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1182109-RBSDMS 

EPA/ROD/R08-99/055 

1999 

EPA Superfund 

Record ofDecision: 

CALIFORNIA GULCH 

EPAID: COD980717938 

OU09 

LEADVILLE, CO 

09/02/1999 
STATE OF COLORADO 

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in the selected mnedial attemttive fbr Operable Unit 9 ofthe Cilifemia Guldi Sayetfiad site. 

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Ken Chkuber, Stne Senator 

Carl MSUer. State Hameaeatatiw 
RECORD OF DECISION 

RESIDENTIAL POPULATED AREAS 

OPERABLE UNIT 9 

CALIFORNIA GULCH SUPERFUND SITE 

LEADVILLE, COLORADO 

September 1999 

U.S. ENVIRONMENTAL PROTECTION AGENCY 

999 18TM STREET SUITE 500 

DENVER, COLORADO 80202 
RECORD OF DECISION 

RESIDENTIAL POPULATED AREAS OPERABLE UNIT 9 

CALIFORNIA GULCH SUPERFUND SITE 

LEADVILLE, COLORADO 

The U.S. Environmental Protection Agency (EPA), with the concurrence ofthe Colorado 

Department of Public Health and Environment (CDPHE), presents this Record ofDecision 

(ROD) for the Residential Populated Areas Operable Unit 9 (OU9) ofthe California Gulch 

Superfund Site in Leadville, Colorado. Residential/populated area soils include those in 

residential yards, vacant lots, parks, school yards, playgrounds, and community use areas, 

including unpaved streets and alleys. The ROD is based on the Administrative Record for 

OU9, including the Residential Soils Feasibility Study, the Proposed Plan, the public 

comments received, including those from the potentially responsible parties (PRPs), and 

EPA responses. The ROD presents a brief summary of site characteristics, 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 etseq., as amended by the 

Superfund Amendments and Reauthorization Act (collectively, CERCLA), 

and, to the extent practicable, the National Contingency Plan (NCP); 

2. Outline the engineering components and remediation requirements ofthe 

Selected Remedy; and 

3. Provide the public with a consolidated source of information about the 

history, characteristics, and risk posed by the conditions of OU9, as well as a 

summary of the remedial alternatives considered, their evaluation, the 

rationale behind the Selected Remedy, and the agencies' consideration of, 

and responses to, the comments received. 

The ROD is organized into 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 

Regional Administrator and the CDPHE Director. 

2. The Decision Summary section provides an overview ofthe OU9 

characteristics, the alternatives evaluated, and the analysis of those 

alternatives. The Decision Summary also identifies the Selected Remedy and 

explains how the remedy fulfills statutory and regulatory requirements; and 
The Responsiveness Summary section addresses public comments received on 

the Proposed Plan, the Residential Soils Feasibility Study, and other 

information in the Administrative Record. 
DECLARATION 

SITE NAME AND LOCATION 

Residential Populated Areas Operable Unit 9 

California Gulch Superfund Site 

Leadville, Colorado 

STATEMENT OF BASIS AND PURPOSE 

This decision document presents the Selected Remedy for OU9 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. 

This decision is based on the Administrative Record for OU9 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 Record Center, located at 999 18* Street, 5* Floor, North Terrace in Denver, 

Colorado. 

The State of Colorado concurs with the Selected Remedy, as indicated by their concurrence 

letter dated September 2,1999. 

ASSESSMENT OF THE SITE 

Soils at the Site have elevated levels of heavy metals as a result of mining and smelting 

operations in the Leadville area. Although metals other than lead are not present at 

concentrations that present risk, levels of lead, if not addressed by implementing the 

response action selected in this ROD, may present an imminent and substantial 

endangerment to public health, welfare, or the environment. 

DESCRIPTION OF THE SELECTED REMEDY 

The California Gulch Superfund Site is divided into twelve media and 

geographically-based operable units (OUs) within the Site. Operable Unit 9, designated as 

the residential populated areas, addresses concentrations oflead in soil, dust, paint, and 

water that exceed a specific set of trigger criteria. The purpose ofthis response action is to 

reduce the risk of lead exposure to children in Leadville and surrounding areas. Remedial 

actions taken within OU9 are intended to be consistent with the remedial action objectives 

and goals identified for the entire California Gulch Superfund Site and other OU 

investigations. 
The selected remedy for addressing residential populated areas is the Lake County 

Community Health Program (LCCHP), presented in the Final Feasibility Study 

(ASARCO, 1998) as Alternative 7. This is similar to the Lead Risk Reduction Program and 

the Kids First Program, described in the Consent Decree'. The Kids First Program is 

currently being implemented. The Selected Remedy combines blood lead monitoring, 

education, community awareness, and residence-specific response actions to reduce the risk 

of lead exposure to children in Leadville and surrounding residential areas. This program 

will address lead from soil and dust, interior or exterior paint, leaded plumbing fixtures, 

and other potential sources beyond an individual residence. 

The major components ofthe selected remedy include: 

• An extensive education and intervention program to manage lead exposure 

at the site. The education program will focus on raising public awareness 

about risks from lead and encourage participation in the Lake County 

Community Health Program. 

• Continued voluntary blood lead monitoring (with financial incentives, as 

appropriate) for all children age 6-72 months and voluntary blood lead 

monitoring for pregnant and nursing women. 

• Ifthe concentration of lead in blood of a child or a pregnant or nursing 

woman exceeds the blood lead criterion, or if the concentration of lead 

exceeds a specified set of trigger criteria for one or more of the environmental 

media at a residence, then appropriate actions will be taken to address the 

exceedance. These trigger criteria are summarized below: 

Blood Lead greater than or equal to 10 • g/dL 

Soil greater than or equal to 3,500 ppm 

Dust greater than or equal to 2,000 ppm 

Paint Interior or exterior paint, in poor 

condition, with the following lead levels: 

greater than or equal to 1 mg/cm^ 

Education 

greater than or equal to 6 mg/cm^ 

Active Remediation 

Tap Water greater than or equal to 15 * g/L 

•On August 25,1994, a Consent Decree between the United States, State of Colorado, ASARCO, Inc. (ASARCO) and 

Resurrection Mining Company was entered in U.S. District Court in Denver. Tlie Consent Decree defines areas of 

responsibility for these two companies as well as the U.S. 
• When one or more of the trigger criteria are exceeded, a range of different 

response actions, as provided in the Decision Summary, will be evaluated. 

The most appropriate response actions will be determined by evaluating the 

nature and extent ofthe exceedance, overall protectiveness ofthe action, 

compliance with applicable or relevant and appropriate requirements, 

long-term effectiveness and permanence, short-term effectiveness, 

implementability, cost-effectiveness, and community impacts. Views ofthe 

property owner will also be considered. No response action will be conducted 

without the permission ofthe property owner. 

• The selected remedy also includes institutional controls, discussed in detail in 

the Decision Summary, to ensure effectiveness of the LCCHP and to provide 

a notification system for property owners. 

• Since the LCCHP is considered a "pilot project" that involves a number of 

innovative approaches, it includes ongoing review to ensure, that the 

program is operating as intended and that human health is being adequately 

protected. In addition, the program will be evaluated by a group of outside 

scientists. And, as with any remedy where waste is left in place, EPA will 

conduct five-year reviews to ensure that the remedy is protective of human 

health and the environment. Any problems with the program will be 

identified and adjusted as necessary. 

STATUTORY DETERMINATIONS 

The Selected Remedy is protective of human health and the environment. It complies with 

federal and state requirements that are legally applicable or relevant and appropriate to 

the remedial action and is cost effective. Although this alternative does not satisfy the 

statutory preference for a remedy that employs treatment to reduce the toxicity, mobility, 

or volume of contaminants as a principal element, this remedy utilizes permanent solutions 

and alternative treatment (or resource recovery) technologies to the maximum extent 

practicable. Because this decision will result in hazardous substances remaining on site, 

above health-based levels, five-year reviews ofthis response action will be required. These 

reviews will be conducted during site-wide five-year reviews. The next five-year review is 

scheduled to be performed not later than February 2001. 

Max H. Dodson, Assistant Regional Administrator Date 7 

Environmenta] Protection Agency, Region Vm 
Data Certification Checklist 

The following information is included in the Decision Summary section ofthis Record of 

Decision. Additional information can be found in the Administrative Record file for this 

site. 

• Chemicals of concern (COCs) and their respective concentrations 

• Baseline risk represented by the COCs 

• Cleanup levels established for COCs and the basis for their levels 

• Current and future land and groundwater use assumptions used in the 

baseline risk assessment and ROD 

• Land and ground-water use that will be available at the site as a result of the 

Selected Remedy 

• Estimated capital, operation & maintenance (O4&M), and total present worth 

costs; discount rate; and the number of years over which the remedy cost 

estimates are projected 

• Decisive factor(s) that led to selecting the remedy 
DECISION SUMMARY 
TABLE OF CONTENTS 

Section Title Page 

L SITE NAME, LOCATION, AND DESCRIPTION 9 

n. OPERABLE UNIT AND ENFORCEMENT ACTIVITIES 9 

III. HIGHLIGHTS OF COMMUNITY PARTICIPATION 14 

IV. SCOPE AND ROLE OF OPERABLE UNIT 16 

V. SUMMARY OF SITE CHARACTERISTICS 17 

VI. SUMMARY OF SITE RISKS 20 

vn. REMEDIAL ACTION OBJECTIVES 22 

VIII. DESCRIPTION OF ALTERNATIVES 23 

DC. SUMMARY OF COMPARATIVE ANALYSIS 

OF ALTERNATIVES 26 

X. SELECTED REMEDY 29 

XI. STATUTORY DETERMINATIONS 35 

xn. DOCUMENTATION OF SIGNIFICANT CHANGES 36 

XIII. REFERENCES 37 

APPENDIX A - SITE LOCATION MAP, FIGURE 1 

APPENDIX B - RESPONSIVENESS SUMMARY 

APPENDIX C - APPLICABLE OR RELEVANT AND APPROPRIATE 

REQUIREMENTS (ARARS) 
DECISION SUMMARY FOR THE RECORD OF DECISION 

RESIDENTIAL POPULATED AREAS 

CALIFORNIA GULCH SUPERFUND SITE 

LEADVILLE, COLORADO 

L SITE NAME, LOCATION, AND DESCRIPTION 

The Califomia Gulch Superfiind Site (EPA ID #COD980717938) consists ofan approximately 

18.5-square-mile area that is part ofthe historic Leadville Mining District in Lake County, 

Colorado. This site is located in the Colorado Mineral Belt, a highly mineralized area ofthe 

Colorado Rocky Mountains. Ore mining, mineral processing, and smelting activities have 

produced lead, zmc, gold, and silver fi-om this world-class mineral deposit for more than 130 

years. 

The elevation ofthe California Gulch Site ranges from 9,448 feet at the confluence of Lake Fork 

Creek and the Arkansas River at the southwestem boundary ofthe site to over 12,000 feet above 

mean sea level near Ball Mountain east of Leadville, Colorado. Two parallel, north-south oriented 

mountain ranges, the Sawatch Range on the west and the Mosquito Range on the east, form a 

long, narrow valley in which the Residential Populated Area is located. Leadville is located on the 

eastem side ofthe valley created by these two mountain ranges. The eastem portion ofthe site is 

composed ofthe steep foothills ofthe Mosquito Range. The Califomia Gulch flows along the 

southem boundary of Leadville, passing to the north of Stringtown, and then flows 

west-southwest before entering the Arkansas River near the Lake Fork Trailer Park. 

This Record ofDecision (ROD) applies to areas ofthe Site that have been designated as Operable 

Unit 9 (OU9) Residential Populated Areas. These areas include portions ofthe site where the land 

use is residential or that are currently zoned as residential-populated areas and as low-density 

residential areas (Appendix A). The selected remedy is necessary to prevent the actual or the 

potential release oflead contamination which could impact public health. 

IL OPERABLE UNIT HISTORY AND ENFORCEMENT ACTIVITIES 

The Cahfomia Gulch Superfiind Site is located in and around the community of Leadville, 

Colorado, about 100 miles southwest of Denver. The Leadville area was the site of extensive 

mining, milling, and smehing operations beginning about 1860. Most ofthe facilities ceased 

operations around 1900, although several facilities continued operations into the 1920s (Westem 

Zinc) and the 1960s (AV Smelter) (Walsh, 1993). Nearly all ofthe mines within the Site 

boundaries are presently inactive, and all ofthe mills and smelters have been demolished. 
EPA placed the Site on the National Priorities List (NPL) in 1983 primarily due to concem over 

the impact of mine drainage on surface waters in the Califomia Gulch and the Arkansas River. 

Subsequent site investigations revealed the presence of heavy metals in soils and in waste piles in 

and around the current residential and commercial areas of Leadville. 

Numerous investigations have been conducted at the Site. These include remedial investigations 

conducted by EPA, the State of Colorado, Resurrection and ASARCO beginning as early as 

1986. Remedial investigations included determination of nature and extent of contamination in the 

following media: surface water, groundwater, air, tailings (both fluvial and impounded), waste 

rock, slag, and soils. Other remedial investigations which have been conducted include: metals 

speciation, aquatic ecosystem, terrestrial ecosystem, and the evaluation of sources oflead in and 

around residential homes. Current activities at the Site include completion of feasibility studies 

evaluating remedial altematives, remedial design, and constmction. 

A summary of enforcement activities at the site includes: 

On December 9, 1983, the State of Colorado filed an action for injury, destmction, 

or loss of natural resources associated with the release ofhazardous substances 

and the cost of assessment ofsuch injury from the Yak Tunnel and associated mine 

workings. The State amended its complaint on April 8, 1985, to include additional 

claims for reimbursement of costs incurred and to be incurred in response to the 

release or threat of release ofhazardous substances at the Yak Tunnel, associate 

mine workings, Califomia Gulch, and portions ofthe Arkansas River. 

On August 6, 1986, the United States of America filed an action seeking mjunctive 

relief for performance of responsibilities consistent with the National Contingency 

Plan (NCP) and for reimbursement of costs incurred and to be incurred by the U.S. 

in response to the release or threat of release ofhazardous substances at the Site. 

