# Apach e Tailin g Impoundment s Operabl e Unit 7 Propose d Pla n 

# Publi c Meetin g Januar y 25 , 200 0 PRESENTATIO N PACKE T Prepare d by : Asarc o Incorporate d 13 0 Wes t 9 t h 

### Stree t 49 5

Eas t 51 s t 

### Ave

. Leadville

, C O 8046 1 Denver

,

C O 8021 6

M 

# ASAfiC O

consultin g scientist s an d engineer s

# Colo r

Ma p T h e followin g ma p contain s colo r tha t does no t appea r o n scanne d image

.• Denve r Georgetow n

DENVE R AN D RI O GRANO E WESTER N

CANTERBUR Y TUNNE L J
LEADVILL E DRAINAG E TUNNE L Even s Gulc h

Stra y Hors e Gulc h Stor r Ditc h 

### OU7-APACJ^ E TAILING S Y / K TUNNE L

CALIFORNI A GULC H CALIFORNI

A GULC H

. SUPERFUN D SIT E BOUNDAR Y N

ASARC O O U 7 - APACH

E TAILING

S FIGUR E 1- 1 

### GENERAL SIT E LOCATIO N MA P PROJECT : 5344. 4 DATE :

SEPTEMBE R 199 9 B Y : SCG I CHECKED : DL L MFC

, Inc

. consulting scientists and engineers

# RI/F S PROCES S FO R OPERABL E UNI T 7
Superfun d Listin g 

### 198 3 

### Site-Wid e Remedia l 

### Investigation s (Rl ) 1991-199 3 Consen t Decre e 

### 199 4 i 

### Draf t Feasibilit y Stud y 199 6 

### Supplementa l Investigatio n & Evaluation

, Interi m R l & F S Submittal s 1997-199 9 Remova l Action s 199 7 & 1999


### Fina l Focuse d Feasibilit y Stud y 200 0 

### Propose d Plan/Publi c Commen t 200 0 

### Recor d o f Decisio n (ROD ) 200 0 

### Remedia l Actio n 2000-200 1 

# ASAfiC O

# Sit e Descriptio n Tailing Impoundment s

• Fou r distinc t tailin g impoundment s • Mai n Impoundment : 

# 11. 3 acre s

- 630,00 0 c y maximu m thicknes s o f 5 0 f t • Nort h Impoundment : 

# 1. 8 acre s

- 14,50 0 c y maximu m thicknes s o f 12. 5 f t 

# • Tailin g Pond s 2 an d 3 : 2. 0 acre s tota l

- 41,200c y



# - 6 t o 1 4 f t thic k ASARC

O

# Sit e Descriptio n (cont. ) Surfac e Wate r • Californi a Gulch channe l belo w Mai n Impoundmen t tailin g vi a two 24-inc h clay



# til e culvert s • Woode n bo x culver t drain s upgradien t 

# surfac e wate r 

# • Star r Ditc h convey s runof f fro m Stra y Hors e Gulch an d eas t Leadvill e 

# Groundwate r • Pore wate r withi n tailin g • Alluvia l aquife r - i n unconsolidate d 

# sedimentar y deposit s beneat h impoundment s 

# • Bedroc k aquife r - i n consolidate d bedroc k • Numerous spring s i n are a 

# ASAfiC O

# Colo r

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PAVE O ROA D GRAVE L ROA D WATE R BUUHNG/STRUCTUR E POUE R POL E EXPLANATIO N SURFAC E WATE R SAUPt l LOCATIO N CKOUNOWATE R UOMTOR1N C 1KU. SOn.BO«N G UINI-REZOUETE R PIEZOUETER LOCATIO N ASARC O O U 7 - APACH E TAILING

S SIT E MA P OPERABL E UNI T 7 APACH E TAILING S IMPOUNDMEN T PROJECT : 5344. 4 REV : DATE :

JANUAR Y 200 0 B Y : JMK | CHECKED : MFC

, Inc

. consulting scientists and engineers

# Summary o f Remedia l 

# Investigation s Objectiv e - evaluat e th e natur e an d exten t o f contaminatio n 

# Characterizatio n o f sources , groundwater

, an d surfac e wate r 1 

# Activities : 

# groundwate r sampling/analysi s 

# groundwate r leve l monitorin g geotechnica l testin g surfac e wate r sampling/analysi s 

# geochemica l testing/analysi s pon d wate r sampling/analysi s 

# rainfall-runof f sampling/analysi s 1 

# Surfac e wate r and groundwate r mas s loadin g analyses t o identif y source s 

# ASARCO

# R I Summar y Mai n Impoundmen t (MI) : acid-generatin g a t an d nea r surfac e acid-neutralizin g a t base 

# Nort h Impoundmen t (NI) : highl y acid-generatin g tailin g hig h infiltratio n 

# Tailin g Pond s Nos

. 2 an d 3 (TP2/3 ) highl y acid-generatin g tailin g


# remove d i n 199 7 

# Groundwate r loadin g mechanisms : runof f fro m M I embankment s percolatio n throug h TP2/ 3 percolatio n throug h N I tailin g 

