Situated at 2,000 m in the Andes, 60 km to the east of Rancagua, in an environment marked by extremes of climate, Sewell Mining Town was built by the Braden Copper company in 1905 to house workers at what was to become the world’s largest underground copper mine, El Teniente. It is an outstanding example of the company towns that were born in many remote parts of the world from the fusion of local labour and resources from an industrialized nation, to mine and process high-value natural resources. The town was built on a terrain too steep for wheeled vehicles around a large central staircase rising from the railway station. Along its route formal squares of irregular shape with ornamental trees and plants constituted the main public spaces or squares of the town. The buildings lining the streets are timber, often painted in vivid green, yellow, red and blue. At its peak Sewell numbered 15,000 inhabitants, but was largely abandoned in the 1970s.
The existence of the el Teniente copper deposits seems to have been known and mined in pre-Hispanic times. During the 15th - 17th centuries, raw materials were exported by the Spanish and then for two hundred years there was little activity. In 1897 the then owner of the mining rights initiated a survey of the copper seams in the area. On discovering the huge potential of the site, and the fact that extracting the copper would require great investment, an approach was made in 1903 to the North American mining engineer William Braden who had taken part in the Great Exhibition in Santiago in 1894.
Braden arrived in Chile the following year, 1904, and begun acquiring the property. Almost immediately a road was constructed to the nearest railway line at Rancagua. Braden joined forces with E W Nash, President of the American Smelting and Refining Company and with Barton Sewell, the founder and Vice-President, they created the Braden Copper Company.
Over the next two years the infrastructure was developed, customs exemption agreed by the government of Chile for the large amounts of machinery to be imported from the US, and the mine equipped. By 1906, the first mill and concentrator had been erected, a lift established and an electricity generator installed. All these works involved what was then cutting edge technology, but in an extremely remote and hostile environment which initially led to set-backs. However, mining was officially authorised and begun in 1905.
In 1909 the recession in the US led to financial difficulties and fresh funds were injected by a company belonging to the Guggenheim brothers who took overall control in 1915 and the Braden Copper Company became a subsidiary of Kennecott Copper Corporation.
The operation base for the company was located at Rancagua which developed rapidly as a town. In 1917, the old foundry at Sewell was replaced by a more modern one in Caletones, where a new town also developed.
Although the company was prosperous, conditions for the mine workers in terms of industrial safety was not good. In 1945 a major, tragic, disaster occurred which spotlighted the problems: a fire in the entrance to the mine sent smoke to the galleries below choking 355 workers to death. The ‘Smoke Tragedy' led to a government investigation and a widespread national debate on the inadequacy of safety legislation and the power wielded by foreign companies. The company responded by developing a large department of industrial safety.
By the 1950s Chile had become the second largest copper producer in the world. As a result of ‘Chilenization' in 1967, the Government of Chile gained a 51% share of the mine and in 1971 the industry was nationalised and the company became a division of the Copper Corporation of Chile. This brought changes such as the El Teniente Club becoming the miners' cafeteria and the class A housing and other buildings being demolished.
At this time a decision was taken to move the population of Sewell further down the valley, in order to provide better facilities.
The town was abandoned as a mining settlement in 1980, remaining in partial use as a dormitory for contractors' personnel, and this led to the modification of some of the buildings and further demolition of others.
Demolition was finally halted at the end of the 1980s and in 1998 the town was declared a national monument.
Source: Advisory Body Evaluation
The mine however still functions and el Teniente division of the Copper Corporation now produces 3% of the worlds' copper.