UNITE D STATE S ENVIRONMENTA L PROTECTIO N AGENC Y

REGIO N VII I

9 99 18th STREET - SUITE 500

DENVER , COLORADO 80202-2466

375918

Ref: 8EPR-S R

ACTION MEMORANDUM- - ENFORCEMENT

DATE: August 15, 1996

SUBJECT: Request for Removal (Response ) Action s at Asarco' s Work Area of the California Gulch National Priorities Lis t Sit e (Site) , Leadville , Colorado: ACTION MEMORANDUM fo r P RP Financed Removal Action s Addressin g Mine Wast e Rock Piles Located in the Residential Populated Areas, a

portion of Operable Unit 9// (OU 9) .

FROM: Rebecca Thomas , 8EPR-SR

T O: Max H. Dodson, Assistan t Regional Administrator Offic e of Ecosystems Protectio n

and Remediation

Final NPL Sit e ID f t 29

CERCLI S ID # COD980717938

Category of Removal: Non-Tim e Critical

I . Purpose

Thi s Actio n Memorandum documents the Agency' s decision to

conduct the Removal (response ) Actio n described herein for the

mine waste rock pile s located within OU 9, Residential Populated Areas, of Asarco' s Work Area of the California Gulch Superfun d Sit e (Site) . The evaluation of alternatives

available to address these mine waste rock pile s is contained

in the "Draf t Mine Waste Engineering Evaluation/Cos t Analysi s

(EE/CA) , California Gulch Superfun d Site , Leadville , Colorado

which is dated December 1995. The Draf t EE/CA and Asarco' s

responses (Letter dated Jul y 23,1996 ) to EPA' s comments

represent the final EE/CA for these response actions.

T he EE/CA was prepared by Asarco, Inc. , Denver, Colorado, for

a portio n of the Sit e within its "area of responsibility " as

defined by the August 26, 1994 Consent Decree between the United State s and Asarco, Inc. The Removal Actio n for the

mine waste rock pile s within the residential populated areas

is consistent with the overall remedial activities to be

undertaken by Asarco, Inc. at OU 9. As such, the Removal Actio n alternatives evaluated in the EE/CA are considered to

represent interim response actions, but the removal

alternatives will also be evaluated as final remedial

Printed on Recycled Paper
alternatives i n the Feasibilit y Stud y (FS) an d Record of Decision (ROD) for OU9. The Removal Actio n is not intended to

be a final action, but is rather intended to contribute to the

efficien t performance of the remedial action for OU 9. The R OD for OU 9 will ultimatel y determine whether further

remedial actions are required.

T he primary goals of this Removal Actio n are to reduce the

exposure of the residential populatio n to metals contamination

in the mine waste rock pile s and to reduce the risk to the

aquatic and terrestrial ecosystems by reducing the release of

contaminated material into the environment from the mine waste

rock pile s in the residential populated areas. Thi s Removal Actio n will also reduce the potential for leaching and

migration of metals from the mine wastes into surface and

ground waters.

Remedial action objectives were identified in the Final Screening Feasibilit y Stud y for Remediation Alternatives at

t h e California Gulch NP L Site , Leadville , Colorado (SFS) ,

(EPA, 1993a) . Consisten t with the SFS, removal action

objectives for the residential populated areas are:

O Control wind and water erosion of mine waste rock

material from the source locations

O Control leaching and migration of metal s from mine

waste rock into surface water

O control leaching and migration of metal s from mine

waste rock into groundwater

Removal alternatives to directl y remediate surface water or

ground water in the residential populated areas are beyond the

scope of this EE/CA . Consistent with the Consent Decree and Work Area Management Plan (WAMP), Applicabl e or Relevant and Appropriate Requirements (ARARs) specifi c to surface water and

groundwater are not included as performance standards for

evaluation of this response action.

I I. California Gulch Sit e - Condition s an d Background

T he California Gulch Sit e was listed on the National Priorities Lis t on September 8, 1983. The Sit e is in a mining

area covering 16 1/2 square miles of a watershed area that

drains along California Gulch to the Arkansas River. Startin g

in 1859, the area was mined extensively for gold, lead,

silver, copper, zinc, and manganese. California Gulch

collect s runof f that drains numerous abandoned mines and

wastes from mining, millin g and smelting. Seventy-five known

mill s dumped tailings into 5-6 miles of drainages and 6
impounded tailings dumps surround the Cit y of Leadville . Many

smelters operated at various times around the Cit y processing

silver, lead, and zinc. Heavy metal residues are present in

much of the City . The Arkansas River, which receives water

from the California Gulch, has been classified as a

recreational resource, and is used heavily for irrigation,

livestock watering, public water supplie s and fisheries . Approximatel y 4,000 live in nearby Leadville and Lake County.

(Sit e Location Maps are attached as Exhibits 1 & 2, Figure s 1

& 1-1 respectively. )

III . Condition s an d Background

T he mine waste rock pile s evaluated in the EE/CA are located

throughout the populated area of eastern Leadville. (Se e

attached Exhibit 3, Figure 3.1. ) During the Mine Waste Remedial Investigation , 8 of the 38 pile s were found to be

stockpile s of construction materials or to not pose a threat

to human health or the environment. However, one pil e

representing this group was evaluated with the remaining 30

pile s as a control to confirm the EE/CA' s findings . Therefore , a total of 31 piles were investigated in detail . Only those pile s which contain surface concentrations of total

lead greater than 2000 ppm will be subject to the Removal Action . (Figur e 3.1 of the EE/CA) . However, since EPA has

proposed an Actio n Level for the mine waste rock pile s of

3,500 ppm lead, Asarco will reserve the optio n to remove or

leave in place pile s between the 2000 ppm action level based

on the Mine Waste Work Plan and Asarco' s WAMP (appendix to the

consent decree) and the 3500 ppm action level for lead

selected in this Removal Action . Other factors that were

considered in selectin g this Removal Actio n are:

