o f the SPL P an d colum n leac h tests

. Dat a fro m th e othe r PR P RI effort s ma y b e use d t o refin e assumption s use d i n thes e loadin g 

### calculation s an d t o evaluat e whethe r th e potentia l loading s represen t a significan t environmental impact

. Calculation s wer e performe d for thre e o f th e primar y element s o f concer n - - lead
, cadmiu m 

### an d zinc

. Loadin g calculation s fo r arsenic , th e fourt h primar y elemen t o f concern , wer e no t 

### performe d becaus e o f the significan t numbe r o f non-detec t result s i n the analytica l data

. 

### I n the subsectio n 5.2.3 , the SPL P and colum n leac h loadin g estimate s hav e bee n combine d t o develo p a bes t estimat e base d o n th e result s o f bot h test s an d site-specifi c information

. Th e assumptions an d calculatio n method s used
, a tabulatio n o f results
, an d a discussio n
MORRISO N KNUOSE N CORPORATIO N BB\1883\ZINCRPT\Rnal-R I

5~ 5 [Re v 001/13/93 ]

### concernin

g the potentia l fo r wate r qualit y impact s ar e presente d below

. Appendi x D 2 contain s th e calculatio n sheet s and supportin g documentation

. Summarie s o f th e leachin g 

### tes t methodologies
, a s wel l a s th e result s o f th e actua l tests , wer e presente d earlie r i n thi s report

. 52.1 Metal s Loadin g Base d on SPL P Result s 

### The SPL P tes t (Metho d 1312 ) wa s designe d t o determin e th e mobilit y o f metal s b y 

### simulatin g th e effec t o f hig h countr y precipitatio n percolatin g throug h a min e wast e pile

. Result s o f th e procedur e simulat e th e buffered

, oxygen-deplete d condition s i n th e ulterio r o f the piles

. Annua l metal s loadin g fro m the zin c sla g pil e (mas s pe r year ) wa s estimate d b y multiplyin g the SPL P eluat e concentratio n (i n ug/1 ) b y the numbe r o f liter s o f precipitatio n contactin g the zin c sla g pil e i n one year
. The followin g assumption s hav e bee n use d t o estimat e annua l loading :

• Th e annua l precipitatio n fo r Leadvill e i s 12.6 7 inche s pe r yea r (Res-ASARCO

, 1991 )

• Al l precipitatio n infiltrate s th e pile ; runo n an d runof f wer e considere d t o balanc e
ou t an d evaporation/sublimatio n

wa s no t considere d N o groun d wate r flow s int o th e pile s t o interact wit h percolatin g wate r Precipitatio n percolate s throug h th e pile
, achievin g a metal s concentratio n represente d b y th e eluat e chemica l concentrations , and exit s th e pil e t o th e Californi a Gulch hydrologi c syste m



### • The metal s concentration s ar e geometri c mean s o f th e SPL P dat a Pil e surfac e are a i s assume d t o b e th e 'footprint * o f th e pile
, calculate d fro m th e pla n vie w (Figur e 4-1 ) a s 201,00 0 squar e feet

, an d i s use d fo r precipitatio n volum e calculation s 

### T h e result s o f th e zin c sla g pil e loadin g calculation s fro m SPL P concentration s fo r lead
, cadmium
, an d zin c ar e estimate d a t 0.1 , 0.01 , an d 0. 4 kilogram s pe r year , respectively

. The SPL P test s ar e considere d t o overestimat e the actua l mas s leache d under oxygen
deficien t condition s fo r th e reason s give n below : MORfflSO N KNUDSEN CORPORATIO N BB\1883\ZINCRPT\Rnal-R I

5" 6 [Re v 001/13/93 ]Th e

lixiviant contain s non e o f th e carbonat e buffe r i n natura l rainfall

. Th e absenc e
o f carbonat e bufferin g capacit y ma y intensif y leaching
, especiall y i n case s wher e the 