# ASARCO

# R I Summar y Surfac e Wate r • Flow/load s var y seasonall y an d yearl y 

# • Load s predominantl y fro m upstrea m inflow s 

# • Loadin g fro m spring s downgradien t o f TP2/ 3 

# decrease d substantiall y afte r tailin g remova l i n 199 7 

# ASflfiC O

# Remova l Action s 

# 1997-199 9 199 7 

# • Remove d Tailin g Pond Nos

. 2 and 3 

# • Backfilled/regrade d

excavatio n area s • Regrade d unstabl e are a an d place d



# roc k protectio n alon g to e o f S W slop e o f Mai n Impoundmen t 199 9 • Regrading/placemen t

o f pre-loa d fil l



# on souther n portio n o f Mai n Impoundmen t 

# • Installe d wic k drain s i n pre-loa d fil l

are a 

# • Place d fil l ove r Nort h Impoundmen t 

# ASARCO

# Remedia l Actio n O b j ective s Contro l airborn e transpor t o f tailin g particle s 

# Contro l erosion o f tailin g material s an d depositio n int o 

# loca l wate r course s Contro l leachin g an d migratio n o f metal s fro m tailin g int o 

# surfac e wate r Contro l leachin g and migratio n o f metal s fro m tailin g int o groundwate r 

# ASARCO

# Cultura l Resource s Consideration s T w o resource s (sites ) evaluated : Apach e Mill/Tailin g Pil e 

# Possibl e stam p mil l Mill/tailin g ineligibl e an d non



# contributin g 

# Stam p mil l i s potentiall y eligibl e fo r nominatio n t o th e NHRP

, bu t i s no t 

# contributin g a s a landscap e featur e Dat a recover y pla n submitte d t o 

# SHP O Implemen t Dat a Recover y Pla n and 

# perfor m mitigation , i f necessary , prio r t o disturbanc e 

# ASARCO

# Remedia l Actio n Alternative s

• #1 : N o Actio n
• #2A : Simpl e Soi l Cove r


# • #2B : #2 A + Groundwate r Control s


# • #2C : #2 A wit h Alt

. Channe l Alignmen t

> #3A : Soi l Cove r wit h Geosyntheti c Barrie r
• #3B : #3 A + Groundwate r Control s


# • #3C : # 3 A wit h Alt

. Channel Alignmen t

• #4A : Removal/On-Sit e Consolidatio n


# • #4B : Removal/Placemen t

i n Repositor y

> Preferre d Alternativ e 

# ASffiG O

# Alternativ e

# 1 N o Actio n N o furthe r cleanu p o r 

# remediatio n N o actio n provide s a baselin e fo r compariso n o f othe r 

# alternative s 

# ASARCO

# Alternativ e

#2 A Simpl e Soi l Cove r
> Regrad e impoundmen t surfac e and embankmen t

> Excavat e channe l fo r Californi a 

# Gulch t o carr y 500-yea r floo d even t

> Creat e a singl e combine d tailin g are a • Plac e 18 " cove r soi l ove r 6 " coarse san d an d 12 " compacte d tailing s


# > Revegetat e cappe d surfac e
> Construc t run-o n diversio n ditche s


# > Evaluat e effectivenes s vi a monitorin g progra m

> Commo n t o al l in-plac e closur e alternative s 

# ASAfiC OGEOSYNTHETIC CLA Y LINER

, K

= 3. 0 X ID' 9 CM/SE C GEONE T O R SIMILA R DRAINAG E MATERIAL

, K = 1 CM/SE C

- TAILIN G MATERIA

L r' - - *

. ~ - '~ \' -' , 4 "

^

ALTERNATIV E 3 : MULTI-LAYE R

COVE R SECTIO N

3%. 5:L OR 3:1 SLOPE ^ 6 " SAN D LAYER

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ALTERNATIV E 2 : SIMPL E SOI L COVE R SECTIO N 

### NOTE : 1

. THI S DRAWIN G I S NO T T O SCALE

. APACH E TAILING S IMPOUNDMEN T 

### ALTERNATIV E COVE R 

### SECTION S PROJECT : 5344. 4 REV : DATE :

SEPTEMBE R 199 9 B Y : CAA | CHECKED : FL C MFC

, Inc

. consulting scientists and engineers

# Colo r

Ma p T h e followin g ma p contain s colo r tha t does no t appea r o n scanned image

.

