Canada-based Dominion Diamond is planning to expand the Ekati diamond mine near Lac de Gras by developing the Jay and Cardinal kimberlite pipes.
The company has filed an application with the Wek'éezhii Land and Water Board (WLWB) requesting a new land use permit and a class A water licence.
The application represents the first stage in the regulatory approval process for which the detailed study work started after acquiring the mine from BHP Billiton in April 2013.
Dominion claims that the Jay-Cardinal project covers the largest diamondiferous resource in North America.
Drilling at the Jay pipe has established 78 million carats of indicated resource and 13 million carats of inferred resource.
The company said additional work at Jay during winter 2014 is designed to allow consideration of an open pit reserve to support development of the project.
The project has the potential to extend the operating life of the mine in the order of 10-20 years beyond 2019, when current reserves will be exhausted.
Dominion Diamond chairman and chief executive officer Robert Gannicott said, "The scale and robust nature of the Jay-Cardinal project has the potential to secure the future not just of the Ekati Diamond Mine but of the Northwest Territories diamond industry."
Follow-up delineation drilling programmes are planned at both Jay and Cardinal kimberlite pipes for late 2014.
Dominion has already started the initial work on a pre-feasibility report for the development, which it intends to complete in 2014.
Environmental assessment approval is expected to be secured before the end of 2015, after which construction would begin, leading to the planned release of diamond-bearing kimberlite to the process plant by 2019.
Ekati diamond mine was discovered in 1991, with diamond production formally starting in October 1998.
The first million tonnes of production was achieved by 1999 and in late 2010, a 78-carat diamond was discovered in the mine's output
Image: Aerial shot of the Ekati diamond mine. Photo: Courtesy of BHP Billiton.