The largest open-pit mine ever excavated proved that low-grade porphyry copper could be mass-mined at world scale, supplying a significant fraction of U.S. copper demand through two World Wars and beyond.
Kennecott Bingham Canyon Mine
work active confidence: High status: Draft updated 2026-08-11
Summary
The Bingham Canyon Mine is the largest open-pit copper mine in the world by volume excavated — roughly 1.2 km deep and 4 km wide, visible from space. Copper is foundational infrastructure: electrical wiring, plumbing, motors, and now EV powertrains and grid cables.
Impact
Copper is foundational infrastructure: electrical wiring, plumbing, motors, and now EV powertrains and grid cables. Bingham Canyon's scale drove down copper prices in the early twentieth century and supplied a significant fraction of U.S. copper demand through both World Wars and into the postwar industrial expansion. The open-pit mass-mining template developed here became the standard approach for large copper, gold, and iron mines globally — the same techniques now dominate the industry worldwide.
What It Took
Jackling and his colleagues developed and industrialized mass-mining: drill-blast-haul at scale, concentrator technology capable of handling low-grade ore, and the logistics to move millions of tons of rock economically. The technical achievement was not just building a larger mine but proving that ore too dilute for conventional methods could support enormous industrial throughput.
The National Historic Landmark designation reflects this global influence on mining practice, not merely regional historical significance.
Utah Context
The mine sits in a canyon in the Oquirrh Mountains 25 miles southwest of Salt Lake City. Utah's mineral wealth anchored Bingham Canyon's long operation, and the mine's economic relationship with the Wasatch Front shaped the region's industrial character throughout the twentieth century. The site's environmental footprint — tailings ponds, groundwater contamination, air quality concerns — has been a persistent presence in Utah's environmental history and continues to generate remediation costs.
Evidence
- USGS Porphyry Copper Deposits of the World, 2008 — the Bingham row (OFR 2008-1155) · https://doi.org/10.3133/ofr20081155 — deposit tonnage and grades, and a 1906 mining start date, from the USGS's global porphyry inventory.
- Kennecott Utah Copper — History · https://www.kennecott.com/history — source record
- National Register / National Historic Landmark nomination, Bingham Canyon Mine (NRIS reference 66000736) · https://npgallery.nps.gov/AssetDetail/NRIS/66000736 — the NPS record behind the landmark designation; also the source of the district's 1904–1982 production totals and of the credit to Daniel C. Jackling.
- Hyde, Copper for America (1998) — industry history
Open Questions
- The USGS source records a deposit-wide average copper grade across total production, reserves, and resources, not the grade of ore currently mined. A primary operating source is still needed before asserting a current mined-grade figure.
- The NPS nomination dates the operation's initiation to 1904 — Utah Copper Company organized in 1903, Copperton Mill completed in 1904 — while the USGS database gives a 1906 start of mining, the date used here. The records do not resolve whether they describe different milestones.
- Precise production tonnage figures for the WWII contribution would strengthen the wartime impact claim.
- The 2013 landslide recovery timeline and lessons learned are not yet documented here.
- Environmental remediation scope and cost are worth documenting more precisely.