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Iron King Mine And Humboldt Smelter

EPA #: AZ0000309013

State: Arizona(AZ)

County: Yavapai

City: Dewey-Humboldt

Congressional District: 01

Other Names:

Bulletin Board

Description and History

NPL Listing History

NPL Status: Proposed

Proposed Date: 03/19/08

Final Date: 08/03/08

Deleted Date:

The Site is a combination of sources and releases from two areas: the Iron King Mine and the Humboldt Smelter. A portion of the Town of Dewey-Humboldt is situated between the mine and the smelter. Three waterways (Chaparral Gulch, Galena Gulch, and Agua Fria River) also transect the Site.

The Iron King Mine area covers approximately 153 acres. The majority of this area is covered by tailings and waste rock piles. There are five retention ponds, at least five mine shafts, a collapsed mine shaft (glory hole), and areas of stained soil. The Iron King Mine was an active mine from 1904 until 1969. The mine was expanded in 1936 to remove lead, gold, silver, zinc, and copper from underground. A 140-ton mill was erected to crush ore and was expanded to 225-ton capacity in 1938. A cyanide processing plant was added to the site in 1940 to treat the mill tailings to enhance precious metal recovery. Waste rock and tailings were deposited in large piles adjacent to actual mine property boundaries. More recently, the mine tailings from the site have been used to create fertilizer.

The Humboldt Smelter occupies approximately 182 acres. This area is covered in approximately 763,800 square feet of yellow-orange tailings, over 1 million square feet of grey smelter ash, and 456,000 square feet of slag. The Humboldt Smelter operated from the late 1800s until the early 1960s. The original smelter burned down in 1904 and a smelter that processed 1,000-tons of ore per day was rebuilt in 1906. This smelter operated until 1918 and then intermittently between 1922 and 1927. The smelter reopened in 1930.

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Contaminants and Risks

Contaminated Media:

Groundwater

Groundwater

Surface Water

Surface Water

Air

Air

Soil and Sludges

Soil and Sludges

The contaminants of concern at this site are arsenic, lead, and sulfate. The primary sources of contamination are:
• Iron King Mine Main Tailings Pile and Impoundment/Ponds
• Iron King Mine Small Tailings Pile
• Humboldt Smelter Ash Pile
• Humboldt Smelter Impoundment/Pond
• Humboldt Smelter Tailings Pile
• Lower Chaparral Gulch

The locations of these source areas are shown on the map titled "Site Features" below. These sources contain average arsenic and lead levels from one to two orders of magnitude greater than average background arsenic and lead levels. Exposure to these metals could present a health risk if a person is in contact with them over a long period of time. EPA recommends that residents, especially children and the elderly, limit or avoid contact with soils and any water in these areas, and obey EPA caution signs until these areas can be addressed through cleanup actions. Residents should limit or avoid spending time in Chaparral Gulch as tailings have been deposited along most of its length.

Human Health and Ecological Risk Assessments
EPA conducted a human health risk assessment to evaluate the potential harm to residents posed by site contaminants. The risk assessment indicates that contamination at the site could pose health risks (cancer risks and noncancer hazards) if no cleanup action is taken.

EPA conducted an ecological risk assessment to evaluate whether potential exposure to contaminants could harm plants or animals. The assessment found that contamination poses risks to many plant and animal groups (for example: mammals, birds, reptiles, and aquatic organisms).

The results of the RI indicate a need to take cleanup actions to protect human health and the environment. The next phase in the Superfund process is the Feasibility Study, which focuses on developing cleanup options that will reduce the health risks posed by the site to people, animals, and plants.

Who is Involved


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Investigation and Cleanup Activities

Initial Actions
A potentially responsible party (PRP)-lead removal action by Ironite was conducted in 2006 to remove contaminated soil from four residential properties. Staff from EPA’s Office of Emergency Response supervised the sampling and removal of the contaminated soil conducted by the PRP’s contractor, Brown and Caldwell.

Initial Action

Initial Actions
Portions of this Site were regulated under the Arizona Department of Environmental Quality (ADEQ)’s Voluntary Remediation Program. In September 2007, EPA received a response from Arizona Governor Napolitano consenting to the placement of the Site on the National Priorities List (NPL). On 19 March 2008, EPA formally proposed the Site to the NPL, commonly called the Superfund List.


Placing the site on the NPL allows EPA to use federal resources to conduct cleanup activities at the site, including investigating the sources of contamination and determining what measures may be necessary to protect human health and the environment.

EPA received comments from the community on EPA’s NPL proposal for this Site. EPA reviewed and considered each comment and placed the site on the NPL on September 3, 2008.