### dominan t minera l species ar e carbonat e o r sulfid e based

. Th e sample s ar e tumble d durin g th e test , allowin g th e sampl e materia l t o constantl y impac t an d grin d together
, potentiall y generatin g fres h surface s fo r th e lixiviant t o contact

. Thi s doe s not occu r under the relativel y static condition s o f a sla g pile

. 52 2 Metal s Loadin g Base d o n Colum n Leac h Result s A colum n leac h tes t wa s performe d o n a zin c sla g sampl e i n orde r t o simulat e hig h countr y precipitatio n percolatin g throug h th e sla g pil e unde r unsaturate d conditions

. Result s o f thi s tes t represen t the situatio n at the surfac e o f the pile

. Annua l metal s loadin g fro m the zin c sla g pil e (mas s per year ) wa s estimate d b y scalin g th e tota l mas s o f leache d meta l o f concer n fro m colum n leac h testin g (i n ug ) t o the tota l mas s o f the sla g pil e and the numbe r o f year s
o f precipitatio n represente d b y th e test

. Th e followin g assumptions , i n additio n t o thos e 

### state d i n th e SPL P sectio n above
, hav e bee n use d t o estimat e annua l metal s loading : Mas s o f meta l leache d fro m colum n leac h test s



### • mas s leache d equale d integratio n b y trapezoida l rul e o f th e eluat e 

### concentration s fro m even t 0 t o even t 10 0 (i.e.

, th e are a under th e curve ) • even t 0 leache d 0. 0 ug/ 1 • fo r value s reporte d a s belo w detectio n limit
, one-hal f o f th e detectio n limi t


### wa s use d Mas s o f sla g pil e



### • mas s wa s calculate d base d o n measure d pil e volumes
, specifi c gravit y an d estimate d porosit y • volum e o f th e sla g pil e wa s take n fro m Figur e 4- 1 a s 35,000 cubi c yard s • specifi c gravit y o f th e sla g (3.25 ) wa s equa l t o tha t o f th e < 1 0 mes h fractio n • sla g pil e porosit y wa s conservativel y estimate d a t 25 %

MORRISO N KNUOSE N CORPORATIO N BB\1883\ZlNCRFT\Flnal-R l

5- 7 [Re v 001/13/93 )

### Th e result s o f th e zin c sla g pil e loadin g calculation s base d o n colum n leac h tes t eluat e concentration s fo r lead
, cadmiu m an d zin c ar e estimate d a t 0.6 , 2 , an d 38 0 kilogram s pe r 

### year , respectively

. 

### Th e colum n leac h test s ar e mor e aggressiv e tha n actua l sit e condition s for severa l reasons : Th e IMvian t contain s non e o f th e carbonat e buffe r i n natura l rainfall

. Th e absenc e o f carbonat e bufferin g capacit y wil l likel y intensif y leaching
, especiall y wher e th e dominan t minera l specie s i s carbonat e o r sulfid e based

. Th e sulfuri c acid/nitri c aci d base d lixiviant i s mor e aggressiv e tha n a carboni c 

### acid-base d lixiviant tha t woul d b e mor e simila r t o natura l rainfall

. Th e effec t o f we t an d dr y cyclin g durin g testin g simulates th e reaeratio n perio d that likel y occur s nea r th e surfac e o f th e sla g pil e betwee n precipitatio n event s whe n sno w cove r i s no t present

. I f thes e result s wer e extrapolate d t o th e sla g pil e a t depth
, loadin g calculation s woul d b e overl y aggressiv e becaus e reaeratio n o f th e materia l i n th e interio r o f th e pil e woul d



### no t likel y occu r unde r sit e conditions

. Additionally

, i n th e natura l setting , a
muc h longe r dryin g o r aeratio n perio d i s expecte d rathe r tha n equivalent period s o f wet and dry

