EPA Superfund
      Record of Decision:
                                 PB98-964401
                                 EPA 541-R98-076
                                 October 1998
       California Gulch OU 3
       Leadville, CO
       5/6/1998

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                  RECORD OF DECISION

                 STOCKPILED FINE SLAG
        ARKANSAS VALLEY SMELTER SLAG PILE
CALIFORNIA GULCH SUPERFUND SITE (OPERABLE UNIT 3)
                 LEADVILLE, COLORADO

                         May 1998
                U.S. Environmental Protection Agency
                    999 18th Street, Suite 500
                    Denver, Colorado 80202

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                               RECORD OF DECISION

                              STOCKPILED FINE SLAG
                     ARKANSAS VALLEY SMELTER SLAG PILE
            CALIFORNIA GULCH SUPERFUND SITE (OPERABLE UNIT 3)
                              LEADVILLE, COLORADO

 The U.S. Environmental Protection Agency (EPA), with the concurrence of the Colorado
 Department of Public Health and Environment (CDPHE), presents this Record of Decision
 (ROD) for stockpiled fine slag at the Arkansas Valley smelter slag pile of Operable Unit 3 (OU
 3) within the California Gulch Superfund Site in Leadville, Colorado. The ROD is based on the
 Administrative Record for California Gulch OU3, including the Remedial Investigation/
 Feasibility Study (RJ/FS), the Proposed Plan, and the public comments received. The ROD
 presents a brief summary of the RJ/FS, actual and potential risks to human health and the
 environment, and the Selected Remedy.  EPA followed the Comprehensive Environmental
 Response, Compensation, and Liability Act, as amended, the National Contingency Plan (NCP),
 and appropriate guidance in preparation of the ROD.  The three purposes of the ROD are to:

       1.      Certify that the remedy selection process was carried out in accordance with the
              requirements of the Comprehensive Environmental Response, Compensation, and
              Liability Act, 42 U.S.C. 9601 et seq., as amended by the Superfund Amendments
              and Reaulhorization Act (collectively, CERCLA), and, to the extent practicable,
              the NCP;

       2.      Outline the engineering components and remediation requirements of the Selected
              Remedy; and

       3.      Provide the public with a consolidated source of information about the history,
              characteristics, and risk posed by the conditions of the stockpiled fine slag at the
              Arkansas Valley Smelter slag pile of OU 3, as well as a summary of the cleanup
              alternatives considered, their evaluation, the rationale behind the Selected
              Remedy, and the agencies' consideration of, and responses to, the comments
              received.

The ROD is typically organized into the following three distinct sections:

       1.      The Declaration section functions as an abstract for the key information
              contained in the ROD and is the section of the ROD signed by the EPA Acting
              Regional Administrator and the CDPHE Director;

       2.      The Decision Summary section provides an overview of the OU 3 characteristics,
              the alternatives evaluated, and the analysis of those options. The  Decision
              Summary also identifies the Selected Remedy and explains how the remedy
              fulfills statutory requirements; and

Record of Decision
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       3.      The Responsiveness Summary section addresses public comments received on
               the Proposed Plan, and other information in the Administrative Record.  However,
               since the EPA did not receive any written public comments, this ROD will not
               contain a Responsiveness Summary.
Record of Decision
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                                               DECLARATION
Record or Decision
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                                   DECLARATION

SITE NAME AND LOCATION

Stockpiled Fine Slag
Arkansas Valley Smelter Slag Pile
California Gulch Superfund Site (Operable Unit 3)
Leadville, Colorado

STATEMENT OF BASIS AND PURPOSE

This decision document presents the Selected Remedy for stockpiled fine slag at the Arkansas
Valley smelter slag pile of Operable Unit 3 within the California Gulch Superfund Site in
Leadville, Colorado.  EPA, with the concurrence of CDPHE, selected the remedy in accordance
with CERCLA and the NCP. Note that this decision addresses stockpiled fine slag only. Other
activities required for OU3, including other slag piles, the railroad easement, and the railroad
yard, are addressed under a Consent Decree with the  Denver & Rio Grande Western Railroad.

This decision is based on the Administrative Record  for the stockpiled fine slag at the Arkansas
Valley smelter slag pile of OU 3 within the California Gulch Superfund Site.  The
Administrative Record (on microfilm) and copies of key documents are available for review at
the Lake County  Public Library, located at 1115 Harrison Avenue in Leadville,  Colorado, and at
the Colorado Mountain College Library, in Leadville, Colorado. The complete  Administrative
Record may also be reviewed at the EPA Superfund Records Center, located at 999 18th Street.
5th Floor, North Terrace in Denver, Colorado.

ASSESSMENT OF THE SITE

The stockpiled fine slag at the Arkansas Valley smelter slag pile does not present an imminent or
substantial endangerment to public health, welfare, or the environment.

DESCRIPTION OF THE SELECTED REMEDY

The Selected Remedy is the No Action Alternative, which was presented in the Final Stockpiled
Fine Slag Feasibility Study Report (FS) (Terranext, 1996a). The FS used a comparative analysis
to evaluate several alternatives and identify the advantages and disadvantages of each.  Selection
of the No Action Alternative was based on this analysis.  For the stockpiled fine slag, the
Selected Remedy leaves the  slag piles in their existing condition with no  remediation,
engineering controls, long term maintenance, or clean up  planned. The Selected Remedy is
protective of human health and the environment, and is considered effective because 1) no
complete human or ecological exposure pathways were identified for the  stockpiled fine slag and
2) the potential for release of metals in leachate from the stockpiled fine slag is minimal.

The Selected Remedy provides a contingency for resource utilization, which may be undertaken
in the future if regional market demand exists for the material. Resource  utilization involves the
Record of Decision
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use or reuse of the slag material as a commerciaJ product. Due to concerns about the potential
for release of airborne particulates if resource utilization is undertaken, the EPA has determined
that resource utilization of the stockpiled fine slag is only appropriate if it is encapsulated for
reuse. Encapsulation can include the use of fine slag in concrete or asphaJt aggregate; or as road
base, backfill or other construction material as long as the fine slag is chemically bound or
physically separated from any exposure scenario by a barrier consisting of another material.
Dust suppressants to control paniculate emissions and best management practices to control
stormwater runoff would also be employed to contain contaminant releases from the fine slag
stockpile and during implementation of the contingency remedy. Resource utilization must also
take into consideration any toxic leaching potential for the fine slag.

DECLARATION STATEMENT

No remedial action is necessary to ensure protection of human health and the environment.
Max H. Dodson                                              Date
Assistant Regional Administrator
Ecosystems Protection and Remediation
U.S. Environmental Protection Agency, Region VIII
Record of Decision
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                                            DECISION SUMMARY
Record of Decision
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                         TABLE OF CONTENTS


 LIST OF FIGURES	DS-iii

 LIST OF TABLES	DS-iv

 LIST OF ACRONYMS AND ABBREVIATIONS	 DS-v

 1.0   SITE NAME, LOCATION, AND DESCRIPTION 	 DS-1

 2.0   OPERABLE UNIT HISTORY AND ENFORCEMENT ACTIVITIES	 DS-3

 3.0   HIGHLIGHTS OF COMMUNITY PARTICIPATION 	 DS-5

 4.0   SCOPE AND ROLE OF OPERABLE UNIT	,	 DS-7

 5.0   SUMMARY OF SITE CHARACTERISTICS 	 DS-9

 6.0   SUMMARY OF SITE RISKS	  DS-13
      6.1    RESIDENTIAL EXPOSURE TO SLAG  	  DS-13
      6.2    RESIDENTIAL EXPOSURE TO IMPACTED GROUND WATER	  DS-14
      6.3    RECREATIONAL USER EXPOSURE TO SLAG	  DS-14
      6.4    WORKER EXPOSURE TO SLAG	  DS-14
      6.5    ENVIRONMENTAL EXPOSURE TO SLAG	  DS-15
           6.5.1  AQUATIC EXPOSURE 	  DS-15
           6.5.2  TERRESTRIAL EXPOSURE	  DS-15

 7.0   DESCRIPTION OF ALTERNATIVES 	  DS-16

 8.0   SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES	  DS-18
      8.1    EVALUATION AND COMPARISON CRITERIA	  DS-18
           8.1.1  THRESHOLD CRITERIA 	  DS-18
           8.1.2  PRIMARY BALANCING CRITERIA	  DS-18
           8.1.3  MODIFYING CRITERIA	  DS-18
      8.2    EVALUATING THE STOCKPILED FINE SLAG ALTERNATIVES ...  DS-19
           8.2.1  OVERALL PROTECTION OF HUMAN HEALTH AND THE
                ENVIRONMENT 	  DS-19
           8.2.2  COMPLIANCE WITH APPLICABLE OR RELEVANT AND
                APPROPRIATE REQUIREMENTS (ARARs)  	  DS-19
           8.2.3  LONG-TERM EFFECTIVENESS AND PERMANENCE 	  DS-19
           8.2.4  REDUCTION OF TOXICITY, MOBILITY, OR VOLUME
                THROUGH TREATMENT	  DS-20
           8.2.5  SHORT-TERM EFFECTIVENESS 	  DS-20
           8.2.6  IMPLEMENTABILITY 	  DS-21
RecordoT Decision
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           8.2.7  COST	  DS-21
           8.2.8  STATE ACCEPTANCE 	  DS-22
           8.2.9  COMMUNITY ACCEPTANCE	  DS-22
           8.2.10 SUMMARY	  DS-22

 9.0   SELECTED REMEDY	  DS-24

 10.0   STATUTORY DETERMINATIONS	  DS-25
      10.1   PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT . ..  DS-25
      10.2   .COMPLIANCE WITH ARARs  	  DS-26
      10.3   COST EFFECTIVENESS	  DS-26
      10.4   UTILIZATION OF PERMANENT SOLUTIONS AND ALTERNATIVE
           TREATMENT TECHNOLOGIES (OR RESOURCE RECOVERY
           TECHNOLOGIES) TO THE MAXIMUM EXTENT POSSIBLE	  DS-26
      10.5 .  PREFERENCE FOR TREATMENT AS A PRINCIPAL ELEMENT	  DS-26

 11.0   DOCUMENTATION OF SIGNIFICANT CHANGES 	  DS-27

 12.0   REFERENCES . ,	  DS-28

 APPENDIX A

      ARARs	  DS-30
Record of Decision
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                                    LIST OF FIGURES

 FIGURE

 Figure 1       General Location Map, California Gulch Superfund Site

 Figure 2       California Gulch Superfund Site and Operable Units.