    Site Studies

    Site Studies
    During summer 2008, EPA initiated the Remedial Investigation or "RI". The primary objectives of the RI are to determine the nature and extent of contamination and to gather sufficient information so that EPA can select a remedy that eliminates, reduces, or controls risks to human health.
    During the course of the RI, EPA identified five Areas of Interest (AOI):
    • Iron King Mine – Includes the Iron King Mine Proper Area, Iron King Mine Operations Area, Former Fertilizer Plant Area, Salvage Yard, and ancillary associated properties.
    • Humboldt Smelter – Includes several abandoned buildings, a smelter stack, a tailings pile, a smelter ash pile, and a slag pile.
    • Waterways – Includes the Chaparral Gulch, Galena Gulch, Agua Fria River, and adjoining drainage channels and outfalls.
    • In-Town Soil – Includes residential, background, and ancillary properties
    • Ground Water – Includes shallow alluvium and deep bedrock ground water

    EPA conducted the following tasks as part of the RI:
    • Collected over a thousand soil samples in the mine and smelter areas, residential yards, and the Humboldt Elementary School
    • Collected background data for site contaminants
    • Conducted water quality monitoring at six new groundwater monitoring wells and over 50 private well and tap water locations
    • Conducted a storm water evaluation
    • Developed volume estimates for waste and tailings piles
    • Collected surface water samples along the Agua Fria River, the Galena Gulch, and the Chaparral Gulch
    • Conducted air monitoring at ten air monitoring stations for 11 months
    • Conducted an Ecological Habitat Survey
    • Conducted a Cultural Resource and Historic Building Survey
    • Conducted a Wetlands Assessment
    • Collaborated with the University of Arizona on three site research projects
    • Initiated a Reuse Assessment

    The results of the RI are compiled in the RI Report, which is an in-depth document that identifies source areas, defines the nature and extent of contamination, and presents a summary of human health and ecological risks. A copy of the RI Report is available at the Dewey-Humboldt Library and EPA Superfund Records Center and can also be found electronically below. A summary of the RI results is presented in the factsheet dated April 5, 2010, which can also be found below.

    Please send any questions or comments on the RI Report to Monika O'Sullivan, contact information provided below.

      Site Studies

      Site Studies
      Data collected during the RI influences the development of cleanup options for the Site. The detailed development and analysis of cleanup options is called the Feasibility Study. During the Feasibility Study, the advantages and disadvantages of each cleanup method are explored. EPA, working in conjunction with ADEQ, will propose a recommended cleanup option for the Site in the Proposed Plan, which is accompanied with a public comment period. The Feasibility Study is currently underway.

      Cleanup Results to Date

      Graph image

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      Potentially Responsible Parties

      Potentially responsible parties (PRPs) refers to companies that are potentially responsible for generating, transporting, or disposing of the hazardous waste found at the site.


      The term "Potentially Responsible Parties" or "PRPs" refers to companies or individuals who are potentially responsible for generating, transporting, or disposing hazardous substances associated with the site. PRPs also include current owners and operators of the site and parties who were owners or operators during a time of disposal.

          As part of the Superfund process, EPA identifies those parties that are "potentially responsible parties" who fall into one or more of the above categories of PRPs, and then may negotiate with the PRPs to perform cleanup activities under EPA oversight and/or help pay EPA's response costs. EPA has conducted a search for parties associated with the Iron King Mine-Humboldt Smelter Superfund Site and on November 19, 2009, issued a General Notice Letter to 14 parties advising them of their status as PRPs under CERCLA.

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      Documents and Reports

      Hide details for Community InvolvementCommunity Involvement
      10/01/09Community Involvement Plan - Iron King Mine – Humboldt Smelter Site
      04/27/10Iron King Mine - Humboldt Smelter Superfund Site - Presentation
      08/31/11Public Meeting Presentation
      09/01/11Frequently Asked Questions
      Hide details for Fact SheetsFact Sheets
      08/01/05U.S. EPA PLANS REMOVAL ASSESSMENT
      01/01/06U.S. EPA Completes Removal Assessment
      04/01/08Iron King Mine-Himboldt Smelter Proposed for Superfund List
      08/01/08EPA Begins Site Investigation
      01/30/09EPA Conducts Ambient Air Sampling
      05/01/09Chaparral Gulch Show Elevated Arsenic
      10/02/09Investigation Report Due This Winter
      02/01/10Safe Gardening in Dewey-Humboldt
      02/16/10Federal, State, and Local Environmental Resources
      04/13/10EPA Completes Remedial Investigation - Additional Residential Sampling Offered
      11/04/10Cleanup Documents Available for Review
      04/12/11Residential Soil Sampling Completed Ahead of Upcoming Yard Cleanup
      08/12/11Residential Yard Cleanup To Start this Fall
      Hide details for ImagesImages
      07/01/10Iron King Mine – Humboldt Smelter Superfund Site (Frequently Asked Questions)
      Hide details for MapsMaps
      05/01/08Investigation Areas - Iron King Mine - HS
      01/20/09Site Map
      Hide details for Technical DocumentsTechnical Documents
      08/01/08Data Presentation Air- Ambient Air Data Summary Table
      01/01/09Data Summary Air - Ambient Air Data Summary Table - December 2008/January 2009
      02/04/09A Cultural Resource and Historic Building Survey for a Remedial Investigation/Feasibility Study at the Iron King Mine-Humboldt Smelter Superfund Site
      02/04/09BIOLOGICAL EVALUATION OF THE IRON KING MINE - HUMBOLDT SMELTER SUPERFUND SITE
      03/01/09TEOM - Particulate Monitoring Graph
      07/01/09Reusing Superfund Sites - Summary Overview
      11/01/09RIPARIAN EVALUATION AND JURISDICTIONAL DETERMINATION
      03/01/10Remedial Investigation Report
      03/01/10Remedial Investigation Report (Appedix A)
      06/01/10Reuse Assessment for Iron King Mine - Humboldt Smelter Superfund Site
      10/11/10Data Evaluation Summary Report Addendum II
      10/13/10Remedial Alternatives Evaluation Technical Memorandum
      10/20/10Cover Alternatives Evaluation for Iron King Main Tailings Pile