• On Febmary 3, 1987, the federal and state actions were consolidated into one 

proceedmg. 

• Counter-claims were asserted for contribution against both the United States and 

the State in this consolidated action. 

• On March 9, 1988, EPA issued a ROD selecting the remedial action for the Yak 

Tuimel Operable Unit. This ROD has subsequently been amended. The defendants 

are conducting this'work under a Unilateral Administrative Order (UAO) issued by 

EPA. 

10 
In response to a release, or a substantial threat of a release, ofhazardous 

substance(s) at or from the Site, EPA commenced (or administratively ordered 

various parties to commence) various remedial investigations and feasibility studies 

or other work consistent with the NCP: 

On September 28, 1990, EPA and the Settling Defendants entered into an 

Administrative Order on Consent (AOC) for the performance of soils sampling and 

air monitoring. 

On December 14, 1990, EPA and the Settling Defendants entered into an AOC for 

performance of site improvement activities at the Garibaldi Workings, the North 

Mike Workings, the Oregon Gulch Tailings Pond, and the Starr Ditch. 

On August 29, 1991, EPA issued a Unilateral Administrative Order (UAO) that 

required ASARCO to conduct studies and complete RIs related to the following: 

Demographics Work Plan; Final SampUng Plan for Sampling and Analysis of Lead 

Occurrence Within and Immediately Adjacent to Residences; Soil Investigation 

Work Plan; Mine Waste Pile Remedial Investigation; Tailing Disposal Area 

Remedial Investigation Work Plan and Surface Water, Bed Material and Aquatic 

Ecosystem Data Collection Program Work Plan. A First Amendment to this UAO, 

issued on October 8, 1991, required ASARCO to conduct and complete the 

Hydrogeologic Work Plan. A Second Amendment to the UAO, issued November 

21, 1991, required ASARCO to conduct and complete the Smelter Site 

Investigation Work Plan. A Third Amendment to this UAO, issued September 8, 

1992, required ASARCO to conduct and conplete the Work Plan for Terrestrial 

Ecosystems Evaluation. A Fourth Amendment to this UAO, issued on March 9, 

1993, required ASARCO to conduct and complete the pre-mining Soil 

Geochemistry Remedial Investigation (RI). The remaining work performed by 

ASARCO imder UAO 91-19, as amended was the final RI report for each ofthe 

above activities. 

To date, ASARCO has submitted fmal RI reports for Mine Waste, Tailing 

Disposal, Surface Water, Terrestrial Ecosystem Evaluation, Smelter Site Remedial 

Investigation, Hydrogeologic Remedial Investigation Report, Soil Inventory and 

Geology, with Data Amendments, Demographics Data Report, and Data Report 

for Lead Occurrence In/Adjacent to Residences. 

On September 10, 1991, EPA issued a UAO that required Resurrection Mining 

Company to conduct and complete the final Soils Investigation Work Plan. Field 

work under this UAO was completed in summer 1992. Resurrection submitted a 

fmal RI report to EPA pursuant to this UAO on July 15, 1994. 

11 
On September 12, 1991, EPA and the Hecla Mining Company ("Hecla") entered 

into an AOC for preparation ofan Engineering Evaluation/Cost Analysis 

("EE/CA") for the Stringtown/Malta Gulch Tailings portion ofthe Califomia 

Gulch Superfund Site. Pursuant to this AOC, Hecla was also required to detemiine 

the nature and extent ofany releases ofthe Malta Gulch Tailings and any 

appropriate response activities to address such releases. On January 6, 1993, a 

Partial Consent Decree between the United States and Hecla was entered by this 

Court. A fmal EE/CA was issued on August 2, 1993, for public review and 

comment. 

On December 3, 1992, EPA and The Denver & Rio Grande Westem Raihoad 

Company ("D&RG") entered into an AOC for the performance of a remedial 

investigation/feasibility study on lead slag piles and performance of specified 

studies on one zinc pile at the Califomia Gulch Superfiind Site. D&RG submitted 

the "Final RI Report for Lead Slag Pile Remedial Investigation" to EPA on 

December 4, 1993, and submitted a "Final Zinc Slag Pile Remedial Investigation" 

to EPA on December 11, 1993. 

On September 24, 1992, EPA entered into an AOC with ASARCO and 

Resurrection for performance of a metals speciation program. The Metals 

Speciation Data Report was issued in September, 1994 and updated in May 1996. 

A consent decree between the United States and D&RG was lodged with the 

Court on September 15, 1993, and entered on December 15, 1993. Pursuaat to the 

terms ofthis decree, D&RG paid a portion ofthe United States' response costs 

and agreed to conduct the remedial actions at the slag piles and raiboad yard and 

easement known as 0U3 (D&RG Slag Piles/Raihoad Easement/Railroad Yard). 

A proposed consent decree between the United States and Hecla addressing the 

Malta Gulch taihngs and Hecla's claims against the United States was lodged with 

flie Court in April 1994. 

A partial Consent Decree among the United States, the State, and the Settling 

Defendants settling the U.S. and the State's claim for their past response costs 

incurred prior to February 1, 1991, and Febmary 1, 1992, respectively, was 

entered by the Court on September 4, 1993. 

On August 25, 1994, a Consent Decree with ASARCO and Resurrection was 

entered in U.S. District County in Denver. The Consent Decree defined areas of 

responsibility for these two companies as well as the U.S. Govemment. 

12 
A summary of interim actions at the site includes: 

An Engineering Evaluation/Cost Analysis work plan was prepared in November 1994 (ASARCO, 

1994) to evaluate lead concentrations in soils within parks and playground areas in 0U9. Based 

on the finding that soils at all identified play areas were below the trigger level of 3500 ppm lead, 

EPA approved no fiirther action for the areas addressed by the work plan. Subsequently, one 

additional play area was identified on East 6*" Street at St. Patrick Street. Soils at this play area 

exceeded 3500ppm lead in soil so this area requires remediation. Contaminated soils will be 

excavated, disposed ui a suitable repository, and replaced with clean fill. 

An Engineering Evaluation/Cost Analysis was prepared m 1995 (ASARCO, 1995) to evaluate 

removal action altematives for 38 mine waste piles identified in the populated areas of eastem 

Leadville, within OU9, in accordance with the ASARCO Work Management Plan (WAMP) 

(Appendix B to the Consent Decree). An Action Memorandum issued by the EPA in August 1996 

selected a non-time-critical removal action requiring the removal of 14 piles with surface lead 

concentrations greater than 3,500ppm. Removal of these piles prevents direct exposure to high 

lead concentrations and protects surface water by removing the potential for transport of metals 

away from the source area and, therefore, reduce metals impact to surface water or other areas. 

Implementation ofthis removal action began in 1997 with the removal of four mine waste piles. 

The removal ofthe remaining ten mine waste piles is scheduled for 1999. The selected removal 

action is consistent with the performance ofthe final remedial action selected for 0U9 and will be 

considered as the fmal remedy for mine waste piles within 0U9 when conplete. 

The Kids First Program is an interim response program designed to address sources of 

environmental lead at individual residential properties withui 0U9 (Woodward Clyde Consultants, 

1994). The program has been implemented by ASARCO, with assistance from Lake County, since 

1995. This voluntary program targets households with children under 6 years old and includes 

blood lead monitoring, testing of potential environmental sources oflead, and, when necessary, 

the development and implementation of risk-based response actions to reduce significant lead 

risks in and around the home. Lake County performs the blood lead monitoring and some 

education components ofthe program. Since 1995, soil remediation has been performed at 37 

properties m accordance with Action Memorandums prepared for each property. In addition, dust 

abatement has been performed at 16 properties, paint remediation performed at 6 properties and 

drinking water addressed at 2 properties. All actions and no-action determinations have been 

developed and approved by the Kids First work group and accepted by the property owner. All 

interim response actions for paint, drinking water, and soil perfomied under the Kids First 

Program are considered consistent with the final remedial action selected for OU9. 

13 
IIL HIGHLIGHTS OF COMMUNITY PARTICIPATION 

Throughout EPA's work at the Califomia Gulch Superfiind Site, contact with members ofthe 

community has been maintained through public and neighborhood meetings, open houses, 

briefings for local officials, press releases, fact sheets, and other informal communication. EPA 

and the other parties involved in the Superfiind project have also established local offices in 

Leadville so the community can speak directly with the project representatives. 

Commimity groups are an important component ofthe community relations effort at the 

Cahfomia Gulch Superfimd Site. The Lake County Environmental Task Force (LCETF) is an 

open membership group of individuals interested in environmental issues in the Lake County area. 

The LCETF obtained a $50,000 technical assistance grant from EPA that enables the group to 

hire consultants and technical experts. These experts comment on technical documents and 

evaluate the scientific data on the Site for the community. 

EPA's community relations activities at the Site included a series of risk assessment workshops 

conducted for community leaders and health professionals. In addition, a lead awareness program 

was begun in Febmary 1990 to teach parents and children about the hazards oflead. 

Several groups have formed as a resuh ofthe Superfimd activities in Leadville. These groups 

provide opportunities for the citizens to take an active role in the consultation and decisionmaking process for the Site. A brief description of each of these groups is provided below. 

• Technical Assistance Committee. The Technical Assistance Committee (TAC) 

was formed m 1991 and provides a forum for community representatives, 

companies working at the site, EPA, the State of Colorado, and their technical 

experts to discuss and evaluate the technical issues related to the Site. TAC 

meetings are open to the pubhc and are held in Leadville and Denver. Any TAC 

member may call a meeting and prepare an agenda for discussion. Minutes from 

the TAC meetings are made a part ofthe Administrative Record for the Site. 

• Site Activities Coordinating Committee.The Consent Decree between the 

responsible parties at the Site recognized that different groups would be working 

on various remediation projects at the same time. The parties doing remediation 

want to ensure that their work does not mterfere with the numerous civic and 

tourism events in town. In order to coordmate these work efforts with civic events, 

a Site Activities Coordmating Committee (SACC) was formed. The members of 

the committee meet with representatives from the City and Coimty monthly (or 

as-needed) to coordinate all on-gomg and pending Site activities and to mmimize 

dismption to the community. 

14 
• Kids First Work Group. The Kids First Work Group, formed in 1994, provides 

direction for the Kids First Program. Public health officials and representatives of 

the City of Leadville, Lake County, State of Colorado, ASARCO, and EPA each 

have membership in the Kids Fhst Work Group. The Work Group oversees the 

development of informational materials and plans, and monitors and evaluates the 

progress of activities being implemented under the Kids First Program. 

Extensive outreach efforts by both the Lake County Health Department and ASARCO have 

played a key role in the implementation ofthe Kids First Program. The program began with a 

public meeting on May 25, 1995. Newspaper advertising introduced the program and continues 

with weekly lead education "tips" for residents and encouragement for blood lead testing of 

children under 72 months and pregnant/nursmg women. Information to promote safe remodeling 

tips is displayed at local hardware stores. Door to door contacts were made to recmit families in 

areas with soil lead concentrations estimated at or above 3,500 ppm in 1995, 1996 and 1997. 

Presentations have been made to community groups to explain the Kids First Program. 

Educational sessions have also been conducted at public daycare centers, private licensed day care 

centers and at the elementary school. Periodic updates continue at these facihties and educational 

brochures are available both for the child-care providers and the families they serve. The program 

has also worked with other preschool groups to combine efforts. The Health Department works 

with the immunization program and the Head Start and Women, Infants and Children (WIC) 

organizations to recmit children for blood lead testing. Reminder cards are mailed to families to 

encourage annual blood lead screening. 

The LCCHP will continue similar outreach efforts and may pursue altemate outreach approaches 

as new ideas develop or as needed to maintain awareness and participation. 

All ofthe information upon which selection ofthis remedy is based is included m the 

Adniinistrative Record. The Administrative Record is available for review at both the Lake 

County Public Library and the Colorado Mountain College Library in Leadville and at the EPA 

Superfiind Records Center in Denver. 

The public reviewed the Proposed Plan associated with this ROD. Public comments and EPA's 

responses are included as Attachment A. 

15 
IV. SCOPE AND ROLE OF OPERABLE UNIT 

The Califomia Gulch Superfimd Site is divided mto twelve media and geographically-based 

operable units (OUs) within the Site. These OU's are designated as: 

OUI - Yak Tunnel/Water Treatment Plant 

0U2 - Maha Gulch Fluvial Tailing/Leadvil le Corporation Mill/Malta Gulch Tailuig 

0U3 - Denver & Rio Grande Raikoad Slag Piles/Railroad Easement/Railroad Yard 

0U4 - Upper CaUfomia Gulch 

0U5 - ASARCO Smelters/Slag/Mill Sites 

OU6 - Starr Ditch/Penrose Dump/Stray Horse Gulch/Evans Gulch 

0U7 - Apache Tailing Impoundments 

OUS - Lower Califomia Gulch 

OU9 - Residential Populated Areas 

OUIO -Oregon Gulch 

OUI 1 - Arkansas River Valley Floodplain 

OUI2 - Site Water Quality 

This Selected Remedy for 0U9 addresses concentrations oflead in soil, dust, paint and water that 

exceed a specified set of trigger criteria. Exceedance of these criteria could pose a threat to 

human health, specifically in children age 0-72 months. The purpose ofthis response is to reduce 

the risk oflead exposure to children in Leadville and surrounding areas. Remedial actions 

undertaken within 0U9 are intended to be consistent with the remedial action objectives and goals 

identified for the entire California Gulch Superfimd Site and other OU investigations. 

This decision document makes no detemiination on whether surface water or groundwater within 

0U9 requires remediation. Pursuant to the August 25, 1994 Consent Decree at this Site, it was 

agreed that the decision on remediation of surface water and groundwater site-wide (Operable 

Unit 12) would be made only after records of decision for source remediation were selected and 

implemented at each operable unit. As a resuh, specific water quality goals for surface streams 

and groundwater have not been established at this time. 