O The mine waste rock pile s are in or near a populated area;

O Metal s concentration in the pile s exceeds

background level (2000 ppm lead for this Removal Action) ;

O The piles pose an attractive nuisance in the

area which may increase exposure to elevated

metals;

O Some piles are steep and may be unstable in

their present condition ; and,

O The piles are subject to erosion by wind and

water which may spread contaminants.
T he mine waste rock pile s are being addressed prior to a Record of Decision (ROD) . The mine waste rock pile s may

contribute to lead exposure in the residential area. Therefore , it is necessary to evaluate alternatives for each

pil e according to its chemical content, location and current

condition. The final remedial actions are to be established

at the time of the ROD. A summary of maximum metals concentrations in the mine waste

rock pile s is shown in Table 2.1 of the EE/CA which is

attached as Exhibit 4.

T he engineering and geochemical evaluation of the mine waste

rock pile s were conducted to characterize the existin g waste

pile s to facilitat e development of removal alternatives. Geochemical analyses were performed to evaluate which pile s

would require a removal action. The screening process is

shown in attached Exhibit 6, Table 3.2.

Exhibit 3, Figure 3.1 of the EE/CA identifie s the pile s in

each category.

Only mine waste rock pile s containing lead levels greater than

3,500 ppm are being addressed as part of this Removal Action . A ny appropriate response actions for mine waste rock pile s

containing lead levels less 3500 ppm lead wil l be selected in

the final ROD for OU 9.

B. Other Action s to Date

There have been no previous actions taken on the mine

waste pile s in the residential populated areas. There

have been removal actions involving surface soils in the

residential areas under the Kids Firs t program.

C. Stat e and Local Authorities Roles

O The Draf t EE/CA was issued for public comment and a public hearing was held to discuss this Removal Action . EPA, CDPHE , Lake County and ASARCO

commented on the Draf t EE/CA . Asarco responded to

those comments by letter dated Jul y 23, 1996.

O Cultural Resources Findings: Leadville has been

classified as a National Histori c Landmark. Therefore , the identificatio n an d evaluation (ID&E)

of the potential effect s of remediation of historic

properties was required for this Removal Action . T he ID&E was performed in two phases: a reconnaissance-level examination in January 1995,
a nd a detailed Clas s III survey in June 1995. The

presence of intact, substantial , structural remains

as well as visual prominence/contributio n of the

cultural landscape, determines the potential for a

resource to be recommended as eligibl e for listin g

o n the National Register of Histori c Places (NRHP) .

Eligibilit y for listin g can be a consideration in

the selection of a response action. Each mine waste

rock pil e within Asarco' s area of responsibilit y was

examined. The results are summarized in the Cultural Resource Management Summary which is

attached as Exhibit 7, Table 7-2. A mitigatio n pla n

shall be prepared for any cultural resources

adversely affecte d by this Removal Action . Thi s

mitigatio n pla n will be implemented as part of the Removal Action , afte r the pla n has been approved by SHPO . O Cit y of Leadville: EPA has notified the citizens of Leadville by the release of and acceptance of public

comment on the Engineering Evaluation/Cos t Analysi s

(EE/CA) concerning this removal action. Under CERCLA § 121(e) , no Stat e or local permits are

required for the removal action since this removal

action will be conducted entirely on-site.

I V. Threat s to Public Health or Welfar e or the Environment,

and Statutor y and Regulatory Authorities

Residents are exposed through contact with the mine waste

materials which contain elevated metals levels. Exposure of

children is of particular concern. The exposure pathway is by

wind erosion and direct ingestion. There is also evidence of

direct contact of sensitive human and ecological population s

to this material.

A Baseline Aquatic Ecology Risk Assessment (BAERA), California Gulch, Leadville, Colorado (Roy F . Weston , Inc. [WESTON] ,

1994 ) identifie s the Site-wide impact of mine waste

contamination on the aquatic ecosystems at the Site . The BAERA provides a conceptual model of Site-wide exposure for

aquatic receptors.

V. Endangerment Determination

Actual and/or threatened releases of hazardous substances

from mine waste rock piles in the residential populated areas,

if not addressed by implementin g the Removal Actio n selected

in this Actio n Memorandum, may present an endangerment to

public health, or welfare , or the environment.
V I . Proposed Actions/Performanc e Standards/Estimated Cost s

A. Proposed Action s

A .I The mine waste rock will be hauled directl y to the

end use location. A potential end use would be to

utilize the mine waste rock material for

capping/stabilizatio n of other contaminated areas

on-site. Also , the waste may be used to fil l in

sink holes and subsided mine shaft s which

occasionally appear in Leadville followin g

significan t storm events. EPA approves this use

provided the contaminated material does not come

into contact with groundwater and that the top two

fee t of any backfil l activity uses only materials

below the 3500 ppm action level for lead.

A .2 Sinc e EPA has selected a 3500 ppm lead action level

f or the mine waste rock pile s in this Actio n Memorandum, Asarco may remove or leave in place

pile s between the 2000 ppm action level based on the Mine Waste Work Plan an d Asarco' s WAMP (appendix to

the consent decree) and the 3500 ppm action level

f or lead selected in this Actio n Memorandum. Every

effor t will be made to accommodate the propert y

owner' s preference and to take into account the

interest of the Lake County Histori c Preservation Advisory Board.

A .3 All pile s with a lead concentration exceeding 3500

ppm lead will be removed with mitigatio n being

performed as specified by SHPO.

A .4 Stockpilin g of mine waste rock will occur only to

accommodate extenuating circumstances and would be

on a very limited basis in terms of time and

quantity.

A .5 A fugitive dust monitoring program will be

implemented.

