Three Kids Mine

The Hydro pit, Hulin pit, three tailings ponds, overburden, flotation tank foundations, and a portion of the ore yard are visible in this aerial photograph of the Three Kids Mine site.
Features of the Three Kids Mine site include open pits, tailings ponds,
overburden, flotation tank foundations, and ore yard.

What's Next?
Background
Current Status
Downloadable Documents
Recent News
Additional Information


What's Next?

NDEP hosted an open house Community Information Meeting in March 2023 in Henderson, Nevada. This provided the community with an opportunity to provide input on the Proposed Plan for the cleanup of environmental contamination at the Three Kids Mine site. In November 2023, NDEP issued the Record of Decision explaining the selected cleanup alternative for the site. The Perimeter Air Monitoring Plan describes how air will be monitored during site cleanup activities, which began in May 2024.

Background

The Three Kids Mine was an open-pit manganese mine discovered in Clark County, Nevada in 1917. During its early years of operation, which coincided with World War I, manganese from the mine was used in military weapons and equipment. With the end of the war, and the subsequent drop in demand for manganese, mining activities slowed and the Three Kids Mine remained nearly dormant for the next several years.

In 1942, a mill was constructed for on-site processing of manganese ore to help meet the demand for manganese, which had been reignited as a result of World War II. Around this same time, the unrelated Basic Magnesium Incorporated complex, also located in Clark County, Nevada, produced magnesium for the war effort. However, the end of the war once again represented a decline in activity at the Three Kids Mine, and the mill was closed in 1944.

Site activities remained limited up until 1951, when the mill was remodeled and subsequently reopened. The mine and mill continued producing manganese until all open pits were exhausted, and in 1961, all site operations were permanently discontinued. Reserves of lead and manganese that had been stockpiled on-site were sold in the years that followed, and in the early 1980s, a few parcels from the property were sold and redeveloped. Key features of the former Three Kids Mine include open pits, waste rock, ore yard, mill site, and tailings ponds.


Current Status

Several assessments and studies of the Three Kids Mine site took place in the late 90s through early 2000s. In 2007, a Phase I Environmental Site Assessment (ESA) of the site was conducted. The Phase I ESA identified recognized environmental conditions (RECs) at the site through public records review, interviews with knowledgeable parties, and physical site inspections. RECs include dusts, residues, and processing wastes containing lead, arsenic, manganese, and petroleum.

On July 25, 2014, the federal Three Kids Mine Remediation and Reclamation Act was enacted. This legislation provides a framework by which Federally-owned land within the 1,165-acre Three Kids Mine site can be conveyed through the City of Henderson Redevelopment Agency for site assessment, remediation, and reclamation by a designated responsible party. Land transfer was completed in February 2024. Major project milestones include the completion of a Remedial Investigation and Feasibility Study to identify site contaminants and evaluate cleanup alternatives, as well as the issuance of a Record of Decision for the selected cleanup approach. Documents summarizing these activities can be downloaded from the links below.

Air monitoring equipment at the Three Kids Mine.
Air monitoring equipment at the Three Kids Mine.

Downloadable Documents

Site Cleanup

Perimeter Air Monitoring Reports

Inspection Reports

Progress Reports

Perimeter Air Monitoring Plan, Revision 1 (PDF, 7.2 MB)

Remedial Design Modification No 2 Expansion of Central Valley Area, Revision 1 (PDF, 2 MB)

Remedial Design Modification No 1 Expand Closure Units to Central Valley Area (PDF, 6 MB)

Remedial Design Report, Revision 1 (PDF, 26.08 MB)

Remedial Design Drawings (PDF, 29.15 MB)

Geotechnical Report Rev. 8-19-22 Sealed (PDF, 28 MB)

Record of Decision (PDF, 9.01 MB)

Community Involvement

Community Updates

Proposed Plan (PDF, 8.94 MB)

Frequently Asked Questions (PDF, 2.55 MB)

Fact Sheet (PDF, 2.32 MB)

March 2023 Community Information Meeting Slideshow (PDF, 4.14 MB)

Community Involvement and Participation Plan (PDF, 494 KB)

Site Assessment Reports

Corrective Action Plan - Soil and Mine Wastes, Revision 1 (PDF, 7.91 MB)

Screening Level Ecological Risk Assessment, Revision 1 (PDF, 22.3 MB)

Remedial Investigation Report, Revision 2 (PDF, 58.6 MB)

Data Validation Summary Report: Reporting of Three Kids Mine Remedial Investigation Data, Revision 2 (PDF, 60.9 MB)

Leaching Analysis Report, Revision 1 (PDF, 24.4 MB)

Screening Level Human Health Risk Assessment, Revision 1 (PDF, 9.13 MB)

Focused Feasibility Study Report – Soil and Mine Wastes, Revision 2 (PDF, 9.48 MB)

Risk Assessment Work Plan, Revision 2 (PDF, 12.3 MB)

Asbestos Survey Report - Revision 2 (PDF, 26.8 MB)

Background Soil Report, Revision 2 (PDF, 6.37 MB)

Data Validation Summary Report: Reporting of Three Kids Mine Background Study Data, Revision 1 (PDF, 890 KB)

Work Plan for Leaching Analysis of Hydro Pit Fill, Revision 1 (PDF, 8.78 MB)

Phase II Sampling and Analysis Plan, Rev. 2 (PDF, 40.9 MB)

Phase I Environmental Site Assessment (PDF, 10.9 MB)

Three Kids Mine Act

Three Kids Mine Remediation and Reclamation Act (PDF, 250 KB)


Recent News

October 28, 2024 - Asbestos removal to be complete next month as Three Kids Mine cleanup well underway - FOX5 Vegas*

November 22, 20233,000 homes to be built on top of old mine site in HendersonLas Vegas Review-Journal*

November 20, 2023 - Three Kids Mine site cleanup set to begin in 2024 as vote nears on plan for 3,000 homes - 8 News Now*

November 20, 2023Henderson City Council to vote on controversial development at old mine siteLas Vegas Review-Journal*

November 12, 2023Developers move forward on cleanup of former Three Kids Mine in Henderson - Las Vegas Sun*

October 4, 2023Henderson City Council tables Three Kids Mine housing discussion - The Nevada Independent*

October 3, 2023Henderson City Council delays controversial Three Kids Mine voteLas Vegas Review-Journal*

October 2, 2023Planned housing development on old Henderson mine has experts concerned - Las Vegas Review-Journal*

March 31, 2023Clean up plans explained for site of Three Kids Mine site near Lake Las Vegas - FOX5 Vegas*

*Disclaimer: The Nevada Division of Environmental Protection does not offer any guarantee, express or implied, regarding the accuracy, validity, or completeness of the information presented by a third-party.  Furthermore, the views or opinions expressed by a third-party do not reflect the views or opinions of the Division.


Additional Information

For more information, please contact Alan Pineda at:
alan.pineda [at] ndep.nv.gov or 702-668-3925

To request public records, please submit a Public Records Request Form.

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