The Beginning of Potrerillos
(Information primarily derived from the Doctoral Thesis of Angela Vergara)
Potrerillos was known as a mining area from early in the 1800's. The area began to change when the railroad arrived at Pueblo Hundido in 1897, bringing new people and investment. In 1906 Manuel Zamorano & Vicente Echevarría founded the "Compania Minera de Potrerillos". They faced major challenges with lack of transportation and poor technology.
1913 - William Braden, already a famous miner in Chile, arrived in the area and purchased the company from Zamorano and Echevarría, along with other mining claims in the area. All together Braden purchased approximately 3,532 acres. Around the same time, The Anaconda Company contacted Braden and asked him to find them some good mining properties in Chile. The Andes Exploration Company of Maine was formed as a subsidiary of Anaconda to finance the exploration of the Potrerillos mining claims. At this time approximately 500 people worked on the exploration effort in the area that later became known as "La Mina."
1916 - In January, Braden sold his mining rights to the recently formed ANDES COPPER MINING COMPANY, a wholly owned subsidiary of The Anaconda Company. Potrerillos was Anaconda's first investment in Chile.
1916 to 1927 - Andes Copper Mining Company completed a massive effort to get the mine and smelter up and running. The first challenges involved building the necessary infrastructure, including transportation systems, water systems, housing, roads, etc.
One of the first tasks was to build a transportation system to connect the mine to the national railway at Pueblo Hundido and to the international markets. Three rail lines were built and completed by 1919. One from the Potrerillos smelter to Pueblo Hundido (56 miles), another from the smelter to the mine (5.5 miles) and finally from the port of Barquito to the state railway at Chañaral (2.85 miles). In charge of the railway construction were two Chilean engineers, Hermógenes Pizzaro and George Edgar Montandon, who died in an accident in 1918. All three of these rail lines were owned by the Anaconda subsidiary Potrerillos Railway Company which was incorporated in 1916. The cost of construction was approximately $3.5 Million. With the completion of the railway it was possible to bring the people and materiel to move ahead with construction. The mine and transportation systems were designed by William Wraith and the smelter was designed by Wilbur Jurden. Frederick Laist, Chief Metallurgist of Anaconda also played a critical role. Louis R. Wallace was the first General Manager who, along with a team of engineers, arrived in 1916 to begin the construction.
Besides solving the transportation problem ACMC was faced with the challenge of securing sources of energy and water. A steam Power plant was built in Barquito, with a capacity of 30,000 kilowatts. The only reasonable source of water was the La Ola River, 25 miles east of Potrerillos. The river flowed about 9 miles along the surface and then disappeared. W.B Saunders led a team that designed a diversion dam, a 28 mile line pipeline and 7 tunnels. The long, challenging and expensive construction project started in 1925. The most expensive part of the construction was transporting the pipe material from the assembly plant to the intake at the La Ola Dam. Mule carts had to follow a 45 kilometer zigzag trail through rugged terrain in all kinds of difficult weather.
1920 to 1925 – In 1920 Anaconda briefly shut down the construction project due to a lack of fuel. For other reasons, the company reduced construction efforts between 1921 and 1923 and completely suspended them in 1924. This was likely due to a depressed international copper market. The crisis lasted two years and in 1925 work was resumed under the supervision of Oscar M. Kuchs, the new General Manager, who had worked in Potrerillos in the early 1920’s. A new group of engineers arrived in the first quarter of 1925, Norbert F. Koepel, Superintendent of Crushing & Concentrating Plants, Albert A. Tabor, in charge of the Brick Plant, Thomas F. Humphrey, Smelter Superintendent.
Finally, in 1926, after 9 years of work, the mine began delivering ore to the primary crushing plant and in January 1927 the first bar of blister copper was produced. “This was an exciting event, as William Humphrey, son of Thomas Humphrey remembered: “The day I was born, which was January 12, 1927, was the day they poured the first copper at the smelter. So it was an exciting day for my dad. The problem was, he didn’t make it to the hospital; he was too busy watching the casting machine on the smelter dock. So I heard about that most of my live from my mother.”
In 1927, the company was finally ready to start copper production, after an investment of about $45 Million on the Potrerillos property.
All together, the Andes Copper Mining Company built an interconnected systems of 5 camps, distributed from the coast to the mine, the camps were:
Barquito – Port Facilities and Power Plant
Llanta – Machine Shops and Railway Maintenance
Potrerillos – Main Camp, Management Office and Plants
Las Vegas – Repair Shops and Sawmill
La Mina – The Underground Mine