A .6 If direct re-use of the materials is not possible

within two years, a suitable stockpile area will be

identified and developed. Mine waste rock that

exceeds the action level (3500 ppm lead) will be

moved to this stockpile location for long-term

management.

A .7 For waste pile s that are removed, confirmatio n

testin g at the base of the pile s will be used to

evaluate soil-lead concentrations of the foot-print . If lead concentrations at the base of a pil e are
acceptable, no further evaluation is necessary other

than maintenance of vegetation until it becomes

established. Remaining waste rock or pre-existin g

soil with lead levels greater than 3500 ppm will be

capped and revegetated. Cap materials would be

obtained from a local borrow source and/or from mine

waste rock pile s with lead concentrations below the

action level.

B. Applicabl e or Relevant and Appropriat e Requirements (ARARs)

ARARs are identified in Appendix F of the EE/CA . They will be met by implementing the Performance Standards

identified in Sectio n C.

1. Chemical Specifi c ARARs

Chemical-specifi c requirements are based on

health or risk-based concentration limit s or

discharge limitation s in environmental media (i.e .

water, air) for specifi c hazardous chemicals. These

may be used to set cleanup levels for chemicals of

concern (in this case, metals ) in the designated

media, or to set a saf e level of discharge (e.g.

waste water discharge, taking into account water

quality standards) where a discharge occurs as part

of the removal activity.

Potential Chemical -Specifi c ARARS/TBCs are shown on

attached Exhibits 8 & 9, Table s 4.1 and 4.2 of the

EE/CA .

2. Actio n Specifi c ARARs -

Action-specifi c ARARs are activity-based

requirements triggered by the particular removal

activities selected. Regulation s regarding worker

health and safet y (i.e. OSHA requirements) are not

technicall y ARARs as they are not environmental or

public health requirements.

Potential Action-Specifi c ARARs are shown on

attached Exhibit 10, Tabl e 4.4 of the EE/CA .

In additio n to the Action-Specifi c ARARs identified

in Exhibit 10, Tabl e 4.4, RCRA Subtitl e C may be

relevant and appropriate if the wastes fai l Toxicit y Characteristic Leaching Procedure (TCLP) or if they

exhibit other characteristics of a RCRA hazardous
waste. Portions of RCRA Subtitl e C that address low

permeabilit y cover of characteristic wastes and

provide for the continued collectio n of leachate and

continued runon and runof f control may be relevant

and appropriate to this Removal Action .

3. Location Specifi c ARARs -

Location-specifi c ARARs are restrictions placed on

the types of activities that may occur in particular

locations . The location of the waste may be an

important characteristic in determining its impact

on public health and the environment; thus state

standards ofte n establish location-specifi c ARARs . These ARARs may restrict or preclude certain

remedial actions or may appl y only to certain

portions of a site. Examples of location-specifi c ARARs include federal and state requirements for

preservation of historic landmarks, endangered

species and wetlands protectio n and floodplai n

restrictions on management of hazardous waste. F or additional information , refer to Tabl e F.I

attached.

Potential Location-Specifi c ARARs are shown on

attached Exhibit 11, Tabl e 4.3 of the EE/CA .

C. Performance Standards

T he ARARs are being met through the Performance Standards . Performance Standards shall be attained

consistent with ARARs and EPA approved removal action. T he Performance Standards are described below:

1. The Removal Actio n as designed and constructed

shall include provisions to ensure that there are no

visible emissions (dust ) from the mine waste rock

pile s in the populated residential areas during and

followin g construction.

2. The Removal Actio n as designed and constructed

shall include provisions to ensure that there is no

erosion of the mine waste rock piles or sediments

due to rain or snow melt.

3. The design shall contain requirements to ensure

that erosion, run-on, and run-of f are prevented and

to ensure slope stability . Rain, flood and snow

melt shall not be allowed to run onto or from the
tailings area. All slopes shall be graded to be

permanently stable.

4. Contaminated material will be used as fil l material

only if it does not come in contact with

groundwater.

5. The top two fee t of any fille d area will have a lead

concentration not exceeding 3500 ppm lead.

6. The Removal Actio n will be reviewed by SHPO and

proper mitigatio n will be designed and implemented

f or any adverse effect s on cultural resources.

7. An air monitoring program will be implemented to

ensure fugitive dust emissions are not being

released from the mine waste rock piles .

8. A long-term maintenance program may be implemented,

if required by the final ROD for OU 9, to ensure the

long-term effectivenes s of this Removal Action .

D. Projec t Schedule

T he construction of this Removal Actio n shall be

completed within two years of the date of this Actio n Memorandum. Upon completio n of construction of this Removal Actio n and attainment of the Performance Standards , long-term maintenance and monitoring will be

initiated, if necessary.

If direct re-use of the materials is not accomplished

within two years, a suitable stockpile area wil l be

identified and developed and mine waste rock that exceeds

the action level (3500 ppm) will be removed to this

stockpile location for long-term management.

E. Estimated Cost s

Asarco' s estimated cost for this Removal Actio n is

$1,500,000.

VII. Expected Change in the Situatio n Should Actio n Be Delayed or N ot Taken

Should this Removal Actio n be delayed, or not taken at all ,

potential risk of exposure to heavy metals contained in the

mine waste rock, groundwater and surface water will continue

to exist.
VIII . Outstandin g Polic y Issues

A Record of Decision will be issued for OU 9 of the Sit e

selectin g the final remedial action including the mine waste

rock pile s in the residential populated area.

I X . Enforcement

Asarco, Inc. is the party that has agreed to implement

response actions for the OU 9 portions of the Site .

X. Re c ommenda t i on

Thi s decision document represents the selected Removal Actio n

f or a portio n of OU 9 of the California Gulch Superfun d Site ,

in the Cit y of Leadville , County of Lake, Stat e of Colorado. It was developed in accordance with CERCLA , as amended, and is

not inconsistent with the NCP. Thi s decision is based on the Administrative Record for the Site .