16 
V. SUMMARY OF SITE CHARACTERISTICS 

1. Climate and Meteorology 

The LeadviUe area has an alpine climate that is ofthe semi-arid, continental type. The average 

armual precipitation is 17.53 inches with the wettest months being July and August and driest 

months being December and January. The normal temperature exfremes range from 86* F to 

-30» F with an average aimual air temperature of 36.2* F. The lowest temperatures occur in 

January, and the highest temperatures are m July and August. Based on RI data, the maximum 

hourly average wind speed ranges from a minimum of 9 miles per hour (mph) in October to a 

maximum of 20.4 mph occurring m December; however, wind gusts in excess of 50 mph do 

occur. Wind is predominantly from the northwest. 

2. Surface Water Hydrology 

The Cahfomia Gulch drains approximately 7,400 acres of watershed into the Arkansas River. The 

mam stream ofthe Gulch receives water from several ephemeral drainages that mclude Stray 

Horse Gulch, Starr Ditch, Upper CaUfomia Gulch, Oregon Gulch, Georgia Gulch, and Pawnee 

Gulch (CH2M Hill, 1987). Discharges are also received from the Yak Tunnel through the Yak 

Water Treatment Plant, and from the Leadville Sewage Treatment Plant. 

3. Geology 

The geology ofthe Leadville Mmmg District and surrounding area is complex and weU 

documented. The elevations in the study area range from 9,350 feet at the lower Arkansas River 

floodplain to over 14,000 feet at the eastem edge ofthe Leadville Mming District drainage (crest 

ofthe Mosquito Range). In general, the topography is mgged on the westem slope ofthe 

Mosquito Range. Timberline is approximately 11,850 feet. The region bears the 

geomorphological features resuhing from Pleistocene glacial activity. 

Bedrock in the Leadville area consists of Precambrian granite and metamorphic rocks overlain by 

quartzite, limestone, dolostone, siUstone, sandstone, and shale of Paleozoic, Mesozoic, and 

Cenozoic age. Intmsive rocks include porphyry dikes and sills of Tertiary age. The upper 

Cambrian Sawatch quartzite unconformable overlies the Precambrian rocks. This quartzite is 

approximately 60 feet thick. It is overlain by 45 feet of shaley beds of late Cambrian Peerless 

formation. Ordovician age Manitou Dolomite uncomformably overlays the Peerless formation. 

Above this is the Devonian Chaffee formation. These rocks are exposed in the upper reaches of 

the Mosquito Range as well as in the hills east of Leadville. The Leadville limestone (dolomite) of 

Mississippian age is exposed in Leadville and along some sections of lower CaUfomia Gulch. 

17 
A system of major and minor faults cause significant displacement (100 to 1,000 feet) and 

fracturing of bedrock in the area. Faults in the bedrock are generally high-angle northerly-striking 

fracture zones. Blocks of bedrock between major faults are commonly broken by numerous minor 

faults and fissures (Emmons et al, 1927). The Pendery Fauh marks the boundary between upper 

and lower Califomia Gulch. The Pendery Fault, which trends north-south across Califomia Gulch, 

has caused the lower gulch to be filled with thicker deposits of alluvium. These alluvial deposits 

are mterspersed with thin, interglacial, silty clay lake bed deposits. 

The Leadville area is underlain by alluvial deposits and unconsohdated glacial outwash materials 

of Pleistocene age. These materials include porphyry, rhyolite, granite, and other igneous rocks, 

quartzite, dolomite, limestone, and sandstone. These materials were transported and redeposited 

by glacial and fluvial processes. The vertical and lateral extent of these alluvial deposits is not well 

defmed. The Arkansas River Valley is composed of Holocene sfream terrace, stream channel, and 

flood plain deposits. 

4. Hydrogeology 

Groundwater in the Leadville Mining District occurs in both bedrock and aUuvial aquifers. The 

bedrock aquifer consists of Precambrian granite overlain by quartzite, porphyry dikes, sandstone, 

dolostone, and Umestone of Paleozoic age. Groundwater movement is faciUtated by permeable 

highly-fi^ctured zones adjacent to major interconnections minor faults, intergranular rock 

porosity, and mine workings. PermeabiUty is generally low. 

Groundwater in the alluvial aquifer is contained in Tertiary and Quatemary lake bed, glacial 

outwash deposits, and sfream and terrace deposits. The alluvial aquifer occurs in two stratigraphic 

units, an upper unit and a lower unit. The alluvial deposits are considered to be hydraulically 

connected with the bedrock aquifer through contact, faulting, fracturing, and extensive mining 

activities. Recharge to the bedrock and alluvial aquifers results from infilfration of precipitation 

and surface water. 

5. Land Use and Demography 

The Califomia Gulch Superfiind Site, mcludmg the town of LeadviUe, is located m Lake County, 

Colorado. Lake County is a relatively small (380 square miles), predominantly rural county with a 

1990 population of 6,007 (U.S. Bureau ofthe Census, 1990). Persons residing within the 

LeadviUe city Umits account for approxunately half of the county's total population. 

The population of Lake County has fluctuated with the mining industry. Population peaked at 

18,054 m 1890, declined to below 7,000 in 1920, and remained generally at that level until 1960. 

18 
During the years between 1960 and 1981, population graduaUy mcreased to approximately 9, 000 

and then declined throughout the 1980s. The closure of AMAX's Climax molybdenum mine in 

1981 and its reduced level of operations upon reopening were major factors contributing to the 

decline. Leadville's population trends have been similar to those of Lake Coimty. 

Approximately two-thfrds ofthe land m Lake County is federally owned. Most ofthe federal land 

is within the San Isabel National Forest, with the Bureau of Land Management managing most of 

the remainder. However, most land in the LeadviUe Mining District is privately owned. 

Land uses surrounding CaUfomia Gulch are predominantly mining, commercial, and residential. A 

small area of rangeland in the LeadviUe area is directly upstream from the confluence of Califomia 

Gulch and the Arkansas River. 

Human receptors, potentially exposed to Site contaminants, include the residential population. 

Recreational/commercial exposures in OU9 have been detennined to be msignificant (WESTON. 

1996c). 

6. Results ofthe Remedial Investigations 

Soils are the primary pathway of exposure to the residential population at the site. Lead has been 

determined to be the only contaminant of concem in 0U9. This discussion will focus on soils in 

the 0- to 6-inch depth interval on which the risk assessment is based. 

The extreme heterogeneity of surface soils (0- to 1 -mch) in Leadville and Stringtown is also 

characteristic of soil lead concentrations in the 0- to 6-inch near-surface composite soils found in 

the Leadville and Stringtown communities and in the Lake Fork Trailer Park (Figure 2). This 

variability in lead concentrations can be attributed to the fact that these soils have been impacted 

to varying degrees by historical smelter emissions and mimng wastes. 

In aU soils, the lead concentrations typically decrease with soil depth (Walsh, 1992a). However, 

lead concentrations ui deep disturbed soils that are higher than the concentrations ui the overlying 

disturbed surface soil have been reported m some locations (CDM, 1994; Walsh, 1993). This is 

most likely due to the intermixing of soils with mine wastes of highly variable lead content. The 

lead concentrations in surface soils and the concentrations oflead at specific soil depth intervals 

are discussed in the Soils Investigation and mapping Report (Walsh, 1992a). There is a lead 

concentration gradient observed in near-surface soil within LeadviUe that has an east-west 

orientation, with the maximum lead concentrations appearing in the east, due to historical mining 

activities, and dropping in the westward direction. 

19 
The old Downtown Leadville Nfming District (Emmons, 1907) located in the eastem part of 

LeadviUe, was found to contain the highest lead concentrations. The soil-lead concentrations in 

this area and m the southeastern part of Leadville are likely to exceed 3,500 ppm. Soil-lead 

concenfrations are also lUcely higher in Stringtown, where lead concentrations in the 0- to 6-inch 

depth interval typically range from 2,000 ppm to greater than 3,500 ppm. In addition, some areas 

at the north and south ends ofthe Lake Fork Trailer Park are likely to contain soil with elevated 

lead concentrations. 

VI. SUMMARY OF SITE RISKS 

During the soils remedial investigation, a baseline human health risk assessment was performed to 

estimate the probability and magnitude of potential adverse human heaUh and envfronmental 

effects from exposure to hazardous substances associated with the Site. The human heahh risk 

assessment foUowed a four-step process: 

1. Contaminant Identification, which identified those hazardous substances of 

potential health concem; 

2. Exposure Assessment, which identified actual or potential exposure pathways 

(routes where people contact the chemicals), characterized the potentially exposed 

populations, and determined the extent of possible exposure; 

3. Toxicity Assessment, which considered the types and magnitude of adverse health 

effects associated with varying amounts ofthe hazardous substances of concem; 

and, 

4. Risk Characterization, which integrated the three previous steps to summarize 

the actual current and fiature potential risks posed by exposure to hazardous 

substances at the Site. 

Part A ofthe human health risk assessment (WESTON, 1996a) examined risks to residents from 

lead, focusing specifically on risks to young children (age 0 to 6 years). Children were selected as 

the focus ofthis risk assessment because children typically have higher intake rates per unit body 

weight of envfronmental media than aduhs, children tend to absorb a higher fraction of ingested 

lead from the gasfrointestmal tract than do aduhs, and children tend to be more susceptible to 

some ofthe adverse effects oflead than aduhs (especiaUy impairment ofthe nervous system). 

Part B ofthe human health risk assessment (WESTON, 1996b) concluded that there are no 

locations on site where antimony, barium, cadmium, beryllium, chromium, copper, mercury, 

nickel, silver, thallium, or zinc are of significant concem in soil. The risk assessment also 

20 
concluded that based an the fact that risk exceedances are smaU for arsenic and manganese and 

occur only in the most conservative risk calculations, combmed with the recognition that the 

assumed uptake (bioavaUabUity) of metals used in the calculations may be higher than actual, that 

non-lead metals (including arsenic and manganese) in surface soils do not pose a significant health 

risk to residents. Thus, the only contaminant of concem is lead. 

Risk Assessment Approach for Lead 

The risk assessment for lead was supported by a large body of site-specific data that included not 

only extensive measurements oflead in soil and dust in residential locations, but also an extensive 

demographics survey, data on lead levels m water and paint (both interior and exterior), data on 

the physical and chemical forms of lead at various locations around the community, and an 

informative community-wide blood lead study involving 314 children ( about 65% ofthe total 

population of children at the site). These data were used to support two paraUel lmes of 

investigation and assessment. The first of these employed EPA's Integrated Exposure Uptake and 

Biokinetic (lEUBK) model to calculate the expected impact of lead levels m soil and dust on 

blood lead levels in area children. The second approach compared the measured blood lead values 

in area children with relevant national blood lead statistics in order to help evaluate the current 

effects of actual site exposure to lead. 

The main findings ofthe lead risk assessment for residential children are summarized below: 

1. In 1991, geometric mean blood lead levels in children livmg within the site boundaries 

were typically around 5-6* g/dL, which was about 1-1.5 • g/dL higher than reported 

geometric mean values for children of similar age and sex livmg m other areas across the 

nation. 

2. In 1991, the site-wide frequency of children exceeding the CDC's health-based blood lead 

target of 10 • g/dL was about 8%, which is slightly higher than the target of no more than 

5% above 10 • g/dL. This was indicative of a situation which exceeded EPA's goal of no 

uidividual child or group of similarly exposed children having a greater than 5% chance of 

exceedmg a blood lead level of 10 • g/dL. In some sub-areas ofthe site, the risk of 

exceeding 10 • g/dL appeared to be substantially higher (10%-25%) than the site-wide 

average. Additional blood lead data collected by coimty health agency from more than 100 

children per year for each year between 1991 and the present suggests that the incidence 

of children in the commimity with blood lead levels above 10 • g/dL is continuing to 

fluctuate between 6% and 9%. 

3. There is a statistically significant correlation between lead levels ranging from 3,000ppm 

to 3,500 ppm m soil and dust and elevated blood lead levels in children. 

21 
4. Both interior and exterior leaded paint contribute to risk of elevated blood lead levels in 

children, mainly by addmg to the concenfration oflead in soil and/or dust m those homes 

where lead-based paint is a potential source oflead exposure. 

5. The resuhs ofthe lEUBK model run using defauh soil and dust ingestion rates predicted 

blood lead levels that were higher than observed. It was concluded that soil and dust 

ingestion rates in this community were probably somewhat lower than the national average 

values, possibly because the ground is frozen or snow-covered approximately eight 

months out ofthe year. Local efforts to minimize lead exposure through an extensive 

education and intervention program might also explain some ofthe variation in predicted 

versus currently observed blood lead levels. 

6. Based on the analyses conducted, the risk assessment reached the conclusion that soil lead 

is a relatively minor source of exposure at locations where lead levels were less than about 

1,000 ppm. Exposure via soU probably did not become a dominant source of exposure 

until lead levels were above the range from 3,000ppm to 3,500 ppm. Other sources oflead 

contributing to current exposure included interior and exterior paint and indoor dust. Lead 

levels in the water supplied by the mimicipal water system are not of concem, but lead 

levels in some portions ofthe shallow aquifer are high enough that it would not be safe to 

use that groundwater as a routine source of drinking water. 

VII. REMEDIAL ACTION OBJECTIVES 

EPA guidance (EPA 1994) statesthat EPA should: 

...limit exposure to soil lead levels such that a typical (or hypothetical) [potentially 

exposed] child or group of similarly exposed children would have an estimated risk of no 

more than 5% of exceeding the 10 • g/dL blood lead level. 

In accordance with this policy recommendation, the Remedial Action Objectives (RAOs) at this 

Operable Unit agreed to in the Consent Decree (U.S. District Court, 1994) are as follows: 

• RAO- 1: "No more than five percent of aU children (age 0 to 72 months) who live at this 

site, either now or in the future, will have blood lead values higher than 10 • g/dL blood 

lead level." 

RAO-2: "HeaUh will be adequately protected ifthe highest risk level at any sub-location 

(e.g., a yard or home) is a probability no higher than one percent that a population of 

children (age 0 to 72 months) residmg at that sub-lo.cation will exceed a blood lead value 

of 15 "g/dL." 

