Kennecott Copper Corporation, Leaching Plant, On Copper River & Northwestern Railroad, Kennicott, Valdez-Cordova Census Area, AK

Significance: The original leaching plant (now the south end of the building) was constructed in 1915 and went into production the next year. The first four leaching tanks could process 300 tons of ore per day. Within a year the number of leaching tanks was doubled with additions to the north end of the plant. Leaching could not recover all of the copper. In 1923, a small flotation plant was installed at the north end of the leaching plant to process the small ore particles known as slimes and sands.
Unprocessed Field note material exists for this structure: N1050
Survey number: HAER AK-1-E
Building/structure dates: 1915 Initial Construction
Building/structure dates: 1923 Subsequent Work
Building/structure dates: 1935 Subsequent Work
Building/structure dates: 1938 Subsequent Work
National Register of Historic Places NRIS Number: 78003420