Condition s in the residential populated areas meet the NCP

Sectio n 300.415(b)(2 ) criteria for a removal and I recommend

approval of the proposed removal action.

APPROVAL

M ax H. Dodson Assistan t Regional Administrator Offic e of Ecosystems Protectio n

and Remediation

DISAPPROVA L

M ax H. Dodson Assistan t Regional Administrator Offic e of Ecosystems Protection

and Remediation

10
NOT JO SCALE

CALIFORNIA GULCH SVPERFUNb SITE

664 OIOO

KfSWLOC.DWG

fsign lly

J.RAY

ii»i fly . K.COHR4TH

RESURRECTIO N MININ G COMPAN Y O N C UNITC O «ANI < CCNTC 1 I>00 IMC1XH (tnEC I

OtMVtH. C<XOMAOO *OtB>

.S'ru/ r

W 95

CALIFORNIA GULCH SITE

GENERAL LOCATION

EXfflBIT l

,1.1
E

1

 • r-5 ••x-

Rfr-TUNNEt ^ ^

LEADVILL E DRAINAG E TUNNE L

;*. .i*K ^hT

Stray HOTM Gulch

Storr Ditch

CALIFORNIA GULCH

»/

Y AK TUNNEL

^^

•CALIFORNIA GULCH

Denver, Colorado

TITL E SIT E LOCATION MAP

CLIENT/PROJEC T DRAWN ASARCO MINE WAST E EE/CA

RB

CHECKED BES

REVIEWED C AD

OATE

 DEC 1995

SCALE AS SHOWN RLE NO. 2819A045

EXHIBIT 2

FIGURE NO. 1-1
MIDAS s

GRAY EAGLE

PGLAS S PENDER Y i i v

MINERA L GROU P I MIN E WASTE , PILES

MIN E WAST E PIL E WITH P b > 2000 pp m

MIN E WAST E PIL E WITH P b < 2000 pp m 400

SCAL E IN FEET

iZ!

800 1600

Denver, Colorado

TTOE MINE WAST E PLES IN T HE POPULATED AREA

9

CLIENT/PROJECT DRAWN ASARCO MINE WAST E EE/CA

RB

CHECKED A RC REVIEWED C AD

DATE

 DEC 1995

SCALE r=8oo- EXHmrrs

FILE no. 2819A148IF1GUR E NO. 3 -I
TABLE 2.1

SUMMARY OF MAXIMUM METALS CONCENTRATIONS MINE WAST E PILES

Mine Waste Pile*

16

79

103

120

1 41

150

1 51

156

172

1%

I'enros c

Mineral Group

4

2

3

5

4

4

4

5

2

4

n /a

Sampl e Type S MC MW S MC MW S MC MW S MC MW S MC MW S MC MWS M C MW S M C MW S M C MW S MC MW S M C MW

Antimony Arsenic

255

94.7

.

246

117

261

290

67.0

73.4

283

139

71.3

„

500

- ' 89

3.2

72.4

65.9

147

141

276

578

Barium Beryllium

64

49.2

168

302

82.8

- ,

192

200

417

154

_

30 -- '

„ .

76

_

90

736

198

.

242

276

567

Cadmium

135

248

32.9

18.5

59.5

-

25.5

13.8

69.2

57.8

15.4

230

52.4

187

47.1

5.1

51.5

48.7

6

116

108

417

Chromium

-

-

4.1

3.6

3.5

-

--

13.2

4.8

-

-

-

' . .13.2

-

6.5

5.4

5.6

-

20.6

11.1

7.8

Copper

236

87.6

17.5

11.6

332

-

58.8

84.9

116

117

-

280

-

827

-

8.8

36.1

12.1

-

22.5

782

433

Lead

14.000

9,850

937

10,600

13,700

26,7(X )

15.100

2,080

8,950

66,400

5,410

6,200

1,440

16,100

6,310

84.6

4,010

7,270

7,250

2.130

9.360

40,700

Manganese

6,180

50.200

4,520

3,280

2,970

-

4,24()

1,220

17,800 '"

1,730

-

8,890

-

4,790

-

259

10,400

3,480

-

1,360

12,900

10,100

Mercury

0.79

1.0

1.1

1.5

0.88

-

4.5

0.81

1.4

0.62

-

0.64

--

0.36

-

-

1.7

1.0

-

0.9

1.9

--

Nicke l Silver

11.0 10.2

6.8

74.5

4 33

.

-

13.2

.

65.7

-

7.6

14.5

-

-

.

12.6 41.7

Thallium

2.3

-

1.9

10

--

-

1.3

1.5

-

-

-

1.3

-

3.7

4.1

3.2

/inc

16,900

57.100

16.901)

5,680

'11,10 0

32,000

4,040

2,000

9,740

9,350

2,810

25.800

10.300

7.810

6,940

998

11,700

7,800

870 II.51K )

14,200

48,800

A l l units in ing/kg S MC = Surfac e mine waste composite samples MW = Subsurfac e mine waste samples FS - Foundatio n soil s samples

— Not detected or not analyzed

EXHIBIT 4
38 MINE WAST E PILES IN RESIDENTIAL AREA

30 CATEGORY 2 +, 3 PILES AND 1 CATEGORY 1 PILE RESIDENTIAL AREA

SAMPLIN G A N D ANALYSI S F OR TOTAL LEAD

NO REMOVAL/REMEDIAL ACTION ON PILES UNTIL

COMPLETION OF ROD (INCLUDIN G N O ACTION ALTERNATIVE) OR MAY BE USED ELSEWHER E ON SITE

ADDITIONA L GEOCHEMICA L A N D GEOTECHNICA L INVESTIGATION ON BULK SAMPLES

IDENTIFICATIO N A ND EVALUATION OF REMEDIAL/REMOVA L ALTERNATIVE S

5-r*i ASSOCialES Denver, Colorado

TITL E M NE WAST E

EE/CA FLOW CHART

CLIENT/PROJEC T DRAWN ASARCO M NE WAST E EE/CA

RB

A RC

REVIEWED C AD

OAT£

 DEC 1995

SCALE N T S

RLE NO. 2819A147

EXHIBIT S

FIGURE NO. 3-2
TABL E 3.2

SUMMAR Y TABLE

Tile Pile Mineralogy Estimated Soil Lead

Number Nam e Group Class. Volume Content 0" to 2"