22 
RAO-1 and RAO-2 were used to guide the risk management process for OU9. Based upon the 

Part A human heahh risk assessment (WESTON 1996a), which considered both measured and 

predicted blood lead levels, it was determined that RAO-1 and RAO-2 may not be satisfied unless 

remedial actions are implemented to reduce exposure and risk. Accordingly, a Feasibility Study 

(FS) was conducted to develop and evaluate appropriate remedial action altematives. 

The FS then added the following additional RAO: 

• Reduce the dfrect exposure of lead incurred by children, which will result in optimal risk 

reduction through effective use of resources. 

III. DESCRIPTION OF ALTERNATIVES 

A Screening Feasibility Study (SFS) was prepared by EPA, for the purpose of identifying and 

screenmg potentially applicable technologies, as well as general remedial altematives for each 

source. Potential technologies/process options were screened on the basis of effectiveness to 

achieve remedial objectives, technical and adniinistrative feasibility, and cost. Those technologies 

or process options that were retained are: no action, deed restrictions, fencing and posted 

wamings during constmction, mformation and educational programs, diversion ditches, 

channelization, m-site mixmg, revegetation, simple cover, mechanical excavation, tmck hauling, 

on-site repository, and on-site consolidation. An additional remedial ahemative, the Lake County 

Community Health Program (LCCHP), proposed by Lake County, was also retamed for 

consideration m the Feasibility Study. Two options were eUminated in the uiitial screening 

analysis. These were soil washing and in situ stabilization. Soil washuig was not retained as an 

option because implementation time would be lengthy, and capital and operation/maintenance 

costs would be high. In situ stabilization was not retained as an option because of high capital and 

high operation/maintenance costs. 

Seven remedial altematives were analyzed for 0U9 (ASARCO, 1998). A description of each of 

these ahematives is provided below. In each case, 12 years of implementation was identified to 

simplify cost conparison between altematives. The discoimt rate is equivalent to the rate of 

escalation of future costs, or the mflation rate. It is anticipated that most ofthe expense wiU occur 

in the first twelve years. In each case (with the exception of No Action) the remedy will be 

implemented until performance standards have been satisfied. The duration of a remedy may 

exceed 12 years m order to meet perfomiance standards. For example, institutional controls 

would be on-going. 

Alternative 1: No ACTION. 

23 
Capital Cost: $0 

Operation & Maintenance: $0 

Years of Implementation: None 

The Superfimd program requfres that the "no action" altemative be evaluated to establish a 

baseline for comparison. Under this alteraative, EPA would take no further action at the She to 

reduce the risk of exposure to lead. 

Alternative 2: INSTITUTIONAL CONTROLS 

Capital Cost: $128,940 

Operation & Maintenance: $0 

Years of Implementation: 12 

Institutional controls (ICs) may include zoning/deed restrictions, permitting requfrements, 

temporary access restrictions, and commimity awareness education. Deed restrictions could 

legally liinit or prohibit future land use in the source area. ICs alone may be an appropriate 

remedial action altemative for some residential area soils source sites. This altemative may also be 

an element of other ahematives; if so, temporary access restriction such as fencing and posted 

wamings would only be used to physically control access to the residential area soils during 

constmction activities. 

Alternative 3: CONTAINMENT (SURFACE WATER CONTROL)/ICS 

Capital Cost: $432,180 

Operation & Mamtenance: $ 187,020 

Years of Implementation: 12, or until performance standards are achieved 

Altemative 3 for the residential area soils includes the ICs described in Altemative 2 combmed 

whh surface water containment. The contauiment component ofthis altemative includes surface 

water confrol methods such as diversion ditches and culverts. The diversion ditches would be 

constmcted to divert surface water flow and run-on away from and around the source areas. 

Covered culverts would be constmcted to conduct surface water flow through more populated 

areas. These confrols would reduce the potential for transport of metals away from the source 

area and, therefore, reduce metals impacts to surface water or other areas. Operation and 

maintenance requirements would include maintenance of ditches and culverts, modification of 

deeds, permit processing, and educational activities. 

24 
Alternative 4: CONTAINMENT (SOURCE SURFACE CONTROL)/ICS 

Capital Cost: $868,640 

Operation & Mamtenance: $308,220 

Years of Implementation: 12, or until performance standards are achieved 

This altemative includes the ICs described in Altemative 2 combined with methods for source 

surface containment. The containment component ofthis altemative would be based on source 

surface control options mcluding soil covers, in situ mixing, and revegetation. Soil cover involves 

adding additional fill to isolate the impacted surface soil. In situ mixing involves tilling surface soil 

with deeper soil to reduce surface soil lead concentrations to acceptable levels. Revegetation 

involves planting appropriate cover vegetation to lessen infiltration, leaching, and erosion. 

Operation and maintenance requfrements would include maintenance of vegetation, ditches and 

culverts, modification of deeds, permit processing, and educational activities. 

Alternative 5: CONTAINMENT (SURFACE WATER CONTROL, SOURCE SURFACE 

CONTROL)/ICS 

Capital Cost: $1,291,450 

Operation & Maintenance: $308,220 

Years of Implementation: 12, or until performance standards are achieved 

Aheraative 5 for the residential area soils sources includes the ICs described in Altemative 2 

combined with containment of both surface water and source surfaces. Surface water control may 

be implemented through diversion ditches and culverts as discussed in Altemative 3. The source 

surface control element of containment involves in situ mixuig, revegetation, or a soil cover as 

discussed m Altemative 4. Operation and maintenance requfrements would mclude maintenance 

of vegetation, ditches and culverts, modification of deeds, permit processing, and educational 

activities. 

Alternative 6: REMOVAL/TRANSPORTATION/DISPOSAL/ICS 

Capital Cost: $6,029,894 

Operation & Mauitenance: $281,760 

Years of Implementation: 12, or until performance standards are achieved 

This ahemative includes the ICs described ui Altemative 2 combmed with removal, transport, and 

disposal of residential area soils where mean lead levels are greater than 3,500. The residential 

area soils would be excavated by hand with the aid of small conventional earth-moving equipment 

and replaced with clean fill. Excavated materials would be hauled by tmck to an on-site 

25 
repository, consolidated in an existing on-site tailmgs pile, or removed to some other designated 

area. Upgradient areas might also requfre remediation to prevent re-contamination. Operation and 

maintenance requfrements would mclude mauitenance of vegetation, ditches and culverts, and 

educational activities. 

Alternative 7: LAKE COUNTY COMMUNITY HEALTH PROGRAM 

(Selected Altemative) 

Capital Cost: $3,106,800 

Operation & Mauitenance: $ 1,732,450 

Years of Implementation: 12, or until performance standards are achieved 

Altemative 7 is implementation ofthe Lake County Community Health Program (LCCHP). The 

program combines blood lead monitoring, education, community awareness, and residencespecific response actions to reduce lead exposure to children in Leadville and surrounding areas. 

This program wiU address lead from soil and dust, interior and exterior paint, leaded plumbing 

fixtures, and other potential Sources beyond an individual residence. Altemative 7 wiU also 

include institutional confrols to ensure effectiveness ofthe LCCHP. Operation and maintenance 

activities would include LCCHP administration and the blood lead monitoring program. 

IX. SUMMARY OF COMPARATIVE ANALYSIS OF ALTERNATIVES 

The following section ofthe ROD compares the selected altemative and the other altematives 

using the nine evaluation criteria as described m the FeasibiUty Study (ASARCO, 1998). 

OveraU Protection of Human Health and the Envfronment 

Altemative 7 will provide the most comprehensive protection of human health and the 

envfronment from lead, since it addresses not only lead in soU but also lead in other sources such 

as dust. Ulterior and exterior pamt, and drinking water. Altematives 5 and 6 provide less 

protection since they do not address all lead sources. Alteraatives 3 and 4 provide fafr protection 

since they address surface water contamination, but do not address multiple sources oflead. 

Altemative 2 would provide fafr to poor protection. Institutional controls may be sufficient m 

some cases to protect human health, but this altemative would not manage surface water. 

Altemative 1 provides no protection. 

26 
Compliance with ARARs 

Applicable requfrements are defmed by the NCP as those cleanup standards, standards of confrol, 

and other substantive envfronmental protection requfrements, criteria, or limitations promulgated 

under federal or state law that specifically address a hazardous substance, poUutant, contaminant, 

remedial action, location, or other cfrcumstances at a site. It should be noted that while a 

requfrement may not be applicable as a matter of law, a requirement may stiff be "relevant and 

appropriate" if it regulates or addresses problems or situations sufficiently similar to those 

encountered at the subject site that its use is well-suited to the particular site. ARARs are grouped 

into three categories: chemical-specific, action-specific and location-specific. Altemative 1 does 

not satisfy selected ARARs except m areas with an acceptably low risk for lead exposure. 

Location-specific ARARs would be addressed under Alteraative 2. Institutional controls would 

provide some protection to the community from dfrect exposure. Under Altematives 3, locationspecific and chemical-specific ARARs would not be addressed where sources remain in thefr 

existing condition. Action-specific ARARs would be partially satisfied through storm water 

controls. For altemative 4, chemical-specific and location-specific ARARs would be addressed. 

Action-specific ARARs would be partially addressed except for storm water control. Ahematives 

5, 6, and 7 would comply with all ARARs. 

Long-Term Effectiveness and Permanence 

Alteraative 1 does not reduce residential risk, while Altemative 2 could be somewhat effective by 

controllmg/limiting fiiture use. Alteraatives 3, 4, and 5 provide a moderate degree of long-term 

effectiveness, but recontammation is likely and these alteraatives do not address all lead sources. 

Altemative 6 would provide the highest degree of long-term effectiveness and permanence for 

soils; however, it does not address other potential lead sources and would requfre long-term 

operation and maintenance ofan on-site repository. Aheraative 7 would provide long-term 

effectiveness for many lead sources. 

Reduction of Toxicitv. Mobility, or Volume Through Treatment 

None ofthe alteraatives reduce toxicity, mobiUty or volume through treatment. 

Short-Term Effectiveness 

Alteraative 1 has no short-term effectiveness. Alteraative 2 would be somewhat effective by 

controlling use of some source areas. Ahemative 3 could have good short-term effectiveness m 

reducmg the potential for surface water impacts. Altematives 4, 5, and 6 pose higher relative 

27 
short-term risks to residents and workers compared to other altematives by virtue of disturbing 

contaniinated surface soils. Altemative 7 would have the greatest overall short-term effectiveness 

by prioritizing intervention and remediation in cases of children with elevated blood lead levels 

coupled with proactive identification and abatement ofthe most significant sources oflead 

exposure m residential areas. 

Implementability 

Altemative 1 does not requfre unplementation. Commimify Protective Measures (Altemative 2) 

would be easy to implement; however, the administrative aspects such as deed restrictions could 

pose difficulties m enforcement. Altemative 3 would be relatively simple to implement smce most 

ofthe surface water controls could be implemented on public land or easements. Altematives 4 

and 5 would be relatively easy to unplement except for access and space limitations. Alteraative 6 

would be difficult to unplement due to space constrictions m most residential yards. Alteraative 7 

could be more easily implemented because the framework for the Lake County Community 

Health Program (LCCHP) is currently in place, a trust fund has been estabhshed to pay for its 

operation, and the implementation would be an extension ofthe current Kids First Program. 

Cost 

Alteraative 1 has no associated cost. Ahematives 2 and 3 have a relatively low cost, but do not 

satisfy the remedial objective. Altematives 4 and 5 are moderately priced, but do not satisfy the 

remedial objective. Aheraative 6 is the highest cost aheraative, but does not address all the 

sources oflead. Alteraative 7 would satisfy the remedial objective at a moderate cost as compared 

to other ahematives. 

Support Agencv Acceptance 

The Colorado Department of Public Health and the Envfronment has participated ui the decisionmaking process and concurs with the implementation of Altemative 7 since residential soils and 

additional sources oflead would be controUed. 

Community Acceptance 

Based on public comments received on the LCCHP proposal, the Community appears to accept 

the preferred ahemative. (See Appendix B for public comments and EPA's responses.) Altemative 

7 (LCCHP) has the support of Lake Coimty public health officials and the CDPHE, as well as 

elected representatives from both the City of Leadville and Lake County. Commimity 

participation in, and strong support for the Kids Ffrst Program also indicates community 

acceptance. 

28 
X. SELECTED REMEDY 

Based upon consideration ofCERCLA requfrements, the detailed analysis of ahematives and 

public comments, EPA has determined that the LCCHP alteraative presented in the Final 

Feasibility Study (ASARCO, 1998), as modified below, is the appropriate remedy for residential 

populated areas hi 0U9. 

Alternative 7: Lake County Community Health Program 

Description 

Altemative 7, the LCCHP (similar to the Lead Risk Reduction Program defined ui the WAMP 

[ASARCO 1994]), integrates a variety oflead intervention methods. The LCCHP combmes blood 

lead monitoring, education, community awareness, and residence-specific response actions to 

reduce the risk oflead exposure to children in Leadville and surrounding residential areas. This 

program wiU address lead from soil and dust, ulterior and exterior paint, leaded plumbing fixtures, 

and other potential sources beyond an individual residence, 

An extensive education and mtervention program to manage lead exposure at the site is an 

integral part ofthe remedy. The education program will focus on raising public awareness about 

risks from lead and encourage participation in the Lake County Community Health Program. 

Education will mclude uidividual face-to-face consultations with residents and customized 

recommendations for specific actions that will reduce the residents' risk to lead exposure. The 

recommendations made to each resident are based on the results of envfronmental lead sampling 

at thefr homes and specific hiformation collected by the program about thefr daily habits and 

activities. Follow-up education, consultation, and intervention will contmue to be provided to 

families with young children by the Lake County Health Department through thefr blood-lead 

monitoring program. Women, Infants, and Children (WIC) program and Head Start. 

Residential property owners withm 0U9 may request an mvestigation oflead levels m soil, dust, 

pamt and water on the property. Property owners may request a re-mvestigation if condkions 

change. 

The LCCHP includes voluntary blood lead monitormg (with financial incentives, as appropriate) 

for all children age 6-72 months and voluntary blood lead monitoring for pregnant and nursmg 

women. 