# E 5 i \

PON D NO

. 2

APCROXIWAT E LOC A O f RE-CONSTRUCTE

D 500-YEA R CALIFORNI A

o o B 

# 5 5 5 i i i u E" o t^~O
o_ o X Q

_ EXPUNAHO N SURFAC E WATE R SAMPL E LOCATIO N GROUNOWATE R MONITORIN G WEL L SOI L BORIN G MINI-PIEZOMETE R PIEZOMETE R LOCATIO N A 

# -i

PAVE D ROA D GRAVE L ROA D WATE R BUILDING/STRUCTUR E POWE R POL E ASARC O APACH E TAIUNG S IMPOUNDMEN T ALTERNATIVE S 2A

, 2B

, 3A

, & 3B : REGRADIN G PLA N PROJECT : 5344. 4 REV : DATE :

JANUAR Y 2000 B Y : JM K | CHECKED : MFG

, Inc

. consulting scientists and engineersTEMPORAR Y HAU L ROA D

TEMPORAR Y HAU L ROA D S.:.:; :

GUUC H TAILIN G IMPOUNDMEN T

ASARC O O U 7 - APACH E TAILING

S COVE R SOI L BORRO W ARE A PROJECT : 5344. 4 DATE :

JANUAR Y 200 0 B Y : JMK j CHECKED : MFG

, Inc

. consulting scientists and engineers

# Alternative s #2 B & 2 C •2B : Simpl e Soi l Cove r wit h Groundwate r Control s • Sam e a s Alternativ e #2A

, wit h additio n o f groundwate r control s • Instal l trenc h drai n immediatel y 

# downgradien t o f Mai n Impoundmen t •2C : Simpl e Soi l Cove r wit h 

# Channe l Alignmen t • Sam e a s Alternativ e #2A

, wit h alternat e channe l alignmen t • Construc t channe l t o conve y 

# Californi a Gulc h farthe r t o th e nort h 

# ASAfiC OPlo t time : 12:3 0 p m Plo t dote : 01-21-200 0

JM K D:\5344\5344-283.dw

g 01-20-200 0

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# l i • i

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# D f

|S
i r _ I P •yn m

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## I I

oALTERNATIV E 2A/3 A ALTERNATIV E 2C/3 C

o o EXPLANATIO N PAVE D ROA D GRAVE L ROA O WATCR I

I

Q_Q

. ASARC O O U 7 - APACH E TAILING

S CHANNE L ALIGNMEN T 2A/3 A VS

. 2C/3 C PROJECT : 5344. 4 REV : DATE :

JANUAR Y 200 0 B Y : JMK I CHECKED : MFC

, Inc

. consulting scientists and engineers

# Alternativ e

#3 A
Soi l Cove r wit h Geosyntheti c Barrie r Sam e a s Alternativ e #2A

, excep t multi-laye r cove r instea d

o f simpl e soi l cove r 

# Construc t multi-laye r cove r system , wit h 18 " cove r soi l ove r 

# geotextil e drainag e ne t an d geosyntheti c barrie r 

# ASWC O

# Alternative s #3B & 3C •3B : Soi l Cove r wit h Geosyntheti c Barrie r wit h Groundwate r Control s • Sam e a s Alternativ e #3A

, wit h 

# additio n o f groundwate r control s • Instal l trenc h drai n immediatel y downgradien t o f Mai n Impoundmen t 

# •3C : Soi l Cove r wit h Geosyntheti c Barrie r wit h Channe l Alignmen t • Sam e a s Alternativ e # 3 A

, wit h 

# alternat e channe l alignmen t • Construc t channe l t o conve y Californi a Gulch farthe r t o th e nort h 

# ASARCO

# Alternativ e

#4A

Remova l an d On-Sit e Consolidatio n • Completel y remov e tailin g material fro m Mai n an d Nort h Impoundment s 

# • Transpor t material t o on-sit e consolidatio n are a a t the Hecl a (Malt a Gulch ) Tailin g Impoundment s (prepar e area s first )