. Thes e longe r dr y cycle s ar e expecte d t o facilitat e reformatio n o f oxidatio n rind s o n the particles

. The colum n leac h testin g performe d ca n als o b e considere d aggressiv e sinc e 

### result s indicate d tha t th e sla g pile s hav e no t reache d steady-stat e leachin g condition s i n Leadville

, a s woul d b e assume d fro m th e numbe r o f year s exposur e t o atmospheri c conditions

. Th e depletio n o f bicarbonat e an d sulfat e
and increasin g trend s i n leache d metal s concentration s durin g testin g indicate d tha t steady-stat e conditions
, a s the y likel y exis t i n Leadville

, wer e no t completel y simulated

. I f colum n condition s wer e simila r t o expecte d i n sit u 

### conditions
, th e anion s woul d no t sho w a depletio n effec t o r th e metal s a n increasin g trend

. 5.2. 3 Metal s Loadin g Base d o n Combinatio n o f SPL P an d Colum n Leac h Result s 

### Base d o n th e abov e discussion
, th e us e o f a combinatio n o f SPL P an d colum n leac h result s woul d provid e th e bes t estimat e o f th e annua l metal s loa d leache d fro m th e zin c sla g pile

. 

### Th e colum n leac h result s wer e use d t o estimat e th e leachin g tha t occur s i n th e are a o f th e
MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Final-R I

5" 8 [Re v 001/13/93 ]

### sla g pil e wher e reoxygenatio n o f th e sla g i s likel y t o occu r eithe r b y exposur e t o atmospheri c oxygen or oxygenate d water

. Fou r feet

, a distanc e tha t i s slightl y greate r tha n tw o time s th e lengt h o f th e column s used
, ha s bee n assume d t o represen t thi s zone
. Th e us e o f thi s distanc e i s furthe r justifie d b y the observatio n tha t the colum n leac h eluat e p H approache d th e SPL P fina l p H afte r percolatio n throug h th e columns

. Th e SPL P result s hav e bee n use d t o estimat e th e quantit y o f metal s that coul d b e leache d fro m an y par t o f a sla g pil e a t depth s greate r tha n fou r fee t wher e th e environmen t i s oxygen-deficient

. Th e amoun t o f a give n pil e greate r tha n o r les s tha n fou r fee t thic k wa s estimate d fro m th e averag e thickness
, determine d b y dividin g th e pil e volum e b y th e pla n vie w surfac e area
. Usin g th e 

### combinatio n o f SPL P an d colum n leac h results
, th e resultin g estimate d metal s load fro m th e zin c sla g pil e fo r lead
, cadmiu m an d zin c i s 0.5,1. 6 an d 33 0 kilogram s pe r year , respectively

. Thes e loadin g estimate d ma y b e refine d a s additiona l informatio n become s available

. 5. 3 Potentia l fo r Soil Impact s The result s o f the reconnaissanc e o f the zin c sla g pil e showe d no significan t impac t t o surfac e soil s i n th e vicinit y o f th e pile

. N o evidenc e o f particulat e movemen t of f th e pile s
wa s note d i n th e field

. I n addition
, ai r pathwa y analysi s di d no t indicat e th e potentia l fo r windblow n fine s t o impac t soils

. Subsla g materia l wa s not sample d a t the zin c sla g pile

. 5. 4 Sla g Pil e Stabilit y 

### Th e structura l (geotechnical ) stabilit y o f th e zin c sla g pil e wa s evaluate d durin g th e fiel d 

### reconnaissanc e task

. Th e pil e i s generall y low
, wit h onl y a smal l are a o f significan t heigh t (approximatel y 1 5 feet)

, an d exhibit s n o sign s o f significan t fracturing

. Therefore

, th e pil e present s n o stabilit y concern
. Becaus e o f th e vesicula r natur e o f th e zin c slag
, freeze/tha w cyclin g ma y hav e som e impac t

o n zin c slag

. Som e disintegratio n o f th e sla g ma y b e occurrin g du e t o pressur e exerte d b y 