Ifthe concentration oflead in blood of a child or for a pregnant or nursing woman exceeds the 

blood lead criterion, or ifthe concentration oflead exceeds a specified set of trigger criteria for 

29 
one or more ofthe envfronmental media at a residence, then appropriate actions will be taken to 

address the exceedance. The trigger criteria were selected by considering the mitial triggers used 

for the Kids Ffrst Program in addition to new infomation obtained through the baseline human 

health risk assessment. These trigger criteria are summarized below: 

Blood Lead greater than or equal to 10 micrograms/deciliter 

Soil greater than or equal to 3,500 parts per million 

Dust greater than or equal to 2,000 parts per miUion 

Pamt Interior or exterior paint, in poor condition, with the following lead levels 

greater than or equal to 1 milligram/centmieter" - Education 

greater than or equal to 6 milligram/centimeter^ - Active Remediation 

Tap Water greater than or equal to 15 micrograms/Uter 

When one or more ofthe trigger criteria are exceeded, a work group will evaluate a range of 

different response actions. The work group, to be established and managed by Lake County, will 

evaluate all envfronmental and blood lead data for a property and provide opinions on appropriate 

response actions. Membership ofthe work group will include representatives of Lake Coimty, the 

Colorado Department of Public Health and Envfronment, and ASARCO. The opinions ofthe 

work group, as approved by EPA, shall constitute the response action under CERCLA. 

The most appropriate response actions will be determined by evaluating the nature and extent of 

the exceedance, overall protectiveness ofthe action, compliance with apphcable or relevant and 

appropriate requfrements, long-term effectiveness and permanence, short-term effectiveness, 

implementability, cost effectiveness, and community impacts. The work group also will consider 

the views ofthe property ovraer. No response action wiU be taken without the permission ofthe 

property owner. An extensive education and uitervention program to manage lead exposure at the 

site will be an uitegral component of each action considered. 

The selected Remedy also mcludes the following mstitutional controls, to be developed during 

design ofthe remedy, to ensure effectiveness ofthe LCCHP. ASARCO and Lake County will be 

responsible for implementing and maintaming these institutional controls. 

1. The creation ofan overlay district to provide notification and information 

regarding the LCCHP, including requfrements that specify excavation activities or 

other uses would resuh m referral ofthe property owner to the LCCHP. 

30 
2. A data management and fracking system such as a computer database, to maintam 

sampling, response action and other hiformation related to mdividual lots or 

properties within OU9. This infomiation would be available to interested parties 

subject to notification through the overlay district. The data management system 

wm be accessible by all parties ofthe LCCHP work group. 

Since the LCCHP is a "pilot project" that involves a number of innovative approaches, it includes 

ongouig review to ensure that the program is operating as intended and that human health is beuig 

adequately protected. The review shaU uiclude: 

S Evaluation of participation of area residents in the blood lead monitoring and 

envfronmental media sampling programs. 

S Special effort to ensure collection of pafred blood lead and environmental lead data 

whenever possible. 

S Creation and application of a weU-documented quality assurance plan to ensure 

that blood lead and envfronmental data are collected and analyzed in the proper 

manner, and that the data are accurately entered into an ongoing database suitable 

for scientific evaluation. 

S Annualreportuigof summary statistics. 

Given that hazardous substances will remam onsite under the selected remedy, EPA also wiU 

conduct a five-year review pursuant to Section 121 ofCERCLA to ensure that the remedy is 

protective of human health and the envfronment. 

In addition, the remedy will be evaluated by a group of outside scientists. Details on how this 

group will be selected, operate, and evaluate the program will be mcluded m the work plan for the 

Lake County Community Heahh Program. 

EPA shall establish performance standards to define the process and criteria by which the remedy 

will be terminated. The perfomiance standards wiU be identified m an addendum to the remedial 

design. The CDPHE will be provided an opportunity for consultation and concurrence hi 

accordance with the National Contmgency Plan. ASARCO and local officials wiU also be 

consulted ui the development ofthe performance standards. 

The following sections discuss response actions associated with each ofthe trigger criteria. 

Response actions would be evaluated on a case-by-case basis by the work group and may be 

combined to form the most effective remedial solution. 

31 
Blood Lead 

The blood lead trigger level is independent of trigger criteria for soil, dust, paint, and water. In the 

event that a child or pregnant or nursmg woman has a blood lead level greater than or equal to 

10* g/dL, appropriate response actions will be taken, regardless of whether media trigger criteria 

have been exceeded, to reduce that exposure. The LCCHP wiU provide for continued monitoring 

of children with elevated blood lead concentrations beyond the age of six, ahhough those children 

would be beyond the age group at highest risk from exposure to lead. The response actions to be 

considered for identified potential sources oflead exposure, resulting in blood lead concentrations 

greater than or equal tolO* g/dl, shaU mclude any ofthe actions described below for soils, dust, 

pauit, and water. In addition, other potential lead sources beyond an uidividual residence, and 

within 0U9, may be considered by the LCCHP work group for remediation and/or education to 

address exposure. 

Residential Soils 

The trigger criterion for residential soil remediation under the LCCHP is: soil-lead concentration 

greater than or equal to 3,500 ppm. The followmg response actions could be taken for residential 

soils. 

• No Action: This response may be implemented if soil-lead concentrations are less 

than 3,500ppm. 

• Contauiment: This option uicludes the following mstallation ahematives to contaui 

soils. AUeraatives Usted here may be used in combination on any given property. 

For example, sod placement could replace existmg yard and a concrete cap may be 

used to replace a dirt driveway. 

Soil cap: Borrow soil placed over impacted areas. 

In situ mixing: Mixing of surficial soils havuig lead concentration above 

3,500 ppm with imderlying unimpacted soils could be performed to reduce 

lead concentrations to acceptable levels. Homes with soil-lead 

concenfrations greater than 3,500 ppm m the 6-12 inch depth mterval are 

not considered amenable to this altemative due to the difficulty m mixmg to 

the depths required to achieve the objective. 

Sod placement: Sod placed over impacted soils. 

Compacted clay cap: Compacted clay placed over impacted areas with a 

minimum one-foot silty or sandy protective layer to maintain cap integrity. 

32 
Sprayed asphalt: Sprayed asphalt placed over impacted areas and covered 

with soil or opaque reflective paint to protect the asphalt from ultraviolet 

light and retard oxidation. 

Asphahic concrete: Asphalt for pavmg grades or special blends mixed with 

weU graded, crushed aggregate, placed over impacted areas. 

Concrete cap: Concrete placed over prepared impacted areas. 

Multilayered cap: Cap composed of some combination of natural soils, soil 

admixtures, clay, spray-on asphalt, asphaltic concrete, or Portland cement 

and placed over impacted areas. 

• Diversion ditch constmction: Constmction of diversions and/or culverts may 

prevent run-on to source areas and reduce both erosional and leachmg release of 

the metals from a source. 

• Removal: Removal of soil would be accomplished through hand excavation with 

the aid of mechanical excavation equipment. The removal depth would be decided 

on a case-by-case basis based on site-specific infomiation, but would be no more 

than 12 inches. During excavation and fransport, dust suppression may be 

necessary. After excavation, borrow material would be transported to the 

residence and placed. Yards would be revegetated, generally with sod. In instances 

where remaining soils may exceed the trigger criterion, such soils would be subject 

to institutional controls. 

Excavated material could be put to beneficial re-use as non-surficial fill material or 

could be removed to a suitable on-site repository. 

In-Residence Dust 

Potential sources of lead for in-residence dust are: lead-based pauit hi poor condition, bare soil 

areas, gardens, streets and alleys, tailings, and mine waste. Dust is transported into the home by 

wind or on hems taken outside and then retumed inside. The frigger level for in-residence dust is 

lead concentrations greater than or equal to 2,000 ppm. Response actions would be: 

• No Action: Residences with dust-lead levels between 500 and 2,000 ppm will be 

mformed about lead dust abatement methods and offered use of a High Efficiency 

Particulate Afr (HEPA) vacuum. 

• Physical Protective Measures: This response action mclude sealmg off unfinished 

basements, attics, or crawl space areas to Ifrnit exposure to ulterior lead-dust. 

33 
• Education Program: This response may be enacted to educate residents on how to 

effectively reduce lead-dust when cleaning. Demonstrations or brochures may be 

used. 

• Removal and Disposal bv Means of Decontamination or Replacement: One or a 

combination ofthe following methods may be considered for removing ulterior 

leaddust: Vacuum all mterior livmg spaces with a HEPA vacuum. Dust can be 

disposed of m a RCRA Subtitle D landfill as it is household waste. Damp mop all 

floors, wuidow weUs, and other wood work with a trisodium phosphate (TSP) 

cleaning solution; clean fiiraace ducts using the EPA-approved program for duct 

cleaning; and placement of mats at entryways so that shoes may be appropriately 

shaken or wiped before entering, reducing the amoimt of soil entering the 

residence. 

Interior and Exterior Paint 

Residences may have interior and/or exterior pauit that is lead-based. Lead-based pamt ui poor 

condition may contribute to lead exposure through mhalation and ingestion of dust, or dfrect 

consumption of paint chips. Depending on the paint's lead concenfration and condition the 

foUowing response actions may be considered: 

• No Action: This response action will be implemented if lead levels are less than 1 

mg/cm" or if no lead-based pauit is identified. 

• Education. Contamment. Covering, or Removal: If paint contains lead above 1 

mg/cm" and is ui poor condition (peeling, chipping, chalking) or coating a 

fliction-surface, education, risk coimselmg, and information on actions they may 

take themselves will be provided to residents. If pauit has lead levels greater than 

or equal to 6 mg/cm^, and is in poor condition, active remediation would be 

recommended. If either encapsulation or removal is chosen for remediation, the 

remediated areas will have a surface paint-lead level no greater than 1 mg/cnf. 

• Community Protective Measures: HUD disclosure requfrements for lead-based 

pamt will be relied upon to notify potential fiiture buyers ofany potential 

lead-related risks. 

Drinkuig Water 

Residences may have drinking water that contauis lead. Lead m drinking water may be associated 

with lead solder, lead plumbing, or lead alloy fixtures. The action level for lead in drinking water 

is lead concentrations greater than or equal to 15 • g/L. Lead concentrations in drinking water can 

be measured and the following response actions may be considered: 

34 
• No Action: This response action could be implemented ifthe lead concentration m 

drinking water is less than 15 • g/l. 

• Altemative Water Supplv: This response action could provide the replacement of 

unsuitable drinking water with bottled water, municipal water, or a household 

water treatment system could be instaUed. 

• Replacement: The removal and replacement response could be appropriate for 

residences with lead m drinkmg water from lead piping or soldering. 

XI. STATUTORY DETERMINATIONS 

Under CERCLA Section 121, EPA must select a remedy that is protective of human health and 

the envfronment; that complies with ARARs; is cost effective; and utilizes pennanent solutions, 

and altemative treatment technologies, or resource recovety technologies to the maxunum extent 

practicable. In addition, CERCLA mcludes a preference for remedies that mclude treatment which 

permanently and significantly reduces the volume, toxicity, or mobility ofhazardous wastes as a 

principal element. The Selected Remedy does not satisfy the statutory preference for treatment as 

a principal element ofthe remedy. The following sections discuss how the Selected Remedy meets 

statutory requfrements. 

Protection of Human Health and the Environment- The selected remedy is 

protective of human health and the envfronment by addressing addhional sources oflead in 

conjunction with soil remediation (if requfred). Treatment is not practical and therefore is 

not used. 

Compliance with ARARs- The selected remedy will comply with all ARARs identified 

m Appendix C to this ROD. No waiver of ARARs is expected to be necessaty. 

Cost Effectiveness - EPA has detennined that the Selected Remedy is cost effective in 

mitigating the principal risks posed by contaminated residential soils. Section 300.430 

(f)(ii)(D) ofthe NCP requfres evaluation of cost effectiveness. OveraU effectiveness is 

determined by the following three balancmg criteria: long-term effectiveness and 

permanence; reduction of toxicity, mobility, and volume through treatment; and short-term 

effectiveness. Overall effectiveness is then compared to cost to ensure that the remedy is 

cost effective. The Selected Remedy meets the criteria and provides for overall 

effectiveness in proportion to its cost. The estimated cost for the Selected Remedy is 

$4.84 milUon. 

To the extent that the estunated cost ofthe Selected Remedy exceeds the cost for other 

alteraatives, the difference in cost is reasonable when related to the greater overall 

effectiveness achieved by the Selected Remedy. 

35 
Utilization of Permanent Solutions and Satisfies the Preference for Treatment that 

Reduces Toxicity, Mobility, or Volume- The selected remedy utilizes pemianent 

solutions to the maximum extent practicable but does not satisfy the preference for 

alteraatives that involve treatment to reduce the toxicity, mobility, or volume of 

contamination. 

Long Term Effectiveness and Permanence- Risk to residents would be reduced due to 

selection ofthis remedial action for the reduction of total lead exposures. This remedy 

would resuh m waste being left in place. 

Reduction of Toxicity, Mobility or Volume through Treatment- The selected 

altemative does not involve treatment; however, the total lead exposure for a given 

residential living envfromnent will be reduced. 

Short-Term Effectiveness- Short-term risks to workers and residents are acceptable. 

Implementability- Inplementation ofthe selected remedy is expected to be successful 

based on the support of Lake County officials and the CDPHE, as well as elected 

representatives from both the City of LeadviUe and Lake Coimty. Community support for 

the Kids Ffrst Program also indicates that implementation ofthe selected remedy will be 

successfiil. This altemative utilizes common constmction, home improvement, cleanmg 

equipment, and procedures defmed in HUD guidance. This altemative allows for flexibility 

m selecting the most appropriate response actions on a case-by-case basis, while 

considering resident needs and preferences. 

Cost - The estimated cost for the LCCHP is $4,839,250. The cost for this ahemative is 

mid-range with respect to other altematives. 