 Figure 3       Arkansas Valley Slag Pile Current Surface Areas, Volumes, and Angles of
               Repose

 Figure 4       Arkansas Valley Slag Pile Sample Locations and Reconnaissance Information
Record of Decision
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                                     LIST OF TABLES

 TABLE

 Table 1        Estimates of Costs for Remedial Alternatives

 Table 2        Grid Comparison Method for Alternatives Analysis
Record of Decision
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                    LIST OF ACRONYMS AND ABBREVIATIONS

 AMSL       Above Mean Sea Level
 AOC         Administrative Order of Consent
 ARAR       Applicable or Relevant and Appropriate Requirements
 AV          Arkansas Valley
 BMP         Best Management Practices
 CDPHE      Colorado Department of Public Health and Environment
 CERCLA     Comprehensive Environmental Response, Compensation and Liability Act
 CFR         Code of Federal Regulations
 D&RGW     Denver and Rio Grande Western Railroad
 EPA      '   U.S. Environmental Protection Agency
 FS           Final Stockpiled Fine Slag Feasibility Study
 mg/kg        milligram per kilogram
 mph          miles per hour
 NCP         National Oil and Hazardous Substances Pollution Contingency Plan
 NPL         National Priorities List
 OU          Operable Unit
 ppm          parts per million
 PRPs         Potentially Responsible Parties
 RI/FS         Remedial Investigation/Feasibility Study
 ROD         Record of Decision
 SFS          Screening Feasibility Study
 SPLP         Synthetic Precipitation Leaching Procedure
Record of Decision
Stockpiled Fine Slay (OU 3)
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DS-v

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                  1.0  SITE NAME, LOCATION, AND DESCRIPTION

 Stockpiled Fine Slag
 Arkansas Valley Smelter Slag Pile
 California Gulch Superfund Site (Operable Unit 3)
 Leadville, Colorado

 The California Gulch Superfund Site is located in Lake County, Colorado, in the upper Arkansas
 River basin, approximately 100 miles southwest of Denver (see Figure 1). The Site encompasses
 approximately 16.5 square miles and includes the towns of Leadville and Stringtown, a portion
 of the Leadville Historic Mining District, and the portion of the Arkansas River from its
 confluence with California Gulch downstream to the Lake Fork Creek confluence.  The
 California Gulch Superfund Site has been organized into 12 operable units (OUs).  Figure 2
 shows the Site boundaries and the location of OU 3.

 Operable Unit 3 (Figure 2) includes three slag piles (Arkansas Valley, La Plata, and Harrison St.)
 owned by Denver and Rio Grande Western Railroad (D&RGW), a railyard right-of-way through
 Leadville and a railyard in the area of Leadville known as Poverty Flats. This Record of
 Decision (ROD) addresses only the fine slag1 stockpiled as a subpile of the Arkansas Valley
 (AV) Smelter Slag Pile. In addition, D&RGW has identified a small volume of fine slag in the
 railyard (Poverty Flats). D&RGW has prepared a plan which addresses removal of the fine slag
 from this area to the AV Smelter Slag Pile (EPA, 1996).

 The AV  Smelter Slag Pile is the largest and westernmost of the three slag piles owned by
 D&RGW in the Leadville area (Figure 2). This pile was generated from slag produced primarily
 by the AV smelter facility, which operated from 1882 to 1960.  The pile covers approximately 40
 acres and is approximately 9,800 feet above mean sea level (AMSL). Based upon aerial
 photography, the pile volume in the late 1950s was approximately 1.2 million cubic yards.
 Today, approximately 422,000 cubic yards of slag remain on the AV Smelter Slag Pile. The
 volume of stockpiled fine slag at the AV Smelter Slag Pile is approximately  190,000 cubic yards.
 The slag pile was purchased by D&RGW from ASARCO in 1961 for use as  ballast (Terranext,
 1996a).

 The AV  Smelter Slag Pile is bounded by Leadville Sewage Treatment Plant property and State
 Highway 24 to the south, old smelter works to the north, wooded property to the west, and other
 smelter-related wastes and Stringtown to the  east.  California Gulch runs adjacent to the slag pile
 vicinity for approximately 1/5 its length.  D&RGW has performed work near the California
 Gulch to minimize the direct contact of surface water with the slag piles.  In the vicinity of the
 AV Smelter Slag Pile, clean fill has been bermed along the toe of the slag to  prevent direct
 surface water from contacting the slag (Terranext, 1996a).
       'Fine slag is sorted slag which is less than 3/8 inch. Sorted slag is slag that has been physically separated
into size fractions for the purpose of railroad ballast production (Terranext, I996a).

Record of Decision
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 Lake County is relatively small (380 square miles) and is predominately rural, with a 1990
 population of 6,007 (U.S. Department of Commerce, 1990). About half of this population
 resides within the City of Leadville.  The population of Lake County has fluctuated with the
 mining industry-. The population increased to about 9,000 between 1960 and 1981 and then
 declined throughout the 1980's. Land surrounding OU3 is predominately dedicated to mining,
 commercial, and residential uses.

 The climate of Lake County is dry but otherwise typical of most alpine regions in the southern
 Rocky Mountains. The average annual maximum temperature in the Leadville area is 50.5
 degrees Fahrenheit and the average annual minimum temperature is 21.9 degrees Fahrenheit,
 with an annual mean temperature of 37.3 degrees Fahrenheit. The south-central portion of the
 county, at an elevation near 9,000 feet AMSL, receives about 10 inches of precipitation annually.
 Wind is predominantly from the northwest, with speeds typically from 0 to 30 miles per hour
 (mph) (WCC, 1993). Populated areas of Leadville are predominantly upwind of the AV Smelter
 Slag Pile.
Record of Decision
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         2.0  OPERABLE UNIT HISTORY AND ENFORCEMENT ACTIVITIES

 The California Gulch Superfund Site is located in the highly mineralized Colorado Mineral Belt
 of the Rocky Mountains.  Mining, mineral processing, and smelting activities have produced
 gold, silver, lead, and zinc for more than 130 years in the Leadville area. Mining and its related
 industries continue to be a source of income for both Leadville and Lake County. The Leadville
 Historic Mining District includes an extensive network of underground mine workings in a
 mineralized area of approximately 8 square miles located around Breece Hill. Mining in the
 District began in 1860, when placer gold was discovered in California Gulch. As the placer
 deposits were exhausted, underground workings became the principle method for removing gold,
 silver, lead, and zinc ore.  As these mines were developed, waste rock was excavated along with
 the ore and'placed near the mine entrances. Ore was crushed and separated into metallic
 concentrates at mills, with mill tailing generally slurried into tailing impoundments.

 Approximately 17 smelter facilities are reported to have once operated within the Site.  Most
 operations ceased by about 1900, although some facilities continued to operate into the 1960's.
 At present, nearly all of the mines within the Site boundaries are inactive; only a few small-to-
 moderate-sized mining operations exist. All of the mills and smelters which  operated onsite are
 inactive and/or demolished.

 Due to historic mining, milling, and smelting operations, the Site contains many tailings
'impoundments, fluvial deposits, slag piles, waste rock piles, and mine water drainage tunnels.
 Slag on the Site is the mineralized waste byproduct of smelting, and results from the  processing
 of lead ore in high temperature furnaces.  Three major slag piles and several smaller piles remain
 at the Site (Figure 2). In 1961. D&RGW purchased the AV Smelter Slag Pile from ASARCO for
 use as railroad ballast. D&RGW purchased the La Plata slag pile from the Leadville  Sanitation
 District in  1970.  Additionally, D&RGW purchased the Harrison Street Slag  Pile from NL
 Industries in 1983 (EPA, 1996).

 The California Gulch Site was placed on the National Priorities List (NPL) in 1983, under the
 authority of the Comprehensive Environmental Response, Compensation, and Liability Act
 (CERCLA) of 1980. The Site was placed on the NPL because of concerns about the  impact of
 mine drainage on surface waters in the California Gulch and the impact of heavy metals loading
 into the Arkansas River (EPA, 1996).  Several subsequent investigations were conducted within
 the California Gulch Superfund Site that have addressed the slag at the three D&RGW-owned
 piles.

 In 1986, the EPA's contractor, CH2M Hill, sampled surface water, groundwater, and numerous
mine waste piles, and three D&RGW slag piles as part of the California Gulch Site Remedial
Investigation (RI) (EPA, 1989). The objective of the mine waste and slag sampling was to better
characterize the materials in the California Gulch Superfund Site. This was the first time that the
EPA had sampled slag at the Site.

In 1988, James P. Walsh and Associates, Inc. conducted a Soils Investigation. The stated
objectives of this study were to define potential action levels for soil, determine background
Record of Decision
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 metals content of soils, delineate the extent of soil contamination, and determine sources of soil
 contamination.  This study was initiated by ASARCO, another potentially responsible party
 (PRP) at the Site. Three samples of slag were collected as part of this study: one from the
 Harrison Street pile, one from the La Plata pile, and one from an area west of Leadville.  This
 study did not include the AV Smelter Slag Pile (MK, 1992).

 In May 1989, Jacobs Engineering performed a second sampling of slag for the EPA. The
 purpose of the study was to determine the concentrations of metals in the three D&RGW slag
 piles and to evaluate the potential for migration of these metals to soil, water or air. Potential
 hazards to the environment and public health from the slag in Leadville were evaluated.

 On December 3,  1991, EPA and D&RGW entered into an Administrative Order on Consent
 (AOC), CERCLA - VIII - 92006, for the performance of a remedial investigation/feasibility
 study (RI/FS) of the lead slag piles. Prior to the AOC, EPA had studied the slag piles as part of
 other investigations at the Site. In  1992, D&RGW performed an RI (MK, 1992) that addressed
 seven lead slag piles, including the Arkansas Valley, Harrison, and La Plata slag piles, and one
 zinc slag pile. Following the RI, a Site-Wide  Screening Feasibility Study (SFS) was undertaken
 as a joint effort between the PRPs and EPA.  The SFS was completed in March 1993. It
 screened several remediation alternatives for all types of slag located at the AV Smelter Slag  Pile
 based on specific criteria, such as relative cost, implementability, and effectiveness. The three
 alternatives retained for further evaluation were: no action, institutional controls, and resource
 utilization  (EPA, 1996).

 On December 15, 1993, D&RGW entered into a Consent Decree with  EPA to perform the
 remainder  of their site work. The Consent Decree stated EPA's concerns regarding the fine
 fraction of the stockpiled slag and the potential for particulate release during ballast operations as
 a potential human health exposure pathway. The Consent Decree required D&RGW to perform
 a feasibility study for stockpiled fine slag and  to submit an operations plan before initiating any
 ballast operations. In July of 1995, D&RGW  submitted a ballast operations plan to EPA.
 Following  EPA's approval of the plan, ballast operations commenced in August 1995 (EPA,
 1996).