# • Ca p consolidatio n are a wit h simpl e soi l cove r 

# • Regrad e excavatio n are a and/o r 

# plac e impor t material

, a s neede d 

# • Revegetat e consolidatio n sit e and

remova l are a 

# ASARO O

# Alternativ e

#4 B

Remova l an d Disposa l i n On-Sit e Repositor y 

# Completel y remov e tailin g material fro m Mai n an d Nort h Impoundment s 

# Develo p ne w repositor y i n uppe r Orego n Gulch

, alon g wit h hau l road s 

# an d runon/runof f control s Transpor t materia l t o ne w repositor y 

# C a p repositor y wit h multi-laye r cove r Revegetat e repositor y an d remova l

area s 

# ASflfiC O

# msmu p~\\

o o c O C CN
a- 1 LEGEND :
C M

0 ) a ) E o '^" D ~O~C> Q.C L ALTERNATIV

E 4A : POTENTIA L ROUTE S T O MALT A GULC H ALTERNATIV E 4B : POTENTIA L ROUTE S T O OREGO N GULC H APPROXIMAT E LOCATIO N O F MINERAL BEL T BIK E TRAI L ASARC O O U 7 - APACH E TAILING

S POTENTIA L TRANSPOR T ROUTES T O CONSOLIDATIO N AN D REPOSITOR Y SITE S PROJECT : 5344. 4 DATE : JANUAR Y 2000 REV : B Y

: JMK | CHECKED : MFC

, Inc

. consulting scientists and engineers

# Evaluatio n Criteri a Overal l protectio n o f huma n healt h

an d th e environmen t 

# Complianc e wit h ARAR s Long-ter m effectivenes s an d 

# permanenc e Reductio n o f toxicity , mobility.

, o r 

# volume throug h treatment Short-ter m effectivenes s 

# Implementabilit y Cos t 

# Stat e acceptanc e Communit y acceptanc e 

# ASARCOTABL E 7- 1 Summar y o f Comparativ e Analysi s o f Remedia l Alternative s OU7

- Apach e Tailing s

evaluatio n Criterio n Dveral l protectio n
o f human healt h and t h e environmen t "omplianc e wilt i ARAR s .XMig-ler m effectivenes s and permanenc e deductio n o f toxicity , mobility

, o r volum e Sliort-lur m effectivenes s

niplcmc n labilit y

Cos t
Stat e acceptanc e * Communit y acceptanc e * N

o Actio n Alternativ e # 1 N o l protectiv e o f human healt h and the environmen t Doe s not compl y wit h ARAR s N o long-ter m decreas e i n loadin g t o groundwate r Minima l reductio n (16% )

o f mobility

. N o reductio n o f toxicit y or volume N o short-ter m reductio n i n ris k

Readil y implementabl e

$ 0 Simple Soi l Cove r Alon e Alternativ e #2 A Protective

, woul d mee t RAO s fo r impounde d tailin g Woul d compl y wit h ARAR s
Ver y good long-ter m effectivenes s an d permanenc e Mobilit y reduced b y 88%

. N o reductio n o f toxicit y
o r volum e Moderat e short-ter m effectivenes s du e t o ris k durin g regradin g
Goo d t o moderat e mpteme n lability

, excavatio n an d acces s consideration s $3,641.88 3 Wit

h Groundwate r Control s Alternativ e #2 B Protective

, woul d mee t RAO s fo r impounde d tailin g Woul d compl y wit h ARAR s
Ver y goo d long-ter m effectivenes s an d permanenc e Mobilit y reduce d b y 88%

. N o reductio n o f toxicit y
o r volum e Moderat e short-ter m effectivenes s du e t o ris k durin g regradin g

Moderat e technica l implementability ; difficul t trenchin g du e t o larg e dept h
13,973,38 3 Alternat

e Channe l Alignmen t Alternativ e #2 C Protective

, woul d mee t RAO s fo r impounde d tailin g Woul d compl y wit h ARARs Goo d long-ter m effectivenes s an d per m a n e n c o Mobilit y reduce d b y 88%

. N o reductio n o f toxicit y
o r volum e Low short-ter m effectivenes s du e t o ris k durin g regradin g
an d workin g wit h we t tailin g Moderat e t o lo w implementability

, du e t o difficultie s excavatin g
an d workin g wit h larg e volum e o f we t tailings

. $4,127,05 7 Mult i Laye r Cove r Alon e Alternativ e #3 A Protective

, woul d mee t RAO s fo r impounde d tailin g Woul d compl y wit h ARAR s Ver y goo d long-ter m effectivenes s an d permanenc e Mobilit y reduce d b y 96%

. N o reductio n o f toxicit y
o r volum e Moderat e short-ter m effectivenes s du e t o ris k durin g regradin g
Goo d t o moderat e implementability