XII. DOCUMENTATION OF SIGNIFICANT CHANGES 

EPA distributed a Proposed Plan outlining the prefened alteraatives ui November 1998. The 

Proposed Plan identified Altemative 7, the LCCHP, as the prefened altemative for the Residential 

Populated Areas Operable Unit. No significant changes have been made to the Alteraative 7 

decision described in the Proposed Plan. Public comment generally supported implementation of 

the LCCHP. PubUc comments and EPA's responses to those comments are attached as Appendix 

A. 

The remedy will be continually monitored for effectiveness. Any problems with the program will 

be identified and adjusted as necessaty. 

36 
XIII. REFERENCES 

References: 

1907. The Downtown District of Leadville, Colorado, Samuel Franklin Emmons and John Duer 

Irving, Govemment Printing Office, Washmgton, D.C. 

1927. Geology and Ore Deposits ofthe Leadville Mining District, U.S.G.S., S. F. Emmons and J. 

D. Irving. 

1987. Cahfomia Gulch Remedial Investigation, LeadvUle, Colorado, CH2M Hill, May. 

1990. U.S. Bureau of Census 

1992. Soil Inventoty and Map, Califomia Gulch Study Area, Leadville, Colorado, Walsh and 

Associates, May. 

1993. Final Smelter Remedial Investigation Report, Califomia Gulch Site, Leadville, Colorado, 

Walsh and Associates, April. 

1994. Fmal Soils Investigation Data Report, Caffomia Gulch CERCLA Site, LeadviUe, Colorado, 

Volume 1, Text, Camp, Dresser and McKee, Inc. July. 

1994, Consent Decree between the United States, State of Colorado, ASARCO and Resunection, 

Lodged m U.S. District Court m Denver, May 17, 1994. 

ASARCO, 1994. Work Management Plan for ASARCO fric. at the Califomia Gulch NPL Site, 

Leadville CO. Prepared by Woodward Clyde. Appendix B to the Consent Decree. 

ASARCO, Incorporated, 1994. Engineering Evaluation/Cost Analysis for Parks and Playground 

Areas, Operable Umt 9, Califomia Gulch, LeadviUe, Colorado. Prepared by Woodward Clyde 

Consultants, November. 

ASARCO, Incorporated, 1995. Engmeering Evaluation/Cost Analysis for Muie Waste Piles, 

Operable Unh 9, CaUfomia Gulch Superfimd Site, Leadville, Colorado. Prepared by Golder 

Associates. December. 

Envfronmental Protection Agency (EPA). 1993. Fmal Screening Feasibility Study for Remediation 

Altematives at the Califomia Gulch NPL Site, Leadville, Colorado. September. 

37 
Envfronmental Protection Agency (EPA). 1996a. Baseline Human Health Risk Assessment 

Califomia Gulch Superfund Site, Leadville, Colorado, Part A ~ Risks to Residents from Lead, p. 

8-6. Prepared by Roy F. Weston, Inc. Januaty 1996. 

Envfronmental Protection Agency (EPA). 1996b. Baseline Human Heahh Risk Assessment 

Cahfomia Gulch Superfund Site, Leadville, Colorado, Part B ~ Risks to Residents from 

Contammants Other than Lead. Prepared by Roy F. Weston, Inc. Januaty 1996. 

Envfronmental Protection Agency (EPA). 1996c. Baseline Human Health Risk Assessment 

Califomia Gulch Superfimd Site, Leadville, Colorado, Part C ~ Evaluation of Worker and 

Recreational User Scenarios. Prepared by Roy F. Weston, Inc. Januaty 1996 

Envfronmental Protection Agency (EPA). 1996d. Interim Status Report, Consolidated Findmgs of 

Soil-Lead Investigations at the Califomia Gulch NPL Site. Prepared by Roy F. Weston, Inc. June. 

Woodward Clyde Consultants, 1994. Final Work Plan for Kids Ffrst Program, Califomia Gulch 

NPL Site, Leadville, Colorado. Prepared for ASARCO, Incorporated, Denver, Colorado. 

Golder Associates, 1998. Final Residential Soils FeasibUity Study, Califomia Gulch Superfund 

Site, Leadville, Colorado. Prepared for ASARCO, Incorporated, Denver, Colorado. 

38 
Appendix A 

SITE LOCATION MAP 
1 f 
Appendix B 

RESPONSIVENESS SUMMARY 
Responsiveness Summary 

In November 1998, the Envfronmental Protection Agency issued a Proposed Plan describing the 

Agency's prefened aheraative to address risks to residents from lead in soils and other sources within 

Operable Unk 9 ofthe Califomia Gulch Superfand Site m Leadville, Colorado. A public meetuig to 

discuss the Proposed Plan was held in Leadville on November 19, 1998. Public comment on the Proposed 

Plan was accepted from November 12, 1998 through December 14, 1998. 

The purpose ofthis Responsiveness Summaty is to provide aU comments received on the 

Feasibility Study, Proposed Plan, or during the public meetmg and provide the Agency's response to 

those comments. AU comments are included in the Adminisfrative Record for this project. 

FEASIBILITY STUDY 

Following are comments from the Colorado Department of Public Health and Envfronment (CDPHE) on 

the FeasibiUty Study. Each CDPHE comment is followed by EPA's response. 

CDPHE Comment 1 

The text for Altemative 7 should be revised to more accurately reflect the cunent Kids Ffrst Program's 

practice of accommodating the homeowner's preferences as part ofthe Kids First Work Group 

deliberative process of remedy selection. Typically, the deliberative remedy selection process associated 

with Altemative 7 should be m accordance with the property owner's preference. In addition, the 

property owner should fully understand any institutional controls that would be associated with leaving 

wastes on his/her property. 

Response 1 

Altemative 7 is based on the Kids Ffrst Program and has been designed to fully consider the views ofthe 

property owner. No response action will be conducted without the pennission ofthe property owner. An 

extensive education and intervention program to manage lead exposure at the site will be an mtegral 

component of each action considered. 

CDPHE Comment 2 

Section 3.4.3.5 ofthe FS mentions various mstitutional controls such as land use controls, deed 

restrictions, permitting, etc., that could be used as a separate remedial ahemative or as a component of 

various other remedial ahematives. However, the FS fails to present an m-depth discussion ofthis issue. 

A more detailed discussion of all the potential mstitutional controls is needed, especiaUy a discussion of 

how they would apply to remedial Ahemative 7 (see previous comment). Such specifics as: which 

institutional controls will be employed for the various 
altematives, how they will be employed, and by whom they will be employed should be fliUy discussed. In 

order for the FS to adequately evaluate effectiveness, UnplementabiUty and cost, this cmcial issue should 

not be defened until the design phase ofthe remedial process. (Also see: CDPHE General Comment #2 

in conespondence to EPA dated May 28, 1996, on the Draft residential Soils FS and General Comment 

#7 in correspondence dated Januaty 8, 1997, on the Redraft of Altemative 7a and 7b.) Also, please refer 

to EPA's Draft Reference Manual on Institutional Confrols, March 1998, for early uitegration of 

institutional confrol considerations. 

Response 2 

Alteraative 7, the Selected Remedy, mcludes the following mstitutional controls, to be developed during 

design ofthe remedy, to ensure effectiveness ofthe Lake Coimty Commimity Health Program (LCCHP). 

ASARCO and Lake County wiU be responsible for implementmg and mamtainmg these institutional 

controls. 

1. The creation of an overlay district to provide notification and information regarding the 

LCCHP, uicludmg requfrements that specify excavation activities or other uses would 

result Ul refenal ofthe property owner to the LCCHP. 

2. A data management and fracking system such as a computer database, to maintam 

sampling, response action and other infomiation related to individual lots ro properties 

within OU9. This mformation would be available to uiterested parties subject to 

notification through the overlay district. The data management system will be accessible 

by all parties ofthe LCCHP work group. 

CDPHE Comment 3 

An on-site repositoty for the disposal of residential soils is mentioned, however, there is no discussion of 

where the repositoty will be located. The specific location, including size and a discussion of sking 

criteria, should be uicluded. Accordmgly, State Solid Waste Regulations pertauimg to SoUd Waste 

Disposal Site and Facilities (6CCR 1007-2) Sections 2 & 3 should be included as a potentially relevant 

and appropriate ARAR. 

Response 3 

Any excavated soils will be removed to a sukable on-site repositoty. The specific location and size ofan 

on-site repositoty wiU be addressed during remedial design. Please refer to Appendix C to the Record of 

Decision for a complete hsting of aU applicable or relevant and appropriate requfrements. Specific State 

Solid Waste Regulations are identified as ARARs. 

CDPHE Comment 4 

The CDPHE, APCD, Regulation 19 is currently being evaluated as potentiaUy appUcable or relevant and 

appropriate (ARAR) for lead-based pamt abatement (i.e., remediations). The CDPHE, as you know, is 

currently actively workmg with E PA Region VIII lead-based pamt 
program representatives to detennine which elements ofthis regulation may affect remedial activities in 

OU9. Any issues in this context will be resolved as soon as possible. 

Response 4 

Comment noted. The agreed upon provisions from Regulation 19 have been mcluded in the ARARs table. 

Appendix C. 

CDPHE Comment 5 

In their Comment 5, CDPHE identified a number of ARARs for uiclusion ui the summation of ARARs 

for Operable Unit 9. 

Response 5 

Please see Appendix C to the Record ofDecision for a complete listmg of all appUcable or relevant and 

appropriate requfrements. CDPHE has conciured wkh the compilation of ARARs. 

PROPOSED PLAN 

FoUowuig are comments from CDPHE on the Proposed Plan. Each CDPHE comment is followed by 

EPA's response: 

CDPHE Comment 1 

CDPHE's support that the ROD be revised to conform with CDPHE's understanding ofthe Kids Ffrst 

Program's practice of accommodating the homeowner's preferences and concems in the Kids First 

Workgroup's deliberative process of remedy selection. 

Response 1 

Please see EPA's response to CDPHE's Comment 1 on the Feasibility Study. 

CDPHE Comment 2 

To the extent possible, and in conformance with EPA Institutional Control (IC) guidance, likely ICs 

associated with the selected remedy should be identified and discussed m the ROD. This would facilitate 

a better understanding by the parties (and participatuig property owners) ofany duties, obligations, or 

potential UabiUties that may be associated with the implementation ofthe selected remedy. 

Response 2 

Please see EPA's response to CDPHE's Comment 2 on the Feasibility Study. 
FoUowuig are comments from ASARCO on the Proposed Plan. Each ASARCO comment is followed by 

EPA's response. 

ASARCO General Comment 1 

Throughout the Proposed Plan it states that all sources oflead will be addressed. Generally, Asarco 

supports addressing all sources oflead, but as we have discovered through the unplementation ofthe 

Kids Ffrst Program this is impractical, if not impossible. The LCCHP will address primaty sources oflead 

exposure to children (i.e., soil, dust, paint, and water) and attempt to identify other potential pathways of 

lead exposure. 

Response 1 

EPA recognizes soil as the primaty pathway of exposure to the residential population at the site. Dust, 

pamt and water are other pathways of exposure. Other potential lead sources beyond an uidividual 

residence, and withui 0U9, may be considered by the LCCHP work group for remediation and/or 

education to address exposure. 

ASARCO General Comment 2 

As there has been some concem raised regarding the accuracy ofthe Superfund Site and Operable Unit 

boundaries on the map attached to the Proposed Plan, ASARCO supports using the Operable Unk 

boundaty map included m the Consent Decree, Appendix C, Attachment 1 (also presented as Figure 2-1 

m the Feasibility Study). 

Response 2 

The map included as Appendix C to the Consent Decree will be used to identify Operable Unk and Site 

boundaries for the Record ofDecision. 

ASARCO Specific Comment 1 

The proposed plan states, "The second approach compared the measured blood lead values in area 

children with relevant national blood lead statistics m order to help evaluate the cunent impacts of actual 

site exposures to lead." 

The comparison to national blood lead statistics was a minor part ofthe way m which EPA used the 

measured blood lead levels hi the risk assessment. It would be more accurate to emphasize that the blood 

lead levels were analyzed along with conesponding envfronmental data for soil, dust, water, paint and 

other factors to help evaluate the cunent impacts of actual site exposures to lead. 

Response 1 

Comment noted. 
ASARCO Specific Comment 2 

The proposed plan states, "In 1991, geometric mean blood lead levels m children living withui the site 

boimdaries were typically around 5-6 • g/dl..." 

The geometric mean blood lead level is a single value for a specific group, not a "typical" value m a 

range. The geometric mean blood lead level for the 284 children age 0-72 months who were Uving within 

the ske in 1991 was 4.7 • g/dl, as reported on page 5-3 ofthe Baseline Human Health Risk Assessment 

(BHHRA), Part A. The range of 5-6 • g/dl does not conespond with the values reported for subareas 

from the University of Cmcinnati study used in the BHHRA. Geometric mean blood lead levels withui the 

subareas designated A-G ranged from 3.9 to 6. 6 • g/dl; geometric mean blood lead levels for the two 

subareas within Lake County but outside ofthe Superfund Site boimdaries were 3.1 and 6.0 • g/dl. 

Response 2 

Comment noted. 

ASARCO Specific Comment 3 

Item 2 states in part that "Additional blood lead data collected by [the] county health agency from more 

than 100 children per year for each year between 1991 and the present suggests that the mcidence of 

children in the community with blood lead levels above 10 • g/dl is contmumg to fluctuate between 6% 

and 9%." This statement appears to overstate the cunent commimity blood lead levels observed m 

Leadville. Using the guidelines for data reduction estabUshed m the memo to EPA from Dr. Bill Brattin, 

EPA's toxicology consultant (December, 1997), we fmd that in 1997 5.8% (14 children) of all 240 

children tested and living within the site had blood lead levels over 10* g/dl. 

Response 3 

Comment noted. 