 In May of  1996, D&RGW submitted a feasibility .study for the stockpiled fine slag (the FS) at the
 AV Smelter Slag Pile, according to the terms of the Consent Decree. The existing fine slag
 subpile and fine slag potentially generated from future ballast production were the focus of the
 FS. The FS provided a detailed analysis of the three retained remediation alternatives from the
 SFS as applied to the stockpiled fine slag. The result of the Feasibility Study for the stockpiled
 fine slag was a Proposed No Action Plan for the stockpiled fine slag as a subpile of the AV
 Smelter Slag Pile (EPA, 1996).
Record of Decision
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                 3.0  HIGHLIGHTS OF COMMUNITY PARTICIPATION

 Public participation is required by CERCLA Sections 113 and 117.  These sections require that
 before adoption of any plan for remedial action to be undertaken by  EPA. the State, or an
 individual (PRP), the lead agency shall:

        1.      Publish a notice and brief analysis of the Proposed Plan and make such plan
               available to the public; and

        2.      Provide a reasonable opportunity for submission of written and oral comments
               and an opportunity for a public meeting at or near the Site regarding the Proposed
               Plan and any proposed findings relating the cleanup standards.  The lead agency
               shall keep a transcript of the meeting and make such transcript available to the
               public.  The notice and analysis published under item # 1 above shall include
               sufficient information to provide a reasonable explanation of the Proposed Plan
               and alternative proposals considered.

 Additionally,-notice of the final remedial action plan set forth in the  ROD must be published, and
 the plan must be made available to the public before commencing any remedial action. Such a
 final plan must be accompanied by a discussion of any significant changes to the preferred
 remedy presented in the Proposed Plan along with the reasons for the changes.  A response
 (Responsiveness Summary) to each of the significant comments, criticisms, and new data
 submitted in written or oral presentations during the public comment period must be included
 with the ROD.

' EPA has conducted the required community participation activities through presentation of the
 RJ/FS and Proposed Plan, a 30-day public comment period, a formal public hearing, and
 presentation of the Selected Remedy in this ROD. However, since the EPA did not receive any
 written public comments on the Proposed No Action Plan for the Stockpiled Fine Slag, this ROD
 does not contain a Responsiveness Summary.

 The Proposed No Action Plan for Stockpiled Fine Slag at the AV Smelter Slag Pile was released
 for public comment on September 27, 1996.  The RJ/FS and the Proposed No Action Plan were
 made available to the public in the Administrative Record located at  the EPA Superfund Records
 Center in Denver and  the Lake County Public Library in Leadville.  A formal public comment
 period was designated from September 27, through October 28,  1996.

 On October 3,  1996, the EPA hosted a public meeting to present the  Proposed Plan for
 Stockpiled Fine Slag at OU 3 of the California Gulch Superfund Site. The meeting was held at
 7:00 pm in the  Mining Hall of Fame in Leadville, Colorado.  Representatives from the EPA and
 D&RGW presented the Proposed Plan.  Three alternatives were discussed: No Action,
 Institutional Controls, and Resource Utilization.  The No Action alternative was presented as
 EPA's and D&RGW's preferred alternative.  A portion of the hearing was dedicated to accepting
 formal oral comments from the public. Only two questions were raised during this public
 Record of Decision
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 meeting. These questions were in regard to the volume of the fine slag proposed for No Action
 and the nature of the soil beneath the Harrison St. slag pile, which is not relevant to this ROD.
Record of Decision
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                     4.0 SCOPE AND ROLE OF OPERABLE UNIT

 The California Gulch NPL Site covers a wide area (Figure 2). EPA has established the following
 OUs for the cleanup of geographically-based areas within the Site.  The OUs are designated as:

        OU1   Yak Tunnel/Water Treatment Plant
        OU2  Malta Gulch Fluvial Tailing/Leadville Corporation Mill/Malta Gulch Tailings
              Impoundments
        OU3   D&RGW Slag Piles/Railroad Easement/Railroad Yard and Stockpiled Fine Slag
        OU4  Upper California Gulch
        OUS   ASARCO Smelter/Slag/Mill Sites
        OU6   Starr Ditch/Penrose Dump/Stray Horse Gulch/Evans Gulch
        OU7   Apache Tailing Impoundments
        OUS   Lower California Gulch
        OU9  Residential Populated Areas
        OU10 Oregon Gulch
        OU 11  Arkansas River Valley Floodplain
        OU12 Site Water Quality

 The purpose of the D&RGW Slag Piles/Railroad Easement/Railroad Yard OU RI/FS was to
 gather sufficient information to support an informed risk management decision on which
 remedies are the most appropriate for the D&RGW Stockpiled Fine Slag portion of OU3. The
 RJ/FS was performed in accordance with the National Oil and Hazardous Substances Pollution
 Contingency Plan (NCP), 40 Code of Federal Regulations (CFR) Part 300, and CERCLA
 Section 104, 42 U.S.C. § 9604.

 The objectives of the RJ/FS were to:

 •       Determine the nature and extent of metals in source areas and other affected areas within
       the D&RGW Slag Piles/Railroad Easement/Railroad Yard OU;

 •      Define the potential pathways along which metals can migrate, as well  as the physical
       processes and, to the extent necessary, the chemical processes that control these
       pathways;

 •      Determine risk assessment information including potential receptors, exposure patterns,
       and food chain relationships; and

 •      Develop, screen, and evaluate remedial alternatives and predict the consequences of each
       remedy.

Based on the findings of previous investigations and the results of the D&RGW Slag
Piles/Railroad Easement/Railroad Yard OU RI/FS, the sources and  areas of environmental
contamination at the Stockpiled Fine Slag (AV Smelter Slag Pile) portion of OU3 have been
adequately delineated.
Record of Decision
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5i:9SP.vJ280-OM'FINALROD'.OU3ROD2.WPD

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 The remedy outlined in this ROD represents the final remedial action only for the stockpiled fine
 slag at the AV Smelter Slag Pile. Remedial actions undertaken at the Stockpiled Fine Slag
 portion of OU3 are intended to be consistent with the remedial action objectives and goals
 identified for the California Gulch NPL Site and other OU investigations.
Record of Decision
Stockpiled Fine Sby (OU 3)
5I298P.VI280-OI4 FISALROIJ'.OU3ROD2.WPD

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                     5.0 SUMMARY OF SITE CHARACTERISTICS
 As a result of D&RGW processing the slag for use as railroad track ballast, the AV Smelter Slag
 Pile is actually composed of several sub-piles (Figure 3).  The subpiles of the AV Smelter Slag
 Pile site include sorted fines, water-quenched fines, ballast-sized material, oversized material,
 and unsorted air-cooled slag. The subpiles of sorted fines consist of the less than 3/8 inch
 diameter slag.  The ballast-sized subpile is composed of material with particle sizes ranging from
 approximately 3/8 inch to 2-1/2 inches in diameter. Two subpiles of oversized material from
 ballast processing consist of slag that is greater than 2-1/2 inches in diameter, some brick, and
 some scrap iron.  The existing fines piles and fines potentially generated from future ballast
 production are the focus of this ROD. Figure 3 also depicts the location of stockpiled fine slag at
 the AV Smelter Slag Pile. This and a small amount of fine slag in the railyard are  the only
 locations within the California Gulch Superfund Site with stockpiled fine slag.  The volume of
 stockpiled fine slag at the AV Smelter Slag Pile is approximately 190,000 cubic yards. The
 volume of stockpiled fine slag at the railyard was estimated at approximately 220 cubic yards
 (Terranext, 1996b). As noted previously, the small amount of fine slag at the railyard has been
 moved to the AV Smelter Slag Pile. The total volume of fine slag moved from the railyard to the
 AV Smelter Slag Pile was approximately 1200 cubic yards.

 The following paragraphs discuss the primary contaminants of concern, summarize the nature
 and extent of contamination, and provide a brief description of contaminant fate and transport.

 Site Characterization Summary - Stockpiled Fine Slag

" During the Lead Slag Pile RJ (MK, 1992) a total of 18 slag samples were collected from the AV
 Smelter Slag Pile (Figure 4). Four of these samples were collected from the sorted fines and four
 from the water-quenched fines subpiles. These samples were collected from the surface to a
 depth of 3 feet. In addition, four subslag samples were collected from four coreholes drilled at
 the AV Smelter Slag Pile. Two of these subslag samples were collected  from directly below the
 water-quenched fines subpile.  Each sample was submitted for laboratory compositional and
 leachability analysis. Material from the finer-grained slag piles was also submitted for particle
 size testing. Compositional analyses included total metals, water-soluble anions, and acid-base
 accounting. Leachability testing included Synthetic Precipitation Leaching Procedure (SPLP)
 (EPA Method 1312) and column leach tests, which were intended to simulate, as closely as
 possible, in situ conditions (Terranext, 1996a).

 Compositional  results showed that the slag is an iron magnesium silicate, with residual base
 metals.  Concentration means for the four primary metals of concern collected from fine slag
 sample locations at the Site are as follows:

       •       Arsenic means; 435 milligram per kilogram (mg/kg) -sorted fines, 909 mg/kg
              water quenched fines
       •       Cadmium means; 11.9 mg/kg-sorted fines,  16.6 mg/kg water-quenched fines
Record of Decision
Stockpiled Fine Slag (OU .1)
5I29SP.J:80-OI4\FINALROD.OU3ROD2.WPD

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        •      Lead means; 10,800 mg/kg-sorted fines, 9,650 mg/kg water-quenched fines
        •      Zinc means; 44,000 mg/kg-sorted fines, 73,000 mg/kg water-quenched fines

 Compositional results for the two subslag soil samples (AVB103 and ABV104) collected
 beneath the water-quenched fines showed concentrations of metals of concern to be significantly
 lower than those for the slag material, and within the range of literature values for metals
 occurring naturally in soil (MK, 1992-Table 4-15). These samples showed the lowest value for
 arsenic (5.7 mg/kg), lead (84.8 mg/kg) and for zinc (188 mg/kg) from all subslag soil samples
 collected. Site-specific background has not been established, however, ranges for metals of
 concern in Colorado soils are as follows: arsenic (1.2-24 mg/kg), lead 15-150 mg/kg) and zinc
 (16-300 mg/kg) (Terranext, 1996a). The subslag soil samples collected from beneath the water-
 quenched fine slag at AV exhibited a negative acid-forming potential.

 Leaching analysis, which included both SPLP and column leach studies, showed minimal
 leaching of metals of concern. Synthetic Precipitation Leaching Procedure results for all
 elements tested in slag were below the toxicity characteristic criteria, listed in 40 CFR 261.24.
 Mean values for the contaminants of concern were generally two orders of magnitude lower than
 these regulatory thresholds. Column leach tests showed similar low levels of leaching
 (Terranext, 1996a).