(cyds) (ppm )

12

13

14

15

16

17

18

19

20

22

23

24

26

27

28

31

32

33

34

35

36

108

109

110

1 11

140

 207

329

331

339

340

Corando/Northern

I-slc y

llihschle

Ilibschlu

Coronado

Coronado/Noriher n

Coronado Wolcol t

Midas

Gray Eagle/Bison Kent/Cresen t

Ken t Pocahontas

Starr/Laz y Bil l Stair

. Pocahoiuas/Pendery Pocahontas/ Weldon #1

Weldon/Weldo n #2

Bolm

Midlan d

Glas s Pendery T ut hot

Hope/Las t Chip Luzeine

Ypilant i

Ypsilanti/Ypsilanl i B

Bolin D on Air Aetn a

P.O.S . P.O.S .

5

2

2

3

4

3

2

2

2

2

3

3

2

2

2

3

2

2

2

1

2

2

2

2

2

2

2

2

2

2

2

19,600

700

5,600

2,700

16,600

3,300

10,500

8,800

28,500

12,000

500

300

5,800 ,

9,200

16,300

200

10,200

39,900

9,200

8,350

2,600

2,300

6,800

iso

200

2,800

800

33,300

8,900

7,400

12,200

1540

3150

22300

19400

9240

4200

2370

20700

2680

5310

1170

4220

14100

3380

10700

349

2120

2360

568

3340

1070

6220

27700

4800

6270

5700

3210

1730

723

1560

2250

N et Acid Neutralizin g Potential

(Tons/KT )

n /a

320

112.4

201.8

235.6

414.8

126.4

-0.6

24.7

89.6

n /a

22.3

219.4

379.3

610.1

n /a

526.2

424.1

n /a

547.9

n /a

410.6

163.4

132.7

485.4

301.8

163.1

n /a

n /a

n /a

558.5

ANP/AG P Ratio

n /a

n /a

6.4

10.5

5.3

25.1

20.3

1

7.6

11.6

n /a

5.8

8.2

26.8

103.7

n/a

188.1

72.4

n /a

176.3

n /a

120.4

30

425.6

46.7

43 '

174.9

n /a

n /a

n /a

224.4

Method

1312

(Pass/Fail)

n /a PAS S

PASS

PAS S

PAS S

PAS S

PASS

PAS S

PAS S

PAS S

n /a PAS S

PAS S

PAS S

PAS S

n/a PAS S

PAS S

n /a

PAS S

n /a PAS S

PAS S

PAS S

PASS

PAS S

PAS S

n /a

n /a

n /a

PAS S

Assumed

uses

Classificatio n Description

SM

SM

SM

SM

SMSMSM

SM

SMML SMSM

SM

ML

ML

SM

SMSMSMSMSM

SM

Sand y sil t Sandy silt Sand y sil t Sand y sil t Sand y sil t

Sandy silt Sandy sil t

Sandy sil t

Sandy silt Sil t Sand y sil t Sandy sil t

Sandy sil t

Sil l

Sil t

Sand y sil t Sandy sil t

Sandy sil t

Sandy silt Sand y sil t

Sand y sil t

Sandy sil t

EXHIBIT 6
TABLE 7.2 CULTURAL RESOURCE MANAGEMENT SUMMARY

Pile No. - Name

(Smithsonian Site Number) MWP 13 - Estey

(5LK867) MWP 16, 17, 18 - Coronado

(5LK868)

MWP 20 - Midas

(5LK869)

MWP 22 - Gray Eagle

(5LK870) MWP 24 - Kent

(5LK871) MWP 32 - Pocohontas

(5LK872) MWP 33 - Weldon

(5LK873)

MWP 35 - Midland

(5LK874) MWP 108 - Turbot

(5LK875) MWP 140 - Ypsilanti

(5LK876) MWP 340 - P.O.S.

(5LK877)

Eligibility N ot Eligible

Eligible, both Individually and as

a contributing element of the Leadville Historic District

(5LK856) Eligible only as a contributing

element of the Leadville Historic District (5LK856) N ot Eligible

N ot Eligible

N ot Eligible

Eligible only as a contributing

element of the Leadville Historic District (5LK856) N ot Eligible

N ot Eligible

N ot Eligible

Eligible only as a contributing

element of the Leadville Historic District (5LK856)

District Status

N ot Contributing

Contributing

Contributing

N ot Contributing

N ot Contributing

N ot Contributing

Contributing

N ot Contributing

N ot Contributing

N ot Contributing

Contributing

Note: The above table includes only "Sites", not "Isolated Finds." All isolated finds at the Mine Waste Piles surveyed were determined to be Not Eligible and Not Contributing

Source: FEC. 1995.

EXHIBIT ?
TABL E 4.1

 -'SUMMARY OF POTENTIA L CHEMICAL-SPECIFI C ARARs/TBCS CALIFORNIA GULCH SUPERFUN D SIT E

Standard , Requirement , or Crileria Description Comment

Clea n Water Act (33 USC Sect . 1351-1376) Ambien t Water Quality Criteria (40 CFR Part

131; Qualit y Criteria for Water, 1976, 1980,

1986, 1987; Ambien t Water Quality Criteria

f or Selenium , 1987)

Clea n Air Act (-12 USC Sect . 7401-7642) National Ambien t Air Qualit y Standards C FR Pan 50)

(40

Nationa l Emissions Standards for Hazardous Air Pollutant s (40 CF R Part 61 )

Safe Drinkin g Water Act (42 U.S.C. 300)

Undergroun d Minin g General Performance Standards (30 CFR Part

717 )

Requires EPA and states to establish

ambient water quality control criteria

(AWQC) and standards, respectively, for

surface water based on use classification s

and the criteria stated under Sections 304(a)

and 303 of the Clean Water Act.