ASARCO Specific Comment 4 

In the proposed plan it states, "It was concluded that soil and dust ingestion rates m this community were 

probably somewhat lower than national average rates possibly because the ground is frozen or snow 

covered approxunately eight months out ofthe year. " 

While ASARCO agrees with this conclusion, we would like to clarify that national average rates for soil 

and dust ingestion are not known and that the precise amount of soil uigested anywhere is not well 

understood. The assumptions used m the lEUBK model reflect results from a vety limited number of soil 

ingestion studies along with modifications to estimated soil ingestion rates by age group so that the 

predicted blood lead levels appear to match the observed values. No soil ingestion studies specifically 

support the age-specific soil ingestion rates used m the lEUBK model. Other possible reasons why the 

LEUBK model predictions and the blood lead observations did not match is that the model may fail to 

accurately predict tme "backgroimd" blood lead levels due to non-soil sources, which may lead to a 

failure to accurately predict blood lead uicreases due to soil exposure; and the model may overestunate 

the importance of soil lead exposure fri predicting blood lead levels. 
Response 4 

Comment noted. 

ASARCO Specific Comment 5 

With respect to the proposed trigger criteria for mterior and exterior paint with lead concentrations above 

1 mg/cm^ and in poor condition, Asarco would like to reiterate its desfre to implement a tiered approach 

where: 1) pamt remediation abatement is performed if lead pamt concentrations are found to be greater 

than 6 mg/cm^ and paint is in poor condition; 2) education, and property owner requfrements (based on 

applicable federal laws), would be the measures taken for homes where lead pamt concentrations are 

found to be below 6 mg/cm^ and above 1 mg/cm^, or where lead paint concenfrations are above mg/cm^ 

and paint is hi good condition; and 3) no action is taken if lead paint concentrations are 1 mg/cm^ or 

lower. Education will be performed on issues such as: encapsulation, avoidance, care and mauitenance of 

pakited surfaces, and precautions to be taken during future remodeling projects by homeowner. 

Asarco believes that the 6 mg/cm^ and poor condition action criteria currently beuig used under the Kids 

Ffrst Program for remediation of paint is protective of human health and the envfronment, and upholds 

the original mtent ofthe Consent Decree. As mdicated in the Work Area Management Plan (WAMP), the 

concept of community-based lead reduction program such as the LCCHP was developed as an alteraative 

to wholesale soil removal to address sources oflead exposure to young children besides soil. Asarco 

voluntarily agreed to remediate homes that pose significant lead paint risks (i.e., 6 mg/cm^ or greater and 

pamt m poor condition) as part ofthe overall lead risk reduction program, even though lead paint 

abatement is not a CERCLA action. The voluntaty nature ofthe agreement to uiclude lead pamt in a 

community program attests to Asarco's support for reduction oflead risks m young children. 

Response 5 

The selected remedy includes a tiered approach to lead-based paint remediation. If lead levels are less 

than 1 mg/cm^, no action will be taken. If paint contains greater than or equal to 1 mg/cm" and is m poor 

condition (peeling, chippmg, chaUcing) or coating a fiiction-surface, education, risk counseling, and 

frtformation on actions they may take themselves will be provided to residents. If paint has lead levels 

greater than or equal to 6 mg/cm ^, and is m poor condition, active remediation would be recommended. If 

either encapsulation or removal is chosen for remediation, the remediated areas will have a surface 

paint-lead level no greater than 1 mg/cm^. 

ASARCO Specific Comment 6 

Asarco feels that "and accessible" should be added to the trigger criteria for soil. The LCCHP is a risk 

based program, thus, Asarco feels that the condition of soils or more specifically the accessibility to soil is 

an important part ofthe trigger criteria for soil. The exposure pathway for soils is greatest when poor 

vegetative conditions exist such as a bare area in the yard or a garden area where bare soils can be 

exposed for part ofthe year. If there is a good year round vegetative cover the pathway is blocked. The 

LCCHP Work Group should have the opportunity to recommend, and residents should have the 

opportunity to select, education and 
possibly some type of voluntaty mstitutional controls and not destroy an existmg vegetative cover. Also 

for open areas, the Work Group could recommend vegetative enhancement without destroymg the native 

vegetation that exists. 

Response 6 

The selected remedy offers a wide range of options to address potential exposure from soils greater than 

or equal to the trigger criteria for soil. Containment is one ofthe options and could rely upon vegetation 

as a banier to any exposure. 

ASARCO Specific Comment 7 

The following reference is missing as refened to on page 4 for (U.S. District Court, 1994). 

"hi the United States District Court for the District of Colorado (U.S. District Court). 1994. Consent 

Decree with ASARCO, Incorporated, Resunection Minmg Company, Newmont Minuig 

Corporation, and the Res-ASARCO Jomt Venture. August 25." 

Response 7 

Reference to the Consent Decree is made in the Record ofDecision selecting the remedy for Operable 

Unit 9 ofthe Califomia Gulch Superfund project. 

EPA received a number of comments from the general pubhc during the public comment period. 

Following are comments from the general public on the Proposed Plan. The complete text of each public 

comment is available in the Administrative Record. Each comment is followed by EPA's response. In 

addition to the comments presented below, EPA received 21 post cards from community residents in 

support of Aheraative 7, the Lake County Community Health Program. No post cards were received m 

opposkion to the prefened altemative. 

Comment 1 

As long as actual blood lead levels are used as the inkial trigger for further action, I strongly support this 

proposal. 

Response 1 

Blood lead levels in children are not the only trigger for remedial actions. Residents may elect to 

participate hi the environmental testmg and remediation program without blood lead testmg or to 

participate without releasing information on thefr blood lead levels. 

Demonstration of attainment ofthe perfomiance standards for 0U9 will, however, be based on actual 

blood lead levels m children residing in LeadviUe. The overaU effectiveness ofthe LCCHP will be 

demonstrated through attauiment of perfomiance standards. 
Comment 2 

Institutional controls should, for the most part, be uicluded as part ofthe Record ofDecision 

regardmg this matter to assure that Lake County and other entities are not burdened with mappropriate 

long range liabilities. These confrols should be developed with the input of all uiterested parties to assure 

that they are reasonable and science based. 

Response 2 

Institutional controls are discussed further in the Record ofDecision (ROD) and will be fmalized during 

the design phase ofthe program with local commimity mvolvement. EPA and ASARCO are prepared to 

work cooperatively with Lake County and the City of Leadville to develop institutional controls. 

Discussions regarding the manner in which the LCCHP wiU be implemented and additional actions, if any, 

required or desfred once perfonnance standards are met will be integral to the development ofan 

appropriate institutional controls program at this site. For this reason, institutional confrols will be 

developed as part ofthe remedial design and presented m detail withm the Work Plan for the LCCHP. 

Comment 3 

The City of Leadville should also be mcluded as an entity to be consuhed m the review and approval 

process (re: changes or variances to Standard Operatuig Procedures included in the LCCHP work plan). 

Response 3 

We agree that the City of Leadville should be involved wkh any changes made to the Standard Operatmg 

Procedures for the LCCHP. 

Comment 4 

Institutional controls which mclude zoning changes or deed restrictions may have little community 

support. In addkion, use oflead concentration contour maps to delmeate areas where mstitutional 

controls would be unplemented is likely to be disputed by home owners. 

Response 4 

EPA and Asarco are prepared to work dfrectiy with Lake County and the City of Leadville to identify 

institutional controls that will be both effective and unplementable. Several diverse groups, which include 

members from the Leadville community, cunently provide opportunkies for ckizens to take an active role 

m the consultation and decision-makmg process for the site. These groups mclude the Site Activities 

Coordinatuig Committee and Kids Ffrst Work Group. 

EPA does not mtend to identify areas for mstitutional controls based on concentration contour maps 

previously presented ui the Feasibility Study. Instead, appropriate mstitutional controls will lUcely be tied 

to the status of remediation at individual properties. For example, if 
envfronmental lead sources have been tested but none ofthe trigger levels was exceeded, then no 

institutional confrols would be requfred specific to that property (such as land use restriction or deed 

notice). 

Comment 5 

It might be reassuring to the community to extend blood lead monitoring beyond the children presently 

tested in the voluntaty program, so as to evaluate the potential effects of residential properties not 

presently housing children. 

Response 5 

The LCCHP will be open to all residents hi the site regardless of whether or not a child under 6 years old 

resides at the property. Envfronmental testing at properties both with and without children under 6 

insures the protection of children who may reside at a property m the future. 

Comment 6 

A sampling program involving the testing of domestic cats might provide a pioneering avenue of study ... 

This might be a far less expensive and more effective program than resuhed from the inconclusive effort 

mvolvmg swine testmg. 

Response 6 

Several lead researchers have suggestmg usmg cats or dogs as monitors oflead exposure. Unfortunately 

thefr use is still quite experimental, and unsuitable for our purposes. For example, Philip Bemy studied 

pets living in homes of children in Granke City, IL. While dogs and cats had blood lead levels more or 

less Ul the range of childrens' levels, there was no reliable conelation. If a pet had a blood lead level over 

10 • g/dl, then there was a chance that a child living m the house did, as well, but the association was not 

reliable enough to use the pet's measurement instead ofthe children's. Also, it is not really imderstood 

what lead exposure is reflected m a dog's or cat's blood lead level. Dogs kept tied outside are not exposed 

to house dust lUce children are, and cats kept uiside are not exposed to yard soil. Cats that go outside may 

roam away from the home and may not represent exposure at the home itself Finally, pets will not be 

exposed to dfrect sources oflead such as old toys or lead-based pamt on staircases or window ledges in 

the same way that children may be. In conclusion, we now feel that although pets may be somewhat 

useful m the future as a screenmg tool m conjunction with other environmental data, it will always be 

more effective to look at lead in the envfronment from the child's point of view. 

Although the ffrst swme-feeding test usmg Leadville soil was, inconclusive on its own, EPA has done 

many swine tests and other extraction tests suice then to study bioavailability of lead from many different 

sites, including recent tests using soils from other skes m Leadville. EPA is hopeful that the new test 

results for Leadville will help explain some ofthe unusual (higher or lower) blood lead resuhs in different 

neighborhoods of Leadville and will contribute to our understanding ofthe bioavailability oflead ui soils 

from residential areas of Leadville. 
Comment 7 

I believe that people are being bribed into testmg blood lead levels [with savmgs bonds and gift 

certificates]. Is this typical nationwide? 

Response 7 

There are other communities m the United States, both CERCLA and non-CERCLA skes, that offer 

incentives to encourage participation in blood lead testmg programs and to increase the accuracy and 

effectiveness of those monitoring programs. The mcentives currently used hi LeadviUe appear to have 

been effective in maintaining a high level of community participation in the county's blood lead 

monkoring program. It is unportant to note that the blood lead program is voluntaty under the CERCLA 

action. Blood lead testing is not and wiU not be a requfrement for envfronmental lead testing or, if 

necessaty, remediation. 

Comment 8 

I wish I could believe that all ofthis site work is needed and that it does pose an imminent and substantial 

endangerment to public heahh and welfare. I prefer Altemative 1: No Action as the prefened altemative 

for the residential area. 

Response 8 

EPA agrees that the risk to the ckizens of Leadville is moderate as demonstrated by the on-going blood 

lead program bemg conducted by Lake County. EPA prefers the LCCHP, because it will cause the least 

amoimt of disturbance to the community while being protective to cunent and future residents at the site. 

In addition to written comments received during the public comment period, EPA also received some 

verbal coinments during the public meetuig conducted on November 18, 1998. FoUowing are each ofthe 

comments made during the public meetuig followed by EPA's response. 

Comment 1 

Are there areas m the Site where children's blood lead levels are higher? Do you see any clustering of 

children with elevated blood lead levels? 

Response 1 

Areas ofthe Site where children are more likely to have an elevated blood lead concentration uiclude the 

east side of Leadville near the historic minmg district, Stringtown, and the Lake Fork trailer park near the 

confluence of California Gulch and the Arkansas River. 
Comment 2 

What are the community protective measures, how are they being developed, and is the local community 

gouig to have mput on the community protective measures? 

Response 2 

Ahemative 7, the Selected Remedy, includes the following histitutional confrols, to be developed during 

design ofthe remedy, to ensure effectiveness ofthe Lake County Community Health Program (LCCHP). 

ASARCO and Lake County will be responsible for implementmg and mamtaining these mstimtional 

controls. 

1. The creation ofan overlay district to provide notification and mformation regarding the 

LCCHP, including requfrements that specify excavation activities or other uses would 

result in refenal ofthe property owner to the LCCHP. 

2. A data management and tracking system such as a computer database, to maintain 

sampling, response action and other information related to uidividual lots ro properties 

within 0U9. This mformation would be available to uiterested parties subject to 

notification through the overlay district. The data management system will be accessible 

by aU parties of the LCCHP work group. 

Comment 3 

The County is opposed to usmg the 0-6 inch lead m soils distribution map as shown m the Feasibility 

Study (Figure 2-2). This map was developed using samples from streets and alley ways instead of actual 

yards. 

Response 3 

Any soil response actions will be based on property-specific data, not the lead in soils distribution map 

presented m the FeasibiUty Study. 

Comment 4 

How will histitutional confrols be unplemented as a voluntaty program? 

Response 4 

EPA and ASARCO are prepared to work dfrectiy with Lake County and the City of Leadville to identify 

institutional controls that will be both effective and implementable. Several diverse groups, which mclude 

members from the Leadville community, cunently provide opportunities for ckizens to take an active role 

Ul the consultation and decision-making process for the site. These groups include the Ske Activities 

Coordinatuig Committee and Kids First Work Group. Appropriate institutional controls will likely be tied 

to the status of remediation at mdividual properties. 
Comment 5 

The Coimty is opposed to mstitutional controls. Why are they Usted in the feasibility study? 

Response 5 

Institutional controls are listed in the Feasibility Study to mvestigate these options further. EPA 

understands that the County supports implementation of institutional confrols as described in the ROD. 

Comment 6 

How may properties will need soil remediation? 

Response 6 

The estimate is 150 homes. 

Comment 7 

I am opposed to sweeping zonuig restrictions. How will vacant lots and new development be addressed? 

Response 7 

The selected remedy will not mfluence zoning. In the event that development disturbs contaniinated soils, 

appropriate measures to manage the soils would have to be taken. Appropriate measures would depend 

on eventual land use. 

Comment 8 

How were trigger levels established? 