, excavatio n an d acces s consideration s $4.077.73 6 Wit

h Groundwate r Control s Alternativ e # 3 B Protective

, woul d mee t RAO s fo r impounde d tailin g Woul d compl y wit h ARAR s
Ver y goo d long-ter m effectivenes s and permanenc e Mobilit y reduce d b y 96%

. N o reductio n o f toxicit y
o r volume Moderat e short-ter m effectivenes s du e t o ris k durin g regradin g

Moderat e technica l mplementability ; difficul t trenchin g du e t o larg e dept h
$4,409.23 6 Alternate

Channe l Alignmen t Alternativ e #3 C Protective

, woul d mee t RAO s fo r impounde d tailin g Woul d compl y wit h ARAR s Goo d long-ter m effectivenes s an d permanenc e Mobilit y reduce d b y 96%

. N o reductio n o f toxicit y
o r volum e Lo w short-ter m effectivenes s du e t o ris k durin g regradin g
an d workin g wit h we t tailin g Moderat e t o lo w mplementability

, du e t o difficultie s excavatin g
an d workin g wit h larg e volum e o f we t tailings

. $4,562,91 0 Remova l

Wit h On-sit e Consolidatio n Alternativ e #4 A Protective

, woul d mee t RAO s fo r impounde d tailing Woul d compl y wit h ARAR s
Ver y good long-ter m effectivenes s an d permanenc e Mobilit y reduce d b y 96%

. N o reductio n o f toxicit y
o r volum e Lo w short-ter m effectivenes s du e t o ris k durin g remova l and transport , highe r potentia l T o r release s an d increase d duratio n Difficultie s associate d wit h arg e volume

, excavation / wate r handling

, an d developmen t o f consolidatio n sit e $12,060.10 0 Deposi t

in On-sit e Repositor y Alternativ e M4 B Protective

, woul d mee t RAO s fo r impounde d tailin g Woul d compl y wit h ARAR s
Ver y goo d long-ter m effectivenes s and permanenc e Mobilit y reduce d b y 96%

. N o reductio n o f toxicit y
o r volum e Low short-ter m effectivenes s du e t o ris k durin g remova l and transport , highe r potentia l fo r release s an d increase d duratio n Difficultie s associate d wit h arg e volume

, excavation / wate r handling

, an d developmen t o f repositor y sit e $13,177.20 0

NOTES : Alternativ e #1 : N o Actio n (beyon d remova l o f Tailin g Pond s Nos

. 2 an d 3 ) Alternativ e W2A : Cove r soi l + 6 " drainag e laye r + 12 " compacte d tailing s ove r tailing s Alternativ e #2B: Alternativ e #2 A plu s graundwale r control s Alternativ e #2C : Alternativ e #2 A wit h alternat e channe l alignmen t fo r Californi a Gulch Alternativ e //3A : Cove r soi l + drainag e ne t + geosyntheli c clay line r ove r tailing s Alternativ e #3B : Alternativ e #3 A plu s groundwate r control s Alternativ e #3C : Alternativ e #3 A wit h alternat e channe l alignmen t fo r Californi a Gulc h Alternativ e W4A : Removal an d on-sit e consolidatio n Alternativ e #4B : Remova l and disposa l i n an on-sit e repositor y * Thos e criteri a wil l b e evaluate d afte r th e publi c commen t period

.

J:\5344\5344-4\FS\TAB7- 1

.WB2 Pag e 1 o f 1 MFG

. Inc

.

# Propose d Pla n Alternativ e #3 A Soi l Cove r wit h 

# Geosyntheti c Barrie r


# flSflfiC O

# Alternativ e

#3 A

- 

# Propose d Pla n Provide s overal l protectio n o f huma n healt h an d th e environmen t Achieve s RAO s Complie s wit h ARAR s 

# Provide s permanenc e and long-ter m effectivenes s Can b e implemente d wit h standar d technologie s 

# Reduce s existin g meta l loadin g t o 

# surfac e wate r an d groundwate r Eliminate s ris k t o terrestria l ecosyste m 

# ASARCO

# Cos t Summar y Alternativ e #3 A
• Estimate d Capita l Cost s $2,504,00 0 • Annua l O& M Cost s $85,00 0 

# • Five-Yea r Revie w Cost s $41,50 0 • Tota l Present Wort h $4,078,00 0 

# ASARCO

# OU 7 Schedul e o f Wor k
Initiat e constructio n i n 2000 Anticipate d completio n i n 

# 200 1

ASARCO