Establishes ambient air quality standards for

certain "criteria pollutants" to protect public

health and welfare.

Establishes emission standards for certain

industrial pollutant s and sources.

Establishes regulations to protect human

health from contaminants in drinking water

a nd establishes national drinkin g water

standards

Establishes minimum environmental

protection performance standards for

underground mining activities.________

Federal freshwater AWQCs may be "relevant and

appropriate" if contaminants are released to site surface

waters or if treated groundwaler is discharged to a

surface water. Colorado has its own state water qualit y

standards which could be considered "applicable," where

they are more stringent than the federal standards .

Applicabl e if any criteria pollutan t is emitted to the

atmosphere durin g remedial action operations from a

major source. Would only be an ARAR if the remedial action involves a

specifi c industrial category for which NESHAPs has been

established

Modified From EPA (1993)

EXHIBIT S

Colder Associate s
TABLE 4.2

POTENTIA L CHEMICAL-SPECIFI C ARARs/TBCs FEDERAL SURFAC E WATER QUALIT Y STANDARD S

CALIFORNIA GULCH SUPERFUN D SIT E

: :

 : -

:

 :

x :

 Parameter •^mm* ' S ul fate A

pH FP Temperature F P Total Dissolved Solid s I Aluminu m M Antimon y M Arsenic Cadmium Chromium . M Chromium II I ' • M Chromium VI M Copper M Cyanide Iron Lead Manganese M Mercur y Nicke l M Selenium M Silver M Thalliu m Zin c6.5-9 SS SS SS S

750 87

9,000 1,600

3.9(2) 1.1(2 )

1,700(2) 210(2)

16 11

18(2) 12(2)

22 5.2

1,000

82(2) 3.2(2)

2.4 0.012

1,400(2) 160(2)

20(b) 5(b )

4.1(2) 0.12

1,400(2) 40(2)

120(2) 110(2)

i^M^8^^ra^@^lffi^WP.M ^^^m^:m^^sms^j^^-^^s^w^m^^^ K

lli;:;jS/aiier;:arJd j '.feigfell l fe

 : FisB ;fcqhsMifljjiitiij|iij |

f IfiPlnp^bfi f iWf

 : l:>;: :

 1

: >;: !:::;;I^On1y<:;;;!filPP;

i

250,000

146 45,000

0.0022 0.0175

10

170,000 3,433,000

50

200

300

50 100

50 0.146

0.144 100

13.4

10

50

13 48

Explanalio n of Table AWQ C Ambien t Water Qualit y Criteria CVVA Clea n Waler Ac t SS Species Specific Hg/o micrograms per liter ( 1) Type abbreviations are: A = Anion ; 1 = Indicator ; FP = Field parameter; M = Metal ( 2) Hardnes s dependent criteria; value sel at hardness of 100 mg/L CaCo

3 ( a) EPA, Quality Criteria for Protection of Aquatic Life , 1986

( b) EPA, National Ambien t Water Qualit y Criteria for Selenium - 1987

horn EPA 1993

EXHIBIT 9

Golder Associates
TABL E 4.4 POTENTIA L ACTION-SPECIFI C ARARs CALIFORNIA GULCH SUPERFUN D SIT E

Standard , Requirement, Criteria, or Limitatio nCitatio n Description Comment

FEDERA L

Clea n Air Ac t

N ew Source Performance Standards

Solid Waste Disposal Act (SWDA as

amended by the Resource Conservation

a nd Recovery Act of 1976 (RCRA) Ma/ardous Material s Transportatio n A ct

Hazardous Material s Transportatio n Regulation s

Occupational Safet y an d Health Ac t

Federal Min e Safet y an d Health Ac t

STAT E Stale Solid Wast e Disposal Site s an d

Facilitie s Act CRS 30-20-101 to 118 Colorado Solid Waste Management

Regulation s

42 USC Sect . 7401-

7642

40 CFR 60

42 USC Sect. 6901-

6987

49 USC Sect . 1801-

1813

49 CFR Part s 107,

17M77

Establishes emission standards for

certain categories of industrial stationary

sources.

Regulates transportation of hazardous

materials.

29 USC Sect . 651-678 Regulates worker health and safety .

30 USC Sect . 800-962 Establishes requirements to protect

worker health and safety.

6CCR 1007-2 Establishes policy for licensing, locating,

constructing and operatin g of solid waste

facilities .

Only applicable if a remedial action creates air

emissions regulated by these standards .

Applicabl e i f the remedial action involves offsite transportatio n of hazardous materials . The

regulation s affectin g packaging, labeling, marking, placarding, using proper containers,

a nd reportin g discharges of hazardous

material s would be potential ARARs . Applicabl e for al l remedial actions under the . NCP . Applicabl e for al l remedial actions under the N CP conducted in and around mines.

Applicabl e i f remedial activitie s involve

disposal of solid waste materials . Permit s are

n ot required for on-sile activitie s at a site listed

on the NPL.

EXHIBIT 10

Modified Em m EPA IW 3 Golder Associates
TABLE 4.4

(Concluded)

Standard , Requirement, Criteria, or Limitatio nCitatio n Description Comment

Colorado Mined Land Reclamation Act Mineral Rules and Regulation s

Colorado Air Qualit y Control Act

Colorado Noise Abatemen t Act

Miscellaneous Regulations on the Collection of Aquatic Lif e

CRS 34-32-101 to 125

2CCR 407-1

5CCR 1001-1, 3,4,

5, 8, 10 CRS 25-12-101 to 108

2CCR 406-8, Ch. 13, Article HI ; Section

1316

Regulates all aspects of land use for

mining, including the location of minin g

operations and related reclamation

activities and other environmental and

socio-economic impacts.