Response 8 

Risk assessments were relied upon to establish trigger levels. 

Comment 9 

In the feasibihty study k says that the program will last for 12 years. After that time, does the County 

have to bare the cost? 

Response 9 

ASARCO is responsible for implementing the LCCHP untU perfonnance standards have been met. 
Comment 10 

Once the blood lead levels goals are met, how many years does the program have to contmue? 

Response 10 

The Program will continue until performance standards have been met. EPA will conduct five year 

reviews ofthe Site to ensure that the remedy remains protective. 

Comment 11 

What happens 10 years down the road when the program loses momentum, how will the remediation be 

ensured? 

Response 11 

Incentives will be offered to ensure adequate participation in the program. EPA will conduct five year 

reviews to ensure that the remedy remains protective. 

Comment 12 

Could the Site be delisted even if all properties do not have sampling/remediation conducted? 

Response 12 

Once performance standards have been met, EPA will proceed with deUstmg. 

Comment 13 

How long until the LCCHP can be implemented? 

Response 13 

We anticipate that the program will begin in 1999. 

Comment 14 

If a property owner refuses to participate, will fences be put around the property? 

Response 14 

No. 
Appendix C 

APPLICABLE OR 

RELEVANT & APPROPRIATE 

REQUIREIMENTS 
SUMMARY OF POTENTUL ARARS 

Residential Populated Area (Operable Unit No. 9) 

Standard, 

Requirement, Criteria, 

or Limitation 

Citation 

Potentially 

Applicable 

Potentially 

Relevant and 

Appropriate 

Description Comments 

SIIMMARY OF POTENTIAL CHEMICAL-SPECIFIC ARARs/TBCs 

1. Clean Air Act, 

National Primary and 

Secondary Ambient Air 

Quality Standards 

2. Colorado Ambient 

Air Quality Standards 

3. Colorado Air Pollution 

Prevention and Control 

Act, Regulation 8 

42 USC Sect. 7401-

7642, 40 CFR Part 

50 

5 CCR 1001 

5 CCR 1001-14; 5 

CCR 1001-10 Part 

C (1), Regulation 8 

Yes 

Yes 

Yes 

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 

addresses only major sources. See Colorado Air 

Pollution Prevention and Control Act conceming 

applicability of requirements implemented 

through the SIP. 

F*rimary and secondary standards for PM 10 in 

ambient air. Federal and State TSP standards have 

been replaced with PM 10 and PM2.5 standards. 

Regulation No. 8 sets emission limits for lead. 

Applicants are required to evaluate whether the 

proposed activities would result in an exceedance 

ofthis standard. 

Emissions associated with proposed remedial 

action at individual properties will be limited 

to fugitive dust emissions associated with 

earth moving activities during soil removals. 

These activities will not constitute a major 

source. Federal NAAQS more stringent than 

State standards may be applicable. 

Compliance with these standards will be 

addressed in the Fugitive Emissions Dust 

Control Plan. (See #10) | 

Compliance with ambient air standards will 

be achieved by adhering to a Fugitive 

Emissions Dust Control Plan prepared in 

accordance with Regulation No. 1 (see #10). 

This plan will discuss monitoring 

requirements, if any, necessary to achieve 

these standards. 

Fugitive dust emissions are expected to be of 

limited nature, occur in isolated areas and for 

short periods oftime. Lead emissions may 

occur but are not expected to exceed the 

emission levels for lead. Compliance with 

Regulation No. 8 will be achieved by 

adhering to a fugitive emissions dust control 

plan prepared in accordance with Regulation 

No. 1 (see #10). This plan will discuss 

monitoring requirements, if any, necessary to 

achieve these standards 

F:\MyFiles\Documems\WP\Cgou9\ARARS.wpd Page 1 of 5 September 2, 1999 
SUMMARY OF POTENTIAL ARARS (Continued) 

Standard 

Requirement, Criteria, 

or Limitation 

Citation 

Potentially 

Applicable 

Potentially 

Relevant and 

Appropriate 

Description Comments 

SUMMARY OF POTENTIAL LOCATION-SPECIFIC ARARs | 

4. Resource 

1 Conservation and 

Recovery Act (RCRA), 

Subtitle D 

5. Executive Order 

11593 - Protection and 

Enhancement of the 

Cultural Environment 

6. National Historic 

Preservation Act 

(NHPA) 

7. The Historic and 

Archaeological Data 

1 Preservation Act of 

1974 

40 CFR Part 

258.10-15 

16 USC 470 

16USC§470et 

seq.; 40 CFR § 

6.301(b); 36 CFR 

Part 63, Part 65, 

Part 800 

16 USC 469 

40 CFR § 6.301(c) 

No 

Yes 

Yes 

Yes 

Yes Facilities where treatment, storage or disposal of 

solid waste will be conducted must meet certain 

location standards. These include location 

restrictions on proximity to airports, floodplains, 

wetlands, fault areas, seismic impact zones, and 

unstable areas. 

Federal agencies directed 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 required. 

Expands historic preservation programs to 

minimize harm to National Historic Landmarks; 

requires preservation of resources included in or 

eligible for listing on the National Register for 

Historic Places (NRHP). 

Establishes procedures to preserve historical and 

archeological data that might be destroyed 

through alteration of terrain as a result of a 

federal construction project or a federally 

licensed activity program. 

May be relevant and appropriate if interim 

disposal is conducted or if an onsite 

repository is necessary. 

See #6 below. 

This Act is applicable within the Leadville 

National Historic Landmark District. A 

Programmatic Agreement exists between the 

EPA, the Advisory Council on Historic 

Preservation, and the Colorado State Historic 

Preservation Officer in accordance with 

Section 106 and 110(f) of NHPA. 

Remedial Activities may affect historical 

and/or archeological data. A cultural 

resources survey will be performed to 

identify and evaluate all historic properties 

which may be affected by remedial 

activities. || 

F:\MyFiles\Dociiniems\WP\Cgou9\ARARS.wpd Page 2 of 5 September 2, 1999 
SUMMARY OF POTENTIAL ARARS (Continued) 

Standard, 

Requirement, Criteria, 

or Limitation 

8. Colorado Historical, 

Prehistorical, and 

Archaeological 

Resources Act 

9. Colorado Register of 

Historic Places 

Citation 

Colorado Revised 

Statutes (CRS) §§ 

24-80-401 to 411, 

24-80-1301 to 1305 

CRS §§24-80-101 to 

108 

Potentially 

Applicable 

No 

Unknown 

Potentially 

Relevant and 

Appropriate 

Unknown 

— 

Description 

Establishes procedures and requires a permit 

for investigation, excavation, gathering, or 

removal from the natiu-al state ofany 

historical, prehistorical, or archaeological 

resources on state lands for the benefit of 

recognized scientific or educational 

institutions. Also requires an excavation 

permit and notification if human remains are 

found on state land. 

Establishes requirements for protecting 

properties of historical significance. 

Comments 

May be relevant and appropriate if 

archaeological resources are removed or 

human remains discovered during remedial 

activities; coordination with state 

archaeologist required, but no permit is 

needed within the Superfund site. 

May be applicable if remedial acfions impact 

any property listed on the Register of 

Historic Places. 

SUMMARY OF POTENTIAL ACTION-SPECIFIC ARARs/TBCs 

10. Colorado Air 

Pollution Prevention and 

Control Act, Fugitive 

Dust Control 

Plan/Opacity, Regulation 

No. 1 

11. Colorado Air 

Pollution Prevention and 

Control Act, APENs 

Regulation No. 3 

12. Colorado Air 

Pollution Prevention and 

Control Act, Odors, 

Regulation No. 2 

5 CCR 1001-3; 

§ in. D. l.b,c,d. 

§ 

lII.D.2.a,b,c,e,f,g 

Regulation 1 

5 CCR 1001-5, 

Regulation 3 

5 CCR 1001-4 

yes 

Yes 

Yes — 

Regulation No. 1 provisions conceming 

fugitive emissions for constmction activities, 

storage and stockpiling activities, haul roads, 

haul tmcks, and tailing ponds. 

Establishes emissions control regulations for 

constmction or modification of stationary 

sources. 

Applies to any remedial action that may 

create regulated odors. 

Only provisions under Regulation 1 

conceming fijgitive emissions for 

constmction activities, including soil 

renioval, storage, transport and stockpiling 

(5 CCR 1001-3; Sections III.D.2.b,c,e,f,g.), 

are applicable. 

Substantive requirements ofan Air Pollution 

Emission Notice (APEN) are applicable if 

the removal actions disturb contaminated 

soil. An APEN will be filed, although 

pemiitting requirements such as this am not 

typically required under CERCLA. 

Planned remedial actions are not expected to 

create regulated odors. 

F:\MyFiIes\Documents\WP\Cgou9\ARARS.wpd Page 3 of 5 September 2, 1999 
SUMMARY OF POTENTIAL ARARS (Continued) 

ll 

Standard, 

Requirement, Criteria, 

or Limitation 

13. Colorado Air 

Pollution Prevention and 

Control Act, 

Requirements for LeadBased Paint Abatement 

Regulation No. 19 

14. Solid Waste Disposal 

Act (SWDA) as amended 

by RCRA, Criteria for 

Classification of Solid 

Waste Disposal Facilities 

and Practices (Subtitle D) 

15. SWDA as amended 

by RCRA Subtitle C 

16. Hazardous Materials 

Transportation Act, 

Regulations 

17. Colorado Noise 

Abatement Act 

18. Colorado Water 

Quality Control Act 

Stormwater Discharge 

1 Regulations 

Citation 

Colorado Revised 

Statutes §§ 25-7-

1101-1107, 

Regulation 19 

42 USC Sect. 6901-

6987, 

40 CFR Part 257 

42 USC Sect. 6901 -

6987, 

40 CFR Part 264 

49 USC Sect. 1801 -

1813,. 

49 CFR Parts 107, 

1710177 

CRS §§ 25-12-101 

to 108 

5 CCR 1002.2 

Potentially 

Applicable 

Yes 

Yes 

Yes 

Unknown 

Yes 

Yes 

Potentially 

Relevant and 

Appropriate 

— 

— 

— 

Description 

Establishes procedures and requirements for 

lead-based paint abatements greater than 2 

square interior feet and 10 square exterior 

feet, including training and accreditation of 

individuals and firms engaged in lead- based 

paint activities and work practice standards 

for performing such activities. 

Establishes criteria for use in determining 

which solid wave disposal facilities and 

practices pose a reasonable probability of 

adverse effects on health. 

Regulates handling, transportation, storage 

and disposal of hazardous wastes. 

Regulates transportation ofhazardous 

materials. 

Establishes maximum permissible noise 

levels for particular time periods and land 

use zones. 

Establishes stormwater control requirements 

for constmction activities. 

Comments 

Applicable when lead-based paint abatement 

activities are performed. On-site CERCLA 

actions are exempt from administrative and 

fee requirements. Subject to project-specific 

variance per Sections IV.G and V.M of 

Regulation 19. 

Substantive requirements may be applicable 

or relevant and appropriate to the 

consolidation of soil removed from 

Potentially applicable for lead-based paint 

waste debris resulting from remediation. 

Applicable only if the remedial action 

involves off-site transportation ofhazardous 

materials. The regulations affecting 

packaging, labeling, making, placarding, 

using proper containers, and reporting 

discharges of hazardous materials would be 

potential ARARs. 

Applicable if constmction activities occur in 

residential areas. 

Potentially applicable if constmction 

activities occur as part ofthe remedial 

action. 

F:\MyFUes\Documents\WP\Cgou9\ARARS.wpd Page 4 of 5 September 2, 1999 
Standard, 

Requirement, Criteria, 

or Limitation 

19. Colorado Solid 

Waste Disposal Sites 

and Facilities Act 

20. Colorado 

Hazardous Waste 

Regulations 

21. Colorado Mined 

Land Reclamation Act 

22. Colorado Primary 

Drinking Water 

Regulation 

Citation 

6 CCR 1007-2 

6 CCR 1007-3, Part 

264: Section 

264.301, (g),(h), 

(i) and (j); Section 

264.310(a)(1) 

through (a)(4); 

Section 264.310, 

(b)(1) and (b)(5) 

CRS 34-32-101 to 125; 

Rule 3 of Mineral Rules 

and Regulations 

5 CCR 1002, CRS 

25-1-107, Section 

7.3.2 

Potentially 

Applicable 

Yes 

No 

No 

No 

Potentially 

Relevant and 

Appropriate 

— 

Yes 

Yes 

Yes 

Description 

Establishes standards for licensing, locating, 

constructing and operating solid waste 

facilities. 

Specific provisions ofSection 264.301 

concem mn-on control, run-off control, 

management of mn-on and mn-off control 

systems and wind dispersal. Specific 

provisions ofSection 264.310 concem 

placement of a cover to minimize 

infiltration, minimize maintenance, promote 

drainage and minimize erosion and 

accommodate settling. 

Regulates all aspects of land use for mining, 

including the location of mining operations 

and related reclamation activities and other 

environmental and socio-economic impacts. 

Requirements to control lead and copper 

concentrations in tap water. 

Comments 

Substantive requirements may be applicable 

or relevant and appropriate to the 

consolidation of soil removed from 

residential areas in an on-site repository. 

These specific provisions of the hazardous 

waste regulations may be relevant and 

appropriate in certain circumstances 

depending on site specific conditions. The 

determination of whether such requirements 

will be both relevant and appropriate to the 

activities to be undertaken in OU9 will be 

based on best professional judgement and is 

conducted on a site specific basis taking into 

account the physical nature and location of 

the media involved, whether the 

requirements are well suited to the site 

conditions, and other factors. 

No mining or reclamation activities are 

planned as part of remedy. If mining 

activities are performed, then substantive 

requirements of selected portions of Rule 3 

regarding Reclamation Measures, 

Water-General Requirements (except 

portions relating to sitewide surface and 

groundwater), wildlife and revegetation may 

be applicable. However, certain provisions of 

these regulations may be relevant and 

appropriate to the 0U9 remedial action. 

Tap water sampling requirements are 

relevant and appropriate. 

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