### freezin g wate r i n th e sla g vugs

. However

, a s there doe s no t appea r t o b e significan t runof f fro m th e pil e o r win d erosion , an y disintegratio n does no t appea r t o hav e a n impac t o n th e environment

. 5. 5 Potentia l fo r Ai r Qualit y Impact s Analysi s o f emission s calculations usin g th e 199 1 meteorologica l dat a fro m th e Colorad o Mountai n Colleg e (Res-ASARCO

, 199 la ) an d th e mod e o f th e aggregat e siz e distributio n hav e demonstrate d that win d erosio n doe s no t occu r fro m th e Wester n Zin c sla g pile

. Thi s conclusio n wa s reache d b y followin g industry-standar d

procedures an d guidanc e fro m th e MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Final-R 1

5- 9 [Re v 001/13/83 ]EP

A regiona l offic e i n Denver

, Colorad o (EPA

, 1992)

. Th e procedures
, describe d i n Sectio n 3.4.2 , wer e use d t o determin e th e frictio n velocit y (win d spee d a t th e pil e surface )



### an d th e threshol d frictio n velocit y (minimu m win d spee d a t whic h particle s wil l becom e airborne)

. Th e frictio n velocit y o f 0.5 5 m/se c wa s then compare d t o th e threshol d frictio n 

### velocit y fo r th e zin c sla g (1. 0 m/sec)

. A frictio n velocit y lowe r tha n th e threshold
, show s tha t Leadvill e win d speed s are no t fas t enoug h t o caus e win d erosio n fro m th e pile

. Th e result s ca n b e furthe r explaine d b y examinin g th e factor s involved i n emission s 

### potential

. The smal l sil t an d cla y siz e fractions

, define d a s the amoun t o f materia l tha t passes throug h a 200-mes h sieve , hav e th e greates t potentia l for erosion

. I n th e Wester n Zin c pile
, thi s fractio n i s les s tha n 6 percent

. This

, alon g wit h th e moderat e maximu m hourl y averag e win d spee d i n Leadville

, limit s the fines abilit y t o becom e airborne

. A n additiona l facto r tha t wa s no t include d i n th e calculations
, bu t woul d furthe r limi t credibilit y i s th e extende d period s o f sno w cove r i n Leadville

. Period s o f hig h moistur e an d winter sno w cove r woul d suppres s an y potentia l fo r fugitiv e dus t emissions

. Climatologica l observation s fro m th e Leadvill e airpor t indicat e tha t ther e i s a persisten t sno w cove r fro m Novembe r throug h April

. I n addition
, Jul y an d Augus t ar e typicall y month s o f hig h precipitatio n (Res-ASARCO

, 19 9 la)

. Th e emission s calculations d o no t tak e int o accoun t

an y conditions othe r tha n thos e idea l fo r win d erosio n o f material

. 5. 6 Anthropogeni c

Distributio n Distributio n o f th e zin c sla g ha s no t bee n documented ; however
, a significan t volum e decreas e ha s occurre d ove r th e las t severa l decades

. Sit e reconnaissanc e showe d wha t appear s t o b e material fro m the Wester n Zinc pil e o n roadway s an d roa d shoulder s withi n th e site

. Zin c sla g ha s no t bee n use d b y railroad s i n th e Leadvill e area
.

MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRPT\Final- «

5-1 0 [Re v 001/13/93 )6 . 0

SUMMAR Y AN D CONCLUSION

S Thi s sectio n summarize s th e finding s o f th e Zinc Sla g Pil e Remedia l Investigatio n base d o n th e dat a collecte d an d evaluate d t o date

. Eac h o f thes e result s hav e bee n describe d i n greate r detai l earlie r i n th e RI

. 6. 1 Summar y o f Zin c Sla g Characteristic s The result s o f the fiel d reconnaissance, physica l testing , and analytica l testing , a s wel l a s impact s t o water, soil
, an d ai r ar e summarize d below

. Physical Characteristic s 

### Zin c sla g i s a highl y vesicula r materia l consistin g o f mostl y coars e particl e sizes

. Th e fractio n o f zin c sla g passin g th e 200-mes h siev e i s les s tha n 6 percent

. Fo r th e fin e fraction

, approximatel y 7 percen t o f th e materia l i s < 10 0 /x m an d on e percen t i s < 10/xm

. Th e zin c sla g pil e i s generall y low
, wit h onl y a smal l are a o f significan t heigh t (approximatel y 1 5 feet)

. Th e zin c sla g pil e does no t presen t a stabilit y concern
. 

### Becaus e o f th e vesicula r natur e o f th e zin c slag
, freeze/tha w cyclin g ma y hav e som e impac t

o n zin c slag

. However

, a s ther e doe s no t appea r t o b e significan t runof f fro m th e pil e o r win d erosion , an y disintegratio n doe s no t appea r t o hav e a n impac t o n th e environment

. Chemica l Characteristic s Iro n an d silico n compos e th e majorit y o f th e zin c sla g materia l rangin g u p t o 20 % an d 15 % respectively

. Th e geometri c mea n concentration s o f th e primar y metal s o f concer n are a s follows :

• Lead-56 8 mg/k g •Cadmium

— 14. 1 mgk g •Arsenic-21 1 mg/k g •Zinc-66,00 0 mg/k g 

### Th e minera l specie s wit h whic h thes e metal s ar e boun d (e.g.

, oxide
, sulfide

, sulfate ) wil l b e determine d b y othe r investigator s an d reporte d i n forthcomin g metal s speciatio n reports

.

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Flnal- «

6- 1 [Re v 001/13/93 ]Th e

dominan t for m o f sulfu r i s sulfat e sulfur

. Aci d generatio n potentia l du e t o pyriti c sulfur

, whe n detected
, i s mor e tha n compensate d b y neutralizatio n potentia l du e t o carbonat e species

. Thi s result s i n a negativ e aci d formin g potential

. 

### T h e Syntheti c Precipitatio n Leachin g Procedur e (SPLP ) result s fo r al l element s fo r al l sample s wer e belo w th e toxicit y characteristi c criteri a liste d i n 4 0 CF R 261.2 4 o f 10 0 time s 

### primar y drinkin g wate r standards

. Mea n value s wer e generall y mor e than tw o order s o f magnitud e lowe r tha n toxicit y criteria

. Additionally

, result s fo r thos e analyte s tha t wer e compared t o criteri a o f 10 0 time s th e secondar y drinkin g wate r qualit y standard s wer e lowe r tha n thos e criteria

. Statistica l Analyse s Th e result s o f th e statistica l analyse s indicat e tha t th e constituent s withi n th e zin c sla g sample s ar e log-normall y distributed

. Comparison s o f th e zin c sla g dat a wit h lea d sla g dat a set s sho w tha t th e zin c sla g pil e i s lowe r i n lea d an d iro n an d highe r i n zin c an d manganes e tha n th e lea d slag

. Wate r Qualit y Impact s Base d o n th e metal s concentration s i n th e eluant s o f th e tw o type s o f leachin g test s performe d o n zin c sla g sample s (SPL P an d colum n leach)

, potentia l annua l metal s loadin g 

### fro m th e zin c sla g pil e ha s bee n estimated

. Calculation s wer e performe d fo r thre e o f th e primar y element s o f concer n — lead
, cadmium an d zinc

. Arseni c meta l loadin g wa s no t calculate d becaus e o f non-detectabl e arseni c concentration s fo r th e majorit y o f th e leachat e samples

. 