Establishes emissions standards for PM

10 and lead.

Establishes maximum permissible noise

levels for particular time periods and

land use zones.

Requirements government the collection

of wildlif e for scientific purposes.

M ay be relevant and appropriate to remedial

activities involving drilling , water control

measures, and treatment and disposal of waste

piles . Permit not required for CERCLA sites.

Applicabl e if the remedial action creates

emissions of regulated materials . Relevant and appropriate to remedial activities

involving construction activities.

Applicable if remedial activities trigger the

need for biological monitoring.

Modifie d l-roi n lil' A 1993 Colder Associates
TABL E 4.3 SUMMARY OF POTENTIAL LOCATION-SPECIFIC ARARs CALIFORNIA GULCH SUPERFUN D SIT E

Requirement

Potentially Applicable

Potentiall y Relevant and Appropriate Comments

Location-Specific Laws/Requirements FEDERA L REGULATION S

E.O. 11988 Protection of Floodplain s

1. Limit s activitie s in floodplains . Floodplai n is defined as "the Yes

lowlan d and relativel y flat areas adjoinin g inland and coastal

waters includin g flood prone areas of off-shore islands ,

includin g at a minimum, that area subject to a one percent or

greater chance of floodin g in any given year." Federal agencies

must evaluate the potential effect s of actions taken in a

floodplai n and avoid adverse impacts from remedial activities

| 40 CFR 6.302 and Appendix A] E.O. 11990 Protection of Wetlands

2. Minimize s adverse impact s on areas designated as wetlands. [40 Yes C F R 6.302(a) an d Appendix A]

Clea n Water Act Sectio n 404

3. Regulates the discharge of dredged or fill material into waters of Yes U.S. Consultatio n with the Regional Response Team required.

1 33 USC 1251, et seq; 40 CFR 230, 231; 33 CFR 320-330]

4. Requires federal agencies to avoid, to the extent possible, Yes

adverse impact s associated with destruction or loss of wetlands

Portion s of California Gulch lie within a 100-year

floodplain . If remedial activities are conducted

within the floodplain , thi s regulatio n wil l be

applicable .

Wetlands are present along portion s of California Gulch and the Arkansas River. Regulation s are

applicabl e only i f remedial activitie s impact the

wetlands areas.

Dredge an d fil l substantive requirements wil l appl y

i f Oregon Gulch, Stray Horse Gulch, Malta Gulch, California Gulch (if determined to be "waters of the United States" ) or (he Arkansas River receive fill

material from remedial activities . Wetlands occur along California Gulch an d the Arkansas River; regulation s would be applicabl e

only i f the remedial activitie s impact the wetlands

areas.

EXHIBIT 11

Modifie d From lil' A 1993 Colder Associates
TABLE 4.3

(Continued)

Requirement

Potentiall y Potentiall y Relevant and Applicable Appropriate Comments

Endangered Specie s Act

5. Protect s endangered species and threatened species and

preserves their habitat . Requires coordination with federal

agencies for mitigatio n of impacts. |16 USC 1531 et sequence;

50 CFR 200, 50 CFR 402| Fish an d Wildlife Coordinatio n Ac t

6. Requires coordinatio n with federal and state agencies on

activitie s affecting/modifyin g streams or rivers if the activity has

a negative impact on fish or wildlife . [16 USC 661 et seq.; 40

C F R 6.302(g) j Rivers and Harbors Act of 1899; Section 10

7. Sectio n 10 permi t required for structures or work in or affectin g

navigable waters. [33 USC 403, 33 CFR 320-330] Nationa l Histori c Preservatio n Ac t (NHPA )

8. Requires die preservatio n of historic properties included in or

eligibl e lor the National Register of Historic Places and to

minimize harm to National Historic Landmarks. [ 16 USC 470

et seq.; 40 CFR 6.301(b) ; 36 CFR Part 63, Part 65, Part 800]

T he Histori c and Archeological Data Preservation Act of 1974

9. Establishe s procedures to provide for preservation of historical

a nd archeological data which might be destroyed through

alteratio n of terrain as a result of a federal construction project

or a federall y licensed activit y program. [16 USC 469; 40 CFR

6.30l(c) |

E.G. 11593 Protectio n and Enhancement of the Cultural

Environmen t

1 0. Federal agencies directed to institut e procedures to ensure

programs contribut e to the preservation and enhancement of

n un lederall y owned historic resources. Consultatio n with the Advisor y Counci l on Histori c Preservation required. |16 USC

-170|

Modifie d Fro m FI' A |<W3

Unknown

Y es

No

Y es

Y es

Y es

If there are T/E species or critical habitat s withi n

t he areas impacted by the remedial activities , thi s

regulation would be applicable .

If California Gulch or the Arkansas River an d

adjoinin g streams wil l be impacted by remedial

activities , this regulation would be applicable .

Arkansas River not considered a "navigable river."

Thi s Act i s applicabl e as California Gulch lies

within the Leadville National Histori c Landmark District. A Programmatic Agreement has been

entered into between the EPA , the Advisor y Council

on Histori c Preservation, and the Colorado Slate Historic Preservation Officer in accordance with Sectio n 106 an d 110(0 of NHPA.

Remedial activitie s may affect historical and/or

archeological data at the Superfun d site. A cultural

resources survey was performed to identif y and

evaluate all historic propertie s which may be

affected by remedial activitie s on the mine waste

piles in OU-9.

See #8 above.