 Particle size data and site-specific meteorological data were used to determine whether slag .in
 the fine-grained piles has the abHity to become airborne. Threshold friction velocities (the wind
 speed above which the surface material becomes airborne) were calculated using the mode of the
 aggregate size distribution. Wind data and the height of the piles were used to calculate the
 friction velocity.  Results for the two fines piles  are:

       Threshold Friction Velocity
              sorted fines                1.0 meters per second (m/sec)
              water-quenched fines        0.58 m/sec
       Friction Velocity                  0.55 m/sec

 A friction velocity lower than the threshold  friction velocity demonstrates that sustained wind
 gusts (0.55 m/sec, MK 1992) in Leadville are not fast enough to  cause wind erosion of the fines
 slag piles.

 Groundwater

 A site-wide monitoring program will be developed at the California Gulch Superfund Site once
 all source areas have been addressed.  Groundwater in the vicinity of the stockpiled fine slag has
not been fully characterized. As noted above, the subslag material showed concentrations of
metals of concern to be significantly lower than  those for the slag material, and within the range
of literature values for metals occurring naturally in soils. These results suggest that surface
water infiltration through the slag piles does not significantly impact groundwater nor does it
impact the soils beneath the slag piles, as evidenced by the results of the soil analyses (Terranext,
 I996a).
Record of Decision
Stockpiled Fine SI.11; (OU .1)                           _ c  ,,
 SI29SI>:U280-ON.FINAI,ROD OU3ROD2.WPD               UO~ I (J

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 Surface Water

 No discreet conveyances of surface water runoff from the AV area have been noted.
 Additionally, the berm placed along the California Gulch is designed to eliminate surface water
 runoff from directly entering the California Gulch (Terranext, 1996a).

 Soils

 Analysis of subslag soils from beneath the fine slag piles show the lowest concentration for lead,
 arsenic and zinc of any of the subslag samples collected (Terranext, 1996a).

 Discussion of Fate and Transport

 Existing pathways for potential migration of metals of concern include wind, leaching, mixing by
 human activities, runoff, and direct contact.

 Release Mechanism 1 - Wind

 The air pathway analysis results indicate that wind erosion is not a viable release mechanism for
 the lead slag piles, including  the AV water-quenched and sorted fines piles.

 Release Mechanism 2 - Leaching

 Testing in subslag material does not indicate that leachate from slag contributes to elevated
 metals concentrations in the vadose zone beneath the slag piles. This conclusion is supported by
 the lack of acid-generating potential and the  neutral-to-basic pH of the slag and subslag
 materials.

 Release Mechanism 3 - Mixing bv Human Activities

 Transport of slag by human activities has occurred, as it was historically used for road
 maintenance within the Site by Lake County and the Colorado Department of Transportation.
 This mechanism will not continue in the future as reuse of the slag material is controlled as
 specified in this ROD.

 Release Mechanism 4 - Surface Water Runoff

No evidence of transport of slag fines  by surface water runoff was observed at any of the
 examined piles. Slag does not appear to be transported from piles onto adjacent soils in rivulets
or channels.  Pile integrity, especially  for fines piles where this is most critical, appears intact.
This potential release mechanism for slag is  not a concern at the AV Smelter Slag Pile.
Record of Decision
Siockpilcd Fine Slas (OU J)
5i:98P:'J280-OM'.FINALROD'.OU3ROD2.\VTO

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 Release Mechanism 5 - Direct Contact

 Due to the physical characteristics of the slag piles, direct contact with the slag piles was
 considered unlikely in EPA's Preliminary Baseline Human Health Risk Assessment (EPA 1991).
 Therefore, it was eliminated as a release mechanism.
Record of Decision
Siockpiled Fine Slag 
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                            6.0 SUMMARY OF SITE RISKS

 In the Preliminary Baseline Human Health Risk Assessment (EPA, 1991) lead and arsenic were
 identified as the primary chemicals of potential concern at the California Gulch NPL Site.  Since
 the completion of the preliminary risk assessment, several important studies were completed that
 provided more extensive and more reliable data on environmental concentrations and on human
 and ecological exposures. Leadville officials and business leaders expressed concern over
 possible risks and liabilities associated with commercial and recreational uses within the Site.
 Therefore, in the final baseline risk assessment, risks posed by environmental contamination to
 current or future workers in the commercial and business district of the community and to people
 who engage in recreational activities in and around the community were evaluated.  The
 assessment was conducted to determine if environmental contamination was of concern at any
 locations presently zoned commercial/industrial and to address concerns regarding the
 development of a proposed bike path around the community (EPA. 1996).

 In 1995, EPA completed two parts of the Baseline Human Health Risk Assessments for the
 California Gulch Superfund Site. These are: Part A Risks to Residents from Lead (EPA,
 1995b), and Pan C Evaluation of Recreational, Worker Scenarios (EPA,  1995c). Part A
 evaluates risks to residents from lead; and Part C evaluates risks to workers in the commercial
 and business district and to recreational users in areas in and around the community. The
 following paragraphs summarize results of the final baseline risk assessment as they relate to the
 stockpiled fine slag at the AV Smelter Slag Pile.

 Terrestrial and aquatic risks associated with exposure to site chemicals were also evaluated by
 EPA.  Aquatic risks were evaluated in the Final Baseline Aquatic Ecological Risk Assessment
 (EPA, 1995d) and terrestrial risks were evaluated in the Ecological Risk Assessment for the
 Terrestrial Ecosystem (EPA, 1997).

 6.1    RESIDENTIAL EXPOSURE TO SLAG

 The evaluation of exposure to contaminants at waste piles included consideration of slag pile
 data, with an exposure scenario conservatively evaluating a child playing on the waste piles who
 may come in contact with contaminants through inadvertent ingestion or dermal (skin) contact.
 The dermal  contact pathway was determined to be minimal and was not considered further.  The
 residential risk assessment also determined  that non-lead metals in most waste piles pose either
 no risk or only low risk from direct contact  while playing on the piles. For the evaluation of lead
 exposure at the waste piles, the data were found to be too limited to derive reliable estimates of
 the potential impact of direct exposures to children who play on waste piles. Therefore a
 quantitative evaluation was not performed.  As stated in the preliminary risk assessment and the
 SFS, direct contact of residents with the slag piles is not expected to occur.

 Wind erosion and direct contact were not considered viable release mechanisms for the
 stockpiled fine slag.  However, based on the results of the risk assessment, there is some concern
about the potential for paniculate release and human exposure should resource utilization of the
stockpiled fine slag be undertaken. For example, inhalation of slag particles could occur if the
Record of Decision
Stockpiled Fine Slay (OU 3)                          nc . ^
 5I298P:V3280-OM'.FINA1.ROD-.OU3ROD2 WPD               U^~ ' ->

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 material is disturbed from its current state. If the resource utilization option is exercised,
 measures would be required to prevent contaminant releases.

 6.2    RESIDENTIAL EXPOSURE TO IMPACTED GROUNDWATER

 The remedial action objective in the 1993 SFS was to prevent leaching of metals of concern in
 concentrations that would have an adverse impact on soils, surface water, or groundwater in the
 area near the slag piles.  The 1996 FS determined that testing of material under the slag pile did
 not indicate that migration of contaminants by leaching from the slag contributes to elevated
 metals beneath the slag piles. In addition, the final baseline risk assessment determined that
 groundwater from this aquifer is not currently used for drinking, and it is relatively unlikely that
 it will be used for drinking in the future.  It has been determined that there is a minimal potential
 for release of metals in leachate from the stockpiled fine slag, and that the stockpiled fine slag
 poses an insignificant impact on water quality (EPA, 1996).

 6.3    RECREATIONAL USER EXPOSURE TO SLAG

 The AV Smelter Slag Pile area is situated in an area presently zoned as industrial/mining and is
 not considered a recreational use area, thus, there is no complete exposure pathway.

 6.4    WORKER EXPOSURE TO SLAG

 There are no current worker exposure pathways to the stockpiled fine slag.  The Selected
 Remedy  provides a contingency for resource utilization, which may be undertaken in the future.
 The EPA has determined that resource utilization of the stockpiled fine slag is only appropriate if
 it is encapsulated for reuse, to deter the potential release of airborne particulates and eliminate
 potential risk associated  with resource utilization activities. Encapsulation can include the use of
 fine, slag  in concrete or asphalt aggregate; or as road base, backfill or other construction material
 as long as the fine slag is chemically bound or physically separated from any exposure scenario
 by a barrier consisting of another material. Dust suppressants to control paniculate emissions
 and best management practices to control stormwater runoff would also be employed to contain
 contaminant releases during implementation of the contingency remedy.

 In response to concerns raised by Leadville officials and business leaders over potential liability
associated with  business development within a Superfund Site, EPA developed action  levels to
determine if chemical concentrations were of concern at any locations presently zoned for
commercial and industrial purposes. Action levels were developed only for arsenic and lead, the
contaminants of most concern at the Site.  The action levels were developed only for soil and
dust ingestion; exposure to other media (e.g., slag piles, waste piles) and exposure to soil/dust via
other pathways  (e.g., dermal) are considered of insignificant concern for workers.

The soil action level for  lead based on commercial/industrial exposure to soil and dust ranged
 from as low as 2,200 parts per million (ppm) to as high as 19,100 ppm with central tendency
 values in the 6,100 to 7,700 ppm range.  Lead concentrations in soils in and around the slag piles
(maximum lead concentration of 794 ppm) were well below the lead action level (EPA 1996).
 Record of Decision
Stockpiled Fine SlaB (OU3)  '
 5I29SP.U280-OI4\FINALROD'.OU3ROD:.WPD

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 Soil action levels for arsenic based on commercial/industrial exposure to soil and dust ranged
 from as low as 330 ppm to as high as 1,300 ppm, with central tendency values in the 610 to 690
 ppm range. Arsenic concentrations in soils in and around the slag piles (maximum arsenic
 concentration of 5.7 ppm) were well below the lowest arsenic action level.

 6.5    ENVIRONMENTAL EXPOSURE TO SLAG

 6.5.1   AQUATIC EXPOSURE

 There are no aquatic exposure pathways to stockpiled fine slag due to the lack of release
 mechanisms.  No evidence of transport of slag fines by surface water runoff was observed at any
 of the examined piles.  Slag does not appear to be transported from piles onto adjacent soils in
 rivulets or channels. Pile integrity, especially for fines piles where this is most critical, appears
 intact.  Surface water runoff is not a potential release mechanism for the AV Smelter Slag Pile.