### Usin g th e combinatio n o f SPL P an d th e zin c colum n leac h results
, th e metal s loa d fo r th e zin c sla g pil e fo r lead
, cadmiu m an d zin c i s conservativel y estimate d a t 0.5 , 1. 6 an d 33 0 kilogram s pe r year , respectively

. Thes e loadin g estimate s ma y b e refine d a s additiona l informatio n become s available

. 

### Soi l Qualit y Impact s Result s o f the reconnaissanc e o f the zin c sla g pil e showe d n o obviou s impact s t o surfac e soil s i n th e vicinit y o f th e pile

. N o evidenc e o f particulat e movemen t of f th e pil e wa s noted

.

MORRISO N KNUDSEN CORPORATIO N BB\1893\ZINCRPT\Final-R I

6" 2 [Re v 001/13/93 ]A i

r Qualit y Impact s Emission s calculation s demonstrat e tha t win d erosio n does not occu r fro m the zin c sla g pil e
an d i t ca n b e conclude d tha t ther e ar e n o significan t impact s fro m th e zin c sla g pil e durin g undisturbe d conditions

. 6 2 Conclusion s Regardin g th e Sit e Conceptua l Mode l 

### Th e sit e conceptua l mode l for th e Sla g Pil e RI (Figur e 1-2 ) wa s develope d b y EP A an d th e Ris k Assessmen t Technica l Assistanc e Committe e and presente d i n the wor k pla n fo r the Sla g Pil e R I (MK

, 1991a)

. Th e conceptua l mode l present s fiv e potentia l releas e mechanism s fo r th e sla g piles

. Thes e are :

- win d

- leachin g

- mixin g b y huma n activitie s

- runof f (o f particulat e slag )



### - direc t contac t I f certai n releas e mechanism s ca n b e show n no t t o occur , the n secondar y sources , exposur e route s an d potentia l receptor s d o no t for m a complet e pathway

. Th e followin g discussio n applie s th e conclusion s o f th e RI activitie s t o eac h o f th e primar y releas e mechanism s i n orde r t o sho w whethe r the conceptua l mode l i s vali d fo r that particula r mechanism

. Eac h 

### releas e mechanism i s addresse d i n th e orde r presente d above

. Releas e Mechanis m 1 - Win d Win d erosion , o r deflatio n o f th e zin c sla g pil e b y wind
, i s addresse d i n Section s 4.4. 2 an d 5. 5 o f thi s report

. Hourl y averag e win d spee d dat a multiplie d b y th e appropriat e facto r t o determin e th e maximu m sustaine d win d gus t doe s no t mee t o r excee d th e frictiona l velocit y necessar y t o lif t particle s of f th e stationar y pile

. Therefore

, th e air pathwa y analysi s result s sho w that win d erosio n i s no t a viabl e releas e mechanism for th e zin c sla g pile

. Releas e Mechanis m 2 - Leachin g Leachin g o f element s o f concer n wer e teste d b y tw o differen t leachin g procedure s (SPL P

and colum n leach)

, yieldin g the quantitie s o f metal s leache d fro m a give n mas s o r volum e 

### o f the zin c sla g pile

. Quantit y o f metal s leache d wer e calculate d b y portionin g the pil e b y whethe r i t coul d mos t likel y b e represente d b y colum n leac h o r SPL P testin g results

. The zin c sla g pil e ha s th e potentia l t o contribut e a smal l metal s loa d o f thre e o f th e element s
MORRISO N KNUDSEN CORPORATIO N B8\1883\ZINCRPT\Rnal-R I

6~ 3 [Re v 001/13/83 ]o f concern
. However

, th e concentratio n o f zinc , lead
, an d cadmiu m ar e al l belo w leachin g 

### criteri a establishe d b y EP A o f 10 0 time s drinkin g wate r standards

. Additiona l dat a collectio n activitie s ar e currentl y bein g undertake n unde r othe r PR P wor k plan s t o bette r defin e th e hydrologi c syste m i n th e vicinit y o f th e majo r sla g pile s an d alon g 

