Superfund Information Systems: Site Profile

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The former Iron King Mine and Humboldt Smelter lie within the Town of Dewey-Humboldt, in the high desert of central Arizona, about 85 miles north of Phoenix. The Agua Fria River flows south through portions of the eastern section of the former Humboldt Smelter property.

There are two major contributors to contamination at the Iron King Mine / Humboldt Smelter (IKHS) site. First, the former Iron King Mine where mining operations began in the late 1890s.  The mine propertyis about 150 acres and is located west of Highway 69. Operators extracted, milled, and concentrated solid rock ores for lead, zinc, copper, gold, and silver between about 1934 and 1970. Smaller mining facilities operated between 1906 and 1934.

Second, the former Humboldt Smelter where mining and smelting operations began in the late 1870s. The smelter site is about180 acres and is located about 0.5 miles east of Highway 69. After small-scale operations in the late 1800s, the Humboldt Smelter purified copper from mine ores between 1906 and about 1937. Most production took place during World War I. Later, in the 1950s and 1960s, small processing operations attempted to recover metals from materials brought to the old smelter property.

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What Is the Current Site Status?

EPA listed the site on the Superfund program’s National Priorities List (NPL) in 2008.



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Emergency Response and Removal

Site activities have also included three removal actions, or short-term cleanups to address immediate threats to human health and the environment, to address risks in residential yards. In addition, a potentially responsible party (PRP)-lead removal action by Ironite in 2006 removed contaminated soil from four residential properties.

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