 Additionally, air pathway analysis results indicate that wind erosion is not a viable release
 mechanism for the lead slag piles, including the AV water-quenched and sorted fines piles.
 Leaching to groundwater is also not a pi•-.  ntial release mechanism. Testing in subslag material
 indicates that leachate  from slag does not contribute to elevated metals concentrations in the
 vadose zone beneath the slag piles.  This conclusion is supported by the lack of acid-generating
 potential and the neutral-to-basic pH of the slag and subslag materials.

 6.5.2   TERRESTRIAL EXPOSURE

 Terrestrial exposure pathways to the stockpiled fine slag are unlikely to be significant.  The slag
 piles do not offer any viable habitat or sustenance for terrestrial receptors. Although terrestrial
 receptors (i.e., birds, mammals) could access the slag piles, there is no habitat or food source to
 attract these receptors.  As stated above, wind erosion, leaching, and surface water runoff are not
 considered potential release mechanisms for the slag piles, which considerably reduces the
 potential for terrestrial  receptors to contact slag in more attractive environs.
Record oT Decision
Slockpiled Fine Slag (OU 3)                           r»C 1 C
5I298JVJ280-OI-I FJNALROD OtmOD'.WPD               Ub- 1 J

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                        7.0 DESCRIPTION OF ALTERNATIVES

 A brief description of the three alternatives evaluated in the Stockpiled Fine Slag FS for the AV
 Smelter Slag Pile (Terranext, 1996a) is provided below.  All alternatives presented in the FS
 were evaluated against the nine criteria described in the next section, and then compared with
 each of the other options.

 Alternative 1; No Action

 This alternative leaves the stockpiled fine slag in place with no remediation, engineering or
 institutional controls, or long-term maintenance. Generally, the No Action Alternative is
 provided for consideration as a baseline against which other technologies can be compared, in
 accordance with the NCP. No Action is protective of human health and the environment, and is
 considered effective because no complete human or ecological exposure pathways were
 identified.  However, a site-wide surface and groundwater monitoring program will be developed
 once all source areas have been addressed. Monitoring will continue until  EPA determines that
 such monitoring is no longer necessary to ensure that human health and the environment are
 protected. D&RGW would conduct any required monitoring at the stockpiled fine slag pile to
 ensure that it poses no threat to human health or the environment. This alternative is technically
 feasible and cost-effective, since it does not rely on any technology and has no cost (EPA, 1996).

 Alternative 2: Institutional Controls

 Institutional controls involve restricting access or activities that could result in human contact
 with the slag or increase the potential for leaching  from stockpiled fine slag. Controls include
 fencing, land-use restrictions, or deed restrictions.  Additionally, community awareness programs
could be implemented to alert the community to any physical hazards associated with the fine
slag.  Controls could be implemented separately or in combination. The option considered is to
fence and maintain the stockpiled fine slag located at the A V Smelter Slag Pile. Fencing would
eliminate the potential direct contact pathway with the fine slag piles, would be protective of
human health and the environment because no complete human or ecological exposure pathways
would exist (that is, children would not have  access to the piles), and potential for release of
metals in leachate from the stockpiled fine slag would remain minimal. Fencing would also be
technically feasible.  Costs associated with fencing are $163,970 with inspection and
maintenance costs of $8,443 for a 30-year period (EPA, 1996).

Alternatives: Resource Utilization

The utilization of stockpiled fine slag as a resource could involve a number of activities and/or
processes. At present, although options have been identified, it is not possible to ascertain if or
when the entire volume of stockpiled fine slag could be reused. Two options for the resource
utilization (materials reuse) were identified in the FS: 1) to process the slag as aggregate for
asphalt or concrete, 2) to use slag materials for stand-alone material in construction, such as
backfill for roadbase material or pipe bedding.
Record of Decision
Stockpiled Fine Slag (OU 3)                           j~c  .,
5I298P:U2SO-OI4\FINALROD'OUJROD:.UT»               L>O- 1 O

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 Resource utilization would be protective of human health and the environment because
 appropriate environmental controls for particulates emissions and stormwater runoff would be
 required to control contaminant releases. Consideration must also be given to any toxic leaching
 potential for the fine slag.  Resource utilization may marginally decrease the minimal metals
 concentrations in the stockpiled fine slag leachate through overall volume reduction.  However,
 the effectiveness and implementability of this alternative would be affected by the regional
 market demand for the material.  Efforts conducted to identify markets have been unsuccessful to
 date, but a potential for future markets exists. Therefore, the EPA has determined that this
 alternative should be included as a contingency with "No Action" as the preferred alternative
 (EPA. 1996). However, resource utilization of the stockpiled fine slag is only appropriate if it is
 encapsulated prior to its use or reuse. Cost effectiveness is hindered by the distance the slag
 material is located from a major market and the cost associated with sorting the slag.  Cost for
 use of the fine slag as aggregate is estimated  as a $1,120,000 loss after resale, while the cost for
 use as fill material is estimated as a $244,625 loss after resale (EPA, 1996).
Record of Decision
Stockpiled Fine Slag (OU 3)                           ,~ „  . _
5i:9SP:U2SO-OI4'.FINALROD'.OU3ROD2.WD                JJo-1 /

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         8.0 SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES

 Section 300.430(e)(9) of the NCP requires that the agencies evaluate and compare the remedial
 cleanup alternatives based on the nine criteria listed below. The first two criteria, (1) overall
 protection of human health and the environment and (2) compliance with applicable or relevant
 and appropriate requirements (ARARs) in Appendix A, are threshold criteria that must be met
 for the Selected Remedy. The Selected Remedy must then represent the best balance of the
 remaining primary balancing and modifying criteria.

 8.1    EVALUATION AND COMPARISON CRITERIA

 8.1.1   THRESHOLD CRITERIA

 1.     Overall protection of human health and the environment addresses whether or not a
       remedy provides adequate protection and describes how potential risks posed through
       each pathway are eliminated, reduced, or controlled through treatment, engineering
       controls, or Institutional Controls.

 2.     Compliance with ARARs addresses whether or not a remedy will comply with identified
       federal and state environmental and siting laws and regulations.

 8.1.2   PRIMARY BALANCING CRITERIA

 3.     Long-term effectiveness and permanence refers to the ability of a remedy to maintain
       reliable protection of human health and the environment over time.

 4.     Reduction of toxicity. mobility and volume through treatment refers to  the degree that the
       remedy reduces toxicity, mobility, and volume of the contamination.

 5.     Short-term effectiveness addresses the period of time needed to complete the remedy and
       any adverse impact on human health and the environment that may be posed during the
       construction and implementation period until cleanup goals are achieved.

 6.     Implementabilitv refers to the technical and administrative feasibilities  of a remedy,
       including the availability of materials and services needed to carry out a particular option.

 7.     Cost  evaluates the estimated capital costs, operation and maintenance costs, and present
       worth costs of each alternative.

8.1.3   MODIFYING CRITERIA

8.     State acceptance indicates whether the State (CDPHE), based on its review of the
       information, concurs with, opposes, or has  no comment on the preferred alternative.
Record of Decision
Scockpiled Fine SljB (OU 3)                          _^c  ' _
5I298P:U280-OM\FINALROD\OU.:IROD2.WI>D               L>O- 1 O

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 9.     Community acceptance is based on whether community concerns are addressed by the
       Selected Remedy and whether or not the community has a preference for a remedy.

 8.2    EVALUATING THE STOCKPILED FINE SLAG ALTERNATIVES

 The following is a brief summary of the agencies' evaluation and comparison of stockpiled fine
 slag alternatives. Additional details evaluating the alternatives are presented in the FS. This
 section evaluates the performance of the stockpiled fine slag alternatives against the nine criteria
 discussed above, and compares it with the other possible options.  Information for this section
 was obtained from the Final Stockpiled Fine Slag FS (Terranext, 1996a).

 8.2.1  OVERALL PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT

 This criterion is based on the level of protection of human health and the environment afforded
 by each alternative. All of the alternatives are protective of human health.  No complete human
 or ecological exposure pathways have been identified. Based upon the chemical composition of
 the slag and soil sampling conducted beneath the slag, the potential for release of metals in
 leachate from the stockpiled fine slag is minimal.  The stockpiled fine slag has, at most,
 insignificant non-point source impact on water quality.

 The physical features of the slag piles have remained relatively unchanged for many decades.
 That fact, combined with the determination that the only potential release pathway is through
 leachate, suggests that the status of the slag is not  likely to change in the near or long term.
 Therefore all three alternatives are protective of human health and the environment.

 8.2.2  COMPLIANCE WITH APPLICABLE OR RELEVANT AND APPROPRIATE
       REQUIREMENTS (ARARs)

 This criterion is based on compliance with chemical-, location-, and action-specific ARARs.
 ARARs are presented in Appendix A. All of the alternatives meet ARARs.  Groundwater quality
 is a function of the active interchange with surface water degraded by the release of more mobile
 metal species from the multitude of other contaminant sources in the vicinity. The potential for
 non-point source metals loading to surface water from stockpiled fine slag leachate is minimal to
 nonexistent. The use of institutional controls on the stockpiled fine slag will not have any effect
 on groundwater quality. Non-point source, Best Management Practices (BMP) to-be-considered
 criteria have been implemented along the slag piles contacting California Gulch.

 8.2.3  LONG-TERM EFFECTIVENESS AND PERMANENCE

 This criterion is based on the magnitude of residual risk and adequacy and reliability of controls.
No Action is an effective long-term alternative.  The only identified release pathway determined
 to have any potential to contribute to human or environmental risks is the potential for metals to
 leach from the stockpiled fine slag.  Based upon subslag sampling, metals have not leached and
will not leach from the stockpiled fine slag in concentrations that will have an adverse impact on
soils, surface water or groundwater  in the vicinity.  Based upon the hardness of the slag, the lack
Record of Decision
Siockpiled Fine Slaj: (OU 3)                          _ c . Q
5i:98P.O:gO-OI4-.FINALROD'.OU3ROD:.WPD               Do- I 7

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 of acid-generating potential and the absence of significant metals in soils beneath the slag, the
 potential for exposure to metals of concern found in the slag is unlikely to change in the long
 term.  Institutional controls can be effective in the long term, but are not permanent. Fencing
 requires inspections, maintenance and community awareness, and must be renewed or replaced
 periodically. Resource utilization represents a reliable alternative which uses known
 technologies, limited only by the regional market demand for the stockpiled fine slag. Resource
 utilization will not have a dramatic effect on the residual risk, as the pre-resource utilization risks
 are minimal.

 8.2.4   REDUCTION OF TOXICITY, MOBILITY, OR VOLUME THROUGH
        TREATMENT

 This criterion is based on the treatment process used; the amount of contamination destroyed or
 treated; the reduction of tdxicity, mobility, and volume; the irreversible nature of the treatment;
 the type and quantity of residuals remaining; and the statutory preference for treatment.

