Oyu Tolgoi and Redpath Mongolia creating one of the world’s biggest block cave mines

Achieving 10km milestone represents progress in the timeline of Oyu Tolgoi project

Ulaanbaatar, Mongolia ( – Oyu Tolgoi LLC and site contractor Redpath Mongolia LLC have completed 10km of lateral advance at a level 1300m below the surface. Together, they are achieving drift development, underground construction and surface support activities at the Oyu Tolgoi mine site.

Major development work started in 2008 to further explore the Hugo North ore body and now the operators are 10km closer to establishing one of the world’s biggest block cave mines.

This achievement is attributed to a skilled underground mining Mongolian workforce who continues to learn skills from several expatriate underground miners. This group of Mongolian workers is now achieving world-class results in safety, quality and advance rates.

Excavation work is taking place at the 1300m depth level of Shaft 1. A typical mining heading is 5.0m wide x 5.5m high and is excavated with a 2.5 metre radius profile. After using sprayed concrete and ensuring that the ground is supported, it is advanced by drilling with an Atlas Copco M2C computerised drill to a blast pattern of approximately 50 blast holes that are 45mm in diameter.

A bulk emulsion product is then pumped into the blast holes, with a lower density product used in perimeter holes to minimise over break and improve ground control. Non-electric detonators are enacted via a remote system which ensures that all personnel are in a safe location at the time of blasting.

After blasting, the heading is checked for gases by an authorised and competent professional, before other personnel are allowed to re-enter the work area. The walls, roof and blasted rock are washed down to minimise dust. Then, an underground loader is used to move the blasted material to an underground haul truck which travels to Shaft 1.  At this point, the material is then hoisted to surface.

This process has been repeated underground over 2500 times at Oyu Tolgoi, where they have now achieved 10km of lateral advance at 1300 metres below the surface.

Given the current mine design planned for the block cave, this is one milestone among many to come as the team works to complete over 150km of underground development.

About Oyu Tolgoi LLC (

Oyu Tolgoi LLC is Mongolia's largest copper and gold mining company and is a strategic partnership between the Government of Mongolia (34 per cent stake), Ivanhoe Mines (66 per cent) and Rio Tinto. Rio Tinto is the major shareholder in Ivanhoe Mines and the manager of Oyu Tolgoi. In addition to dividends from its 34 per cent stake in Oyu Tolgoi, the Government of Mongolia will receive taxes and royalties.

Oyu Tolgoi, located in the Gobi desert in southern Mongolia, will be one of the largest and highest-grade copper and gold mines in the world. It is the largest project ever developed in Mongolia, requiring a capital investment for Phase one of more than US$6 billion.

Oyu Tolgoi is committed to contributing to a sustainable future for Mongolia. At least 9 out of 10 employees will be Mongolian once the mine is in production and Oyu Tolgoi is investing US$58 million dollars (78 billion MNT) in training and education and an additional US$27 million dollars (36 billion MNT) in the Workforce Employment Project designed to help address the general skills shortage in Mongolia.

Oyu Tolgoi's key priorities are the health and safety of employees, best-practice environmental management, contributing to sustainable communities and always doing business with integrity, for the benefit of all the project's shareholders and the people of Mongolia.

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About Oyu Tolgoi LLC (

Oyu Tolgoi LLC, Mongolia's largest copper and gold mining company, is a strategic partnership between the Government of Mongolia, Turquoise Hill Resources and Rio Tinto. Located in the South Gobi, Oyu Tolgoi commenced shipment of product to customers in July 2013. Oyu Tolgoi is managed by Rio Tinto, which is investing global expertise and cutting-edge technology to help develop Mongolia’s mining industry and ensure Oyu Tolgoi is one of the world’s most advanced mines. For Oyu Tolgoi, nothing matters more than safety. The business operates under the principle that if a job cannot be done safely, it will not be done at all.

For more information, connect with us on Facebook and Twitter.