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      Community Involvement

      Public Meetings: The EPA recognizes that Americans have the right to be involved in the government decisions that affect
      their lives. EPA’s experience has been that when the public is involved in EPA’s work, the cleanup process results in a better outcome and a more robust remedy.

      At the Iron King Mine – Humboldt Smelter Superfund Site, EPA’s Community Involvement Program helps citizens participate throughout the cleanup process, including the investigation phase and the remedy selection phase. The goals of EPA’s Community Involvement Program are to:
      1. Provide opportunities for the public to become actively involved
      2. Meet the community’s information needs
      3. Incorporate issues and concerns into cleanup decisions
      4. Give feedback to the public on how their issues and concerns were incorporated into the cleanup work

      EPA and ADEQ have a number of ways for the community to become more knowledgeable about and involved with the Iron King Mine – Humboldt Smelter Superfund Site.

      Community Involvement Plan
      The Iron King Mine – Humboldt Smelter Superfund Site Community Involvement Plan provides a detailed explanation of how EPA and ADEQ will encourage public participation in the cleanup decision-making process. It is a flexible plan that organizes both EPA’s and ADEQ’s efforts but can change
      based on new community needs. A copy is located at the Dewey-Humboldt Town Library and is also available below.

      Community Advisory Group
      A Community Advisory Group is stakeholder forum where individuals or those representing groups meet together to learn more about the Superfund cleanup process, and to provide information, issues and
      concerns to EPA and ADEQ. Membership in the group does not require a technical background.

      The CAG is a self-forming and voluntary group. Although EPA and ADEQ do not manage the group, EPA can provide limited support, such as making copies, providing documents, rental meeting rooms, paying for meeting notices, etc. The biggest advantage of a CAG is that it meets regularly and at intervals that are usually far more frequent than EPA’s event-driven meetings. In this way, attendees can get the
      latest information and can talk directly to EPA and ADEQ representatives.

      If you are interested in participating in a CAG, please send an email with your contact information to dhsmelter@gmail.com (Note: This e-mail address is managed independently by a Dewey-Humboldt resident and is not associated with EPA).

      Technical Assistance Grant Available
      EPA offers a Technical Assistance Grant (TAG) to a community affected by a Superfund site by providing money for activities to help the community participate in decision making. An initial grant up to $50,000 is available to a qualified community group so they can contract with an independent
      technical advisor to interpret and help the community understand technical information about their site.
      After the independent technical advisor reviews the site related documents, the advisor can help the community formulate its issues and concerns, and communicate them effectively to EPA.

      To qualify, the TAG recipient must be or become an incorporated non-profit organization. EPA can pay for the costs of incorporation. The group must establish a bank account to receive the funds and create a record of how they spent the funds. EPA staff are available to help a group through the application process. Interested community members may contact David Cooper (contact information below).

      Mailing Lists
      If you would like to be added to the site mailing list, please contact David Cooper (contact information below) or call the toll free hot-line (800) 231-3075 and leave a message with your name and address. EPA also sends periodic updates to the site email list. If you would like to be added to the email list, please contact Monika O'Sullivan (contact information below).

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      Public Information Repositories

      File cabinet

      The most complete collection of documents
      is the official EPA site file, maintained at
      the following location:

      Superfund Records Center

      Mail Stop SFD-7C

      95 Hawthorne Street, Room 403

      San Francisco, CA 94105

      (415) 820-4700

      Enter main lobby of 75 Hawthorne street,
      go to 4th floor of South Wing Annex.

      The public information repositories for
      the site are at the following locations:

      Dewey-Humboldt Town Library 2735 N. Corral Street Dewey-Humboldt, AZ 86329 (928) 632-5049 http://yavapailibrary.org/dhl.htm

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      Contacts

      Name Phone Number Email Address
      EPA Site Manager Monika OSullivan 415-972-3111 OSullivan.Monika@epamail.epa.gov Mail Code SFD62
      75 Hawthorne Street
      San Francisco, CA 94105
      EPA Community
      Involvement Coordinator
      David Cooper 415-972-3245
      1-800-231-3075
      Cooper.David@epamail.epa.gov Mail Code SFD63
      75 Hawthorne Street
      San Francisco, CA 94105
      EPA Public Information
      Center
      415-947-8701 r9.info@epa.gov
      State Contact Tina LePage 602-771-4293 Lepage.tina@azdeq.gov 1110 West Washington St.
      Phoenix, AZ 85007
      PRP Contact
      Community Contact
      Other Contacts
      After Hours
      (Emergency Response)

      US EPA

      (800) 424-8802

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