 Institution controls and No Action do not further reduce the very limited toxicity or mobility of
 metals of concern in the stockpiled fine slag. In the absence of complete exposure pathways,
 there is no indication that toxicity and mobility of hazardous substances in the slag pose a human
 health risk. From a land-use perspective, the slag volume is not an issue as tourists  come
 specifically to observe historic mining practices.  Implementation of institutional controls or the
 No Action alternative, however, will not reduce the volume of the fine slag found at the  site.

 Over time, reuse could reduce the very limited potential toxicity and potential mobility of the
 stockpiled  fine  slag.  From a land-use perspective, the change in the total volume of all types of
 slag will not be significant if only the stockpiled fine slag is utilized.

 8.2.5   SHORT-TERM EFFECTIVENESS

 This criterion is based on the degree of community and worker protection offered, the potential
 environmental impacts of the remediation, and  the time until the remedial action is completed.
 No action and institutional controls do not create additional risk to the Leadville community
 during implementation. For institutional controls, workers and the community can be adequately
 and reliability protected if fencing were to be installed.

 Resource utilization can also be implemented with no additional risk to the Leadville
 community. Workers and the community can be adequately and reliably protected from fugitive
 particulates and changes in storm-water drainage when the stockpiled fine slag is utilized.

 8.2.6   IMPLEMENTABILITY

This criterion is based on the ability to perform construction and implement administrative
actions. No Action is technically feasible as it does not rely on any technology. As the status
quo, no action is implementable.
Record of Decision
Stockpiled Fine SIM (OU 3)                           _
5I298P:U280-ONHSALROD\OU3ROD2 WPD               JJb-21)

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 Institutional controls are technically feasible, as reliable fencing can be procured and installed
 readily by local contractors.  Land-use restrictions would require action by either the Lake
 County Commissioners or the Leadville Town Council. Therefore, because further action is
 needed by a third party, the potential of implementability of land-use restrictions cannot be
 predicted.

 Resource utilization is also technically feasible but there are unknowns as to the marketability of
 the resource. Demand for the stockpiled fine slag will be dependant on a number of factors,
 including but not limited to, the level of construction activity in the vicinity of Leadville.

 8.2.7  COST

 Alternative 1: No Action

 As there are no costs associated with No Action, it is the most cost effective alternative.

 Alternative 2: Institutional Controls

 Institutional controls involve fencing and maintenance of the stockpiled fine slag located at the
 AV Smelter Slag Pile. Fencing the AV pile would have present value capital and labor costs of
 $161,000 and inspection and maintenance costs of $8,500 to inspect and maintain over a 30-year
 period indicated in the summary in Table 1.

 Alternative 3: Resource Utilization

 Resource utilization does not presently appear to be a cost-effective option even if market
 demands for the material are identified. Efforts conducted to identify markets have been
 unsuccessful to date.  The options considered are 1) to process slag for use as a concrete or
 asphalt aggregate in construction, and 2) to utilize slag materials for a stand-alone material in
 construction, such as a backfill or pipe bedding.

 The cost effectiveness of these  options is hindered by the distance the slag material is located
 from a major market and the cost associated with sorting the slag. Cost estimates and a cost
 summary are included in Table 1.  Estimates have been provided for use of the fine slag for
 aggregate ($1,120,000 loss after resale) and for use in fill material ($244,625 loss after resale).

 8.2.8   STATE ACCEPTANCE

 The State has been consulted throughout this process and concurs with the Selected Remedy.

 8.2.9   COMMUNITY ACCEPTANCE

 Public comment on the RJ/FS and Proposed Plan was solicited during a formal public comment
period extending from September 27 to October 28, 1996. It is assumed that the community is
generally supportive of EPA's No Action alternative since no comments were generated during
 Record of Decision
Stockpiled Fine Slat' (OU 3)                           _ c _
5i:9SP:'J280-OM-HNALRODOU3ROD2.WPD               Dd-2 I

-------
 the formal public comment period. In addition, only two oral comments were raised during the
 public meeting held October 3, 1996.  These comments were in regard to the volume of the fine
 slag pile and the nature of the soil beneath the Harrison St. slag pile, which is not relevant to this
 ROD.

 8.2.10 SUMMARY

 The FS used a comparative analysis to qualitatively evaluate the performance of each alternative
 in relation to each specific evaluation criterion.  The purpose of this comparative analysis is to
 identify the advantages and disadvantages of each alternative relative to one another so that key
 tradeoffs could be identified.

 A grid comparison method was used to rank the alternatives and their attainment relative to the
 NCP criteria set forth in the SFS.  Alternatives were ranked on a scale of 1 to 5, with 5 being the
 highest attainment of the criterion. Total scores for each alternative were:  Alternative 1: No
 Action at 41; Alternative 2: Institutional Controls at 39; and Alternative 3: Resource Utilization
 at 36. Table 2 provides a grid comparison method to rank the alternatives and their attainment
 relative to the following criteria.

 •      Protection of Human Health and the Environment - All three alternatives are protective of
       human health and the environment.
 •      Attainment of ARARs - All three alternatives attain ARARs.
 •      Long-Term Effectiveness - All three alternatives have similar long-term effectiveness.
       Reuse of the stockpiled fine slag would marginally reduce the residual risk because of
       volume reduction. None of the alternatives are subject to technology failure from age or
       wear and tear.
 •      Reduction of Toxicity, Mobility or Volume - None of the three alternatives reduce the
       toxicity and mobility of metals of concern found in the fine slag.
 •      Short-Term Effectiveness - All three alternatives can be implemented in a manner which
       protects the Leadville community and the workers implementing the remedy. The No
       Action alternative eliminates disturbances of the fine grain slag and requires no workers.
       Implementability - All three alternatives  are implementable. Deed restrictions are in
       effect. Land use restrictions may not be implementable from and administrative
       perspective as they require approval by the Lake County Commissioners. Reuse requires
       that there be a commercial market or internal need for the stockpiled fine slag which, at
       this time, is uncertain.
       Cost - No Action is the most cost-effective approach to meeting the remedial action
       objectives and attaining ARARs. There are essentially no costs associated with this
       remedial option.
•      State Acceptance - CDPHE has been consulted throughout the RI/FS process.
•      Community Acceptance - The community has been consulted throughout the RI/FS
       process.

Selection of the No Action alternative was based on this analysis.
Record of Decision
Stockpiled fine Slat: (OU 3)
5I293I'.\3280-OU'.FINALRODOU3ROD2.WI'D

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                                9.0   SELECTED REMEDY

 Based upon consideration of CERCLA requirements, the detailed analysis of alternatives, and
 public comments, EPA has determined that the No Action alternative presented in the Proposed
 Plan, with no modifications, is the appropriate remedy for the stockpiled fine slag at the AV
 Smelter Slag Pile of OU3 within the California Gulch Superfund Site. The No Action alternative
 leaves the stockpiled fine slag in its existing condition with no control or cleanup planned.  The
 No Action alternative, as described in the Proposed Plan, includes a contingency for future
 utilization of the slag, if it is encapsulated prior to its use or reuse.

 The No Action alternative is protective of human health and the environment, and is considered
 effective because no complete human or ecological exposure pathways were identified and
 because the potential for release of metals in leachate is minimal. Based on subslag sampling.
 metals have not leached and will not leach from the stockpiled fine slag in concentrations that
 will have an adverse impact on soils, surface water, or groundwater in the area. Slag hardness,
 the lack of acid-generating potential, and the absence of any significant metals beneath the slag
 also indicate that the potential for exposure to metals of concern found in the slag is unlikely to
 change in the long term. This alternative is technically feasible and cost effective, since it does
 not rely on any technology and has no cost.

 Resource utilization would only implemented if future regional market demand exists for the
 material. Encapsulation of the fine slag ensures that the contingency remedy is also protective of
 human health and the environment. Encapsulation can include the use of the fine slag in
 concrete or asphalt aggregate; or as road base, backfill or other construction material as long as
 the fine slag is chemically bound or physically separated from any exposure scenario by a barrier
 consisting of another material. Dust suppressants to control paniculate emissions and best
 management practices to control stormwater runoff would also be employed to contain
 contaminant releases during implementation of the contingency remedy.
Record of Decision
Stockpiled Fine SbB (OK 3)
5l293P:'.32gO-0|4-.FINALRODOU3ROD:.WPD

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                        10.0   STATUTORY DETERMINATIONS

 Under CERCLA Section 121, EPA must select a remedy that is protective of human health and
 the environment; that complies with ARARs; is cost effective; and utilizes permanent solutions,
 and alternative treatment technologies, or resource recovery technologies to the maximum extent
 practicable. In addition, CERCLA includes a preference for remedies that include treatment
 which permanently and significantly reduces the volume, toxicity, or mobility of hazardous
 wastes as a principal element. However, the Selected Remedy, No Action, does not satisfy the
 statutory preference for treatment as a principal element of the remedy. Treatment was
 considered unnecessary as the Selected Remedy is protective of human health and the
 environment.  The following sections discuss how the Selected Remedy meets statutory
 requirements.

 10.1   PROTECTION OF HUMAN HEALTH AND THE ENVIRONMENT

 The selected remedy is protective of human health and the environment because 1) no complete
 human or ecological  exposure pathways were identified and 2) metals have not leached and will
 not leach from the  stockpiled fine slag that will have an adverse impact on soils, surface water or
 groundwater in the area.

 Because the estimated action levels for recreational land-use scenarios are significantly above
 current surficial soil concentrations for both lead and arsenic, there appears to be relatively little
 uncertainty in  the conclusion that current surface soils do not pose unacceptable risk levels to
 recreational site visitors anywhere within the OU boundaries (EPA, 1995b).  In addition, the AV
 Smelter Slag Pile area is situated in an area presently zoned as industrial/mining and is not
 considered a recreational use area (EPA, 1996).

 There are no current worker exposure pathways to the stockpiled fine slag. The Selected
 Remedy provides a contingency for resource utilization, which may be undertaken in the future.
 The EPA has determined that resource utilization of the stockpiled fine slag is only appropriate if
 it is encapsulated prior to its use or reuse, to deter the potential release of airborne particulates
 and eliminate potential risk associated with resource utilization activities. Dust suppressants to
 control paniculate  emissions and best management practices to control stormwater runoff would
 also be employed to contain contaminant releases during implementation of the contingency
 remedy.

 The soil action level for lead based on commercial/industrial exposure to soil and dust ranged
 from as low as 2,200 parts per million (ppm) to as high as 19,100 ppm with central tendency
 values in the 6,100 to 7,700 ppm range.  Lead concentrations in soils in and around the slag piles
 (maximum lead concentration of 794 ppm) were well below the lead action level (EPA 1996).

