Class III Cultural Resources Survey & Historic Research at Iron King Mine & Humboldt Smelter, EPA, Humboldt, Arizona

ACS recently completed a Class III cultural resource survey and historic building survey at the Iron King Mine and Humboldt Smelter, located just outside of Humboldt, Arizona. The survey was conducted in compliance with Section 106 of the National Historic Preservation Act on behalf of the Environmental Protection Agency (EPA) for their Remedial Investigation/Feasibility Study at this Superfund site. As part of this study, ACS conducted archival research and interviewed several individuals who had knowledge of the historic mine and smelter operations. As the project area is within a Superfund site with ground contamination of arsenic and lead at levels exceeding health and safety standards, all field crew members had current certification of 24-40 hours of Hazwoper training prior to conducting fieldwork.

Before field work began, the Environmental Protection Agency (EPA) provided ACS a dataset which included project area shapes and a list of known contaminated zones.  Using a GIS, these data, together with additional project data created by ACS were incorporated into the Geodatabase, allowing the field crew to better prepare for encountering known contaminates and archaeological features.  Throughout field work, a sub-meter accurate GPS was used to map all of the cultural features and update the location of the contaminated zones.  Following field work, the data collected from the survey was post-processed allowing for even higher GPS accuracy. This data was used in the production of all the maps that were included in the report. 

The historic building survey documented the Humboldt Smelter and Iron King Mine buildings and structures that remain and produced a historic context for the properties to document and evaluate their significance. The Class III cultural resource survey documented all features and cultural remains within the Iron King Mine and Humboldt Smelter property boundaries, including the archaeological remains of an early homestead.

The historic Humboldt Smelter played a significant role in the historical development of the Big Bug Mining District from 1870 to 1937 when the smelter ceased operations. In addition to a variety of buildings and structures directly related to the smelting operations, the property also once contained Nob Hill, a residential neighborhood where the managers and executives lived. Worker housing on the property consisted of several bunkhouses and small dwellings below Nob Hill. Although none of the residences and few of the smelter buildings and structures remain at the Humboldt Smelter property today, one of the smelter stacks still can be seen from the adjacent highway, just to the south of Humboldt.

Iron King Mine was also significantly involved in the development of the Big Bug Mining District, beginning with the discovery of an ore outcropping in 1880. A variety of mining operations took place at this site through time and by 1906 there was a miner’s camp of about 300, including 140 employees of the mine. Ownership of the mine passed to several different people and by its final years in the late 1960s before it eventually closed, the mine produced almost all the lead and zinc mined in Arizona. Most of the historic buildings related to the Iron King Mine operations no longer exist. A few remain, but none from its earliest days.

The study ACS conducted was the first of its kind for these historic properties. Surprisingly, the histories of the Iron King Mine and Humboldt Smelter and their role in the development of mining in the Big Bug district have received little attention in past literature. In addition to the property inventories ACS conducted, the historic contexts presented in the report provide an important contribution to the historic literature for this region and will serve as a resource for future researchers and historians.