### Californi a Gulch

. Ke y additiona l dat a t o b e evaluate d includ e the portion s o f the Gulc h tha t ar e gainin g and losin g streams , wate r qualit y dat a fro m piezometers , monito r well s and surfac e wate r sampling
, an d flo w rate s durin g the cours e o f the year
. Anothe r consideratio n i s the calculatio n o f the residua l sedimen t loa d and the contributio n fro m othe r source s (i.e

. tailing s an d soils ) t o th e strea m channel

. A t thi s time , th e evaluation s o f impact s fro m leachin g hav e bee n conservativel y calculated

. Additiona l consideration s suc h a s soi l sorption , evaporation , dilutio n b y groun d an d surfac e water, an d shee t runof f o f precipitatio n 

### wil l nee d t o b e furthe r evaluate d befor e estimate s o f contributio n t o th e hydrologi c syste m
ca n b e completed

. A t thi s time , leachin g a s a releas e mechanis m i s retained

. Releas e Mechanis m 3 - Mixin g b y Huma n Activitie s Distributio n o f zin c sla g b y huma n activit y ha s no t bee n documented ; however
, volume decrease s an d evidenc e o f th e materia l o n Leadvill e roadway s indicat e use

. 

### Releas e Mechanis m 4-Runof f o f Sla g N o evidenc e o f transpor t o f sla g fine s b y surfac e runof f wa s observed a t th e zin c pile

. Sla g doe s no t appea r t o ru n of f pile s ont o adjacen t soil s i n rivulet s o r channels

. Thi s primar y releas e mechanis m fo r sla g shoul d b e eliminate d a s a concer n a t th e site

. Releas e Mechanis m 5-Direc t Contac t Direc t contact wit h th e sla g pile s wa s considere d insignifican t i n EPA' s Preliminary Baseline 

### Human Health Risk Assessment (EPA

, 1991a)

. Therefore

, i t ca n b e eliminate d a s a releas e mechanism

. 

### Summar y o f Verificatio n o f th e Conceptua l Mode l O f the fiv e primar y releas e mechanism s identifie d i n the sit e conceptua l model
, onl y one 

### ca n b e considere d viabl e base d on finding s provide d i n thi s Zin c Sla g Pil e Remedia l Investigation

. Th e on e retaine d releas e mechanism i s leaching

. Befor e determinin g th e actua l contributio n o f leache d constituent s fro m th e zin c sla g pile
, an d thei r potentia l environmenta l significance

, collatio n an d summarizatio n o f dat a collecte d a s par t o f othe r

MORRISO N KNUDSE N CORPORATIO N BB\1893\ZINCRPT\Flnal-R I

6- 4 [Re v 0 01/13/93 ]wor

k program s wil l nee d t o b e evaluated

. Al l othe r primar y mechanism s hav e bee n eliminate d a s a resul t o f thi s remedia l investigation

.

MORRISO N KNUDSE N CORPORATIO N BB\1883\ZINCRFT\Final-R I

6- 5

[Re v 0 01/13/93 ]7. 0

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. ASTM

, 1992a

. Standard Method fo r Particle Size Analysis o f Soils, Designatio n D-422-6 3 (Reapprove d 1990)

, Annua l Boo k o f AST M Standards

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. ASTM

, 1992b

. Standard Practice fo r Sampling Aggregates, Designation : D-75-87

, Annua l Boo k o f AST M Standards

, 1992

. Blair

, 1980

. Leadville: Colorado's Magic City b y Edwar d Blair

, Pruet t Publishin g Company

, Boulder

, Colorado

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, 1978

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- A Systematic Analysis o f Late Cenozoic Landforms, b y Arthu r L

. Bloom

, Prentice-Hall

, Inc.

, Englewoo d Cliffs

, Ne w Jersey

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. Burea u o f Mines

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