 Soil action levels for arsenic based on commercial/industrial exposure to soil and dust ranged
 from as low as 330 ppm to as high as 1,300 ppm, with central tendency values in the 610 to 690
ppm range. Arsenic concentrations in soils in and around the slag piles (maximum arsenic
 concentration of 5.7 mg/kg) were well below the lowest arsenic action level.
 Record of Decision
Stockpiled Fine Stif (OU .1)
 5I298P:U280^)M'.FINALROD1OU3ROD2.WPD

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 10.2   COMPLIANCE WITH ARARs

 The Selected Remedy will comply with all ARARs identified in Appendix A to this ROD.  No
 waiver of ARARs is expected to be necessary.

 10.3   COST EFFECTIVENESS

 Section 300.430(f)(ii)(D) of the NCP requires evaluation of cost effectiveness. The Selected
 Remedy is cost effective because it has no cost.

 10.4   UTILIZATION OF PERMANENT SOLUTIONS AND ALTERNATIVE
       TREATMENT TECHNOLOGIES (OR RESOURCE RECOVERY
       TECHNOLOGIES) TO THE MAXIMUM EXTENT POSSIBLE

 No remedial action is necessary to ensure protection of human health and the environment.  The
 contingency allows for resource recover,' if supported by regional market demand.

 10.5   PREFERENCE FOR TREATMENT AS A PRINCIPAL ELEMENT

 Treatment of the stockpiled fine slag at the AV Smelter Slag  Pile was not considered because the
 No Action alternative is protective of human health and the environment.
Record of Decision
Slockpilcd Fine Shf (OU 3)
5I29SP.O:80-OI4-.FINALROD-OU3ROD: WPD

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                 11.0   DOCUMENTATION OF SIGNIFICANT CHANGES

 The Proposed Plan for stockpiled fine slag at the AV Smelter Slag Pile was released for public
 comment in September 1996. The Proposed Plan identified Alternative 1, No Action, as the
 preferred alternative, with the contingency that resource utilization may be undertaken in the
 future. Resource utilization of the stockpiled fine slag would only be appropriate if it is
 encapsulated prior to its use or reuse.  No comments were received during the public comment
 period. Subsequently, EPA determined that no significant changes to the remedy, as it was
 originally identified in the Proposed Plan, were necessary.
Record of Decision
Stockpiled Fine Slay (OU 3)
5l29gP.U:SO-OI4TJNAI.ROD'.OU3ROD2 WPD

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                                  12.0 REFERENCES
 Morrison Knudsen Corporation (MK).  1992. Report for Lead Slag Pile Remedial Investigation
 at the California Gulch Site Leadville, Colorado, prepared for Denver & Rio Grande Western
 Railroad. December 11.

 Terranext. 1996a.  Final Stockpiled Fine Slag Feasibility Study, prepared for Denver & Rio
 Grande Western Railroad.  May 13.

 Terranext. 1996b.  Work Plan Consolidation of Fine Slag.  Prepared for Denver & Rio Grande
 Western Railroad.  November. 12.

 U.S. Department of Commerce. 1990. Selected Population and Housing Characteristics.
 Bureau of the Census.

 U.S. Environmental Protection Agency (EPA).  1997.  Ecological Risk Assessment for the
 Terrestrial Ecosystem. California Gulch NPL Superfund Site, Leadville, Colorado. Prepared by
 Roy F. Weston, Inc., January, 1997.

 U.S. Environmental Protection Agency (EPA).  1996.  Proposed No Action Plan for Stockpiled
 Fine Slag, Arkansas Valley Smelter Slag Pile, California Gulch Superfund Site, Leadville,
 Colorado. September.

 U.S. Environmental Protection Agency (EPA).  1995a.  Draft Final Findings of Metal Speciation
 Investigations at the California Gulch NPL Site, Prepared by John W. Drexler and Roy F.
 Weston, Inc., October 1995.

 U.S. Environmental Protection Agency (EPA).  1995b.  Baseline Human Health Risk
 Assessment for the California Gulch Superfund  Site - Part A - Risks to  Residents from lead
 prepared by Roy F. Weston, Inc., Draft final November 6, 1995.

 U.S. Environmental Protection Agency (EPA).  I995c.  Baseline Human Health Risk
 Assessment for the California Gulch Superfund  Site - Part C - Evaluation of Recreational and
 Worker Scenarios prepared by Roy F. Weston, Inc., April 17, 1995.

 U.S. Environmental Protection Agency (EPA).  1995d.  Final Baseline Aquatic Ecological Risk
 Assessment. California Gulch NPL Site. Prepared by Roy F. Weston, Inc., September, 1995.

 U.S. Environmental Protection Agency (EPA).  1991. Preliminary Human Health Baseline Risk
 Assessment for the California Gulch NPL Site, Leadville, Colorado.  Prepared by Roy F.
 Weston, Inc. for the U.S. EPA, December 1991.
Record of Decision
Stockpiled Fine Slalom)

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 U.S. Environmental Protection Agency (EPA).  1989.  Draft Phase II Remedial Investigation
 Technical Memorandum, 1986-1987, California Gulch Site. Leadville.  Colorado. U.S. EPA,
 Prepared by CH2M Hill, May 1989.

 Woodward Clyde Consultants (WCC). 1993. Draft Terrestrial Ecosystem Evaluation Report,
 California Gulch Site, Leadville, Colorado. April.
Record of Decision
Stockpiled Fine Slag (OU 3)
5l298P:V3280-OI4-.JrINALRODOU3RO[?2.WPD

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FIGURES

-------
                                                                              CALIFORNIA GULCH
                                                                              SUPERFUND SITE
CUV FEDERAL PROGRAMS CORPORATION
     ! C«*v fr«M«r k UcX«« kw.
      GENERAL LOCATION  MAP
CALIFORNIA GULCH  SUPERFUND  SITE
       LEADVILLE, COLORADO
                                                                                                figure 1

-------
ARKANSAS VALLEY
                                                                                          OpeiiiWe Units tint)
                                                                                         Aicas o
                                     CALIFORNIA GULCH SUPERFUNO SITE
                                           AND OPEFtABLE  UNITS
                                           LEADVILLE, COLORADO

-------
N 510.500
                                                                                                                                   \ Cj ownma (A« CZOUD) >i iff


                                                                                                                                      SOHIO rim (AU-CDOUI) aft
                                                                                                                                      mm umoom iii-ccaa/*»n

                                                                                                                                      •MUSI-SI aa

                                                                                                                                          OT AIM-ODOO KM

                                                                                                                                      <«u or WOK buaunix icnog

                                                                                                                                   «-s stcnoN imnriuna
                                                                                                                                           LECENQ
                                                                                                                                      J" $uw«cf eatiau* IHIIXVA
                                                                                                                                      »oo 1000* 10 ctcvArioN UMIOUKS
                                                                                                                                      •ua oumon (>n-ooaat
                                                                           GENERAL LOCATION MAP
                                                                           CURRENT SURFACE AREAS
                                                                      VOLUMES AND ANGLES  OF REPOSE
                                                                         ARKANSAS VALLEY SLAG  PIL£
                                                                             LEADVILLE. COLORADO

-------
                                                                            V
                                                          .««  ffiswar  ,.  •••<•
                                                               SSSSR,.;.:.---^
                                                                                             LECEWQ


                                                                                          r BJWMZ ctxcoo" rnitnvji
                                                                                          ciivAtiOMi AMC VALUC nut 1.0001

                                                                                          *KMOOU
"*niiai*ii-aao)>ii/r
''"OaHrB AU-GDOUB
«o>-ie nia i.u.coao, 0/r
"•"««ua>«1io.ojUO«,,|1€J
'           N
                                     GENERAL LOCATIONS
                              AND  RECONNAISSANCE INFORMATION
                                 ARKANSAS  VALLEY SLAG  PILE
                                     LEADVILLE. COLORADO
                                                                                                            figure 4

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TABLES

-------
                                                                  TABLE I

                                             ESTIMATES OF COSTS FOR REMEDIAL ALTERNATIr-ES

                                                                 OPTION I
                                 INSTITUTIONAL CONTROLS (I)

                                 FESCE THE A V FINE SLAG PILE
CALIFORNIA GULCH
ARKANSAS VALLEY SLAG PILE
LEADWLLE

ALTERNATIVE:

ITEM:

DIRECT CAPITAL COSTS.

(Includes Labor. Equipment and Materials. Unless Otherwise Noted)



                              COSTS
                          COMPONENT

  /.         Mobilize Materials

  .'.         Office/Storage trailer (8'x30')

  3.         Earthwork (-150 hp bulldozer)

  4.         Utilities
            Electric
            Phone
            Sanitary Station

  5.         Fence Materials
            Fencing
            Comer Post
            Braces
            Double Swing Gales
            Locks

  TOTAL DIRECT COSTS

  INDIRECT CAPITAL COSTS (% ojDirect Capital Costs)

  I.         Engineering and Design (10% of Capital Costs)
  2.         Contingency Atlo wance (20% of Capital Cost)
  3.         Other Indirects
            Regulatory License/Permits (}% of Direct Capital Costs)

  TOTAL INDIRECT COSTS

  PRESENT VALUE OF OPERATION AN!) MAINTENANCE COSTS
  Annual Inspection atuj maintenance

  TOTAL COS1S

  ASSUMPTIONS/COMMENTS:


UNfT
Lump
Lump
Cubic Yards
Month
Month
Month
Lineal Feet
Each
Each
Opening
Each


QVASTITf
1
I
5.000
1
1
1
5.300
50
106
3
3

u\/r
COSTS
S:. '00.00
SI.SOOOO
$: so
SI. 300.00
S6.0II.OU
590.011
$16.00
S9500
335.00
svo.on
SIS 00
TOTAL
CAPITAL
COSTS
$2. -00
SI.800
S12.SOO
SI. 300
S600
590
584.800
5-t. 750
S3.- 10
52.910
SJS
                                                                   Ytar
                                                                                          30
                                                                                                          3-50 on
5115.205



 sn.i:i
 323.0-11

  55.760

 S-I6.0S1

  SH.-t-iS


SI 63.970
  I.          Eight (8) loads of fencing materials will be hauled using flatbed trailers.
  2.          Includes mob and demob, set-tip and leveling. teor~down and monthly leasing charge.
  3.          Earthwork consists of consolidating sorted and wale r-quenchedfine slags before fencing: no nnth or demoh, onsne contractor utilized.
  •f.          Fencing is 6 go. Galvanized wire. 6' high, no barbed wire.
  5.          Gales are 20' wide and include posts oitd hardware.