Colder Associates
TABL E 4.3

/ (Continued)

Requirement

Potentiall y ApplicablePotentiall y Relevant and Appropriate Comments

T he Archeological Resources Protection Act of 1979

1 1. Requires a permit for any excavation or removal or

archeological resources from public lands or India n lands. [16 D SC 470aa-470ll] T he Histori c Siles Act of 1935

1 2. Enables the National Park Service to preserve historic resources

f or public use. 116 USC 461-467]

Wildernes s Ac t

1 3. Limit s aciivitie s withi n areas designed as wildernes s areas or Nationa l Wildlife Refuge Systems . [16 US C 1311, 16 US C

668; 50 CFR 53, 50 CFR 27] Wild & Scenic Rivers Act

14. Protect s rivers that are designed as wild, scenic, or recreational.

[ 16 USC 1271; 40 CFR 6.302(e.)] Resource Conservation and Recovery Act (RCRA), Subtitle D

1 5. Facilities where treatment , storage, or disposal of solid waste

wil l be conducted must meet certain location standards . These

include locatio n restriction s on proximit y to airports ,

floodplains , wetlands , faul t areas, seismic impact zones, and

unstable areas |40 CFR 258.10-15]. STAT E REGULATION S

Colorado Historical , Prehisiorieal and Archeological Resources Act

1 6. Establishe s procedures and requires a permi t for investigation ,

excavation , gathering, or removal from the natural state of any

historical , prehistorical , or archeological resources on stale

lands for the benefi t of recognized scientifi c or educational

institutions . Also requires an excavation permit and notificatio n

if human remains are foun d on state land. [Colorado Revised Statutes , Title 24, Article 80, Section s 401-411) Register of Histori c Places

1 7. Establishe s requirement s for protectin g propertie s of historical

significance . (Colorado Revised Statutes , Title 24, Articl e 80, Section s I()l-K)8 |

Modified From EPA 1993

No

No

No

No

No

No

Y es

No

No

No

Y es

Unknown

Unknown

Colder Associates

M ay be relevant and appropriate if any remedial

activity involves removal or archeological

resources; substantive requirements need to be met.

M ay be "to be considered" if remedial activitie s

impact areas eligible for inclusion in the National Register of Historic Places.

T he site is not within a federally-owned area

designed as^a wilderness area or a National Wildlife Refuge System.

T he Arkansas River is not listed as a Wild and Scenic River.

Applicabl e i f interim storage, treatment , an d

disposal is conducted as part of the California Gulch

remedial action.

M ay be relevant and appropriate if archeological

resources are removed or human remains discovered

durin g remedial activities; coordinatio n with state

archeologis t required, but no permi t needed for Superfun d site.

M ay be applicabl e if remedial action s impact any

propert y listed on the Register of Histori c Places .
TABLE 4.3

(Continued

Requirement

Potentially Applicable

Potentiall y Relevant and Appropriate Comments

Colorado Nongame , Endangered, or Threatened Specie s Act

(CRS 33-2-103 through 108, 1984)

18. Protect s endangered and threatened species and preserves their

habitats . Requires coordination with the Division of Wildlife if

remedial activitie s impact on slate-listed endangered/threatened

species or their habitat . [Colorado Revised Statutes , Title 33, Articl e 2, Section s 101-1081.

Colorado Specie s of Special Concern and Specie s of Undetermined Statu s

1 9. -Protect s animal s listed on the Colorado Division of Wildlife

generated list . Coordination with the Division of Wildlife is

strongl y urged, if animal species are to be impacted. [Colorado Div. of Wildlife Administrative Directive E-l , 1985, modified ]

Colorado Natural Areas

2 0. The Colorado Natural Areas Program maintains a lis t of plant

species of special concern for the State . Although not protected

by Slate statute , coordination with Division of Parks and Outdoor Recreation is recommended if activities wil l impact

listed species. [Colorado Revised Statutes , Title 33, Article 33, Sectio n 104|

Stale Solid Wast e Disposal Site s an d Facilitie s Act , Colorado Revised Statutes , Title 30, Articl e 20, Section s 101-118.

2 1. Establishe s regulation s for solid waste management facilities ,

includin g location standards . [6 CCR 1007-2)

Unknown

No

No

Y es

If species on the State T/E lis t or their habitat s are

found in areas that will be impacted by remedial

activities , the regulations wil l be applicable . A T/E

survey of the California Gulch site was conducted,

and concluded that there is no evidence that any

listed species inhabit the site.

Unknown If remedial activities impact animal species listed as

special concern or of undetermined status, this

directive would be "to be considered" and

coordination with the Division of Wildlife

recommended, even though there is no statutor y

authority. A survey of potential species of special

concern was conducted as part of the TEE , and

concluded that there is no evidence of animal

species of special concern at the sile.

Unknown If plant s on the lis t of Plan t Specie s of Special Concern are foun d in the areas impacted by

remedial activities , thi s program would be "to be

considered" an d coordination with Colorado' s Division of Parks and Outdoor Recreation would be

necessary. A survey of potential plan t species of

special concern was conducted, and concluded that

there is no evidence of plan t species of special

concern at the site.

Y e s Applicabl e i f remedial activitie s involve Hie disposal

of solid waste materials. Permits are not required

f or onsite activitie s at a site listed on the NPL .

Modified rioi n I-PA 1993 Colder Associates
TABLE 4.3

(Concluded) Potentiall y Potentially Relevant and

_______________Requirement__________________Applicable Appropriate_____________Comments__________

Colorado Wildlife Act '

2 2. Establislle s provisions governing the taking, possession, and use No No Remedial actions being considered wil l not involve

of wildlife and migratory birds. [Colorado Revised Statutes , any taking, possession, or use of wildlife and Tid e 33 , Arlicl e I , Section s 101-120 migratory birds.

Mudilic d l-roi n HI' A IW. l Colder Associates