The Global History of Mine Subsidence: from Butte to Kitwe – Brian J. Leech

Subsidence in Central Butte (2018) - photo by the author.
Subsidence in Central Butte (2018) - photo by the author.

Brian J. Leech is an Associate Professor of History at Augustana College. His book, The City that Ate Itself: Butte, Montana and Its Expanding Berkeley Pit (University of Nevada Press, 2018) provides an environmental and social history of Butte, through oral history and archival sources.

English civil engineer A.C. Waltham wrote in 1989 that ground subsidence, a situation where sinking, shifting land alters the built and natural environment, is “often left as the poor relation to landslides, earthquakes, volcanoes, and floods. Perhaps this is because individual cases of subsidence are usually not as dramatic as a volcanic eruption or a major landslide, and only rarely involve loss of life. Yet subsidence may rank as the most widespread ground hazard.” Mining history, particularly copper mining history, has similarly neglected subsidence, which typically takes a back seat to more dramatic and frightening industrial hazards, like smelter smoke, open-pit mines, or piles of waste.

This condition’s quiet status is perhaps because subsidence is an example of what environmental scholar Rob Nixon calls “slow violence.” Like other environmental justice issues, subsidence is a “violence that occurs gradually and out of sight.” It is “neither spectacular nor instantaneous, but rather incremental and accretive.” As with deforestation and toxic drift, subsidence’s worst effects target the poorest people. In the case of subsidence, those with the least ability to move out of the way of sliding ground become its victims.

The “slow violence” of subsidence is quite evident in the copper-mining center of Butte, Montana, U.S.A. and is the subject of an article that I’m currently writing. The federal government deemed manganese and copper to be vital war materials during World War II. The demand for these minerals led miners to tunnel closer and closer to the surface, near to people’s homes. The area around Gold, Platinum, Montana, and Colorado Streets became undermined, reportedly sinking up to twelve feet. Settling gradually occurred over an area measuring 3,600 feet, east to west, by 4,000 feet, north to south. The Butte Copper & Zinc Company and the Anaconda Company, which jointly ran the mines under central Butte, received subsidence complaints on a total of over 1500 pieces of property, mostly in Butte’s central neighborhood. About 45% of these claims were settled by the company, either through money payments or in-kind fixes. Sliding ground led the two companies most responsible for this mining, the Butte Copper & Zinc Company and the Anaconda Company, to develop a new legal protocol that released them from future liability. The Federal Housing Authority began to deny housing loans to the area, though, causing little investment in the neighborhood. Facing economic hardship during the 1980s, the subsiding area of Central Butte found a champion in the Butte Community Union, a community group that helped to revitalize the area.

Butte’s story, which suggests long-term consequences to subsidence, mirrors that of other mining communities. In Kitwe, the largest city on the Zambian Copperbelt, residents of the AMCO community faced such severe subsidence in areas above shafts that foundations became sheared and cracked. AMCO houses had originally been built for copper mine employees. The majority of those homes were still inhabited by workers or their descendants when, in the early 2000s, the Copperbelt Environmental Project began to look seriously at the area. This copperbelt project was funded largely by the World Bank and it involved the Environmental Council of Zambia and Zambia Consolidated Copper Mines—Investment Holdings, all of whom hoped to remedy historical and potential harm due to mine development. One study showed that 78 of 89 AMCO households were dramatically affected by subsidence, which, in turn, contributed to residents’ depressed socio-economic status. The Copperbelt Environmental Project eventually decided that it had to resettle the entire community. A report compiled for the World Bank suggests that members of the host community selected for former AMCO residents thought of these working-class newcomers as un-hygienic potential criminals. Later reports deemed the resettlement successful. Families were supposedly happy with their new residences, but relocation came at a substantial cost, both to the project’s funders and to the already established social ties of the people who experienced resettlement.

Mining history can benefit from looking seriously at slow-moving phenomena such as subsidence. Subsidence is such a common and pernicious hazard that it deserves a place in discussions of mining’s global impact, especially as the industry itself becomes more conscientious of what we now call its Corporate Social Responsibility (CSR).


Golder Associates Africa (Pty) Ltd. to ZCCM-Investment Holdings, Zambia – Copperbelt Environment Project: Resettlement Framework (Vol. 2): Resettlement Plan for the Amco Community—Kitwe Copperbelt Province. (Golder Associates Africa (Pty) Ltd.: Kitwe, Zambia, 2004).

Bob J. McCarthy, “Re-Claiming Butte: The Doctrine of Subjacent Support,” Montana Law Review 49, no. 2 (Summer 1988): 267-283.

Manuscript Collection 388, Dave Piper Collection, Butte-Silver Bow Public Archives.

Rob Nixon, Slow Violence and the Environmentalism of the Poor (Cambridge, MA: Harvard University Press, 2011), 2.

A.C. Waltham, Ground Subsidence (New York: Chapman and Hall, 1989), 1.

World Bank, Zambia – Copperbelt Environment Project (Washington, DC: World Bank Group, 2012), 2-4, 11-14.