Source: Teirane«i. 1996a
P:V3280-OI4WP\ROD\TABLEI.WPD

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 CALIFORNIA GULCH
 LEADVILLE. COLORADO

 ALTERNATIVE:

 ITEM:
                                                             TABLE I (Continued)

                                             ESTIMATES OF COSTS FOR REAtEDIAL ALTERNATH'ES
                               RESOURCE UTILIZATION (I)

                               FINE SLAG ADDITIVE MATERIAL IN CONSTRUCTION
                               Aggregate for concrete or asphalt, additive to building materials, additive to
                               grout, concrete end slurry formations)
DIRECT CAPITAL COSTS
(Includes Labor. Equipment and Materials, Unless Otherwise Holed)
                           COMPONENT
  I.   Rescreen material
                                                                 UNIT

                                                                 Cubic Yards

                                                                 Cubic Yards
                                                                   Cubic Yard
                                                                   Cvbic Yard
QUANTITY

 190.000

 190.000
2.  Load and haul

TOTAL DIRECT COSTS

INDIRECT CAPITAL COSTS (% of Direct Capital Costs)

I.  Engineering aiuJ Design (10% of Capitol Costs)
2.  Contingency Allo wance (20% of Capital Cost)
3.  Other Indirect!
    Regulatory License/Permits (5% of Direct Capital Costs)

TOTAJ. INDIRECT COSTS

CREDITS FROM SALE OF PRODUCT A U TER1AL

I.  Additive
2.  Backfill Material

TOTAI. CREDIT

TOTAL COSTS/PROriT(S)

ASSUMTTIONStCOMMENTS-
  I.  A Vfine stag pile volumes are used to compute costs.
  }.  90% of material wilt be suitable for use as additive.
  3.  10% of material used as backfill material.
  •/.  No operations and maintenance costs are necessary over an extended period
  J.  Credits from sale of product material ha\'e been reduced to reflect tranxportalum casts to a major market.
Source: Terranext, 1996a
COSTS

  S5.68

  S3.2S
n.ooo
 19.000
  S6.SO
  S3.10
    TOTAL
    COS1S

 Sl.0-9.200

   S61-.SOU

 SI. 696.700



   5169.670
                                                                                                                            S8J.833

                                                                                                                           S593.84!
5(1.111.500)
   5(i8.900)

S(I.I70.JOO)

 SI.I20.I-IS
P:\3280-0 M\WFJIOD\TABLE I .WPD

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 CALIFORNIA GULCH
 LEADWLLE. COLORADO

 ALTERNATIVE:

 ITEM:
                                                            TABLE I (Continued)

                                            ESTIMATES OF COSTS FOR RE\(EDIAL ALTERNATIVES
                              RESOURCE UTILIZATION O

                              USED AS STAND ALONE MATERIAL IN CONSTRUCTION
                              (Fill material)
                                                                  UNIT             QUANTITY

                                                                  Cubic Yards         IVO.OOO
 DIRECT CAPITAL COSTS:
 (Includes Labor. Equipment and Materials. Unless Otherwise Noted)
                         COMPONENT

I.  Load and Haul

TOTAL D1RECTCOSTS

INDIRECT CAPITAL COSTS (% of Direct Capuol Costs)

I.  Engineering and Design (10% oj Capital Costs)
2.  Contingency Allowance (20% oj Capital Cost)
3.  Other Indirect*
    Regulatory License/Permits (}% of Direct Capital Casts)

TOTAL INDIRECT COSTS

TOTAL COSTS (Dirtci plus Indirect)

CREDITS FROM SALE OF PRODUCTMATF.RJAl.

I.  Backfill Material

TOTA1. CREDIT
TOTAL COSTS/PROFITS)

ASSUlfl'TIOSirOMMENlS:
  I  AI' Fine slop volumes are used to compute costs.
  ?.  100% of material will he suitable fur use ar backfill.
  3.  l.oad and haul isjor conveyattce losuttahle rail loading Jock.
  •f  Credits from sale of product material have been reduced due to transportation costs to a major mark*!.
  1.  Annual Operations and Maintenance costs are included in estimate.


Source: Terranext, I996a
                                                                                                        CAPITAL
                                                                                                         COSTS
                                                                 . Cubic t'ard
                                                                                     190.000
                                                                                                           33.10
                                                                                                                          TOTAL
                                                                                                                          COSTS
 3617.100



  36 1. ' '10
 S12J.100

  S30.8-S

 31 1 6.i:i

 383J.6H



3(189.000)

3(189.000)
 32 '-1-1.61 5
P:U280-OH\WPlROD\TABLEI.WPD

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                                  TABLE 2
          GRID COMPARISON METHOD FOR ALTERNATIVES ANALYSIS
Criterion
1 ) Protection of Human Health and
Environment
2) Attainment of ARARs
3) Long term Effectiveness
4) Reduction of Toxicity, Mobility or
Volume
5) Short term Effectiveness
6) Implementability
7) Cost
8) State Acceptance
9) Community Acceptance
Total
Alternative 1
No
Action
5
5
4
2 .
5
5
5
5
5
41
Alternative 2
Institutional
Controls
5
5
4
2
4
5
4
5
5
39
Alternative 3
Resource
Utilization
5
5
5
2
3
3
3
5
5
36
Notes: Scale of 1-5, where 5 = Highest Attainment
Source: Terranext, 1996a
P:\J280-OI4\WP\ROD\TABLE2.WPD

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APPENDIX A




  ARARs

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                                  SUMMARY OF FEDERAL AND STATE ARARS
Standard, Requirement,
Criteria, or Limitation
Ciiatlon
Applicable
Relevant and;
....; Appropriate
Description
FEDERAL
Clean Air Act,
National Primary and Secondary
Ambient Air Quality Standards










National Historic Preservation
Act (NHPA)


Executive Order 11593
Protection and Enhancement of
the Cultural Environment



Hazardous Materials
Transportation Act

40 CFR Part 50












!6USC§470etseg.
40 CFR §6.30l(b)
36 CFR Part 63, Part 65,
Part 800
16 USC §470





49 USC § 1801-1813
49 CFR 107, 171-177

No












Yes



Yes





Yes
(for contingency
reuse only)
No












—



—








National ambient air quality standards (NAAQS) are
implemented through the New Source Review Program and
State Implementation Plans (SIPs). The federal New
Source Review program address only major sources. There
will be no emissions associated with the chosen remedial
action in OU3. Emissions associated with the contingency
remedy will be limited to fugitive dust associated with
moving and sorting the slag for reuse. These activities will
not constitute a major source. Therefore, attainment and
maintenance of NAAQS pursuant to the New Source
Review Program are not ARARs. See Colorado Air
Pollution Prevention and Control Act concerning
applicability of requirements implemented through the SIP.
Expands historic preservation programs; requires
preservation of resources included in or eligible for listing
on the National Register for Historic Places.

Directs federal agencies to institute procedures to ensure
programs contribute to the preservation and enhancement
of non-federally owned historic resources. Consultation
with the Advisory Council on Historic Preservation is
required if removal activities should threaten cultural
resources.
Regulates transportation of hazardous materials.


P \J280-OI4\FINALROD\OU3ARAR.FNL

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                                            SUMMARY OF FEDERAL AND STATE ARARS (Continued)
   Standard, Requirement,
    Criteria, or Limitation
        Citation
    Applicable
Relevant and
Appropriate
Description..
                                                                 STATE OF COLORADO
Colorado Air Pollution
Prevention and Control Act
5CCR 1001 .Regulation I,
      Section III.D
       Yes
                  Requires all sources of paniculate emissions to apply
                  technically feasible and economically reasonable control
                  measures. APCD has the authority to ask for a fugitive
                  emission control plan from any location, if blowing
                  paniculate matter is a problem. The site does not need to
                  be in active use for this requirement  to apply. Technically
                  feasible and economically reasonable control measures will
                  be applied to reuse of the stockpiled  fine slag.
Colorado Air Pollution
Prevention and Control Act
     5CCR 1001-3;
  Sections III.D.i.b.c.d.
 Sections III.D.2.b,c,e,f,g.
      Regulation I
Yes (for contingency
    reuse only)
                  Regulation No.  I provisions concerning fugitive emissions
                  for storage and stockpiling activities, haul roads, and haul
                  trucks are applicable (5 CCR  1001-3; Sections
                  llr.D.2.b,c,e,f,g.) to the reuse  contingency.
Colorado Air Pollution
Prevention and Control Act
     5 CCR 1001-4;
       Regulation 2
Yes (for contingency
    reuse only)
                  Provisions concerning odors would be applicable if
                  contingency reuse were to cause objectionable odors.
Colorado Air Pollution
Prevention and Control Act
      5 CCR 1001-5
       Regulation 3
         APENs
Yes (for contingency
    reuse only)
                  Substantive provisions of APENs will be met.
Colorado Air Pollution
Prevention and Control Act
     5 CCR 1001-10
     PartC(l)&(ll)
       Regulation 8
        Yes
  (for contingency
    reuse only)
                  Regulation 8 sets emission limits for lead. Applicants are
                  required to evaluate whether the proposed activities would
                  result in the Regulation 8 lead standard being exceeded.
                  There are no emissions associated with the chosen remedial
                  action.  The contingency reuse in OU3 is not projected to
                  exceed the emission levels for lead, although some lead
                  emissions may occur.  Compliance with Regulation 8 will
                  be achieved by adhering to a fugitive emissions control
                  plan prepared in accordance with Regulation No. I.
       P:V3280-OM\RNALROD\OU3ARAR.FNt

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                              SUMMARY OF FEDERAL AND STATE ARARS (Continued)
Standard, Requirement,
Criteria, or Limitation
Colorado Air Pollution
Prevention and Control
Colorado Water Quality Control
Act, Storm Water Discharge
Regulations
Colorado Noise Abatement Act
Citation
5 CCR 1001-14;
Ambient Air Quality
Standards
5 CCR 1002-2
CRS§§ 25-12-101 to 108
Applicable
Yes (for contingency
reuse only)
Yes
Yes (for contingency
reuse only)
Relevant and
Appropriate


—
Description
Provisions concerning State TSP standards and Federal
PM- 10 standards would apply if contingency reuse occurs,
or if the Site is the subject of fugitive emission complaints.
In such a case, compliance with the applicable provisions of
the Colorado air quality requirements will be achieved by
adhering to a fugitive emissions control plan prepared in
accordance with Regulation No. 1 .
Establishes requirements for storm water discharges (except
portions relating to Site-wide Surface and Groundwater).
Substantive requirements for storm water discharges
associated with construction activities are applicable.
Establishes maximum permissible noise levels for
particular time periods and land use.
P:\3280-OI4\FINALROD\QU3ARAR.FNL

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